gianfar: Fix kfree(skb)
[safe/jmp/linux-2.6] / drivers / ide / ide-tape.c
index 2a4a652..4e6181c 100644 (file)
@@ -15,7 +15,9 @@
  * Documentation/ide/ChangeLog.ide-tape.1995-2002
  */
 
-#define IDETAPE_VERSION "1.19"
+#define DRV_NAME "ide-tape"
+
+#define IDETAPE_VERSION "1.20"
 
 #include <linux/module.h>
 #include <linux/types.h>
 #include <linux/completion.h>
 #include <linux/bitops.h>
 #include <linux/mutex.h>
+#include <scsi/scsi.h>
 
 #include <asm/byteorder.h>
-#include <asm/irq.h>
-#include <asm/uaccess.h>
-#include <asm/io.h>
+#include <linux/irq.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
 #include <asm/unaligned.h>
-
-/*
- * partition
- */
-typedef struct os_partition_s {
-       __u8    partition_num;
-       __u8    par_desc_ver;
-       __u16   wrt_pass_cntr;
-       __u32   first_frame_addr;
-       __u32   last_frame_addr;
-       __u32   eod_frame_addr;
-} os_partition_t;
-
-/*
- * DAT entry
- */
-typedef struct os_dat_entry_s {
-       __u32   blk_sz;
-       __u16   blk_cnt;
-       __u8    flags;
-       __u8    reserved;
-} os_dat_entry_t;
-
-/*
- * DAT
- */
-#define OS_DAT_FLAGS_DATA      (0xc)
-#define OS_DAT_FLAGS_MARK      (0x1)
-
-typedef struct os_dat_s {
-       __u8            dat_sz;
-       __u8            reserved1;
-       __u8            entry_cnt;
-       __u8            reserved3;
-       os_dat_entry_t  dat_list[16];
-} os_dat_t;
-
 #include <linux/mtio.h>
 
-/**************************** Tunable parameters *****************************/
-
-
-/*
- *     Pipelined mode parameters.
- *
- *     We try to use the minimum number of stages which is enough to
- *     keep the tape constantly streaming. To accomplish that, we implement
- *     a feedback loop around the maximum number of stages:
- *
- *     We start from MIN maximum stages (we will not even use MIN stages
- *      if we don't need them), increment it by RATE*(MAX-MIN)
- *     whenever we sense that the pipeline is empty, until we reach
- *     the optimum value or until we reach MAX.
- *
- *     Setting the following parameter to 0 is illegal: the pipelined mode
- *     cannot be disabled (calculate_speeds() divides by tape->max_stages.)
- */
-#define IDETAPE_MIN_PIPELINE_STAGES      1
-#define IDETAPE_MAX_PIPELINE_STAGES    400
-#define IDETAPE_INCREASE_STAGES_RATE    20
+enum {
+       /* output errors only */
+       DBG_ERR =               (1 << 0),
+       /* output all sense key/asc */
+       DBG_SENSE =             (1 << 1),
+       /* info regarding all chrdev-related procedures */
+       DBG_CHRDEV =            (1 << 2),
+       /* all remaining procedures */
+       DBG_PROCS =             (1 << 3),
+};
 
-/*
- *     The following are used to debug the driver:
- *
- *     Setting IDETAPE_DEBUG_LOG to 1 will log driver flow control.
- *
- *     Setting them to 0 will restore normal operation mode:
- *
- *             1.      Disable logging normal successful operations.
- *             2.      Disable self-sanity checks.
- *             3.      Errors will still be logged, of course.
- *
- *     All the #if DEBUG code will be removed some day, when the driver
- *     is verified to be stable enough. This will make it much more
- *     esthetic.
- */
+/* define to see debug info */
 #define IDETAPE_DEBUG_LOG              0
 
+#if IDETAPE_DEBUG_LOG
+#define debug_log(lvl, fmt, args...)                   \
+{                                                      \
+       if (tape->debug_mask & lvl)                     \
+       printk(KERN_INFO "ide-tape: " fmt, ## args);    \
+}
+#else
+#define debug_log(lvl, fmt, args...) do {} while (0)
+#endif
+
+/**************************** Tunable parameters *****************************/
 /*
- *     After each failed packet command we issue a request sense command
- *     and retry the packet command IDETAPE_MAX_PC_RETRIES times.
+ * After each failed packet command we issue a request sense command and retry
+ * the packet command IDETAPE_MAX_PC_RETRIES times.
  *
- *     Setting IDETAPE_MAX_PC_RETRIES to 0 will disable retries.
+ * Setting IDETAPE_MAX_PC_RETRIES to 0 will disable retries.
  */
 #define IDETAPE_MAX_PC_RETRIES         3
 
 /*
- *     With each packet command, we allocate a buffer of
- *     IDETAPE_PC_BUFFER_SIZE bytes. This is used for several packet
- *     commands (Not for READ/WRITE commands).
+ * The following parameter is used to select the point in the internal tape fifo
+ * in which we will start to refill the buffer. Decreasing the following
+ * parameter will improve the system's latency and interactive response, while
+ * using a high value might improve system throughput.
  */
-#define IDETAPE_PC_BUFFER_SIZE         256
+#define IDETAPE_FIFO_THRESHOLD         2
 
 /*
- *     In various places in the driver, we need to allocate storage
- *     for packet commands and requests, which will remain valid while
- *     we leave the driver to wait for an interrupt or a timeout event.
- */
-#define IDETAPE_PC_STACK               (10 + IDETAPE_MAX_PC_RETRIES)
-
-/*
- * Some drives (for example, Seagate STT3401A Travan) require a very long
- * timeout, because they don't return an interrupt or clear their busy bit
- * until after the command completes (even retension commands).
- */
-#define IDETAPE_WAIT_CMD               (900*HZ)
-
-/*
- *     The following parameter is used to select the point in the internal
- *     tape fifo in which we will start to refill the buffer. Decreasing
- *     the following parameter will improve the system's latency and
- *     interactive response, while using a high value might improve system
- *     throughput.
- */
-#define IDETAPE_FIFO_THRESHOLD                 2
-
-/*
- *     DSC polling parameters.
+ * DSC polling parameters.
  *
- *     Polling for DSC (a single bit in the status register) is a very
- *     important function in ide-tape. There are two cases in which we
- *     poll for DSC:
+ * Polling for DSC (a single bit in the status register) is a very important
+ * function in ide-tape. There are two cases in which we poll for DSC:
  *
- *     1.      Before a read/write packet command, to ensure that we
- *             can transfer data from/to the tape's data buffers, without
- *             causing an actual media access. In case the tape is not
- *             ready yet, we take out our request from the device
- *             request queue, so that ide.c will service requests from
- *             the other device on the same interface meanwhile.
+ * 1. Before a read/write packet command, to ensure that we can transfer data
+ * from/to the tape's data buffers, without causing an actual media access.
+ * In case the tape is not ready yet, we take out our request from the device
+ * request queue, so that ide.c could service requests from the other device
+ * on the same interface in the meantime.
  *
- *     2.      After the successful initialization of a "media access
- *             packet command", which is a command which can take a long
- *             time to complete (it can be several seconds or even an hour).
+ * 2. After the successful initialization of a "media access packet command",
+ * which is a command that can take a long time to complete (the interval can
+ * range from several seconds to even an hour). Again, we postpone our request
+ * in the middle to free the bus for the other device. The polling frequency
+ * here should be lower than the read/write frequency since those media access
+ * commands are slow. We start from a "fast" frequency - IDETAPE_DSC_MA_FAST
+ * (1 second), and if we don't receive DSC after IDETAPE_DSC_MA_THRESHOLD
+ * (5 min), we switch it to a lower frequency - IDETAPE_DSC_MA_SLOW (1 min).
  *
- *             Again, we postpone our request in the middle to free the bus
- *             for the other device. The polling frequency here should be
- *             lower than the read/write frequency since those media access
- *             commands are slow. We start from a "fast" frequency -
- *             IDETAPE_DSC_MA_FAST (one second), and if we don't receive DSC
- *             after IDETAPE_DSC_MA_THRESHOLD (5 minutes), we switch it to a
- *             lower frequency - IDETAPE_DSC_MA_SLOW (1 minute).
- *
- *     We also set a timeout for the timer, in case something goes wrong.
- *     The timeout should be longer then the maximum execution time of a
- *     tape operation.
- */
-/*
- *     DSC timings.
+ * We also set a timeout for the timer, in case something goes wrong. The
+ * timeout should be longer then the maximum execution time of a tape operation.
  */
+
+/* DSC timings. */
 #define IDETAPE_DSC_RW_MIN             5*HZ/100        /* 50 msec */
 #define IDETAPE_DSC_RW_MAX             40*HZ/100       /* 400 msec */
 #define IDETAPE_DSC_RW_TIMEOUT         2*60*HZ         /* 2 minutes */
@@ -202,19 +124,12 @@ typedef struct os_dat_s {
 
 /*************************** End of tunable parameters ***********************/
 
-/*
- *     Read/Write error simulation
- */
-#define SIMULATE_ERRORS                        0
-
-/*
- *     For general magnetic tape device compatibility.
- */
-typedef enum {
-       idetape_direction_none,
-       idetape_direction_read,
-       idetape_direction_write
-} idetape_chrdev_direction_t;
+/* tape directions */
+enum {
+       IDETAPE_DIR_NONE  = (1 << 0),
+       IDETAPE_DIR_READ  = (1 << 1),
+       IDETAPE_DIR_WRITE = (1 << 2),
+};
 
 struct idetape_bh {
        u32 b_size;
@@ -223,117 +138,57 @@ struct idetape_bh {
        char *b_data;
 };
 
-/*
- *     Our view of a packet command.
- */
-typedef struct idetape_packet_command_s {
-       u8 c[12];                               /* Actual packet bytes */
-       int retries;                            /* On each retry, we increment retries */
-       int error;                              /* Error code */
-       int request_transfer;                   /* Bytes to transfer */
-       int actually_transferred;               /* Bytes actually transferred */
-       int buffer_size;                        /* Size of our data buffer */
-       struct idetape_bh *bh;
-       char *b_data;
-       int b_count;
-       u8 *buffer;                             /* Data buffer */
-       u8 *current_position;                   /* Pointer into the above buffer */
-       ide_startstop_t (*callback) (ide_drive_t *);    /* Called when this packet command is completed */
-       u8 pc_buffer[IDETAPE_PC_BUFFER_SIZE];   /* Temporary buffer */
-       unsigned long flags;                    /* Status/Action bit flags: long for set_bit */
-} idetape_pc_t;
+/* Tape door status */
+#define DOOR_UNLOCKED                  0
+#define DOOR_LOCKED                    1
+#define DOOR_EXPLICITLY_LOCKED         2
 
-/*
- *     Packet command flag bits.
- */
-/* Set when an error is considered normal - We won't retry */
-#define        PC_ABORT                        0
-/* 1 When polling for DSC on a media access command */
-#define PC_WAIT_FOR_DSC                        1
-/* 1 when we prefer to use DMA if possible */
-#define PC_DMA_RECOMMENDED             2
-/* 1 while DMA in progress */
-#define        PC_DMA_IN_PROGRESS              3
-/* 1 when encountered problem during DMA */
-#define        PC_DMA_ERROR                    4
-/* Data direction */
-#define        PC_WRITING                      5
+/* Some defines for the SPACE command */
+#define IDETAPE_SPACE_OVER_FILEMARK    1
+#define IDETAPE_SPACE_TO_EOD           3
 
-/*
- *     Block Size Page
- */
-typedef struct {
-       unsigned        page_code       :6;     /* Page code - Should be 0x30 */
-       unsigned        reserved1_6     :1;
-       unsigned        ps              :1;
-       __u8            page_length;            /* Page Length - Should be 2 */
-       __u8            reserved2;
-       unsigned        play32          :1;
-       unsigned        play32_5        :1;
-       unsigned        reserved2_23    :2;
-       unsigned        record32        :1;
-       unsigned        record32_5      :1;
-       unsigned        reserved2_6     :1;
-       unsigned        one             :1;
-} idetape_block_size_page_t;
+/* Some defines for the LOAD UNLOAD command */
+#define IDETAPE_LU_LOAD_MASK           1
+#define IDETAPE_LU_RETENSION_MASK      2
+#define IDETAPE_LU_EOT_MASK            4
 
-/*
- *     A pipeline stage.
- */
-typedef struct idetape_stage_s {
-       struct request rq;                      /* The corresponding request */
-       struct idetape_bh *bh;                  /* The data buffers */
-       struct idetape_stage_s *next;           /* Pointer to the next stage */
-} idetape_stage_t;
+/* Error codes returned in rq->errors to the higher part of the driver. */
+#define IDETAPE_ERROR_GENERAL          101
+#define IDETAPE_ERROR_FILEMARK         102
+#define IDETAPE_ERROR_EOD              103
+
+/* Structures related to the SELECT SENSE / MODE SENSE packet commands. */
+#define IDETAPE_BLOCK_DESCRIPTOR       0
+#define IDETAPE_CAPABILITIES_PAGE      0x2a
 
 /*
- *     Most of our global data which we need to save even as we leave the
- *     driver due to an interrupt or a timer event is stored in a variable
- *     of type idetape_tape_t, defined below.
+ * Most of our global data which we need to save even as we leave the driver due
+ * to an interrupt or a timer event is stored in the struct defined below.
  */
 typedef struct ide_tape_obj {
-       ide_drive_t     *drive;
-       ide_driver_t    *driver;
-       struct gendisk  *disk;
-       struct kref     kref;
+       ide_drive_t             *drive;
+       struct ide_driver       *driver;
+       struct gendisk          *disk;
+       struct device           dev;
 
        /*
-        *      Since a typical character device operation requires more
-        *      than one packet command, we provide here enough memory
-        *      for the maximum of interconnected packet commands.
-        *      The packet commands are stored in the circular array pc_stack.
-        *      pc_stack_index points to the last used entry, and warps around
-        *      to the start when we get to the last array entry.
-        *
-        *      pc points to the current processed packet command.
-        *
         *      failed_pc points to the last failed packet command, or contains
         *      NULL if we do not need to retry any packet command. This is
         *      required since an additional packet command is needed before the
         *      retry, to get detailed information on what went wrong.
         */
-       /* Current packet command */
-       idetape_pc_t *pc;
        /* Last failed packet command */
-       idetape_pc_t *failed_pc;
-       /* Packet command stack */
-       idetape_pc_t pc_stack[IDETAPE_PC_STACK];
-       /* Next free packet command storage space */
-       int pc_stack_index;
-       struct request rq_stack[IDETAPE_PC_STACK];
-       /* We implement a circular array */
-       int rq_stack_index;
+       struct ide_atapi_pc *failed_pc;
+       /* used by REQ_IDETAPE_{READ,WRITE} requests */
+       struct ide_atapi_pc queued_pc;
 
        /*
-        *      DSC polling variables.
+        * DSC polling variables.
         *
-        *      While polling for DSC we use postponed_rq to postpone the
-        *      current request so that ide.c will be able to service
-        *      pending requests on the other device. Note that at most
-        *      we will have only one DSC (usually data transfer) request
-        *      in the device request queue. Additional requests can be
-        *      queued in our internal pipeline, but they will be visible
-        *      to ide.c only one at a time.
+        * While polling for DSC we use postponed_rq to postpone the current
+        * request so that ide.c will be able to service pending requests on the
+        * other device. Note that at most we will have only one DSC (usually
+        * data transfer) request in the device request queue.
         */
        struct request *postponed_rq;
        /* The time in which we started polling for DSC */
@@ -341,111 +196,63 @@ typedef struct ide_tape_obj {
        /* Timer used to poll for dsc */
        struct timer_list dsc_timer;
        /* Read/Write dsc polling frequency */
-       unsigned long best_dsc_rw_frequency;
-       /* The current polling frequency */
-       unsigned long dsc_polling_frequency;
-       /* Maximum waiting time */
+       unsigned long best_dsc_rw_freq;
+       unsigned long dsc_poll_freq;
        unsigned long dsc_timeout;
 
-       /*
-        *      Read position information
-        */
+       /* Read position information */
        u8 partition;
        /* Current block */
-       unsigned int first_frame_position;
-       unsigned int last_frame_position;
-       unsigned int blocks_in_buffer;
+       unsigned int first_frame;
 
-       /*
-        *      Last error information
-        */
+       /* Last error information */
        u8 sense_key, asc, ascq;
 
-       /*
-        *      Character device operation
-        */
+       /* Character device operation */
        unsigned int minor;
        /* device name */
        char name[4];
        /* Current character device data transfer direction */
-       idetape_chrdev_direction_t chrdev_direction;
+       u8 chrdev_dir;
 
-       /*
-        *      Device information
-        */
-       /* Usually 512 or 1024 bytes */
-       unsigned short tape_block_size;
+       /* tape block size, usually 512 or 1024 bytes */
+       unsigned short blk_size;
        int user_bs_factor;
 
        /* Copy of the tape's Capabilities and Mechanical Page */
        u8 caps[20];
 
        /*
-        *      Active data transfer request parameters.
+        * Active data transfer request parameters.
         *
-        *      At most, there is only one ide-tape originated data transfer
-        *      request in the device request queue. This allows ide.c to
-        *      easily service requests from the other device when we
-        *      postpone our active request. In the pipelined operation
-        *      mode, we use our internal pipeline structure to hold
-        *      more data requests.
-        *
-        *      The data buffer size is chosen based on the tape's
-        *      recommendation.
+        * At most, there is only one ide-tape originated data transfer request
+        * in the device request queue. This allows ide.c to easily service
+        * requests from the other device when we postpone our active request.
         */
-       /* Pointer to the request which is waiting in the device request queue */
-       struct request *active_data_request;
-       /* Data buffer size (chosen based on the tape's recommendation */
-       int stage_size;
-       idetape_stage_t *merge_stage;
-       int merge_stage_size;
+
+       /* Data buffer size chosen based on the tape's recommendation */
+       int buffer_size;
+       /* merge buffer */
+       struct idetape_bh *merge_bh;
+       /* size of the merge buffer */
+       int merge_bh_size;
+       /* pointer to current buffer head within the merge buffer */
        struct idetape_bh *bh;
        char *b_data;
        int b_count;
-       
-       /*
-        *      Pipeline parameters.
-        *
-        *      To accomplish non-pipelined mode, we simply set the following
-        *      variables to zero (or NULL, where appropriate).
-        */
-       /* Number of currently used stages */
-       int nr_stages;
-       /* Number of pending stages */
-       int nr_pending_stages;
-       /* We will not allocate more than this number of stages */
-       int max_stages, min_pipeline, max_pipeline;
-       /* The first stage which will be removed from the pipeline */
-       idetape_stage_t *first_stage;
-       /* The currently active stage */
-       idetape_stage_t *active_stage;
-       /* Will be serviced after the currently active request */
-       idetape_stage_t *next_stage;
-       /* New requests will be added to the pipeline here */
-       idetape_stage_t *last_stage;
-       /* Optional free stage which we can use */
-       idetape_stage_t *cache_stage;
-       int pages_per_stage;
+
+       int pages_per_buffer;
        /* Wasted space in each stage */
        int excess_bh_size;
 
-       /* Status/Action flags: long for set_bit */
-       unsigned long flags;
        /* protects the ide-tape queue */
-       spinlock_t spinlock;
+       spinlock_t lock;
 
-       /*
-        * Measures average tape speed
-        */
+       /* Measures average tape speed */
        unsigned long avg_time;
        int avg_size;
        int avg_speed;
 
-       char vendor_id[10];
-       char product_id[18];
-       char firmware_revision[6];
-       int firmware_revision_num;
-
        /* the door is currently locked */
        int door_locked;
        /* the tape hardware is write protected */
@@ -453,246 +260,46 @@ typedef struct ide_tape_obj {
        /* the tape is write protected (hardware or opened as read-only) */
        char write_prot;
 
-       /*
-        * Limit the number of times a request can
-        * be postponed, to avoid an infinite postpone
-        * deadlock.
-        */
-       /* request postpone count limit */
-       int postpone_cnt;
-
-       /*
-        * Measures number of frames:
-        *
-        * 1. written/read to/from the driver pipeline (pipeline_head).
-        * 2. written/read to/from the tape buffers (idetape_bh).
-        * 3. written/read by the tape to/from the media (tape_head).
-        */
-       int pipeline_head;
-       int buffer_head;
-       int tape_head;
-       int last_tape_head;
-
-       /*
-        * Speed control at the tape buffers input/output
-        */
-       unsigned long insert_time;
-       int insert_size;
-       int insert_speed;
-       int max_insert_speed;
-       int measure_insert_time;
-
-       /*
-        * Measure tape still time, in milliseconds
-        */
-       unsigned long tape_still_time_begin;
-       int tape_still_time;
-
-       /*
-        * Speed regulation negative feedback loop
-        */
-       int speed_control;
-       int pipeline_head_speed;
-       int controlled_pipeline_head_speed;
-       int uncontrolled_pipeline_head_speed;
-       int controlled_last_pipeline_head;
-       int uncontrolled_last_pipeline_head;
-       unsigned long uncontrolled_pipeline_head_time;
-       unsigned long controlled_pipeline_head_time;
-       int controlled_previous_pipeline_head;
-       int uncontrolled_previous_pipeline_head;
-       unsigned long controlled_previous_head_time;
-       unsigned long uncontrolled_previous_head_time;
-       int restart_speed_control_req;
-
-        /*
-         * Debug_level determines amount of debugging output;
-         * can be changed using /proc/ide/hdx/settings
-         * 0 : almost no debugging output
-         * 1 : 0+output errors only
-         * 2 : 1+output all sensekey/asc
-         * 3 : 2+follow all chrdev related procedures
-         * 4 : 3+follow all procedures
-         * 5 : 4+include pc_stack rq_stack info
-         * 6 : 5+USE_COUNT updates
-         */
-         int debug_level; 
+       u32 debug_mask;
 } idetape_tape_t;
 
 static DEFINE_MUTEX(idetape_ref_mutex);
 
 static struct class *idetape_sysfs_class;
 
-#define to_ide_tape(obj) container_of(obj, struct ide_tape_obj, kref)
-
-#define ide_tape_g(disk) \
-       container_of((disk)->private_data, struct ide_tape_obj, driver)
+static void ide_tape_release(struct device *);
 
 static struct ide_tape_obj *ide_tape_get(struct gendisk *disk)
 {
        struct ide_tape_obj *tape = NULL;
 
        mutex_lock(&idetape_ref_mutex);
-       tape = ide_tape_g(disk);
-       if (tape)
-               kref_get(&tape->kref);
+       tape = ide_drv_g(disk, ide_tape_obj);
+       if (tape) {
+               if (ide_device_get(tape->drive))
+                       tape = NULL;
+               else
+                       get_device(&tape->dev);
+       }
        mutex_unlock(&idetape_ref_mutex);
        return tape;
 }
 
-static void ide_tape_release(struct kref *);
-
 static void ide_tape_put(struct ide_tape_obj *tape)
 {
+       ide_drive_t *drive = tape->drive;
+
        mutex_lock(&idetape_ref_mutex);
-       kref_put(&tape->kref, ide_tape_release);
+       put_device(&tape->dev);
+       ide_device_put(drive);
        mutex_unlock(&idetape_ref_mutex);
 }
 
 /*
- *     Tape door status
+ * The variables below are used for the character device interface. Additional
+ * state variables are defined in our ide_drive_t structure.
  */
-#define DOOR_UNLOCKED                  0
-#define DOOR_LOCKED                    1
-#define DOOR_EXPLICITLY_LOCKED         2
-
-/*
- *     Tape flag bits values.
- */
-#define IDETAPE_IGNORE_DSC             0
-#define IDETAPE_ADDRESS_VALID          1       /* 0 When the tape position is unknown */
-#define IDETAPE_BUSY                   2       /* Device already opened */
-#define IDETAPE_PIPELINE_ERROR         3       /* Error detected in a pipeline stage */
-#define IDETAPE_DETECT_BS              4       /* Attempt to auto-detect the current user block size */
-#define IDETAPE_FILEMARK               5       /* Currently on a filemark */
-#define IDETAPE_DRQ_INTERRUPT          6       /* DRQ interrupt device */
-#define IDETAPE_READ_ERROR             7
-#define IDETAPE_PIPELINE_ACTIVE                8       /* pipeline active */
-/* 0 = no tape is loaded, so we don't rewind after ejecting */
-#define IDETAPE_MEDIUM_PRESENT         9
-
-/*
- *     Supported ATAPI tape drives packet commands
- */
-#define IDETAPE_TEST_UNIT_READY_CMD    0x00
-#define IDETAPE_REWIND_CMD             0x01
-#define IDETAPE_REQUEST_SENSE_CMD      0x03
-#define IDETAPE_READ_CMD               0x08
-#define IDETAPE_WRITE_CMD              0x0a
-#define IDETAPE_WRITE_FILEMARK_CMD     0x10
-#define IDETAPE_SPACE_CMD              0x11
-#define IDETAPE_INQUIRY_CMD            0x12
-#define IDETAPE_ERASE_CMD              0x19
-#define IDETAPE_MODE_SENSE_CMD         0x1a
-#define IDETAPE_MODE_SELECT_CMD                0x15
-#define IDETAPE_LOAD_UNLOAD_CMD                0x1b
-#define IDETAPE_PREVENT_CMD            0x1e
-#define IDETAPE_LOCATE_CMD             0x2b
-#define IDETAPE_READ_POSITION_CMD      0x34
-#define IDETAPE_READ_BUFFER_CMD                0x3c
-#define IDETAPE_SET_SPEED_CMD          0xbb
-
-/*
- *     Some defines for the READ BUFFER command
- */
-#define IDETAPE_RETRIEVE_FAULTY_BLOCK  6
-
-/*
- *     Some defines for the SPACE command
- */
-#define IDETAPE_SPACE_OVER_FILEMARK    1
-#define IDETAPE_SPACE_TO_EOD           3
-
-/*
- *     Some defines for the LOAD UNLOAD command
- */
-#define IDETAPE_LU_LOAD_MASK           1
-#define IDETAPE_LU_RETENSION_MASK      2
-#define IDETAPE_LU_EOT_MASK            4
-
-/*
- *     Special requests for our block device strategy routine.
- *
- *     In order to service a character device command, we add special
- *     requests to the tail of our block device request queue and wait
- *     for their completion.
- */
-
-enum {
-       REQ_IDETAPE_PC1         = (1 << 0), /* packet command (first stage) */
-       REQ_IDETAPE_PC2         = (1 << 1), /* packet command (second stage) */
-       REQ_IDETAPE_READ        = (1 << 2),
-       REQ_IDETAPE_WRITE       = (1 << 3),
-       REQ_IDETAPE_READ_BUFFER = (1 << 4),
-};
-
-/*
- *     Error codes which are returned in rq->errors to the higher part
- *     of the driver.
- */
-#define        IDETAPE_ERROR_GENERAL           101
-#define        IDETAPE_ERROR_FILEMARK          102
-#define        IDETAPE_ERROR_EOD               103
-
-/*
- *     The following is used to format the general configuration word of
- *     the ATAPI IDENTIFY DEVICE command.
- */
-struct idetape_id_gcw {        
-       unsigned packet_size            :2;     /* Packet Size */
-       unsigned reserved234            :3;     /* Reserved */
-       unsigned drq_type               :2;     /* Command packet DRQ type */
-       unsigned removable              :1;     /* Removable media */
-       unsigned device_type            :5;     /* Device type */
-       unsigned reserved13             :1;     /* Reserved */
-       unsigned protocol               :2;     /* Protocol type */
-};
-
-/*
- *     READ POSITION packet command - Data Format (From Table 6-57)
- */
-typedef struct {
-       unsigned        reserved0_10    :2;     /* Reserved */
-       unsigned        bpu             :1;     /* Block Position Unknown */    
-       unsigned        reserved0_543   :3;     /* Reserved */
-       unsigned        eop             :1;     /* End Of Partition */
-       unsigned        bop             :1;     /* Beginning Of Partition */
-       u8              partition;              /* Partition Number */
-       u8              reserved2, reserved3;   /* Reserved */
-       u32             first_block;            /* First Block Location */
-       u32             last_block;             /* Last Block Location (Optional) */
-       u8              reserved12;             /* Reserved */
-       u8              blocks_in_buffer[3];    /* Blocks In Buffer - (Optional) */
-       u32             bytes_in_buffer;        /* Bytes In Buffer (Optional) */
-} idetape_read_position_result_t;
-
-/*
- *     Follows structures which are related to the SELECT SENSE / MODE SENSE
- *     packet commands. Those packet commands are still not supported
- *     by ide-tape.
- */
-#define IDETAPE_BLOCK_DESCRIPTOR       0
-#define        IDETAPE_CAPABILITIES_PAGE       0x2a
-#define IDETAPE_PARAMTR_PAGE           0x2b   /* Onstream DI-x0 only */
-#define IDETAPE_BLOCK_SIZE_PAGE                0x30
-#define IDETAPE_BUFFER_FILLING_PAGE    0x33
-
-/*
- *     Run time configurable parameters.
- */
-typedef struct {
-       int     dsc_rw_frequency;
-       int     dsc_media_access_frequency;
-       int     nr_stages;
-} idetape_config_t;
-
-/*
- *     The variables below are used for the character device interface.
- *     Additional state variables are defined in our ide_drive_t structure.
- */
-static struct ide_tape_obj * idetape_devs[MAX_HWIFS * MAX_DRIVES];
-
-#define ide_tape_f(file) ((file)->private_data)
+static struct ide_tape_obj *idetape_devs[MAX_HWIFS * MAX_DRIVES];
 
 static struct ide_tape_obj *ide_tape_chrdev_get(unsigned int i)
 {
@@ -701,29 +308,13 @@ static struct ide_tape_obj *ide_tape_chrdev_get(unsigned int i)
        mutex_lock(&idetape_ref_mutex);
        tape = idetape_devs[i];
        if (tape)
-               kref_get(&tape->kref);
+               get_device(&tape->dev);
        mutex_unlock(&idetape_ref_mutex);
        return tape;
 }
 
-/*
- *      Function declarations
- *
- */
-static int idetape_chrdev_release (struct inode *inode, struct file *filp);
-static void idetape_write_release (ide_drive_t *drive, unsigned int minor);
-
-/*
- * Too bad. The drive wants to send us data which we are not ready to accept.
- * Just throw it away.
- */
-static void idetape_discard_data (ide_drive_t *drive, unsigned int bcount)
-{
-       while (bcount--)
-               (void) HWIF(drive)->INB(IDE_DATA_REG);
-}
-
-static void idetape_input_buffers (ide_drive_t *drive, idetape_pc_t *pc, unsigned int bcount)
+static void idetape_input_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc,
+                                 unsigned int bcount)
 {
        struct idetape_bh *bh = pc->bh;
        int count;
@@ -732,11 +323,14 @@ static void idetape_input_buffers (ide_drive_t *drive, idetape_pc_t *pc, unsigne
                if (bh == NULL) {
                        printk(KERN_ERR "ide-tape: bh == NULL in "
                                "idetape_input_buffers\n");
-                       idetape_discard_data(drive, bcount);
+                       ide_pad_transfer(drive, 0, bcount);
                        return;
                }
-               count = min((unsigned int)(bh->b_size - atomic_read(&bh->b_count)), bcount);
-               HWIF(drive)->atapi_input_bytes(drive, bh->b_data + atomic_read(&bh->b_count), count);
+               count = min(
+                       (unsigned int)(bh->b_size - atomic_read(&bh->b_count)),
+                       bcount);
+               drive->hwif->tp_ops->input_data(drive, NULL, bh->b_data +
+                                       atomic_read(&bh->b_count), count);
                bcount -= count;
                atomic_add(count, &bh->b_count);
                if (atomic_read(&bh->b_count) == bh->b_size) {
@@ -748,24 +342,26 @@ static void idetape_input_buffers (ide_drive_t *drive, idetape_pc_t *pc, unsigne
        pc->bh = bh;
 }
 
-static void idetape_output_buffers (ide_drive_t *drive, idetape_pc_t *pc, unsigned int bcount)
+static void idetape_output_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc,
+                                  unsigned int bcount)
 {
        struct idetape_bh *bh = pc->bh;
        int count;
 
        while (bcount) {
                if (bh == NULL) {
-                       printk(KERN_ERR "ide-tape: bh == NULL in "
-                               "idetape_output_buffers\n");
+                       printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
+                                       __func__);
                        return;
                }
                count = min((unsigned int)pc->b_count, (unsigned int)bcount);
-               HWIF(drive)->atapi_output_bytes(drive, pc->b_data, count);
+               drive->hwif->tp_ops->output_data(drive, NULL, pc->b_data, count);
                bcount -= count;
                pc->b_data += count;
                pc->b_count -= count;
                if (!pc->b_count) {
-                       pc->bh = bh = bh->b_reqnext;
+                       bh = bh->b_reqnext;
+                       pc->bh = bh;
                        if (bh) {
                                pc->b_data = bh->b_data;
                                pc->b_count = atomic_read(&bh->b_count);
@@ -774,18 +370,18 @@ static void idetape_output_buffers (ide_drive_t *drive, idetape_pc_t *pc, unsign
        }
 }
 
-static void idetape_update_buffers (idetape_pc_t *pc)
+static void idetape_update_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc)
 {
        struct idetape_bh *bh = pc->bh;
        int count;
-       unsigned int bcount = pc->actually_transferred;
+       unsigned int bcount = pc->xferred;
 
-       if (test_bit(PC_WRITING, &pc->flags))
+       if (pc->flags & PC_FLAG_WRITING)
                return;
        while (bcount) {
                if (bh == NULL) {
-                       printk(KERN_ERR "ide-tape: bh == NULL in "
-                               "idetape_update_buffers\n");
+                       printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
+                                       __func__);
                        return;
                }
                count = min((unsigned int)bh->b_size, (unsigned int)bcount);
@@ -798,97 +394,27 @@ static void idetape_update_buffers (idetape_pc_t *pc)
 }
 
 /*
- *     idetape_next_pc_storage returns a pointer to a place in which we can
- *     safely store a packet command, even though we intend to leave the
- *     driver. A storage space for a maximum of IDETAPE_PC_STACK packet
- *     commands is allocated at initialization time.
- */
-static idetape_pc_t *idetape_next_pc_storage (ide_drive_t *drive)
-{
-       idetape_tape_t *tape = drive->driver_data;
-
-#if IDETAPE_DEBUG_LOG
-       if (tape->debug_level >= 5)
-               printk(KERN_INFO "ide-tape: pc_stack_index=%d\n",
-                       tape->pc_stack_index);
-#endif /* IDETAPE_DEBUG_LOG */
-       if (tape->pc_stack_index == IDETAPE_PC_STACK)
-               tape->pc_stack_index=0;
-       return (&tape->pc_stack[tape->pc_stack_index++]);
-}
-
-/*
- *     idetape_next_rq_storage is used along with idetape_next_pc_storage.
- *     Since we queue packet commands in the request queue, we need to
- *     allocate a request, along with the allocation of a packet command.
- */
-/**************************************************************
- *                                                            *
- *  This should get fixed to use kmalloc(.., GFP_ATOMIC)      *
- *  followed later on by kfree().   -ml                       *
- *                                                            *
- **************************************************************/
-static struct request *idetape_next_rq_storage (ide_drive_t *drive)
-{
-       idetape_tape_t *tape = drive->driver_data;
-
-#if IDETAPE_DEBUG_LOG
-       if (tape->debug_level >= 5)
-               printk(KERN_INFO "ide-tape: rq_stack_index=%d\n",
-                       tape->rq_stack_index);
-#endif /* IDETAPE_DEBUG_LOG */
-       if (tape->rq_stack_index == IDETAPE_PC_STACK)
-               tape->rq_stack_index=0;
-       return (&tape->rq_stack[tape->rq_stack_index++]);
-}
-
-/*
- *     idetape_init_pc initializes a packet command.
- */
-static void idetape_init_pc (idetape_pc_t *pc)
-{
-       memset(pc->c, 0, 12);
-       pc->retries = 0;
-       pc->flags = 0;
-       pc->request_transfer = 0;
-       pc->buffer = pc->pc_buffer;
-       pc->buffer_size = IDETAPE_PC_BUFFER_SIZE;
-       pc->bh = NULL;
-       pc->b_data = NULL;
-}
-
-/*
  * called on each failed packet command retry to analyze the request sense. We
  * currently do not utilize this information.
  */
 static void idetape_analyze_error(ide_drive_t *drive, u8 *sense)
 {
        idetape_tape_t *tape = drive->driver_data;
-       idetape_pc_t *pc = tape->failed_pc;
+       struct ide_atapi_pc *pc = tape->failed_pc;
 
        tape->sense_key = sense[2] & 0xF;
        tape->asc       = sense[12];
        tape->ascq      = sense[13];
-#if IDETAPE_DEBUG_LOG
-       /*
-        * Without debugging, we only log an error if we decided to give up
-        * retrying.
-        */
-       if (tape->debug_level >= 1)
-               printk(KERN_INFO "ide-tape: pc = %x, sense key = %x, "
-                       "asc = %x, ascq = %x\n",
-                       pc->c[0], tape->sense_key,
-                       tape->asc, tape->ascq);
-#endif /* IDETAPE_DEBUG_LOG */
-
-       /* Correct pc->actually_transferred by asking the tape.  */
-       if (test_bit(PC_DMA_ERROR, &pc->flags)) {
-               pc->actually_transferred = pc->request_transfer -
-                       tape->tape_block_size *
-                       ntohl(get_unaligned((u32 *)&sense[3]));
-               idetape_update_buffers(pc);
+
+       debug_log(DBG_ERR, "pc = %x, sense key = %x, asc = %x, ascq = %x\n",
+                pc->c[0], tape->sense_key, tape->asc, tape->ascq);
+
+       /* Correct pc->xferred by asking the tape.       */
+       if (pc->flags & PC_FLAG_DMA_ERROR) {
+               pc->xferred = pc->req_xfer -
+                       tape->blk_size *
+                       get_unaligned_be32(&sense[3]);
+               idetape_update_buffers(drive, pc);
        }
 
        /*
@@ -896,200 +422,74 @@ static void idetape_analyze_error(ide_drive_t *drive, u8 *sense)
         * with sense key=5, asc=0x22, ascq=0, let it slide.  Some drives
         * (i.e. Seagate STT3401A Travan) don't support 0-length read/writes.
         */
-       if ((pc->c[0] == IDETAPE_READ_CMD || pc->c[0] == IDETAPE_WRITE_CMD)
+       if ((pc->c[0] == READ_6 || pc->c[0] == WRITE_6)
            /* length == 0 */
            && pc->c[4] == 0 && pc->c[3] == 0 && pc->c[2] == 0) {
                if (tape->sense_key == 5) {
                        /* don't report an error, everything's ok */
                        pc->error = 0;
                        /* don't retry read/write */
-                       set_bit(PC_ABORT, &pc->flags);
+                       pc->flags |= PC_FLAG_ABORT;
                }
        }
-       if (pc->c[0] == IDETAPE_READ_CMD && (sense[2] & 0x80)) {
+       if (pc->c[0] == READ_6 && (sense[2] & 0x80)) {
                pc->error = IDETAPE_ERROR_FILEMARK;
-               set_bit(PC_ABORT, &pc->flags);
+               pc->flags |= PC_FLAG_ABORT;
        }
-       if (pc->c[0] == IDETAPE_WRITE_CMD) {
+       if (pc->c[0] == WRITE_6) {
                if ((sense[2] & 0x40) || (tape->sense_key == 0xd
                     && tape->asc == 0x0 && tape->ascq == 0x2)) {
                        pc->error = IDETAPE_ERROR_EOD;
-                       set_bit(PC_ABORT, &pc->flags);
+                       pc->flags |= PC_FLAG_ABORT;
                }
        }
-       if (pc->c[0] == IDETAPE_READ_CMD || pc->c[0] == IDETAPE_WRITE_CMD) {
+       if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) {
                if (tape->sense_key == 8) {
                        pc->error = IDETAPE_ERROR_EOD;
-                       set_bit(PC_ABORT, &pc->flags);
+                       pc->flags |= PC_FLAG_ABORT;
                }
-               if (!test_bit(PC_ABORT, &pc->flags) &&
-                   pc->actually_transferred)
+               if (!(pc->flags & PC_FLAG_ABORT) &&
+                   pc->xferred)
                        pc->retries = IDETAPE_MAX_PC_RETRIES + 1;
        }
 }
 
-/*
- * idetape_active_next_stage will declare the next stage as "active".
- */
-static void idetape_active_next_stage (ide_drive_t *drive)
+/* Free data buffers completely. */
+static void ide_tape_kfree_buffer(idetape_tape_t *tape)
 {
-       idetape_tape_t *tape = drive->driver_data;
-       idetape_stage_t *stage = tape->next_stage;
-       struct request *rq = &stage->rq;
+       struct idetape_bh *prev_bh, *bh = tape->merge_bh;
 
-#if IDETAPE_DEBUG_LOG
-       if (tape->debug_level >= 4)
-               printk(KERN_INFO "ide-tape: Reached idetape_active_next_stage\n");
-#endif /* IDETAPE_DEBUG_LOG */
-       if (stage == NULL) {
-               printk(KERN_ERR "ide-tape: bug: Trying to activate a non existing stage\n");
-               return;
-       }
+       while (bh) {
+               u32 size = bh->b_size;
 
-       rq->rq_disk = tape->disk;
-       rq->buffer = NULL;
-       rq->special = (void *)stage->bh;
-       tape->active_data_request = rq;
-       tape->active_stage = stage;
-       tape->next_stage = stage->next;
-}
+               while (size) {
+                       unsigned int order = fls(size >> PAGE_SHIFT)-1;
 
-/*
- *     idetape_increase_max_pipeline_stages is a part of the feedback
- *     loop which tries to find the optimum number of stages. In the
- *     feedback loop, we are starting from a minimum maximum number of
- *     stages, and if we sense that the pipeline is empty, we try to
- *     increase it, until we reach the user compile time memory limit.
- */
-static void idetape_increase_max_pipeline_stages (ide_drive_t *drive)
-{
-       idetape_tape_t *tape = drive->driver_data;
-       int increase = (tape->max_pipeline - tape->min_pipeline) / 10;
-       
-#if IDETAPE_DEBUG_LOG
-       if (tape->debug_level >= 4)
-               printk (KERN_INFO "ide-tape: Reached idetape_increase_max_pipeline_stages\n");
-#endif /* IDETAPE_DEBUG_LOG */
-
-       tape->max_stages += max(increase, 1);
-       tape->max_stages = max(tape->max_stages, tape->min_pipeline);
-       tape->max_stages = min(tape->max_stages, tape->max_pipeline);
-}
+                       if (bh->b_data)
+                               free_pages((unsigned long)bh->b_data, order);
 
-/*
- *     idetape_kfree_stage calls kfree to completely free a stage, along with
- *     its related buffers.
- */
-static void __idetape_kfree_stage (idetape_stage_t *stage)
-{
-       struct idetape_bh *prev_bh, *bh = stage->bh;
-       int size;
-
-       while (bh != NULL) {
-               if (bh->b_data != NULL) {
-                       size = (int) bh->b_size;
-                       while (size > 0) {
-                               free_page((unsigned long) bh->b_data);
-                               size -= PAGE_SIZE;
-                               bh->b_data += PAGE_SIZE;
-                       }
+                       size &= (order-1);
+                       bh->b_data += (1 << order) * PAGE_SIZE;
                }
                prev_bh = bh;
                bh = bh->b_reqnext;
                kfree(prev_bh);
        }
-       kfree(stage);
-}
-
-static void idetape_kfree_stage (idetape_tape_t *tape, idetape_stage_t *stage)
-{
-       __idetape_kfree_stage(stage);
-}
-
-/*
- *     idetape_remove_stage_head removes tape->first_stage from the pipeline.
- *     The caller should avoid race conditions.
- */
-static void idetape_remove_stage_head (ide_drive_t *drive)
-{
-       idetape_tape_t *tape = drive->driver_data;
-       idetape_stage_t *stage;
-       
-#if IDETAPE_DEBUG_LOG
-       if (tape->debug_level >= 4)
-               printk(KERN_INFO "ide-tape: Reached idetape_remove_stage_head\n");
-#endif /* IDETAPE_DEBUG_LOG */
-       if (tape->first_stage == NULL) {
-               printk(KERN_ERR "ide-tape: bug: tape->first_stage is NULL\n");
-               return;
-       }
-       if (tape->active_stage == tape->first_stage) {
-               printk(KERN_ERR "ide-tape: bug: Trying to free our active pipeline stage\n");
-               return;
-       }
-       stage = tape->first_stage;
-       tape->first_stage = stage->next;
-       idetape_kfree_stage(tape, stage);
-       tape->nr_stages--;
-       if (tape->first_stage == NULL) {
-               tape->last_stage = NULL;
-               if (tape->next_stage != NULL)
-                       printk(KERN_ERR "ide-tape: bug: tape->next_stage != NULL\n");
-               if (tape->nr_stages)
-                       printk(KERN_ERR "ide-tape: bug: nr_stages should be 0 now\n");
-       }
-}
-
-/*
- * This will free all the pipeline stages starting from new_last_stage->next
- * to the end of the list, and point tape->last_stage to new_last_stage.
- */
-static void idetape_abort_pipeline(ide_drive_t *drive,
-                                  idetape_stage_t *new_last_stage)
-{
-       idetape_tape_t *tape = drive->driver_data;
-       idetape_stage_t *stage = new_last_stage->next;
-       idetape_stage_t *nstage;
-
-#if IDETAPE_DEBUG_LOG
-       if (tape->debug_level >= 4)
-               printk(KERN_INFO "ide-tape: %s: idetape_abort_pipeline called\n", tape->name);
-#endif
-       while (stage) {
-               nstage = stage->next;
-               idetape_kfree_stage(tape, stage);
-               --tape->nr_stages;
-               --tape->nr_pending_stages;
-               stage = nstage;
-       }
-       if (new_last_stage)
-               new_last_stage->next = NULL;
-       tape->last_stage = new_last_stage;
-       tape->next_stage = NULL;
 }
 
-/*
- *     idetape_end_request is used to finish servicing a request, and to
- *     insert a pending pipeline request into the main device queue.
- */
 static int idetape_end_request(ide_drive_t *drive, int uptodate, int nr_sects)
 {
-       struct request *rq = HWGROUP(drive)->rq;
+       struct request *rq = drive->hwif->rq;
        idetape_tape_t *tape = drive->driver_data;
        unsigned long flags;
        int error;
-       int remove_stage = 0;
-       idetape_stage_t *active_stage;
 
-#if IDETAPE_DEBUG_LOG
-        if (tape->debug_level >= 4)
-       printk(KERN_INFO "ide-tape: Reached idetape_end_request\n");
-#endif /* IDETAPE_DEBUG_LOG */
+       debug_log(DBG_PROCS, "Enter %s\n", __func__);
 
        switch (uptodate) {
-               case 0: error = IDETAPE_ERROR_GENERAL; break;
-               case 1: error = 0; break;
-               default: error = uptodate;
+       case 0: error = IDETAPE_ERROR_GENERAL; break;
+       case 1: error = 0; break;
+       default: error = uptodate;
        }
        rq->errors = error;
        if (error)
@@ -1100,450 +500,181 @@ static int idetape_end_request(ide_drive_t *drive, int uptodate, int nr_sects)
                return 0;
        }
 
-       spin_lock_irqsave(&tape->spinlock, flags);
-
-       /* The request was a pipelined data transfer request */
-       if (tape->active_data_request == rq) {
-               active_stage = tape->active_stage;
-               tape->active_stage = NULL;
-               tape->active_data_request = NULL;
-               tape->nr_pending_stages--;
-               if (rq->cmd[0] & REQ_IDETAPE_WRITE) {
-                       remove_stage = 1;
-                       if (error) {
-                               set_bit(IDETAPE_PIPELINE_ERROR, &tape->flags);
-                               if (error == IDETAPE_ERROR_EOD)
-                                       idetape_abort_pipeline(drive, active_stage);
-                       }
-               } else if (rq->cmd[0] & REQ_IDETAPE_READ) {
-                       if (error == IDETAPE_ERROR_EOD) {
-                               set_bit(IDETAPE_PIPELINE_ERROR, &tape->flags);
-                               idetape_abort_pipeline(drive, active_stage);
-                       }
-               }
-               if (tape->next_stage != NULL) {
-                       idetape_active_next_stage(drive);
-
-                       /*
-                        * Insert the next request into the request queue.
-                        */
-                       (void) ide_do_drive_cmd(drive, tape->active_data_request, ide_end);
-               } else if (!error) {
-                               idetape_increase_max_pipeline_stages(drive);
-               }
-       }
+       spin_lock_irqsave(&tape->lock, flags);
+
        ide_end_drive_cmd(drive, 0, 0);
-//     blkdev_dequeue_request(rq);
-//     drive->rq = NULL;
-//     end_that_request_last(rq);
-
-       if (remove_stage)
-               idetape_remove_stage_head(drive);
-       if (tape->active_data_request == NULL)
-               clear_bit(IDETAPE_PIPELINE_ACTIVE, &tape->flags);
-       spin_unlock_irqrestore(&tape->spinlock, flags);
+
+       spin_unlock_irqrestore(&tape->lock, flags);
        return 0;
 }
 
-static ide_startstop_t idetape_request_sense_callback (ide_drive_t *drive)
+static void ide_tape_handle_dsc(ide_drive_t *);
+
+static void ide_tape_callback(ide_drive_t *drive, int dsc)
 {
        idetape_tape_t *tape = drive->driver_data;
+       struct ide_atapi_pc *pc = drive->pc;
+       int uptodate = pc->error ? 0 : 1;
 
-#if IDETAPE_DEBUG_LOG
-       if (tape->debug_level >= 4)
-               printk(KERN_INFO "ide-tape: Reached idetape_request_sense_callback\n");
-#endif /* IDETAPE_DEBUG_LOG */
-       if (!tape->pc->error) {
-               idetape_analyze_error(drive, tape->pc->buffer);
-               idetape_end_request(drive, 1, 0);
-       } else {
-               printk(KERN_ERR "ide-tape: Error in REQUEST SENSE itself - Aborting request!\n");
-               idetape_end_request(drive, 0, 0);
-       }
-       return ide_stopped;
-}
+       debug_log(DBG_PROCS, "Enter %s\n", __func__);
 
-static void idetape_create_request_sense_cmd (idetape_pc_t *pc)
-{
-       idetape_init_pc(pc);    
-       pc->c[0] = IDETAPE_REQUEST_SENSE_CMD;
-       pc->c[4] = 20;
-       pc->request_transfer = 20;
-       pc->callback = &idetape_request_sense_callback;
-}
+       if (dsc)
+               ide_tape_handle_dsc(drive);
 
-static void idetape_init_rq(struct request *rq, u8 cmd)
-{
-       memset(rq, 0, sizeof(*rq));
-       rq->cmd_type = REQ_TYPE_SPECIAL;
-       rq->cmd[0] = cmd;
-}
+       if (tape->failed_pc == pc)
+               tape->failed_pc = NULL;
 
-/*
- *     idetape_queue_pc_head generates a new packet command request in front
- *     of the request queue, before the current request, so that it will be
- *     processed immediately, on the next pass through the driver.
- *
- *     idetape_queue_pc_head is called from the request handling part of
- *     the driver (the "bottom" part). Safe storage for the request should
- *     be allocated with idetape_next_pc_storage and idetape_next_rq_storage
- *     before calling idetape_queue_pc_head.
- *
- *     Memory for those requests is pre-allocated at initialization time, and
- *     is limited to IDETAPE_PC_STACK requests. We assume that we have enough
- *     space for the maximum possible number of inter-dependent packet commands.
- *
- *     The higher level of the driver - The ioctl handler and the character
- *     device handling functions should queue request to the lower level part
- *     and wait for their completion using idetape_queue_pc_tail or
- *     idetape_queue_rw_tail.
- */
-static void idetape_queue_pc_head (ide_drive_t *drive, idetape_pc_t *pc,struct request *rq)
-{
-       struct ide_tape_obj *tape = drive->driver_data;
+       if (pc->c[0] == REQUEST_SENSE) {
+               if (uptodate)
+                       idetape_analyze_error(drive, pc->buf);
+               else
+                       printk(KERN_ERR "ide-tape: Error in REQUEST SENSE "
+                                       "itself - Aborting request!\n");
+       } else if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) {
+               struct request *rq = drive->hwif->rq;
+               int blocks = pc->xferred / tape->blk_size;
+
+               tape->avg_size += blocks * tape->blk_size;
+
+               if (time_after_eq(jiffies, tape->avg_time + HZ)) {
+                       tape->avg_speed = tape->avg_size * HZ /
+                               (jiffies - tape->avg_time) / 1024;
+                       tape->avg_size = 0;
+                       tape->avg_time = jiffies;
+               }
+
+               tape->first_frame += blocks;
+               rq->current_nr_sectors -= blocks;
+
+               if (pc->error)
+                       uptodate = pc->error;
+       } else if (pc->c[0] == READ_POSITION && uptodate) {
+               u8 *readpos = pc->buf;
 
-       idetape_init_rq(rq, REQ_IDETAPE_PC1);
-       rq->buffer = (char *) pc;
-       rq->rq_disk = tape->disk;
-       (void) ide_do_drive_cmd(drive, rq, ide_preempt);
-}
+               debug_log(DBG_SENSE, "BOP - %s\n",
+                               (readpos[0] & 0x80) ? "Yes" : "No");
+               debug_log(DBG_SENSE, "EOP - %s\n",
+                               (readpos[0] & 0x40) ? "Yes" : "No");
 
-/*
- *     idetape_retry_pc is called when an error was detected during the
- *     last packet command. We queue a request sense packet command in
- *     the head of the request list.
- */
-static ide_startstop_t idetape_retry_pc (ide_drive_t *drive)
-{
-       idetape_tape_t *tape = drive->driver_data;
-       idetape_pc_t *pc;
-       struct request *rq;
+               if (readpos[0] & 0x4) {
+                       printk(KERN_INFO "ide-tape: Block location is unknown"
+                                        "to the tape\n");
+                       clear_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags);
+                       uptodate = 0;
+               } else {
+                       debug_log(DBG_SENSE, "Block Location - %u\n",
+                                       be32_to_cpup((__be32 *)&readpos[4]));
 
-       (void)drive->hwif->INB(IDE_ERROR_REG);
-       pc = idetape_next_pc_storage(drive);
-       rq = idetape_next_rq_storage(drive);
-       idetape_create_request_sense_cmd(pc);
-       set_bit(IDETAPE_IGNORE_DSC, &tape->flags);
-       idetape_queue_pc_head(drive, pc, rq);
-       return ide_stopped;
+                       tape->partition = readpos[1];
+                       tape->first_frame = be32_to_cpup((__be32 *)&readpos[4]);
+                       set_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags);
+               }
+       }
+
+       idetape_end_request(drive, uptodate, 0);
 }
 
 /*
- *     idetape_postpone_request postpones the current request so that
- *     ide.c will be able to service requests from another device on
- *     the same hwgroup while we are polling for DSC.
+ * Postpone the current request so that ide.c will be able to service requests
+ * from another device on the same port while we are polling for DSC.
  */
-static void idetape_postpone_request (ide_drive_t *drive)
+static void idetape_postpone_request(ide_drive_t *drive)
 {
        idetape_tape_t *tape = drive->driver_data;
 
-#if IDETAPE_DEBUG_LOG
-       if (tape->debug_level >= 4)
-               printk(KERN_INFO "ide-tape: idetape_postpone_request\n");
-#endif
-       tape->postponed_rq = HWGROUP(drive)->rq;
-       ide_stall_queue(drive, tape->dsc_polling_frequency);
+       debug_log(DBG_PROCS, "Enter %s\n", __func__);
+
+       tape->postponed_rq = drive->hwif->rq;
+
+       ide_stall_queue(drive, tape->dsc_poll_freq);
 }
 
-/*
- *     idetape_pc_intr is the usual interrupt handler which will be called
- *     during a packet command. We will transfer some of the data (as
- *     requested by the drive) and will re-point interrupt handler to us.
- *     When data transfer is finished, we will act according to the
- *     algorithm described before idetape_issue_packet_command.
- *
- */
-static ide_startstop_t idetape_pc_intr (ide_drive_t *drive)
+static void ide_tape_handle_dsc(ide_drive_t *drive)
 {
-       ide_hwif_t *hwif = drive->hwif;
        idetape_tape_t *tape = drive->driver_data;
-       idetape_pc_t *pc = tape->pc;
-       unsigned int temp;
-#if SIMULATE_ERRORS
-       static int error_sim_count = 0;
-#endif
-       u16 bcount;
-       u8 stat, ireason;
-
-#if IDETAPE_DEBUG_LOG
-       if (tape->debug_level >= 4)
-               printk(KERN_INFO "ide-tape: Reached idetape_pc_intr "
-                               "interrupt handler\n");
-#endif /* IDETAPE_DEBUG_LOG */ 
-
-       /* Clear the interrupt */
-       stat = hwif->INB(IDE_STATUS_REG);
-
-       if (test_bit(PC_DMA_IN_PROGRESS, &pc->flags)) {
-               if (hwif->ide_dma_end(drive) || (stat & ERR_STAT)) {
-                       /*
-                        * A DMA error is sometimes expected. For example,
-                        * if the tape is crossing a filemark during a
-                        * READ command, it will issue an irq and position
-                        * itself before the filemark, so that only a partial
-                        * data transfer will occur (which causes the DMA
-                        * error). In that case, we will later ask the tape
-                        * how much bytes of the original request were
-                        * actually transferred (we can't receive that
-                        * information from the DMA engine on most chipsets).
-                        */
-
-                       /*
-                        * On the contrary, a DMA error is never expected;
-                        * it usually indicates a hardware error or abort.
-                        * If the tape crosses a filemark during a READ
-                        * command, it will issue an irq and position itself
-                        * after the filemark (not before). Only a partial
-                        * data transfer will occur, but no DMA error.
-                        * (AS, 19 Apr 2001)
-                        */
-                       set_bit(PC_DMA_ERROR, &pc->flags);
-               } else {
-                       pc->actually_transferred = pc->request_transfer;
-                       idetape_update_buffers(pc);
-               }
-#if IDETAPE_DEBUG_LOG
-               if (tape->debug_level >= 4)
-                       printk(KERN_INFO "ide-tape: DMA finished\n");
-#endif /* IDETAPE_DEBUG_LOG */
-       }
 
-       /* No more interrupts */
-       if ((stat & DRQ_STAT) == 0) {
-#if IDETAPE_DEBUG_LOG
-               if (tape->debug_level >= 2)
-                       printk(KERN_INFO "ide-tape: Packet command completed, %d bytes transferred\n", pc->actually_transferred);
-#endif /* IDETAPE_DEBUG_LOG */
-               clear_bit(PC_DMA_IN_PROGRESS, &pc->flags);
-
-               local_irq_enable();
-
-#if SIMULATE_ERRORS
-               if ((pc->c[0] == IDETAPE_WRITE_CMD ||
-                    pc->c[0] == IDETAPE_READ_CMD) &&
-                   (++error_sim_count % 100) == 0) {
-                       printk(KERN_INFO "ide-tape: %s: simulating error\n",
-                               tape->name);
-                       stat |= ERR_STAT;
-               }
-#endif
-               if ((stat & ERR_STAT) && pc->c[0] == IDETAPE_REQUEST_SENSE_CMD)
-                       stat &= ~ERR_STAT;
-               if ((stat & ERR_STAT) || test_bit(PC_DMA_ERROR, &pc->flags)) {
-                       /* Error detected */
-#if IDETAPE_DEBUG_LOG
-                       if (tape->debug_level >= 1)
-                               printk(KERN_INFO "ide-tape: %s: I/O error\n",
-                                       tape->name);
-#endif /* IDETAPE_DEBUG_LOG */
-                       if (pc->c[0] == IDETAPE_REQUEST_SENSE_CMD) {
-                               printk(KERN_ERR "ide-tape: I/O error in request sense command\n");
-                               return ide_do_reset(drive);
-                       }
-#if IDETAPE_DEBUG_LOG
-                       if (tape->debug_level >= 1)
-                               printk(KERN_INFO "ide-tape: [cmd %x]: check condition\n", pc->c[0]);
-#endif
-                       /* Retry operation */
-                       return idetape_retry_pc(drive);
-               }
-               pc->error = 0;
-               if (test_bit(PC_WAIT_FOR_DSC, &pc->flags) &&
-                   (stat & SEEK_STAT) == 0) {
-                       /* Media access command */
-                       tape->dsc_polling_start = jiffies;
-                       tape->dsc_polling_frequency = IDETAPE_DSC_MA_FAST;
-                       tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT;
-                       /* Allow ide.c to handle other requests */
-                       idetape_postpone_request(drive);
-                       return ide_stopped;
-               }
-               if (tape->failed_pc == pc)
-                       tape->failed_pc = NULL;
-               /* Command finished - Call the callback function */
-               return pc->callback(drive);
-       }
-       if (test_and_clear_bit(PC_DMA_IN_PROGRESS, &pc->flags)) {
-               printk(KERN_ERR "ide-tape: The tape wants to issue more "
-                               "interrupts in DMA mode\n");
-               printk(KERN_ERR "ide-tape: DMA disabled, reverting to PIO\n");
-               ide_dma_off(drive);
-               return ide_do_reset(drive);
-       }
-       /* Get the number of bytes to transfer on this interrupt. */
-       bcount = (hwif->INB(IDE_BCOUNTH_REG) << 8) |
-                 hwif->INB(IDE_BCOUNTL_REG);
+       /* Media access command */
+       tape->dsc_polling_start = jiffies;
+       tape->dsc_poll_freq = IDETAPE_DSC_MA_FAST;
+       tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT;
+       /* Allow ide.c to handle other requests */
+       idetape_postpone_request(drive);
+}
 
-       ireason = hwif->INB(IDE_IREASON_REG);
+static int ide_tape_io_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc,
+                               unsigned int bcount, int write)
+{
+       if (write)
+               idetape_output_buffers(drive, pc, bcount);
+       else
+               idetape_input_buffers(drive, pc, bcount);
 
-       if (ireason & CD) {
-               printk(KERN_ERR "ide-tape: CoD != 0 in idetape_pc_intr\n");
-               return ide_do_reset(drive);
-       }
-       if (((ireason & IO) == IO) == test_bit(PC_WRITING, &pc->flags)) {
-               /* Hopefully, we will never get here */
-               printk(KERN_ERR "ide-tape: We wanted to %s, ",
-                               (ireason & IO) ? "Write" : "Read");
-               printk(KERN_ERR "ide-tape: but the tape wants us to %s !\n",
-                               (ireason & IO) ? "Read" : "Write");
-               return ide_do_reset(drive);
-       }
-       if (!test_bit(PC_WRITING, &pc->flags)) {
-               /* Reading - Check that we have enough space */
-               temp = pc->actually_transferred + bcount;
-               if (temp > pc->request_transfer) {
-                       if (temp > pc->buffer_size) {
-                               printk(KERN_ERR "ide-tape: The tape wants to send us more data than expected - discarding data\n");
-                               idetape_discard_data(drive, bcount);
-                               ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL);
-                               return ide_started;
-                       }
-#if IDETAPE_DEBUG_LOG
-                       if (tape->debug_level >= 2)
-                               printk(KERN_NOTICE "ide-tape: The tape wants to send us more data than expected - allowing transfer\n");
-#endif /* IDETAPE_DEBUG_LOG */
-               }
-       }
-       if (test_bit(PC_WRITING, &pc->flags)) {
-               if (pc->bh != NULL)
-                       idetape_output_buffers(drive, pc, bcount);
-               else
-                       /* Write the current buffer */
-                       hwif->atapi_output_bytes(drive, pc->current_position,
-                                                bcount);
-       } else {
-               if (pc->bh != NULL)
-                       idetape_input_buffers(drive, pc, bcount);
-               else
-                       /* Read the current buffer */
-                       hwif->atapi_input_bytes(drive, pc->current_position,
-                                               bcount);
-       }
-       /* Update the current position */
-       pc->actually_transferred += bcount;
-       pc->current_position += bcount;
-#if IDETAPE_DEBUG_LOG
-       if (tape->debug_level >= 2)
-               printk(KERN_INFO "ide-tape: [cmd %x] transferred %d bytes "
-                                "on that interrupt\n", pc->c[0], bcount);
-#endif
-       /* And set the interrupt handler again */
-       ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL);
-       return ide_started;
+       return bcount;
 }
 
 /*
- *     Packet Command Interface
+ * Packet Command Interface
  *
- *     The current Packet Command is available in tape->pc, and will not
- *     change until we finish handling it. Each packet command is associated
- *     with a callback function that will be called when the command is
- *     finished.
+ * The current Packet Command is available in drive->pc, and will not change
+ * until we finish handling it. Each packet command is associated with a
+ * callback function that will be called when the command is finished.
  *
- *     The handling will be done in three stages:
+ * The handling will be done in three stages:
  *
- *     1.      idetape_issue_packet_command will send the packet command to the
- *             drive, and will set the interrupt handler to idetape_pc_intr.
+ * 1. idetape_issue_pc will send the packet command to the drive, and will set
+ * the interrupt handler to ide_pc_intr.
  *
- *     2.      On each interrupt, idetape_pc_intr will be called. This step
- *             will be repeated until the device signals us that no more
- *             interrupts will be issued.
+ * 2. On each interrupt, ide_pc_intr will be called. This step will be
+ * repeated until the device signals us that no more interrupts will be issued.
  *
- *     3.      ATAPI Tape media access commands have immediate status with a
- *             delayed process. In case of a successful initiation of a
- *             media access packet command, the DSC bit will be set when the
- *             actual execution of the command is finished. 
- *             Since the tape drive will not issue an interrupt, we have to
- *             poll for this event. In this case, we define the request as
- *             "low priority request" by setting rq_status to
- *             IDETAPE_RQ_POSTPONED,   set a timer to poll for DSC and exit
- *             the driver.
+ * 3. ATAPI Tape media access commands have immediate status with a delayed
+ * process. In case of a successful initiation of a media access packet command,
+ * the DSC bit will be set when the actual execution of the command is finished.
+ * Since the tape drive will not issue an interrupt, we have to poll for this
+ * event. In this case, we define the request as "low priority request" by
+ * setting rq_status to IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and
+ * exit the driver.
  *
- *             ide.c will then give higher priority to requests which
- *             originate from the other device, until will change rq_status
- *             to RQ_ACTIVE.
+ * ide.c will then give higher priority to requests which originate from the
+ * other device, until will change rq_status to RQ_ACTIVE.
  *
- *     4.      When the packet command is finished, it will be checked for errors.
+ * 4. When the packet command is finished, it will be checked for errors.
  *
- *     5.      In case an error was found, we queue a request sense packet
- *             command in front of the request queue and retry the operation
- *             up to IDETAPE_MAX_PC_RETRIES times.
- *
- *     6.      In case no error was found, or we decided to give up and not
- *             to retry again, the callback function will be called and then
- *             we will handle the next request.
+ * 5. In case an error was found, we queue a request sense packet command in
+ * front of the request queue and retry the operation up to
+ * IDETAPE_MAX_PC_RETRIES times.
  *
+ * 6. In case no error was found, or we decided to give up and not to retry
+ * again, the callback function will be called and then we will handle the next
+ * request.
  */
-static ide_startstop_t idetape_transfer_pc(ide_drive_t *drive)
-{
-       ide_hwif_t *hwif = drive->hwif;
-       idetape_tape_t *tape = drive->driver_data;
-       idetape_pc_t *pc = tape->pc;
-       int retries = 100;
-       ide_startstop_t startstop;
-       u8 ireason;
-
-       if (ide_wait_stat(&startstop,drive,DRQ_STAT,BUSY_STAT,WAIT_READY)) {
-               printk(KERN_ERR "ide-tape: Strange, packet command initiated yet DRQ isn't asserted\n");
-               return startstop;
-       }
-       ireason = hwif->INB(IDE_IREASON_REG);
-       while (retries-- && ((ireason & CD) == 0 || (ireason & IO))) {
-               printk(KERN_ERR "ide-tape: (IO,CoD != (0,1) while issuing "
-                               "a packet command, retrying\n");
-               udelay(100);
-               ireason = hwif->INB(IDE_IREASON_REG);
-               if (retries == 0) {
-                       printk(KERN_ERR "ide-tape: (IO,CoD != (0,1) while "
-                                       "issuing a packet command, ignoring\n");
-                       ireason |= CD;
-                       ireason &= ~IO;
-               }
-       }
-       if ((ireason & CD) == 0 || (ireason & IO)) {
-               printk(KERN_ERR "ide-tape: (IO,CoD) != (0,1) while issuing "
-                               "a packet command\n");
-               return ide_do_reset(drive);
-       }
-       /* Set the interrupt routine */
-       ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL);
-#ifdef CONFIG_BLK_DEV_IDEDMA
-       /* Begin DMA, if necessary */
-       if (test_bit(PC_DMA_IN_PROGRESS, &pc->flags))
-               hwif->dma_start(drive);
-#endif
-       /* Send the actual packet */
-       HWIF(drive)->atapi_output_bytes(drive, pc->c, 12);
-       return ide_started;
-}
 
-static ide_startstop_t idetape_issue_packet_command (ide_drive_t *drive, idetape_pc_t *pc)
+static ide_startstop_t idetape_issue_pc(ide_drive_t *drive,
+               struct ide_atapi_pc *pc)
 {
-       ide_hwif_t *hwif = drive->hwif;
        idetape_tape_t *tape = drive->driver_data;
-       int dma_ok = 0;
-       u16 bcount;
 
-       if (tape->pc->c[0] == IDETAPE_REQUEST_SENSE_CMD &&
-           pc->c[0] == IDETAPE_REQUEST_SENSE_CMD) {
+       if (drive->pc->c[0] == REQUEST_SENSE &&
+           pc->c[0] == REQUEST_SENSE) {
                printk(KERN_ERR "ide-tape: possible ide-tape.c bug - "
                        "Two request sense in serial were issued\n");
        }
 
-       if (tape->failed_pc == NULL && pc->c[0] != IDETAPE_REQUEST_SENSE_CMD)
+       if (tape->failed_pc == NULL && pc->c[0] != REQUEST_SENSE)
                tape->failed_pc = pc;
+
        /* Set the current packet command */
-       tape->pc = pc;
+       drive->pc = pc;
 
        if (pc->retries > IDETAPE_MAX_PC_RETRIES ||
-           test_bit(PC_ABORT, &pc->flags)) {
+               (pc->flags & PC_FLAG_ABORT)) {
                /*
-                *      We will "abort" retrying a packet command in case
-                *      a legitimate error code was received (crossing a
-                *      filemark, or end of the media, for example).
+                * We will "abort" retrying a packet command in case legitimate
+                * error code was received (crossing a filemark, or end of the
+                * media, for example).
                 */
-               if (!test_bit(PC_ABORT, &pc->flags)) {
-                       if (!(pc->c[0] == IDETAPE_TEST_UNIT_READY_CMD &&
+               if (!(pc->flags & PC_FLAG_ABORT)) {
+                       if (!(pc->c[0] == TEST_UNIT_READY &&
                              tape->sense_key == 2 && tape->asc == 4 &&
                             (tape->ascq == 1 || tape->ascq == 8))) {
                                printk(KERN_ERR "ide-tape: %s: I/O error, "
@@ -1557,68 +688,24 @@ static ide_startstop_t idetape_issue_packet_command (ide_drive_t *drive, idetape
                        pc->error = IDETAPE_ERROR_GENERAL;
                }
                tape->failed_pc = NULL;
-               return pc->callback(drive);
+               drive->pc_callback(drive, 0);
+               return ide_stopped;
        }
-#if IDETAPE_DEBUG_LOG
-       if (tape->debug_level >= 2)
-               printk(KERN_INFO "ide-tape: Retry number - %d, cmd = %02X\n", pc->retries, pc->c[0]);
-#endif /* IDETAPE_DEBUG_LOG */
+       debug_log(DBG_SENSE, "Retry #%d, cmd = %02X\n", pc->retries, pc->c[0]);
 
        pc->retries++;
-       /* We haven't transferred any data yet */
-       pc->actually_transferred = 0;
-       pc->current_position = pc->buffer;
-       /* Request to transfer the entire buffer at once */
-       bcount = pc->request_transfer;
-
-       if (test_and_clear_bit(PC_DMA_ERROR, &pc->flags)) {
-               printk(KERN_WARNING "ide-tape: DMA disabled, "
-                               "reverting to PIO\n");
-               ide_dma_off(drive);
-       }
-       if (test_bit(PC_DMA_RECOMMENDED, &pc->flags) && drive->using_dma)
-               dma_ok = !hwif->dma_setup(drive);
-
-       ide_pktcmd_tf_load(drive, IDE_TFLAG_NO_SELECT_MASK |
-                          IDE_TFLAG_OUT_DEVICE, bcount, dma_ok);
-
-       if (dma_ok)                     /* Will begin DMA later */
-               set_bit(PC_DMA_IN_PROGRESS, &pc->flags);
-       if (test_bit(IDETAPE_DRQ_INTERRUPT, &tape->flags)) {
-               ide_execute_command(drive, WIN_PACKETCMD, &idetape_transfer_pc,
-                                   IDETAPE_WAIT_CMD, NULL);
-               return ide_started;
-       } else {
-               hwif->OUTB(WIN_PACKETCMD, IDE_COMMAND_REG);
-               return idetape_transfer_pc(drive);
-       }
-}
-
-/*
- *     General packet command callback function.
- */
-static ide_startstop_t idetape_pc_callback (ide_drive_t *drive)
-{
-       idetape_tape_t *tape = drive->driver_data;
-       
-#if IDETAPE_DEBUG_LOG
-       if (tape->debug_level >= 4)
-               printk(KERN_INFO "ide-tape: Reached idetape_pc_callback\n");
-#endif /* IDETAPE_DEBUG_LOG */
 
-       idetape_end_request(drive, tape->pc->error ? 0 : 1, 0);
-       return ide_stopped;
+       return ide_issue_pc(drive);
 }
 
-/*
- *     A mode sense command is used to "sense" tape parameters.
- */
-static void idetape_create_mode_sense_cmd (idetape_pc_t *pc, u8 page_code)
+/* A mode sense command is used to "sense" tape parameters. */
+static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code)
 {
-       idetape_init_pc(pc);
-       pc->c[0] = IDETAPE_MODE_SENSE_CMD;
+       ide_init_pc(pc);
+       pc->c[0] = MODE_SENSE;
        if (page_code != IDETAPE_BLOCK_DESCRIPTOR)
-               pc->c[1] = 8;   /* DBD = 1 - Don't return block descriptors */
+               /* DBD = 1 - Don't return block descriptors */
+               pc->c[1] = 8;
        pc->c[2] = page_code;
        /*
         * Changed pc->c[3] to 0 (255 will at best return unused info).
@@ -1628,217 +715,102 @@ static void idetape_create_mode_sense_cmd (idetape_pc_t *pc, u8 page_code)
         * and return an error when 255 is used.
         */
        pc->c[3] = 0;
-       pc->c[4] = 255;         /* (We will just discard data in that case) */
+       /* We will just discard data in that case */
+       pc->c[4] = 255;
        if (page_code == IDETAPE_BLOCK_DESCRIPTOR)
-               pc->request_transfer = 12;
+               pc->req_xfer = 12;
        else if (page_code == IDETAPE_CAPABILITIES_PAGE)
-               pc->request_transfer = 24;
+               pc->req_xfer = 24;
        else
-               pc->request_transfer = 50;
-       pc->callback = &idetape_pc_callback;
-}
-
-static void calculate_speeds(ide_drive_t *drive)
-{
-       idetape_tape_t *tape = drive->driver_data;
-       int full = 125, empty = 75;
-
-       if (time_after(jiffies, tape->controlled_pipeline_head_time + 120 * HZ)) {
-               tape->controlled_previous_pipeline_head = tape->controlled_last_pipeline_head;
-               tape->controlled_previous_head_time = tape->controlled_pipeline_head_time;
-               tape->controlled_last_pipeline_head = tape->pipeline_head;
-               tape->controlled_pipeline_head_time = jiffies;
-       }
-       if (time_after(jiffies, tape->controlled_pipeline_head_time + 60 * HZ))
-               tape->controlled_pipeline_head_speed = (tape->pipeline_head - tape->controlled_last_pipeline_head) * 32 * HZ / (jiffies - tape->controlled_pipeline_head_time);
-       else if (time_after(jiffies, tape->controlled_previous_head_time))
-               tape->controlled_pipeline_head_speed = (tape->pipeline_head - tape->controlled_previous_pipeline_head) * 32 * HZ / (jiffies - tape->controlled_previous_head_time);
-
-       if (tape->nr_pending_stages < tape->max_stages /*- 1 */) {
-               /* -1 for read mode error recovery */
-               if (time_after(jiffies, tape->uncontrolled_previous_head_time + 10 * HZ)) {
-                       tape->uncontrolled_pipeline_head_time = jiffies;
-                       tape->uncontrolled_pipeline_head_speed = (tape->pipeline_head - tape->uncontrolled_previous_pipeline_head) * 32 * HZ / (jiffies - tape->uncontrolled_previous_head_time);
-               }
-       } else {
-               tape->uncontrolled_previous_head_time = jiffies;
-               tape->uncontrolled_previous_pipeline_head = tape->pipeline_head;
-               if (time_after(jiffies, tape->uncontrolled_pipeline_head_time + 30 * HZ)) {
-                       tape->uncontrolled_pipeline_head_time = jiffies;
-               }
-       }
-       tape->pipeline_head_speed = max(tape->uncontrolled_pipeline_head_speed, tape->controlled_pipeline_head_speed);
-       if (tape->speed_control == 0) {
-               tape->max_insert_speed = 5000;
-       } else if (tape->speed_control == 1) {
-               if (tape->nr_pending_stages >= tape->max_stages / 2)
-                       tape->max_insert_speed = tape->pipeline_head_speed +
-                               (1100 - tape->pipeline_head_speed) * 2 * (tape->nr_pending_stages - tape->max_stages / 2) / tape->max_stages;
-               else
-                       tape->max_insert_speed = 500 +
-                               (tape->pipeline_head_speed - 500) * 2 * tape->nr_pending_stages / tape->max_stages;
-               if (tape->nr_pending_stages >= tape->max_stages * 99 / 100)
-                       tape->max_insert_speed = 5000;
-       } else if (tape->speed_control == 2) {
-               tape->max_insert_speed = tape->pipeline_head_speed * empty / 100 +
-                       (tape->pipeline_head_speed * full / 100 - tape->pipeline_head_speed * empty / 100) * tape->nr_pending_stages / tape->max_stages;
-       } else
-               tape->max_insert_speed = tape->speed_control;
-       tape->max_insert_speed = max(tape->max_insert_speed, 500);
+               pc->req_xfer = 50;
 }
 
-static ide_startstop_t idetape_media_access_finished (ide_drive_t *drive)
+static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive)
 {
+       ide_hwif_t *hwif = drive->hwif;
        idetape_tape_t *tape = drive->driver_data;
-       idetape_pc_t *pc = tape->pc;
+       struct ide_atapi_pc *pc = drive->pc;
        u8 stat;
 
-       stat = drive->hwif->INB(IDE_STATUS_REG);
-       if (stat & SEEK_STAT) {
-               if (stat & ERR_STAT) {
+       stat = hwif->tp_ops->read_status(hwif);
+
+       if (stat & ATA_DSC) {
+               if (stat & ATA_ERR) {
                        /* Error detected */
-                       if (pc->c[0] != IDETAPE_TEST_UNIT_READY_CMD)
+                       if (pc->c[0] != TEST_UNIT_READY)
                                printk(KERN_ERR "ide-tape: %s: I/O error, ",
                                                tape->name);
                        /* Retry operation */
-                       return idetape_retry_pc(drive);
+                       ide_retry_pc(drive, tape->disk);
+                       return ide_stopped;
                }
                pc->error = 0;
-               if (tape->failed_pc == pc)
-                       tape->failed_pc = NULL;
        } else {
                pc->error = IDETAPE_ERROR_GENERAL;
                tape->failed_pc = NULL;
        }
-       return pc->callback(drive);
-}
-
-static ide_startstop_t idetape_rw_callback (ide_drive_t *drive)
-{
-       idetape_tape_t *tape = drive->driver_data;
-       struct request *rq = HWGROUP(drive)->rq;
-       int blocks = tape->pc->actually_transferred / tape->tape_block_size;
-
-       tape->avg_size += blocks * tape->tape_block_size;
-       tape->insert_size += blocks * tape->tape_block_size;
-       if (tape->insert_size > 1024 * 1024)
-               tape->measure_insert_time = 1;
-       if (tape->measure_insert_time) {
-               tape->measure_insert_time = 0;
-               tape->insert_time = jiffies;
-               tape->insert_size = 0;
-       }
-       if (time_after(jiffies, tape->insert_time))
-               tape->insert_speed = tape->insert_size / 1024 * HZ / (jiffies - tape->insert_time);
-       if (time_after_eq(jiffies, tape->avg_time + HZ)) {
-               tape->avg_speed = tape->avg_size * HZ / (jiffies - tape->avg_time) / 1024;
-               tape->avg_size = 0;
-               tape->avg_time = jiffies;
-       }
-
-#if IDETAPE_DEBUG_LOG  
-       if (tape->debug_level >= 4)
-               printk(KERN_INFO "ide-tape: Reached idetape_rw_callback\n");
-#endif /* IDETAPE_DEBUG_LOG */
-
-       tape->first_frame_position += blocks;
-       rq->current_nr_sectors -= blocks;
-
-       if (!tape->pc->error)
-               idetape_end_request(drive, 1, 0);
-       else
-               idetape_end_request(drive, tape->pc->error, 0);
+       drive->pc_callback(drive, 0);
        return ide_stopped;
 }
 
-static void idetape_create_read_cmd(idetape_tape_t *tape, idetape_pc_t *pc, unsigned int length, struct idetape_bh *bh)
+static void ide_tape_create_rw_cmd(idetape_tape_t *tape,
+                                  struct ide_atapi_pc *pc, struct request *rq,
+                                  u8 opcode)
 {
-       idetape_init_pc(pc);
-       pc->c[0] = IDETAPE_READ_CMD;
-       put_unaligned(htonl(length), (unsigned int *) &pc->c[1]);
-       pc->c[1] = 1;
-       pc->callback = &idetape_rw_callback;
-       pc->bh = bh;
-       atomic_set(&bh->b_count, 0);
-       pc->buffer = NULL;
-       pc->request_transfer = pc->buffer_size = length * tape->tape_block_size;
-       if (pc->request_transfer == tape->stage_size)
-               set_bit(PC_DMA_RECOMMENDED, &pc->flags);
-}
+       struct idetape_bh *bh = (struct idetape_bh *)rq->special;
+       unsigned int length = rq->current_nr_sectors;
 
-static void idetape_create_read_buffer_cmd(idetape_tape_t *tape, idetape_pc_t *pc, unsigned int length, struct idetape_bh *bh)
-{
-       int size = 32768;
-       struct idetape_bh *p = bh;
-
-       idetape_init_pc(pc);
-       pc->c[0] = IDETAPE_READ_BUFFER_CMD;
-       pc->c[1] = IDETAPE_RETRIEVE_FAULTY_BLOCK;
-       pc->c[7] = size >> 8;
-       pc->c[8] = size & 0xff;
-       pc->callback = &idetape_pc_callback;
+       ide_init_pc(pc);
+       put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]);
+       pc->c[1] = 1;
        pc->bh = bh;
-       atomic_set(&bh->b_count, 0);
-       pc->buffer = NULL;
-       while (p) {
-               atomic_set(&p->b_count, 0);
-               p = p->b_reqnext;
+       pc->buf = NULL;
+       pc->buf_size = length * tape->blk_size;
+       pc->req_xfer = pc->buf_size;
+       if (pc->req_xfer == tape->buffer_size)
+               pc->flags |= PC_FLAG_DMA_OK;
+
+       if (opcode == READ_6) {
+               pc->c[0] = READ_6;
+               atomic_set(&bh->b_count, 0);
+       } else if (opcode == WRITE_6) {
+               pc->c[0] = WRITE_6;
+               pc->flags |= PC_FLAG_WRITING;
+               pc->b_data = bh->b_data;
+               pc->b_count = atomic_read(&bh->b_count);
        }
-       pc->request_transfer = pc->buffer_size = size;
-}
 
-static void idetape_create_write_cmd(idetape_tape_t *tape, idetape_pc_t *pc, unsigned int length, struct idetape_bh *bh)
-{
-       idetape_init_pc(pc);
-       pc->c[0] = IDETAPE_WRITE_CMD;
-       put_unaligned(htonl(length), (unsigned int *) &pc->c[1]);
-       pc->c[1] = 1;
-       pc->callback = &idetape_rw_callback;
-       set_bit(PC_WRITING, &pc->flags);
-       pc->bh = bh;
-       pc->b_data = bh->b_data;
-       pc->b_count = atomic_read(&bh->b_count);
-       pc->buffer = NULL;
-       pc->request_transfer = pc->buffer_size = length * tape->tape_block_size;
-       if (pc->request_transfer == tape->stage_size)
-               set_bit(PC_DMA_RECOMMENDED, &pc->flags);
+       memcpy(rq->cmd, pc->c, 12);
 }
 
-/*
- * idetape_do_request is our request handling function.        
- */
 static ide_startstop_t idetape_do_request(ide_drive_t *drive,
                                          struct request *rq, sector_t block)
 {
+       ide_hwif_t *hwif = drive->hwif;
        idetape_tape_t *tape = drive->driver_data;
-       idetape_pc_t *pc = NULL;
+       struct ide_atapi_pc *pc = NULL;
        struct request *postponed_rq = tape->postponed_rq;
        u8 stat;
 
-#if IDETAPE_DEBUG_LOG
-       if (tape->debug_level >= 2)
-               printk(KERN_INFO "ide-tape: sector: %ld, "
-                       "nr_sectors: %ld, current_nr_sectors: %d\n",
-                       rq->sector, rq->nr_sectors, rq->current_nr_sectors);
-#endif /* IDETAPE_DEBUG_LOG */
+       debug_log(DBG_SENSE, "sector: %llu, nr_sectors: %lu,"
+                       " current_nr_sectors: %u\n",
+                       (unsigned long long)rq->sector, rq->nr_sectors,
+                       rq->current_nr_sectors);
 
        if (!blk_special_request(rq)) {
-               /*
-                * We do not support buffer cache originated requests.
-                */
+               /* We do not support buffer cache originated requests. */
                printk(KERN_NOTICE "ide-tape: %s: Unsupported request in "
                        "request queue (%d)\n", drive->name, rq->cmd_type);
                ide_end_request(drive, 0, 0);
                return ide_stopped;
        }
 
-       /*
-        *      Retry a failed packet command
-        */
-       if (tape->failed_pc != NULL &&
-           tape->pc->c[0] == IDETAPE_REQUEST_SENSE_CMD) {
-               return idetape_issue_packet_command(drive, tape->failed_pc);
+       /* Retry a failed packet command */
+       if (tape->failed_pc && drive->pc->c[0] == REQUEST_SENSE) {
+               pc = tape->failed_pc;
+               goto out;
        }
+
        if (postponed_rq != NULL)
                if (rq != postponed_rq) {
                        printk(KERN_ERR "ide-tape: ide-tape.c bug - "
@@ -1853,179 +825,150 @@ static ide_startstop_t idetape_do_request(ide_drive_t *drive,
         * If the tape is still busy, postpone our request and service
         * the other device meanwhile.
         */
-       stat = drive->hwif->INB(IDE_STATUS_REG);
+       stat = hwif->tp_ops->read_status(hwif);
 
-       if (!drive->dsc_overlap && !(rq->cmd[0] & REQ_IDETAPE_PC2))
-               set_bit(IDETAPE_IGNORE_DSC, &tape->flags);
+       if ((drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) == 0 &&
+           (rq->cmd[13] & REQ_IDETAPE_PC2) == 0)
+               set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags);
 
-       if (drive->post_reset == 1) {
-               set_bit(IDETAPE_IGNORE_DSC, &tape->flags);
-               drive->post_reset = 0;
+       if (drive->dev_flags & IDE_DFLAG_POST_RESET) {
+               set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags);
+               drive->dev_flags &= ~IDE_DFLAG_POST_RESET;
        }
 
-       if (tape->tape_still_time > 100 && tape->tape_still_time < 200)
-               tape->measure_insert_time = 1;
-       if (time_after(jiffies, tape->insert_time))
-               tape->insert_speed = tape->insert_size / 1024 * HZ / (jiffies - tape->insert_time);
-       calculate_speeds(drive);
-       if (!test_and_clear_bit(IDETAPE_IGNORE_DSC, &tape->flags) &&
-           (stat & SEEK_STAT) == 0) {
+       if (!test_and_clear_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags) &&
+           (stat & ATA_DSC) == 0) {
                if (postponed_rq == NULL) {
                        tape->dsc_polling_start = jiffies;
-                       tape->dsc_polling_frequency = tape->best_dsc_rw_frequency;
+                       tape->dsc_poll_freq = tape->best_dsc_rw_freq;
                        tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT;
                } else if (time_after(jiffies, tape->dsc_timeout)) {
                        printk(KERN_ERR "ide-tape: %s: DSC timeout\n",
                                tape->name);
-                       if (rq->cmd[0] & REQ_IDETAPE_PC2) {
+                       if (rq->cmd[13] & REQ_IDETAPE_PC2) {
                                idetape_media_access_finished(drive);
                                return ide_stopped;
                        } else {
                                return ide_do_reset(drive);
                        }
-               } else if (time_after(jiffies, tape->dsc_polling_start + IDETAPE_DSC_MA_THRESHOLD))
-                       tape->dsc_polling_frequency = IDETAPE_DSC_MA_SLOW;
+               } else if (time_after(jiffies,
+                                       tape->dsc_polling_start +
+                                       IDETAPE_DSC_MA_THRESHOLD))
+                       tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW;
                idetape_postpone_request(drive);
                return ide_stopped;
        }
-       if (rq->cmd[0] & REQ_IDETAPE_READ) {
-               tape->buffer_head++;
-               tape->postpone_cnt = 0;
-               pc = idetape_next_pc_storage(drive);
-               idetape_create_read_cmd(tape, pc, rq->current_nr_sectors, (struct idetape_bh *)rq->special);
-               goto out;
-       }
-       if (rq->cmd[0] & REQ_IDETAPE_WRITE) {
-               tape->buffer_head++;
-               tape->postpone_cnt = 0;
-               pc = idetape_next_pc_storage(drive);
-               idetape_create_write_cmd(tape, pc, rq->current_nr_sectors, (struct idetape_bh *)rq->special);
+       if (rq->cmd[13] & REQ_IDETAPE_READ) {
+               pc = &tape->queued_pc;
+               ide_tape_create_rw_cmd(tape, pc, rq, READ_6);
                goto out;
        }
-       if (rq->cmd[0] & REQ_IDETAPE_READ_BUFFER) {
-               tape->postpone_cnt = 0;
-               pc = idetape_next_pc_storage(drive);
-               idetape_create_read_buffer_cmd(tape, pc, rq->current_nr_sectors, (struct idetape_bh *)rq->special);
+       if (rq->cmd[13] & REQ_IDETAPE_WRITE) {
+               pc = &tape->queued_pc;
+               ide_tape_create_rw_cmd(tape, pc, rq, WRITE_6);
                goto out;
        }
-       if (rq->cmd[0] & REQ_IDETAPE_PC1) {
-               pc = (idetape_pc_t *) rq->buffer;
-               rq->cmd[0] &= ~(REQ_IDETAPE_PC1);
-               rq->cmd[0] |= REQ_IDETAPE_PC2;
+       if (rq->cmd[13] & REQ_IDETAPE_PC1) {
+               pc = (struct ide_atapi_pc *) rq->buffer;
+               rq->cmd[13] &= ~(REQ_IDETAPE_PC1);
+               rq->cmd[13] |= REQ_IDETAPE_PC2;
                goto out;
        }
-       if (rq->cmd[0] & REQ_IDETAPE_PC2) {
+       if (rq->cmd[13] & REQ_IDETAPE_PC2) {
                idetape_media_access_finished(drive);
                return ide_stopped;
        }
        BUG();
-out:
-       return idetape_issue_packet_command(drive, pc);
-}
-
-/*
- *     Pipeline related functions
- */
-static inline int idetape_pipeline_active (idetape_tape_t *tape)
-{
-       int rc1, rc2;
 
-       rc1 = test_bit(IDETAPE_PIPELINE_ACTIVE, &tape->flags);
-       rc2 = (tape->active_data_request != NULL);
-       return rc1;
+out:
+       return idetape_issue_pc(drive, pc);
 }
 
 /*
- *     idetape_kmalloc_stage uses __get_free_page to allocate a pipeline
- *     stage, along with all the necessary small buffers which together make
- *     a buffer of size tape->stage_size (or a bit more). We attempt to
- *     combine sequential pages as much as possible.
+ * The function below uses __get_free_pages to allocate a data buffer of size
+ * tape->buffer_size (or a bit more). We attempt to combine sequential pages as
+ * much as possible.
  *
- *     Returns a pointer to the new allocated stage, or NULL if we
- *     can't (or don't want to) allocate a stage.
- *
- *     Pipeline stages are optional and are used to increase performance.
- *     If we can't allocate them, we'll manage without them.
+ * It returns a pointer to the newly allocated buffer, or NULL in case of
+ * failure.
  */
-static idetape_stage_t *__idetape_kmalloc_stage (idetape_tape_t *tape, int full, int clear)
+static struct idetape_bh *ide_tape_kmalloc_buffer(idetape_tape_t *tape,
+                                                 int full, int clear)
 {
-       idetape_stage_t *stage;
-       struct idetape_bh *prev_bh, *bh;
-       int pages = tape->pages_per_stage;
+       struct idetape_bh *prev_bh, *bh, *merge_bh;
+       int pages = tape->pages_per_buffer;
+       unsigned int order, b_allocd;
        char *b_data = NULL;
 
-       if ((stage = kmalloc(sizeof (idetape_stage_t),GFP_KERNEL)) == NULL)
-               return NULL;
-       stage->next = NULL;
-
-       bh = stage->bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL);
+       merge_bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL);
+       bh = merge_bh;
        if (bh == NULL)
                goto abort;
-       bh->b_reqnext = NULL;
-       if ((bh->b_data = (char *) __get_free_page (GFP_KERNEL)) == NULL)
+
+       order = fls(pages) - 1;
+       bh->b_data = (char *) __get_free_pages(GFP_KERNEL, order);
+       if (!bh->b_data)
                goto abort;
+       b_allocd = (1 << order) * PAGE_SIZE;
+       pages &= (order-1);
+
        if (clear)
-               memset(bh->b_data, 0, PAGE_SIZE);
-       bh->b_size = PAGE_SIZE;
+               memset(bh->b_data, 0, b_allocd);
+       bh->b_reqnext = NULL;
+       bh->b_size = b_allocd;
        atomic_set(&bh->b_count, full ? bh->b_size : 0);
 
-       while (--pages) {
-               if ((b_data = (char *) __get_free_page (GFP_KERNEL)) == NULL)
+       while (pages) {
+               order = fls(pages) - 1;
+               b_data = (char *) __get_free_pages(GFP_KERNEL, order);
+               if (!b_data)
                        goto abort;
+               b_allocd = (1 << order) * PAGE_SIZE;
+
                if (clear)
-                       memset(b_data, 0, PAGE_SIZE);
-               if (bh->b_data == b_data + PAGE_SIZE) {
-                       bh->b_size += PAGE_SIZE;
-                       bh->b_data -= PAGE_SIZE;
+                       memset(b_data, 0, b_allocd);
+
+               /* newly allocated page frames below buffer header or ...*/
+               if (bh->b_data == b_data + b_allocd) {
+                       bh->b_size += b_allocd;
+                       bh->b_data -= b_allocd;
                        if (full)
-                               atomic_add(PAGE_SIZE, &bh->b_count);
+                               atomic_add(b_allocd, &bh->b_count);
                        continue;
                }
+               /* they are above the header */
                if (b_data == bh->b_data + bh->b_size) {
-                       bh->b_size += PAGE_SIZE;
+                       bh->b_size += b_allocd;
                        if (full)
-                               atomic_add(PAGE_SIZE, &bh->b_count);
+                               atomic_add(b_allocd, &bh->b_count);
                        continue;
                }
                prev_bh = bh;
-               if ((bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL)) == NULL) {
-                       free_page((unsigned long) b_data);
+               bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL);
+               if (!bh) {
+                       free_pages((unsigned long) b_data, order);
                        goto abort;
                }
                bh->b_reqnext = NULL;
                bh->b_data = b_data;
-               bh->b_size = PAGE_SIZE;
+               bh->b_size = b_allocd;
                atomic_set(&bh->b_count, full ? bh->b_size : 0);
                prev_bh->b_reqnext = bh;
+
+               pages &= (order-1);
        }
+
        bh->b_size -= tape->excess_bh_size;
        if (full)
                atomic_sub(tape->excess_bh_size, &bh->b_count);
-       return stage;
+       return merge_bh;
 abort:
-       __idetape_kfree_stage(stage);
+       ide_tape_kfree_buffer(tape);
        return NULL;
 }
 
-static idetape_stage_t *idetape_kmalloc_stage (idetape_tape_t *tape)
-{
-       idetape_stage_t *cache_stage = tape->cache_stage;
-
-#if IDETAPE_DEBUG_LOG
-       if (tape->debug_level >= 4)
-               printk(KERN_INFO "ide-tape: Reached idetape_kmalloc_stage\n");
-#endif /* IDETAPE_DEBUG_LOG */
-
-       if (tape->nr_stages >= tape->max_stages)
-               return NULL;
-       if (cache_stage != NULL) {
-               tape->cache_stage = NULL;
-               return cache_stage;
-       }
-       return __idetape_kmalloc_stage(tape, 0, 0);
-}
-
-static int idetape_copy_stage_from_user (idetape_tape_t *tape, idetape_stage_t *stage, const char __user *buf, int n)
+static int idetape_copy_stage_from_user(idetape_tape_t *tape,
+                                       const char __user *buf, int n)
 {
        struct idetape_bh *bh = tape->bh;
        int count;
@@ -2033,12 +976,15 @@ static int idetape_copy_stage_from_user (idetape_tape_t *tape, idetape_stage_t *
 
        while (n) {
                if (bh == NULL) {
-                       printk(KERN_ERR "ide-tape: bh == NULL in "
-                               "idetape_copy_stage_from_user\n");
+                       printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
+                                       __func__);
                        return 1;
                }
-               count = min((unsigned int)(bh->b_size - atomic_read(&bh->b_count)), (unsigned int)n);
-               if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf, count))
+               count = min((unsigned int)
+                               (bh->b_size - atomic_read(&bh->b_count)),
+                               (unsigned int)n);
+               if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf,
+                               count))
                        ret = 1;
                n -= count;
                atomic_add(count, &bh->b_count);
@@ -2053,7 +999,8 @@ static int idetape_copy_stage_from_user (idetape_tape_t *tape, idetape_stage_t *
        return ret;
 }
 
-static int idetape_copy_stage_to_user (idetape_tape_t *tape, char __user *buf, idetape_stage_t *stage, int n)
+static int idetape_copy_stage_to_user(idetape_tape_t *tape, char __user *buf,
+                                     int n)
 {
        struct idetape_bh *bh = tape->bh;
        int count;
@@ -2061,8 +1008,8 @@ static int idetape_copy_stage_to_user (idetape_tape_t *tape, char __user *buf, i
 
        while (n) {
                if (bh == NULL) {
-                       printk(KERN_ERR "ide-tape: bh == NULL in "
-                               "idetape_copy_stage_to_user\n");
+                       printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
+                                       __func__);
                        return 1;
                }
                count = min(tape->b_count, n);
@@ -2073,7 +1020,8 @@ static int idetape_copy_stage_to_user (idetape_tape_t *tape, char __user *buf, i
                tape->b_count -= count;
                buf += count;
                if (!tape->b_count) {
-                       tape->bh = bh = bh->b_reqnext;
+                       bh = bh->b_reqnext;
+                       tape->bh = bh;
                        if (bh) {
                                tape->b_data = bh->b_data;
                                tape->b_count = atomic_read(&bh->b_count);
@@ -2083,12 +1031,12 @@ static int idetape_copy_stage_to_user (idetape_tape_t *tape, char __user *buf, i
        return ret;
 }
 
-static void idetape_init_merge_stage (idetape_tape_t *tape)
+static void idetape_init_merge_buffer(idetape_tape_t *tape)
 {
-       struct idetape_bh *bh = tape->merge_stage->bh;
-       
-       tape->bh = bh;
-       if (tape->chrdev_direction == idetape_direction_write)
+       struct idetape_bh *bh = tape->merge_bh;
+       tape->bh = tape->merge_bh;
+
+       if (tape->chrdev_dir == IDETAPE_DIR_WRITE)
                atomic_set(&bh->b_count, 0);
        else {
                tape->b_data = bh->b_data;
@@ -2096,191 +1044,37 @@ static void idetape_init_merge_stage (idetape_tape_t *tape)
        }
 }
 
-static void idetape_switch_buffers (idetape_tape_t *tape, idetape_stage_t *stage)
-{
-       struct idetape_bh *tmp;
-
-       tmp = stage->bh;
-       stage->bh = tape->merge_stage->bh;
-       tape->merge_stage->bh = tmp;
-       idetape_init_merge_stage(tape);
-}
-
-/*
- *     idetape_add_stage_tail adds a new stage at the end of the pipeline.
- */
-static void idetape_add_stage_tail (ide_drive_t *drive,idetape_stage_t *stage)
-{
-       idetape_tape_t *tape = drive->driver_data;
-       unsigned long flags;
-       
-#if IDETAPE_DEBUG_LOG
-       if (tape->debug_level >= 4)
-               printk (KERN_INFO "ide-tape: Reached idetape_add_stage_tail\n");
-#endif /* IDETAPE_DEBUG_LOG */
-       spin_lock_irqsave(&tape->spinlock, flags);
-       stage->next = NULL;
-       if (tape->last_stage != NULL)
-               tape->last_stage->next=stage;
-       else
-               tape->first_stage = tape->next_stage=stage;
-       tape->last_stage = stage;
-       if (tape->next_stage == NULL)
-               tape->next_stage = tape->last_stage;
-       tape->nr_stages++;
-       tape->nr_pending_stages++;
-       spin_unlock_irqrestore(&tape->spinlock, flags);
-}
-
-/*
- *     idetape_wait_for_request installs a completion in a pending request
- *     and sleeps until it is serviced.
- *
- *     The caller should ensure that the request will not be serviced
- *     before we install the completion (usually by disabling interrupts).
- */
-static void idetape_wait_for_request (ide_drive_t *drive, struct request *rq)
-{
-       DECLARE_COMPLETION_ONSTACK(wait);
-       idetape_tape_t *tape = drive->driver_data;
-
-       if (rq == NULL || !blk_special_request(rq)) {
-               printk (KERN_ERR "ide-tape: bug: Trying to sleep on non-valid request\n");
-               return;
-       }
-       rq->end_io_data = &wait;
-       rq->end_io = blk_end_sync_rq;
-       spin_unlock_irq(&tape->spinlock);
-       wait_for_completion(&wait);
-       /* The stage and its struct request have been deallocated */
-       spin_lock_irq(&tape->spinlock);
-}
-
-static ide_startstop_t idetape_read_position_callback (ide_drive_t *drive)
-{
-       idetape_tape_t *tape = drive->driver_data;
-       idetape_read_position_result_t *result;
-       
-#if IDETAPE_DEBUG_LOG
-       if (tape->debug_level >= 4)
-               printk(KERN_INFO "ide-tape: Reached idetape_read_position_callback\n");
-#endif /* IDETAPE_DEBUG_LOG */
-
-       if (!tape->pc->error) {
-               result = (idetape_read_position_result_t *) tape->pc->buffer;
-#if IDETAPE_DEBUG_LOG
-               if (tape->debug_level >= 2)
-                       printk(KERN_INFO "ide-tape: BOP - %s\n",result->bop ? "Yes":"No");
-               if (tape->debug_level >= 2)
-                       printk(KERN_INFO "ide-tape: EOP - %s\n",result->eop ? "Yes":"No");
-#endif /* IDETAPE_DEBUG_LOG */
-               if (result->bpu) {
-                       printk(KERN_INFO "ide-tape: Block location is unknown to the tape\n");
-                       clear_bit(IDETAPE_ADDRESS_VALID, &tape->flags);
-                       idetape_end_request(drive, 0, 0);
-               } else {
-#if IDETAPE_DEBUG_LOG
-                       if (tape->debug_level >= 2)
-                               printk(KERN_INFO "ide-tape: Block Location - %u\n", ntohl(result->first_block));
-#endif /* IDETAPE_DEBUG_LOG */
-                       tape->partition = result->partition;
-                       tape->first_frame_position = ntohl(result->first_block);
-                       tape->last_frame_position = ntohl(result->last_block);
-                       tape->blocks_in_buffer = result->blocks_in_buffer[2];
-                       set_bit(IDETAPE_ADDRESS_VALID, &tape->flags);
-                       idetape_end_request(drive, 1, 0);
-               }
-       } else {
-               idetape_end_request(drive, 0, 0);
-       }
-       return ide_stopped;
-}
-
 /*
- *     idetape_create_write_filemark_cmd will:
- *
- *             1.      Write a filemark if write_filemark=1.
- *             2.      Flush the device buffers without writing a filemark
- *                     if write_filemark=0.
- *
+ * Write a filemark if write_filemark=1. Flush the device buffers without
+ * writing a filemark otherwise.
  */
-static void idetape_create_write_filemark_cmd (ide_drive_t *drive, idetape_pc_t *pc,int write_filemark)
+static void idetape_create_write_filemark_cmd(ide_drive_t *drive,
+               struct ide_atapi_pc *pc, int write_filemark)
 {
-       idetape_init_pc(pc);
-       pc->c[0] = IDETAPE_WRITE_FILEMARK_CMD;
+       ide_init_pc(pc);
+       pc->c[0] = WRITE_FILEMARKS;
        pc->c[4] = write_filemark;
-       set_bit(PC_WAIT_FOR_DSC, &pc->flags);
-       pc->callback = &idetape_pc_callback;
-}
-
-static void idetape_create_test_unit_ready_cmd(idetape_pc_t *pc)
-{
-       idetape_init_pc(pc);
-       pc->c[0] = IDETAPE_TEST_UNIT_READY_CMD;
-       pc->callback = &idetape_pc_callback;
-}
-
-/*
- *     idetape_queue_pc_tail is based on the following functions:
- *
- *     ide_do_drive_cmd from ide.c
- *     cdrom_queue_request and cdrom_queue_packet_command from ide-cd.c
- *
- *     We add a special packet command request to the tail of the request
- *     queue, and wait for it to be serviced.
- *
- *     This is not to be called from within the request handling part
- *     of the driver ! We allocate here data in the stack, and it is valid
- *     until the request is finished. This is not the case for the bottom
- *     part of the driver, where we are always leaving the functions to wait
- *     for an interrupt or a timer event.
- *
- *     From the bottom part of the driver, we should allocate safe memory
- *     using idetape_next_pc_storage and idetape_next_rq_storage, and add
- *     the request to the request list without waiting for it to be serviced !
- *     In that case, we usually use idetape_queue_pc_head.
- */
-static int __idetape_queue_pc_tail (ide_drive_t *drive, idetape_pc_t *pc)
-{
-       struct ide_tape_obj *tape = drive->driver_data;
-       struct request rq;
-
-       idetape_init_rq(&rq, REQ_IDETAPE_PC1);
-       rq.buffer = (char *) pc;
-       rq.rq_disk = tape->disk;
-       return ide_do_drive_cmd(drive, &rq, ide_wait);
-}
-
-static void idetape_create_load_unload_cmd (ide_drive_t *drive, idetape_pc_t *pc,int cmd)
-{
-       idetape_init_pc(pc);
-       pc->c[0] = IDETAPE_LOAD_UNLOAD_CMD;
-       pc->c[4] = cmd;
-       set_bit(PC_WAIT_FOR_DSC, &pc->flags);
-       pc->callback = &idetape_pc_callback;
+       pc->flags |= PC_FLAG_WAIT_FOR_DSC;
 }
 
 static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout)
 {
        idetape_tape_t *tape = drive->driver_data;
-       idetape_pc_t pc;
+       struct gendisk *disk = tape->disk;
        int load_attempted = 0;
 
-       /*
-        * Wait for the tape to become ready
-        */
-       set_bit(IDETAPE_MEDIUM_PRESENT, &tape->flags);
+       /* Wait for the tape to become ready */
+       set_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags);
        timeout += jiffies;
        while (time_before(jiffies, timeout)) {
-               idetape_create_test_unit_ready_cmd(&pc);
-               if (!__idetape_queue_pc_tail(drive, &pc))
+               if (ide_do_test_unit_ready(drive, disk) == 0)
                        return 0;
                if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2)
-                   || (tape->asc == 0x3A)) {   /* no media */
+                   || (tape->asc == 0x3A)) {
+                       /* no media */
                        if (load_attempted)
                                return -ENOMEDIUM;
-                       idetape_create_load_unload_cmd(drive, &pc, IDETAPE_LU_LOAD_MASK);
-                       __idetape_queue_pc_tail(drive, &pc);
+                       ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK);
                        load_attempted = 1;
                /* not about to be ready */
                } else if (!(tape->sense_key == 2 && tape->asc == 4 &&
@@ -2291,382 +1085,219 @@ static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout)
        return -EIO;
 }
 
-static int idetape_queue_pc_tail (ide_drive_t *drive,idetape_pc_t *pc)
-{
-       return __idetape_queue_pc_tail(drive, pc);
-}
-
-static int idetape_flush_tape_buffers (ide_drive_t *drive)
+static int idetape_flush_tape_buffers(ide_drive_t *drive)
 {
-       idetape_pc_t pc;
+       struct ide_tape_obj *tape = drive->driver_data;
+       struct ide_atapi_pc pc;
        int rc;
 
        idetape_create_write_filemark_cmd(drive, &pc, 0);
-       if ((rc = idetape_queue_pc_tail(drive, &pc)))
+       rc = ide_queue_pc_tail(drive, tape->disk, &pc);
+       if (rc)
                return rc;
        idetape_wait_ready(drive, 60 * 5 * HZ);
        return 0;
 }
 
-static void idetape_create_read_position_cmd (idetape_pc_t *pc)
+static void idetape_create_read_position_cmd(struct ide_atapi_pc *pc)
 {
-       idetape_init_pc(pc);
-       pc->c[0] = IDETAPE_READ_POSITION_CMD;
-       pc->request_transfer = 20;
-       pc->callback = &idetape_read_position_callback;
+       ide_init_pc(pc);
+       pc->c[0] = READ_POSITION;
+       pc->req_xfer = 20;
 }
 
-static int idetape_read_position (ide_drive_t *drive)
+static int idetape_read_position(ide_drive_t *drive)
 {
        idetape_tape_t *tape = drive->driver_data;
-       idetape_pc_t pc;
+       struct ide_atapi_pc pc;
        int position;
 
-#if IDETAPE_DEBUG_LOG
-        if (tape->debug_level >= 4)
-               printk(KERN_INFO "ide-tape: Reached idetape_read_position\n");
-#endif /* IDETAPE_DEBUG_LOG */
+       debug_log(DBG_PROCS, "Enter %s\n", __func__);
 
        idetape_create_read_position_cmd(&pc);
-       if (idetape_queue_pc_tail(drive, &pc))
+       if (ide_queue_pc_tail(drive, tape->disk, &pc))
                return -1;
-       position = tape->first_frame_position;
+       position = tape->first_frame;
        return position;
 }
 
-static void idetape_create_locate_cmd (ide_drive_t *drive, idetape_pc_t *pc, unsigned int block, u8 partition, int skip)
+static void idetape_create_locate_cmd(ide_drive_t *drive,
+               struct ide_atapi_pc *pc,
+               unsigned int block, u8 partition, int skip)
 {
-       idetape_init_pc(pc);
-       pc->c[0] = IDETAPE_LOCATE_CMD;
+       ide_init_pc(pc);
+       pc->c[0] = POSITION_TO_ELEMENT;
        pc->c[1] = 2;
-       put_unaligned(htonl(block), (unsigned int *) &pc->c[3]);
+       put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]);
        pc->c[8] = partition;
-       set_bit(PC_WAIT_FOR_DSC, &pc->flags);
-       pc->callback = &idetape_pc_callback;
+       pc->flags |= PC_FLAG_WAIT_FOR_DSC;
 }
 
-static int idetape_create_prevent_cmd (ide_drive_t *drive, idetape_pc_t *pc, int prevent)
+static void __ide_tape_discard_merge_buffer(ide_drive_t *drive)
 {
        idetape_tape_t *tape = drive->driver_data;
 
-       /* device supports locking according to capabilities page */
-       if (!(tape->caps[6] & 0x01))
-               return 0;
-
-       idetape_init_pc(pc);
-       pc->c[0] = IDETAPE_PREVENT_CMD;
-       pc->c[4] = prevent;
-       pc->callback = &idetape_pc_callback;
-       return 1;
-}
-
-static int __idetape_discard_read_pipeline (ide_drive_t *drive)
-{
-       idetape_tape_t *tape = drive->driver_data;
-       unsigned long flags;
-       int cnt;
-
-       if (tape->chrdev_direction != idetape_direction_read)
-               return 0;
+       if (tape->chrdev_dir != IDETAPE_DIR_READ)
+               return;
 
-       /* Remove merge stage. */
-       cnt = tape->merge_stage_size / tape->tape_block_size;
-       if (test_and_clear_bit(IDETAPE_FILEMARK, &tape->flags))
-               ++cnt;          /* Filemarks count as 1 sector */
-       tape->merge_stage_size = 0;
-       if (tape->merge_stage != NULL) {
-               __idetape_kfree_stage(tape->merge_stage);
-               tape->merge_stage = NULL;
+       clear_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags);
+       tape->merge_bh_size = 0;
+       if (tape->merge_bh != NULL) {
+               ide_tape_kfree_buffer(tape);
+               tape->merge_bh = NULL;
        }
 
-       /* Clear pipeline flags. */
-       clear_bit(IDETAPE_PIPELINE_ERROR, &tape->flags);
-       tape->chrdev_direction = idetape_direction_none;
-
-       /* Remove pipeline stages. */
-       if (tape->first_stage == NULL)
-               return 0;
-
-       spin_lock_irqsave(&tape->spinlock, flags);
-       tape->next_stage = NULL;
-       if (idetape_pipeline_active(tape))
-               idetape_wait_for_request(drive, tape->active_data_request);
-       spin_unlock_irqrestore(&tape->spinlock, flags);
-
-       while (tape->first_stage != NULL) {
-               struct request *rq_ptr = &tape->first_stage->rq;
-
-               cnt += rq_ptr->nr_sectors - rq_ptr->current_nr_sectors; 
-               if (rq_ptr->errors == IDETAPE_ERROR_FILEMARK)
-                       ++cnt;
-               idetape_remove_stage_head(drive);
-       }
-       tape->nr_pending_stages = 0;
-       tape->max_stages = tape->min_pipeline;
-       return cnt;
+       tape->chrdev_dir = IDETAPE_DIR_NONE;
 }
 
 /*
- *     idetape_position_tape positions the tape to the requested block
- *     using the LOCATE packet command. A READ POSITION command is then
- *     issued to check where we are positioned.
- *
- *     Like all higher level operations, we queue the commands at the tail
- *     of the request queue and wait for their completion.
- *     
+ * Position the tape to the requested block using the LOCATE packet command.
+ * A READ POSITION command is then issued to check where we are positioned. Like
+ * all higher level operations, we queue the commands at the tail of the request
+ * queue and wait for their completion.
  */
-static int idetape_position_tape (ide_drive_t *drive, unsigned int block, u8 partition, int skip)
+static int idetape_position_tape(ide_drive_t *drive, unsigned int block,
+               u8 partition, int skip)
 {
        idetape_tape_t *tape = drive->driver_data;
+       struct gendisk *disk = tape->disk;
        int retval;
-       idetape_pc_t pc;
+       struct ide_atapi_pc pc;
 
-       if (tape->chrdev_direction == idetape_direction_read)
-               __idetape_discard_read_pipeline(drive);
+       if (tape->chrdev_dir == IDETAPE_DIR_READ)
+               __ide_tape_discard_merge_buffer(drive);
        idetape_wait_ready(drive, 60 * 5 * HZ);
        idetape_create_locate_cmd(drive, &pc, block, partition, skip);
-       retval = idetape_queue_pc_tail(drive, &pc);
+       retval = ide_queue_pc_tail(drive, disk, &pc);
        if (retval)
                return (retval);
 
        idetape_create_read_position_cmd(&pc);
-       return (idetape_queue_pc_tail(drive, &pc));
+       return ide_queue_pc_tail(drive, disk, &pc);
 }
 
-static void idetape_discard_read_pipeline (ide_drive_t *drive, int restore_position)
+static void ide_tape_discard_merge_buffer(ide_drive_t *drive,
+                                         int restore_position)
 {
        idetape_tape_t *tape = drive->driver_data;
-       int cnt;
        int seek, position;
 
-       cnt = __idetape_discard_read_pipeline(drive);
+       __ide_tape_discard_merge_buffer(drive);
        if (restore_position) {
                position = idetape_read_position(drive);
-               seek = position > cnt ? position - cnt : 0;
+               seek = position > 0 ? position : 0;
                if (idetape_position_tape(drive, seek, 0, 0)) {
-                       printk(KERN_INFO "ide-tape: %s: position_tape failed in discard_pipeline()\n", tape->name);
+                       printk(KERN_INFO "ide-tape: %s: position_tape failed in"
+                                        " %s\n", tape->name, __func__);
                        return;
                }
        }
 }
 
 /*
- * idetape_queue_rw_tail generates a read/write request for the block
- * device interface and wait for it to be serviced.
+ * Generate a read/write request for the block device interface and wait for it
+ * to be serviced.
  */
-static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks, struct idetape_bh *bh)
+static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks,
+                                struct idetape_bh *bh)
 {
        idetape_tape_t *tape = drive->driver_data;
-       struct request rq;
+       struct request *rq;
+       int ret, errors;
 
-#if IDETAPE_DEBUG_LOG
-       if (tape->debug_level >= 2)
-               printk(KERN_INFO "ide-tape: idetape_queue_rw_tail: cmd=%d\n",cmd);
-#endif /* IDETAPE_DEBUG_LOG */
-       if (idetape_pipeline_active(tape)) {
-               printk(KERN_ERR "ide-tape: bug: the pipeline is active in idetape_queue_rw_tail\n");
-               return (0);
-       }
+       debug_log(DBG_SENSE, "%s: cmd=%d\n", __func__, cmd);
+
+       rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
+       rq->cmd_type = REQ_TYPE_SPECIAL;
+       rq->cmd[13] = cmd;
+       rq->rq_disk = tape->disk;
+       rq->special = (void *)bh;
+       rq->sector = tape->first_frame;
+       rq->nr_sectors = blocks;
+       rq->current_nr_sectors = blocks;
+       blk_execute_rq(drive->queue, tape->disk, rq, 0);
 
-       idetape_init_rq(&rq, cmd);
-       rq.rq_disk = tape->disk;
-       rq.special = (void *)bh;
-       rq.sector = tape->first_frame_position;
-       rq.nr_sectors = rq.current_nr_sectors = blocks;
-       (void) ide_do_drive_cmd(drive, &rq, ide_wait);
+       errors = rq->errors;
+       ret = tape->blk_size * (blocks - rq->current_nr_sectors);
+       blk_put_request(rq);
 
        if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0)
                return 0;
 
-       if (tape->merge_stage)
-               idetape_init_merge_stage(tape);
-       if (rq.errors == IDETAPE_ERROR_GENERAL)
-               return -EIO;
-       return (tape->tape_block_size * (blocks-rq.current_nr_sectors));
-}
-
-/*
- *     idetape_insert_pipeline_into_queue is used to start servicing the
- *     pipeline stages, starting from tape->next_stage.
- */
-static void idetape_insert_pipeline_into_queue (ide_drive_t *drive)
-{
-       idetape_tape_t *tape = drive->driver_data;
-
-       if (tape->next_stage == NULL)
-               return;
-       if (!idetape_pipeline_active(tape)) {
-               set_bit(IDETAPE_PIPELINE_ACTIVE, &tape->flags);
-               idetape_active_next_stage(drive);
-               (void) ide_do_drive_cmd(drive, tape->active_data_request, ide_end);
-       }
+       if (tape->merge_bh)
+               idetape_init_merge_buffer(tape);
+       if (errors == IDETAPE_ERROR_GENERAL)
+               return -EIO;
+       return ret;
 }
 
-static void idetape_create_inquiry_cmd (idetape_pc_t *pc)
+static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc)
 {
-       idetape_init_pc(pc);
-       pc->c[0] = IDETAPE_INQUIRY_CMD;
-       pc->c[4] = pc->request_transfer = 254;
-       pc->callback = &idetape_pc_callback;
+       ide_init_pc(pc);
+       pc->c[0] = INQUIRY;
+       pc->c[4] = 254;
+       pc->req_xfer = 254;
 }
 
-static void idetape_create_rewind_cmd (ide_drive_t *drive, idetape_pc_t *pc)
+static void idetape_create_rewind_cmd(ide_drive_t *drive,
+               struct ide_atapi_pc *pc)
 {
-       idetape_init_pc(pc);
-       pc->c[0] = IDETAPE_REWIND_CMD;
-       set_bit(PC_WAIT_FOR_DSC, &pc->flags);
-       pc->callback = &idetape_pc_callback;
+       ide_init_pc(pc);
+       pc->c[0] = REZERO_UNIT;
+       pc->flags |= PC_FLAG_WAIT_FOR_DSC;
 }
 
-static void idetape_create_erase_cmd (idetape_pc_t *pc)
+static void idetape_create_erase_cmd(struct ide_atapi_pc *pc)
 {
-       idetape_init_pc(pc);
-       pc->c[0] = IDETAPE_ERASE_CMD;
+       ide_init_pc(pc);
+       pc->c[0] = ERASE;
        pc->c[1] = 1;
-       set_bit(PC_WAIT_FOR_DSC, &pc->flags);
-       pc->callback = &idetape_pc_callback;
+       pc->flags |= PC_FLAG_WAIT_FOR_DSC;
 }
 
-static void idetape_create_space_cmd (idetape_pc_t *pc,int count, u8 cmd)
+static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd)
 {
-       idetape_init_pc(pc);
-       pc->c[0] = IDETAPE_SPACE_CMD;
-       put_unaligned(htonl(count), (unsigned int *) &pc->c[1]);
+       ide_init_pc(pc);
+       pc->c[0] = SPACE;
+       put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]);
        pc->c[1] = cmd;
-       set_bit(PC_WAIT_FOR_DSC, &pc->flags);
-       pc->callback = &idetape_pc_callback;
-}
-
-static void idetape_wait_first_stage (ide_drive_t *drive)
-{
-       idetape_tape_t *tape = drive->driver_data;
-       unsigned long flags;
-
-       if (tape->first_stage == NULL)
-               return;
-       spin_lock_irqsave(&tape->spinlock, flags);
-       if (tape->active_stage == tape->first_stage)
-               idetape_wait_for_request(drive, tape->active_data_request);
-       spin_unlock_irqrestore(&tape->spinlock, flags);
+       pc->flags |= PC_FLAG_WAIT_FOR_DSC;
 }
 
-/*
- *     idetape_add_chrdev_write_request tries to add a character device
- *     originated write request to our pipeline. In case we don't succeed,
- *     we revert to non-pipelined operation mode for this request.
- *
- *     1.      Try to allocate a new pipeline stage.
- *     2.      If we can't, wait for more and more requests to be serviced
- *             and try again each time.
- *     3.      If we still can't allocate a stage, fallback to
- *             non-pipelined operation mode for this request.
- */
-static int idetape_add_chrdev_write_request (ide_drive_t *drive, int blocks)
+/* Queue up a character device originated write request. */
+static int idetape_add_chrdev_write_request(ide_drive_t *drive, int blocks)
 {
        idetape_tape_t *tape = drive->driver_data;
-       idetape_stage_t *new_stage;
-       unsigned long flags;
-       struct request *rq;
 
-#if IDETAPE_DEBUG_LOG
-       if (tape->debug_level >= 3)
-               printk(KERN_INFO "ide-tape: Reached idetape_add_chrdev_write_request\n");
-#endif /* IDETAPE_DEBUG_LOG */
-
-       /*
-        *      Attempt to allocate a new stage.
-        *      Pay special attention to possible race conditions.
-        */
-       while ((new_stage = idetape_kmalloc_stage(tape)) == NULL) {
-               spin_lock_irqsave(&tape->spinlock, flags);
-               if (idetape_pipeline_active(tape)) {
-                       idetape_wait_for_request(drive, tape->active_data_request);
-                       spin_unlock_irqrestore(&tape->spinlock, flags);
-               } else {
-                       spin_unlock_irqrestore(&tape->spinlock, flags);
-                       idetape_insert_pipeline_into_queue(drive);
-                       if (idetape_pipeline_active(tape))
-                               continue;
-                       /*
-                        *      Linux is short on memory. Fallback to
-                        *      non-pipelined operation mode for this request.
-                        */
-                       return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, tape->merge_stage->bh);
-               }
-       }
-       rq = &new_stage->rq;
-       idetape_init_rq(rq, REQ_IDETAPE_WRITE);
-       /* Doesn't actually matter - We always assume sequential access */
-       rq->sector = tape->first_frame_position;
-       rq->nr_sectors = rq->current_nr_sectors = blocks;
-
-       idetape_switch_buffers(tape, new_stage);
-       idetape_add_stage_tail(drive, new_stage);
-       tape->pipeline_head++;
-       calculate_speeds(drive);
-
-       /*
-        *      Estimate whether the tape has stopped writing by checking
-        *      if our write pipeline is currently empty. If we are not
-        *      writing anymore, wait for the pipeline to be full enough
-        *      (90%) before starting to service requests, so that we will
-        *      be able to keep up with the higher speeds of the tape.
-        */
-       if (!idetape_pipeline_active(tape)) {
-               if (tape->nr_stages >= tape->max_stages * 9 / 10 ||
-                   tape->nr_stages >= tape->max_stages - tape->uncontrolled_pipeline_head_speed * 3 * 1024 / tape->tape_block_size) {
-                       tape->measure_insert_time = 1;
-                       tape->insert_time = jiffies;
-                       tape->insert_size = 0;
-                       tape->insert_speed = 0;
-                       idetape_insert_pipeline_into_queue(drive);
-               }
-       }
-       if (test_and_clear_bit(IDETAPE_PIPELINE_ERROR, &tape->flags))
-               /* Return a deferred error */
-               return -EIO;
-       return blocks;
-}
-
-/*
- *     idetape_wait_for_pipeline will wait until all pending pipeline
- *     requests are serviced. Typically called on device close.
- */
-static void idetape_wait_for_pipeline (ide_drive_t *drive)
-{
-       idetape_tape_t *tape = drive->driver_data;
-       unsigned long flags;
+       debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
 
-       while (tape->next_stage || idetape_pipeline_active(tape)) {
-               idetape_insert_pipeline_into_queue(drive);
-               spin_lock_irqsave(&tape->spinlock, flags);
-               if (idetape_pipeline_active(tape))
-                       idetape_wait_for_request(drive, tape->active_data_request);
-               spin_unlock_irqrestore(&tape->spinlock, flags);
-       }
+       return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE,
+                                    blocks, tape->merge_bh);
 }
 
-static void idetape_empty_write_pipeline (ide_drive_t *drive)
+static void ide_tape_flush_merge_buffer(ide_drive_t *drive)
 {
        idetape_tape_t *tape = drive->driver_data;
        int blocks, min;
        struct idetape_bh *bh;
 
-       if (tape->chrdev_direction != idetape_direction_write) {
-               printk(KERN_ERR "ide-tape: bug: Trying to empty write pipeline, but we are not writing.\n");
+       if (tape->chrdev_dir != IDETAPE_DIR_WRITE) {
+               printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer"
+                               " but we are not writing.\n");
                return;
        }
-       if (tape->merge_stage_size > tape->stage_size) {
+       if (tape->merge_bh_size > tape->buffer_size) {
                printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n");
-               tape->merge_stage_size = tape->stage_size;
+               tape->merge_bh_size = tape->buffer_size;
        }
-       if (tape->merge_stage_size) {
-               blocks = tape->merge_stage_size / tape->tape_block_size;
-               if (tape->merge_stage_size % tape->tape_block_size) {
+       if (tape->merge_bh_size) {
+               blocks = tape->merge_bh_size / tape->blk_size;
+               if (tape->merge_bh_size % tape->blk_size) {
                        unsigned int i;
 
                        blocks++;
-                       i = tape->tape_block_size - tape->merge_stage_size % tape->tape_block_size;
+                       i = tape->blk_size - tape->merge_bh_size %
+                               tape->blk_size;
                        bh = tape->bh->b_reqnext;
                        while (bh) {
                                atomic_set(&bh->b_count, 0);
@@ -2675,307 +1306,179 @@ static void idetape_empty_write_pipeline (ide_drive_t *drive)
                        bh = tape->bh;
                        while (i) {
                                if (bh == NULL) {
-
-                                       printk(KERN_INFO "ide-tape: bug, bh NULL\n");
+                                       printk(KERN_INFO "ide-tape: bug,"
+                                                        " bh NULL\n");
                                        break;
                                }
-                               min = min(i, (unsigned int)(bh->b_size - atomic_read(&bh->b_count)));
-                               memset(bh->b_data + atomic_read(&bh->b_count), 0, min);
+                               min = min(i, (unsigned int)(bh->b_size -
+                                               atomic_read(&bh->b_count)));
+                               memset(bh->b_data + atomic_read(&bh->b_count),
+                                               0, min);
                                atomic_add(min, &bh->b_count);
                                i -= min;
                                bh = bh->b_reqnext;
                        }
                }
                (void) idetape_add_chrdev_write_request(drive, blocks);
-               tape->merge_stage_size = 0;
+               tape->merge_bh_size = 0;
        }
-       idetape_wait_for_pipeline(drive);
-       if (tape->merge_stage != NULL) {
-               __idetape_kfree_stage(tape->merge_stage);
-               tape->merge_stage = NULL;
-       }
-       clear_bit(IDETAPE_PIPELINE_ERROR, &tape->flags);
-       tape->chrdev_direction = idetape_direction_none;
-
-       /*
-        *      On the next backup, perform the feedback loop again.
-        *      (I don't want to keep sense information between backups,
-        *       as some systems are constantly on, and the system load
-        *       can be totally different on the next backup).
-        */
-       tape->max_stages = tape->min_pipeline;
-       if (tape->first_stage != NULL ||
-           tape->next_stage != NULL ||
-           tape->last_stage != NULL ||
-           tape->nr_stages != 0) {
-               printk(KERN_ERR "ide-tape: ide-tape pipeline bug, "
-                       "first_stage %p, next_stage %p, "
-                       "last_stage %p, nr_stages %d\n",
-                       tape->first_stage, tape->next_stage,
-                       tape->last_stage, tape->nr_stages);
+       if (tape->merge_bh != NULL) {
+               ide_tape_kfree_buffer(tape);
+               tape->merge_bh = NULL;
        }
+       tape->chrdev_dir = IDETAPE_DIR_NONE;
 }
 
-static void idetape_restart_speed_control (ide_drive_t *drive)
-{
-       idetape_tape_t *tape = drive->driver_data;
-
-       tape->restart_speed_control_req = 0;
-       tape->pipeline_head = 0;
-       tape->controlled_last_pipeline_head = tape->uncontrolled_last_pipeline_head = 0;
-       tape->controlled_previous_pipeline_head = tape->uncontrolled_previous_pipeline_head = 0;
-       tape->pipeline_head_speed = tape->controlled_pipeline_head_speed = 5000;
-       tape->uncontrolled_pipeline_head_speed = 0;
-       tape->controlled_pipeline_head_time = tape->uncontrolled_pipeline_head_time = jiffies;
-       tape->controlled_previous_head_time = tape->uncontrolled_previous_head_time = jiffies;
-}
-
-static int idetape_initiate_read (ide_drive_t *drive, int max_stages)
+static int idetape_init_read(ide_drive_t *drive)
 {
        idetape_tape_t *tape = drive->driver_data;
-       idetape_stage_t *new_stage;
-       struct request rq;
        int bytes_read;
-       u16 blocks = *(u16 *)&tape->caps[12];
 
        /* Initialize read operation */
-       if (tape->chrdev_direction != idetape_direction_read) {
-               if (tape->chrdev_direction == idetape_direction_write) {
-                       idetape_empty_write_pipeline(drive);
+       if (tape->chrdev_dir != IDETAPE_DIR_READ) {
+               if (tape->chrdev_dir == IDETAPE_DIR_WRITE) {
+                       ide_tape_flush_merge_buffer(drive);
                        idetape_flush_tape_buffers(drive);
                }
-               if (tape->merge_stage || tape->merge_stage_size) {
-                       printk (KERN_ERR "ide-tape: merge_stage_size should be 0 now\n");
-                       tape->merge_stage_size = 0;
+               if (tape->merge_bh || tape->merge_bh_size) {
+                       printk(KERN_ERR "ide-tape: merge_bh_size should be"
+                                        " 0 now\n");
+                       tape->merge_bh_size = 0;
                }
-               if ((tape->merge_stage = __idetape_kmalloc_stage(tape, 0, 0)) == NULL)
+               tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0);
+               if (!tape->merge_bh)
                        return -ENOMEM;
-               tape->chrdev_direction = idetape_direction_read;
+               tape->chrdev_dir = IDETAPE_DIR_READ;
 
                /*
-                *      Issue a read 0 command to ensure that DSC handshake
-                *      is switched from completion mode to buffer available
-                *      mode.
-                *      No point in issuing this if DSC overlap isn't supported,
-                *      some drives (Seagate STT3401A) will return an error.
+                * Issue a read 0 command to ensure that DSC handshake is
+                * switched from completion mode to buffer available mode.
+                * No point in issuing this if DSC overlap isn't supported, some
+                * drives (Seagate STT3401A) will return an error.
                 */
-               if (drive->dsc_overlap) {
-                       bytes_read = idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, 0, tape->merge_stage->bh);
+               if (drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) {
+                       bytes_read = idetape_queue_rw_tail(drive,
+                                                       REQ_IDETAPE_READ, 0,
+                                                       tape->merge_bh);
                        if (bytes_read < 0) {
-                               __idetape_kfree_stage(tape->merge_stage);
-                               tape->merge_stage = NULL;
-                               tape->chrdev_direction = idetape_direction_none;
+                               ide_tape_kfree_buffer(tape);
+                               tape->merge_bh = NULL;
+                               tape->chrdev_dir = IDETAPE_DIR_NONE;
                                return bytes_read;
                        }
                }
        }
-       if (tape->restart_speed_control_req)
-               idetape_restart_speed_control(drive);
-       idetape_init_rq(&rq, REQ_IDETAPE_READ);
-       rq.sector = tape->first_frame_position;
-       rq.nr_sectors = rq.current_nr_sectors = blocks;
-       if (!test_bit(IDETAPE_PIPELINE_ERROR, &tape->flags) &&
-           tape->nr_stages < max_stages) {
-               new_stage = idetape_kmalloc_stage(tape);
-               while (new_stage != NULL) {
-                       new_stage->rq = rq;
-                       idetape_add_stage_tail(drive, new_stage);
-                       if (tape->nr_stages >= max_stages)
-                               break;
-                       new_stage = idetape_kmalloc_stage(tape);
-               }
-       }
-       if (!idetape_pipeline_active(tape)) {
-               if (tape->nr_pending_stages >= 3 * max_stages / 4) {
-                       tape->measure_insert_time = 1;
-                       tape->insert_time = jiffies;
-                       tape->insert_size = 0;
-                       tape->insert_speed = 0;
-                       idetape_insert_pipeline_into_queue(drive);
-               }
-       }
+
        return 0;
 }
 
-/*
- *     idetape_add_chrdev_read_request is called from idetape_chrdev_read
- *     to service a character device read request and add read-ahead
- *     requests to our pipeline.
- */
-static int idetape_add_chrdev_read_request (ide_drive_t *drive,int blocks)
+/* called from idetape_chrdev_read() to service a chrdev read request. */
+static int idetape_add_chrdev_read_request(ide_drive_t *drive, int blocks)
 {
        idetape_tape_t *tape = drive->driver_data;
-       unsigned long flags;
-       struct request *rq_ptr;
-       int bytes_read;
 
-#if IDETAPE_DEBUG_LOG
-       if (tape->debug_level >= 4)
-               printk(KERN_INFO "ide-tape: Reached idetape_add_chrdev_read_request, %d blocks\n", blocks);
-#endif /* IDETAPE_DEBUG_LOG */
+       debug_log(DBG_PROCS, "Enter %s, %d blocks\n", __func__, blocks);
 
-       /*
-        * If we are at a filemark, return a read length of 0
-        */
-       if (test_bit(IDETAPE_FILEMARK, &tape->flags))
+       /* If we are at a filemark, return a read length of 0 */
+       if (test_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags))
                return 0;
 
-       /*
-        * Wait for the next block to be available at the head
-        * of the pipeline
-        */
-       idetape_initiate_read(drive, tape->max_stages);
-       if (tape->first_stage == NULL) {
-               if (test_bit(IDETAPE_PIPELINE_ERROR, &tape->flags))
-                       return 0;
-               return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks, tape->merge_stage->bh);
-       }
-       idetape_wait_first_stage(drive);
-       rq_ptr = &tape->first_stage->rq;
-       bytes_read = tape->tape_block_size * (rq_ptr->nr_sectors - rq_ptr->current_nr_sectors);
-       rq_ptr->nr_sectors = rq_ptr->current_nr_sectors = 0;
-
+       idetape_init_read(drive);
 
-       if (rq_ptr->errors == IDETAPE_ERROR_EOD)
-               return 0;
-       else {
-               idetape_switch_buffers(tape, tape->first_stage);
-               if (rq_ptr->errors == IDETAPE_ERROR_FILEMARK)
-                       set_bit(IDETAPE_FILEMARK, &tape->flags);
-               spin_lock_irqsave(&tape->spinlock, flags);
-               idetape_remove_stage_head(drive);
-               spin_unlock_irqrestore(&tape->spinlock, flags);
-               tape->pipeline_head++;
-               calculate_speeds(drive);
-       }
-       if (bytes_read > blocks * tape->tape_block_size) {
-               printk(KERN_ERR "ide-tape: bug: trying to return more bytes than requested\n");
-               bytes_read = blocks * tape->tape_block_size;
-       }
-       return (bytes_read);
+       return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks,
+                                    tape->merge_bh);
 }
 
-static void idetape_pad_zeros (ide_drive_t *drive, int bcount)
+static void idetape_pad_zeros(ide_drive_t *drive, int bcount)
 {
        idetape_tape_t *tape = drive->driver_data;
        struct idetape_bh *bh;
        int blocks;
-       
+
        while (bcount) {
                unsigned int count;
 
-               bh = tape->merge_stage->bh;
-               count = min(tape->stage_size, bcount);
+               bh = tape->merge_bh;
+               count = min(tape->buffer_size, bcount);
                bcount -= count;
-               blocks = count / tape->tape_block_size;
+               blocks = count / tape->blk_size;
                while (count) {
-                       atomic_set(&bh->b_count, min(count, (unsigned int)bh->b_size));
+                       atomic_set(&bh->b_count,
+                                  min(count, (unsigned int)bh->b_size));
                        memset(bh->b_data, 0, atomic_read(&bh->b_count));
                        count -= atomic_read(&bh->b_count);
                        bh = bh->b_reqnext;
                }
-               idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, tape->merge_stage->bh);
-       }
-}
-
-static int idetape_pipeline_size (ide_drive_t *drive)
-{
-       idetape_tape_t *tape = drive->driver_data;
-       idetape_stage_t *stage;
-       struct request *rq;
-       int size = 0;
-
-       idetape_wait_for_pipeline(drive);
-       stage = tape->first_stage;
-       while (stage != NULL) {
-               rq = &stage->rq;
-               size += tape->tape_block_size * (rq->nr_sectors-rq->current_nr_sectors);
-               if (rq->errors == IDETAPE_ERROR_FILEMARK)
-                       size += tape->tape_block_size;
-               stage = stage->next;
+               idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks,
+                                     tape->merge_bh);
        }
-       size += tape->merge_stage_size;
-       return size;
 }
 
 /*
- *     Rewinds the tape to the Beginning Of the current Partition (BOP).
- *
- *     We currently support only one partition.
- */ 
-static int idetape_rewind_tape (ide_drive_t *drive)
+ * Rewinds the tape to the Beginning Of the current Partition (BOP). We
+ * currently support only one partition.
+ */
+static int idetape_rewind_tape(ide_drive_t *drive)
 {
+       struct ide_tape_obj *tape = drive->driver_data;
+       struct gendisk *disk = tape->disk;
        int retval;
-       idetape_pc_t pc;
-#if IDETAPE_DEBUG_LOG
-       idetape_tape_t *tape = drive->driver_data;
-       if (tape->debug_level >= 2)
-               printk(KERN_INFO "ide-tape: Reached idetape_rewind_tape\n");
-#endif /* IDETAPE_DEBUG_LOG */ 
-       
+       struct ide_atapi_pc pc;
+
+       debug_log(DBG_SENSE, "Enter %s\n", __func__);
+
        idetape_create_rewind_cmd(drive, &pc);
-       retval = idetape_queue_pc_tail(drive, &pc);
+       retval = ide_queue_pc_tail(drive, disk, &pc);
        if (retval)
                return retval;
 
        idetape_create_read_position_cmd(&pc);
-       retval = idetape_queue_pc_tail(drive, &pc);
+       retval = ide_queue_pc_tail(drive, disk, &pc);
        if (retval)
                return retval;
        return 0;
 }
 
-/*
- *     Our special ide-tape ioctl's.
- *
- *     Currently there aren't any ioctl's.
- *     mtio.h compatible commands should be issued to the character device
- *     interface.
- */
-static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd, unsigned long arg)
+/* mtio.h compatible commands should be issued to the chrdev interface. */
+static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd,
+                               unsigned long arg)
 {
        idetape_tape_t *tape = drive->driver_data;
-       idetape_config_t config;
        void __user *argp = (void __user *)arg;
 
-#if IDETAPE_DEBUG_LOG  
-       if (tape->debug_level >= 4)
-               printk(KERN_INFO "ide-tape: Reached idetape_blkdev_ioctl\n");
-#endif /* IDETAPE_DEBUG_LOG */
+       struct idetape_config {
+               int dsc_rw_frequency;
+               int dsc_media_access_frequency;
+               int nr_stages;
+       } config;
+
+       debug_log(DBG_PROCS, "Enter %s\n", __func__);
+
        switch (cmd) {
-               case 0x0340:
-                       if (copy_from_user(&config, argp, sizeof (idetape_config_t)))
-                               return -EFAULT;
-                       tape->best_dsc_rw_frequency = config.dsc_rw_frequency;
-                       tape->max_stages = config.nr_stages;
-                       break;
-               case 0x0350:
-                       config.dsc_rw_frequency = (int) tape->best_dsc_rw_frequency;
-                       config.nr_stages = tape->max_stages; 
-                       if (copy_to_user(argp, &config, sizeof (idetape_config_t)))
-                               return -EFAULT;
-                       break;
-               default:
-                       return -EIO;
+       case 0x0340:
+               if (copy_from_user(&config, argp, sizeof(config)))
+                       return -EFAULT;
+               tape->best_dsc_rw_freq = config.dsc_rw_frequency;
+               break;
+       case 0x0350:
+               config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq;
+               config.nr_stages = 1;
+               if (copy_to_user(argp, &config, sizeof(config)))
+                       return -EFAULT;
+               break;
+       default:
+               return -EIO;
        }
        return 0;
 }
 
-/*
- *     idetape_space_over_filemarks is now a bit more complicated than just
- *     passing the command to the tape since we may have crossed some
- *     filemarks during our pipelined read-ahead mode.
- *
- *     As a minor side effect, the pipeline enables us to support MTFSFM when
- *     the filemark is in our internal pipeline even if the tape doesn't
- *     support spacing over filemarks in the reverse direction.
- */
-static int idetape_space_over_filemarks (ide_drive_t *drive,short mt_op,int mt_count)
+static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op,
+                                       int mt_count)
 {
        idetape_tape_t *tape = drive->driver_data;
-       idetape_pc_t pc;
-       unsigned long flags;
-       int retval,count=0;
+       struct gendisk *disk = tape->disk;
+       struct ide_atapi_pc pc;
+       int retval, count = 0;
        int sprev = !!(tape->caps[4] & 0x20);
 
        if (mt_count == 0)
@@ -2983,125 +1486,90 @@ static int idetape_space_over_filemarks (ide_drive_t *drive,short mt_op,int mt_c
        if (MTBSF == mt_op || MTBSFM == mt_op) {
                if (!sprev)
                        return -EIO;
-               mt_count = - mt_count;
+               mt_count = -mt_count;
        }
 
-       if (tape->chrdev_direction == idetape_direction_read) {
-               /*
-                *      We have a read-ahead buffer. Scan it for crossed
-                *      filemarks.
-                */
-               tape->merge_stage_size = 0;
-               if (test_and_clear_bit(IDETAPE_FILEMARK, &tape->flags))
+       if (tape->chrdev_dir == IDETAPE_DIR_READ) {
+               tape->merge_bh_size = 0;
+               if (test_and_clear_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags))
                        ++count;
-               while (tape->first_stage != NULL) {
-                       if (count == mt_count) {
-                               if (mt_op == MTFSFM)
-                                       set_bit(IDETAPE_FILEMARK, &tape->flags);
-                               return 0;
-                       }
-                       spin_lock_irqsave(&tape->spinlock, flags);
-                       if (tape->first_stage == tape->active_stage) {
-                               /*
-                                *      We have reached the active stage in the read pipeline.
-                                *      There is no point in allowing the drive to continue
-                                *      reading any farther, so we stop the pipeline.
-                                *
-                                *      This section should be moved to a separate subroutine,
-                                *      because a similar function is performed in
-                                *      __idetape_discard_read_pipeline(), for example.
-                                */
-                               tape->next_stage = NULL;
-                               spin_unlock_irqrestore(&tape->spinlock, flags);
-                               idetape_wait_first_stage(drive);
-                               tape->next_stage = tape->first_stage->next;
-                       } else
-                               spin_unlock_irqrestore(&tape->spinlock, flags);
-                       if (tape->first_stage->rq.errors == IDETAPE_ERROR_FILEMARK)
-                               ++count;
-                       idetape_remove_stage_head(drive);
-               }
-               idetape_discard_read_pipeline(drive, 0);
+               ide_tape_discard_merge_buffer(drive, 0);
        }
 
-       /*
-        *      The filemark was not found in our internal pipeline.
-        *      Now we can issue the space command.
-        */
        switch (mt_op) {
-               case MTFSF:
-               case MTBSF:
-                       idetape_create_space_cmd(&pc,mt_count-count,IDETAPE_SPACE_OVER_FILEMARK);
-                       return (idetape_queue_pc_tail(drive, &pc));
-               case MTFSFM:
-               case MTBSFM:
-                       if (!sprev)
-                               return (-EIO);
-                       retval = idetape_space_over_filemarks(drive, MTFSF, mt_count-count);
-                       if (retval) return (retval);
-                       count = (MTBSFM == mt_op ? 1 : -1);
-                       return (idetape_space_over_filemarks(drive, MTFSF, count));
-               default:
-                       printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",mt_op);
-                       return (-EIO);
+       case MTFSF:
+       case MTBSF:
+               idetape_create_space_cmd(&pc, mt_count - count,
+                                        IDETAPE_SPACE_OVER_FILEMARK);
+               return ide_queue_pc_tail(drive, disk, &pc);
+       case MTFSFM:
+       case MTBSFM:
+               if (!sprev)
+                       return -EIO;
+               retval = idetape_space_over_filemarks(drive, MTFSF,
+                                                     mt_count - count);
+               if (retval)
+                       return retval;
+               count = (MTBSFM == mt_op ? 1 : -1);
+               return idetape_space_over_filemarks(drive, MTFSF, count);
+       default:
+               printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",
+                               mt_op);
+               return -EIO;
        }
 }
 
-
 /*
- *     Our character device read / write functions.
+ * Our character device read / write functions.
  *
- *     The tape is optimized to maximize throughput when it is transferring
- *     an integral number of the "continuous transfer limit", which is
- *     a parameter of the specific tape (26 KB on my particular tape).
- *      (32 kB for Onstream)
+ * The tape is optimized to maximize throughput when it is transferring an
+ * integral number of the "continuous transfer limit", which is a parameter of
+ * the specific tape (26kB on my particular tape, 32kB for Onstream).
  *
- *     As of version 1.3 of the driver, the character device provides an
- *     abstract continuous view of the media - any mix of block sizes (even 1
- *     byte) on the same backup/restore procedure is supported. The driver
- *     will internally convert the requests to the recommended transfer unit,
- *     so that an unmatch between the user's block size to the recommended
- *     size will only result in a (slightly) increased driver overhead, but
- *     will no longer hit performance.
- *      This is not applicable to Onstream.
+ * As of version 1.3 of the driver, the character device provides an abstract
+ * continuous view of the media - any mix of block sizes (even 1 byte) on the
+ * same backup/restore procedure is supported. The driver will internally
+ * convert the requests to the recommended transfer unit, so that an unmatch
+ * between the user's block size to the recommended size will only result in a
+ * (slightly) increased driver overhead, but will no longer hit performance.
+ * This is not applicable to Onstream.
  */
-static ssize_t idetape_chrdev_read (struct file *file, char __user *buf,
-                                   size_t count, loff_t *ppos)
+static ssize_t idetape_chrdev_read(struct file *file, char __user *buf,
+                                  size_t count, loff_t *ppos)
 {
-       struct ide_tape_obj *tape = ide_tape_f(file);
+       struct ide_tape_obj *tape = file->private_data;
        ide_drive_t *drive = tape->drive;
-       ssize_t bytes_read,temp, actually_read = 0, rc;
+       ssize_t bytes_read, temp, actually_read = 0, rc;
        ssize_t ret = 0;
        u16 ctl = *(u16 *)&tape->caps[12];
 
-#if IDETAPE_DEBUG_LOG
-       if (tape->debug_level >= 3)
-               printk(KERN_INFO "ide-tape: Reached idetape_chrdev_read, count %Zd\n", count);
-#endif /* IDETAPE_DEBUG_LOG */
-
-       if (tape->chrdev_direction != idetape_direction_read) {
-               if (test_bit(IDETAPE_DETECT_BS, &tape->flags))
-                       if (count > tape->tape_block_size &&
-                           (count % tape->tape_block_size) == 0)
-                               tape->user_bs_factor = count / tape->tape_block_size;
+       debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count);
+
+       if (tape->chrdev_dir != IDETAPE_DIR_READ) {
+               if (test_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags))
+                       if (count > tape->blk_size &&
+                           (count % tape->blk_size) == 0)
+                               tape->user_bs_factor = count / tape->blk_size;
        }
-       if ((rc = idetape_initiate_read(drive, tape->max_stages)) < 0)
+       rc = idetape_init_read(drive);
+       if (rc < 0)
                return rc;
        if (count == 0)
                return (0);
-       if (tape->merge_stage_size) {
-               actually_read = min((unsigned int)(tape->merge_stage_size), (unsigned int)count);
-               if (idetape_copy_stage_to_user(tape, buf, tape->merge_stage, actually_read))
+       if (tape->merge_bh_size) {
+               actually_read = min((unsigned int)(tape->merge_bh_size),
+                                   (unsigned int)count);
+               if (idetape_copy_stage_to_user(tape, buf, actually_read))
                        ret = -EFAULT;
                buf += actually_read;
-               tape->merge_stage_size -= actually_read;
+               tape->merge_bh_size -= actually_read;
                count -= actually_read;
        }
-       while (count >= tape->stage_size) {
+       while (count >= tape->buffer_size) {
                bytes_read = idetape_add_chrdev_read_request(drive, ctl);
                if (bytes_read <= 0)
                        goto finish;
-               if (idetape_copy_stage_to_user(tape, buf, tape->merge_stage, bytes_read))
+               if (idetape_copy_stage_to_user(tape, buf, bytes_read))
                        ret = -EFAULT;
                buf += bytes_read;
                count -= bytes_read;
@@ -3112,28 +1580,26 @@ static ssize_t idetape_chrdev_read (struct file *file, char __user *buf,
                if (bytes_read <= 0)
                        goto finish;
                temp = min((unsigned long)count, (unsigned long)bytes_read);
-               if (idetape_copy_stage_to_user(tape, buf, tape->merge_stage, temp))
+               if (idetape_copy_stage_to_user(tape, buf, temp))
                        ret = -EFAULT;
                actually_read += temp;
-               tape->merge_stage_size = bytes_read-temp;
+               tape->merge_bh_size = bytes_read-temp;
        }
 finish:
-       if (!actually_read && test_bit(IDETAPE_FILEMARK, &tape->flags)) {
-#if IDETAPE_DEBUG_LOG
-               if (tape->debug_level >= 2)
-                       printk(KERN_INFO "ide-tape: %s: spacing over filemark\n", tape->name);
-#endif
+       if (!actually_read && test_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) {
+               debug_log(DBG_SENSE, "%s: spacing over filemark\n", tape->name);
+
                idetape_space_over_filemarks(drive, MTFSF, 1);
                return 0;
        }
 
-       return (ret) ? ret : actually_read;
+       return ret ? ret : actually_read;
 }
 
-static ssize_t idetape_chrdev_write (struct file *file, const char __user *buf,
+static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf,
                                     size_t count, loff_t *ppos)
 {
-       struct ide_tape_obj *tape = ide_tape_f(file);
+       struct ide_tape_obj *tape = file->private_data;
        ide_drive_t *drive = tape->drive;
        ssize_t actually_written = 0;
        ssize_t ret = 0;
@@ -3143,94 +1609,93 @@ static ssize_t idetape_chrdev_write (struct file *file, const char __user *buf,
        if (tape->write_prot)
                return -EACCES;
 
-#if IDETAPE_DEBUG_LOG
-       if (tape->debug_level >= 3)
-               printk(KERN_INFO "ide-tape: Reached idetape_chrdev_write, "
-                       "count %Zd\n", count);
-#endif /* IDETAPE_DEBUG_LOG */
+       debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count);
 
        /* Initialize write operation */
-       if (tape->chrdev_direction != idetape_direction_write) {
-               if (tape->chrdev_direction == idetape_direction_read)
-                       idetape_discard_read_pipeline(drive, 1);
-               if (tape->merge_stage || tape->merge_stage_size) {
-                       printk(KERN_ERR "ide-tape: merge_stage_size "
+       if (tape->chrdev_dir != IDETAPE_DIR_WRITE) {
+               if (tape->chrdev_dir == IDETAPE_DIR_READ)
+                       ide_tape_discard_merge_buffer(drive, 1);
+               if (tape->merge_bh || tape->merge_bh_size) {
+                       printk(KERN_ERR "ide-tape: merge_bh_size "
                                "should be 0 now\n");
-                       tape->merge_stage_size = 0;
+                       tape->merge_bh_size = 0;
                }
-               if ((tape->merge_stage = __idetape_kmalloc_stage(tape, 0, 0)) == NULL)
+               tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0);
+               if (!tape->merge_bh)
                        return -ENOMEM;
-               tape->chrdev_direction = idetape_direction_write;
-               idetape_init_merge_stage(tape);
+               tape->chrdev_dir = IDETAPE_DIR_WRITE;
+               idetape_init_merge_buffer(tape);
 
                /*
-                *      Issue a write 0 command to ensure that DSC handshake
-                *      is switched from completion mode to buffer available
-                *      mode.
-                *      No point in issuing this if DSC overlap isn't supported,
-                *      some drives (Seagate STT3401A) will return an error.
+                * Issue a write 0 command to ensure that DSC handshake is
+                * switched from completion mode to buffer available mode. No
+                * point in issuing this if DSC overlap isn't supported, some
+                * drives (Seagate STT3401A) will return an error.
                 */
-               if (drive->dsc_overlap) {
-                       ssize_t retval = idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, 0, tape->merge_stage->bh);
+               if (drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) {
+                       ssize_t retval = idetape_queue_rw_tail(drive,
+                                                       REQ_IDETAPE_WRITE, 0,
+                                                       tape->merge_bh);
                        if (retval < 0) {
-                               __idetape_kfree_stage(tape->merge_stage);
-                               tape->merge_stage = NULL;
-                               tape->chrdev_direction = idetape_direction_none;
+                               ide_tape_kfree_buffer(tape);
+                               tape->merge_bh = NULL;
+                               tape->chrdev_dir = IDETAPE_DIR_NONE;
                                return retval;
                        }
                }
        }
        if (count == 0)
                return (0);
-       if (tape->restart_speed_control_req)
-               idetape_restart_speed_control(drive);
-       if (tape->merge_stage_size) {
-               if (tape->merge_stage_size >= tape->stage_size) {
-                       printk(KERN_ERR "ide-tape: bug: merge buffer too big\n");
-                       tape->merge_stage_size = 0;
+       if (tape->merge_bh_size) {
+               if (tape->merge_bh_size >= tape->buffer_size) {
+                       printk(KERN_ERR "ide-tape: bug: merge buf too big\n");
+                       tape->merge_bh_size = 0;
                }
-               actually_written = min((unsigned int)(tape->stage_size - tape->merge_stage_size), (unsigned int)count);
-               if (idetape_copy_stage_from_user(tape, tape->merge_stage, buf, actually_written))
+               actually_written = min((unsigned int)
+                               (tape->buffer_size - tape->merge_bh_size),
+                               (unsigned int)count);
+               if (idetape_copy_stage_from_user(tape, buf, actually_written))
                                ret = -EFAULT;
                buf += actually_written;
-               tape->merge_stage_size += actually_written;
+               tape->merge_bh_size += actually_written;
                count -= actually_written;
 
-               if (tape->merge_stage_size == tape->stage_size) {
+               if (tape->merge_bh_size == tape->buffer_size) {
                        ssize_t retval;
-                       tape->merge_stage_size = 0;
+                       tape->merge_bh_size = 0;
                        retval = idetape_add_chrdev_write_request(drive, ctl);
                        if (retval <= 0)
                                return (retval);
                }
        }
-       while (count >= tape->stage_size) {
+       while (count >= tape->buffer_size) {
                ssize_t retval;
-               if (idetape_copy_stage_from_user(tape, tape->merge_stage, buf, tape->stage_size))
+               if (idetape_copy_stage_from_user(tape, buf, tape->buffer_size))
                        ret = -EFAULT;
-               buf += tape->stage_size;
-               count -= tape->stage_size;
+               buf += tape->buffer_size;
+               count -= tape->buffer_size;
                retval = idetape_add_chrdev_write_request(drive, ctl);
-               actually_written += tape->stage_size;
+               actually_written += tape->buffer_size;
                if (retval <= 0)
                        return (retval);
        }
        if (count) {
                actually_written += count;
-               if (idetape_copy_stage_from_user(tape, tape->merge_stage, buf, count))
+               if (idetape_copy_stage_from_user(tape, buf, count))
                        ret = -EFAULT;
-               tape->merge_stage_size += count;
+               tape->merge_bh_size += count;
        }
-       return (ret) ? ret : actually_written;
+       return ret ? ret : actually_written;
 }
 
-static int idetape_write_filemark (ide_drive_t *drive)
+static int idetape_write_filemark(ide_drive_t *drive)
 {
-       idetape_pc_t pc;
+       struct ide_tape_obj *tape = drive->driver_data;
+       struct ide_atapi_pc pc;
 
        /* Write a filemark */
        idetape_create_write_filemark_cmd(drive, &pc, 1);
-       if (idetape_queue_pc_tail(drive, &pc)) {
+       if (ide_queue_pc_tail(drive, tape->disk, &pc)) {
                printk(KERN_ERR "ide-tape: Couldn't write a filemark\n");
                return -EIO;
        }
@@ -3238,256 +1703,183 @@ static int idetape_write_filemark (ide_drive_t *drive)
 }
 
 /*
- *     idetape_mtioctop is called from idetape_chrdev_ioctl when
- *     the general mtio MTIOCTOP ioctl is requested.
- *
- *     We currently support the following mtio.h operations:
- *
- *     MTFSF   -       Space over mt_count filemarks in the positive direction.
- *                     The tape is positioned after the last spaced filemark.
- *
- *     MTFSFM  -       Same as MTFSF, but the tape is positioned before the
- *                     last filemark.
- *
- *     MTBSF   -       Steps background over mt_count filemarks, tape is
- *                     positioned before the last filemark.
- *
- *     MTBSFM  -       Like MTBSF, only tape is positioned after the last filemark.
- *
- *     Note:
- *
- *             MTBSF and MTBSFM are not supported when the tape doesn't
- *             support spacing over filemarks in the reverse direction.
- *             In this case, MTFSFM is also usually not supported (it is
- *             supported in the rare case in which we crossed the filemark
- *             during our read-ahead pipelined operation mode).
- *             
- *     MTWEOF  -       Writes mt_count filemarks. Tape is positioned after
- *                     the last written filemark.
- *
- *     MTREW   -       Rewinds tape.
- *
- *     MTLOAD  -       Loads the tape.
- *
- *     MTOFFL  -       Puts the tape drive "Offline": Rewinds the tape and
- *     MTUNLOAD        prevents further access until the media is replaced.
- *
- *     MTNOP   -       Flushes tape buffers.
- *
- *     MTRETEN -       Retension media. This typically consists of one end
- *                     to end pass on the media.
- *
- *     MTEOM   -       Moves to the end of recorded data.
- *
- *     MTERASE -       Erases tape.
- *
- *     MTSETBLK -      Sets the user block size to mt_count bytes. If
- *                     mt_count is 0, we will attempt to autodetect
- *                     the block size.
- *
- *     MTSEEK  -       Positions the tape in a specific block number, where
- *                     each block is assumed to contain which user_block_size
- *                     bytes.
- *
- *     MTSETPART -     Switches to another tape partition.
+ * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is
+ * requested.
  *
- *     MTLOCK -        Locks the tape door.
+ * Note: MTBSF and MTBSFM are not supported when the tape doesn't support
+ * spacing over filemarks in the reverse direction. In this case, MTFSFM is also
+ * usually not supported.
  *
- *     MTUNLOCK -      Unlocks the tape door.
+ * The following commands are currently not supported:
  *
- *     The following commands are currently not supported:
- *
- *     MTFSS, MTBSS, MTWSM, MTSETDENSITY,
- *     MTSETDRVBUFFER, MT_ST_BOOLEANS, MT_ST_WRITE_THRESHOLD.
+ * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS,
+ * MT_ST_WRITE_THRESHOLD.
  */
-static int idetape_mtioctop (ide_drive_t *drive,short mt_op,int mt_count)
+static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count)
 {
        idetape_tape_t *tape = drive->driver_data;
-       idetape_pc_t pc;
-       int i,retval;
+       struct gendisk *disk = tape->disk;
+       struct ide_atapi_pc pc;
+       int i, retval;
+
+       debug_log(DBG_ERR, "Handling MTIOCTOP ioctl: mt_op=%d, mt_count=%d\n",
+                       mt_op, mt_count);
 
-#if IDETAPE_DEBUG_LOG
-       if (tape->debug_level >= 1)
-               printk(KERN_INFO "ide-tape: Handling MTIOCTOP ioctl: "
-                       "mt_op=%d, mt_count=%d\n", mt_op, mt_count);
-#endif /* IDETAPE_DEBUG_LOG */
-       /*
-        *      Commands which need our pipelined read-ahead stages.
-        */
        switch (mt_op) {
-               case MTFSF:
-               case MTFSFM:
-               case MTBSF:
-               case MTBSFM:
-                       if (!mt_count)
-                               return (0);
-                       return (idetape_space_over_filemarks(drive,mt_op,mt_count));
-               default:
-                       break;
+       case MTFSF:
+       case MTFSFM:
+       case MTBSF:
+       case MTBSFM:
+               if (!mt_count)
+                       return 0;
+               return idetape_space_over_filemarks(drive, mt_op, mt_count);
+       default:
+               break;
        }
+
        switch (mt_op) {
-               case MTWEOF:
-                       if (tape->write_prot)
-                               return -EACCES;
-                       idetape_discard_read_pipeline(drive, 1);
-                       for (i = 0; i < mt_count; i++) {
-                               retval = idetape_write_filemark(drive);
-                               if (retval)
-                                       return retval;
-                       }
-                       return (0);
-               case MTREW:
-                       idetape_discard_read_pipeline(drive, 0);
-                       if (idetape_rewind_tape(drive))
+       case MTWEOF:
+               if (tape->write_prot)
+                       return -EACCES;
+               ide_tape_discard_merge_buffer(drive, 1);
+               for (i = 0; i < mt_count; i++) {
+                       retval = idetape_write_filemark(drive);
+                       if (retval)
+                               return retval;
+               }
+               return 0;
+       case MTREW:
+               ide_tape_discard_merge_buffer(drive, 0);
+               if (idetape_rewind_tape(drive))
+                       return -EIO;
+               return 0;
+       case MTLOAD:
+               ide_tape_discard_merge_buffer(drive, 0);
+               return ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK);
+       case MTUNLOAD:
+       case MTOFFL:
+               /*
+                * If door is locked, attempt to unlock before
+                * attempting to eject.
+                */
+               if (tape->door_locked) {
+                       if (!ide_set_media_lock(drive, disk, 0))
+                               tape->door_locked = DOOR_UNLOCKED;
+               }
+               ide_tape_discard_merge_buffer(drive, 0);
+               retval = ide_do_start_stop(drive, disk, !IDETAPE_LU_LOAD_MASK);
+               if (!retval)
+                       clear_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags);
+               return retval;
+       case MTNOP:
+               ide_tape_discard_merge_buffer(drive, 0);
+               return idetape_flush_tape_buffers(drive);
+       case MTRETEN:
+               ide_tape_discard_merge_buffer(drive, 0);
+               return ide_do_start_stop(drive, disk,
+                       IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK);
+       case MTEOM:
+               idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD);
+               return ide_queue_pc_tail(drive, disk, &pc);
+       case MTERASE:
+               (void)idetape_rewind_tape(drive);
+               idetape_create_erase_cmd(&pc);
+               return ide_queue_pc_tail(drive, disk, &pc);
+       case MTSETBLK:
+               if (mt_count) {
+                       if (mt_count < tape->blk_size ||
+                           mt_count % tape->blk_size)
                                return -EIO;
-                       return 0;
-               case MTLOAD:
-                       idetape_discard_read_pipeline(drive, 0);
-                       idetape_create_load_unload_cmd(drive, &pc, IDETAPE_LU_LOAD_MASK);
-                       return (idetape_queue_pc_tail(drive, &pc));
-               case MTUNLOAD:
-               case MTOFFL:
-                       /*
-                        * If door is locked, attempt to unlock before
-                        * attempting to eject.
-                        */
-                       if (tape->door_locked) {
-                               if (idetape_create_prevent_cmd(drive, &pc, 0))
-                                       if (!idetape_queue_pc_tail(drive, &pc))
-                                               tape->door_locked = DOOR_UNLOCKED;
-                       }
-                       idetape_discard_read_pipeline(drive, 0);
-                       idetape_create_load_unload_cmd(drive, &pc,!IDETAPE_LU_LOAD_MASK);
-                       retval = idetape_queue_pc_tail(drive, &pc);
-                       if (!retval)
-                               clear_bit(IDETAPE_MEDIUM_PRESENT, &tape->flags);
+                       tape->user_bs_factor = mt_count / tape->blk_size;
+                       clear_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags);
+               } else
+                       set_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags);
+               return 0;
+       case MTSEEK:
+               ide_tape_discard_merge_buffer(drive, 0);
+               return idetape_position_tape(drive,
+                       mt_count * tape->user_bs_factor, tape->partition, 0);
+       case MTSETPART:
+               ide_tape_discard_merge_buffer(drive, 0);
+               return idetape_position_tape(drive, 0, mt_count, 0);
+       case MTFSR:
+       case MTBSR:
+       case MTLOCK:
+               retval = ide_set_media_lock(drive, disk, 1);
+               if (retval)
                        return retval;
-               case MTNOP:
-                       idetape_discard_read_pipeline(drive, 0);
-                       return (idetape_flush_tape_buffers(drive));
-               case MTRETEN:
-                       idetape_discard_read_pipeline(drive, 0);
-                       idetape_create_load_unload_cmd(drive, &pc,IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK);
-                       return (idetape_queue_pc_tail(drive, &pc));
-               case MTEOM:
-                       idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD);
-                       return (idetape_queue_pc_tail(drive, &pc));
-               case MTERASE:
-                       (void) idetape_rewind_tape(drive);
-                       idetape_create_erase_cmd(&pc);
-                       return (idetape_queue_pc_tail(drive, &pc));
-               case MTSETBLK:
-                       if (mt_count) {
-                               if (mt_count < tape->tape_block_size || mt_count % tape->tape_block_size)
-                                       return -EIO;
-                               tape->user_bs_factor = mt_count / tape->tape_block_size;
-                               clear_bit(IDETAPE_DETECT_BS, &tape->flags);
-                       } else
-                               set_bit(IDETAPE_DETECT_BS, &tape->flags);
-                       return 0;
-               case MTSEEK:
-                       idetape_discard_read_pipeline(drive, 0);
-                       return idetape_position_tape(drive, mt_count * tape->user_bs_factor, tape->partition, 0);
-               case MTSETPART:
-                       idetape_discard_read_pipeline(drive, 0);
-                       return (idetape_position_tape(drive, 0, mt_count, 0));
-               case MTFSR:
-               case MTBSR:
-               case MTLOCK:
-                       if (!idetape_create_prevent_cmd(drive, &pc, 1))
-                               return 0;
-                       retval = idetape_queue_pc_tail(drive, &pc);
-                       if (retval) return retval;
-                       tape->door_locked = DOOR_EXPLICITLY_LOCKED;
-                       return 0;
-               case MTUNLOCK:
-                       if (!idetape_create_prevent_cmd(drive, &pc, 0))
-                               return 0;
-                       retval = idetape_queue_pc_tail(drive, &pc);
-                       if (retval) return retval;
-                       tape->door_locked = DOOR_UNLOCKED;
-                       return 0;
-               default:
-                       printk(KERN_ERR "ide-tape: MTIO operation %d not "
-                               "supported\n", mt_op);
-                       return (-EIO);
+               tape->door_locked = DOOR_EXPLICITLY_LOCKED;
+               return 0;
+       case MTUNLOCK:
+               retval = ide_set_media_lock(drive, disk, 0);
+               if (retval)
+                       return retval;
+               tape->door_locked = DOOR_UNLOCKED;
+               return 0;
+       default:
+               printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",
+                               mt_op);
+               return -EIO;
        }
 }
 
 /*
- *     Our character device ioctls.
- *
- *     General mtio.h magnetic io commands are supported here, and not in
- *     the corresponding block interface.
- *
- *     The following ioctls are supported:
- *
- *     MTIOCTOP -      Refer to idetape_mtioctop for detailed description.
- *
- *     MTIOCGET -      The mt_dsreg field in the returned mtget structure
- *                     will be set to (user block size in bytes <<
- *                     MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK.
- *
- *                     The mt_blkno is set to the current user block number.
- *                     The other mtget fields are not supported.
- *
- *     MTIOCPOS -      The current tape "block position" is returned. We
- *                     assume that each block contains user_block_size
- *                     bytes.
- *
- *     Our own ide-tape ioctls are supported on both interfaces.
+ * Our character device ioctls. General mtio.h magnetic io commands are
+ * supported here, and not in the corresponding block interface. Our own
+ * ide-tape ioctls are supported on both interfaces.
  */
-static int idetape_chrdev_ioctl (struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
+static int idetape_chrdev_ioctl(struct inode *inode, struct file *file,
+                               unsigned int cmd, unsigned long arg)
 {
-       struct ide_tape_obj *tape = ide_tape_f(file);
+       struct ide_tape_obj *tape = file->private_data;
        ide_drive_t *drive = tape->drive;
        struct mtop mtop;
        struct mtget mtget;
        struct mtpos mtpos;
-       int block_offset = 0, position = tape->first_frame_position;
+       int block_offset = 0, position = tape->first_frame;
        void __user *argp = (void __user *)arg;
 
-#if IDETAPE_DEBUG_LOG
-       if (tape->debug_level >= 3)
-               printk(KERN_INFO "ide-tape: Reached idetape_chrdev_ioctl, "
-                       "cmd=%u\n", cmd);
-#endif /* IDETAPE_DEBUG_LOG */
-
-       tape->restart_speed_control_req = 1;
-       if (tape->chrdev_direction == idetape_direction_write) {
-               idetape_empty_write_pipeline(drive);
+       debug_log(DBG_CHRDEV, "Enter %s, cmd=%u\n", __func__, cmd);
+
+       if (tape->chrdev_dir == IDETAPE_DIR_WRITE) {
+               ide_tape_flush_merge_buffer(drive);
                idetape_flush_tape_buffers(drive);
        }
        if (cmd == MTIOCGET || cmd == MTIOCPOS) {
-               block_offset = idetape_pipeline_size(drive) / (tape->tape_block_size * tape->user_bs_factor);
-               if ((position = idetape_read_position(drive)) < 0)
+               block_offset = tape->merge_bh_size /
+                       (tape->blk_size * tape->user_bs_factor);
+               position = idetape_read_position(drive);
+               if (position < 0)
                        return -EIO;
        }
        switch (cmd) {
-               case MTIOCTOP:
-                       if (copy_from_user(&mtop, argp, sizeof (struct mtop)))
-                               return -EFAULT;
-                       return (idetape_mtioctop(drive,mtop.mt_op,mtop.mt_count));
-               case MTIOCGET:
-                       memset(&mtget, 0, sizeof (struct mtget));
-                       mtget.mt_type = MT_ISSCSI2;
-                       mtget.mt_blkno = position / tape->user_bs_factor - block_offset;
-                       mtget.mt_dsreg = ((tape->tape_block_size * tape->user_bs_factor) << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK;
-                       if (tape->drv_write_prot) {
-                               mtget.mt_gstat |= GMT_WR_PROT(0xffffffff);
-                       }
-                       if (copy_to_user(argp, &mtget, sizeof(struct mtget)))
-                               return -EFAULT;
-                       return 0;
-               case MTIOCPOS:
-                       mtpos.mt_blkno = position / tape->user_bs_factor - block_offset;
-                       if (copy_to_user(argp, &mtpos, sizeof(struct mtpos)))
-                               return -EFAULT;
-                       return 0;
-               default:
-                       if (tape->chrdev_direction == idetape_direction_read)
-                               idetape_discard_read_pipeline(drive, 1);
-                       return idetape_blkdev_ioctl(drive, cmd, arg);
+       case MTIOCTOP:
+               if (copy_from_user(&mtop, argp, sizeof(struct mtop)))
+                       return -EFAULT;
+               return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count);
+       case MTIOCGET:
+               memset(&mtget, 0, sizeof(struct mtget));
+               mtget.mt_type = MT_ISSCSI2;
+               mtget.mt_blkno = position / tape->user_bs_factor - block_offset;
+               mtget.mt_dsreg =
+                       ((tape->blk_size * tape->user_bs_factor)
+                        << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK;
+
+               if (tape->drv_write_prot)
+                       mtget.mt_gstat |= GMT_WR_PROT(0xffffffff);
+
+               if (copy_to_user(argp, &mtget, sizeof(struct mtget)))
+                       return -EFAULT;
+               return 0;
+       case MTIOCPOS:
+               mtpos.mt_blkno = position / tape->user_bs_factor - block_offset;
+               if (copy_to_user(argp, &mtpos, sizeof(struct mtpos)))
+                       return -EFAULT;
+               return 0;
+       default:
+               if (tape->chrdev_dir == IDETAPE_DIR_READ)
+                       ide_tape_discard_merge_buffer(drive, 1);
+               return idetape_blkdev_ioctl(drive, cmd, arg);
        }
 }
 
@@ -3498,35 +1890,43 @@ static int idetape_chrdev_ioctl (struct inode *inode, struct file *file, unsigne
 static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive)
 {
        idetape_tape_t *tape = drive->driver_data;
-       idetape_pc_t pc;
+       struct ide_atapi_pc pc;
 
        idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR);
-       if (idetape_queue_pc_tail(drive, &pc)) {
+       if (ide_queue_pc_tail(drive, tape->disk, &pc)) {
                printk(KERN_ERR "ide-tape: Can't get block descriptor\n");
-               if (tape->tape_block_size == 0) {
+               if (tape->blk_size == 0) {
                        printk(KERN_WARNING "ide-tape: Cannot deal with zero "
                                            "block size, assuming 32k\n");
-                       tape->tape_block_size = 32768;
+                       tape->blk_size = 32768;
                }
                return;
        }
-       tape->tape_block_size = (pc.buffer[4 + 5] << 16) +
-                               (pc.buffer[4 + 6] << 8)  +
-                                pc.buffer[4 + 7];
-       tape->drv_write_prot = (pc.buffer[2] & 0x80) >> 7;
+       tape->blk_size = (pc.buf[4 + 5] << 16) +
+                               (pc.buf[4 + 6] << 8)  +
+                                pc.buf[4 + 7];
+       tape->drv_write_prot = (pc.buf[2] & 0x80) >> 7;
 }
 
-/*
- *     Our character device open function.
- */
-static int idetape_chrdev_open (struct inode *inode, struct file *filp)
+static int idetape_chrdev_open(struct inode *inode, struct file *filp)
 {
        unsigned int minor = iminor(inode), i = minor & ~0xc0;
        ide_drive_t *drive;
        idetape_tape_t *tape;
-       idetape_pc_t pc;
        int retval;
 
+       if (i >= MAX_HWIFS * MAX_DRIVES)
+               return -ENXIO;
+
+       lock_kernel();
+       tape = ide_tape_chrdev_get(i);
+       if (!tape) {
+               unlock_kernel();
+               return -ENXIO;
+       }
+
+       debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
+
        /*
         * We really want to do nonseekable_open(inode, filp); here, but some
         * versions of tar incorrectly call lseek on tapes and bail out if that
@@ -3534,39 +1934,26 @@ static int idetape_chrdev_open (struct inode *inode, struct file *filp)
         */
        filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
 
-#if IDETAPE_DEBUG_LOG
-       printk(KERN_INFO "ide-tape: Reached idetape_chrdev_open\n");
-#endif /* IDETAPE_DEBUG_LOG */
-       
-       if (i >= MAX_HWIFS * MAX_DRIVES)
-               return -ENXIO;
-
-       if (!(tape = ide_tape_chrdev_get(i)))
-               return -ENXIO;
-
        drive = tape->drive;
 
        filp->private_data = tape;
 
-       if (test_and_set_bit(IDETAPE_BUSY, &tape->flags)) {
+       if (test_and_set_bit(IDE_AFLAG_BUSY, &drive->atapi_flags)) {
                retval = -EBUSY;
                goto out_put_tape;
        }
 
        retval = idetape_wait_ready(drive, 60 * HZ);
        if (retval) {
-               clear_bit(IDETAPE_BUSY, &tape->flags);
+               clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags);
                printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name);
                goto out_put_tape;
        }
 
        idetape_read_position(drive);
-       if (!test_bit(IDETAPE_ADDRESS_VALID, &tape->flags))
+       if (!test_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags))
                (void)idetape_rewind_tape(drive);
 
-       if (tape->chrdev_direction != idetape_direction_read)
-               clear_bit(IDETAPE_PIPELINE_ERROR, &tape->flags);
-
        /* Read block size and write protect status from drive. */
        ide_tape_get_bsize_from_bdesc(drive);
 
@@ -3580,340 +1967,288 @@ static int idetape_chrdev_open (struct inode *inode, struct file *filp)
        if (tape->write_prot) {
                if ((filp->f_flags & O_ACCMODE) == O_WRONLY ||
                    (filp->f_flags & O_ACCMODE) == O_RDWR) {
-                       clear_bit(IDETAPE_BUSY, &tape->flags);
+                       clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags);
                        retval = -EROFS;
                        goto out_put_tape;
                }
        }
 
-       /*
-        * Lock the tape drive door so user can't eject.
-        */
-       if (tape->chrdev_direction == idetape_direction_none) {
-               if (idetape_create_prevent_cmd(drive, &pc, 1)) {
-                       if (!idetape_queue_pc_tail(drive, &pc)) {
-                               if (tape->door_locked != DOOR_EXPLICITLY_LOCKED)
-                                       tape->door_locked = DOOR_LOCKED;
-                       }
+       /* Lock the tape drive door so user can't eject. */
+       if (tape->chrdev_dir == IDETAPE_DIR_NONE) {
+               if (!ide_set_media_lock(drive, tape->disk, 1)) {
+                       if (tape->door_locked != DOOR_EXPLICITLY_LOCKED)
+                               tape->door_locked = DOOR_LOCKED;
                }
        }
-       idetape_restart_speed_control(drive);
-       tape->restart_speed_control_req = 0;
+       unlock_kernel();
        return 0;
 
 out_put_tape:
        ide_tape_put(tape);
+       unlock_kernel();
        return retval;
 }
 
-static void idetape_write_release (ide_drive_t *drive, unsigned int minor)
+static void idetape_write_release(ide_drive_t *drive, unsigned int minor)
 {
        idetape_tape_t *tape = drive->driver_data;
 
-       idetape_empty_write_pipeline(drive);
-       tape->merge_stage = __idetape_kmalloc_stage(tape, 1, 0);
-       if (tape->merge_stage != NULL) {
-               idetape_pad_zeros(drive, tape->tape_block_size * (tape->user_bs_factor - 1));
-               __idetape_kfree_stage(tape->merge_stage);
-               tape->merge_stage = NULL;
+       ide_tape_flush_merge_buffer(drive);
+       tape->merge_bh = ide_tape_kmalloc_buffer(tape, 1, 0);
+       if (tape->merge_bh != NULL) {
+               idetape_pad_zeros(drive, tape->blk_size *
+                               (tape->user_bs_factor - 1));
+               ide_tape_kfree_buffer(tape);
+               tape->merge_bh = NULL;
        }
        idetape_write_filemark(drive);
        idetape_flush_tape_buffers(drive);
        idetape_flush_tape_buffers(drive);
 }
 
-/*
- *     Our character device release function.
- */
-static int idetape_chrdev_release (struct inode *inode, struct file *filp)
+static int idetape_chrdev_release(struct inode *inode, struct file *filp)
 {
-       struct ide_tape_obj *tape = ide_tape_f(filp);
+       struct ide_tape_obj *tape = filp->private_data;
        ide_drive_t *drive = tape->drive;
-       idetape_pc_t pc;
        unsigned int minor = iminor(inode);
 
        lock_kernel();
        tape = drive->driver_data;
-#if IDETAPE_DEBUG_LOG
-       if (tape->debug_level >= 3)
-               printk(KERN_INFO "ide-tape: Reached idetape_chrdev_release\n");
-#endif /* IDETAPE_DEBUG_LOG */
 
-       if (tape->chrdev_direction == idetape_direction_write)
+       debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
+
+       if (tape->chrdev_dir == IDETAPE_DIR_WRITE)
                idetape_write_release(drive, minor);
-       if (tape->chrdev_direction == idetape_direction_read) {
+       if (tape->chrdev_dir == IDETAPE_DIR_READ) {
                if (minor < 128)
-                       idetape_discard_read_pipeline(drive, 1);
-               else
-                       idetape_wait_for_pipeline(drive);
+                       ide_tape_discard_merge_buffer(drive, 1);
        }
-       if (tape->cache_stage != NULL) {
-               __idetape_kfree_stage(tape->cache_stage);
-               tape->cache_stage = NULL;
-       }
-       if (minor < 128 && test_bit(IDETAPE_MEDIUM_PRESENT, &tape->flags))
+
+       if (minor < 128 && test_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags))
                (void) idetape_rewind_tape(drive);
-       if (tape->chrdev_direction == idetape_direction_none) {
+       if (tape->chrdev_dir == IDETAPE_DIR_NONE) {
                if (tape->door_locked == DOOR_LOCKED) {
-                       if (idetape_create_prevent_cmd(drive, &pc, 0)) {
-                               if (!idetape_queue_pc_tail(drive, &pc))
-                                       tape->door_locked = DOOR_UNLOCKED;
-                       }
+                       if (!ide_set_media_lock(drive, tape->disk, 0))
+                               tape->door_locked = DOOR_UNLOCKED;
                }
        }
-       clear_bit(IDETAPE_BUSY, &tape->flags);
+       clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags);
        ide_tape_put(tape);
        unlock_kernel();
        return 0;
 }
 
-/*
- *     idetape_identify_device is called to check the contents of the
- *     ATAPI IDENTIFY command results. We return:
- *
- *     1       If the tape can be supported by us, based on the information
- *             we have so far.
- *
- *     0       If this tape driver is not currently supported by us.
- */
-static int idetape_identify_device (ide_drive_t *drive)
-{
-       struct idetape_id_gcw gcw;
-       struct hd_driveid *id = drive->id;
-
-       if (drive->id_read == 0)
-               return 1;
-
-       *((unsigned short *) &gcw) = id->config;
-
-       /* Check that we can support this device */
-
-       if (gcw.protocol != 2)
-               printk(KERN_ERR "ide-tape: Protocol (0x%02x) is not ATAPI\n",
-                               gcw.protocol);
-       else if (gcw.device_type != 1)
-               printk(KERN_ERR "ide-tape: Device type (0x%02x) is not set "
-                               "to tape\n", gcw.device_type);
-       else if (!gcw.removable)
-               printk(KERN_ERR "ide-tape: The removable flag is not set\n");
-       else if (gcw.packet_size != 0) {
-               printk(KERN_ERR "ide-tape: Packet size (0x%02x) is not 12 "
-                               "bytes long\n", gcw.packet_size);
-       } else
-               return 1;
-       return 0;
-}
-
 static void idetape_get_inquiry_results(ide_drive_t *drive)
 {
-       char *r;
        idetape_tape_t *tape = drive->driver_data;
-       idetape_pc_t pc;
+       struct ide_atapi_pc pc;
+       char fw_rev[4], vendor_id[8], product_id[16];
 
        idetape_create_inquiry_cmd(&pc);
-       if (idetape_queue_pc_tail(drive, &pc)) {
+       if (ide_queue_pc_tail(drive, tape->disk, &pc)) {
                printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n",
                                tape->name);
                return;
        }
-       memcpy(tape->vendor_id, &pc.buffer[8], 8);
-       memcpy(tape->product_id, &pc.buffer[16], 16);
-       memcpy(tape->firmware_revision, &pc.buffer[32], 4);
-
-       ide_fixstring(tape->vendor_id, 10, 0);
-       ide_fixstring(tape->product_id, 18, 0);
-       ide_fixstring(tape->firmware_revision, 6, 0);
-       r = tape->firmware_revision;
-       if (*(r + 1) == '.')
-               tape->firmware_revision_num = (*r - '0') * 100 +
-                       (*(r + 2) - '0') * 10 + *(r + 3) - '0';
-       printk(KERN_INFO "ide-tape: %s <-> %s: %s %s rev %s\n",
-                       drive->name, tape->name, tape->vendor_id,
-                       tape->product_id, tape->firmware_revision);
+       memcpy(vendor_id, &pc.buf[8], 8);
+       memcpy(product_id, &pc.buf[16], 16);
+       memcpy(fw_rev, &pc.buf[32], 4);
+
+       ide_fixstring(vendor_id, 8, 0);
+       ide_fixstring(product_id, 16, 0);
+       ide_fixstring(fw_rev, 4, 0);
+
+       printk(KERN_INFO "ide-tape: %s <-> %s: %.8s %.16s rev %.4s\n",
+                       drive->name, tape->name, vendor_id, product_id, fw_rev);
 }
 
 /*
  * Ask the tape about its various parameters. In particular, we will adjust our
  * data transfer buffer        size to the recommended value as returned by the tape.
  */
-static void idetape_get_mode_sense_results (ide_drive_t *drive)
+static void idetape_get_mode_sense_results(ide_drive_t *drive)
 {
        idetape_tape_t *tape = drive->driver_data;
-       idetape_pc_t pc;
+       struct ide_atapi_pc pc;
        u8 *caps;
        u8 speed, max_speed;
 
        idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE);
-       if (idetape_queue_pc_tail(drive, &pc)) {
+       if (ide_queue_pc_tail(drive, tape->disk, &pc)) {
                printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming"
                                " some default values\n");
-               tape->tape_block_size = 512;
+               tape->blk_size = 512;
                put_unaligned(52,   (u16 *)&tape->caps[12]);
                put_unaligned(540,  (u16 *)&tape->caps[14]);
                put_unaligned(6*52, (u16 *)&tape->caps[16]);
                return;
        }
-       caps = pc.buffer + 4 + pc.buffer[3];
+       caps = pc.buf + 4 + pc.buf[3];
 
        /* convert to host order and save for later use */
-       speed = be16_to_cpu(*(u16 *)&caps[14]);
-       max_speed = be16_to_cpu(*(u16 *)&caps[8]);
+       speed = be16_to_cpup((__be16 *)&caps[14]);
+       max_speed = be16_to_cpup((__be16 *)&caps[8]);
 
-       put_unaligned(max_speed, (u16 *)&caps[8]);
-       put_unaligned(be16_to_cpu(*(u16 *)&caps[12]), (u16 *)&caps[12]);
-       put_unaligned(speed, (u16 *)&caps[14]);
-       put_unaligned(be16_to_cpu(*(u16 *)&caps[16]), (u16 *)&caps[16]);
+       *(u16 *)&caps[8] = max_speed;
+       *(u16 *)&caps[12] = be16_to_cpup((__be16 *)&caps[12]);
+       *(u16 *)&caps[14] = speed;
+       *(u16 *)&caps[16] = be16_to_cpup((__be16 *)&caps[16]);
 
        if (!speed) {
                printk(KERN_INFO "ide-tape: %s: invalid tape speed "
                                "(assuming 650KB/sec)\n", drive->name);
-               put_unaligned(650, (u16 *)&caps[14]);
+               *(u16 *)&caps[14] = 650;
        }
        if (!max_speed) {
                printk(KERN_INFO "ide-tape: %s: invalid max_speed "
                                "(assuming 650KB/sec)\n", drive->name);
-               put_unaligned(650, (u16 *)&caps[8]);
+               *(u16 *)&caps[8] = 650;
        }
 
        memcpy(&tape->caps, caps, 20);
+
+       /* device lacks locking support according to capabilities page */
+       if ((caps[6] & 1) == 0)
+               drive->dev_flags &= ~IDE_DFLAG_DOORLOCKING;
+
        if (caps[7] & 0x02)
-               tape->tape_block_size = 512;
+               tape->blk_size = 512;
        else if (caps[7] & 0x04)
-               tape->tape_block_size = 1024;
+               tape->blk_size = 1024;
 }
 
 #ifdef CONFIG_IDE_PROC_FS
-static void idetape_add_settings (ide_drive_t *drive)
-{
-       idetape_tape_t *tape = drive->driver_data;
-
-/*
- *                     drive   setting name            read/write      data type       min                     max                     mul_factor                      div_factor      data pointer                            set function
- */
-       ide_add_setting(drive, "buffer", SETTING_READ, TYPE_SHORT, 0, 0xffff,
-                       1, 2, (u16 *)&tape->caps[16], NULL);
-       ide_add_setting(drive,  "pipeline_min",         SETTING_RW,     TYPE_INT,       1,                      0xffff,                 tape->stage_size / 1024,        1,              &tape->min_pipeline,                    NULL);
-       ide_add_setting(drive,  "pipeline",             SETTING_RW,     TYPE_INT,       1,                      0xffff,                 tape->stage_size / 1024,        1,              &tape->max_stages,                      NULL);
-       ide_add_setting(drive,  "pipeline_max",         SETTING_RW,     TYPE_INT,       1,                      0xffff,                 tape->stage_size / 1024,        1,              &tape->max_pipeline,                    NULL);
-       ide_add_setting(drive,  "pipeline_used",        SETTING_READ,   TYPE_INT,       0,                      0xffff,                 tape->stage_size / 1024,        1,              &tape->nr_stages,                       NULL);
-       ide_add_setting(drive,  "pipeline_pending",     SETTING_READ,   TYPE_INT,       0,                      0xffff,                 tape->stage_size / 1024,        1,              &tape->nr_pending_stages,               NULL);
-       ide_add_setting(drive, "speed", SETTING_READ, TYPE_SHORT, 0, 0xffff,
-                       1, 1, (u16 *)&tape->caps[14], NULL);
-       ide_add_setting(drive,  "stage",                SETTING_READ,   TYPE_INT,       0,                      0xffff,                 1,                              1024,           &tape->stage_size,                      NULL);
-       ide_add_setting(drive,  "tdsc",                 SETTING_RW,     TYPE_INT,       IDETAPE_DSC_RW_MIN,     IDETAPE_DSC_RW_MAX,     1000,                           HZ,             &tape->best_dsc_rw_frequency,           NULL);
-       ide_add_setting(drive,  "dsc_overlap",          SETTING_RW,     TYPE_BYTE,      0,                      1,                      1,                              1,              &drive->dsc_overlap,                    NULL);
-       ide_add_setting(drive,  "pipeline_head_speed_c",SETTING_READ,   TYPE_INT,       0,                      0xffff,                 1,                              1,              &tape->controlled_pipeline_head_speed,  NULL);
-       ide_add_setting(drive,  "pipeline_head_speed_u",SETTING_READ,   TYPE_INT,       0,                      0xffff,                 1,                              1,              &tape->uncontrolled_pipeline_head_speed,NULL);
-       ide_add_setting(drive,  "avg_speed",            SETTING_READ,   TYPE_INT,       0,                      0xffff,                 1,                              1,              &tape->avg_speed,                       NULL);
-       ide_add_setting(drive,  "debug_level",          SETTING_RW,     TYPE_INT,       0,                      0xffff,                 1,                              1,              &tape->debug_level,                     NULL);
-}
-#else
-static inline void idetape_add_settings(ide_drive_t *drive) { ; }
+#define ide_tape_devset_get(name, field) \
+static int get_##name(ide_drive_t *drive) \
+{ \
+       idetape_tape_t *tape = drive->driver_data; \
+       return tape->field; \
+}
+
+#define ide_tape_devset_set(name, field) \
+static int set_##name(ide_drive_t *drive, int arg) \
+{ \
+       idetape_tape_t *tape = drive->driver_data; \
+       tape->field = arg; \
+       return 0; \
+}
+
+#define ide_tape_devset_rw_field(_name, _field) \
+ide_tape_devset_get(_name, _field) \
+ide_tape_devset_set(_name, _field) \
+IDE_DEVSET(_name, DS_SYNC, get_##_name, set_##_name)
+
+#define ide_tape_devset_r_field(_name, _field) \
+ide_tape_devset_get(_name, _field) \
+IDE_DEVSET(_name, 0, get_##_name, NULL)
+
+static int mulf_tdsc(ide_drive_t *drive)       { return 1000; }
+static int divf_tdsc(ide_drive_t *drive)       { return   HZ; }
+static int divf_buffer(ide_drive_t *drive)     { return    2; }
+static int divf_buffer_size(ide_drive_t *drive)        { return 1024; }
+
+ide_devset_rw_flag(dsc_overlap, IDE_DFLAG_DSC_OVERLAP);
+
+ide_tape_devset_rw_field(debug_mask, debug_mask);
+ide_tape_devset_rw_field(tdsc, best_dsc_rw_freq);
+
+ide_tape_devset_r_field(avg_speed, avg_speed);
+ide_tape_devset_r_field(speed, caps[14]);
+ide_tape_devset_r_field(buffer, caps[16]);
+ide_tape_devset_r_field(buffer_size, buffer_size);
+
+static const struct ide_proc_devset idetape_settings[] = {
+       __IDE_PROC_DEVSET(avg_speed,    0, 0xffff, NULL, NULL),
+       __IDE_PROC_DEVSET(buffer,       0, 0xffff, NULL, divf_buffer),
+       __IDE_PROC_DEVSET(buffer_size,  0, 0xffff, NULL, divf_buffer_size),
+       __IDE_PROC_DEVSET(debug_mask,   0, 0xffff, NULL, NULL),
+       __IDE_PROC_DEVSET(dsc_overlap,  0,      1, NULL, NULL),
+       __IDE_PROC_DEVSET(speed,        0, 0xffff, NULL, NULL),
+       __IDE_PROC_DEVSET(tdsc,         IDETAPE_DSC_RW_MIN, IDETAPE_DSC_RW_MAX,
+                                       mulf_tdsc, divf_tdsc),
+       { NULL },
+};
 #endif
 
 /*
- *     ide_setup is called to:
+ * The function below is called to:
  *
- *             1.      Initialize our various state variables.
- *             2.      Ask the tape for its capabilities.
- *             3.      Allocate a buffer which will be used for data
- *                     transfer. The buffer size is chosen based on
- *                     the recommendation which we received in step (2).
+ * 1. Initialize our various state variables.
+ * 2. Ask the tape for its capabilities.
+ * 3. Allocate a buffer which will be used for data transfer. The buffer size
+ * is chosen based on the recommendation which we received in step 2.
  *
- *     Note that at this point ide.c already assigned us an irq, so that
- *     we can queue requests here and wait for their completion.
+ * Note that at this point ide.c already assigned us an irq, so that we can
+ * queue requests here and wait for their completion.
  */
-static void idetape_setup (ide_drive_t *drive, idetape_tape_t *tape, int minor)
+static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor)
 {
-       unsigned long t1, tmid, tn, t;
+       unsigned long t;
        int speed;
-       struct idetape_id_gcw gcw;
-       int stage_size;
-       struct sysinfo si;
+       int buffer_size;
        u16 *ctl = (u16 *)&tape->caps[12];
 
-       spin_lock_init(&tape->spinlock);
-       drive->dsc_overlap = 1;
+       drive->pc_callback       = ide_tape_callback;
+       drive->pc_update_buffers = idetape_update_buffers;
+       drive->pc_io_buffers     = ide_tape_io_buffers;
+
+       spin_lock_init(&tape->lock);
+
+       drive->dev_flags |= IDE_DFLAG_DSC_OVERLAP;
+
        if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) {
                printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n",
                                 tape->name);
-               drive->dsc_overlap = 0;
+               drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP;
        }
+
        /* Seagate Travan drives do not support DSC overlap. */
-       if (strstr(drive->id->model, "Seagate STT3401"))
-               drive->dsc_overlap = 0;
+       if (strstr((char *)&drive->id[ATA_ID_PROD], "Seagate STT3401"))
+               drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP;
+
        tape->minor = minor;
        tape->name[0] = 'h';
        tape->name[1] = 't';
        tape->name[2] = '0' + minor;
-       tape->chrdev_direction = idetape_direction_none;
-       tape->pc = tape->pc_stack;
-       tape->max_insert_speed = 10000;
-       tape->speed_control = 1;
-       *((unsigned short *) &gcw) = drive->id->config;
-       if (gcw.drq_type == 1)
-               set_bit(IDETAPE_DRQ_INTERRUPT, &tape->flags);
-
-       tape->min_pipeline = tape->max_pipeline = tape->max_stages = 10;
-       
+       tape->chrdev_dir = IDETAPE_DIR_NONE;
+
        idetape_get_inquiry_results(drive);
        idetape_get_mode_sense_results(drive);
        ide_tape_get_bsize_from_bdesc(drive);
        tape->user_bs_factor = 1;
-       tape->stage_size = *ctl * tape->tape_block_size;
-       while (tape->stage_size > 0xffff) {
+       tape->buffer_size = *ctl * tape->blk_size;
+       while (tape->buffer_size > 0xffff) {
                printk(KERN_NOTICE "ide-tape: decreasing stage size\n");
                *ctl /= 2;
-               tape->stage_size = *ctl * tape->tape_block_size;
+               tape->buffer_size = *ctl * tape->blk_size;
        }
-       stage_size = tape->stage_size;
-       tape->pages_per_stage = stage_size / PAGE_SIZE;
-       if (stage_size % PAGE_SIZE) {
-               tape->pages_per_stage++;
-               tape->excess_bh_size = PAGE_SIZE - stage_size % PAGE_SIZE;
+       buffer_size = tape->buffer_size;
+       tape->pages_per_buffer = buffer_size / PAGE_SIZE;
+       if (buffer_size % PAGE_SIZE) {
+               tape->pages_per_buffer++;
+               tape->excess_bh_size = PAGE_SIZE - buffer_size % PAGE_SIZE;
        }
 
-       /* Select the "best" DSC read/write polling freq and pipeline size. */
+       /* select the "best" DSC read/write polling freq */
        speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]);
 
-       tape->max_stages = speed * 1000 * 10 / tape->stage_size;
-
-       /*
-        *      Limit memory use for pipeline to 10% of physical memory
-        */
-       si_meminfo(&si);
-       if (tape->max_stages * tape->stage_size > si.totalram * si.mem_unit / 10)
-               tape->max_stages = si.totalram * si.mem_unit / (10 * tape->stage_size);
-       tape->max_stages   = min(tape->max_stages, IDETAPE_MAX_PIPELINE_STAGES);
-       tape->min_pipeline = min(tape->max_stages, IDETAPE_MIN_PIPELINE_STAGES);
-       tape->max_pipeline = min(tape->max_stages * 2, IDETAPE_MAX_PIPELINE_STAGES);
-       if (tape->max_stages == 0)
-               tape->max_stages = tape->min_pipeline = tape->max_pipeline = 1;
-
-       t1 = (tape->stage_size * HZ) / (speed * 1000);
-       tmid = (*(u16 *)&tape->caps[16] * 32 * HZ) / (speed * 125);
-       tn = (IDETAPE_FIFO_THRESHOLD * tape->stage_size * HZ) / (speed * 1000);
-
-       if (tape->max_stages)
-               t = tn;
-       else
-               t = t1;
+       t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000);
 
        /*
-        *      Ensure that the number we got makes sense; limit
-        *      it within IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX.
+        * Ensure that the number we got makes sense; limit it within
+        * IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX.
         */
-       tape->best_dsc_rw_frequency = max_t(unsigned long, min_t(unsigned long, t, IDETAPE_DSC_RW_MAX), IDETAPE_DSC_RW_MIN);
+       tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN,
+                                        IDETAPE_DSC_RW_MAX);
        printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, "
-               "%dkB pipeline, %lums tDSC%s\n",
+               "%lums tDSC%s\n",
                drive->name, tape->name, *(u16 *)&tape->caps[14],
-               (*(u16 *)&tape->caps[16] * 512) / tape->stage_size,
-               tape->stage_size / 1024,
-               tape->max_stages * tape->stage_size / 1024,
-               tape->best_dsc_rw_frequency * 1000 / HZ,
-               drive->using_dma ? ", DMA":"");
+               (*(u16 *)&tape->caps[16] * 512) / tape->buffer_size,
+               tape->buffer_size / 1024,
+               tape->best_dsc_rw_freq * 1000 / HZ,
+               (drive->dev_flags & IDE_DFLAG_USING_DMA) ? ", DMA" : "");
 
-       idetape_add_settings(drive);
+       ide_proc_register_driver(drive, tape->driver);
 }
 
 static void ide_tape_remove(ide_drive_t *drive)
@@ -3921,24 +2256,27 @@ static void ide_tape_remove(ide_drive_t *drive)
        idetape_tape_t *tape = drive->driver_data;
 
        ide_proc_unregister_driver(drive, tape->driver);
-
+       device_del(&tape->dev);
        ide_unregister_region(tape->disk);
 
-       ide_tape_put(tape);
+       mutex_lock(&idetape_ref_mutex);
+       put_device(&tape->dev);
+       mutex_unlock(&idetape_ref_mutex);
 }
 
-static void ide_tape_release(struct kref *kref)
+static void ide_tape_release(struct device *dev)
 {
-       struct ide_tape_obj *tape = to_ide_tape(kref);
+       struct ide_tape_obj *tape = to_ide_drv(dev, ide_tape_obj);
        ide_drive_t *drive = tape->drive;
        struct gendisk *g = tape->disk;
 
-       BUG_ON(tape->first_stage != NULL || tape->merge_stage_size);
+       BUG_ON(tape->merge_bh_size);
 
-       drive->dsc_overlap = 0;
+       drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP;
        drive->driver_data = NULL;
        device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor));
-       device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor + 128));
+       device_destroy(idetape_sysfs_class,
+                       MKDEV(IDETAPE_MAJOR, tape->minor + 128));
        idetape_devs[tape->minor] = NULL;
        g->private_data = NULL;
        put_disk(g);
@@ -3963,11 +2301,21 @@ static ide_proc_entry_t idetape_proc[] = {
        { "name",       S_IFREG|S_IRUGO,        proc_idetape_read_name, NULL },
        { NULL, 0, NULL, NULL }
 };
+
+static ide_proc_entry_t *ide_tape_proc_entries(ide_drive_t *drive)
+{
+       return idetape_proc;
+}
+
+static const struct ide_proc_devset *ide_tape_proc_devsets(ide_drive_t *drive)
+{
+       return idetape_settings;
+}
 #endif
 
 static int ide_tape_probe(ide_drive_t *);
 
-static ide_driver_t idetape_driver = {
+static struct ide_driver idetape_driver = {
        .gen_driver = {
                .owner          = THIS_MODULE,
                .name           = "ide-tape",
@@ -3976,20 +2324,15 @@ static ide_driver_t idetape_driver = {
        .probe                  = ide_tape_probe,
        .remove                 = ide_tape_remove,
        .version                = IDETAPE_VERSION,
-       .media                  = ide_tape,
-       .supports_dsc_overlap   = 1,
        .do_request             = idetape_do_request,
        .end_request            = idetape_end_request,
-       .error                  = __ide_error,
-       .abort                  = __ide_abort,
 #ifdef CONFIG_IDE_PROC_FS
-       .proc                   = idetape_proc,
+       .proc_entries           = ide_tape_proc_entries,
+       .proc_devsets           = ide_tape_proc_devsets,
 #endif
 };
 
-/*
- *     Our character device supporting functions, passed to register_chrdev.
- */
+/* Our character device supporting functions, passed to register_chrdev. */
 static const struct file_operations idetape_fops = {
        .owner          = THIS_MODULE,
        .read           = idetape_chrdev_read,
@@ -3999,34 +2342,30 @@ static const struct file_operations idetape_fops = {
        .release        = idetape_chrdev_release,
 };
 
-static int idetape_open(struct inode *inode, struct file *filp)
+static int idetape_open(struct block_device *bdev, fmode_t mode)
 {
-       struct gendisk *disk = inode->i_bdev->bd_disk;
-       struct ide_tape_obj *tape;
+       struct ide_tape_obj *tape = ide_tape_get(bdev->bd_disk);
 
-       if (!(tape = ide_tape_get(disk)))
+       if (!tape)
                return -ENXIO;
 
        return 0;
 }
 
-static int idetape_release(struct inode *inode, struct file *filp)
+static int idetape_release(struct gendisk *disk, fmode_t mode)
 {
-       struct gendisk *disk = inode->i_bdev->bd_disk;
-       struct ide_tape_obj *tape = ide_tape_g(disk);
+       struct ide_tape_obj *tape = ide_drv_g(disk, ide_tape_obj);
 
        ide_tape_put(tape);
-
        return 0;
 }
 
-static int idetape_ioctl(struct inode *inode, struct file *file,
+static int idetape_ioctl(struct block_device *bdev, fmode_t mode,
                        unsigned int cmd, unsigned long arg)
 {
-       struct block_device *bdev = inode->i_bdev;
-       struct ide_tape_obj *tape = ide_tape_g(bdev->bd_disk);
+       struct ide_tape_obj *tape = ide_drv_g(bdev->bd_disk, ide_tape_obj);
        ide_drive_t *drive = tape->drive;
-       int err = generic_ide_ioctl(drive, file, bdev, cmd, arg);
+       int err = generic_ide_ioctl(drive, bdev, cmd, arg);
        if (err == -EINVAL)
                err = idetape_blkdev_ioctl(drive, cmd, arg);
        return err;
@@ -4036,7 +2375,7 @@ static struct block_device_operations idetape_block_ops = {
        .owner          = THIS_MODULE,
        .open           = idetape_open,
        .release        = idetape_release,
-       .ioctl          = idetape_ioctl,
+       .locked_ioctl   = idetape_ioctl,
 };
 
 static int ide_tape_probe(ide_drive_t *drive)
@@ -4047,25 +2386,20 @@ static int ide_tape_probe(ide_drive_t *drive)
 
        if (!strstr("ide-tape", drive->driver_req))
                goto failed;
-       if (!drive->present)
-               goto failed;
+
        if (drive->media != ide_tape)
                goto failed;
-       if (!idetape_identify_device (drive)) {
-               printk(KERN_ERR "ide-tape: %s: not supported by this version of ide-tape\n", drive->name);
-               goto failed;
-       }
-       if (drive->scsi) {
-               printk("ide-tape: passing drive %s to ide-scsi emulation.\n", drive->name);
+
+       if ((drive->dev_flags & IDE_DFLAG_ID_READ) &&
+           ide_check_atapi_device(drive, DRV_NAME) == 0) {
+               printk(KERN_ERR "ide-tape: %s: not supported by this version of"
+                               " the driver\n", drive->name);
                goto failed;
        }
-       if (strstr(drive->id->model, "OnStream DI-")) {
-               printk(KERN_WARNING "ide-tape: Use drive %s with ide-scsi emulation and osst.\n", drive->name);
-               printk(KERN_WARNING "ide-tape: OnStream support will be removed soon from ide-tape!\n");
-       }
-       tape = kzalloc(sizeof (idetape_tape_t), GFP_KERNEL);
+       tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL);
        if (tape == NULL) {
-               printk(KERN_ERR "ide-tape: %s: Can't allocate a tape structure\n", drive->name);
+               printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n",
+                               drive->name);
                goto failed;
        }
 
@@ -4075,9 +2409,12 @@ static int ide_tape_probe(ide_drive_t *drive)
 
        ide_init_disk(g, drive);
 
-       ide_proc_register_driver(drive, &idetape_driver);
+       tape->dev.parent = &drive->gendev;
+       tape->dev.release = ide_tape_release;
+       dev_set_name(&tape->dev, dev_name(&drive->gendev));
 
-       kref_init(&tape->kref);
+       if (device_register(&tape->dev))
+               goto out_free_disk;
 
        tape->drive = drive;
        tape->driver = &idetape_driver;
@@ -4096,25 +2433,25 @@ static int ide_tape_probe(ide_drive_t *drive)
        idetape_setup(drive, tape, minor);
 
        device_create(idetape_sysfs_class, &drive->gendev,
-                     MKDEV(IDETAPE_MAJOR, minor), "%s", tape->name);
+                     MKDEV(IDETAPE_MAJOR, minor), NULL, "%s", tape->name);
        device_create(idetape_sysfs_class, &drive->gendev,
-                       MKDEV(IDETAPE_MAJOR, minor + 128), "n%s", tape->name);
+                     MKDEV(IDETAPE_MAJOR, minor + 128), NULL,
+                     "n%s", tape->name);
 
        g->fops = &idetape_block_ops;
        ide_register_region(g);
 
        return 0;
 
+out_free_disk:
+       put_disk(g);
 out_free_tape:
        kfree(tape);
 failed:
        return -ENODEV;
 }
 
-MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver");
-MODULE_LICENSE("GPL");
-
-static void __exit idetape_exit (void)
+static void __exit idetape_exit(void)
 {
        driver_unregister(&idetape_driver.gen_driver);
        class_destroy(idetape_sysfs_class);
@@ -4133,7 +2470,8 @@ static int __init idetape_init(void)
        }
 
        if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) {
-               printk(KERN_ERR "ide-tape: Failed to register character device interface\n");
+               printk(KERN_ERR "ide-tape: Failed to register chrdev"
+                               " interface\n");
                error = -EBUSY;
                goto out_free_class;
        }
@@ -4156,3 +2494,5 @@ MODULE_ALIAS("ide:*m-tape*");
 module_init(idetape_init);
 module_exit(idetape_exit);
 MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR);
+MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver");
+MODULE_LICENSE("GPL");