UBI: fix multiple spelling typos
[safe/jmp/linux-2.6] / drivers / firewire / fw-sbp2.c
index d2fbfc6..2bcf515 100644 (file)
  * and many others.
  */
 
+#include <linux/blkdev.h>
+#include <linux/bug.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
 #include <linux/kernel.h>
+#include <linux/mod_devicetable.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
-#include <linux/mod_devicetable.h>
-#include <linux/device.h>
 #include <linux/scatterlist.h>
-#include <linux/dma-mapping.h>
-#include <linux/blkdev.h>
 #include <linux/string.h>
 #include <linux/stringify.h>
 #include <linux/timer.h>
 #include <linux/workqueue.h>
+#include <asm/system.h>
 
 #include <scsi/scsi.h>
 #include <scsi/scsi_cmnd.h>
 #include <scsi/scsi_device.h>
 #include <scsi/scsi_host.h>
 
-#include "fw-transaction.h"
-#include "fw-topology.h"
 #include "fw-device.h"
+#include "fw-topology.h"
+#include "fw-transaction.h"
 
 /*
  * So far only bridges from Oxford Semiconductor are known to support
@@ -81,6 +84,14 @@ MODULE_PARM_DESC(exclusive_login, "Exclusive login to sbp2 device "
  *   Avoids access beyond actual disk limits on devices with an off-by-one bug.
  *   Don't use this with devices which don't have this bug.
  *
+ * - delay inquiry
+ *   Wait extra SBP2_INQUIRY_DELAY seconds after login before SCSI inquiry.
+ *
+ * - power condition
+ *   Set the power condition field in the START STOP UNIT commands sent by
+ *   sd_mod on suspend, resume, and shutdown (if manage_start_stop is on).
+ *   Some disks need this to spin down or to resume properly.
+ *
  * - override internal blacklist
  *   Instead of adding to the built-in blacklist, use only the workarounds
  *   specified in the module load parameter.
@@ -90,6 +101,9 @@ MODULE_PARM_DESC(exclusive_login, "Exclusive login to sbp2 device "
 #define SBP2_WORKAROUND_INQUIRY_36     0x2
 #define SBP2_WORKAROUND_MODE_SENSE_8   0x4
 #define SBP2_WORKAROUND_FIX_CAPACITY   0x8
+#define SBP2_WORKAROUND_DELAY_INQUIRY  0x10
+#define SBP2_INQUIRY_DELAY             12
+#define SBP2_WORKAROUND_POWER_CONDITION        0x20
 #define SBP2_WORKAROUND_OVERRIDE       0x100
 
 static int sbp2_param_workarounds;
@@ -99,6 +113,9 @@ MODULE_PARM_DESC(workarounds, "Work around device bugs (default = 0"
        ", 36 byte inquiry = "    __stringify(SBP2_WORKAROUND_INQUIRY_36)
        ", skip mode page 8 = "   __stringify(SBP2_WORKAROUND_MODE_SENSE_8)
        ", fix capacity = "       __stringify(SBP2_WORKAROUND_FIX_CAPACITY)
+       ", delay inquiry = "      __stringify(SBP2_WORKAROUND_DELAY_INQUIRY)
+       ", set power condition in start stop unit = "
+                                 __stringify(SBP2_WORKAROUND_POWER_CONDITION)
        ", override internal blacklist = " __stringify(SBP2_WORKAROUND_OVERRIDE)
        ", or a combination)");
 
@@ -114,7 +131,6 @@ static const char sbp2_driver_name[] = "sbp2";
 struct sbp2_logical_unit {
        struct sbp2_target *tgt;
        struct list_head link;
-       struct scsi_device *sdev;
        struct fw_address_handler address_handler;
        struct list_head orb_list;
 
@@ -131,6 +147,8 @@ struct sbp2_logical_unit {
        int generation;
        int retries;
        struct delayed_work work;
+       bool has_sdev;
+       bool blocked;
 };
 
 /*
@@ -140,24 +158,46 @@ struct sbp2_logical_unit {
 struct sbp2_target {
        struct kref kref;
        struct fw_unit *unit;
+       const char *bus_id;
+       struct list_head lu_list;
 
        u64 management_agent_address;
+       u64 guid;
        int directory_id;
        int node_id;
        int address_high;
+       unsigned int workarounds;
+       unsigned int mgt_orb_timeout;
+       unsigned int max_payload;
 
-       unsigned workarounds;
-       struct list_head lu_list;
+       int dont_block; /* counter for each logical unit */
+       int blocked;    /* ditto */
 };
 
-#define SBP2_MAX_SG_ELEMENT_LENGTH     0xf000
-#define SBP2_ORB_TIMEOUT               2000    /* Timeout in ms */
+/* Impossible login_id, to detect logout attempt before successful login */
+#define INVALID_LOGIN_ID 0x10000
+
+/*
+ * Per section 7.4.8 of the SBP-2 spec, a mgt_ORB_timeout value can be
+ * provided in the config rom. Most devices do provide a value, which
+ * we'll use for login management orbs, but with some sane limits.
+ */
+#define SBP2_MIN_LOGIN_ORB_TIMEOUT     5000U   /* Timeout in ms */
+#define SBP2_MAX_LOGIN_ORB_TIMEOUT     40000U  /* Timeout in ms */
+#define SBP2_ORB_TIMEOUT               2000U   /* Timeout in ms */
 #define SBP2_ORB_NULL                  0x80000000
+#define SBP2_RETRY_LIMIT               0xf             /* 15 retries */
+#define SBP2_CYCLE_LIMIT               (0xc8 << 12)    /* 200 125us cycles */
 
-#define SBP2_DIRECTION_TO_MEDIA                0x0
-#define SBP2_DIRECTION_FROM_MEDIA      0x1
+/*
+ * The default maximum s/g segment size of a FireWire controller is
+ * usually 0x10000, but SBP-2 only allows 0xffff. Since buffers have to
+ * be quadlet-aligned, we set the length limit to 0xffff & ~3.
+ */
+#define SBP2_MAX_SEG_SIZE              0xfffc
 
 /* Unit directory keys */
+#define SBP2_CSR_UNIT_CHARACTERISTICS  0x3a
 #define SBP2_CSR_FIRMWARE_REVISION     0x3c
 #define SBP2_CSR_LOGICAL_UNIT_NUMBER   0x14
 #define SBP2_CSR_LOGICAL_UNIT_DIRECTORY        0xd4
@@ -202,8 +242,8 @@ struct sbp2_status {
 };
 
 struct sbp2_pointer {
-       u32 high;
-       u32 low;
+       __be32 high;
+       __be32 low;
 };
 
 struct sbp2_orb {
@@ -231,8 +271,8 @@ struct sbp2_management_orb {
        struct {
                struct sbp2_pointer password;
                struct sbp2_pointer response;
-               u32 misc;
-               u32 length;
+               __be32 misc;
+               __be32 length;
                struct sbp2_pointer status_fifo;
        } request;
        __be32 response[4];
@@ -241,20 +281,17 @@ struct sbp2_management_orb {
        struct sbp2_status status;
 };
 
-#define LOGIN_RESPONSE_GET_LOGIN_ID(v) ((v).misc & 0xffff)
-#define LOGIN_RESPONSE_GET_LENGTH(v)   (((v).misc >> 16) & 0xffff)
-
 struct sbp2_login_response {
-       u32 misc;
+       __be32 misc;
        struct sbp2_pointer command_block_agent;
-       u32 reconnect_hold;
+       __be32 reconnect_hold;
 };
 #define COMMAND_ORB_DATA_SIZE(v)       ((v))
 #define COMMAND_ORB_PAGE_SIZE(v)       ((v) << 16)
 #define COMMAND_ORB_PAGE_TABLE_PRESENT ((1) << 19)
 #define COMMAND_ORB_MAX_PAYLOAD(v)     ((v) << 20)
 #define COMMAND_ORB_SPEED(v)           ((v) << 24)
-#define COMMAND_ORB_DIRECTION(v)       ((v) << 27)
+#define COMMAND_ORB_DIRECTION          ((1) << 27)
 #define COMMAND_ORB_REQUEST_FORMAT(v)  ((v) << 29)
 #define COMMAND_ORB_NOTIFY             ((1) << 31)
 
@@ -263,7 +300,7 @@ struct sbp2_command_orb {
        struct {
                struct sbp2_pointer next;
                struct sbp2_pointer data_descriptor;
-               u32 misc;
+               __be32 misc;
                u8 command_block[12];
        } request;
        struct scsi_cmnd *cmd;
@@ -274,51 +311,77 @@ struct sbp2_command_orb {
        dma_addr_t page_table_bus;
 };
 
+#define SBP2_ROM_VALUE_WILDCARD ~0         /* match all */
+#define SBP2_ROM_VALUE_MISSING  0xff000000 /* not present in the unit dir. */
+
 /*
  * List of devices with known bugs.
  *
  * The firmware_revision field, masked with 0xffff00, is the best
  * indicator for the type of bridge chip of a device.  It yields a few
  * false positives but this did not break correctly behaving devices
- * so far.  We use ~0 as a wildcard, since the 24 bit values we get
- * from the config rom can never match that.
+ * so far.
  */
 static const struct {
        u32 firmware_revision;
        u32 model;
-       unsigned workarounds;
+       unsigned int workarounds;
 } sbp2_workarounds_table[] = {
        /* DViCO Momobay CX-1 with TSB42AA9 bridge */ {
                .firmware_revision      = 0x002800,
                .model                  = 0x001010,
                .workarounds            = SBP2_WORKAROUND_INQUIRY_36 |
-                                         SBP2_WORKAROUND_MODE_SENSE_8,
+                                         SBP2_WORKAROUND_MODE_SENSE_8 |
+                                         SBP2_WORKAROUND_POWER_CONDITION,
+       },
+       /* DViCO Momobay FX-3A with TSB42AA9A bridge */ {
+               .firmware_revision      = 0x002800,
+               .model                  = 0x000000,
+               .workarounds            = SBP2_WORKAROUND_DELAY_INQUIRY |
+                                         SBP2_WORKAROUND_POWER_CONDITION,
        },
        /* Initio bridges, actually only needed for some older ones */ {
                .firmware_revision      = 0x000200,
-               .model                  = ~0,
+               .model                  = SBP2_ROM_VALUE_WILDCARD,
                .workarounds            = SBP2_WORKAROUND_INQUIRY_36,
        },
+       /* PL-3507 bridge with Prolific firmware */ {
+               .firmware_revision      = 0x012800,
+               .model                  = SBP2_ROM_VALUE_WILDCARD,
+               .workarounds            = SBP2_WORKAROUND_POWER_CONDITION,
+       },
        /* Symbios bridge */ {
                .firmware_revision      = 0xa0b800,
-               .model                  = ~0,
+               .model                  = SBP2_ROM_VALUE_WILDCARD,
+               .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
+       },
+       /* Datafab MD2-FW2 with Symbios/LSILogic SYM13FW500 bridge */ {
+               .firmware_revision      = 0x002600,
+               .model                  = SBP2_ROM_VALUE_WILDCARD,
                .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
        },
-
        /*
-        * There are iPods (2nd gen, 3rd gen) with model_id == 0, but
-        * these iPods do not feature the read_capacity bug according
-        * to one report.  Read_capacity behaviour as well as model_id
-        * could change due to Apple-supplied firmware updates though.
+        * iPod 2nd generation: needs 128k max transfer size workaround
+        * iPod 3rd generation: needs fix capacity workaround
         */
-
-       /* iPod 4th generation. */ {
+       {
+               .firmware_revision      = 0x0a2700,
+               .model                  = 0x000000,
+               .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS |
+                                         SBP2_WORKAROUND_FIX_CAPACITY,
+       },
+       /* iPod 4th generation */ {
                .firmware_revision      = 0x0a2700,
                .model                  = 0x000021,
                .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
        },
        /* iPod mini */ {
                .firmware_revision      = 0x0a2700,
+               .model                  = 0x000022,
+               .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
+       },
+       /* iPod mini */ {
+               .firmware_revision      = 0x0a2700,
                .model                  = 0x000023,
                .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
        },
@@ -329,20 +392,18 @@ static const struct {
        }
 };
 
-static void
-free_orb(struct kref *kref)
+static void free_orb(struct kref *kref)
 {
        struct sbp2_orb *orb = container_of(kref, struct sbp2_orb, kref);
 
        kfree(orb);
 }
 
-static void
-sbp2_status_write(struct fw_card *card, struct fw_request *request,
-                 int tcode, int destination, int source,
-                 int generation, int speed,
-                 unsigned long long offset,
-                 void *payload, size_t length, void *callback_data)
+static void sbp2_status_write(struct fw_card *card, struct fw_request *request,
+                             int tcode, int destination, int source,
+                             int generation, int speed,
+                             unsigned long long offset,
+                             void *payload, size_t length, void *callback_data)
 {
        struct sbp2_logical_unit *lu = callback_data;
        struct sbp2_orb *orb;
@@ -388,9 +449,8 @@ sbp2_status_write(struct fw_card *card, struct fw_request *request,
        fw_send_response(card, request, RCODE_COMPLETE);
 }
 
-static void
-complete_transaction(struct fw_card *card, int rcode,
-                    void *payload, size_t length, void *data)
+static void complete_transaction(struct fw_card *card, int rcode,
+                                void *payload, size_t length, void *data)
 {
        struct sbp2_orb *orb = data;
        unsigned long flags;
@@ -419,16 +479,14 @@ complete_transaction(struct fw_card *card, int rcode,
        kref_put(&orb->kref, free_orb);
 }
 
-static void
-sbp2_send_orb(struct sbp2_orb *orb, struct sbp2_logical_unit *lu,
-             int node_id, int generation, u64 offset)
+static void sbp2_send_orb(struct sbp2_orb *orb, struct sbp2_logical_unit *lu,
+                         int node_id, int generation, u64 offset)
 {
        struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
        unsigned long flags;
 
        orb->pointer.high = 0;
-       orb->pointer.low = orb->request_bus;
-       fw_memcpy_to_be32(&orb->pointer, &orb->pointer, sizeof(orb->pointer));
+       orb->pointer.low = cpu_to_be32(orb->request_bus);
 
        spin_lock_irqsave(&device->card->lock, flags);
        list_add_tail(&orb->link, &lu->orb_list);
@@ -469,8 +527,8 @@ static int sbp2_cancel_orbs(struct sbp2_logical_unit *lu)
        return retval;
 }
 
-static void
-complete_management_orb(struct sbp2_orb *base_orb, struct sbp2_status *status)
+static void complete_management_orb(struct sbp2_orb *base_orb,
+                                   struct sbp2_status *status)
 {
        struct sbp2_management_orb *orb =
                container_of(base_orb, struct sbp2_management_orb, base);
@@ -480,15 +538,18 @@ complete_management_orb(struct sbp2_orb *base_orb, struct sbp2_status *status)
        complete(&orb->done);
 }
 
-static int
-sbp2_send_management_orb(struct sbp2_logical_unit *lu, int node_id,
-                        int generation, int function, int lun_or_login_id,
-                        void *response)
+static int sbp2_send_management_orb(struct sbp2_logical_unit *lu, int node_id,
+                                   int generation, int function,
+                                   int lun_or_login_id, void *response)
 {
        struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
        struct sbp2_management_orb *orb;
+       unsigned int timeout;
        int retval = -ENOMEM;
 
+       if (function == SBP2_LOGOUT_REQUEST && fw_device_is_shutdown(device))
+               return 0;
+
        orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
        if (orb == NULL)
                return -ENOMEM;
@@ -497,62 +558,64 @@ sbp2_send_management_orb(struct sbp2_logical_unit *lu, int node_id,
        orb->response_bus =
                dma_map_single(device->card->device, &orb->response,
                               sizeof(orb->response), DMA_FROM_DEVICE);
-       if (dma_mapping_error(orb->response_bus))
+       if (dma_mapping_error(device->card->device, orb->response_bus))
                goto fail_mapping_response;
 
-       orb->request.response.high    = 0;
-       orb->request.response.low     = orb->response_bus;
+       orb->request.response.high = 0;
+       orb->request.response.low  = cpu_to_be32(orb->response_bus);
 
-       orb->request.misc =
+       orb->request.misc = cpu_to_be32(
                MANAGEMENT_ORB_NOTIFY |
                MANAGEMENT_ORB_FUNCTION(function) |
-               MANAGEMENT_ORB_LUN(lun_or_login_id);
-       orb->request.length =
-               MANAGEMENT_ORB_RESPONSE_LENGTH(sizeof(orb->response));
+               MANAGEMENT_ORB_LUN(lun_or_login_id));
+       orb->request.length = cpu_to_be32(
+               MANAGEMENT_ORB_RESPONSE_LENGTH(sizeof(orb->response)));
 
-       orb->request.status_fifo.high = lu->address_handler.offset >> 32;
-       orb->request.status_fifo.low  = lu->address_handler.offset;
+       orb->request.status_fifo.high =
+               cpu_to_be32(lu->address_handler.offset >> 32);
+       orb->request.status_fifo.low  =
+               cpu_to_be32(lu->address_handler.offset);
 
        if (function == SBP2_LOGIN_REQUEST) {
                /* Ask for 2^2 == 4 seconds reconnect grace period */
-               orb->request.misc |=
+               orb->request.misc |= cpu_to_be32(
                        MANAGEMENT_ORB_RECONNECT(2) |
-                       MANAGEMENT_ORB_EXCLUSIVE(sbp2_param_exclusive_login);
+                       MANAGEMENT_ORB_EXCLUSIVE(sbp2_param_exclusive_login));
+               timeout = lu->tgt->mgt_orb_timeout;
+       } else {
+               timeout = SBP2_ORB_TIMEOUT;
        }
 
-       fw_memcpy_to_be32(&orb->request, &orb->request, sizeof(orb->request));
-
        init_completion(&orb->done);
        orb->base.callback = complete_management_orb;
 
        orb->base.request_bus =
                dma_map_single(device->card->device, &orb->request,
                               sizeof(orb->request), DMA_TO_DEVICE);
-       if (dma_mapping_error(orb->base.request_bus))
+       if (dma_mapping_error(device->card->device, orb->base.request_bus))
                goto fail_mapping_request;
 
        sbp2_send_orb(&orb->base, lu, node_id, generation,
                      lu->tgt->management_agent_address);
 
-       wait_for_completion_timeout(&orb->done,
-                                   msecs_to_jiffies(SBP2_ORB_TIMEOUT));
+       wait_for_completion_timeout(&orb->done, msecs_to_jiffies(timeout));
 
        retval = -EIO;
        if (sbp2_cancel_orbs(lu) == 0) {
-               fw_error("orb reply timed out, rcode=0x%02x\n",
-                        orb->base.rcode);
+               fw_error("%s: orb reply timed out, rcode=0x%02x\n",
+                        lu->tgt->bus_id, orb->base.rcode);
                goto out;
        }
 
        if (orb->base.rcode != RCODE_COMPLETE) {
-               fw_error("management write failed, rcode 0x%02x\n",
-                        orb->base.rcode);
+               fw_error("%s: management write failed, rcode 0x%02x\n",
+                        lu->tgt->bus_id, orb->base.rcode);
                goto out;
        }
 
        if (STATUS_GET_RESPONSE(orb->status) != 0 ||
            STATUS_GET_SBP_STATUS(orb->status) != 0) {
-               fw_error("error status: %d:%d\n",
+               fw_error("%s: error status: %d:%d\n", lu->tgt->bus_id,
                         STATUS_GET_RESPONSE(orb->status),
                         STATUS_GET_SBP_STATUS(orb->status));
                goto out;
@@ -567,38 +630,140 @@ sbp2_send_management_orb(struct sbp2_logical_unit *lu, int node_id,
                         sizeof(orb->response), DMA_FROM_DEVICE);
  fail_mapping_response:
        if (response)
-               fw_memcpy_from_be32(response,
-                                   orb->response, sizeof(orb->response));
+               memcpy(response, orb->response, sizeof(orb->response));
        kref_put(&orb->base.kref, free_orb);
 
        return retval;
 }
 
-static void
-complete_agent_reset_write(struct fw_card *card, int rcode,
-                          void *payload, size_t length, void *data)
+static void sbp2_agent_reset(struct sbp2_logical_unit *lu)
 {
-       struct fw_transaction *t = data;
+       struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
+       __be32 d = 0;
+
+       fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
+                          lu->tgt->node_id, lu->generation, device->max_speed,
+                          lu->command_block_agent_address + SBP2_AGENT_RESET,
+                          &d, sizeof(d));
+}
 
-       kfree(t);
+static void complete_agent_reset_write_no_wait(struct fw_card *card,
+               int rcode, void *payload, size_t length, void *data)
+{
+       kfree(data);
 }
 
-static int sbp2_agent_reset(struct sbp2_logical_unit *lu)
+static void sbp2_agent_reset_no_wait(struct sbp2_logical_unit *lu)
 {
        struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
        struct fw_transaction *t;
-       static u32 zero;
+       static __be32 d;
 
-       t = kzalloc(sizeof(*t), GFP_ATOMIC);
+       t = kmalloc(sizeof(*t), GFP_ATOMIC);
        if (t == NULL)
-               return -ENOMEM;
+               return;
 
        fw_send_request(device->card, t, TCODE_WRITE_QUADLET_REQUEST,
                        lu->tgt->node_id, lu->generation, device->max_speed,
                        lu->command_block_agent_address + SBP2_AGENT_RESET,
-                       &zero, sizeof(zero), complete_agent_reset_write, t);
+                       &d, sizeof(d), complete_agent_reset_write_no_wait, t);
+}
 
-       return 0;
+static inline void sbp2_allow_block(struct sbp2_logical_unit *lu)
+{
+       /*
+        * We may access dont_block without taking card->lock here:
+        * All callers of sbp2_allow_block() and all callers of sbp2_unblock()
+        * are currently serialized against each other.
+        * And a wrong result in sbp2_conditionally_block()'s access of
+        * dont_block is rather harmless, it simply misses its first chance.
+        */
+       --lu->tgt->dont_block;
+}
+
+/*
+ * Blocks lu->tgt if all of the following conditions are met:
+ *   - Login, INQUIRY, and high-level SCSI setup of all of the target's
+ *     logical units have been finished (indicated by dont_block == 0).
+ *   - lu->generation is stale.
+ *
+ * Note, scsi_block_requests() must be called while holding card->lock,
+ * otherwise it might foil sbp2_[conditionally_]unblock()'s attempt to
+ * unblock the target.
+ */
+static void sbp2_conditionally_block(struct sbp2_logical_unit *lu)
+{
+       struct sbp2_target *tgt = lu->tgt;
+       struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
+       struct Scsi_Host *shost =
+               container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
+       unsigned long flags;
+
+       spin_lock_irqsave(&card->lock, flags);
+       if (!tgt->dont_block && !lu->blocked &&
+           lu->generation != card->generation) {
+               lu->blocked = true;
+               if (++tgt->blocked == 1)
+                       scsi_block_requests(shost);
+       }
+       spin_unlock_irqrestore(&card->lock, flags);
+}
+
+/*
+ * Unblocks lu->tgt as soon as all its logical units can be unblocked.
+ * Note, it is harmless to run scsi_unblock_requests() outside the
+ * card->lock protected section.  On the other hand, running it inside
+ * the section might clash with shost->host_lock.
+ */
+static void sbp2_conditionally_unblock(struct sbp2_logical_unit *lu)
+{
+       struct sbp2_target *tgt = lu->tgt;
+       struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
+       struct Scsi_Host *shost =
+               container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
+       unsigned long flags;
+       bool unblock = false;
+
+       spin_lock_irqsave(&card->lock, flags);
+       if (lu->blocked && lu->generation == card->generation) {
+               lu->blocked = false;
+               unblock = --tgt->blocked == 0;
+       }
+       spin_unlock_irqrestore(&card->lock, flags);
+
+       if (unblock)
+               scsi_unblock_requests(shost);
+}
+
+/*
+ * Prevents future blocking of tgt and unblocks it.
+ * Note, it is harmless to run scsi_unblock_requests() outside the
+ * card->lock protected section.  On the other hand, running it inside
+ * the section might clash with shost->host_lock.
+ */
+static void sbp2_unblock(struct sbp2_target *tgt)
+{
+       struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
+       struct Scsi_Host *shost =
+               container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
+       unsigned long flags;
+
+       spin_lock_irqsave(&card->lock, flags);
+       ++tgt->dont_block;
+       spin_unlock_irqrestore(&card->lock, flags);
+
+       scsi_unblock_requests(shost);
+}
+
+static int sbp2_lun2int(u16 lun)
+{
+       struct scsi_lun eight_bytes_lun;
+
+       memset(&eight_bytes_lun, 0, sizeof(eight_bytes_lun));
+       eight_bytes_lun.scsi_lun[0] = (lun >> 8) & 0xff;
+       eight_bytes_lun.scsi_lun[1] = lun & 0xff;
+
+       return scsilun_to_int(&eight_bytes_lun);
 }
 
 static void sbp2_release_target(struct kref *kref)
@@ -607,43 +772,87 @@ static void sbp2_release_target(struct kref *kref)
        struct sbp2_logical_unit *lu, *next;
        struct Scsi_Host *shost =
                container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
+       struct scsi_device *sdev;
        struct fw_device *device = fw_device(tgt->unit->device.parent);
 
-       list_for_each_entry_safe(lu, next, &tgt->lu_list, link) {
-               if (lu->sdev)
-                       scsi_remove_device(lu->sdev);
-
-               if (!fw_device_is_shutdown(device))
-                       sbp2_send_management_orb(lu, tgt->node_id,
-                                       lu->generation, SBP2_LOGOUT_REQUEST,
-                                       lu->login_id, NULL);
+       /* prevent deadlocks */
+       sbp2_unblock(tgt);
 
+       list_for_each_entry_safe(lu, next, &tgt->lu_list, link) {
+               sdev = scsi_device_lookup(shost, 0, 0, sbp2_lun2int(lu->lun));
+               if (sdev) {
+                       scsi_remove_device(sdev);
+                       scsi_device_put(sdev);
+               }
+               if (lu->login_id != INVALID_LOGIN_ID) {
+                       int generation, node_id;
+                       /*
+                        * tgt->node_id may be obsolete here if we failed
+                        * during initial login or after a bus reset where
+                        * the topology changed.
+                        */
+                       generation = device->generation;
+                       smp_rmb(); /* node_id vs. generation */
+                       node_id    = device->node_id;
+                       sbp2_send_management_orb(lu, node_id, generation,
+                                                SBP2_LOGOUT_REQUEST,
+                                                lu->login_id, NULL);
+               }
                fw_core_remove_address_handler(&lu->address_handler);
                list_del(&lu->link);
                kfree(lu);
        }
        scsi_remove_host(shost);
-       fw_notify("released %s\n", tgt->unit->device.bus_id);
+       fw_notify("released %s, target %d:0:0\n", tgt->bus_id, shost->host_no);
 
-       put_device(&tgt->unit->device);
+       fw_unit_put(tgt->unit);
        scsi_host_put(shost);
+       fw_device_put(device);
 }
 
 static struct workqueue_struct *sbp2_wq;
 
+static void sbp2_target_put(struct sbp2_target *tgt)
+{
+       kref_put(&tgt->kref, sbp2_release_target);
+}
+
 /*
  * Always get the target's kref when scheduling work on one its units.
  * Each workqueue job is responsible to call sbp2_target_put() upon return.
  */
 static void sbp2_queue_work(struct sbp2_logical_unit *lu, unsigned long delay)
 {
-       if (queue_delayed_work(sbp2_wq, &lu->work, delay))
-               kref_get(&lu->tgt->kref);
+       kref_get(&lu->tgt->kref);
+       if (!queue_delayed_work(sbp2_wq, &lu->work, delay))
+               sbp2_target_put(lu->tgt);
 }
 
-static void sbp2_target_put(struct sbp2_target *tgt)
+/*
+ * Write retransmit retry values into the BUSY_TIMEOUT register.
+ * - The single-phase retry protocol is supported by all SBP-2 devices, but the
+ *   default retry_limit value is 0 (i.e. never retry transmission). We write a
+ *   saner value after logging into the device.
+ * - The dual-phase retry protocol is optional to implement, and if not
+ *   supported, writes to the dual-phase portion of the register will be
+ *   ignored. We try to write the original 1394-1995 default here.
+ * - In the case of devices that are also SBP-3-compliant, all writes are
+ *   ignored, as the register is read-only, but contains single-phase retry of
+ *   15, which is what we're trying to set for all SBP-2 device anyway, so this
+ *   write attempt is safe and yields more consistent behavior for all devices.
+ *
+ * See section 8.3.2.3.5 of the 1394-1995 spec, section 6.2 of the SBP-2 spec,
+ * and section 6.4 of the SBP-3 spec for further details.
+ */
+static void sbp2_set_busy_timeout(struct sbp2_logical_unit *lu)
 {
-       kref_put(&tgt->kref, sbp2_release_target);
+       struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
+       __be32 d = cpu_to_be32(SBP2_CYCLE_LIMIT | SBP2_RETRY_LIMIT);
+
+       fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
+                          lu->tgt->node_id, lu->generation, device->max_speed,
+                          CSR_REGISTER_BASE + CSR_BUSY_TIMEOUT,
+                          &d, sizeof(d));
 }
 
 static void sbp2_reconnect(struct work_struct *work);
@@ -652,70 +861,110 @@ static void sbp2_login(struct work_struct *work)
 {
        struct sbp2_logical_unit *lu =
                container_of(work, struct sbp2_logical_unit, work.work);
-       struct Scsi_Host *shost =
-               container_of((void *)lu->tgt, struct Scsi_Host, hostdata[0]);
+       struct sbp2_target *tgt = lu->tgt;
+       struct fw_device *device = fw_device(tgt->unit->device.parent);
+       struct Scsi_Host *shost;
        struct scsi_device *sdev;
-       struct scsi_lun eight_bytes_lun;
-       struct fw_unit *unit = lu->tgt->unit;
-       struct fw_device *device = fw_device(unit->device.parent);
        struct sbp2_login_response response;
        int generation, node_id, local_node_id;
 
-       generation    = device->card->generation;
-       node_id       = device->node->node_id;
-       local_node_id = device->card->local_node->node_id;
+       if (fw_device_is_shutdown(device))
+               goto out;
+
+       generation    = device->generation;
+       smp_rmb();    /* node IDs must not be older than generation */
+       node_id       = device->node_id;
+       local_node_id = device->card->node_id;
+
+       /* If this is a re-login attempt, log out, or we might be rejected. */
+       if (lu->has_sdev)
+               sbp2_send_management_orb(lu, device->node_id, generation,
+                               SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 
        if (sbp2_send_management_orb(lu, node_id, generation,
                                SBP2_LOGIN_REQUEST, lu->lun, &response) < 0) {
-               if (lu->retries++ < 5)
+               if (lu->retries++ < 5) {
                        sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
-               else
-                       fw_error("failed to login to %s LUN %04x\n",
-                                unit->device.bus_id, lu->lun);
+               } else {
+                       fw_error("%s: failed to login to LUN %04x\n",
+                                tgt->bus_id, lu->lun);
+                       /* Let any waiting I/O fail from now on. */
+                       sbp2_unblock(lu->tgt);
+               }
                goto out;
        }
 
-       lu->generation        = generation;
-       lu->tgt->node_id      = node_id;
-       lu->tgt->address_high = local_node_id << 16;
+       tgt->node_id      = node_id;
+       tgt->address_high = local_node_id << 16;
+       smp_wmb();        /* node IDs must not be older than generation */
+       lu->generation    = generation;
 
-       /* Get command block agent offset and login id. */
        lu->command_block_agent_address =
-               ((u64) (response.command_block_agent.high & 0xffff) << 32) |
-               response.command_block_agent.low;
-       lu->login_id = LOGIN_RESPONSE_GET_LOGIN_ID(response);
+               ((u64)(be32_to_cpu(response.command_block_agent.high) & 0xffff)
+                     << 32) | be32_to_cpu(response.command_block_agent.low);
+       lu->login_id = be32_to_cpu(response.misc) & 0xffff;
 
-       fw_notify("logged in to %s LUN %04x (%d retries)\n",
-                 unit->device.bus_id, lu->lun, lu->retries);
+       fw_notify("%s: logged in to LUN %04x (%d retries)\n",
+                 tgt->bus_id, lu->lun, lu->retries);
 
-#if 0
-       /* FIXME: The linux1394 sbp2 does this last step. */
-       sbp2_set_busy_timeout(scsi_id);
-#endif
+       /* set appropriate retry limit(s) in BUSY_TIMEOUT register */
+       sbp2_set_busy_timeout(lu);
 
        PREPARE_DELAYED_WORK(&lu->work, sbp2_reconnect);
        sbp2_agent_reset(lu);
 
-       memset(&eight_bytes_lun, 0, sizeof(eight_bytes_lun));
-       eight_bytes_lun.scsi_lun[0] = (lu->lun >> 8) & 0xff;
-       eight_bytes_lun.scsi_lun[1] = lu->lun & 0xff;
+       /* This was a re-login. */
+       if (lu->has_sdev) {
+               sbp2_cancel_orbs(lu);
+               sbp2_conditionally_unblock(lu);
+               goto out;
+       }
 
-       sdev = __scsi_add_device(shost, 0, 0,
-                                scsilun_to_int(&eight_bytes_lun), lu);
-       if (IS_ERR(sdev)) {
-               sbp2_send_management_orb(lu, node_id, generation,
-                               SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
-               /*
-                * Set this back to sbp2_login so we fall back and
-                * retry login on bus reset.
-                */
-               PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
-       } else {
-               lu->sdev = sdev;
+       if (lu->tgt->workarounds & SBP2_WORKAROUND_DELAY_INQUIRY)
+               ssleep(SBP2_INQUIRY_DELAY);
+
+       shost = container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
+       sdev = __scsi_add_device(shost, 0, 0, sbp2_lun2int(lu->lun), lu);
+       /*
+        * FIXME:  We are unable to perform reconnects while in sbp2_login().
+        * Therefore __scsi_add_device() will get into trouble if a bus reset
+        * happens in parallel.  It will either fail or leave us with an
+        * unusable sdev.  As a workaround we check for this and retry the
+        * whole login and SCSI probing.
+        */
+
+       /* Reported error during __scsi_add_device() */
+       if (IS_ERR(sdev))
+               goto out_logout_login;
+
+       /* Unreported error during __scsi_add_device() */
+       smp_rmb(); /* get current card generation */
+       if (generation != device->card->generation) {
+               scsi_remove_device(sdev);
                scsi_device_put(sdev);
+               goto out_logout_login;
        }
+
+       /* No error during __scsi_add_device() */
+       lu->has_sdev = true;
+       scsi_device_put(sdev);
+       sbp2_allow_block(lu);
+       goto out;
+
+ out_logout_login:
+       smp_rmb(); /* generation may have changed */
+       generation = device->generation;
+       smp_rmb(); /* node_id must not be older than generation */
+
+       sbp2_send_management_orb(lu, device->node_id, generation,
+                                SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
+       /*
+        * If a bus reset happened, sbp2_update will have requeued
+        * lu->work already.  Reset the work from reconnect to login.
+        */
+       PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
  out:
-       sbp2_target_put(lu->tgt);
+       sbp2_target_put(tgt);
 }
 
 static int sbp2_add_logical_unit(struct sbp2_target *tgt, int lun_entry)
@@ -736,10 +985,13 @@ static int sbp2_add_logical_unit(struct sbp2_target *tgt, int lun_entry)
                return -ENOMEM;
        }
 
-       lu->tgt  = tgt;
-       lu->sdev = NULL;
-       lu->lun  = lun_entry & 0xffff;
-       lu->retries = 0;
+       lu->tgt      = tgt;
+       lu->lun      = lun_entry & 0xffff;
+       lu->login_id = INVALID_LOGIN_ID;
+       lu->retries  = 0;
+       lu->has_sdev = false;
+       lu->blocked  = false;
+       ++tgt->dont_block;
        INIT_LIST_HEAD(&lu->orb_list);
        INIT_DELAYED_WORK(&lu->work, sbp2_login);
 
@@ -765,6 +1017,7 @@ static int sbp2_scan_unit_dir(struct sbp2_target *tgt, u32 *directory,
 {
        struct fw_csr_iterator ci;
        int key, value;
+       unsigned int timeout;
 
        fw_csr_iterator_init(&ci, directory);
        while (fw_csr_iterator_next(&ci, &key, &value)) {
@@ -787,13 +1040,29 @@ static int sbp2_scan_unit_dir(struct sbp2_target *tgt, u32 *directory,
                        *firmware_revision = value;
                        break;
 
+               case SBP2_CSR_UNIT_CHARACTERISTICS:
+                       /* the timeout value is stored in 500ms units */
+                       timeout = ((unsigned int) value >> 8 & 0xff) * 500;
+                       timeout = max(timeout, SBP2_MIN_LOGIN_ORB_TIMEOUT);
+                       tgt->mgt_orb_timeout =
+                                 min(timeout, SBP2_MAX_LOGIN_ORB_TIMEOUT);
+
+                       if (timeout > tgt->mgt_orb_timeout)
+                               fw_notify("%s: config rom contains %ds "
+                                         "management ORB timeout, limiting "
+                                         "to %ds\n", tgt->bus_id,
+                                         timeout / 1000,
+                                         tgt->mgt_orb_timeout / 1000);
+                       break;
+
                case SBP2_CSR_LOGICAL_UNIT_NUMBER:
                        if (sbp2_add_logical_unit(tgt, value) < 0)
                                return -ENOMEM;
                        break;
 
                case SBP2_CSR_LOGICAL_UNIT_DIRECTORY:
-                       if (sbp2_scan_logical_unit_dir(tgt, ci.p + value) < 0)
+                       /* Adjust for the increment in the iterator */
+                       if (sbp2_scan_logical_unit_dir(tgt, ci.p - 1 + value) < 0)
                                return -ENOMEM;
                        break;
                }
@@ -805,12 +1074,12 @@ static void sbp2_init_workarounds(struct sbp2_target *tgt, u32 model,
                                  u32 firmware_revision)
 {
        int i;
-       unsigned w = sbp2_param_workarounds;
+       unsigned int w = sbp2_param_workarounds;
 
        if (w)
                fw_notify("Please notify linux1394-devel@lists.sourceforge.net "
                          "if you need the workarounds parameter for %s\n",
-                         tgt->unit->device.bus_id);
+                         tgt->bus_id);
 
        if (w & SBP2_WORKAROUND_OVERRIDE)
                goto out;
@@ -822,7 +1091,7 @@ static void sbp2_init_workarounds(struct sbp2_target *tgt, u32 model,
                        continue;
 
                if (sbp2_workarounds_table[i].model != model &&
-                   sbp2_workarounds_table[i].model != ~0)
+                   sbp2_workarounds_table[i].model != SBP2_ROM_VALUE_WILDCARD)
                        continue;
 
                w |= sbp2_workarounds_table[i].workarounds;
@@ -832,8 +1101,7 @@ static void sbp2_init_workarounds(struct sbp2_target *tgt, u32 model,
        if (w)
                fw_notify("Workarounds for %s: 0x%x "
                          "(firmware_revision 0x%06x, model_id 0x%06x)\n",
-                         tgt->unit->device.bus_id,
-                         w, firmware_revision, model);
+                         tgt->bus_id, w, firmware_revision, model);
        tgt->workarounds = w;
 }
 
@@ -848,6 +1116,10 @@ static int sbp2_probe(struct device *dev)
        struct Scsi_Host *shost;
        u32 model, firmware_revision;
 
+       if (dma_get_max_seg_size(device->card->device) > SBP2_MAX_SEG_SIZE)
+               BUG_ON(dma_set_max_seg_size(device->card->device,
+                                           SBP2_MAX_SEG_SIZE));
+
        shost = scsi_host_alloc(&scsi_driver_template, sizeof(*tgt));
        if (shost == NULL)
                return -ENOMEM;
@@ -857,6 +1129,8 @@ static int sbp2_probe(struct device *dev)
        tgt->unit = unit;
        kref_init(&tgt->kref);
        INIT_LIST_HEAD(&tgt->lu_list);
+       tgt->bus_id = dev_name(&unit->device);
+       tgt->guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];
 
        if (fw_device_enable_phys_dma(device) < 0)
                goto fail_shost_put;
@@ -864,25 +1138,34 @@ static int sbp2_probe(struct device *dev)
        if (scsi_add_host(shost, &unit->device) < 0)
                goto fail_shost_put;
 
-       /* Initialize to values that won't match anything in our table. */
-       firmware_revision = 0xff000000;
-       model = 0xff000000;
+       fw_device_get(device);
+       fw_unit_get(unit);
 
        /* implicit directory ID */
        tgt->directory_id = ((unit->directory - device->config_rom) * 4
                             + CSR_CONFIG_ROM) & 0xffffff;
 
+       firmware_revision = SBP2_ROM_VALUE_MISSING;
+       model             = SBP2_ROM_VALUE_MISSING;
+
        if (sbp2_scan_unit_dir(tgt, unit->directory, &model,
                               &firmware_revision) < 0)
                goto fail_tgt_put;
 
        sbp2_init_workarounds(tgt, model, firmware_revision);
 
-       get_device(&unit->device);
+       /*
+        * At S100 we can do 512 bytes per packet, at S200 1024 bytes,
+        * and so on up to 4096 bytes.  The SBP-2 max_payload field
+        * specifies the max payload size as 2 ^ (max_payload + 2), so
+        * if we set this to max_speed + 7, we get the right value.
+        */
+       tgt->max_payload = min(device->max_speed + 7, 10U);
+       tgt->max_payload = min(tgt->max_payload, device->card->max_receive - 1);
 
        /* Do the login in a workqueue so we can easily reschedule retries. */
        list_for_each_entry(lu, &tgt->lu_list, link)
-               sbp2_queue_work(lu, 0);
+               sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
        return 0;
 
  fail_tgt_put:
@@ -907,21 +1190,32 @@ static void sbp2_reconnect(struct work_struct *work)
 {
        struct sbp2_logical_unit *lu =
                container_of(work, struct sbp2_logical_unit, work.work);
-       struct fw_unit *unit = lu->tgt->unit;
-       struct fw_device *device = fw_device(unit->device.parent);
+       struct sbp2_target *tgt = lu->tgt;
+       struct fw_device *device = fw_device(tgt->unit->device.parent);
        int generation, node_id, local_node_id;
 
-       generation    = device->card->generation;
-       node_id       = device->node->node_id;
-       local_node_id = device->card->local_node->node_id;
+       if (fw_device_is_shutdown(device))
+               goto out;
+
+       generation    = device->generation;
+       smp_rmb();    /* node IDs must not be older than generation */
+       node_id       = device->node_id;
+       local_node_id = device->card->node_id;
 
        if (sbp2_send_management_orb(lu, node_id, generation,
                                     SBP2_RECONNECT_REQUEST,
                                     lu->login_id, NULL) < 0) {
-               if (lu->retries++ >= 5) {
-                       fw_error("failed to reconnect to %s\n",
-                                unit->device.bus_id);
-                       /* Fall back and try to log in again. */
+               /*
+                * If reconnect was impossible even though we are in the
+                * current generation, fall back and try to log in again.
+                *
+                * We could check for "Function rejected" status, but
+                * looking at the bus generation as simpler and more general.
+                */
+               smp_rmb(); /* get current card generation */
+               if (generation == device->card->generation ||
+                   lu->retries++ >= 5) {
+                       fw_error("%s: failed to reconnect\n", tgt->bus_id);
                        lu->retries = 0;
                        PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
                }
@@ -929,17 +1223,19 @@ static void sbp2_reconnect(struct work_struct *work)
                goto out;
        }
 
-       lu->generation        = generation;
-       lu->tgt->node_id      = node_id;
-       lu->tgt->address_high = local_node_id << 16;
+       tgt->node_id      = node_id;
+       tgt->address_high = local_node_id << 16;
+       smp_wmb();        /* node IDs must not be older than generation */
+       lu->generation    = generation;
 
-       fw_notify("reconnected to %s LUN %04x (%d retries)\n",
-                 unit->device.bus_id, lu->lun, lu->retries);
+       fw_notify("%s: reconnected to LUN %04x (%d retries)\n",
+                 tgt->bus_id, lu->lun, lu->retries);
 
        sbp2_agent_reset(lu);
        sbp2_cancel_orbs(lu);
+       sbp2_conditionally_unblock(lu);
  out:
-       sbp2_target_put(lu->tgt);
+       sbp2_target_put(tgt);
 }
 
 static void sbp2_update(struct fw_unit *unit)
@@ -954,6 +1250,7 @@ static void sbp2_update(struct fw_unit *unit)
         * Iteration over tgt->lu_list is therefore safe here.
         */
        list_for_each_entry(lu, &tgt->lu_list, link) {
+               sbp2_conditionally_block(lu);
                lu->retries = 0;
                sbp2_queue_work(lu, 0);
        }
@@ -983,8 +1280,20 @@ static struct fw_driver sbp2_driver = {
        .id_table = sbp2_id_table,
 };
 
-static unsigned int
-sbp2_status_to_sense_data(u8 *sbp2_status, u8 *sense_data)
+static void sbp2_unmap_scatterlist(struct device *card_device,
+                                  struct sbp2_command_orb *orb)
+{
+       if (scsi_sg_count(orb->cmd))
+               dma_unmap_sg(card_device, scsi_sglist(orb->cmd),
+                            scsi_sg_count(orb->cmd),
+                            orb->cmd->sc_data_direction);
+
+       if (orb->request.misc & cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT))
+               dma_unmap_single(card_device, orb->page_table_bus,
+                                sizeof(orb->page_table), DMA_TO_DEVICE);
+}
+
+static unsigned int sbp2_status_to_sense_data(u8 *sbp2_status, u8 *sense_data)
 {
        int sam_status;
 
@@ -1021,8 +1330,8 @@ sbp2_status_to_sense_data(u8 *sbp2_status, u8 *sense_data)
        }
 }
 
-static void
-complete_command_orb(struct sbp2_orb *base_orb, struct sbp2_status *status)
+static void complete_command_orb(struct sbp2_orb *base_orb,
+                                struct sbp2_status *status)
 {
        struct sbp2_command_orb *orb =
                container_of(base_orb, struct sbp2_command_orb, base);
@@ -1031,7 +1340,7 @@ complete_command_orb(struct sbp2_orb *base_orb, struct sbp2_status *status)
 
        if (status != NULL) {
                if (STATUS_GET_DEAD(*status))
-                       sbp2_agent_reset(orb->lu);
+                       sbp2_agent_reset_no_wait(orb->lu);
 
                switch (STATUS_GET_RESPONSE(*status)) {
                case SBP2_STATUS_REQUEST_COMPLETE:
@@ -1057,36 +1366,26 @@ complete_command_orb(struct sbp2_orb *base_orb, struct sbp2_status *status)
                 * or when sending the write (less likely).
                 */
                result = DID_BUS_BUSY << 16;
+               sbp2_conditionally_block(orb->lu);
        }
 
        dma_unmap_single(device->card->device, orb->base.request_bus,
                         sizeof(orb->request), DMA_TO_DEVICE);
-
-       if (scsi_sg_count(orb->cmd) > 0)
-               dma_unmap_sg(device->card->device, scsi_sglist(orb->cmd),
-                            scsi_sg_count(orb->cmd),
-                            orb->cmd->sc_data_direction);
-
-       if (orb->page_table_bus != 0)
-               dma_unmap_single(device->card->device, orb->page_table_bus,
-                                sizeof(orb->page_table), DMA_TO_DEVICE);
+       sbp2_unmap_scatterlist(device->card->device, orb);
 
        orb->cmd->result = result;
        orb->done(orb->cmd);
 }
 
-static int
-sbp2_map_scatterlist(struct sbp2_command_orb *orb, struct fw_device *device,
-                    struct sbp2_logical_unit *lu)
+static int sbp2_map_scatterlist(struct sbp2_command_orb *orb,
+               struct fw_device *device, struct sbp2_logical_unit *lu)
 {
-       struct scatterlist *sg;
-       int sg_len, l, i, j, count;
-       dma_addr_t sg_addr;
-
-       sg = scsi_sglist(orb->cmd);
-       count = dma_map_sg(device->card->device, sg, scsi_sg_count(orb->cmd),
-                          orb->cmd->sc_data_direction);
-       if (count == 0)
+       struct scatterlist *sg = scsi_sglist(orb->cmd);
+       int i, n;
+
+       n = dma_map_sg(device->card->device, sg, scsi_sg_count(orb->cmd),
+                      orb->cmd->sc_data_direction);
+       if (n == 0)
                goto fail;
 
        /*
@@ -1096,44 +1395,25 @@ sbp2_map_scatterlist(struct sbp2_command_orb *orb, struct fw_device *device,
         * as the second generation iPod which doesn't support page
         * tables.
         */
-       if (count == 1 && sg_dma_len(sg) < SBP2_MAX_SG_ELEMENT_LENGTH) {
-               orb->request.data_descriptor.high = lu->tgt->address_high;
-               orb->request.data_descriptor.low  = sg_dma_address(sg);
-               orb->request.misc |= COMMAND_ORB_DATA_SIZE(sg_dma_len(sg));
+       if (n == 1) {
+               orb->request.data_descriptor.high =
+                       cpu_to_be32(lu->tgt->address_high);
+               orb->request.data_descriptor.low  =
+                       cpu_to_be32(sg_dma_address(sg));
+               orb->request.misc |=
+                       cpu_to_be32(COMMAND_ORB_DATA_SIZE(sg_dma_len(sg)));
                return 0;
        }
 
-       /*
-        * Convert the scatterlist to an sbp2 page table.  If any
-        * scatterlist entries are too big for sbp2, we split them as we
-        * go.  Even if we ask the block I/O layer to not give us sg
-        * elements larger than 65535 bytes, some IOMMUs may merge sg elements
-        * during DMA mapping, and Linux currently doesn't prevent this.
-        */
-       for (i = 0, j = 0; i < count; i++, sg = sg_next(sg)) {
-               sg_len = sg_dma_len(sg);
-               sg_addr = sg_dma_address(sg);
-               while (sg_len) {
-                       /* FIXME: This won't get us out of the pinch. */
-                       if (unlikely(j >= ARRAY_SIZE(orb->page_table))) {
-                               fw_error("page table overflow\n");
-                               goto fail_page_table;
-                       }
-                       l = min(sg_len, SBP2_MAX_SG_ELEMENT_LENGTH);
-                       orb->page_table[j].low = sg_addr;
-                       orb->page_table[j].high = (l << 16);
-                       sg_addr += l;
-                       sg_len -= l;
-                       j++;
-               }
+       for_each_sg(sg, sg, n, i) {
+               orb->page_table[i].high = cpu_to_be32(sg_dma_len(sg) << 16);
+               orb->page_table[i].low = cpu_to_be32(sg_dma_address(sg));
        }
 
-       fw_memcpy_to_be32(orb->page_table, orb->page_table,
-                         sizeof(orb->page_table[0]) * j);
        orb->page_table_bus =
                dma_map_single(device->card->device, orb->page_table,
                               sizeof(orb->page_table), DMA_TO_DEVICE);
-       if (dma_mapping_error(orb->page_table_bus))
+       if (dma_mapping_error(device->card->device, orb->page_table_bus))
                goto fail_page_table;
 
        /*
@@ -1143,17 +1423,16 @@ sbp2_map_scatterlist(struct sbp2_command_orb *orb, struct fw_device *device,
         * initiator (i.e. us), but data_descriptor can refer to data
         * on other nodes so we need to put our ID in descriptor.high.
         */
-       orb->request.data_descriptor.high = lu->tgt->address_high;
-       orb->request.data_descriptor.low  = orb->page_table_bus;
-       orb->request.misc |=
-               COMMAND_ORB_PAGE_TABLE_PRESENT |
-               COMMAND_ORB_DATA_SIZE(j);
+       orb->request.data_descriptor.high = cpu_to_be32(lu->tgt->address_high);
+       orb->request.data_descriptor.low  = cpu_to_be32(orb->page_table_bus);
+       orb->request.misc |= cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT |
+                                        COMMAND_ORB_DATA_SIZE(n));
 
        return 0;
 
  fail_page_table:
-       dma_unmap_sg(device->card->device, sg, scsi_sg_count(orb->cmd),
-                    orb->cmd->sc_data_direction);
+       dma_unmap_sg(device->card->device, scsi_sglist(orb->cmd),
+                    scsi_sg_count(orb->cmd), orb->cmd->sc_data_direction);
  fail:
        return -ENOMEM;
 }
@@ -1165,8 +1444,7 @@ static int sbp2_scsi_queuecommand(struct scsi_cmnd *cmd, scsi_done_fn_t done)
        struct sbp2_logical_unit *lu = cmd->device->hostdata;
        struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
        struct sbp2_command_orb *orb;
-       unsigned max_payload;
-       int retval = SCSI_MLQUEUE_HOST_BUSY;
+       int generation, retval = SCSI_MLQUEUE_HOST_BUSY;
 
        /*
         * Bidirectional commands are not yet implemented, and unknown
@@ -1193,45 +1471,33 @@ static int sbp2_scsi_queuecommand(struct scsi_cmnd *cmd, scsi_done_fn_t done)
        orb->done = done;
        orb->cmd  = cmd;
 
-       orb->request.next.high   = SBP2_ORB_NULL;
-       orb->request.next.low    = 0x0;
-       /*
-        * At speed 100 we can do 512 bytes per packet, at speed 200,
-        * 1024 bytes per packet etc.  The SBP-2 max_payload field
-        * specifies the max payload size as 2 ^ (max_payload + 2), so
-        * if we set this to max_speed + 7, we get the right value.
-        */
-       max_payload = min(device->max_speed + 7,
-                         device->card->max_receive - 1);
-       orb->request.misc =
-               COMMAND_ORB_MAX_PAYLOAD(max_payload) |
+       orb->request.next.high = cpu_to_be32(SBP2_ORB_NULL);
+       orb->request.misc = cpu_to_be32(
+               COMMAND_ORB_MAX_PAYLOAD(lu->tgt->max_payload) |
                COMMAND_ORB_SPEED(device->max_speed) |
-               COMMAND_ORB_NOTIFY;
+               COMMAND_ORB_NOTIFY);
 
        if (cmd->sc_data_direction == DMA_FROM_DEVICE)
-               orb->request.misc |=
-                       COMMAND_ORB_DIRECTION(SBP2_DIRECTION_FROM_MEDIA);
-       else if (cmd->sc_data_direction == DMA_TO_DEVICE)
-               orb->request.misc |=
-                       COMMAND_ORB_DIRECTION(SBP2_DIRECTION_TO_MEDIA);
+               orb->request.misc |= cpu_to_be32(COMMAND_ORB_DIRECTION);
+
+       generation = device->generation;
+       smp_rmb();    /* sbp2_map_scatterlist looks at tgt->address_high */
 
        if (scsi_sg_count(cmd) && sbp2_map_scatterlist(orb, device, lu) < 0)
                goto out;
 
-       fw_memcpy_to_be32(&orb->request, &orb->request, sizeof(orb->request));
-
-       memset(orb->request.command_block,
-              0, sizeof(orb->request.command_block));
-       memcpy(orb->request.command_block, cmd->cmnd, COMMAND_SIZE(*cmd->cmnd));
+       memcpy(orb->request.command_block, cmd->cmnd, cmd->cmd_len);
 
        orb->base.callback = complete_command_orb;
        orb->base.request_bus =
                dma_map_single(device->card->device, &orb->request,
                               sizeof(orb->request), DMA_TO_DEVICE);
-       if (dma_mapping_error(orb->base.request_bus))
+       if (dma_mapping_error(device->card->device, orb->base.request_bus)) {
+               sbp2_unmap_scatterlist(device->card->device, orb);
                goto out;
+       }
 
-       sbp2_send_orb(&orb->base, lu, lu->tgt->node_id, lu->generation,
+       sbp2_send_orb(&orb->base, lu, lu->tgt->node_id, generation,
                      lu->command_block_agent_address + SBP2_ORB_POINTER);
        retval = 0;
  out:
@@ -1243,13 +1509,14 @@ static int sbp2_scsi_slave_alloc(struct scsi_device *sdev)
 {
        struct sbp2_logical_unit *lu = sdev->hostdata;
 
+       /* (Re-)Adding logical units via the SCSI stack is not supported. */
+       if (!lu)
+               return -ENOSYS;
+
        sdev->allow_restart = 1;
 
-       /*
-        * Update the dma alignment (minimum alignment requirements for
-        * start and end of DMA transfers) to be a sector
-        */
-       blk_queue_update_dma_alignment(sdev->request_queue, 511);
+       /* SBP-2 requires quadlet alignment of the data buffers. */
+       blk_queue_update_dma_alignment(sdev->request_queue, 4 - 1);
 
        if (lu->tgt->workarounds & SBP2_WORKAROUND_INQUIRY_36)
                sdev->inquiry_len = 36;
@@ -1263,6 +1530,9 @@ static int sbp2_scsi_slave_configure(struct scsi_device *sdev)
 
        sdev->use_10_for_rw = 1;
 
+       if (sbp2_param_exclusive_login)
+               sdev->manage_start_stop = 1;
+
        if (sdev->type == TYPE_ROM)
                sdev->use_10_for_ms = 1;
 
@@ -1273,9 +1543,14 @@ static int sbp2_scsi_slave_configure(struct scsi_device *sdev)
        if (lu->tgt->workarounds & SBP2_WORKAROUND_FIX_CAPACITY)
                sdev->fix_capacity = 1;
 
+       if (lu->tgt->workarounds & SBP2_WORKAROUND_POWER_CONDITION)
+               sdev->start_stop_pwr_cond = 1;
+
        if (lu->tgt->workarounds & SBP2_WORKAROUND_128K_MAX_TRANS)
                blk_queue_max_sectors(sdev->request_queue, 128 * 1024 / 512);
 
+       blk_queue_max_segment_size(sdev->request_queue, SBP2_MAX_SEG_SIZE);
+
        return 0;
 }
 
@@ -1287,7 +1562,7 @@ static int sbp2_scsi_abort(struct scsi_cmnd *cmd)
 {
        struct sbp2_logical_unit *lu = cmd->device->hostdata;
 
-       fw_notify("sbp2_scsi_abort\n");
+       fw_notify("%s: sbp2_scsi_abort\n", lu->tgt->bus_id);
        sbp2_agent_reset(lu);
        sbp2_cancel_orbs(lu);
 
@@ -1301,22 +1576,19 @@ static int sbp2_scsi_abort(struct scsi_cmnd *cmd)
  * This is the concatenation of target port identifier and logical unit
  * identifier as per SAM-2...SAM-4 annex A.
  */
-static ssize_t
-sbp2_sysfs_ieee1394_id_show(struct device *dev, struct device_attribute *attr,
-                           char *buf)
+static ssize_t sbp2_sysfs_ieee1394_id_show(struct device *dev,
+                       struct device_attribute *attr, char *buf)
 {
        struct scsi_device *sdev = to_scsi_device(dev);
        struct sbp2_logical_unit *lu;
-       struct fw_device *device;
 
        if (!sdev)
                return 0;
 
        lu = sdev->hostdata;
-       device = fw_device(lu->tgt->unit->device.parent);
 
-       return sprintf(buf, "%08x%08x:%06x:%04x\n",
-                       device->config_rom[3], device->config_rom[4],
+       return sprintf(buf, "%016llx:%06x:%04x\n",
+                       (unsigned long long)lu->tgt->guid,
                        lu->tgt->directory_id, lu->lun);
 }