SAFE public projects git trees. - safe/jmp/linux-2.6/blob - drivers/scsi/sg.c

   1 /*
   2  *  History:
   3  *  Started: Aug 9 by Lawrence Foard (entropy@world.std.com),
   4  *           to allow user process control of SCSI devices.
   5  *  Development Sponsored by Killy Corp. NY NY
   6  *
   7  * Original driver (sg.c):
   8  *        Copyright (C) 1992 Lawrence Foard
   9  * Version 2 and 3 extensions to driver:
  10  *        Copyright (C) 1998 - 2005 Douglas Gilbert
  11  *
  12  *  Modified  19-JAN-1998  Richard Gooch <rgooch@atnf.csiro.au>  Devfs support
  13  *
  14  * This program is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2, or (at your option)
  17  * any later version.
  18  *
  19  */
  20
  21 static int sg_version_num = 30534;      /* 2 digits for each component */
  22 #define SG_VERSION_STR "3.5.34"
  23
  24 /*
  25  *  D. P. Gilbert (dgilbert@interlog.com, dougg@triode.net.au), notes:
  26  *      - scsi logging is available via SCSI_LOG_TIMEOUT macros. First
  27  *        the kernel/module needs to be built with CONFIG_SCSI_LOGGING
  28  *        (otherwise the macros compile to empty statements).
  29  *
  30  */
  31 #include <linux/module.h>
  32
  33 #include <linux/fs.h>
  34 #include <linux/kernel.h>
  35 #include <linux/sched.h>
  36 #include <linux/string.h>
  37 #include <linux/mm.h>
  38 #include <linux/errno.h>
  39 #include <linux/mtio.h>
  40 #include <linux/ioctl.h>
  41 #include <linux/fcntl.h>
  42 #include <linux/init.h>
  43 #include <linux/poll.h>
  44 #include <linux/smp_lock.h>
  45 #include <linux/moduleparam.h>
  46 #include <linux/cdev.h>
  47 #include <linux/seq_file.h>
  48 #include <linux/blkdev.h>
  49 #include <linux/delay.h>
  50 #include <linux/scatterlist.h>
  51
  52 #include "scsi.h"
  53 #include <scsi/scsi_dbg.h>
  54 #include <scsi/scsi_host.h>
  55 #include <scsi/scsi_driver.h>
  56 #include <scsi/scsi_ioctl.h>
  57 #include <scsi/sg.h>
  58
  59 #include "scsi_logging.h"
  60
  61 #ifdef CONFIG_SCSI_PROC_FS
  62 #include <linux/proc_fs.h>
  63 static char *sg_version_date = "20060920";
  64
  65 static int sg_proc_init(void);
  66 static void sg_proc_cleanup(void);
  67 #endif
  68
  69 #define SG_ALLOW_DIO_DEF 0
  70 #define SG_ALLOW_DIO_CODE /* compile out by commenting this define */
  71
  72 #define SG_MAX_DEVS 32768
  73
  74 /*
  75  * Suppose you want to calculate the formula muldiv(x,m,d)=int(x * m / d)
  76  * Then when using 32 bit integers x * m may overflow during the calculation.
  77  * Replacing muldiv(x) by muldiv(x)=((x % d) * m) / d + int(x / d) * m
  78  * calculates the same, but prevents the overflow when both m and d
  79  * are "small" numbers (like HZ and USER_HZ).
  80  * Of course an overflow is inavoidable if the result of muldiv doesn't fit
  81  * in 32 bits.
  82  */
  83 #define MULDIV(X,MUL,DIV) ((((X % DIV) * MUL) / DIV) + ((X / DIV) * MUL))
  84
  85 #define SG_DEFAULT_TIMEOUT MULDIV(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
  86
  87 int sg_big_buff = SG_DEF_RESERVED_SIZE;
  88 /* N.B. This variable is readable and writeable via
  89    /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
  90    of this size (or less if there is not enough memory) will be reserved
  91    for use by this file descriptor. [Deprecated usage: this variable is also
  92    readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
  93    the kernel (i.e. it is not a module).] */
  94 static int def_reserved_size = -1;      /* picks up init parameter */
  95 static int sg_allow_dio = SG_ALLOW_DIO_DEF;
  96
  97 static int scatter_elem_sz = SG_SCATTER_SZ;
  98 static int scatter_elem_sz_prev = SG_SCATTER_SZ;
  99
 100 #define SG_SECTOR_SZ 512
 101 #define SG_SECTOR_MSK (SG_SECTOR_SZ - 1)
 102
 103 #define SG_DEV_ARR_LUMP 32      /* amount to over allocate sg_dev_arr by */
 104
 105 static int sg_add(struct class_device *, struct class_interface *);
 106 static void sg_remove(struct class_device *, struct class_interface *);
 107
 108 static DEFINE_RWLOCK(sg_dev_arr_lock);  /* Also used to lock
 109                                                            file descriptor list for device */
 110
 111 static struct class_interface sg_interface = {
 112         .add            = sg_add,
 113         .remove         = sg_remove,
 114 };
 115
 116 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
 117         unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
 118         unsigned short sglist_len; /* size of malloc'd scatter-gather list ++ */
 119         unsigned bufflen;       /* Size of (aggregate) data buffer */
 120         unsigned b_malloc_len;  /* actual len malloc'ed in buffer */
 121         struct scatterlist *buffer;/* scatter list */
 122         char dio_in_use;        /* 0->indirect IO (or mmap), 1->dio */
 123         unsigned char cmd_opcode; /* first byte of command */
 124 } Sg_scatter_hold;
 125
 126 struct sg_device;               /* forward declarations */
 127 struct sg_fd;
 128
 129 typedef struct sg_request {     /* SG_MAX_QUEUE requests outstanding per file */
 130         struct sg_request *nextrp;      /* NULL -> tail request (slist) */
 131         struct sg_fd *parentfp; /* NULL -> not in use */
 132         Sg_scatter_hold data;   /* hold buffer, perhaps scatter list */
 133         sg_io_hdr_t header;     /* scsi command+info, see <scsi/sg.h> */
 134         unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
 135         char res_used;          /* 1 -> using reserve buffer, 0 -> not ... */
 136         char orphan;            /* 1 -> drop on sight, 0 -> normal */
 137         char sg_io_owned;       /* 1 -> packet belongs to SG_IO */
 138         volatile char done;     /* 0->before bh, 1->before read, 2->read */
 139 } Sg_request;
 140
 141 typedef struct sg_fd {          /* holds the state of a file descriptor */
 142         struct sg_fd *nextfp;   /* NULL when last opened fd on this device */
 143         struct sg_device *parentdp;     /* owning device */
 144         wait_queue_head_t read_wait;    /* queue read until command done */
 145         rwlock_t rq_list_lock;  /* protect access to list in req_arr */
 146         int timeout;            /* defaults to SG_DEFAULT_TIMEOUT      */
 147         int timeout_user;       /* defaults to SG_DEFAULT_TIMEOUT_USER */
 148         Sg_scatter_hold reserve;        /* buffer held for this file descriptor */
 149         unsigned save_scat_len; /* original length of trunc. scat. element */
 150         Sg_request *headrp;     /* head of request slist, NULL->empty */
 151         struct fasync_struct *async_qp; /* used by asynchronous notification */
 152         Sg_request req_arr[SG_MAX_QUEUE];       /* used as singly-linked list */
 153         char low_dma;           /* as in parent but possibly overridden to 1 */
 154         char force_packid;      /* 1 -> pack_id input to read(), 0 -> ignored */
 155         volatile char closed;   /* 1 -> fd closed but request(s) outstanding */
 156         char cmd_q;             /* 1 -> allow command queuing, 0 -> don't */
 157         char next_cmd_len;      /* 0 -> automatic (def), >0 -> use on next write() */
 158         char keep_orphan;       /* 0 -> drop orphan (def), 1 -> keep for read() */
 159         char mmap_called;       /* 0 -> mmap() never called on this fd */
 160 } Sg_fd;
 161
 162 typedef struct sg_device { /* holds the state of each scsi generic device */
 163         struct scsi_device *device;
 164         wait_queue_head_t o_excl_wait;  /* queue open() when O_EXCL in use */
 165         int sg_tablesize;       /* adapter's max scatter-gather table size */
 166         Sg_fd *headfp;          /* first open fd belonging to this device */
 167         volatile char detached; /* 0->attached, 1->detached pending removal */
 168         volatile char exclude;  /* opened for exclusive access */
 169         char sgdebug;           /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
 170         struct gendisk *disk;
 171         struct cdev * cdev;     /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
 172 } Sg_device;
 173
 174 static int sg_fasync(int fd, struct file *filp, int mode);
 175 /* tasklet or soft irq callback */
 176 static void sg_cmd_done(void *data, char *sense, int result, int resid);
 177 static int sg_start_req(Sg_request * srp);
 178 static void sg_finish_rem_req(Sg_request * srp);
 179 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
 180 static int sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp,
 181                          int tablesize);
 182 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
 183                            Sg_request * srp);
 184 static ssize_t sg_new_write(Sg_fd * sfp, const char __user *buf, size_t count,
 185                             int blocking, int read_only, Sg_request ** o_srp);
 186 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
 187                            unsigned char *cmnd, int timeout, int blocking);
 188 static int sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
 189                       int wr_xf, int *countp, unsigned char __user **up);
 190 static int sg_write_xfer(Sg_request * srp);
 191 static int sg_read_xfer(Sg_request * srp);
 192 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
 193 static void sg_remove_scat(Sg_scatter_hold * schp);
 194 static void sg_build_reserve(Sg_fd * sfp, int req_size);
 195 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
 196 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
 197 static struct page *sg_page_malloc(int rqSz, int lowDma, int *retSzp);
 198 static void sg_page_free(struct page *page, int size);
 199 static Sg_fd *sg_add_sfp(Sg_device * sdp, int dev);
 200 static int sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
 201 static void __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
 202 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
 203 static Sg_request *sg_add_request(Sg_fd * sfp);
 204 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
 205 static int sg_res_in_use(Sg_fd * sfp);
 206 static int sg_allow_access(unsigned char opcode, char dev_type);
 207 static int sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len);
 208 static Sg_device *sg_get_dev(int dev);
 209 #ifdef CONFIG_SCSI_PROC_FS
 210 static int sg_last_dev(void);
 211 #endif
 212
 213 static Sg_device **sg_dev_arr = NULL;
 214 static int sg_dev_max;
 215 static int sg_nr_dev;
 216
 217 #define SZ_SG_HEADER sizeof(struct sg_header)
 218 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
 219 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
 220 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
 221
 222 static int
 223 sg_open(struct inode *inode, struct file *filp)
 224 {
 225         int dev = iminor(inode);
 226         int flags = filp->f_flags;
 227         struct request_queue *q;
 228         Sg_device *sdp;
 229         Sg_fd *sfp;
 230         int res;
 231         int retval;
 232
 233         nonseekable_open(inode, filp);
 234         SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags));
 235         sdp = sg_get_dev(dev);
 236         if ((!sdp) || (!sdp->device))
 237                 return -ENXIO;
 238         if (sdp->detached)
 239                 return -ENODEV;
 240
 241         /* This driver's module count bumped by fops_get in <linux/fs.h> */
 242         /* Prevent the device driver from vanishing while we sleep */
 243         retval = scsi_device_get(sdp->device);
 244         if (retval)
 245                 return retval;
 246
 247         if (!((flags & O_NONBLOCK) ||
 248               scsi_block_when_processing_errors(sdp->device))) {
 249                 retval = -ENXIO;
 250                 /* we are in error recovery for this device */
 251                 goto error_out;
 252         }
 253
 254         if (flags & O_EXCL) {
 255                 if (O_RDONLY == (flags & O_ACCMODE)) {
 256                         retval = -EPERM; /* Can't lock it with read only access */
 257                         goto error_out;
 258                 }
 259                 if (sdp->headfp && (flags & O_NONBLOCK)) {
 260                         retval = -EBUSY;
 261                         goto error_out;
 262                 }
 263                 res = 0;
 264                 __wait_event_interruptible(sdp->o_excl_wait,
 265                         ((sdp->headfp || sdp->exclude) ? 0 : (sdp->exclude = 1)), res);
 266                 if (res) {
 267                         retval = res;   /* -ERESTARTSYS because signal hit process */
 268                         goto error_out;
 269                 }
 270         } else if (sdp->exclude) {      /* some other fd has an exclusive lock on dev */
 271                 if (flags & O_NONBLOCK) {
 272                         retval = -EBUSY;
 273                         goto error_out;
 274                 }
 275                 res = 0;
 276                 __wait_event_interruptible(sdp->o_excl_wait, (!sdp->exclude),
 277                                            res);
 278                 if (res) {
 279                         retval = res;   /* -ERESTARTSYS because signal hit process */
 280                         goto error_out;
 281                 }
 282         }
 283         if (sdp->detached) {
 284                 retval = -ENODEV;
 285                 goto error_out;
 286         }
 287         if (!sdp->headfp) {     /* no existing opens on this device */
 288                 sdp->sgdebug = 0;
 289                 q = sdp->device->request_queue;
 290                 sdp->sg_tablesize = min(q->max_hw_segments,
 291                                         q->max_phys_segments);
 292         }
 293         if ((sfp = sg_add_sfp(sdp, dev)))
 294                 filp->private_data = sfp;
 295         else {
 296                 if (flags & O_EXCL)
 297                         sdp->exclude = 0;       /* undo if error */
 298                 retval = -ENOMEM;
 299                 goto error_out;
 300         }
 301         return 0;
 302
 303       error_out:
 304         scsi_device_put(sdp->device);
 305         return retval;
 306 }
 307
 308 /* Following function was formerly called 'sg_close' */
 309 static int
 310 sg_release(struct inode *inode, struct file *filp)
 311 {
 312         Sg_device *sdp;
 313         Sg_fd *sfp;
 314
 315         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 316                 return -ENXIO;
 317         SCSI_LOG_TIMEOUT(3, printk("sg_release: %s\n", sdp->disk->disk_name));
 318         sg_fasync(-1, filp, 0); /* remove filp from async notification list */
 319         if (0 == sg_remove_sfp(sdp, sfp)) {     /* Returns 1 when sdp gone */
 320                 if (!sdp->detached) {
 321                         scsi_device_put(sdp->device);
 322                 }
 323                 sdp->exclude = 0;
 324                 wake_up_interruptible(&sdp->o_excl_wait);
 325         }
 326         return 0;
 327 }
 328
 329 static ssize_t
 330 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
 331 {
 332         Sg_device *sdp;
 333         Sg_fd *sfp;
 334         Sg_request *srp;
 335         int req_pack_id = -1;
 336         sg_io_hdr_t *hp;
 337         struct sg_header *old_hdr = NULL;
 338         int retval = 0;
 339
 340         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 341                 return -ENXIO;
 342         SCSI_LOG_TIMEOUT(3, printk("sg_read: %s, count=%d\n",
 343                                    sdp->disk->disk_name, (int) count));
 344
 345         if (!access_ok(VERIFY_WRITE, buf, count))
 346                 return -EFAULT;
 347         if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
 348                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 349                 if (!old_hdr)
 350                         return -ENOMEM;
 351                 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
 352                         retval = -EFAULT;
 353                         goto free_old_hdr;
 354                 }
 355                 if (old_hdr->reply_len < 0) {
 356                         if (count >= SZ_SG_IO_HDR) {
 357                                 sg_io_hdr_t *new_hdr;
 358                                 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
 359                                 if (!new_hdr) {
 360                                         retval = -ENOMEM;
 361                                         goto free_old_hdr;
 362                                 }
 363                                 retval =__copy_from_user
 364                                     (new_hdr, buf, SZ_SG_IO_HDR);
 365                                 req_pack_id = new_hdr->pack_id;
 366                                 kfree(new_hdr);
 367                                 if (retval) {
 368                                         retval = -EFAULT;
 369                                         goto free_old_hdr;
 370                                 }
 371                         }
 372                 } else
 373                         req_pack_id = old_hdr->pack_id;
 374         }
 375         srp = sg_get_rq_mark(sfp, req_pack_id);
 376         if (!srp) {             /* now wait on packet to arrive */
 377                 if (sdp->detached) {
 378                         retval = -ENODEV;
 379                         goto free_old_hdr;
 380                 }
 381                 if (filp->f_flags & O_NONBLOCK) {
 382                         retval = -EAGAIN;
 383                         goto free_old_hdr;
 384                 }
 385                 while (1) {
 386                         retval = 0; /* following macro beats race condition */
 387                         __wait_event_interruptible(sfp->read_wait,
 388                                 (sdp->detached ||
 389                                 (srp = sg_get_rq_mark(sfp, req_pack_id))),
 390                                 retval);
 391                         if (sdp->detached) {
 392                                 retval = -ENODEV;
 393                                 goto free_old_hdr;
 394                         }
 395                         if (0 == retval)
 396                                 break;
 397
 398                         /* -ERESTARTSYS as signal hit process */
 399                         goto free_old_hdr;
 400                 }
 401         }
 402         if (srp->header.interface_id != '\0') {
 403                 retval = sg_new_read(sfp, buf, count, srp);
 404                 goto free_old_hdr;
 405         }
 406
 407         hp = &srp->header;
 408         if (old_hdr == NULL) {
 409                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 410                 if (! old_hdr) {
 411                         retval = -ENOMEM;
 412                         goto free_old_hdr;
 413                 }
 414         }
 415         memset(old_hdr, 0, SZ_SG_HEADER);
 416         old_hdr->reply_len = (int) hp->timeout;
 417         old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
 418         old_hdr->pack_id = hp->pack_id;
 419         old_hdr->twelve_byte =
 420             ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
 421         old_hdr->target_status = hp->masked_status;
 422         old_hdr->host_status = hp->host_status;
 423         old_hdr->driver_status = hp->driver_status;
 424         if ((CHECK_CONDITION & hp->masked_status) ||
 425             (DRIVER_SENSE & hp->driver_status))
 426                 memcpy(old_hdr->sense_buffer, srp->sense_b,
 427                        sizeof (old_hdr->sense_buffer));
 428         switch (hp->host_status) {
 429         /* This setup of 'result' is for backward compatibility and is best
 430            ignored by the user who should use target, host + driver status */
 431         case DID_OK:
 432         case DID_PASSTHROUGH:
 433         case DID_SOFT_ERROR:
 434                 old_hdr->result = 0;
 435                 break;
 436         case DID_NO_CONNECT:
 437         case DID_BUS_BUSY:
 438         case DID_TIME_OUT:
 439                 old_hdr->result = EBUSY;
 440                 break;
 441         case DID_BAD_TARGET:
 442         case DID_ABORT:
 443         case DID_PARITY:
 444         case DID_RESET:
 445         case DID_BAD_INTR:
 446                 old_hdr->result = EIO;
 447                 break;
 448         case DID_ERROR:
 449                 old_hdr->result = (srp->sense_b[0] == 0 &&
 450                                   hp->masked_status == GOOD) ? 0 : EIO;
 451                 break;
 452         default:
 453                 old_hdr->result = EIO;
 454                 break;
 455         }
 456
 457         /* Now copy the result back to the user buffer.  */
 458         if (count >= SZ_SG_HEADER) {
 459                 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
 460                         retval = -EFAULT;
 461                         goto free_old_hdr;
 462                 }
 463                 buf += SZ_SG_HEADER;
 464                 if (count > old_hdr->reply_len)
 465                         count = old_hdr->reply_len;
 466                 if (count > SZ_SG_HEADER) {
 467                         if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
 468                                 retval = -EFAULT;
 469                                 goto free_old_hdr;
 470                         }
 471                 }
 472         } else
 473                 count = (old_hdr->result == 0) ? 0 : -EIO;
 474         sg_finish_rem_req(srp);
 475         retval = count;
 476 free_old_hdr:
 477         kfree(old_hdr);
 478         return retval;
 479 }
 480
 481 static ssize_t
 482 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
 483 {
 484         sg_io_hdr_t *hp = &srp->header;
 485         int err = 0;
 486         int len;
 487
 488         if (count < SZ_SG_IO_HDR) {
 489                 err = -EINVAL;
 490                 goto err_out;
 491         }
 492         hp->sb_len_wr = 0;
 493         if ((hp->mx_sb_len > 0) && hp->sbp) {
 494                 if ((CHECK_CONDITION & hp->masked_status) ||
 495                     (DRIVER_SENSE & hp->driver_status)) {
 496                         int sb_len = SCSI_SENSE_BUFFERSIZE;
 497                         sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
 498                         len = 8 + (int) srp->sense_b[7];        /* Additional sense length field */
 499                         len = (len > sb_len) ? sb_len : len;
 500                         if (copy_to_user(hp->sbp, srp->sense_b, len)) {
 501                                 err = -EFAULT;
 502                                 goto err_out;
 503                         }
 504                         hp->sb_len_wr = len;
 505                 }
 506         }
 507         if (hp->masked_status || hp->host_status || hp->driver_status)
 508                 hp->info |= SG_INFO_CHECK;
 509         if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
 510                 err = -EFAULT;
 511                 goto err_out;
 512         }
 513         err = sg_read_xfer(srp);
 514       err_out:
 515         sg_finish_rem_req(srp);
 516         return (0 == err) ? count : err;
 517 }
 518
 519 static ssize_t
 520 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
 521 {
 522         int mxsize, cmd_size, k;
 523         int input_size, blocking;
 524         unsigned char opcode;
 525         Sg_device *sdp;
 526         Sg_fd *sfp;
 527         Sg_request *srp;
 528         struct sg_header old_hdr;
 529         sg_io_hdr_t *hp;
 530         unsigned char cmnd[MAX_COMMAND_SIZE];
 531
 532         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 533                 return -ENXIO;
 534         SCSI_LOG_TIMEOUT(3, printk("sg_write: %s, count=%d\n",
 535                                    sdp->disk->disk_name, (int) count));
 536         if (sdp->detached)
 537                 return -ENODEV;
 538         if (!((filp->f_flags & O_NONBLOCK) ||
 539               scsi_block_when_processing_errors(sdp->device)))
 540                 return -ENXIO;
 541
 542         if (!access_ok(VERIFY_READ, buf, count))
 543                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 544         if (count < SZ_SG_HEADER)
 545                 return -EIO;
 546         if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
 547                 return -EFAULT;
 548         blocking = !(filp->f_flags & O_NONBLOCK);
 549         if (old_hdr.reply_len < 0)
 550                 return sg_new_write(sfp, buf, count, blocking, 0, NULL);
 551         if (count < (SZ_SG_HEADER + 6))
 552                 return -EIO;    /* The minimum scsi command length is 6 bytes. */
 553
 554         if (!(srp = sg_add_request(sfp))) {
 555                 SCSI_LOG_TIMEOUT(1, printk("sg_write: queue full\n"));
 556                 return -EDOM;
 557         }
 558         buf += SZ_SG_HEADER;
 559         __get_user(opcode, buf);
 560         if (sfp->next_cmd_len > 0) {
 561                 if (sfp->next_cmd_len > MAX_COMMAND_SIZE) {
 562                         SCSI_LOG_TIMEOUT(1, printk("sg_write: command length too long\n"));
 563                         sfp->next_cmd_len = 0;
 564                         sg_remove_request(sfp, srp);
 565                         return -EIO;
 566                 }
 567                 cmd_size = sfp->next_cmd_len;
 568                 sfp->next_cmd_len = 0;  /* reset so only this write() effected */
 569         } else {
 570                 cmd_size = COMMAND_SIZE(opcode);        /* based on SCSI command group */
 571                 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
 572                         cmd_size = 12;
 573         }
 574         SCSI_LOG_TIMEOUT(4, printk(
 575                 "sg_write:   scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
 576 /* Determine buffer size.  */
 577         input_size = count - cmd_size;
 578         mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
 579         mxsize -= SZ_SG_HEADER;
 580         input_size -= SZ_SG_HEADER;
 581         if (input_size < 0) {
 582                 sg_remove_request(sfp, srp);
 583                 return -EIO;    /* User did not pass enough bytes for this command. */
 584         }
 585         hp = &srp->header;
 586         hp->interface_id = '\0';        /* indicator of old interface tunnelled */
 587         hp->cmd_len = (unsigned char) cmd_size;
 588         hp->iovec_count = 0;
 589         hp->mx_sb_len = 0;
 590         if (input_size > 0)
 591                 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
 592                     SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
 593         else
 594                 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
 595         hp->dxfer_len = mxsize;
 596         hp->dxferp = (char __user *)buf + cmd_size;
 597         hp->sbp = NULL;
 598         hp->timeout = old_hdr.reply_len;        /* structure abuse ... */
 599         hp->flags = input_size; /* structure abuse ... */
 600         hp->pack_id = old_hdr.pack_id;
 601         hp->usr_ptr = NULL;
 602         if (__copy_from_user(cmnd, buf, cmd_size))
 603                 return -EFAULT;
 604         /*
 605          * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
 606          * but is is possible that the app intended SG_DXFER_TO_DEV, because there
 607          * is a non-zero input_size, so emit a warning.
 608          */
 609         if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV)
 610                 if (printk_ratelimit())
 611                         printk(KERN_WARNING
 612                                "sg_write: data in/out %d/%d bytes for SCSI command 0x%x--"
 613                                "guessing data in;\n" KERN_WARNING "   "
 614                                "program %s not setting count and/or reply_len properly\n",
 615                                old_hdr.reply_len - (int)SZ_SG_HEADER,
 616                                input_size, (unsigned int) cmnd[0],
 617                                current->comm);
 618         k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
 619         return (k < 0) ? k : count;
 620 }
 621
 622 static ssize_t
 623 sg_new_write(Sg_fd * sfp, const char __user *buf, size_t count,
 624              int blocking, int read_only, Sg_request ** o_srp)
 625 {
 626         int k;
 627         Sg_request *srp;
 628         sg_io_hdr_t *hp;
 629         unsigned char cmnd[MAX_COMMAND_SIZE];
 630         int timeout;
 631         unsigned long ul_timeout;
 632
 633         if (count < SZ_SG_IO_HDR)
 634                 return -EINVAL;
 635         if (!access_ok(VERIFY_READ, buf, count))
 636                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 637
 638         sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
 639         if (!(srp = sg_add_request(sfp))) {
 640                 SCSI_LOG_TIMEOUT(1, printk("sg_new_write: queue full\n"));
 641                 return -EDOM;
 642         }
 643         hp = &srp->header;
 644         if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
 645                 sg_remove_request(sfp, srp);
 646                 return -EFAULT;
 647         }
 648         if (hp->interface_id != 'S') {
 649                 sg_remove_request(sfp, srp);
 650                 return -ENOSYS;
 651         }
 652         if (hp->flags & SG_FLAG_MMAP_IO) {
 653                 if (hp->dxfer_len > sfp->reserve.bufflen) {
 654                         sg_remove_request(sfp, srp);
 655                         return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
 656                 }
 657                 if (hp->flags & SG_FLAG_DIRECT_IO) {
 658                         sg_remove_request(sfp, srp);
 659                         return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
 660                 }
 661                 if (sg_res_in_use(sfp)) {
 662                         sg_remove_request(sfp, srp);
 663                         return -EBUSY;  /* reserve buffer already being used */
 664                 }
 665         }
 666         ul_timeout = msecs_to_jiffies(srp->header.timeout);
 667         timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
 668         if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
 669                 sg_remove_request(sfp, srp);
 670                 return -EMSGSIZE;
 671         }
 672         if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
 673                 sg_remove_request(sfp, srp);
 674                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 675         }
 676         if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
 677                 sg_remove_request(sfp, srp);
 678                 return -EFAULT;
 679         }
 680         if (read_only &&
 681             (!sg_allow_access(cmnd[0], sfp->parentdp->device->type))) {
 682                 sg_remove_request(sfp, srp);
 683                 return -EPERM;
 684         }
 685         k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
 686         if (k < 0)
 687                 return k;
 688         if (o_srp)
 689                 *o_srp = srp;
 690         return count;
 691 }
 692
 693 static int
 694 sg_common_write(Sg_fd * sfp, Sg_request * srp,
 695                 unsigned char *cmnd, int timeout, int blocking)
 696 {
 697         int k, data_dir;
 698         Sg_device *sdp = sfp->parentdp;
 699         sg_io_hdr_t *hp = &srp->header;
 700
 701         srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
 702         hp->status = 0;
 703         hp->masked_status = 0;
 704         hp->msg_status = 0;
 705         hp->info = 0;
 706         hp->host_status = 0;
 707         hp->driver_status = 0;
 708         hp->resid = 0;
 709         SCSI_LOG_TIMEOUT(4, printk("sg_common_write:  scsi opcode=0x%02x, cmd_size=%d\n",
 710                           (int) cmnd[0], (int) hp->cmd_len));
 711
 712         if ((k = sg_start_req(srp))) {
 713                 SCSI_LOG_TIMEOUT(1, printk("sg_write: start_req err=%d\n", k));
 714                 sg_finish_rem_req(srp);
 715                 return k;       /* probably out of space --> ENOMEM */
 716         }
 717         if ((k = sg_write_xfer(srp))) {
 718                 SCSI_LOG_TIMEOUT(1, printk("sg_write: write_xfer, bad address\n"));
 719                 sg_finish_rem_req(srp);
 720                 return k;
 721         }
 722         if (sdp->detached) {
 723                 sg_finish_rem_req(srp);
 724                 return -ENODEV;
 725         }
 726
 727         switch (hp->dxfer_direction) {
 728         case SG_DXFER_TO_FROM_DEV:
 729         case SG_DXFER_FROM_DEV:
 730                 data_dir = DMA_FROM_DEVICE;
 731                 break;
 732         case SG_DXFER_TO_DEV:
 733                 data_dir = DMA_TO_DEVICE;
 734                 break;
 735         case SG_DXFER_UNKNOWN:
 736                 data_dir = DMA_BIDIRECTIONAL;
 737                 break;
 738         default:
 739                 data_dir = DMA_NONE;
 740                 break;
 741         }
 742         hp->duration = jiffies_to_msecs(jiffies);
 743 /* Now send everything of to mid-level. The next time we hear about this
 744    packet is when sg_cmd_done() is called (i.e. a callback). */
 745         if (scsi_execute_async(sdp->device, cmnd, hp->cmd_len, data_dir, srp->data.buffer,
 746                                 hp->dxfer_len, srp->data.k_use_sg, timeout,
 747                                 SG_DEFAULT_RETRIES, srp, sg_cmd_done,
 748                                 GFP_ATOMIC)) {
 749                 SCSI_LOG_TIMEOUT(1, printk("sg_write: scsi_execute_async failed\n"));
 750                 /*
 751                  * most likely out of mem, but could also be a bad map
 752                  */
 753                 sg_finish_rem_req(srp);
 754                 return -ENOMEM;
 755         } else
 756                 return 0;
 757 }
 758
 759 static int
 760 sg_srp_done(Sg_request *srp, Sg_fd *sfp)
 761 {
 762         unsigned long iflags;
 763         int done;
 764
 765         read_lock_irqsave(&sfp->rq_list_lock, iflags);
 766         done = srp->done;
 767         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 768         return done;
 769 }
 770
 771 static int
 772 sg_ioctl(struct inode *inode, struct file *filp,
 773          unsigned int cmd_in, unsigned long arg)
 774 {
 775         void __user *p = (void __user *)arg;
 776         int __user *ip = p;
 777         int result, val, read_only;
 778         Sg_device *sdp;
 779         Sg_fd *sfp;
 780         Sg_request *srp;
 781         unsigned long iflags;
 782
 783         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 784                 return -ENXIO;
 785         SCSI_LOG_TIMEOUT(3, printk("sg_ioctl: %s, cmd=0x%x\n",
 786                                    sdp->disk->disk_name, (int) cmd_in));
 787         read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
 788
 789         switch (cmd_in) {
 790         case SG_IO:
 791                 {
 792                         int blocking = 1;       /* ignore O_NONBLOCK flag */
 793
 794                         if (sdp->detached)
 795                                 return -ENODEV;
 796                         if (!scsi_block_when_processing_errors(sdp->device))
 797                                 return -ENXIO;
 798                         if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
 799                                 return -EFAULT;
 800                         result =
 801                             sg_new_write(sfp, p, SZ_SG_IO_HDR,
 802                                          blocking, read_only, &srp);
 803                         if (result < 0)
 804                                 return result;
 805                         srp->sg_io_owned = 1;
 806                         while (1) {
 807                                 result = 0;     /* following macro to beat race condition */
 808                                 __wait_event_interruptible(sfp->read_wait,
 809                                         (sdp->detached || sfp->closed || sg_srp_done(srp, sfp)),
 810                                                            result);
 811                                 if (sdp->detached)
 812                                         return -ENODEV;
 813                                 if (sfp->closed)
 814                                         return 0;       /* request packet dropped already */
 815                                 if (0 == result)
 816                                         break;
 817                                 srp->orphan = 1;
 818                                 return result;  /* -ERESTARTSYS because signal hit process */
 819                         }
 820                         write_lock_irqsave(&sfp->rq_list_lock, iflags);
 821                         srp->done = 2;
 822                         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 823                         result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
 824                         return (result < 0) ? result : 0;
 825                 }
 826         case SG_SET_TIMEOUT:
 827                 result = get_user(val, ip);
 828                 if (result)
 829                         return result;
 830                 if (val < 0)
 831                         return -EIO;
 832                 if (val >= MULDIV (INT_MAX, USER_HZ, HZ))
 833                     val = MULDIV (INT_MAX, USER_HZ, HZ);
 834                 sfp->timeout_user = val;
 835                 sfp->timeout = MULDIV (val, HZ, USER_HZ);
 836
 837                 return 0;
 838         case SG_GET_TIMEOUT:    /* N.B. User receives timeout as return value */
 839                                 /* strange ..., for backward compatibility */
 840                 return sfp->timeout_user;
 841         case SG_SET_FORCE_LOW_DMA:
 842                 result = get_user(val, ip);
 843                 if (result)
 844                         return result;
 845                 if (val) {
 846                         sfp->low_dma = 1;
 847                         if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
 848                                 val = (int) sfp->reserve.bufflen;
 849                                 sg_remove_scat(&sfp->reserve);
 850                                 sg_build_reserve(sfp, val);
 851                         }
 852                 } else {
 853                         if (sdp->detached)
 854                                 return -ENODEV;
 855                         sfp->low_dma = sdp->device->host->unchecked_isa_dma;
 856                 }
 857                 return 0;
 858         case SG_GET_LOW_DMA:
 859                 return put_user((int) sfp->low_dma, ip);
 860         case SG_GET_SCSI_ID:
 861                 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
 862                         return -EFAULT;
 863                 else {
 864                         sg_scsi_id_t __user *sg_idp = p;
 865
 866                         if (sdp->detached)
 867                                 return -ENODEV;
 868                         __put_user((int) sdp->device->host->host_no,
 869                                    &sg_idp->host_no);
 870                         __put_user((int) sdp->device->channel,
 871                                    &sg_idp->channel);
 872                         __put_user((int) sdp->device->id, &sg_idp->scsi_id);
 873                         __put_user((int) sdp->device->lun, &sg_idp->lun);
 874                         __put_user((int) sdp->device->type, &sg_idp->scsi_type);
 875                         __put_user((short) sdp->device->host->cmd_per_lun,
 876                                    &sg_idp->h_cmd_per_lun);
 877                         __put_user((short) sdp->device->queue_depth,
 878                                    &sg_idp->d_queue_depth);
 879                         __put_user(0, &sg_idp->unused[0]);
 880                         __put_user(0, &sg_idp->unused[1]);
 881                         return 0;
 882                 }
 883         case SG_SET_FORCE_PACK_ID:
 884                 result = get_user(val, ip);
 885                 if (result)
 886                         return result;
 887                 sfp->force_packid = val ? 1 : 0;
 888                 return 0;
 889         case SG_GET_PACK_ID:
 890                 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
 891                         return -EFAULT;
 892                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 893                 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
 894                         if ((1 == srp->done) && (!srp->sg_io_owned)) {
 895                                 read_unlock_irqrestore(&sfp->rq_list_lock,
 896                                                        iflags);
 897                                 __put_user(srp->header.pack_id, ip);
 898                                 return 0;
 899                         }
 900                 }
 901                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 902                 __put_user(-1, ip);
 903                 return 0;
 904         case SG_GET_NUM_WAITING:
 905                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 906                 for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) {
 907                         if ((1 == srp->done) && (!srp->sg_io_owned))
 908                                 ++val;
 909                 }
 910                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 911                 return put_user(val, ip);
 912         case SG_GET_SG_TABLESIZE:
 913                 return put_user(sdp->sg_tablesize, ip);
 914         case SG_SET_RESERVED_SIZE:
 915                 result = get_user(val, ip);
 916                 if (result)
 917                         return result;
 918                 if (val < 0)
 919                         return -EINVAL;
 920                 if (val != sfp->reserve.bufflen) {
 921                         if (sg_res_in_use(sfp) || sfp->mmap_called)
 922                                 return -EBUSY;
 923                         sg_remove_scat(&sfp->reserve);
 924                         sg_build_reserve(sfp, val);
 925                 }
 926                 return 0;
 927         case SG_GET_RESERVED_SIZE:
 928                 val = (int) sfp->reserve.bufflen;
 929                 return put_user(val, ip);
 930         case SG_SET_COMMAND_Q:
 931                 result = get_user(val, ip);
 932                 if (result)
 933                         return result;
 934                 sfp->cmd_q = val ? 1 : 0;
 935                 return 0;
 936         case SG_GET_COMMAND_Q:
 937                 return put_user((int) sfp->cmd_q, ip);
 938         case SG_SET_KEEP_ORPHAN:
 939                 result = get_user(val, ip);
 940                 if (result)
 941                         return result;
 942                 sfp->keep_orphan = val;
 943                 return 0;
 944         case SG_GET_KEEP_ORPHAN:
 945                 return put_user((int) sfp->keep_orphan, ip);
 946         case SG_NEXT_CMD_LEN:
 947                 result = get_user(val, ip);
 948                 if (result)
 949                         return result;
 950                 sfp->next_cmd_len = (val > 0) ? val : 0;
 951                 return 0;
 952         case SG_GET_VERSION_NUM:
 953                 return put_user(sg_version_num, ip);
 954         case SG_GET_ACCESS_COUNT:
 955                 /* faked - we don't have a real access count anymore */
 956                 val = (sdp->device ? 1 : 0);
 957                 return put_user(val, ip);
 958         case SG_GET_REQUEST_TABLE:
 959                 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
 960                         return -EFAULT;
 961                 else {
 962                         sg_req_info_t *rinfo;
 963                         unsigned int ms;
 964
 965                         rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
 966                                                                 GFP_KERNEL);
 967                         if (!rinfo)
 968                                 return -ENOMEM;
 969                         read_lock_irqsave(&sfp->rq_list_lock, iflags);
 970                         for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE;
 971                              ++val, srp = srp ? srp->nextrp : srp) {
 972                                 memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
 973                                 if (srp) {
 974                                         rinfo[val].req_state = srp->done + 1;
 975                                         rinfo[val].problem =
 976                                             srp->header.masked_status &
 977                                             srp->header.host_status &
 978                                             srp->header.driver_status;
 979                                         if (srp->done)
 980                                                 rinfo[val].duration =
 981                                                         srp->header.duration;
 982                                         else {
 983                                                 ms = jiffies_to_msecs(jiffies);
 984                                                 rinfo[val].duration =
 985                                                     (ms > srp->header.duration) ?
 986                                                     (ms - srp->header.duration) : 0;
 987                                         }
 988                                         rinfo[val].orphan = srp->orphan;
 989                                         rinfo[val].sg_io_owned =
 990                                                         srp->sg_io_owned;
 991                                         rinfo[val].pack_id =
 992                                                         srp->header.pack_id;
 993                                         rinfo[val].usr_ptr =
 994                                                         srp->header.usr_ptr;
 995                                 }
 996                         }
 997                         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 998                         result = __copy_to_user(p, rinfo,
 999                                                 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1000                         result = result ? -EFAULT : 0;
1001                         kfree(rinfo);
1002                         return result;
1003                 }
1004         case SG_EMULATED_HOST:
1005                 if (sdp->detached)
1006                         return -ENODEV;
1007                 return put_user(sdp->device->host->hostt->emulated, ip);
1008         case SG_SCSI_RESET:
1009                 if (sdp->detached)
1010                         return -ENODEV;
1011                 if (filp->f_flags & O_NONBLOCK) {
1012                         if (scsi_host_in_recovery(sdp->device->host))
1013                                 return -EBUSY;
1014                 } else if (!scsi_block_when_processing_errors(sdp->device))
1015                         return -EBUSY;
1016                 result = get_user(val, ip);
1017                 if (result)
1018                         return result;
1019                 if (SG_SCSI_RESET_NOTHING == val)
1020                         return 0;
1021                 switch (val) {
1022                 case SG_SCSI_RESET_DEVICE:
1023                         val = SCSI_TRY_RESET_DEVICE;
1024                         break;
1025                 case SG_SCSI_RESET_BUS:
1026                         val = SCSI_TRY_RESET_BUS;
1027                         break;
1028                 case SG_SCSI_RESET_HOST:
1029                         val = SCSI_TRY_RESET_HOST;
1030                         break;
1031                 default:
1032                         return -EINVAL;
1033                 }
1034                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1035                         return -EACCES;
1036                 return (scsi_reset_provider(sdp->device, val) ==
1037                         SUCCESS) ? 0 : -EIO;
1038         case SCSI_IOCTL_SEND_COMMAND:
1039                 if (sdp->detached)
1040                         return -ENODEV;
1041                 if (read_only) {
1042                         unsigned char opcode = WRITE_6;
1043                         Scsi_Ioctl_Command __user *siocp = p;
1044
1045                         if (copy_from_user(&opcode, siocp->data, 1))
1046                                 return -EFAULT;
1047                         if (!sg_allow_access(opcode, sdp->device->type))
1048                                 return -EPERM;
1049                 }
1050                 return sg_scsi_ioctl(filp, sdp->device->request_queue, NULL, p);
1051         case SG_SET_DEBUG:
1052                 result = get_user(val, ip);
1053                 if (result)
1054                         return result;
1055                 sdp->sgdebug = (char) val;
1056                 return 0;
1057         case SCSI_IOCTL_GET_IDLUN:
1058         case SCSI_IOCTL_GET_BUS_NUMBER:
1059         case SCSI_IOCTL_PROBE_HOST:
1060         case SG_GET_TRANSFORM:
1061                 if (sdp->detached)
1062                         return -ENODEV;
1063                 return scsi_ioctl(sdp->device, cmd_in, p);
1064         default:
1065                 if (read_only)
1066                         return -EPERM;  /* don't know so take safe approach */
1067                 return scsi_ioctl(sdp->device, cmd_in, p);
1068         }
1069 }
1070
1071 #ifdef CONFIG_COMPAT
1072 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1073 {
1074         Sg_device *sdp;
1075         Sg_fd *sfp;
1076         struct scsi_device *sdev;
1077
1078         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1079                 return -ENXIO;
1080
1081         sdev = sdp->device;
1082         if (sdev->host->hostt->compat_ioctl) {
1083                 int ret;
1084
1085                 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1086
1087                 return ret;
1088         }
1089
1090         return -ENOIOCTLCMD;
1091 }
1092 #endif
1093
1094 static unsigned int
1095 sg_poll(struct file *filp, poll_table * wait)
1096 {
1097         unsigned int res = 0;
1098         Sg_device *sdp;
1099         Sg_fd *sfp;
1100         Sg_request *srp;
1101         int count = 0;
1102         unsigned long iflags;
1103
1104         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))
1105             || sfp->closed)
1106                 return POLLERR;
1107         poll_wait(filp, &sfp->read_wait, wait);
1108         read_lock_irqsave(&sfp->rq_list_lock, iflags);
1109         for (srp = sfp->headrp; srp; srp = srp->nextrp) {
1110                 /* if any read waiting, flag it */
1111                 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1112                         res = POLLIN | POLLRDNORM;
1113                 ++count;
1114         }
1115         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1116
1117         if (sdp->detached)
1118                 res |= POLLHUP;
1119         else if (!sfp->cmd_q) {
1120                 if (0 == count)
1121                         res |= POLLOUT | POLLWRNORM;
1122         } else if (count < SG_MAX_QUEUE)
1123                 res |= POLLOUT | POLLWRNORM;
1124         SCSI_LOG_TIMEOUT(3, printk("sg_poll: %s, res=0x%x\n",
1125                                    sdp->disk->disk_name, (int) res));
1126         return res;
1127 }
1128
1129 static int
1130 sg_fasync(int fd, struct file *filp, int mode)
1131 {
1132         int retval;
1133         Sg_device *sdp;
1134         Sg_fd *sfp;
1135
1136         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1137                 return -ENXIO;
1138         SCSI_LOG_TIMEOUT(3, printk("sg_fasync: %s, mode=%d\n",
1139                                    sdp->disk->disk_name, mode));
1140
1141         retval = fasync_helper(fd, filp, mode, &sfp->async_qp);
1142         return (retval < 0) ? retval : 0;
1143 }
1144
1145 static struct page *
1146 sg_vma_nopage(struct vm_area_struct *vma, unsigned long addr, int *type)
1147 {
1148         Sg_fd *sfp;
1149         struct page *page = NOPAGE_SIGBUS;
1150         unsigned long offset, len, sa;
1151         Sg_scatter_hold *rsv_schp;
1152         struct scatterlist *sg;
1153         int k;
1154
1155         if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1156                 return page;
1157         rsv_schp = &sfp->reserve;
1158         offset = addr - vma->vm_start;
1159         if (offset >= rsv_schp->bufflen)
1160                 return page;
1161         SCSI_LOG_TIMEOUT(3, printk("sg_vma_nopage: offset=%lu, scatg=%d\n",
1162                                    offset, rsv_schp->k_use_sg));
1163         sg = rsv_schp->buffer;
1164         sa = vma->vm_start;
1165         for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
1166              ++k, ++sg) {
1167                 len = vma->vm_end - sa;
1168                 len = (len < sg->length) ? len : sg->length;
1169                 if (offset < len) {
1170                         page = virt_to_page(page_address(sg->page) + offset);
1171                         get_page(page); /* increment page count */
1172                         break;
1173                 }
1174                 sa += len;
1175                 offset -= len;
1176         }
1177
1178         if (type)
1179                 *type = VM_FAULT_MINOR;
1180         return page;
1181 }
1182
1183 static struct vm_operations_struct sg_mmap_vm_ops = {
1184         .nopage = sg_vma_nopage,
1185 };
1186
1187 static int
1188 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1189 {
1190         Sg_fd *sfp;
1191         unsigned long req_sz, len, sa;
1192         Sg_scatter_hold *rsv_schp;
1193         int k;
1194         struct scatterlist *sg;
1195
1196         if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1197                 return -ENXIO;
1198         req_sz = vma->vm_end - vma->vm_start;
1199         SCSI_LOG_TIMEOUT(3, printk("sg_mmap starting, vm_start=%p, len=%d\n",
1200                                    (void *) vma->vm_start, (int) req_sz));
1201         if (vma->vm_pgoff)
1202                 return -EINVAL; /* want no offset */
1203         rsv_schp = &sfp->reserve;
1204         if (req_sz > rsv_schp->bufflen)
1205                 return -ENOMEM; /* cannot map more than reserved buffer */
1206
1207         sa = vma->vm_start;
1208         sg = rsv_schp->buffer;
1209         for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
1210              ++k, ++sg) {
1211                 len = vma->vm_end - sa;
1212                 len = (len < sg->length) ? len : sg->length;
1213                 sa += len;
1214         }
1215
1216         sfp->mmap_called = 1;
1217         vma->vm_flags |= VM_RESERVED;
1218         vma->vm_private_data = sfp;
1219         vma->vm_ops = &sg_mmap_vm_ops;
1220         return 0;
1221 }
1222
1223 /* This function is a "bottom half" handler that is called by the
1224  * mid level when a command is completed (or has failed). */
1225 static void
1226 sg_cmd_done(void *data, char *sense, int result, int resid)
1227 {
1228         Sg_request *srp = data;
1229         Sg_device *sdp = NULL;
1230         Sg_fd *sfp;
1231         unsigned long iflags;
1232         unsigned int ms;
1233
1234         if (NULL == srp) {
1235                 printk(KERN_ERR "sg_cmd_done: NULL request\n");
1236                 return;
1237         }
1238         sfp = srp->parentfp;
1239         if (sfp)
1240                 sdp = sfp->parentdp;
1241         if ((NULL == sdp) || sdp->detached) {
1242                 printk(KERN_INFO "sg_cmd_done: device detached\n");
1243                 return;
1244         }
1245
1246
1247         SCSI_LOG_TIMEOUT(4, printk("sg_cmd_done: %s, pack_id=%d, res=0x%x\n",
1248                 sdp->disk->disk_name, srp->header.pack_id, result));
1249         srp->header.resid = resid;
1250         ms = jiffies_to_msecs(jiffies);
1251         srp->header.duration = (ms > srp->header.duration) ?
1252                                 (ms - srp->header.duration) : 0;
1253         if (0 != result) {
1254                 struct scsi_sense_hdr sshdr;
1255
1256                 memcpy(srp->sense_b, sense, sizeof (srp->sense_b));
1257                 srp->header.status = 0xff & result;
1258                 srp->header.masked_status = status_byte(result);
1259                 srp->header.msg_status = msg_byte(result);
1260                 srp->header.host_status = host_byte(result);
1261                 srp->header.driver_status = driver_byte(result);
1262                 if ((sdp->sgdebug > 0) &&
1263                     ((CHECK_CONDITION == srp->header.masked_status) ||
1264                      (COMMAND_TERMINATED == srp->header.masked_status)))
1265                         __scsi_print_sense("sg_cmd_done", sense,
1266                                            SCSI_SENSE_BUFFERSIZE);
1267
1268                 /* Following if statement is a patch supplied by Eric Youngdale */
1269                 if (driver_byte(result) != 0
1270                     && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1271                     && !scsi_sense_is_deferred(&sshdr)
1272                     && sshdr.sense_key == UNIT_ATTENTION
1273                     && sdp->device->removable) {
1274                         /* Detected possible disc change. Set the bit - this */
1275                         /* may be used if there are filesystems using this device */
1276                         sdp->device->changed = 1;
1277                 }
1278         }
1279         /* Rely on write phase to clean out srp status values, so no "else" */
1280
1281         if (sfp->closed) {      /* whoops this fd already released, cleanup */
1282                 SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, freeing ...\n"));
1283                 sg_finish_rem_req(srp);
1284                 srp = NULL;
1285                 if (NULL == sfp->headrp) {
1286                         SCSI_LOG_TIMEOUT(1, printk("sg...bh: already closed, final cleanup\n"));
1287                         if (0 == sg_remove_sfp(sdp, sfp)) {     /* device still present */
1288                                 scsi_device_put(sdp->device);
1289                         }
1290                         sfp = NULL;
1291                 }
1292         } else if (srp && srp->orphan) {
1293                 if (sfp->keep_orphan)
1294                         srp->sg_io_owned = 0;
1295                 else {
1296                         sg_finish_rem_req(srp);
1297                         srp = NULL;
1298                 }
1299         }
1300         if (sfp && srp) {
1301                 /* Now wake up any sg_read() that is waiting for this packet. */
1302                 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1303                 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1304                 srp->done = 1;
1305                 wake_up_interruptible(&sfp->read_wait);
1306                 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1307         }
1308 }
1309
1310 static struct file_operations sg_fops = {
1311         .owner = THIS_MODULE,
1312         .read = sg_read,
1313         .write = sg_write,
1314         .poll = sg_poll,
1315         .ioctl = sg_ioctl,
1316 #ifdef CONFIG_COMPAT
1317         .compat_ioctl = sg_compat_ioctl,
1318 #endif
1319         .open = sg_open,
1320         .mmap = sg_mmap,
1321         .release = sg_release,
1322         .fasync = sg_fasync,
1323 };
1324
1325 static struct class *sg_sysfs_class;
1326
1327 static int sg_sysfs_valid = 0;
1328
1329 static int sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1330 {
1331         struct request_queue *q = scsidp->request_queue;
1332         Sg_device *sdp;
1333         unsigned long iflags;
1334         void *old_sg_dev_arr = NULL;
1335         int k, error;
1336
1337         sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1338         if (!sdp) {
1339                 printk(KERN_WARNING "kmalloc Sg_device failure\n");
1340                 return -ENOMEM;
1341         }
1342
1343         write_lock_irqsave(&sg_dev_arr_lock, iflags);
1344         if (unlikely(sg_nr_dev >= sg_dev_max)) {        /* try to resize */
1345                 Sg_device **tmp_da;
1346                 int tmp_dev_max = sg_nr_dev + SG_DEV_ARR_LUMP;
1347                 write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1348
1349                 tmp_da = kzalloc(tmp_dev_max * sizeof(Sg_device *), GFP_KERNEL);
1350                 if (unlikely(!tmp_da))
1351                         goto expand_failed;
1352
1353                 write_lock_irqsave(&sg_dev_arr_lock, iflags);
1354                 memcpy(tmp_da, sg_dev_arr, sg_dev_max * sizeof(Sg_device *));
1355                 old_sg_dev_arr = sg_dev_arr;
1356                 sg_dev_arr = tmp_da;
1357                 sg_dev_max = tmp_dev_max;
1358         }
1359
1360         for (k = 0; k < sg_dev_max; k++)
1361                 if (!sg_dev_arr[k])
1362                         break;
1363         if (unlikely(k >= SG_MAX_DEVS))
1364                 goto overflow;
1365
1366         SCSI_LOG_TIMEOUT(3, printk("sg_alloc: dev=%d \n", k));
1367         sprintf(disk->disk_name, "sg%d", k);
1368         disk->first_minor = k;
1369         sdp->disk = disk;
1370         sdp->device = scsidp;
1371         init_waitqueue_head(&sdp->o_excl_wait);
1372         sdp->sg_tablesize = min(q->max_hw_segments, q->max_phys_segments);
1373
1374         sg_nr_dev++;
1375         sg_dev_arr[k] = sdp;
1376         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1377         error = k;
1378
1379  out:
1380         if (error < 0)
1381                 kfree(sdp);
1382         kfree(old_sg_dev_arr);
1383         return error;
1384
1385  expand_failed:
1386         printk(KERN_WARNING "sg_alloc: device array cannot be resized\n");
1387         error = -ENOMEM;
1388         goto out;
1389
1390  overflow:
1391         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1392         sdev_printk(KERN_WARNING, scsidp,
1393                     "Unable to attach sg device type=%d, minor "
1394                     "number exceeds %d\n", scsidp->type, SG_MAX_DEVS - 1);
1395         error = -ENODEV;
1396         goto out;
1397 }
1398
1399 static int
1400 sg_add(struct class_device *cl_dev, struct class_interface *cl_intf)
1401 {
1402         struct scsi_device *scsidp = to_scsi_device(cl_dev->dev);
1403         struct gendisk *disk;
1404         Sg_device *sdp = NULL;
1405         struct cdev * cdev = NULL;
1406         int error, k;
1407         unsigned long iflags;
1408
1409         disk = alloc_disk(1);
1410         if (!disk) {
1411                 printk(KERN_WARNING "alloc_disk failed\n");
1412                 return -ENOMEM;
1413         }
1414         disk->major = SCSI_GENERIC_MAJOR;
1415
1416         error = -ENOMEM;
1417         cdev = cdev_alloc();
1418         if (!cdev) {
1419                 printk(KERN_WARNING "cdev_alloc failed\n");
1420                 goto out;
1421         }
1422         cdev->owner = THIS_MODULE;
1423         cdev->ops = &sg_fops;
1424
1425         error = sg_alloc(disk, scsidp);
1426         if (error < 0) {
1427                 printk(KERN_WARNING "sg_alloc failed\n");
1428                 goto out;
1429         }
1430         k = error;
1431         sdp = sg_dev_arr[k];
1432
1433         error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, k), 1);
1434         if (error)
1435                 goto cdev_add_err;
1436
1437         sdp->cdev = cdev;
1438         if (sg_sysfs_valid) {
1439                 struct class_device * sg_class_member;
1440
1441                 sg_class_member = class_device_create(sg_sysfs_class, NULL,
1442                                 MKDEV(SCSI_GENERIC_MAJOR, k),
1443                                 cl_dev->dev, "%s",
1444                                 disk->disk_name);
1445                 if (IS_ERR(sg_class_member))
1446                         printk(KERN_WARNING "sg_add: "
1447                                 "class_device_create failed\n");
1448                 class_set_devdata(sg_class_member, sdp);
1449                 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1450                                           &sg_class_member->kobj, "generic");
1451                 if (error)
1452                         printk(KERN_ERR "sg_add: unable to make symlink "
1453                                         "'generic' back to sg%d\n", k);
1454         } else
1455                 printk(KERN_WARNING "sg_add: sg_sys INvalid\n");
1456
1457         sdev_printk(KERN_NOTICE, scsidp,
1458                     "Attached scsi generic sg%d type %d\n", k,scsidp->type);
1459
1460         return 0;
1461
1462 cdev_add_err:
1463         write_lock_irqsave(&sg_dev_arr_lock, iflags);
1464         kfree(sg_dev_arr[k]);
1465         sg_dev_arr[k] = NULL;
1466         sg_nr_dev--;
1467         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1468
1469 out:
1470         put_disk(disk);
1471         if (cdev)
1472                 cdev_del(cdev);
1473         return error;
1474 }
1475
1476 static void
1477 sg_remove(struct class_device *cl_dev, struct class_interface *cl_intf)
1478 {
1479         struct scsi_device *scsidp = to_scsi_device(cl_dev->dev);
1480         Sg_device *sdp = NULL;
1481         unsigned long iflags;
1482         Sg_fd *sfp;
1483         Sg_fd *tsfp;
1484         Sg_request *srp;
1485         Sg_request *tsrp;
1486         int k, delay;
1487
1488         if (NULL == sg_dev_arr)
1489                 return;
1490         delay = 0;
1491         write_lock_irqsave(&sg_dev_arr_lock, iflags);
1492         for (k = 0; k < sg_dev_max; k++) {
1493                 sdp = sg_dev_arr[k];
1494                 if ((NULL == sdp) || (sdp->device != scsidp))
1495                         continue;       /* dirty but lowers nesting */
1496                 if (sdp->headfp) {
1497                         sdp->detached = 1;
1498                         for (sfp = sdp->headfp; sfp; sfp = tsfp) {
1499                                 tsfp = sfp->nextfp;
1500                                 for (srp = sfp->headrp; srp; srp = tsrp) {
1501                                         tsrp = srp->nextrp;
1502                                         if (sfp->closed || (0 == sg_srp_done(srp, sfp)))
1503                                                 sg_finish_rem_req(srp);
1504                                 }
1505                                 if (sfp->closed) {
1506                                         scsi_device_put(sdp->device);
1507                                         __sg_remove_sfp(sdp, sfp);
1508                                 } else {
1509                                         delay = 1;
1510                                         wake_up_interruptible(&sfp->read_wait);
1511                                         kill_fasync(&sfp->async_qp, SIGPOLL,
1512                                                     POLL_HUP);
1513                                 }
1514                         }
1515                         SCSI_LOG_TIMEOUT(3, printk("sg_detach: dev=%d, dirty\n", k));
1516                         if (NULL == sdp->headfp) {
1517                                 sg_dev_arr[k] = NULL;
1518                         }
1519                 } else {        /* nothing active, simple case */
1520                         SCSI_LOG_TIMEOUT(3, printk("sg_detach: dev=%d\n", k));
1521                         sg_dev_arr[k] = NULL;
1522                 }
1523                 sg_nr_dev--;
1524                 break;
1525         }
1526         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1527
1528         if (sdp) {
1529                 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1530                 class_device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, k));
1531                 cdev_del(sdp->cdev);
1532                 sdp->cdev = NULL;
1533                 put_disk(sdp->disk);
1534                 sdp->disk = NULL;
1535                 if (NULL == sdp->headfp)
1536                         kfree((char *) sdp);
1537         }
1538
1539         if (delay)
1540                 msleep(10);     /* dirty detach so delay device destruction */
1541 }
1542
1543 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1544 module_param_named(def_reserved_size, def_reserved_size, int,
1545                    S_IRUGO | S_IWUSR);
1546 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1547
1548 MODULE_AUTHOR("Douglas Gilbert");
1549 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1550 MODULE_LICENSE("GPL");
1551 MODULE_VERSION(SG_VERSION_STR);
1552 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1553
1554 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1555                 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1556 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1557 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1558
1559 static int __init
1560 init_sg(void)
1561 {
1562         int rc;
1563
1564         if (scatter_elem_sz < PAGE_SIZE) {
1565                 scatter_elem_sz = PAGE_SIZE;
1566                 scatter_elem_sz_prev = scatter_elem_sz;
1567         }
1568         if (def_reserved_size >= 0)
1569                 sg_big_buff = def_reserved_size;
1570         else
1571                 def_reserved_size = sg_big_buff;
1572
1573         rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1574                                     SG_MAX_DEVS, "sg");
1575         if (rc)
1576                 return rc;
1577         sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1578         if ( IS_ERR(sg_sysfs_class) ) {
1579                 rc = PTR_ERR(sg_sysfs_class);
1580                 goto err_out;
1581         }
1582         sg_sysfs_valid = 1;
1583         rc = scsi_register_interface(&sg_interface);
1584         if (0 == rc) {
1585 #ifdef CONFIG_SCSI_PROC_FS
1586                 sg_proc_init();
1587 #endif                          /* CONFIG_SCSI_PROC_FS */
1588                 return 0;
1589         }
1590         class_destroy(sg_sysfs_class);
1591 err_out:
1592         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1593         return rc;
1594 }
1595
1596 static void __exit
1597 exit_sg(void)
1598 {
1599 #ifdef CONFIG_SCSI_PROC_FS
1600         sg_proc_cleanup();
1601 #endif                          /* CONFIG_SCSI_PROC_FS */
1602         scsi_unregister_interface(&sg_interface);
1603         class_destroy(sg_sysfs_class);
1604         sg_sysfs_valid = 0;
1605         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1606                                  SG_MAX_DEVS);
1607         kfree((char *)sg_dev_arr);
1608         sg_dev_arr = NULL;
1609         sg_dev_max = 0;
1610 }
1611
1612 static int
1613 sg_start_req(Sg_request * srp)
1614 {
1615         int res;
1616         Sg_fd *sfp = srp->parentfp;
1617         sg_io_hdr_t *hp = &srp->header;
1618         int dxfer_len = (int) hp->dxfer_len;
1619         int dxfer_dir = hp->dxfer_direction;
1620         Sg_scatter_hold *req_schp = &srp->data;
1621         Sg_scatter_hold *rsv_schp = &sfp->reserve;
1622
1623         SCSI_LOG_TIMEOUT(4, printk("sg_start_req: dxfer_len=%d\n", dxfer_len));
1624         if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1625                 return 0;
1626         if (sg_allow_dio && (hp->flags & SG_FLAG_DIRECT_IO) &&
1627             (dxfer_dir != SG_DXFER_UNKNOWN) && (0 == hp->iovec_count) &&
1628             (!sfp->parentdp->device->host->unchecked_isa_dma)) {
1629                 res = sg_build_direct(srp, sfp, dxfer_len);
1630                 if (res <= 0)   /* -ve -> error, 0 -> done, 1 -> try indirect */
1631                         return res;
1632         }
1633         if ((!sg_res_in_use(sfp)) && (dxfer_len <= rsv_schp->bufflen))
1634                 sg_link_reserve(sfp, srp, dxfer_len);
1635         else {
1636                 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1637                 if (res) {
1638                         sg_remove_scat(req_schp);
1639                         return res;
1640                 }
1641         }
1642         return 0;
1643 }
1644
1645 static void
1646 sg_finish_rem_req(Sg_request * srp)
1647 {
1648         Sg_fd *sfp = srp->parentfp;
1649         Sg_scatter_hold *req_schp = &srp->data;
1650
1651         SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n", (int) srp->res_used));
1652         if (srp->res_used)
1653                 sg_unlink_reserve(sfp, srp);
1654         else
1655                 sg_remove_scat(req_schp);
1656         sg_remove_request(sfp, srp);
1657 }
1658
1659 static int
1660 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1661 {
1662         int sg_bufflen = tablesize * sizeof(struct scatterlist);
1663         gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1664
1665         /*
1666          * TODO: test without low_dma, we should not need it since
1667          * the block layer will bounce the buffer for us
1668          *
1669          * XXX(hch): we shouldn't need GFP_DMA for the actual S/G list.
1670          */
1671         if (sfp->low_dma)
1672                  gfp_flags |= GFP_DMA;
1673         schp->buffer = kzalloc(sg_bufflen, gfp_flags);
1674         if (!schp->buffer)
1675                 return -ENOMEM;
1676         schp->sglist_len = sg_bufflen;
1677         return tablesize;       /* number of scat_gath elements allocated */
1678 }
1679
1680 #ifdef SG_ALLOW_DIO_CODE
1681 /* vvvvvvvv  following code borrowed from st driver's direct IO vvvvvvvvv */
1682         /* TODO: hopefully we can use the generic block layer code */
1683
1684 /* Pin down user pages and put them into a scatter gather list. Returns <= 0 if
1685    - mapping of all pages not successful
1686    (i.e., either completely successful or fails)
1687 */
1688 static int
1689 st_map_user_pages(struct scatterlist *sgl, const unsigned int max_pages,
1690                   unsigned long uaddr, size_t count, int rw)
1691 {
1692         unsigned long end = (uaddr + count + PAGE_SIZE - 1) >> PAGE_SHIFT;
1693         unsigned long start = uaddr >> PAGE_SHIFT;
1694         const int nr_pages = end - start;
1695         int res, i, j;
1696         struct page **pages;
1697
1698         /* User attempted Overflow! */
1699         if ((uaddr + count) < uaddr)
1700                 return -EINVAL;
1701
1702         /* Too big */
1703         if (nr_pages > max_pages)
1704                 return -ENOMEM;
1705
1706         /* Hmm? */
1707         if (count == 0)
1708                 return 0;
1709
1710         if ((pages = kmalloc(max_pages * sizeof(*pages), GFP_ATOMIC)) == NULL)
1711                 return -ENOMEM;
1712
1713         /* Try to fault in all of the necessary pages */
1714         down_read(&current->mm->mmap_sem);
1715         /* rw==READ means read from drive, write into memory area */
1716         res = get_user_pages(
1717                 current,
1718                 current->mm,
1719                 uaddr,
1720                 nr_pages,
1721                 rw == READ,
1722                 0, /* don't force */
1723                 pages,
1724                 NULL);
1725         up_read(&current->mm->mmap_sem);
1726
1727         /* Errors and no page mapped should return here */
1728         if (res < nr_pages)
1729                 goto out_unmap;
1730
1731         for (i=0; i < nr_pages; i++) {
1732                 /* FIXME: flush superflous for rw==READ,
1733                  * probably wrong function for rw==WRITE
1734                  */
1735                 flush_dcache_page(pages[i]);
1736                 /* ?? Is locking needed? I don't think so */
1737                 /* if (TestSetPageLocked(pages[i]))
1738                    goto out_unlock; */
1739         }
1740
1741         sgl[0].page = pages[0];
1742         sgl[0].offset = uaddr & ~PAGE_MASK;
1743         if (nr_pages > 1) {
1744                 sgl[0].length = PAGE_SIZE - sgl[0].offset;
1745                 count -= sgl[0].length;
1746                 for (i=1; i < nr_pages ; i++) {
1747                         sgl[i].page = pages[i];
1748                         sgl[i].length = count < PAGE_SIZE ? count : PAGE_SIZE;
1749                         count -= PAGE_SIZE;
1750                 }
1751         }
1752         else {
1753                 sgl[0].length = count;
1754         }
1755
1756         kfree(pages);
1757         return nr_pages;
1758
1759  out_unmap:
1760         if (res > 0) {
1761                 for (j=0; j < res; j++)
1762                         page_cache_release(pages[j]);
1763                 res = 0;
1764         }
1765         kfree(pages);
1766         return res;
1767 }
1768
1769
1770 /* And unmap them... */
1771 static int
1772 st_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_pages,
1773                     int dirtied)
1774 {
1775         int i;
1776
1777         for (i=0; i < nr_pages; i++) {
1778                 struct page *page = sgl[i].page;
1779
1780                 if (dirtied)
1781                         SetPageDirty(page);
1782                 /* unlock_page(page); */
1783                 /* FIXME: cache flush missing for rw==READ
1784                  * FIXME: call the correct reference counting function
1785                  */
1786                 page_cache_release(page);
1787         }
1788
1789         return 0;
1790 }
1791
1792 /* ^^^^^^^^  above code borrowed from st driver's direct IO ^^^^^^^^^ */
1793 #endif
1794
1795
1796 /* Returns: -ve -> error, 0 -> done, 1 -> try indirect */
1797 static int
1798 sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len)
1799 {
1800 #ifdef SG_ALLOW_DIO_CODE
1801         sg_io_hdr_t *hp = &srp->header;
1802         Sg_scatter_hold *schp = &srp->data;
1803         int sg_tablesize = sfp->parentdp->sg_tablesize;
1804         int mx_sc_elems, res;
1805         struct scsi_device *sdev = sfp->parentdp->device;
1806
1807         if (((unsigned long)hp->dxferp &
1808                         queue_dma_alignment(sdev->request_queue)) != 0)
1809                 return 1;
1810
1811         mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1812         if (mx_sc_elems <= 0) {
1813                 return 1;
1814         }
1815         res = st_map_user_pages(schp->buffer, mx_sc_elems,
1816                                 (unsigned long)hp->dxferp, dxfer_len,
1817                                 (SG_DXFER_TO_DEV == hp->dxfer_direction) ? 1 : 0);
1818         if (res <= 0) {
1819                 sg_remove_scat(schp);
1820                 return 1;
1821         }
1822         schp->k_use_sg = res;
1823         schp->dio_in_use = 1;
1824         hp->info |= SG_INFO_DIRECT_IO;
1825         return 0;
1826 #else
1827         return 1;
1828 #endif
1829 }
1830
1831 static int
1832 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1833 {
1834         struct scatterlist *sg;
1835         int ret_sz = 0, k, rem_sz, num, mx_sc_elems;
1836         int sg_tablesize = sfp->parentdp->sg_tablesize;
1837         int blk_size = buff_size;
1838         struct page *p = NULL;
1839
1840         if ((blk_size < 0) || (!sfp))
1841                 return -EFAULT;
1842         if (0 == blk_size)
1843                 ++blk_size;     /* don't know why */
1844 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1845         blk_size = (blk_size + SG_SECTOR_MSK) & (~SG_SECTOR_MSK);
1846         SCSI_LOG_TIMEOUT(4, printk("sg_build_indirect: buff_size=%d, blk_size=%d\n",
1847                                    buff_size, blk_size));
1848
1849         /* N.B. ret_sz carried into this block ... */
1850         mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1851         if (mx_sc_elems < 0)
1852                 return mx_sc_elems;     /* most likely -ENOMEM */
1853
1854         num = scatter_elem_sz;
1855         if (unlikely(num != scatter_elem_sz_prev)) {
1856                 if (num < PAGE_SIZE) {
1857                         scatter_elem_sz = PAGE_SIZE;
1858                         scatter_elem_sz_prev = PAGE_SIZE;
1859                 } else
1860                         scatter_elem_sz_prev = num;
1861         }
1862         for (k = 0, sg = schp->buffer, rem_sz = blk_size;
1863              (rem_sz > 0) && (k < mx_sc_elems);
1864              ++k, rem_sz -= ret_sz, ++sg) {
1865
1866                 num = (rem_sz > scatter_elem_sz_prev) ?
1867                       scatter_elem_sz_prev : rem_sz;
1868                 p = sg_page_malloc(num, sfp->low_dma, &ret_sz);
1869                 if (!p)
1870                         return -ENOMEM;
1871
1872                 if (num == scatter_elem_sz_prev) {
1873                         if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1874                                 scatter_elem_sz = ret_sz;
1875                                 scatter_elem_sz_prev = ret_sz;
1876                         }
1877                 }
1878                 sg->page = p;
1879                 sg->length = ret_sz;
1880
1881                 SCSI_LOG_TIMEOUT(5, printk("sg_build_build: k=%d, a=0x%p, len=%d\n",
1882                                   k, p, ret_sz));
1883         }               /* end of for loop */
1884
1885         schp->k_use_sg = k;
1886         SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, rem_sz=%d\n", k, rem_sz));
1887
1888         schp->bufflen = blk_size;
1889         if (rem_sz > 0) /* must have failed */
1890                 return -ENOMEM;
1891
1892         return 0;
1893 }
1894
1895 static int
1896 sg_write_xfer(Sg_request * srp)
1897 {
1898         sg_io_hdr_t *hp = &srp->header;
1899         Sg_scatter_hold *schp = &srp->data;
1900         struct scatterlist *sg = schp->buffer;
1901         int num_xfer = 0;
1902         int j, k, onum, usglen, ksglen, res;
1903         int iovec_count = (int) hp->iovec_count;
1904         int dxfer_dir = hp->dxfer_direction;
1905         unsigned char *p;
1906         unsigned char __user *up;
1907         int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
1908
1909         if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_TO_DEV == dxfer_dir) ||
1910             (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
1911                 num_xfer = (int) (new_interface ? hp->dxfer_len : hp->flags);
1912                 if (schp->bufflen < num_xfer)
1913                         num_xfer = schp->bufflen;
1914         }
1915         if ((num_xfer <= 0) || (schp->dio_in_use) ||
1916             (new_interface
1917              && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
1918                 return 0;
1919
1920         SCSI_LOG_TIMEOUT(4, printk("sg_write_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
1921                           num_xfer, iovec_count, schp->k_use_sg));
1922         if (iovec_count) {
1923                 onum = iovec_count;
1924                 if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum))
1925                         return -EFAULT;
1926         } else
1927                 onum = 1;
1928
1929         ksglen = sg->length;
1930         p = page_address(sg->page);
1931         for (j = 0, k = 0; j < onum; ++j) {
1932                 res = sg_u_iovec(hp, iovec_count, j, 1, &usglen, &up);
1933                 if (res)
1934                         return res;
1935
1936                 for (; p; ++sg, ksglen = sg->length,
1937                      p = page_address(sg->page)) {
1938                         if (usglen <= 0)
1939                                 break;
1940                         if (ksglen > usglen) {
1941                                 if (usglen >= num_xfer) {
1942                                         if (__copy_from_user(p, up, num_xfer))
1943                                                 return -EFAULT;
1944                                         return 0;
1945                                 }
1946                                 if (__copy_from_user(p, up, usglen))
1947                                         return -EFAULT;
1948                                 p += usglen;
1949                                 ksglen -= usglen;
1950                                 break;
1951                         } else {
1952                                 if (ksglen >= num_xfer) {
1953                                         if (__copy_from_user(p, up, num_xfer))
1954                                                 return -EFAULT;
1955                                         return 0;
1956                                 }
1957                                 if (__copy_from_user(p, up, ksglen))
1958                                         return -EFAULT;
1959                                 up += ksglen;
1960                                 usglen -= ksglen;
1961                         }
1962                         ++k;
1963                         if (k >= schp->k_use_sg)
1964                                 return 0;
1965                 }
1966         }
1967
1968         return 0;
1969 }
1970
1971 static int
1972 sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
1973            int wr_xf, int *countp, unsigned char __user **up)
1974 {
1975         int num_xfer = (int) hp->dxfer_len;
1976         unsigned char __user *p = hp->dxferp;
1977         int count;
1978
1979         if (0 == sg_num) {
1980                 if (wr_xf && ('\0' == hp->interface_id))
1981                         count = (int) hp->flags;        /* holds "old" input_size */
1982                 else
1983                         count = num_xfer;
1984         } else {
1985                 sg_iovec_t iovec;
1986                 if (__copy_from_user(&iovec, p + ind*SZ_SG_IOVEC, SZ_SG_IOVEC))
1987                         return -EFAULT;
1988                 p = iovec.iov_base;
1989                 count = (int) iovec.iov_len;
1990         }
1991         if (!access_ok(wr_xf ? VERIFY_READ : VERIFY_WRITE, p, count))
1992                 return -EFAULT;
1993         if (up)
1994                 *up = p;
1995         if (countp)
1996                 *countp = count;
1997         return 0;
1998 }
1999
2000 static void
2001 sg_remove_scat(Sg_scatter_hold * schp)
2002 {
2003         SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
2004         if (schp->buffer && (schp->sglist_len > 0)) {
2005                 struct scatterlist *sg = schp->buffer;
2006
2007                 if (schp->dio_in_use) {
2008 #ifdef SG_ALLOW_DIO_CODE
2009                         st_unmap_user_pages(sg, schp->k_use_sg, TRUE);
2010 #endif
2011                 } else {
2012                         int k;
2013
2014                         for (k = 0; (k < schp->k_use_sg) && sg->page;
2015                              ++k, ++sg) {
2016                                 SCSI_LOG_TIMEOUT(5, printk(
2017                                     "sg_remove_scat: k=%d, a=0x%p, len=%d\n",
2018                                     k, sg->page, sg->length));
2019                                 sg_page_free(sg->page, sg->length);
2020                         }
2021                 }
2022                 kfree(schp->buffer);
2023         }
2024         memset(schp, 0, sizeof (*schp));
2025 }
2026
2027 static int
2028 sg_read_xfer(Sg_request * srp)
2029 {
2030         sg_io_hdr_t *hp = &srp->header;
2031         Sg_scatter_hold *schp = &srp->data;
2032         struct scatterlist *sg = schp->buffer;
2033         int num_xfer = 0;
2034         int j, k, onum, usglen, ksglen, res;
2035         int iovec_count = (int) hp->iovec_count;
2036         int dxfer_dir = hp->dxfer_direction;
2037         unsigned char *p;
2038         unsigned char __user *up;
2039         int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
2040
2041         if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_FROM_DEV == dxfer_dir)
2042             || (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
2043                 num_xfer = hp->dxfer_len;
2044                 if (schp->bufflen < num_xfer)
2045                         num_xfer = schp->bufflen;
2046         }
2047         if ((num_xfer <= 0) || (schp->dio_in_use) ||
2048             (new_interface
2049              && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
2050                 return 0;
2051
2052         SCSI_LOG_TIMEOUT(4, printk("sg_read_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
2053                           num_xfer, iovec_count, schp->k_use_sg));
2054         if (iovec_count) {
2055                 onum = iovec_count;
2056                 if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum))
2057                         return -EFAULT;
2058         } else
2059                 onum = 1;
2060
2061         p = page_address(sg->page);
2062         ksglen = sg->length;
2063         for (j = 0, k = 0; j < onum; ++j) {
2064                 res = sg_u_iovec(hp, iovec_count, j, 0, &usglen, &up);
2065                 if (res)
2066                         return res;
2067
2068                 for (; p; ++sg, ksglen = sg->length,
2069                      p = page_address(sg->page)) {
2070                         if (usglen <= 0)
2071                                 break;
2072                         if (ksglen > usglen) {
2073                                 if (usglen >= num_xfer) {
2074                                         if (__copy_to_user(up, p, num_xfer))
2075                                                 return -EFAULT;
2076                                         return 0;
2077                                 }
2078                                 if (__copy_to_user(up, p, usglen))
2079                                         return -EFAULT;
2080                                 p += usglen;
2081                                 ksglen -= usglen;
2082                                 break;
2083                         } else {
2084                                 if (ksglen >= num_xfer) {
2085                                         if (__copy_to_user(up, p, num_xfer))
2086                                                 return -EFAULT;
2087                                         return 0;
2088                                 }
2089                                 if (__copy_to_user(up, p, ksglen))
2090                                         return -EFAULT;
2091                                 up += ksglen;
2092                                 usglen -= ksglen;
2093                         }
2094                         ++k;
2095                         if (k >= schp->k_use_sg)
2096                                 return 0;
2097                 }
2098         }
2099
2100         return 0;
2101 }
2102
2103 static int
2104 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
2105 {
2106         Sg_scatter_hold *schp = &srp->data;
2107         struct scatterlist *sg = schp->buffer;
2108         int k, num;
2109
2110         SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n",
2111                                    num_read_xfer));
2112         if ((!outp) || (num_read_xfer <= 0))
2113                 return 0;
2114
2115         for (k = 0; (k < schp->k_use_sg) && sg->page; ++k, ++sg) {
2116                 num = sg->length;
2117                 if (num > num_read_xfer) {
2118                         if (__copy_to_user(outp, page_address(sg->page),
2119                                            num_read_xfer))
2120                                 return -EFAULT;
2121                         break;
2122                 } else {
2123                         if (__copy_to_user(outp, page_address(sg->page),
2124                                            num))
2125                                 return -EFAULT;
2126                         num_read_xfer -= num;
2127                         if (num_read_xfer <= 0)
2128                                 break;
2129                         outp += num;
2130                 }
2131         }
2132
2133         return 0;
2134 }
2135
2136 static void
2137 sg_build_reserve(Sg_fd * sfp, int req_size)
2138 {
2139         Sg_scatter_hold *schp = &sfp->reserve;
2140
2141         SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
2142         do {
2143                 if (req_size < PAGE_SIZE)
2144                         req_size = PAGE_SIZE;
2145                 if (0 == sg_build_indirect(schp, sfp, req_size))
2146                         return;
2147                 else
2148                         sg_remove_scat(schp);
2149                 req_size >>= 1; /* divide by 2 */
2150         } while (req_size > (PAGE_SIZE / 2));
2151 }
2152
2153 static void
2154 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2155 {
2156         Sg_scatter_hold *req_schp = &srp->data;
2157         Sg_scatter_hold *rsv_schp = &sfp->reserve;
2158         struct scatterlist *sg = rsv_schp->buffer;
2159         int k, num, rem;
2160
2161         srp->res_used = 1;
2162         SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
2163         rem = size;
2164
2165         for (k = 0; k < rsv_schp->k_use_sg; ++k, ++sg) {
2166                 num = sg->length;
2167                 if (rem <= num) {
2168                         sfp->save_scat_len = num;
2169                         sg->length = rem;
2170                         req_schp->k_use_sg = k + 1;
2171                         req_schp->sglist_len = rsv_schp->sglist_len;
2172                         req_schp->buffer = rsv_schp->buffer;
2173
2174                         req_schp->bufflen = size;
2175                         req_schp->b_malloc_len = rsv_schp->b_malloc_len;
2176                         break;
2177                 } else
2178                         rem -= num;
2179         }
2180
2181         if (k >= rsv_schp->k_use_sg)
2182                 SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
2183 }
2184
2185 static void
2186 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2187 {
2188         Sg_scatter_hold *req_schp = &srp->data;
2189         Sg_scatter_hold *rsv_schp = &sfp->reserve;
2190
2191         SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->k_use_sg=%d\n",
2192                                    (int) req_schp->k_use_sg));
2193         if ((rsv_schp->k_use_sg > 0) && (req_schp->k_use_sg > 0)) {
2194                 struct scatterlist *sg = rsv_schp->buffer;
2195
2196                 if (sfp->save_scat_len > 0)
2197                         (sg + (req_schp->k_use_sg - 1))->length =
2198                             (unsigned) sfp->save_scat_len;
2199                 else
2200                         SCSI_LOG_TIMEOUT(1, printk ("sg_unlink_reserve: BAD save_scat_len\n"));
2201         }
2202         req_schp->k_use_sg = 0;
2203         req_schp->bufflen = 0;
2204         req_schp->buffer = NULL;
2205         req_schp->sglist_len = 0;
2206         sfp->save_scat_len = 0;
2207         srp->res_used = 0;
2208 }
2209
2210 static Sg_request *
2211 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2212 {
2213         Sg_request *resp;
2214         unsigned long iflags;
2215
2216         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2217         for (resp = sfp->headrp; resp; resp = resp->nextrp) {
2218                 /* look for requests that are ready + not SG_IO owned */
2219                 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2220                     ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2221                         resp->done = 2; /* guard against other readers */
2222                         break;
2223                 }
2224         }
2225         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2226         return resp;
2227 }
2228
2229 #ifdef CONFIG_SCSI_PROC_FS
2230 static Sg_request *
2231 sg_get_nth_request(Sg_fd * sfp, int nth)
2232 {
2233         Sg_request *resp;
2234         unsigned long iflags;
2235         int k;
2236
2237         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2238         for (k = 0, resp = sfp->headrp; resp && (k < nth);
2239              ++k, resp = resp->nextrp) ;
2240         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2241         return resp;
2242 }
2243 #endif
2244
2245 /* always adds to end of list */
2246 static Sg_request *
2247 sg_add_request(Sg_fd * sfp)
2248 {
2249         int k;
2250         unsigned long iflags;
2251         Sg_request *resp;
2252         Sg_request *rp = sfp->req_arr;
2253
2254         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2255         resp = sfp->headrp;
2256         if (!resp) {
2257                 memset(rp, 0, sizeof (Sg_request));
2258                 rp->parentfp = sfp;
2259                 resp = rp;
2260                 sfp->headrp = resp;
2261         } else {
2262                 if (0 == sfp->cmd_q)
2263                         resp = NULL;    /* command queuing disallowed */
2264                 else {
2265                         for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2266                                 if (!rp->parentfp)
2267                                         break;
2268                         }
2269                         if (k < SG_MAX_QUEUE) {
2270                                 memset(rp, 0, sizeof (Sg_request));
2271                                 rp->parentfp = sfp;
2272                                 while (resp->nextrp)
2273                                         resp = resp->nextrp;
2274                                 resp->nextrp = rp;
2275                                 resp = rp;
2276                         } else
2277                                 resp = NULL;
2278                 }
2279         }
2280         if (resp) {
2281                 resp->nextrp = NULL;
2282                 resp->header.duration = jiffies_to_msecs(jiffies);
2283         }
2284         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2285         return resp;
2286 }
2287
2288 /* Return of 1 for found; 0 for not found */
2289 static int
2290 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2291 {
2292         Sg_request *prev_rp;
2293         Sg_request *rp;
2294         unsigned long iflags;
2295         int res = 0;
2296
2297         if ((!sfp) || (!srp) || (!sfp->headrp))
2298                 return res;
2299         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2300         prev_rp = sfp->headrp;
2301         if (srp == prev_rp) {
2302                 sfp->headrp = prev_rp->nextrp;
2303                 prev_rp->parentfp = NULL;
2304                 res = 1;
2305         } else {
2306                 while ((rp = prev_rp->nextrp)) {
2307                         if (srp == rp) {
2308                                 prev_rp->nextrp = rp->nextrp;
2309                                 rp->parentfp = NULL;
2310                                 res = 1;
2311                                 break;
2312                         }
2313                         prev_rp = rp;
2314                 }
2315         }
2316         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2317         return res;
2318 }
2319
2320 #ifdef CONFIG_SCSI_PROC_FS
2321 static Sg_fd *
2322 sg_get_nth_sfp(Sg_device * sdp, int nth)
2323 {
2324         Sg_fd *resp;
2325         unsigned long iflags;
2326         int k;
2327
2328         read_lock_irqsave(&sg_dev_arr_lock, iflags);
2329         for (k = 0, resp = sdp->headfp; resp && (k < nth);
2330              ++k, resp = resp->nextfp) ;
2331         read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2332         return resp;
2333 }
2334 #endif
2335
2336 static Sg_fd *
2337 sg_add_sfp(Sg_device * sdp, int dev)
2338 {
2339         Sg_fd *sfp;
2340         unsigned long iflags;
2341
2342         sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2343         if (!sfp)
2344                 return NULL;
2345
2346         init_waitqueue_head(&sfp->read_wait);
2347         rwlock_init(&sfp->rq_list_lock);
2348
2349         sfp->timeout = SG_DEFAULT_TIMEOUT;
2350         sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2351         sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2352         sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
2353             sdp->device->host->unchecked_isa_dma : 1;
2354         sfp->cmd_q = SG_DEF_COMMAND_Q;
2355         sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2356         sfp->parentdp = sdp;
2357         write_lock_irqsave(&sg_dev_arr_lock, iflags);
2358         if (!sdp->headfp)
2359                 sdp->headfp = sfp;
2360         else {                  /* add to tail of existing list */
2361                 Sg_fd *pfp = sdp->headfp;
2362                 while (pfp->nextfp)
2363                         pfp = pfp->nextfp;
2364                 pfp->nextfp = sfp;
2365         }
2366         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2367         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));
2368         if (unlikely(sg_big_buff != def_reserved_size))
2369                 sg_big_buff = def_reserved_size;
2370
2371         sg_build_reserve(sfp, sg_big_buff);
2372         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp:   bufflen=%d, k_use_sg=%d\n",
2373                            sfp->reserve.bufflen, sfp->reserve.k_use_sg));
2374         return sfp;
2375 }
2376
2377 static void
2378 __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2379 {
2380         Sg_fd *fp;
2381         Sg_fd *prev_fp;
2382
2383         prev_fp = sdp->headfp;
2384         if (sfp == prev_fp)
2385                 sdp->headfp = prev_fp->nextfp;
2386         else {
2387                 while ((fp = prev_fp->nextfp)) {
2388                         if (sfp == fp) {
2389                                 prev_fp->nextfp = fp->nextfp;
2390                                 break;
2391                         }
2392                         prev_fp = fp;
2393                 }
2394         }
2395         if (sfp->reserve.bufflen > 0) {
2396                 SCSI_LOG_TIMEOUT(6,
2397                         printk("__sg_remove_sfp:    bufflen=%d, k_use_sg=%d\n",
2398                         (int) sfp->reserve.bufflen, (int) sfp->reserve.k_use_sg));
2399                 sg_remove_scat(&sfp->reserve);
2400         }
2401         sfp->parentdp = NULL;
2402         SCSI_LOG_TIMEOUT(6, printk("__sg_remove_sfp:    sfp=0x%p\n", sfp));
2403         kfree(sfp);
2404 }
2405
2406 /* Returns 0 in normal case, 1 when detached and sdp object removed */
2407 static int
2408 sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2409 {
2410         Sg_request *srp;
2411         Sg_request *tsrp;
2412         int dirty = 0;
2413         int res = 0;
2414
2415         for (srp = sfp->headrp; srp; srp = tsrp) {
2416                 tsrp = srp->nextrp;
2417                 if (sg_srp_done(srp, sfp))
2418                         sg_finish_rem_req(srp);
2419                 else
2420                         ++dirty;
2421         }
2422         if (0 == dirty) {
2423                 unsigned long iflags;
2424
2425                 write_lock_irqsave(&sg_dev_arr_lock, iflags);
2426                 __sg_remove_sfp(sdp, sfp);
2427                 if (sdp->detached && (NULL == sdp->headfp)) {
2428                         int k, maxd;
2429
2430                         maxd = sg_dev_max;
2431                         for (k = 0; k < maxd; ++k) {
2432                                 if (sdp == sg_dev_arr[k])
2433                                         break;
2434                         }
2435                         if (k < maxd)
2436                                 sg_dev_arr[k] = NULL;
2437                         kfree((char *) sdp);
2438                         res = 1;
2439                 }
2440                 write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2441         } else {
2442                 /* MOD_INC's to inhibit unloading sg and associated adapter driver */
2443                 /* only bump the access_count if we actually succeeded in
2444                  * throwing another counter on the host module */
2445                 scsi_device_get(sdp->device);   /* XXX: retval ignored? */
2446                 sfp->closed = 1;        /* flag dirty state on this fd */
2447                 SCSI_LOG_TIMEOUT(1, printk("sg_remove_sfp: worrisome, %d writes pending\n",
2448                                   dirty));
2449         }
2450         return res;
2451 }
2452
2453 static int
2454 sg_res_in_use(Sg_fd * sfp)
2455 {
2456         const Sg_request *srp;
2457         unsigned long iflags;
2458
2459         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2460         for (srp = sfp->headrp; srp; srp = srp->nextrp)
2461                 if (srp->res_used)
2462                         break;
2463         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2464         return srp ? 1 : 0;
2465 }
2466
2467 /* The size fetched (value output via retSzp) set when non-NULL return */
2468 static struct page *
2469 sg_page_malloc(int rqSz, int lowDma, int *retSzp)
2470 {
2471         struct page *resp = NULL;
2472         gfp_t page_mask;
2473         int order, a_size;
2474         int resSz;
2475
2476         if ((rqSz <= 0) || (NULL == retSzp))
2477                 return resp;
2478
2479         if (lowDma)
2480                 page_mask = GFP_ATOMIC | GFP_DMA | __GFP_COMP | __GFP_NOWARN;
2481         else
2482                 page_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
2483
2484         for (order = 0, a_size = PAGE_SIZE; a_size < rqSz;
2485              order++, a_size <<= 1) ;
2486         resSz = a_size;         /* rounded up if necessary */
2487         resp = alloc_pages(page_mask, order);
2488         while ((!resp) && order) {
2489                 --order;
2490                 a_size >>= 1;   /* divide by 2, until PAGE_SIZE */
2491                 resp =  alloc_pages(page_mask, order);  /* try half */
2492                 resSz = a_size;
2493         }
2494         if (resp) {
2495                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2496                         memset(page_address(resp), 0, resSz);
2497                 *retSzp = resSz;
2498         }
2499         return resp;
2500 }
2501
2502 static void
2503 sg_page_free(struct page *page, int size)
2504 {
2505         int order, a_size;
2506
2507         if (!page)
2508                 return;
2509         for (order = 0, a_size = PAGE_SIZE; a_size < size;
2510              order++, a_size <<= 1) ;
2511         __free_pages(page, order);
2512 }
2513
2514 #ifndef MAINTENANCE_IN_CMD
2515 #define MAINTENANCE_IN_CMD 0xa3
2516 #endif
2517
2518 static unsigned char allow_ops[] = { TEST_UNIT_READY, REQUEST_SENSE,
2519         INQUIRY, READ_CAPACITY, READ_BUFFER, READ_6, READ_10, READ_12,
2520         READ_16, MODE_SENSE, MODE_SENSE_10, LOG_SENSE, REPORT_LUNS,
2521         SERVICE_ACTION_IN, RECEIVE_DIAGNOSTIC, READ_LONG, MAINTENANCE_IN_CMD
2522 };
2523
2524 static int
2525 sg_allow_access(unsigned char opcode, char dev_type)
2526 {
2527         int k;
2528
2529         if (TYPE_SCANNER == dev_type)   /* TYPE_ROM maybe burner */
2530                 return 1;
2531         for (k = 0; k < sizeof (allow_ops); ++k) {
2532                 if (opcode == allow_ops[k])
2533                         return 1;
2534         }
2535         return 0;
2536 }
2537
2538 #ifdef CONFIG_SCSI_PROC_FS
2539 static int
2540 sg_last_dev(void)
2541 {
2542         int k;
2543         unsigned long iflags;
2544
2545         read_lock_irqsave(&sg_dev_arr_lock, iflags);
2546         for (k = sg_dev_max - 1; k >= 0; --k)
2547                 if (sg_dev_arr[k] && sg_dev_arr[k]->device)
2548                         break;
2549         read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2550         return k + 1;           /* origin 1 */
2551 }
2552 #endif
2553
2554 static Sg_device *
2555 sg_get_dev(int dev)
2556 {
2557         Sg_device *sdp = NULL;
2558         unsigned long iflags;
2559
2560         if (sg_dev_arr && (dev >= 0)) {
2561                 read_lock_irqsave(&sg_dev_arr_lock, iflags);
2562                 if (dev < sg_dev_max)
2563                         sdp = sg_dev_arr[dev];
2564                 read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2565         }
2566         return sdp;
2567 }
2568
2569 #ifdef CONFIG_SCSI_PROC_FS
2570
2571 static struct proc_dir_entry *sg_proc_sgp = NULL;
2572
2573 static char sg_proc_sg_dirname[] = "scsi/sg";
2574
2575 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2576
2577 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2578 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2579                                   size_t count, loff_t *off);
2580 static struct file_operations adio_fops = {
2581         /* .owner, .read and .llseek added in sg_proc_init() */
2582         .open = sg_proc_single_open_adio,
2583         .write = sg_proc_write_adio,
2584         .release = single_release,
2585 };
2586
2587 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2588 static ssize_t sg_proc_write_dressz(struct file *filp,
2589                 const char __user *buffer, size_t count, loff_t *off);
2590 static struct file_operations dressz_fops = {
2591         .open = sg_proc_single_open_dressz,
2592         .write = sg_proc_write_dressz,
2593         .release = single_release,
2594 };
2595
2596 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2597 static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2598 static struct file_operations version_fops = {
2599         .open = sg_proc_single_open_version,
2600         .release = single_release,
2601 };
2602
2603 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2604 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2605 static struct file_operations devhdr_fops = {
2606         .open = sg_proc_single_open_devhdr,
2607         .release = single_release,
2608 };
2609
2610 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2611 static int sg_proc_open_dev(struct inode *inode, struct file *file);
2612 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2613 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2614 static void dev_seq_stop(struct seq_file *s, void *v);
2615 static struct file_operations dev_fops = {
2616         .open = sg_proc_open_dev,
2617         .release = seq_release,
2618 };
2619 static struct seq_operations dev_seq_ops = {
2620         .start = dev_seq_start,
2621         .next  = dev_seq_next,
2622         .stop  = dev_seq_stop,
2623         .show  = sg_proc_seq_show_dev,
2624 };
2625
2626 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2627 static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2628 static struct file_operations devstrs_fops = {
2629         .open = sg_proc_open_devstrs,
2630         .release = seq_release,
2631 };
2632 static struct seq_operations devstrs_seq_ops = {
2633         .start = dev_seq_start,
2634         .next  = dev_seq_next,
2635         .stop  = dev_seq_stop,
2636         .show  = sg_proc_seq_show_devstrs,
2637 };
2638
2639 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2640 static int sg_proc_open_debug(struct inode *inode, struct file *file);
2641 static struct file_operations debug_fops = {
2642         .open = sg_proc_open_debug,
2643         .release = seq_release,
2644 };
2645 static struct seq_operations debug_seq_ops = {
2646         .start = dev_seq_start,
2647         .next  = dev_seq_next,
2648         .stop  = dev_seq_stop,
2649         .show  = sg_proc_seq_show_debug,
2650 };
2651
2652
2653 struct sg_proc_leaf {
2654         const char * name;
2655         struct file_operations * fops;
2656 };
2657
2658 static struct sg_proc_leaf sg_proc_leaf_arr[] = {
2659         {"allow_dio", &adio_fops},
2660         {"debug", &debug_fops},
2661         {"def_reserved_size", &dressz_fops},
2662         {"device_hdr", &devhdr_fops},
2663         {"devices", &dev_fops},
2664         {"device_strs", &devstrs_fops},
2665         {"version", &version_fops}
2666 };
2667
2668 static int
2669 sg_proc_init(void)
2670 {
2671         int k, mask;
2672         int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2673         struct proc_dir_entry *pdep;
2674         struct sg_proc_leaf * leaf;
2675
2676         sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2677         if (!sg_proc_sgp)
2678                 return 1;
2679         for (k = 0; k < num_leaves; ++k) {
2680                 leaf = &sg_proc_leaf_arr[k];
2681                 mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2682                 pdep = create_proc_entry(leaf->name, mask, sg_proc_sgp);
2683                 if (pdep) {
2684                         leaf->fops->owner = THIS_MODULE,
2685                         leaf->fops->read = seq_read,
2686                         leaf->fops->llseek = seq_lseek,
2687                         pdep->proc_fops = leaf->fops;
2688                 }
2689         }
2690         return 0;
2691 }
2692
2693 static void
2694 sg_proc_cleanup(void)
2695 {
2696         int k;
2697         int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2698
2699         if (!sg_proc_sgp)
2700                 return;
2701         for (k = 0; k < num_leaves; ++k)
2702                 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2703         remove_proc_entry(sg_proc_sg_dirname, NULL);
2704 }
2705
2706
2707 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2708 {
2709         seq_printf(s, "%d\n", *((int *)s->private));
2710         return 0;
2711 }
2712
2713 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2714 {
2715         return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2716 }
2717
2718 static ssize_t
2719 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2720                    size_t count, loff_t *off)
2721 {
2722         int num;
2723         char buff[11];
2724
2725         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2726                 return -EACCES;
2727         num = (count < 10) ? count : 10;
2728         if (copy_from_user(buff, buffer, num))
2729                 return -EFAULT;
2730         buff[num] = '\0';
2731         sg_allow_dio = simple_strtoul(buff, NULL, 10) ? 1 : 0;
2732         return count;
2733 }
2734
2735 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2736 {
2737         return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2738 }
2739
2740 static ssize_t
2741 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2742                      size_t count, loff_t *off)
2743 {
2744         int num;
2745         unsigned long k = ULONG_MAX;
2746         char buff[11];
2747
2748         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2749                 return -EACCES;
2750         num = (count < 10) ? count : 10;
2751         if (copy_from_user(buff, buffer, num))
2752                 return -EFAULT;
2753         buff[num] = '\0';
2754         k = simple_strtoul(buff, NULL, 10);
2755         if (k <= 1048576) {     /* limit "big buff" to 1 MB */
2756                 sg_big_buff = k;
2757                 return count;
2758         }
2759         return -ERANGE;
2760 }
2761
2762 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2763 {
2764         seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2765                    sg_version_date);
2766         return 0;
2767 }
2768
2769 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2770 {
2771         return single_open(file, sg_proc_seq_show_version, NULL);
2772 }
2773
2774 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2775 {
2776         seq_printf(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\t"
2777                    "online\n");
2778         return 0;
2779 }
2780
2781 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2782 {
2783         return single_open(file, sg_proc_seq_show_devhdr, NULL);
2784 }
2785
2786 struct sg_proc_deviter {
2787         loff_t  index;
2788         size_t  max;
2789 };
2790
2791 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2792 {
2793         struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2794
2795         s->private = it;
2796         if (! it)
2797                 return NULL;
2798
2799         if (NULL == sg_dev_arr)
2800                 return NULL;
2801         it->index = *pos;
2802         it->max = sg_last_dev();
2803         if (it->index >= it->max)
2804                 return NULL;
2805         return it;
2806 }
2807
2808 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2809 {
2810         struct sg_proc_deviter * it = s->private;
2811
2812         *pos = ++it->index;
2813         return (it->index < it->max) ? it : NULL;
2814 }
2815
2816 static void dev_seq_stop(struct seq_file *s, void *v)
2817 {
2818         kfree(s->private);
2819 }
2820
2821 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2822 {
2823         return seq_open(file, &dev_seq_ops);
2824 }
2825
2826 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2827 {
2828         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2829         Sg_device *sdp;
2830         struct scsi_device *scsidp;
2831
2832         sdp = it ? sg_get_dev(it->index) : NULL;
2833         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2834                 seq_printf(s, "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n",
2835                               scsidp->host->host_no, scsidp->channel,
2836                               scsidp->id, scsidp->lun, (int) scsidp->type,
2837                               1,
2838                               (int) scsidp->queue_depth,
2839                               (int) scsidp->device_busy,
2840                               (int) scsi_device_online(scsidp));
2841         else
2842                 seq_printf(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2843         return 0;
2844 }
2845
2846 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2847 {
2848         return seq_open(file, &devstrs_seq_ops);
2849 }
2850
2851 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2852 {
2853         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2854         Sg_device *sdp;
2855         struct scsi_device *scsidp;
2856
2857         sdp = it ? sg_get_dev(it->index) : NULL;
2858         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2859                 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2860                            scsidp->vendor, scsidp->model, scsidp->rev);
2861         else
2862                 seq_printf(s, "<no active device>\n");
2863         return 0;
2864 }
2865
2866 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2867 {
2868         int k, m, new_interface, blen, usg;
2869         Sg_request *srp;
2870         Sg_fd *fp;
2871         const sg_io_hdr_t *hp;
2872         const char * cp;
2873         unsigned int ms;
2874
2875         for (k = 0; (fp = sg_get_nth_sfp(sdp, k)); ++k) {
2876                 seq_printf(s, "   FD(%d): timeout=%dms bufflen=%d "
2877                            "(res)sgat=%d low_dma=%d\n", k + 1,
2878                            jiffies_to_msecs(fp->timeout),
2879                            fp->reserve.bufflen,
2880                            (int) fp->reserve.k_use_sg,
2881                            (int) fp->low_dma);
2882                 seq_printf(s, "   cmd_q=%d f_packid=%d k_orphan=%d closed=%d\n",
2883                            (int) fp->cmd_q, (int) fp->force_packid,
2884                            (int) fp->keep_orphan, (int) fp->closed);
2885                 for (m = 0; (srp = sg_get_nth_request(fp, m)); ++m) {
2886                         hp = &srp->header;
2887                         new_interface = (hp->interface_id == '\0') ? 0 : 1;
2888                         if (srp->res_used) {
2889                                 if (new_interface &&
2890                                     (SG_FLAG_MMAP_IO & hp->flags))
2891                                         cp = "     mmap>> ";
2892                                 else
2893                                         cp = "     rb>> ";
2894                         } else {
2895                                 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2896                                         cp = "     dio>> ";
2897                                 else
2898                                         cp = "     ";
2899                         }
2900                         seq_printf(s, cp);
2901                         blen = srp->data.bufflen;
2902                         usg = srp->data.k_use_sg;
2903                         seq_printf(s, srp->done ?
2904                                    ((1 == srp->done) ?  "rcv:" : "fin:")
2905                                    : "act:");
2906                         seq_printf(s, " id=%d blen=%d",
2907                                    srp->header.pack_id, blen);
2908                         if (srp->done)
2909                                 seq_printf(s, " dur=%d", hp->duration);
2910                         else {
2911                                 ms = jiffies_to_msecs(jiffies);
2912                                 seq_printf(s, " t_o/elap=%d/%d",
2913                                         (new_interface ? hp->timeout :
2914                                                   jiffies_to_msecs(fp->timeout)),
2915                                         (ms > hp->duration ? ms - hp->duration : 0));
2916                         }
2917                         seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2918                                    (int) srp->data.cmd_opcode);
2919                 }
2920                 if (0 == m)
2921                         seq_printf(s, "     No requests active\n");
2922         }
2923 }
2924
2925 static int sg_proc_open_debug(struct inode *inode, struct file *file)
2926 {
2927         return seq_open(file, &debug_seq_ops);
2928 }
2929
2930 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2931 {
2932         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2933         Sg_device *sdp;
2934
2935         if (it && (0 == it->index)) {
2936                 seq_printf(s, "dev_max(currently)=%d max_active_device=%d "
2937                            "(origin 1)\n", sg_dev_max, (int)it->max);
2938                 seq_printf(s, " def_reserved_size=%d\n", sg_big_buff);
2939         }
2940         sdp = it ? sg_get_dev(it->index) : NULL;
2941         if (sdp) {
2942                 struct scsi_device *scsidp = sdp->device;
2943
2944                 if (NULL == scsidp) {
2945                         seq_printf(s, "device %d detached ??\n",
2946                                    (int)it->index);
2947                         return 0;
2948                 }
2949
2950                 if (sg_get_nth_sfp(sdp, 0)) {
2951                         seq_printf(s, " >>> device=%s ",
2952                                 sdp->disk->disk_name);
2953                         if (sdp->detached)
2954                                 seq_printf(s, "detached pending close ");
2955                         else
2956                                 seq_printf
2957                                     (s, "scsi%d chan=%d id=%d lun=%d   em=%d",
2958                                      scsidp->host->host_no,
2959                                      scsidp->channel, scsidp->id,
2960                                      scsidp->lun,
2961                                      scsidp->host->hostt->emulated);
2962                         seq_printf(s, " sg_tablesize=%d excl=%d\n",
2963                                    sdp->sg_tablesize, sdp->exclude);
2964                 }
2965                 sg_proc_debug_helper(s, sdp);
2966         }
2967         return 0;
2968 }
2969
2970 #endif                          /* CONFIG_SCSI_PROC_FS */
2971
2972 module_init(init_sg);
2973 module_exit(exit_sg);