err.no Git - 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/moduleparam.h>
  45 #include <linux/cdev.h>
  46 #include <linux/idr.h>
  47 #include <linux/seq_file.h>
  48 #include <linux/blkdev.h>
  49 #include <linux/delay.h>
  50 #include <linux/scatterlist.h>
  51 #include <linux/blktrace_api.h>
  52
  53 #include "scsi.h"
  54 #include <scsi/scsi_dbg.h>
  55 #include <scsi/scsi_host.h>
  56 #include <scsi/scsi_driver.h>
  57 #include <scsi/scsi_ioctl.h>
  58 #include <scsi/sg.h>
  59
  60 #include "scsi_logging.h"
  61
  62 #ifdef CONFIG_SCSI_PROC_FS
  63 #include <linux/proc_fs.h>
  64 static char *sg_version_date = "20061027";
  65
  66 static int sg_proc_init(void);
  67 static void sg_proc_cleanup(void);
  68 #endif
  69
  70 #define SG_ALLOW_DIO_DEF 0
  71 #define SG_ALLOW_DIO_CODE /* compile out by commenting this define */
  72
  73 #define SG_MAX_DEVS 32768
  74
  75 /*
  76  * Suppose you want to calculate the formula muldiv(x,m,d)=int(x * m / d)
  77  * Then when using 32 bit integers x * m may overflow during the calculation.
  78  * Replacing muldiv(x) by muldiv(x)=((x % d) * m) / d + int(x / d) * m
  79  * calculates the same, but prevents the overflow when both m and d
  80  * are "small" numbers (like HZ and USER_HZ).
  81  * Of course an overflow is inavoidable if the result of muldiv doesn't fit
  82  * in 32 bits.
  83  */
  84 #define MULDIV(X,MUL,DIV) ((((X % DIV) * MUL) / DIV) + ((X / DIV) * MUL))
  85
  86 #define SG_DEFAULT_TIMEOUT MULDIV(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
  87
  88 int sg_big_buff = SG_DEF_RESERVED_SIZE;
  89 /* N.B. This variable is readable and writeable via
  90    /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
  91    of this size (or less if there is not enough memory) will be reserved
  92    for use by this file descriptor. [Deprecated usage: this variable is also
  93    readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
  94    the kernel (i.e. it is not a module).] */
  95 static int def_reserved_size = -1;      /* picks up init parameter */
  96 static int sg_allow_dio = SG_ALLOW_DIO_DEF;
  97
  98 static int scatter_elem_sz = SG_SCATTER_SZ;
  99 static int scatter_elem_sz_prev = SG_SCATTER_SZ;
 100
 101 #define SG_SECTOR_SZ 512
 102 #define SG_SECTOR_MSK (SG_SECTOR_SZ - 1)
 103
 104 static int sg_add(struct device *, struct class_interface *);
 105 static void sg_remove(struct device *, struct class_interface *);
 106
 107 static DEFINE_IDR(sg_index_idr);
 108 static DEFINE_RWLOCK(sg_index_lock);    /* Also used to lock
 109                                                            file descriptor list for device */
 110
 111 static struct class_interface sg_interface = {
 112         .add_dev        = sg_add,
 113         .remove_dev     = 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 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         u32 index;              /* device index number */
 167         Sg_fd *headfp;          /* first open fd belonging to this device */
 168         volatile char detached; /* 0->attached, 1->detached pending removal */
 169         volatile char exclude;  /* opened for exclusive access */
 170         char sgdebug;           /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
 171         struct gendisk *disk;
 172         struct cdev * cdev;     /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
 173 } Sg_device;
 174
 175 static int sg_fasync(int fd, struct file *filp, int mode);
 176 /* tasklet or soft irq callback */
 177 static void sg_cmd_done(void *data, char *sense, int result, int resid);
 178 static int sg_start_req(Sg_request * srp);
 179 static void sg_finish_rem_req(Sg_request * srp);
 180 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
 181 static int sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp,
 182                          int tablesize);
 183 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
 184                            Sg_request * srp);
 185 static ssize_t sg_new_write(Sg_fd * sfp, const char __user *buf, size_t count,
 186                             int blocking, int read_only, Sg_request ** o_srp);
 187 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
 188                            unsigned char *cmnd, int timeout, int blocking);
 189 static int sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
 190                       int wr_xf, int *countp, unsigned char __user **up);
 191 static int sg_write_xfer(Sg_request * srp);
 192 static int sg_read_xfer(Sg_request * srp);
 193 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
 194 static void sg_remove_scat(Sg_scatter_hold * schp);
 195 static void sg_build_reserve(Sg_fd * sfp, int req_size);
 196 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
 197 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
 198 static struct page *sg_page_malloc(int rqSz, int lowDma, int *retSzp);
 199 static void sg_page_free(struct page *page, int size);
 200 static Sg_fd *sg_add_sfp(Sg_device * sdp, int dev);
 201 static int sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
 202 static void __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
 203 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
 204 static Sg_request *sg_add_request(Sg_fd * sfp);
 205 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
 206 static int sg_res_in_use(Sg_fd * sfp);
 207 static int sg_allow_access(unsigned char opcode, char dev_type);
 208 static int sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len);
 209 static Sg_device *sg_get_dev(int dev);
 210 #ifdef CONFIG_SCSI_PROC_FS
 211 static int sg_last_dev(void);
 212 #endif
 213
 214 #define SZ_SG_HEADER sizeof(struct sg_header)
 215 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
 216 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
 217 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
 218
 219 static int
 220 sg_open(struct inode *inode, struct file *filp)
 221 {
 222         int dev = iminor(inode);
 223         int flags = filp->f_flags;
 224         struct request_queue *q;
 225         Sg_device *sdp;
 226         Sg_fd *sfp;
 227         int res;
 228         int retval;
 229
 230         nonseekable_open(inode, filp);
 231         SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags));
 232         sdp = sg_get_dev(dev);
 233         if ((!sdp) || (!sdp->device))
 234                 return -ENXIO;
 235         if (sdp->detached)
 236                 return -ENODEV;
 237
 238         /* This driver's module count bumped by fops_get in <linux/fs.h> */
 239         /* Prevent the device driver from vanishing while we sleep */
 240         retval = scsi_device_get(sdp->device);
 241         if (retval)
 242                 return retval;
 243
 244         if (!((flags & O_NONBLOCK) ||
 245               scsi_block_when_processing_errors(sdp->device))) {
 246                 retval = -ENXIO;
 247                 /* we are in error recovery for this device */
 248                 goto error_out;
 249         }
 250
 251         if (flags & O_EXCL) {
 252                 if (O_RDONLY == (flags & O_ACCMODE)) {
 253                         retval = -EPERM; /* Can't lock it with read only access */
 254                         goto error_out;
 255                 }
 256                 if (sdp->headfp && (flags & O_NONBLOCK)) {
 257                         retval = -EBUSY;
 258                         goto error_out;
 259                 }
 260                 res = 0;
 261                 __wait_event_interruptible(sdp->o_excl_wait,
 262                         ((sdp->headfp || sdp->exclude) ? 0 : (sdp->exclude = 1)), res);
 263                 if (res) {
 264                         retval = res;   /* -ERESTARTSYS because signal hit process */
 265                         goto error_out;
 266                 }
 267         } else if (sdp->exclude) {      /* some other fd has an exclusive lock on dev */
 268                 if (flags & O_NONBLOCK) {
 269                         retval = -EBUSY;
 270                         goto error_out;
 271                 }
 272                 res = 0;
 273                 __wait_event_interruptible(sdp->o_excl_wait, (!sdp->exclude),
 274                                            res);
 275                 if (res) {
 276                         retval = res;   /* -ERESTARTSYS because signal hit process */
 277                         goto error_out;
 278                 }
 279         }
 280         if (sdp->detached) {
 281                 retval = -ENODEV;
 282                 goto error_out;
 283         }
 284         if (!sdp->headfp) {     /* no existing opens on this device */
 285                 sdp->sgdebug = 0;
 286                 q = sdp->device->request_queue;
 287                 sdp->sg_tablesize = min(q->max_hw_segments,
 288                                         q->max_phys_segments);
 289         }
 290         if ((sfp = sg_add_sfp(sdp, dev)))
 291                 filp->private_data = sfp;
 292         else {
 293                 if (flags & O_EXCL)
 294                         sdp->exclude = 0;       /* undo if error */
 295                 retval = -ENOMEM;
 296                 goto error_out;
 297         }
 298         return 0;
 299
 300       error_out:
 301         scsi_device_put(sdp->device);
 302         return retval;
 303 }
 304
 305 /* Following function was formerly called 'sg_close' */
 306 static int
 307 sg_release(struct inode *inode, struct file *filp)
 308 {
 309         Sg_device *sdp;
 310         Sg_fd *sfp;
 311
 312         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 313                 return -ENXIO;
 314         SCSI_LOG_TIMEOUT(3, printk("sg_release: %s\n", sdp->disk->disk_name));
 315         sg_fasync(-1, filp, 0); /* remove filp from async notification list */
 316         if (0 == sg_remove_sfp(sdp, sfp)) {     /* Returns 1 when sdp gone */
 317                 if (!sdp->detached) {
 318                         scsi_device_put(sdp->device);
 319                 }
 320                 sdp->exclude = 0;
 321                 wake_up_interruptible(&sdp->o_excl_wait);
 322         }
 323         return 0;
 324 }
 325
 326 static ssize_t
 327 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
 328 {
 329         Sg_device *sdp;
 330         Sg_fd *sfp;
 331         Sg_request *srp;
 332         int req_pack_id = -1;
 333         sg_io_hdr_t *hp;
 334         struct sg_header *old_hdr = NULL;
 335         int retval = 0;
 336
 337         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 338                 return -ENXIO;
 339         SCSI_LOG_TIMEOUT(3, printk("sg_read: %s, count=%d\n",
 340                                    sdp->disk->disk_name, (int) count));
 341
 342         if (!access_ok(VERIFY_WRITE, buf, count))
 343                 return -EFAULT;
 344         if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
 345                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 346                 if (!old_hdr)
 347                         return -ENOMEM;
 348                 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
 349                         retval = -EFAULT;
 350                         goto free_old_hdr;
 351                 }
 352                 if (old_hdr->reply_len < 0) {
 353                         if (count >= SZ_SG_IO_HDR) {
 354                                 sg_io_hdr_t *new_hdr;
 355                                 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
 356                                 if (!new_hdr) {
 357                                         retval = -ENOMEM;
 358                                         goto free_old_hdr;
 359                                 }
 360                                 retval =__copy_from_user
 361                                     (new_hdr, buf, SZ_SG_IO_HDR);
 362                                 req_pack_id = new_hdr->pack_id;
 363                                 kfree(new_hdr);
 364                                 if (retval) {
 365                                         retval = -EFAULT;
 366                                         goto free_old_hdr;
 367                                 }
 368                         }
 369                 } else
 370                         req_pack_id = old_hdr->pack_id;
 371         }
 372         srp = sg_get_rq_mark(sfp, req_pack_id);
 373         if (!srp) {             /* now wait on packet to arrive */
 374                 if (sdp->detached) {
 375                         retval = -ENODEV;
 376                         goto free_old_hdr;
 377                 }
 378                 if (filp->f_flags & O_NONBLOCK) {
 379                         retval = -EAGAIN;
 380                         goto free_old_hdr;
 381                 }
 382                 while (1) {
 383                         retval = 0; /* following macro beats race condition */
 384                         __wait_event_interruptible(sfp->read_wait,
 385                                 (sdp->detached ||
 386                                 (srp = sg_get_rq_mark(sfp, req_pack_id))),
 387                                 retval);
 388                         if (sdp->detached) {
 389                                 retval = -ENODEV;
 390                                 goto free_old_hdr;
 391                         }
 392                         if (0 == retval)
 393                                 break;
 394
 395                         /* -ERESTARTSYS as signal hit process */
 396                         goto free_old_hdr;
 397                 }
 398         }
 399         if (srp->header.interface_id != '\0') {
 400                 retval = sg_new_read(sfp, buf, count, srp);
 401                 goto free_old_hdr;
 402         }
 403
 404         hp = &srp->header;
 405         if (old_hdr == NULL) {
 406                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 407                 if (! old_hdr) {
 408                         retval = -ENOMEM;
 409                         goto free_old_hdr;
 410                 }
 411         }
 412         memset(old_hdr, 0, SZ_SG_HEADER);
 413         old_hdr->reply_len = (int) hp->timeout;
 414         old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
 415         old_hdr->pack_id = hp->pack_id;
 416         old_hdr->twelve_byte =
 417             ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
 418         old_hdr->target_status = hp->masked_status;
 419         old_hdr->host_status = hp->host_status;
 420         old_hdr->driver_status = hp->driver_status;
 421         if ((CHECK_CONDITION & hp->masked_status) ||
 422             (DRIVER_SENSE & hp->driver_status))
 423                 memcpy(old_hdr->sense_buffer, srp->sense_b,
 424                        sizeof (old_hdr->sense_buffer));
 425         switch (hp->host_status) {
 426         /* This setup of 'result' is for backward compatibility and is best
 427            ignored by the user who should use target, host + driver status */
 428         case DID_OK:
 429         case DID_PASSTHROUGH:
 430         case DID_SOFT_ERROR:
 431                 old_hdr->result = 0;
 432                 break;
 433         case DID_NO_CONNECT:
 434         case DID_BUS_BUSY:
 435         case DID_TIME_OUT:
 436                 old_hdr->result = EBUSY;
 437                 break;
 438         case DID_BAD_TARGET:
 439         case DID_ABORT:
 440         case DID_PARITY:
 441         case DID_RESET:
 442         case DID_BAD_INTR:
 443                 old_hdr->result = EIO;
 444                 break;
 445         case DID_ERROR:
 446                 old_hdr->result = (srp->sense_b[0] == 0 &&
 447                                   hp->masked_status == GOOD) ? 0 : EIO;
 448                 break;
 449         default:
 450                 old_hdr->result = EIO;
 451                 break;
 452         }
 453
 454         /* Now copy the result back to the user buffer.  */
 455         if (count >= SZ_SG_HEADER) {
 456                 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
 457                         retval = -EFAULT;
 458                         goto free_old_hdr;
 459                 }
 460                 buf += SZ_SG_HEADER;
 461                 if (count > old_hdr->reply_len)
 462                         count = old_hdr->reply_len;
 463                 if (count > SZ_SG_HEADER) {
 464                         if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
 465                                 retval = -EFAULT;
 466                                 goto free_old_hdr;
 467                         }
 468                 }
 469         } else
 470                 count = (old_hdr->result == 0) ? 0 : -EIO;
 471         sg_finish_rem_req(srp);
 472         retval = count;
 473 free_old_hdr:
 474         kfree(old_hdr);
 475         return retval;
 476 }
 477
 478 static ssize_t
 479 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
 480 {
 481         sg_io_hdr_t *hp = &srp->header;
 482         int err = 0;
 483         int len;
 484
 485         if (count < SZ_SG_IO_HDR) {
 486                 err = -EINVAL;
 487                 goto err_out;
 488         }
 489         hp->sb_len_wr = 0;
 490         if ((hp->mx_sb_len > 0) && hp->sbp) {
 491                 if ((CHECK_CONDITION & hp->masked_status) ||
 492                     (DRIVER_SENSE & hp->driver_status)) {
 493                         int sb_len = SCSI_SENSE_BUFFERSIZE;
 494                         sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
 495                         len = 8 + (int) srp->sense_b[7];        /* Additional sense length field */
 496                         len = (len > sb_len) ? sb_len : len;
 497                         if (copy_to_user(hp->sbp, srp->sense_b, len)) {
 498                                 err = -EFAULT;
 499                                 goto err_out;
 500                         }
 501                         hp->sb_len_wr = len;
 502                 }
 503         }
 504         if (hp->masked_status || hp->host_status || hp->driver_status)
 505                 hp->info |= SG_INFO_CHECK;
 506         if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
 507                 err = -EFAULT;
 508                 goto err_out;
 509         }
 510         err = sg_read_xfer(srp);
 511       err_out:
 512         sg_finish_rem_req(srp);
 513         return (0 == err) ? count : err;
 514 }
 515
 516 static ssize_t
 517 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
 518 {
 519         int mxsize, cmd_size, k;
 520         int input_size, blocking;
 521         unsigned char opcode;
 522         Sg_device *sdp;
 523         Sg_fd *sfp;
 524         Sg_request *srp;
 525         struct sg_header old_hdr;
 526         sg_io_hdr_t *hp;
 527         unsigned char cmnd[MAX_COMMAND_SIZE];
 528
 529         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 530                 return -ENXIO;
 531         SCSI_LOG_TIMEOUT(3, printk("sg_write: %s, count=%d\n",
 532                                    sdp->disk->disk_name, (int) count));
 533         if (sdp->detached)
 534                 return -ENODEV;
 535         if (!((filp->f_flags & O_NONBLOCK) ||
 536               scsi_block_when_processing_errors(sdp->device)))
 537                 return -ENXIO;
 538
 539         if (!access_ok(VERIFY_READ, buf, count))
 540                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 541         if (count < SZ_SG_HEADER)
 542                 return -EIO;
 543         if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
 544                 return -EFAULT;
 545         blocking = !(filp->f_flags & O_NONBLOCK);
 546         if (old_hdr.reply_len < 0)
 547                 return sg_new_write(sfp, buf, count, blocking, 0, NULL);
 548         if (count < (SZ_SG_HEADER + 6))
 549                 return -EIO;    /* The minimum scsi command length is 6 bytes. */
 550
 551         if (!(srp = sg_add_request(sfp))) {
 552                 SCSI_LOG_TIMEOUT(1, printk("sg_write: queue full\n"));
 553                 return -EDOM;
 554         }
 555         buf += SZ_SG_HEADER;
 556         __get_user(opcode, buf);
 557         if (sfp->next_cmd_len > 0) {
 558                 if (sfp->next_cmd_len > MAX_COMMAND_SIZE) {
 559                         SCSI_LOG_TIMEOUT(1, printk("sg_write: command length too long\n"));
 560                         sfp->next_cmd_len = 0;
 561                         sg_remove_request(sfp, srp);
 562                         return -EIO;
 563                 }
 564                 cmd_size = sfp->next_cmd_len;
 565                 sfp->next_cmd_len = 0;  /* reset so only this write() effected */
 566         } else {
 567                 cmd_size = COMMAND_SIZE(opcode);        /* based on SCSI command group */
 568                 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
 569                         cmd_size = 12;
 570         }
 571         SCSI_LOG_TIMEOUT(4, printk(
 572                 "sg_write:   scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
 573 /* Determine buffer size.  */
 574         input_size = count - cmd_size;
 575         mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
 576         mxsize -= SZ_SG_HEADER;
 577         input_size -= SZ_SG_HEADER;
 578         if (input_size < 0) {
 579                 sg_remove_request(sfp, srp);
 580                 return -EIO;    /* User did not pass enough bytes for this command. */
 581         }
 582         hp = &srp->header;
 583         hp->interface_id = '\0';        /* indicator of old interface tunnelled */
 584         hp->cmd_len = (unsigned char) cmd_size;
 585         hp->iovec_count = 0;
 586         hp->mx_sb_len = 0;
 587         if (input_size > 0)
 588                 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
 589                     SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
 590         else
 591                 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
 592         hp->dxfer_len = mxsize;
 593         hp->dxferp = (char __user *)buf + cmd_size;
 594         hp->sbp = NULL;
 595         hp->timeout = old_hdr.reply_len;        /* structure abuse ... */
 596         hp->flags = input_size; /* structure abuse ... */
 597         hp->pack_id = old_hdr.pack_id;
 598         hp->usr_ptr = NULL;
 599         if (__copy_from_user(cmnd, buf, cmd_size))
 600                 return -EFAULT;
 601         /*
 602          * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
 603          * but is is possible that the app intended SG_DXFER_TO_DEV, because there
 604          * is a non-zero input_size, so emit a warning.
 605          */
 606         if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
 607                 static char cmd[TASK_COMM_LEN];
 608                 if (strcmp(current->comm, cmd) && printk_ratelimit()) {
 609                         printk(KERN_WARNING
 610                                "sg_write: data in/out %d/%d bytes for SCSI command 0x%x--"
 611                                "guessing data in;\n" KERN_WARNING "   "
 612                                "program %s not setting count and/or reply_len properly\n",
 613                                old_hdr.reply_len - (int)SZ_SG_HEADER,
 614                                input_size, (unsigned int) cmnd[0],
 615                                current->comm);
 616                         strcpy(cmd, current->comm);
 617                 }
 618         }
 619         k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
 620         return (k < 0) ? k : count;
 621 }
 622
 623 static ssize_t
 624 sg_new_write(Sg_fd * sfp, const char __user *buf, size_t count,
 625              int blocking, int read_only, Sg_request ** o_srp)
 626 {
 627         int k;
 628         Sg_request *srp;
 629         sg_io_hdr_t *hp;
 630         unsigned char cmnd[MAX_COMMAND_SIZE];
 631         int timeout;
 632         unsigned long ul_timeout;
 633
 634         if (count < SZ_SG_IO_HDR)
 635                 return -EINVAL;
 636         if (!access_ok(VERIFY_READ, buf, count))
 637                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 638
 639         sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
 640         if (!(srp = sg_add_request(sfp))) {
 641                 SCSI_LOG_TIMEOUT(1, printk("sg_new_write: queue full\n"));
 642                 return -EDOM;
 643         }
 644         hp = &srp->header;
 645         if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
 646                 sg_remove_request(sfp, srp);
 647                 return -EFAULT;
 648         }
 649         if (hp->interface_id != 'S') {
 650                 sg_remove_request(sfp, srp);
 651                 return -ENOSYS;
 652         }
 653         if (hp->flags & SG_FLAG_MMAP_IO) {
 654                 if (hp->dxfer_len > sfp->reserve.bufflen) {
 655                         sg_remove_request(sfp, srp);
 656                         return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
 657                 }
 658                 if (hp->flags & SG_FLAG_DIRECT_IO) {
 659                         sg_remove_request(sfp, srp);
 660                         return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
 661                 }
 662                 if (sg_res_in_use(sfp)) {
 663                         sg_remove_request(sfp, srp);
 664                         return -EBUSY;  /* reserve buffer already being used */
 665                 }
 666         }
 667         ul_timeout = msecs_to_jiffies(srp->header.timeout);
 668         timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
 669         if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
 670                 sg_remove_request(sfp, srp);
 671                 return -EMSGSIZE;
 672         }
 673         if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
 674                 sg_remove_request(sfp, srp);
 675                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 676         }
 677         if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
 678                 sg_remove_request(sfp, srp);
 679                 return -EFAULT;
 680         }
 681         if (read_only &&
 682             (!sg_allow_access(cmnd[0], sfp->parentdp->device->type))) {
 683                 sg_remove_request(sfp, srp);
 684                 return -EPERM;
 685         }
 686         k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
 687         if (k < 0)
 688                 return k;
 689         if (o_srp)
 690                 *o_srp = srp;
 691         return count;
 692 }
 693
 694 static int
 695 sg_common_write(Sg_fd * sfp, Sg_request * srp,
 696                 unsigned char *cmnd, int timeout, int blocking)
 697 {
 698         int k, data_dir;
 699         Sg_device *sdp = sfp->parentdp;
 700         sg_io_hdr_t *hp = &srp->header;
 701
 702         srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
 703         hp->status = 0;
 704         hp->masked_status = 0;
 705         hp->msg_status = 0;
 706         hp->info = 0;
 707         hp->host_status = 0;
 708         hp->driver_status = 0;
 709         hp->resid = 0;
 710         SCSI_LOG_TIMEOUT(4, printk("sg_common_write:  scsi opcode=0x%02x, cmd_size=%d\n",
 711                           (int) cmnd[0], (int) hp->cmd_len));
 712
 713         if ((k = sg_start_req(srp))) {
 714                 SCSI_LOG_TIMEOUT(1, printk("sg_common_write: start_req err=%d\n", k));
 715                 sg_finish_rem_req(srp);
 716                 return k;       /* probably out of space --> ENOMEM */
 717         }
 718         if ((k = sg_write_xfer(srp))) {
 719                 SCSI_LOG_TIMEOUT(1, printk("sg_common_write: write_xfer, bad address\n"));
 720                 sg_finish_rem_req(srp);
 721                 return k;
 722         }
 723         if (sdp->detached) {
 724                 sg_finish_rem_req(srp);
 725                 return -ENODEV;
 726         }
 727
 728         switch (hp->dxfer_direction) {
 729         case SG_DXFER_TO_FROM_DEV:
 730         case SG_DXFER_FROM_DEV:
 731                 data_dir = DMA_FROM_DEVICE;
 732                 break;
 733         case SG_DXFER_TO_DEV:
 734                 data_dir = DMA_TO_DEVICE;
 735                 break;
 736         case SG_DXFER_UNKNOWN:
 737                 data_dir = DMA_BIDIRECTIONAL;
 738                 break;
 739         default:
 740                 data_dir = DMA_NONE;
 741                 break;
 742         }
 743         hp->duration = jiffies_to_msecs(jiffies);
 744 /* Now send everything of to mid-level. The next time we hear about this
 745    packet is when sg_cmd_done() is called (i.e. a callback). */
 746         if (scsi_execute_async(sdp->device, cmnd, hp->cmd_len, data_dir, srp->data.buffer,
 747                                 hp->dxfer_len, srp->data.k_use_sg, timeout,
 748                                 SG_DEFAULT_RETRIES, srp, sg_cmd_done,
 749                                 GFP_ATOMIC)) {
 750                 SCSI_LOG_TIMEOUT(1, printk("sg_common_write: scsi_execute_async failed\n"));
 751                 /*
 752                  * most likely out of mem, but could also be a bad map
 753                  */
 754                 sg_finish_rem_req(srp);
 755                 return -ENOMEM;
 756         } else
 757                 return 0;
 758 }
 759
 760 static int
 761 sg_srp_done(Sg_request *srp, Sg_fd *sfp)
 762 {
 763         unsigned long iflags;
 764         int done;
 765
 766         read_lock_irqsave(&sfp->rq_list_lock, iflags);
 767         done = srp->done;
 768         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 769         return done;
 770 }
 771
 772 static int
 773 sg_ioctl(struct inode *inode, struct file *filp,
 774          unsigned int cmd_in, unsigned long arg)
 775 {
 776         void __user *p = (void __user *)arg;
 777         int __user *ip = p;
 778         int result, val, read_only;
 779         Sg_device *sdp;
 780         Sg_fd *sfp;
 781         Sg_request *srp;
 782         unsigned long iflags;
 783
 784         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 785                 return -ENXIO;
 786         SCSI_LOG_TIMEOUT(3, printk("sg_ioctl: %s, cmd=0x%x\n",
 787                                    sdp->disk->disk_name, (int) cmd_in));
 788         read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
 789
 790         switch (cmd_in) {
 791         case SG_IO:
 792                 {
 793                         int blocking = 1;       /* ignore O_NONBLOCK flag */
 794
 795                         if (sdp->detached)
 796                                 return -ENODEV;
 797                         if (!scsi_block_when_processing_errors(sdp->device))
 798                                 return -ENXIO;
 799                         if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
 800                                 return -EFAULT;
 801                         result =
 802                             sg_new_write(sfp, p, SZ_SG_IO_HDR,
 803                                          blocking, read_only, &srp);
 804                         if (result < 0)
 805                                 return result;
 806                         srp->sg_io_owned = 1;
 807                         while (1) {
 808                                 result = 0;     /* following macro to beat race condition */
 809                                 __wait_event_interruptible(sfp->read_wait,
 810                                         (sdp->detached || sfp->closed || sg_srp_done(srp, sfp)),
 811                                                            result);
 812                                 if (sdp->detached)
 813                                         return -ENODEV;
 814                                 if (sfp->closed)
 815                                         return 0;       /* request packet dropped already */
 816                                 if (0 == result)
 817                                         break;
 818                                 srp->orphan = 1;
 819                                 return result;  /* -ERESTARTSYS because signal hit process */
 820                         }
 821                         write_lock_irqsave(&sfp->rq_list_lock, iflags);
 822                         srp->done = 2;
 823                         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 824                         result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
 825                         return (result < 0) ? result : 0;
 826                 }
 827         case SG_SET_TIMEOUT:
 828                 result = get_user(val, ip);
 829                 if (result)
 830                         return result;
 831                 if (val < 0)
 832                         return -EIO;
 833                 if (val >= MULDIV (INT_MAX, USER_HZ, HZ))
 834                     val = MULDIV (INT_MAX, USER_HZ, HZ);
 835                 sfp->timeout_user = val;
 836                 sfp->timeout = MULDIV (val, HZ, USER_HZ);
 837
 838                 return 0;
 839         case SG_GET_TIMEOUT:    /* N.B. User receives timeout as return value */
 840                                 /* strange ..., for backward compatibility */
 841                 return sfp->timeout_user;
 842         case SG_SET_FORCE_LOW_DMA:
 843                 result = get_user(val, ip);
 844                 if (result)
 845                         return result;
 846                 if (val) {
 847                         sfp->low_dma = 1;
 848                         if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
 849                                 val = (int) sfp->reserve.bufflen;
 850                                 sg_remove_scat(&sfp->reserve);
 851                                 sg_build_reserve(sfp, val);
 852                         }
 853                 } else {
 854                         if (sdp->detached)
 855                                 return -ENODEV;
 856                         sfp->low_dma = sdp->device->host->unchecked_isa_dma;
 857                 }
 858                 return 0;
 859         case SG_GET_LOW_DMA:
 860                 return put_user((int) sfp->low_dma, ip);
 861         case SG_GET_SCSI_ID:
 862                 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
 863                         return -EFAULT;
 864                 else {
 865                         sg_scsi_id_t __user *sg_idp = p;
 866
 867                         if (sdp->detached)
 868                                 return -ENODEV;
 869                         __put_user((int) sdp->device->host->host_no,
 870                                    &sg_idp->host_no);
 871                         __put_user((int) sdp->device->channel,
 872                                    &sg_idp->channel);
 873                         __put_user((int) sdp->device->id, &sg_idp->scsi_id);
 874                         __put_user((int) sdp->device->lun, &sg_idp->lun);
 875                         __put_user((int) sdp->device->type, &sg_idp->scsi_type);
 876                         __put_user((short) sdp->device->host->cmd_per_lun,
 877                                    &sg_idp->h_cmd_per_lun);
 878                         __put_user((short) sdp->device->queue_depth,
 879                                    &sg_idp->d_queue_depth);
 880                         __put_user(0, &sg_idp->unused[0]);
 881                         __put_user(0, &sg_idp->unused[1]);
 882                         return 0;
 883                 }
 884         case SG_SET_FORCE_PACK_ID:
 885                 result = get_user(val, ip);
 886                 if (result)
 887                         return result;
 888                 sfp->force_packid = val ? 1 : 0;
 889                 return 0;
 890         case SG_GET_PACK_ID:
 891                 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
 892                         return -EFAULT;
 893                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 894                 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
 895                         if ((1 == srp->done) && (!srp->sg_io_owned)) {
 896                                 read_unlock_irqrestore(&sfp->rq_list_lock,
 897                                                        iflags);
 898                                 __put_user(srp->header.pack_id, ip);
 899                                 return 0;
 900                         }
 901                 }
 902                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 903                 __put_user(-1, ip);
 904                 return 0;
 905         case SG_GET_NUM_WAITING:
 906                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 907                 for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) {
 908                         if ((1 == srp->done) && (!srp->sg_io_owned))
 909                                 ++val;
 910                 }
 911                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 912                 return put_user(val, ip);
 913         case SG_GET_SG_TABLESIZE:
 914                 return put_user(sdp->sg_tablesize, ip);
 915         case SG_SET_RESERVED_SIZE:
 916                 result = get_user(val, ip);
 917                 if (result)
 918                         return result;
 919                 if (val < 0)
 920                         return -EINVAL;
 921                 val = min_t(int, val,
 922                                 sdp->device->request_queue->max_sectors * 512);
 923                 if (val != sfp->reserve.bufflen) {
 924                         if (sg_res_in_use(sfp) || sfp->mmap_called)
 925                                 return -EBUSY;
 926                         sg_remove_scat(&sfp->reserve);
 927                         sg_build_reserve(sfp, val);
 928                 }
 929                 return 0;
 930         case SG_GET_RESERVED_SIZE:
 931                 val = min_t(int, sfp->reserve.bufflen,
 932                                 sdp->device->request_queue->max_sectors * 512);
 933                 return put_user(val, ip);
 934         case SG_SET_COMMAND_Q:
 935                 result = get_user(val, ip);
 936                 if (result)
 937                         return result;
 938                 sfp->cmd_q = val ? 1 : 0;
 939                 return 0;
 940         case SG_GET_COMMAND_Q:
 941                 return put_user((int) sfp->cmd_q, ip);
 942         case SG_SET_KEEP_ORPHAN:
 943                 result = get_user(val, ip);
 944                 if (result)
 945                         return result;
 946                 sfp->keep_orphan = val;
 947                 return 0;
 948         case SG_GET_KEEP_ORPHAN:
 949                 return put_user((int) sfp->keep_orphan, ip);
 950         case SG_NEXT_CMD_LEN:
 951                 result = get_user(val, ip);
 952                 if (result)
 953                         return result;
 954                 sfp->next_cmd_len = (val > 0) ? val : 0;
 955                 return 0;
 956         case SG_GET_VERSION_NUM:
 957                 return put_user(sg_version_num, ip);
 958         case SG_GET_ACCESS_COUNT:
 959                 /* faked - we don't have a real access count anymore */
 960                 val = (sdp->device ? 1 : 0);
 961                 return put_user(val, ip);
 962         case SG_GET_REQUEST_TABLE:
 963                 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
 964                         return -EFAULT;
 965                 else {
 966                         sg_req_info_t *rinfo;
 967                         unsigned int ms;
 968
 969                         rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
 970                                                                 GFP_KERNEL);
 971                         if (!rinfo)
 972                                 return -ENOMEM;
 973                         read_lock_irqsave(&sfp->rq_list_lock, iflags);
 974                         for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE;
 975                              ++val, srp = srp ? srp->nextrp : srp) {
 976                                 memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
 977                                 if (srp) {
 978                                         rinfo[val].req_state = srp->done + 1;
 979                                         rinfo[val].problem =
 980                                             srp->header.masked_status &
 981                                             srp->header.host_status &
 982                                             srp->header.driver_status;
 983                                         if (srp->done)
 984                                                 rinfo[val].duration =
 985                                                         srp->header.duration;
 986                                         else {
 987                                                 ms = jiffies_to_msecs(jiffies);
 988                                                 rinfo[val].duration =
 989                                                     (ms > srp->header.duration) ?
 990                                                     (ms - srp->header.duration) : 0;
 991                                         }
 992                                         rinfo[val].orphan = srp->orphan;
 993                                         rinfo[val].sg_io_owned =
 994                                                         srp->sg_io_owned;
 995                                         rinfo[val].pack_id =
 996                                                         srp->header.pack_id;
 997                                         rinfo[val].usr_ptr =
 998                                                         srp->header.usr_ptr;
 999                                 }
1000                         }
1001                         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1002                         result = __copy_to_user(p, rinfo,
1003                                                 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1004                         result = result ? -EFAULT : 0;
1005                         kfree(rinfo);
1006                         return result;
1007                 }
1008         case SG_EMULATED_HOST:
1009                 if (sdp->detached)
1010                         return -ENODEV;
1011                 return put_user(sdp->device->host->hostt->emulated, ip);
1012         case SG_SCSI_RESET:
1013                 if (sdp->detached)
1014                         return -ENODEV;
1015                 if (filp->f_flags & O_NONBLOCK) {
1016                         if (scsi_host_in_recovery(sdp->device->host))
1017                                 return -EBUSY;
1018                 } else if (!scsi_block_when_processing_errors(sdp->device))
1019                         return -EBUSY;
1020                 result = get_user(val, ip);
1021                 if (result)
1022                         return result;
1023                 if (SG_SCSI_RESET_NOTHING == val)
1024                         return 0;
1025                 switch (val) {
1026                 case SG_SCSI_RESET_DEVICE:
1027                         val = SCSI_TRY_RESET_DEVICE;
1028                         break;
1029                 case SG_SCSI_RESET_BUS:
1030                         val = SCSI_TRY_RESET_BUS;
1031                         break;
1032                 case SG_SCSI_RESET_HOST:
1033                         val = SCSI_TRY_RESET_HOST;
1034                         break;
1035                 default:
1036                         return -EINVAL;
1037                 }
1038                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1039                         return -EACCES;
1040                 return (scsi_reset_provider(sdp->device, val) ==
1041                         SUCCESS) ? 0 : -EIO;
1042         case SCSI_IOCTL_SEND_COMMAND:
1043                 if (sdp->detached)
1044                         return -ENODEV;
1045                 if (read_only) {
1046                         unsigned char opcode = WRITE_6;
1047                         Scsi_Ioctl_Command __user *siocp = p;
1048
1049                         if (copy_from_user(&opcode, siocp->data, 1))
1050                                 return -EFAULT;
1051                         if (!sg_allow_access(opcode, sdp->device->type))
1052                                 return -EPERM;
1053                 }
1054                 return sg_scsi_ioctl(filp, sdp->device->request_queue, NULL, p);
1055         case SG_SET_DEBUG:
1056                 result = get_user(val, ip);
1057                 if (result)
1058                         return result;
1059                 sdp->sgdebug = (char) val;
1060                 return 0;
1061         case SCSI_IOCTL_GET_IDLUN:
1062         case SCSI_IOCTL_GET_BUS_NUMBER:
1063         case SCSI_IOCTL_PROBE_HOST:
1064         case SG_GET_TRANSFORM:
1065                 if (sdp->detached)
1066                         return -ENODEV;
1067                 return scsi_ioctl(sdp->device, cmd_in, p);
1068         case BLKSECTGET:
1069                 return put_user(sdp->device->request_queue->max_sectors * 512,
1070                                 ip);
1071         case BLKTRACESETUP:
1072                 return blk_trace_setup(sdp->device->request_queue,
1073                                        sdp->disk->disk_name,
1074                                        sdp->device->sdev_gendev.devt,
1075                                        (char *)arg);
1076         case BLKTRACESTART:
1077                 return blk_trace_startstop(sdp->device->request_queue, 1);
1078         case BLKTRACESTOP:
1079                 return blk_trace_startstop(sdp->device->request_queue, 0);
1080         case BLKTRACETEARDOWN:
1081                 return blk_trace_remove(sdp->device->request_queue);
1082         default:
1083                 if (read_only)
1084                         return -EPERM;  /* don't know so take safe approach */
1085                 return scsi_ioctl(sdp->device, cmd_in, p);
1086         }
1087 }
1088
1089 #ifdef CONFIG_COMPAT
1090 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1091 {
1092         Sg_device *sdp;
1093         Sg_fd *sfp;
1094         struct scsi_device *sdev;
1095
1096         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1097                 return -ENXIO;
1098
1099         sdev = sdp->device;
1100         if (sdev->host->hostt->compat_ioctl) {
1101                 int ret;
1102
1103                 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1104
1105                 return ret;
1106         }
1107
1108         return -ENOIOCTLCMD;
1109 }
1110 #endif
1111
1112 static unsigned int
1113 sg_poll(struct file *filp, poll_table * wait)
1114 {
1115         unsigned int res = 0;
1116         Sg_device *sdp;
1117         Sg_fd *sfp;
1118         Sg_request *srp;
1119         int count = 0;
1120         unsigned long iflags;
1121
1122         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))
1123             || sfp->closed)
1124                 return POLLERR;
1125         poll_wait(filp, &sfp->read_wait, wait);
1126         read_lock_irqsave(&sfp->rq_list_lock, iflags);
1127         for (srp = sfp->headrp; srp; srp = srp->nextrp) {
1128                 /* if any read waiting, flag it */
1129                 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1130                         res = POLLIN | POLLRDNORM;
1131                 ++count;
1132         }
1133         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1134
1135         if (sdp->detached)
1136                 res |= POLLHUP;
1137         else if (!sfp->cmd_q) {
1138                 if (0 == count)
1139                         res |= POLLOUT | POLLWRNORM;
1140         } else if (count < SG_MAX_QUEUE)
1141                 res |= POLLOUT | POLLWRNORM;
1142         SCSI_LOG_TIMEOUT(3, printk("sg_poll: %s, res=0x%x\n",
1143                                    sdp->disk->disk_name, (int) res));
1144         return res;
1145 }
1146
1147 static int
1148 sg_fasync(int fd, struct file *filp, int mode)
1149 {
1150         int retval;
1151         Sg_device *sdp;
1152         Sg_fd *sfp;
1153
1154         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1155                 return -ENXIO;
1156         SCSI_LOG_TIMEOUT(3, printk("sg_fasync: %s, mode=%d\n",
1157                                    sdp->disk->disk_name, mode));
1158
1159         retval = fasync_helper(fd, filp, mode, &sfp->async_qp);
1160         return (retval < 0) ? retval : 0;
1161 }
1162
1163 static int
1164 sg_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1165 {
1166         Sg_fd *sfp;
1167         unsigned long offset, len, sa;
1168         Sg_scatter_hold *rsv_schp;
1169         struct scatterlist *sg;
1170         int k;
1171
1172         if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1173                 return VM_FAULT_SIGBUS;
1174         rsv_schp = &sfp->reserve;
1175         offset = vmf->pgoff << PAGE_SHIFT;
1176         if (offset >= rsv_schp->bufflen)
1177                 return VM_FAULT_SIGBUS;
1178         SCSI_LOG_TIMEOUT(3, printk("sg_vma_fault: offset=%lu, scatg=%d\n",
1179                                    offset, rsv_schp->k_use_sg));
1180         sg = rsv_schp->buffer;
1181         sa = vma->vm_start;
1182         for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
1183              ++k, sg = sg_next(sg)) {
1184                 len = vma->vm_end - sa;
1185                 len = (len < sg->length) ? len : sg->length;
1186                 if (offset < len) {
1187                         struct page *page;
1188                         page = virt_to_page(page_address(sg_page(sg)) + offset);
1189                         get_page(page); /* increment page count */
1190                         vmf->page = page;
1191                         return 0; /* success */
1192                 }
1193                 sa += len;
1194                 offset -= len;
1195         }
1196
1197         return VM_FAULT_SIGBUS;
1198 }
1199
1200 static struct vm_operations_struct sg_mmap_vm_ops = {
1201         .fault = sg_vma_fault,
1202 };
1203
1204 static int
1205 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1206 {
1207         Sg_fd *sfp;
1208         unsigned long req_sz, len, sa;
1209         Sg_scatter_hold *rsv_schp;
1210         int k;
1211         struct scatterlist *sg;
1212
1213         if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1214                 return -ENXIO;
1215         req_sz = vma->vm_end - vma->vm_start;
1216         SCSI_LOG_TIMEOUT(3, printk("sg_mmap starting, vm_start=%p, len=%d\n",
1217                                    (void *) vma->vm_start, (int) req_sz));
1218         if (vma->vm_pgoff)
1219                 return -EINVAL; /* want no offset */
1220         rsv_schp = &sfp->reserve;
1221         if (req_sz > rsv_schp->bufflen)
1222                 return -ENOMEM; /* cannot map more than reserved buffer */
1223
1224         sa = vma->vm_start;
1225         sg = rsv_schp->buffer;
1226         for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
1227              ++k, sg = sg_next(sg)) {
1228                 len = vma->vm_end - sa;
1229                 len = (len < sg->length) ? len : sg->length;
1230                 sa += len;
1231         }
1232
1233         sfp->mmap_called = 1;
1234         vma->vm_flags |= VM_RESERVED;
1235         vma->vm_private_data = sfp;
1236         vma->vm_ops = &sg_mmap_vm_ops;
1237         return 0;
1238 }
1239
1240 /* This function is a "bottom half" handler that is called by the
1241  * mid level when a command is completed (or has failed). */
1242 static void
1243 sg_cmd_done(void *data, char *sense, int result, int resid)
1244 {
1245         Sg_request *srp = data;
1246         Sg_device *sdp = NULL;
1247         Sg_fd *sfp;
1248         unsigned long iflags;
1249         unsigned int ms;
1250
1251         if (NULL == srp) {
1252                 printk(KERN_ERR "sg_cmd_done: NULL request\n");
1253                 return;
1254         }
1255         sfp = srp->parentfp;
1256         if (sfp)
1257                 sdp = sfp->parentdp;
1258         if ((NULL == sdp) || sdp->detached) {
1259                 printk(KERN_INFO "sg_cmd_done: device detached\n");
1260                 return;
1261         }
1262
1263
1264         SCSI_LOG_TIMEOUT(4, printk("sg_cmd_done: %s, pack_id=%d, res=0x%x\n",
1265                 sdp->disk->disk_name, srp->header.pack_id, result));
1266         srp->header.resid = resid;
1267         ms = jiffies_to_msecs(jiffies);
1268         srp->header.duration = (ms > srp->header.duration) ?
1269                                 (ms - srp->header.duration) : 0;
1270         if (0 != result) {
1271                 struct scsi_sense_hdr sshdr;
1272
1273                 memcpy(srp->sense_b, sense, sizeof (srp->sense_b));
1274                 srp->header.status = 0xff & result;
1275                 srp->header.masked_status = status_byte(result);
1276                 srp->header.msg_status = msg_byte(result);
1277                 srp->header.host_status = host_byte(result);
1278                 srp->header.driver_status = driver_byte(result);
1279                 if ((sdp->sgdebug > 0) &&
1280                     ((CHECK_CONDITION == srp->header.masked_status) ||
1281                      (COMMAND_TERMINATED == srp->header.masked_status)))
1282                         __scsi_print_sense("sg_cmd_done", sense,
1283                                            SCSI_SENSE_BUFFERSIZE);
1284
1285                 /* Following if statement is a patch supplied by Eric Youngdale */
1286                 if (driver_byte(result) != 0
1287                     && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1288                     && !scsi_sense_is_deferred(&sshdr)
1289                     && sshdr.sense_key == UNIT_ATTENTION
1290                     && sdp->device->removable) {
1291                         /* Detected possible disc change. Set the bit - this */
1292                         /* may be used if there are filesystems using this device */
1293                         sdp->device->changed = 1;
1294                 }
1295         }
1296         /* Rely on write phase to clean out srp status values, so no "else" */
1297
1298         if (sfp->closed) {      /* whoops this fd already released, cleanup */
1299                 SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, freeing ...\n"));
1300                 sg_finish_rem_req(srp);
1301                 srp = NULL;
1302                 if (NULL == sfp->headrp) {
1303                         SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, final cleanup\n"));
1304                         if (0 == sg_remove_sfp(sdp, sfp)) {     /* device still present */
1305                                 scsi_device_put(sdp->device);
1306                         }
1307                         sfp = NULL;
1308                 }
1309         } else if (srp && srp->orphan) {
1310                 if (sfp->keep_orphan)
1311                         srp->sg_io_owned = 0;
1312                 else {
1313                         sg_finish_rem_req(srp);
1314                         srp = NULL;
1315                 }
1316         }
1317         if (sfp && srp) {
1318                 /* Now wake up any sg_read() that is waiting for this packet. */
1319                 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1320                 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1321                 srp->done = 1;
1322                 wake_up_interruptible(&sfp->read_wait);
1323                 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1324         }
1325 }
1326
1327 static struct file_operations sg_fops = {
1328         .owner = THIS_MODULE,
1329         .read = sg_read,
1330         .write = sg_write,
1331         .poll = sg_poll,
1332         .ioctl = sg_ioctl,
1333 #ifdef CONFIG_COMPAT
1334         .compat_ioctl = sg_compat_ioctl,
1335 #endif
1336         .open = sg_open,
1337         .mmap = sg_mmap,
1338         .release = sg_release,
1339         .fasync = sg_fasync,
1340 };
1341
1342 static struct class *sg_sysfs_class;
1343
1344 static int sg_sysfs_valid = 0;
1345
1346 static Sg_device *sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1347 {
1348         struct request_queue *q = scsidp->request_queue;
1349         Sg_device *sdp;
1350         unsigned long iflags;
1351         int error;
1352         u32 k;
1353
1354         sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1355         if (!sdp) {
1356                 printk(KERN_WARNING "kmalloc Sg_device failure\n");
1357                 return ERR_PTR(-ENOMEM);
1358         }
1359         error = -ENOMEM;
1360         if (!idr_pre_get(&sg_index_idr, GFP_KERNEL)) {
1361                 printk(KERN_WARNING "idr expansion Sg_device failure\n");
1362                 goto out;
1363         }
1364
1365         write_lock_irqsave(&sg_index_lock, iflags);
1366         error = idr_get_new(&sg_index_idr, sdp, &k);
1367         write_unlock_irqrestore(&sg_index_lock, iflags);
1368
1369         if (error) {
1370                 printk(KERN_WARNING "idr allocation Sg_device failure: %d\n",
1371                        error);
1372                 goto out;
1373         }
1374
1375         if (unlikely(k >= SG_MAX_DEVS))
1376                 goto overflow;
1377
1378         SCSI_LOG_TIMEOUT(3, printk("sg_alloc: dev=%d \n", k));
1379         sprintf(disk->disk_name, "sg%d", k);
1380         disk->first_minor = k;
1381         sdp->disk = disk;
1382         sdp->device = scsidp;
1383         init_waitqueue_head(&sdp->o_excl_wait);
1384         sdp->sg_tablesize = min(q->max_hw_segments, q->max_phys_segments);
1385         sdp->index = k;
1386
1387         error = 0;
1388  out:
1389         if (error) {
1390                 kfree(sdp);
1391                 return ERR_PTR(error);
1392         }
1393         return sdp;
1394
1395  overflow:
1396         sdev_printk(KERN_WARNING, scsidp,
1397                     "Unable to attach sg device type=%d, minor "
1398                     "number exceeds %d\n", scsidp->type, SG_MAX_DEVS - 1);
1399         error = -ENODEV;
1400         goto out;
1401 }
1402
1403 static int
1404 sg_add(struct device *cl_dev, struct class_interface *cl_intf)
1405 {
1406         struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1407         struct gendisk *disk;
1408         Sg_device *sdp = NULL;
1409         struct cdev * cdev = NULL;
1410         int error;
1411         unsigned long iflags;
1412
1413         disk = alloc_disk(1);
1414         if (!disk) {
1415                 printk(KERN_WARNING "alloc_disk failed\n");
1416                 return -ENOMEM;
1417         }
1418         disk->major = SCSI_GENERIC_MAJOR;
1419
1420         error = -ENOMEM;
1421         cdev = cdev_alloc();
1422         if (!cdev) {
1423                 printk(KERN_WARNING "cdev_alloc failed\n");
1424                 goto out;
1425         }
1426         cdev->owner = THIS_MODULE;
1427         cdev->ops = &sg_fops;
1428
1429         sdp = sg_alloc(disk, scsidp);
1430         if (IS_ERR(sdp)) {
1431                 printk(KERN_WARNING "sg_alloc failed\n");
1432                 error = PTR_ERR(sdp);
1433                 goto out;
1434         }
1435
1436         error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1437         if (error)
1438                 goto cdev_add_err;
1439
1440         sdp->cdev = cdev;
1441         if (sg_sysfs_valid) {
1442                 struct device *sg_class_member;
1443
1444                 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1445                                                 MKDEV(SCSI_GENERIC_MAJOR,
1446                                                       sdp->index),
1447                                                 "%s", disk->disk_name);
1448                 if (IS_ERR(sg_class_member)) {
1449                         printk(KERN_ERR "sg_add: "
1450                                "device_create failed\n");
1451                         error = PTR_ERR(sg_class_member);
1452                         goto cdev_add_err;
1453                 }
1454                 dev_set_drvdata(sg_class_member, sdp);
1455                 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1456                                           &sg_class_member->kobj, "generic");
1457                 if (error)
1458                         printk(KERN_ERR "sg_add: unable to make symlink "
1459                                         "'generic' back to sg%d\n", sdp->index);
1460         } else
1461                 printk(KERN_WARNING "sg_add: sg_sys Invalid\n");
1462
1463         sdev_printk(KERN_NOTICE, scsidp,
1464                     "Attached scsi generic sg%d type %d\n", sdp->index,
1465                     scsidp->type);
1466
1467         dev_set_drvdata(cl_dev, sdp);
1468
1469         return 0;
1470
1471 cdev_add_err:
1472         write_lock_irqsave(&sg_index_lock, iflags);
1473         idr_remove(&sg_index_idr, sdp->index);
1474         write_unlock_irqrestore(&sg_index_lock, iflags);
1475         kfree(sdp);
1476
1477 out:
1478         put_disk(disk);
1479         if (cdev)
1480                 cdev_del(cdev);
1481         return error;
1482 }
1483
1484 static void
1485 sg_remove(struct device *cl_dev, struct class_interface *cl_intf)
1486 {
1487         struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1488         Sg_device *sdp = dev_get_drvdata(cl_dev);
1489         unsigned long iflags;
1490         Sg_fd *sfp;
1491         Sg_fd *tsfp;
1492         Sg_request *srp;
1493         Sg_request *tsrp;
1494         int delay;
1495
1496         if (!sdp)
1497                 return;
1498
1499         delay = 0;
1500         write_lock_irqsave(&sg_index_lock, iflags);
1501         if (sdp->headfp) {
1502                 sdp->detached = 1;
1503                 for (sfp = sdp->headfp; sfp; sfp = tsfp) {
1504                         tsfp = sfp->nextfp;
1505                         for (srp = sfp->headrp; srp; srp = tsrp) {
1506                                 tsrp = srp->nextrp;
1507                                 if (sfp->closed || (0 == sg_srp_done(srp, sfp)))
1508                                         sg_finish_rem_req(srp);
1509                         }
1510                         if (sfp->closed) {
1511                                 scsi_device_put(sdp->device);
1512                                 __sg_remove_sfp(sdp, sfp);
1513                         } else {
1514                                 delay = 1;
1515                                 wake_up_interruptible(&sfp->read_wait);
1516                                 kill_fasync(&sfp->async_qp, SIGPOLL,
1517                                             POLL_HUP);
1518                         }
1519                 }
1520                 SCSI_LOG_TIMEOUT(3, printk("sg_remove: dev=%d, dirty\n", sdp->index));
1521                 if (NULL == sdp->headfp) {
1522                         idr_remove(&sg_index_idr, sdp->index);
1523                 }
1524         } else {        /* nothing active, simple case */
1525                 SCSI_LOG_TIMEOUT(3, printk("sg_remove: dev=%d\n", sdp->index));
1526                 idr_remove(&sg_index_idr, sdp->index);
1527         }
1528         write_unlock_irqrestore(&sg_index_lock, iflags);
1529
1530         sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1531         device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1532         cdev_del(sdp->cdev);
1533         sdp->cdev = NULL;
1534         put_disk(sdp->disk);
1535         sdp->disk = NULL;
1536         if (NULL == sdp->headfp)
1537                 kfree(sdp);
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         idr_destroy(&sg_index_idr);
1608 }
1609
1610 static int
1611 sg_start_req(Sg_request * srp)
1612 {
1613         int res;
1614         Sg_fd *sfp = srp->parentfp;
1615         sg_io_hdr_t *hp = &srp->header;
1616         int dxfer_len = (int) hp->dxfer_len;
1617         int dxfer_dir = hp->dxfer_direction;
1618         Sg_scatter_hold *req_schp = &srp->data;
1619         Sg_scatter_hold *rsv_schp = &sfp->reserve;
1620
1621         SCSI_LOG_TIMEOUT(4, printk("sg_start_req: dxfer_len=%d\n", dxfer_len));
1622         if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1623                 return 0;
1624         if (sg_allow_dio && (hp->flags & SG_FLAG_DIRECT_IO) &&
1625             (dxfer_dir != SG_DXFER_UNKNOWN) && (0 == hp->iovec_count) &&
1626             (!sfp->parentdp->device->host->unchecked_isa_dma)) {
1627                 res = sg_build_direct(srp, sfp, dxfer_len);
1628                 if (res <= 0)   /* -ve -> error, 0 -> done, 1 -> try indirect */
1629                         return res;
1630         }
1631         if ((!sg_res_in_use(sfp)) && (dxfer_len <= rsv_schp->bufflen))
1632                 sg_link_reserve(sfp, srp, dxfer_len);
1633         else {
1634                 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1635                 if (res) {
1636                         sg_remove_scat(req_schp);
1637                         return res;
1638                 }
1639         }
1640         return 0;
1641 }
1642
1643 static void
1644 sg_finish_rem_req(Sg_request * srp)
1645 {
1646         Sg_fd *sfp = srp->parentfp;
1647         Sg_scatter_hold *req_schp = &srp->data;
1648
1649         SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n", (int) srp->res_used));
1650         if (srp->res_used)
1651                 sg_unlink_reserve(sfp, srp);
1652         else
1653                 sg_remove_scat(req_schp);
1654         sg_remove_request(sfp, srp);
1655 }
1656
1657 static int
1658 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1659 {
1660         int sg_bufflen = tablesize * sizeof(struct scatterlist);
1661         gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1662
1663         /*
1664          * TODO: test without low_dma, we should not need it since
1665          * the block layer will bounce the buffer for us
1666          *
1667          * XXX(hch): we shouldn't need GFP_DMA for the actual S/G list.
1668          */
1669         if (sfp->low_dma)
1670                  gfp_flags |= GFP_DMA;
1671         schp->buffer = kzalloc(sg_bufflen, gfp_flags);
1672         if (!schp->buffer)
1673                 return -ENOMEM;
1674         sg_init_table(schp->buffer, tablesize);
1675         schp->sglist_len = sg_bufflen;
1676         return tablesize;       /* number of scat_gath elements allocated */
1677 }
1678
1679 #ifdef SG_ALLOW_DIO_CODE
1680 /* vvvvvvvv  following code borrowed from st driver's direct IO vvvvvvvvv */
1681         /* TODO: hopefully we can use the generic block layer code */
1682
1683 /* Pin down user pages and put them into a scatter gather list. Returns <= 0 if
1684    - mapping of all pages not successful
1685    (i.e., either completely successful or fails)
1686 */
1687 static int
1688 st_map_user_pages(struct scatterlist *sgl, const unsigned int max_pages,
1689                   unsigned long uaddr, size_t count, int rw)
1690 {
1691         unsigned long end = (uaddr + count + PAGE_SIZE - 1) >> PAGE_SHIFT;
1692         unsigned long start = uaddr >> PAGE_SHIFT;
1693         const int nr_pages = end - start;
1694         int res, i, j;
1695         struct page **pages;
1696
1697         /* User attempted Overflow! */
1698         if ((uaddr + count) < uaddr)
1699                 return -EINVAL;
1700
1701         /* Too big */
1702         if (nr_pages > max_pages)
1703                 return -ENOMEM;
1704
1705         /* Hmm? */
1706         if (count == 0)
1707                 return 0;
1708
1709         if ((pages = kmalloc(max_pages * sizeof(*pages), GFP_ATOMIC)) == NULL)
1710                 return -ENOMEM;
1711
1712         /* Try to fault in all of the necessary pages */
1713         down_read(&current->mm->mmap_sem);
1714         /* rw==READ means read from drive, write into memory area */
1715         res = get_user_pages(
1716                 current,
1717                 current->mm,
1718                 uaddr,
1719                 nr_pages,
1720                 rw == READ,
1721                 0, /* don't force */
1722                 pages,
1723                 NULL);
1724         up_read(&current->mm->mmap_sem);
1725
1726         /* Errors and no page mapped should return here */
1727         if (res < nr_pages)
1728                 goto out_unmap;
1729
1730         for (i=0; i < nr_pages; i++) {
1731                 /* FIXME: flush superflous for rw==READ,
1732                  * probably wrong function for rw==WRITE
1733                  */
1734                 flush_dcache_page(pages[i]);
1735                 /* ?? Is locking needed? I don't think so */
1736                 /* if (TestSetPageLocked(pages[i]))
1737                    goto out_unlock; */
1738         }
1739
1740         sg_set_page(sgl, pages[0], 0, uaddr & ~PAGE_MASK);
1741         if (nr_pages > 1) {
1742                 sgl[0].length = PAGE_SIZE - sgl[0].offset;
1743                 count -= sgl[0].length;
1744                 for (i=1; i < nr_pages ; i++)
1745                         sg_set_page(&sgl[i], pages[i], count < PAGE_SIZE ? count : PAGE_SIZE, 0);
1746         }
1747         else {
1748                 sgl[0].length = count;
1749         }
1750
1751         kfree(pages);
1752         return nr_pages;
1753
1754  out_unmap:
1755         if (res > 0) {
1756                 for (j=0; j < res; j++)
1757                         page_cache_release(pages[j]);
1758                 res = 0;
1759         }
1760         kfree(pages);
1761         return res;
1762 }
1763
1764
1765 /* And unmap them... */
1766 static int
1767 st_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_pages,
1768                     int dirtied)
1769 {
1770         int i;
1771
1772         for (i=0; i < nr_pages; i++) {
1773                 struct page *page = sg_page(&sgl[i]);
1774
1775                 if (dirtied)
1776                         SetPageDirty(page);
1777                 /* unlock_page(page); */
1778                 /* FIXME: cache flush missing for rw==READ
1779                  * FIXME: call the correct reference counting function
1780                  */
1781                 page_cache_release(page);
1782         }
1783
1784         return 0;
1785 }
1786
1787 /* ^^^^^^^^  above code borrowed from st driver's direct IO ^^^^^^^^^ */
1788 #endif
1789
1790
1791 /* Returns: -ve -> error, 0 -> done, 1 -> try indirect */
1792 static int
1793 sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len)
1794 {
1795 #ifdef SG_ALLOW_DIO_CODE
1796         sg_io_hdr_t *hp = &srp->header;
1797         Sg_scatter_hold *schp = &srp->data;
1798         int sg_tablesize = sfp->parentdp->sg_tablesize;
1799         int mx_sc_elems, res;
1800         struct scsi_device *sdev = sfp->parentdp->device;
1801
1802         if (((unsigned long)hp->dxferp &
1803                         queue_dma_alignment(sdev->request_queue)) != 0)
1804                 return 1;
1805
1806         mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1807         if (mx_sc_elems <= 0) {
1808                 return 1;
1809         }
1810         res = st_map_user_pages(schp->buffer, mx_sc_elems,
1811                                 (unsigned long)hp->dxferp, dxfer_len,
1812                                 (SG_DXFER_TO_DEV == hp->dxfer_direction) ? 1 : 0);
1813         if (res <= 0) {
1814                 sg_remove_scat(schp);
1815                 return 1;
1816         }
1817         schp->k_use_sg = res;
1818         schp->dio_in_use = 1;
1819         hp->info |= SG_INFO_DIRECT_IO;
1820         return 0;
1821 #else
1822         return 1;
1823 #endif
1824 }
1825
1826 static int
1827 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1828 {
1829         struct scatterlist *sg;
1830         int ret_sz = 0, k, rem_sz, num, mx_sc_elems;
1831         int sg_tablesize = sfp->parentdp->sg_tablesize;
1832         int blk_size = buff_size;
1833         struct page *p = NULL;
1834
1835         if (blk_size < 0)
1836                 return -EFAULT;
1837         if (0 == blk_size)
1838                 ++blk_size;     /* don't know why */
1839 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1840         blk_size = (blk_size + SG_SECTOR_MSK) & (~SG_SECTOR_MSK);
1841         SCSI_LOG_TIMEOUT(4, printk("sg_build_indirect: buff_size=%d, blk_size=%d\n",
1842                                    buff_size, blk_size));
1843
1844         /* N.B. ret_sz carried into this block ... */
1845         mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1846         if (mx_sc_elems < 0)
1847                 return mx_sc_elems;     /* most likely -ENOMEM */
1848
1849         num = scatter_elem_sz;
1850         if (unlikely(num != scatter_elem_sz_prev)) {
1851                 if (num < PAGE_SIZE) {
1852                         scatter_elem_sz = PAGE_SIZE;
1853                         scatter_elem_sz_prev = PAGE_SIZE;
1854                 } else
1855                         scatter_elem_sz_prev = num;
1856         }
1857         for (k = 0, sg = schp->buffer, rem_sz = blk_size;
1858              (rem_sz > 0) && (k < mx_sc_elems);
1859              ++k, rem_sz -= ret_sz, sg = sg_next(sg)) {
1860
1861                 num = (rem_sz > scatter_elem_sz_prev) ?
1862                       scatter_elem_sz_prev : rem_sz;
1863                 p = sg_page_malloc(num, sfp->low_dma, &ret_sz);
1864                 if (!p)
1865                         return -ENOMEM;
1866
1867                 if (num == scatter_elem_sz_prev) {
1868                         if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1869                                 scatter_elem_sz = ret_sz;
1870                                 scatter_elem_sz_prev = ret_sz;
1871                         }
1872                 }
1873                 sg_set_page(sg, p, (ret_sz > num) ? num : ret_sz, 0);
1874
1875                 SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k=%d, num=%d, "
1876                                  "ret_sz=%d\n", k, num, ret_sz));
1877         }               /* end of for loop */
1878
1879         schp->k_use_sg = k;
1880         SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, "
1881                          "rem_sz=%d\n", k, rem_sz));
1882
1883         schp->bufflen = blk_size;
1884         if (rem_sz > 0) /* must have failed */
1885                 return -ENOMEM;
1886
1887         return 0;
1888 }
1889
1890 static int
1891 sg_write_xfer(Sg_request * srp)
1892 {
1893         sg_io_hdr_t *hp = &srp->header;
1894         Sg_scatter_hold *schp = &srp->data;
1895         struct scatterlist *sg = schp->buffer;
1896         int num_xfer = 0;
1897         int j, k, onum, usglen, ksglen, res;
1898         int iovec_count = (int) hp->iovec_count;
1899         int dxfer_dir = hp->dxfer_direction;
1900         unsigned char *p;
1901         unsigned char __user *up;
1902         int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
1903
1904         if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_TO_DEV == dxfer_dir) ||
1905             (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
1906                 num_xfer = (int) (new_interface ? hp->dxfer_len : hp->flags);
1907                 if (schp->bufflen < num_xfer)
1908                         num_xfer = schp->bufflen;
1909         }
1910         if ((num_xfer <= 0) || (schp->dio_in_use) ||
1911             (new_interface
1912              && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
1913                 return 0;
1914
1915         SCSI_LOG_TIMEOUT(4, printk("sg_write_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
1916                           num_xfer, iovec_count, schp->k_use_sg));
1917         if (iovec_count) {
1918                 onum = iovec_count;
1919                 if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum))
1920                         return -EFAULT;
1921         } else
1922                 onum = 1;
1923
1924         ksglen = sg->length;
1925         p = page_address(sg_page(sg));
1926         for (j = 0, k = 0; j < onum; ++j) {
1927                 res = sg_u_iovec(hp, iovec_count, j, 1, &usglen, &up);
1928                 if (res)
1929                         return res;
1930
1931                 for (; p; sg = sg_next(sg), ksglen = sg->length,
1932                      p = page_address(sg_page(sg))) {
1933                         if (usglen <= 0)
1934                                 break;
1935                         if (ksglen > usglen) {
1936                                 if (usglen >= num_xfer) {
1937                                         if (__copy_from_user(p, up, num_xfer))
1938                                                 return -EFAULT;
1939                                         return 0;
1940                                 }
1941                                 if (__copy_from_user(p, up, usglen))
1942                                         return -EFAULT;
1943                                 p += usglen;
1944                                 ksglen -= usglen;
1945                                 break;
1946                         } else {
1947                                 if (ksglen >= num_xfer) {
1948                                         if (__copy_from_user(p, up, num_xfer))
1949                                                 return -EFAULT;
1950                                         return 0;
1951                                 }
1952                                 if (__copy_from_user(p, up, ksglen))
1953                                         return -EFAULT;
1954                                 up += ksglen;
1955                                 usglen -= ksglen;
1956                         }
1957                         ++k;
1958                         if (k >= schp->k_use_sg)
1959                                 return 0;
1960                 }
1961         }
1962
1963         return 0;
1964 }
1965
1966 static int
1967 sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
1968            int wr_xf, int *countp, unsigned char __user **up)
1969 {
1970         int num_xfer = (int) hp->dxfer_len;
1971         unsigned char __user *p = hp->dxferp;
1972         int count;
1973
1974         if (0 == sg_num) {
1975                 if (wr_xf && ('\0' == hp->interface_id))
1976                         count = (int) hp->flags;        /* holds "old" input_size */
1977                 else
1978                         count = num_xfer;
1979         } else {
1980                 sg_iovec_t iovec;
1981                 if (__copy_from_user(&iovec, p + ind*SZ_SG_IOVEC, SZ_SG_IOVEC))
1982                         return -EFAULT;
1983                 p = iovec.iov_base;
1984                 count = (int) iovec.iov_len;
1985         }
1986         if (!access_ok(wr_xf ? VERIFY_READ : VERIFY_WRITE, p, count))
1987                 return -EFAULT;
1988         if (up)
1989                 *up = p;
1990         if (countp)
1991                 *countp = count;
1992         return 0;
1993 }
1994
1995 static void
1996 sg_remove_scat(Sg_scatter_hold * schp)
1997 {
1998         SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1999         if (schp->buffer && (schp->sglist_len > 0)) {
2000                 struct scatterlist *sg = schp->buffer;
2001
2002                 if (schp->dio_in_use) {
2003 #ifdef SG_ALLOW_DIO_CODE
2004                         st_unmap_user_pages(sg, schp->k_use_sg, TRUE);
2005 #endif
2006                 } else {
2007                         int k;
2008
2009                         for (k = 0; (k < schp->k_use_sg) && sg_page(sg);
2010                              ++k, sg = sg_next(sg)) {
2011                                 SCSI_LOG_TIMEOUT(5, printk(
2012                                     "sg_remove_scat: k=%d, pg=0x%p, len=%d\n",
2013                                     k, sg_page(sg), sg->length));
2014                                 sg_page_free(sg_page(sg), sg->length);
2015                         }
2016                 }
2017                 kfree(schp->buffer);
2018         }
2019         memset(schp, 0, sizeof (*schp));
2020 }
2021
2022 static int
2023 sg_read_xfer(Sg_request * srp)
2024 {
2025         sg_io_hdr_t *hp = &srp->header;
2026         Sg_scatter_hold *schp = &srp->data;
2027         struct scatterlist *sg = schp->buffer;
2028         int num_xfer = 0;
2029         int j, k, onum, usglen, ksglen, res;
2030         int iovec_count = (int) hp->iovec_count;
2031         int dxfer_dir = hp->dxfer_direction;
2032         unsigned char *p;
2033         unsigned char __user *up;
2034         int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
2035
2036         if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_FROM_DEV == dxfer_dir)
2037             || (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
2038                 num_xfer = hp->dxfer_len;
2039                 if (schp->bufflen < num_xfer)
2040                         num_xfer = schp->bufflen;
2041         }
2042         if ((num_xfer <= 0) || (schp->dio_in_use) ||
2043             (new_interface
2044              && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
2045                 return 0;
2046
2047         SCSI_LOG_TIMEOUT(4, printk("sg_read_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
2048                           num_xfer, iovec_count, schp->k_use_sg));
2049         if (iovec_count) {
2050                 onum = iovec_count;
2051                 if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum))
2052                         return -EFAULT;
2053         } else
2054                 onum = 1;
2055
2056         p = page_address(sg_page(sg));
2057         ksglen = sg->length;
2058         for (j = 0, k = 0; j < onum; ++j) {
2059                 res = sg_u_iovec(hp, iovec_count, j, 0, &usglen, &up);
2060                 if (res)
2061                         return res;
2062
2063                 for (; p; sg = sg_next(sg), ksglen = sg->length,
2064                      p = page_address(sg_page(sg))) {
2065                         if (usglen <= 0)
2066                                 break;
2067                         if (ksglen > usglen) {
2068                                 if (usglen >= num_xfer) {
2069                                         if (__copy_to_user(up, p, num_xfer))
2070                                                 return -EFAULT;
2071                                         return 0;
2072                                 }
2073                                 if (__copy_to_user(up, p, usglen))
2074                                         return -EFAULT;
2075                                 p += usglen;
2076                                 ksglen -= usglen;
2077                                 break;
2078                         } else {
2079                                 if (ksglen >= num_xfer) {
2080                                         if (__copy_to_user(up, p, num_xfer))
2081                                                 return -EFAULT;
2082                                         return 0;
2083                                 }
2084                                 if (__copy_to_user(up, p, ksglen))
2085                                         return -EFAULT;
2086                                 up += ksglen;
2087                                 usglen -= ksglen;
2088                         }
2089                         ++k;
2090                         if (k >= schp->k_use_sg)
2091                                 return 0;
2092                 }
2093         }
2094
2095         return 0;
2096 }
2097
2098 static int
2099 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
2100 {
2101         Sg_scatter_hold *schp = &srp->data;
2102         struct scatterlist *sg = schp->buffer;
2103         int k, num;
2104
2105         SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n",
2106                                    num_read_xfer));
2107         if ((!outp) || (num_read_xfer <= 0))
2108                 return 0;
2109
2110         for (k = 0; (k < schp->k_use_sg) && sg_page(sg); ++k, sg = sg_next(sg)) {
2111                 num = sg->length;
2112                 if (num > num_read_xfer) {
2113                         if (__copy_to_user(outp, page_address(sg_page(sg)),
2114                                            num_read_xfer))
2115                                 return -EFAULT;
2116                         break;
2117                 } else {
2118                         if (__copy_to_user(outp, page_address(sg_page(sg)),
2119                                            num))
2120                                 return -EFAULT;
2121                         num_read_xfer -= num;
2122                         if (num_read_xfer <= 0)
2123                                 break;
2124                         outp += num;
2125                 }
2126         }
2127
2128         return 0;
2129 }
2130
2131 static void
2132 sg_build_reserve(Sg_fd * sfp, int req_size)
2133 {
2134         Sg_scatter_hold *schp = &sfp->reserve;
2135
2136         SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
2137         do {
2138                 if (req_size < PAGE_SIZE)
2139                         req_size = PAGE_SIZE;
2140                 if (0 == sg_build_indirect(schp, sfp, req_size))
2141                         return;
2142                 else
2143                         sg_remove_scat(schp);
2144                 req_size >>= 1; /* divide by 2 */
2145         } while (req_size > (PAGE_SIZE / 2));
2146 }
2147
2148 static void
2149 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2150 {
2151         Sg_scatter_hold *req_schp = &srp->data;
2152         Sg_scatter_hold *rsv_schp = &sfp->reserve;
2153         struct scatterlist *sg = rsv_schp->buffer;
2154         int k, num, rem;
2155
2156         srp->res_used = 1;
2157         SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
2158         rem = size;
2159
2160         for (k = 0; k < rsv_schp->k_use_sg; ++k, sg = sg_next(sg)) {
2161                 num = sg->length;
2162                 if (rem <= num) {
2163                         sfp->save_scat_len = num;
2164                         sg->length = rem;
2165                         req_schp->k_use_sg = k + 1;
2166                         req_schp->sglist_len = rsv_schp->sglist_len;
2167                         req_schp->buffer = rsv_schp->buffer;
2168
2169                         req_schp->bufflen = size;
2170                         req_schp->b_malloc_len = rsv_schp->b_malloc_len;
2171                         break;
2172                 } else
2173                         rem -= num;
2174         }
2175
2176         if (k >= rsv_schp->k_use_sg)
2177                 SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
2178 }
2179
2180 static void
2181 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2182 {
2183         Sg_scatter_hold *req_schp = &srp->data;
2184         Sg_scatter_hold *rsv_schp = &sfp->reserve;
2185
2186         SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->k_use_sg=%d\n",
2187                                    (int) req_schp->k_use_sg));
2188         if ((rsv_schp->k_use_sg > 0) && (req_schp->k_use_sg > 0)) {
2189                 struct scatterlist *sg = rsv_schp->buffer;
2190
2191                 if (sfp->save_scat_len > 0)
2192                         (sg + (req_schp->k_use_sg - 1))->length =
2193                             (unsigned) sfp->save_scat_len;
2194                 else
2195                         SCSI_LOG_TIMEOUT(1, printk ("sg_unlink_reserve: BAD save_scat_len\n"));
2196         }
2197         req_schp->k_use_sg = 0;
2198         req_schp->bufflen = 0;
2199         req_schp->buffer = NULL;
2200         req_schp->sglist_len = 0;
2201         sfp->save_scat_len = 0;
2202         srp->res_used = 0;
2203 }
2204
2205 static Sg_request *
2206 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2207 {
2208         Sg_request *resp;
2209         unsigned long iflags;
2210
2211         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2212         for (resp = sfp->headrp; resp; resp = resp->nextrp) {
2213                 /* look for requests that are ready + not SG_IO owned */
2214                 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2215                     ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2216                         resp->done = 2; /* guard against other readers */
2217                         break;
2218                 }
2219         }
2220         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2221         return resp;
2222 }
2223
2224 #ifdef CONFIG_SCSI_PROC_FS
2225 static Sg_request *
2226 sg_get_nth_request(Sg_fd * sfp, int nth)
2227 {
2228         Sg_request *resp;
2229         unsigned long iflags;
2230         int k;
2231
2232         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2233         for (k = 0, resp = sfp->headrp; resp && (k < nth);
2234              ++k, resp = resp->nextrp) ;
2235         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2236         return resp;
2237 }
2238 #endif
2239
2240 /* always adds to end of list */
2241 static Sg_request *
2242 sg_add_request(Sg_fd * sfp)
2243 {
2244         int k;
2245         unsigned long iflags;
2246         Sg_request *resp;
2247         Sg_request *rp = sfp->req_arr;
2248
2249         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2250         resp = sfp->headrp;
2251         if (!resp) {
2252                 memset(rp, 0, sizeof (Sg_request));
2253                 rp->parentfp = sfp;
2254                 resp = rp;
2255                 sfp->headrp = resp;
2256         } else {
2257                 if (0 == sfp->cmd_q)
2258                         resp = NULL;    /* command queuing disallowed */
2259                 else {
2260                         for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2261                                 if (!rp->parentfp)
2262                                         break;
2263                         }
2264                         if (k < SG_MAX_QUEUE) {
2265                                 memset(rp, 0, sizeof (Sg_request));
2266                                 rp->parentfp = sfp;
2267                                 while (resp->nextrp)
2268                                         resp = resp->nextrp;
2269                                 resp->nextrp = rp;
2270                                 resp = rp;
2271                         } else
2272                                 resp = NULL;
2273                 }
2274         }
2275         if (resp) {
2276                 resp->nextrp = NULL;
2277                 resp->header.duration = jiffies_to_msecs(jiffies);
2278         }
2279         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2280         return resp;
2281 }
2282
2283 /* Return of 1 for found; 0 for not found */
2284 static int
2285 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2286 {
2287         Sg_request *prev_rp;
2288         Sg_request *rp;
2289         unsigned long iflags;
2290         int res = 0;
2291
2292         if ((!sfp) || (!srp) || (!sfp->headrp))
2293                 return res;
2294         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2295         prev_rp = sfp->headrp;
2296         if (srp == prev_rp) {
2297                 sfp->headrp = prev_rp->nextrp;
2298                 prev_rp->parentfp = NULL;
2299                 res = 1;
2300         } else {
2301                 while ((rp = prev_rp->nextrp)) {
2302                         if (srp == rp) {
2303                                 prev_rp->nextrp = rp->nextrp;
2304                                 rp->parentfp = NULL;
2305                                 res = 1;
2306                                 break;
2307                         }
2308                         prev_rp = rp;
2309                 }
2310         }
2311         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2312         return res;
2313 }
2314
2315 #ifdef CONFIG_SCSI_PROC_FS
2316 static Sg_fd *
2317 sg_get_nth_sfp(Sg_device * sdp, int nth)
2318 {
2319         Sg_fd *resp;
2320         unsigned long iflags;
2321         int k;
2322
2323         read_lock_irqsave(&sg_index_lock, iflags);
2324         for (k = 0, resp = sdp->headfp; resp && (k < nth);
2325              ++k, resp = resp->nextfp) ;
2326         read_unlock_irqrestore(&sg_index_lock, iflags);
2327         return resp;
2328 }
2329 #endif
2330
2331 static Sg_fd *
2332 sg_add_sfp(Sg_device * sdp, int dev)
2333 {
2334         Sg_fd *sfp;
2335         unsigned long iflags;
2336         int bufflen;
2337
2338         sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2339         if (!sfp)
2340                 return NULL;
2341
2342         init_waitqueue_head(&sfp->read_wait);
2343         rwlock_init(&sfp->rq_list_lock);
2344
2345         sfp->timeout = SG_DEFAULT_TIMEOUT;
2346         sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2347         sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2348         sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
2349             sdp->device->host->unchecked_isa_dma : 1;
2350         sfp->cmd_q = SG_DEF_COMMAND_Q;
2351         sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2352         sfp->parentdp = sdp;
2353         write_lock_irqsave(&sg_index_lock, iflags);
2354         if (!sdp->headfp)
2355                 sdp->headfp = sfp;
2356         else {                  /* add to tail of existing list */
2357                 Sg_fd *pfp = sdp->headfp;
2358                 while (pfp->nextfp)
2359                         pfp = pfp->nextfp;
2360                 pfp->nextfp = sfp;
2361         }
2362         write_unlock_irqrestore(&sg_index_lock, iflags);
2363         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));
2364         if (unlikely(sg_big_buff != def_reserved_size))
2365                 sg_big_buff = def_reserved_size;
2366
2367         bufflen = min_t(int, sg_big_buff,
2368                         sdp->device->request_queue->max_sectors * 512);
2369         sg_build_reserve(sfp, bufflen);
2370         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp:   bufflen=%d, k_use_sg=%d\n",
2371                            sfp->reserve.bufflen, sfp->reserve.k_use_sg));
2372         return sfp;
2373 }
2374
2375 static void
2376 __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2377 {
2378         Sg_fd *fp;
2379         Sg_fd *prev_fp;
2380
2381         prev_fp = sdp->headfp;
2382         if (sfp == prev_fp)
2383                 sdp->headfp = prev_fp->nextfp;
2384         else {
2385                 while ((fp = prev_fp->nextfp)) {
2386                         if (sfp == fp) {
2387                                 prev_fp->nextfp = fp->nextfp;
2388                                 break;
2389                         }
2390                         prev_fp = fp;
2391                 }
2392         }
2393         if (sfp->reserve.bufflen > 0) {
2394                 SCSI_LOG_TIMEOUT(6,
2395                         printk("__sg_remove_sfp:    bufflen=%d, k_use_sg=%d\n",
2396                         (int) sfp->reserve.bufflen, (int) sfp->reserve.k_use_sg));
2397                 sg_remove_scat(&sfp->reserve);
2398         }
2399         sfp->parentdp = NULL;
2400         SCSI_LOG_TIMEOUT(6, printk("__sg_remove_sfp:    sfp=0x%p\n", sfp));
2401         kfree(sfp);
2402 }
2403
2404 /* Returns 0 in normal case, 1 when detached and sdp object removed */
2405 static int
2406 sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2407 {
2408         Sg_request *srp;
2409         Sg_request *tsrp;
2410         int dirty = 0;
2411         int res = 0;
2412
2413         for (srp = sfp->headrp; srp; srp = tsrp) {
2414                 tsrp = srp->nextrp;
2415                 if (sg_srp_done(srp, sfp))
2416                         sg_finish_rem_req(srp);
2417                 else
2418                         ++dirty;
2419         }
2420         if (0 == dirty) {
2421                 unsigned long iflags;
2422
2423                 write_lock_irqsave(&sg_index_lock, iflags);
2424                 __sg_remove_sfp(sdp, sfp);
2425                 if (sdp->detached && (NULL == sdp->headfp)) {
2426                         idr_remove(&sg_index_idr, sdp->index);
2427                         kfree(sdp);
2428                         res = 1;
2429                 }
2430                 write_unlock_irqrestore(&sg_index_lock, iflags);
2431         } else {
2432                 /* MOD_INC's to inhibit unloading sg and associated adapter driver */
2433                 /* only bump the access_count if we actually succeeded in
2434                  * throwing another counter on the host module */
2435                 scsi_device_get(sdp->device);   /* XXX: retval ignored? */
2436                 sfp->closed = 1;        /* flag dirty state on this fd */
2437                 SCSI_LOG_TIMEOUT(1, printk("sg_remove_sfp: worrisome, %d writes pending\n",
2438                                   dirty));
2439         }
2440         return res;
2441 }
2442
2443 static int
2444 sg_res_in_use(Sg_fd * sfp)
2445 {
2446         const Sg_request *srp;
2447         unsigned long iflags;
2448
2449         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2450         for (srp = sfp->headrp; srp; srp = srp->nextrp)
2451                 if (srp->res_used)
2452                         break;
2453         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2454         return srp ? 1 : 0;
2455 }
2456
2457 /* The size fetched (value output via retSzp) set when non-NULL return */
2458 static struct page *
2459 sg_page_malloc(int rqSz, int lowDma, int *retSzp)
2460 {
2461         struct page *resp = NULL;
2462         gfp_t page_mask;
2463         int order, a_size;
2464         int resSz;
2465
2466         if ((rqSz <= 0) || (NULL == retSzp))
2467                 return resp;
2468
2469         if (lowDma)
2470                 page_mask = GFP_ATOMIC | GFP_DMA | __GFP_COMP | __GFP_NOWARN;
2471         else
2472                 page_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
2473
2474         for (order = 0, a_size = PAGE_SIZE; a_size < rqSz;
2475              order++, a_size <<= 1) ;
2476         resSz = a_size;         /* rounded up if necessary */
2477         resp = alloc_pages(page_mask, order);
2478         while ((!resp) && order) {
2479                 --order;
2480                 a_size >>= 1;   /* divide by 2, until PAGE_SIZE */
2481                 resp =  alloc_pages(page_mask, order);  /* try half */
2482                 resSz = a_size;
2483         }
2484         if (resp) {
2485                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2486                         memset(page_address(resp), 0, resSz);
2487                 *retSzp = resSz;
2488         }
2489         return resp;
2490 }
2491
2492 static void
2493 sg_page_free(struct page *page, int size)
2494 {
2495         int order, a_size;
2496
2497         if (!page)
2498                 return;
2499         for (order = 0, a_size = PAGE_SIZE; a_size < size;
2500              order++, a_size <<= 1) ;
2501         __free_pages(page, order);
2502 }
2503
2504 #ifndef MAINTENANCE_IN_CMD
2505 #define MAINTENANCE_IN_CMD 0xa3
2506 #endif
2507
2508 static unsigned char allow_ops[] = { TEST_UNIT_READY, REQUEST_SENSE,
2509         INQUIRY, READ_CAPACITY, READ_BUFFER, READ_6, READ_10, READ_12,
2510         READ_16, MODE_SENSE, MODE_SENSE_10, LOG_SENSE, REPORT_LUNS,
2511         SERVICE_ACTION_IN, RECEIVE_DIAGNOSTIC, READ_LONG, MAINTENANCE_IN_CMD
2512 };
2513
2514 static int
2515 sg_allow_access(unsigned char opcode, char dev_type)
2516 {
2517         int k;
2518
2519         if (TYPE_SCANNER == dev_type)   /* TYPE_ROM maybe burner */
2520                 return 1;
2521         for (k = 0; k < sizeof (allow_ops); ++k) {
2522                 if (opcode == allow_ops[k])
2523                         return 1;
2524         }
2525         return 0;
2526 }
2527
2528 #ifdef CONFIG_SCSI_PROC_FS
2529 static int
2530 sg_idr_max_id(int id, void *p, void *data)
2531 {
2532         int *k = data;
2533
2534         if (*k < id)
2535                 *k = id;
2536
2537         return 0;
2538 }
2539
2540 static int
2541 sg_last_dev(void)
2542 {
2543         int k = -1;
2544         unsigned long iflags;
2545
2546         read_lock_irqsave(&sg_index_lock, iflags);
2547         idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2548         read_unlock_irqrestore(&sg_index_lock, iflags);
2549         return k + 1;           /* origin 1 */
2550 }
2551 #endif
2552
2553 static Sg_device *
2554 sg_get_dev(int dev)
2555 {
2556         Sg_device *sdp;
2557         unsigned long iflags;
2558
2559         read_lock_irqsave(&sg_index_lock, iflags);
2560         sdp = idr_find(&sg_index_idr, dev);
2561         read_unlock_irqrestore(&sg_index_lock, iflags);
2562
2563         return sdp;
2564 }
2565
2566 #ifdef CONFIG_SCSI_PROC_FS
2567
2568 static struct proc_dir_entry *sg_proc_sgp = NULL;
2569
2570 static char sg_proc_sg_dirname[] = "scsi/sg";
2571
2572 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2573
2574 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2575 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2576                                   size_t count, loff_t *off);
2577 static struct file_operations adio_fops = {
2578         /* .owner, .read and .llseek added in sg_proc_init() */
2579         .open = sg_proc_single_open_adio,
2580         .write = sg_proc_write_adio,
2581         .release = single_release,
2582 };
2583
2584 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2585 static ssize_t sg_proc_write_dressz(struct file *filp,
2586                 const char __user *buffer, size_t count, loff_t *off);
2587 static struct file_operations dressz_fops = {
2588         .open = sg_proc_single_open_dressz,
2589         .write = sg_proc_write_dressz,
2590         .release = single_release,
2591 };
2592
2593 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2594 static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2595 static struct file_operations version_fops = {
2596         .open = sg_proc_single_open_version,
2597         .release = single_release,
2598 };
2599
2600 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2601 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2602 static struct file_operations devhdr_fops = {
2603         .open = sg_proc_single_open_devhdr,
2604         .release = single_release,
2605 };
2606
2607 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2608 static int sg_proc_open_dev(struct inode *inode, struct file *file);
2609 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2610 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2611 static void dev_seq_stop(struct seq_file *s, void *v);
2612 static struct file_operations dev_fops = {
2613         .open = sg_proc_open_dev,
2614         .release = seq_release,
2615 };
2616 static struct seq_operations dev_seq_ops = {
2617         .start = dev_seq_start,
2618         .next  = dev_seq_next,
2619         .stop  = dev_seq_stop,
2620         .show  = sg_proc_seq_show_dev,
2621 };
2622
2623 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2624 static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2625 static struct file_operations devstrs_fops = {
2626         .open = sg_proc_open_devstrs,
2627         .release = seq_release,
2628 };
2629 static struct seq_operations devstrs_seq_ops = {
2630         .start = dev_seq_start,
2631         .next  = dev_seq_next,
2632         .stop  = dev_seq_stop,
2633         .show  = sg_proc_seq_show_devstrs,
2634 };
2635
2636 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2637 static int sg_proc_open_debug(struct inode *inode, struct file *file);
2638 static struct file_operations debug_fops = {
2639         .open = sg_proc_open_debug,
2640         .release = seq_release,
2641 };
2642 static struct seq_operations debug_seq_ops = {
2643         .start = dev_seq_start,
2644         .next  = dev_seq_next,
2645         .stop  = dev_seq_stop,
2646         .show  = sg_proc_seq_show_debug,
2647 };
2648
2649
2650 struct sg_proc_leaf {
2651         const char * name;
2652         struct file_operations * fops;
2653 };
2654
2655 static struct sg_proc_leaf sg_proc_leaf_arr[] = {
2656         {"allow_dio", &adio_fops},
2657         {"debug", &debug_fops},
2658         {"def_reserved_size", &dressz_fops},
2659         {"device_hdr", &devhdr_fops},
2660         {"devices", &dev_fops},
2661         {"device_strs", &devstrs_fops},
2662         {"version", &version_fops}
2663 };
2664
2665 static int
2666 sg_proc_init(void)
2667 {
2668         int k, mask;
2669         int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2670         struct proc_dir_entry *pdep;
2671         struct sg_proc_leaf * leaf;
2672
2673         sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2674         if (!sg_proc_sgp)
2675                 return 1;
2676         for (k = 0; k < num_leaves; ++k) {
2677                 leaf = &sg_proc_leaf_arr[k];
2678                 mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2679                 pdep = create_proc_entry(leaf->name, mask, sg_proc_sgp);
2680                 if (pdep) {
2681                         leaf->fops->owner = THIS_MODULE,
2682                         leaf->fops->read = seq_read,
2683                         leaf->fops->llseek = seq_lseek,
2684                         pdep->proc_fops = leaf->fops;
2685                 }
2686         }
2687         return 0;
2688 }
2689
2690 static void
2691 sg_proc_cleanup(void)
2692 {
2693         int k;
2694         int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2695
2696         if (!sg_proc_sgp)
2697                 return;
2698         for (k = 0; k < num_leaves; ++k)
2699                 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2700         remove_proc_entry(sg_proc_sg_dirname, NULL);
2701 }
2702
2703
2704 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2705 {
2706         seq_printf(s, "%d\n", *((int *)s->private));
2707         return 0;
2708 }
2709
2710 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2711 {
2712         return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2713 }
2714
2715 static ssize_t
2716 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2717                    size_t count, loff_t *off)
2718 {
2719         int num;
2720         char buff[11];
2721
2722         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2723                 return -EACCES;
2724         num = (count < 10) ? count : 10;
2725         if (copy_from_user(buff, buffer, num))
2726                 return -EFAULT;
2727         buff[num] = '\0';
2728         sg_allow_dio = simple_strtoul(buff, NULL, 10) ? 1 : 0;
2729         return count;
2730 }
2731
2732 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2733 {
2734         return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2735 }
2736
2737 static ssize_t
2738 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2739                      size_t count, loff_t *off)
2740 {
2741         int num;
2742         unsigned long k = ULONG_MAX;
2743         char buff[11];
2744
2745         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2746                 return -EACCES;
2747         num = (count < 10) ? count : 10;
2748         if (copy_from_user(buff, buffer, num))
2749                 return -EFAULT;
2750         buff[num] = '\0';
2751         k = simple_strtoul(buff, NULL, 10);
2752         if (k <= 1048576) {     /* limit "big buff" to 1 MB */
2753                 sg_big_buff = k;
2754                 return count;
2755         }
2756         return -ERANGE;
2757 }
2758
2759 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2760 {
2761         seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2762                    sg_version_date);
2763         return 0;
2764 }
2765
2766 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2767 {
2768         return single_open(file, sg_proc_seq_show_version, NULL);
2769 }
2770
2771 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2772 {
2773         seq_printf(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\t"
2774                    "online\n");
2775         return 0;
2776 }
2777
2778 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2779 {
2780         return single_open(file, sg_proc_seq_show_devhdr, NULL);
2781 }
2782
2783 struct sg_proc_deviter {
2784         loff_t  index;
2785         size_t  max;
2786 };
2787
2788 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2789 {
2790         struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2791
2792         s->private = it;
2793         if (! it)
2794                 return NULL;
2795
2796         it->index = *pos;
2797         it->max = sg_last_dev();
2798         if (it->index >= it->max)
2799                 return NULL;
2800         return it;
2801 }
2802
2803 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2804 {
2805         struct sg_proc_deviter * it = s->private;
2806
2807         *pos = ++it->index;
2808         return (it->index < it->max) ? it : NULL;
2809 }
2810
2811 static void dev_seq_stop(struct seq_file *s, void *v)
2812 {
2813         kfree(s->private);
2814 }
2815
2816 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2817 {
2818         return seq_open(file, &dev_seq_ops);
2819 }
2820
2821 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2822 {
2823         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2824         Sg_device *sdp;
2825         struct scsi_device *scsidp;
2826
2827         sdp = it ? sg_get_dev(it->index) : NULL;
2828         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2829                 seq_printf(s, "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n",
2830                               scsidp->host->host_no, scsidp->channel,
2831                               scsidp->id, scsidp->lun, (int) scsidp->type,
2832                               1,
2833                               (int) scsidp->queue_depth,
2834                               (int) scsidp->device_busy,
2835                               (int) scsi_device_online(scsidp));
2836         else
2837                 seq_printf(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2838         return 0;
2839 }
2840
2841 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2842 {
2843         return seq_open(file, &devstrs_seq_ops);
2844 }
2845
2846 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2847 {
2848         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2849         Sg_device *sdp;
2850         struct scsi_device *scsidp;
2851
2852         sdp = it ? sg_get_dev(it->index) : NULL;
2853         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2854                 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2855                            scsidp->vendor, scsidp->model, scsidp->rev);
2856         else
2857                 seq_printf(s, "<no active device>\n");
2858         return 0;
2859 }
2860
2861 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2862 {
2863         int k, m, new_interface, blen, usg;
2864         Sg_request *srp;
2865         Sg_fd *fp;
2866         const sg_io_hdr_t *hp;
2867         const char * cp;
2868         unsigned int ms;
2869
2870         for (k = 0; (fp = sg_get_nth_sfp(sdp, k)); ++k) {
2871                 seq_printf(s, "   FD(%d): timeout=%dms bufflen=%d "
2872                            "(res)sgat=%d low_dma=%d\n", k + 1,
2873                            jiffies_to_msecs(fp->timeout),
2874                            fp->reserve.bufflen,
2875                            (int) fp->reserve.k_use_sg,
2876                            (int) fp->low_dma);
2877                 seq_printf(s, "   cmd_q=%d f_packid=%d k_orphan=%d closed=%d\n",
2878                            (int) fp->cmd_q, (int) fp->force_packid,
2879                            (int) fp->keep_orphan, (int) fp->closed);
2880                 for (m = 0; (srp = sg_get_nth_request(fp, m)); ++m) {
2881                         hp = &srp->header;
2882                         new_interface = (hp->interface_id == '\0') ? 0 : 1;
2883                         if (srp->res_used) {
2884                                 if (new_interface &&
2885                                     (SG_FLAG_MMAP_IO & hp->flags))
2886                                         cp = "     mmap>> ";
2887                                 else
2888                                         cp = "     rb>> ";
2889                         } else {
2890                                 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2891                                         cp = "     dio>> ";
2892                                 else
2893                                         cp = "     ";
2894                         }
2895                         seq_printf(s, cp);
2896                         blen = srp->data.bufflen;
2897                         usg = srp->data.k_use_sg;
2898                         seq_printf(s, srp->done ?
2899                                    ((1 == srp->done) ?  "rcv:" : "fin:")
2900                                    : "act:");
2901                         seq_printf(s, " id=%d blen=%d",
2902                                    srp->header.pack_id, blen);
2903                         if (srp->done)
2904                                 seq_printf(s, " dur=%d", hp->duration);
2905                         else {
2906                                 ms = jiffies_to_msecs(jiffies);
2907                                 seq_printf(s, " t_o/elap=%d/%d",
2908                                         (new_interface ? hp->timeout :
2909                                                   jiffies_to_msecs(fp->timeout)),
2910                                         (ms > hp->duration ? ms - hp->duration : 0));
2911                         }
2912                         seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2913                                    (int) srp->data.cmd_opcode);
2914                 }
2915                 if (0 == m)
2916                         seq_printf(s, "     No requests active\n");
2917         }
2918 }
2919
2920 static int sg_proc_open_debug(struct inode *inode, struct file *file)
2921 {
2922         return seq_open(file, &debug_seq_ops);
2923 }
2924
2925 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2926 {
2927         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2928         Sg_device *sdp;
2929
2930         if (it && (0 == it->index)) {
2931                 seq_printf(s, "max_active_device=%d(origin 1)\n",
2932                            (int)it->max);
2933                 seq_printf(s, " def_reserved_size=%d\n", sg_big_buff);
2934         }
2935         sdp = it ? sg_get_dev(it->index) : NULL;
2936         if (sdp) {
2937                 struct scsi_device *scsidp = sdp->device;
2938
2939                 if (NULL == scsidp) {
2940                         seq_printf(s, "device %d detached ??\n",
2941                                    (int)it->index);
2942                         return 0;
2943                 }
2944
2945                 if (sg_get_nth_sfp(sdp, 0)) {
2946                         seq_printf(s, " >>> device=%s ",
2947                                 sdp->disk->disk_name);
2948                         if (sdp->detached)
2949                                 seq_printf(s, "detached pending close ");
2950                         else
2951                                 seq_printf
2952                                     (s, "scsi%d chan=%d id=%d lun=%d   em=%d",
2953                                      scsidp->host->host_no,
2954                                      scsidp->channel, scsidp->id,
2955                                      scsidp->lun,
2956                                      scsidp->host->hostt->emulated);
2957                         seq_printf(s, " sg_tablesize=%d excl=%d\n",
2958                                    sdp->sg_tablesize, sdp->exclude);
2959                 }
2960                 sg_proc_debug_helper(s, sdp);
2961         }
2962         return 0;
2963 }
2964
2965 #endif                          /* CONFIG_SCSI_PROC_FS */
2966
2967 module_init(init_sg);
2968 module_exit(exit_sg);