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, struct file *file,
 186                         const char __user *buf, size_t count, int blocking,
 187                         int read_only, Sg_request **o_srp);
 188 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
 189                            unsigned char *cmnd, int timeout, int blocking);
 190 static int sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
 191                       int wr_xf, int *countp, unsigned char __user **up);
 192 static int sg_write_xfer(Sg_request * srp);
 193 static int sg_read_xfer(Sg_request * srp);
 194 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
 195 static void sg_remove_scat(Sg_scatter_hold * schp);
 196 static void sg_build_reserve(Sg_fd * sfp, int req_size);
 197 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
 198 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
 199 static struct page *sg_page_malloc(int rqSz, int lowDma, int *retSzp);
 200 static void sg_page_free(struct page *page, int size);
 201 static Sg_fd *sg_add_sfp(Sg_device * sdp, int dev);
 202 static int sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
 203 static void __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
 204 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
 205 static Sg_request *sg_add_request(Sg_fd * sfp);
 206 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
 207 static int sg_res_in_use(Sg_fd * sfp);
 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, filp, 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, struct file *file, const char __user *buf,
 625                  size_t count, int blocking, int read_only,
 626                  Sg_request **o_srp)
 627 {
 628         int k;
 629         Sg_request *srp;
 630         sg_io_hdr_t *hp;
 631         unsigned char cmnd[MAX_COMMAND_SIZE];
 632         int timeout;
 633         unsigned long ul_timeout;
 634
 635         if (count < SZ_SG_IO_HDR)
 636                 return -EINVAL;
 637         if (!access_ok(VERIFY_READ, buf, count))
 638                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 639
 640         sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
 641         if (!(srp = sg_add_request(sfp))) {
 642                 SCSI_LOG_TIMEOUT(1, printk("sg_new_write: queue full\n"));
 643                 return -EDOM;
 644         }
 645         hp = &srp->header;
 646         if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
 647                 sg_remove_request(sfp, srp);
 648                 return -EFAULT;
 649         }
 650         if (hp->interface_id != 'S') {
 651                 sg_remove_request(sfp, srp);
 652                 return -ENOSYS;
 653         }
 654         if (hp->flags & SG_FLAG_MMAP_IO) {
 655                 if (hp->dxfer_len > sfp->reserve.bufflen) {
 656                         sg_remove_request(sfp, srp);
 657                         return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
 658                 }
 659                 if (hp->flags & SG_FLAG_DIRECT_IO) {
 660                         sg_remove_request(sfp, srp);
 661                         return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
 662                 }
 663                 if (sg_res_in_use(sfp)) {
 664                         sg_remove_request(sfp, srp);
 665                         return -EBUSY;  /* reserve buffer already being used */
 666                 }
 667         }
 668         ul_timeout = msecs_to_jiffies(srp->header.timeout);
 669         timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
 670         if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
 671                 sg_remove_request(sfp, srp);
 672                 return -EMSGSIZE;
 673         }
 674         if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
 675                 sg_remove_request(sfp, srp);
 676                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 677         }
 678         if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
 679                 sg_remove_request(sfp, srp);
 680                 return -EFAULT;
 681         }
 682         if (read_only && !blk_verify_command(file, cmnd)) {
 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, filp, 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 (!blk_verify_command(filp, &opcode))
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_drvdata(sg_sysfs_class,
1445                                                         cl_dev->parent,
1446                                                         MKDEV(SCSI_GENERIC_MAJOR,
1447                                                               sdp->index),
1448                                                         sdp,
1449                                                         "%s", disk->disk_name);
1450                 if (IS_ERR(sg_class_member)) {
1451                         printk(KERN_ERR "sg_add: "
1452                                "device_create failed\n");
1453                         error = PTR_ERR(sg_class_member);
1454                         goto cdev_add_err;
1455                 }
1456                 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1457                                           &sg_class_member->kobj, "generic");
1458                 if (error)
1459                         printk(KERN_ERR "sg_add: unable to make symlink "
1460                                         "'generic' back to sg%d\n", sdp->index);
1461         } else
1462                 printk(KERN_WARNING "sg_add: sg_sys Invalid\n");
1463
1464         sdev_printk(KERN_NOTICE, scsidp,
1465                     "Attached scsi generic sg%d type %d\n", sdp->index,
1466                     scsidp->type);
1467
1468         dev_set_drvdata(cl_dev, sdp);
1469
1470         return 0;
1471
1472 cdev_add_err:
1473         write_lock_irqsave(&sg_index_lock, iflags);
1474         idr_remove(&sg_index_idr, sdp->index);
1475         write_unlock_irqrestore(&sg_index_lock, iflags);
1476         kfree(sdp);
1477
1478 out:
1479         put_disk(disk);
1480         if (cdev)
1481                 cdev_del(cdev);
1482         return error;
1483 }
1484
1485 static void
1486 sg_remove(struct device *cl_dev, struct class_interface *cl_intf)
1487 {
1488         struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1489         Sg_device *sdp = dev_get_drvdata(cl_dev);
1490         unsigned long iflags;
1491         Sg_fd *sfp;
1492         Sg_fd *tsfp;
1493         Sg_request *srp;
1494         Sg_request *tsrp;
1495         int delay;
1496
1497         if (!sdp)
1498                 return;
1499
1500         delay = 0;
1501         write_lock_irqsave(&sg_index_lock, iflags);
1502         if (sdp->headfp) {
1503                 sdp->detached = 1;
1504                 for (sfp = sdp->headfp; sfp; sfp = tsfp) {
1505                         tsfp = sfp->nextfp;
1506                         for (srp = sfp->headrp; srp; srp = tsrp) {
1507                                 tsrp = srp->nextrp;
1508                                 if (sfp->closed || (0 == sg_srp_done(srp, sfp)))
1509                                         sg_finish_rem_req(srp);
1510                         }
1511                         if (sfp->closed) {
1512                                 scsi_device_put(sdp->device);
1513                                 __sg_remove_sfp(sdp, sfp);
1514                         } else {
1515                                 delay = 1;
1516                                 wake_up_interruptible(&sfp->read_wait);
1517                                 kill_fasync(&sfp->async_qp, SIGPOLL,
1518                                             POLL_HUP);
1519                         }
1520                 }
1521                 SCSI_LOG_TIMEOUT(3, printk("sg_remove: dev=%d, dirty\n", sdp->index));
1522                 if (NULL == sdp->headfp) {
1523                         idr_remove(&sg_index_idr, sdp->index);
1524                 }
1525         } else {        /* nothing active, simple case */
1526                 SCSI_LOG_TIMEOUT(3, printk("sg_remove: dev=%d\n", sdp->index));
1527                 idr_remove(&sg_index_idr, sdp->index);
1528         }
1529         write_unlock_irqrestore(&sg_index_lock, iflags);
1530
1531         sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1532         device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1533         cdev_del(sdp->cdev);
1534         sdp->cdev = NULL;
1535         put_disk(sdp->disk);
1536         sdp->disk = NULL;
1537         if (NULL == sdp->headfp)
1538                 kfree(sdp);
1539
1540         if (delay)
1541                 msleep(10);     /* dirty detach so delay device destruction */
1542 }
1543
1544 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1545 module_param_named(def_reserved_size, def_reserved_size, int,
1546                    S_IRUGO | S_IWUSR);
1547 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1548
1549 MODULE_AUTHOR("Douglas Gilbert");
1550 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1551 MODULE_LICENSE("GPL");
1552 MODULE_VERSION(SG_VERSION_STR);
1553 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1554
1555 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1556                 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1557 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1558 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1559
1560 static int __init
1561 init_sg(void)
1562 {
1563         int rc;
1564
1565         if (scatter_elem_sz < PAGE_SIZE) {
1566                 scatter_elem_sz = PAGE_SIZE;
1567                 scatter_elem_sz_prev = scatter_elem_sz;
1568         }
1569         if (def_reserved_size >= 0)
1570                 sg_big_buff = def_reserved_size;
1571         else
1572                 def_reserved_size = sg_big_buff;
1573
1574         rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1575                                     SG_MAX_DEVS, "sg");
1576         if (rc)
1577                 return rc;
1578         sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1579         if ( IS_ERR(sg_sysfs_class) ) {
1580                 rc = PTR_ERR(sg_sysfs_class);
1581                 goto err_out;
1582         }
1583         sg_sysfs_valid = 1;
1584         rc = scsi_register_interface(&sg_interface);
1585         if (0 == rc) {
1586 #ifdef CONFIG_SCSI_PROC_FS
1587                 sg_proc_init();
1588 #endif                          /* CONFIG_SCSI_PROC_FS */
1589                 return 0;
1590         }
1591         class_destroy(sg_sysfs_class);
1592 err_out:
1593         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1594         return rc;
1595 }
1596
1597 static void __exit
1598 exit_sg(void)
1599 {
1600 #ifdef CONFIG_SCSI_PROC_FS
1601         sg_proc_cleanup();
1602 #endif                          /* CONFIG_SCSI_PROC_FS */
1603         scsi_unregister_interface(&sg_interface);
1604         class_destroy(sg_sysfs_class);
1605         sg_sysfs_valid = 0;
1606         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1607                                  SG_MAX_DEVS);
1608         idr_destroy(&sg_index_idr);
1609 }
1610
1611 static int
1612 sg_start_req(Sg_request * srp)
1613 {
1614         int res;
1615         Sg_fd *sfp = srp->parentfp;
1616         sg_io_hdr_t *hp = &srp->header;
1617         int dxfer_len = (int) hp->dxfer_len;
1618         int dxfer_dir = hp->dxfer_direction;
1619         Sg_scatter_hold *req_schp = &srp->data;
1620         Sg_scatter_hold *rsv_schp = &sfp->reserve;
1621
1622         SCSI_LOG_TIMEOUT(4, printk("sg_start_req: dxfer_len=%d\n", dxfer_len));
1623         if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1624                 return 0;
1625         if (sg_allow_dio && (hp->flags & SG_FLAG_DIRECT_IO) &&
1626             (dxfer_dir != SG_DXFER_UNKNOWN) && (0 == hp->iovec_count) &&
1627             (!sfp->parentdp->device->host->unchecked_isa_dma)) {
1628                 res = sg_build_direct(srp, sfp, dxfer_len);
1629                 if (res <= 0)   /* -ve -> error, 0 -> done, 1 -> try indirect */
1630                         return res;
1631         }
1632         if ((!sg_res_in_use(sfp)) && (dxfer_len <= rsv_schp->bufflen))
1633                 sg_link_reserve(sfp, srp, dxfer_len);
1634         else {
1635                 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1636                 if (res) {
1637                         sg_remove_scat(req_schp);
1638                         return res;
1639                 }
1640         }
1641         return 0;
1642 }
1643
1644 static void
1645 sg_finish_rem_req(Sg_request * srp)
1646 {
1647         Sg_fd *sfp = srp->parentfp;
1648         Sg_scatter_hold *req_schp = &srp->data;
1649
1650         SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n", (int) srp->res_used));
1651         if (srp->res_used)
1652                 sg_unlink_reserve(sfp, srp);
1653         else
1654                 sg_remove_scat(req_schp);
1655         sg_remove_request(sfp, srp);
1656 }
1657
1658 static int
1659 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1660 {
1661         int sg_bufflen = tablesize * sizeof(struct scatterlist);
1662         gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1663
1664         /*
1665          * TODO: test without low_dma, we should not need it since
1666          * the block layer will bounce the buffer for us
1667          *
1668          * XXX(hch): we shouldn't need GFP_DMA for the actual S/G list.
1669          */
1670         if (sfp->low_dma)
1671                  gfp_flags |= GFP_DMA;
1672         schp->buffer = kzalloc(sg_bufflen, gfp_flags);
1673         if (!schp->buffer)
1674                 return -ENOMEM;
1675         sg_init_table(schp->buffer, tablesize);
1676         schp->sglist_len = sg_bufflen;
1677         return tablesize;       /* number of scat_gath elements allocated */
1678 }
1679
1680 #ifdef SG_ALLOW_DIO_CODE
1681 /* vvvvvvvv  following code borrowed from st driver's direct IO vvvvvvvvv */
1682         /* TODO: hopefully we can use the generic block layer code */
1683
1684 /* Pin down user pages and put them into a scatter gather list. Returns <= 0 if
1685    - mapping of all pages not successful
1686    (i.e., either completely successful or fails)
1687 */
1688 static int
1689 st_map_user_pages(struct scatterlist *sgl, const unsigned int max_pages,
1690                   unsigned long uaddr, size_t count, int rw)
1691 {
1692         unsigned long end = (uaddr + count + PAGE_SIZE - 1) >> PAGE_SHIFT;
1693         unsigned long start = uaddr >> PAGE_SHIFT;
1694         const int nr_pages = end - start;
1695         int res, i, j;
1696         struct page **pages;
1697
1698         /* User attempted Overflow! */
1699         if ((uaddr + count) < uaddr)
1700                 return -EINVAL;
1701
1702         /* Too big */
1703         if (nr_pages > max_pages)
1704                 return -ENOMEM;
1705
1706         /* Hmm? */
1707         if (count == 0)
1708                 return 0;
1709
1710         if ((pages = kmalloc(max_pages * sizeof(*pages), GFP_ATOMIC)) == NULL)
1711                 return -ENOMEM;
1712
1713         /* Try to fault in all of the necessary pages */
1714         down_read(&current->mm->mmap_sem);
1715         /* rw==READ means read from drive, write into memory area */
1716         res = get_user_pages(
1717                 current,
1718                 current->mm,
1719                 uaddr,
1720                 nr_pages,
1721                 rw == READ,
1722                 0, /* don't force */
1723                 pages,
1724                 NULL);
1725         up_read(&current->mm->mmap_sem);
1726
1727         /* Errors and no page mapped should return here */
1728         if (res < nr_pages)
1729                 goto out_unmap;
1730
1731         for (i=0; i < nr_pages; i++) {
1732                 /* FIXME: flush superflous for rw==READ,
1733                  * probably wrong function for rw==WRITE
1734                  */
1735                 flush_dcache_page(pages[i]);
1736                 /* ?? Is locking needed? I don't think so */
1737                 /* if (TestSetPageLocked(pages[i]))
1738                    goto out_unlock; */
1739         }
1740
1741         sg_set_page(sgl, pages[0], 0, uaddr & ~PAGE_MASK);
1742         if (nr_pages > 1) {
1743                 sgl[0].length = PAGE_SIZE - sgl[0].offset;
1744                 count -= sgl[0].length;
1745                 for (i=1; i < nr_pages ; i++)
1746                         sg_set_page(&sgl[i], pages[i], count < PAGE_SIZE ? count : PAGE_SIZE, 0);
1747         }
1748         else {
1749                 sgl[0].length = count;
1750         }
1751
1752         kfree(pages);
1753         return nr_pages;
1754
1755  out_unmap:
1756         if (res > 0) {
1757                 for (j=0; j < res; j++)
1758                         page_cache_release(pages[j]);
1759                 res = 0;
1760         }
1761         kfree(pages);
1762         return res;
1763 }
1764
1765
1766 /* And unmap them... */
1767 static int
1768 st_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_pages,
1769                     int dirtied)
1770 {
1771         int i;
1772
1773         for (i=0; i < nr_pages; i++) {
1774                 struct page *page = sg_page(&sgl[i]);
1775
1776                 if (dirtied)
1777                         SetPageDirty(page);
1778                 /* unlock_page(page); */
1779                 /* FIXME: cache flush missing for rw==READ
1780                  * FIXME: call the correct reference counting function
1781                  */
1782                 page_cache_release(page);
1783         }
1784
1785         return 0;
1786 }
1787
1788 /* ^^^^^^^^  above code borrowed from st driver's direct IO ^^^^^^^^^ */
1789 #endif
1790
1791
1792 /* Returns: -ve -> error, 0 -> done, 1 -> try indirect */
1793 static int
1794 sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len)
1795 {
1796 #ifdef SG_ALLOW_DIO_CODE
1797         sg_io_hdr_t *hp = &srp->header;
1798         Sg_scatter_hold *schp = &srp->data;
1799         int sg_tablesize = sfp->parentdp->sg_tablesize;
1800         int mx_sc_elems, res;
1801         struct scsi_device *sdev = sfp->parentdp->device;
1802
1803         if (((unsigned long)hp->dxferp &
1804                         queue_dma_alignment(sdev->request_queue)) != 0)
1805                 return 1;
1806
1807         mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1808         if (mx_sc_elems <= 0) {
1809                 return 1;
1810         }
1811         res = st_map_user_pages(schp->buffer, mx_sc_elems,
1812                                 (unsigned long)hp->dxferp, dxfer_len,
1813                                 (SG_DXFER_TO_DEV == hp->dxfer_direction) ? 1 : 0);
1814         if (res <= 0) {
1815                 sg_remove_scat(schp);
1816                 return 1;
1817         }
1818         schp->k_use_sg = res;
1819         schp->dio_in_use = 1;
1820         hp->info |= SG_INFO_DIRECT_IO;
1821         return 0;
1822 #else
1823         return 1;
1824 #endif
1825 }
1826
1827 static int
1828 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1829 {
1830         struct scatterlist *sg;
1831         int ret_sz = 0, k, rem_sz, num, mx_sc_elems;
1832         int sg_tablesize = sfp->parentdp->sg_tablesize;
1833         int blk_size = buff_size;
1834         struct page *p = NULL;
1835
1836         if (blk_size < 0)
1837                 return -EFAULT;
1838         if (0 == blk_size)
1839                 ++blk_size;     /* don't know why */
1840 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1841         blk_size = (blk_size + SG_SECTOR_MSK) & (~SG_SECTOR_MSK);
1842         SCSI_LOG_TIMEOUT(4, printk("sg_build_indirect: buff_size=%d, blk_size=%d\n",
1843                                    buff_size, blk_size));
1844
1845         /* N.B. ret_sz carried into this block ... */
1846         mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1847         if (mx_sc_elems < 0)
1848                 return mx_sc_elems;     /* most likely -ENOMEM */
1849
1850         num = scatter_elem_sz;
1851         if (unlikely(num != scatter_elem_sz_prev)) {
1852                 if (num < PAGE_SIZE) {
1853                         scatter_elem_sz = PAGE_SIZE;
1854                         scatter_elem_sz_prev = PAGE_SIZE;
1855                 } else
1856                         scatter_elem_sz_prev = num;
1857         }
1858         for (k = 0, sg = schp->buffer, rem_sz = blk_size;
1859              (rem_sz > 0) && (k < mx_sc_elems);
1860              ++k, rem_sz -= ret_sz, sg = sg_next(sg)) {
1861
1862                 num = (rem_sz > scatter_elem_sz_prev) ?
1863                       scatter_elem_sz_prev : rem_sz;
1864                 p = sg_page_malloc(num, sfp->low_dma, &ret_sz);
1865                 if (!p)
1866                         return -ENOMEM;
1867
1868                 if (num == scatter_elem_sz_prev) {
1869                         if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1870                                 scatter_elem_sz = ret_sz;
1871                                 scatter_elem_sz_prev = ret_sz;
1872                         }
1873                 }
1874                 sg_set_page(sg, p, (ret_sz > num) ? num : ret_sz, 0);
1875
1876                 SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k=%d, num=%d, "
1877                                  "ret_sz=%d\n", k, num, ret_sz));
1878         }               /* end of for loop */
1879
1880         schp->k_use_sg = k;
1881         SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, "
1882                          "rem_sz=%d\n", k, rem_sz));
1883
1884         schp->bufflen = blk_size;
1885         if (rem_sz > 0) /* must have failed */
1886                 return -ENOMEM;
1887
1888         return 0;
1889 }
1890
1891 static int
1892 sg_write_xfer(Sg_request * srp)
1893 {
1894         sg_io_hdr_t *hp = &srp->header;
1895         Sg_scatter_hold *schp = &srp->data;
1896         struct scatterlist *sg = schp->buffer;
1897         int num_xfer = 0;
1898         int j, k, onum, usglen, ksglen, res;
1899         int iovec_count = (int) hp->iovec_count;
1900         int dxfer_dir = hp->dxfer_direction;
1901         unsigned char *p;
1902         unsigned char __user *up;
1903         int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
1904
1905         if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_TO_DEV == dxfer_dir) ||
1906             (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
1907                 num_xfer = (int) (new_interface ? hp->dxfer_len : hp->flags);
1908                 if (schp->bufflen < num_xfer)
1909                         num_xfer = schp->bufflen;
1910         }
1911         if ((num_xfer <= 0) || (schp->dio_in_use) ||
1912             (new_interface
1913              && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
1914                 return 0;
1915
1916         SCSI_LOG_TIMEOUT(4, printk("sg_write_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
1917                           num_xfer, iovec_count, schp->k_use_sg));
1918         if (iovec_count) {
1919                 onum = iovec_count;
1920                 if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum))
1921                         return -EFAULT;
1922         } else
1923                 onum = 1;
1924
1925         ksglen = sg->length;
1926         p = page_address(sg_page(sg));
1927         for (j = 0, k = 0; j < onum; ++j) {
1928                 res = sg_u_iovec(hp, iovec_count, j, 1, &usglen, &up);
1929                 if (res)
1930                         return res;
1931
1932                 for (; p; sg = sg_next(sg), ksglen = sg->length,
1933                      p = page_address(sg_page(sg))) {
1934                         if (usglen <= 0)
1935                                 break;
1936                         if (ksglen > usglen) {
1937                                 if (usglen >= num_xfer) {
1938                                         if (__copy_from_user(p, up, num_xfer))
1939                                                 return -EFAULT;
1940                                         return 0;
1941                                 }
1942                                 if (__copy_from_user(p, up, usglen))
1943                                         return -EFAULT;
1944                                 p += usglen;
1945                                 ksglen -= usglen;
1946                                 break;
1947                         } else {
1948                                 if (ksglen >= num_xfer) {
1949                                         if (__copy_from_user(p, up, num_xfer))
1950                                                 return -EFAULT;
1951                                         return 0;
1952                                 }
1953                                 if (__copy_from_user(p, up, ksglen))
1954                                         return -EFAULT;
1955                                 up += ksglen;
1956                                 usglen -= ksglen;
1957                         }
1958                         ++k;
1959                         if (k >= schp->k_use_sg)
1960                                 return 0;
1961                 }
1962         }
1963
1964         return 0;
1965 }
1966
1967 static int
1968 sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
1969            int wr_xf, int *countp, unsigned char __user **up)
1970 {
1971         int num_xfer = (int) hp->dxfer_len;
1972         unsigned char __user *p = hp->dxferp;
1973         int count;
1974
1975         if (0 == sg_num) {
1976                 if (wr_xf && ('\0' == hp->interface_id))
1977                         count = (int) hp->flags;        /* holds "old" input_size */
1978                 else
1979                         count = num_xfer;
1980         } else {
1981                 sg_iovec_t iovec;
1982                 if (__copy_from_user(&iovec, p + ind*SZ_SG_IOVEC, SZ_SG_IOVEC))
1983                         return -EFAULT;
1984                 p = iovec.iov_base;
1985                 count = (int) iovec.iov_len;
1986         }
1987         if (!access_ok(wr_xf ? VERIFY_READ : VERIFY_WRITE, p, count))
1988                 return -EFAULT;
1989         if (up)
1990                 *up = p;
1991         if (countp)
1992                 *countp = count;
1993         return 0;
1994 }
1995
1996 static void
1997 sg_remove_scat(Sg_scatter_hold * schp)
1998 {
1999         SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
2000         if (schp->buffer && (schp->sglist_len > 0)) {
2001                 struct scatterlist *sg = schp->buffer;
2002
2003                 if (schp->dio_in_use) {
2004 #ifdef SG_ALLOW_DIO_CODE
2005                         st_unmap_user_pages(sg, schp->k_use_sg, TRUE);
2006 #endif
2007                 } else {
2008                         int k;
2009
2010                         for (k = 0; (k < schp->k_use_sg) && sg_page(sg);
2011                              ++k, sg = sg_next(sg)) {
2012                                 SCSI_LOG_TIMEOUT(5, printk(
2013                                     "sg_remove_scat: k=%d, pg=0x%p, len=%d\n",
2014                                     k, sg_page(sg), sg->length));
2015                                 sg_page_free(sg_page(sg), sg->length);
2016                         }
2017                 }
2018                 kfree(schp->buffer);
2019         }
2020         memset(schp, 0, sizeof (*schp));
2021 }
2022
2023 static int
2024 sg_read_xfer(Sg_request * srp)
2025 {
2026         sg_io_hdr_t *hp = &srp->header;
2027         Sg_scatter_hold *schp = &srp->data;
2028         struct scatterlist *sg = schp->buffer;
2029         int num_xfer = 0;
2030         int j, k, onum, usglen, ksglen, res;
2031         int iovec_count = (int) hp->iovec_count;
2032         int dxfer_dir = hp->dxfer_direction;
2033         unsigned char *p;
2034         unsigned char __user *up;
2035         int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
2036
2037         if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_FROM_DEV == dxfer_dir)
2038             || (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
2039                 num_xfer = hp->dxfer_len;
2040                 if (schp->bufflen < num_xfer)
2041                         num_xfer = schp->bufflen;
2042         }
2043         if ((num_xfer <= 0) || (schp->dio_in_use) ||
2044             (new_interface
2045              && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
2046                 return 0;
2047
2048         SCSI_LOG_TIMEOUT(4, printk("sg_read_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
2049                           num_xfer, iovec_count, schp->k_use_sg));
2050         if (iovec_count) {
2051                 onum = iovec_count;
2052                 if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum))
2053                         return -EFAULT;
2054         } else
2055                 onum = 1;
2056
2057         p = page_address(sg_page(sg));
2058         ksglen = sg->length;
2059         for (j = 0, k = 0; j < onum; ++j) {
2060                 res = sg_u_iovec(hp, iovec_count, j, 0, &usglen, &up);
2061                 if (res)
2062                         return res;
2063
2064                 for (; p; sg = sg_next(sg), ksglen = sg->length,
2065                      p = page_address(sg_page(sg))) {
2066                         if (usglen <= 0)
2067                                 break;
2068                         if (ksglen > usglen) {
2069                                 if (usglen >= num_xfer) {
2070                                         if (__copy_to_user(up, p, num_xfer))
2071                                                 return -EFAULT;
2072                                         return 0;
2073                                 }
2074                                 if (__copy_to_user(up, p, usglen))
2075                                         return -EFAULT;
2076                                 p += usglen;
2077                                 ksglen -= usglen;
2078                                 break;
2079                         } else {
2080                                 if (ksglen >= num_xfer) {
2081                                         if (__copy_to_user(up, p, num_xfer))
2082                                                 return -EFAULT;
2083                                         return 0;
2084                                 }
2085                                 if (__copy_to_user(up, p, ksglen))
2086                                         return -EFAULT;
2087                                 up += ksglen;
2088                                 usglen -= ksglen;
2089                         }
2090                         ++k;
2091                         if (k >= schp->k_use_sg)
2092                                 return 0;
2093                 }
2094         }
2095
2096         return 0;
2097 }
2098
2099 static int
2100 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
2101 {
2102         Sg_scatter_hold *schp = &srp->data;
2103         struct scatterlist *sg = schp->buffer;
2104         int k, num;
2105
2106         SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n",
2107                                    num_read_xfer));
2108         if ((!outp) || (num_read_xfer <= 0))
2109                 return 0;
2110
2111         for (k = 0; (k < schp->k_use_sg) && sg_page(sg); ++k, sg = sg_next(sg)) {
2112                 num = sg->length;
2113                 if (num > num_read_xfer) {
2114                         if (__copy_to_user(outp, page_address(sg_page(sg)),
2115                                            num_read_xfer))
2116                                 return -EFAULT;
2117                         break;
2118                 } else {
2119                         if (__copy_to_user(outp, page_address(sg_page(sg)),
2120                                            num))
2121                                 return -EFAULT;
2122                         num_read_xfer -= num;
2123                         if (num_read_xfer <= 0)
2124                                 break;
2125                         outp += num;
2126                 }
2127         }
2128
2129         return 0;
2130 }
2131
2132 static void
2133 sg_build_reserve(Sg_fd * sfp, int req_size)
2134 {
2135         Sg_scatter_hold *schp = &sfp->reserve;
2136
2137         SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
2138         do {
2139                 if (req_size < PAGE_SIZE)
2140                         req_size = PAGE_SIZE;
2141                 if (0 == sg_build_indirect(schp, sfp, req_size))
2142                         return;
2143                 else
2144                         sg_remove_scat(schp);
2145                 req_size >>= 1; /* divide by 2 */
2146         } while (req_size > (PAGE_SIZE / 2));
2147 }
2148
2149 static void
2150 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2151 {
2152         Sg_scatter_hold *req_schp = &srp->data;
2153         Sg_scatter_hold *rsv_schp = &sfp->reserve;
2154         struct scatterlist *sg = rsv_schp->buffer;
2155         int k, num, rem;
2156
2157         srp->res_used = 1;
2158         SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
2159         rem = size;
2160
2161         for (k = 0; k < rsv_schp->k_use_sg; ++k, sg = sg_next(sg)) {
2162                 num = sg->length;
2163                 if (rem <= num) {
2164                         sfp->save_scat_len = num;
2165                         sg->length = rem;
2166                         req_schp->k_use_sg = k + 1;
2167                         req_schp->sglist_len = rsv_schp->sglist_len;
2168                         req_schp->buffer = rsv_schp->buffer;
2169
2170                         req_schp->bufflen = size;
2171                         req_schp->b_malloc_len = rsv_schp->b_malloc_len;
2172                         break;
2173                 } else
2174                         rem -= num;
2175         }
2176
2177         if (k >= rsv_schp->k_use_sg)
2178                 SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
2179 }
2180
2181 static void
2182 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2183 {
2184         Sg_scatter_hold *req_schp = &srp->data;
2185         Sg_scatter_hold *rsv_schp = &sfp->reserve;
2186
2187         SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->k_use_sg=%d\n",
2188                                    (int) req_schp->k_use_sg));
2189         if ((rsv_schp->k_use_sg > 0) && (req_schp->k_use_sg > 0)) {
2190                 struct scatterlist *sg = rsv_schp->buffer;
2191
2192                 if (sfp->save_scat_len > 0)
2193                         (sg + (req_schp->k_use_sg - 1))->length =
2194                             (unsigned) sfp->save_scat_len;
2195                 else
2196                         SCSI_LOG_TIMEOUT(1, printk ("sg_unlink_reserve: BAD save_scat_len\n"));
2197         }
2198         req_schp->k_use_sg = 0;
2199         req_schp->bufflen = 0;
2200         req_schp->buffer = NULL;
2201         req_schp->sglist_len = 0;
2202         sfp->save_scat_len = 0;
2203         srp->res_used = 0;
2204 }
2205
2206 static Sg_request *
2207 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2208 {
2209         Sg_request *resp;
2210         unsigned long iflags;
2211
2212         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2213         for (resp = sfp->headrp; resp; resp = resp->nextrp) {
2214                 /* look for requests that are ready + not SG_IO owned */
2215                 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2216                     ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2217                         resp->done = 2; /* guard against other readers */
2218                         break;
2219                 }
2220         }
2221         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2222         return resp;
2223 }
2224
2225 #ifdef CONFIG_SCSI_PROC_FS
2226 static Sg_request *
2227 sg_get_nth_request(Sg_fd * sfp, int nth)
2228 {
2229         Sg_request *resp;
2230         unsigned long iflags;
2231         int k;
2232
2233         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2234         for (k = 0, resp = sfp->headrp; resp && (k < nth);
2235              ++k, resp = resp->nextrp) ;
2236         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2237         return resp;
2238 }
2239 #endif
2240
2241 /* always adds to end of list */
2242 static Sg_request *
2243 sg_add_request(Sg_fd * sfp)
2244 {
2245         int k;
2246         unsigned long iflags;
2247         Sg_request *resp;
2248         Sg_request *rp = sfp->req_arr;
2249
2250         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2251         resp = sfp->headrp;
2252         if (!resp) {
2253                 memset(rp, 0, sizeof (Sg_request));
2254                 rp->parentfp = sfp;
2255                 resp = rp;
2256                 sfp->headrp = resp;
2257         } else {
2258                 if (0 == sfp->cmd_q)
2259                         resp = NULL;    /* command queuing disallowed */
2260                 else {
2261                         for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2262                                 if (!rp->parentfp)
2263                                         break;
2264                         }
2265                         if (k < SG_MAX_QUEUE) {
2266                                 memset(rp, 0, sizeof (Sg_request));
2267                                 rp->parentfp = sfp;
2268                                 while (resp->nextrp)
2269                                         resp = resp->nextrp;
2270                                 resp->nextrp = rp;
2271                                 resp = rp;
2272                         } else
2273                                 resp = NULL;
2274                 }
2275         }
2276         if (resp) {
2277                 resp->nextrp = NULL;
2278                 resp->header.duration = jiffies_to_msecs(jiffies);
2279         }
2280         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2281         return resp;
2282 }
2283
2284 /* Return of 1 for found; 0 for not found */
2285 static int
2286 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2287 {
2288         Sg_request *prev_rp;
2289         Sg_request *rp;
2290         unsigned long iflags;
2291         int res = 0;
2292
2293         if ((!sfp) || (!srp) || (!sfp->headrp))
2294                 return res;
2295         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2296         prev_rp = sfp->headrp;
2297         if (srp == prev_rp) {
2298                 sfp->headrp = prev_rp->nextrp;
2299                 prev_rp->parentfp = NULL;
2300                 res = 1;
2301         } else {
2302                 while ((rp = prev_rp->nextrp)) {
2303                         if (srp == rp) {
2304                                 prev_rp->nextrp = rp->nextrp;
2305                                 rp->parentfp = NULL;
2306                                 res = 1;
2307                                 break;
2308                         }
2309                         prev_rp = rp;
2310                 }
2311         }
2312         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2313         return res;
2314 }
2315
2316 #ifdef CONFIG_SCSI_PROC_FS
2317 static Sg_fd *
2318 sg_get_nth_sfp(Sg_device * sdp, int nth)
2319 {
2320         Sg_fd *resp;
2321         unsigned long iflags;
2322         int k;
2323
2324         read_lock_irqsave(&sg_index_lock, iflags);
2325         for (k = 0, resp = sdp->headfp; resp && (k < nth);
2326              ++k, resp = resp->nextfp) ;
2327         read_unlock_irqrestore(&sg_index_lock, iflags);
2328         return resp;
2329 }
2330 #endif
2331
2332 static Sg_fd *
2333 sg_add_sfp(Sg_device * sdp, int dev)
2334 {
2335         Sg_fd *sfp;
2336         unsigned long iflags;
2337         int bufflen;
2338
2339         sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2340         if (!sfp)
2341                 return NULL;
2342
2343         init_waitqueue_head(&sfp->read_wait);
2344         rwlock_init(&sfp->rq_list_lock);
2345
2346         sfp->timeout = SG_DEFAULT_TIMEOUT;
2347         sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2348         sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2349         sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
2350             sdp->device->host->unchecked_isa_dma : 1;
2351         sfp->cmd_q = SG_DEF_COMMAND_Q;
2352         sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2353         sfp->parentdp = sdp;
2354         write_lock_irqsave(&sg_index_lock, iflags);
2355         if (!sdp->headfp)
2356                 sdp->headfp = sfp;
2357         else {                  /* add to tail of existing list */
2358                 Sg_fd *pfp = sdp->headfp;
2359                 while (pfp->nextfp)
2360                         pfp = pfp->nextfp;
2361                 pfp->nextfp = sfp;
2362         }
2363         write_unlock_irqrestore(&sg_index_lock, iflags);
2364         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));
2365         if (unlikely(sg_big_buff != def_reserved_size))
2366                 sg_big_buff = def_reserved_size;
2367
2368         bufflen = min_t(int, sg_big_buff,
2369                         sdp->device->request_queue->max_sectors * 512);
2370         sg_build_reserve(sfp, bufflen);
2371         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp:   bufflen=%d, k_use_sg=%d\n",
2372                            sfp->reserve.bufflen, sfp->reserve.k_use_sg));
2373         return sfp;
2374 }
2375
2376 static void
2377 __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2378 {
2379         Sg_fd *fp;
2380         Sg_fd *prev_fp;
2381
2382         prev_fp = sdp->headfp;
2383         if (sfp == prev_fp)
2384                 sdp->headfp = prev_fp->nextfp;
2385         else {
2386                 while ((fp = prev_fp->nextfp)) {
2387                         if (sfp == fp) {
2388                                 prev_fp->nextfp = fp->nextfp;
2389                                 break;
2390                         }
2391                         prev_fp = fp;
2392                 }
2393         }
2394         if (sfp->reserve.bufflen > 0) {
2395                 SCSI_LOG_TIMEOUT(6,
2396                         printk("__sg_remove_sfp:    bufflen=%d, k_use_sg=%d\n",
2397                         (int) sfp->reserve.bufflen, (int) sfp->reserve.k_use_sg));
2398                 sg_remove_scat(&sfp->reserve);
2399         }
2400         sfp->parentdp = NULL;
2401         SCSI_LOG_TIMEOUT(6, printk("__sg_remove_sfp:    sfp=0x%p\n", sfp));
2402         kfree(sfp);
2403 }
2404
2405 /* Returns 0 in normal case, 1 when detached and sdp object removed */
2406 static int
2407 sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2408 {
2409         Sg_request *srp;
2410         Sg_request *tsrp;
2411         int dirty = 0;
2412         int res = 0;
2413
2414         for (srp = sfp->headrp; srp; srp = tsrp) {
2415                 tsrp = srp->nextrp;
2416                 if (sg_srp_done(srp, sfp))
2417                         sg_finish_rem_req(srp);
2418                 else
2419                         ++dirty;
2420         }
2421         if (0 == dirty) {
2422                 unsigned long iflags;
2423
2424                 write_lock_irqsave(&sg_index_lock, iflags);
2425                 __sg_remove_sfp(sdp, sfp);
2426                 if (sdp->detached && (NULL == sdp->headfp)) {
2427                         idr_remove(&sg_index_idr, sdp->index);
2428                         kfree(sdp);
2429                         res = 1;
2430                 }
2431                 write_unlock_irqrestore(&sg_index_lock, iflags);
2432         } else {
2433                 /* MOD_INC's to inhibit unloading sg and associated adapter driver */
2434                 /* only bump the access_count if we actually succeeded in
2435                  * throwing another counter on the host module */
2436                 scsi_device_get(sdp->device);   /* XXX: retval ignored? */
2437                 sfp->closed = 1;        /* flag dirty state on this fd */
2438                 SCSI_LOG_TIMEOUT(1, printk("sg_remove_sfp: worrisome, %d writes pending\n",
2439                                   dirty));
2440         }
2441         return res;
2442 }
2443
2444 static int
2445 sg_res_in_use(Sg_fd * sfp)
2446 {
2447         const Sg_request *srp;
2448         unsigned long iflags;
2449
2450         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2451         for (srp = sfp->headrp; srp; srp = srp->nextrp)
2452                 if (srp->res_used)
2453                         break;
2454         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2455         return srp ? 1 : 0;
2456 }
2457
2458 /* The size fetched (value output via retSzp) set when non-NULL return */
2459 static struct page *
2460 sg_page_malloc(int rqSz, int lowDma, int *retSzp)
2461 {
2462         struct page *resp = NULL;
2463         gfp_t page_mask;
2464         int order, a_size;
2465         int resSz;
2466
2467         if ((rqSz <= 0) || (NULL == retSzp))
2468                 return resp;
2469
2470         if (lowDma)
2471                 page_mask = GFP_ATOMIC | GFP_DMA | __GFP_COMP | __GFP_NOWARN;
2472         else
2473                 page_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
2474
2475         for (order = 0, a_size = PAGE_SIZE; a_size < rqSz;
2476              order++, a_size <<= 1) ;
2477         resSz = a_size;         /* rounded up if necessary */
2478         resp = alloc_pages(page_mask, order);
2479         while ((!resp) && order) {
2480                 --order;
2481                 a_size >>= 1;   /* divide by 2, until PAGE_SIZE */
2482                 resp =  alloc_pages(page_mask, order);  /* try half */
2483                 resSz = a_size;
2484         }
2485         if (resp) {
2486                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2487                         memset(page_address(resp), 0, resSz);
2488                 *retSzp = resSz;
2489         }
2490         return resp;
2491 }
2492
2493 static void
2494 sg_page_free(struct page *page, int size)
2495 {
2496         int order, a_size;
2497
2498         if (!page)
2499                 return;
2500         for (order = 0, a_size = PAGE_SIZE; a_size < size;
2501              order++, a_size <<= 1) ;
2502         __free_pages(page, order);
2503 }
2504
2505 #ifdef CONFIG_SCSI_PROC_FS
2506 static int
2507 sg_idr_max_id(int id, void *p, void *data)
2508 {
2509         int *k = data;
2510
2511         if (*k < id)
2512                 *k = id;
2513
2514         return 0;
2515 }
2516
2517 static int
2518 sg_last_dev(void)
2519 {
2520         int k = -1;
2521         unsigned long iflags;
2522
2523         read_lock_irqsave(&sg_index_lock, iflags);
2524         idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2525         read_unlock_irqrestore(&sg_index_lock, iflags);
2526         return k + 1;           /* origin 1 */
2527 }
2528 #endif
2529
2530 static Sg_device *
2531 sg_get_dev(int dev)
2532 {
2533         Sg_device *sdp;
2534         unsigned long iflags;
2535
2536         read_lock_irqsave(&sg_index_lock, iflags);
2537         sdp = idr_find(&sg_index_idr, dev);
2538         read_unlock_irqrestore(&sg_index_lock, iflags);
2539
2540         return sdp;
2541 }
2542
2543 #ifdef CONFIG_SCSI_PROC_FS
2544
2545 static struct proc_dir_entry *sg_proc_sgp = NULL;
2546
2547 static char sg_proc_sg_dirname[] = "scsi/sg";
2548
2549 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2550
2551 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2552 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2553                                   size_t count, loff_t *off);
2554 static struct file_operations adio_fops = {
2555         /* .owner, .read and .llseek added in sg_proc_init() */
2556         .open = sg_proc_single_open_adio,
2557         .write = sg_proc_write_adio,
2558         .release = single_release,
2559 };
2560
2561 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2562 static ssize_t sg_proc_write_dressz(struct file *filp,
2563                 const char __user *buffer, size_t count, loff_t *off);
2564 static struct file_operations dressz_fops = {
2565         .open = sg_proc_single_open_dressz,
2566         .write = sg_proc_write_dressz,
2567         .release = single_release,
2568 };
2569
2570 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2571 static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2572 static struct file_operations version_fops = {
2573         .open = sg_proc_single_open_version,
2574         .release = single_release,
2575 };
2576
2577 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2578 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2579 static struct file_operations devhdr_fops = {
2580         .open = sg_proc_single_open_devhdr,
2581         .release = single_release,
2582 };
2583
2584 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2585 static int sg_proc_open_dev(struct inode *inode, struct file *file);
2586 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2587 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2588 static void dev_seq_stop(struct seq_file *s, void *v);
2589 static struct file_operations dev_fops = {
2590         .open = sg_proc_open_dev,
2591         .release = seq_release,
2592 };
2593 static struct seq_operations dev_seq_ops = {
2594         .start = dev_seq_start,
2595         .next  = dev_seq_next,
2596         .stop  = dev_seq_stop,
2597         .show  = sg_proc_seq_show_dev,
2598 };
2599
2600 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2601 static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2602 static struct file_operations devstrs_fops = {
2603         .open = sg_proc_open_devstrs,
2604         .release = seq_release,
2605 };
2606 static struct seq_operations devstrs_seq_ops = {
2607         .start = dev_seq_start,
2608         .next  = dev_seq_next,
2609         .stop  = dev_seq_stop,
2610         .show  = sg_proc_seq_show_devstrs,
2611 };
2612
2613 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2614 static int sg_proc_open_debug(struct inode *inode, struct file *file);
2615 static struct file_operations debug_fops = {
2616         .open = sg_proc_open_debug,
2617         .release = seq_release,
2618 };
2619 static struct seq_operations debug_seq_ops = {
2620         .start = dev_seq_start,
2621         .next  = dev_seq_next,
2622         .stop  = dev_seq_stop,
2623         .show  = sg_proc_seq_show_debug,
2624 };
2625
2626
2627 struct sg_proc_leaf {
2628         const char * name;
2629         struct file_operations * fops;
2630 };
2631
2632 static struct sg_proc_leaf sg_proc_leaf_arr[] = {
2633         {"allow_dio", &adio_fops},
2634         {"debug", &debug_fops},
2635         {"def_reserved_size", &dressz_fops},
2636         {"device_hdr", &devhdr_fops},
2637         {"devices", &dev_fops},
2638         {"device_strs", &devstrs_fops},
2639         {"version", &version_fops}
2640 };
2641
2642 static int
2643 sg_proc_init(void)
2644 {
2645         int k, mask;
2646         int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2647         struct sg_proc_leaf * leaf;
2648
2649         sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2650         if (!sg_proc_sgp)
2651                 return 1;
2652         for (k = 0; k < num_leaves; ++k) {
2653                 leaf = &sg_proc_leaf_arr[k];
2654                 mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2655                 leaf->fops->owner = THIS_MODULE;
2656                 leaf->fops->read = seq_read;
2657                 leaf->fops->llseek = seq_lseek;
2658                 proc_create(leaf->name, mask, sg_proc_sgp, leaf->fops);
2659         }
2660         return 0;
2661 }
2662
2663 static void
2664 sg_proc_cleanup(void)
2665 {
2666         int k;
2667         int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2668
2669         if (!sg_proc_sgp)
2670                 return;
2671         for (k = 0; k < num_leaves; ++k)
2672                 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2673         remove_proc_entry(sg_proc_sg_dirname, NULL);
2674 }
2675
2676
2677 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2678 {
2679         seq_printf(s, "%d\n", *((int *)s->private));
2680         return 0;
2681 }
2682
2683 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2684 {
2685         return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2686 }
2687
2688 static ssize_t
2689 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2690                    size_t count, loff_t *off)
2691 {
2692         int num;
2693         char buff[11];
2694
2695         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2696                 return -EACCES;
2697         num = (count < 10) ? count : 10;
2698         if (copy_from_user(buff, buffer, num))
2699                 return -EFAULT;
2700         buff[num] = '\0';
2701         sg_allow_dio = simple_strtoul(buff, NULL, 10) ? 1 : 0;
2702         return count;
2703 }
2704
2705 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2706 {
2707         return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2708 }
2709
2710 static ssize_t
2711 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2712                      size_t count, loff_t *off)
2713 {
2714         int num;
2715         unsigned long k = ULONG_MAX;
2716         char buff[11];
2717
2718         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2719                 return -EACCES;
2720         num = (count < 10) ? count : 10;
2721         if (copy_from_user(buff, buffer, num))
2722                 return -EFAULT;
2723         buff[num] = '\0';
2724         k = simple_strtoul(buff, NULL, 10);
2725         if (k <= 1048576) {     /* limit "big buff" to 1 MB */
2726                 sg_big_buff = k;
2727                 return count;
2728         }
2729         return -ERANGE;
2730 }
2731
2732 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2733 {
2734         seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2735                    sg_version_date);
2736         return 0;
2737 }
2738
2739 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2740 {
2741         return single_open(file, sg_proc_seq_show_version, NULL);
2742 }
2743
2744 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2745 {
2746         seq_printf(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\t"
2747                    "online\n");
2748         return 0;
2749 }
2750
2751 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2752 {
2753         return single_open(file, sg_proc_seq_show_devhdr, NULL);
2754 }
2755
2756 struct sg_proc_deviter {
2757         loff_t  index;
2758         size_t  max;
2759 };
2760
2761 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2762 {
2763         struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2764
2765         s->private = it;
2766         if (! it)
2767                 return NULL;
2768
2769         it->index = *pos;
2770         it->max = sg_last_dev();
2771         if (it->index >= it->max)
2772                 return NULL;
2773         return it;
2774 }
2775
2776 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2777 {
2778         struct sg_proc_deviter * it = s->private;
2779
2780         *pos = ++it->index;
2781         return (it->index < it->max) ? it : NULL;
2782 }
2783
2784 static void dev_seq_stop(struct seq_file *s, void *v)
2785 {
2786         kfree(s->private);
2787 }
2788
2789 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2790 {
2791         return seq_open(file, &dev_seq_ops);
2792 }
2793
2794 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2795 {
2796         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2797         Sg_device *sdp;
2798         struct scsi_device *scsidp;
2799
2800         sdp = it ? sg_get_dev(it->index) : NULL;
2801         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2802                 seq_printf(s, "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n",
2803                               scsidp->host->host_no, scsidp->channel,
2804                               scsidp->id, scsidp->lun, (int) scsidp->type,
2805                               1,
2806                               (int) scsidp->queue_depth,
2807                               (int) scsidp->device_busy,
2808                               (int) scsi_device_online(scsidp));
2809         else
2810                 seq_printf(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2811         return 0;
2812 }
2813
2814 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2815 {
2816         return seq_open(file, &devstrs_seq_ops);
2817 }
2818
2819 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2820 {
2821         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2822         Sg_device *sdp;
2823         struct scsi_device *scsidp;
2824
2825         sdp = it ? sg_get_dev(it->index) : NULL;
2826         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2827                 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2828                            scsidp->vendor, scsidp->model, scsidp->rev);
2829         else
2830                 seq_printf(s, "<no active device>\n");
2831         return 0;
2832 }
2833
2834 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2835 {
2836         int k, m, new_interface, blen, usg;
2837         Sg_request *srp;
2838         Sg_fd *fp;
2839         const sg_io_hdr_t *hp;
2840         const char * cp;
2841         unsigned int ms;
2842
2843         for (k = 0; (fp = sg_get_nth_sfp(sdp, k)); ++k) {
2844                 seq_printf(s, "   FD(%d): timeout=%dms bufflen=%d "
2845                            "(res)sgat=%d low_dma=%d\n", k + 1,
2846                            jiffies_to_msecs(fp->timeout),
2847                            fp->reserve.bufflen,
2848                            (int) fp->reserve.k_use_sg,
2849                            (int) fp->low_dma);
2850                 seq_printf(s, "   cmd_q=%d f_packid=%d k_orphan=%d closed=%d\n",
2851                            (int) fp->cmd_q, (int) fp->force_packid,
2852                            (int) fp->keep_orphan, (int) fp->closed);
2853                 for (m = 0; (srp = sg_get_nth_request(fp, m)); ++m) {
2854                         hp = &srp->header;
2855                         new_interface = (hp->interface_id == '\0') ? 0 : 1;
2856                         if (srp->res_used) {
2857                                 if (new_interface &&
2858                                     (SG_FLAG_MMAP_IO & hp->flags))
2859                                         cp = "     mmap>> ";
2860                                 else
2861                                         cp = "     rb>> ";
2862                         } else {
2863                                 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2864                                         cp = "     dio>> ";
2865                                 else
2866                                         cp = "     ";
2867                         }
2868                         seq_printf(s, cp);
2869                         blen = srp->data.bufflen;
2870                         usg = srp->data.k_use_sg;
2871                         seq_printf(s, srp->done ?
2872                                    ((1 == srp->done) ?  "rcv:" : "fin:")
2873                                    : "act:");
2874                         seq_printf(s, " id=%d blen=%d",
2875                                    srp->header.pack_id, blen);
2876                         if (srp->done)
2877                                 seq_printf(s, " dur=%d", hp->duration);
2878                         else {
2879                                 ms = jiffies_to_msecs(jiffies);
2880                                 seq_printf(s, " t_o/elap=%d/%d",
2881                                         (new_interface ? hp->timeout :
2882                                                   jiffies_to_msecs(fp->timeout)),
2883                                         (ms > hp->duration ? ms - hp->duration : 0));
2884                         }
2885                         seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2886                                    (int) srp->data.cmd_opcode);
2887                 }
2888                 if (0 == m)
2889                         seq_printf(s, "     No requests active\n");
2890         }
2891 }
2892
2893 static int sg_proc_open_debug(struct inode *inode, struct file *file)
2894 {
2895         return seq_open(file, &debug_seq_ops);
2896 }
2897
2898 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2899 {
2900         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2901         Sg_device *sdp;
2902
2903         if (it && (0 == it->index)) {
2904                 seq_printf(s, "max_active_device=%d(origin 1)\n",
2905                            (int)it->max);
2906                 seq_printf(s, " def_reserved_size=%d\n", sg_big_buff);
2907         }
2908         sdp = it ? sg_get_dev(it->index) : NULL;
2909         if (sdp) {
2910                 struct scsi_device *scsidp = sdp->device;
2911
2912                 if (NULL == scsidp) {
2913                         seq_printf(s, "device %d detached ??\n",
2914                                    (int)it->index);
2915                         return 0;
2916                 }
2917
2918                 if (sg_get_nth_sfp(sdp, 0)) {
2919                         seq_printf(s, " >>> device=%s ",
2920                                 sdp->disk->disk_name);
2921                         if (sdp->detached)
2922                                 seq_printf(s, "detached pending close ");
2923                         else
2924                                 seq_printf
2925                                     (s, "scsi%d chan=%d id=%d lun=%d   em=%d",
2926                                      scsidp->host->host_no,
2927                                      scsidp->channel, scsidp->id,
2928                                      scsidp->lun,
2929                                      scsidp->host->hostt->emulated);
2930                         seq_printf(s, " sg_tablesize=%d excl=%d\n",
2931                                    sdp->sg_tablesize, sdp->exclude);
2932                 }
2933                 sg_proc_debug_helper(s, sdp);
2934         }
2935         return 0;
2936 }
2937
2938 #endif                          /* CONFIG_SCSI_PROC_FS */
2939
2940 module_init(init_sg);
2941 module_exit(exit_sg);