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

   1 /*
   2  *  History:
   3  *  Started: Aug 9 by Lawrence Foard (entropy@world.std.com),
   4  *           to allow user process control of SCSI devices.
   5  *  Development Sponsored by Killy Corp. NY NY
   6  *
   7  * Original driver (sg.c):
   8  *        Copyright (C) 1992 Lawrence Foard
   9  * Version 2 and 3 extensions to driver:
  10  *        Copyright (C) 1998 - 2005 Douglas Gilbert
  11  *
  12  *  Modified  19-JAN-1998  Richard Gooch <rgooch@atnf.csiro.au>  Devfs support
  13  *
  14  * This program is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2, or (at your option)
  17  * any later version.
  18  *
  19  */
  20
  21 static int sg_version_num = 30533;      /* 2 digits for each component */
  22 #define SG_VERSION_STR "3.5.33"
  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/config.h>
  32 #include <linux/module.h>
  33
  34 #include <linux/fs.h>
  35 #include <linux/kernel.h>
  36 #include <linux/sched.h>
  37 #include <linux/string.h>
  38 #include <linux/mm.h>
  39 #include <linux/errno.h>
  40 #include <linux/mtio.h>
  41 #include <linux/ioctl.h>
  42 #include <linux/fcntl.h>
  43 #include <linux/init.h>
  44 #include <linux/poll.h>
  45 #include <linux/smp_lock.h>
  46 #include <linux/moduleparam.h>
  47 #include <linux/cdev.h>
  48 #include <linux/seq_file.h>
  49 #include <linux/blkdev.h>
  50 #include <linux/delay.h>
  51 #include <linux/scatterlist.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 = "20050908";
  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 #define SG_SECTOR_SZ 512
  99 #define SG_SECTOR_MSK (SG_SECTOR_SZ - 1)
 100
 101 #define SG_DEV_ARR_LUMP 32      /* amount to over allocate sg_dev_arr by */
 102
 103 static int sg_add(struct class_device *, struct class_interface *);
 104 static void sg_remove(struct class_device *, struct class_interface *);
 105
 106 static DEFINE_RWLOCK(sg_dev_arr_lock);  /* Also used to lock
 107                                                            file descriptor list for device */
 108
 109 static struct class_interface sg_interface = {
 110         .add            = sg_add,
 111         .remove         = sg_remove,
 112 };
 113
 114 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
 115         unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
 116         unsigned short sglist_len; /* size of malloc'd scatter-gather list ++ */
 117         unsigned bufflen;       /* Size of (aggregate) data buffer */
 118         unsigned b_malloc_len;  /* actual len malloc'ed in buffer */
 119         struct scatterlist *buffer;/* scatter list */
 120         char dio_in_use;        /* 0->indirect IO (or mmap), 1->dio */
 121         unsigned char cmd_opcode; /* first byte of command */
 122 } Sg_scatter_hold;
 123
 124 struct sg_device;               /* forward declarations */
 125 struct sg_fd;
 126
 127 typedef struct sg_request {     /* SG_MAX_QUEUE requests outstanding per file */
 128         struct sg_request *nextrp;      /* NULL -> tail request (slist) */
 129         struct sg_fd *parentfp; /* NULL -> not in use */
 130         Sg_scatter_hold data;   /* hold buffer, perhaps scatter list */
 131         sg_io_hdr_t header;     /* scsi command+info, see <scsi/sg.h> */
 132         unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
 133         char res_used;          /* 1 -> using reserve buffer, 0 -> not ... */
 134         char orphan;            /* 1 -> drop on sight, 0 -> normal */
 135         char sg_io_owned;       /* 1 -> packet belongs to SG_IO */
 136         volatile char done;     /* 0->before bh, 1->before read, 2->read */
 137 } Sg_request;
 138
 139 typedef struct sg_fd {          /* holds the state of a file descriptor */
 140         struct sg_fd *nextfp;   /* NULL when last opened fd on this device */
 141         struct sg_device *parentdp;     /* owning device */
 142         wait_queue_head_t read_wait;    /* queue read until command done */
 143         rwlock_t rq_list_lock;  /* protect access to list in req_arr */
 144         int timeout;            /* defaults to SG_DEFAULT_TIMEOUT      */
 145         int timeout_user;       /* defaults to SG_DEFAULT_TIMEOUT_USER */
 146         Sg_scatter_hold reserve;        /* buffer held for this file descriptor */
 147         unsigned save_scat_len; /* original length of trunc. scat. element */
 148         Sg_request *headrp;     /* head of request slist, NULL->empty */
 149         struct fasync_struct *async_qp; /* used by asynchronous notification */
 150         Sg_request req_arr[SG_MAX_QUEUE];       /* used as singly-linked list */
 151         char low_dma;           /* as in parent but possibly overridden to 1 */
 152         char force_packid;      /* 1 -> pack_id input to read(), 0 -> ignored */
 153         volatile char closed;   /* 1 -> fd closed but request(s) outstanding */
 154         char cmd_q;             /* 1 -> allow command queuing, 0 -> don't */
 155         char next_cmd_len;      /* 0 -> automatic (def), >0 -> use on next write() */
 156         char keep_orphan;       /* 0 -> drop orphan (def), 1 -> keep for read() */
 157         char mmap_called;       /* 0 -> mmap() never called on this fd */
 158 } Sg_fd;
 159
 160 typedef struct sg_device { /* holds the state of each scsi generic device */
 161         struct scsi_device *device;
 162         wait_queue_head_t o_excl_wait;  /* queue open() when O_EXCL in use */
 163         int sg_tablesize;       /* adapter's max scatter-gather table size */
 164         Sg_fd *headfp;          /* first open fd belonging to this device */
 165         volatile char detached; /* 0->attached, 1->detached pending removal */
 166         volatile char exclude;  /* opened for exclusive access */
 167         char sgdebug;           /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
 168         struct gendisk *disk;
 169         struct cdev * cdev;     /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
 170 } Sg_device;
 171
 172 static int sg_fasync(int fd, struct file *filp, int mode);
 173 /* tasklet or soft irq callback */
 174 static void sg_cmd_done(void *data, char *sense, int result, int resid);
 175 static int sg_start_req(Sg_request * srp);
 176 static void sg_finish_rem_req(Sg_request * srp);
 177 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
 178 static int sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp,
 179                          int tablesize);
 180 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
 181                            Sg_request * srp);
 182 static ssize_t sg_new_write(Sg_fd * sfp, const char __user *buf, size_t count,
 183                             int blocking, int read_only, Sg_request ** o_srp);
 184 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
 185                            unsigned char *cmnd, int timeout, int blocking);
 186 static int sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
 187                       int wr_xf, int *countp, unsigned char __user **up);
 188 static int sg_write_xfer(Sg_request * srp);
 189 static int sg_read_xfer(Sg_request * srp);
 190 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
 191 static void sg_remove_scat(Sg_scatter_hold * schp);
 192 static void sg_build_reserve(Sg_fd * sfp, int req_size);
 193 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
 194 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
 195 static struct page *sg_page_malloc(int rqSz, int lowDma, int *retSzp);
 196 static void sg_page_free(struct page *page, int size);
 197 static Sg_fd *sg_add_sfp(Sg_device * sdp, int dev);
 198 static int sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
 199 static void __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
 200 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
 201 static Sg_request *sg_add_request(Sg_fd * sfp);
 202 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
 203 static int sg_res_in_use(Sg_fd * sfp);
 204 static int sg_allow_access(unsigned char opcode, char dev_type);
 205 static int sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len);
 206 static Sg_device *sg_get_dev(int dev);
 207 #ifdef CONFIG_SCSI_PROC_FS
 208 static int sg_last_dev(void);
 209 #endif
 210
 211 static Sg_device **sg_dev_arr = NULL;
 212 static int sg_dev_max;
 213 static int sg_nr_dev;
 214
 215 #define SZ_SG_HEADER sizeof(struct sg_header)
 216 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
 217 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
 218 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
 219
 220 static int
 221 sg_open(struct inode *inode, struct file *filp)
 222 {
 223         int dev = iminor(inode);
 224         int flags = filp->f_flags;
 225         struct request_queue *q;
 226         Sg_device *sdp;
 227         Sg_fd *sfp;
 228         int res;
 229         int retval;
 230
 231         nonseekable_open(inode, filp);
 232         SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags));
 233         sdp = sg_get_dev(dev);
 234         if ((!sdp) || (!sdp->device))
 235                 return -ENXIO;
 236         if (sdp->detached)
 237                 return -ENODEV;
 238
 239         /* This driver's module count bumped by fops_get in <linux/fs.h> */
 240         /* Prevent the device driver from vanishing while we sleep */
 241         retval = scsi_device_get(sdp->device);
 242         if (retval)
 243                 return retval;
 244
 245         if (!((flags & O_NONBLOCK) ||
 246               scsi_block_when_processing_errors(sdp->device))) {
 247                 retval = -ENXIO;
 248                 /* we are in error recovery for this device */
 249                 goto error_out;
 250         }
 251
 252         if (flags & O_EXCL) {
 253                 if (O_RDONLY == (flags & O_ACCMODE)) {
 254                         retval = -EPERM; /* Can't lock it with read only access */
 255                         goto error_out;
 256                 }
 257                 if (sdp->headfp && (flags & O_NONBLOCK)) {
 258                         retval = -EBUSY;
 259                         goto error_out;
 260                 }
 261                 res = 0;
 262                 __wait_event_interruptible(sdp->o_excl_wait,
 263                         ((sdp->headfp || sdp->exclude) ? 0 : (sdp->exclude = 1)), res);
 264                 if (res) {
 265                         retval = res;   /* -ERESTARTSYS because signal hit process */
 266                         goto error_out;
 267                 }
 268         } else if (sdp->exclude) {      /* some other fd has an exclusive lock on dev */
 269                 if (flags & O_NONBLOCK) {
 270                         retval = -EBUSY;
 271                         goto error_out;
 272                 }
 273                 res = 0;
 274                 __wait_event_interruptible(sdp->o_excl_wait, (!sdp->exclude),
 275                                            res);
 276                 if (res) {
 277                         retval = res;   /* -ERESTARTSYS because signal hit process */
 278                         goto error_out;
 279                 }
 280         }
 281         if (sdp->detached) {
 282                 retval = -ENODEV;
 283                 goto error_out;
 284         }
 285         if (!sdp->headfp) {     /* no existing opens on this device */
 286                 sdp->sgdebug = 0;
 287                 q = sdp->device->request_queue;
 288                 sdp->sg_tablesize = min(q->max_hw_segments,
 289                                         q->max_phys_segments);
 290         }
 291         if ((sfp = sg_add_sfp(sdp, dev)))
 292                 filp->private_data = sfp;
 293         else {
 294                 if (flags & O_EXCL)
 295                         sdp->exclude = 0;       /* undo if error */
 296                 retval = -ENOMEM;
 297                 goto error_out;
 298         }
 299         return 0;
 300
 301       error_out:
 302         scsi_device_put(sdp->device);
 303         return retval;
 304 }
 305
 306 /* Following function was formerly called 'sg_close' */
 307 static int
 308 sg_release(struct inode *inode, struct file *filp)
 309 {
 310         Sg_device *sdp;
 311         Sg_fd *sfp;
 312
 313         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 314                 return -ENXIO;
 315         SCSI_LOG_TIMEOUT(3, printk("sg_release: %s\n", sdp->disk->disk_name));
 316         sg_fasync(-1, filp, 0); /* remove filp from async notification list */
 317         if (0 == sg_remove_sfp(sdp, sfp)) {     /* Returns 1 when sdp gone */
 318                 if (!sdp->detached) {
 319                         scsi_device_put(sdp->device);
 320                 }
 321                 sdp->exclude = 0;
 322                 wake_up_interruptible(&sdp->o_excl_wait);
 323         }
 324         return 0;
 325 }
 326
 327 static ssize_t
 328 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
 329 {
 330         Sg_device *sdp;
 331         Sg_fd *sfp;
 332         Sg_request *srp;
 333         int req_pack_id = -1;
 334         sg_io_hdr_t *hp;
 335         struct sg_header *old_hdr = NULL;
 336         int retval = 0;
 337
 338         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 339                 return -ENXIO;
 340         SCSI_LOG_TIMEOUT(3, printk("sg_read: %s, count=%d\n",
 341                                    sdp->disk->disk_name, (int) count));
 342
 343         if (!access_ok(VERIFY_WRITE, buf, count))
 344                 return -EFAULT;
 345         if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
 346                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 347                 if (!old_hdr)
 348                         return -ENOMEM;
 349                 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
 350                         retval = -EFAULT;
 351                         goto free_old_hdr;
 352                 }
 353                 if (old_hdr->reply_len < 0) {
 354                         if (count >= SZ_SG_IO_HDR) {
 355                                 sg_io_hdr_t *new_hdr;
 356                                 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
 357                                 if (!new_hdr) {
 358                                         retval = -ENOMEM;
 359                                         goto free_old_hdr;
 360                                 }
 361                                 retval =__copy_from_user
 362                                     (new_hdr, buf, SZ_SG_IO_HDR);
 363                                 req_pack_id = new_hdr->pack_id;
 364                                 kfree(new_hdr);
 365                                 if (retval) {
 366                                         retval = -EFAULT;
 367                                         goto free_old_hdr;
 368                                 }
 369                         }
 370                 } else
 371                         req_pack_id = old_hdr->pack_id;
 372         }
 373         srp = sg_get_rq_mark(sfp, req_pack_id);
 374         if (!srp) {             /* now wait on packet to arrive */
 375                 if (sdp->detached) {
 376                         retval = -ENODEV;
 377                         goto free_old_hdr;
 378                 }
 379                 if (filp->f_flags & O_NONBLOCK) {
 380                         retval = -EAGAIN;
 381                         goto free_old_hdr;
 382                 }
 383                 while (1) {
 384                         retval = 0; /* following macro beats race condition */
 385                         __wait_event_interruptible(sfp->read_wait,
 386                                 (sdp->detached ||
 387                                 (srp = sg_get_rq_mark(sfp, req_pack_id))),
 388                                 retval);
 389                         if (sdp->detached) {
 390                                 retval = -ENODEV;
 391                                 goto free_old_hdr;
 392                         }
 393                         if (0 == retval)
 394                                 break;
 395
 396                         /* -ERESTARTSYS as signal hit process */
 397                         goto free_old_hdr;
 398                 }
 399         }
 400         if (srp->header.interface_id != '\0') {
 401                 retval = sg_new_read(sfp, buf, count, srp);
 402                 goto free_old_hdr;
 403         }
 404
 405         hp = &srp->header;
 406         if (old_hdr == NULL) {
 407                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 408                 if (! old_hdr) {
 409                         retval = -ENOMEM;
 410                         goto free_old_hdr;
 411                 }
 412         }
 413         memset(old_hdr, 0, SZ_SG_HEADER);
 414         old_hdr->reply_len = (int) hp->timeout;
 415         old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
 416         old_hdr->pack_id = hp->pack_id;
 417         old_hdr->twelve_byte =
 418             ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
 419         old_hdr->target_status = hp->masked_status;
 420         old_hdr->host_status = hp->host_status;
 421         old_hdr->driver_status = hp->driver_status;
 422         if ((CHECK_CONDITION & hp->masked_status) ||
 423             (DRIVER_SENSE & hp->driver_status))
 424                 memcpy(old_hdr->sense_buffer, srp->sense_b,
 425                        sizeof (old_hdr->sense_buffer));
 426         switch (hp->host_status) {
 427         /* This setup of 'result' is for backward compatibility and is best
 428            ignored by the user who should use target, host + driver status */
 429         case DID_OK:
 430         case DID_PASSTHROUGH:
 431         case DID_SOFT_ERROR:
 432                 old_hdr->result = 0;
 433                 break;
 434         case DID_NO_CONNECT:
 435         case DID_BUS_BUSY:
 436         case DID_TIME_OUT:
 437                 old_hdr->result = EBUSY;
 438                 break;
 439         case DID_BAD_TARGET:
 440         case DID_ABORT:
 441         case DID_PARITY:
 442         case DID_RESET:
 443         case DID_BAD_INTR:
 444                 old_hdr->result = EIO;
 445                 break;
 446         case DID_ERROR:
 447                 old_hdr->result = (srp->sense_b[0] == 0 &&
 448                                   hp->masked_status == GOOD) ? 0 : EIO;
 449                 break;
 450         default:
 451                 old_hdr->result = EIO;
 452                 break;
 453         }
 454
 455         /* Now copy the result back to the user buffer.  */
 456         if (count >= SZ_SG_HEADER) {
 457                 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
 458                         retval = -EFAULT;
 459                         goto free_old_hdr;
 460                 }
 461                 buf += SZ_SG_HEADER;
 462                 if (count > old_hdr->reply_len)
 463                         count = old_hdr->reply_len;
 464                 if (count > SZ_SG_HEADER) {
 465                         if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
 466                                 retval = -EFAULT;
 467                                 goto free_old_hdr;
 468                         }
 469                 }
 470         } else
 471                 count = (old_hdr->result == 0) ? 0 : -EIO;
 472         sg_finish_rem_req(srp);
 473         retval = count;
 474 free_old_hdr:
 475         kfree(old_hdr);
 476         return retval;
 477 }
 478
 479 static ssize_t
 480 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
 481 {
 482         sg_io_hdr_t *hp = &srp->header;
 483         int err = 0;
 484         int len;
 485
 486         if (count < SZ_SG_IO_HDR) {
 487                 err = -EINVAL;
 488                 goto err_out;
 489         }
 490         hp->sb_len_wr = 0;
 491         if ((hp->mx_sb_len > 0) && hp->sbp) {
 492                 if ((CHECK_CONDITION & hp->masked_status) ||
 493                     (DRIVER_SENSE & hp->driver_status)) {
 494                         int sb_len = SCSI_SENSE_BUFFERSIZE;
 495                         sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
 496                         len = 8 + (int) srp->sense_b[7];        /* Additional sense length field */
 497                         len = (len > sb_len) ? sb_len : len;
 498                         if (copy_to_user(hp->sbp, srp->sense_b, len)) {
 499                                 err = -EFAULT;
 500                                 goto err_out;
 501                         }
 502                         hp->sb_len_wr = len;
 503                 }
 504         }
 505         if (hp->masked_status || hp->host_status || hp->driver_status)
 506                 hp->info |= SG_INFO_CHECK;
 507         if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
 508                 err = -EFAULT;
 509                 goto err_out;
 510         }
 511         err = sg_read_xfer(srp);
 512       err_out:
 513         sg_finish_rem_req(srp);
 514         return (0 == err) ? count : err;
 515 }
 516
 517 static ssize_t
 518 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
 519 {
 520         int mxsize, cmd_size, k;
 521         int input_size, blocking;
 522         unsigned char opcode;
 523         Sg_device *sdp;
 524         Sg_fd *sfp;
 525         Sg_request *srp;
 526         struct sg_header old_hdr;
 527         sg_io_hdr_t *hp;
 528         unsigned char cmnd[MAX_COMMAND_SIZE];
 529
 530         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 531                 return -ENXIO;
 532         SCSI_LOG_TIMEOUT(3, printk("sg_write: %s, count=%d\n",
 533                                    sdp->disk->disk_name, (int) count));
 534         if (sdp->detached)
 535                 return -ENODEV;
 536         if (!((filp->f_flags & O_NONBLOCK) ||
 537               scsi_block_when_processing_errors(sdp->device)))
 538                 return -ENXIO;
 539
 540         if (!access_ok(VERIFY_READ, buf, count))
 541                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 542         if (count < SZ_SG_HEADER)
 543                 return -EIO;
 544         if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
 545                 return -EFAULT;
 546         blocking = !(filp->f_flags & O_NONBLOCK);
 547         if (old_hdr.reply_len < 0)
 548                 return sg_new_write(sfp, buf, count, blocking, 0, NULL);
 549         if (count < (SZ_SG_HEADER + 6))
 550                 return -EIO;    /* The minimum scsi command length is 6 bytes. */
 551
 552         if (!(srp = sg_add_request(sfp))) {
 553                 SCSI_LOG_TIMEOUT(1, printk("sg_write: queue full\n"));
 554                 return -EDOM;
 555         }
 556         buf += SZ_SG_HEADER;
 557         __get_user(opcode, buf);
 558         if (sfp->next_cmd_len > 0) {
 559                 if (sfp->next_cmd_len > MAX_COMMAND_SIZE) {
 560                         SCSI_LOG_TIMEOUT(1, printk("sg_write: command length too long\n"));
 561                         sfp->next_cmd_len = 0;
 562                         sg_remove_request(sfp, srp);
 563                         return -EIO;
 564                 }
 565                 cmd_size = sfp->next_cmd_len;
 566                 sfp->next_cmd_len = 0;  /* reset so only this write() effected */
 567         } else {
 568                 cmd_size = COMMAND_SIZE(opcode);        /* based on SCSI command group */
 569                 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
 570                         cmd_size = 12;
 571         }
 572         SCSI_LOG_TIMEOUT(4, printk(
 573                 "sg_write:   scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
 574 /* Determine buffer size.  */
 575         input_size = count - cmd_size;
 576         mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
 577         mxsize -= SZ_SG_HEADER;
 578         input_size -= SZ_SG_HEADER;
 579         if (input_size < 0) {
 580                 sg_remove_request(sfp, srp);
 581                 return -EIO;    /* User did not pass enough bytes for this command. */
 582         }
 583         hp = &srp->header;
 584         hp->interface_id = '\0';        /* indicator of old interface tunnelled */
 585         hp->cmd_len = (unsigned char) cmd_size;
 586         hp->iovec_count = 0;
 587         hp->mx_sb_len = 0;
 588         if (input_size > 0)
 589                 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
 590                     SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
 591         else
 592                 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
 593         hp->dxfer_len = mxsize;
 594         hp->dxferp = (char __user *)buf + cmd_size;
 595         hp->sbp = NULL;
 596         hp->timeout = old_hdr.reply_len;        /* structure abuse ... */
 597         hp->flags = input_size; /* structure abuse ... */
 598         hp->pack_id = old_hdr.pack_id;
 599         hp->usr_ptr = NULL;
 600         if (__copy_from_user(cmnd, buf, cmd_size))
 601                 return -EFAULT;
 602         /*
 603          * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
 604          * but is is possible that the app intended SG_DXFER_TO_DEV, because there
 605          * is a non-zero input_size, so emit a warning.
 606          */
 607         if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV)
 608                 if (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         k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
 617         return (k < 0) ? k : count;
 618 }
 619
 620 static ssize_t
 621 sg_new_write(Sg_fd * sfp, const char __user *buf, size_t count,
 622              int blocking, int read_only, Sg_request ** o_srp)
 623 {
 624         int k;
 625         Sg_request *srp;
 626         sg_io_hdr_t *hp;
 627         unsigned char cmnd[MAX_COMMAND_SIZE];
 628         int timeout;
 629         unsigned long ul_timeout;
 630
 631         if (count < SZ_SG_IO_HDR)
 632                 return -EINVAL;
 633         if (!access_ok(VERIFY_READ, buf, count))
 634                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 635
 636         sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
 637         if (!(srp = sg_add_request(sfp))) {
 638                 SCSI_LOG_TIMEOUT(1, printk("sg_new_write: queue full\n"));
 639                 return -EDOM;
 640         }
 641         hp = &srp->header;
 642         if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
 643                 sg_remove_request(sfp, srp);
 644                 return -EFAULT;
 645         }
 646         if (hp->interface_id != 'S') {
 647                 sg_remove_request(sfp, srp);
 648                 return -ENOSYS;
 649         }
 650         if (hp->flags & SG_FLAG_MMAP_IO) {
 651                 if (hp->dxfer_len > sfp->reserve.bufflen) {
 652                         sg_remove_request(sfp, srp);
 653                         return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
 654                 }
 655                 if (hp->flags & SG_FLAG_DIRECT_IO) {
 656                         sg_remove_request(sfp, srp);
 657                         return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
 658                 }
 659                 if (sg_res_in_use(sfp)) {
 660                         sg_remove_request(sfp, srp);
 661                         return -EBUSY;  /* reserve buffer already being used */
 662                 }
 663         }
 664         ul_timeout = msecs_to_jiffies(srp->header.timeout);
 665         timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
 666         if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
 667                 sg_remove_request(sfp, srp);
 668                 return -EMSGSIZE;
 669         }
 670         if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
 671                 sg_remove_request(sfp, srp);
 672                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 673         }
 674         if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
 675                 sg_remove_request(sfp, srp);
 676                 return -EFAULT;
 677         }
 678         if (read_only &&
 679             (!sg_allow_access(cmnd[0], sfp->parentdp->device->type))) {
 680                 sg_remove_request(sfp, srp);
 681                 return -EPERM;
 682         }
 683         k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
 684         if (k < 0)
 685                 return k;
 686         if (o_srp)
 687                 *o_srp = srp;
 688         return count;
 689 }
 690
 691 static int
 692 sg_common_write(Sg_fd * sfp, Sg_request * srp,
 693                 unsigned char *cmnd, int timeout, int blocking)
 694 {
 695         int k, data_dir;
 696         Sg_device *sdp = sfp->parentdp;
 697         sg_io_hdr_t *hp = &srp->header;
 698
 699         srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
 700         hp->status = 0;
 701         hp->masked_status = 0;
 702         hp->msg_status = 0;
 703         hp->info = 0;
 704         hp->host_status = 0;
 705         hp->driver_status = 0;
 706         hp->resid = 0;
 707         SCSI_LOG_TIMEOUT(4, printk("sg_common_write:  scsi opcode=0x%02x, cmd_size=%d\n",
 708                           (int) cmnd[0], (int) hp->cmd_len));
 709
 710         if ((k = sg_start_req(srp))) {
 711                 SCSI_LOG_TIMEOUT(1, printk("sg_write: start_req err=%d\n", k));
 712                 sg_finish_rem_req(srp);
 713                 return k;       /* probably out of space --> ENOMEM */
 714         }
 715         if ((k = sg_write_xfer(srp))) {
 716                 SCSI_LOG_TIMEOUT(1, printk("sg_write: write_xfer, bad address\n"));
 717                 sg_finish_rem_req(srp);
 718                 return k;
 719         }
 720         if (sdp->detached) {
 721                 sg_finish_rem_req(srp);
 722                 return -ENODEV;
 723         }
 724
 725         switch (hp->dxfer_direction) {
 726         case SG_DXFER_TO_FROM_DEV:
 727         case SG_DXFER_FROM_DEV:
 728                 data_dir = DMA_FROM_DEVICE;
 729                 break;
 730         case SG_DXFER_TO_DEV:
 731                 data_dir = DMA_TO_DEVICE;
 732                 break;
 733         case SG_DXFER_UNKNOWN:
 734                 data_dir = DMA_BIDIRECTIONAL;
 735                 break;
 736         default:
 737                 data_dir = DMA_NONE;
 738                 break;
 739         }
 740         hp->duration = jiffies_to_msecs(jiffies);
 741 /* Now send everything of to mid-level. The next time we hear about this
 742    packet is when sg_cmd_done() is called (i.e. a callback). */
 743         if (scsi_execute_async(sdp->device, cmnd, hp->cmd_len, data_dir, srp->data.buffer,
 744                                 hp->dxfer_len, srp->data.k_use_sg, timeout,
 745                                 SG_DEFAULT_RETRIES, srp, sg_cmd_done,
 746                                 GFP_ATOMIC)) {
 747                 SCSI_LOG_TIMEOUT(1, printk("sg_write: scsi_execute_async failed\n"));
 748                 /*
 749                  * most likely out of mem, but could also be a bad map
 750                  */
 751                 return -ENOMEM;
 752         } else
 753                 return 0;
 754 }
 755
 756 static int
 757 sg_srp_done(Sg_request *srp, Sg_fd *sfp)
 758 {
 759         unsigned long iflags;
 760         int done;
 761
 762         read_lock_irqsave(&sfp->rq_list_lock, iflags);
 763         done = srp->done;
 764         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 765         return done;
 766 }
 767
 768 static int
 769 sg_ioctl(struct inode *inode, struct file *filp,
 770          unsigned int cmd_in, unsigned long arg)
 771 {
 772         void __user *p = (void __user *)arg;
 773         int __user *ip = p;
 774         int result, val, read_only;
 775         Sg_device *sdp;
 776         Sg_fd *sfp;
 777         Sg_request *srp;
 778         unsigned long iflags;
 779
 780         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 781                 return -ENXIO;
 782         SCSI_LOG_TIMEOUT(3, printk("sg_ioctl: %s, cmd=0x%x\n",
 783                                    sdp->disk->disk_name, (int) cmd_in));
 784         read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
 785
 786         switch (cmd_in) {
 787         case SG_IO:
 788                 {
 789                         int blocking = 1;       /* ignore O_NONBLOCK flag */
 790
 791                         if (sdp->detached)
 792                                 return -ENODEV;
 793                         if (!scsi_block_when_processing_errors(sdp->device))
 794                                 return -ENXIO;
 795                         if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
 796                                 return -EFAULT;
 797                         result =
 798                             sg_new_write(sfp, p, SZ_SG_IO_HDR,
 799                                          blocking, read_only, &srp);
 800                         if (result < 0)
 801                                 return result;
 802                         srp->sg_io_owned = 1;
 803                         while (1) {
 804                                 result = 0;     /* following macro to beat race condition */
 805                                 __wait_event_interruptible(sfp->read_wait,
 806                                         (sdp->detached || sfp->closed || sg_srp_done(srp, sfp)),
 807                                                            result);
 808                                 if (sdp->detached)
 809                                         return -ENODEV;
 810                                 if (sfp->closed)
 811                                         return 0;       /* request packet dropped already */
 812                                 if (0 == result)
 813                                         break;
 814                                 srp->orphan = 1;
 815                                 return result;  /* -ERESTARTSYS because signal hit process */
 816                         }
 817                         write_lock_irqsave(&sfp->rq_list_lock, iflags);
 818                         srp->done = 2;
 819                         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 820                         result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
 821                         return (result < 0) ? result : 0;
 822                 }
 823         case SG_SET_TIMEOUT:
 824                 result = get_user(val, ip);
 825                 if (result)
 826                         return result;
 827                 if (val < 0)
 828                         return -EIO;
 829                 if (val >= MULDIV (INT_MAX, USER_HZ, HZ))
 830                     val = MULDIV (INT_MAX, USER_HZ, HZ);
 831                 sfp->timeout_user = val;
 832                 sfp->timeout = MULDIV (val, HZ, USER_HZ);
 833
 834                 return 0;
 835         case SG_GET_TIMEOUT:    /* N.B. User receives timeout as return value */
 836                                 /* strange ..., for backward compatibility */
 837                 return sfp->timeout_user;
 838         case SG_SET_FORCE_LOW_DMA:
 839                 result = get_user(val, ip);
 840                 if (result)
 841                         return result;
 842                 if (val) {
 843                         sfp->low_dma = 1;
 844                         if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
 845                                 val = (int) sfp->reserve.bufflen;
 846                                 sg_remove_scat(&sfp->reserve);
 847                                 sg_build_reserve(sfp, val);
 848                         }
 849                 } else {
 850                         if (sdp->detached)
 851                                 return -ENODEV;
 852                         sfp->low_dma = sdp->device->host->unchecked_isa_dma;
 853                 }
 854                 return 0;
 855         case SG_GET_LOW_DMA:
 856                 return put_user((int) sfp->low_dma, ip);
 857         case SG_GET_SCSI_ID:
 858                 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
 859                         return -EFAULT;
 860                 else {
 861                         sg_scsi_id_t __user *sg_idp = p;
 862
 863                         if (sdp->detached)
 864                                 return -ENODEV;
 865                         __put_user((int) sdp->device->host->host_no,
 866                                    &sg_idp->host_no);
 867                         __put_user((int) sdp->device->channel,
 868                                    &sg_idp->channel);
 869                         __put_user((int) sdp->device->id, &sg_idp->scsi_id);
 870                         __put_user((int) sdp->device->lun, &sg_idp->lun);
 871                         __put_user((int) sdp->device->type, &sg_idp->scsi_type);
 872                         __put_user((short) sdp->device->host->cmd_per_lun,
 873                                    &sg_idp->h_cmd_per_lun);
 874                         __put_user((short) sdp->device->queue_depth,
 875                                    &sg_idp->d_queue_depth);
 876                         __put_user(0, &sg_idp->unused[0]);
 877                         __put_user(0, &sg_idp->unused[1]);
 878                         return 0;
 879                 }
 880         case SG_SET_FORCE_PACK_ID:
 881                 result = get_user(val, ip);
 882                 if (result)
 883                         return result;
 884                 sfp->force_packid = val ? 1 : 0;
 885                 return 0;
 886         case SG_GET_PACK_ID:
 887                 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
 888                         return -EFAULT;
 889                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 890                 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
 891                         if ((1 == srp->done) && (!srp->sg_io_owned)) {
 892                                 read_unlock_irqrestore(&sfp->rq_list_lock,
 893                                                        iflags);
 894                                 __put_user(srp->header.pack_id, ip);
 895                                 return 0;
 896                         }
 897                 }
 898                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 899                 __put_user(-1, ip);
 900                 return 0;
 901         case SG_GET_NUM_WAITING:
 902                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 903                 for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) {
 904                         if ((1 == srp->done) && (!srp->sg_io_owned))
 905                                 ++val;
 906                 }
 907                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 908                 return put_user(val, ip);
 909         case SG_GET_SG_TABLESIZE:
 910                 return put_user(sdp->sg_tablesize, ip);
 911         case SG_SET_RESERVED_SIZE:
 912                 result = get_user(val, ip);
 913                 if (result)
 914                         return result;
 915                 if (val < 0)
 916                         return -EINVAL;
 917                 if (val != sfp->reserve.bufflen) {
 918                         if (sg_res_in_use(sfp) || sfp->mmap_called)
 919                                 return -EBUSY;
 920                         sg_remove_scat(&sfp->reserve);
 921                         sg_build_reserve(sfp, val);
 922                 }
 923                 return 0;
 924         case SG_GET_RESERVED_SIZE:
 925                 val = (int) sfp->reserve.bufflen;
 926                 return put_user(val, ip);
 927         case SG_SET_COMMAND_Q:
 928                 result = get_user(val, ip);
 929                 if (result)
 930                         return result;
 931                 sfp->cmd_q = val ? 1 : 0;
 932                 return 0;
 933         case SG_GET_COMMAND_Q:
 934                 return put_user((int) sfp->cmd_q, ip);
 935         case SG_SET_KEEP_ORPHAN:
 936                 result = get_user(val, ip);
 937                 if (result)
 938                         return result;
 939                 sfp->keep_orphan = val;
 940                 return 0;
 941         case SG_GET_KEEP_ORPHAN:
 942                 return put_user((int) sfp->keep_orphan, ip);
 943         case SG_NEXT_CMD_LEN:
 944                 result = get_user(val, ip);
 945                 if (result)
 946                         return result;
 947                 sfp->next_cmd_len = (val > 0) ? val : 0;
 948                 return 0;
 949         case SG_GET_VERSION_NUM:
 950                 return put_user(sg_version_num, ip);
 951         case SG_GET_ACCESS_COUNT:
 952                 /* faked - we don't have a real access count anymore */
 953                 val = (sdp->device ? 1 : 0);
 954                 return put_user(val, ip);
 955         case SG_GET_REQUEST_TABLE:
 956                 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
 957                         return -EFAULT;
 958                 else {
 959                         sg_req_info_t *rinfo;
 960                         unsigned int ms;
 961
 962                         rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
 963                                                                 GFP_KERNEL);
 964                         if (!rinfo)
 965                                 return -ENOMEM;
 966                         read_lock_irqsave(&sfp->rq_list_lock, iflags);
 967                         for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE;
 968                              ++val, srp = srp ? srp->nextrp : srp) {
 969                                 memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
 970                                 if (srp) {
 971                                         rinfo[val].req_state = srp->done + 1;
 972                                         rinfo[val].problem =
 973                                             srp->header.masked_status &
 974                                             srp->header.host_status &
 975                                             srp->header.driver_status;
 976                                         if (srp->done)
 977                                                 rinfo[val].duration =
 978                                                         srp->header.duration;
 979                                         else {
 980                                                 ms = jiffies_to_msecs(jiffies);
 981                                                 rinfo[val].duration =
 982                                                     (ms > srp->header.duration) ?
 983                                                     (ms - srp->header.duration) : 0;
 984                                         }
 985                                         rinfo[val].orphan = srp->orphan;
 986                                         rinfo[val].sg_io_owned =
 987                                                         srp->sg_io_owned;
 988                                         rinfo[val].pack_id =
 989                                                         srp->header.pack_id;
 990                                         rinfo[val].usr_ptr =
 991                                                         srp->header.usr_ptr;
 992                                 }
 993                         }
 994                         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 995                         result = __copy_to_user(p, rinfo,
 996                                                 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
 997                         result = result ? -EFAULT : 0;
 998                         kfree(rinfo);
 999                         return result;
1000                 }
1001         case SG_EMULATED_HOST:
1002                 if (sdp->detached)
1003                         return -ENODEV;
1004                 return put_user(sdp->device->host->hostt->emulated, ip);
1005         case SG_SCSI_RESET:
1006                 if (sdp->detached)
1007                         return -ENODEV;
1008                 if (filp->f_flags & O_NONBLOCK) {
1009                         if (scsi_host_in_recovery(sdp->device->host))
1010                                 return -EBUSY;
1011                 } else if (!scsi_block_when_processing_errors(sdp->device))
1012                         return -EBUSY;
1013                 result = get_user(val, ip);
1014                 if (result)
1015                         return result;
1016                 if (SG_SCSI_RESET_NOTHING == val)
1017                         return 0;
1018                 switch (val) {
1019                 case SG_SCSI_RESET_DEVICE:
1020                         val = SCSI_TRY_RESET_DEVICE;
1021                         break;
1022                 case SG_SCSI_RESET_BUS:
1023                         val = SCSI_TRY_RESET_BUS;
1024                         break;
1025                 case SG_SCSI_RESET_HOST:
1026                         val = SCSI_TRY_RESET_HOST;
1027                         break;
1028                 default:
1029                         return -EINVAL;
1030                 }
1031                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1032                         return -EACCES;
1033                 return (scsi_reset_provider(sdp->device, val) ==
1034                         SUCCESS) ? 0 : -EIO;
1035         case SCSI_IOCTL_SEND_COMMAND:
1036                 if (sdp->detached)
1037                         return -ENODEV;
1038                 if (read_only) {
1039                         unsigned char opcode = WRITE_6;
1040                         Scsi_Ioctl_Command __user *siocp = p;
1041
1042                         if (copy_from_user(&opcode, siocp->data, 1))
1043                                 return -EFAULT;
1044                         if (!sg_allow_access(opcode, sdp->device->type))
1045                                 return -EPERM;
1046                 }
1047                 return scsi_ioctl_send_command(sdp->device, p);
1048         case SG_SET_DEBUG:
1049                 result = get_user(val, ip);
1050                 if (result)
1051                         return result;
1052                 sdp->sgdebug = (char) val;
1053                 return 0;
1054         case SCSI_IOCTL_GET_IDLUN:
1055         case SCSI_IOCTL_GET_BUS_NUMBER:
1056         case SCSI_IOCTL_PROBE_HOST:
1057         case SG_GET_TRANSFORM:
1058                 if (sdp->detached)
1059                         return -ENODEV;
1060                 return scsi_ioctl(sdp->device, cmd_in, p);
1061         default:
1062                 if (read_only)
1063                         return -EPERM;  /* don't know so take safe approach */
1064                 return scsi_ioctl(sdp->device, cmd_in, p);
1065         }
1066 }
1067
1068 #ifdef CONFIG_COMPAT
1069 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1070 {
1071         Sg_device *sdp;
1072         Sg_fd *sfp;
1073         struct scsi_device *sdev;
1074
1075         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1076                 return -ENXIO;
1077
1078         sdev = sdp->device;
1079         if (sdev->host->hostt->compat_ioctl) {
1080                 int ret;
1081
1082                 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1083
1084                 return ret;
1085         }
1086
1087         return -ENOIOCTLCMD;
1088 }
1089 #endif
1090
1091 static unsigned int
1092 sg_poll(struct file *filp, poll_table * wait)
1093 {
1094         unsigned int res = 0;
1095         Sg_device *sdp;
1096         Sg_fd *sfp;
1097         Sg_request *srp;
1098         int count = 0;
1099         unsigned long iflags;
1100
1101         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))
1102             || sfp->closed)
1103                 return POLLERR;
1104         poll_wait(filp, &sfp->read_wait, wait);
1105         read_lock_irqsave(&sfp->rq_list_lock, iflags);
1106         for (srp = sfp->headrp; srp; srp = srp->nextrp) {
1107                 /* if any read waiting, flag it */
1108                 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1109                         res = POLLIN | POLLRDNORM;
1110                 ++count;
1111         }
1112         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1113
1114         if (sdp->detached)
1115                 res |= POLLHUP;
1116         else if (!sfp->cmd_q) {
1117                 if (0 == count)
1118                         res |= POLLOUT | POLLWRNORM;
1119         } else if (count < SG_MAX_QUEUE)
1120                 res |= POLLOUT | POLLWRNORM;
1121         SCSI_LOG_TIMEOUT(3, printk("sg_poll: %s, res=0x%x\n",
1122                                    sdp->disk->disk_name, (int) res));
1123         return res;
1124 }
1125
1126 static int
1127 sg_fasync(int fd, struct file *filp, int mode)
1128 {
1129         int retval;
1130         Sg_device *sdp;
1131         Sg_fd *sfp;
1132
1133         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1134                 return -ENXIO;
1135         SCSI_LOG_TIMEOUT(3, printk("sg_fasync: %s, mode=%d\n",
1136                                    sdp->disk->disk_name, mode));
1137
1138         retval = fasync_helper(fd, filp, mode, &sfp->async_qp);
1139         return (retval < 0) ? retval : 0;
1140 }
1141
1142 /* When startFinish==1 increments page counts for pages other than the
1143    first of scatter gather elements obtained from alloc_pages().
1144    When startFinish==0 decrements ... */
1145 static void
1146 sg_rb_correct4mmap(Sg_scatter_hold * rsv_schp, int startFinish)
1147 {
1148         struct scatterlist *sg = rsv_schp->buffer;
1149         struct page *page;
1150         int k, m;
1151
1152         SCSI_LOG_TIMEOUT(3, printk("sg_rb_correct4mmap: startFinish=%d, scatg=%d\n",
1153                                    startFinish, rsv_schp->k_use_sg));
1154         /* N.B. correction _not_ applied to base page of each allocation */
1155         for (k = 0; k < rsv_schp->k_use_sg; ++k, ++sg) {
1156                 for (m = PAGE_SIZE; m < sg->length; m += PAGE_SIZE) {
1157                         page = sg->page;
1158                         if (startFinish)
1159                                 get_page(page);
1160                         else {
1161                                 if (page_count(page) > 0)
1162                                         __put_page(page);
1163                         }
1164                 }
1165         }
1166 }
1167
1168 static struct page *
1169 sg_vma_nopage(struct vm_area_struct *vma, unsigned long addr, int *type)
1170 {
1171         Sg_fd *sfp;
1172         struct page *page = NOPAGE_SIGBUS;
1173         unsigned long offset, len, sa;
1174         Sg_scatter_hold *rsv_schp;
1175         struct scatterlist *sg;
1176         int k;
1177
1178         if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1179                 return page;
1180         rsv_schp = &sfp->reserve;
1181         offset = addr - vma->vm_start;
1182         if (offset >= rsv_schp->bufflen)
1183                 return page;
1184         SCSI_LOG_TIMEOUT(3, printk("sg_vma_nopage: offset=%lu, scatg=%d\n",
1185                                    offset, rsv_schp->k_use_sg));
1186         sg = rsv_schp->buffer;
1187         sa = vma->vm_start;
1188         for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
1189              ++k, ++sg) {
1190                 len = vma->vm_end - sa;
1191                 len = (len < sg->length) ? len : sg->length;
1192                 if (offset < len) {
1193                         page = sg->page;
1194                         get_page(page); /* increment page count */
1195                         break;
1196                 }
1197                 sa += len;
1198                 offset -= len;
1199         }
1200
1201         if (type)
1202                 *type = VM_FAULT_MINOR;
1203         return page;
1204 }
1205
1206 static struct vm_operations_struct sg_mmap_vm_ops = {
1207         .nopage = sg_vma_nopage,
1208 };
1209
1210 static int
1211 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1212 {
1213         Sg_fd *sfp;
1214         unsigned long req_sz, len, sa;
1215         Sg_scatter_hold *rsv_schp;
1216         int k;
1217         struct scatterlist *sg;
1218
1219         if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1220                 return -ENXIO;
1221         req_sz = vma->vm_end - vma->vm_start;
1222         SCSI_LOG_TIMEOUT(3, printk("sg_mmap starting, vm_start=%p, len=%d\n",
1223                                    (void *) vma->vm_start, (int) req_sz));
1224         if (vma->vm_pgoff)
1225                 return -EINVAL; /* want no offset */
1226         rsv_schp = &sfp->reserve;
1227         if (req_sz > rsv_schp->bufflen)
1228                 return -ENOMEM; /* cannot map more than reserved buffer */
1229
1230         sa = vma->vm_start;
1231         sg = rsv_schp->buffer;
1232         for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
1233              ++k, ++sg) {
1234                 len = vma->vm_end - sa;
1235                 len = (len < sg->length) ? len : sg->length;
1236                 sa += len;
1237         }
1238
1239         if (0 == sfp->mmap_called) {
1240                 sg_rb_correct4mmap(rsv_schp, 1);        /* do only once per fd lifetime */
1241                 sfp->mmap_called = 1;
1242         }
1243         vma->vm_flags |= VM_RESERVED;
1244         vma->vm_private_data = sfp;
1245         vma->vm_ops = &sg_mmap_vm_ops;
1246         return 0;
1247 }
1248
1249 /* This function is a "bottom half" handler that is called by the
1250  * mid level when a command is completed (or has failed). */
1251 static void
1252 sg_cmd_done(void *data, char *sense, int result, int resid)
1253 {
1254         Sg_request *srp = data;
1255         Sg_device *sdp = NULL;
1256         Sg_fd *sfp;
1257         unsigned long iflags;
1258         unsigned int ms;
1259
1260         if (NULL == srp) {
1261                 printk(KERN_ERR "sg_cmd_done: NULL request\n");
1262                 return;
1263         }
1264         sfp = srp->parentfp;
1265         if (sfp)
1266                 sdp = sfp->parentdp;
1267         if ((NULL == sdp) || sdp->detached) {
1268                 printk(KERN_INFO "sg_cmd_done: device detached\n");
1269                 return;
1270         }
1271
1272
1273         SCSI_LOG_TIMEOUT(4, printk("sg_cmd_done: %s, pack_id=%d, res=0x%x\n",
1274                 sdp->disk->disk_name, srp->header.pack_id, result));
1275         srp->header.resid = resid;
1276         ms = jiffies_to_msecs(jiffies);
1277         srp->header.duration = (ms > srp->header.duration) ?
1278                                 (ms - srp->header.duration) : 0;
1279         if (0 != result) {
1280                 struct scsi_sense_hdr sshdr;
1281
1282                 memcpy(srp->sense_b, sense, sizeof (srp->sense_b));
1283                 srp->header.status = 0xff & result;
1284                 srp->header.masked_status = status_byte(result);
1285                 srp->header.msg_status = msg_byte(result);
1286                 srp->header.host_status = host_byte(result);
1287                 srp->header.driver_status = driver_byte(result);
1288                 if ((sdp->sgdebug > 0) &&
1289                     ((CHECK_CONDITION == srp->header.masked_status) ||
1290                      (COMMAND_TERMINATED == srp->header.masked_status)))
1291                         __scsi_print_sense("sg_cmd_done", sense,
1292                                            SCSI_SENSE_BUFFERSIZE);
1293
1294                 /* Following if statement is a patch supplied by Eric Youngdale */
1295                 if (driver_byte(result) != 0
1296                     && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1297                     && !scsi_sense_is_deferred(&sshdr)
1298                     && sshdr.sense_key == UNIT_ATTENTION
1299                     && sdp->device->removable) {
1300                         /* Detected possible disc change. Set the bit - this */
1301                         /* may be used if there are filesystems using this device */
1302                         sdp->device->changed = 1;
1303                 }
1304         }
1305         /* Rely on write phase to clean out srp status values, so no "else" */
1306
1307         if (sfp->closed) {      /* whoops this fd already released, cleanup */
1308                 SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, freeing ...\n"));
1309                 sg_finish_rem_req(srp);
1310                 srp = NULL;
1311                 if (NULL == sfp->headrp) {
1312                         SCSI_LOG_TIMEOUT(1, printk("sg...bh: already closed, final cleanup\n"));
1313                         if (0 == sg_remove_sfp(sdp, sfp)) {     /* device still present */
1314                                 scsi_device_put(sdp->device);
1315                         }
1316                         sfp = NULL;
1317                 }
1318         } else if (srp && srp->orphan) {
1319                 if (sfp->keep_orphan)
1320                         srp->sg_io_owned = 0;
1321                 else {
1322                         sg_finish_rem_req(srp);
1323                         srp = NULL;
1324                 }
1325         }
1326         if (sfp && srp) {
1327                 /* Now wake up any sg_read() that is waiting for this packet. */
1328                 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1329                 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1330                 srp->done = 1;
1331                 wake_up_interruptible(&sfp->read_wait);
1332                 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1333         }
1334 }
1335
1336 static struct file_operations sg_fops = {
1337         .owner = THIS_MODULE,
1338         .read = sg_read,
1339         .write = sg_write,
1340         .poll = sg_poll,
1341         .ioctl = sg_ioctl,
1342 #ifdef CONFIG_COMPAT
1343         .compat_ioctl = sg_compat_ioctl,
1344 #endif
1345         .open = sg_open,
1346         .mmap = sg_mmap,
1347         .release = sg_release,
1348         .fasync = sg_fasync,
1349 };
1350
1351 static struct class *sg_sysfs_class;
1352
1353 static int sg_sysfs_valid = 0;
1354
1355 static int sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1356 {
1357         struct request_queue *q = scsidp->request_queue;
1358         Sg_device *sdp;
1359         unsigned long iflags;
1360         void *old_sg_dev_arr = NULL;
1361         int k, error;
1362
1363         sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1364         if (!sdp) {
1365                 printk(KERN_WARNING "kmalloc Sg_device failure\n");
1366                 return -ENOMEM;
1367         }
1368
1369         write_lock_irqsave(&sg_dev_arr_lock, iflags);
1370         if (unlikely(sg_nr_dev >= sg_dev_max)) {        /* try to resize */
1371                 Sg_device **tmp_da;
1372                 int tmp_dev_max = sg_nr_dev + SG_DEV_ARR_LUMP;
1373                 write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1374
1375                 tmp_da = kzalloc(tmp_dev_max * sizeof(Sg_device *), GFP_KERNEL);
1376                 if (unlikely(!tmp_da))
1377                         goto expand_failed;
1378
1379                 write_lock_irqsave(&sg_dev_arr_lock, iflags);
1380                 memcpy(tmp_da, sg_dev_arr, sg_dev_max * sizeof(Sg_device *));
1381                 old_sg_dev_arr = sg_dev_arr;
1382                 sg_dev_arr = tmp_da;
1383                 sg_dev_max = tmp_dev_max;
1384         }
1385
1386         for (k = 0; k < sg_dev_max; k++)
1387                 if (!sg_dev_arr[k])
1388                         break;
1389         if (unlikely(k >= SG_MAX_DEVS))
1390                 goto overflow;
1391
1392         SCSI_LOG_TIMEOUT(3, printk("sg_alloc: dev=%d \n", k));
1393         sprintf(disk->disk_name, "sg%d", k);
1394         disk->first_minor = k;
1395         sdp->disk = disk;
1396         sdp->device = scsidp;
1397         init_waitqueue_head(&sdp->o_excl_wait);
1398         sdp->sg_tablesize = min(q->max_hw_segments, q->max_phys_segments);
1399
1400         sg_nr_dev++;
1401         sg_dev_arr[k] = sdp;
1402         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1403         error = k;
1404
1405  out:
1406         if (error < 0)
1407                 kfree(sdp);
1408         kfree(old_sg_dev_arr);
1409         return error;
1410
1411  expand_failed:
1412         printk(KERN_WARNING "sg_alloc: device array cannot be resized\n");
1413         error = -ENOMEM;
1414         goto out;
1415
1416  overflow:
1417         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1418         sdev_printk(KERN_WARNING, scsidp,
1419                     "Unable to attach sg device type=%d, minor "
1420                     "number exceeds %d\n", scsidp->type, SG_MAX_DEVS - 1);
1421         error = -ENODEV;
1422         goto out;
1423 }
1424
1425 static int
1426 sg_add(struct class_device *cl_dev, struct class_interface *cl_intf)
1427 {
1428         struct scsi_device *scsidp = to_scsi_device(cl_dev->dev);
1429         struct gendisk *disk;
1430         Sg_device *sdp = NULL;
1431         struct cdev * cdev = NULL;
1432         int error, k;
1433
1434         disk = alloc_disk(1);
1435         if (!disk) {
1436                 printk(KERN_WARNING "alloc_disk failed\n");
1437                 return -ENOMEM;
1438         }
1439         disk->major = SCSI_GENERIC_MAJOR;
1440
1441         error = -ENOMEM;
1442         cdev = cdev_alloc();
1443         if (!cdev) {
1444                 printk(KERN_WARNING "cdev_alloc failed\n");
1445                 goto out;
1446         }
1447         cdev->owner = THIS_MODULE;
1448         cdev->ops = &sg_fops;
1449
1450         error = sg_alloc(disk, scsidp);
1451         if (error < 0) {
1452                 printk(KERN_WARNING "sg_alloc failed\n");
1453                 goto out;
1454         }
1455         k = error;
1456         sdp = sg_dev_arr[k];
1457
1458         error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, k), 1);
1459         if (error)
1460                 goto out;
1461
1462         sdp->cdev = cdev;
1463         if (sg_sysfs_valid) {
1464                 struct class_device * sg_class_member;
1465
1466                 sg_class_member = class_device_create(sg_sysfs_class, NULL,
1467                                 MKDEV(SCSI_GENERIC_MAJOR, k),
1468                                 cl_dev->dev, "%s",
1469                                 disk->disk_name);
1470                 if (IS_ERR(sg_class_member))
1471                         printk(KERN_WARNING "sg_add: "
1472                                 "class_device_create failed\n");
1473                 class_set_devdata(sg_class_member, sdp);
1474                 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1475                                           &sg_class_member->kobj, "generic");
1476                 if (error)
1477                         printk(KERN_ERR "sg_add: unable to make symlink "
1478                                         "'generic' back to sg%d\n", k);
1479         } else
1480                 printk(KERN_WARNING "sg_add: sg_sys INvalid\n");
1481
1482         sdev_printk(KERN_NOTICE, scsidp,
1483                     "Attached scsi generic sg%d type %d\n", k,scsidp->type);
1484
1485         return 0;
1486
1487 out:
1488         put_disk(disk);
1489         if (cdev)
1490                 cdev_del(cdev);
1491         return error;
1492 }
1493
1494 static void
1495 sg_remove(struct class_device *cl_dev, struct class_interface *cl_intf)
1496 {
1497         struct scsi_device *scsidp = to_scsi_device(cl_dev->dev);
1498         Sg_device *sdp = NULL;
1499         unsigned long iflags;
1500         Sg_fd *sfp;
1501         Sg_fd *tsfp;
1502         Sg_request *srp;
1503         Sg_request *tsrp;
1504         int k, delay;
1505
1506         if (NULL == sg_dev_arr)
1507                 return;
1508         delay = 0;
1509         write_lock_irqsave(&sg_dev_arr_lock, iflags);
1510         for (k = 0; k < sg_dev_max; k++) {
1511                 sdp = sg_dev_arr[k];
1512                 if ((NULL == sdp) || (sdp->device != scsidp))
1513                         continue;       /* dirty but lowers nesting */
1514                 if (sdp->headfp) {
1515                         sdp->detached = 1;
1516                         for (sfp = sdp->headfp; sfp; sfp = tsfp) {
1517                                 tsfp = sfp->nextfp;
1518                                 for (srp = sfp->headrp; srp; srp = tsrp) {
1519                                         tsrp = srp->nextrp;
1520                                         if (sfp->closed || (0 == sg_srp_done(srp, sfp)))
1521                                                 sg_finish_rem_req(srp);
1522                                 }
1523                                 if (sfp->closed) {
1524                                         scsi_device_put(sdp->device);
1525                                         __sg_remove_sfp(sdp, sfp);
1526                                 } else {
1527                                         delay = 1;
1528                                         wake_up_interruptible(&sfp->read_wait);
1529                                         kill_fasync(&sfp->async_qp, SIGPOLL,
1530                                                     POLL_HUP);
1531                                 }
1532                         }
1533                         SCSI_LOG_TIMEOUT(3, printk("sg_detach: dev=%d, dirty\n", k));
1534                         if (NULL == sdp->headfp) {
1535                                 sg_dev_arr[k] = NULL;
1536                         }
1537                 } else {        /* nothing active, simple case */
1538                         SCSI_LOG_TIMEOUT(3, printk("sg_detach: dev=%d\n", k));
1539                         sg_dev_arr[k] = NULL;
1540                 }
1541                 sg_nr_dev--;
1542                 break;
1543         }
1544         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1545
1546         if (sdp) {
1547                 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1548                 class_device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, k));
1549                 cdev_del(sdp->cdev);
1550                 sdp->cdev = NULL;
1551                 put_disk(sdp->disk);
1552                 sdp->disk = NULL;
1553                 if (NULL == sdp->headfp)
1554                         kfree((char *) sdp);
1555         }
1556
1557         if (delay)
1558                 msleep(10);     /* dirty detach so delay device destruction */
1559 }
1560
1561 /* Set 'perm' (4th argument) to 0 to disable module_param's definition
1562  * of sysfs parameters (which module_param doesn't yet support).
1563  * Sysfs parameters defined explicitly below.
1564  */
1565 module_param_named(def_reserved_size, def_reserved_size, int, S_IRUGO);
1566 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1567
1568 MODULE_AUTHOR("Douglas Gilbert");
1569 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1570 MODULE_LICENSE("GPL");
1571 MODULE_VERSION(SG_VERSION_STR);
1572 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1573
1574 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1575 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1576
1577 static int __init
1578 init_sg(void)
1579 {
1580         int rc;
1581
1582         if (def_reserved_size >= 0)
1583                 sg_big_buff = def_reserved_size;
1584
1585         rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1586                                     SG_MAX_DEVS, "sg");
1587         if (rc)
1588                 return rc;
1589         sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1590         if ( IS_ERR(sg_sysfs_class) ) {
1591                 rc = PTR_ERR(sg_sysfs_class);
1592                 goto err_out;
1593         }
1594         sg_sysfs_valid = 1;
1595         rc = scsi_register_interface(&sg_interface);
1596         if (0 == rc) {
1597 #ifdef CONFIG_SCSI_PROC_FS
1598                 sg_proc_init();
1599 #endif                          /* CONFIG_SCSI_PROC_FS */
1600                 return 0;
1601         }
1602         class_destroy(sg_sysfs_class);
1603 err_out:
1604         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1605         return rc;
1606 }
1607
1608 static void __exit
1609 exit_sg(void)
1610 {
1611 #ifdef CONFIG_SCSI_PROC_FS
1612         sg_proc_cleanup();
1613 #endif                          /* CONFIG_SCSI_PROC_FS */
1614         scsi_unregister_interface(&sg_interface);
1615         class_destroy(sg_sysfs_class);
1616         sg_sysfs_valid = 0;
1617         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1618                                  SG_MAX_DEVS);
1619         kfree((char *)sg_dev_arr);
1620         sg_dev_arr = NULL;
1621         sg_dev_max = 0;
1622 }
1623
1624 static int
1625 sg_start_req(Sg_request * srp)
1626 {
1627         int res;
1628         Sg_fd *sfp = srp->parentfp;
1629         sg_io_hdr_t *hp = &srp->header;
1630         int dxfer_len = (int) hp->dxfer_len;
1631         int dxfer_dir = hp->dxfer_direction;
1632         Sg_scatter_hold *req_schp = &srp->data;
1633         Sg_scatter_hold *rsv_schp = &sfp->reserve;
1634
1635         SCSI_LOG_TIMEOUT(4, printk("sg_start_req: dxfer_len=%d\n", dxfer_len));
1636         if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1637                 return 0;
1638         if (sg_allow_dio && (hp->flags & SG_FLAG_DIRECT_IO) &&
1639             (dxfer_dir != SG_DXFER_UNKNOWN) && (0 == hp->iovec_count) &&
1640             (!sfp->parentdp->device->host->unchecked_isa_dma)) {
1641                 res = sg_build_direct(srp, sfp, dxfer_len);
1642                 if (res <= 0)   /* -ve -> error, 0 -> done, 1 -> try indirect */
1643                         return res;
1644         }
1645         if ((!sg_res_in_use(sfp)) && (dxfer_len <= rsv_schp->bufflen))
1646                 sg_link_reserve(sfp, srp, dxfer_len);
1647         else {
1648                 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1649                 if (res) {
1650                         sg_remove_scat(req_schp);
1651                         return res;
1652                 }
1653         }
1654         return 0;
1655 }
1656
1657 static void
1658 sg_finish_rem_req(Sg_request * srp)
1659 {
1660         Sg_fd *sfp = srp->parentfp;
1661         Sg_scatter_hold *req_schp = &srp->data;
1662
1663         SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n", (int) srp->res_used));
1664         if (srp->res_used)
1665                 sg_unlink_reserve(sfp, srp);
1666         else
1667                 sg_remove_scat(req_schp);
1668         sg_remove_request(sfp, srp);
1669 }
1670
1671 static int
1672 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1673 {
1674         int sg_bufflen = tablesize * sizeof(struct scatterlist);
1675         gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1676
1677         /*
1678          * TODO: test without low_dma, we should not need it since
1679          * the block layer will bounce the buffer for us
1680          *
1681          * XXX(hch): we shouldn't need GFP_DMA for the actual S/G list.
1682          */
1683         if (sfp->low_dma)
1684                  gfp_flags |= GFP_DMA;
1685         schp->buffer = kzalloc(sg_bufflen, gfp_flags);
1686         if (!schp->buffer)
1687                 return -ENOMEM;
1688         schp->sglist_len = sg_bufflen;
1689         return tablesize;       /* number of scat_gath elements allocated */
1690 }
1691
1692 #ifdef SG_ALLOW_DIO_CODE
1693 /* vvvvvvvv  following code borrowed from st driver's direct IO vvvvvvvvv */
1694         /* TODO: hopefully we can use the generic block layer code */
1695
1696 /* Pin down user pages and put them into a scatter gather list. Returns <= 0 if
1697    - mapping of all pages not successful
1698    (i.e., either completely successful or fails)
1699 */
1700 static int
1701 st_map_user_pages(struct scatterlist *sgl, const unsigned int max_pages,
1702                   unsigned long uaddr, size_t count, int rw)
1703 {
1704         unsigned long end = (uaddr + count + PAGE_SIZE - 1) >> PAGE_SHIFT;
1705         unsigned long start = uaddr >> PAGE_SHIFT;
1706         const int nr_pages = end - start;
1707         int res, i, j;
1708         struct page **pages;
1709
1710         /* User attempted Overflow! */
1711         if ((uaddr + count) < uaddr)
1712                 return -EINVAL;
1713
1714         /* Too big */
1715         if (nr_pages > max_pages)
1716                 return -ENOMEM;
1717
1718         /* Hmm? */
1719         if (count == 0)
1720                 return 0;
1721
1722         if ((pages = kmalloc(max_pages * sizeof(*pages), GFP_ATOMIC)) == NULL)
1723                 return -ENOMEM;
1724
1725         /* Try to fault in all of the necessary pages */
1726         down_read(&current->mm->mmap_sem);
1727         /* rw==READ means read from drive, write into memory area */
1728         res = get_user_pages(
1729                 current,
1730                 current->mm,
1731                 uaddr,
1732                 nr_pages,
1733                 rw == READ,
1734                 0, /* don't force */
1735                 pages,
1736                 NULL);
1737         up_read(&current->mm->mmap_sem);
1738
1739         /* Errors and no page mapped should return here */
1740         if (res < nr_pages)
1741                 goto out_unmap;
1742
1743         for (i=0; i < nr_pages; i++) {
1744                 /* FIXME: flush superflous for rw==READ,
1745                  * probably wrong function for rw==WRITE
1746                  */
1747                 flush_dcache_page(pages[i]);
1748                 /* ?? Is locking needed? I don't think so */
1749                 /* if (TestSetPageLocked(pages[i]))
1750                    goto out_unlock; */
1751         }
1752
1753         sgl[0].page = pages[0];
1754         sgl[0].offset = uaddr & ~PAGE_MASK;
1755         if (nr_pages > 1) {
1756                 sgl[0].length = PAGE_SIZE - sgl[0].offset;
1757                 count -= sgl[0].length;
1758                 for (i=1; i < nr_pages ; i++) {
1759                         sgl[i].page = pages[i];
1760                         sgl[i].length = count < PAGE_SIZE ? count : PAGE_SIZE;
1761                         count -= PAGE_SIZE;
1762                 }
1763         }
1764         else {
1765                 sgl[0].length = count;
1766         }
1767
1768         kfree(pages);
1769         return nr_pages;
1770
1771  out_unmap:
1772         if (res > 0) {
1773                 for (j=0; j < res; j++)
1774                         page_cache_release(pages[j]);
1775                 res = 0;
1776         }
1777         kfree(pages);
1778         return res;
1779 }
1780
1781
1782 /* And unmap them... */
1783 static int
1784 st_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_pages,
1785                     int dirtied)
1786 {
1787         int i;
1788
1789         for (i=0; i < nr_pages; i++) {
1790                 struct page *page = sgl[i].page;
1791
1792                 if (dirtied)
1793                         SetPageDirty(page);
1794                 /* unlock_page(page); */
1795                 /* FIXME: cache flush missing for rw==READ
1796                  * FIXME: call the correct reference counting function
1797                  */
1798                 page_cache_release(page);
1799         }
1800
1801         return 0;
1802 }
1803
1804 /* ^^^^^^^^  above code borrowed from st driver's direct IO ^^^^^^^^^ */
1805 #endif
1806
1807
1808 /* Returns: -ve -> error, 0 -> done, 1 -> try indirect */
1809 static int
1810 sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len)
1811 {
1812 #ifdef SG_ALLOW_DIO_CODE
1813         sg_io_hdr_t *hp = &srp->header;
1814         Sg_scatter_hold *schp = &srp->data;
1815         int sg_tablesize = sfp->parentdp->sg_tablesize;
1816         int mx_sc_elems, res;
1817         struct scsi_device *sdev = sfp->parentdp->device;
1818
1819         if (((unsigned long)hp->dxferp &
1820                         queue_dma_alignment(sdev->request_queue)) != 0)
1821                 return 1;
1822
1823         mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1824         if (mx_sc_elems <= 0) {
1825                 return 1;
1826         }
1827         res = st_map_user_pages(schp->buffer, mx_sc_elems,
1828                                 (unsigned long)hp->dxferp, dxfer_len,
1829                                 (SG_DXFER_TO_DEV == hp->dxfer_direction) ? 1 : 0);
1830         if (res <= 0)
1831                 return 1;
1832         schp->k_use_sg = res;
1833         schp->dio_in_use = 1;
1834         hp->info |= SG_INFO_DIRECT_IO;
1835         return 0;
1836 #else
1837         return 1;
1838 #endif
1839 }
1840
1841 static int
1842 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1843 {
1844         struct scatterlist *sg;
1845         int ret_sz = 0, k, rem_sz, num, mx_sc_elems;
1846         int sg_tablesize = sfp->parentdp->sg_tablesize;
1847         int blk_size = buff_size;
1848         struct page *p = NULL;
1849
1850         if ((blk_size < 0) || (!sfp))
1851                 return -EFAULT;
1852         if (0 == blk_size)
1853                 ++blk_size;     /* don't know why */
1854 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1855         blk_size = (blk_size + SG_SECTOR_MSK) & (~SG_SECTOR_MSK);
1856         SCSI_LOG_TIMEOUT(4, printk("sg_build_indirect: buff_size=%d, blk_size=%d\n",
1857                                    buff_size, blk_size));
1858
1859         /* N.B. ret_sz carried into this block ... */
1860         mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1861         if (mx_sc_elems < 0)
1862                 return mx_sc_elems;     /* most likely -ENOMEM */
1863
1864         for (k = 0, sg = schp->buffer, rem_sz = blk_size;
1865              (rem_sz > 0) && (k < mx_sc_elems);
1866              ++k, rem_sz -= ret_sz, ++sg) {
1867
1868                 num = (rem_sz > SG_SCATTER_SZ) ? SG_SCATTER_SZ : rem_sz;
1869                 p = sg_page_malloc(num, sfp->low_dma, &ret_sz);
1870                 if (!p)
1871                         return -ENOMEM;
1872
1873                 sg->page = p;
1874                 sg->length = ret_sz;
1875
1876                 SCSI_LOG_TIMEOUT(5, printk("sg_build_build: k=%d, a=0x%p, len=%d\n",
1877                                   k, p, 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, rem_sz=%d\n", k, rem_sz));
1882
1883         schp->bufflen = blk_size;
1884         if (rem_sz > 0) /* must have failed */
1885                 return -ENOMEM;
1886
1887         return 0;
1888 }
1889
1890 static int
1891 sg_write_xfer(Sg_request * srp)
1892 {
1893         sg_io_hdr_t *hp = &srp->header;
1894         Sg_scatter_hold *schp = &srp->data;
1895         struct scatterlist *sg = schp->buffer;
1896         int num_xfer = 0;
1897         int j, k, onum, usglen, ksglen, res;
1898         int iovec_count = (int) hp->iovec_count;
1899         int dxfer_dir = hp->dxfer_direction;
1900         unsigned char *p;
1901         unsigned char __user *up;
1902         int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
1903
1904         if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_TO_DEV == dxfer_dir) ||
1905             (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
1906                 num_xfer = (int) (new_interface ? hp->dxfer_len : hp->flags);
1907                 if (schp->bufflen < num_xfer)
1908                         num_xfer = schp->bufflen;
1909         }
1910         if ((num_xfer <= 0) || (schp->dio_in_use) ||
1911             (new_interface
1912              && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
1913                 return 0;
1914
1915         SCSI_LOG_TIMEOUT(4, printk("sg_write_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
1916                           num_xfer, iovec_count, schp->k_use_sg));
1917         if (iovec_count) {
1918                 onum = iovec_count;
1919                 if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum))
1920                         return -EFAULT;
1921         } else
1922                 onum = 1;
1923
1924         ksglen = sg->length;
1925         p = page_address(sg->page);
1926         for (j = 0, k = 0; j < onum; ++j) {
1927                 res = sg_u_iovec(hp, iovec_count, j, 1, &usglen, &up);
1928                 if (res)
1929                         return res;
1930
1931                 for (; p; ++sg, ksglen = sg->length,
1932                      p = page_address(sg->page)) {
1933                         if (usglen <= 0)
1934                                 break;
1935                         if (ksglen > usglen) {
1936                                 if (usglen >= num_xfer) {
1937                                         if (__copy_from_user(p, up, num_xfer))
1938                                                 return -EFAULT;
1939                                         return 0;
1940                                 }
1941                                 if (__copy_from_user(p, up, usglen))
1942                                         return -EFAULT;
1943                                 p += usglen;
1944                                 ksglen -= usglen;
1945                                 break;
1946                         } else {
1947                                 if (ksglen >= num_xfer) {
1948                                         if (__copy_from_user(p, up, num_xfer))
1949                                                 return -EFAULT;
1950                                         return 0;
1951                                 }
1952                                 if (__copy_from_user(p, up, ksglen))
1953                                         return -EFAULT;
1954                                 up += ksglen;
1955                                 usglen -= ksglen;
1956                         }
1957                         ++k;
1958                         if (k >= schp->k_use_sg)
1959                                 return 0;
1960                 }
1961         }
1962
1963         return 0;
1964 }
1965
1966 static int
1967 sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
1968            int wr_xf, int *countp, unsigned char __user **up)
1969 {
1970         int num_xfer = (int) hp->dxfer_len;
1971         unsigned char __user *p = hp->dxferp;
1972         int count;
1973
1974         if (0 == sg_num) {
1975                 if (wr_xf && ('\0' == hp->interface_id))
1976                         count = (int) hp->flags;        /* holds "old" input_size */
1977                 else
1978                         count = num_xfer;
1979         } else {
1980                 sg_iovec_t iovec;
1981                 if (__copy_from_user(&iovec, p + ind*SZ_SG_IOVEC, SZ_SG_IOVEC))
1982                         return -EFAULT;
1983                 p = iovec.iov_base;
1984                 count = (int) iovec.iov_len;
1985         }
1986         if (!access_ok(wr_xf ? VERIFY_READ : VERIFY_WRITE, p, count))
1987                 return -EFAULT;
1988         if (up)
1989                 *up = p;
1990         if (countp)
1991                 *countp = count;
1992         return 0;
1993 }
1994
1995 static void
1996 sg_remove_scat(Sg_scatter_hold * schp)
1997 {
1998         SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1999         if (schp->buffer && (schp->sglist_len > 0)) {
2000                 struct scatterlist *sg = schp->buffer;
2001
2002                 if (schp->dio_in_use) {
2003 #ifdef SG_ALLOW_DIO_CODE
2004                         st_unmap_user_pages(sg, schp->k_use_sg, TRUE);
2005 #endif
2006                 } else {
2007                         int k;
2008
2009                         for (k = 0; (k < schp->k_use_sg) && sg->page;
2010                              ++k, ++sg) {
2011                                 SCSI_LOG_TIMEOUT(5, printk(
2012                                     "sg_remove_scat: k=%d, a=0x%p, len=%d\n",
2013                                     k, sg->page, sg->length));
2014                                 sg_page_free(sg->page, sg->length);
2015                         }
2016                 }
2017                 kfree(schp->buffer);
2018         }
2019         memset(schp, 0, sizeof (*schp));
2020 }
2021
2022 static int
2023 sg_read_xfer(Sg_request * srp)
2024 {
2025         sg_io_hdr_t *hp = &srp->header;
2026         Sg_scatter_hold *schp = &srp->data;
2027         struct scatterlist *sg = schp->buffer;
2028         int num_xfer = 0;
2029         int j, k, onum, usglen, ksglen, res;
2030         int iovec_count = (int) hp->iovec_count;
2031         int dxfer_dir = hp->dxfer_direction;
2032         unsigned char *p;
2033         unsigned char __user *up;
2034         int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
2035
2036         if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_FROM_DEV == dxfer_dir)
2037             || (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
2038                 num_xfer = hp->dxfer_len;
2039                 if (schp->bufflen < num_xfer)
2040                         num_xfer = schp->bufflen;
2041         }
2042         if ((num_xfer <= 0) || (schp->dio_in_use) ||
2043             (new_interface
2044              && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
2045                 return 0;
2046
2047         SCSI_LOG_TIMEOUT(4, printk("sg_read_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
2048                           num_xfer, iovec_count, schp->k_use_sg));
2049         if (iovec_count) {
2050                 onum = iovec_count;
2051                 if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum))
2052                         return -EFAULT;
2053         } else
2054                 onum = 1;
2055
2056         p = page_address(sg->page);
2057         ksglen = sg->length;
2058         for (j = 0, k = 0; j < onum; ++j) {
2059                 res = sg_u_iovec(hp, iovec_count, j, 0, &usglen, &up);
2060                 if (res)
2061                         return res;
2062
2063                 for (; p; ++sg, ksglen = sg->length,
2064                      p = page_address(sg->page)) {
2065                         if (usglen <= 0)
2066                                 break;
2067                         if (ksglen > usglen) {
2068                                 if (usglen >= num_xfer) {
2069                                         if (__copy_to_user(up, p, num_xfer))
2070                                                 return -EFAULT;
2071                                         return 0;
2072                                 }
2073                                 if (__copy_to_user(up, p, usglen))
2074                                         return -EFAULT;
2075                                 p += usglen;
2076                                 ksglen -= usglen;
2077                                 break;
2078                         } else {
2079                                 if (ksglen >= num_xfer) {
2080                                         if (__copy_to_user(up, p, num_xfer))
2081                                                 return -EFAULT;
2082                                         return 0;
2083                                 }
2084                                 if (__copy_to_user(up, p, ksglen))
2085                                         return -EFAULT;
2086                                 up += ksglen;
2087                                 usglen -= ksglen;
2088                         }
2089                         ++k;
2090                         if (k >= schp->k_use_sg)
2091                                 return 0;
2092                 }
2093         }
2094
2095         return 0;
2096 }
2097
2098 static int
2099 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
2100 {
2101         Sg_scatter_hold *schp = &srp->data;
2102         struct scatterlist *sg = schp->buffer;
2103         int k, num;
2104
2105         SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n",
2106                                    num_read_xfer));
2107         if ((!outp) || (num_read_xfer <= 0))
2108                 return 0;
2109
2110         for (k = 0; (k < schp->k_use_sg) && sg->page; ++k, ++sg) {
2111                 num = sg->length;
2112                 if (num > num_read_xfer) {
2113                         if (__copy_to_user(outp, page_address(sg->page),
2114                                            num_read_xfer))
2115                                 return -EFAULT;
2116                         break;
2117                 } else {
2118                         if (__copy_to_user(outp, page_address(sg->page),
2119                                            num))
2120                                 return -EFAULT;
2121                         num_read_xfer -= num;
2122                         if (num_read_xfer <= 0)
2123                                 break;
2124                         outp += num;
2125                 }
2126         }
2127
2128         return 0;
2129 }
2130
2131 static void
2132 sg_build_reserve(Sg_fd * sfp, int req_size)
2133 {
2134         Sg_scatter_hold *schp = &sfp->reserve;
2135
2136         SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
2137         do {
2138                 if (req_size < PAGE_SIZE)
2139                         req_size = PAGE_SIZE;
2140                 if (0 == sg_build_indirect(schp, sfp, req_size))
2141                         return;
2142                 else
2143                         sg_remove_scat(schp);
2144                 req_size >>= 1; /* divide by 2 */
2145         } while (req_size > (PAGE_SIZE / 2));
2146 }
2147
2148 static void
2149 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2150 {
2151         Sg_scatter_hold *req_schp = &srp->data;
2152         Sg_scatter_hold *rsv_schp = &sfp->reserve;
2153         struct scatterlist *sg = rsv_schp->buffer;
2154         int k, num, rem;
2155
2156         srp->res_used = 1;
2157         SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
2158         rem = size;
2159
2160         for (k = 0; k < rsv_schp->k_use_sg; ++k, ++sg) {
2161                 num = sg->length;
2162                 if (rem <= num) {
2163                         sfp->save_scat_len = num;
2164                         sg->length = rem;
2165                         req_schp->k_use_sg = k + 1;
2166                         req_schp->sglist_len = rsv_schp->sglist_len;
2167                         req_schp->buffer = rsv_schp->buffer;
2168
2169                         req_schp->bufflen = size;
2170                         req_schp->b_malloc_len = rsv_schp->b_malloc_len;
2171                         break;
2172                 } else
2173                         rem -= num;
2174         }
2175
2176         if (k >= rsv_schp->k_use_sg)
2177                 SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
2178 }
2179
2180 static void
2181 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2182 {
2183         Sg_scatter_hold *req_schp = &srp->data;
2184         Sg_scatter_hold *rsv_schp = &sfp->reserve;
2185
2186         SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->k_use_sg=%d\n",
2187                                    (int) req_schp->k_use_sg));
2188         if ((rsv_schp->k_use_sg > 0) && (req_schp->k_use_sg > 0)) {
2189                 struct scatterlist *sg = rsv_schp->buffer;
2190
2191                 if (sfp->save_scat_len > 0)
2192                         (sg + (req_schp->k_use_sg - 1))->length =
2193                             (unsigned) sfp->save_scat_len;
2194                 else
2195                         SCSI_LOG_TIMEOUT(1, printk ("sg_unlink_reserve: BAD save_scat_len\n"));
2196         }
2197         req_schp->k_use_sg = 0;
2198         req_schp->bufflen = 0;
2199         req_schp->buffer = NULL;
2200         req_schp->sglist_len = 0;
2201         sfp->save_scat_len = 0;
2202         srp->res_used = 0;
2203 }
2204
2205 static Sg_request *
2206 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2207 {
2208         Sg_request *resp;
2209         unsigned long iflags;
2210
2211         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2212         for (resp = sfp->headrp; resp; resp = resp->nextrp) {
2213                 /* look for requests that are ready + not SG_IO owned */
2214                 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2215                     ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2216                         resp->done = 2; /* guard against other readers */
2217                         break;
2218                 }
2219         }
2220         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2221         return resp;
2222 }
2223
2224 #ifdef CONFIG_SCSI_PROC_FS
2225 static Sg_request *
2226 sg_get_nth_request(Sg_fd * sfp, int nth)
2227 {
2228         Sg_request *resp;
2229         unsigned long iflags;
2230         int k;
2231
2232         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2233         for (k = 0, resp = sfp->headrp; resp && (k < nth);
2234              ++k, resp = resp->nextrp) ;
2235         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2236         return resp;
2237 }
2238 #endif
2239
2240 /* always adds to end of list */
2241 static Sg_request *
2242 sg_add_request(Sg_fd * sfp)
2243 {
2244         int k;
2245         unsigned long iflags;
2246         Sg_request *resp;
2247         Sg_request *rp = sfp->req_arr;
2248
2249         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2250         resp = sfp->headrp;
2251         if (!resp) {
2252                 memset(rp, 0, sizeof (Sg_request));
2253                 rp->parentfp = sfp;
2254                 resp = rp;
2255                 sfp->headrp = resp;
2256         } else {
2257                 if (0 == sfp->cmd_q)
2258                         resp = NULL;    /* command queuing disallowed */
2259                 else {
2260                         for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2261                                 if (!rp->parentfp)
2262                                         break;
2263                         }
2264                         if (k < SG_MAX_QUEUE) {
2265                                 memset(rp, 0, sizeof (Sg_request));
2266                                 rp->parentfp = sfp;
2267                                 while (resp->nextrp)
2268                                         resp = resp->nextrp;
2269                                 resp->nextrp = rp;
2270                                 resp = rp;
2271                         } else
2272                                 resp = NULL;
2273                 }
2274         }
2275         if (resp) {
2276                 resp->nextrp = NULL;
2277                 resp->header.duration = jiffies_to_msecs(jiffies);
2278         }
2279         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2280         return resp;
2281 }
2282
2283 /* Return of 1 for found; 0 for not found */
2284 static int
2285 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2286 {
2287         Sg_request *prev_rp;
2288         Sg_request *rp;
2289         unsigned long iflags;
2290         int res = 0;
2291
2292         if ((!sfp) || (!srp) || (!sfp->headrp))
2293                 return res;
2294         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2295         prev_rp = sfp->headrp;
2296         if (srp == prev_rp) {
2297                 sfp->headrp = prev_rp->nextrp;
2298                 prev_rp->parentfp = NULL;
2299                 res = 1;
2300         } else {
2301                 while ((rp = prev_rp->nextrp)) {
2302                         if (srp == rp) {
2303                                 prev_rp->nextrp = rp->nextrp;
2304                                 rp->parentfp = NULL;
2305                                 res = 1;
2306                                 break;
2307                         }
2308                         prev_rp = rp;
2309                 }
2310         }
2311         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2312         return res;
2313 }
2314
2315 #ifdef CONFIG_SCSI_PROC_FS
2316 static Sg_fd *
2317 sg_get_nth_sfp(Sg_device * sdp, int nth)
2318 {
2319         Sg_fd *resp;
2320         unsigned long iflags;
2321         int k;
2322
2323         read_lock_irqsave(&sg_dev_arr_lock, iflags);
2324         for (k = 0, resp = sdp->headfp; resp && (k < nth);
2325              ++k, resp = resp->nextfp) ;
2326         read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2327         return resp;
2328 }
2329 #endif
2330
2331 static Sg_fd *
2332 sg_add_sfp(Sg_device * sdp, int dev)
2333 {
2334         Sg_fd *sfp;
2335         unsigned long iflags;
2336
2337         sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2338         if (!sfp)
2339                 return NULL;
2340
2341         init_waitqueue_head(&sfp->read_wait);
2342         rwlock_init(&sfp->rq_list_lock);
2343
2344         sfp->timeout = SG_DEFAULT_TIMEOUT;
2345         sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2346         sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2347         sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
2348             sdp->device->host->unchecked_isa_dma : 1;
2349         sfp->cmd_q = SG_DEF_COMMAND_Q;
2350         sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2351         sfp->parentdp = sdp;
2352         write_lock_irqsave(&sg_dev_arr_lock, iflags);
2353         if (!sdp->headfp)
2354                 sdp->headfp = sfp;
2355         else {                  /* add to tail of existing list */
2356                 Sg_fd *pfp = sdp->headfp;
2357                 while (pfp->nextfp)
2358                         pfp = pfp->nextfp;
2359                 pfp->nextfp = sfp;
2360         }
2361         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2362         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));
2363         sg_build_reserve(sfp, sg_big_buff);
2364         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp:   bufflen=%d, k_use_sg=%d\n",
2365                            sfp->reserve.bufflen, sfp->reserve.k_use_sg));
2366         return sfp;
2367 }
2368
2369 static void
2370 __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2371 {
2372         Sg_fd *fp;
2373         Sg_fd *prev_fp;
2374
2375         prev_fp = sdp->headfp;
2376         if (sfp == prev_fp)
2377                 sdp->headfp = prev_fp->nextfp;
2378         else {
2379                 while ((fp = prev_fp->nextfp)) {
2380                         if (sfp == fp) {
2381                                 prev_fp->nextfp = fp->nextfp;
2382                                 break;
2383                         }
2384                         prev_fp = fp;
2385                 }
2386         }
2387         if (sfp->reserve.bufflen > 0) {
2388                 SCSI_LOG_TIMEOUT(6,
2389                         printk("__sg_remove_sfp:    bufflen=%d, k_use_sg=%d\n",
2390                         (int) sfp->reserve.bufflen, (int) sfp->reserve.k_use_sg));
2391                 if (sfp->mmap_called)
2392                         sg_rb_correct4mmap(&sfp->reserve, 0);   /* undo correction */
2393                 sg_remove_scat(&sfp->reserve);
2394         }
2395         sfp->parentdp = NULL;
2396         SCSI_LOG_TIMEOUT(6, printk("__sg_remove_sfp:    sfp=0x%p\n", sfp));
2397         kfree(sfp);
2398 }
2399
2400 /* Returns 0 in normal case, 1 when detached and sdp object removed */
2401 static int
2402 sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2403 {
2404         Sg_request *srp;
2405         Sg_request *tsrp;
2406         int dirty = 0;
2407         int res = 0;
2408
2409         for (srp = sfp->headrp; srp; srp = tsrp) {
2410                 tsrp = srp->nextrp;
2411                 if (sg_srp_done(srp, sfp))
2412                         sg_finish_rem_req(srp);
2413                 else
2414                         ++dirty;
2415         }
2416         if (0 == dirty) {
2417                 unsigned long iflags;
2418
2419                 write_lock_irqsave(&sg_dev_arr_lock, iflags);
2420                 __sg_remove_sfp(sdp, sfp);
2421                 if (sdp->detached && (NULL == sdp->headfp)) {
2422                         int k, maxd;
2423
2424                         maxd = sg_dev_max;
2425                         for (k = 0; k < maxd; ++k) {
2426                                 if (sdp == sg_dev_arr[k])
2427                                         break;
2428                         }
2429                         if (k < maxd)
2430                                 sg_dev_arr[k] = NULL;
2431                         kfree((char *) sdp);
2432                         res = 1;
2433                 }
2434                 write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2435         } else {
2436                 /* MOD_INC's to inhibit unloading sg and associated adapter driver */
2437                 /* only bump the access_count if we actually succeeded in
2438                  * throwing another counter on the host module */
2439                 scsi_device_get(sdp->device);   /* XXX: retval ignored? */
2440                 sfp->closed = 1;        /* flag dirty state on this fd */
2441                 SCSI_LOG_TIMEOUT(1, printk("sg_remove_sfp: worrisome, %d writes pending\n",
2442                                   dirty));
2443         }
2444         return res;
2445 }
2446
2447 static int
2448 sg_res_in_use(Sg_fd * sfp)
2449 {
2450         const Sg_request *srp;
2451         unsigned long iflags;
2452
2453         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2454         for (srp = sfp->headrp; srp; srp = srp->nextrp)
2455                 if (srp->res_used)
2456                         break;
2457         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2458         return srp ? 1 : 0;
2459 }
2460
2461 /* If retSzp==NULL want exact size or fail */
2462 static struct page *
2463 sg_page_malloc(int rqSz, int lowDma, int *retSzp)
2464 {
2465         struct page *resp = NULL;
2466         gfp_t page_mask;
2467         int order, a_size;
2468         int resSz = rqSz;
2469
2470         if (rqSz <= 0)
2471                 return resp;
2472
2473         if (lowDma)
2474                 page_mask = GFP_ATOMIC | GFP_DMA | __GFP_NOWARN;
2475         else
2476                 page_mask = GFP_ATOMIC | __GFP_NOWARN;
2477
2478         for (order = 0, a_size = PAGE_SIZE; a_size < rqSz;
2479              order++, a_size <<= 1) ;
2480         resp = alloc_pages(page_mask, order);
2481         while ((!resp) && order && retSzp) {
2482                 --order;
2483                 a_size >>= 1;   /* divide by 2, until PAGE_SIZE */
2484                 resp =  alloc_pages(page_mask, order);  /* try half */
2485                 resSz = a_size;
2486         }
2487         if (resp) {
2488                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2489                         memset(page_address(resp), 0, resSz);
2490                 if (retSzp)
2491                         *retSzp = resSz;
2492         }
2493         return resp;
2494 }
2495
2496 static void
2497 sg_page_free(struct page *page, int size)
2498 {
2499         int order, a_size;
2500
2501         if (!page)
2502                 return;
2503         for (order = 0, a_size = PAGE_SIZE; a_size < size;
2504              order++, a_size <<= 1) ;
2505         __free_pages(page, order);
2506 }
2507
2508 #ifndef MAINTENANCE_IN_CMD
2509 #define MAINTENANCE_IN_CMD 0xa3
2510 #endif
2511
2512 static unsigned char allow_ops[] = { TEST_UNIT_READY, REQUEST_SENSE,
2513         INQUIRY, READ_CAPACITY, READ_BUFFER, READ_6, READ_10, READ_12,
2514         READ_16, MODE_SENSE, MODE_SENSE_10, LOG_SENSE, REPORT_LUNS,
2515         SERVICE_ACTION_IN, RECEIVE_DIAGNOSTIC, READ_LONG, MAINTENANCE_IN_CMD
2516 };
2517
2518 static int
2519 sg_allow_access(unsigned char opcode, char dev_type)
2520 {
2521         int k;
2522
2523         if (TYPE_SCANNER == dev_type)   /* TYPE_ROM maybe burner */
2524                 return 1;
2525         for (k = 0; k < sizeof (allow_ops); ++k) {
2526                 if (opcode == allow_ops[k])
2527                         return 1;
2528         }
2529         return 0;
2530 }
2531
2532 #ifdef CONFIG_SCSI_PROC_FS
2533 static int
2534 sg_last_dev(void)
2535 {
2536         int k;
2537         unsigned long iflags;
2538
2539         read_lock_irqsave(&sg_dev_arr_lock, iflags);
2540         for (k = sg_dev_max - 1; k >= 0; --k)
2541                 if (sg_dev_arr[k] && sg_dev_arr[k]->device)
2542                         break;
2543         read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2544         return k + 1;           /* origin 1 */
2545 }
2546 #endif
2547
2548 static Sg_device *
2549 sg_get_dev(int dev)
2550 {
2551         Sg_device *sdp = NULL;
2552         unsigned long iflags;
2553
2554         if (sg_dev_arr && (dev >= 0)) {
2555                 read_lock_irqsave(&sg_dev_arr_lock, iflags);
2556                 if (dev < sg_dev_max)
2557                         sdp = sg_dev_arr[dev];
2558                 read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2559         }
2560         return sdp;
2561 }
2562
2563 #ifdef CONFIG_SCSI_PROC_FS
2564
2565 static struct proc_dir_entry *sg_proc_sgp = NULL;
2566
2567 static char sg_proc_sg_dirname[] = "scsi/sg";
2568
2569 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2570
2571 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2572 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2573                                   size_t count, loff_t *off);
2574 static struct file_operations adio_fops = {
2575         /* .owner, .read and .llseek added in sg_proc_init() */
2576         .open = sg_proc_single_open_adio,
2577         .write = sg_proc_write_adio,
2578         .release = single_release,
2579 };
2580
2581 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2582 static ssize_t sg_proc_write_dressz(struct file *filp,
2583                 const char __user *buffer, size_t count, loff_t *off);
2584 static struct file_operations dressz_fops = {
2585         .open = sg_proc_single_open_dressz,
2586         .write = sg_proc_write_dressz,
2587         .release = single_release,
2588 };
2589
2590 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2591 static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2592 static struct file_operations version_fops = {
2593         .open = sg_proc_single_open_version,
2594         .release = single_release,
2595 };
2596
2597 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2598 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2599 static struct file_operations devhdr_fops = {
2600         .open = sg_proc_single_open_devhdr,
2601         .release = single_release,
2602 };
2603
2604 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2605 static int sg_proc_open_dev(struct inode *inode, struct file *file);
2606 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2607 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2608 static void dev_seq_stop(struct seq_file *s, void *v);
2609 static struct file_operations dev_fops = {
2610         .open = sg_proc_open_dev,
2611         .release = seq_release,
2612 };
2613 static struct seq_operations dev_seq_ops = {
2614         .start = dev_seq_start,
2615         .next  = dev_seq_next,
2616         .stop  = dev_seq_stop,
2617         .show  = sg_proc_seq_show_dev,
2618 };
2619
2620 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2621 static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2622 static struct file_operations devstrs_fops = {
2623         .open = sg_proc_open_devstrs,
2624         .release = seq_release,
2625 };
2626 static struct seq_operations devstrs_seq_ops = {
2627         .start = dev_seq_start,
2628         .next  = dev_seq_next,
2629         .stop  = dev_seq_stop,
2630         .show  = sg_proc_seq_show_devstrs,
2631 };
2632
2633 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2634 static int sg_proc_open_debug(struct inode *inode, struct file *file);
2635 static struct file_operations debug_fops = {
2636         .open = sg_proc_open_debug,
2637         .release = seq_release,
2638 };
2639 static struct seq_operations debug_seq_ops = {
2640         .start = dev_seq_start,
2641         .next  = dev_seq_next,
2642         .stop  = dev_seq_stop,
2643         .show  = sg_proc_seq_show_debug,
2644 };
2645
2646
2647 struct sg_proc_leaf {
2648         const char * name;
2649         struct file_operations * fops;
2650 };
2651
2652 static struct sg_proc_leaf sg_proc_leaf_arr[] = {
2653         {"allow_dio", &adio_fops},
2654         {"debug", &debug_fops},
2655         {"def_reserved_size", &dressz_fops},
2656         {"device_hdr", &devhdr_fops},
2657         {"devices", &dev_fops},
2658         {"device_strs", &devstrs_fops},
2659         {"version", &version_fops}
2660 };
2661
2662 static int
2663 sg_proc_init(void)
2664 {
2665         int k, mask;
2666         int num_leaves =
2667             sizeof (sg_proc_leaf_arr) / sizeof (sg_proc_leaf_arr[0]);
2668         struct proc_dir_entry *pdep;
2669         struct sg_proc_leaf * leaf;
2670
2671         sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2672         if (!sg_proc_sgp)
2673                 return 1;
2674         for (k = 0; k < num_leaves; ++k) {
2675                 leaf = &sg_proc_leaf_arr[k];
2676                 mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2677                 pdep = create_proc_entry(leaf->name, mask, sg_proc_sgp);
2678                 if (pdep) {
2679                         leaf->fops->owner = THIS_MODULE,
2680                         leaf->fops->read = seq_read,
2681                         leaf->fops->llseek = seq_lseek,
2682                         pdep->proc_fops = leaf->fops;
2683                 }
2684         }
2685         return 0;
2686 }
2687
2688 static void
2689 sg_proc_cleanup(void)
2690 {
2691         int k;
2692         int num_leaves =
2693             sizeof (sg_proc_leaf_arr) / sizeof (sg_proc_leaf_arr[0]);
2694
2695         if (!sg_proc_sgp)
2696                 return;
2697         for (k = 0; k < num_leaves; ++k)
2698                 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2699         remove_proc_entry(sg_proc_sg_dirname, NULL);
2700 }
2701
2702
2703 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2704 {
2705         seq_printf(s, "%d\n", *((int *)s->private));
2706         return 0;
2707 }
2708
2709 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2710 {
2711         return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2712 }
2713
2714 static ssize_t
2715 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2716                    size_t count, loff_t *off)
2717 {
2718         int num;
2719         char buff[11];
2720
2721         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2722                 return -EACCES;
2723         num = (count < 10) ? count : 10;
2724         if (copy_from_user(buff, buffer, num))
2725                 return -EFAULT;
2726         buff[num] = '\0';
2727         sg_allow_dio = simple_strtoul(buff, NULL, 10) ? 1 : 0;
2728         return count;
2729 }
2730
2731 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2732 {
2733         return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2734 }
2735
2736 static ssize_t
2737 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2738                      size_t count, loff_t *off)
2739 {
2740         int num;
2741         unsigned long k = ULONG_MAX;
2742         char buff[11];
2743
2744         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2745                 return -EACCES;
2746         num = (count < 10) ? count : 10;
2747         if (copy_from_user(buff, buffer, num))
2748                 return -EFAULT;
2749         buff[num] = '\0';
2750         k = simple_strtoul(buff, NULL, 10);
2751         if (k <= 1048576) {     /* limit "big buff" to 1 MB */
2752                 sg_big_buff = k;
2753                 return count;
2754         }
2755         return -ERANGE;
2756 }
2757
2758 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2759 {
2760         seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2761                    sg_version_date);
2762         return 0;
2763 }
2764
2765 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2766 {
2767         return single_open(file, sg_proc_seq_show_version, NULL);
2768 }
2769
2770 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2771 {
2772         seq_printf(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\t"
2773                    "online\n");
2774         return 0;
2775 }
2776
2777 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2778 {
2779         return single_open(file, sg_proc_seq_show_devhdr, NULL);
2780 }
2781
2782 struct sg_proc_deviter {
2783         loff_t  index;
2784         size_t  max;
2785 };
2786
2787 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2788 {
2789         struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2790
2791         s->private = it;
2792         if (! it)
2793                 return NULL;
2794
2795         if (NULL == sg_dev_arr)
2796                 return NULL;
2797         it->index = *pos;
2798         it->max = sg_last_dev();
2799         if (it->index >= it->max)
2800                 return NULL;
2801         return it;
2802 }
2803
2804 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2805 {
2806         struct sg_proc_deviter * it = s->private;
2807
2808         *pos = ++it->index;
2809         return (it->index < it->max) ? it : NULL;
2810 }
2811
2812 static void dev_seq_stop(struct seq_file *s, void *v)
2813 {
2814         kfree(s->private);
2815 }
2816
2817 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2818 {
2819         return seq_open(file, &dev_seq_ops);
2820 }
2821
2822 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2823 {
2824         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2825         Sg_device *sdp;
2826         struct scsi_device *scsidp;
2827
2828         sdp = it ? sg_get_dev(it->index) : NULL;
2829         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2830                 seq_printf(s, "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n",
2831                               scsidp->host->host_no, scsidp->channel,
2832                               scsidp->id, scsidp->lun, (int) scsidp->type,
2833                               1,
2834                               (int) scsidp->queue_depth,
2835                               (int) scsidp->device_busy,
2836                               (int) scsi_device_online(scsidp));
2837         else
2838                 seq_printf(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2839         return 0;
2840 }
2841
2842 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2843 {
2844         return seq_open(file, &devstrs_seq_ops);
2845 }
2846
2847 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2848 {
2849         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2850         Sg_device *sdp;
2851         struct scsi_device *scsidp;
2852
2853         sdp = it ? sg_get_dev(it->index) : NULL;
2854         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2855                 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2856                            scsidp->vendor, scsidp->model, scsidp->rev);
2857         else
2858                 seq_printf(s, "<no active device>\n");
2859         return 0;
2860 }
2861
2862 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2863 {
2864         int k, m, new_interface, blen, usg;
2865         Sg_request *srp;
2866         Sg_fd *fp;
2867         const sg_io_hdr_t *hp;
2868         const char * cp;
2869         unsigned int ms;
2870
2871         for (k = 0; (fp = sg_get_nth_sfp(sdp, k)); ++k) {
2872                 seq_printf(s, "   FD(%d): timeout=%dms bufflen=%d "
2873                            "(res)sgat=%d low_dma=%d\n", k + 1,
2874                            jiffies_to_msecs(fp->timeout),
2875                            fp->reserve.bufflen,
2876                            (int) fp->reserve.k_use_sg,
2877                            (int) fp->low_dma);
2878                 seq_printf(s, "   cmd_q=%d f_packid=%d k_orphan=%d closed=%d\n",
2879                            (int) fp->cmd_q, (int) fp->force_packid,
2880                            (int) fp->keep_orphan, (int) fp->closed);
2881                 for (m = 0; (srp = sg_get_nth_request(fp, m)); ++m) {
2882                         hp = &srp->header;
2883                         new_interface = (hp->interface_id == '\0') ? 0 : 1;
2884                         if (srp->res_used) {
2885                                 if (new_interface &&
2886                                     (SG_FLAG_MMAP_IO & hp->flags))
2887                                         cp = "     mmap>> ";
2888                                 else
2889                                         cp = "     rb>> ";
2890                         } else {
2891                                 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2892                                         cp = "     dio>> ";
2893                                 else
2894                                         cp = "     ";
2895                         }
2896                         seq_printf(s, cp);
2897                         blen = srp->data.bufflen;
2898                         usg = srp->data.k_use_sg;
2899                         seq_printf(s, srp->done ?
2900                                    ((1 == srp->done) ?  "rcv:" : "fin:")
2901                                    : "act:");
2902                         seq_printf(s, " id=%d blen=%d",
2903                                    srp->header.pack_id, blen);
2904                         if (srp->done)
2905                                 seq_printf(s, " dur=%d", hp->duration);
2906                         else {
2907                                 ms = jiffies_to_msecs(jiffies);
2908                                 seq_printf(s, " t_o/elap=%d/%d",
2909                                         (new_interface ? hp->timeout :
2910                                                   jiffies_to_msecs(fp->timeout)),
2911                                         (ms > hp->duration ? ms - hp->duration : 0));
2912                         }
2913                         seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2914                                    (int) srp->data.cmd_opcode);
2915                 }
2916                 if (0 == m)
2917                         seq_printf(s, "     No requests active\n");
2918         }
2919 }
2920
2921 static int sg_proc_open_debug(struct inode *inode, struct file *file)
2922 {
2923         return seq_open(file, &debug_seq_ops);
2924 }
2925
2926 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2927 {
2928         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2929         Sg_device *sdp;
2930
2931         if (it && (0 == it->index)) {
2932                 seq_printf(s, "dev_max(currently)=%d max_active_device=%d "
2933                            "(origin 1)\n", sg_dev_max, (int)it->max);
2934                 seq_printf(s, " def_reserved_size=%d\n", sg_big_buff);
2935         }
2936         sdp = it ? sg_get_dev(it->index) : NULL;
2937         if (sdp) {
2938                 struct scsi_device *scsidp = sdp->device;
2939
2940                 if (NULL == scsidp) {
2941                         seq_printf(s, "device %d detached ??\n",
2942                                    (int)it->index);
2943                         return 0;
2944                 }
2945
2946                 if (sg_get_nth_sfp(sdp, 0)) {
2947                         seq_printf(s, " >>> device=%s ",
2948                                 sdp->disk->disk_name);
2949                         if (sdp->detached)
2950                                 seq_printf(s, "detached pending close ");
2951                         else
2952                                 seq_printf
2953                                     (s, "scsi%d chan=%d id=%d lun=%d   em=%d",
2954                                      scsidp->host->host_no,
2955                                      scsidp->channel, scsidp->id,
2956                                      scsidp->lun,
2957                                      scsidp->host->hostt->emulated);
2958                         seq_printf(s, " sg_tablesize=%d excl=%d\n",
2959                                    sdp->sg_tablesize, sdp->exclude);
2960                 }
2961                 sg_proc_debug_helper(s, sdp);
2962         }
2963         return 0;
2964 }
2965
2966 #endif                          /* CONFIG_SCSI_PROC_FS */
2967
2968 module_init(init_sg);
2969 module_exit(exit_sg);