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   1 /*
   2  *  History:
   3  *  Started: Aug 9 by Lawrence Foard (entropy@world.std.com),
   4  *           to allow user process control of SCSI devices.
   5  *  Development Sponsored by Killy Corp. NY NY
   6  *
   7  * Original driver (sg.c):
   8  *        Copyright (C) 1992 Lawrence Foard
   9  * Version 2 and 3 extensions to driver:
  10  *        Copyright (C) 1998 - 2005 Douglas Gilbert
  11  *
  12  *  Modified  19-JAN-1998  Richard Gooch <rgooch@atnf.csiro.au>  Devfs support
  13  *
  14  * This program is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2, or (at your option)
  17  * any later version.
  18  *
  19  */
  20
  21 static int sg_version_num = 30534;      /* 2 digits for each component */
  22 #define SG_VERSION_STR "3.5.34"
  23
  24 /*
  25  *  D. P. Gilbert (dgilbert@interlog.com, dougg@triode.net.au), notes:
  26  *      - scsi logging is available via SCSI_LOG_TIMEOUT macros. First
  27  *        the kernel/module needs to be built with CONFIG_SCSI_LOGGING
  28  *        (otherwise the macros compile to empty statements).
  29  *
  30  */
  31 #include <linux/module.h>
  32
  33 #include <linux/fs.h>
  34 #include <linux/kernel.h>
  35 #include <linux/sched.h>
  36 #include <linux/string.h>
  37 #include <linux/mm.h>
  38 #include <linux/errno.h>
  39 #include <linux/mtio.h>
  40 #include <linux/ioctl.h>
  41 #include <linux/fcntl.h>
  42 #include <linux/init.h>
  43 #include <linux/poll.h>
  44 #include <linux/moduleparam.h>
  45 #include <linux/cdev.h>
  46 #include <linux/idr.h>
  47 #include <linux/seq_file.h>
  48 #include <linux/blkdev.h>
  49 #include <linux/delay.h>
  50 #include <linux/scatterlist.h>
  51 #include <linux/blktrace_api.h>
  52 #include <linux/smp_lock.h>
  53
  54 #include "scsi.h"
  55 #include <scsi/scsi_dbg.h>
  56 #include <scsi/scsi_host.h>
  57 #include <scsi/scsi_driver.h>
  58 #include <scsi/scsi_ioctl.h>
  59 #include <scsi/sg.h>
  60
  61 #include "scsi_logging.h"
  62
  63 #ifdef CONFIG_SCSI_PROC_FS
  64 #include <linux/proc_fs.h>
  65 static char *sg_version_date = "20061027";
  66
  67 static int sg_proc_init(void);
  68 static void sg_proc_cleanup(void);
  69 #endif
  70
  71 #define SG_ALLOW_DIO_DEF 0
  72 #define SG_ALLOW_DIO_CODE /* compile out by commenting this define */
  73
  74 #define SG_MAX_DEVS 32768
  75
  76 /*
  77  * Suppose you want to calculate the formula muldiv(x,m,d)=int(x * m / d)
  78  * Then when using 32 bit integers x * m may overflow during the calculation.
  79  * Replacing muldiv(x) by muldiv(x)=((x % d) * m) / d + int(x / d) * m
  80  * calculates the same, but prevents the overflow when both m and d
  81  * are "small" numbers (like HZ and USER_HZ).
  82  * Of course an overflow is inavoidable if the result of muldiv doesn't fit
  83  * in 32 bits.
  84  */
  85 #define MULDIV(X,MUL,DIV) ((((X % DIV) * MUL) / DIV) + ((X / DIV) * MUL))
  86
  87 #define SG_DEFAULT_TIMEOUT MULDIV(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
  88
  89 int sg_big_buff = SG_DEF_RESERVED_SIZE;
  90 /* N.B. This variable is readable and writeable via
  91    /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
  92    of this size (or less if there is not enough memory) will be reserved
  93    for use by this file descriptor. [Deprecated usage: this variable is also
  94    readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
  95    the kernel (i.e. it is not a module).] */
  96 static int def_reserved_size = -1;      /* picks up init parameter */
  97 static int sg_allow_dio = SG_ALLOW_DIO_DEF;
  98
  99 static int scatter_elem_sz = SG_SCATTER_SZ;
 100 static int scatter_elem_sz_prev = SG_SCATTER_SZ;
 101
 102 #define SG_SECTOR_SZ 512
 103 #define SG_SECTOR_MSK (SG_SECTOR_SZ - 1)
 104
 105 static int sg_add(struct device *, struct class_interface *);
 106 static void sg_remove(struct device *, struct class_interface *);
 107
 108 static DEFINE_IDR(sg_index_idr);
 109 static DEFINE_RWLOCK(sg_index_lock);    /* Also used to lock
 110                                                            file descriptor list for device */
 111
 112 static struct class_interface sg_interface = {
 113         .add_dev        = sg_add,
 114         .remove_dev     = sg_remove,
 115 };
 116
 117 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
 118         unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
 119         unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */
 120         unsigned bufflen;       /* Size of (aggregate) data buffer */
 121         unsigned b_malloc_len;  /* actual len malloc'ed in buffer */
 122         struct scatterlist *buffer;/* scatter list */
 123         char dio_in_use;        /* 0->indirect IO (or mmap), 1->dio */
 124         unsigned char cmd_opcode; /* first byte of command */
 125 } Sg_scatter_hold;
 126
 127 struct sg_device;               /* forward declarations */
 128 struct sg_fd;
 129
 130 typedef struct sg_request {     /* SG_MAX_QUEUE requests outstanding per file */
 131         struct sg_request *nextrp;      /* NULL -> tail request (slist) */
 132         struct sg_fd *parentfp; /* NULL -> not in use */
 133         Sg_scatter_hold data;   /* hold buffer, perhaps scatter list */
 134         sg_io_hdr_t header;     /* scsi command+info, see <scsi/sg.h> */
 135         unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
 136         char res_used;          /* 1 -> using reserve buffer, 0 -> not ... */
 137         char orphan;            /* 1 -> drop on sight, 0 -> normal */
 138         char sg_io_owned;       /* 1 -> packet belongs to SG_IO */
 139         volatile char done;     /* 0->before bh, 1->before read, 2->read */
 140 } Sg_request;
 141
 142 typedef struct sg_fd {          /* holds the state of a file descriptor */
 143         struct sg_fd *nextfp;   /* NULL when last opened fd on this device */
 144         struct sg_device *parentdp;     /* owning device */
 145         wait_queue_head_t read_wait;    /* queue read until command done */
 146         rwlock_t rq_list_lock;  /* protect access to list in req_arr */
 147         int timeout;            /* defaults to SG_DEFAULT_TIMEOUT      */
 148         int timeout_user;       /* defaults to SG_DEFAULT_TIMEOUT_USER */
 149         Sg_scatter_hold reserve;        /* buffer held for this file descriptor */
 150         unsigned save_scat_len; /* original length of trunc. scat. element */
 151         Sg_request *headrp;     /* head of request slist, NULL->empty */
 152         struct fasync_struct *async_qp; /* used by asynchronous notification */
 153         Sg_request req_arr[SG_MAX_QUEUE];       /* used as singly-linked list */
 154         char low_dma;           /* as in parent but possibly overridden to 1 */
 155         char force_packid;      /* 1 -> pack_id input to read(), 0 -> ignored */
 156         volatile char closed;   /* 1 -> fd closed but request(s) outstanding */
 157         char cmd_q;             /* 1 -> allow command queuing, 0 -> don't */
 158         char next_cmd_len;      /* 0 -> automatic (def), >0 -> use on next write() */
 159         char keep_orphan;       /* 0 -> drop orphan (def), 1 -> keep for read() */
 160         char mmap_called;       /* 0 -> mmap() never called on this fd */
 161 } Sg_fd;
 162
 163 typedef struct sg_device { /* holds the state of each scsi generic device */
 164         struct scsi_device *device;
 165         wait_queue_head_t o_excl_wait;  /* queue open() when O_EXCL in use */
 166         int sg_tablesize;       /* adapter's max scatter-gather table size */
 167         u32 index;              /* device index number */
 168         Sg_fd *headfp;          /* first open fd belonging to this device */
 169         volatile char detached; /* 0->attached, 1->detached pending removal */
 170         volatile char exclude;  /* opened for exclusive access */
 171         char sgdebug;           /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
 172         struct gendisk *disk;
 173         struct cdev * cdev;     /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
 174 } Sg_device;
 175
 176 static int sg_fasync(int fd, struct file *filp, int mode);
 177 /* tasklet or soft irq callback */
 178 static void sg_cmd_done(void *data, char *sense, int result, int resid);
 179 static int sg_start_req(Sg_request * srp);
 180 static void sg_finish_rem_req(Sg_request * srp);
 181 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
 182 static int sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp,
 183                          int tablesize);
 184 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
 185                            Sg_request * srp);
 186 static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
 187                         const char __user *buf, size_t count, int blocking,
 188                         int read_only, Sg_request **o_srp);
 189 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
 190                            unsigned char *cmnd, int timeout, int blocking);
 191 static int sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
 192                       int wr_xf, int *countp, unsigned char __user **up);
 193 static int sg_write_xfer(Sg_request * srp);
 194 static int sg_read_xfer(Sg_request * srp);
 195 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
 196 static void sg_remove_scat(Sg_scatter_hold * schp);
 197 static void sg_build_reserve(Sg_fd * sfp, int req_size);
 198 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
 199 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
 200 static struct page *sg_page_malloc(int rqSz, int lowDma, int *retSzp);
 201 static void sg_page_free(struct page *page, int size);
 202 static Sg_fd *sg_add_sfp(Sg_device * sdp, int dev);
 203 static int sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
 204 static void __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
 205 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
 206 static Sg_request *sg_add_request(Sg_fd * sfp);
 207 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
 208 static int sg_res_in_use(Sg_fd * sfp);
 209 static int sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len);
 210 static Sg_device *sg_get_dev(int dev);
 211 #ifdef CONFIG_SCSI_PROC_FS
 212 static int sg_last_dev(void);
 213 #endif
 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         lock_kernel();
 232         nonseekable_open(inode, filp);
 233         SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags));
 234         sdp = sg_get_dev(dev);
 235         if ((!sdp) || (!sdp->device)) {
 236                 unlock_kernel();
 237                 return -ENXIO;
 238         }
 239         if (sdp->detached) {
 240                 unlock_kernel();
 241                 return -ENODEV;
 242         }
 243
 244         /* This driver's module count bumped by fops_get in <linux/fs.h> */
 245         /* Prevent the device driver from vanishing while we sleep */
 246         retval = scsi_device_get(sdp->device);
 247         if (retval) {
 248                 unlock_kernel();
 249                 return retval;
 250         }
 251
 252         if (!((flags & O_NONBLOCK) ||
 253               scsi_block_when_processing_errors(sdp->device))) {
 254                 retval = -ENXIO;
 255                 /* we are in error recovery for this device */
 256                 goto error_out;
 257         }
 258
 259         if (flags & O_EXCL) {
 260                 if (O_RDONLY == (flags & O_ACCMODE)) {
 261                         retval = -EPERM; /* Can't lock it with read only access */
 262                         goto error_out;
 263                 }
 264                 if (sdp->headfp && (flags & O_NONBLOCK)) {
 265                         retval = -EBUSY;
 266                         goto error_out;
 267                 }
 268                 res = 0;
 269                 __wait_event_interruptible(sdp->o_excl_wait,
 270                         ((sdp->headfp || sdp->exclude) ? 0 : (sdp->exclude = 1)), res);
 271                 if (res) {
 272                         retval = res;   /* -ERESTARTSYS because signal hit process */
 273                         goto error_out;
 274                 }
 275         } else if (sdp->exclude) {      /* some other fd has an exclusive lock on dev */
 276                 if (flags & O_NONBLOCK) {
 277                         retval = -EBUSY;
 278                         goto error_out;
 279                 }
 280                 res = 0;
 281                 __wait_event_interruptible(sdp->o_excl_wait, (!sdp->exclude),
 282                                            res);
 283                 if (res) {
 284                         retval = res;   /* -ERESTARTSYS because signal hit process */
 285                         goto error_out;
 286                 }
 287         }
 288         if (sdp->detached) {
 289                 retval = -ENODEV;
 290                 goto error_out;
 291         }
 292         if (!sdp->headfp) {     /* no existing opens on this device */
 293                 sdp->sgdebug = 0;
 294                 q = sdp->device->request_queue;
 295                 sdp->sg_tablesize = min(q->max_hw_segments,
 296                                         q->max_phys_segments);
 297         }
 298         if ((sfp = sg_add_sfp(sdp, dev)))
 299                 filp->private_data = sfp;
 300         else {
 301                 if (flags & O_EXCL)
 302                         sdp->exclude = 0;       /* undo if error */
 303                 retval = -ENOMEM;
 304                 goto error_out;
 305         }
 306         unlock_kernel();
 307         return 0;
 308
 309       error_out:
 310         scsi_device_put(sdp->device);
 311         unlock_kernel();
 312         return retval;
 313 }
 314
 315 /* Following function was formerly called 'sg_close' */
 316 static int
 317 sg_release(struct inode *inode, struct file *filp)
 318 {
 319         Sg_device *sdp;
 320         Sg_fd *sfp;
 321
 322         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 323                 return -ENXIO;
 324         SCSI_LOG_TIMEOUT(3, printk("sg_release: %s\n", sdp->disk->disk_name));
 325         sg_fasync(-1, filp, 0); /* remove filp from async notification list */
 326         if (0 == sg_remove_sfp(sdp, sfp)) {     /* Returns 1 when sdp gone */
 327                 if (!sdp->detached) {
 328                         scsi_device_put(sdp->device);
 329                 }
 330                 sdp->exclude = 0;
 331                 wake_up_interruptible(&sdp->o_excl_wait);
 332         }
 333         return 0;
 334 }
 335
 336 static ssize_t
 337 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
 338 {
 339         Sg_device *sdp;
 340         Sg_fd *sfp;
 341         Sg_request *srp;
 342         int req_pack_id = -1;
 343         sg_io_hdr_t *hp;
 344         struct sg_header *old_hdr = NULL;
 345         int retval = 0;
 346
 347         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 348                 return -ENXIO;
 349         SCSI_LOG_TIMEOUT(3, printk("sg_read: %s, count=%d\n",
 350                                    sdp->disk->disk_name, (int) count));
 351
 352         if (!access_ok(VERIFY_WRITE, buf, count))
 353                 return -EFAULT;
 354         if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
 355                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 356                 if (!old_hdr)
 357                         return -ENOMEM;
 358                 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
 359                         retval = -EFAULT;
 360                         goto free_old_hdr;
 361                 }
 362                 if (old_hdr->reply_len < 0) {
 363                         if (count >= SZ_SG_IO_HDR) {
 364                                 sg_io_hdr_t *new_hdr;
 365                                 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
 366                                 if (!new_hdr) {
 367                                         retval = -ENOMEM;
 368                                         goto free_old_hdr;
 369                                 }
 370                                 retval =__copy_from_user
 371                                     (new_hdr, buf, SZ_SG_IO_HDR);
 372                                 req_pack_id = new_hdr->pack_id;
 373                                 kfree(new_hdr);
 374                                 if (retval) {
 375                                         retval = -EFAULT;
 376                                         goto free_old_hdr;
 377                                 }
 378                         }
 379                 } else
 380                         req_pack_id = old_hdr->pack_id;
 381         }
 382         srp = sg_get_rq_mark(sfp, req_pack_id);
 383         if (!srp) {             /* now wait on packet to arrive */
 384                 if (sdp->detached) {
 385                         retval = -ENODEV;
 386                         goto free_old_hdr;
 387                 }
 388                 if (filp->f_flags & O_NONBLOCK) {
 389                         retval = -EAGAIN;
 390                         goto free_old_hdr;
 391                 }
 392                 while (1) {
 393                         retval = 0; /* following macro beats race condition */
 394                         __wait_event_interruptible(sfp->read_wait,
 395                                 (sdp->detached ||
 396                                 (srp = sg_get_rq_mark(sfp, req_pack_id))),
 397                                 retval);
 398                         if (sdp->detached) {
 399                                 retval = -ENODEV;
 400                                 goto free_old_hdr;
 401                         }
 402                         if (0 == retval)
 403                                 break;
 404
 405                         /* -ERESTARTSYS as signal hit process */
 406                         goto free_old_hdr;
 407                 }
 408         }
 409         if (srp->header.interface_id != '\0') {
 410                 retval = sg_new_read(sfp, buf, count, srp);
 411                 goto free_old_hdr;
 412         }
 413
 414         hp = &srp->header;
 415         if (old_hdr == NULL) {
 416                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 417                 if (! old_hdr) {
 418                         retval = -ENOMEM;
 419                         goto free_old_hdr;
 420                 }
 421         }
 422         memset(old_hdr, 0, SZ_SG_HEADER);
 423         old_hdr->reply_len = (int) hp->timeout;
 424         old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
 425         old_hdr->pack_id = hp->pack_id;
 426         old_hdr->twelve_byte =
 427             ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
 428         old_hdr->target_status = hp->masked_status;
 429         old_hdr->host_status = hp->host_status;
 430         old_hdr->driver_status = hp->driver_status;
 431         if ((CHECK_CONDITION & hp->masked_status) ||
 432             (DRIVER_SENSE & hp->driver_status))
 433                 memcpy(old_hdr->sense_buffer, srp->sense_b,
 434                        sizeof (old_hdr->sense_buffer));
 435         switch (hp->host_status) {
 436         /* This setup of 'result' is for backward compatibility and is best
 437            ignored by the user who should use target, host + driver status */
 438         case DID_OK:
 439         case DID_PASSTHROUGH:
 440         case DID_SOFT_ERROR:
 441                 old_hdr->result = 0;
 442                 break;
 443         case DID_NO_CONNECT:
 444         case DID_BUS_BUSY:
 445         case DID_TIME_OUT:
 446                 old_hdr->result = EBUSY;
 447                 break;
 448         case DID_BAD_TARGET:
 449         case DID_ABORT:
 450         case DID_PARITY:
 451         case DID_RESET:
 452         case DID_BAD_INTR:
 453                 old_hdr->result = EIO;
 454                 break;
 455         case DID_ERROR:
 456                 old_hdr->result = (srp->sense_b[0] == 0 &&
 457                                   hp->masked_status == GOOD) ? 0 : EIO;
 458                 break;
 459         default:
 460                 old_hdr->result = EIO;
 461                 break;
 462         }
 463
 464         /* Now copy the result back to the user buffer.  */
 465         if (count >= SZ_SG_HEADER) {
 466                 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
 467                         retval = -EFAULT;
 468                         goto free_old_hdr;
 469                 }
 470                 buf += SZ_SG_HEADER;
 471                 if (count > old_hdr->reply_len)
 472                         count = old_hdr->reply_len;
 473                 if (count > SZ_SG_HEADER) {
 474                         if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
 475                                 retval = -EFAULT;
 476                                 goto free_old_hdr;
 477                         }
 478                 }
 479         } else
 480                 count = (old_hdr->result == 0) ? 0 : -EIO;
 481         sg_finish_rem_req(srp);
 482         retval = count;
 483 free_old_hdr:
 484         kfree(old_hdr);
 485         return retval;
 486 }
 487
 488 static ssize_t
 489 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
 490 {
 491         sg_io_hdr_t *hp = &srp->header;
 492         int err = 0;
 493         int len;
 494
 495         if (count < SZ_SG_IO_HDR) {
 496                 err = -EINVAL;
 497                 goto err_out;
 498         }
 499         hp->sb_len_wr = 0;
 500         if ((hp->mx_sb_len > 0) && hp->sbp) {
 501                 if ((CHECK_CONDITION & hp->masked_status) ||
 502                     (DRIVER_SENSE & hp->driver_status)) {
 503                         int sb_len = SCSI_SENSE_BUFFERSIZE;
 504                         sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
 505                         len = 8 + (int) srp->sense_b[7];        /* Additional sense length field */
 506                         len = (len > sb_len) ? sb_len : len;
 507                         if (copy_to_user(hp->sbp, srp->sense_b, len)) {
 508                                 err = -EFAULT;
 509                                 goto err_out;
 510                         }
 511                         hp->sb_len_wr = len;
 512                 }
 513         }
 514         if (hp->masked_status || hp->host_status || hp->driver_status)
 515                 hp->info |= SG_INFO_CHECK;
 516         if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
 517                 err = -EFAULT;
 518                 goto err_out;
 519         }
 520         err = sg_read_xfer(srp);
 521       err_out:
 522         sg_finish_rem_req(srp);
 523         return (0 == err) ? count : err;
 524 }
 525
 526 static ssize_t
 527 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
 528 {
 529         int mxsize, cmd_size, k;
 530         int input_size, blocking;
 531         unsigned char opcode;
 532         Sg_device *sdp;
 533         Sg_fd *sfp;
 534         Sg_request *srp;
 535         struct sg_header old_hdr;
 536         sg_io_hdr_t *hp;
 537         unsigned char cmnd[MAX_COMMAND_SIZE];
 538
 539         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 540                 return -ENXIO;
 541         SCSI_LOG_TIMEOUT(3, printk("sg_write: %s, count=%d\n",
 542                                    sdp->disk->disk_name, (int) count));
 543         if (sdp->detached)
 544                 return -ENODEV;
 545         if (!((filp->f_flags & O_NONBLOCK) ||
 546               scsi_block_when_processing_errors(sdp->device)))
 547                 return -ENXIO;
 548
 549         if (!access_ok(VERIFY_READ, buf, count))
 550                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 551         if (count < SZ_SG_HEADER)
 552                 return -EIO;
 553         if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
 554                 return -EFAULT;
 555         blocking = !(filp->f_flags & O_NONBLOCK);
 556         if (old_hdr.reply_len < 0)
 557                 return sg_new_write(sfp, filp, buf, count, blocking, 0, NULL);
 558         if (count < (SZ_SG_HEADER + 6))
 559                 return -EIO;    /* The minimum scsi command length is 6 bytes. */
 560
 561         if (!(srp = sg_add_request(sfp))) {
 562                 SCSI_LOG_TIMEOUT(1, printk("sg_write: queue full\n"));
 563                 return -EDOM;
 564         }
 565         buf += SZ_SG_HEADER;
 566         __get_user(opcode, buf);
 567         if (sfp->next_cmd_len > 0) {
 568                 if (sfp->next_cmd_len > MAX_COMMAND_SIZE) {
 569                         SCSI_LOG_TIMEOUT(1, printk("sg_write: command length too long\n"));
 570                         sfp->next_cmd_len = 0;
 571                         sg_remove_request(sfp, srp);
 572                         return -EIO;
 573                 }
 574                 cmd_size = sfp->next_cmd_len;
 575                 sfp->next_cmd_len = 0;  /* reset so only this write() effected */
 576         } else {
 577                 cmd_size = COMMAND_SIZE(opcode);        /* based on SCSI command group */
 578                 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
 579                         cmd_size = 12;
 580         }
 581         SCSI_LOG_TIMEOUT(4, printk(
 582                 "sg_write:   scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
 583 /* Determine buffer size.  */
 584         input_size = count - cmd_size;
 585         mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
 586         mxsize -= SZ_SG_HEADER;
 587         input_size -= SZ_SG_HEADER;
 588         if (input_size < 0) {
 589                 sg_remove_request(sfp, srp);
 590                 return -EIO;    /* User did not pass enough bytes for this command. */
 591         }
 592         hp = &srp->header;
 593         hp->interface_id = '\0';        /* indicator of old interface tunnelled */
 594         hp->cmd_len = (unsigned char) cmd_size;
 595         hp->iovec_count = 0;
 596         hp->mx_sb_len = 0;
 597         if (input_size > 0)
 598                 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
 599                     SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
 600         else
 601                 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
 602         hp->dxfer_len = mxsize;
 603         hp->dxferp = (char __user *)buf + cmd_size;
 604         hp->sbp = NULL;
 605         hp->timeout = old_hdr.reply_len;        /* structure abuse ... */
 606         hp->flags = input_size; /* structure abuse ... */
 607         hp->pack_id = old_hdr.pack_id;
 608         hp->usr_ptr = NULL;
 609         if (__copy_from_user(cmnd, buf, cmd_size))
 610                 return -EFAULT;
 611         /*
 612          * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
 613          * but is is possible that the app intended SG_DXFER_TO_DEV, because there
 614          * is a non-zero input_size, so emit a warning.
 615          */
 616         if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
 617                 static char cmd[TASK_COMM_LEN];
 618                 if (strcmp(current->comm, cmd) && printk_ratelimit()) {
 619                         printk(KERN_WARNING
 620                                "sg_write: data in/out %d/%d bytes for SCSI command 0x%x--"
 621                                "guessing data in;\n" KERN_WARNING "   "
 622                                "program %s not setting count and/or reply_len properly\n",
 623                                old_hdr.reply_len - (int)SZ_SG_HEADER,
 624                                input_size, (unsigned int) cmnd[0],
 625                                current->comm);
 626                         strcpy(cmd, current->comm);
 627                 }
 628         }
 629         k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
 630         return (k < 0) ? k : count;
 631 }
 632
 633 static ssize_t
 634 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
 635                  size_t count, int blocking, int read_only,
 636                  Sg_request **o_srp)
 637 {
 638         int k;
 639         Sg_request *srp;
 640         sg_io_hdr_t *hp;
 641         unsigned char cmnd[MAX_COMMAND_SIZE];
 642         int timeout;
 643         unsigned long ul_timeout;
 644         struct request_queue *q;
 645
 646         if (count < SZ_SG_IO_HDR)
 647                 return -EINVAL;
 648         if (!access_ok(VERIFY_READ, buf, count))
 649                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 650
 651         sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
 652         if (!(srp = sg_add_request(sfp))) {
 653                 SCSI_LOG_TIMEOUT(1, printk("sg_new_write: queue full\n"));
 654                 return -EDOM;
 655         }
 656         hp = &srp->header;
 657         if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
 658                 sg_remove_request(sfp, srp);
 659                 return -EFAULT;
 660         }
 661         if (hp->interface_id != 'S') {
 662                 sg_remove_request(sfp, srp);
 663                 return -ENOSYS;
 664         }
 665         if (hp->flags & SG_FLAG_MMAP_IO) {
 666                 if (hp->dxfer_len > sfp->reserve.bufflen) {
 667                         sg_remove_request(sfp, srp);
 668                         return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
 669                 }
 670                 if (hp->flags & SG_FLAG_DIRECT_IO) {
 671                         sg_remove_request(sfp, srp);
 672                         return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
 673                 }
 674                 if (sg_res_in_use(sfp)) {
 675                         sg_remove_request(sfp, srp);
 676                         return -EBUSY;  /* reserve buffer already being used */
 677                 }
 678         }
 679         ul_timeout = msecs_to_jiffies(srp->header.timeout);
 680         timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
 681         if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
 682                 sg_remove_request(sfp, srp);
 683                 return -EMSGSIZE;
 684         }
 685         if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
 686                 sg_remove_request(sfp, srp);
 687                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 688         }
 689         if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
 690                 sg_remove_request(sfp, srp);
 691                 return -EFAULT;
 692         }
 693         q = sfp->parentdp->device->request_queue;
 694         if (read_only && blk_verify_command(&q->cmd_filter, cmnd,
 695                                             file->f_mode & FMODE_WRITE)) {
 696                 sg_remove_request(sfp, srp);
 697                 return -EPERM;
 698         }
 699         k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
 700         if (k < 0)
 701                 return k;
 702         if (o_srp)
 703                 *o_srp = srp;
 704         return count;
 705 }
 706
 707 static int
 708 sg_common_write(Sg_fd * sfp, Sg_request * srp,
 709                 unsigned char *cmnd, int timeout, int blocking)
 710 {
 711         int k, data_dir;
 712         Sg_device *sdp = sfp->parentdp;
 713         sg_io_hdr_t *hp = &srp->header;
 714
 715         srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
 716         hp->status = 0;
 717         hp->masked_status = 0;
 718         hp->msg_status = 0;
 719         hp->info = 0;
 720         hp->host_status = 0;
 721         hp->driver_status = 0;
 722         hp->resid = 0;
 723         SCSI_LOG_TIMEOUT(4, printk("sg_common_write:  scsi opcode=0x%02x, cmd_size=%d\n",
 724                           (int) cmnd[0], (int) hp->cmd_len));
 725
 726         if ((k = sg_start_req(srp))) {
 727                 SCSI_LOG_TIMEOUT(1, printk("sg_common_write: start_req err=%d\n", k));
 728                 sg_finish_rem_req(srp);
 729                 return k;       /* probably out of space --> ENOMEM */
 730         }
 731         if ((k = sg_write_xfer(srp))) {
 732                 SCSI_LOG_TIMEOUT(1, printk("sg_common_write: write_xfer, bad address\n"));
 733                 sg_finish_rem_req(srp);
 734                 return k;
 735         }
 736         if (sdp->detached) {
 737                 sg_finish_rem_req(srp);
 738                 return -ENODEV;
 739         }
 740
 741         switch (hp->dxfer_direction) {
 742         case SG_DXFER_TO_FROM_DEV:
 743         case SG_DXFER_FROM_DEV:
 744                 data_dir = DMA_FROM_DEVICE;
 745                 break;
 746         case SG_DXFER_TO_DEV:
 747                 data_dir = DMA_TO_DEVICE;
 748                 break;
 749         case SG_DXFER_UNKNOWN:
 750                 data_dir = DMA_BIDIRECTIONAL;
 751                 break;
 752         default:
 753                 data_dir = DMA_NONE;
 754                 break;
 755         }
 756         hp->duration = jiffies_to_msecs(jiffies);
 757 /* Now send everything of to mid-level. The next time we hear about this
 758    packet is when sg_cmd_done() is called (i.e. a callback). */
 759         if (scsi_execute_async(sdp->device, cmnd, hp->cmd_len, data_dir, srp->data.buffer,
 760                                 hp->dxfer_len, srp->data.k_use_sg, timeout,
 761                                 SG_DEFAULT_RETRIES, srp, sg_cmd_done,
 762                                 GFP_ATOMIC)) {
 763                 SCSI_LOG_TIMEOUT(1, printk("sg_common_write: scsi_execute_async failed\n"));
 764                 /*
 765                  * most likely out of mem, but could also be a bad map
 766                  */
 767                 sg_finish_rem_req(srp);
 768                 return -ENOMEM;
 769         } else
 770                 return 0;
 771 }
 772
 773 static int
 774 sg_srp_done(Sg_request *srp, Sg_fd *sfp)
 775 {
 776         unsigned long iflags;
 777         int done;
 778
 779         read_lock_irqsave(&sfp->rq_list_lock, iflags);
 780         done = srp->done;
 781         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 782         return done;
 783 }
 784
 785 static int
 786 sg_ioctl(struct inode *inode, struct file *filp,
 787          unsigned int cmd_in, unsigned long arg)
 788 {
 789         void __user *p = (void __user *)arg;
 790         int __user *ip = p;
 791         int result, val, read_only;
 792         Sg_device *sdp;
 793         Sg_fd *sfp;
 794         Sg_request *srp;
 795         unsigned long iflags;
 796
 797         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 798                 return -ENXIO;
 799
 800         SCSI_LOG_TIMEOUT(3, printk("sg_ioctl: %s, cmd=0x%x\n",
 801                                    sdp->disk->disk_name, (int) cmd_in));
 802         read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
 803
 804         switch (cmd_in) {
 805         case SG_IO:
 806                 {
 807                         int blocking = 1;       /* ignore O_NONBLOCK flag */
 808
 809                         if (sdp->detached)
 810                                 return -ENODEV;
 811                         if (!scsi_block_when_processing_errors(sdp->device))
 812                                 return -ENXIO;
 813                         if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
 814                                 return -EFAULT;
 815                         result =
 816                             sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
 817                                          blocking, read_only, &srp);
 818                         if (result < 0)
 819                                 return result;
 820                         srp->sg_io_owned = 1;
 821                         while (1) {
 822                                 result = 0;     /* following macro to beat race condition */
 823                                 __wait_event_interruptible(sfp->read_wait,
 824                                         (sdp->detached || sfp->closed || sg_srp_done(srp, sfp)),
 825                                                            result);
 826                                 if (sdp->detached)
 827                                         return -ENODEV;
 828                                 if (sfp->closed)
 829                                         return 0;       /* request packet dropped already */
 830                                 if (0 == result)
 831                                         break;
 832                                 srp->orphan = 1;
 833                                 return result;  /* -ERESTARTSYS because signal hit process */
 834                         }
 835                         write_lock_irqsave(&sfp->rq_list_lock, iflags);
 836                         srp->done = 2;
 837                         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 838                         result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
 839                         return (result < 0) ? result : 0;
 840                 }
 841         case SG_SET_TIMEOUT:
 842                 result = get_user(val, ip);
 843                 if (result)
 844                         return result;
 845                 if (val < 0)
 846                         return -EIO;
 847                 if (val >= MULDIV (INT_MAX, USER_HZ, HZ))
 848                     val = MULDIV (INT_MAX, USER_HZ, HZ);
 849                 sfp->timeout_user = val;
 850                 sfp->timeout = MULDIV (val, HZ, USER_HZ);
 851
 852                 return 0;
 853         case SG_GET_TIMEOUT:    /* N.B. User receives timeout as return value */
 854                                 /* strange ..., for backward compatibility */
 855                 return sfp->timeout_user;
 856         case SG_SET_FORCE_LOW_DMA:
 857                 result = get_user(val, ip);
 858                 if (result)
 859                         return result;
 860                 if (val) {
 861                         sfp->low_dma = 1;
 862                         if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
 863                                 val = (int) sfp->reserve.bufflen;
 864                                 sg_remove_scat(&sfp->reserve);
 865                                 sg_build_reserve(sfp, val);
 866                         }
 867                 } else {
 868                         if (sdp->detached)
 869                                 return -ENODEV;
 870                         sfp->low_dma = sdp->device->host->unchecked_isa_dma;
 871                 }
 872                 return 0;
 873         case SG_GET_LOW_DMA:
 874                 return put_user((int) sfp->low_dma, ip);
 875         case SG_GET_SCSI_ID:
 876                 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
 877                         return -EFAULT;
 878                 else {
 879                         sg_scsi_id_t __user *sg_idp = p;
 880
 881                         if (sdp->detached)
 882                                 return -ENODEV;
 883                         __put_user((int) sdp->device->host->host_no,
 884                                    &sg_idp->host_no);
 885                         __put_user((int) sdp->device->channel,
 886                                    &sg_idp->channel);
 887                         __put_user((int) sdp->device->id, &sg_idp->scsi_id);
 888                         __put_user((int) sdp->device->lun, &sg_idp->lun);
 889                         __put_user((int) sdp->device->type, &sg_idp->scsi_type);
 890                         __put_user((short) sdp->device->host->cmd_per_lun,
 891                                    &sg_idp->h_cmd_per_lun);
 892                         __put_user((short) sdp->device->queue_depth,
 893                                    &sg_idp->d_queue_depth);
 894                         __put_user(0, &sg_idp->unused[0]);
 895                         __put_user(0, &sg_idp->unused[1]);
 896                         return 0;
 897                 }
 898         case SG_SET_FORCE_PACK_ID:
 899                 result = get_user(val, ip);
 900                 if (result)
 901                         return result;
 902                 sfp->force_packid = val ? 1 : 0;
 903                 return 0;
 904         case SG_GET_PACK_ID:
 905                 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
 906                         return -EFAULT;
 907                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 908                 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
 909                         if ((1 == srp->done) && (!srp->sg_io_owned)) {
 910                                 read_unlock_irqrestore(&sfp->rq_list_lock,
 911                                                        iflags);
 912                                 __put_user(srp->header.pack_id, ip);
 913                                 return 0;
 914                         }
 915                 }
 916                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 917                 __put_user(-1, ip);
 918                 return 0;
 919         case SG_GET_NUM_WAITING:
 920                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 921                 for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) {
 922                         if ((1 == srp->done) && (!srp->sg_io_owned))
 923                                 ++val;
 924                 }
 925                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 926                 return put_user(val, ip);
 927         case SG_GET_SG_TABLESIZE:
 928                 return put_user(sdp->sg_tablesize, ip);
 929         case SG_SET_RESERVED_SIZE:
 930                 result = get_user(val, ip);
 931                 if (result)
 932                         return result;
 933                 if (val < 0)
 934                         return -EINVAL;
 935                 val = min_t(int, val,
 936                                 sdp->device->request_queue->max_sectors * 512);
 937                 if (val != sfp->reserve.bufflen) {
 938                         if (sg_res_in_use(sfp) || sfp->mmap_called)
 939                                 return -EBUSY;
 940                         sg_remove_scat(&sfp->reserve);
 941                         sg_build_reserve(sfp, val);
 942                 }
 943                 return 0;
 944         case SG_GET_RESERVED_SIZE:
 945                 val = min_t(int, sfp->reserve.bufflen,
 946                                 sdp->device->request_queue->max_sectors * 512);
 947                 return put_user(val, ip);
 948         case SG_SET_COMMAND_Q:
 949                 result = get_user(val, ip);
 950                 if (result)
 951                         return result;
 952                 sfp->cmd_q = val ? 1 : 0;
 953                 return 0;
 954         case SG_GET_COMMAND_Q:
 955                 return put_user((int) sfp->cmd_q, ip);
 956         case SG_SET_KEEP_ORPHAN:
 957                 result = get_user(val, ip);
 958                 if (result)
 959                         return result;
 960                 sfp->keep_orphan = val;
 961                 return 0;
 962         case SG_GET_KEEP_ORPHAN:
 963                 return put_user((int) sfp->keep_orphan, ip);
 964         case SG_NEXT_CMD_LEN:
 965                 result = get_user(val, ip);
 966                 if (result)
 967                         return result;
 968                 sfp->next_cmd_len = (val > 0) ? val : 0;
 969                 return 0;
 970         case SG_GET_VERSION_NUM:
 971                 return put_user(sg_version_num, ip);
 972         case SG_GET_ACCESS_COUNT:
 973                 /* faked - we don't have a real access count anymore */
 974                 val = (sdp->device ? 1 : 0);
 975                 return put_user(val, ip);
 976         case SG_GET_REQUEST_TABLE:
 977                 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
 978                         return -EFAULT;
 979                 else {
 980                         sg_req_info_t *rinfo;
 981                         unsigned int ms;
 982
 983                         rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
 984                                                                 GFP_KERNEL);
 985                         if (!rinfo)
 986                                 return -ENOMEM;
 987                         read_lock_irqsave(&sfp->rq_list_lock, iflags);
 988                         for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE;
 989                              ++val, srp = srp ? srp->nextrp : srp) {
 990                                 memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
 991                                 if (srp) {
 992                                         rinfo[val].req_state = srp->done + 1;
 993                                         rinfo[val].problem =
 994                                             srp->header.masked_status &
 995                                             srp->header.host_status &
 996                                             srp->header.driver_status;
 997                                         if (srp->done)
 998                                                 rinfo[val].duration =
 999                                                         srp->header.duration;
1000                                         else {
1001                                                 ms = jiffies_to_msecs(jiffies);
1002                                                 rinfo[val].duration =
1003                                                     (ms > srp->header.duration) ?
1004                                                     (ms - srp->header.duration) : 0;
1005                                         }
1006                                         rinfo[val].orphan = srp->orphan;
1007                                         rinfo[val].sg_io_owned =
1008                                                         srp->sg_io_owned;
1009                                         rinfo[val].pack_id =
1010                                                         srp->header.pack_id;
1011                                         rinfo[val].usr_ptr =
1012                                                         srp->header.usr_ptr;
1013                                 }
1014                         }
1015                         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1016                         result = __copy_to_user(p, rinfo,
1017                                                 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1018                         result = result ? -EFAULT : 0;
1019                         kfree(rinfo);
1020                         return result;
1021                 }
1022         case SG_EMULATED_HOST:
1023                 if (sdp->detached)
1024                         return -ENODEV;
1025                 return put_user(sdp->device->host->hostt->emulated, ip);
1026         case SG_SCSI_RESET:
1027                 if (sdp->detached)
1028                         return -ENODEV;
1029                 if (filp->f_flags & O_NONBLOCK) {
1030                         if (scsi_host_in_recovery(sdp->device->host))
1031                                 return -EBUSY;
1032                 } else if (!scsi_block_when_processing_errors(sdp->device))
1033                         return -EBUSY;
1034                 result = get_user(val, ip);
1035                 if (result)
1036                         return result;
1037                 if (SG_SCSI_RESET_NOTHING == val)
1038                         return 0;
1039                 switch (val) {
1040                 case SG_SCSI_RESET_DEVICE:
1041                         val = SCSI_TRY_RESET_DEVICE;
1042                         break;
1043                 case SG_SCSI_RESET_TARGET:
1044                         val = SCSI_TRY_RESET_TARGET;
1045                         break;
1046                 case SG_SCSI_RESET_BUS:
1047                         val = SCSI_TRY_RESET_BUS;
1048                         break;
1049                 case SG_SCSI_RESET_HOST:
1050                         val = SCSI_TRY_RESET_HOST;
1051                         break;
1052                 default:
1053                         return -EINVAL;
1054                 }
1055                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1056                         return -EACCES;
1057                 return (scsi_reset_provider(sdp->device, val) ==
1058                         SUCCESS) ? 0 : -EIO;
1059         case SCSI_IOCTL_SEND_COMMAND:
1060                 if (sdp->detached)
1061                         return -ENODEV;
1062                 if (read_only) {
1063                         unsigned char opcode = WRITE_6;
1064                         struct request_queue *q = sdp->device->request_queue;
1065                         Scsi_Ioctl_Command __user *siocp = p;
1066
1067                         if (copy_from_user(&opcode, siocp->data, 1))
1068                                 return -EFAULT;
1069                         if (blk_verify_command(&q->cmd_filter,
1070                                                &opcode,
1071                                                filp->f_mode & FMODE_WRITE))
1072                                 return -EPERM;
1073                 }
1074                 return sg_scsi_ioctl(filp, sdp->device->request_queue, NULL, p);
1075         case SG_SET_DEBUG:
1076                 result = get_user(val, ip);
1077                 if (result)
1078                         return result;
1079                 sdp->sgdebug = (char) val;
1080                 return 0;
1081         case SCSI_IOCTL_GET_IDLUN:
1082         case SCSI_IOCTL_GET_BUS_NUMBER:
1083         case SCSI_IOCTL_PROBE_HOST:
1084         case SG_GET_TRANSFORM:
1085                 if (sdp->detached)
1086                         return -ENODEV;
1087                 return scsi_ioctl(sdp->device, cmd_in, p);
1088         case BLKSECTGET:
1089                 return put_user(sdp->device->request_queue->max_sectors * 512,
1090                                 ip);
1091         case BLKTRACESETUP:
1092                 return blk_trace_setup(sdp->device->request_queue,
1093                                        sdp->disk->disk_name,
1094                                        sdp->device->sdev_gendev.devt,
1095                                        (char *)arg);
1096         case BLKTRACESTART:
1097                 return blk_trace_startstop(sdp->device->request_queue, 1);
1098         case BLKTRACESTOP:
1099                 return blk_trace_startstop(sdp->device->request_queue, 0);
1100         case BLKTRACETEARDOWN:
1101                 return blk_trace_remove(sdp->device->request_queue);
1102         default:
1103                 if (read_only)
1104                         return -EPERM;  /* don't know so take safe approach */
1105                 return scsi_ioctl(sdp->device, cmd_in, p);
1106         }
1107 }
1108
1109 #ifdef CONFIG_COMPAT
1110 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1111 {
1112         Sg_device *sdp;
1113         Sg_fd *sfp;
1114         struct scsi_device *sdev;
1115
1116         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1117                 return -ENXIO;
1118
1119         sdev = sdp->device;
1120         if (sdev->host->hostt->compat_ioctl) {
1121                 int ret;
1122
1123                 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1124
1125                 return ret;
1126         }
1127
1128         return -ENOIOCTLCMD;
1129 }
1130 #endif
1131
1132 static unsigned int
1133 sg_poll(struct file *filp, poll_table * wait)
1134 {
1135         unsigned int res = 0;
1136         Sg_device *sdp;
1137         Sg_fd *sfp;
1138         Sg_request *srp;
1139         int count = 0;
1140         unsigned long iflags;
1141
1142         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))
1143             || sfp->closed)
1144                 return POLLERR;
1145         poll_wait(filp, &sfp->read_wait, wait);
1146         read_lock_irqsave(&sfp->rq_list_lock, iflags);
1147         for (srp = sfp->headrp; srp; srp = srp->nextrp) {
1148                 /* if any read waiting, flag it */
1149                 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1150                         res = POLLIN | POLLRDNORM;
1151                 ++count;
1152         }
1153         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1154
1155         if (sdp->detached)
1156                 res |= POLLHUP;
1157         else if (!sfp->cmd_q) {
1158                 if (0 == count)
1159                         res |= POLLOUT | POLLWRNORM;
1160         } else if (count < SG_MAX_QUEUE)
1161                 res |= POLLOUT | POLLWRNORM;
1162         SCSI_LOG_TIMEOUT(3, printk("sg_poll: %s, res=0x%x\n",
1163                                    sdp->disk->disk_name, (int) res));
1164         return res;
1165 }
1166
1167 static int
1168 sg_fasync(int fd, struct file *filp, int mode)
1169 {
1170         int retval;
1171         Sg_device *sdp;
1172         Sg_fd *sfp;
1173
1174         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1175                 return -ENXIO;
1176         SCSI_LOG_TIMEOUT(3, printk("sg_fasync: %s, mode=%d\n",
1177                                    sdp->disk->disk_name, mode));
1178
1179         retval = fasync_helper(fd, filp, mode, &sfp->async_qp);
1180         return (retval < 0) ? retval : 0;
1181 }
1182
1183 static int
1184 sg_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1185 {
1186         Sg_fd *sfp;
1187         unsigned long offset, len, sa;
1188         Sg_scatter_hold *rsv_schp;
1189         struct scatterlist *sg;
1190         int k;
1191
1192         if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1193                 return VM_FAULT_SIGBUS;
1194         rsv_schp = &sfp->reserve;
1195         offset = vmf->pgoff << PAGE_SHIFT;
1196         if (offset >= rsv_schp->bufflen)
1197                 return VM_FAULT_SIGBUS;
1198         SCSI_LOG_TIMEOUT(3, printk("sg_vma_fault: offset=%lu, scatg=%d\n",
1199                                    offset, rsv_schp->k_use_sg));
1200         sg = rsv_schp->buffer;
1201         sa = vma->vm_start;
1202         for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
1203              ++k, sg = sg_next(sg)) {
1204                 len = vma->vm_end - sa;
1205                 len = (len < sg->length) ? len : sg->length;
1206                 if (offset < len) {
1207                         struct page *page;
1208                         page = virt_to_page(page_address(sg_page(sg)) + offset);
1209                         get_page(page); /* increment page count */
1210                         vmf->page = page;
1211                         return 0; /* success */
1212                 }
1213                 sa += len;
1214                 offset -= len;
1215         }
1216
1217         return VM_FAULT_SIGBUS;
1218 }
1219
1220 static struct vm_operations_struct sg_mmap_vm_ops = {
1221         .fault = sg_vma_fault,
1222 };
1223
1224 static int
1225 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1226 {
1227         Sg_fd *sfp;
1228         unsigned long req_sz, len, sa;
1229         Sg_scatter_hold *rsv_schp;
1230         int k;
1231         struct scatterlist *sg;
1232
1233         if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1234                 return -ENXIO;
1235         req_sz = vma->vm_end - vma->vm_start;
1236         SCSI_LOG_TIMEOUT(3, printk("sg_mmap starting, vm_start=%p, len=%d\n",
1237                                    (void *) vma->vm_start, (int) req_sz));
1238         if (vma->vm_pgoff)
1239                 return -EINVAL; /* want no offset */
1240         rsv_schp = &sfp->reserve;
1241         if (req_sz > rsv_schp->bufflen)
1242                 return -ENOMEM; /* cannot map more than reserved buffer */
1243
1244         sa = vma->vm_start;
1245         sg = rsv_schp->buffer;
1246         for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
1247              ++k, sg = sg_next(sg)) {
1248                 len = vma->vm_end - sa;
1249                 len = (len < sg->length) ? len : sg->length;
1250                 sa += len;
1251         }
1252
1253         sfp->mmap_called = 1;
1254         vma->vm_flags |= VM_RESERVED;
1255         vma->vm_private_data = sfp;
1256         vma->vm_ops = &sg_mmap_vm_ops;
1257         return 0;
1258 }
1259
1260 /* This function is a "bottom half" handler that is called by the
1261  * mid level when a command is completed (or has failed). */
1262 static void
1263 sg_cmd_done(void *data, char *sense, int result, int resid)
1264 {
1265         Sg_request *srp = data;
1266         Sg_device *sdp = NULL;
1267         Sg_fd *sfp;
1268         unsigned long iflags;
1269         unsigned int ms;
1270
1271         if (NULL == srp) {
1272                 printk(KERN_ERR "sg_cmd_done: NULL request\n");
1273                 return;
1274         }
1275         sfp = srp->parentfp;
1276         if (sfp)
1277                 sdp = sfp->parentdp;
1278         if ((NULL == sdp) || sdp->detached) {
1279                 printk(KERN_INFO "sg_cmd_done: device detached\n");
1280                 return;
1281         }
1282
1283
1284         SCSI_LOG_TIMEOUT(4, printk("sg_cmd_done: %s, pack_id=%d, res=0x%x\n",
1285                 sdp->disk->disk_name, srp->header.pack_id, result));
1286         srp->header.resid = resid;
1287         ms = jiffies_to_msecs(jiffies);
1288         srp->header.duration = (ms > srp->header.duration) ?
1289                                 (ms - srp->header.duration) : 0;
1290         if (0 != result) {
1291                 struct scsi_sense_hdr sshdr;
1292
1293                 memcpy(srp->sense_b, sense, sizeof (srp->sense_b));
1294                 srp->header.status = 0xff & result;
1295                 srp->header.masked_status = status_byte(result);
1296                 srp->header.msg_status = msg_byte(result);
1297                 srp->header.host_status = host_byte(result);
1298                 srp->header.driver_status = driver_byte(result);
1299                 if ((sdp->sgdebug > 0) &&
1300                     ((CHECK_CONDITION == srp->header.masked_status) ||
1301                      (COMMAND_TERMINATED == srp->header.masked_status)))
1302                         __scsi_print_sense("sg_cmd_done", sense,
1303                                            SCSI_SENSE_BUFFERSIZE);
1304
1305                 /* Following if statement is a patch supplied by Eric Youngdale */
1306                 if (driver_byte(result) != 0
1307                     && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1308                     && !scsi_sense_is_deferred(&sshdr)
1309                     && sshdr.sense_key == UNIT_ATTENTION
1310                     && sdp->device->removable) {
1311                         /* Detected possible disc change. Set the bit - this */
1312                         /* may be used if there are filesystems using this device */
1313                         sdp->device->changed = 1;
1314                 }
1315         }
1316         /* Rely on write phase to clean out srp status values, so no "else" */
1317
1318         if (sfp->closed) {      /* whoops this fd already released, cleanup */
1319                 SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, freeing ...\n"));
1320                 sg_finish_rem_req(srp);
1321                 srp = NULL;
1322                 if (NULL == sfp->headrp) {
1323                         SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, final cleanup\n"));
1324                         if (0 == sg_remove_sfp(sdp, sfp)) {     /* device still present */
1325                                 scsi_device_put(sdp->device);
1326                         }
1327                         sfp = NULL;
1328                 }
1329         } else if (srp && srp->orphan) {
1330                 if (sfp->keep_orphan)
1331                         srp->sg_io_owned = 0;
1332                 else {
1333                         sg_finish_rem_req(srp);
1334                         srp = NULL;
1335                 }
1336         }
1337         if (sfp && srp) {
1338                 /* Now wake up any sg_read() that is waiting for this packet. */
1339                 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1340                 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1341                 srp->done = 1;
1342                 wake_up_interruptible(&sfp->read_wait);
1343                 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1344         }
1345 }
1346
1347 static struct file_operations sg_fops = {
1348         .owner = THIS_MODULE,
1349         .read = sg_read,
1350         .write = sg_write,
1351         .poll = sg_poll,
1352         .ioctl = sg_ioctl,
1353 #ifdef CONFIG_COMPAT
1354         .compat_ioctl = sg_compat_ioctl,
1355 #endif
1356         .open = sg_open,
1357         .mmap = sg_mmap,
1358         .release = sg_release,
1359         .fasync = sg_fasync,
1360 };
1361
1362 static struct class *sg_sysfs_class;
1363
1364 static int sg_sysfs_valid = 0;
1365
1366 static Sg_device *sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1367 {
1368         struct request_queue *q = scsidp->request_queue;
1369         Sg_device *sdp;
1370         unsigned long iflags;
1371         int error;
1372         u32 k;
1373
1374         sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1375         if (!sdp) {
1376                 printk(KERN_WARNING "kmalloc Sg_device failure\n");
1377                 return ERR_PTR(-ENOMEM);
1378         }
1379         error = -ENOMEM;
1380         if (!idr_pre_get(&sg_index_idr, GFP_KERNEL)) {
1381                 printk(KERN_WARNING "idr expansion Sg_device failure\n");
1382                 goto out;
1383         }
1384
1385         write_lock_irqsave(&sg_index_lock, iflags);
1386         error = idr_get_new(&sg_index_idr, sdp, &k);
1387         write_unlock_irqrestore(&sg_index_lock, iflags);
1388
1389         if (error) {
1390                 printk(KERN_WARNING "idr allocation Sg_device failure: %d\n",
1391                        error);
1392                 goto out;
1393         }
1394
1395         if (unlikely(k >= SG_MAX_DEVS))
1396                 goto overflow;
1397
1398         SCSI_LOG_TIMEOUT(3, printk("sg_alloc: dev=%d \n", k));
1399         sprintf(disk->disk_name, "sg%d", k);
1400         disk->first_minor = k;
1401         sdp->disk = disk;
1402         sdp->device = scsidp;
1403         init_waitqueue_head(&sdp->o_excl_wait);
1404         sdp->sg_tablesize = min(q->max_hw_segments, q->max_phys_segments);
1405         sdp->index = k;
1406
1407         error = 0;
1408  out:
1409         if (error) {
1410                 kfree(sdp);
1411                 return ERR_PTR(error);
1412         }
1413         return sdp;
1414
1415  overflow:
1416         sdev_printk(KERN_WARNING, scsidp,
1417                     "Unable to attach sg device type=%d, minor "
1418                     "number exceeds %d\n", scsidp->type, SG_MAX_DEVS - 1);
1419         error = -ENODEV;
1420         goto out;
1421 }
1422
1423 static int
1424 sg_add(struct device *cl_dev, struct class_interface *cl_intf)
1425 {
1426         struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1427         struct gendisk *disk;
1428         Sg_device *sdp = NULL;
1429         struct cdev * cdev = NULL;
1430         int error;
1431         unsigned long iflags;
1432
1433         disk = alloc_disk(1);
1434         if (!disk) {
1435                 printk(KERN_WARNING "alloc_disk failed\n");
1436                 return -ENOMEM;
1437         }
1438         disk->major = SCSI_GENERIC_MAJOR;
1439
1440         error = -ENOMEM;
1441         cdev = cdev_alloc();
1442         if (!cdev) {
1443                 printk(KERN_WARNING "cdev_alloc failed\n");
1444                 goto out;
1445         }
1446         cdev->owner = THIS_MODULE;
1447         cdev->ops = &sg_fops;
1448
1449         sdp = sg_alloc(disk, scsidp);
1450         if (IS_ERR(sdp)) {
1451                 printk(KERN_WARNING "sg_alloc failed\n");
1452                 error = PTR_ERR(sdp);
1453                 goto out;
1454         }
1455
1456         error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1457         if (error)
1458                 goto cdev_add_err;
1459
1460         sdp->cdev = cdev;
1461         if (sg_sysfs_valid) {
1462                 struct device *sg_class_member;
1463
1464                 sg_class_member = device_create_drvdata(sg_sysfs_class,
1465                                                         cl_dev->parent,
1466                                                         MKDEV(SCSI_GENERIC_MAJOR,
1467                                                               sdp->index),
1468                                                         sdp,
1469                                                         "%s", disk->disk_name);
1470                 if (IS_ERR(sg_class_member)) {
1471                         printk(KERN_ERR "sg_add: "
1472                                "device_create failed\n");
1473                         error = PTR_ERR(sg_class_member);
1474                         goto cdev_add_err;
1475                 }
1476                 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1477                                           &sg_class_member->kobj, "generic");
1478                 if (error)
1479                         printk(KERN_ERR "sg_add: unable to make symlink "
1480                                         "'generic' back to sg%d\n", sdp->index);
1481         } else
1482                 printk(KERN_WARNING "sg_add: sg_sys Invalid\n");
1483
1484         sdev_printk(KERN_NOTICE, scsidp,
1485                     "Attached scsi generic sg%d type %d\n", sdp->index,
1486                     scsidp->type);
1487
1488         dev_set_drvdata(cl_dev, sdp);
1489
1490         return 0;
1491
1492 cdev_add_err:
1493         write_lock_irqsave(&sg_index_lock, iflags);
1494         idr_remove(&sg_index_idr, sdp->index);
1495         write_unlock_irqrestore(&sg_index_lock, iflags);
1496         kfree(sdp);
1497
1498 out:
1499         put_disk(disk);
1500         if (cdev)
1501                 cdev_del(cdev);
1502         return error;
1503 }
1504
1505 static void
1506 sg_remove(struct device *cl_dev, struct class_interface *cl_intf)
1507 {
1508         struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1509         Sg_device *sdp = dev_get_drvdata(cl_dev);
1510         unsigned long iflags;
1511         Sg_fd *sfp;
1512         Sg_fd *tsfp;
1513         Sg_request *srp;
1514         Sg_request *tsrp;
1515         int delay;
1516
1517         if (!sdp)
1518                 return;
1519
1520         delay = 0;
1521         write_lock_irqsave(&sg_index_lock, iflags);
1522         if (sdp->headfp) {
1523                 sdp->detached = 1;
1524                 for (sfp = sdp->headfp; sfp; sfp = tsfp) {
1525                         tsfp = sfp->nextfp;
1526                         for (srp = sfp->headrp; srp; srp = tsrp) {
1527                                 tsrp = srp->nextrp;
1528                                 if (sfp->closed || (0 == sg_srp_done(srp, sfp)))
1529                                         sg_finish_rem_req(srp);
1530                         }
1531                         if (sfp->closed) {
1532                                 scsi_device_put(sdp->device);
1533                                 __sg_remove_sfp(sdp, sfp);
1534                         } else {
1535                                 delay = 1;
1536                                 wake_up_interruptible(&sfp->read_wait);
1537                                 kill_fasync(&sfp->async_qp, SIGPOLL,
1538                                             POLL_HUP);
1539                         }
1540                 }
1541                 SCSI_LOG_TIMEOUT(3, printk("sg_remove: dev=%d, dirty\n", sdp->index));
1542                 if (NULL == sdp->headfp) {
1543                         idr_remove(&sg_index_idr, sdp->index);
1544                 }
1545         } else {        /* nothing active, simple case */
1546                 SCSI_LOG_TIMEOUT(3, printk("sg_remove: dev=%d\n", sdp->index));
1547                 idr_remove(&sg_index_idr, sdp->index);
1548         }
1549         write_unlock_irqrestore(&sg_index_lock, iflags);
1550
1551         sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1552         device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1553         cdev_del(sdp->cdev);
1554         sdp->cdev = NULL;
1555         put_disk(sdp->disk);
1556         sdp->disk = NULL;
1557         if (NULL == sdp->headfp)
1558                 kfree(sdp);
1559
1560         if (delay)
1561                 msleep(10);     /* dirty detach so delay device destruction */
1562 }
1563
1564 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1565 module_param_named(def_reserved_size, def_reserved_size, int,
1566                    S_IRUGO | S_IWUSR);
1567 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1568
1569 MODULE_AUTHOR("Douglas Gilbert");
1570 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1571 MODULE_LICENSE("GPL");
1572 MODULE_VERSION(SG_VERSION_STR);
1573 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1574
1575 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1576                 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1577 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1578 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1579
1580 static int __init
1581 init_sg(void)
1582 {
1583         int rc;
1584
1585         if (scatter_elem_sz < PAGE_SIZE) {
1586                 scatter_elem_sz = PAGE_SIZE;
1587                 scatter_elem_sz_prev = scatter_elem_sz;
1588         }
1589         if (def_reserved_size >= 0)
1590                 sg_big_buff = def_reserved_size;
1591         else
1592                 def_reserved_size = sg_big_buff;
1593
1594         rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1595                                     SG_MAX_DEVS, "sg");
1596         if (rc)
1597                 return rc;
1598         sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1599         if ( IS_ERR(sg_sysfs_class) ) {
1600                 rc = PTR_ERR(sg_sysfs_class);
1601                 goto err_out;
1602         }
1603         sg_sysfs_valid = 1;
1604         rc = scsi_register_interface(&sg_interface);
1605         if (0 == rc) {
1606 #ifdef CONFIG_SCSI_PROC_FS
1607                 sg_proc_init();
1608 #endif                          /* CONFIG_SCSI_PROC_FS */
1609                 return 0;
1610         }
1611         class_destroy(sg_sysfs_class);
1612 err_out:
1613         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1614         return rc;
1615 }
1616
1617 static void __exit
1618 exit_sg(void)
1619 {
1620 #ifdef CONFIG_SCSI_PROC_FS
1621         sg_proc_cleanup();
1622 #endif                          /* CONFIG_SCSI_PROC_FS */
1623         scsi_unregister_interface(&sg_interface);
1624         class_destroy(sg_sysfs_class);
1625         sg_sysfs_valid = 0;
1626         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1627                                  SG_MAX_DEVS);
1628         idr_destroy(&sg_index_idr);
1629 }
1630
1631 static int
1632 sg_start_req(Sg_request * srp)
1633 {
1634         int res;
1635         Sg_fd *sfp = srp->parentfp;
1636         sg_io_hdr_t *hp = &srp->header;
1637         int dxfer_len = (int) hp->dxfer_len;
1638         int dxfer_dir = hp->dxfer_direction;
1639         Sg_scatter_hold *req_schp = &srp->data;
1640         Sg_scatter_hold *rsv_schp = &sfp->reserve;
1641
1642         SCSI_LOG_TIMEOUT(4, printk("sg_start_req: dxfer_len=%d\n", dxfer_len));
1643         if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1644                 return 0;
1645         if (sg_allow_dio && (hp->flags & SG_FLAG_DIRECT_IO) &&
1646             (dxfer_dir != SG_DXFER_UNKNOWN) && (0 == hp->iovec_count) &&
1647             (!sfp->parentdp->device->host->unchecked_isa_dma)) {
1648                 res = sg_build_direct(srp, sfp, dxfer_len);
1649                 if (res <= 0)   /* -ve -> error, 0 -> done, 1 -> try indirect */
1650                         return res;
1651         }
1652         if ((!sg_res_in_use(sfp)) && (dxfer_len <= rsv_schp->bufflen))
1653                 sg_link_reserve(sfp, srp, dxfer_len);
1654         else {
1655                 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1656                 if (res) {
1657                         sg_remove_scat(req_schp);
1658                         return res;
1659                 }
1660         }
1661         return 0;
1662 }
1663
1664 static void
1665 sg_finish_rem_req(Sg_request * srp)
1666 {
1667         Sg_fd *sfp = srp->parentfp;
1668         Sg_scatter_hold *req_schp = &srp->data;
1669
1670         SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n", (int) srp->res_used));
1671         if (srp->res_used)
1672                 sg_unlink_reserve(sfp, srp);
1673         else
1674                 sg_remove_scat(req_schp);
1675         sg_remove_request(sfp, srp);
1676 }
1677
1678 static int
1679 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1680 {
1681         int sg_bufflen = tablesize * sizeof(struct scatterlist);
1682         gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1683
1684         /*
1685          * TODO: test without low_dma, we should not need it since
1686          * the block layer will bounce the buffer for us
1687          *
1688          * XXX(hch): we shouldn't need GFP_DMA for the actual S/G list.
1689          */
1690         if (sfp->low_dma)
1691                  gfp_flags |= GFP_DMA;
1692         schp->buffer = kzalloc(sg_bufflen, gfp_flags);
1693         if (!schp->buffer)
1694                 return -ENOMEM;
1695         sg_init_table(schp->buffer, tablesize);
1696         schp->sglist_len = sg_bufflen;
1697         return tablesize;       /* number of scat_gath elements allocated */
1698 }
1699
1700 #ifdef SG_ALLOW_DIO_CODE
1701 /* vvvvvvvv  following code borrowed from st driver's direct IO vvvvvvvvv */
1702         /* TODO: hopefully we can use the generic block layer code */
1703
1704 /* Pin down user pages and put them into a scatter gather list. Returns <= 0 if
1705    - mapping of all pages not successful
1706    (i.e., either completely successful or fails)
1707 */
1708 static int
1709 st_map_user_pages(struct scatterlist *sgl, const unsigned int max_pages,
1710                   unsigned long uaddr, size_t count, int rw)
1711 {
1712         unsigned long end = (uaddr + count + PAGE_SIZE - 1) >> PAGE_SHIFT;
1713         unsigned long start = uaddr >> PAGE_SHIFT;
1714         const int nr_pages = end - start;
1715         int res, i, j;
1716         struct page **pages;
1717
1718         /* User attempted Overflow! */
1719         if ((uaddr + count) < uaddr)
1720                 return -EINVAL;
1721
1722         /* Too big */
1723         if (nr_pages > max_pages)
1724                 return -ENOMEM;
1725
1726         /* Hmm? */
1727         if (count == 0)
1728                 return 0;
1729
1730         if ((pages = kmalloc(max_pages * sizeof(*pages), GFP_ATOMIC)) == NULL)
1731                 return -ENOMEM;
1732
1733         /* Try to fault in all of the necessary pages */
1734         down_read(&current->mm->mmap_sem);
1735         /* rw==READ means read from drive, write into memory area */
1736         res = get_user_pages(
1737                 current,
1738                 current->mm,
1739                 uaddr,
1740                 nr_pages,
1741                 rw == READ,
1742                 0, /* don't force */
1743                 pages,
1744                 NULL);
1745         up_read(&current->mm->mmap_sem);
1746
1747         /* Errors and no page mapped should return here */
1748         if (res < nr_pages)
1749                 goto out_unmap;
1750
1751         for (i=0; i < nr_pages; i++) {
1752                 /* FIXME: flush superflous for rw==READ,
1753                  * probably wrong function for rw==WRITE
1754                  */
1755                 flush_dcache_page(pages[i]);
1756                 /* ?? Is locking needed? I don't think so */
1757                 /* if (!trylock_page(pages[i]))
1758                    goto out_unlock; */
1759         }
1760
1761         sg_set_page(sgl, pages[0], 0, uaddr & ~PAGE_MASK);
1762         if (nr_pages > 1) {
1763                 sgl[0].length = PAGE_SIZE - sgl[0].offset;
1764                 count -= sgl[0].length;
1765                 for (i=1; i < nr_pages ; i++)
1766                         sg_set_page(&sgl[i], pages[i], count < PAGE_SIZE ? count : PAGE_SIZE, 0);
1767         }
1768         else {
1769                 sgl[0].length = count;
1770         }
1771
1772         kfree(pages);
1773         return nr_pages;
1774
1775  out_unmap:
1776         if (res > 0) {
1777                 for (j=0; j < res; j++)
1778                         page_cache_release(pages[j]);
1779                 res = 0;
1780         }
1781         kfree(pages);
1782         return res;
1783 }
1784
1785
1786 /* And unmap them... */
1787 static int
1788 st_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_pages,
1789                     int dirtied)
1790 {
1791         int i;
1792
1793         for (i=0; i < nr_pages; i++) {
1794                 struct page *page = sg_page(&sgl[i]);
1795
1796                 if (dirtied)
1797                         SetPageDirty(page);
1798                 /* unlock_page(page); */
1799                 /* FIXME: cache flush missing for rw==READ
1800                  * FIXME: call the correct reference counting function
1801                  */
1802                 page_cache_release(page);
1803         }
1804
1805         return 0;
1806 }
1807
1808 /* ^^^^^^^^  above code borrowed from st driver's direct IO ^^^^^^^^^ */
1809 #endif
1810
1811
1812 /* Returns: -ve -> error, 0 -> done, 1 -> try indirect */
1813 static int
1814 sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len)
1815 {
1816 #ifdef SG_ALLOW_DIO_CODE
1817         sg_io_hdr_t *hp = &srp->header;
1818         Sg_scatter_hold *schp = &srp->data;
1819         int sg_tablesize = sfp->parentdp->sg_tablesize;
1820         int mx_sc_elems, res;
1821         struct scsi_device *sdev = sfp->parentdp->device;
1822
1823         if (((unsigned long)hp->dxferp &
1824                         queue_dma_alignment(sdev->request_queue)) != 0)
1825                 return 1;
1826
1827         mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1828         if (mx_sc_elems <= 0) {
1829                 return 1;
1830         }
1831         res = st_map_user_pages(schp->buffer, mx_sc_elems,
1832                                 (unsigned long)hp->dxferp, dxfer_len,
1833                                 (SG_DXFER_TO_DEV == hp->dxfer_direction) ? 1 : 0);
1834         if (res <= 0) {
1835                 sg_remove_scat(schp);
1836                 return 1;
1837         }
1838         schp->k_use_sg = res;
1839         schp->dio_in_use = 1;
1840         hp->info |= SG_INFO_DIRECT_IO;
1841         return 0;
1842 #else
1843         return 1;
1844 #endif
1845 }
1846
1847 static int
1848 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1849 {
1850         struct scatterlist *sg;
1851         int ret_sz = 0, k, rem_sz, num, mx_sc_elems;
1852         int sg_tablesize = sfp->parentdp->sg_tablesize;
1853         int blk_size = buff_size;
1854         struct page *p = NULL;
1855
1856         if (blk_size < 0)
1857                 return -EFAULT;
1858         if (0 == blk_size)
1859                 ++blk_size;     /* don't know why */
1860 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1861         blk_size = (blk_size + SG_SECTOR_MSK) & (~SG_SECTOR_MSK);
1862         SCSI_LOG_TIMEOUT(4, printk("sg_build_indirect: buff_size=%d, blk_size=%d\n",
1863                                    buff_size, blk_size));
1864
1865         /* N.B. ret_sz carried into this block ... */
1866         mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1867         if (mx_sc_elems < 0)
1868                 return mx_sc_elems;     /* most likely -ENOMEM */
1869
1870         num = scatter_elem_sz;
1871         if (unlikely(num != scatter_elem_sz_prev)) {
1872                 if (num < PAGE_SIZE) {
1873                         scatter_elem_sz = PAGE_SIZE;
1874                         scatter_elem_sz_prev = PAGE_SIZE;
1875                 } else
1876                         scatter_elem_sz_prev = num;
1877         }
1878         for (k = 0, sg = schp->buffer, rem_sz = blk_size;
1879              (rem_sz > 0) && (k < mx_sc_elems);
1880              ++k, rem_sz -= ret_sz, sg = sg_next(sg)) {
1881
1882                 num = (rem_sz > scatter_elem_sz_prev) ?
1883                       scatter_elem_sz_prev : rem_sz;
1884                 p = sg_page_malloc(num, sfp->low_dma, &ret_sz);
1885                 if (!p)
1886                         return -ENOMEM;
1887
1888                 if (num == scatter_elem_sz_prev) {
1889                         if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1890                                 scatter_elem_sz = ret_sz;
1891                                 scatter_elem_sz_prev = ret_sz;
1892                         }
1893                 }
1894                 sg_set_page(sg, p, (ret_sz > num) ? num : ret_sz, 0);
1895
1896                 SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k=%d, num=%d, "
1897                                  "ret_sz=%d\n", k, num, ret_sz));
1898         }               /* end of for loop */
1899
1900         schp->k_use_sg = k;
1901         SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, "
1902                          "rem_sz=%d\n", k, rem_sz));
1903
1904         schp->bufflen = blk_size;
1905         if (rem_sz > 0) /* must have failed */
1906                 return -ENOMEM;
1907
1908         return 0;
1909 }
1910
1911 static int
1912 sg_write_xfer(Sg_request * srp)
1913 {
1914         sg_io_hdr_t *hp = &srp->header;
1915         Sg_scatter_hold *schp = &srp->data;
1916         struct scatterlist *sg = schp->buffer;
1917         int num_xfer = 0;
1918         int j, k, onum, usglen, ksglen, res;
1919         int iovec_count = (int) hp->iovec_count;
1920         int dxfer_dir = hp->dxfer_direction;
1921         unsigned char *p;
1922         unsigned char __user *up;
1923         int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
1924
1925         if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_TO_DEV == dxfer_dir) ||
1926             (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
1927                 num_xfer = (int) (new_interface ? hp->dxfer_len : hp->flags);
1928                 if (schp->bufflen < num_xfer)
1929                         num_xfer = schp->bufflen;
1930         }
1931         if ((num_xfer <= 0) || (schp->dio_in_use) ||
1932             (new_interface
1933              && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
1934                 return 0;
1935
1936         SCSI_LOG_TIMEOUT(4, printk("sg_write_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
1937                           num_xfer, iovec_count, schp->k_use_sg));
1938         if (iovec_count) {
1939                 onum = iovec_count;
1940                 if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum))
1941                         return -EFAULT;
1942         } else
1943                 onum = 1;
1944
1945         ksglen = sg->length;
1946         p = page_address(sg_page(sg));
1947         for (j = 0, k = 0; j < onum; ++j) {
1948                 res = sg_u_iovec(hp, iovec_count, j, 1, &usglen, &up);
1949                 if (res)
1950                         return res;
1951
1952                 for (; p; sg = sg_next(sg), ksglen = sg->length,
1953                      p = page_address(sg_page(sg))) {
1954                         if (usglen <= 0)
1955                                 break;
1956                         if (ksglen > usglen) {
1957                                 if (usglen >= num_xfer) {
1958                                         if (__copy_from_user(p, up, num_xfer))
1959                                                 return -EFAULT;
1960                                         return 0;
1961                                 }
1962                                 if (__copy_from_user(p, up, usglen))
1963                                         return -EFAULT;
1964                                 p += usglen;
1965                                 ksglen -= usglen;
1966                                 break;
1967                         } else {
1968                                 if (ksglen >= num_xfer) {
1969                                         if (__copy_from_user(p, up, num_xfer))
1970                                                 return -EFAULT;
1971                                         return 0;
1972                                 }
1973                                 if (__copy_from_user(p, up, ksglen))
1974                                         return -EFAULT;
1975                                 up += ksglen;
1976                                 usglen -= ksglen;
1977                         }
1978                         ++k;
1979                         if (k >= schp->k_use_sg)
1980                                 return 0;
1981                 }
1982         }
1983
1984         return 0;
1985 }
1986
1987 static int
1988 sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
1989            int wr_xf, int *countp, unsigned char __user **up)
1990 {
1991         int num_xfer = (int) hp->dxfer_len;
1992         unsigned char __user *p = hp->dxferp;
1993         int count;
1994
1995         if (0 == sg_num) {
1996                 if (wr_xf && ('\0' == hp->interface_id))
1997                         count = (int) hp->flags;        /* holds "old" input_size */
1998                 else
1999                         count = num_xfer;
2000         } else {
2001                 sg_iovec_t iovec;
2002                 if (__copy_from_user(&iovec, p + ind*SZ_SG_IOVEC, SZ_SG_IOVEC))
2003                         return -EFAULT;
2004                 p = iovec.iov_base;
2005                 count = (int) iovec.iov_len;
2006         }
2007         if (!access_ok(wr_xf ? VERIFY_READ : VERIFY_WRITE, p, count))
2008                 return -EFAULT;
2009         if (up)
2010                 *up = p;
2011         if (countp)
2012                 *countp = count;
2013         return 0;
2014 }
2015
2016 static void
2017 sg_remove_scat(Sg_scatter_hold * schp)
2018 {
2019         SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
2020         if (schp->buffer && (schp->sglist_len > 0)) {
2021                 struct scatterlist *sg = schp->buffer;
2022
2023                 if (schp->dio_in_use) {
2024 #ifdef SG_ALLOW_DIO_CODE
2025                         st_unmap_user_pages(sg, schp->k_use_sg, TRUE);
2026 #endif
2027                 } else {
2028                         int k;
2029
2030                         for (k = 0; (k < schp->k_use_sg) && sg_page(sg);
2031                              ++k, sg = sg_next(sg)) {
2032                                 SCSI_LOG_TIMEOUT(5, printk(
2033                                     "sg_remove_scat: k=%d, pg=0x%p, len=%d\n",
2034                                     k, sg_page(sg), sg->length));
2035                                 sg_page_free(sg_page(sg), sg->length);
2036                         }
2037                 }
2038                 kfree(schp->buffer);
2039         }
2040         memset(schp, 0, sizeof (*schp));
2041 }
2042
2043 static int
2044 sg_read_xfer(Sg_request * srp)
2045 {
2046         sg_io_hdr_t *hp = &srp->header;
2047         Sg_scatter_hold *schp = &srp->data;
2048         struct scatterlist *sg = schp->buffer;
2049         int num_xfer = 0;
2050         int j, k, onum, usglen, ksglen, res;
2051         int iovec_count = (int) hp->iovec_count;
2052         int dxfer_dir = hp->dxfer_direction;
2053         unsigned char *p;
2054         unsigned char __user *up;
2055         int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
2056
2057         if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_FROM_DEV == dxfer_dir)
2058             || (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
2059                 num_xfer = hp->dxfer_len;
2060                 if (schp->bufflen < num_xfer)
2061                         num_xfer = schp->bufflen;
2062         }
2063         if ((num_xfer <= 0) || (schp->dio_in_use) ||
2064             (new_interface
2065              && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
2066                 return 0;
2067
2068         SCSI_LOG_TIMEOUT(4, printk("sg_read_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
2069                           num_xfer, iovec_count, schp->k_use_sg));
2070         if (iovec_count) {
2071                 onum = iovec_count;
2072                 if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum))
2073                         return -EFAULT;
2074         } else
2075                 onum = 1;
2076
2077         p = page_address(sg_page(sg));
2078         ksglen = sg->length;
2079         for (j = 0, k = 0; j < onum; ++j) {
2080                 res = sg_u_iovec(hp, iovec_count, j, 0, &usglen, &up);
2081                 if (res)
2082                         return res;
2083
2084                 for (; p; sg = sg_next(sg), ksglen = sg->length,
2085                      p = page_address(sg_page(sg))) {
2086                         if (usglen <= 0)
2087                                 break;
2088                         if (ksglen > usglen) {
2089                                 if (usglen >= num_xfer) {
2090                                         if (__copy_to_user(up, p, num_xfer))
2091                                                 return -EFAULT;
2092                                         return 0;
2093                                 }
2094                                 if (__copy_to_user(up, p, usglen))
2095                                         return -EFAULT;
2096                                 p += usglen;
2097                                 ksglen -= usglen;
2098                                 break;
2099                         } else {
2100                                 if (ksglen >= num_xfer) {
2101                                         if (__copy_to_user(up, p, num_xfer))
2102                                                 return -EFAULT;
2103                                         return 0;
2104                                 }
2105                                 if (__copy_to_user(up, p, ksglen))
2106                                         return -EFAULT;
2107                                 up += ksglen;
2108                                 usglen -= ksglen;
2109                         }
2110                         ++k;
2111                         if (k >= schp->k_use_sg)
2112                                 return 0;
2113                 }
2114         }
2115
2116         return 0;
2117 }
2118
2119 static int
2120 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
2121 {
2122         Sg_scatter_hold *schp = &srp->data;
2123         struct scatterlist *sg = schp->buffer;
2124         int k, num;
2125
2126         SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n",
2127                                    num_read_xfer));
2128         if ((!outp) || (num_read_xfer <= 0))
2129                 return 0;
2130
2131         for (k = 0; (k < schp->k_use_sg) && sg_page(sg); ++k, sg = sg_next(sg)) {
2132                 num = sg->length;
2133                 if (num > num_read_xfer) {
2134                         if (__copy_to_user(outp, page_address(sg_page(sg)),
2135                                            num_read_xfer))
2136                                 return -EFAULT;
2137                         break;
2138                 } else {
2139                         if (__copy_to_user(outp, page_address(sg_page(sg)),
2140                                            num))
2141                                 return -EFAULT;
2142                         num_read_xfer -= num;
2143                         if (num_read_xfer <= 0)
2144                                 break;
2145                         outp += num;
2146                 }
2147         }
2148
2149         return 0;
2150 }
2151
2152 static void
2153 sg_build_reserve(Sg_fd * sfp, int req_size)
2154 {
2155         Sg_scatter_hold *schp = &sfp->reserve;
2156
2157         SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
2158         do {
2159                 if (req_size < PAGE_SIZE)
2160                         req_size = PAGE_SIZE;
2161                 if (0 == sg_build_indirect(schp, sfp, req_size))
2162                         return;
2163                 else
2164                         sg_remove_scat(schp);
2165                 req_size >>= 1; /* divide by 2 */
2166         } while (req_size > (PAGE_SIZE / 2));
2167 }
2168
2169 static void
2170 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2171 {
2172         Sg_scatter_hold *req_schp = &srp->data;
2173         Sg_scatter_hold *rsv_schp = &sfp->reserve;
2174         struct scatterlist *sg = rsv_schp->buffer;
2175         int k, num, rem;
2176
2177         srp->res_used = 1;
2178         SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
2179         rem = size;
2180
2181         for (k = 0; k < rsv_schp->k_use_sg; ++k, sg = sg_next(sg)) {
2182                 num = sg->length;
2183                 if (rem <= num) {
2184                         sfp->save_scat_len = num;
2185                         sg->length = rem;
2186                         req_schp->k_use_sg = k + 1;
2187                         req_schp->sglist_len = rsv_schp->sglist_len;
2188                         req_schp->buffer = rsv_schp->buffer;
2189
2190                         req_schp->bufflen = size;
2191                         req_schp->b_malloc_len = rsv_schp->b_malloc_len;
2192                         break;
2193                 } else
2194                         rem -= num;
2195         }
2196
2197         if (k >= rsv_schp->k_use_sg)
2198                 SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
2199 }
2200
2201 static void
2202 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2203 {
2204         Sg_scatter_hold *req_schp = &srp->data;
2205         Sg_scatter_hold *rsv_schp = &sfp->reserve;
2206
2207         SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->k_use_sg=%d\n",
2208                                    (int) req_schp->k_use_sg));
2209         if ((rsv_schp->k_use_sg > 0) && (req_schp->k_use_sg > 0)) {
2210                 struct scatterlist *sg = rsv_schp->buffer;
2211
2212                 if (sfp->save_scat_len > 0)
2213                         (sg + (req_schp->k_use_sg - 1))->length =
2214                             (unsigned) sfp->save_scat_len;
2215                 else
2216                         SCSI_LOG_TIMEOUT(1, printk ("sg_unlink_reserve: BAD save_scat_len\n"));
2217         }
2218         req_schp->k_use_sg = 0;
2219         req_schp->bufflen = 0;
2220         req_schp->buffer = NULL;
2221         req_schp->sglist_len = 0;
2222         sfp->save_scat_len = 0;
2223         srp->res_used = 0;
2224 }
2225
2226 static Sg_request *
2227 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2228 {
2229         Sg_request *resp;
2230         unsigned long iflags;
2231
2232         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2233         for (resp = sfp->headrp; resp; resp = resp->nextrp) {
2234                 /* look for requests that are ready + not SG_IO owned */
2235                 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2236                     ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2237                         resp->done = 2; /* guard against other readers */
2238                         break;
2239                 }
2240         }
2241         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2242         return resp;
2243 }
2244
2245 #ifdef CONFIG_SCSI_PROC_FS
2246 static Sg_request *
2247 sg_get_nth_request(Sg_fd * sfp, int nth)
2248 {
2249         Sg_request *resp;
2250         unsigned long iflags;
2251         int k;
2252
2253         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2254         for (k = 0, resp = sfp->headrp; resp && (k < nth);
2255              ++k, resp = resp->nextrp) ;
2256         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2257         return resp;
2258 }
2259 #endif
2260
2261 /* always adds to end of list */
2262 static Sg_request *
2263 sg_add_request(Sg_fd * sfp)
2264 {
2265         int k;
2266         unsigned long iflags;
2267         Sg_request *resp;
2268         Sg_request *rp = sfp->req_arr;
2269
2270         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2271         resp = sfp->headrp;
2272         if (!resp) {
2273                 memset(rp, 0, sizeof (Sg_request));
2274                 rp->parentfp = sfp;
2275                 resp = rp;
2276                 sfp->headrp = resp;
2277         } else {
2278                 if (0 == sfp->cmd_q)
2279                         resp = NULL;    /* command queuing disallowed */
2280                 else {
2281                         for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2282                                 if (!rp->parentfp)
2283                                         break;
2284                         }
2285                         if (k < SG_MAX_QUEUE) {
2286                                 memset(rp, 0, sizeof (Sg_request));
2287                                 rp->parentfp = sfp;
2288                                 while (resp->nextrp)
2289                                         resp = resp->nextrp;
2290                                 resp->nextrp = rp;
2291                                 resp = rp;
2292                         } else
2293                                 resp = NULL;
2294                 }
2295         }
2296         if (resp) {
2297                 resp->nextrp = NULL;
2298                 resp->header.duration = jiffies_to_msecs(jiffies);
2299         }
2300         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2301         return resp;
2302 }
2303
2304 /* Return of 1 for found; 0 for not found */
2305 static int
2306 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2307 {
2308         Sg_request *prev_rp;
2309         Sg_request *rp;
2310         unsigned long iflags;
2311         int res = 0;
2312
2313         if ((!sfp) || (!srp) || (!sfp->headrp))
2314                 return res;
2315         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2316         prev_rp = sfp->headrp;
2317         if (srp == prev_rp) {
2318                 sfp->headrp = prev_rp->nextrp;
2319                 prev_rp->parentfp = NULL;
2320                 res = 1;
2321         } else {
2322                 while ((rp = prev_rp->nextrp)) {
2323                         if (srp == rp) {
2324                                 prev_rp->nextrp = rp->nextrp;
2325                                 rp->parentfp = NULL;
2326                                 res = 1;
2327                                 break;
2328                         }
2329                         prev_rp = rp;
2330                 }
2331         }
2332         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2333         return res;
2334 }
2335
2336 #ifdef CONFIG_SCSI_PROC_FS
2337 static Sg_fd *
2338 sg_get_nth_sfp(Sg_device * sdp, int nth)
2339 {
2340         Sg_fd *resp;
2341         unsigned long iflags;
2342         int k;
2343
2344         read_lock_irqsave(&sg_index_lock, iflags);
2345         for (k = 0, resp = sdp->headfp; resp && (k < nth);
2346              ++k, resp = resp->nextfp) ;
2347         read_unlock_irqrestore(&sg_index_lock, iflags);
2348         return resp;
2349 }
2350 #endif
2351
2352 static Sg_fd *
2353 sg_add_sfp(Sg_device * sdp, int dev)
2354 {
2355         Sg_fd *sfp;
2356         unsigned long iflags;
2357         int bufflen;
2358
2359         sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2360         if (!sfp)
2361                 return NULL;
2362
2363         init_waitqueue_head(&sfp->read_wait);
2364         rwlock_init(&sfp->rq_list_lock);
2365
2366         sfp->timeout = SG_DEFAULT_TIMEOUT;
2367         sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2368         sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2369         sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
2370             sdp->device->host->unchecked_isa_dma : 1;
2371         sfp->cmd_q = SG_DEF_COMMAND_Q;
2372         sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2373         sfp->parentdp = sdp;
2374         write_lock_irqsave(&sg_index_lock, iflags);
2375         if (!sdp->headfp)
2376                 sdp->headfp = sfp;
2377         else {                  /* add to tail of existing list */
2378                 Sg_fd *pfp = sdp->headfp;
2379                 while (pfp->nextfp)
2380                         pfp = pfp->nextfp;
2381                 pfp->nextfp = sfp;
2382         }
2383         write_unlock_irqrestore(&sg_index_lock, iflags);
2384         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));
2385         if (unlikely(sg_big_buff != def_reserved_size))
2386                 sg_big_buff = def_reserved_size;
2387
2388         bufflen = min_t(int, sg_big_buff,
2389                         sdp->device->request_queue->max_sectors * 512);
2390         sg_build_reserve(sfp, bufflen);
2391         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp:   bufflen=%d, k_use_sg=%d\n",
2392                            sfp->reserve.bufflen, sfp->reserve.k_use_sg));
2393         return sfp;
2394 }
2395
2396 static void
2397 __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2398 {
2399         Sg_fd *fp;
2400         Sg_fd *prev_fp;
2401
2402         prev_fp = sdp->headfp;
2403         if (sfp == prev_fp)
2404                 sdp->headfp = prev_fp->nextfp;
2405         else {
2406                 while ((fp = prev_fp->nextfp)) {
2407                         if (sfp == fp) {
2408                                 prev_fp->nextfp = fp->nextfp;
2409                                 break;
2410                         }
2411                         prev_fp = fp;
2412                 }
2413         }
2414         if (sfp->reserve.bufflen > 0) {
2415                 SCSI_LOG_TIMEOUT(6,
2416                         printk("__sg_remove_sfp:    bufflen=%d, k_use_sg=%d\n",
2417                         (int) sfp->reserve.bufflen, (int) sfp->reserve.k_use_sg));
2418                 sg_remove_scat(&sfp->reserve);
2419         }
2420         sfp->parentdp = NULL;
2421         SCSI_LOG_TIMEOUT(6, printk("__sg_remove_sfp:    sfp=0x%p\n", sfp));
2422         kfree(sfp);
2423 }
2424
2425 /* Returns 0 in normal case, 1 when detached and sdp object removed */
2426 static int
2427 sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2428 {
2429         Sg_request *srp;
2430         Sg_request *tsrp;
2431         int dirty = 0;
2432         int res = 0;
2433
2434         for (srp = sfp->headrp; srp; srp = tsrp) {
2435                 tsrp = srp->nextrp;
2436                 if (sg_srp_done(srp, sfp))
2437                         sg_finish_rem_req(srp);
2438                 else
2439                         ++dirty;
2440         }
2441         if (0 == dirty) {
2442                 unsigned long iflags;
2443
2444                 write_lock_irqsave(&sg_index_lock, iflags);
2445                 __sg_remove_sfp(sdp, sfp);
2446                 if (sdp->detached && (NULL == sdp->headfp)) {
2447                         idr_remove(&sg_index_idr, sdp->index);
2448                         kfree(sdp);
2449                         res = 1;
2450                 }
2451                 write_unlock_irqrestore(&sg_index_lock, iflags);
2452         } else {
2453                 /* MOD_INC's to inhibit unloading sg and associated adapter driver */
2454                 /* only bump the access_count if we actually succeeded in
2455                  * throwing another counter on the host module */
2456                 scsi_device_get(sdp->device);   /* XXX: retval ignored? */
2457                 sfp->closed = 1;        /* flag dirty state on this fd */
2458                 SCSI_LOG_TIMEOUT(1, printk("sg_remove_sfp: worrisome, %d writes pending\n",
2459                                   dirty));
2460         }
2461         return res;
2462 }
2463
2464 static int
2465 sg_res_in_use(Sg_fd * sfp)
2466 {
2467         const Sg_request *srp;
2468         unsigned long iflags;
2469
2470         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2471         for (srp = sfp->headrp; srp; srp = srp->nextrp)
2472                 if (srp->res_used)
2473                         break;
2474         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2475         return srp ? 1 : 0;
2476 }
2477
2478 /* The size fetched (value output via retSzp) set when non-NULL return */
2479 static struct page *
2480 sg_page_malloc(int rqSz, int lowDma, int *retSzp)
2481 {
2482         struct page *resp = NULL;
2483         gfp_t page_mask;
2484         int order, a_size;
2485         int resSz;
2486
2487         if ((rqSz <= 0) || (NULL == retSzp))
2488                 return resp;
2489
2490         if (lowDma)
2491                 page_mask = GFP_ATOMIC | GFP_DMA | __GFP_COMP | __GFP_NOWARN;
2492         else
2493                 page_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
2494
2495         for (order = 0, a_size = PAGE_SIZE; a_size < rqSz;
2496              order++, a_size <<= 1) ;
2497         resSz = a_size;         /* rounded up if necessary */
2498         resp = alloc_pages(page_mask, order);
2499         while ((!resp) && order) {
2500                 --order;
2501                 a_size >>= 1;   /* divide by 2, until PAGE_SIZE */
2502                 resp =  alloc_pages(page_mask, order);  /* try half */
2503                 resSz = a_size;
2504         }
2505         if (resp) {
2506                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2507                         memset(page_address(resp), 0, resSz);
2508                 *retSzp = resSz;
2509         }
2510         return resp;
2511 }
2512
2513 static void
2514 sg_page_free(struct page *page, int size)
2515 {
2516         int order, a_size;
2517
2518         if (!page)
2519                 return;
2520         for (order = 0, a_size = PAGE_SIZE; a_size < size;
2521              order++, a_size <<= 1) ;
2522         __free_pages(page, order);
2523 }
2524
2525 #ifdef CONFIG_SCSI_PROC_FS
2526 static int
2527 sg_idr_max_id(int id, void *p, void *data)
2528 {
2529         int *k = data;
2530
2531         if (*k < id)
2532                 *k = id;
2533
2534         return 0;
2535 }
2536
2537 static int
2538 sg_last_dev(void)
2539 {
2540         int k = -1;
2541         unsigned long iflags;
2542
2543         read_lock_irqsave(&sg_index_lock, iflags);
2544         idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2545         read_unlock_irqrestore(&sg_index_lock, iflags);
2546         return k + 1;           /* origin 1 */
2547 }
2548 #endif
2549
2550 static Sg_device *
2551 sg_get_dev(int dev)
2552 {
2553         Sg_device *sdp;
2554         unsigned long iflags;
2555
2556         read_lock_irqsave(&sg_index_lock, iflags);
2557         sdp = idr_find(&sg_index_idr, dev);
2558         read_unlock_irqrestore(&sg_index_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 = ARRAY_SIZE(sg_proc_leaf_arr);
2667         struct sg_proc_leaf * leaf;
2668
2669         sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2670         if (!sg_proc_sgp)
2671                 return 1;
2672         for (k = 0; k < num_leaves; ++k) {
2673                 leaf = &sg_proc_leaf_arr[k];
2674                 mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2675                 leaf->fops->owner = THIS_MODULE;
2676                 leaf->fops->read = seq_read;
2677                 leaf->fops->llseek = seq_lseek;
2678                 proc_create(leaf->name, mask, sg_proc_sgp, leaf->fops);
2679         }
2680         return 0;
2681 }
2682
2683 static void
2684 sg_proc_cleanup(void)
2685 {
2686         int k;
2687         int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2688
2689         if (!sg_proc_sgp)
2690                 return;
2691         for (k = 0; k < num_leaves; ++k)
2692                 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2693         remove_proc_entry(sg_proc_sg_dirname, NULL);
2694 }
2695
2696
2697 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2698 {
2699         seq_printf(s, "%d\n", *((int *)s->private));
2700         return 0;
2701 }
2702
2703 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2704 {
2705         return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2706 }
2707
2708 static ssize_t
2709 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2710                    size_t count, loff_t *off)
2711 {
2712         int num;
2713         char buff[11];
2714
2715         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2716                 return -EACCES;
2717         num = (count < 10) ? count : 10;
2718         if (copy_from_user(buff, buffer, num))
2719                 return -EFAULT;
2720         buff[num] = '\0';
2721         sg_allow_dio = simple_strtoul(buff, NULL, 10) ? 1 : 0;
2722         return count;
2723 }
2724
2725 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2726 {
2727         return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2728 }
2729
2730 static ssize_t
2731 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2732                      size_t count, loff_t *off)
2733 {
2734         int num;
2735         unsigned long k = ULONG_MAX;
2736         char buff[11];
2737
2738         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2739                 return -EACCES;
2740         num = (count < 10) ? count : 10;
2741         if (copy_from_user(buff, buffer, num))
2742                 return -EFAULT;
2743         buff[num] = '\0';
2744         k = simple_strtoul(buff, NULL, 10);
2745         if (k <= 1048576) {     /* limit "big buff" to 1 MB */
2746                 sg_big_buff = k;
2747                 return count;
2748         }
2749         return -ERANGE;
2750 }
2751
2752 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2753 {
2754         seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2755                    sg_version_date);
2756         return 0;
2757 }
2758
2759 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2760 {
2761         return single_open(file, sg_proc_seq_show_version, NULL);
2762 }
2763
2764 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2765 {
2766         seq_printf(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\t"
2767                    "online\n");
2768         return 0;
2769 }
2770
2771 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2772 {
2773         return single_open(file, sg_proc_seq_show_devhdr, NULL);
2774 }
2775
2776 struct sg_proc_deviter {
2777         loff_t  index;
2778         size_t  max;
2779 };
2780
2781 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2782 {
2783         struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2784
2785         s->private = it;
2786         if (! it)
2787                 return NULL;
2788
2789         it->index = *pos;
2790         it->max = sg_last_dev();
2791         if (it->index >= it->max)
2792                 return NULL;
2793         return it;
2794 }
2795
2796 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2797 {
2798         struct sg_proc_deviter * it = s->private;
2799
2800         *pos = ++it->index;
2801         return (it->index < it->max) ? it : NULL;
2802 }
2803
2804 static void dev_seq_stop(struct seq_file *s, void *v)
2805 {
2806         kfree(s->private);
2807 }
2808
2809 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2810 {
2811         return seq_open(file, &dev_seq_ops);
2812 }
2813
2814 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2815 {
2816         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2817         Sg_device *sdp;
2818         struct scsi_device *scsidp;
2819
2820         sdp = it ? sg_get_dev(it->index) : NULL;
2821         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2822                 seq_printf(s, "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n",
2823                               scsidp->host->host_no, scsidp->channel,
2824                               scsidp->id, scsidp->lun, (int) scsidp->type,
2825                               1,
2826                               (int) scsidp->queue_depth,
2827                               (int) scsidp->device_busy,
2828                               (int) scsi_device_online(scsidp));
2829         else
2830                 seq_printf(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2831         return 0;
2832 }
2833
2834 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2835 {
2836         return seq_open(file, &devstrs_seq_ops);
2837 }
2838
2839 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2840 {
2841         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2842         Sg_device *sdp;
2843         struct scsi_device *scsidp;
2844
2845         sdp = it ? sg_get_dev(it->index) : NULL;
2846         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2847                 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2848                            scsidp->vendor, scsidp->model, scsidp->rev);
2849         else
2850                 seq_printf(s, "<no active device>\n");
2851         return 0;
2852 }
2853
2854 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2855 {
2856         int k, m, new_interface, blen, usg;
2857         Sg_request *srp;
2858         Sg_fd *fp;
2859         const sg_io_hdr_t *hp;
2860         const char * cp;
2861         unsigned int ms;
2862
2863         for (k = 0; (fp = sg_get_nth_sfp(sdp, k)); ++k) {
2864                 seq_printf(s, "   FD(%d): timeout=%dms bufflen=%d "
2865                            "(res)sgat=%d low_dma=%d\n", k + 1,
2866                            jiffies_to_msecs(fp->timeout),
2867                            fp->reserve.bufflen,
2868                            (int) fp->reserve.k_use_sg,
2869                            (int) fp->low_dma);
2870                 seq_printf(s, "   cmd_q=%d f_packid=%d k_orphan=%d closed=%d\n",
2871                            (int) fp->cmd_q, (int) fp->force_packid,
2872                            (int) fp->keep_orphan, (int) fp->closed);
2873                 for (m = 0; (srp = sg_get_nth_request(fp, m)); ++m) {
2874                         hp = &srp->header;
2875                         new_interface = (hp->interface_id == '\0') ? 0 : 1;
2876                         if (srp->res_used) {
2877                                 if (new_interface &&
2878                                     (SG_FLAG_MMAP_IO & hp->flags))
2879                                         cp = "     mmap>> ";
2880                                 else
2881                                         cp = "     rb>> ";
2882                         } else {
2883                                 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2884                                         cp = "     dio>> ";
2885                                 else
2886                                         cp = "     ";
2887                         }
2888                         seq_printf(s, cp);
2889                         blen = srp->data.bufflen;
2890                         usg = srp->data.k_use_sg;
2891                         seq_printf(s, srp->done ?
2892                                    ((1 == srp->done) ?  "rcv:" : "fin:")
2893                                    : "act:");
2894                         seq_printf(s, " id=%d blen=%d",
2895                                    srp->header.pack_id, blen);
2896                         if (srp->done)
2897                                 seq_printf(s, " dur=%d", hp->duration);
2898                         else {
2899                                 ms = jiffies_to_msecs(jiffies);
2900                                 seq_printf(s, " t_o/elap=%d/%d",
2901                                         (new_interface ? hp->timeout :
2902                                                   jiffies_to_msecs(fp->timeout)),
2903                                         (ms > hp->duration ? ms - hp->duration : 0));
2904                         }
2905                         seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2906                                    (int) srp->data.cmd_opcode);
2907                 }
2908                 if (0 == m)
2909                         seq_printf(s, "     No requests active\n");
2910         }
2911 }
2912
2913 static int sg_proc_open_debug(struct inode *inode, struct file *file)
2914 {
2915         return seq_open(file, &debug_seq_ops);
2916 }
2917
2918 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2919 {
2920         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2921         Sg_device *sdp;
2922
2923         if (it && (0 == it->index)) {
2924                 seq_printf(s, "max_active_device=%d(origin 1)\n",
2925                            (int)it->max);
2926                 seq_printf(s, " def_reserved_size=%d\n", sg_big_buff);
2927         }
2928         sdp = it ? sg_get_dev(it->index) : NULL;
2929         if (sdp) {
2930                 struct scsi_device *scsidp = sdp->device;
2931
2932                 if (NULL == scsidp) {
2933                         seq_printf(s, "device %d detached ??\n",
2934                                    (int)it->index);
2935                         return 0;
2936                 }
2937
2938                 if (sg_get_nth_sfp(sdp, 0)) {
2939                         seq_printf(s, " >>> device=%s ",
2940                                 sdp->disk->disk_name);
2941                         if (sdp->detached)
2942                                 seq_printf(s, "detached pending close ");
2943                         else
2944                                 seq_printf
2945                                     (s, "scsi%d chan=%d id=%d lun=%d   em=%d",
2946                                      scsidp->host->host_no,
2947                                      scsidp->channel, scsidp->id,
2948                                      scsidp->lun,
2949                                      scsidp->host->hostt->emulated);
2950                         seq_printf(s, " sg_tablesize=%d excl=%d\n",
2951                                    sdp->sg_tablesize, sdp->exclude);
2952                 }
2953                 sg_proc_debug_helper(s, sdp);
2954         }
2955         return 0;
2956 }
2957
2958 #endif                          /* CONFIG_SCSI_PROC_FS */
2959
2960 module_init(init_sg);
2961 module_exit(exit_sg);