git.oblomov.eu Git - linux-2.6/blob - drivers/scsi/sg.c

   1 /*
   2  *  History:
   3  *  Started: Aug 9 by Lawrence Foard (entropy@world.std.com),
   4  *           to allow user process control of SCSI devices.
   5  *  Development Sponsored by Killy Corp. NY NY
   6  *
   7  * Original driver (sg.c):
   8  *        Copyright (C) 1992 Lawrence Foard
   9  * Version 2 and 3 extensions to driver:
  10  *        Copyright (C) 1998 - 2005 Douglas Gilbert
  11  *
  12  *  Modified  19-JAN-1998  Richard Gooch <rgooch@atnf.csiro.au>  Devfs support
  13  *
  14  * This program is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2, or (at your option)
  17  * any later version.
  18  *
  19  */
  20
  21 static int sg_version_num = 30533;      /* 2 digits for each component */
  22 #define SG_VERSION_STR "3.5.33"
  23
  24 /*
  25  *  D. P. Gilbert (dgilbert@interlog.com, dougg@triode.net.au), notes:
  26  *      - scsi logging is available via SCSI_LOG_TIMEOUT macros. First
  27  *        the kernel/module needs to be built with CONFIG_SCSI_LOGGING
  28  *        (otherwise the macros compile to empty statements).
  29  *
  30  */
  31 #include <linux/config.h>
  32 #include <linux/module.h>
  33
  34 #include <linux/fs.h>
  35 #include <linux/kernel.h>
  36 #include <linux/sched.h>
  37 #include <linux/string.h>
  38 #include <linux/mm.h>
  39 #include <linux/errno.h>
  40 #include <linux/mtio.h>
  41 #include <linux/ioctl.h>
  42 #include <linux/fcntl.h>
  43 #include <linux/init.h>
  44 #include <linux/poll.h>
  45 #include <linux/smp_lock.h>
  46 #include <linux/moduleparam.h>
  47 #include <linux/devfs_fs_kernel.h>
  48 #include <linux/cdev.h>
  49 #include <linux/seq_file.h>
  50 #include <linux/blkdev.h>
  51 #include <linux/delay.h>
  52 #include <linux/scatterlist.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 = "20050908";
  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 #define SG_SECTOR_SZ 512
 100 #define SG_SECTOR_MSK (SG_SECTOR_SZ - 1)
 101
 102 #define SG_DEV_ARR_LUMP 32      /* amount to over allocate sg_dev_arr by */
 103
 104 static int sg_add(struct class_device *, struct class_interface *);
 105 static void sg_remove(struct class_device *, struct class_interface *);
 106
 107 static DEFINE_RWLOCK(sg_dev_arr_lock);  /* Also used to lock
 108                                                            file descriptor list for device */
 109
 110 static struct class_interface sg_interface = {
 111         .add            = sg_add,
 112         .remove         = sg_remove,
 113 };
 114
 115 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
 116         unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
 117         unsigned short sglist_len; /* size of malloc'd scatter-gather list ++ */
 118         unsigned bufflen;       /* Size of (aggregate) data buffer */
 119         unsigned b_malloc_len;  /* actual len malloc'ed in buffer */
 120         struct scatterlist *buffer;/* scatter list */
 121         char dio_in_use;        /* 0->indirect IO (or mmap), 1->dio */
 122         unsigned char cmd_opcode; /* first byte of command */
 123 } Sg_scatter_hold;
 124
 125 struct sg_device;               /* forward declarations */
 126 struct sg_fd;
 127
 128 typedef struct sg_request {     /* SG_MAX_QUEUE requests outstanding per file */
 129         struct sg_request *nextrp;      /* NULL -> tail request (slist) */
 130         struct sg_fd *parentfp; /* NULL -> not in use */
 131         Sg_scatter_hold data;   /* hold buffer, perhaps scatter list */
 132         sg_io_hdr_t header;     /* scsi command+info, see <scsi/sg.h> */
 133         unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
 134         char res_used;          /* 1 -> using reserve buffer, 0 -> not ... */
 135         char orphan;            /* 1 -> drop on sight, 0 -> normal */
 136         char sg_io_owned;       /* 1 -> packet belongs to SG_IO */
 137         volatile char done;     /* 0->before bh, 1->before read, 2->read */
 138 } Sg_request;
 139
 140 typedef struct sg_fd {          /* holds the state of a file descriptor */
 141         struct sg_fd *nextfp;   /* NULL when last opened fd on this device */
 142         struct sg_device *parentdp;     /* owning device */
 143         wait_queue_head_t read_wait;    /* queue read until command done */
 144         rwlock_t rq_list_lock;  /* protect access to list in req_arr */
 145         int timeout;            /* defaults to SG_DEFAULT_TIMEOUT      */
 146         int timeout_user;       /* defaults to SG_DEFAULT_TIMEOUT_USER */
 147         Sg_scatter_hold reserve;        /* buffer held for this file descriptor */
 148         unsigned save_scat_len; /* original length of trunc. scat. element */
 149         Sg_request *headrp;     /* head of request slist, NULL->empty */
 150         struct fasync_struct *async_qp; /* used by asynchronous notification */
 151         Sg_request req_arr[SG_MAX_QUEUE];       /* used as singly-linked list */
 152         char low_dma;           /* as in parent but possibly overridden to 1 */
 153         char force_packid;      /* 1 -> pack_id input to read(), 0 -> ignored */
 154         volatile char closed;   /* 1 -> fd closed but request(s) outstanding */
 155         char cmd_q;             /* 1 -> allow command queuing, 0 -> don't */
 156         char next_cmd_len;      /* 0 -> automatic (def), >0 -> use on next write() */
 157         char keep_orphan;       /* 0 -> drop orphan (def), 1 -> keep for read() */
 158         char mmap_called;       /* 0 -> mmap() never called on this fd */
 159 } Sg_fd;
 160
 161 typedef struct sg_device { /* holds the state of each scsi generic device */
 162         struct scsi_device *device;
 163         wait_queue_head_t o_excl_wait;  /* queue open() when O_EXCL in use */
 164         int sg_tablesize;       /* adapter's max scatter-gather table size */
 165         Sg_fd *headfp;          /* first open fd belonging to this device */
 166         volatile char detached; /* 0->attached, 1->detached pending removal */
 167         volatile char exclude;  /* opened for exclusive access */
 168         char sgdebug;           /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
 169         struct gendisk *disk;
 170         struct cdev * cdev;     /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
 171 } Sg_device;
 172
 173 static int sg_fasync(int fd, struct file *filp, int mode);
 174 /* tasklet or soft irq callback */
 175 static void sg_cmd_done(void *data, char *sense, int result, int resid);
 176 static int sg_start_req(Sg_request * srp);
 177 static void sg_finish_rem_req(Sg_request * srp);
 178 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
 179 static int sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp,
 180                          int tablesize);
 181 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
 182                            Sg_request * srp);
 183 static ssize_t sg_new_write(Sg_fd * sfp, const char __user *buf, size_t count,
 184                             int blocking, int read_only, Sg_request ** o_srp);
 185 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
 186                            unsigned char *cmnd, int timeout, int blocking);
 187 static int sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
 188                       int wr_xf, int *countp, unsigned char __user **up);
 189 static int sg_write_xfer(Sg_request * srp);
 190 static int sg_read_xfer(Sg_request * srp);
 191 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
 192 static void sg_remove_scat(Sg_scatter_hold * schp);
 193 static void sg_build_reserve(Sg_fd * sfp, int req_size);
 194 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
 195 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
 196 static struct page *sg_page_malloc(int rqSz, int lowDma, int *retSzp);
 197 static void sg_page_free(struct page *page, int size);
 198 static Sg_fd *sg_add_sfp(Sg_device * sdp, int dev);
 199 static int sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
 200 static void __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
 201 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
 202 static Sg_request *sg_add_request(Sg_fd * sfp);
 203 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
 204 static int sg_res_in_use(Sg_fd * sfp);
 205 static int sg_allow_access(unsigned char opcode, char dev_type);
 206 static int sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len);
 207 static Sg_device *sg_get_dev(int dev);
 208 #ifdef CONFIG_SCSI_PROC_FS
 209 static int sg_last_dev(void);
 210 #endif
 211
 212 static Sg_device **sg_dev_arr = NULL;
 213 static int sg_dev_max;
 214 static int sg_nr_dev;
 215
 216 #define SZ_SG_HEADER sizeof(struct sg_header)
 217 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
 218 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
 219 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
 220
 221 static int
 222 sg_open(struct inode *inode, struct file *filp)
 223 {
 224         int dev = iminor(inode);
 225         int flags = filp->f_flags;
 226         struct request_queue *q;
 227         Sg_device *sdp;
 228         Sg_fd *sfp;
 229         int res;
 230         int retval;
 231
 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                 return -ENXIO;
 237         if (sdp->detached)
 238                 return -ENODEV;
 239
 240         /* This driver's module count bumped by fops_get in <linux/fs.h> */
 241         /* Prevent the device driver from vanishing while we sleep */
 242         retval = scsi_device_get(sdp->device);
 243         if (retval)
 244                 return retval;
 245
 246         if (!((flags & O_NONBLOCK) ||
 247               scsi_block_when_processing_errors(sdp->device))) {
 248                 retval = -ENXIO;
 249                 /* we are in error recovery for this device */
 250                 goto error_out;
 251         }
 252
 253         if (flags & O_EXCL) {
 254                 if (O_RDONLY == (flags & O_ACCMODE)) {
 255                         retval = -EPERM; /* Can't lock it with read only access */
 256                         goto error_out;
 257                 }
 258                 if (sdp->headfp && (flags & O_NONBLOCK)) {
 259                         retval = -EBUSY;
 260                         goto error_out;
 261                 }
 262                 res = 0;
 263                 __wait_event_interruptible(sdp->o_excl_wait,
 264                         ((sdp->headfp || sdp->exclude) ? 0 : (sdp->exclude = 1)), res);
 265                 if (res) {
 266                         retval = res;   /* -ERESTARTSYS because signal hit process */
 267                         goto error_out;
 268                 }
 269         } else if (sdp->exclude) {      /* some other fd has an exclusive lock on dev */
 270                 if (flags & O_NONBLOCK) {
 271                         retval = -EBUSY;
 272                         goto error_out;
 273                 }
 274                 res = 0;
 275                 __wait_event_interruptible(sdp->o_excl_wait, (!sdp->exclude),
 276                                            res);
 277                 if (res) {
 278                         retval = res;   /* -ERESTARTSYS because signal hit process */
 279                         goto error_out;
 280                 }
 281         }
 282         if (sdp->detached) {
 283                 retval = -ENODEV;
 284                 goto error_out;
 285         }
 286         if (!sdp->headfp) {     /* no existing opens on this device */
 287                 sdp->sgdebug = 0;
 288                 q = sdp->device->request_queue;
 289                 sdp->sg_tablesize = min(q->max_hw_segments,
 290                                         q->max_phys_segments);
 291         }
 292         if ((sfp = sg_add_sfp(sdp, dev)))
 293                 filp->private_data = sfp;
 294         else {
 295                 if (flags & O_EXCL)
 296                         sdp->exclude = 0;       /* undo if error */
 297                 retval = -ENOMEM;
 298                 goto error_out;
 299         }
 300         return 0;
 301
 302       error_out:
 303         scsi_device_put(sdp->device);
 304         return retval;
 305 }
 306
 307 /* Following function was formerly called 'sg_close' */
 308 static int
 309 sg_release(struct inode *inode, struct file *filp)
 310 {
 311         Sg_device *sdp;
 312         Sg_fd *sfp;
 313
 314         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 315                 return -ENXIO;
 316         SCSI_LOG_TIMEOUT(3, printk("sg_release: %s\n", sdp->disk->disk_name));
 317         sg_fasync(-1, filp, 0); /* remove filp from async notification list */
 318         if (0 == sg_remove_sfp(sdp, sfp)) {     /* Returns 1 when sdp gone */
 319                 if (!sdp->detached) {
 320                         scsi_device_put(sdp->device);
 321                 }
 322                 sdp->exclude = 0;
 323                 wake_up_interruptible(&sdp->o_excl_wait);
 324         }
 325         return 0;
 326 }
 327
 328 static ssize_t
 329 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
 330 {
 331         Sg_device *sdp;
 332         Sg_fd *sfp;
 333         Sg_request *srp;
 334         int req_pack_id = -1;
 335         sg_io_hdr_t *hp;
 336         struct sg_header *old_hdr = NULL;
 337         int retval = 0;
 338
 339         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 340                 return -ENXIO;
 341         SCSI_LOG_TIMEOUT(3, printk("sg_read: %s, count=%d\n",
 342                                    sdp->disk->disk_name, (int) count));
 343
 344         if (!access_ok(VERIFY_WRITE, buf, count))
 345                 return -EFAULT;
 346         if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
 347                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 348                 if (!old_hdr)
 349                         return -ENOMEM;
 350                 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
 351                         retval = -EFAULT;
 352                         goto free_old_hdr;
 353                 }
 354                 if (old_hdr->reply_len < 0) {
 355                         if (count >= SZ_SG_IO_HDR) {
 356                                 sg_io_hdr_t *new_hdr;
 357                                 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
 358                                 if (!new_hdr) {
 359                                         retval = -ENOMEM;
 360                                         goto free_old_hdr;
 361                                 }
 362                                 retval =__copy_from_user
 363                                     (new_hdr, buf, SZ_SG_IO_HDR);
 364                                 req_pack_id = new_hdr->pack_id;
 365                                 kfree(new_hdr);
 366                                 if (retval) {
 367                                         retval = -EFAULT;
 368                                         goto free_old_hdr;
 369                                 }
 370                         }
 371                 } else
 372                         req_pack_id = old_hdr->pack_id;
 373         }
 374         srp = sg_get_rq_mark(sfp, req_pack_id);
 375         if (!srp) {             /* now wait on packet to arrive */
 376                 if (sdp->detached) {
 377                         retval = -ENODEV;
 378                         goto free_old_hdr;
 379                 }
 380                 if (filp->f_flags & O_NONBLOCK) {
 381                         retval = -EAGAIN;
 382                         goto free_old_hdr;
 383                 }
 384                 while (1) {
 385                         retval = 0; /* following macro beats race condition */
 386                         __wait_event_interruptible(sfp->read_wait,
 387                                 (sdp->detached ||
 388                                 (srp = sg_get_rq_mark(sfp, req_pack_id))),
 389                                 retval);
 390                         if (sdp->detached) {
 391                                 retval = -ENODEV;
 392                                 goto free_old_hdr;
 393                         }
 394                         if (0 == retval)
 395                                 break;
 396
 397                         /* -ERESTARTSYS as signal hit process */
 398                         goto free_old_hdr;
 399                 }
 400         }
 401         if (srp->header.interface_id != '\0') {
 402                 retval = sg_new_read(sfp, buf, count, srp);
 403                 goto free_old_hdr;
 404         }
 405
 406         hp = &srp->header;
 407         if (old_hdr == NULL) {
 408                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 409                 if (! old_hdr) {
 410                         retval = -ENOMEM;
 411                         goto free_old_hdr;
 412                 }
 413         }
 414         memset(old_hdr, 0, SZ_SG_HEADER);
 415         old_hdr->reply_len = (int) hp->timeout;
 416         old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
 417         old_hdr->pack_id = hp->pack_id;
 418         old_hdr->twelve_byte =
 419             ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
 420         old_hdr->target_status = hp->masked_status;
 421         old_hdr->host_status = hp->host_status;
 422         old_hdr->driver_status = hp->driver_status;
 423         if ((CHECK_CONDITION & hp->masked_status) ||
 424             (DRIVER_SENSE & hp->driver_status))
 425                 memcpy(old_hdr->sense_buffer, srp->sense_b,
 426                        sizeof (old_hdr->sense_buffer));
 427         switch (hp->host_status) {
 428         /* This setup of 'result' is for backward compatibility and is best
 429            ignored by the user who should use target, host + driver status */
 430         case DID_OK:
 431         case DID_PASSTHROUGH:
 432         case DID_SOFT_ERROR:
 433                 old_hdr->result = 0;
 434                 break;
 435         case DID_NO_CONNECT:
 436         case DID_BUS_BUSY:
 437         case DID_TIME_OUT:
 438                 old_hdr->result = EBUSY;
 439                 break;
 440         case DID_BAD_TARGET:
 441         case DID_ABORT:
 442         case DID_PARITY:
 443         case DID_RESET:
 444         case DID_BAD_INTR:
 445                 old_hdr->result = EIO;
 446                 break;
 447         case DID_ERROR:
 448                 old_hdr->result = (srp->sense_b[0] == 0 &&
 449                                   hp->masked_status == GOOD) ? 0 : EIO;
 450                 break;
 451         default:
 452                 old_hdr->result = EIO;
 453                 break;
 454         }
 455
 456         /* Now copy the result back to the user buffer.  */
 457         if (count >= SZ_SG_HEADER) {
 458                 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
 459                         retval = -EFAULT;
 460                         goto free_old_hdr;
 461                 }
 462                 buf += SZ_SG_HEADER;
 463                 if (count > old_hdr->reply_len)
 464                         count = old_hdr->reply_len;
 465                 if (count > SZ_SG_HEADER) {
 466                         if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
 467                                 retval = -EFAULT;
 468                                 goto free_old_hdr;
 469                         }
 470                 }
 471         } else
 472                 count = (old_hdr->result == 0) ? 0 : -EIO;
 473         sg_finish_rem_req(srp);
 474         retval = count;
 475 free_old_hdr:
 476         kfree(old_hdr);
 477         return retval;
 478 }
 479
 480 static ssize_t
 481 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
 482 {
 483         sg_io_hdr_t *hp = &srp->header;
 484         int err = 0;
 485         int len;
 486
 487         if (count < SZ_SG_IO_HDR) {
 488                 err = -EINVAL;
 489                 goto err_out;
 490         }
 491         hp->sb_len_wr = 0;
 492         if ((hp->mx_sb_len > 0) && hp->sbp) {
 493                 if ((CHECK_CONDITION & hp->masked_status) ||
 494                     (DRIVER_SENSE & hp->driver_status)) {
 495                         int sb_len = SCSI_SENSE_BUFFERSIZE;
 496                         sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
 497                         len = 8 + (int) srp->sense_b[7];        /* Additional sense length field */
 498                         len = (len > sb_len) ? sb_len : len;
 499                         if (copy_to_user(hp->sbp, srp->sense_b, len)) {
 500                                 err = -EFAULT;
 501                                 goto err_out;
 502                         }
 503                         hp->sb_len_wr = len;
 504                 }
 505         }
 506         if (hp->masked_status || hp->host_status || hp->driver_status)
 507                 hp->info |= SG_INFO_CHECK;
 508         if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
 509                 err = -EFAULT;
 510                 goto err_out;
 511         }
 512         err = sg_read_xfer(srp);
 513       err_out:
 514         sg_finish_rem_req(srp);
 515         return (0 == err) ? count : err;
 516 }
 517
 518 static ssize_t
 519 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
 520 {
 521         int mxsize, cmd_size, k;
 522         int input_size, blocking;
 523         unsigned char opcode;
 524         Sg_device *sdp;
 525         Sg_fd *sfp;
 526         Sg_request *srp;
 527         struct sg_header old_hdr;
 528         sg_io_hdr_t *hp;
 529         unsigned char cmnd[MAX_COMMAND_SIZE];
 530
 531         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 532                 return -ENXIO;
 533         SCSI_LOG_TIMEOUT(3, printk("sg_write: %s, count=%d\n",
 534                                    sdp->disk->disk_name, (int) count));
 535         if (sdp->detached)
 536                 return -ENODEV;
 537         if (!((filp->f_flags & O_NONBLOCK) ||
 538               scsi_block_when_processing_errors(sdp->device)))
 539                 return -ENXIO;
 540
 541         if (!access_ok(VERIFY_READ, buf, count))
 542                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 543         if (count < SZ_SG_HEADER)
 544                 return -EIO;
 545         if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
 546                 return -EFAULT;
 547         blocking = !(filp->f_flags & O_NONBLOCK);
 548         if (old_hdr.reply_len < 0)
 549                 return sg_new_write(sfp, buf, count, blocking, 0, NULL);
 550         if (count < (SZ_SG_HEADER + 6))
 551                 return -EIO;    /* The minimum scsi command length is 6 bytes. */
 552
 553         if (!(srp = sg_add_request(sfp))) {
 554                 SCSI_LOG_TIMEOUT(1, printk("sg_write: queue full\n"));
 555                 return -EDOM;
 556         }
 557         buf += SZ_SG_HEADER;
 558         __get_user(opcode, buf);
 559         if (sfp->next_cmd_len > 0) {
 560                 if (sfp->next_cmd_len > MAX_COMMAND_SIZE) {
 561                         SCSI_LOG_TIMEOUT(1, printk("sg_write: command length too long\n"));
 562                         sfp->next_cmd_len = 0;
 563                         sg_remove_request(sfp, srp);
 564                         return -EIO;
 565                 }
 566                 cmd_size = sfp->next_cmd_len;
 567                 sfp->next_cmd_len = 0;  /* reset so only this write() effected */
 568         } else {
 569                 cmd_size = COMMAND_SIZE(opcode);        /* based on SCSI command group */
 570                 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
 571                         cmd_size = 12;
 572         }
 573         SCSI_LOG_TIMEOUT(4, printk(
 574                 "sg_write:   scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
 575 /* Determine buffer size.  */
 576         input_size = count - cmd_size;
 577         mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
 578         mxsize -= SZ_SG_HEADER;
 579         input_size -= SZ_SG_HEADER;
 580         if (input_size < 0) {
 581                 sg_remove_request(sfp, srp);
 582                 return -EIO;    /* User did not pass enough bytes for this command. */
 583         }
 584         hp = &srp->header;
 585         hp->interface_id = '\0';        /* indicator of old interface tunnelled */
 586         hp->cmd_len = (unsigned char) cmd_size;
 587         hp->iovec_count = 0;
 588         hp->mx_sb_len = 0;
 589         if (input_size > 0)
 590                 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
 591                     SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
 592         else
 593                 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
 594         hp->dxfer_len = mxsize;
 595         hp->dxferp = (char __user *)buf + cmd_size;
 596         hp->sbp = NULL;
 597         hp->timeout = old_hdr.reply_len;        /* structure abuse ... */
 598         hp->flags = input_size; /* structure abuse ... */
 599         hp->pack_id = old_hdr.pack_id;
 600         hp->usr_ptr = NULL;
 601         if (__copy_from_user(cmnd, buf, cmd_size))
 602                 return -EFAULT;
 603         /*
 604          * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
 605          * but is is possible that the app intended SG_DXFER_TO_DEV, because there
 606          * is a non-zero input_size, so emit a warning.
 607          */
 608         if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV)
 609                 if (printk_ratelimit())
 610                         printk(KERN_WARNING
 611                                "sg_write: data in/out %d/%d bytes for SCSI command 0x%x--"
 612                                "guessing data in;\n" KERN_WARNING "   "
 613                                "program %s not setting count and/or reply_len properly\n",
 614                                old_hdr.reply_len - (int)SZ_SG_HEADER,
 615                                input_size, (unsigned int) cmnd[0],
 616                                current->comm);
 617         k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
 618         return (k < 0) ? k : count;
 619 }
 620
 621 static ssize_t
 622 sg_new_write(Sg_fd * sfp, const char __user *buf, size_t count,
 623              int blocking, int read_only, Sg_request ** o_srp)
 624 {
 625         int k;
 626         Sg_request *srp;
 627         sg_io_hdr_t *hp;
 628         unsigned char cmnd[MAX_COMMAND_SIZE];
 629         int timeout;
 630         unsigned long ul_timeout;
 631
 632         if (count < SZ_SG_IO_HDR)
 633                 return -EINVAL;
 634         if (!access_ok(VERIFY_READ, buf, count))
 635                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 636
 637         sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
 638         if (!(srp = sg_add_request(sfp))) {
 639                 SCSI_LOG_TIMEOUT(1, printk("sg_new_write: queue full\n"));
 640                 return -EDOM;
 641         }
 642         hp = &srp->header;
 643         if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
 644                 sg_remove_request(sfp, srp);
 645                 return -EFAULT;
 646         }
 647         if (hp->interface_id != 'S') {
 648                 sg_remove_request(sfp, srp);
 649                 return -ENOSYS;
 650         }
 651         if (hp->flags & SG_FLAG_MMAP_IO) {
 652                 if (hp->dxfer_len > sfp->reserve.bufflen) {
 653                         sg_remove_request(sfp, srp);
 654                         return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
 655                 }
 656                 if (hp->flags & SG_FLAG_DIRECT_IO) {
 657                         sg_remove_request(sfp, srp);
 658                         return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
 659                 }
 660                 if (sg_res_in_use(sfp)) {
 661                         sg_remove_request(sfp, srp);
 662                         return -EBUSY;  /* reserve buffer already being used */
 663                 }
 664         }
 665         ul_timeout = msecs_to_jiffies(srp->header.timeout);
 666         timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
 667         if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
 668                 sg_remove_request(sfp, srp);
 669                 return -EMSGSIZE;
 670         }
 671         if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
 672                 sg_remove_request(sfp, srp);
 673                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 674         }
 675         if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
 676                 sg_remove_request(sfp, srp);
 677                 return -EFAULT;
 678         }
 679         if (read_only &&
 680             (!sg_allow_access(cmnd[0], sfp->parentdp->device->type))) {
 681                 sg_remove_request(sfp, srp);
 682                 return -EPERM;
 683         }
 684         k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
 685         if (k < 0)
 686                 return k;
 687         if (o_srp)
 688                 *o_srp = srp;
 689         return count;
 690 }
 691
 692 static int
 693 sg_common_write(Sg_fd * sfp, Sg_request * srp,
 694                 unsigned char *cmnd, int timeout, int blocking)
 695 {
 696         int k, data_dir;
 697         Sg_device *sdp = sfp->parentdp;
 698         sg_io_hdr_t *hp = &srp->header;
 699
 700         srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
 701         hp->status = 0;
 702         hp->masked_status = 0;
 703         hp->msg_status = 0;
 704         hp->info = 0;
 705         hp->host_status = 0;
 706         hp->driver_status = 0;
 707         hp->resid = 0;
 708         SCSI_LOG_TIMEOUT(4, printk("sg_common_write:  scsi opcode=0x%02x, cmd_size=%d\n",
 709                           (int) cmnd[0], (int) hp->cmd_len));
 710
 711         if ((k = sg_start_req(srp))) {
 712                 SCSI_LOG_TIMEOUT(1, printk("sg_write: start_req err=%d\n", k));
 713                 sg_finish_rem_req(srp);
 714                 return k;       /* probably out of space --> ENOMEM */
 715         }
 716         if ((k = sg_write_xfer(srp))) {
 717                 SCSI_LOG_TIMEOUT(1, printk("sg_write: write_xfer, bad address\n"));
 718                 sg_finish_rem_req(srp);
 719                 return k;
 720         }
 721         if (sdp->detached) {
 722                 sg_finish_rem_req(srp);
 723                 return -ENODEV;
 724         }
 725
 726         switch (hp->dxfer_direction) {
 727         case SG_DXFER_TO_FROM_DEV:
 728         case SG_DXFER_FROM_DEV:
 729                 data_dir = DMA_FROM_DEVICE;
 730                 break;
 731         case SG_DXFER_TO_DEV:
 732                 data_dir = DMA_TO_DEVICE;
 733                 break;
 734         case SG_DXFER_UNKNOWN:
 735                 data_dir = DMA_BIDIRECTIONAL;
 736                 break;
 737         default:
 738                 data_dir = DMA_NONE;
 739                 break;
 740         }
 741         hp->duration = jiffies_to_msecs(jiffies);
 742 /* Now send everything of to mid-level. The next time we hear about this
 743    packet is when sg_cmd_done() is called (i.e. a callback). */
 744         if (scsi_execute_async(sdp->device, cmnd, data_dir, srp->data.buffer,
 745                                 hp->dxfer_len, srp->data.k_use_sg, timeout,
 746                                 SG_DEFAULT_RETRIES, srp, sg_cmd_done,
 747                                 GFP_ATOMIC)) {
 748                 SCSI_LOG_TIMEOUT(1, printk("sg_write: scsi_execute_async failed\n"));
 749                 /*
 750                  * most likely out of mem, but could also be a bad map
 751                  */
 752                 return -ENOMEM;
 753         } else
 754                 return 0;
 755 }
 756
 757 static int
 758 sg_srp_done(Sg_request *srp, Sg_fd *sfp)
 759 {
 760         unsigned long iflags;
 761         int done;
 762
 763         read_lock_irqsave(&sfp->rq_list_lock, iflags);
 764         done = srp->done;
 765         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 766         return done;
 767 }
 768
 769 static int
 770 sg_ioctl(struct inode *inode, struct file *filp,
 771          unsigned int cmd_in, unsigned long arg)
 772 {
 773         void __user *p = (void __user *)arg;
 774         int __user *ip = p;
 775         int result, val, read_only;
 776         Sg_device *sdp;
 777         Sg_fd *sfp;
 778         Sg_request *srp;
 779         unsigned long iflags;
 780
 781         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 782                 return -ENXIO;
 783         SCSI_LOG_TIMEOUT(3, printk("sg_ioctl: %s, cmd=0x%x\n",
 784                                    sdp->disk->disk_name, (int) cmd_in));
 785         read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
 786
 787         switch (cmd_in) {
 788         case SG_IO:
 789                 {
 790                         int blocking = 1;       /* ignore O_NONBLOCK flag */
 791
 792                         if (sdp->detached)
 793                                 return -ENODEV;
 794                         if (!scsi_block_when_processing_errors(sdp->device))
 795                                 return -ENXIO;
 796                         if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
 797                                 return -EFAULT;
 798                         result =
 799                             sg_new_write(sfp, p, SZ_SG_IO_HDR,
 800                                          blocking, read_only, &srp);
 801                         if (result < 0)
 802                                 return result;
 803                         srp->sg_io_owned = 1;
 804                         while (1) {
 805                                 result = 0;     /* following macro to beat race condition */
 806                                 __wait_event_interruptible(sfp->read_wait,
 807                                         (sdp->detached || sfp->closed || sg_srp_done(srp, sfp)),
 808                                                            result);
 809                                 if (sdp->detached)
 810                                         return -ENODEV;
 811                                 if (sfp->closed)
 812                                         return 0;       /* request packet dropped already */
 813                                 if (0 == result)
 814                                         break;
 815                                 srp->orphan = 1;
 816                                 return result;  /* -ERESTARTSYS because signal hit process */
 817                         }
 818                         write_lock_irqsave(&sfp->rq_list_lock, iflags);
 819                         srp->done = 2;
 820                         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 821                         result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
 822                         return (result < 0) ? result : 0;
 823                 }
 824         case SG_SET_TIMEOUT:
 825                 result = get_user(val, ip);
 826                 if (result)
 827                         return result;
 828                 if (val < 0)
 829                         return -EIO;
 830                 if (val >= MULDIV (INT_MAX, USER_HZ, HZ))
 831                     val = MULDIV (INT_MAX, USER_HZ, HZ);
 832                 sfp->timeout_user = val;
 833                 sfp->timeout = MULDIV (val, HZ, USER_HZ);
 834
 835                 return 0;
 836         case SG_GET_TIMEOUT:    /* N.B. User receives timeout as return value */
 837                                 /* strange ..., for backward compatibility */
 838                 return sfp->timeout_user;
 839         case SG_SET_FORCE_LOW_DMA:
 840                 result = get_user(val, ip);
 841                 if (result)
 842                         return result;
 843                 if (val) {
 844                         sfp->low_dma = 1;
 845                         if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
 846                                 val = (int) sfp->reserve.bufflen;
 847                                 sg_remove_scat(&sfp->reserve);
 848                                 sg_build_reserve(sfp, val);
 849                         }
 850                 } else {
 851                         if (sdp->detached)
 852                                 return -ENODEV;
 853                         sfp->low_dma = sdp->device->host->unchecked_isa_dma;
 854                 }
 855                 return 0;
 856         case SG_GET_LOW_DMA:
 857                 return put_user((int) sfp->low_dma, ip);
 858         case SG_GET_SCSI_ID:
 859                 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
 860                         return -EFAULT;
 861                 else {
 862                         sg_scsi_id_t __user *sg_idp = p;
 863
 864                         if (sdp->detached)
 865                                 return -ENODEV;
 866                         __put_user((int) sdp->device->host->host_no,
 867                                    &sg_idp->host_no);
 868                         __put_user((int) sdp->device->channel,
 869                                    &sg_idp->channel);
 870                         __put_user((int) sdp->device->id, &sg_idp->scsi_id);
 871                         __put_user((int) sdp->device->lun, &sg_idp->lun);
 872                         __put_user((int) sdp->device->type, &sg_idp->scsi_type);
 873                         __put_user((short) sdp->device->host->cmd_per_lun,
 874                                    &sg_idp->h_cmd_per_lun);
 875                         __put_user((short) sdp->device->queue_depth,
 876                                    &sg_idp->d_queue_depth);
 877                         __put_user(0, &sg_idp->unused[0]);
 878                         __put_user(0, &sg_idp->unused[1]);
 879                         return 0;
 880                 }
 881         case SG_SET_FORCE_PACK_ID:
 882                 result = get_user(val, ip);
 883                 if (result)
 884                         return result;
 885                 sfp->force_packid = val ? 1 : 0;
 886                 return 0;
 887         case SG_GET_PACK_ID:
 888                 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
 889                         return -EFAULT;
 890                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 891                 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
 892                         if ((1 == srp->done) && (!srp->sg_io_owned)) {
 893                                 read_unlock_irqrestore(&sfp->rq_list_lock,
 894                                                        iflags);
 895                                 __put_user(srp->header.pack_id, ip);
 896                                 return 0;
 897                         }
 898                 }
 899                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 900                 __put_user(-1, ip);
 901                 return 0;
 902         case SG_GET_NUM_WAITING:
 903                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 904                 for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) {
 905                         if ((1 == srp->done) && (!srp->sg_io_owned))
 906                                 ++val;
 907                 }
 908                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 909                 return put_user(val, ip);
 910         case SG_GET_SG_TABLESIZE:
 911                 return put_user(sdp->sg_tablesize, ip);
 912         case SG_SET_RESERVED_SIZE:
 913                 result = get_user(val, ip);
 914                 if (result)
 915                         return result;
 916                 if (val < 0)
 917                         return -EINVAL;
 918                 if (val != sfp->reserve.bufflen) {
 919                         if (sg_res_in_use(sfp) || sfp->mmap_called)
 920                                 return -EBUSY;
 921                         sg_remove_scat(&sfp->reserve);
 922                         sg_build_reserve(sfp, val);
 923                 }
 924                 return 0;
 925         case SG_GET_RESERVED_SIZE:
 926                 val = (int) sfp->reserve.bufflen;
 927                 return put_user(val, ip);
 928         case SG_SET_COMMAND_Q:
 929                 result = get_user(val, ip);
 930                 if (result)
 931                         return result;
 932                 sfp->cmd_q = val ? 1 : 0;
 933                 return 0;
 934         case SG_GET_COMMAND_Q:
 935                 return put_user((int) sfp->cmd_q, ip);
 936         case SG_SET_KEEP_ORPHAN:
 937                 result = get_user(val, ip);
 938                 if (result)
 939                         return result;
 940                 sfp->keep_orphan = val;
 941                 return 0;
 942         case SG_GET_KEEP_ORPHAN:
 943                 return put_user((int) sfp->keep_orphan, ip);
 944         case SG_NEXT_CMD_LEN:
 945                 result = get_user(val, ip);
 946                 if (result)
 947                         return result;
 948                 sfp->next_cmd_len = (val > 0) ? val : 0;
 949                 return 0;
 950         case SG_GET_VERSION_NUM:
 951                 return put_user(sg_version_num, ip);
 952         case SG_GET_ACCESS_COUNT:
 953                 /* faked - we don't have a real access count anymore */
 954                 val = (sdp->device ? 1 : 0);
 955                 return put_user(val, ip);
 956         case SG_GET_REQUEST_TABLE:
 957                 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
 958                         return -EFAULT;
 959                 else {
 960                         sg_req_info_t *rinfo;
 961                         unsigned int ms;
 962
 963                         rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
 964                                                                 GFP_KERNEL);
 965                         if (!rinfo)
 966                                 return -ENOMEM;
 967                         read_lock_irqsave(&sfp->rq_list_lock, iflags);
 968                         for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE;
 969                              ++val, srp = srp ? srp->nextrp : srp) {
 970                                 memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
 971                                 if (srp) {
 972                                         rinfo[val].req_state = srp->done + 1;
 973                                         rinfo[val].problem =
 974                                             srp->header.masked_status &
 975                                             srp->header.host_status &
 976                                             srp->header.driver_status;
 977                                         if (srp->done)
 978                                                 rinfo[val].duration =
 979                                                         srp->header.duration;
 980                                         else {
 981                                                 ms = jiffies_to_msecs(jiffies);
 982                                                 rinfo[val].duration =
 983                                                     (ms > srp->header.duration) ?
 984                                                     (ms - srp->header.duration) : 0;
 985                                         }
 986                                         rinfo[val].orphan = srp->orphan;
 987                                         rinfo[val].sg_io_owned =
 988                                                         srp->sg_io_owned;
 989                                         rinfo[val].pack_id =
 990                                                         srp->header.pack_id;
 991                                         rinfo[val].usr_ptr =
 992                                                         srp->header.usr_ptr;
 993                                 }
 994                         }
 995                         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 996                         result = __copy_to_user(p, rinfo,
 997                                                 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
 998                         result = result ? -EFAULT : 0;
 999                         kfree(rinfo);
1000                         return result;
1001                 }
1002         case SG_EMULATED_HOST:
1003                 if (sdp->detached)
1004                         return -ENODEV;
1005                 return put_user(sdp->device->host->hostt->emulated, ip);
1006         case SG_SCSI_RESET:
1007                 if (sdp->detached)
1008                         return -ENODEV;
1009                 if (filp->f_flags & O_NONBLOCK) {
1010                         if (scsi_host_in_recovery(sdp->device->host))
1011                                 return -EBUSY;
1012                 } else if (!scsi_block_when_processing_errors(sdp->device))
1013                         return -EBUSY;
1014                 result = get_user(val, ip);
1015                 if (result)
1016                         return result;
1017                 if (SG_SCSI_RESET_NOTHING == val)
1018                         return 0;
1019                 switch (val) {
1020                 case SG_SCSI_RESET_DEVICE:
1021                         val = SCSI_TRY_RESET_DEVICE;
1022                         break;
1023                 case SG_SCSI_RESET_BUS:
1024                         val = SCSI_TRY_RESET_BUS;
1025                         break;
1026                 case SG_SCSI_RESET_HOST:
1027                         val = SCSI_TRY_RESET_HOST;
1028                         break;
1029                 default:
1030                         return -EINVAL;
1031                 }
1032                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1033                         return -EACCES;
1034                 return (scsi_reset_provider(sdp->device, val) ==
1035                         SUCCESS) ? 0 : -EIO;
1036         case SCSI_IOCTL_SEND_COMMAND:
1037                 if (sdp->detached)
1038                         return -ENODEV;
1039                 if (read_only) {
1040                         unsigned char opcode = WRITE_6;
1041                         Scsi_Ioctl_Command __user *siocp = p;
1042
1043                         if (copy_from_user(&opcode, siocp->data, 1))
1044                                 return -EFAULT;
1045                         if (!sg_allow_access(opcode, sdp->device->type))
1046                                 return -EPERM;
1047                 }
1048                 return scsi_ioctl_send_command(sdp->device, p);
1049         case SG_SET_DEBUG:
1050                 result = get_user(val, ip);
1051                 if (result)
1052                         return result;
1053                 sdp->sgdebug = (char) val;
1054                 return 0;
1055         case SCSI_IOCTL_GET_IDLUN:
1056         case SCSI_IOCTL_GET_BUS_NUMBER:
1057         case SCSI_IOCTL_PROBE_HOST:
1058         case SG_GET_TRANSFORM:
1059                 if (sdp->detached)
1060                         return -ENODEV;
1061                 return scsi_ioctl(sdp->device, cmd_in, p);
1062         default:
1063                 if (read_only)
1064                         return -EPERM;  /* don't know so take safe approach */
1065                 return scsi_ioctl(sdp->device, cmd_in, p);
1066         }
1067 }
1068
1069 #ifdef CONFIG_COMPAT
1070 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1071 {
1072         Sg_device *sdp;
1073         Sg_fd *sfp;
1074         struct scsi_device *sdev;
1075
1076         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1077                 return -ENXIO;
1078
1079         sdev = sdp->device;
1080         if (sdev->host->hostt->compat_ioctl) {
1081                 int ret;
1082
1083                 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1084
1085                 return ret;
1086         }
1087
1088         return -ENOIOCTLCMD;
1089 }
1090 #endif
1091
1092 static unsigned int
1093 sg_poll(struct file *filp, poll_table * wait)
1094 {
1095         unsigned int res = 0;
1096         Sg_device *sdp;
1097         Sg_fd *sfp;
1098         Sg_request *srp;
1099         int count = 0;
1100         unsigned long iflags;
1101
1102         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))
1103             || sfp->closed)
1104                 return POLLERR;
1105         poll_wait(filp, &sfp->read_wait, wait);
1106         read_lock_irqsave(&sfp->rq_list_lock, iflags);
1107         for (srp = sfp->headrp; srp; srp = srp->nextrp) {
1108                 /* if any read waiting, flag it */
1109                 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1110                         res = POLLIN | POLLRDNORM;
1111                 ++count;
1112         }
1113         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1114
1115         if (sdp->detached)
1116                 res |= POLLHUP;
1117         else if (!sfp->cmd_q) {
1118                 if (0 == count)
1119                         res |= POLLOUT | POLLWRNORM;
1120         } else if (count < SG_MAX_QUEUE)
1121                 res |= POLLOUT | POLLWRNORM;
1122         SCSI_LOG_TIMEOUT(3, printk("sg_poll: %s, res=0x%x\n",
1123                                    sdp->disk->disk_name, (int) res));
1124         return res;
1125 }
1126
1127 static int
1128 sg_fasync(int fd, struct file *filp, int mode)
1129 {
1130         int retval;
1131         Sg_device *sdp;
1132         Sg_fd *sfp;
1133
1134         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1135                 return -ENXIO;
1136         SCSI_LOG_TIMEOUT(3, printk("sg_fasync: %s, mode=%d\n",
1137                                    sdp->disk->disk_name, mode));
1138
1139         retval = fasync_helper(fd, filp, mode, &sfp->async_qp);
1140         return (retval < 0) ? retval : 0;
1141 }
1142
1143 /* When startFinish==1 increments page counts for pages other than the
1144    first of scatter gather elements obtained from alloc_pages().
1145    When startFinish==0 decrements ... */
1146 static void
1147 sg_rb_correct4mmap(Sg_scatter_hold * rsv_schp, int startFinish)
1148 {
1149         struct scatterlist *sg = rsv_schp->buffer;
1150         struct page *page;
1151         int k, m;
1152
1153         SCSI_LOG_TIMEOUT(3, printk("sg_rb_correct4mmap: startFinish=%d, scatg=%d\n",
1154                                    startFinish, rsv_schp->k_use_sg));
1155         /* N.B. correction _not_ applied to base page of each allocation */
1156         for (k = 0; k < rsv_schp->k_use_sg; ++k, ++sg) {
1157                 for (m = PAGE_SIZE; m < sg->length; m += PAGE_SIZE) {
1158                         page = sg->page;
1159                         if (startFinish)
1160                                 get_page(page);
1161                         else {
1162                                 if (page_count(page) > 0)
1163                                         __put_page(page);
1164                         }
1165                 }
1166         }
1167 }
1168
1169 static struct page *
1170 sg_vma_nopage(struct vm_area_struct *vma, unsigned long addr, int *type)
1171 {
1172         Sg_fd *sfp;
1173         struct page *page = NOPAGE_SIGBUS;
1174         unsigned long offset, len, sa;
1175         Sg_scatter_hold *rsv_schp;
1176         struct scatterlist *sg;
1177         int k;
1178
1179         if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1180                 return page;
1181         rsv_schp = &sfp->reserve;
1182         offset = addr - vma->vm_start;
1183         if (offset >= rsv_schp->bufflen)
1184                 return page;
1185         SCSI_LOG_TIMEOUT(3, printk("sg_vma_nopage: offset=%lu, scatg=%d\n",
1186                                    offset, rsv_schp->k_use_sg));
1187         sg = rsv_schp->buffer;
1188         sa = vma->vm_start;
1189         for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
1190              ++k, ++sg) {
1191                 len = vma->vm_end - sa;
1192                 len = (len < sg->length) ? len : sg->length;
1193                 if (offset < len) {
1194                         page = sg->page;
1195                         get_page(page); /* increment page count */
1196                         break;
1197                 }
1198                 sa += len;
1199                 offset -= len;
1200         }
1201
1202         if (type)
1203                 *type = VM_FAULT_MINOR;
1204         return page;
1205 }
1206
1207 static struct vm_operations_struct sg_mmap_vm_ops = {
1208         .nopage = sg_vma_nopage,
1209 };
1210
1211 static int
1212 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1213 {
1214         Sg_fd *sfp;
1215         unsigned long req_sz, len, sa;
1216         Sg_scatter_hold *rsv_schp;
1217         int k;
1218         struct scatterlist *sg;
1219
1220         if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1221                 return -ENXIO;
1222         req_sz = vma->vm_end - vma->vm_start;
1223         SCSI_LOG_TIMEOUT(3, printk("sg_mmap starting, vm_start=%p, len=%d\n",
1224                                    (void *) vma->vm_start, (int) req_sz));
1225         if (vma->vm_pgoff)
1226                 return -EINVAL; /* want no offset */
1227         rsv_schp = &sfp->reserve;
1228         if (req_sz > rsv_schp->bufflen)
1229                 return -ENOMEM; /* cannot map more than reserved buffer */
1230
1231         sa = vma->vm_start;
1232         sg = rsv_schp->buffer;
1233         for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
1234              ++k, ++sg) {
1235                 len = vma->vm_end - sa;
1236                 len = (len < sg->length) ? len : sg->length;
1237                 sa += len;
1238         }
1239
1240         if (0 == sfp->mmap_called) {
1241                 sg_rb_correct4mmap(rsv_schp, 1);        /* do only once per fd lifetime */
1242                 sfp->mmap_called = 1;
1243         }
1244         vma->vm_flags |= VM_RESERVED;
1245         vma->vm_private_data = sfp;
1246         vma->vm_ops = &sg_mmap_vm_ops;
1247         return 0;
1248 }
1249
1250 /* This function is a "bottom half" handler that is called by the
1251  * mid level when a command is completed (or has failed). */
1252 static void
1253 sg_cmd_done(void *data, char *sense, int result, int resid)
1254 {
1255         Sg_request *srp = data;
1256         Sg_device *sdp = NULL;
1257         Sg_fd *sfp;
1258         unsigned long iflags;
1259         unsigned int ms;
1260
1261         if (NULL == srp) {
1262                 printk(KERN_ERR "sg_cmd_done: NULL request\n");
1263                 return;
1264         }
1265         sfp = srp->parentfp;
1266         if (sfp)
1267                 sdp = sfp->parentdp;
1268         if ((NULL == sdp) || sdp->detached) {
1269                 printk(KERN_INFO "sg_cmd_done: device detached\n");
1270                 return;
1271         }
1272
1273
1274         SCSI_LOG_TIMEOUT(4, printk("sg_cmd_done: %s, pack_id=%d, res=0x%x\n",
1275                 sdp->disk->disk_name, srp->header.pack_id, result));
1276         srp->header.resid = resid;
1277         ms = jiffies_to_msecs(jiffies);
1278         srp->header.duration = (ms > srp->header.duration) ?
1279                                 (ms - srp->header.duration) : 0;
1280         if (0 != result) {
1281                 struct scsi_sense_hdr sshdr;
1282
1283                 memcpy(srp->sense_b, sense, sizeof (srp->sense_b));
1284                 srp->header.status = 0xff & result;
1285                 srp->header.masked_status = status_byte(result);
1286                 srp->header.msg_status = msg_byte(result);
1287                 srp->header.host_status = host_byte(result);
1288                 srp->header.driver_status = driver_byte(result);
1289                 if ((sdp->sgdebug > 0) &&
1290                     ((CHECK_CONDITION == srp->header.masked_status) ||
1291                      (COMMAND_TERMINATED == srp->header.masked_status)))
1292                         __scsi_print_sense("sg_cmd_done", sense,
1293                                            SCSI_SENSE_BUFFERSIZE);
1294
1295                 /* Following if statement is a patch supplied by Eric Youngdale */
1296                 if (driver_byte(result) != 0
1297                     && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1298                     && !scsi_sense_is_deferred(&sshdr)
1299                     && sshdr.sense_key == UNIT_ATTENTION
1300                     && sdp->device->removable) {
1301                         /* Detected possible disc change. Set the bit - this */
1302                         /* may be used if there are filesystems using this device */
1303                         sdp->device->changed = 1;
1304                 }
1305         }
1306         /* Rely on write phase to clean out srp status values, so no "else" */
1307
1308         if (sfp->closed) {      /* whoops this fd already released, cleanup */
1309                 SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, freeing ...\n"));
1310                 sg_finish_rem_req(srp);
1311                 srp = NULL;
1312                 if (NULL == sfp->headrp) {
1313                         SCSI_LOG_TIMEOUT(1, printk("sg...bh: already closed, final cleanup\n"));
1314                         if (0 == sg_remove_sfp(sdp, sfp)) {     /* device still present */
1315                                 scsi_device_put(sdp->device);
1316                         }
1317                         sfp = NULL;
1318                 }
1319         } else if (srp && srp->orphan) {
1320                 if (sfp->keep_orphan)
1321                         srp->sg_io_owned = 0;
1322                 else {
1323                         sg_finish_rem_req(srp);
1324                         srp = NULL;
1325                 }
1326         }
1327         if (sfp && srp) {
1328                 /* Now wake up any sg_read() that is waiting for this packet. */
1329                 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1330                 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1331                 srp->done = 1;
1332                 wake_up_interruptible(&sfp->read_wait);
1333                 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1334         }
1335 }
1336
1337 static struct file_operations sg_fops = {
1338         .owner = THIS_MODULE,
1339         .read = sg_read,
1340         .write = sg_write,
1341         .poll = sg_poll,
1342         .ioctl = sg_ioctl,
1343 #ifdef CONFIG_COMPAT
1344         .compat_ioctl = sg_compat_ioctl,
1345 #endif
1346         .open = sg_open,
1347         .mmap = sg_mmap,
1348         .release = sg_release,
1349         .fasync = sg_fasync,
1350 };
1351
1352 static struct class *sg_sysfs_class;
1353
1354 static int sg_sysfs_valid = 0;
1355
1356 static int sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1357 {
1358         struct request_queue *q = scsidp->request_queue;
1359         Sg_device *sdp;
1360         unsigned long iflags;
1361         void *old_sg_dev_arr = NULL;
1362         int k, error;
1363
1364         sdp = kmalloc(sizeof(Sg_device), GFP_KERNEL);
1365         if (!sdp) {
1366                 printk(KERN_WARNING "kmalloc Sg_device failure\n");
1367                 return -ENOMEM;
1368         }
1369
1370         write_lock_irqsave(&sg_dev_arr_lock, iflags);
1371         if (unlikely(sg_nr_dev >= sg_dev_max)) {        /* try to resize */
1372                 Sg_device **tmp_da;
1373                 int tmp_dev_max = sg_nr_dev + SG_DEV_ARR_LUMP;
1374                 write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1375
1376                 tmp_da = kmalloc(tmp_dev_max * sizeof(Sg_device *), GFP_KERNEL);
1377                 if (unlikely(!tmp_da))
1378                         goto expand_failed;
1379
1380                 write_lock_irqsave(&sg_dev_arr_lock, iflags);
1381                 memset(tmp_da, 0, tmp_dev_max * sizeof(Sg_device *));
1382                 memcpy(tmp_da, sg_dev_arr, sg_dev_max * sizeof(Sg_device *));
1383                 old_sg_dev_arr = sg_dev_arr;
1384                 sg_dev_arr = tmp_da;
1385                 sg_dev_max = tmp_dev_max;
1386         }
1387
1388         for (k = 0; k < sg_dev_max; k++)
1389                 if (!sg_dev_arr[k])
1390                         break;
1391         if (unlikely(k >= SG_MAX_DEVS))
1392                 goto overflow;
1393
1394         memset(sdp, 0, sizeof(*sdp));
1395         SCSI_LOG_TIMEOUT(3, printk("sg_alloc: dev=%d \n", k));
1396         sprintf(disk->disk_name, "sg%d", k);
1397         disk->first_minor = k;
1398         sdp->disk = disk;
1399         sdp->device = scsidp;
1400         init_waitqueue_head(&sdp->o_excl_wait);
1401         sdp->sg_tablesize = min(q->max_hw_segments, q->max_phys_segments);
1402
1403         sg_nr_dev++;
1404         sg_dev_arr[k] = sdp;
1405         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1406         error = k;
1407
1408  out:
1409         if (error < 0)
1410                 kfree(sdp);
1411         kfree(old_sg_dev_arr);
1412         return error;
1413
1414  expand_failed:
1415         printk(KERN_WARNING "sg_alloc: device array cannot be resized\n");
1416         error = -ENOMEM;
1417         goto out;
1418
1419  overflow:
1420         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1421         sdev_printk(KERN_WARNING, scsidp,
1422                     "Unable to attach sg device type=%d, minor "
1423                     "number exceeds %d\n", scsidp->type, SG_MAX_DEVS - 1);
1424         error = -ENODEV;
1425         goto out;
1426 }
1427
1428 static int
1429 sg_add(struct class_device *cl_dev, struct class_interface *cl_intf)
1430 {
1431         struct scsi_device *scsidp = to_scsi_device(cl_dev->dev);
1432         struct gendisk *disk;
1433         Sg_device *sdp = NULL;
1434         struct cdev * cdev = NULL;
1435         int error, k;
1436
1437         disk = alloc_disk(1);
1438         if (!disk) {
1439                 printk(KERN_WARNING "alloc_disk failed\n");
1440                 return -ENOMEM;
1441         }
1442         disk->major = SCSI_GENERIC_MAJOR;
1443
1444         error = -ENOMEM;
1445         cdev = cdev_alloc();
1446         if (!cdev) {
1447                 printk(KERN_WARNING "cdev_alloc failed\n");
1448                 goto out;
1449         }
1450         cdev->owner = THIS_MODULE;
1451         cdev->ops = &sg_fops;
1452
1453         error = sg_alloc(disk, scsidp);
1454         if (error < 0) {
1455                 printk(KERN_WARNING "sg_alloc failed\n");
1456                 goto out;
1457         }
1458         k = error;
1459         sdp = sg_dev_arr[k];
1460
1461         devfs_mk_cdev(MKDEV(SCSI_GENERIC_MAJOR, k),
1462                         S_IFCHR | S_IRUSR | S_IWUSR | S_IRGRP,
1463                         "%s/generic", scsidp->devfs_name);
1464         error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, k), 1);
1465         if (error) {
1466                 devfs_remove("%s/generic", scsidp->devfs_name);
1467                 goto out;
1468         }
1469         sdp->cdev = cdev;
1470         if (sg_sysfs_valid) {
1471                 struct class_device * sg_class_member;
1472
1473                 sg_class_member = class_device_create(sg_sysfs_class, NULL,
1474                                 MKDEV(SCSI_GENERIC_MAJOR, k),
1475                                 cl_dev->dev, "%s",
1476                                 disk->disk_name);
1477                 if (IS_ERR(sg_class_member))
1478                         printk(KERN_WARNING "sg_add: "
1479                                 "class_device_create failed\n");
1480                 class_set_devdata(sg_class_member, sdp);
1481                 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1482                                           &sg_class_member->kobj, "generic");
1483                 if (error)
1484                         printk(KERN_ERR "sg_add: unable to make symlink "
1485                                         "'generic' back to sg%d\n", k);
1486         } else
1487                 printk(KERN_WARNING "sg_add: sg_sys INvalid\n");
1488
1489         sdev_printk(KERN_NOTICE, scsidp,
1490                     "Attached scsi generic sg%d type %d\n", k,scsidp->type);
1491
1492         return 0;
1493
1494 out:
1495         put_disk(disk);
1496         if (cdev)
1497                 cdev_del(cdev);
1498         return error;
1499 }
1500
1501 static void
1502 sg_remove(struct class_device *cl_dev, struct class_interface *cl_intf)
1503 {
1504         struct scsi_device *scsidp = to_scsi_device(cl_dev->dev);
1505         Sg_device *sdp = NULL;
1506         unsigned long iflags;
1507         Sg_fd *sfp;
1508         Sg_fd *tsfp;
1509         Sg_request *srp;
1510         Sg_request *tsrp;
1511         int k, delay;
1512
1513         if (NULL == sg_dev_arr)
1514                 return;
1515         delay = 0;
1516         write_lock_irqsave(&sg_dev_arr_lock, iflags);
1517         for (k = 0; k < sg_dev_max; k++) {
1518                 sdp = sg_dev_arr[k];
1519                 if ((NULL == sdp) || (sdp->device != scsidp))
1520                         continue;       /* dirty but lowers nesting */
1521                 if (sdp->headfp) {
1522                         sdp->detached = 1;
1523                         for (sfp = sdp->headfp; sfp; sfp = tsfp) {
1524                                 tsfp = sfp->nextfp;
1525                                 for (srp = sfp->headrp; srp; srp = tsrp) {
1526                                         tsrp = srp->nextrp;
1527                                         if (sfp->closed || (0 == sg_srp_done(srp, sfp)))
1528                                                 sg_finish_rem_req(srp);
1529                                 }
1530                                 if (sfp->closed) {
1531                                         scsi_device_put(sdp->device);
1532                                         __sg_remove_sfp(sdp, sfp);
1533                                 } else {
1534                                         delay = 1;
1535                                         wake_up_interruptible(&sfp->read_wait);
1536                                         kill_fasync(&sfp->async_qp, SIGPOLL,
1537                                                     POLL_HUP);
1538                                 }
1539                         }
1540                         SCSI_LOG_TIMEOUT(3, printk("sg_detach: dev=%d, dirty\n", k));
1541                         if (NULL == sdp->headfp) {
1542                                 sg_dev_arr[k] = NULL;
1543                         }
1544                 } else {        /* nothing active, simple case */
1545                         SCSI_LOG_TIMEOUT(3, printk("sg_detach: dev=%d\n", k));
1546                         sg_dev_arr[k] = NULL;
1547                 }
1548                 sg_nr_dev--;
1549                 break;
1550         }
1551         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1552
1553         if (sdp) {
1554                 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1555                 class_device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, k));
1556                 cdev_del(sdp->cdev);
1557                 sdp->cdev = NULL;
1558                 devfs_remove("%s/generic", scsidp->devfs_name);
1559                 put_disk(sdp->disk);
1560                 sdp->disk = NULL;
1561                 if (NULL == sdp->headfp)
1562                         kfree((char *) sdp);
1563         }
1564
1565         if (delay)
1566                 msleep(10);     /* dirty detach so delay device destruction */
1567 }
1568
1569 /* Set 'perm' (4th argument) to 0 to disable module_param's definition
1570  * of sysfs parameters (which module_param doesn't yet support).
1571  * Sysfs parameters defined explicitly below.
1572  */
1573 module_param_named(def_reserved_size, def_reserved_size, int, S_IRUGO);
1574 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1575
1576 MODULE_AUTHOR("Douglas Gilbert");
1577 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1578 MODULE_LICENSE("GPL");
1579 MODULE_VERSION(SG_VERSION_STR);
1580
1581 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1582 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1583
1584 static int __init
1585 init_sg(void)
1586 {
1587         int rc;
1588
1589         if (def_reserved_size >= 0)
1590                 sg_big_buff = def_reserved_size;
1591
1592         rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1593                                     SG_MAX_DEVS, "sg");
1594         if (rc)
1595                 return rc;
1596         sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1597         if ( IS_ERR(sg_sysfs_class) ) {
1598                 rc = PTR_ERR(sg_sysfs_class);
1599                 goto err_out;
1600         }
1601         sg_sysfs_valid = 1;
1602         rc = scsi_register_interface(&sg_interface);
1603         if (0 == rc) {
1604 #ifdef CONFIG_SCSI_PROC_FS
1605                 sg_proc_init();
1606 #endif                          /* CONFIG_SCSI_PROC_FS */
1607                 return 0;
1608         }
1609         class_destroy(sg_sysfs_class);
1610 err_out:
1611         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1612         return rc;
1613 }
1614
1615 static void __exit
1616 exit_sg(void)
1617 {
1618 #ifdef CONFIG_SCSI_PROC_FS
1619         sg_proc_cleanup();
1620 #endif                          /* CONFIG_SCSI_PROC_FS */
1621         scsi_unregister_interface(&sg_interface);
1622         class_destroy(sg_sysfs_class);
1623         sg_sysfs_valid = 0;
1624         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1625                                  SG_MAX_DEVS);
1626         kfree((char *)sg_dev_arr);
1627         sg_dev_arr = NULL;
1628         sg_dev_max = 0;
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         unsigned int 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         schp->sglist_len = sg_bufflen;
1696         return tablesize;       /* number of scat_gath elements allocated */
1697 }
1698
1699 #ifdef SG_ALLOW_DIO_CODE
1700 /* vvvvvvvv  following code borrowed from st driver's direct IO vvvvvvvvv */
1701         /* TODO: hopefully we can use the generic block layer code */
1702
1703 /* Pin down user pages and put them into a scatter gather list. Returns <= 0 if
1704    - mapping of all pages not successful
1705    (i.e., either completely successful or fails)
1706 */
1707 static int
1708 st_map_user_pages(struct scatterlist *sgl, const unsigned int max_pages,
1709                   unsigned long uaddr, size_t count, int rw)
1710 {
1711         unsigned long end = (uaddr + count + PAGE_SIZE - 1) >> PAGE_SHIFT;
1712         unsigned long start = uaddr >> PAGE_SHIFT;
1713         const int nr_pages = end - start;
1714         int res, i, j;
1715         struct page **pages;
1716
1717         /* User attempted Overflow! */
1718         if ((uaddr + count) < uaddr)
1719                 return -EINVAL;
1720
1721         /* Too big */
1722         if (nr_pages > max_pages)
1723                 return -ENOMEM;
1724
1725         /* Hmm? */
1726         if (count == 0)
1727                 return 0;
1728
1729         if ((pages = kmalloc(max_pages * sizeof(*pages), GFP_ATOMIC)) == NULL)
1730                 return -ENOMEM;
1731
1732         /* Try to fault in all of the necessary pages */
1733         down_read(&current->mm->mmap_sem);
1734         /* rw==READ means read from drive, write into memory area */
1735         res = get_user_pages(
1736                 current,
1737                 current->mm,
1738                 uaddr,
1739                 nr_pages,
1740                 rw == READ,
1741                 0, /* don't force */
1742                 pages,
1743                 NULL);
1744         up_read(&current->mm->mmap_sem);
1745
1746         /* Errors and no page mapped should return here */
1747         if (res < nr_pages)
1748                 goto out_unmap;
1749
1750         for (i=0; i < nr_pages; i++) {
1751                 /* FIXME: flush superflous for rw==READ,
1752                  * probably wrong function for rw==WRITE
1753                  */
1754                 flush_dcache_page(pages[i]);
1755                 /* ?? Is locking needed? I don't think so */
1756                 /* if (TestSetPageLocked(pages[i]))
1757                    goto out_unlock; */
1758         }
1759
1760         sgl[0].page = pages[0];
1761         sgl[0].offset = 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                         sgl[i].page = pages[i];
1767                         sgl[i].length = count < PAGE_SIZE ? count : PAGE_SIZE;
1768                         count -= PAGE_SIZE;
1769                 }
1770         }
1771         else {
1772                 sgl[0].length = count;
1773         }
1774
1775         kfree(pages);
1776         return nr_pages;
1777
1778  out_unmap:
1779         if (res > 0) {
1780                 for (j=0; j < res; j++)
1781                         page_cache_release(pages[j]);
1782                 res = 0;
1783         }
1784         kfree(pages);
1785         return res;
1786 }
1787
1788
1789 /* And unmap them... */
1790 static int
1791 st_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_pages,
1792                     int dirtied)
1793 {
1794         int i;
1795
1796         for (i=0; i < nr_pages; i++) {
1797                 struct page *page = sgl[i].page;
1798
1799                 if (dirtied)
1800                         SetPageDirty(page);
1801                 /* unlock_page(page); */
1802                 /* FIXME: cache flush missing for rw==READ
1803                  * FIXME: call the correct reference counting function
1804                  */
1805                 page_cache_release(page);
1806         }
1807
1808         return 0;
1809 }
1810
1811 /* ^^^^^^^^  above code borrowed from st driver's direct IO ^^^^^^^^^ */
1812 #endif
1813
1814
1815 /* Returns: -ve -> error, 0 -> done, 1 -> try indirect */
1816 static int
1817 sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len)
1818 {
1819 #ifdef SG_ALLOW_DIO_CODE
1820         sg_io_hdr_t *hp = &srp->header;
1821         Sg_scatter_hold *schp = &srp->data;
1822         int sg_tablesize = sfp->parentdp->sg_tablesize;
1823         int mx_sc_elems, res;
1824         struct scsi_device *sdev = sfp->parentdp->device;
1825
1826         if (((unsigned long)hp->dxferp &
1827                         queue_dma_alignment(sdev->request_queue)) != 0)
1828                 return 1;
1829
1830         mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1831         if (mx_sc_elems <= 0) {
1832                 return 1;
1833         }
1834         res = st_map_user_pages(schp->buffer, mx_sc_elems,
1835                                 (unsigned long)hp->dxferp, dxfer_len,
1836                                 (SG_DXFER_TO_DEV == hp->dxfer_direction) ? 1 : 0);
1837         if (res <= 0)
1838                 return 1;
1839         schp->k_use_sg = res;
1840         schp->dio_in_use = 1;
1841         hp->info |= SG_INFO_DIRECT_IO;
1842         return 0;
1843 #else
1844         return 1;
1845 #endif
1846 }
1847
1848 static int
1849 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1850 {
1851         struct scatterlist *sg;
1852         int ret_sz = 0, k, rem_sz, num, mx_sc_elems;
1853         int sg_tablesize = sfp->parentdp->sg_tablesize;
1854         int blk_size = buff_size;
1855         struct page *p = NULL;
1856
1857         if ((blk_size < 0) || (!sfp))
1858                 return -EFAULT;
1859         if (0 == blk_size)
1860                 ++blk_size;     /* don't know why */
1861 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1862         blk_size = (blk_size + SG_SECTOR_MSK) & (~SG_SECTOR_MSK);
1863         SCSI_LOG_TIMEOUT(4, printk("sg_build_indirect: buff_size=%d, blk_size=%d\n",
1864                                    buff_size, blk_size));
1865
1866         /* N.B. ret_sz carried into this block ... */
1867         mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1868         if (mx_sc_elems < 0)
1869                 return mx_sc_elems;     /* most likely -ENOMEM */
1870
1871         for (k = 0, sg = schp->buffer, rem_sz = blk_size;
1872              (rem_sz > 0) && (k < mx_sc_elems);
1873              ++k, rem_sz -= ret_sz, ++sg) {
1874
1875                 num = (rem_sz > SG_SCATTER_SZ) ? SG_SCATTER_SZ : rem_sz;
1876                 p = sg_page_malloc(num, sfp->low_dma, &ret_sz);
1877                 if (!p)
1878                         return -ENOMEM;
1879
1880                 sg->page = p;
1881                 sg->length = ret_sz;
1882
1883                 SCSI_LOG_TIMEOUT(5, printk("sg_build_build: k=%d, a=0x%p, len=%d\n",
1884                                   k, p, ret_sz));
1885         }               /* end of for loop */
1886
1887         schp->k_use_sg = k;
1888         SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, rem_sz=%d\n", k, rem_sz));
1889
1890         schp->bufflen = blk_size;
1891         if (rem_sz > 0) /* must have failed */
1892                 return -ENOMEM;
1893
1894         return 0;
1895 }
1896
1897 static int
1898 sg_write_xfer(Sg_request * srp)
1899 {
1900         sg_io_hdr_t *hp = &srp->header;
1901         Sg_scatter_hold *schp = &srp->data;
1902         struct scatterlist *sg = schp->buffer;
1903         int num_xfer = 0;
1904         int j, k, onum, usglen, ksglen, res;
1905         int iovec_count = (int) hp->iovec_count;
1906         int dxfer_dir = hp->dxfer_direction;
1907         unsigned char *p;
1908         unsigned char __user *up;
1909         int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
1910
1911         if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_TO_DEV == dxfer_dir) ||
1912             (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
1913                 num_xfer = (int) (new_interface ? hp->dxfer_len : hp->flags);
1914                 if (schp->bufflen < num_xfer)
1915                         num_xfer = schp->bufflen;
1916         }
1917         if ((num_xfer <= 0) || (schp->dio_in_use) ||
1918             (new_interface
1919              && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
1920                 return 0;
1921
1922         SCSI_LOG_TIMEOUT(4, printk("sg_write_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
1923                           num_xfer, iovec_count, schp->k_use_sg));
1924         if (iovec_count) {
1925                 onum = iovec_count;
1926                 if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum))
1927                         return -EFAULT;
1928         } else
1929                 onum = 1;
1930
1931         ksglen = sg->length;
1932         p = page_address(sg->page);
1933         for (j = 0, k = 0; j < onum; ++j) {
1934                 res = sg_u_iovec(hp, iovec_count, j, 1, &usglen, &up);
1935                 if (res)
1936                         return res;
1937
1938                 for (; p; ++sg, ksglen = sg->length,
1939                      p = page_address(sg->page)) {
1940                         if (usglen <= 0)
1941                                 break;
1942                         if (ksglen > usglen) {
1943                                 if (usglen >= num_xfer) {
1944                                         if (__copy_from_user(p, up, num_xfer))
1945                                                 return -EFAULT;
1946                                         return 0;
1947                                 }
1948                                 if (__copy_from_user(p, up, usglen))
1949                                         return -EFAULT;
1950                                 p += usglen;
1951                                 ksglen -= usglen;
1952                                 break;
1953                         } else {
1954                                 if (ksglen >= num_xfer) {
1955                                         if (__copy_from_user(p, up, num_xfer))
1956                                                 return -EFAULT;
1957                                         return 0;
1958                                 }
1959                                 if (__copy_from_user(p, up, ksglen))
1960                                         return -EFAULT;
1961                                 up += ksglen;
1962                                 usglen -= ksglen;
1963                         }
1964                         ++k;
1965                         if (k >= schp->k_use_sg)
1966                                 return 0;
1967                 }
1968         }
1969
1970         return 0;
1971 }
1972
1973 static int
1974 sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
1975            int wr_xf, int *countp, unsigned char __user **up)
1976 {
1977         int num_xfer = (int) hp->dxfer_len;
1978         unsigned char __user *p = hp->dxferp;
1979         int count;
1980
1981         if (0 == sg_num) {
1982                 if (wr_xf && ('\0' == hp->interface_id))
1983                         count = (int) hp->flags;        /* holds "old" input_size */
1984                 else
1985                         count = num_xfer;
1986         } else {
1987                 sg_iovec_t iovec;
1988                 if (__copy_from_user(&iovec, p + ind*SZ_SG_IOVEC, SZ_SG_IOVEC))
1989                         return -EFAULT;
1990                 p = iovec.iov_base;
1991                 count = (int) iovec.iov_len;
1992         }
1993         if (!access_ok(wr_xf ? VERIFY_READ : VERIFY_WRITE, p, count))
1994                 return -EFAULT;
1995         if (up)
1996                 *up = p;
1997         if (countp)
1998                 *countp = count;
1999         return 0;
2000 }
2001
2002 static void
2003 sg_remove_scat(Sg_scatter_hold * schp)
2004 {
2005         SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
2006         if (schp->buffer && (schp->sglist_len > 0)) {
2007                 struct scatterlist *sg = schp->buffer;
2008
2009                 if (schp->dio_in_use) {
2010 #ifdef SG_ALLOW_DIO_CODE
2011                         st_unmap_user_pages(sg, schp->k_use_sg, TRUE);
2012 #endif
2013                 } else {
2014                         int k;
2015
2016                         for (k = 0; (k < schp->k_use_sg) && sg->page;
2017                              ++k, ++sg) {
2018                                 SCSI_LOG_TIMEOUT(5, printk(
2019                                     "sg_remove_scat: k=%d, a=0x%p, len=%d\n",
2020                                     k, sg->page, sg->length));
2021                                 sg_page_free(sg->page, sg->length);
2022                         }
2023                 }
2024                 kfree(schp->buffer);
2025         }
2026         memset(schp, 0, sizeof (*schp));
2027 }
2028
2029 static int
2030 sg_read_xfer(Sg_request * srp)
2031 {
2032         sg_io_hdr_t *hp = &srp->header;
2033         Sg_scatter_hold *schp = &srp->data;
2034         struct scatterlist *sg = schp->buffer;
2035         int num_xfer = 0;
2036         int j, k, onum, usglen, ksglen, res;
2037         int iovec_count = (int) hp->iovec_count;
2038         int dxfer_dir = hp->dxfer_direction;
2039         unsigned char *p;
2040         unsigned char __user *up;
2041         int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
2042
2043         if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_FROM_DEV == dxfer_dir)
2044             || (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
2045                 num_xfer = hp->dxfer_len;
2046                 if (schp->bufflen < num_xfer)
2047                         num_xfer = schp->bufflen;
2048         }
2049         if ((num_xfer <= 0) || (schp->dio_in_use) ||
2050             (new_interface
2051              && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
2052                 return 0;
2053
2054         SCSI_LOG_TIMEOUT(4, printk("sg_read_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
2055                           num_xfer, iovec_count, schp->k_use_sg));
2056         if (iovec_count) {
2057                 onum = iovec_count;
2058                 if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum))
2059                         return -EFAULT;
2060         } else
2061                 onum = 1;
2062
2063         p = page_address(sg->page);
2064         ksglen = sg->length;
2065         for (j = 0, k = 0; j < onum; ++j) {
2066                 res = sg_u_iovec(hp, iovec_count, j, 0, &usglen, &up);
2067                 if (res)
2068                         return res;
2069
2070                 for (; p; ++sg, ksglen = sg->length,
2071                      p = page_address(sg->page)) {
2072                         if (usglen <= 0)
2073                                 break;
2074                         if (ksglen > usglen) {
2075                                 if (usglen >= num_xfer) {
2076                                         if (__copy_to_user(up, p, num_xfer))
2077                                                 return -EFAULT;
2078                                         return 0;
2079                                 }
2080                                 if (__copy_to_user(up, p, usglen))
2081                                         return -EFAULT;
2082                                 p += usglen;
2083                                 ksglen -= usglen;
2084                                 break;
2085                         } else {
2086                                 if (ksglen >= num_xfer) {
2087                                         if (__copy_to_user(up, p, num_xfer))
2088                                                 return -EFAULT;
2089                                         return 0;
2090                                 }
2091                                 if (__copy_to_user(up, p, ksglen))
2092                                         return -EFAULT;
2093                                 up += ksglen;
2094                                 usglen -= ksglen;
2095                         }
2096                         ++k;
2097                         if (k >= schp->k_use_sg)
2098                                 return 0;
2099                 }
2100         }
2101
2102         return 0;
2103 }
2104
2105 static int
2106 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
2107 {
2108         Sg_scatter_hold *schp = &srp->data;
2109         struct scatterlist *sg = schp->buffer;
2110         int k, num;
2111
2112         SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n",
2113                                    num_read_xfer));
2114         if ((!outp) || (num_read_xfer <= 0))
2115                 return 0;
2116
2117         for (k = 0; (k < schp->k_use_sg) && sg->page; ++k, ++sg) {
2118                 num = sg->length;
2119                 if (num > num_read_xfer) {
2120                         if (__copy_to_user(outp, page_address(sg->page),
2121                                            num_read_xfer))
2122                                 return -EFAULT;
2123                         break;
2124                 } else {
2125                         if (__copy_to_user(outp, page_address(sg->page),
2126                                            num))
2127                                 return -EFAULT;
2128                         num_read_xfer -= num;
2129                         if (num_read_xfer <= 0)
2130                                 break;
2131                         outp += num;
2132                 }
2133         }
2134
2135         return 0;
2136 }
2137
2138 static void
2139 sg_build_reserve(Sg_fd * sfp, int req_size)
2140 {
2141         Sg_scatter_hold *schp = &sfp->reserve;
2142
2143         SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
2144         do {
2145                 if (req_size < PAGE_SIZE)
2146                         req_size = PAGE_SIZE;
2147                 if (0 == sg_build_indirect(schp, sfp, req_size))
2148                         return;
2149                 else
2150                         sg_remove_scat(schp);
2151                 req_size >>= 1; /* divide by 2 */
2152         } while (req_size > (PAGE_SIZE / 2));
2153 }
2154
2155 static void
2156 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2157 {
2158         Sg_scatter_hold *req_schp = &srp->data;
2159         Sg_scatter_hold *rsv_schp = &sfp->reserve;
2160         struct scatterlist *sg = rsv_schp->buffer;
2161         int k, num, rem;
2162
2163         srp->res_used = 1;
2164         SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
2165         rem = size = (size + 1) & (~1); /* round to even for aha1542 */
2166
2167         for (k = 0; k < rsv_schp->k_use_sg; ++k, ++sg) {
2168                 num = sg->length;
2169                 if (rem <= num) {
2170                         sfp->save_scat_len = num;
2171                         sg->length = rem;
2172                         req_schp->k_use_sg = k + 1;
2173                         req_schp->sglist_len = rsv_schp->sglist_len;
2174                         req_schp->buffer = rsv_schp->buffer;
2175
2176                         req_schp->bufflen = size;
2177                         req_schp->b_malloc_len = rsv_schp->b_malloc_len;
2178                         break;
2179                 } else
2180                         rem -= num;
2181         }
2182
2183         if (k >= rsv_schp->k_use_sg)
2184                 SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
2185 }
2186
2187 static void
2188 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2189 {
2190         Sg_scatter_hold *req_schp = &srp->data;
2191         Sg_scatter_hold *rsv_schp = &sfp->reserve;
2192
2193         SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->k_use_sg=%d\n",
2194                                    (int) req_schp->k_use_sg));
2195         if ((rsv_schp->k_use_sg > 0) && (req_schp->k_use_sg > 0)) {
2196                 struct scatterlist *sg = rsv_schp->buffer;
2197
2198                 if (sfp->save_scat_len > 0)
2199                         (sg + (req_schp->k_use_sg - 1))->length =
2200                             (unsigned) sfp->save_scat_len;
2201                 else
2202                         SCSI_LOG_TIMEOUT(1, printk ("sg_unlink_reserve: BAD save_scat_len\n"));
2203         }
2204         req_schp->k_use_sg = 0;
2205         req_schp->bufflen = 0;
2206         req_schp->buffer = NULL;
2207         req_schp->sglist_len = 0;
2208         sfp->save_scat_len = 0;
2209         srp->res_used = 0;
2210 }
2211
2212 static Sg_request *
2213 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2214 {
2215         Sg_request *resp;
2216         unsigned long iflags;
2217
2218         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2219         for (resp = sfp->headrp; resp; resp = resp->nextrp) {
2220                 /* look for requests that are ready + not SG_IO owned */
2221                 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2222                     ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2223                         resp->done = 2; /* guard against other readers */
2224                         break;
2225                 }
2226         }
2227         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2228         return resp;
2229 }
2230
2231 #ifdef CONFIG_SCSI_PROC_FS
2232 static Sg_request *
2233 sg_get_nth_request(Sg_fd * sfp, int nth)
2234 {
2235         Sg_request *resp;
2236         unsigned long iflags;
2237         int k;
2238
2239         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2240         for (k = 0, resp = sfp->headrp; resp && (k < nth);
2241              ++k, resp = resp->nextrp) ;
2242         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2243         return resp;
2244 }
2245 #endif
2246
2247 /* always adds to end of list */
2248 static Sg_request *
2249 sg_add_request(Sg_fd * sfp)
2250 {
2251         int k;
2252         unsigned long iflags;
2253         Sg_request *resp;
2254         Sg_request *rp = sfp->req_arr;
2255
2256         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2257         resp = sfp->headrp;
2258         if (!resp) {
2259                 memset(rp, 0, sizeof (Sg_request));
2260                 rp->parentfp = sfp;
2261                 resp = rp;
2262                 sfp->headrp = resp;
2263         } else {
2264                 if (0 == sfp->cmd_q)
2265                         resp = NULL;    /* command queuing disallowed */
2266                 else {
2267                         for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2268                                 if (!rp->parentfp)
2269                                         break;
2270                         }
2271                         if (k < SG_MAX_QUEUE) {
2272                                 memset(rp, 0, sizeof (Sg_request));
2273                                 rp->parentfp = sfp;
2274                                 while (resp->nextrp)
2275                                         resp = resp->nextrp;
2276                                 resp->nextrp = rp;
2277                                 resp = rp;
2278                         } else
2279                                 resp = NULL;
2280                 }
2281         }
2282         if (resp) {
2283                 resp->nextrp = NULL;
2284                 resp->header.duration = jiffies_to_msecs(jiffies);
2285         }
2286         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2287         return resp;
2288 }
2289
2290 /* Return of 1 for found; 0 for not found */
2291 static int
2292 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2293 {
2294         Sg_request *prev_rp;
2295         Sg_request *rp;
2296         unsigned long iflags;
2297         int res = 0;
2298
2299         if ((!sfp) || (!srp) || (!sfp->headrp))
2300                 return res;
2301         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2302         prev_rp = sfp->headrp;
2303         if (srp == prev_rp) {
2304                 sfp->headrp = prev_rp->nextrp;
2305                 prev_rp->parentfp = NULL;
2306                 res = 1;
2307         } else {
2308                 while ((rp = prev_rp->nextrp)) {
2309                         if (srp == rp) {
2310                                 prev_rp->nextrp = rp->nextrp;
2311                                 rp->parentfp = NULL;
2312                                 res = 1;
2313                                 break;
2314                         }
2315                         prev_rp = rp;
2316                 }
2317         }
2318         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2319         return res;
2320 }
2321
2322 #ifdef CONFIG_SCSI_PROC_FS
2323 static Sg_fd *
2324 sg_get_nth_sfp(Sg_device * sdp, int nth)
2325 {
2326         Sg_fd *resp;
2327         unsigned long iflags;
2328         int k;
2329
2330         read_lock_irqsave(&sg_dev_arr_lock, iflags);
2331         for (k = 0, resp = sdp->headfp; resp && (k < nth);
2332              ++k, resp = resp->nextfp) ;
2333         read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2334         return resp;
2335 }
2336 #endif
2337
2338 static Sg_fd *
2339 sg_add_sfp(Sg_device * sdp, int dev)
2340 {
2341         Sg_fd *sfp;
2342         unsigned long iflags;
2343
2344         sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2345         if (!sfp)
2346                 return NULL;
2347
2348         init_waitqueue_head(&sfp->read_wait);
2349         rwlock_init(&sfp->rq_list_lock);
2350
2351         sfp->timeout = SG_DEFAULT_TIMEOUT;
2352         sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2353         sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2354         sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
2355             sdp->device->host->unchecked_isa_dma : 1;
2356         sfp->cmd_q = SG_DEF_COMMAND_Q;
2357         sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2358         sfp->parentdp = sdp;
2359         write_lock_irqsave(&sg_dev_arr_lock, iflags);
2360         if (!sdp->headfp)
2361                 sdp->headfp = sfp;
2362         else {                  /* add to tail of existing list */
2363                 Sg_fd *pfp = sdp->headfp;
2364                 while (pfp->nextfp)
2365                         pfp = pfp->nextfp;
2366                 pfp->nextfp = sfp;
2367         }
2368         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2369         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));
2370         sg_build_reserve(sfp, sg_big_buff);
2371         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp:   bufflen=%d, k_use_sg=%d\n",
2372                            sfp->reserve.bufflen, sfp->reserve.k_use_sg));
2373         return sfp;
2374 }
2375
2376 static void
2377 __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2378 {
2379         Sg_fd *fp;
2380         Sg_fd *prev_fp;
2381
2382         prev_fp = sdp->headfp;
2383         if (sfp == prev_fp)
2384                 sdp->headfp = prev_fp->nextfp;
2385         else {
2386                 while ((fp = prev_fp->nextfp)) {
2387                         if (sfp == fp) {
2388                                 prev_fp->nextfp = fp->nextfp;
2389                                 break;
2390                         }
2391                         prev_fp = fp;
2392                 }
2393         }
2394         if (sfp->reserve.bufflen > 0) {
2395                 SCSI_LOG_TIMEOUT(6,
2396                         printk("__sg_remove_sfp:    bufflen=%d, k_use_sg=%d\n",
2397                         (int) sfp->reserve.bufflen, (int) sfp->reserve.k_use_sg));
2398                 if (sfp->mmap_called)
2399                         sg_rb_correct4mmap(&sfp->reserve, 0);   /* undo correction */
2400                 sg_remove_scat(&sfp->reserve);
2401         }
2402         sfp->parentdp = NULL;
2403         SCSI_LOG_TIMEOUT(6, printk("__sg_remove_sfp:    sfp=0x%p\n", sfp));
2404         kfree(sfp);
2405 }
2406
2407 /* Returns 0 in normal case, 1 when detached and sdp object removed */
2408 static int
2409 sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2410 {
2411         Sg_request *srp;
2412         Sg_request *tsrp;
2413         int dirty = 0;
2414         int res = 0;
2415
2416         for (srp = sfp->headrp; srp; srp = tsrp) {
2417                 tsrp = srp->nextrp;
2418                 if (sg_srp_done(srp, sfp))
2419                         sg_finish_rem_req(srp);
2420                 else
2421                         ++dirty;
2422         }
2423         if (0 == dirty) {
2424                 unsigned long iflags;
2425
2426                 write_lock_irqsave(&sg_dev_arr_lock, iflags);
2427                 __sg_remove_sfp(sdp, sfp);
2428                 if (sdp->detached && (NULL == sdp->headfp)) {
2429                         int k, maxd;
2430
2431                         maxd = sg_dev_max;
2432                         for (k = 0; k < maxd; ++k) {
2433                                 if (sdp == sg_dev_arr[k])
2434                                         break;
2435                         }
2436                         if (k < maxd)
2437                                 sg_dev_arr[k] = NULL;
2438                         kfree((char *) sdp);
2439                         res = 1;
2440                 }
2441                 write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2442         } else {
2443                 /* MOD_INC's to inhibit unloading sg and associated adapter driver */
2444                 /* only bump the access_count if we actually succeeded in
2445                  * throwing another counter on the host module */
2446                 scsi_device_get(sdp->device);   /* XXX: retval ignored? */
2447                 sfp->closed = 1;        /* flag dirty state on this fd */
2448                 SCSI_LOG_TIMEOUT(1, printk("sg_remove_sfp: worrisome, %d writes pending\n",
2449                                   dirty));
2450         }
2451         return res;
2452 }
2453
2454 static int
2455 sg_res_in_use(Sg_fd * sfp)
2456 {
2457         const Sg_request *srp;
2458         unsigned long iflags;
2459
2460         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2461         for (srp = sfp->headrp; srp; srp = srp->nextrp)
2462                 if (srp->res_used)
2463                         break;
2464         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2465         return srp ? 1 : 0;
2466 }
2467
2468 /* If retSzp==NULL want exact size or fail */
2469 static struct page *
2470 sg_page_malloc(int rqSz, int lowDma, int *retSzp)
2471 {
2472         struct page *resp = NULL;
2473         gfp_t page_mask;
2474         int order, a_size;
2475         int resSz = rqSz;
2476
2477         if (rqSz <= 0)
2478                 return resp;
2479
2480         if (lowDma)
2481                 page_mask = GFP_ATOMIC | GFP_DMA | __GFP_NOWARN;
2482         else
2483                 page_mask = GFP_ATOMIC | __GFP_NOWARN;
2484
2485         for (order = 0, a_size = PAGE_SIZE; a_size < rqSz;
2486              order++, a_size <<= 1) ;
2487         resp = alloc_pages(page_mask, order);
2488         while ((!resp) && order && retSzp) {
2489                 --order;
2490                 a_size >>= 1;   /* divide by 2, until PAGE_SIZE */
2491                 resp =  alloc_pages(page_mask, order);  /* try half */
2492                 resSz = a_size;
2493         }
2494         if (resp) {
2495                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2496                         memset(page_address(resp), 0, resSz);
2497                 if (retSzp)
2498                         *retSzp = resSz;
2499         }
2500         return resp;
2501 }
2502
2503 static void
2504 sg_page_free(struct page *page, int size)
2505 {
2506         int order, a_size;
2507
2508         if (!page)
2509                 return;
2510         for (order = 0, a_size = PAGE_SIZE; a_size < size;
2511              order++, a_size <<= 1) ;
2512         __free_pages(page, order);
2513 }
2514
2515 #ifndef MAINTENANCE_IN_CMD
2516 #define MAINTENANCE_IN_CMD 0xa3
2517 #endif
2518
2519 static unsigned char allow_ops[] = { TEST_UNIT_READY, REQUEST_SENSE,
2520         INQUIRY, READ_CAPACITY, READ_BUFFER, READ_6, READ_10, READ_12,
2521         READ_16, MODE_SENSE, MODE_SENSE_10, LOG_SENSE, REPORT_LUNS,
2522         SERVICE_ACTION_IN, RECEIVE_DIAGNOSTIC, READ_LONG, MAINTENANCE_IN_CMD
2523 };
2524
2525 static int
2526 sg_allow_access(unsigned char opcode, char dev_type)
2527 {
2528         int k;
2529
2530         if (TYPE_SCANNER == dev_type)   /* TYPE_ROM maybe burner */
2531                 return 1;
2532         for (k = 0; k < sizeof (allow_ops); ++k) {
2533                 if (opcode == allow_ops[k])
2534                         return 1;
2535         }
2536         return 0;
2537 }
2538
2539 #ifdef CONFIG_SCSI_PROC_FS
2540 static int
2541 sg_last_dev(void)
2542 {
2543         int k;
2544         unsigned long iflags;
2545
2546         read_lock_irqsave(&sg_dev_arr_lock, iflags);
2547         for (k = sg_dev_max - 1; k >= 0; --k)
2548                 if (sg_dev_arr[k] && sg_dev_arr[k]->device)
2549                         break;
2550         read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2551         return k + 1;           /* origin 1 */
2552 }
2553 #endif
2554
2555 static Sg_device *
2556 sg_get_dev(int dev)
2557 {
2558         Sg_device *sdp = NULL;
2559         unsigned long iflags;
2560
2561         if (sg_dev_arr && (dev >= 0)) {
2562                 read_lock_irqsave(&sg_dev_arr_lock, iflags);
2563                 if (dev < sg_dev_max)
2564                         sdp = sg_dev_arr[dev];
2565                 read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2566         }
2567         return sdp;
2568 }
2569
2570 #ifdef CONFIG_SCSI_PROC_FS
2571
2572 static struct proc_dir_entry *sg_proc_sgp = NULL;
2573
2574 static char sg_proc_sg_dirname[] = "scsi/sg";
2575
2576 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2577
2578 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2579 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2580                                   size_t count, loff_t *off);
2581 static struct file_operations adio_fops = {
2582         /* .owner, .read and .llseek added in sg_proc_init() */
2583         .open = sg_proc_single_open_adio,
2584         .write = sg_proc_write_adio,
2585         .release = single_release,
2586 };
2587
2588 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2589 static ssize_t sg_proc_write_dressz(struct file *filp,
2590                 const char __user *buffer, size_t count, loff_t *off);
2591 static struct file_operations dressz_fops = {
2592         .open = sg_proc_single_open_dressz,
2593         .write = sg_proc_write_dressz,
2594         .release = single_release,
2595 };
2596
2597 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2598 static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2599 static struct file_operations version_fops = {
2600         .open = sg_proc_single_open_version,
2601         .release = single_release,
2602 };
2603
2604 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2605 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2606 static struct file_operations devhdr_fops = {
2607         .open = sg_proc_single_open_devhdr,
2608         .release = single_release,
2609 };
2610
2611 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2612 static int sg_proc_open_dev(struct inode *inode, struct file *file);
2613 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2614 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2615 static void dev_seq_stop(struct seq_file *s, void *v);
2616 static struct file_operations dev_fops = {
2617         .open = sg_proc_open_dev,
2618         .release = seq_release,
2619 };
2620 static struct seq_operations dev_seq_ops = {
2621         .start = dev_seq_start,
2622         .next  = dev_seq_next,
2623         .stop  = dev_seq_stop,
2624         .show  = sg_proc_seq_show_dev,
2625 };
2626
2627 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2628 static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2629 static struct file_operations devstrs_fops = {
2630         .open = sg_proc_open_devstrs,
2631         .release = seq_release,
2632 };
2633 static struct seq_operations devstrs_seq_ops = {
2634         .start = dev_seq_start,
2635         .next  = dev_seq_next,
2636         .stop  = dev_seq_stop,
2637         .show  = sg_proc_seq_show_devstrs,
2638 };
2639
2640 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2641 static int sg_proc_open_debug(struct inode *inode, struct file *file);
2642 static struct file_operations debug_fops = {
2643         .open = sg_proc_open_debug,
2644         .release = seq_release,
2645 };
2646 static struct seq_operations debug_seq_ops = {
2647         .start = dev_seq_start,
2648         .next  = dev_seq_next,
2649         .stop  = dev_seq_stop,
2650         .show  = sg_proc_seq_show_debug,
2651 };
2652
2653
2654 struct sg_proc_leaf {
2655         const char * name;
2656         struct file_operations * fops;
2657 };
2658
2659 static struct sg_proc_leaf sg_proc_leaf_arr[] = {
2660         {"allow_dio", &adio_fops},
2661         {"debug", &debug_fops},
2662         {"def_reserved_size", &dressz_fops},
2663         {"device_hdr", &devhdr_fops},
2664         {"devices", &dev_fops},
2665         {"device_strs", &devstrs_fops},
2666         {"version", &version_fops}
2667 };
2668
2669 static int
2670 sg_proc_init(void)
2671 {
2672         int k, mask;
2673         int num_leaves =
2674             sizeof (sg_proc_leaf_arr) / sizeof (sg_proc_leaf_arr[0]);
2675         struct proc_dir_entry *pdep;
2676         struct sg_proc_leaf * leaf;
2677
2678         sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2679         if (!sg_proc_sgp)
2680                 return 1;
2681         for (k = 0; k < num_leaves; ++k) {
2682                 leaf = &sg_proc_leaf_arr[k];
2683                 mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2684                 pdep = create_proc_entry(leaf->name, mask, sg_proc_sgp);
2685                 if (pdep) {
2686                         leaf->fops->owner = THIS_MODULE,
2687                         leaf->fops->read = seq_read,
2688                         leaf->fops->llseek = seq_lseek,
2689                         pdep->proc_fops = leaf->fops;
2690                 }
2691         }
2692         return 0;
2693 }
2694
2695 static void
2696 sg_proc_cleanup(void)
2697 {
2698         int k;
2699         int num_leaves =
2700             sizeof (sg_proc_leaf_arr) / sizeof (sg_proc_leaf_arr[0]);
2701
2702         if (!sg_proc_sgp)
2703                 return;
2704         for (k = 0; k < num_leaves; ++k)
2705                 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2706         remove_proc_entry(sg_proc_sg_dirname, NULL);
2707 }
2708
2709
2710 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2711 {
2712         seq_printf(s, "%d\n", *((int *)s->private));
2713         return 0;
2714 }
2715
2716 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2717 {
2718         return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2719 }
2720
2721 static ssize_t
2722 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2723                    size_t count, loff_t *off)
2724 {
2725         int num;
2726         char buff[11];
2727
2728         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2729                 return -EACCES;
2730         num = (count < 10) ? count : 10;
2731         if (copy_from_user(buff, buffer, num))
2732                 return -EFAULT;
2733         buff[num] = '\0';
2734         sg_allow_dio = simple_strtoul(buff, NULL, 10) ? 1 : 0;
2735         return count;
2736 }
2737
2738 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2739 {
2740         return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2741 }
2742
2743 static ssize_t
2744 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2745                      size_t count, loff_t *off)
2746 {
2747         int num;
2748         unsigned long k = ULONG_MAX;
2749         char buff[11];
2750
2751         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2752                 return -EACCES;
2753         num = (count < 10) ? count : 10;
2754         if (copy_from_user(buff, buffer, num))
2755                 return -EFAULT;
2756         buff[num] = '\0';
2757         k = simple_strtoul(buff, NULL, 10);
2758         if (k <= 1048576) {     /* limit "big buff" to 1 MB */
2759                 sg_big_buff = k;
2760                 return count;
2761         }
2762         return -ERANGE;
2763 }
2764
2765 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2766 {
2767         seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2768                    sg_version_date);
2769         return 0;
2770 }
2771
2772 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2773 {
2774         return single_open(file, sg_proc_seq_show_version, NULL);
2775 }
2776
2777 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2778 {
2779         seq_printf(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\t"
2780                    "online\n");
2781         return 0;
2782 }
2783
2784 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2785 {
2786         return single_open(file, sg_proc_seq_show_devhdr, NULL);
2787 }
2788
2789 struct sg_proc_deviter {
2790         loff_t  index;
2791         size_t  max;
2792 };
2793
2794 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2795 {
2796         struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2797
2798         s->private = it;
2799         if (! it)
2800                 return NULL;
2801
2802         if (NULL == sg_dev_arr)
2803                 return NULL;
2804         it->index = *pos;
2805         it->max = sg_last_dev();
2806         if (it->index >= it->max)
2807                 return NULL;
2808         return it;
2809 }
2810
2811 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2812 {
2813         struct sg_proc_deviter * it = s->private;
2814
2815         *pos = ++it->index;
2816         return (it->index < it->max) ? it : NULL;
2817 }
2818
2819 static void dev_seq_stop(struct seq_file *s, void *v)
2820 {
2821         kfree(s->private);
2822 }
2823
2824 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2825 {
2826         return seq_open(file, &dev_seq_ops);
2827 }
2828
2829 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2830 {
2831         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2832         Sg_device *sdp;
2833         struct scsi_device *scsidp;
2834
2835         sdp = it ? sg_get_dev(it->index) : NULL;
2836         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2837                 seq_printf(s, "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n",
2838                               scsidp->host->host_no, scsidp->channel,
2839                               scsidp->id, scsidp->lun, (int) scsidp->type,
2840                               1,
2841                               (int) scsidp->queue_depth,
2842                               (int) scsidp->device_busy,
2843                               (int) scsi_device_online(scsidp));
2844         else
2845                 seq_printf(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2846         return 0;
2847 }
2848
2849 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2850 {
2851         return seq_open(file, &devstrs_seq_ops);
2852 }
2853
2854 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2855 {
2856         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2857         Sg_device *sdp;
2858         struct scsi_device *scsidp;
2859
2860         sdp = it ? sg_get_dev(it->index) : NULL;
2861         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2862                 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2863                            scsidp->vendor, scsidp->model, scsidp->rev);
2864         else
2865                 seq_printf(s, "<no active device>\n");
2866         return 0;
2867 }
2868
2869 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2870 {
2871         int k, m, new_interface, blen, usg;
2872         Sg_request *srp;
2873         Sg_fd *fp;
2874         const sg_io_hdr_t *hp;
2875         const char * cp;
2876         unsigned int ms;
2877
2878         for (k = 0; (fp = sg_get_nth_sfp(sdp, k)); ++k) {
2879                 seq_printf(s, "   FD(%d): timeout=%dms bufflen=%d "
2880                            "(res)sgat=%d low_dma=%d\n", k + 1,
2881                            jiffies_to_msecs(fp->timeout),
2882                            fp->reserve.bufflen,
2883                            (int) fp->reserve.k_use_sg,
2884                            (int) fp->low_dma);
2885                 seq_printf(s, "   cmd_q=%d f_packid=%d k_orphan=%d closed=%d\n",
2886                            (int) fp->cmd_q, (int) fp->force_packid,
2887                            (int) fp->keep_orphan, (int) fp->closed);
2888                 for (m = 0; (srp = sg_get_nth_request(fp, m)); ++m) {
2889                         hp = &srp->header;
2890                         new_interface = (hp->interface_id == '\0') ? 0 : 1;
2891                         if (srp->res_used) {
2892                                 if (new_interface &&
2893                                     (SG_FLAG_MMAP_IO & hp->flags))
2894                                         cp = "     mmap>> ";
2895                                 else
2896                                         cp = "     rb>> ";
2897                         } else {
2898                                 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2899                                         cp = "     dio>> ";
2900                                 else
2901                                         cp = "     ";
2902                         }
2903                         seq_printf(s, cp);
2904                         blen = srp->data.bufflen;
2905                         usg = srp->data.k_use_sg;
2906                         seq_printf(s, srp->done ?
2907                                    ((1 == srp->done) ?  "rcv:" : "fin:")
2908                                    : "act:");
2909                         seq_printf(s, " id=%d blen=%d",
2910                                    srp->header.pack_id, blen);
2911                         if (srp->done)
2912                                 seq_printf(s, " dur=%d", hp->duration);
2913                         else {
2914                                 ms = jiffies_to_msecs(jiffies);
2915                                 seq_printf(s, " t_o/elap=%d/%d",
2916                                         (new_interface ? hp->timeout :
2917                                                   jiffies_to_msecs(fp->timeout)),
2918                                         (ms > hp->duration ? ms - hp->duration : 0));
2919                         }
2920                         seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2921                                    (int) srp->data.cmd_opcode);
2922                 }
2923                 if (0 == m)
2924                         seq_printf(s, "     No requests active\n");
2925         }
2926 }
2927
2928 static int sg_proc_open_debug(struct inode *inode, struct file *file)
2929 {
2930         return seq_open(file, &debug_seq_ops);
2931 }
2932
2933 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2934 {
2935         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2936         Sg_device *sdp;
2937
2938         if (it && (0 == it->index)) {
2939                 seq_printf(s, "dev_max(currently)=%d max_active_device=%d "
2940                            "(origin 1)\n", sg_dev_max, (int)it->max);
2941                 seq_printf(s, " def_reserved_size=%d\n", sg_big_buff);
2942         }
2943         sdp = it ? sg_get_dev(it->index) : NULL;
2944         if (sdp) {
2945                 struct scsi_device *scsidp = sdp->device;
2946
2947                 if (NULL == scsidp) {
2948                         seq_printf(s, "device %d detached ??\n",
2949                                    (int)it->index);
2950                         return 0;
2951                 }
2952
2953                 if (sg_get_nth_sfp(sdp, 0)) {
2954                         seq_printf(s, " >>> device=%s ",
2955                                 sdp->disk->disk_name);
2956                         if (sdp->detached)
2957                                 seq_printf(s, "detached pending close ");
2958                         else
2959                                 seq_printf
2960                                     (s, "scsi%d chan=%d id=%d lun=%d   em=%d",
2961                                      scsidp->host->host_no,
2962                                      scsidp->channel, scsidp->id,
2963                                      scsidp->lun,
2964                                      scsidp->host->hostt->emulated);
2965                         seq_printf(s, " sg_tablesize=%d excl=%d\n",
2966                                    sdp->sg_tablesize, sdp->exclude);
2967                 }
2968                 sg_proc_debug_helper(s, sdp);
2969         }
2970         return 0;
2971 }
2972
2973 #endif                          /* CONFIG_SCSI_PROC_FS */
2974
2975 module_init(init_sg);
2976 module_exit(exit_sg);
2977 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);