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 = 30534;      /* 2 digits for each component */
  22 #define SG_VERSION_STR "3.5.34"
  23
  24 /*
  25  *  D. P. Gilbert (dgilbert@interlog.com, dougg@triode.net.au), notes:
  26  *      - scsi logging is available via SCSI_LOG_TIMEOUT macros. First
  27  *        the kernel/module needs to be built with CONFIG_SCSI_LOGGING
  28  *        (otherwise the macros compile to empty statements).
  29  *
  30  */
  31 #include <linux/module.h>
  32
  33 #include <linux/fs.h>
  34 #include <linux/kernel.h>
  35 #include <linux/sched.h>
  36 #include <linux/string.h>
  37 #include <linux/mm.h>
  38 #include <linux/errno.h>
  39 #include <linux/mtio.h>
  40 #include <linux/ioctl.h>
  41 #include <linux/fcntl.h>
  42 #include <linux/init.h>
  43 #include <linux/poll.h>
  44 #include <linux/moduleparam.h>
  45 #include <linux/cdev.h>
  46 #include <linux/idr.h>
  47 #include <linux/seq_file.h>
  48 #include <linux/blkdev.h>
  49 #include <linux/delay.h>
  50 #include <linux/blktrace_api.h>
  51 #include <linux/smp_lock.h>
  52
  53 #include "scsi.h"
  54 #include <scsi/scsi_dbg.h>
  55 #include <scsi/scsi_host.h>
  56 #include <scsi/scsi_driver.h>
  57 #include <scsi/scsi_ioctl.h>
  58 #include <scsi/sg.h>
  59
  60 #include "scsi_logging.h"
  61
  62 #ifdef CONFIG_SCSI_PROC_FS
  63 #include <linux/proc_fs.h>
  64 static char *sg_version_date = "20061027";
  65
  66 static int sg_proc_init(void);
  67 static void sg_proc_cleanup(void);
  68 #endif
  69
  70 #define SG_ALLOW_DIO_DEF 0
  71
  72 #define SG_MAX_DEVS 32768
  73
  74 /*
  75  * Suppose you want to calculate the formula muldiv(x,m,d)=int(x * m / d)
  76  * Then when using 32 bit integers x * m may overflow during the calculation.
  77  * Replacing muldiv(x) by muldiv(x)=((x % d) * m) / d + int(x / d) * m
  78  * calculates the same, but prevents the overflow when both m and d
  79  * are "small" numbers (like HZ and USER_HZ).
  80  * Of course an overflow is inavoidable if the result of muldiv doesn't fit
  81  * in 32 bits.
  82  */
  83 #define MULDIV(X,MUL,DIV) ((((X % DIV) * MUL) / DIV) + ((X / DIV) * MUL))
  84
  85 #define SG_DEFAULT_TIMEOUT MULDIV(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
  86
  87 int sg_big_buff = SG_DEF_RESERVED_SIZE;
  88 /* N.B. This variable is readable and writeable via
  89    /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
  90    of this size (or less if there is not enough memory) will be reserved
  91    for use by this file descriptor. [Deprecated usage: this variable is also
  92    readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
  93    the kernel (i.e. it is not a module).] */
  94 static int def_reserved_size = -1;      /* picks up init parameter */
  95 static int sg_allow_dio = SG_ALLOW_DIO_DEF;
  96
  97 static int scatter_elem_sz = SG_SCATTER_SZ;
  98 static int scatter_elem_sz_prev = SG_SCATTER_SZ;
  99
 100 #define SG_SECTOR_SZ 512
 101
 102 static int sg_add(struct device *, struct class_interface *);
 103 static void sg_remove(struct device *, struct class_interface *);
 104
 105 static DEFINE_IDR(sg_index_idr);
 106 static DEFINE_RWLOCK(sg_index_lock);    /* Also used to lock
 107                                                            file descriptor list for device */
 108
 109 static struct class_interface sg_interface = {
 110         .add_dev        = sg_add,
 111         .remove_dev     = sg_remove,
 112 };
 113
 114 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
 115         unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
 116         unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */
 117         unsigned bufflen;       /* Size of (aggregate) data buffer */
 118         struct page **pages;
 119         int page_order;
 120         char dio_in_use;        /* 0->indirect IO (or mmap), 1->dio */
 121         unsigned char cmd_opcode; /* first byte of command */
 122 } Sg_scatter_hold;
 123
 124 struct sg_device;               /* forward declarations */
 125 struct sg_fd;
 126
 127 typedef struct sg_request {     /* SG_MAX_QUEUE requests outstanding per file */
 128         struct sg_request *nextrp;      /* NULL -> tail request (slist) */
 129         struct sg_fd *parentfp; /* NULL -> not in use */
 130         Sg_scatter_hold data;   /* hold buffer, perhaps scatter list */
 131         sg_io_hdr_t header;     /* scsi command+info, see <scsi/sg.h> */
 132         unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
 133         char res_used;          /* 1 -> using reserve buffer, 0 -> not ... */
 134         char orphan;            /* 1 -> drop on sight, 0 -> normal */
 135         char sg_io_owned;       /* 1 -> packet belongs to SG_IO */
 136         volatile char done;     /* 0->before bh, 1->before read, 2->read */
 137         struct request *rq;
 138         struct bio *bio;
 139         struct execute_work ew;
 140 } Sg_request;
 141
 142 typedef struct sg_fd {          /* holds the state of a file descriptor */
 143         struct list_head sfd_siblings;
 144         struct sg_device *parentdp;     /* owning device */
 145         wait_queue_head_t read_wait;    /* queue read until command done */
 146         rwlock_t rq_list_lock;  /* protect access to list in req_arr */
 147         int timeout;            /* defaults to SG_DEFAULT_TIMEOUT      */
 148         int timeout_user;       /* defaults to SG_DEFAULT_TIMEOUT_USER */
 149         Sg_scatter_hold reserve;        /* buffer held for this file descriptor */
 150         unsigned save_scat_len; /* original length of trunc. scat. element */
 151         Sg_request *headrp;     /* head of request slist, NULL->empty */
 152         struct fasync_struct *async_qp; /* used by asynchronous notification */
 153         Sg_request req_arr[SG_MAX_QUEUE];       /* used as singly-linked list */
 154         char low_dma;           /* as in parent but possibly overridden to 1 */
 155         char force_packid;      /* 1 -> pack_id input to read(), 0 -> ignored */
 156         volatile char closed;   /* 1 -> fd closed but request(s) outstanding */
 157         char cmd_q;             /* 1 -> allow command queuing, 0 -> don't */
 158         char next_cmd_len;      /* 0 -> automatic (def), >0 -> use on next write() */
 159         char keep_orphan;       /* 0 -> drop orphan (def), 1 -> keep for read() */
 160         char mmap_called;       /* 0 -> mmap() never called on this fd */
 161         struct kref f_ref;
 162         struct execute_work ew;
 163 } Sg_fd;
 164
 165 typedef struct sg_device { /* holds the state of each scsi generic device */
 166         struct scsi_device *device;
 167         wait_queue_head_t o_excl_wait;  /* queue open() when O_EXCL in use */
 168         int sg_tablesize;       /* adapter's max scatter-gather table size */
 169         u32 index;              /* device index number */
 170         struct list_head sfds;
 171         volatile char detached; /* 0->attached, 1->detached pending removal */
 172         volatile char exclude;  /* opened for exclusive access */
 173         char sgdebug;           /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
 174         struct gendisk *disk;
 175         struct cdev * cdev;     /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
 176         struct kref d_ref;
 177 } Sg_device;
 178
 179 /* tasklet or soft irq callback */
 180 static void sg_rq_end_io(struct request *rq, int uptodate);
 181 static int sg_start_req(Sg_request *srp, unsigned char *cmd);
 182 static int sg_finish_rem_req(Sg_request * srp);
 183 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
 184 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
 185                            Sg_request * srp);
 186 static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
 187                         const char __user *buf, size_t count, int blocking,
 188                         int read_only, int sg_io_owned, Sg_request **o_srp);
 189 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
 190                            unsigned char *cmnd, int timeout, int blocking);
 191 static int sg_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 Sg_fd *sg_add_sfp(Sg_device * sdp, int dev);
 197 static void sg_remove_sfp(struct kref *);
 198 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
 199 static Sg_request *sg_add_request(Sg_fd * sfp);
 200 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
 201 static int sg_res_in_use(Sg_fd * sfp);
 202 static Sg_device *sg_get_dev(int dev);
 203 static void sg_put_dev(Sg_device *sdp);
 204
 205 #define SZ_SG_HEADER sizeof(struct sg_header)
 206 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
 207 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
 208 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
 209
 210 static int sg_allow_access(struct file *filp, unsigned char *cmd)
 211 {
 212         struct sg_fd *sfp = (struct sg_fd *)filp->private_data;
 213
 214         if (sfp->parentdp->device->type == TYPE_SCANNER)
 215                 return 0;
 216
 217         return blk_verify_command(cmd, filp->f_mode & FMODE_WRITE);
 218 }
 219
 220 static int
 221 sg_open(struct inode *inode, struct file *filp)
 222 {
 223         int dev = iminor(inode);
 224         int flags = filp->f_flags;
 225         struct request_queue *q;
 226         Sg_device *sdp;
 227         Sg_fd *sfp;
 228         int res;
 229         int retval;
 230
 231         lock_kernel();
 232         nonseekable_open(inode, filp);
 233         SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags));
 234         sdp = sg_get_dev(dev);
 235         if (IS_ERR(sdp)) {
 236                 retval = PTR_ERR(sdp);
 237                 sdp = NULL;
 238                 goto sg_put;
 239         }
 240
 241         /* This driver's module count bumped by fops_get in <linux/fs.h> */
 242         /* Prevent the device driver from vanishing while we sleep */
 243         retval = scsi_device_get(sdp->device);
 244         if (retval)
 245                 goto sg_put;
 246
 247         if (!((flags & O_NONBLOCK) ||
 248               scsi_block_when_processing_errors(sdp->device))) {
 249                 retval = -ENXIO;
 250                 /* we are in error recovery for this device */
 251                 goto error_out;
 252         }
 253
 254         if (flags & O_EXCL) {
 255                 if (O_RDONLY == (flags & O_ACCMODE)) {
 256                         retval = -EPERM; /* Can't lock it with read only access */
 257                         goto error_out;
 258                 }
 259                 if (!list_empty(&sdp->sfds) && (flags & O_NONBLOCK)) {
 260                         retval = -EBUSY;
 261                         goto error_out;
 262                 }
 263                 res = 0;
 264                 __wait_event_interruptible(sdp->o_excl_wait,
 265                                            ((!list_empty(&sdp->sfds) || sdp->exclude) ? 0 : (sdp->exclude = 1)), res);
 266                 if (res) {
 267                         retval = res;   /* -ERESTARTSYS because signal hit process */
 268                         goto error_out;
 269                 }
 270         } else if (sdp->exclude) {      /* some other fd has an exclusive lock on dev */
 271                 if (flags & O_NONBLOCK) {
 272                         retval = -EBUSY;
 273                         goto error_out;
 274                 }
 275                 res = 0;
 276                 __wait_event_interruptible(sdp->o_excl_wait, (!sdp->exclude),
 277                                            res);
 278                 if (res) {
 279                         retval = res;   /* -ERESTARTSYS because signal hit process */
 280                         goto error_out;
 281                 }
 282         }
 283         if (sdp->detached) {
 284                 retval = -ENODEV;
 285                 goto error_out;
 286         }
 287         if (list_empty(&sdp->sfds)) {   /* no existing opens on this device */
 288                 sdp->sgdebug = 0;
 289                 q = sdp->device->request_queue;
 290                 sdp->sg_tablesize = min(queue_max_hw_segments(q),
 291                                         queue_max_phys_segments(q));
 292         }
 293         if ((sfp = sg_add_sfp(sdp, dev)))
 294                 filp->private_data = sfp;
 295         else {
 296                 if (flags & O_EXCL) {
 297                         sdp->exclude = 0;       /* undo if error */
 298                         wake_up_interruptible(&sdp->o_excl_wait);
 299                 }
 300                 retval = -ENOMEM;
 301                 goto error_out;
 302         }
 303         retval = 0;
 304 error_out:
 305         if (retval)
 306                 scsi_device_put(sdp->device);
 307 sg_put:
 308         if (sdp)
 309                 sg_put_dev(sdp);
 310         unlock_kernel();
 311         return retval;
 312 }
 313
 314 /* Following function was formerly called 'sg_close' */
 315 static int
 316 sg_release(struct inode *inode, struct file *filp)
 317 {
 318         Sg_device *sdp;
 319         Sg_fd *sfp;
 320
 321         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 322                 return -ENXIO;
 323         SCSI_LOG_TIMEOUT(3, printk("sg_release: %s\n", sdp->disk->disk_name));
 324
 325         sfp->closed = 1;
 326
 327         sdp->exclude = 0;
 328         wake_up_interruptible(&sdp->o_excl_wait);
 329
 330         kref_put(&sfp->f_ref, sg_remove_sfp);
 331         return 0;
 332 }
 333
 334 static ssize_t
 335 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
 336 {
 337         Sg_device *sdp;
 338         Sg_fd *sfp;
 339         Sg_request *srp;
 340         int req_pack_id = -1;
 341         sg_io_hdr_t *hp;
 342         struct sg_header *old_hdr = NULL;
 343         int retval = 0;
 344
 345         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 346                 return -ENXIO;
 347         SCSI_LOG_TIMEOUT(3, printk("sg_read: %s, count=%d\n",
 348                                    sdp->disk->disk_name, (int) count));
 349
 350         if (!access_ok(VERIFY_WRITE, buf, count))
 351                 return -EFAULT;
 352         if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
 353                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 354                 if (!old_hdr)
 355                         return -ENOMEM;
 356                 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
 357                         retval = -EFAULT;
 358                         goto free_old_hdr;
 359                 }
 360                 if (old_hdr->reply_len < 0) {
 361                         if (count >= SZ_SG_IO_HDR) {
 362                                 sg_io_hdr_t *new_hdr;
 363                                 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
 364                                 if (!new_hdr) {
 365                                         retval = -ENOMEM;
 366                                         goto free_old_hdr;
 367                                 }
 368                                 retval =__copy_from_user
 369                                     (new_hdr, buf, SZ_SG_IO_HDR);
 370                                 req_pack_id = new_hdr->pack_id;
 371                                 kfree(new_hdr);
 372                                 if (retval) {
 373                                         retval = -EFAULT;
 374                                         goto free_old_hdr;
 375                                 }
 376                         }
 377                 } else
 378                         req_pack_id = old_hdr->pack_id;
 379         }
 380         srp = sg_get_rq_mark(sfp, req_pack_id);
 381         if (!srp) {             /* now wait on packet to arrive */
 382                 if (sdp->detached) {
 383                         retval = -ENODEV;
 384                         goto free_old_hdr;
 385                 }
 386                 if (filp->f_flags & O_NONBLOCK) {
 387                         retval = -EAGAIN;
 388                         goto free_old_hdr;
 389                 }
 390                 while (1) {
 391                         retval = 0; /* following macro beats race condition */
 392                         __wait_event_interruptible(sfp->read_wait,
 393                                 (sdp->detached ||
 394                                 (srp = sg_get_rq_mark(sfp, req_pack_id))),
 395                                 retval);
 396                         if (sdp->detached) {
 397                                 retval = -ENODEV;
 398                                 goto free_old_hdr;
 399                         }
 400                         if (0 == retval)
 401                                 break;
 402
 403                         /* -ERESTARTSYS as signal hit process */
 404                         goto free_old_hdr;
 405                 }
 406         }
 407         if (srp->header.interface_id != '\0') {
 408                 retval = sg_new_read(sfp, buf, count, srp);
 409                 goto free_old_hdr;
 410         }
 411
 412         hp = &srp->header;
 413         if (old_hdr == NULL) {
 414                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 415                 if (! old_hdr) {
 416                         retval = -ENOMEM;
 417                         goto free_old_hdr;
 418                 }
 419         }
 420         memset(old_hdr, 0, SZ_SG_HEADER);
 421         old_hdr->reply_len = (int) hp->timeout;
 422         old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
 423         old_hdr->pack_id = hp->pack_id;
 424         old_hdr->twelve_byte =
 425             ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
 426         old_hdr->target_status = hp->masked_status;
 427         old_hdr->host_status = hp->host_status;
 428         old_hdr->driver_status = hp->driver_status;
 429         if ((CHECK_CONDITION & hp->masked_status) ||
 430             (DRIVER_SENSE & hp->driver_status))
 431                 memcpy(old_hdr->sense_buffer, srp->sense_b,
 432                        sizeof (old_hdr->sense_buffer));
 433         switch (hp->host_status) {
 434         /* This setup of 'result' is for backward compatibility and is best
 435            ignored by the user who should use target, host + driver status */
 436         case DID_OK:
 437         case DID_PASSTHROUGH:
 438         case DID_SOFT_ERROR:
 439                 old_hdr->result = 0;
 440                 break;
 441         case DID_NO_CONNECT:
 442         case DID_BUS_BUSY:
 443         case DID_TIME_OUT:
 444                 old_hdr->result = EBUSY;
 445                 break;
 446         case DID_BAD_TARGET:
 447         case DID_ABORT:
 448         case DID_PARITY:
 449         case DID_RESET:
 450         case DID_BAD_INTR:
 451                 old_hdr->result = EIO;
 452                 break;
 453         case DID_ERROR:
 454                 old_hdr->result = (srp->sense_b[0] == 0 &&
 455                                   hp->masked_status == GOOD) ? 0 : EIO;
 456                 break;
 457         default:
 458                 old_hdr->result = EIO;
 459                 break;
 460         }
 461
 462         /* Now copy the result back to the user buffer.  */
 463         if (count >= SZ_SG_HEADER) {
 464                 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
 465                         retval = -EFAULT;
 466                         goto free_old_hdr;
 467                 }
 468                 buf += SZ_SG_HEADER;
 469                 if (count > old_hdr->reply_len)
 470                         count = old_hdr->reply_len;
 471                 if (count > SZ_SG_HEADER) {
 472                         if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
 473                                 retval = -EFAULT;
 474                                 goto free_old_hdr;
 475                         }
 476                 }
 477         } else
 478                 count = (old_hdr->result == 0) ? 0 : -EIO;
 479         sg_finish_rem_req(srp);
 480         retval = count;
 481 free_old_hdr:
 482         kfree(old_hdr);
 483         return retval;
 484 }
 485
 486 static ssize_t
 487 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
 488 {
 489         sg_io_hdr_t *hp = &srp->header;
 490         int err = 0;
 491         int len;
 492
 493         if (count < SZ_SG_IO_HDR) {
 494                 err = -EINVAL;
 495                 goto err_out;
 496         }
 497         hp->sb_len_wr = 0;
 498         if ((hp->mx_sb_len > 0) && hp->sbp) {
 499                 if ((CHECK_CONDITION & hp->masked_status) ||
 500                     (DRIVER_SENSE & hp->driver_status)) {
 501                         int sb_len = SCSI_SENSE_BUFFERSIZE;
 502                         sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
 503                         len = 8 + (int) srp->sense_b[7];        /* Additional sense length field */
 504                         len = (len > sb_len) ? sb_len : len;
 505                         if (copy_to_user(hp->sbp, srp->sense_b, len)) {
 506                                 err = -EFAULT;
 507                                 goto err_out;
 508                         }
 509                         hp->sb_len_wr = len;
 510                 }
 511         }
 512         if (hp->masked_status || hp->host_status || hp->driver_status)
 513                 hp->info |= SG_INFO_CHECK;
 514         if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
 515                 err = -EFAULT;
 516                 goto err_out;
 517         }
 518 err_out:
 519         err = sg_finish_rem_req(srp);
 520         return (0 == err) ? count : err;
 521 }
 522
 523 static ssize_t
 524 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
 525 {
 526         int mxsize, cmd_size, k;
 527         int input_size, blocking;
 528         unsigned char opcode;
 529         Sg_device *sdp;
 530         Sg_fd *sfp;
 531         Sg_request *srp;
 532         struct sg_header old_hdr;
 533         sg_io_hdr_t *hp;
 534         unsigned char cmnd[MAX_COMMAND_SIZE];
 535
 536         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 537                 return -ENXIO;
 538         SCSI_LOG_TIMEOUT(3, printk("sg_write: %s, count=%d\n",
 539                                    sdp->disk->disk_name, (int) count));
 540         if (sdp->detached)
 541                 return -ENODEV;
 542         if (!((filp->f_flags & O_NONBLOCK) ||
 543               scsi_block_when_processing_errors(sdp->device)))
 544                 return -ENXIO;
 545
 546         if (!access_ok(VERIFY_READ, buf, count))
 547                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 548         if (count < SZ_SG_HEADER)
 549                 return -EIO;
 550         if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
 551                 return -EFAULT;
 552         blocking = !(filp->f_flags & O_NONBLOCK);
 553         if (old_hdr.reply_len < 0)
 554                 return sg_new_write(sfp, filp, buf, count,
 555                                     blocking, 0, 0, NULL);
 556         if (count < (SZ_SG_HEADER + 6))
 557                 return -EIO;    /* The minimum scsi command length is 6 bytes. */
 558
 559         if (!(srp = sg_add_request(sfp))) {
 560                 SCSI_LOG_TIMEOUT(1, printk("sg_write: queue full\n"));
 561                 return -EDOM;
 562         }
 563         buf += SZ_SG_HEADER;
 564         __get_user(opcode, buf);
 565         if (sfp->next_cmd_len > 0) {
 566                 if (sfp->next_cmd_len > MAX_COMMAND_SIZE) {
 567                         SCSI_LOG_TIMEOUT(1, printk("sg_write: command length too long\n"));
 568                         sfp->next_cmd_len = 0;
 569                         sg_remove_request(sfp, srp);
 570                         return -EIO;
 571                 }
 572                 cmd_size = sfp->next_cmd_len;
 573                 sfp->next_cmd_len = 0;  /* reset so only this write() effected */
 574         } else {
 575                 cmd_size = COMMAND_SIZE(opcode);        /* based on SCSI command group */
 576                 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
 577                         cmd_size = 12;
 578         }
 579         SCSI_LOG_TIMEOUT(4, printk(
 580                 "sg_write:   scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
 581 /* Determine buffer size.  */
 582         input_size = count - cmd_size;
 583         mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
 584         mxsize -= SZ_SG_HEADER;
 585         input_size -= SZ_SG_HEADER;
 586         if (input_size < 0) {
 587                 sg_remove_request(sfp, srp);
 588                 return -EIO;    /* User did not pass enough bytes for this command. */
 589         }
 590         hp = &srp->header;
 591         hp->interface_id = '\0';        /* indicator of old interface tunnelled */
 592         hp->cmd_len = (unsigned char) cmd_size;
 593         hp->iovec_count = 0;
 594         hp->mx_sb_len = 0;
 595         if (input_size > 0)
 596                 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
 597                     SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
 598         else
 599                 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
 600         hp->dxfer_len = mxsize;
 601         if (hp->dxfer_direction == SG_DXFER_TO_DEV)
 602                 hp->dxferp = (char __user *)buf + cmd_size;
 603         else
 604                 hp->dxferp = NULL;
 605         hp->sbp = NULL;
 606         hp->timeout = old_hdr.reply_len;        /* structure abuse ... */
 607         hp->flags = input_size; /* structure abuse ... */
 608         hp->pack_id = old_hdr.pack_id;
 609         hp->usr_ptr = NULL;
 610         if (__copy_from_user(cmnd, buf, cmd_size))
 611                 return -EFAULT;
 612         /*
 613          * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
 614          * but is is possible that the app intended SG_DXFER_TO_DEV, because there
 615          * is a non-zero input_size, so emit a warning.
 616          */
 617         if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
 618                 static char cmd[TASK_COMM_LEN];
 619                 if (strcmp(current->comm, cmd) && printk_ratelimit()) {
 620                         printk(KERN_WARNING
 621                                "sg_write: data in/out %d/%d bytes for SCSI command 0x%x--"
 622                                "guessing data in;\n   "
 623                                "program %s not setting count and/or reply_len properly\n",
 624                                old_hdr.reply_len - (int)SZ_SG_HEADER,
 625                                input_size, (unsigned int) cmnd[0],
 626                                current->comm);
 627                         strcpy(cmd, current->comm);
 628                 }
 629         }
 630         k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
 631         return (k < 0) ? k : count;
 632 }
 633
 634 static ssize_t
 635 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
 636                  size_t count, int blocking, int read_only, int sg_io_owned,
 637                  Sg_request **o_srp)
 638 {
 639         int k;
 640         Sg_request *srp;
 641         sg_io_hdr_t *hp;
 642         unsigned char cmnd[MAX_COMMAND_SIZE];
 643         int timeout;
 644         unsigned long ul_timeout;
 645
 646         if (count < SZ_SG_IO_HDR)
 647                 return -EINVAL;
 648         if (!access_ok(VERIFY_READ, buf, count))
 649                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 650
 651         sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
 652         if (!(srp = sg_add_request(sfp))) {
 653                 SCSI_LOG_TIMEOUT(1, printk("sg_new_write: queue full\n"));
 654                 return -EDOM;
 655         }
 656         srp->sg_io_owned = sg_io_owned;
 657         hp = &srp->header;
 658         if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
 659                 sg_remove_request(sfp, srp);
 660                 return -EFAULT;
 661         }
 662         if (hp->interface_id != 'S') {
 663                 sg_remove_request(sfp, srp);
 664                 return -ENOSYS;
 665         }
 666         if (hp->flags & SG_FLAG_MMAP_IO) {
 667                 if (hp->dxfer_len > sfp->reserve.bufflen) {
 668                         sg_remove_request(sfp, srp);
 669                         return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
 670                 }
 671                 if (hp->flags & SG_FLAG_DIRECT_IO) {
 672                         sg_remove_request(sfp, srp);
 673                         return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
 674                 }
 675                 if (sg_res_in_use(sfp)) {
 676                         sg_remove_request(sfp, srp);
 677                         return -EBUSY;  /* reserve buffer already being used */
 678                 }
 679         }
 680         ul_timeout = msecs_to_jiffies(srp->header.timeout);
 681         timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
 682         if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
 683                 sg_remove_request(sfp, srp);
 684                 return -EMSGSIZE;
 685         }
 686         if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
 687                 sg_remove_request(sfp, srp);
 688                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 689         }
 690         if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
 691                 sg_remove_request(sfp, srp);
 692                 return -EFAULT;
 693         }
 694         if (read_only && sg_allow_access(file, cmnd)) {
 695                 sg_remove_request(sfp, srp);
 696                 return -EPERM;
 697         }
 698         k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
 699         if (k < 0)
 700                 return k;
 701         if (o_srp)
 702                 *o_srp = srp;
 703         return count;
 704 }
 705
 706 static int
 707 sg_common_write(Sg_fd * sfp, Sg_request * srp,
 708                 unsigned char *cmnd, int timeout, int blocking)
 709 {
 710         int k, data_dir;
 711         Sg_device *sdp = sfp->parentdp;
 712         sg_io_hdr_t *hp = &srp->header;
 713
 714         srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
 715         hp->status = 0;
 716         hp->masked_status = 0;
 717         hp->msg_status = 0;
 718         hp->info = 0;
 719         hp->host_status = 0;
 720         hp->driver_status = 0;
 721         hp->resid = 0;
 722         SCSI_LOG_TIMEOUT(4, printk("sg_common_write:  scsi opcode=0x%02x, cmd_size=%d\n",
 723                           (int) cmnd[0], (int) hp->cmd_len));
 724
 725         k = sg_start_req(srp, cmnd);
 726         if (k) {
 727                 SCSI_LOG_TIMEOUT(1, printk("sg_common_write: start_req err=%d\n", k));
 728                 sg_finish_rem_req(srp);
 729                 return k;       /* probably out of space --> ENOMEM */
 730         }
 731         if (sdp->detached) {
 732                 sg_finish_rem_req(srp);
 733                 return -ENODEV;
 734         }
 735
 736         switch (hp->dxfer_direction) {
 737         case SG_DXFER_TO_FROM_DEV:
 738         case SG_DXFER_FROM_DEV:
 739                 data_dir = DMA_FROM_DEVICE;
 740                 break;
 741         case SG_DXFER_TO_DEV:
 742                 data_dir = DMA_TO_DEVICE;
 743                 break;
 744         case SG_DXFER_UNKNOWN:
 745                 data_dir = DMA_BIDIRECTIONAL;
 746                 break;
 747         default:
 748                 data_dir = DMA_NONE;
 749                 break;
 750         }
 751         hp->duration = jiffies_to_msecs(jiffies);
 752
 753         srp->rq->timeout = timeout;
 754         kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
 755         blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk,
 756                               srp->rq, 1, sg_rq_end_io);
 757         return 0;
 758 }
 759
 760 static int
 761 sg_ioctl(struct inode *inode, struct file *filp,
 762          unsigned int cmd_in, unsigned long arg)
 763 {
 764         void __user *p = (void __user *)arg;
 765         int __user *ip = p;
 766         int result, val, read_only;
 767         Sg_device *sdp;
 768         Sg_fd *sfp;
 769         Sg_request *srp;
 770         unsigned long iflags;
 771
 772         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 773                 return -ENXIO;
 774
 775         SCSI_LOG_TIMEOUT(3, printk("sg_ioctl: %s, cmd=0x%x\n",
 776                                    sdp->disk->disk_name, (int) cmd_in));
 777         read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
 778
 779         switch (cmd_in) {
 780         case SG_IO:
 781                 {
 782                         int blocking = 1;       /* ignore O_NONBLOCK flag */
 783
 784                         if (sdp->detached)
 785                                 return -ENODEV;
 786                         if (!scsi_block_when_processing_errors(sdp->device))
 787                                 return -ENXIO;
 788                         if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
 789                                 return -EFAULT;
 790                         result =
 791                             sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
 792                                          blocking, read_only, 1, &srp);
 793                         if (result < 0)
 794                                 return result;
 795                         while (1) {
 796                                 result = 0;     /* following macro to beat race condition */
 797                                 __wait_event_interruptible(sfp->read_wait,
 798                                         (srp->done || sdp->detached),
 799                                         result);
 800                                 if (sdp->detached)
 801                                         return -ENODEV;
 802                                 write_lock_irq(&sfp->rq_list_lock);
 803                                 if (srp->done) {
 804                                         srp->done = 2;
 805                                         write_unlock_irq(&sfp->rq_list_lock);
 806                                         break;
 807                                 }
 808                                 srp->orphan = 1;
 809                                 write_unlock_irq(&sfp->rq_list_lock);
 810                                 return result;  /* -ERESTARTSYS because signal hit process */
 811                         }
 812                         result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
 813                         return (result < 0) ? result : 0;
 814                 }
 815         case SG_SET_TIMEOUT:
 816                 result = get_user(val, ip);
 817                 if (result)
 818                         return result;
 819                 if (val < 0)
 820                         return -EIO;
 821                 if (val >= MULDIV (INT_MAX, USER_HZ, HZ))
 822                     val = MULDIV (INT_MAX, USER_HZ, HZ);
 823                 sfp->timeout_user = val;
 824                 sfp->timeout = MULDIV (val, HZ, USER_HZ);
 825
 826                 return 0;
 827         case SG_GET_TIMEOUT:    /* N.B. User receives timeout as return value */
 828                                 /* strange ..., for backward compatibility */
 829                 return sfp->timeout_user;
 830         case SG_SET_FORCE_LOW_DMA:
 831                 result = get_user(val, ip);
 832                 if (result)
 833                         return result;
 834                 if (val) {
 835                         sfp->low_dma = 1;
 836                         if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
 837                                 val = (int) sfp->reserve.bufflen;
 838                                 sg_remove_scat(&sfp->reserve);
 839                                 sg_build_reserve(sfp, val);
 840                         }
 841                 } else {
 842                         if (sdp->detached)
 843                                 return -ENODEV;
 844                         sfp->low_dma = sdp->device->host->unchecked_isa_dma;
 845                 }
 846                 return 0;
 847         case SG_GET_LOW_DMA:
 848                 return put_user((int) sfp->low_dma, ip);
 849         case SG_GET_SCSI_ID:
 850                 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
 851                         return -EFAULT;
 852                 else {
 853                         sg_scsi_id_t __user *sg_idp = p;
 854
 855                         if (sdp->detached)
 856                                 return -ENODEV;
 857                         __put_user((int) sdp->device->host->host_no,
 858                                    &sg_idp->host_no);
 859                         __put_user((int) sdp->device->channel,
 860                                    &sg_idp->channel);
 861                         __put_user((int) sdp->device->id, &sg_idp->scsi_id);
 862                         __put_user((int) sdp->device->lun, &sg_idp->lun);
 863                         __put_user((int) sdp->device->type, &sg_idp->scsi_type);
 864                         __put_user((short) sdp->device->host->cmd_per_lun,
 865                                    &sg_idp->h_cmd_per_lun);
 866                         __put_user((short) sdp->device->queue_depth,
 867                                    &sg_idp->d_queue_depth);
 868                         __put_user(0, &sg_idp->unused[0]);
 869                         __put_user(0, &sg_idp->unused[1]);
 870                         return 0;
 871                 }
 872         case SG_SET_FORCE_PACK_ID:
 873                 result = get_user(val, ip);
 874                 if (result)
 875                         return result;
 876                 sfp->force_packid = val ? 1 : 0;
 877                 return 0;
 878         case SG_GET_PACK_ID:
 879                 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
 880                         return -EFAULT;
 881                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 882                 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
 883                         if ((1 == srp->done) && (!srp->sg_io_owned)) {
 884                                 read_unlock_irqrestore(&sfp->rq_list_lock,
 885                                                        iflags);
 886                                 __put_user(srp->header.pack_id, ip);
 887                                 return 0;
 888                         }
 889                 }
 890                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 891                 __put_user(-1, ip);
 892                 return 0;
 893         case SG_GET_NUM_WAITING:
 894                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 895                 for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) {
 896                         if ((1 == srp->done) && (!srp->sg_io_owned))
 897                                 ++val;
 898                 }
 899                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 900                 return put_user(val, ip);
 901         case SG_GET_SG_TABLESIZE:
 902                 return put_user(sdp->sg_tablesize, ip);
 903         case SG_SET_RESERVED_SIZE:
 904                 result = get_user(val, ip);
 905                 if (result)
 906                         return result;
 907                 if (val < 0)
 908                         return -EINVAL;
 909                 val = min_t(int, val,
 910                             queue_max_sectors(sdp->device->request_queue) * 512);
 911                 if (val != sfp->reserve.bufflen) {
 912                         if (sg_res_in_use(sfp) || sfp->mmap_called)
 913                                 return -EBUSY;
 914                         sg_remove_scat(&sfp->reserve);
 915                         sg_build_reserve(sfp, val);
 916                 }
 917                 return 0;
 918         case SG_GET_RESERVED_SIZE:
 919                 val = min_t(int, sfp->reserve.bufflen,
 920                             queue_max_sectors(sdp->device->request_queue) * 512);
 921                 return put_user(val, ip);
 922         case SG_SET_COMMAND_Q:
 923                 result = get_user(val, ip);
 924                 if (result)
 925                         return result;
 926                 sfp->cmd_q = val ? 1 : 0;
 927                 return 0;
 928         case SG_GET_COMMAND_Q:
 929                 return put_user((int) sfp->cmd_q, ip);
 930         case SG_SET_KEEP_ORPHAN:
 931                 result = get_user(val, ip);
 932                 if (result)
 933                         return result;
 934                 sfp->keep_orphan = val;
 935                 return 0;
 936         case SG_GET_KEEP_ORPHAN:
 937                 return put_user((int) sfp->keep_orphan, ip);
 938         case SG_NEXT_CMD_LEN:
 939                 result = get_user(val, ip);
 940                 if (result)
 941                         return result;
 942                 sfp->next_cmd_len = (val > 0) ? val : 0;
 943                 return 0;
 944         case SG_GET_VERSION_NUM:
 945                 return put_user(sg_version_num, ip);
 946         case SG_GET_ACCESS_COUNT:
 947                 /* faked - we don't have a real access count anymore */
 948                 val = (sdp->device ? 1 : 0);
 949                 return put_user(val, ip);
 950         case SG_GET_REQUEST_TABLE:
 951                 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
 952                         return -EFAULT;
 953                 else {
 954                         sg_req_info_t *rinfo;
 955                         unsigned int ms;
 956
 957                         rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
 958                                                                 GFP_KERNEL);
 959                         if (!rinfo)
 960                                 return -ENOMEM;
 961                         read_lock_irqsave(&sfp->rq_list_lock, iflags);
 962                         for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE;
 963                              ++val, srp = srp ? srp->nextrp : srp) {
 964                                 memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
 965                                 if (srp) {
 966                                         rinfo[val].req_state = srp->done + 1;
 967                                         rinfo[val].problem =
 968                                             srp->header.masked_status &
 969                                             srp->header.host_status &
 970                                             srp->header.driver_status;
 971                                         if (srp->done)
 972                                                 rinfo[val].duration =
 973                                                         srp->header.duration;
 974                                         else {
 975                                                 ms = jiffies_to_msecs(jiffies);
 976                                                 rinfo[val].duration =
 977                                                     (ms > srp->header.duration) ?
 978                                                     (ms - srp->header.duration) : 0;
 979                                         }
 980                                         rinfo[val].orphan = srp->orphan;
 981                                         rinfo[val].sg_io_owned =
 982                                                         srp->sg_io_owned;
 983                                         rinfo[val].pack_id =
 984                                                         srp->header.pack_id;
 985                                         rinfo[val].usr_ptr =
 986                                                         srp->header.usr_ptr;
 987                                 }
 988                         }
 989                         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 990                         result = __copy_to_user(p, rinfo,
 991                                                 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
 992                         result = result ? -EFAULT : 0;
 993                         kfree(rinfo);
 994                         return result;
 995                 }
 996         case SG_EMULATED_HOST:
 997                 if (sdp->detached)
 998                         return -ENODEV;
 999                 return put_user(sdp->device->host->hostt->emulated, ip);
1000         case SG_SCSI_RESET:
1001                 if (sdp->detached)
1002                         return -ENODEV;
1003                 if (filp->f_flags & O_NONBLOCK) {
1004                         if (scsi_host_in_recovery(sdp->device->host))
1005                                 return -EBUSY;
1006                 } else if (!scsi_block_when_processing_errors(sdp->device))
1007                         return -EBUSY;
1008                 result = get_user(val, ip);
1009                 if (result)
1010                         return result;
1011                 if (SG_SCSI_RESET_NOTHING == val)
1012                         return 0;
1013                 switch (val) {
1014                 case SG_SCSI_RESET_DEVICE:
1015                         val = SCSI_TRY_RESET_DEVICE;
1016                         break;
1017                 case SG_SCSI_RESET_TARGET:
1018                         val = SCSI_TRY_RESET_TARGET;
1019                         break;
1020                 case SG_SCSI_RESET_BUS:
1021                         val = SCSI_TRY_RESET_BUS;
1022                         break;
1023                 case SG_SCSI_RESET_HOST:
1024                         val = SCSI_TRY_RESET_HOST;
1025                         break;
1026                 default:
1027                         return -EINVAL;
1028                 }
1029                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1030                         return -EACCES;
1031                 return (scsi_reset_provider(sdp->device, val) ==
1032                         SUCCESS) ? 0 : -EIO;
1033         case SCSI_IOCTL_SEND_COMMAND:
1034                 if (sdp->detached)
1035                         return -ENODEV;
1036                 if (read_only) {
1037                         unsigned char opcode = WRITE_6;
1038                         Scsi_Ioctl_Command __user *siocp = p;
1039
1040                         if (copy_from_user(&opcode, siocp->data, 1))
1041                                 return -EFAULT;
1042                         if (sg_allow_access(filp, &opcode))
1043                                 return -EPERM;
1044                 }
1045                 return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p);
1046         case SG_SET_DEBUG:
1047                 result = get_user(val, ip);
1048                 if (result)
1049                         return result;
1050                 sdp->sgdebug = (char) val;
1051                 return 0;
1052         case SCSI_IOCTL_GET_IDLUN:
1053         case SCSI_IOCTL_GET_BUS_NUMBER:
1054         case SCSI_IOCTL_PROBE_HOST:
1055         case SG_GET_TRANSFORM:
1056                 if (sdp->detached)
1057                         return -ENODEV;
1058                 return scsi_ioctl(sdp->device, cmd_in, p);
1059         case BLKSECTGET:
1060                 return put_user(queue_max_sectors(sdp->device->request_queue) * 512,
1061                                 ip);
1062         case BLKTRACESETUP:
1063                 return blk_trace_setup(sdp->device->request_queue,
1064                                        sdp->disk->disk_name,
1065                                        MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1066                                        NULL,
1067                                        (char *)arg);
1068         case BLKTRACESTART:
1069                 return blk_trace_startstop(sdp->device->request_queue, 1);
1070         case BLKTRACESTOP:
1071                 return blk_trace_startstop(sdp->device->request_queue, 0);
1072         case BLKTRACETEARDOWN:
1073                 return blk_trace_remove(sdp->device->request_queue);
1074         default:
1075                 if (read_only)
1076                         return -EPERM;  /* don't know so take safe approach */
1077                 return scsi_ioctl(sdp->device, cmd_in, p);
1078         }
1079 }
1080
1081 #ifdef CONFIG_COMPAT
1082 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1083 {
1084         Sg_device *sdp;
1085         Sg_fd *sfp;
1086         struct scsi_device *sdev;
1087
1088         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1089                 return -ENXIO;
1090
1091         sdev = sdp->device;
1092         if (sdev->host->hostt->compat_ioctl) {
1093                 int ret;
1094
1095                 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1096
1097                 return ret;
1098         }
1099
1100         return -ENOIOCTLCMD;
1101 }
1102 #endif
1103
1104 static unsigned int
1105 sg_poll(struct file *filp, poll_table * wait)
1106 {
1107         unsigned int res = 0;
1108         Sg_device *sdp;
1109         Sg_fd *sfp;
1110         Sg_request *srp;
1111         int count = 0;
1112         unsigned long iflags;
1113
1114         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))
1115             || sfp->closed)
1116                 return POLLERR;
1117         poll_wait(filp, &sfp->read_wait, wait);
1118         read_lock_irqsave(&sfp->rq_list_lock, iflags);
1119         for (srp = sfp->headrp; srp; srp = srp->nextrp) {
1120                 /* if any read waiting, flag it */
1121                 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1122                         res = POLLIN | POLLRDNORM;
1123                 ++count;
1124         }
1125         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1126
1127         if (sdp->detached)
1128                 res |= POLLHUP;
1129         else if (!sfp->cmd_q) {
1130                 if (0 == count)
1131                         res |= POLLOUT | POLLWRNORM;
1132         } else if (count < SG_MAX_QUEUE)
1133                 res |= POLLOUT | POLLWRNORM;
1134         SCSI_LOG_TIMEOUT(3, printk("sg_poll: %s, res=0x%x\n",
1135                                    sdp->disk->disk_name, (int) res));
1136         return res;
1137 }
1138
1139 static int
1140 sg_fasync(int fd, struct file *filp, int mode)
1141 {
1142         Sg_device *sdp;
1143         Sg_fd *sfp;
1144
1145         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1146                 return -ENXIO;
1147         SCSI_LOG_TIMEOUT(3, printk("sg_fasync: %s, mode=%d\n",
1148                                    sdp->disk->disk_name, mode));
1149
1150         return fasync_helper(fd, filp, mode, &sfp->async_qp);
1151 }
1152
1153 static int
1154 sg_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1155 {
1156         Sg_fd *sfp;
1157         unsigned long offset, len, sa;
1158         Sg_scatter_hold *rsv_schp;
1159         int k, length;
1160
1161         if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1162                 return VM_FAULT_SIGBUS;
1163         rsv_schp = &sfp->reserve;
1164         offset = vmf->pgoff << PAGE_SHIFT;
1165         if (offset >= rsv_schp->bufflen)
1166                 return VM_FAULT_SIGBUS;
1167         SCSI_LOG_TIMEOUT(3, printk("sg_vma_fault: offset=%lu, scatg=%d\n",
1168                                    offset, rsv_schp->k_use_sg));
1169         sa = vma->vm_start;
1170         length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1171         for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1172                 len = vma->vm_end - sa;
1173                 len = (len < length) ? len : length;
1174                 if (offset < len) {
1175                         struct page *page = nth_page(rsv_schp->pages[k],
1176                                                      offset >> PAGE_SHIFT);
1177                         get_page(page); /* increment page count */
1178                         vmf->page = page;
1179                         return 0; /* success */
1180                 }
1181                 sa += len;
1182                 offset -= len;
1183         }
1184
1185         return VM_FAULT_SIGBUS;
1186 }
1187
1188 static struct vm_operations_struct sg_mmap_vm_ops = {
1189         .fault = sg_vma_fault,
1190 };
1191
1192 static int
1193 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1194 {
1195         Sg_fd *sfp;
1196         unsigned long req_sz, len, sa;
1197         Sg_scatter_hold *rsv_schp;
1198         int k, length;
1199
1200         if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1201                 return -ENXIO;
1202         req_sz = vma->vm_end - vma->vm_start;
1203         SCSI_LOG_TIMEOUT(3, printk("sg_mmap starting, vm_start=%p, len=%d\n",
1204                                    (void *) vma->vm_start, (int) req_sz));
1205         if (vma->vm_pgoff)
1206                 return -EINVAL; /* want no offset */
1207         rsv_schp = &sfp->reserve;
1208         if (req_sz > rsv_schp->bufflen)
1209                 return -ENOMEM; /* cannot map more than reserved buffer */
1210
1211         sa = vma->vm_start;
1212         length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1213         for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1214                 len = vma->vm_end - sa;
1215                 len = (len < length) ? len : length;
1216                 sa += len;
1217         }
1218
1219         sfp->mmap_called = 1;
1220         vma->vm_flags |= VM_RESERVED;
1221         vma->vm_private_data = sfp;
1222         vma->vm_ops = &sg_mmap_vm_ops;
1223         return 0;
1224 }
1225
1226 static void sg_rq_end_io_usercontext(struct work_struct *work)
1227 {
1228         struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1229         struct sg_fd *sfp = srp->parentfp;
1230
1231         sg_finish_rem_req(srp);
1232         kref_put(&sfp->f_ref, sg_remove_sfp);
1233 }
1234
1235 /*
1236  * This function is a "bottom half" handler that is called by the mid
1237  * level when a command is completed (or has failed).
1238  */
1239 static void sg_rq_end_io(struct request *rq, int uptodate)
1240 {
1241         struct sg_request *srp = rq->end_io_data;
1242         Sg_device *sdp;
1243         Sg_fd *sfp;
1244         unsigned long iflags;
1245         unsigned int ms;
1246         char *sense;
1247         int result, resid, done = 1;
1248
1249         if (WARN_ON(srp->done != 0))
1250                 return;
1251
1252         sfp = srp->parentfp;
1253         if (WARN_ON(sfp == NULL))
1254                 return;
1255
1256         sdp = sfp->parentdp;
1257         if (unlikely(sdp->detached))
1258                 printk(KERN_INFO "sg_rq_end_io: device detached\n");
1259
1260         sense = rq->sense;
1261         result = rq->errors;
1262         resid = rq->resid_len;
1263
1264         SCSI_LOG_TIMEOUT(4, printk("sg_cmd_done: %s, pack_id=%d, res=0x%x\n",
1265                 sdp->disk->disk_name, srp->header.pack_id, result));
1266         srp->header.resid = resid;
1267         ms = jiffies_to_msecs(jiffies);
1268         srp->header.duration = (ms > srp->header.duration) ?
1269                                 (ms - srp->header.duration) : 0;
1270         if (0 != result) {
1271                 struct scsi_sense_hdr sshdr;
1272
1273                 srp->header.status = 0xff & result;
1274                 srp->header.masked_status = status_byte(result);
1275                 srp->header.msg_status = msg_byte(result);
1276                 srp->header.host_status = host_byte(result);
1277                 srp->header.driver_status = driver_byte(result);
1278                 if ((sdp->sgdebug > 0) &&
1279                     ((CHECK_CONDITION == srp->header.masked_status) ||
1280                      (COMMAND_TERMINATED == srp->header.masked_status)))
1281                         __scsi_print_sense("sg_cmd_done", sense,
1282                                            SCSI_SENSE_BUFFERSIZE);
1283
1284                 /* Following if statement is a patch supplied by Eric Youngdale */
1285                 if (driver_byte(result) != 0
1286                     && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1287                     && !scsi_sense_is_deferred(&sshdr)
1288                     && sshdr.sense_key == UNIT_ATTENTION
1289                     && sdp->device->removable) {
1290                         /* Detected possible disc change. Set the bit - this */
1291                         /* may be used if there are filesystems using this device */
1292                         sdp->device->changed = 1;
1293                 }
1294         }
1295         /* Rely on write phase to clean out srp status values, so no "else" */
1296
1297         write_lock_irqsave(&sfp->rq_list_lock, iflags);
1298         if (unlikely(srp->orphan)) {
1299                 if (sfp->keep_orphan)
1300                         srp->sg_io_owned = 0;
1301                 else
1302                         done = 0;
1303         }
1304         srp->done = done;
1305         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1306
1307         if (likely(done)) {
1308                 /* Now wake up any sg_read() that is waiting for this
1309                  * packet.
1310                  */
1311                 wake_up_interruptible(&sfp->read_wait);
1312                 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1313                 kref_put(&sfp->f_ref, sg_remove_sfp);
1314         } else {
1315                 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1316                 schedule_work(&srp->ew.work);
1317         }
1318 }
1319
1320 static struct file_operations sg_fops = {
1321         .owner = THIS_MODULE,
1322         .read = sg_read,
1323         .write = sg_write,
1324         .poll = sg_poll,
1325         .ioctl = sg_ioctl,
1326 #ifdef CONFIG_COMPAT
1327         .compat_ioctl = sg_compat_ioctl,
1328 #endif
1329         .open = sg_open,
1330         .mmap = sg_mmap,
1331         .release = sg_release,
1332         .fasync = sg_fasync,
1333 };
1334
1335 static struct class *sg_sysfs_class;
1336
1337 static int sg_sysfs_valid = 0;
1338
1339 static Sg_device *sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1340 {
1341         struct request_queue *q = scsidp->request_queue;
1342         Sg_device *sdp;
1343         unsigned long iflags;
1344         int error;
1345         u32 k;
1346
1347         sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1348         if (!sdp) {
1349                 printk(KERN_WARNING "kmalloc Sg_device failure\n");
1350                 return ERR_PTR(-ENOMEM);
1351         }
1352
1353         if (!idr_pre_get(&sg_index_idr, GFP_KERNEL)) {
1354                 printk(KERN_WARNING "idr expansion Sg_device failure\n");
1355                 error = -ENOMEM;
1356                 goto out;
1357         }
1358
1359         write_lock_irqsave(&sg_index_lock, iflags);
1360
1361         error = idr_get_new(&sg_index_idr, sdp, &k);
1362         if (error) {
1363                 write_unlock_irqrestore(&sg_index_lock, iflags);
1364                 printk(KERN_WARNING "idr allocation Sg_device failure: %d\n",
1365                        error);
1366                 goto out;
1367         }
1368
1369         if (unlikely(k >= SG_MAX_DEVS))
1370                 goto overflow;
1371
1372         SCSI_LOG_TIMEOUT(3, printk("sg_alloc: dev=%d \n", k));
1373         sprintf(disk->disk_name, "sg%d", k);
1374         disk->first_minor = k;
1375         sdp->disk = disk;
1376         sdp->device = scsidp;
1377         INIT_LIST_HEAD(&sdp->sfds);
1378         init_waitqueue_head(&sdp->o_excl_wait);
1379         sdp->sg_tablesize = min(queue_max_hw_segments(q),
1380                                 queue_max_phys_segments(q));
1381         sdp->index = k;
1382         kref_init(&sdp->d_ref);
1383
1384         write_unlock_irqrestore(&sg_index_lock, iflags);
1385
1386         error = 0;
1387  out:
1388         if (error) {
1389                 kfree(sdp);
1390                 return ERR_PTR(error);
1391         }
1392         return sdp;
1393
1394  overflow:
1395         idr_remove(&sg_index_idr, k);
1396         write_unlock_irqrestore(&sg_index_lock, iflags);
1397         sdev_printk(KERN_WARNING, scsidp,
1398                     "Unable to attach sg device type=%d, minor "
1399                     "number exceeds %d\n", scsidp->type, SG_MAX_DEVS - 1);
1400         error = -ENODEV;
1401         goto out;
1402 }
1403
1404 static int
1405 sg_add(struct device *cl_dev, struct class_interface *cl_intf)
1406 {
1407         struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1408         struct gendisk *disk;
1409         Sg_device *sdp = NULL;
1410         struct cdev * cdev = NULL;
1411         int error;
1412         unsigned long iflags;
1413
1414         disk = alloc_disk(1);
1415         if (!disk) {
1416                 printk(KERN_WARNING "alloc_disk failed\n");
1417                 return -ENOMEM;
1418         }
1419         disk->major = SCSI_GENERIC_MAJOR;
1420
1421         error = -ENOMEM;
1422         cdev = cdev_alloc();
1423         if (!cdev) {
1424                 printk(KERN_WARNING "cdev_alloc failed\n");
1425                 goto out;
1426         }
1427         cdev->owner = THIS_MODULE;
1428         cdev->ops = &sg_fops;
1429
1430         sdp = sg_alloc(disk, scsidp);
1431         if (IS_ERR(sdp)) {
1432                 printk(KERN_WARNING "sg_alloc failed\n");
1433                 error = PTR_ERR(sdp);
1434                 goto out;
1435         }
1436
1437         error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1438         if (error)
1439                 goto cdev_add_err;
1440
1441         sdp->cdev = cdev;
1442         if (sg_sysfs_valid) {
1443                 struct device *sg_class_member;
1444
1445                 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1446                                                 MKDEV(SCSI_GENERIC_MAJOR,
1447                                                       sdp->index),
1448                                                 sdp, "%s", disk->disk_name);
1449                 if (IS_ERR(sg_class_member)) {
1450                         printk(KERN_ERR "sg_add: "
1451                                "device_create failed\n");
1452                         error = PTR_ERR(sg_class_member);
1453                         goto cdev_add_err;
1454                 }
1455                 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1456                                           &sg_class_member->kobj, "generic");
1457                 if (error)
1458                         printk(KERN_ERR "sg_add: unable to make symlink "
1459                                         "'generic' back to sg%d\n", sdp->index);
1460         } else
1461                 printk(KERN_WARNING "sg_add: sg_sys Invalid\n");
1462
1463         sdev_printk(KERN_NOTICE, scsidp,
1464                     "Attached scsi generic sg%d type %d\n", sdp->index,
1465                     scsidp->type);
1466
1467         dev_set_drvdata(cl_dev, sdp);
1468
1469         return 0;
1470
1471 cdev_add_err:
1472         write_lock_irqsave(&sg_index_lock, iflags);
1473         idr_remove(&sg_index_idr, sdp->index);
1474         write_unlock_irqrestore(&sg_index_lock, iflags);
1475         kfree(sdp);
1476
1477 out:
1478         put_disk(disk);
1479         if (cdev)
1480                 cdev_del(cdev);
1481         return error;
1482 }
1483
1484 static void sg_device_destroy(struct kref *kref)
1485 {
1486         struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1487         unsigned long flags;
1488
1489         /* CAUTION!  Note that the device can still be found via idr_find()
1490          * even though the refcount is 0.  Therefore, do idr_remove() BEFORE
1491          * any other cleanup.
1492          */
1493
1494         write_lock_irqsave(&sg_index_lock, flags);
1495         idr_remove(&sg_index_idr, sdp->index);
1496         write_unlock_irqrestore(&sg_index_lock, flags);
1497
1498         SCSI_LOG_TIMEOUT(3,
1499                 printk("sg_device_destroy: %s\n",
1500                         sdp->disk->disk_name));
1501
1502         put_disk(sdp->disk);
1503         kfree(sdp);
1504 }
1505
1506 static void sg_remove(struct device *cl_dev, struct class_interface *cl_intf)
1507 {
1508         struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1509         Sg_device *sdp = dev_get_drvdata(cl_dev);
1510         unsigned long iflags;
1511         Sg_fd *sfp;
1512
1513         if (!sdp || sdp->detached)
1514                 return;
1515
1516         SCSI_LOG_TIMEOUT(3, printk("sg_remove: %s\n", sdp->disk->disk_name));
1517
1518         /* Need a write lock to set sdp->detached. */
1519         write_lock_irqsave(&sg_index_lock, iflags);
1520         sdp->detached = 1;
1521         list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1522                 wake_up_interruptible(&sfp->read_wait);
1523                 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1524         }
1525         write_unlock_irqrestore(&sg_index_lock, iflags);
1526
1527         sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1528         device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1529         cdev_del(sdp->cdev);
1530         sdp->cdev = NULL;
1531
1532         sg_put_dev(sdp);
1533 }
1534
1535 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1536 module_param_named(def_reserved_size, def_reserved_size, int,
1537                    S_IRUGO | S_IWUSR);
1538 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1539
1540 MODULE_AUTHOR("Douglas Gilbert");
1541 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1542 MODULE_LICENSE("GPL");
1543 MODULE_VERSION(SG_VERSION_STR);
1544 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1545
1546 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1547                 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1548 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1549 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1550
1551 static int __init
1552 init_sg(void)
1553 {
1554         int rc;
1555
1556         if (scatter_elem_sz < PAGE_SIZE) {
1557                 scatter_elem_sz = PAGE_SIZE;
1558                 scatter_elem_sz_prev = scatter_elem_sz;
1559         }
1560         if (def_reserved_size >= 0)
1561                 sg_big_buff = def_reserved_size;
1562         else
1563                 def_reserved_size = sg_big_buff;
1564
1565         rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1566                                     SG_MAX_DEVS, "sg");
1567         if (rc)
1568                 return rc;
1569         sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1570         if ( IS_ERR(sg_sysfs_class) ) {
1571                 rc = PTR_ERR(sg_sysfs_class);
1572                 goto err_out;
1573         }
1574         sg_sysfs_valid = 1;
1575         rc = scsi_register_interface(&sg_interface);
1576         if (0 == rc) {
1577 #ifdef CONFIG_SCSI_PROC_FS
1578                 sg_proc_init();
1579 #endif                          /* CONFIG_SCSI_PROC_FS */
1580                 return 0;
1581         }
1582         class_destroy(sg_sysfs_class);
1583 err_out:
1584         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1585         return rc;
1586 }
1587
1588 static void __exit
1589 exit_sg(void)
1590 {
1591 #ifdef CONFIG_SCSI_PROC_FS
1592         sg_proc_cleanup();
1593 #endif                          /* CONFIG_SCSI_PROC_FS */
1594         scsi_unregister_interface(&sg_interface);
1595         class_destroy(sg_sysfs_class);
1596         sg_sysfs_valid = 0;
1597         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1598                                  SG_MAX_DEVS);
1599         idr_destroy(&sg_index_idr);
1600 }
1601
1602 static int sg_start_req(Sg_request *srp, unsigned char *cmd)
1603 {
1604         int res;
1605         struct request *rq;
1606         Sg_fd *sfp = srp->parentfp;
1607         sg_io_hdr_t *hp = &srp->header;
1608         int dxfer_len = (int) hp->dxfer_len;
1609         int dxfer_dir = hp->dxfer_direction;
1610         unsigned int iov_count = hp->iovec_count;
1611         Sg_scatter_hold *req_schp = &srp->data;
1612         Sg_scatter_hold *rsv_schp = &sfp->reserve;
1613         struct request_queue *q = sfp->parentdp->device->request_queue;
1614         struct rq_map_data *md, map_data;
1615         int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
1616
1617         SCSI_LOG_TIMEOUT(4, printk(KERN_INFO "sg_start_req: dxfer_len=%d\n",
1618                                    dxfer_len));
1619
1620         rq = blk_get_request(q, rw, GFP_ATOMIC);
1621         if (!rq)
1622                 return -ENOMEM;
1623
1624         memcpy(rq->cmd, cmd, hp->cmd_len);
1625
1626         rq->cmd_len = hp->cmd_len;
1627         rq->cmd_type = REQ_TYPE_BLOCK_PC;
1628
1629         srp->rq = rq;
1630         rq->end_io_data = srp;
1631         rq->sense = srp->sense_b;
1632         rq->retries = SG_DEFAULT_RETRIES;
1633
1634         if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1635                 return 0;
1636
1637         if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1638             dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1639             !sfp->parentdp->device->host->unchecked_isa_dma &&
1640             blk_rq_aligned(q, hp->dxferp, dxfer_len))
1641                 md = NULL;
1642         else
1643                 md = &map_data;
1644
1645         if (md) {
1646                 if (!sg_res_in_use(sfp) && dxfer_len <= rsv_schp->bufflen)
1647                         sg_link_reserve(sfp, srp, dxfer_len);
1648                 else {
1649                         res = sg_build_indirect(req_schp, sfp, dxfer_len);
1650                         if (res)
1651                                 return res;
1652                 }
1653
1654                 md->pages = req_schp->pages;
1655                 md->page_order = req_schp->page_order;
1656                 md->nr_entries = req_schp->k_use_sg;
1657                 md->offset = 0;
1658                 md->null_mapped = hp->dxferp ? 0 : 1;
1659                 if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1660                         md->from_user = 1;
1661                 else
1662                         md->from_user = 0;
1663         }
1664
1665         if (iov_count) {
1666                 int len, size = sizeof(struct sg_iovec) * iov_count;
1667                 struct iovec *iov;
1668
1669                 iov = kmalloc(size, GFP_ATOMIC);
1670                 if (!iov)
1671                         return -ENOMEM;
1672
1673                 if (copy_from_user(iov, hp->dxferp, size)) {
1674                         kfree(iov);
1675                         return -EFAULT;
1676                 }
1677
1678                 len = iov_length(iov, iov_count);
1679                 if (hp->dxfer_len < len) {
1680                         iov_count = iov_shorten(iov, iov_count, hp->dxfer_len);
1681                         len = hp->dxfer_len;
1682                 }
1683
1684                 res = blk_rq_map_user_iov(q, rq, md, (struct sg_iovec *)iov,
1685                                           iov_count,
1686                                           len, GFP_ATOMIC);
1687                 kfree(iov);
1688         } else
1689                 res = blk_rq_map_user(q, rq, md, hp->dxferp,
1690                                       hp->dxfer_len, GFP_ATOMIC);
1691
1692         if (!res) {
1693                 srp->bio = rq->bio;
1694
1695                 if (!md) {
1696                         req_schp->dio_in_use = 1;
1697                         hp->info |= SG_INFO_DIRECT_IO;
1698                 }
1699         }
1700         return res;
1701 }
1702
1703 static int sg_finish_rem_req(Sg_request * srp)
1704 {
1705         int ret = 0;
1706
1707         Sg_fd *sfp = srp->parentfp;
1708         Sg_scatter_hold *req_schp = &srp->data;
1709
1710         SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n", (int) srp->res_used));
1711         if (srp->res_used)
1712                 sg_unlink_reserve(sfp, srp);
1713         else
1714                 sg_remove_scat(req_schp);
1715
1716         if (srp->rq) {
1717                 if (srp->bio)
1718                         ret = blk_rq_unmap_user(srp->bio);
1719
1720                 blk_put_request(srp->rq);
1721         }
1722
1723         sg_remove_request(sfp, srp);
1724
1725         return ret;
1726 }
1727
1728 static int
1729 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1730 {
1731         int sg_bufflen = tablesize * sizeof(struct page *);
1732         gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1733
1734         schp->pages = kzalloc(sg_bufflen, gfp_flags);
1735         if (!schp->pages)
1736                 return -ENOMEM;
1737         schp->sglist_len = sg_bufflen;
1738         return tablesize;       /* number of scat_gath elements allocated */
1739 }
1740
1741 static int
1742 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1743 {
1744         int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1745         int sg_tablesize = sfp->parentdp->sg_tablesize;
1746         int blk_size = buff_size, order;
1747         gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
1748
1749         if (blk_size < 0)
1750                 return -EFAULT;
1751         if (0 == blk_size)
1752                 ++blk_size;     /* don't know why */
1753         /* round request up to next highest SG_SECTOR_SZ byte boundary */
1754         blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1755         SCSI_LOG_TIMEOUT(4, printk("sg_build_indirect: buff_size=%d, blk_size=%d\n",
1756                                    buff_size, blk_size));
1757
1758         /* N.B. ret_sz carried into this block ... */
1759         mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1760         if (mx_sc_elems < 0)
1761                 return mx_sc_elems;     /* most likely -ENOMEM */
1762
1763         num = scatter_elem_sz;
1764         if (unlikely(num != scatter_elem_sz_prev)) {
1765                 if (num < PAGE_SIZE) {
1766                         scatter_elem_sz = PAGE_SIZE;
1767                         scatter_elem_sz_prev = PAGE_SIZE;
1768                 } else
1769                         scatter_elem_sz_prev = num;
1770         }
1771
1772         if (sfp->low_dma)
1773                 gfp_mask |= GFP_DMA;
1774
1775         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1776                 gfp_mask |= __GFP_ZERO;
1777
1778         order = get_order(num);
1779 retry:
1780         ret_sz = 1 << (PAGE_SHIFT + order);
1781
1782         for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1783              k++, rem_sz -= ret_sz) {
1784
1785                 num = (rem_sz > scatter_elem_sz_prev) ?
1786                         scatter_elem_sz_prev : rem_sz;
1787
1788                 schp->pages[k] = alloc_pages(gfp_mask, order);
1789                 if (!schp->pages[k])
1790                         goto out;
1791
1792                 if (num == scatter_elem_sz_prev) {
1793                         if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1794                                 scatter_elem_sz = ret_sz;
1795                                 scatter_elem_sz_prev = ret_sz;
1796                         }
1797                 }
1798
1799                 SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k=%d, num=%d, "
1800                                  "ret_sz=%d\n", k, num, ret_sz));
1801         }               /* end of for loop */
1802
1803         schp->page_order = order;
1804         schp->k_use_sg = k;
1805         SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, "
1806                          "rem_sz=%d\n", k, rem_sz));
1807
1808         schp->bufflen = blk_size;
1809         if (rem_sz > 0) /* must have failed */
1810                 return -ENOMEM;
1811         return 0;
1812 out:
1813         for (i = 0; i < k; i++)
1814                 __free_pages(schp->pages[k], order);
1815
1816         if (--order >= 0)
1817                 goto retry;
1818
1819         return -ENOMEM;
1820 }
1821
1822 static void
1823 sg_remove_scat(Sg_scatter_hold * schp)
1824 {
1825         SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1826         if (schp->pages && schp->sglist_len > 0) {
1827                 if (!schp->dio_in_use) {
1828                         int k;
1829
1830                         for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1831                                 SCSI_LOG_TIMEOUT(5, printk(
1832                                     "sg_remove_scat: k=%d, pg=0x%p\n",
1833                                     k, schp->pages[k]));
1834                                 __free_pages(schp->pages[k], schp->page_order);
1835                         }
1836
1837                         kfree(schp->pages);
1838                 }
1839         }
1840         memset(schp, 0, sizeof (*schp));
1841 }
1842
1843 static int
1844 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1845 {
1846         Sg_scatter_hold *schp = &srp->data;
1847         int k, num;
1848
1849         SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n",
1850                                    num_read_xfer));
1851         if ((!outp) || (num_read_xfer <= 0))
1852                 return 0;
1853
1854         num = 1 << (PAGE_SHIFT + schp->page_order);
1855         for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1856                 if (num > num_read_xfer) {
1857                         if (__copy_to_user(outp, page_address(schp->pages[k]),
1858                                            num_read_xfer))
1859                                 return -EFAULT;
1860                         break;
1861                 } else {
1862                         if (__copy_to_user(outp, page_address(schp->pages[k]),
1863                                            num))
1864                                 return -EFAULT;
1865                         num_read_xfer -= num;
1866                         if (num_read_xfer <= 0)
1867                                 break;
1868                         outp += num;
1869                 }
1870         }
1871
1872         return 0;
1873 }
1874
1875 static void
1876 sg_build_reserve(Sg_fd * sfp, int req_size)
1877 {
1878         Sg_scatter_hold *schp = &sfp->reserve;
1879
1880         SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
1881         do {
1882                 if (req_size < PAGE_SIZE)
1883                         req_size = PAGE_SIZE;
1884                 if (0 == sg_build_indirect(schp, sfp, req_size))
1885                         return;
1886                 else
1887                         sg_remove_scat(schp);
1888                 req_size >>= 1; /* divide by 2 */
1889         } while (req_size > (PAGE_SIZE / 2));
1890 }
1891
1892 static void
1893 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
1894 {
1895         Sg_scatter_hold *req_schp = &srp->data;
1896         Sg_scatter_hold *rsv_schp = &sfp->reserve;
1897         int k, num, rem;
1898
1899         srp->res_used = 1;
1900         SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
1901         rem = size;
1902
1903         num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1904         for (k = 0; k < rsv_schp->k_use_sg; k++) {
1905                 if (rem <= num) {
1906                         req_schp->k_use_sg = k + 1;
1907                         req_schp->sglist_len = rsv_schp->sglist_len;
1908                         req_schp->pages = rsv_schp->pages;
1909
1910                         req_schp->bufflen = size;
1911                         req_schp->page_order = rsv_schp->page_order;
1912                         break;
1913                 } else
1914                         rem -= num;
1915         }
1916
1917         if (k >= rsv_schp->k_use_sg)
1918                 SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
1919 }
1920
1921 static void
1922 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
1923 {
1924         Sg_scatter_hold *req_schp = &srp->data;
1925
1926         SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->k_use_sg=%d\n",
1927                                    (int) req_schp->k_use_sg));
1928         req_schp->k_use_sg = 0;
1929         req_schp->bufflen = 0;
1930         req_schp->pages = NULL;
1931         req_schp->page_order = 0;
1932         req_schp->sglist_len = 0;
1933         sfp->save_scat_len = 0;
1934         srp->res_used = 0;
1935 }
1936
1937 static Sg_request *
1938 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
1939 {
1940         Sg_request *resp;
1941         unsigned long iflags;
1942
1943         write_lock_irqsave(&sfp->rq_list_lock, iflags);
1944         for (resp = sfp->headrp; resp; resp = resp->nextrp) {
1945                 /* look for requests that are ready + not SG_IO owned */
1946                 if ((1 == resp->done) && (!resp->sg_io_owned) &&
1947                     ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
1948                         resp->done = 2; /* guard against other readers */
1949                         break;
1950                 }
1951         }
1952         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1953         return resp;
1954 }
1955
1956 /* always adds to end of list */
1957 static Sg_request *
1958 sg_add_request(Sg_fd * sfp)
1959 {
1960         int k;
1961         unsigned long iflags;
1962         Sg_request *resp;
1963         Sg_request *rp = sfp->req_arr;
1964
1965         write_lock_irqsave(&sfp->rq_list_lock, iflags);
1966         resp = sfp->headrp;
1967         if (!resp) {
1968                 memset(rp, 0, sizeof (Sg_request));
1969                 rp->parentfp = sfp;
1970                 resp = rp;
1971                 sfp->headrp = resp;
1972         } else {
1973                 if (0 == sfp->cmd_q)
1974                         resp = NULL;    /* command queuing disallowed */
1975                 else {
1976                         for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
1977                                 if (!rp->parentfp)
1978                                         break;
1979                         }
1980                         if (k < SG_MAX_QUEUE) {
1981                                 memset(rp, 0, sizeof (Sg_request));
1982                                 rp->parentfp = sfp;
1983                                 while (resp->nextrp)
1984                                         resp = resp->nextrp;
1985                                 resp->nextrp = rp;
1986                                 resp = rp;
1987                         } else
1988                                 resp = NULL;
1989                 }
1990         }
1991         if (resp) {
1992                 resp->nextrp = NULL;
1993                 resp->header.duration = jiffies_to_msecs(jiffies);
1994         }
1995         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1996         return resp;
1997 }
1998
1999 /* Return of 1 for found; 0 for not found */
2000 static int
2001 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2002 {
2003         Sg_request *prev_rp;
2004         Sg_request *rp;
2005         unsigned long iflags;
2006         int res = 0;
2007
2008         if ((!sfp) || (!srp) || (!sfp->headrp))
2009                 return res;
2010         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2011         prev_rp = sfp->headrp;
2012         if (srp == prev_rp) {
2013                 sfp->headrp = prev_rp->nextrp;
2014                 prev_rp->parentfp = NULL;
2015                 res = 1;
2016         } else {
2017                 while ((rp = prev_rp->nextrp)) {
2018                         if (srp == rp) {
2019                                 prev_rp->nextrp = rp->nextrp;
2020                                 rp->parentfp = NULL;
2021                                 res = 1;
2022                                 break;
2023                         }
2024                         prev_rp = rp;
2025                 }
2026         }
2027         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2028         return res;
2029 }
2030
2031 static Sg_fd *
2032 sg_add_sfp(Sg_device * sdp, int dev)
2033 {
2034         Sg_fd *sfp;
2035         unsigned long iflags;
2036         int bufflen;
2037
2038         sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2039         if (!sfp)
2040                 return NULL;
2041
2042         init_waitqueue_head(&sfp->read_wait);
2043         rwlock_init(&sfp->rq_list_lock);
2044
2045         kref_init(&sfp->f_ref);
2046         sfp->timeout = SG_DEFAULT_TIMEOUT;
2047         sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2048         sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2049         sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
2050             sdp->device->host->unchecked_isa_dma : 1;
2051         sfp->cmd_q = SG_DEF_COMMAND_Q;
2052         sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2053         sfp->parentdp = sdp;
2054         write_lock_irqsave(&sg_index_lock, iflags);
2055         list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2056         write_unlock_irqrestore(&sg_index_lock, iflags);
2057         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));
2058         if (unlikely(sg_big_buff != def_reserved_size))
2059                 sg_big_buff = def_reserved_size;
2060
2061         bufflen = min_t(int, sg_big_buff,
2062                         queue_max_sectors(sdp->device->request_queue) * 512);
2063         sg_build_reserve(sfp, bufflen);
2064         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp:   bufflen=%d, k_use_sg=%d\n",
2065                            sfp->reserve.bufflen, sfp->reserve.k_use_sg));
2066
2067         kref_get(&sdp->d_ref);
2068         __module_get(THIS_MODULE);
2069         return sfp;
2070 }
2071
2072 static void sg_remove_sfp_usercontext(struct work_struct *work)
2073 {
2074         struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2075         struct sg_device *sdp = sfp->parentdp;
2076
2077         /* Cleanup any responses which were never read(). */
2078         while (sfp->headrp)
2079                 sg_finish_rem_req(sfp->headrp);
2080
2081         if (sfp->reserve.bufflen > 0) {
2082                 SCSI_LOG_TIMEOUT(6,
2083                         printk("sg_remove_sfp:    bufflen=%d, k_use_sg=%d\n",
2084                                 (int) sfp->reserve.bufflen,
2085                                 (int) sfp->reserve.k_use_sg));
2086                 sg_remove_scat(&sfp->reserve);
2087         }
2088
2089         SCSI_LOG_TIMEOUT(6,
2090                 printk("sg_remove_sfp: %s, sfp=0x%p\n",
2091                         sdp->disk->disk_name,
2092                         sfp));
2093         kfree(sfp);
2094
2095         scsi_device_put(sdp->device);
2096         sg_put_dev(sdp);
2097         module_put(THIS_MODULE);
2098 }
2099
2100 static void sg_remove_sfp(struct kref *kref)
2101 {
2102         struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2103         struct sg_device *sdp = sfp->parentdp;
2104         unsigned long iflags;
2105
2106         write_lock_irqsave(&sg_index_lock, iflags);
2107         list_del(&sfp->sfd_siblings);
2108         write_unlock_irqrestore(&sg_index_lock, iflags);
2109         wake_up_interruptible(&sdp->o_excl_wait);
2110
2111         INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2112         schedule_work(&sfp->ew.work);
2113 }
2114
2115 static int
2116 sg_res_in_use(Sg_fd * sfp)
2117 {
2118         const Sg_request *srp;
2119         unsigned long iflags;
2120
2121         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2122         for (srp = sfp->headrp; srp; srp = srp->nextrp)
2123                 if (srp->res_used)
2124                         break;
2125         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2126         return srp ? 1 : 0;
2127 }
2128
2129 #ifdef CONFIG_SCSI_PROC_FS
2130 static int
2131 sg_idr_max_id(int id, void *p, void *data)
2132 {
2133         int *k = data;
2134
2135         if (*k < id)
2136                 *k = id;
2137
2138         return 0;
2139 }
2140
2141 static int
2142 sg_last_dev(void)
2143 {
2144         int k = -1;
2145         unsigned long iflags;
2146
2147         read_lock_irqsave(&sg_index_lock, iflags);
2148         idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2149         read_unlock_irqrestore(&sg_index_lock, iflags);
2150         return k + 1;           /* origin 1 */
2151 }
2152 #endif
2153
2154 /* must be called with sg_index_lock held */
2155 static Sg_device *sg_lookup_dev(int dev)
2156 {
2157         return idr_find(&sg_index_idr, dev);
2158 }
2159
2160 static Sg_device *sg_get_dev(int dev)
2161 {
2162         struct sg_device *sdp;
2163         unsigned long flags;
2164
2165         read_lock_irqsave(&sg_index_lock, flags);
2166         sdp = sg_lookup_dev(dev);
2167         if (!sdp)
2168                 sdp = ERR_PTR(-ENXIO);
2169         else if (sdp->detached) {
2170                 /* If sdp->detached, then the refcount may already be 0, in
2171                  * which case it would be a bug to do kref_get().
2172                  */
2173                 sdp = ERR_PTR(-ENODEV);
2174         } else
2175                 kref_get(&sdp->d_ref);
2176         read_unlock_irqrestore(&sg_index_lock, flags);
2177
2178         return sdp;
2179 }
2180
2181 static void sg_put_dev(struct sg_device *sdp)
2182 {
2183         kref_put(&sdp->d_ref, sg_device_destroy);
2184 }
2185
2186 #ifdef CONFIG_SCSI_PROC_FS
2187
2188 static struct proc_dir_entry *sg_proc_sgp = NULL;
2189
2190 static char sg_proc_sg_dirname[] = "scsi/sg";
2191
2192 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2193
2194 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2195 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2196                                   size_t count, loff_t *off);
2197 static struct file_operations adio_fops = {
2198         /* .owner, .read and .llseek added in sg_proc_init() */
2199         .open = sg_proc_single_open_adio,
2200         .write = sg_proc_write_adio,
2201         .release = single_release,
2202 };
2203
2204 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2205 static ssize_t sg_proc_write_dressz(struct file *filp,
2206                 const char __user *buffer, size_t count, loff_t *off);
2207 static struct file_operations dressz_fops = {
2208         .open = sg_proc_single_open_dressz,
2209         .write = sg_proc_write_dressz,
2210         .release = single_release,
2211 };
2212
2213 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2214 static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2215 static struct file_operations version_fops = {
2216         .open = sg_proc_single_open_version,
2217         .release = single_release,
2218 };
2219
2220 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2221 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2222 static struct file_operations devhdr_fops = {
2223         .open = sg_proc_single_open_devhdr,
2224         .release = single_release,
2225 };
2226
2227 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2228 static int sg_proc_open_dev(struct inode *inode, struct file *file);
2229 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2230 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2231 static void dev_seq_stop(struct seq_file *s, void *v);
2232 static struct file_operations dev_fops = {
2233         .open = sg_proc_open_dev,
2234         .release = seq_release,
2235 };
2236 static struct seq_operations dev_seq_ops = {
2237         .start = dev_seq_start,
2238         .next  = dev_seq_next,
2239         .stop  = dev_seq_stop,
2240         .show  = sg_proc_seq_show_dev,
2241 };
2242
2243 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2244 static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2245 static struct file_operations devstrs_fops = {
2246         .open = sg_proc_open_devstrs,
2247         .release = seq_release,
2248 };
2249 static struct seq_operations devstrs_seq_ops = {
2250         .start = dev_seq_start,
2251         .next  = dev_seq_next,
2252         .stop  = dev_seq_stop,
2253         .show  = sg_proc_seq_show_devstrs,
2254 };
2255
2256 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2257 static int sg_proc_open_debug(struct inode *inode, struct file *file);
2258 static struct file_operations debug_fops = {
2259         .open = sg_proc_open_debug,
2260         .release = seq_release,
2261 };
2262 static struct seq_operations debug_seq_ops = {
2263         .start = dev_seq_start,
2264         .next  = dev_seq_next,
2265         .stop  = dev_seq_stop,
2266         .show  = sg_proc_seq_show_debug,
2267 };
2268
2269
2270 struct sg_proc_leaf {
2271         const char * name;
2272         struct file_operations * fops;
2273 };
2274
2275 static struct sg_proc_leaf sg_proc_leaf_arr[] = {
2276         {"allow_dio", &adio_fops},
2277         {"debug", &debug_fops},
2278         {"def_reserved_size", &dressz_fops},
2279         {"device_hdr", &devhdr_fops},
2280         {"devices", &dev_fops},
2281         {"device_strs", &devstrs_fops},
2282         {"version", &version_fops}
2283 };
2284
2285 static int
2286 sg_proc_init(void)
2287 {
2288         int k, mask;
2289         int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2290         struct sg_proc_leaf * leaf;
2291
2292         sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2293         if (!sg_proc_sgp)
2294                 return 1;
2295         for (k = 0; k < num_leaves; ++k) {
2296                 leaf = &sg_proc_leaf_arr[k];
2297                 mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2298                 leaf->fops->owner = THIS_MODULE;
2299                 leaf->fops->read = seq_read;
2300                 leaf->fops->llseek = seq_lseek;
2301                 proc_create(leaf->name, mask, sg_proc_sgp, leaf->fops);
2302         }
2303         return 0;
2304 }
2305
2306 static void
2307 sg_proc_cleanup(void)
2308 {
2309         int k;
2310         int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2311
2312         if (!sg_proc_sgp)
2313                 return;
2314         for (k = 0; k < num_leaves; ++k)
2315                 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2316         remove_proc_entry(sg_proc_sg_dirname, NULL);
2317 }
2318
2319
2320 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2321 {
2322         seq_printf(s, "%d\n", *((int *)s->private));
2323         return 0;
2324 }
2325
2326 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2327 {
2328         return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2329 }
2330
2331 static ssize_t
2332 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2333                    size_t count, loff_t *off)
2334 {
2335         int num;
2336         char buff[11];
2337
2338         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2339                 return -EACCES;
2340         num = (count < 10) ? count : 10;
2341         if (copy_from_user(buff, buffer, num))
2342                 return -EFAULT;
2343         buff[num] = '\0';
2344         sg_allow_dio = simple_strtoul(buff, NULL, 10) ? 1 : 0;
2345         return count;
2346 }
2347
2348 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2349 {
2350         return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2351 }
2352
2353 static ssize_t
2354 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2355                      size_t count, loff_t *off)
2356 {
2357         int num;
2358         unsigned long k = ULONG_MAX;
2359         char buff[11];
2360
2361         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2362                 return -EACCES;
2363         num = (count < 10) ? count : 10;
2364         if (copy_from_user(buff, buffer, num))
2365                 return -EFAULT;
2366         buff[num] = '\0';
2367         k = simple_strtoul(buff, NULL, 10);
2368         if (k <= 1048576) {     /* limit "big buff" to 1 MB */
2369                 sg_big_buff = k;
2370                 return count;
2371         }
2372         return -ERANGE;
2373 }
2374
2375 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2376 {
2377         seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2378                    sg_version_date);
2379         return 0;
2380 }
2381
2382 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2383 {
2384         return single_open(file, sg_proc_seq_show_version, NULL);
2385 }
2386
2387 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2388 {
2389         seq_printf(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\t"
2390                    "online\n");
2391         return 0;
2392 }
2393
2394 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2395 {
2396         return single_open(file, sg_proc_seq_show_devhdr, NULL);
2397 }
2398
2399 struct sg_proc_deviter {
2400         loff_t  index;
2401         size_t  max;
2402 };
2403
2404 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2405 {
2406         struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2407
2408         s->private = it;
2409         if (! it)
2410                 return NULL;
2411
2412         it->index = *pos;
2413         it->max = sg_last_dev();
2414         if (it->index >= it->max)
2415                 return NULL;
2416         return it;
2417 }
2418
2419 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2420 {
2421         struct sg_proc_deviter * it = s->private;
2422
2423         *pos = ++it->index;
2424         return (it->index < it->max) ? it : NULL;
2425 }
2426
2427 static void dev_seq_stop(struct seq_file *s, void *v)
2428 {
2429         kfree(s->private);
2430 }
2431
2432 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2433 {
2434         return seq_open(file, &dev_seq_ops);
2435 }
2436
2437 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2438 {
2439         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2440         Sg_device *sdp;
2441         struct scsi_device *scsidp;
2442         unsigned long iflags;
2443
2444         read_lock_irqsave(&sg_index_lock, iflags);
2445         sdp = it ? sg_lookup_dev(it->index) : NULL;
2446         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2447                 seq_printf(s, "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n",
2448                               scsidp->host->host_no, scsidp->channel,
2449                               scsidp->id, scsidp->lun, (int) scsidp->type,
2450                               1,
2451                               (int) scsidp->queue_depth,
2452                               (int) scsidp->device_busy,
2453                               (int) scsi_device_online(scsidp));
2454         else
2455                 seq_printf(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2456         read_unlock_irqrestore(&sg_index_lock, iflags);
2457         return 0;
2458 }
2459
2460 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2461 {
2462         return seq_open(file, &devstrs_seq_ops);
2463 }
2464
2465 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2466 {
2467         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2468         Sg_device *sdp;
2469         struct scsi_device *scsidp;
2470         unsigned long iflags;
2471
2472         read_lock_irqsave(&sg_index_lock, iflags);
2473         sdp = it ? sg_lookup_dev(it->index) : NULL;
2474         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2475                 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2476                            scsidp->vendor, scsidp->model, scsidp->rev);
2477         else
2478                 seq_printf(s, "<no active device>\n");
2479         read_unlock_irqrestore(&sg_index_lock, iflags);
2480         return 0;
2481 }
2482
2483 /* must be called while holding sg_index_lock */
2484 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2485 {
2486         int k, m, new_interface, blen, usg;
2487         Sg_request *srp;
2488         Sg_fd *fp;
2489         const sg_io_hdr_t *hp;
2490         const char * cp;
2491         unsigned int ms;
2492
2493         k = 0;
2494         list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2495                 k++;
2496                 read_lock(&fp->rq_list_lock); /* irqs already disabled */
2497                 seq_printf(s, "   FD(%d): timeout=%dms bufflen=%d "
2498                            "(res)sgat=%d low_dma=%d\n", k,
2499                            jiffies_to_msecs(fp->timeout),
2500                            fp->reserve.bufflen,
2501                            (int) fp->reserve.k_use_sg,
2502                            (int) fp->low_dma);
2503                 seq_printf(s, "   cmd_q=%d f_packid=%d k_orphan=%d closed=%d\n",
2504                            (int) fp->cmd_q, (int) fp->force_packid,
2505                            (int) fp->keep_orphan, (int) fp->closed);
2506                 for (m = 0, srp = fp->headrp;
2507                                 srp != NULL;
2508                                 ++m, srp = srp->nextrp) {
2509                         hp = &srp->header;
2510                         new_interface = (hp->interface_id == '\0') ? 0 : 1;
2511                         if (srp->res_used) {
2512                                 if (new_interface &&
2513                                     (SG_FLAG_MMAP_IO & hp->flags))
2514                                         cp = "     mmap>> ";
2515                                 else
2516                                         cp = "     rb>> ";
2517                         } else {
2518                                 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2519                                         cp = "     dio>> ";
2520                                 else
2521                                         cp = "     ";
2522                         }
2523                         seq_printf(s, cp);
2524                         blen = srp->data.bufflen;
2525                         usg = srp->data.k_use_sg;
2526                         seq_printf(s, srp->done ?
2527                                    ((1 == srp->done) ?  "rcv:" : "fin:")
2528                                    : "act:");
2529                         seq_printf(s, " id=%d blen=%d",
2530                                    srp->header.pack_id, blen);
2531                         if (srp->done)
2532                                 seq_printf(s, " dur=%d", hp->duration);
2533                         else {
2534                                 ms = jiffies_to_msecs(jiffies);
2535                                 seq_printf(s, " t_o/elap=%d/%d",
2536                                         (new_interface ? hp->timeout :
2537                                                   jiffies_to_msecs(fp->timeout)),
2538                                         (ms > hp->duration ? ms - hp->duration : 0));
2539                         }
2540                         seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2541                                    (int) srp->data.cmd_opcode);
2542                 }
2543                 if (0 == m)
2544                         seq_printf(s, "     No requests active\n");
2545                 read_unlock(&fp->rq_list_lock);
2546         }
2547 }
2548
2549 static int sg_proc_open_debug(struct inode *inode, struct file *file)
2550 {
2551         return seq_open(file, &debug_seq_ops);
2552 }
2553
2554 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2555 {
2556         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2557         Sg_device *sdp;
2558         unsigned long iflags;
2559
2560         if (it && (0 == it->index)) {
2561                 seq_printf(s, "max_active_device=%d(origin 1)\n",
2562                            (int)it->max);
2563                 seq_printf(s, " def_reserved_size=%d\n", sg_big_buff);
2564         }
2565
2566         read_lock_irqsave(&sg_index_lock, iflags);
2567         sdp = it ? sg_lookup_dev(it->index) : NULL;
2568         if (sdp && !list_empty(&sdp->sfds)) {
2569                 struct scsi_device *scsidp = sdp->device;
2570
2571                 seq_printf(s, " >>> device=%s ", sdp->disk->disk_name);
2572                 if (sdp->detached)
2573                         seq_printf(s, "detached pending close ");
2574                 else
2575                         seq_printf
2576                             (s, "scsi%d chan=%d id=%d lun=%d   em=%d",
2577                              scsidp->host->host_no,
2578                              scsidp->channel, scsidp->id,
2579                              scsidp->lun,
2580                              scsidp->host->hostt->emulated);
2581                 seq_printf(s, " sg_tablesize=%d excl=%d\n",
2582                            sdp->sg_tablesize, sdp->exclude);
2583                 sg_proc_debug_helper(s, sdp);
2584         }
2585         read_unlock_irqrestore(&sg_index_lock, iflags);
2586         return 0;
2587 }
2588
2589 #endif                          /* CONFIG_SCSI_PROC_FS */
2590
2591 module_init(init_sg);
2592 module_exit(exit_sg);