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/aio.h>
  39 #include <linux/errno.h>
  40 #include <linux/mtio.h>
  41 #include <linux/ioctl.h>
  42 #include <linux/slab.h>
  43 #include <linux/fcntl.h>
  44 #include <linux/init.h>
  45 #include <linux/poll.h>
  46 #include <linux/moduleparam.h>
  47 #include <linux/cdev.h>
  48 #include <linux/idr.h>
  49 #include <linux/seq_file.h>
  50 #include <linux/blkdev.h>
  51 #include <linux/delay.h>
  52 #include <linux/blktrace_api.h>
  53 #include <linux/mutex.h>
  54 #include <linux/ratelimit.h>
  55
  56 #include "scsi.h"
  57 #include <scsi/scsi_dbg.h>
  58 #include <scsi/scsi_host.h>
  59 #include <scsi/scsi_driver.h>
  60 #include <scsi/scsi_ioctl.h>
  61 #include <scsi/sg.h>
  62
  63 #include "scsi_logging.h"
  64
  65 #ifdef CONFIG_SCSI_PROC_FS
  66 #include <linux/proc_fs.h>
  67 static char *sg_version_date = "20061027";
  68
  69 static int sg_proc_init(void);
  70 static void sg_proc_cleanup(void);
  71 #endif
  72
  73 #define SG_ALLOW_DIO_DEF 0
  74
  75 #define SG_MAX_DEVS 32768
  76
  77 /*
  78  * Suppose you want to calculate the formula muldiv(x,m,d)=int(x * m / d)
  79  * Then when using 32 bit integers x * m may overflow during the calculation.
  80  * Replacing muldiv(x) by muldiv(x)=((x % d) * m) / d + int(x / d) * m
  81  * calculates the same, but prevents the overflow when both m and d
  82  * are "small" numbers (like HZ and USER_HZ).
  83  * Of course an overflow is inavoidable if the result of muldiv doesn't fit
  84  * in 32 bits.
  85  */
  86 #define MULDIV(X,MUL,DIV) ((((X % DIV) * MUL) / DIV) + ((X / DIV) * MUL))
  87
  88 #define SG_DEFAULT_TIMEOUT MULDIV(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
  89
  90 int sg_big_buff = SG_DEF_RESERVED_SIZE;
  91 /* N.B. This variable is readable and writeable via
  92    /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
  93    of this size (or less if there is not enough memory) will be reserved
  94    for use by this file descriptor. [Deprecated usage: this variable is also
  95    readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
  96    the kernel (i.e. it is not a module).] */
  97 static int def_reserved_size = -1;      /* picks up init parameter */
  98 static int sg_allow_dio = SG_ALLOW_DIO_DEF;
  99
 100 static int scatter_elem_sz = SG_SCATTER_SZ;
 101 static int scatter_elem_sz_prev = SG_SCATTER_SZ;
 102
 103 #define SG_SECTOR_SZ 512
 104
 105 static int sg_add(struct device *, struct class_interface *);
 106 static void sg_remove(struct device *, struct class_interface *);
 107
 108 static DEFINE_IDR(sg_index_idr);
 109 static DEFINE_RWLOCK(sg_index_lock);
 110
 111 static struct class_interface sg_interface = {
 112         .add_dev        = sg_add,
 113         .remove_dev     = sg_remove,
 114 };
 115
 116 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
 117         unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
 118         unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */
 119         unsigned bufflen;       /* Size of (aggregate) data buffer */
 120         struct page **pages;
 121         int page_order;
 122         char dio_in_use;        /* 0->indirect IO (or mmap), 1->dio */
 123         unsigned char cmd_opcode; /* first byte of command */
 124 } Sg_scatter_hold;
 125
 126 struct sg_device;               /* forward declarations */
 127 struct sg_fd;
 128
 129 typedef struct sg_request {     /* SG_MAX_QUEUE requests outstanding per file */
 130         struct sg_request *nextrp;      /* NULL -> tail request (slist) */
 131         struct sg_fd *parentfp; /* NULL -> not in use */
 132         Sg_scatter_hold data;   /* hold buffer, perhaps scatter list */
 133         sg_io_hdr_t header;     /* scsi command+info, see <scsi/sg.h> */
 134         unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
 135         char res_used;          /* 1 -> using reserve buffer, 0 -> not ... */
 136         char orphan;            /* 1 -> drop on sight, 0 -> normal */
 137         char sg_io_owned;       /* 1 -> packet belongs to SG_IO */
 138         /* done protected by rq_list_lock */
 139         char done;              /* 0->before bh, 1->before read, 2->read */
 140         struct request *rq;
 141         struct bio *bio;
 142         struct execute_work ew;
 143 } Sg_request;
 144
 145 typedef struct sg_fd {          /* holds the state of a file descriptor */
 146         struct list_head sfd_siblings; /* protected by sfd_lock of device */
 147         struct sg_device *parentdp;     /* owning device */
 148         wait_queue_head_t read_wait;    /* queue read until command done */
 149         rwlock_t rq_list_lock;  /* protect access to list in req_arr */
 150         int timeout;            /* defaults to SG_DEFAULT_TIMEOUT      */
 151         int timeout_user;       /* defaults to SG_DEFAULT_TIMEOUT_USER */
 152         Sg_scatter_hold reserve;        /* buffer held for this file descriptor */
 153         unsigned save_scat_len; /* original length of trunc. scat. element */
 154         Sg_request *headrp;     /* head of request slist, NULL->empty */
 155         struct fasync_struct *async_qp; /* used by asynchronous notification */
 156         Sg_request req_arr[SG_MAX_QUEUE];       /* used as singly-linked list */
 157         char low_dma;           /* as in parent but possibly overridden to 1 */
 158         char force_packid;      /* 1 -> pack_id input to read(), 0 -> ignored */
 159         char cmd_q;             /* 1 -> allow command queuing, 0 -> don't */
 160         char next_cmd_len;      /* 0 -> automatic (def), >0 -> use on next write() */
 161         char keep_orphan;       /* 0 -> drop orphan (def), 1 -> keep for read() */
 162         char mmap_called;       /* 0 -> mmap() never called on this fd */
 163         struct kref f_ref;
 164         struct execute_work ew;
 165 } Sg_fd;
 166
 167 typedef struct sg_device { /* holds the state of each scsi generic device */
 168         struct scsi_device *device;
 169         int sg_tablesize;       /* adapter's max scatter-gather table size */
 170         u32 index;              /* device index number */
 171         spinlock_t sfd_lock;    /* protect file descriptor list for device */
 172         struct list_head sfds;
 173         struct rw_semaphore o_sem;      /* exclude open should hold this rwsem */
 174         volatile char detached; /* 0->attached, 1->detached pending removal */
 175         char exclude;           /* opened for exclusive access */
 176         char sgdebug;           /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
 177         struct gendisk *disk;
 178         struct cdev * cdev;     /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
 179         struct kref d_ref;
 180 } Sg_device;
 181
 182 /* tasklet or soft irq callback */
 183 static void sg_rq_end_io(struct request *rq, int uptodate);
 184 static int sg_start_req(Sg_request *srp, unsigned char *cmd);
 185 static int sg_finish_rem_req(Sg_request * srp);
 186 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
 187 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
 188                            Sg_request * srp);
 189 static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
 190                         const char __user *buf, size_t count, int blocking,
 191                         int read_only, int sg_io_owned, Sg_request **o_srp);
 192 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
 193                            unsigned char *cmnd, int timeout, int blocking);
 194 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
 195 static void sg_remove_scat(Sg_scatter_hold * schp);
 196 static void sg_build_reserve(Sg_fd * sfp, int req_size);
 197 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
 198 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
 199 static Sg_fd *sg_add_sfp(Sg_device * sdp, int dev);
 200 static void sg_remove_sfp(struct kref *);
 201 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
 202 static Sg_request *sg_add_request(Sg_fd * sfp);
 203 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
 204 static int sg_res_in_use(Sg_fd * sfp);
 205 static Sg_device *sg_get_dev(int dev);
 206 static void sg_put_dev(Sg_device *sdp);
 207
 208 #define SZ_SG_HEADER sizeof(struct sg_header)
 209 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
 210 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
 211 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
 212
 213 static int sg_allow_access(struct file *filp, unsigned char *cmd)
 214 {
 215         struct sg_fd *sfp = filp->private_data;
 216
 217         if (sfp->parentdp->device->type == TYPE_SCANNER)
 218                 return 0;
 219
 220         return blk_verify_command(cmd, filp->f_mode & FMODE_WRITE);
 221 }
 222
 223 static int sfds_list_empty(Sg_device *sdp)
 224 {
 225         unsigned long flags;
 226         int ret;
 227
 228         spin_lock_irqsave(&sdp->sfd_lock, flags);
 229         ret = list_empty(&sdp->sfds);
 230         spin_unlock_irqrestore(&sdp->sfd_lock, flags);
 231         return ret;
 232 }
 233
 234 static int
 235 sg_open(struct inode *inode, struct file *filp)
 236 {
 237         int dev = iminor(inode);
 238         int flags = filp->f_flags;
 239         struct request_queue *q;
 240         Sg_device *sdp;
 241         Sg_fd *sfp;
 242         int retval;
 243
 244         nonseekable_open(inode, filp);
 245         SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags));
 246         sdp = sg_get_dev(dev);
 247         if (IS_ERR(sdp)) {
 248                 retval = PTR_ERR(sdp);
 249                 sdp = NULL;
 250                 goto sg_put;
 251         }
 252
 253         /* This driver's module count bumped by fops_get in <linux/fs.h> */
 254         /* Prevent the device driver from vanishing while we sleep */
 255         retval = scsi_device_get(sdp->device);
 256         if (retval)
 257                 goto sg_put;
 258
 259         retval = scsi_autopm_get_device(sdp->device);
 260         if (retval)
 261                 goto sdp_put;
 262
 263         if (!((flags & O_NONBLOCK) ||
 264               scsi_block_when_processing_errors(sdp->device))) {
 265                 retval = -ENXIO;
 266                 /* we are in error recovery for this device */
 267                 goto error_out;
 268         }
 269
 270         if ((flags & O_EXCL) && (O_RDONLY == (flags & O_ACCMODE))) {
 271                 retval = -EPERM; /* Can't lock it with read only access */
 272                 goto error_out;
 273         }
 274         if (flags & O_NONBLOCK) {
 275                 if (flags & O_EXCL) {
 276                         if (!down_write_trylock(&sdp->o_sem)) {
 277                                 retval = -EBUSY;
 278                                 goto error_out;
 279                         }
 280                 } else {
 281                         if (!down_read_trylock(&sdp->o_sem)) {
 282                                 retval = -EBUSY;
 283                                 goto error_out;
 284                         }
 285                 }
 286         } else {
 287                 if (flags & O_EXCL)
 288                         down_write(&sdp->o_sem);
 289                 else
 290                         down_read(&sdp->o_sem);
 291         }
 292         /* Since write lock is held, no need to check sfd_list */
 293         if (flags & O_EXCL)
 294                 sdp->exclude = 1;       /* used by release lock */
 295
 296         if (sfds_list_empty(sdp)) {     /* no existing opens on this device */
 297                 sdp->sgdebug = 0;
 298                 q = sdp->device->request_queue;
 299                 sdp->sg_tablesize = queue_max_segments(q);
 300         }
 301         sfp = sg_add_sfp(sdp, dev);
 302         if (!IS_ERR(sfp))
 303                 filp->private_data = sfp;
 304                 /* retval is already provably zero at this point because of the
 305                  * check after retval = scsi_autopm_get_device(sdp->device))
 306                  */
 307         else {
 308                 retval = PTR_ERR(sfp);
 309
 310                 if (flags & O_EXCL) {
 311                         sdp->exclude = 0;       /* undo if error */
 312                         up_write(&sdp->o_sem);
 313                 } else
 314                         up_read(&sdp->o_sem);
 315 error_out:
 316                 scsi_autopm_put_device(sdp->device);
 317 sdp_put:
 318                 scsi_device_put(sdp->device);
 319         }
 320 sg_put:
 321         if (sdp)
 322                 sg_put_dev(sdp);
 323         return retval;
 324 }
 325
 326 /* Following function was formerly called 'sg_close' */
 327 static int
 328 sg_release(struct inode *inode, struct file *filp)
 329 {
 330         Sg_device *sdp;
 331         Sg_fd *sfp;
 332         int excl;
 333
 334         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 335                 return -ENXIO;
 336         SCSI_LOG_TIMEOUT(3, printk("sg_release: %s\n", sdp->disk->disk_name));
 337
 338         excl = sdp->exclude;
 339         sdp->exclude = 0;
 340         if (excl)
 341                 up_write(&sdp->o_sem);
 342         else
 343                 up_read(&sdp->o_sem);
 344
 345         scsi_autopm_put_device(sdp->device);
 346         kref_put(&sfp->f_ref, sg_remove_sfp);
 347         return 0;
 348 }
 349
 350 static ssize_t
 351 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
 352 {
 353         Sg_device *sdp;
 354         Sg_fd *sfp;
 355         Sg_request *srp;
 356         int req_pack_id = -1;
 357         sg_io_hdr_t *hp;
 358         struct sg_header *old_hdr = NULL;
 359         int retval = 0;
 360
 361         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 362                 return -ENXIO;
 363         SCSI_LOG_TIMEOUT(3, printk("sg_read: %s, count=%d\n",
 364                                    sdp->disk->disk_name, (int) count));
 365
 366         if (!access_ok(VERIFY_WRITE, buf, count))
 367                 return -EFAULT;
 368         if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
 369                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 370                 if (!old_hdr)
 371                         return -ENOMEM;
 372                 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
 373                         retval = -EFAULT;
 374                         goto free_old_hdr;
 375                 }
 376                 if (old_hdr->reply_len < 0) {
 377                         if (count >= SZ_SG_IO_HDR) {
 378                                 sg_io_hdr_t *new_hdr;
 379                                 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
 380                                 if (!new_hdr) {
 381                                         retval = -ENOMEM;
 382                                         goto free_old_hdr;
 383                                 }
 384                                 retval =__copy_from_user
 385                                     (new_hdr, buf, SZ_SG_IO_HDR);
 386                                 req_pack_id = new_hdr->pack_id;
 387                                 kfree(new_hdr);
 388                                 if (retval) {
 389                                         retval = -EFAULT;
 390                                         goto free_old_hdr;
 391                                 }
 392                         }
 393                 } else
 394                         req_pack_id = old_hdr->pack_id;
 395         }
 396         srp = sg_get_rq_mark(sfp, req_pack_id);
 397         if (!srp) {             /* now wait on packet to arrive */
 398                 if (sdp->detached) {
 399                         retval = -ENODEV;
 400                         goto free_old_hdr;
 401                 }
 402                 if (filp->f_flags & O_NONBLOCK) {
 403                         retval = -EAGAIN;
 404                         goto free_old_hdr;
 405                 }
 406                 retval = wait_event_interruptible(sfp->read_wait,
 407                         (sdp->detached ||
 408                         (srp = sg_get_rq_mark(sfp, req_pack_id))));
 409                 if (sdp->detached) {
 410                         retval = -ENODEV;
 411                         goto free_old_hdr;
 412                 }
 413                 if (retval) {
 414                         /* -ERESTARTSYS as signal hit process */
 415                         goto free_old_hdr;
 416                 }
 417         }
 418         if (srp->header.interface_id != '\0') {
 419                 retval = sg_new_read(sfp, buf, count, srp);
 420                 goto free_old_hdr;
 421         }
 422
 423         hp = &srp->header;
 424         if (old_hdr == NULL) {
 425                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 426                 if (! old_hdr) {
 427                         retval = -ENOMEM;
 428                         goto free_old_hdr;
 429                 }
 430         }
 431         memset(old_hdr, 0, SZ_SG_HEADER);
 432         old_hdr->reply_len = (int) hp->timeout;
 433         old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
 434         old_hdr->pack_id = hp->pack_id;
 435         old_hdr->twelve_byte =
 436             ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
 437         old_hdr->target_status = hp->masked_status;
 438         old_hdr->host_status = hp->host_status;
 439         old_hdr->driver_status = hp->driver_status;
 440         if ((CHECK_CONDITION & hp->masked_status) ||
 441             (DRIVER_SENSE & hp->driver_status))
 442                 memcpy(old_hdr->sense_buffer, srp->sense_b,
 443                        sizeof (old_hdr->sense_buffer));
 444         switch (hp->host_status) {
 445         /* This setup of 'result' is for backward compatibility and is best
 446            ignored by the user who should use target, host + driver status */
 447         case DID_OK:
 448         case DID_PASSTHROUGH:
 449         case DID_SOFT_ERROR:
 450                 old_hdr->result = 0;
 451                 break;
 452         case DID_NO_CONNECT:
 453         case DID_BUS_BUSY:
 454         case DID_TIME_OUT:
 455                 old_hdr->result = EBUSY;
 456                 break;
 457         case DID_BAD_TARGET:
 458         case DID_ABORT:
 459         case DID_PARITY:
 460         case DID_RESET:
 461         case DID_BAD_INTR:
 462                 old_hdr->result = EIO;
 463                 break;
 464         case DID_ERROR:
 465                 old_hdr->result = (srp->sense_b[0] == 0 &&
 466                                   hp->masked_status == GOOD) ? 0 : EIO;
 467                 break;
 468         default:
 469                 old_hdr->result = EIO;
 470                 break;
 471         }
 472
 473         /* Now copy the result back to the user buffer.  */
 474         if (count >= SZ_SG_HEADER) {
 475                 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
 476                         retval = -EFAULT;
 477                         goto free_old_hdr;
 478                 }
 479                 buf += SZ_SG_HEADER;
 480                 if (count > old_hdr->reply_len)
 481                         count = old_hdr->reply_len;
 482                 if (count > SZ_SG_HEADER) {
 483                         if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
 484                                 retval = -EFAULT;
 485                                 goto free_old_hdr;
 486                         }
 487                 }
 488         } else
 489                 count = (old_hdr->result == 0) ? 0 : -EIO;
 490         sg_finish_rem_req(srp);
 491         retval = count;
 492 free_old_hdr:
 493         kfree(old_hdr);
 494         return retval;
 495 }
 496
 497 static ssize_t
 498 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
 499 {
 500         sg_io_hdr_t *hp = &srp->header;
 501         int err = 0;
 502         int len;
 503
 504         if (count < SZ_SG_IO_HDR) {
 505                 err = -EINVAL;
 506                 goto err_out;
 507         }
 508         hp->sb_len_wr = 0;
 509         if ((hp->mx_sb_len > 0) && hp->sbp) {
 510                 if ((CHECK_CONDITION & hp->masked_status) ||
 511                     (DRIVER_SENSE & hp->driver_status)) {
 512                         int sb_len = SCSI_SENSE_BUFFERSIZE;
 513                         sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
 514                         len = 8 + (int) srp->sense_b[7];        /* Additional sense length field */
 515                         len = (len > sb_len) ? sb_len : len;
 516                         if (copy_to_user(hp->sbp, srp->sense_b, len)) {
 517                                 err = -EFAULT;
 518                                 goto err_out;
 519                         }
 520                         hp->sb_len_wr = len;
 521                 }
 522         }
 523         if (hp->masked_status || hp->host_status || hp->driver_status)
 524                 hp->info |= SG_INFO_CHECK;
 525         if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
 526                 err = -EFAULT;
 527                 goto err_out;
 528         }
 529 err_out:
 530         err = sg_finish_rem_req(srp);
 531         return (0 == err) ? count : err;
 532 }
 533
 534 static ssize_t
 535 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
 536 {
 537         int mxsize, cmd_size, k;
 538         int input_size, blocking;
 539         unsigned char opcode;
 540         Sg_device *sdp;
 541         Sg_fd *sfp;
 542         Sg_request *srp;
 543         struct sg_header old_hdr;
 544         sg_io_hdr_t *hp;
 545         unsigned char cmnd[MAX_COMMAND_SIZE];
 546
 547         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 548                 return -ENXIO;
 549         SCSI_LOG_TIMEOUT(3, printk("sg_write: %s, count=%d\n",
 550                                    sdp->disk->disk_name, (int) count));
 551         if (sdp->detached)
 552                 return -ENODEV;
 553         if (!((filp->f_flags & O_NONBLOCK) ||
 554               scsi_block_when_processing_errors(sdp->device)))
 555                 return -ENXIO;
 556
 557         if (!access_ok(VERIFY_READ, buf, count))
 558                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 559         if (count < SZ_SG_HEADER)
 560                 return -EIO;
 561         if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
 562                 return -EFAULT;
 563         blocking = !(filp->f_flags & O_NONBLOCK);
 564         if (old_hdr.reply_len < 0)
 565                 return sg_new_write(sfp, filp, buf, count,
 566                                     blocking, 0, 0, NULL);
 567         if (count < (SZ_SG_HEADER + 6))
 568                 return -EIO;    /* The minimum scsi command length is 6 bytes. */
 569
 570         if (!(srp = sg_add_request(sfp))) {
 571                 SCSI_LOG_TIMEOUT(1, printk("sg_write: queue full\n"));
 572                 return -EDOM;
 573         }
 574         buf += SZ_SG_HEADER;
 575         __get_user(opcode, buf);
 576         if (sfp->next_cmd_len > 0) {
 577                 if (sfp->next_cmd_len > MAX_COMMAND_SIZE) {
 578                         SCSI_LOG_TIMEOUT(1, printk("sg_write: command length too long\n"));
 579                         sfp->next_cmd_len = 0;
 580                         sg_remove_request(sfp, srp);
 581                         return -EIO;
 582                 }
 583                 cmd_size = sfp->next_cmd_len;
 584                 sfp->next_cmd_len = 0;  /* reset so only this write() effected */
 585         } else {
 586                 cmd_size = COMMAND_SIZE(opcode);        /* based on SCSI command group */
 587                 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
 588                         cmd_size = 12;
 589         }
 590         SCSI_LOG_TIMEOUT(4, printk(
 591                 "sg_write:   scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
 592 /* Determine buffer size.  */
 593         input_size = count - cmd_size;
 594         mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
 595         mxsize -= SZ_SG_HEADER;
 596         input_size -= SZ_SG_HEADER;
 597         if (input_size < 0) {
 598                 sg_remove_request(sfp, srp);
 599                 return -EIO;    /* User did not pass enough bytes for this command. */
 600         }
 601         hp = &srp->header;
 602         hp->interface_id = '\0';        /* indicator of old interface tunnelled */
 603         hp->cmd_len = (unsigned char) cmd_size;
 604         hp->iovec_count = 0;
 605         hp->mx_sb_len = 0;
 606         if (input_size > 0)
 607                 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
 608                     SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
 609         else
 610                 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
 611         hp->dxfer_len = mxsize;
 612         if (hp->dxfer_direction == SG_DXFER_TO_DEV)
 613                 hp->dxferp = (char __user *)buf + cmd_size;
 614         else
 615                 hp->dxferp = NULL;
 616         hp->sbp = NULL;
 617         hp->timeout = old_hdr.reply_len;        /* structure abuse ... */
 618         hp->flags = input_size; /* structure abuse ... */
 619         hp->pack_id = old_hdr.pack_id;
 620         hp->usr_ptr = NULL;
 621         if (__copy_from_user(cmnd, buf, cmd_size))
 622                 return -EFAULT;
 623         /*
 624          * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
 625          * but is is possible that the app intended SG_DXFER_TO_DEV, because there
 626          * is a non-zero input_size, so emit a warning.
 627          */
 628         if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
 629                 static char cmd[TASK_COMM_LEN];
 630                 if (strcmp(current->comm, cmd)) {
 631                         printk_ratelimited(KERN_WARNING
 632                                            "sg_write: data in/out %d/%d bytes "
 633                                            "for SCSI command 0x%x-- guessing "
 634                                            "data in;\n   program %s not setting "
 635                                            "count and/or reply_len properly\n",
 636                                            old_hdr.reply_len - (int)SZ_SG_HEADER,
 637                                            input_size, (unsigned int) cmnd[0],
 638                                            current->comm);
 639                         strcpy(cmd, current->comm);
 640                 }
 641         }
 642         k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
 643         return (k < 0) ? k : count;
 644 }
 645
 646 static ssize_t
 647 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
 648                  size_t count, int blocking, int read_only, int sg_io_owned,
 649                  Sg_request **o_srp)
 650 {
 651         int k;
 652         Sg_request *srp;
 653         sg_io_hdr_t *hp;
 654         unsigned char cmnd[MAX_COMMAND_SIZE];
 655         int timeout;
 656         unsigned long ul_timeout;
 657
 658         if (count < SZ_SG_IO_HDR)
 659                 return -EINVAL;
 660         if (!access_ok(VERIFY_READ, buf, count))
 661                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 662
 663         sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
 664         if (!(srp = sg_add_request(sfp))) {
 665                 SCSI_LOG_TIMEOUT(1, printk("sg_new_write: queue full\n"));
 666                 return -EDOM;
 667         }
 668         srp->sg_io_owned = sg_io_owned;
 669         hp = &srp->header;
 670         if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
 671                 sg_remove_request(sfp, srp);
 672                 return -EFAULT;
 673         }
 674         if (hp->interface_id != 'S') {
 675                 sg_remove_request(sfp, srp);
 676                 return -ENOSYS;
 677         }
 678         if (hp->flags & SG_FLAG_MMAP_IO) {
 679                 if (hp->dxfer_len > sfp->reserve.bufflen) {
 680                         sg_remove_request(sfp, srp);
 681                         return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
 682                 }
 683                 if (hp->flags & SG_FLAG_DIRECT_IO) {
 684                         sg_remove_request(sfp, srp);
 685                         return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
 686                 }
 687                 if (sg_res_in_use(sfp)) {
 688                         sg_remove_request(sfp, srp);
 689                         return -EBUSY;  /* reserve buffer already being used */
 690                 }
 691         }
 692         ul_timeout = msecs_to_jiffies(srp->header.timeout);
 693         timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
 694         if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
 695                 sg_remove_request(sfp, srp);
 696                 return -EMSGSIZE;
 697         }
 698         if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
 699                 sg_remove_request(sfp, srp);
 700                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 701         }
 702         if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
 703                 sg_remove_request(sfp, srp);
 704                 return -EFAULT;
 705         }
 706         if (read_only && sg_allow_access(file, cmnd)) {
 707                 sg_remove_request(sfp, srp);
 708                 return -EPERM;
 709         }
 710         k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
 711         if (k < 0)
 712                 return k;
 713         if (o_srp)
 714                 *o_srp = srp;
 715         return count;
 716 }
 717
 718 static int
 719 sg_common_write(Sg_fd * sfp, Sg_request * srp,
 720                 unsigned char *cmnd, int timeout, int blocking)
 721 {
 722         int k, data_dir;
 723         Sg_device *sdp = sfp->parentdp;
 724         sg_io_hdr_t *hp = &srp->header;
 725
 726         srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
 727         hp->status = 0;
 728         hp->masked_status = 0;
 729         hp->msg_status = 0;
 730         hp->info = 0;
 731         hp->host_status = 0;
 732         hp->driver_status = 0;
 733         hp->resid = 0;
 734         SCSI_LOG_TIMEOUT(4, printk("sg_common_write:  scsi opcode=0x%02x, cmd_size=%d\n",
 735                           (int) cmnd[0], (int) hp->cmd_len));
 736
 737         k = sg_start_req(srp, cmnd);
 738         if (k) {
 739                 SCSI_LOG_TIMEOUT(1, printk("sg_common_write: start_req err=%d\n", k));
 740                 sg_finish_rem_req(srp);
 741                 return k;       /* probably out of space --> ENOMEM */
 742         }
 743         if (sdp->detached) {
 744                 if (srp->bio)
 745                         blk_end_request_all(srp->rq, -EIO);
 746                 sg_finish_rem_req(srp);
 747                 return -ENODEV;
 748         }
 749
 750         switch (hp->dxfer_direction) {
 751         case SG_DXFER_TO_FROM_DEV:
 752         case SG_DXFER_FROM_DEV:
 753                 data_dir = DMA_FROM_DEVICE;
 754                 break;
 755         case SG_DXFER_TO_DEV:
 756                 data_dir = DMA_TO_DEVICE;
 757                 break;
 758         case SG_DXFER_UNKNOWN:
 759                 data_dir = DMA_BIDIRECTIONAL;
 760                 break;
 761         default:
 762                 data_dir = DMA_NONE;
 763                 break;
 764         }
 765         hp->duration = jiffies_to_msecs(jiffies);
 766
 767         srp->rq->timeout = timeout;
 768         kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
 769         blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk,
 770                               srp->rq, 1, sg_rq_end_io);
 771         return 0;
 772 }
 773
 774 static int srp_done(Sg_fd *sfp, Sg_request *srp)
 775 {
 776         unsigned long flags;
 777         int ret;
 778
 779         read_lock_irqsave(&sfp->rq_list_lock, flags);
 780         ret = srp->done;
 781         read_unlock_irqrestore(&sfp->rq_list_lock, flags);
 782         return ret;
 783 }
 784
 785 static long
 786 sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
 787 {
 788         void __user *p = (void __user *)arg;
 789         int __user *ip = p;
 790         int result, val, read_only;
 791         Sg_device *sdp;
 792         Sg_fd *sfp;
 793         Sg_request *srp;
 794         unsigned long iflags;
 795
 796         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 797                 return -ENXIO;
 798
 799         SCSI_LOG_TIMEOUT(3, printk("sg_ioctl: %s, cmd=0x%x\n",
 800                                    sdp->disk->disk_name, (int) cmd_in));
 801         read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
 802
 803         switch (cmd_in) {
 804         case SG_IO:
 805                 if (sdp->detached)
 806                         return -ENODEV;
 807                 if (!scsi_block_when_processing_errors(sdp->device))
 808                         return -ENXIO;
 809                 if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
 810                         return -EFAULT;
 811                 result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
 812                                  1, read_only, 1, &srp);
 813                 if (result < 0)
 814                         return result;
 815                 result = wait_event_interruptible(sfp->read_wait,
 816                         (srp_done(sfp, srp) || sdp->detached));
 817                 if (sdp->detached)
 818                         return -ENODEV;
 819                 write_lock_irq(&sfp->rq_list_lock);
 820                 if (srp->done) {
 821                         srp->done = 2;
 822                         write_unlock_irq(&sfp->rq_list_lock);
 823                         result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
 824                         return (result < 0) ? result : 0;
 825                 }
 826                 srp->orphan = 1;
 827                 write_unlock_irq(&sfp->rq_list_lock);
 828                 return result;  /* -ERESTARTSYS because signal hit process */
 829         case SG_SET_TIMEOUT:
 830                 result = get_user(val, ip);
 831                 if (result)
 832                         return result;
 833                 if (val < 0)
 834                         return -EIO;
 835                 if (val >= MULDIV (INT_MAX, USER_HZ, HZ))
 836                     val = MULDIV (INT_MAX, USER_HZ, HZ);
 837                 sfp->timeout_user = val;
 838                 sfp->timeout = MULDIV (val, HZ, USER_HZ);
 839
 840                 return 0;
 841         case SG_GET_TIMEOUT:    /* N.B. User receives timeout as return value */
 842                                 /* strange ..., for backward compatibility */
 843                 return sfp->timeout_user;
 844         case SG_SET_FORCE_LOW_DMA:
 845                 result = get_user(val, ip);
 846                 if (result)
 847                         return result;
 848                 if (val) {
 849                         sfp->low_dma = 1;
 850                         if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
 851                                 val = (int) sfp->reserve.bufflen;
 852                                 sg_remove_scat(&sfp->reserve);
 853                                 sg_build_reserve(sfp, val);
 854                         }
 855                 } else {
 856                         if (sdp->detached)
 857                                 return -ENODEV;
 858                         sfp->low_dma = sdp->device->host->unchecked_isa_dma;
 859                 }
 860                 return 0;
 861         case SG_GET_LOW_DMA:
 862                 return put_user((int) sfp->low_dma, ip);
 863         case SG_GET_SCSI_ID:
 864                 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
 865                         return -EFAULT;
 866                 else {
 867                         sg_scsi_id_t __user *sg_idp = p;
 868
 869                         if (sdp->detached)
 870                                 return -ENODEV;
 871                         __put_user((int) sdp->device->host->host_no,
 872                                    &sg_idp->host_no);
 873                         __put_user((int) sdp->device->channel,
 874                                    &sg_idp->channel);
 875                         __put_user((int) sdp->device->id, &sg_idp->scsi_id);
 876                         __put_user((int) sdp->device->lun, &sg_idp->lun);
 877                         __put_user((int) sdp->device->type, &sg_idp->scsi_type);
 878                         __put_user((short) sdp->device->host->cmd_per_lun,
 879                                    &sg_idp->h_cmd_per_lun);
 880                         __put_user((short) sdp->device->queue_depth,
 881                                    &sg_idp->d_queue_depth);
 882                         __put_user(0, &sg_idp->unused[0]);
 883                         __put_user(0, &sg_idp->unused[1]);
 884                         return 0;
 885                 }
 886         case SG_SET_FORCE_PACK_ID:
 887                 result = get_user(val, ip);
 888                 if (result)
 889                         return result;
 890                 sfp->force_packid = val ? 1 : 0;
 891                 return 0;
 892         case SG_GET_PACK_ID:
 893                 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
 894                         return -EFAULT;
 895                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 896                 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
 897                         if ((1 == srp->done) && (!srp->sg_io_owned)) {
 898                                 read_unlock_irqrestore(&sfp->rq_list_lock,
 899                                                        iflags);
 900                                 __put_user(srp->header.pack_id, ip);
 901                                 return 0;
 902                         }
 903                 }
 904                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 905                 __put_user(-1, ip);
 906                 return 0;
 907         case SG_GET_NUM_WAITING:
 908                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 909                 for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) {
 910                         if ((1 == srp->done) && (!srp->sg_io_owned))
 911                                 ++val;
 912                 }
 913                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 914                 return put_user(val, ip);
 915         case SG_GET_SG_TABLESIZE:
 916                 return put_user(sdp->sg_tablesize, ip);
 917         case SG_SET_RESERVED_SIZE:
 918                 result = get_user(val, ip);
 919                 if (result)
 920                         return result;
 921                 if (val < 0)
 922                         return -EINVAL;
 923                 val = min_t(int, val,
 924                             queue_max_sectors(sdp->device->request_queue) * 512);
 925                 if (val != sfp->reserve.bufflen) {
 926                         if (sg_res_in_use(sfp) || sfp->mmap_called)
 927                                 return -EBUSY;
 928                         sg_remove_scat(&sfp->reserve);
 929                         sg_build_reserve(sfp, val);
 930                 }
 931                 return 0;
 932         case SG_GET_RESERVED_SIZE:
 933                 val = min_t(int, sfp->reserve.bufflen,
 934                             queue_max_sectors(sdp->device->request_queue) * 512);
 935                 return put_user(val, ip);
 936         case SG_SET_COMMAND_Q:
 937                 result = get_user(val, ip);
 938                 if (result)
 939                         return result;
 940                 sfp->cmd_q = val ? 1 : 0;
 941                 return 0;
 942         case SG_GET_COMMAND_Q:
 943                 return put_user((int) sfp->cmd_q, ip);
 944         case SG_SET_KEEP_ORPHAN:
 945                 result = get_user(val, ip);
 946                 if (result)
 947                         return result;
 948                 sfp->keep_orphan = val;
 949                 return 0;
 950         case SG_GET_KEEP_ORPHAN:
 951                 return put_user((int) sfp->keep_orphan, ip);
 952         case SG_NEXT_CMD_LEN:
 953                 result = get_user(val, ip);
 954                 if (result)
 955                         return result;
 956                 sfp->next_cmd_len = (val > 0) ? val : 0;
 957                 return 0;
 958         case SG_GET_VERSION_NUM:
 959                 return put_user(sg_version_num, ip);
 960         case SG_GET_ACCESS_COUNT:
 961                 /* faked - we don't have a real access count anymore */
 962                 val = (sdp->device ? 1 : 0);
 963                 return put_user(val, ip);
 964         case SG_GET_REQUEST_TABLE:
 965                 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
 966                         return -EFAULT;
 967                 else {
 968                         sg_req_info_t *rinfo;
 969                         unsigned int ms;
 970
 971                         rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
 972                                                                 GFP_KERNEL);
 973                         if (!rinfo)
 974                                 return -ENOMEM;
 975                         read_lock_irqsave(&sfp->rq_list_lock, iflags);
 976                         for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE;
 977                              ++val, srp = srp ? srp->nextrp : srp) {
 978                                 memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
 979                                 if (srp) {
 980                                         rinfo[val].req_state = srp->done + 1;
 981                                         rinfo[val].problem =
 982                                             srp->header.masked_status &
 983                                             srp->header.host_status &
 984                                             srp->header.driver_status;
 985                                         if (srp->done)
 986                                                 rinfo[val].duration =
 987                                                         srp->header.duration;
 988                                         else {
 989                                                 ms = jiffies_to_msecs(jiffies);
 990                                                 rinfo[val].duration =
 991                                                     (ms > srp->header.duration) ?
 992                                                     (ms - srp->header.duration) : 0;
 993                                         }
 994                                         rinfo[val].orphan = srp->orphan;
 995                                         rinfo[val].sg_io_owned =
 996                                                         srp->sg_io_owned;
 997                                         rinfo[val].pack_id =
 998                                                         srp->header.pack_id;
 999                                         rinfo[val].usr_ptr =
1000                                                         srp->header.usr_ptr;
1001                                 }
1002                         }
1003                         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1004                         result = __copy_to_user(p, rinfo,
1005                                                 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1006                         result = result ? -EFAULT : 0;
1007                         kfree(rinfo);
1008                         return result;
1009                 }
1010         case SG_EMULATED_HOST:
1011                 if (sdp->detached)
1012                         return -ENODEV;
1013                 return put_user(sdp->device->host->hostt->emulated, ip);
1014         case SG_SCSI_RESET:
1015                 if (sdp->detached)
1016                         return -ENODEV;
1017                 if (filp->f_flags & O_NONBLOCK) {
1018                         if (scsi_host_in_recovery(sdp->device->host))
1019                                 return -EBUSY;
1020                 } else if (!scsi_block_when_processing_errors(sdp->device))
1021                         return -EBUSY;
1022                 result = get_user(val, ip);
1023                 if (result)
1024                         return result;
1025                 if (SG_SCSI_RESET_NOTHING == val)
1026                         return 0;
1027                 switch (val) {
1028                 case SG_SCSI_RESET_DEVICE:
1029                         val = SCSI_TRY_RESET_DEVICE;
1030                         break;
1031                 case SG_SCSI_RESET_TARGET:
1032                         val = SCSI_TRY_RESET_TARGET;
1033                         break;
1034                 case SG_SCSI_RESET_BUS:
1035                         val = SCSI_TRY_RESET_BUS;
1036                         break;
1037                 case SG_SCSI_RESET_HOST:
1038                         val = SCSI_TRY_RESET_HOST;
1039                         break;
1040                 default:
1041                         return -EINVAL;
1042                 }
1043                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1044                         return -EACCES;
1045                 return (scsi_reset_provider(sdp->device, val) ==
1046                         SUCCESS) ? 0 : -EIO;
1047         case SCSI_IOCTL_SEND_COMMAND:
1048                 if (sdp->detached)
1049                         return -ENODEV;
1050                 if (read_only) {
1051                         unsigned char opcode = WRITE_6;
1052                         Scsi_Ioctl_Command __user *siocp = p;
1053
1054                         if (copy_from_user(&opcode, siocp->data, 1))
1055                                 return -EFAULT;
1056                         if (sg_allow_access(filp, &opcode))
1057                                 return -EPERM;
1058                 }
1059                 return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p);
1060         case SG_SET_DEBUG:
1061                 result = get_user(val, ip);
1062                 if (result)
1063                         return result;
1064                 sdp->sgdebug = (char) val;
1065                 return 0;
1066         case SCSI_IOCTL_GET_IDLUN:
1067         case SCSI_IOCTL_GET_BUS_NUMBER:
1068         case SCSI_IOCTL_PROBE_HOST:
1069         case SG_GET_TRANSFORM:
1070                 if (sdp->detached)
1071                         return -ENODEV;
1072                 return scsi_ioctl(sdp->device, cmd_in, p);
1073         case BLKSECTGET:
1074                 return put_user(queue_max_sectors(sdp->device->request_queue) * 512,
1075                                 ip);
1076         case BLKTRACESETUP:
1077                 return blk_trace_setup(sdp->device->request_queue,
1078                                        sdp->disk->disk_name,
1079                                        MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1080                                        NULL,
1081                                        (char *)arg);
1082         case BLKTRACESTART:
1083                 return blk_trace_startstop(sdp->device->request_queue, 1);
1084         case BLKTRACESTOP:
1085                 return blk_trace_startstop(sdp->device->request_queue, 0);
1086         case BLKTRACETEARDOWN:
1087                 return blk_trace_remove(sdp->device->request_queue);
1088         default:
1089                 if (read_only)
1090                         return -EPERM;  /* don't know so take safe approach */
1091                 return scsi_ioctl(sdp->device, cmd_in, p);
1092         }
1093 }
1094
1095 #ifdef CONFIG_COMPAT
1096 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1097 {
1098         Sg_device *sdp;
1099         Sg_fd *sfp;
1100         struct scsi_device *sdev;
1101
1102         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1103                 return -ENXIO;
1104
1105         sdev = sdp->device;
1106         if (sdev->host->hostt->compat_ioctl) {
1107                 int ret;
1108
1109                 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1110
1111                 return ret;
1112         }
1113
1114         return -ENOIOCTLCMD;
1115 }
1116 #endif
1117
1118 static unsigned int
1119 sg_poll(struct file *filp, poll_table * wait)
1120 {
1121         unsigned int res = 0;
1122         Sg_device *sdp;
1123         Sg_fd *sfp;
1124         Sg_request *srp;
1125         int count = 0;
1126         unsigned long iflags;
1127
1128         sfp = filp->private_data;
1129         if (!sfp)
1130                 return POLLERR;
1131         sdp = sfp->parentdp;
1132         if (!sdp)
1133                 return POLLERR;
1134         poll_wait(filp, &sfp->read_wait, wait);
1135         read_lock_irqsave(&sfp->rq_list_lock, iflags);
1136         for (srp = sfp->headrp; srp; srp = srp->nextrp) {
1137                 /* if any read waiting, flag it */
1138                 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1139                         res = POLLIN | POLLRDNORM;
1140                 ++count;
1141         }
1142         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1143
1144         if (sdp->detached)
1145                 res |= POLLHUP;
1146         else if (!sfp->cmd_q) {
1147                 if (0 == count)
1148                         res |= POLLOUT | POLLWRNORM;
1149         } else if (count < SG_MAX_QUEUE)
1150                 res |= POLLOUT | POLLWRNORM;
1151         SCSI_LOG_TIMEOUT(3, printk("sg_poll: %s, res=0x%x\n",
1152                                    sdp->disk->disk_name, (int) res));
1153         return res;
1154 }
1155
1156 static int
1157 sg_fasync(int fd, struct file *filp, int mode)
1158 {
1159         Sg_device *sdp;
1160         Sg_fd *sfp;
1161
1162         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1163                 return -ENXIO;
1164         SCSI_LOG_TIMEOUT(3, printk("sg_fasync: %s, mode=%d\n",
1165                                    sdp->disk->disk_name, mode));
1166
1167         return fasync_helper(fd, filp, mode, &sfp->async_qp);
1168 }
1169
1170 static int
1171 sg_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1172 {
1173         Sg_fd *sfp;
1174         unsigned long offset, len, sa;
1175         Sg_scatter_hold *rsv_schp;
1176         int k, length;
1177
1178         if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1179                 return VM_FAULT_SIGBUS;
1180         rsv_schp = &sfp->reserve;
1181         offset = vmf->pgoff << PAGE_SHIFT;
1182         if (offset >= rsv_schp->bufflen)
1183                 return VM_FAULT_SIGBUS;
1184         SCSI_LOG_TIMEOUT(3, printk("sg_vma_fault: offset=%lu, scatg=%d\n",
1185                                    offset, rsv_schp->k_use_sg));
1186         sa = vma->vm_start;
1187         length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1188         for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1189                 len = vma->vm_end - sa;
1190                 len = (len < length) ? len : length;
1191                 if (offset < len) {
1192                         struct page *page = nth_page(rsv_schp->pages[k],
1193                                                      offset >> PAGE_SHIFT);
1194                         get_page(page); /* increment page count */
1195                         vmf->page = page;
1196                         return 0; /* success */
1197                 }
1198                 sa += len;
1199                 offset -= len;
1200         }
1201
1202         return VM_FAULT_SIGBUS;
1203 }
1204
1205 static const struct vm_operations_struct sg_mmap_vm_ops = {
1206         .fault = sg_vma_fault,
1207 };
1208
1209 static int
1210 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1211 {
1212         Sg_fd *sfp;
1213         unsigned long req_sz, len, sa;
1214         Sg_scatter_hold *rsv_schp;
1215         int k, length;
1216
1217         if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1218                 return -ENXIO;
1219         req_sz = vma->vm_end - vma->vm_start;
1220         SCSI_LOG_TIMEOUT(3, printk("sg_mmap starting, vm_start=%p, len=%d\n",
1221                                    (void *) vma->vm_start, (int) req_sz));
1222         if (vma->vm_pgoff)
1223                 return -EINVAL; /* want no offset */
1224         rsv_schp = &sfp->reserve;
1225         if (req_sz > rsv_schp->bufflen)
1226                 return -ENOMEM; /* cannot map more than reserved buffer */
1227
1228         sa = vma->vm_start;
1229         length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1230         for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1231                 len = vma->vm_end - sa;
1232                 len = (len < length) ? len : length;
1233                 sa += len;
1234         }
1235
1236         sfp->mmap_called = 1;
1237         vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
1238         vma->vm_private_data = sfp;
1239         vma->vm_ops = &sg_mmap_vm_ops;
1240         return 0;
1241 }
1242
1243 static void sg_rq_end_io_usercontext(struct work_struct *work)
1244 {
1245         struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1246         struct sg_fd *sfp = srp->parentfp;
1247
1248         sg_finish_rem_req(srp);
1249         kref_put(&sfp->f_ref, sg_remove_sfp);
1250 }
1251
1252 /*
1253  * This function is a "bottom half" handler that is called by the mid
1254  * level when a command is completed (or has failed).
1255  */
1256 static void sg_rq_end_io(struct request *rq, int uptodate)
1257 {
1258         struct sg_request *srp = rq->end_io_data;
1259         Sg_device *sdp;
1260         Sg_fd *sfp;
1261         unsigned long iflags;
1262         unsigned int ms;
1263         char *sense;
1264         int result, resid, done = 1;
1265
1266         if (WARN_ON(srp->done != 0))
1267                 return;
1268
1269         sfp = srp->parentfp;
1270         if (WARN_ON(sfp == NULL))
1271                 return;
1272
1273         sdp = sfp->parentdp;
1274         if (unlikely(sdp->detached))
1275                 printk(KERN_INFO "sg_rq_end_io: device detached\n");
1276
1277         sense = rq->sense;
1278         result = rq->errors;
1279         resid = rq->resid_len;
1280
1281         SCSI_LOG_TIMEOUT(4, printk("sg_cmd_done: %s, pack_id=%d, res=0x%x\n",
1282                 sdp->disk->disk_name, srp->header.pack_id, result));
1283         srp->header.resid = resid;
1284         ms = jiffies_to_msecs(jiffies);
1285         srp->header.duration = (ms > srp->header.duration) ?
1286                                 (ms - srp->header.duration) : 0;
1287         if (0 != result) {
1288                 struct scsi_sense_hdr sshdr;
1289
1290                 srp->header.status = 0xff & result;
1291                 srp->header.masked_status = status_byte(result);
1292                 srp->header.msg_status = msg_byte(result);
1293                 srp->header.host_status = host_byte(result);
1294                 srp->header.driver_status = driver_byte(result);
1295                 if ((sdp->sgdebug > 0) &&
1296                     ((CHECK_CONDITION == srp->header.masked_status) ||
1297                      (COMMAND_TERMINATED == srp->header.masked_status)))
1298                         __scsi_print_sense("sg_cmd_done", sense,
1299                                            SCSI_SENSE_BUFFERSIZE);
1300
1301                 /* Following if statement is a patch supplied by Eric Youngdale */
1302                 if (driver_byte(result) != 0
1303                     && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1304                     && !scsi_sense_is_deferred(&sshdr)
1305                     && sshdr.sense_key == UNIT_ATTENTION
1306                     && sdp->device->removable) {
1307                         /* Detected possible disc change. Set the bit - this */
1308                         /* may be used if there are filesystems using this device */
1309                         sdp->device->changed = 1;
1310                 }
1311         }
1312         /* Rely on write phase to clean out srp status values, so no "else" */
1313
1314         write_lock_irqsave(&sfp->rq_list_lock, iflags);
1315         if (unlikely(srp->orphan)) {
1316                 if (sfp->keep_orphan)
1317                         srp->sg_io_owned = 0;
1318                 else
1319                         done = 0;
1320         }
1321         srp->done = done;
1322         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1323
1324         if (likely(done)) {
1325                 /* Now wake up any sg_read() that is waiting for this
1326                  * packet.
1327                  */
1328                 wake_up_interruptible(&sfp->read_wait);
1329                 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1330                 kref_put(&sfp->f_ref, sg_remove_sfp);
1331         } else {
1332                 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1333                 schedule_work(&srp->ew.work);
1334         }
1335 }
1336
1337 static const struct file_operations sg_fops = {
1338         .owner = THIS_MODULE,
1339         .read = sg_read,
1340         .write = sg_write,
1341         .poll = sg_poll,
1342         .unlocked_ioctl = sg_ioctl,
1343 #ifdef CONFIG_COMPAT
1344         .compat_ioctl = sg_compat_ioctl,
1345 #endif
1346         .open = sg_open,
1347         .mmap = sg_mmap,
1348         .release = sg_release,
1349         .fasync = sg_fasync,
1350         .llseek = no_llseek,
1351 };
1352
1353 static struct class *sg_sysfs_class;
1354
1355 static int sg_sysfs_valid = 0;
1356
1357 static Sg_device *sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1358 {
1359         struct request_queue *q = scsidp->request_queue;
1360         Sg_device *sdp;
1361         unsigned long iflags;
1362         int error;
1363         u32 k;
1364
1365         sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1366         if (!sdp) {
1367                 printk(KERN_WARNING "kmalloc Sg_device failure\n");
1368                 return ERR_PTR(-ENOMEM);
1369         }
1370
1371         idr_preload(GFP_KERNEL);
1372         write_lock_irqsave(&sg_index_lock, iflags);
1373
1374         error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT);
1375         if (error < 0) {
1376                 if (error == -ENOSPC) {
1377                         sdev_printk(KERN_WARNING, scsidp,
1378                                     "Unable to attach sg device type=%d, minor number exceeds %d\n",
1379                                     scsidp->type, SG_MAX_DEVS - 1);
1380                         error = -ENODEV;
1381                 } else {
1382                         printk(KERN_WARNING
1383                                "idr allocation Sg_device failure: %d\n", error);
1384                 }
1385                 goto out_unlock;
1386         }
1387         k = error;
1388
1389         SCSI_LOG_TIMEOUT(3, printk("sg_alloc: dev=%d \n", k));
1390         sprintf(disk->disk_name, "sg%d", k);
1391         disk->first_minor = k;
1392         sdp->disk = disk;
1393         sdp->device = scsidp;
1394         spin_lock_init(&sdp->sfd_lock);
1395         INIT_LIST_HEAD(&sdp->sfds);
1396         init_rwsem(&sdp->o_sem);
1397         sdp->sg_tablesize = queue_max_segments(q);
1398         sdp->index = k;
1399         kref_init(&sdp->d_ref);
1400         error = 0;
1401
1402 out_unlock:
1403         write_unlock_irqrestore(&sg_index_lock, iflags);
1404         idr_preload_end();
1405
1406         if (error) {
1407                 kfree(sdp);
1408                 return ERR_PTR(error);
1409         }
1410         return sdp;
1411 }
1412
1413 static int
1414 sg_add(struct device *cl_dev, struct class_interface *cl_intf)
1415 {
1416         struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1417         struct gendisk *disk;
1418         Sg_device *sdp = NULL;
1419         struct cdev * cdev = NULL;
1420         int error;
1421         unsigned long iflags;
1422
1423         disk = alloc_disk(1);
1424         if (!disk) {
1425                 printk(KERN_WARNING "alloc_disk failed\n");
1426                 return -ENOMEM;
1427         }
1428         disk->major = SCSI_GENERIC_MAJOR;
1429
1430         error = -ENOMEM;
1431         cdev = cdev_alloc();
1432         if (!cdev) {
1433                 printk(KERN_WARNING "cdev_alloc failed\n");
1434                 goto out;
1435         }
1436         cdev->owner = THIS_MODULE;
1437         cdev->ops = &sg_fops;
1438
1439         sdp = sg_alloc(disk, scsidp);
1440         if (IS_ERR(sdp)) {
1441                 printk(KERN_WARNING "sg_alloc failed\n");
1442                 error = PTR_ERR(sdp);
1443                 goto out;
1444         }
1445
1446         error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1447         if (error)
1448                 goto cdev_add_err;
1449
1450         sdp->cdev = cdev;
1451         if (sg_sysfs_valid) {
1452                 struct device *sg_class_member;
1453
1454                 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1455                                                 MKDEV(SCSI_GENERIC_MAJOR,
1456                                                       sdp->index),
1457                                                 sdp, "%s", disk->disk_name);
1458                 if (IS_ERR(sg_class_member)) {
1459                         printk(KERN_ERR "sg_add: "
1460                                "device_create failed\n");
1461                         error = PTR_ERR(sg_class_member);
1462                         goto cdev_add_err;
1463                 }
1464                 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1465                                           &sg_class_member->kobj, "generic");
1466                 if (error)
1467                         printk(KERN_ERR "sg_add: unable to make symlink "
1468                                         "'generic' back to sg%d\n", sdp->index);
1469         } else
1470                 printk(KERN_WARNING "sg_add: sg_sys Invalid\n");
1471
1472         sdev_printk(KERN_NOTICE, scsidp,
1473                     "Attached scsi generic sg%d type %d\n", sdp->index,
1474                     scsidp->type);
1475
1476         dev_set_drvdata(cl_dev, sdp);
1477
1478         return 0;
1479
1480 cdev_add_err:
1481         write_lock_irqsave(&sg_index_lock, iflags);
1482         idr_remove(&sg_index_idr, sdp->index);
1483         write_unlock_irqrestore(&sg_index_lock, iflags);
1484         kfree(sdp);
1485
1486 out:
1487         put_disk(disk);
1488         if (cdev)
1489                 cdev_del(cdev);
1490         return error;
1491 }
1492
1493 static void sg_device_destroy(struct kref *kref)
1494 {
1495         struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1496         unsigned long flags;
1497
1498         /* CAUTION!  Note that the device can still be found via idr_find()
1499          * even though the refcount is 0.  Therefore, do idr_remove() BEFORE
1500          * any other cleanup.
1501          */
1502
1503         write_lock_irqsave(&sg_index_lock, flags);
1504         idr_remove(&sg_index_idr, sdp->index);
1505         write_unlock_irqrestore(&sg_index_lock, flags);
1506
1507         SCSI_LOG_TIMEOUT(3,
1508                 printk("sg_device_destroy: %s\n",
1509                         sdp->disk->disk_name));
1510
1511         put_disk(sdp->disk);
1512         kfree(sdp);
1513 }
1514
1515 static void sg_remove(struct device *cl_dev, struct class_interface *cl_intf)
1516 {
1517         struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1518         Sg_device *sdp = dev_get_drvdata(cl_dev);
1519         unsigned long iflags;
1520         Sg_fd *sfp;
1521
1522         if (!sdp || sdp->detached)
1523                 return;
1524
1525         SCSI_LOG_TIMEOUT(3, printk("sg_remove: %s\n", sdp->disk->disk_name));
1526
1527         /* Need a write lock to set sdp->detached. */
1528         write_lock_irqsave(&sg_index_lock, iflags);
1529         spin_lock(&sdp->sfd_lock);
1530         sdp->detached = 1;
1531         list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1532                 wake_up_interruptible(&sfp->read_wait);
1533                 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1534         }
1535         spin_unlock(&sdp->sfd_lock);
1536         write_unlock_irqrestore(&sg_index_lock, iflags);
1537
1538         sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1539         device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1540         cdev_del(sdp->cdev);
1541         sdp->cdev = NULL;
1542
1543         sg_put_dev(sdp);
1544 }
1545
1546 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1547 module_param_named(def_reserved_size, def_reserved_size, int,
1548                    S_IRUGO | S_IWUSR);
1549 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1550
1551 MODULE_AUTHOR("Douglas Gilbert");
1552 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1553 MODULE_LICENSE("GPL");
1554 MODULE_VERSION(SG_VERSION_STR);
1555 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1556
1557 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1558                 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1559 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1560 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1561
1562 static int __init
1563 init_sg(void)
1564 {
1565         int rc;
1566
1567         if (scatter_elem_sz < PAGE_SIZE) {
1568                 scatter_elem_sz = PAGE_SIZE;
1569                 scatter_elem_sz_prev = scatter_elem_sz;
1570         }
1571         if (def_reserved_size >= 0)
1572                 sg_big_buff = def_reserved_size;
1573         else
1574                 def_reserved_size = sg_big_buff;
1575
1576         rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1577                                     SG_MAX_DEVS, "sg");
1578         if (rc)
1579                 return rc;
1580         sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1581         if ( IS_ERR(sg_sysfs_class) ) {
1582                 rc = PTR_ERR(sg_sysfs_class);
1583                 goto err_out;
1584         }
1585         sg_sysfs_valid = 1;
1586         rc = scsi_register_interface(&sg_interface);
1587         if (0 == rc) {
1588 #ifdef CONFIG_SCSI_PROC_FS
1589                 sg_proc_init();
1590 #endif                          /* CONFIG_SCSI_PROC_FS */
1591                 return 0;
1592         }
1593         class_destroy(sg_sysfs_class);
1594 err_out:
1595         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1596         return rc;
1597 }
1598
1599 static void __exit
1600 exit_sg(void)
1601 {
1602 #ifdef CONFIG_SCSI_PROC_FS
1603         sg_proc_cleanup();
1604 #endif                          /* CONFIG_SCSI_PROC_FS */
1605         scsi_unregister_interface(&sg_interface);
1606         class_destroy(sg_sysfs_class);
1607         sg_sysfs_valid = 0;
1608         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1609                                  SG_MAX_DEVS);
1610         idr_destroy(&sg_index_idr);
1611 }
1612
1613 static int sg_start_req(Sg_request *srp, unsigned char *cmd)
1614 {
1615         int res;
1616         struct request *rq;
1617         Sg_fd *sfp = srp->parentfp;
1618         sg_io_hdr_t *hp = &srp->header;
1619         int dxfer_len = (int) hp->dxfer_len;
1620         int dxfer_dir = hp->dxfer_direction;
1621         unsigned int iov_count = hp->iovec_count;
1622         Sg_scatter_hold *req_schp = &srp->data;
1623         Sg_scatter_hold *rsv_schp = &sfp->reserve;
1624         struct request_queue *q = sfp->parentdp->device->request_queue;
1625         struct rq_map_data *md, map_data;
1626         int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
1627
1628         SCSI_LOG_TIMEOUT(4, printk(KERN_INFO "sg_start_req: dxfer_len=%d\n",
1629                                    dxfer_len));
1630
1631         rq = blk_get_request(q, rw, GFP_ATOMIC);
1632         if (!rq)
1633                 return -ENOMEM;
1634
1635         memcpy(rq->cmd, cmd, hp->cmd_len);
1636
1637         rq->cmd_len = hp->cmd_len;
1638         rq->cmd_type = REQ_TYPE_BLOCK_PC;
1639
1640         srp->rq = rq;
1641         rq->end_io_data = srp;
1642         rq->sense = srp->sense_b;
1643         rq->retries = SG_DEFAULT_RETRIES;
1644
1645         if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1646                 return 0;
1647
1648         if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1649             dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1650             !sfp->parentdp->device->host->unchecked_isa_dma &&
1651             blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))
1652                 md = NULL;
1653         else
1654                 md = &map_data;
1655
1656         if (md) {
1657                 if (!sg_res_in_use(sfp) && dxfer_len <= rsv_schp->bufflen)
1658                         sg_link_reserve(sfp, srp, dxfer_len);
1659                 else {
1660                         res = sg_build_indirect(req_schp, sfp, dxfer_len);
1661                         if (res)
1662                                 return res;
1663                 }
1664
1665                 md->pages = req_schp->pages;
1666                 md->page_order = req_schp->page_order;
1667                 md->nr_entries = req_schp->k_use_sg;
1668                 md->offset = 0;
1669                 md->null_mapped = hp->dxferp ? 0 : 1;
1670                 if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1671                         md->from_user = 1;
1672                 else
1673                         md->from_user = 0;
1674         }
1675
1676         if (iov_count) {
1677                 int len, size = sizeof(struct sg_iovec) * iov_count;
1678                 struct iovec *iov;
1679
1680                 iov = memdup_user(hp->dxferp, size);
1681                 if (IS_ERR(iov))
1682                         return PTR_ERR(iov);
1683
1684                 len = iov_length(iov, iov_count);
1685                 if (hp->dxfer_len < len) {
1686                         iov_count = iov_shorten(iov, iov_count, hp->dxfer_len);
1687                         len = hp->dxfer_len;
1688                 }
1689
1690                 res = blk_rq_map_user_iov(q, rq, md, (struct sg_iovec *)iov,
1691                                           iov_count,
1692                                           len, GFP_ATOMIC);
1693                 kfree(iov);
1694         } else
1695                 res = blk_rq_map_user(q, rq, md, hp->dxferp,
1696                                       hp->dxfer_len, GFP_ATOMIC);
1697
1698         if (!res) {
1699                 srp->bio = rq->bio;
1700
1701                 if (!md) {
1702                         req_schp->dio_in_use = 1;
1703                         hp->info |= SG_INFO_DIRECT_IO;
1704                 }
1705         }
1706         return res;
1707 }
1708
1709 static int sg_finish_rem_req(Sg_request * srp)
1710 {
1711         int ret = 0;
1712
1713         Sg_fd *sfp = srp->parentfp;
1714         Sg_scatter_hold *req_schp = &srp->data;
1715
1716         SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n", (int) srp->res_used));
1717         if (srp->rq) {
1718                 if (srp->bio)
1719                         ret = blk_rq_unmap_user(srp->bio);
1720
1721                 blk_put_request(srp->rq);
1722         }
1723
1724         if (srp->res_used)
1725                 sg_unlink_reserve(sfp, srp);
1726         else
1727                 sg_remove_scat(req_schp);
1728
1729         sg_remove_request(sfp, srp);
1730
1731         return ret;
1732 }
1733
1734 static int
1735 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1736 {
1737         int sg_bufflen = tablesize * sizeof(struct page *);
1738         gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1739
1740         schp->pages = kzalloc(sg_bufflen, gfp_flags);
1741         if (!schp->pages)
1742                 return -ENOMEM;
1743         schp->sglist_len = sg_bufflen;
1744         return tablesize;       /* number of scat_gath elements allocated */
1745 }
1746
1747 static int
1748 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1749 {
1750         int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1751         int sg_tablesize = sfp->parentdp->sg_tablesize;
1752         int blk_size = buff_size, order;
1753         gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
1754
1755         if (blk_size < 0)
1756                 return -EFAULT;
1757         if (0 == blk_size)
1758                 ++blk_size;     /* don't know why */
1759         /* round request up to next highest SG_SECTOR_SZ byte boundary */
1760         blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1761         SCSI_LOG_TIMEOUT(4, printk("sg_build_indirect: buff_size=%d, blk_size=%d\n",
1762                                    buff_size, blk_size));
1763
1764         /* N.B. ret_sz carried into this block ... */
1765         mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1766         if (mx_sc_elems < 0)
1767                 return mx_sc_elems;     /* most likely -ENOMEM */
1768
1769         num = scatter_elem_sz;
1770         if (unlikely(num != scatter_elem_sz_prev)) {
1771                 if (num < PAGE_SIZE) {
1772                         scatter_elem_sz = PAGE_SIZE;
1773                         scatter_elem_sz_prev = PAGE_SIZE;
1774                 } else
1775                         scatter_elem_sz_prev = num;
1776         }
1777
1778         if (sfp->low_dma)
1779                 gfp_mask |= GFP_DMA;
1780
1781         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1782                 gfp_mask |= __GFP_ZERO;
1783
1784         order = get_order(num);
1785 retry:
1786         ret_sz = 1 << (PAGE_SHIFT + order);
1787
1788         for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1789              k++, rem_sz -= ret_sz) {
1790
1791                 num = (rem_sz > scatter_elem_sz_prev) ?
1792                         scatter_elem_sz_prev : rem_sz;
1793
1794                 schp->pages[k] = alloc_pages(gfp_mask, order);
1795                 if (!schp->pages[k])
1796                         goto out;
1797
1798                 if (num == scatter_elem_sz_prev) {
1799                         if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1800                                 scatter_elem_sz = ret_sz;
1801                                 scatter_elem_sz_prev = ret_sz;
1802                         }
1803                 }
1804
1805                 SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k=%d, num=%d, "
1806                                  "ret_sz=%d\n", k, num, ret_sz));
1807         }               /* end of for loop */
1808
1809         schp->page_order = order;
1810         schp->k_use_sg = k;
1811         SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, "
1812                          "rem_sz=%d\n", k, rem_sz));
1813
1814         schp->bufflen = blk_size;
1815         if (rem_sz > 0) /* must have failed */
1816                 return -ENOMEM;
1817         return 0;
1818 out:
1819         for (i = 0; i < k; i++)
1820                 __free_pages(schp->pages[i], order);
1821
1822         if (--order >= 0)
1823                 goto retry;
1824
1825         return -ENOMEM;
1826 }
1827
1828 static void
1829 sg_remove_scat(Sg_scatter_hold * schp)
1830 {
1831         SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1832         if (schp->pages && schp->sglist_len > 0) {
1833                 if (!schp->dio_in_use) {
1834                         int k;
1835
1836                         for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1837                                 SCSI_LOG_TIMEOUT(5, printk(
1838                                     "sg_remove_scat: k=%d, pg=0x%p\n",
1839                                     k, schp->pages[k]));
1840                                 __free_pages(schp->pages[k], schp->page_order);
1841                         }
1842
1843                         kfree(schp->pages);
1844                 }
1845         }
1846         memset(schp, 0, sizeof (*schp));
1847 }
1848
1849 static int
1850 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1851 {
1852         Sg_scatter_hold *schp = &srp->data;
1853         int k, num;
1854
1855         SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n",
1856                                    num_read_xfer));
1857         if ((!outp) || (num_read_xfer <= 0))
1858                 return 0;
1859
1860         num = 1 << (PAGE_SHIFT + schp->page_order);
1861         for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1862                 if (num > num_read_xfer) {
1863                         if (__copy_to_user(outp, page_address(schp->pages[k]),
1864                                            num_read_xfer))
1865                                 return -EFAULT;
1866                         break;
1867                 } else {
1868                         if (__copy_to_user(outp, page_address(schp->pages[k]),
1869                                            num))
1870                                 return -EFAULT;
1871                         num_read_xfer -= num;
1872                         if (num_read_xfer <= 0)
1873                                 break;
1874                         outp += num;
1875                 }
1876         }
1877
1878         return 0;
1879 }
1880
1881 static void
1882 sg_build_reserve(Sg_fd * sfp, int req_size)
1883 {
1884         Sg_scatter_hold *schp = &sfp->reserve;
1885
1886         SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
1887         do {
1888                 if (req_size < PAGE_SIZE)
1889                         req_size = PAGE_SIZE;
1890                 if (0 == sg_build_indirect(schp, sfp, req_size))
1891                         return;
1892                 else
1893                         sg_remove_scat(schp);
1894                 req_size >>= 1; /* divide by 2 */
1895         } while (req_size > (PAGE_SIZE / 2));
1896 }
1897
1898 static void
1899 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
1900 {
1901         Sg_scatter_hold *req_schp = &srp->data;
1902         Sg_scatter_hold *rsv_schp = &sfp->reserve;
1903         int k, num, rem;
1904
1905         srp->res_used = 1;
1906         SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
1907         rem = size;
1908
1909         num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1910         for (k = 0; k < rsv_schp->k_use_sg; k++) {
1911                 if (rem <= num) {
1912                         req_schp->k_use_sg = k + 1;
1913                         req_schp->sglist_len = rsv_schp->sglist_len;
1914                         req_schp->pages = rsv_schp->pages;
1915
1916                         req_schp->bufflen = size;
1917                         req_schp->page_order = rsv_schp->page_order;
1918                         break;
1919                 } else
1920                         rem -= num;
1921         }
1922
1923         if (k >= rsv_schp->k_use_sg)
1924                 SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
1925 }
1926
1927 static void
1928 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
1929 {
1930         Sg_scatter_hold *req_schp = &srp->data;
1931
1932         SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->k_use_sg=%d\n",
1933                                    (int) req_schp->k_use_sg));
1934         req_schp->k_use_sg = 0;
1935         req_schp->bufflen = 0;
1936         req_schp->pages = NULL;
1937         req_schp->page_order = 0;
1938         req_schp->sglist_len = 0;
1939         sfp->save_scat_len = 0;
1940         srp->res_used = 0;
1941 }
1942
1943 static Sg_request *
1944 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
1945 {
1946         Sg_request *resp;
1947         unsigned long iflags;
1948
1949         write_lock_irqsave(&sfp->rq_list_lock, iflags);
1950         for (resp = sfp->headrp; resp; resp = resp->nextrp) {
1951                 /* look for requests that are ready + not SG_IO owned */
1952                 if ((1 == resp->done) && (!resp->sg_io_owned) &&
1953                     ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
1954                         resp->done = 2; /* guard against other readers */
1955                         break;
1956                 }
1957         }
1958         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1959         return resp;
1960 }
1961
1962 /* always adds to end of list */
1963 static Sg_request *
1964 sg_add_request(Sg_fd * sfp)
1965 {
1966         int k;
1967         unsigned long iflags;
1968         Sg_request *resp;
1969         Sg_request *rp = sfp->req_arr;
1970
1971         write_lock_irqsave(&sfp->rq_list_lock, iflags);
1972         resp = sfp->headrp;
1973         if (!resp) {
1974                 memset(rp, 0, sizeof (Sg_request));
1975                 rp->parentfp = sfp;
1976                 resp = rp;
1977                 sfp->headrp = resp;
1978         } else {
1979                 if (0 == sfp->cmd_q)
1980                         resp = NULL;    /* command queuing disallowed */
1981                 else {
1982                         for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
1983                                 if (!rp->parentfp)
1984                                         break;
1985                         }
1986                         if (k < SG_MAX_QUEUE) {
1987                                 memset(rp, 0, sizeof (Sg_request));
1988                                 rp->parentfp = sfp;
1989                                 while (resp->nextrp)
1990                                         resp = resp->nextrp;
1991                                 resp->nextrp = rp;
1992                                 resp = rp;
1993                         } else
1994                                 resp = NULL;
1995                 }
1996         }
1997         if (resp) {
1998                 resp->nextrp = NULL;
1999                 resp->header.duration = jiffies_to_msecs(jiffies);
2000         }
2001         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2002         return resp;
2003 }
2004
2005 /* Return of 1 for found; 0 for not found */
2006 static int
2007 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2008 {
2009         Sg_request *prev_rp;
2010         Sg_request *rp;
2011         unsigned long iflags;
2012         int res = 0;
2013
2014         if ((!sfp) || (!srp) || (!sfp->headrp))
2015                 return res;
2016         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2017         prev_rp = sfp->headrp;
2018         if (srp == prev_rp) {
2019                 sfp->headrp = prev_rp->nextrp;
2020                 prev_rp->parentfp = NULL;
2021                 res = 1;
2022         } else {
2023                 while ((rp = prev_rp->nextrp)) {
2024                         if (srp == rp) {
2025                                 prev_rp->nextrp = rp->nextrp;
2026                                 rp->parentfp = NULL;
2027                                 res = 1;
2028                                 break;
2029                         }
2030                         prev_rp = rp;
2031                 }
2032         }
2033         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2034         return res;
2035 }
2036
2037 static Sg_fd *
2038 sg_add_sfp(Sg_device * sdp, int dev)
2039 {
2040         Sg_fd *sfp;
2041         unsigned long iflags;
2042         int bufflen;
2043
2044         sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2045         if (!sfp)
2046                 return ERR_PTR(-ENOMEM);
2047
2048         init_waitqueue_head(&sfp->read_wait);
2049         rwlock_init(&sfp->rq_list_lock);
2050
2051         kref_init(&sfp->f_ref);
2052         sfp->timeout = SG_DEFAULT_TIMEOUT;
2053         sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2054         sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2055         sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
2056             sdp->device->host->unchecked_isa_dma : 1;
2057         sfp->cmd_q = SG_DEF_COMMAND_Q;
2058         sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2059         sfp->parentdp = sdp;
2060         spin_lock_irqsave(&sdp->sfd_lock, iflags);
2061         if (sdp->detached) {
2062                 spin_unlock_irqrestore(&sdp->sfd_lock, iflags);
2063                 return ERR_PTR(-ENODEV);
2064         }
2065         list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2066         spin_unlock_irqrestore(&sdp->sfd_lock, iflags);
2067         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));
2068         if (unlikely(sg_big_buff != def_reserved_size))
2069                 sg_big_buff = def_reserved_size;
2070
2071         bufflen = min_t(int, sg_big_buff,
2072                         queue_max_sectors(sdp->device->request_queue) * 512);
2073         sg_build_reserve(sfp, bufflen);
2074         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp:   bufflen=%d, k_use_sg=%d\n",
2075                            sfp->reserve.bufflen, sfp->reserve.k_use_sg));
2076
2077         kref_get(&sdp->d_ref);
2078         __module_get(THIS_MODULE);
2079         return sfp;
2080 }
2081
2082 static void sg_remove_sfp_usercontext(struct work_struct *work)
2083 {
2084         struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2085         struct sg_device *sdp = sfp->parentdp;
2086
2087         /* Cleanup any responses which were never read(). */
2088         while (sfp->headrp)
2089                 sg_finish_rem_req(sfp->headrp);
2090
2091         if (sfp->reserve.bufflen > 0) {
2092                 SCSI_LOG_TIMEOUT(6,
2093                         printk("sg_remove_sfp:    bufflen=%d, k_use_sg=%d\n",
2094                                 (int) sfp->reserve.bufflen,
2095                                 (int) sfp->reserve.k_use_sg));
2096                 sg_remove_scat(&sfp->reserve);
2097         }
2098
2099         SCSI_LOG_TIMEOUT(6,
2100                 printk("sg_remove_sfp: %s, sfp=0x%p\n",
2101                         sdp->disk->disk_name,
2102                         sfp));
2103         kfree(sfp);
2104
2105         scsi_device_put(sdp->device);
2106         sg_put_dev(sdp);
2107         module_put(THIS_MODULE);
2108 }
2109
2110 static void sg_remove_sfp(struct kref *kref)
2111 {
2112         struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2113         struct sg_device *sdp = sfp->parentdp;
2114         unsigned long iflags;
2115
2116         spin_lock_irqsave(&sdp->sfd_lock, iflags);
2117         list_del(&sfp->sfd_siblings);
2118         spin_unlock_irqrestore(&sdp->sfd_lock, iflags);
2119
2120         INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2121         schedule_work(&sfp->ew.work);
2122 }
2123
2124 static int
2125 sg_res_in_use(Sg_fd * sfp)
2126 {
2127         const Sg_request *srp;
2128         unsigned long iflags;
2129
2130         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2131         for (srp = sfp->headrp; srp; srp = srp->nextrp)
2132                 if (srp->res_used)
2133                         break;
2134         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2135         return srp ? 1 : 0;
2136 }
2137
2138 #ifdef CONFIG_SCSI_PROC_FS
2139 static int
2140 sg_idr_max_id(int id, void *p, void *data)
2141 {
2142         int *k = data;
2143
2144         if (*k < id)
2145                 *k = id;
2146
2147         return 0;
2148 }
2149
2150 static int
2151 sg_last_dev(void)
2152 {
2153         int k = -1;
2154         unsigned long iflags;
2155
2156         read_lock_irqsave(&sg_index_lock, iflags);
2157         idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2158         read_unlock_irqrestore(&sg_index_lock, iflags);
2159         return k + 1;           /* origin 1 */
2160 }
2161 #endif
2162
2163 /* must be called with sg_index_lock held */
2164 static Sg_device *sg_lookup_dev(int dev)
2165 {
2166         return idr_find(&sg_index_idr, dev);
2167 }
2168
2169 static Sg_device *sg_get_dev(int dev)
2170 {
2171         struct sg_device *sdp;
2172         unsigned long flags;
2173
2174         read_lock_irqsave(&sg_index_lock, flags);
2175         sdp = sg_lookup_dev(dev);
2176         if (!sdp)
2177                 sdp = ERR_PTR(-ENXIO);
2178         else if (sdp->detached) {
2179                 /* If sdp->detached, then the refcount may already be 0, in
2180                  * which case it would be a bug to do kref_get().
2181                  */
2182                 sdp = ERR_PTR(-ENODEV);
2183         } else
2184                 kref_get(&sdp->d_ref);
2185         read_unlock_irqrestore(&sg_index_lock, flags);
2186
2187         return sdp;
2188 }
2189
2190 static void sg_put_dev(struct sg_device *sdp)
2191 {
2192         kref_put(&sdp->d_ref, sg_device_destroy);
2193 }
2194
2195 #ifdef CONFIG_SCSI_PROC_FS
2196
2197 static struct proc_dir_entry *sg_proc_sgp = NULL;
2198
2199 static char sg_proc_sg_dirname[] = "scsi/sg";
2200
2201 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2202
2203 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2204 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2205                                   size_t count, loff_t *off);
2206 static const struct file_operations adio_fops = {
2207         .owner = THIS_MODULE,
2208         .open = sg_proc_single_open_adio,
2209         .read = seq_read,
2210         .llseek = seq_lseek,
2211         .write = sg_proc_write_adio,
2212         .release = single_release,
2213 };
2214
2215 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2216 static ssize_t sg_proc_write_dressz(struct file *filp,
2217                 const char __user *buffer, size_t count, loff_t *off);
2218 static const struct file_operations dressz_fops = {
2219         .owner = THIS_MODULE,
2220         .open = sg_proc_single_open_dressz,
2221         .read = seq_read,
2222         .llseek = seq_lseek,
2223         .write = sg_proc_write_dressz,
2224         .release = single_release,
2225 };
2226
2227 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2228 static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2229 static const struct file_operations version_fops = {
2230         .owner = THIS_MODULE,
2231         .open = sg_proc_single_open_version,
2232         .read = seq_read,
2233         .llseek = seq_lseek,
2234         .release = single_release,
2235 };
2236
2237 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2238 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2239 static const struct file_operations devhdr_fops = {
2240         .owner = THIS_MODULE,
2241         .open = sg_proc_single_open_devhdr,
2242         .read = seq_read,
2243         .llseek = seq_lseek,
2244         .release = single_release,
2245 };
2246
2247 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2248 static int sg_proc_open_dev(struct inode *inode, struct file *file);
2249 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2250 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2251 static void dev_seq_stop(struct seq_file *s, void *v);
2252 static const struct file_operations dev_fops = {
2253         .owner = THIS_MODULE,
2254         .open = sg_proc_open_dev,
2255         .read = seq_read,
2256         .llseek = seq_lseek,
2257         .release = seq_release,
2258 };
2259 static const struct seq_operations dev_seq_ops = {
2260         .start = dev_seq_start,
2261         .next  = dev_seq_next,
2262         .stop  = dev_seq_stop,
2263         .show  = sg_proc_seq_show_dev,
2264 };
2265
2266 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2267 static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2268 static const struct file_operations devstrs_fops = {
2269         .owner = THIS_MODULE,
2270         .open = sg_proc_open_devstrs,
2271         .read = seq_read,
2272         .llseek = seq_lseek,
2273         .release = seq_release,
2274 };
2275 static const struct seq_operations devstrs_seq_ops = {
2276         .start = dev_seq_start,
2277         .next  = dev_seq_next,
2278         .stop  = dev_seq_stop,
2279         .show  = sg_proc_seq_show_devstrs,
2280 };
2281
2282 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2283 static int sg_proc_open_debug(struct inode *inode, struct file *file);
2284 static const struct file_operations debug_fops = {
2285         .owner = THIS_MODULE,
2286         .open = sg_proc_open_debug,
2287         .read = seq_read,
2288         .llseek = seq_lseek,
2289         .release = seq_release,
2290 };
2291 static const struct seq_operations debug_seq_ops = {
2292         .start = dev_seq_start,
2293         .next  = dev_seq_next,
2294         .stop  = dev_seq_stop,
2295         .show  = sg_proc_seq_show_debug,
2296 };
2297
2298
2299 struct sg_proc_leaf {
2300         const char * name;
2301         const struct file_operations * fops;
2302 };
2303
2304 static const struct sg_proc_leaf sg_proc_leaf_arr[] = {
2305         {"allow_dio", &adio_fops},
2306         {"debug", &debug_fops},
2307         {"def_reserved_size", &dressz_fops},
2308         {"device_hdr", &devhdr_fops},
2309         {"devices", &dev_fops},
2310         {"device_strs", &devstrs_fops},
2311         {"version", &version_fops}
2312 };
2313
2314 static int
2315 sg_proc_init(void)
2316 {
2317         int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2318         int k;
2319
2320         sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2321         if (!sg_proc_sgp)
2322                 return 1;
2323         for (k = 0; k < num_leaves; ++k) {
2324                 const struct sg_proc_leaf *leaf = &sg_proc_leaf_arr[k];
2325                 umode_t mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2326                 proc_create(leaf->name, mask, sg_proc_sgp, leaf->fops);
2327         }
2328         return 0;
2329 }
2330
2331 static void
2332 sg_proc_cleanup(void)
2333 {
2334         int k;
2335         int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2336
2337         if (!sg_proc_sgp)
2338                 return;
2339         for (k = 0; k < num_leaves; ++k)
2340                 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2341         remove_proc_entry(sg_proc_sg_dirname, NULL);
2342 }
2343
2344
2345 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2346 {
2347         seq_printf(s, "%d\n", *((int *)s->private));
2348         return 0;
2349 }
2350
2351 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2352 {
2353         return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2354 }
2355
2356 static ssize_t
2357 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2358                    size_t count, loff_t *off)
2359 {
2360         int err;
2361         unsigned long num;
2362
2363         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2364                 return -EACCES;
2365         err = kstrtoul_from_user(buffer, count, 0, &num);
2366         if (err)
2367                 return err;
2368         sg_allow_dio = num ? 1 : 0;
2369         return count;
2370 }
2371
2372 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2373 {
2374         return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2375 }
2376
2377 static ssize_t
2378 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2379                      size_t count, loff_t *off)
2380 {
2381         int err;
2382         unsigned long k = ULONG_MAX;
2383
2384         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2385                 return -EACCES;
2386
2387         err = kstrtoul_from_user(buffer, count, 0, &k);
2388         if (err)
2389                 return err;
2390         if (k <= 1048576) {     /* limit "big buff" to 1 MB */
2391                 sg_big_buff = k;
2392                 return count;
2393         }
2394         return -ERANGE;
2395 }
2396
2397 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2398 {
2399         seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2400                    sg_version_date);
2401         return 0;
2402 }
2403
2404 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2405 {
2406         return single_open(file, sg_proc_seq_show_version, NULL);
2407 }
2408
2409 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2410 {
2411         seq_printf(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\t"
2412                    "online\n");
2413         return 0;
2414 }
2415
2416 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2417 {
2418         return single_open(file, sg_proc_seq_show_devhdr, NULL);
2419 }
2420
2421 struct sg_proc_deviter {
2422         loff_t  index;
2423         size_t  max;
2424 };
2425
2426 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2427 {
2428         struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2429
2430         s->private = it;
2431         if (! it)
2432                 return NULL;
2433
2434         it->index = *pos;
2435         it->max = sg_last_dev();
2436         if (it->index >= it->max)
2437                 return NULL;
2438         return it;
2439 }
2440
2441 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2442 {
2443         struct sg_proc_deviter * it = s->private;
2444
2445         *pos = ++it->index;
2446         return (it->index < it->max) ? it : NULL;
2447 }
2448
2449 static void dev_seq_stop(struct seq_file *s, void *v)
2450 {
2451         kfree(s->private);
2452 }
2453
2454 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2455 {
2456         return seq_open(file, &dev_seq_ops);
2457 }
2458
2459 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2460 {
2461         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2462         Sg_device *sdp;
2463         struct scsi_device *scsidp;
2464         unsigned long iflags;
2465
2466         read_lock_irqsave(&sg_index_lock, iflags);
2467         sdp = it ? sg_lookup_dev(it->index) : NULL;
2468         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2469                 seq_printf(s, "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n",
2470                               scsidp->host->host_no, scsidp->channel,
2471                               scsidp->id, scsidp->lun, (int) scsidp->type,
2472                               1,
2473                               (int) scsidp->queue_depth,
2474                               (int) scsidp->device_busy,
2475                               (int) scsi_device_online(scsidp));
2476         else
2477                 seq_printf(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2478         read_unlock_irqrestore(&sg_index_lock, iflags);
2479         return 0;
2480 }
2481
2482 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2483 {
2484         return seq_open(file, &devstrs_seq_ops);
2485 }
2486
2487 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2488 {
2489         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2490         Sg_device *sdp;
2491         struct scsi_device *scsidp;
2492         unsigned long iflags;
2493
2494         read_lock_irqsave(&sg_index_lock, iflags);
2495         sdp = it ? sg_lookup_dev(it->index) : NULL;
2496         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2497                 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2498                            scsidp->vendor, scsidp->model, scsidp->rev);
2499         else
2500                 seq_printf(s, "<no active device>\n");
2501         read_unlock_irqrestore(&sg_index_lock, iflags);
2502         return 0;
2503 }
2504
2505 /* must be called while holding sg_index_lock and sfd_lock */
2506 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2507 {
2508         int k, m, new_interface, blen, usg;
2509         Sg_request *srp;
2510         Sg_fd *fp;
2511         const sg_io_hdr_t *hp;
2512         const char * cp;
2513         unsigned int ms;
2514
2515         k = 0;
2516         list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2517                 k++;
2518                 read_lock(&fp->rq_list_lock); /* irqs already disabled */
2519                 seq_printf(s, "   FD(%d): timeout=%dms bufflen=%d "
2520                            "(res)sgat=%d low_dma=%d\n", k,
2521                            jiffies_to_msecs(fp->timeout),
2522                            fp->reserve.bufflen,
2523                            (int) fp->reserve.k_use_sg,
2524                            (int) fp->low_dma);
2525                 seq_printf(s, "   cmd_q=%d f_packid=%d k_orphan=%d closed=0\n",
2526                            (int) fp->cmd_q, (int) fp->force_packid,
2527                            (int) fp->keep_orphan);
2528                 for (m = 0, srp = fp->headrp;
2529                                 srp != NULL;
2530                                 ++m, srp = srp->nextrp) {
2531                         hp = &srp->header;
2532                         new_interface = (hp->interface_id == '\0') ? 0 : 1;
2533                         if (srp->res_used) {
2534                                 if (new_interface &&
2535                                     (SG_FLAG_MMAP_IO & hp->flags))
2536                                         cp = "     mmap>> ";
2537                                 else
2538                                         cp = "     rb>> ";
2539                         } else {
2540                                 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2541                                         cp = "     dio>> ";
2542                                 else
2543                                         cp = "     ";
2544                         }
2545                         seq_printf(s, cp);
2546                         blen = srp->data.bufflen;
2547                         usg = srp->data.k_use_sg;
2548                         seq_printf(s, srp->done ?
2549                                    ((1 == srp->done) ?  "rcv:" : "fin:")
2550                                    : "act:");
2551                         seq_printf(s, " id=%d blen=%d",
2552                                    srp->header.pack_id, blen);
2553                         if (srp->done)
2554                                 seq_printf(s, " dur=%d", hp->duration);
2555                         else {
2556                                 ms = jiffies_to_msecs(jiffies);
2557                                 seq_printf(s, " t_o/elap=%d/%d",
2558                                         (new_interface ? hp->timeout :
2559                                                   jiffies_to_msecs(fp->timeout)),
2560                                         (ms > hp->duration ? ms - hp->duration : 0));
2561                         }
2562                         seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2563                                    (int) srp->data.cmd_opcode);
2564                 }
2565                 if (0 == m)
2566                         seq_printf(s, "     No requests active\n");
2567                 read_unlock(&fp->rq_list_lock);
2568         }
2569 }
2570
2571 static int sg_proc_open_debug(struct inode *inode, struct file *file)
2572 {
2573         return seq_open(file, &debug_seq_ops);
2574 }
2575
2576 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2577 {
2578         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2579         Sg_device *sdp;
2580         unsigned long iflags;
2581
2582         if (it && (0 == it->index)) {
2583                 seq_printf(s, "max_active_device=%d(origin 1)\n",
2584                            (int)it->max);
2585                 seq_printf(s, " def_reserved_size=%d\n", sg_big_buff);
2586         }
2587
2588         read_lock_irqsave(&sg_index_lock, iflags);
2589         sdp = it ? sg_lookup_dev(it->index) : NULL;
2590         if (sdp) {
2591                 spin_lock(&sdp->sfd_lock);
2592                 if (!list_empty(&sdp->sfds)) {
2593                         struct scsi_device *scsidp = sdp->device;
2594
2595                         seq_printf(s, " >>> device=%s ", sdp->disk->disk_name);
2596                         if (sdp->detached)
2597                                 seq_printf(s, "detached pending close ");
2598                         else
2599                                 seq_printf
2600                                     (s, "scsi%d chan=%d id=%d lun=%d   em=%d",
2601                                      scsidp->host->host_no,
2602                                      scsidp->channel, scsidp->id,
2603                                      scsidp->lun,
2604                                      scsidp->host->hostt->emulated);
2605                         seq_printf(s, " sg_tablesize=%d excl=%d\n",
2606                                    sdp->sg_tablesize, sdp->exclude);
2607                         sg_proc_debug_helper(s, sdp);
2608                 }
2609                 spin_unlock(&sdp->sfd_lock);
2610         }
2611         read_unlock_irqrestore(&sg_index_lock, iflags);
2612         return 0;
2613 }
2614
2615 #endif                          /* CONFIG_SCSI_PROC_FS */
2616
2617 module_init(init_sg);
2618 module_exit(exit_sg);