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