drivers/scsi/sg.c

   1 /*
   2  *  History:
   3  *  Started: Aug 9 by Lawrence Foard (entropy@world.std.com),
   4  *           to allow user process control of SCSI devices.
   5  *  Development Sponsored by Killy Corp. NY NY
   6  *
   7  * Original driver (sg.c):
   8  *        Copyright (C) 1992 Lawrence Foard
   9  * Version 2 and 3 extensions to driver:
  10  *        Copyright (C) 1998 - 2005 Douglas Gilbert
  11  *
  12  *  Modified  19-JAN-1998  Richard Gooch <rgooch@atnf.csiro.au>  Devfs support
  13  *
  14  * This program is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2, or (at your option)
  17  * any later version.
  18  *
  19  */
  20
  21 static int sg_version_num = 30534;      /* 2 digits for each component */
  22 #define SG_VERSION_STR "3.5.34"
  23
  24 /*
  25  *  D. P. Gilbert (dgilbert@interlog.com, dougg@triode.net.au), notes:
  26  *      - scsi logging is available via SCSI_LOG_TIMEOUT macros. First
  27  *        the kernel/module needs to be built with CONFIG_SCSI_LOGGING
  28  *        (otherwise the macros compile to empty statements).
  29  *
  30  */
  31 #include <linux/module.h>
  32
  33 #include <linux/fs.h>
  34 #include <linux/kernel.h>
  35 #include <linux/sched.h>
  36 #include <linux/string.h>
  37 #include <linux/mm.h>
  38 #include <linux/errno.h>
  39 #include <linux/mtio.h>
  40 #include <linux/ioctl.h>
  41 #include <linux/slab.h>
  42 #include <linux/fcntl.h>
  43 #include <linux/init.h>
  44 #include <linux/poll.h>
  45 #include <linux/moduleparam.h>
  46 #include <linux/cdev.h>
  47 #include <linux/idr.h>
  48 #include <linux/seq_file.h>
  49 #include <linux/blkdev.h>
  50 #include <linux/delay.h>
  51 #include <linux/blktrace_api.h>
  52 #include <linux/smp_lock.h>
  53
  54 #include "scsi.h"
  55 #include <scsi/scsi_dbg.h>
  56 #include <scsi/scsi_host.h>
  57 #include <scsi/scsi_driver.h>
  58 #include <scsi/scsi_ioctl.h>
  59 #include <scsi/sg.h>
  60
  61 #include "scsi_logging.h"
  62
  63 #ifdef CONFIG_SCSI_PROC_FS
  64 #include <linux/proc_fs.h>
  65 static char *sg_version_date = "20061027";
  66
  67 static int sg_proc_init(void);
  68 static void sg_proc_cleanup(void);
  69 #endif
  70
  71 #define SG_ALLOW_DIO_DEF 0
  72
  73 #define SG_MAX_DEVS 32768
  74
  75 /*
  76  * Suppose you want to calculate the formula muldiv(x,m,d)=int(x * m / d)
  77  * Then when using 32 bit integers x * m may overflow during the calculation.
  78  * Replacing muldiv(x) by muldiv(x)=((x % d) * m) / d + int(x / d) * m
  79  * calculates the same, but prevents the overflow when both m and d
  80  * are "small" numbers (like HZ and USER_HZ).
  81  * Of course an overflow is inavoidable if the result of muldiv doesn't fit
  82  * in 32 bits.
  83  */
  84 #define MULDIV(X,MUL,DIV) ((((X % DIV) * MUL) / DIV) + ((X / DIV) * MUL))
  85
  86 #define SG_DEFAULT_TIMEOUT MULDIV(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
  87
  88 int sg_big_buff = SG_DEF_RESERVED_SIZE;
  89 /* N.B. This variable is readable and writeable via
  90    /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
  91    of this size (or less if there is not enough memory) will be reserved
  92    for use by this file descriptor. [Deprecated usage: this variable is also
  93    readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
  94    the kernel (i.e. it is not a module).] */
  95 static int def_reserved_size = -1;      /* picks up init parameter */
  96 static int sg_allow_dio = SG_ALLOW_DIO_DEF;
  97
  98 static int scatter_elem_sz = SG_SCATTER_SZ;
  99 static int scatter_elem_sz_prev = SG_SCATTER_SZ;
 100
 101 #define SG_SECTOR_SZ 512
 102
 103 static int sg_add(struct device *, struct class_interface *);
 104 static void sg_remove(struct device *, struct class_interface *);
 105
 106 static DEFINE_IDR(sg_index_idr);
 107 static DEFINE_RWLOCK(sg_index_lock);    /* Also used to lock
 108                                                            file descriptor list for device */
 109
 110 static struct class_interface sg_interface = {
 111         .add_dev        = sg_add,
 112         .remove_dev     = sg_remove,
 113 };
 114
 115 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
 116         unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
 117         unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */
 118         unsigned bufflen;       /* Size of (aggregate) data buffer */
 119         struct page **pages;
 120         int page_order;
 121         char dio_in_use;        /* 0->indirect IO (or mmap), 1->dio */
 122         unsigned char cmd_opcode; /* first byte of command */
 123 } Sg_scatter_hold;
 124
 125 struct sg_device;               /* forward declarations */
 126 struct sg_fd;
 127
 128 typedef struct sg_request {     /* SG_MAX_QUEUE requests outstanding per file */
 129         struct sg_request *nextrp;      /* NULL -> tail request (slist) */
 130         struct sg_fd *parentfp; /* NULL -> not in use */
 131         Sg_scatter_hold data;   /* hold buffer, perhaps scatter list */
 132         sg_io_hdr_t header;     /* scsi command+info, see <scsi/sg.h> */
 133         unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
 134         char res_used;          /* 1 -> using reserve buffer, 0 -> not ... */
 135         char orphan;            /* 1 -> drop on sight, 0 -> normal */
 136         char sg_io_owned;       /* 1 -> packet belongs to SG_IO */
 137         volatile char done;     /* 0->before bh, 1->before read, 2->read */
 138         struct request *rq;
 139         struct bio *bio;
 140         struct execute_work ew;
 141 } Sg_request;
 142
 143 typedef struct sg_fd {          /* holds the state of a file descriptor */
 144         struct list_head sfd_siblings;
 145         struct sg_device *parentdp;     /* owning device */
 146         wait_queue_head_t read_wait;    /* queue read until command done */
 147         rwlock_t rq_list_lock;  /* protect access to list in req_arr */
 148         int timeout;            /* defaults to SG_DEFAULT_TIMEOUT      */
 149         int timeout_user;       /* defaults to SG_DEFAULT_TIMEOUT_USER */
 150         Sg_scatter_hold reserve;        /* buffer held for this file descriptor */
 151         unsigned save_scat_len; /* original length of trunc. scat. element */
 152         Sg_request *headrp;     /* head of request slist, NULL->empty */
 153         struct fasync_struct *async_qp; /* used by asynchronous notification */
 154         Sg_request req_arr[SG_MAX_QUEUE];       /* used as singly-linked list */
 155         char low_dma;           /* as in parent but possibly overridden to 1 */
 156         char force_packid;      /* 1 -> pack_id input to read(), 0 -> ignored */
 157         volatile char closed;   /* 1 -> fd closed but request(s) outstanding */
 158         char cmd_q;             /* 1 -> allow command queuing, 0 -> don't */
 159         char next_cmd_len;      /* 0 -> automatic (def), >0 -> use on next write() */
 160         char keep_orphan;       /* 0 -> drop orphan (def), 1 -> keep for read() */
 161         char mmap_called;       /* 0 -> mmap() never called on this fd */
 162         struct kref f_ref;
 163         struct execute_work ew;
 164 } Sg_fd;
 165
 166 typedef struct sg_device { /* holds the state of each scsi generic device */
 167         struct scsi_device *device;
 168         wait_queue_head_t o_excl_wait;  /* queue open() when O_EXCL in use */
 169         int sg_tablesize;       /* adapter's max scatter-gather table size */
 170         u32 index;              /* device index number */
 171         struct list_head sfds;
 172         volatile char detached; /* 0->attached, 1->detached pending removal */
 173         volatile char exclude;  /* opened for exclusive access */
 174         char sgdebug;           /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
 175         struct gendisk *disk;
 176         struct cdev * cdev;     /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
 177         struct kref d_ref;
 178 } Sg_device;
 179
 180 /* tasklet or soft irq callback */
 181 static void sg_rq_end_io(struct request *rq, int uptodate);
 182 static int sg_start_req(Sg_request *srp, unsigned char *cmd);
 183 static int sg_finish_rem_req(Sg_request * srp);
 184 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
 185 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
 186                            Sg_request * srp);
 187 static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
 188                         const char __user *buf, size_t count, int blocking,
 189                         int read_only, int sg_io_owned, Sg_request **o_srp);
 190 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
 191                            unsigned char *cmnd, int timeout, int blocking);
 192 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
 193 static void sg_remove_scat(Sg_scatter_hold * schp);
 194 static void sg_build_reserve(Sg_fd * sfp, int req_size);
 195 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
 196 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
 197 static Sg_fd *sg_add_sfp(Sg_device * sdp, int dev);
 198 static void sg_remove_sfp(struct kref *);
 199 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
 200 static Sg_request *sg_add_request(Sg_fd * sfp);
 201 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
 202 static int sg_res_in_use(Sg_fd * sfp);
 203 static Sg_device *sg_get_dev(int dev);
 204 static void sg_put_dev(Sg_device *sdp);
 205
 206 #define SZ_SG_HEADER sizeof(struct sg_header)
 207 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
 208 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
 209 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
 210
 211 static int sg_allow_access(struct file *filp, unsigned char *cmd)
 212 {
 213         struct sg_fd *sfp = (struct sg_fd *)filp->private_data;
 214
 215         if (sfp->parentdp->device->type == TYPE_SCANNER)
 216                 return 0;
 217
 218         return blk_verify_command(cmd, filp->f_mode & FMODE_WRITE);
 219 }
 220
 221 static int
 222 sg_open(struct inode *inode, struct file *filp)
 223 {
 224         int dev = iminor(inode);
 225         int flags = filp->f_flags;
 226         struct request_queue *q;
 227         Sg_device *sdp;
 228         Sg_fd *sfp;
 229         int res;
 230         int retval;
 231
 232         lock_kernel();
 233         nonseekable_open(inode, filp);
 234         SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags));
 235         sdp = sg_get_dev(dev);
 236         if (IS_ERR(sdp)) {
 237                 retval = PTR_ERR(sdp);
 238                 sdp = NULL;
 239                 goto sg_put;
 240         }
 241
 242         /* This driver's module count bumped by fops_get in <linux/fs.h> */
 243         /* Prevent the device driver from vanishing while we sleep */
 244         retval = scsi_device_get(sdp->device);
 245         if (retval)
 246                 goto sg_put;
 247
 248         if (!((flags & O_NONBLOCK) ||
 249               scsi_block_when_processing_errors(sdp->device))) {
 250                 retval = -ENXIO;
 251                 /* we are in error recovery for this device */
 252                 goto error_out;
 253         }
 254
 255         if (flags & O_EXCL) {
 256                 if (O_RDONLY == (flags & O_ACCMODE)) {
 257                         retval = -EPERM; /* Can't lock it with read only access */
 258                         goto error_out;
 259                 }
 260                 if (!list_empty(&sdp->sfds) && (flags & O_NONBLOCK)) {
 261                         retval = -EBUSY;
 262                         goto error_out;
 263                 }
 264                 res = 0;
 265                 __wait_event_interruptible(sdp->o_excl_wait,
 266                                            ((!list_empty(&sdp->sfds) || sdp->exclude) ? 0 : (sdp->exclude = 1)), res);
 267                 if (res) {
 268                         retval = res;   /* -ERESTARTSYS because signal hit process */
 269                         goto error_out;
 270                 }
 271         } else if (sdp->exclude) {      /* some other fd has an exclusive lock on dev */
 272                 if (flags & O_NONBLOCK) {
 273                         retval = -EBUSY;
 274                         goto error_out;
 275                 }
 276                 res = 0;
 277                 __wait_event_interruptible(sdp->o_excl_wait, (!sdp->exclude),
 278                                            res);
 279                 if (res) {
 280                         retval = res;   /* -ERESTARTSYS because signal hit process */
 281                         goto error_out;
 282                 }
 283         }
 284         if (sdp->detached) {
 285                 retval = -ENODEV;
 286                 goto error_out;
 287         }
 288         if (list_empty(&sdp->sfds)) {   /* no existing opens on this device */
 289                 sdp->sgdebug = 0;
 290                 q = sdp->device->request_queue;
 291                 sdp->sg_tablesize = queue_max_segments(q);
 292         }
 293         if ((sfp = sg_add_sfp(sdp, dev)))
 294                 filp->private_data = sfp;
 295         else {
 296                 if (flags & O_EXCL) {
 297                         sdp->exclude = 0;       /* undo if error */
 298                         wake_up_interruptible(&sdp->o_excl_wait);
 299                 }
 300                 retval = -ENOMEM;
 301                 goto error_out;
 302         }
 303         retval = 0;
 304 error_out:
 305         if (retval)
 306                 scsi_device_put(sdp->device);
 307 sg_put:
 308         if (sdp)
 309                 sg_put_dev(sdp);
 310         unlock_kernel();
 311         return retval;
 312 }
 313
 314 /* Following function was formerly called 'sg_close' */
 315 static int
 316 sg_release(struct inode *inode, struct file *filp)
 317 {
 318         Sg_device *sdp;
 319         Sg_fd *sfp;
 320
 321         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 322                 return -ENXIO;
 323         SCSI_LOG_TIMEOUT(3, printk("sg_release: %s\n", sdp->disk->disk_name));
 324
 325         sfp->closed = 1;
 326
 327         sdp->exclude = 0;
 328         wake_up_interruptible(&sdp->o_excl_wait);
 329
 330         kref_put(&sfp->f_ref, sg_remove_sfp);
 331         return 0;
 332 }
 333
 334 static ssize_t
 335 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
 336 {
 337         Sg_device *sdp;
 338         Sg_fd *sfp;
 339         Sg_request *srp;
 340         int req_pack_id = -1;
 341         sg_io_hdr_t *hp;
 342         struct sg_header *old_hdr = NULL;
 343         int retval = 0;
 344
 345         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 346                 return -ENXIO;
 347         SCSI_LOG_TIMEOUT(3, printk("sg_read: %s, count=%d\n",
 348                                    sdp->disk->disk_name, (int) count));
 349
 350         if (!access_ok(VERIFY_WRITE, buf, count))
 351                 return -EFAULT;
 352         if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
 353                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 354                 if (!old_hdr)
 355                         return -ENOMEM;
 356                 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
 357                         retval = -EFAULT;
 358                         goto free_old_hdr;
 359                 }
 360                 if (old_hdr->reply_len < 0) {
 361                         if (count >= SZ_SG_IO_HDR) {
 362                                 sg_io_hdr_t *new_hdr;
 363                                 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
 364                                 if (!new_hdr) {
 365                                         retval = -ENOMEM;
 366                                         goto free_old_hdr;
 367                                 }
 368                                 retval =__copy_from_user
 369                                     (new_hdr, buf, SZ_SG_IO_HDR);
 370                                 req_pack_id = new_hdr->pack_id;
 371                                 kfree(new_hdr);
 372                                 if (retval) {
 373                                         retval = -EFAULT;
 374                                         goto free_old_hdr;
 375                                 }
 376                         }
 377                 } else
 378                         req_pack_id = old_hdr->pack_id;
 379         }
 380         srp = sg_get_rq_mark(sfp, req_pack_id);
 381         if (!srp) {             /* now wait on packet to arrive */
 382                 if (sdp->detached) {
 383                         retval = -ENODEV;
 384                         goto free_old_hdr;
 385                 }
 386                 if (filp->f_flags & O_NONBLOCK) {
 387                         retval = -EAGAIN;
 388                         goto free_old_hdr;
 389                 }
 390                 while (1) {
 391                         retval = 0; /* following macro beats race condition */
 392                         __wait_event_interruptible(sfp->read_wait,
 393                                 (sdp->detached ||
 394                                 (srp = sg_get_rq_mark(sfp, req_pack_id))),
 395                                 retval);
 396                         if (sdp->detached) {
 397                                 retval = -ENODEV;
 398                                 goto free_old_hdr;
 399                         }
 400                         if (0 == retval)
 401                                 break;
 402
 403                         /* -ERESTARTSYS as signal hit process */
 404                         goto free_old_hdr;
 405                 }
 406         }
 407         if (srp->header.interface_id != '\0') {
 408                 retval = sg_new_read(sfp, buf, count, srp);
 409                 goto free_old_hdr;
 410         }
 411
 412         hp = &srp->header;
 413         if (old_hdr == NULL) {
 414                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 415                 if (! old_hdr) {
 416                         retval = -ENOMEM;
 417                         goto free_old_hdr;
 418                 }
 419         }
 420         memset(old_hdr, 0, SZ_SG_HEADER);
 421         old_hdr->reply_len = (int) hp->timeout;
 422         old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
 423         old_hdr->pack_id = hp->pack_id;
 424         old_hdr->twelve_byte =
 425             ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
 426         old_hdr->target_status = hp->masked_status;
 427         old_hdr->host_status = hp->host_status;
 428         old_hdr->driver_status = hp->driver_status;
 429         if ((CHECK_CONDITION & hp->masked_status) ||
 430             (DRIVER_SENSE & hp->driver_status))
 431                 memcpy(old_hdr->sense_buffer, srp->sense_b,
 432                        sizeof (old_hdr->sense_buffer));
 433         switch (hp->host_status) {
 434         /* This setup of 'result' is for backward compatibility and is best
 435            ignored by the user who should use target, host + driver status */
 436         case DID_OK:
 437         case DID_PASSTHROUGH:
 438         case DID_SOFT_ERROR:
 439                 old_hdr->result = 0;
 440                 break;
 441         case DID_NO_CONNECT:
 442         case DID_BUS_BUSY:
 443         case DID_TIME_OUT:
 444                 old_hdr->result = EBUSY;
 445                 break;
 446         case DID_BAD_TARGET:
 447         case DID_ABORT:
 448         case DID_PARITY:
 449         case DID_RESET:
 450         case DID_BAD_INTR:
 451                 old_hdr->result = EIO;
 452                 break;
 453         case DID_ERROR:
 454                 old_hdr->result = (srp->sense_b[0] == 0 &&
 455                                   hp->masked_status == GOOD) ? 0 : EIO;
 456                 break;
 457         default:
 458                 old_hdr->result = EIO;
 459                 break;
 460         }
 461
 462         /* Now copy the result back to the user buffer.  */
 463         if (count >= SZ_SG_HEADER) {
 464                 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
 465                         retval = -EFAULT;
 466                         goto free_old_hdr;
 467                 }
 468                 buf += SZ_SG_HEADER;
 469                 if (count > old_hdr->reply_len)
 470                         count = old_hdr->reply_len;
 471                 if (count > SZ_SG_HEADER) {
 472                         if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
 473                                 retval = -EFAULT;
 474                                 goto free_old_hdr;
 475                         }
 476                 }
 477         } else
 478                 count = (old_hdr->result == 0) ? 0 : -EIO;
 479         sg_finish_rem_req(srp);
 480         retval = count;
 481 free_old_hdr:
 482         kfree(old_hdr);
 483         return retval;
 484 }
 485
 486 static ssize_t
 487 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
 488 {
 489         sg_io_hdr_t *hp = &srp->header;
 490         int err = 0;
 491         int len;
 492
 493         if (count < SZ_SG_IO_HDR) {
 494                 err = -EINVAL;
 495                 goto err_out;
 496         }
 497         hp->sb_len_wr = 0;
 498         if ((hp->mx_sb_len > 0) && hp->sbp) {
 499                 if ((CHECK_CONDITION & hp->masked_status) ||
 500                     (DRIVER_SENSE & hp->driver_status)) {
 501                         int sb_len = SCSI_SENSE_BUFFERSIZE;
 502                         sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
 503                         len = 8 + (int) srp->sense_b[7];        /* Additional sense length field */
 504                         len = (len > sb_len) ? sb_len : len;
 505                         if (copy_to_user(hp->sbp, srp->sense_b, len)) {
 506                                 err = -EFAULT;
 507                                 goto err_out;
 508                         }
 509                         hp->sb_len_wr = len;
 510                 }
 511         }
 512         if (hp->masked_status || hp->host_status || hp->driver_status)
 513                 hp->info |= SG_INFO_CHECK;
 514         if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
 515                 err = -EFAULT;
 516                 goto err_out;
 517         }
 518 err_out:
 519         err = sg_finish_rem_req(srp);
 520         return (0 == err) ? count : err;
 521 }
 522
 523 static ssize_t
 524 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
 525 {
 526         int mxsize, cmd_size, k;
 527         int input_size, blocking;
 528         unsigned char opcode;
 529         Sg_device *sdp;
 530         Sg_fd *sfp;
 531         Sg_request *srp;
 532         struct sg_header old_hdr;
 533         sg_io_hdr_t *hp;
 534         unsigned char cmnd[MAX_COMMAND_SIZE];
 535
 536         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 537                 return -ENXIO;
 538         SCSI_LOG_TIMEOUT(3, printk("sg_write: %s, count=%d\n",
 539                                    sdp->disk->disk_name, (int) count));
 540         if (sdp->detached)
 541                 return -ENODEV;
 542         if (!((filp->f_flags & O_NONBLOCK) ||
 543               scsi_block_when_processing_errors(sdp->device)))
 544                 return -ENXIO;
 545
 546         if (!access_ok(VERIFY_READ, buf, count))
 547                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 548         if (count < SZ_SG_HEADER)
 549                 return -EIO;
 550         if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
 551                 return -EFAULT;
 552         blocking = !(filp->f_flags & O_NONBLOCK);
 553         if (old_hdr.reply_len < 0)
 554                 return sg_new_write(sfp, filp, buf, count,
 555                                     blocking, 0, 0, NULL);
 556         if (count < (SZ_SG_HEADER + 6))
 557                 return -EIO;    /* The minimum scsi command length is 6 bytes. */
 558
 559         if (!(srp = sg_add_request(sfp))) {
 560                 SCSI_LOG_TIMEOUT(1, printk("sg_write: queue full\n"));
 561                 return -EDOM;
 562         }
 563         buf += SZ_SG_HEADER;
 564         __get_user(opcode, buf);
 565         if (sfp->next_cmd_len > 0) {
 566                 if (sfp->next_cmd_len > MAX_COMMAND_SIZE) {
 567                         SCSI_LOG_TIMEOUT(1, printk("sg_write: command length too long\n"));
 568                         sfp->next_cmd_len = 0;
 569                         sg_remove_request(sfp, srp);
 570                         return -EIO;
 571                 }
 572                 cmd_size = sfp->next_cmd_len;
 573                 sfp->next_cmd_len = 0;  /* reset so only this write() effected */
 574         } else {
 575                 cmd_size = COMMAND_SIZE(opcode);        /* based on SCSI command group */
 576                 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
 577                         cmd_size = 12;
 578         }
 579         SCSI_LOG_TIMEOUT(4, printk(
 580                 "sg_write:   scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
 581 /* Determine buffer size.  */
 582         input_size = count - cmd_size;
 583         mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
 584         mxsize -= SZ_SG_HEADER;
 585         input_size -= SZ_SG_HEADER;
 586         if (input_size < 0) {
 587                 sg_remove_request(sfp, srp);
 588                 return -EIO;    /* User did not pass enough bytes for this command. */
 589         }
 590         hp = &srp->header;
 591         hp->interface_id = '\0';        /* indicator of old interface tunnelled */
 592         hp->cmd_len = (unsigned char) cmd_size;
 593         hp->iovec_count = 0;
 594         hp->mx_sb_len = 0;
 595         if (input_size > 0)
 596                 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
 597                     SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
 598         else
 599                 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
 600         hp->dxfer_len = mxsize;
 601         if (hp->dxfer_direction == SG_DXFER_TO_DEV)
 602                 hp->dxferp = (char __user *)buf + cmd_size;
 603         else
 604                 hp->dxferp = NULL;
 605         hp->sbp = NULL;
 606         hp->timeout = old_hdr.reply_len;        /* structure abuse ... */
 607         hp->flags = input_size; /* structure abuse ... */
 608         hp->pack_id = old_hdr.pack_id;
 609         hp->usr_ptr = NULL;
 610         if (__copy_from_user(cmnd, buf, cmd_size))
 611                 return -EFAULT;
 612         /*
 613          * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
 614          * but is is possible that the app intended SG_DXFER_TO_DEV, because there
 615          * is a non-zero input_size, so emit a warning.
 616          */
 617         if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
 618                 static char cmd[TASK_COMM_LEN];
 619                 if (strcmp(current->comm, cmd) && printk_ratelimit()) {
 620                         printk(KERN_WARNING
 621                                "sg_write: data in/out %d/%d bytes for SCSI command 0x%x--"
 622                                "guessing data in;\n   "
 623                                "program %s not setting count and/or reply_len properly\n",
 624                                old_hdr.reply_len - (int)SZ_SG_HEADER,
 625                                input_size, (unsigned int) cmnd[0],
 626                                current->comm);
 627                         strcpy(cmd, current->comm);
 628                 }
 629         }
 630         k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
 631         return (k < 0) ? k : count;
 632 }
 633
 634 static ssize_t
 635 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
 636                  size_t count, int blocking, int read_only, int sg_io_owned,
 637                  Sg_request **o_srp)
 638 {
 639         int k;
 640         Sg_request *srp;
 641         sg_io_hdr_t *hp;
 642         unsigned char cmnd[MAX_COMMAND_SIZE];
 643         int timeout;
 644         unsigned long ul_timeout;
 645
 646         if (count < SZ_SG_IO_HDR)
 647                 return -EINVAL;
 648         if (!access_ok(VERIFY_READ, buf, count))
 649                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 650
 651         sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
 652         if (!(srp = sg_add_request(sfp))) {
 653                 SCSI_LOG_TIMEOUT(1, printk("sg_new_write: queue full\n"));
 654                 return -EDOM;
 655         }
 656         srp->sg_io_owned = sg_io_owned;
 657         hp = &srp->header;
 658         if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
 659                 sg_remove_request(sfp, srp);
 660                 return -EFAULT;
 661         }
 662         if (hp->interface_id != 'S') {
 663                 sg_remove_request(sfp, srp);
 664                 return -ENOSYS;
 665         }
 666         if (hp->flags & SG_FLAG_MMAP_IO) {
 667                 if (hp->dxfer_len > sfp->reserve.bufflen) {
 668                         sg_remove_request(sfp, srp);
 669                         return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
 670                 }
 671                 if (hp->flags & SG_FLAG_DIRECT_IO) {
 672                         sg_remove_request(sfp, srp);
 673                         return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
 674                 }
 675                 if (sg_res_in_use(sfp)) {
 676                         sg_remove_request(sfp, srp);
 677                         return -EBUSY;  /* reserve buffer already being used */
 678                 }
 679         }
 680         ul_timeout = msecs_to_jiffies(srp->header.timeout);
 681         timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
 682         if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
 683                 sg_remove_request(sfp, srp);
 684                 return -EMSGSIZE;
 685         }
 686         if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
 687                 sg_remove_request(sfp, srp);
 688                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 689         }
 690         if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
 691                 sg_remove_request(sfp, srp);
 692                 return -EFAULT;
 693         }
 694         if (read_only && sg_allow_access(file, cmnd)) {
 695                 sg_remove_request(sfp, srp);
 696                 return -EPERM;
 697         }
 698         k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
 699         if (k < 0)
 700                 return k;
 701         if (o_srp)
 702                 *o_srp = srp;
 703         return count;
 704 }
 705
 706 static int
 707 sg_common_write(Sg_fd * sfp, Sg_request * srp,
 708                 unsigned char *cmnd, int timeout, int blocking)
 709 {
 710         int k, data_dir;
 711         Sg_device *sdp = sfp->parentdp;
 712         sg_io_hdr_t *hp = &srp->header;
 713
 714         srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
 715         hp->status = 0;
 716         hp->masked_status = 0;
 717         hp->msg_status = 0;
 718         hp->info = 0;
 719         hp->host_status = 0;
 720         hp->driver_status = 0;
 721         hp->resid = 0;
 722         SCSI_LOG_TIMEOUT(4, printk("sg_common_write:  scsi opcode=0x%02x, cmd_size=%d\n",
 723                           (int) cmnd[0], (int) hp->cmd_len));
 724
 725         k = sg_start_req(srp, cmnd);
 726         if (k) {
 727                 SCSI_LOG_TIMEOUT(1, printk("sg_common_write: start_req err=%d\n", k));
 728                 sg_finish_rem_req(srp);
 729                 return k;       /* probably out of space --> ENOMEM */
 730         }
 731         if (sdp->detached) {
 732                 if (srp->bio)
 733                         blk_end_request_all(srp->rq, -EIO);
 734                 sg_finish_rem_req(srp);
 735                 return -ENODEV;
 736         }
 737
 738         switch (hp->dxfer_direction) {
 739         case SG_DXFER_TO_FROM_DEV:
 740         case SG_DXFER_FROM_DEV:
 741                 data_dir = DMA_FROM_DEVICE;
 742                 break;
 743         case SG_DXFER_TO_DEV:
 744                 data_dir = DMA_TO_DEVICE;
 745                 break;
 746         case SG_DXFER_UNKNOWN:
 747                 data_dir = DMA_BIDIRECTIONAL;
 748                 break;
 749         default:
 750                 data_dir = DMA_NONE;
 751                 break;
 752         }
 753         hp->duration = jiffies_to_msecs(jiffies);
 754
 755         srp->rq->timeout = timeout;
 756         kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
 757         blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk,
 758                               srp->rq, 1, sg_rq_end_io);
 759         return 0;
 760 }
 761
 762 static int
 763 sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
 764 {
 765         void __user *p = (void __user *)arg;
 766         int __user *ip = p;
 767         int result, val, read_only;
 768         Sg_device *sdp;
 769         Sg_fd *sfp;
 770         Sg_request *srp;
 771         unsigned long iflags;
 772
 773         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 774                 return -ENXIO;
 775
 776         SCSI_LOG_TIMEOUT(3, printk("sg_ioctl: %s, cmd=0x%x\n",
 777                                    sdp->disk->disk_name, (int) cmd_in));
 778         read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
 779
 780         switch (cmd_in) {
 781         case SG_IO:
 782                 {
 783                         int blocking = 1;       /* ignore O_NONBLOCK flag */
 784
 785                         if (sdp->detached)
 786                                 return -ENODEV;
 787                         if (!scsi_block_when_processing_errors(sdp->device))
 788                                 return -ENXIO;
 789                         if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
 790                                 return -EFAULT;
 791                         result =
 792                             sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
 793                                          blocking, read_only, 1, &srp);
 794                         if (result < 0)
 795                                 return result;
 796                         while (1) {
 797                                 result = 0;     /* following macro to beat race condition */
 798                                 __wait_event_interruptible(sfp->read_wait,
 799                                         (srp->done || sdp->detached),
 800                                         result);
 801                                 if (sdp->detached)
 802                                         return -ENODEV;
 803                                 write_lock_irq(&sfp->rq_list_lock);
 804                                 if (srp->done) {
 805                                         srp->done = 2;
 806                                         write_unlock_irq(&sfp->rq_list_lock);
 807                                         break;
 808                                 }
 809                                 srp->orphan = 1;
 810                                 write_unlock_irq(&sfp->rq_list_lock);
 811                                 return result;  /* -ERESTARTSYS because signal hit process */
 812                         }
 813                         result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
 814                         return (result < 0) ? result : 0;
 815                 }
 816         case SG_SET_TIMEOUT:
 817                 result = get_user(val, ip);
 818                 if (result)
 819                         return result;
 820                 if (val < 0)
 821                         return -EIO;
 822                 if (val >= MULDIV (INT_MAX, USER_HZ, HZ))
 823                     val = MULDIV (INT_MAX, USER_HZ, HZ);
 824                 sfp->timeout_user = val;
 825                 sfp->timeout = MULDIV (val, HZ, USER_HZ);
 826
 827                 return 0;
 828         case SG_GET_TIMEOUT:    /* N.B. User receives timeout as return value */
 829                                 /* strange ..., for backward compatibility */
 830                 return sfp->timeout_user;
 831         case SG_SET_FORCE_LOW_DMA:
 832                 result = get_user(val, ip);
 833                 if (result)
 834                         return result;
 835                 if (val) {
 836                         sfp->low_dma = 1;
 837                         if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
 838                                 val = (int) sfp->reserve.bufflen;
 839                                 sg_remove_scat(&sfp->reserve);
 840                                 sg_build_reserve(sfp, val);
 841                         }
 842                 } else {
 843                         if (sdp->detached)
 844                                 return -ENODEV;
 845                         sfp->low_dma = sdp->device->host->unchecked_isa_dma;
 846                 }
 847                 return 0;
 848         case SG_GET_LOW_DMA:
 849                 return put_user((int) sfp->low_dma, ip);
 850         case SG_GET_SCSI_ID:
 851                 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
 852                         return -EFAULT;
 853                 else {
 854                         sg_scsi_id_t __user *sg_idp = p;
 855
 856                         if (sdp->detached)
 857                                 return -ENODEV;
 858                         __put_user((int) sdp->device->host->host_no,
 859                                    &sg_idp->host_no);
 860                         __put_user((int) sdp->device->channel,
 861                                    &sg_idp->channel);
 862                         __put_user((int) sdp->device->id, &sg_idp->scsi_id);
 863                         __put_user((int) sdp->device->lun, &sg_idp->lun);
 864                         __put_user((int) sdp->device->type, &sg_idp->scsi_type);
 865                         __put_user((short) sdp->device->host->cmd_per_lun,
 866                                    &sg_idp->h_cmd_per_lun);
 867                         __put_user((short) sdp->device->queue_depth,
 868                                    &sg_idp->d_queue_depth);
 869                         __put_user(0, &sg_idp->unused[0]);
 870                         __put_user(0, &sg_idp->unused[1]);
 871                         return 0;
 872                 }
 873         case SG_SET_FORCE_PACK_ID:
 874                 result = get_user(val, ip);
 875                 if (result)
 876                         return result;
 877                 sfp->force_packid = val ? 1 : 0;
 878                 return 0;
 879         case SG_GET_PACK_ID:
 880                 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
 881                         return -EFAULT;
 882                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 883                 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
 884                         if ((1 == srp->done) && (!srp->sg_io_owned)) {
 885                                 read_unlock_irqrestore(&sfp->rq_list_lock,
 886                                                        iflags);
 887                                 __put_user(srp->header.pack_id, ip);
 888                                 return 0;
 889                         }
 890                 }
 891                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 892                 __put_user(-1, ip);
 893                 return 0;
 894         case SG_GET_NUM_WAITING:
 895                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 896                 for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) {
 897                         if ((1 == srp->done) && (!srp->sg_io_owned))
 898                                 ++val;
 899                 }
 900                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 901                 return put_user(val, ip);
 902         case SG_GET_SG_TABLESIZE:
 903                 return put_user(sdp->sg_tablesize, ip);
 904         case SG_SET_RESERVED_SIZE:
 905                 result = get_user(val, ip);
 906                 if (result)
 907                         return result;
 908                 if (val < 0)
 909                         return -EINVAL;
 910                 val = min_t(int, val,
 911                             queue_max_sectors(sdp->device->request_queue) * 512);
 912                 if (val != sfp->reserve.bufflen) {
 913                         if (sg_res_in_use(sfp) || sfp->mmap_called)
 914                                 return -EBUSY;
 915                         sg_remove_scat(&sfp->reserve);
 916                         sg_build_reserve(sfp, val);
 917                 }
 918                 return 0;
 919         case SG_GET_RESERVED_SIZE:
 920                 val = min_t(int, sfp->reserve.bufflen,
 921                             queue_max_sectors(sdp->device->request_queue) * 512);
 922                 return put_user(val, ip);
 923         case SG_SET_COMMAND_Q:
 924                 result = get_user(val, ip);
 925                 if (result)
 926                         return result;
 927                 sfp->cmd_q = val ? 1 : 0;
 928                 return 0;
 929         case SG_GET_COMMAND_Q:
 930                 return put_user((int) sfp->cmd_q, ip);
 931         case SG_SET_KEEP_ORPHAN:
 932                 result = get_user(val, ip);
 933                 if (result)
 934                         return result;
 935                 sfp->keep_orphan = val;
 936                 return 0;
 937         case SG_GET_KEEP_ORPHAN:
 938                 return put_user((int) sfp->keep_orphan, ip);
 939         case SG_NEXT_CMD_LEN:
 940                 result = get_user(val, ip);
 941                 if (result)
 942                         return result;
 943                 sfp->next_cmd_len = (val > 0) ? val : 0;
 944                 return 0;
 945         case SG_GET_VERSION_NUM:
 946                 return put_user(sg_version_num, ip);
 947         case SG_GET_ACCESS_COUNT:
 948                 /* faked - we don't have a real access count anymore */
 949                 val = (sdp->device ? 1 : 0);
 950                 return put_user(val, ip);
 951         case SG_GET_REQUEST_TABLE:
 952                 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
 953                         return -EFAULT;
 954                 else {
 955                         sg_req_info_t *rinfo;
 956                         unsigned int ms;
 957
 958                         rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
 959                                                                 GFP_KERNEL);
 960                         if (!rinfo)
 961                                 return -ENOMEM;
 962                         read_lock_irqsave(&sfp->rq_list_lock, iflags);
 963                         for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE;
 964                              ++val, srp = srp ? srp->nextrp : srp) {
 965                                 memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
 966                                 if (srp) {
 967                                         rinfo[val].req_state = srp->done + 1;
 968                                         rinfo[val].problem =
 969                                             srp->header.masked_status &
 970                                             srp->header.host_status &
 971                                             srp->header.driver_status;
 972                                         if (srp->done)
 973                                                 rinfo[val].duration =
 974                                                         srp->header.duration;
 975                                         else {
 976                                                 ms = jiffies_to_msecs(jiffies);
 977                                                 rinfo[val].duration =
 978                                                     (ms > srp->header.duration) ?
 979                                                     (ms - srp->header.duration) : 0;
 980                                         }
 981                                         rinfo[val].orphan = srp->orphan;
 982                                         rinfo[val].sg_io_owned =
 983                                                         srp->sg_io_owned;
 984                                         rinfo[val].pack_id =
 985                                                         srp->header.pack_id;
 986                                         rinfo[val].usr_ptr =
 987                                                         srp->header.usr_ptr;
 988                                 }
 989                         }
 990                         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 991                         result = __copy_to_user(p, rinfo,
 992                                                 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
 993                         result = result ? -EFAULT : 0;
 994                         kfree(rinfo);
 995                         return result;
 996                 }
 997         case SG_EMULATED_HOST:
 998                 if (sdp->detached)
 999                         return -ENODEV;
1000                 return put_user(sdp->device->host->hostt->emulated, ip);
1001         case SG_SCSI_RESET:
1002                 if (sdp->detached)
1003                         return -ENODEV;
1004                 if (filp->f_flags & O_NONBLOCK) {
1005                         if (scsi_host_in_recovery(sdp->device->host))
1006                                 return -EBUSY;
1007                 } else if (!scsi_block_when_processing_errors(sdp->device))
1008                         return -EBUSY;
1009                 result = get_user(val, ip);
1010                 if (result)
1011                         return result;
1012                 if (SG_SCSI_RESET_NOTHING == val)
1013                         return 0;
1014                 switch (val) {
1015                 case SG_SCSI_RESET_DEVICE:
1016                         val = SCSI_TRY_RESET_DEVICE;
1017                         break;
1018                 case SG_SCSI_RESET_TARGET:
1019                         val = SCSI_TRY_RESET_TARGET;
1020                         break;
1021                 case SG_SCSI_RESET_BUS:
1022                         val = SCSI_TRY_RESET_BUS;
1023                         break;
1024                 case SG_SCSI_RESET_HOST:
1025                         val = SCSI_TRY_RESET_HOST;
1026                         break;
1027                 default:
1028                         return -EINVAL;
1029                 }
1030                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1031                         return -EACCES;
1032                 return (scsi_reset_provider(sdp->device, val) ==
1033                         SUCCESS) ? 0 : -EIO;
1034         case SCSI_IOCTL_SEND_COMMAND:
1035                 if (sdp->detached)
1036                         return -ENODEV;
1037                 if (read_only) {
1038                         unsigned char opcode = WRITE_6;
1039                         Scsi_Ioctl_Command __user *siocp = p;
1040
1041                         if (copy_from_user(&opcode, siocp->data, 1))
1042                                 return -EFAULT;
1043                         if (sg_allow_access(filp, &opcode))
1044                                 return -EPERM;
1045                 }
1046                 return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p);
1047         case SG_SET_DEBUG:
1048                 result = get_user(val, ip);
1049                 if (result)
1050                         return result;
1051                 sdp->sgdebug = (char) val;
1052                 return 0;
1053         case SCSI_IOCTL_GET_IDLUN:
1054         case SCSI_IOCTL_GET_BUS_NUMBER:
1055         case SCSI_IOCTL_PROBE_HOST:
1056         case SG_GET_TRANSFORM:
1057                 if (sdp->detached)
1058                         return -ENODEV;
1059                 return scsi_ioctl(sdp->device, cmd_in, p);
1060         case BLKSECTGET:
1061                 return put_user(queue_max_sectors(sdp->device->request_queue) * 512,
1062                                 ip);
1063         case BLKTRACESETUP:
1064                 return blk_trace_setup(sdp->device->request_queue,
1065                                        sdp->disk->disk_name,
1066                                        MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1067                                        NULL,
1068                                        (char *)arg);
1069         case BLKTRACESTART:
1070                 return blk_trace_startstop(sdp->device->request_queue, 1);
1071         case BLKTRACESTOP:
1072                 return blk_trace_startstop(sdp->device->request_queue, 0);
1073         case BLKTRACETEARDOWN:
1074                 return blk_trace_remove(sdp->device->request_queue);
1075         default:
1076                 if (read_only)
1077                         return -EPERM;  /* don't know so take safe approach */
1078                 return scsi_ioctl(sdp->device, cmd_in, p);
1079         }
1080 }
1081
1082 static long
1083 sg_unlocked_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1084 {
1085         int ret;
1086
1087         lock_kernel();
1088         ret = sg_ioctl(filp, cmd_in, arg);
1089         unlock_kernel();
1090
1091         return ret;
1092 }
1093
1094 #ifdef CONFIG_COMPAT
1095 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1096 {
1097         Sg_device *sdp;
1098         Sg_fd *sfp;
1099         struct scsi_device *sdev;
1100
1101         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1102                 return -ENXIO;
1103
1104         sdev = sdp->device;
1105         if (sdev->host->hostt->compat_ioctl) {
1106                 int ret;
1107
1108                 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1109
1110                 return ret;
1111         }
1112
1113         return -ENOIOCTLCMD;
1114 }
1115 #endif
1116
1117 static unsigned int
1118 sg_poll(struct file *filp, poll_table * wait)
1119 {
1120         unsigned int res = 0;
1121         Sg_device *sdp;
1122         Sg_fd *sfp;
1123         Sg_request *srp;
1124         int count = 0;
1125         unsigned long iflags;
1126
1127         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))
1128             || sfp->closed)
1129                 return POLLERR;
1130         poll_wait(filp, &sfp->read_wait, wait);
1131         read_lock_irqsave(&sfp->rq_list_lock, iflags);
1132         for (srp = sfp->headrp; srp; srp = srp->nextrp) {
1133                 /* if any read waiting, flag it */
1134                 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1135                         res = POLLIN | POLLRDNORM;
1136                 ++count;
1137         }
1138         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1139
1140         if (sdp->detached)
1141                 res |= POLLHUP;
1142         else if (!sfp->cmd_q) {
1143                 if (0 == count)
1144                         res |= POLLOUT | POLLWRNORM;
1145         } else if (count < SG_MAX_QUEUE)
1146                 res |= POLLOUT | POLLWRNORM;
1147         SCSI_LOG_TIMEOUT(3, printk("sg_poll: %s, res=0x%x\n",
1148                                    sdp->disk->disk_name, (int) res));
1149         return res;
1150 }
1151
1152 static int
1153 sg_fasync(int fd, struct file *filp, int mode)
1154 {
1155         Sg_device *sdp;
1156         Sg_fd *sfp;
1157
1158         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1159                 return -ENXIO;
1160         SCSI_LOG_TIMEOUT(3, printk("sg_fasync: %s, mode=%d\n",
1161                                    sdp->disk->disk_name, mode));
1162
1163         return fasync_helper(fd, filp, mode, &sfp->async_qp);
1164 }
1165
1166 static int
1167 sg_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1168 {
1169         Sg_fd *sfp;
1170         unsigned long offset, len, sa;
1171         Sg_scatter_hold *rsv_schp;
1172         int k, length;
1173
1174         if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1175                 return VM_FAULT_SIGBUS;
1176         rsv_schp = &sfp->reserve;
1177         offset = vmf->pgoff << PAGE_SHIFT;
1178         if (offset >= rsv_schp->bufflen)
1179                 return VM_FAULT_SIGBUS;
1180         SCSI_LOG_TIMEOUT(3, printk("sg_vma_fault: offset=%lu, scatg=%d\n",
1181                                    offset, rsv_schp->k_use_sg));
1182         sa = vma->vm_start;
1183         length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1184         for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1185                 len = vma->vm_end - sa;
1186                 len = (len < length) ? len : length;
1187                 if (offset < len) {
1188                         struct page *page = nth_page(rsv_schp->pages[k],
1189                                                      offset >> PAGE_SHIFT);
1190                         get_page(page); /* increment page count */
1191                         vmf->page = page;
1192                         return 0; /* success */
1193                 }
1194                 sa += len;
1195                 offset -= len;
1196         }
1197
1198         return VM_FAULT_SIGBUS;
1199 }
1200
1201 static const struct vm_operations_struct sg_mmap_vm_ops = {
1202         .fault = sg_vma_fault,
1203 };
1204
1205 static int
1206 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1207 {
1208         Sg_fd *sfp;
1209         unsigned long req_sz, len, sa;
1210         Sg_scatter_hold *rsv_schp;
1211         int k, length;
1212
1213         if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1214                 return -ENXIO;
1215         req_sz = vma->vm_end - vma->vm_start;
1216         SCSI_LOG_TIMEOUT(3, printk("sg_mmap starting, vm_start=%p, len=%d\n",
1217                                    (void *) vma->vm_start, (int) req_sz));
1218         if (vma->vm_pgoff)
1219                 return -EINVAL; /* want no offset */
1220         rsv_schp = &sfp->reserve;
1221         if (req_sz > rsv_schp->bufflen)
1222                 return -ENOMEM; /* cannot map more than reserved buffer */
1223
1224         sa = vma->vm_start;
1225         length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1226         for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1227                 len = vma->vm_end - sa;
1228                 len = (len < length) ? len : length;
1229                 sa += len;
1230         }
1231
1232         sfp->mmap_called = 1;
1233         vma->vm_flags |= VM_RESERVED;
1234         vma->vm_private_data = sfp;
1235         vma->vm_ops = &sg_mmap_vm_ops;
1236         return 0;
1237 }
1238
1239 static void sg_rq_end_io_usercontext(struct work_struct *work)
1240 {
1241         struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1242         struct sg_fd *sfp = srp->parentfp;
1243
1244         sg_finish_rem_req(srp);
1245         kref_put(&sfp->f_ref, sg_remove_sfp);
1246 }
1247
1248 /*
1249  * This function is a "bottom half" handler that is called by the mid
1250  * level when a command is completed (or has failed).
1251  */
1252 static void sg_rq_end_io(struct request *rq, int uptodate)
1253 {
1254         struct sg_request *srp = rq->end_io_data;
1255         Sg_device *sdp;
1256         Sg_fd *sfp;
1257         unsigned long iflags;
1258         unsigned int ms;
1259         char *sense;
1260         int result, resid, done = 1;
1261
1262         if (WARN_ON(srp->done != 0))
1263                 return;
1264
1265         sfp = srp->parentfp;
1266         if (WARN_ON(sfp == NULL))
1267                 return;
1268
1269         sdp = sfp->parentdp;
1270         if (unlikely(sdp->detached))
1271                 printk(KERN_INFO "sg_rq_end_io: device detached\n");
1272
1273         sense = rq->sense;
1274         result = rq->errors;
1275         resid = rq->resid_len;
1276
1277         SCSI_LOG_TIMEOUT(4, printk("sg_cmd_done: %s, pack_id=%d, res=0x%x\n",
1278                 sdp->disk->disk_name, srp->header.pack_id, result));
1279         srp->header.resid = resid;
1280         ms = jiffies_to_msecs(jiffies);
1281         srp->header.duration = (ms > srp->header.duration) ?
1282                                 (ms - srp->header.duration) : 0;
1283         if (0 != result) {
1284                 struct scsi_sense_hdr sshdr;
1285
1286                 srp->header.status = 0xff & result;
1287                 srp->header.masked_status = status_byte(result);
1288                 srp->header.msg_status = msg_byte(result);
1289                 srp->header.host_status = host_byte(result);
1290                 srp->header.driver_status = driver_byte(result);
1291                 if ((sdp->sgdebug > 0) &&
1292                     ((CHECK_CONDITION == srp->header.masked_status) ||
1293                      (COMMAND_TERMINATED == srp->header.masked_status)))
1294                         __scsi_print_sense("sg_cmd_done", sense,
1295                                            SCSI_SENSE_BUFFERSIZE);
1296
1297                 /* Following if statement is a patch supplied by Eric Youngdale */
1298                 if (driver_byte(result) != 0
1299                     && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1300                     && !scsi_sense_is_deferred(&sshdr)
1301                     && sshdr.sense_key == UNIT_ATTENTION
1302                     && sdp->device->removable) {
1303                         /* Detected possible disc change. Set the bit - this */
1304                         /* may be used if there are filesystems using this device */
1305                         sdp->device->changed = 1;
1306                 }
1307         }
1308         /* Rely on write phase to clean out srp status values, so no "else" */
1309
1310         write_lock_irqsave(&sfp->rq_list_lock, iflags);
1311         if (unlikely(srp->orphan)) {
1312                 if (sfp->keep_orphan)
1313                         srp->sg_io_owned = 0;
1314                 else
1315                         done = 0;
1316         }
1317         srp->done = done;
1318         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1319
1320         if (likely(done)) {
1321                 /* Now wake up any sg_read() that is waiting for this
1322                  * packet.
1323                  */
1324                 wake_up_interruptible(&sfp->read_wait);
1325                 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1326                 kref_put(&sfp->f_ref, sg_remove_sfp);
1327         } else {
1328                 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1329                 schedule_work(&srp->ew.work);
1330         }
1331 }
1332
1333 static const struct file_operations sg_fops = {
1334         .owner = THIS_MODULE,
1335         .read = sg_read,
1336         .write = sg_write,
1337         .poll = sg_poll,
1338         .unlocked_ioctl = sg_unlocked_ioctl,
1339 #ifdef CONFIG_COMPAT
1340         .compat_ioctl = sg_compat_ioctl,
1341 #endif
1342         .open = sg_open,
1343         .mmap = sg_mmap,
1344         .release = sg_release,
1345         .fasync = sg_fasync,
1346 };
1347
1348 static struct class *sg_sysfs_class;
1349
1350 static int sg_sysfs_valid = 0;
1351
1352 static Sg_device *sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1353 {
1354         struct request_queue *q = scsidp->request_queue;
1355         Sg_device *sdp;
1356         unsigned long iflags;
1357         int error;
1358         u32 k;
1359
1360         sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1361         if (!sdp) {
1362                 printk(KERN_WARNING "kmalloc Sg_device failure\n");
1363                 return ERR_PTR(-ENOMEM);
1364         }
1365
1366         if (!idr_pre_get(&sg_index_idr, GFP_KERNEL)) {
1367                 printk(KERN_WARNING "idr expansion Sg_device failure\n");
1368                 error = -ENOMEM;
1369                 goto out;
1370         }
1371
1372         write_lock_irqsave(&sg_index_lock, iflags);
1373
1374         error = idr_get_new(&sg_index_idr, sdp, &k);
1375         if (error) {
1376                 write_unlock_irqrestore(&sg_index_lock, iflags);
1377                 printk(KERN_WARNING "idr allocation Sg_device failure: %d\n",
1378                        error);
1379                 goto out;
1380         }
1381
1382         if (unlikely(k >= SG_MAX_DEVS))
1383                 goto overflow;
1384
1385         SCSI_LOG_TIMEOUT(3, printk("sg_alloc: dev=%d \n", k));
1386         sprintf(disk->disk_name, "sg%d", k);
1387         disk->first_minor = k;
1388         sdp->disk = disk;
1389         sdp->device = scsidp;
1390         INIT_LIST_HEAD(&sdp->sfds);
1391         init_waitqueue_head(&sdp->o_excl_wait);
1392         sdp->sg_tablesize = queue_max_segments(q);
1393         sdp->index = k;
1394         kref_init(&sdp->d_ref);
1395
1396         write_unlock_irqrestore(&sg_index_lock, iflags);
1397
1398         error = 0;
1399  out:
1400         if (error) {
1401                 kfree(sdp);
1402                 return ERR_PTR(error);
1403         }
1404         return sdp;
1405
1406  overflow:
1407         idr_remove(&sg_index_idr, k);
1408         write_unlock_irqrestore(&sg_index_lock, iflags);
1409         sdev_printk(KERN_WARNING, scsidp,
1410                     "Unable to attach sg device type=%d, minor "
1411                     "number exceeds %d\n", scsidp->type, SG_MAX_DEVS - 1);
1412         error = -ENODEV;
1413         goto out;
1414 }
1415
1416 static int
1417 sg_add(struct device *cl_dev, struct class_interface *cl_intf)
1418 {
1419         struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1420         struct gendisk *disk;
1421         Sg_device *sdp = NULL;
1422         struct cdev * cdev = NULL;
1423         int error;
1424         unsigned long iflags;
1425
1426         disk = alloc_disk(1);
1427         if (!disk) {
1428                 printk(KERN_WARNING "alloc_disk failed\n");
1429                 return -ENOMEM;
1430         }
1431         disk->major = SCSI_GENERIC_MAJOR;
1432
1433         error = -ENOMEM;
1434         cdev = cdev_alloc();
1435         if (!cdev) {
1436                 printk(KERN_WARNING "cdev_alloc failed\n");
1437                 goto out;
1438         }
1439         cdev->owner = THIS_MODULE;
1440         cdev->ops = &sg_fops;
1441
1442         sdp = sg_alloc(disk, scsidp);
1443         if (IS_ERR(sdp)) {
1444                 printk(KERN_WARNING "sg_alloc failed\n");
1445                 error = PTR_ERR(sdp);
1446                 goto out;
1447         }
1448
1449         error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1450         if (error)
1451                 goto cdev_add_err;
1452
1453         sdp->cdev = cdev;
1454         if (sg_sysfs_valid) {
1455                 struct device *sg_class_member;
1456
1457                 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1458                                                 MKDEV(SCSI_GENERIC_MAJOR,
1459                                                       sdp->index),
1460                                                 sdp, "%s", disk->disk_name);
1461                 if (IS_ERR(sg_class_member)) {
1462                         printk(KERN_ERR "sg_add: "
1463                                "device_create failed\n");
1464                         error = PTR_ERR(sg_class_member);
1465                         goto cdev_add_err;
1466                 }
1467                 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1468                                           &sg_class_member->kobj, "generic");
1469                 if (error)
1470                         printk(KERN_ERR "sg_add: unable to make symlink "
1471                                         "'generic' back to sg%d\n", sdp->index);
1472         } else
1473                 printk(KERN_WARNING "sg_add: sg_sys Invalid\n");
1474
1475         sdev_printk(KERN_NOTICE, scsidp,
1476                     "Attached scsi generic sg%d type %d\n", sdp->index,
1477                     scsidp->type);
1478
1479         dev_set_drvdata(cl_dev, sdp);
1480
1481         return 0;
1482
1483 cdev_add_err:
1484         write_lock_irqsave(&sg_index_lock, iflags);
1485         idr_remove(&sg_index_idr, sdp->index);
1486         write_unlock_irqrestore(&sg_index_lock, iflags);
1487         kfree(sdp);
1488
1489 out:
1490         put_disk(disk);
1491         if (cdev)
1492                 cdev_del(cdev);
1493         return error;
1494 }
1495
1496 static void sg_device_destroy(struct kref *kref)
1497 {
1498         struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1499         unsigned long flags;
1500
1501         /* CAUTION!  Note that the device can still be found via idr_find()
1502          * even though the refcount is 0.  Therefore, do idr_remove() BEFORE
1503          * any other cleanup.
1504          */
1505
1506         write_lock_irqsave(&sg_index_lock, flags);
1507         idr_remove(&sg_index_idr, sdp->index);
1508         write_unlock_irqrestore(&sg_index_lock, flags);
1509
1510         SCSI_LOG_TIMEOUT(3,
1511                 printk("sg_device_destroy: %s\n",
1512                         sdp->disk->disk_name));
1513
1514         put_disk(sdp->disk);
1515         kfree(sdp);
1516 }
1517
1518 static void sg_remove(struct device *cl_dev, struct class_interface *cl_intf)
1519 {
1520         struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1521         Sg_device *sdp = dev_get_drvdata(cl_dev);
1522         unsigned long iflags;
1523         Sg_fd *sfp;
1524
1525         if (!sdp || sdp->detached)
1526                 return;
1527
1528         SCSI_LOG_TIMEOUT(3, printk("sg_remove: %s\n", sdp->disk->disk_name));
1529
1530         /* Need a write lock to set sdp->detached. */
1531         write_lock_irqsave(&sg_index_lock, iflags);
1532         sdp->detached = 1;
1533         list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1534                 wake_up_interruptible(&sfp->read_wait);
1535                 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1536         }
1537         write_unlock_irqrestore(&sg_index_lock, iflags);
1538
1539         sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1540         device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1541         cdev_del(sdp->cdev);
1542         sdp->cdev = NULL;
1543
1544         sg_put_dev(sdp);
1545 }
1546
1547 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1548 module_param_named(def_reserved_size, def_reserved_size, int,
1549                    S_IRUGO | S_IWUSR);
1550 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1551
1552 MODULE_AUTHOR("Douglas Gilbert");
1553 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1554 MODULE_LICENSE("GPL");
1555 MODULE_VERSION(SG_VERSION_STR);
1556 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1557
1558 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1559                 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1560 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1561 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1562
1563 static int __init
1564 init_sg(void)
1565 {
1566         int rc;
1567
1568         if (scatter_elem_sz < PAGE_SIZE) {
1569                 scatter_elem_sz = PAGE_SIZE;
1570                 scatter_elem_sz_prev = scatter_elem_sz;
1571         }
1572         if (def_reserved_size >= 0)
1573                 sg_big_buff = def_reserved_size;
1574         else
1575                 def_reserved_size = sg_big_buff;
1576
1577         rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1578                                     SG_MAX_DEVS, "sg");
1579         if (rc)
1580                 return rc;
1581         sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1582         if ( IS_ERR(sg_sysfs_class) ) {
1583                 rc = PTR_ERR(sg_sysfs_class);
1584                 goto err_out;
1585         }
1586         sg_sysfs_valid = 1;
1587         rc = scsi_register_interface(&sg_interface);
1588         if (0 == rc) {
1589 #ifdef CONFIG_SCSI_PROC_FS
1590                 sg_proc_init();
1591 #endif                          /* CONFIG_SCSI_PROC_FS */
1592                 return 0;
1593         }
1594         class_destroy(sg_sysfs_class);
1595 err_out:
1596         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1597         return rc;
1598 }
1599
1600 static void __exit
1601 exit_sg(void)
1602 {
1603 #ifdef CONFIG_SCSI_PROC_FS
1604         sg_proc_cleanup();
1605 #endif                          /* CONFIG_SCSI_PROC_FS */
1606         scsi_unregister_interface(&sg_interface);
1607         class_destroy(sg_sysfs_class);
1608         sg_sysfs_valid = 0;
1609         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1610                                  SG_MAX_DEVS);
1611         idr_destroy(&sg_index_idr);
1612 }
1613
1614 static int sg_start_req(Sg_request *srp, unsigned char *cmd)
1615 {
1616         int res;
1617         struct request *rq;
1618         Sg_fd *sfp = srp->parentfp;
1619         sg_io_hdr_t *hp = &srp->header;
1620         int dxfer_len = (int) hp->dxfer_len;
1621         int dxfer_dir = hp->dxfer_direction;
1622         unsigned int iov_count = hp->iovec_count;
1623         Sg_scatter_hold *req_schp = &srp->data;
1624         Sg_scatter_hold *rsv_schp = &sfp->reserve;
1625         struct request_queue *q = sfp->parentdp->device->request_queue;
1626         struct rq_map_data *md, map_data;
1627         int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
1628
1629         SCSI_LOG_TIMEOUT(4, printk(KERN_INFO "sg_start_req: dxfer_len=%d\n",
1630                                    dxfer_len));
1631
1632         rq = blk_get_request(q, rw, GFP_ATOMIC);
1633         if (!rq)
1634                 return -ENOMEM;
1635
1636         memcpy(rq->cmd, cmd, hp->cmd_len);
1637
1638         rq->cmd_len = hp->cmd_len;
1639         rq->cmd_type = REQ_TYPE_BLOCK_PC;
1640
1641         srp->rq = rq;
1642         rq->end_io_data = srp;
1643         rq->sense = srp->sense_b;
1644         rq->retries = SG_DEFAULT_RETRIES;
1645
1646         if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1647                 return 0;
1648
1649         if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1650             dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1651             !sfp->parentdp->device->host->unchecked_isa_dma &&
1652             blk_rq_aligned(q, hp->dxferp, dxfer_len))
1653                 md = NULL;
1654         else
1655                 md = &map_data;
1656
1657         if (md) {
1658                 if (!sg_res_in_use(sfp) && dxfer_len <= rsv_schp->bufflen)
1659                         sg_link_reserve(sfp, srp, dxfer_len);
1660                 else {
1661                         res = sg_build_indirect(req_schp, sfp, dxfer_len);
1662                         if (res)
1663                                 return res;
1664                 }
1665
1666                 md->pages = req_schp->pages;
1667                 md->page_order = req_schp->page_order;
1668                 md->nr_entries = req_schp->k_use_sg;
1669                 md->offset = 0;
1670                 md->null_mapped = hp->dxferp ? 0 : 1;
1671                 if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1672                         md->from_user = 1;
1673                 else
1674                         md->from_user = 0;
1675         }
1676
1677         if (iov_count) {
1678                 int len, size = sizeof(struct sg_iovec) * iov_count;
1679                 struct iovec *iov;
1680
1681                 iov = kmalloc(size, GFP_ATOMIC);
1682                 if (!iov)
1683                         return -ENOMEM;
1684
1685                 if (copy_from_user(iov, hp->dxferp, size)) {
1686                         kfree(iov);
1687                         return -EFAULT;
1688                 }
1689
1690                 len = iov_length(iov, iov_count);
1691                 if (hp->dxfer_len < len) {
1692                         iov_count = iov_shorten(iov, iov_count, hp->dxfer_len);
1693                         len = hp->dxfer_len;
1694                 }
1695
1696                 res = blk_rq_map_user_iov(q, rq, md, (struct sg_iovec *)iov,
1697                                           iov_count,
1698                                           len, GFP_ATOMIC);
1699                 kfree(iov);
1700         } else
1701                 res = blk_rq_map_user(q, rq, md, hp->dxferp,
1702                                       hp->dxfer_len, GFP_ATOMIC);
1703
1704         if (!res) {
1705                 srp->bio = rq->bio;
1706
1707                 if (!md) {
1708                         req_schp->dio_in_use = 1;
1709                         hp->info |= SG_INFO_DIRECT_IO;
1710                 }
1711         }
1712         return res;
1713 }
1714
1715 static int sg_finish_rem_req(Sg_request * srp)
1716 {
1717         int ret = 0;
1718
1719         Sg_fd *sfp = srp->parentfp;
1720         Sg_scatter_hold *req_schp = &srp->data;
1721
1722         SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n", (int) srp->res_used));
1723         if (srp->rq) {
1724                 if (srp->bio)
1725                         ret = blk_rq_unmap_user(srp->bio);
1726
1727                 blk_put_request(srp->rq);
1728         }
1729
1730         if (srp->res_used)
1731                 sg_unlink_reserve(sfp, srp);
1732         else
1733                 sg_remove_scat(req_schp);
1734
1735         sg_remove_request(sfp, srp);
1736
1737         return ret;
1738 }
1739
1740 static int
1741 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1742 {
1743         int sg_bufflen = tablesize * sizeof(struct page *);
1744         gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1745
1746         schp->pages = kzalloc(sg_bufflen, gfp_flags);
1747         if (!schp->pages)
1748                 return -ENOMEM;
1749         schp->sglist_len = sg_bufflen;
1750         return tablesize;       /* number of scat_gath elements allocated */
1751 }
1752
1753 static int
1754 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1755 {
1756         int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1757         int sg_tablesize = sfp->parentdp->sg_tablesize;
1758         int blk_size = buff_size, order;
1759         gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
1760
1761         if (blk_size < 0)
1762                 return -EFAULT;
1763         if (0 == blk_size)
1764                 ++blk_size;     /* don't know why */
1765         /* round request up to next highest SG_SECTOR_SZ byte boundary */
1766         blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1767         SCSI_LOG_TIMEOUT(4, printk("sg_build_indirect: buff_size=%d, blk_size=%d\n",
1768                                    buff_size, blk_size));
1769
1770         /* N.B. ret_sz carried into this block ... */
1771         mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1772         if (mx_sc_elems < 0)
1773                 return mx_sc_elems;     /* most likely -ENOMEM */
1774
1775         num = scatter_elem_sz;
1776         if (unlikely(num != scatter_elem_sz_prev)) {
1777                 if (num < PAGE_SIZE) {
1778                         scatter_elem_sz = PAGE_SIZE;
1779                         scatter_elem_sz_prev = PAGE_SIZE;
1780                 } else
1781                         scatter_elem_sz_prev = num;
1782         }
1783
1784         if (sfp->low_dma)
1785                 gfp_mask |= GFP_DMA;
1786
1787         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1788                 gfp_mask |= __GFP_ZERO;
1789
1790         order = get_order(num);
1791 retry:
1792         ret_sz = 1 << (PAGE_SHIFT + order);
1793
1794         for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1795              k++, rem_sz -= ret_sz) {
1796
1797                 num = (rem_sz > scatter_elem_sz_prev) ?
1798                         scatter_elem_sz_prev : rem_sz;
1799
1800                 schp->pages[k] = alloc_pages(gfp_mask, order);
1801                 if (!schp->pages[k])
1802                         goto out;
1803
1804                 if (num == scatter_elem_sz_prev) {
1805                         if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1806                                 scatter_elem_sz = ret_sz;
1807                                 scatter_elem_sz_prev = ret_sz;
1808                         }
1809                 }
1810
1811                 SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k=%d, num=%d, "
1812                                  "ret_sz=%d\n", k, num, ret_sz));
1813         }               /* end of for loop */
1814
1815         schp->page_order = order;
1816         schp->k_use_sg = k;
1817         SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, "
1818                          "rem_sz=%d\n", k, rem_sz));
1819
1820         schp->bufflen = blk_size;
1821         if (rem_sz > 0) /* must have failed */
1822                 return -ENOMEM;
1823         return 0;
1824 out:
1825         for (i = 0; i < k; i++)
1826                 __free_pages(schp->pages[i], order);
1827
1828         if (--order >= 0)
1829                 goto retry;
1830
1831         return -ENOMEM;
1832 }
1833
1834 static void
1835 sg_remove_scat(Sg_scatter_hold * schp)
1836 {
1837         SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1838         if (schp->pages && schp->sglist_len > 0) {
1839                 if (!schp->dio_in_use) {
1840                         int k;
1841
1842                         for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1843                                 SCSI_LOG_TIMEOUT(5, printk(
1844                                     "sg_remove_scat: k=%d, pg=0x%p\n",
1845                                     k, schp->pages[k]));
1846                                 __free_pages(schp->pages[k], schp->page_order);
1847                         }
1848
1849                         kfree(schp->pages);
1850                 }
1851         }
1852         memset(schp, 0, sizeof (*schp));
1853 }
1854
1855 static int
1856 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1857 {
1858         Sg_scatter_hold *schp = &srp->data;
1859         int k, num;
1860
1861         SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n",
1862                                    num_read_xfer));
1863         if ((!outp) || (num_read_xfer <= 0))
1864                 return 0;
1865
1866         num = 1 << (PAGE_SHIFT + schp->page_order);
1867         for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1868                 if (num > num_read_xfer) {
1869                         if (__copy_to_user(outp, page_address(schp->pages[k]),
1870                                            num_read_xfer))
1871                                 return -EFAULT;
1872                         break;
1873                 } else {
1874                         if (__copy_to_user(outp, page_address(schp->pages[k]),
1875                                            num))
1876                                 return -EFAULT;
1877                         num_read_xfer -= num;
1878                         if (num_read_xfer <= 0)
1879                                 break;
1880                         outp += num;
1881                 }
1882         }
1883
1884         return 0;
1885 }
1886
1887 static void
1888 sg_build_reserve(Sg_fd * sfp, int req_size)
1889 {
1890         Sg_scatter_hold *schp = &sfp->reserve;
1891
1892         SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
1893         do {
1894                 if (req_size < PAGE_SIZE)
1895                         req_size = PAGE_SIZE;
1896                 if (0 == sg_build_indirect(schp, sfp, req_size))
1897                         return;
1898                 else
1899                         sg_remove_scat(schp);
1900                 req_size >>= 1; /* divide by 2 */
1901         } while (req_size > (PAGE_SIZE / 2));
1902 }
1903
1904 static void
1905 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
1906 {
1907         Sg_scatter_hold *req_schp = &srp->data;
1908         Sg_scatter_hold *rsv_schp = &sfp->reserve;
1909         int k, num, rem;
1910
1911         srp->res_used = 1;
1912         SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
1913         rem = size;
1914
1915         num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1916         for (k = 0; k < rsv_schp->k_use_sg; k++) {
1917                 if (rem <= num) {
1918                         req_schp->k_use_sg = k + 1;
1919                         req_schp->sglist_len = rsv_schp->sglist_len;
1920                         req_schp->pages = rsv_schp->pages;
1921
1922                         req_schp->bufflen = size;
1923                         req_schp->page_order = rsv_schp->page_order;
1924                         break;
1925                 } else
1926                         rem -= num;
1927         }
1928
1929         if (k >= rsv_schp->k_use_sg)
1930                 SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
1931 }
1932
1933 static void
1934 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
1935 {
1936         Sg_scatter_hold *req_schp = &srp->data;
1937
1938         SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->k_use_sg=%d\n",
1939                                    (int) req_schp->k_use_sg));
1940         req_schp->k_use_sg = 0;
1941         req_schp->bufflen = 0;
1942         req_schp->pages = NULL;
1943         req_schp->page_order = 0;
1944         req_schp->sglist_len = 0;
1945         sfp->save_scat_len = 0;
1946         srp->res_used = 0;
1947 }
1948
1949 static Sg_request *
1950 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
1951 {
1952         Sg_request *resp;
1953         unsigned long iflags;
1954
1955         write_lock_irqsave(&sfp->rq_list_lock, iflags);
1956         for (resp = sfp->headrp; resp; resp = resp->nextrp) {
1957                 /* look for requests that are ready + not SG_IO owned */
1958                 if ((1 == resp->done) && (!resp->sg_io_owned) &&
1959                     ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
1960                         resp->done = 2; /* guard against other readers */
1961                         break;
1962                 }
1963         }
1964         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1965         return resp;
1966 }
1967
1968 /* always adds to end of list */
1969 static Sg_request *
1970 sg_add_request(Sg_fd * sfp)
1971 {
1972         int k;
1973         unsigned long iflags;
1974         Sg_request *resp;
1975         Sg_request *rp = sfp->req_arr;
1976
1977         write_lock_irqsave(&sfp->rq_list_lock, iflags);
1978         resp = sfp->headrp;
1979         if (!resp) {
1980                 memset(rp, 0, sizeof (Sg_request));
1981                 rp->parentfp = sfp;
1982                 resp = rp;
1983                 sfp->headrp = resp;
1984         } else {
1985                 if (0 == sfp->cmd_q)
1986                         resp = NULL;    /* command queuing disallowed */
1987                 else {
1988                         for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
1989                                 if (!rp->parentfp)
1990                                         break;
1991                         }
1992                         if (k < SG_MAX_QUEUE) {
1993                                 memset(rp, 0, sizeof (Sg_request));
1994                                 rp->parentfp = sfp;
1995                                 while (resp->nextrp)
1996                                         resp = resp->nextrp;
1997                                 resp->nextrp = rp;
1998                                 resp = rp;
1999                         } else
2000                                 resp = NULL;
2001                 }
2002         }
2003         if (resp) {
2004                 resp->nextrp = NULL;
2005                 resp->header.duration = jiffies_to_msecs(jiffies);
2006         }
2007         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2008         return resp;
2009 }
2010
2011 /* Return of 1 for found; 0 for not found */
2012 static int
2013 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2014 {
2015         Sg_request *prev_rp;
2016         Sg_request *rp;
2017         unsigned long iflags;
2018         int res = 0;
2019
2020         if ((!sfp) || (!srp) || (!sfp->headrp))
2021                 return res;
2022         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2023         prev_rp = sfp->headrp;
2024         if (srp == prev_rp) {
2025                 sfp->headrp = prev_rp->nextrp;
2026                 prev_rp->parentfp = NULL;
2027                 res = 1;
2028         } else {
2029                 while ((rp = prev_rp->nextrp)) {
2030                         if (srp == rp) {
2031                                 prev_rp->nextrp = rp->nextrp;
2032                                 rp->parentfp = NULL;
2033                                 res = 1;
2034                                 break;
2035                         }
2036                         prev_rp = rp;
2037                 }
2038         }
2039         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2040         return res;
2041 }
2042
2043 static Sg_fd *
2044 sg_add_sfp(Sg_device * sdp, int dev)
2045 {
2046         Sg_fd *sfp;
2047         unsigned long iflags;
2048         int bufflen;
2049
2050         sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2051         if (!sfp)
2052                 return NULL;
2053
2054         init_waitqueue_head(&sfp->read_wait);
2055         rwlock_init(&sfp->rq_list_lock);
2056
2057         kref_init(&sfp->f_ref);
2058         sfp->timeout = SG_DEFAULT_TIMEOUT;
2059         sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2060         sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2061         sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
2062             sdp->device->host->unchecked_isa_dma : 1;
2063         sfp->cmd_q = SG_DEF_COMMAND_Q;
2064         sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2065         sfp->parentdp = sdp;
2066         write_lock_irqsave(&sg_index_lock, iflags);
2067         list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2068         write_unlock_irqrestore(&sg_index_lock, iflags);
2069         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));
2070         if (unlikely(sg_big_buff != def_reserved_size))
2071                 sg_big_buff = def_reserved_size;
2072
2073         bufflen = min_t(int, sg_big_buff,
2074                         queue_max_sectors(sdp->device->request_queue) * 512);
2075         sg_build_reserve(sfp, bufflen);
2076         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp:   bufflen=%d, k_use_sg=%d\n",
2077                            sfp->reserve.bufflen, sfp->reserve.k_use_sg));
2078
2079         kref_get(&sdp->d_ref);
2080         __module_get(THIS_MODULE);
2081         return sfp;
2082 }
2083
2084 static void sg_remove_sfp_usercontext(struct work_struct *work)
2085 {
2086         struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2087         struct sg_device *sdp = sfp->parentdp;
2088
2089         /* Cleanup any responses which were never read(). */
2090         while (sfp->headrp)
2091                 sg_finish_rem_req(sfp->headrp);
2092
2093         if (sfp->reserve.bufflen > 0) {
2094                 SCSI_LOG_TIMEOUT(6,
2095                         printk("sg_remove_sfp:    bufflen=%d, k_use_sg=%d\n",
2096                                 (int) sfp->reserve.bufflen,
2097                                 (int) sfp->reserve.k_use_sg));
2098                 sg_remove_scat(&sfp->reserve);
2099         }
2100
2101         SCSI_LOG_TIMEOUT(6,
2102                 printk("sg_remove_sfp: %s, sfp=0x%p\n",
2103                         sdp->disk->disk_name,
2104                         sfp));
2105         kfree(sfp);
2106
2107         scsi_device_put(sdp->device);
2108         sg_put_dev(sdp);
2109         module_put(THIS_MODULE);
2110 }
2111
2112 static void sg_remove_sfp(struct kref *kref)
2113 {
2114         struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2115         struct sg_device *sdp = sfp->parentdp;
2116         unsigned long iflags;
2117
2118         write_lock_irqsave(&sg_index_lock, iflags);
2119         list_del(&sfp->sfd_siblings);
2120         write_unlock_irqrestore(&sg_index_lock, iflags);
2121         wake_up_interruptible(&sdp->o_excl_wait);
2122
2123         INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2124         schedule_work(&sfp->ew.work);
2125 }
2126
2127 static int
2128 sg_res_in_use(Sg_fd * sfp)
2129 {
2130         const Sg_request *srp;
2131         unsigned long iflags;
2132
2133         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2134         for (srp = sfp->headrp; srp; srp = srp->nextrp)
2135                 if (srp->res_used)
2136                         break;
2137         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2138         return srp ? 1 : 0;
2139 }
2140
2141 #ifdef CONFIG_SCSI_PROC_FS
2142 static int
2143 sg_idr_max_id(int id, void *p, void *data)
2144 {
2145         int *k = data;
2146
2147         if (*k < id)
2148                 *k = id;
2149
2150         return 0;
2151 }
2152
2153 static int
2154 sg_last_dev(void)
2155 {
2156         int k = -1;
2157         unsigned long iflags;
2158
2159         read_lock_irqsave(&sg_index_lock, iflags);
2160         idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2161         read_unlock_irqrestore(&sg_index_lock, iflags);
2162         return k + 1;           /* origin 1 */
2163 }
2164 #endif
2165
2166 /* must be called with sg_index_lock held */
2167 static Sg_device *sg_lookup_dev(int dev)
2168 {
2169         return idr_find(&sg_index_idr, dev);
2170 }
2171
2172 static Sg_device *sg_get_dev(int dev)
2173 {
2174         struct sg_device *sdp;
2175         unsigned long flags;
2176
2177         read_lock_irqsave(&sg_index_lock, flags);
2178         sdp = sg_lookup_dev(dev);
2179         if (!sdp)
2180                 sdp = ERR_PTR(-ENXIO);
2181         else if (sdp->detached) {
2182                 /* If sdp->detached, then the refcount may already be 0, in
2183                  * which case it would be a bug to do kref_get().
2184                  */
2185                 sdp = ERR_PTR(-ENODEV);
2186         } else
2187                 kref_get(&sdp->d_ref);
2188         read_unlock_irqrestore(&sg_index_lock, flags);
2189
2190         return sdp;
2191 }
2192
2193 static void sg_put_dev(struct sg_device *sdp)
2194 {
2195         kref_put(&sdp->d_ref, sg_device_destroy);
2196 }
2197
2198 #ifdef CONFIG_SCSI_PROC_FS
2199
2200 static struct proc_dir_entry *sg_proc_sgp = NULL;
2201
2202 static char sg_proc_sg_dirname[] = "scsi/sg";
2203
2204 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2205
2206 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2207 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2208                                   size_t count, loff_t *off);
2209 static const struct file_operations adio_fops = {
2210         .owner = THIS_MODULE,
2211         .open = sg_proc_single_open_adio,
2212         .read = seq_read,
2213         .llseek = seq_lseek,
2214         .write = sg_proc_write_adio,
2215         .release = single_release,
2216 };
2217
2218 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2219 static ssize_t sg_proc_write_dressz(struct file *filp,
2220                 const char __user *buffer, size_t count, loff_t *off);
2221 static const struct file_operations dressz_fops = {
2222         .owner = THIS_MODULE,
2223         .open = sg_proc_single_open_dressz,
2224         .read = seq_read,
2225         .llseek = seq_lseek,
2226         .write = sg_proc_write_dressz,
2227         .release = single_release,
2228 };
2229
2230 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2231 static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2232 static const struct file_operations version_fops = {
2233         .owner = THIS_MODULE,
2234         .open = sg_proc_single_open_version,
2235         .read = seq_read,
2236         .llseek = seq_lseek,
2237         .release = single_release,
2238 };
2239
2240 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2241 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2242 static const struct file_operations devhdr_fops = {
2243         .owner = THIS_MODULE,
2244         .open = sg_proc_single_open_devhdr,
2245         .read = seq_read,
2246         .llseek = seq_lseek,
2247         .release = single_release,
2248 };
2249
2250 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2251 static int sg_proc_open_dev(struct inode *inode, struct file *file);
2252 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2253 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2254 static void dev_seq_stop(struct seq_file *s, void *v);
2255 static const struct file_operations dev_fops = {
2256         .owner = THIS_MODULE,
2257         .open = sg_proc_open_dev,
2258         .read = seq_read,
2259         .llseek = seq_lseek,
2260         .release = seq_release,
2261 };
2262 static const struct seq_operations dev_seq_ops = {
2263         .start = dev_seq_start,
2264         .next  = dev_seq_next,
2265         .stop  = dev_seq_stop,
2266         .show  = sg_proc_seq_show_dev,
2267 };
2268
2269 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2270 static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2271 static const struct file_operations devstrs_fops = {
2272         .owner = THIS_MODULE,
2273         .open = sg_proc_open_devstrs,
2274         .read = seq_read,
2275         .llseek = seq_lseek,
2276         .release = seq_release,
2277 };
2278 static const struct seq_operations devstrs_seq_ops = {
2279         .start = dev_seq_start,
2280         .next  = dev_seq_next,
2281         .stop  = dev_seq_stop,
2282         .show  = sg_proc_seq_show_devstrs,
2283 };
2284
2285 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2286 static int sg_proc_open_debug(struct inode *inode, struct file *file);
2287 static const struct file_operations debug_fops = {
2288         .owner = THIS_MODULE,
2289         .open = sg_proc_open_debug,
2290         .read = seq_read,
2291         .llseek = seq_lseek,
2292         .release = seq_release,
2293 };
2294 static const struct seq_operations debug_seq_ops = {
2295         .start = dev_seq_start,
2296         .next  = dev_seq_next,
2297         .stop  = dev_seq_stop,
2298         .show  = sg_proc_seq_show_debug,
2299 };
2300
2301
2302 struct sg_proc_leaf {
2303         const char * name;
2304         const struct file_operations * fops;
2305 };
2306
2307 static struct sg_proc_leaf sg_proc_leaf_arr[] = {
2308         {"allow_dio", &adio_fops},
2309         {"debug", &debug_fops},
2310         {"def_reserved_size", &dressz_fops},
2311         {"device_hdr", &devhdr_fops},
2312         {"devices", &dev_fops},
2313         {"device_strs", &devstrs_fops},
2314         {"version", &version_fops}
2315 };
2316
2317 static int
2318 sg_proc_init(void)
2319 {
2320         int k, mask;
2321         int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2322         struct sg_proc_leaf * leaf;
2323
2324         sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2325         if (!sg_proc_sgp)
2326                 return 1;
2327         for (k = 0; k < num_leaves; ++k) {
2328                 leaf = &sg_proc_leaf_arr[k];
2329                 mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2330                 proc_create(leaf->name, mask, sg_proc_sgp, leaf->fops);
2331         }
2332         return 0;
2333 }
2334
2335 static void
2336 sg_proc_cleanup(void)
2337 {
2338         int k;
2339         int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2340
2341         if (!sg_proc_sgp)
2342                 return;
2343         for (k = 0; k < num_leaves; ++k)
2344                 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2345         remove_proc_entry(sg_proc_sg_dirname, NULL);
2346 }
2347
2348
2349 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2350 {
2351         seq_printf(s, "%d\n", *((int *)s->private));
2352         return 0;
2353 }
2354
2355 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2356 {
2357         return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2358 }
2359
2360 static ssize_t
2361 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2362                    size_t count, loff_t *off)
2363 {
2364         int num;
2365         char buff[11];
2366
2367         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2368                 return -EACCES;
2369         num = (count < 10) ? count : 10;
2370         if (copy_from_user(buff, buffer, num))
2371                 return -EFAULT;
2372         buff[num] = '\0';
2373         sg_allow_dio = simple_strtoul(buff, NULL, 10) ? 1 : 0;
2374         return count;
2375 }
2376
2377 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2378 {
2379         return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2380 }
2381
2382 static ssize_t
2383 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2384                      size_t count, loff_t *off)
2385 {
2386         int num;
2387         unsigned long k = ULONG_MAX;
2388         char buff[11];
2389
2390         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2391                 return -EACCES;
2392         num = (count < 10) ? count : 10;
2393         if (copy_from_user(buff, buffer, num))
2394                 return -EFAULT;
2395         buff[num] = '\0';
2396         k = simple_strtoul(buff, NULL, 10);
2397         if (k <= 1048576) {     /* limit "big buff" to 1 MB */
2398                 sg_big_buff = k;
2399                 return count;
2400         }
2401         return -ERANGE;
2402 }
2403
2404 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2405 {
2406         seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2407                    sg_version_date);
2408         return 0;
2409 }
2410
2411 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2412 {
2413         return single_open(file, sg_proc_seq_show_version, NULL);
2414 }
2415
2416 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2417 {
2418         seq_printf(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\t"
2419                    "online\n");
2420         return 0;
2421 }
2422
2423 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2424 {
2425         return single_open(file, sg_proc_seq_show_devhdr, NULL);
2426 }
2427
2428 struct sg_proc_deviter {
2429         loff_t  index;
2430         size_t  max;
2431 };
2432
2433 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2434 {
2435         struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2436
2437         s->private = it;
2438         if (! it)
2439                 return NULL;
2440
2441         it->index = *pos;
2442         it->max = sg_last_dev();
2443         if (it->index >= it->max)
2444                 return NULL;
2445         return it;
2446 }
2447
2448 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2449 {
2450         struct sg_proc_deviter * it = s->private;
2451
2452         *pos = ++it->index;
2453         return (it->index < it->max) ? it : NULL;
2454 }
2455
2456 static void dev_seq_stop(struct seq_file *s, void *v)
2457 {
2458         kfree(s->private);
2459 }
2460
2461 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2462 {
2463         return seq_open(file, &dev_seq_ops);
2464 }
2465
2466 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2467 {
2468         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2469         Sg_device *sdp;
2470         struct scsi_device *scsidp;
2471         unsigned long iflags;
2472
2473         read_lock_irqsave(&sg_index_lock, iflags);
2474         sdp = it ? sg_lookup_dev(it->index) : NULL;
2475         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2476                 seq_printf(s, "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n",
2477                               scsidp->host->host_no, scsidp->channel,
2478                               scsidp->id, scsidp->lun, (int) scsidp->type,
2479                               1,
2480                               (int) scsidp->queue_depth,
2481                               (int) scsidp->device_busy,
2482                               (int) scsi_device_online(scsidp));
2483         else
2484                 seq_printf(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2485         read_unlock_irqrestore(&sg_index_lock, iflags);
2486         return 0;
2487 }
2488
2489 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2490 {
2491         return seq_open(file, &devstrs_seq_ops);
2492 }
2493
2494 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2495 {
2496         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2497         Sg_device *sdp;
2498         struct scsi_device *scsidp;
2499         unsigned long iflags;
2500
2501         read_lock_irqsave(&sg_index_lock, iflags);
2502         sdp = it ? sg_lookup_dev(it->index) : NULL;
2503         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2504                 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2505                            scsidp->vendor, scsidp->model, scsidp->rev);
2506         else
2507                 seq_printf(s, "<no active device>\n");
2508         read_unlock_irqrestore(&sg_index_lock, iflags);
2509         return 0;
2510 }
2511
2512 /* must be called while holding sg_index_lock */
2513 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2514 {
2515         int k, m, new_interface, blen, usg;
2516         Sg_request *srp;
2517         Sg_fd *fp;
2518         const sg_io_hdr_t *hp;
2519         const char * cp;
2520         unsigned int ms;
2521
2522         k = 0;
2523         list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2524                 k++;
2525                 read_lock(&fp->rq_list_lock); /* irqs already disabled */
2526                 seq_printf(s, "   FD(%d): timeout=%dms bufflen=%d "
2527                            "(res)sgat=%d low_dma=%d\n", k,
2528                            jiffies_to_msecs(fp->timeout),
2529                            fp->reserve.bufflen,
2530                            (int) fp->reserve.k_use_sg,
2531                            (int) fp->low_dma);
2532                 seq_printf(s, "   cmd_q=%d f_packid=%d k_orphan=%d closed=%d\n",
2533                            (int) fp->cmd_q, (int) fp->force_packid,
2534                            (int) fp->keep_orphan, (int) fp->closed);
2535                 for (m = 0, srp = fp->headrp;
2536                                 srp != NULL;
2537                                 ++m, srp = srp->nextrp) {
2538                         hp = &srp->header;
2539                         new_interface = (hp->interface_id == '\0') ? 0 : 1;
2540                         if (srp->res_used) {
2541                                 if (new_interface &&
2542                                     (SG_FLAG_MMAP_IO & hp->flags))
2543                                         cp = "     mmap>> ";
2544                                 else
2545                                         cp = "     rb>> ";
2546                         } else {
2547                                 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2548                                         cp = "     dio>> ";
2549                                 else
2550                                         cp = "     ";
2551                         }
2552                         seq_printf(s, cp);
2553                         blen = srp->data.bufflen;
2554                         usg = srp->data.k_use_sg;
2555                         seq_printf(s, srp->done ?
2556                                    ((1 == srp->done) ?  "rcv:" : "fin:")
2557                                    : "act:");
2558                         seq_printf(s, " id=%d blen=%d",
2559                                    srp->header.pack_id, blen);
2560                         if (srp->done)
2561                                 seq_printf(s, " dur=%d", hp->duration);
2562                         else {
2563                                 ms = jiffies_to_msecs(jiffies);
2564                                 seq_printf(s, " t_o/elap=%d/%d",
2565                                         (new_interface ? hp->timeout :
2566                                                   jiffies_to_msecs(fp->timeout)),
2567                                         (ms > hp->duration ? ms - hp->duration : 0));
2568                         }
2569                         seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2570                                    (int) srp->data.cmd_opcode);
2571                 }
2572                 if (0 == m)
2573                         seq_printf(s, "     No requests active\n");
2574                 read_unlock(&fp->rq_list_lock);
2575         }
2576 }
2577
2578 static int sg_proc_open_debug(struct inode *inode, struct file *file)
2579 {
2580         return seq_open(file, &debug_seq_ops);
2581 }
2582
2583 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2584 {
2585         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2586         Sg_device *sdp;
2587         unsigned long iflags;
2588
2589         if (it && (0 == it->index)) {
2590                 seq_printf(s, "max_active_device=%d(origin 1)\n",
2591                            (int)it->max);
2592                 seq_printf(s, " def_reserved_size=%d\n", sg_big_buff);
2593         }
2594
2595         read_lock_irqsave(&sg_index_lock, iflags);
2596         sdp = it ? sg_lookup_dev(it->index) : NULL;
2597         if (sdp && !list_empty(&sdp->sfds)) {
2598                 struct scsi_device *scsidp = sdp->device;
2599
2600                 seq_printf(s, " >>> device=%s ", sdp->disk->disk_name);
2601                 if (sdp->detached)
2602                         seq_printf(s, "detached pending close ");
2603                 else
2604                         seq_printf
2605                             (s, "scsi%d chan=%d id=%d lun=%d   em=%d",
2606                              scsidp->host->host_no,
2607                              scsidp->channel, scsidp->id,
2608                              scsidp->lun,
2609                              scsidp->host->hostt->emulated);
2610                 seq_printf(s, " sg_tablesize=%d excl=%d\n",
2611                            sdp->sg_tablesize, sdp->exclude);
2612                 sg_proc_debug_helper(s, sdp);
2613         }
2614         read_unlock_irqrestore(&sg_index_lock, iflags);
2615         return 0;
2616 }
2617
2618 #endif                          /* CONFIG_SCSI_PROC_FS */
2619
2620 module_init(init_sg);
2621 module_exit(exit_sg);