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