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