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   1 /*
   2  *  History:
   3  *  Started: Aug 9 by Lawrence Foard (entropy@world.std.com),
   4  *           to allow user process control of SCSI devices.
   5  *  Development Sponsored by Killy Corp. NY NY
   6  *
   7  * Original driver (sg.c):
   8  *        Copyright (C) 1992 Lawrence Foard
   9  * Version 2 and 3 extensions to driver:
  10  *        Copyright (C) 1998 - 2005 Douglas Gilbert
  11  *
  12  *  Modified  19-JAN-1998  Richard Gooch <rgooch@atnf.csiro.au>  Devfs support
  13  *
  14  * This program is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2, or (at your option)
  17  * any later version.
  18  *
  19  */
  20
  21 static int sg_version_num = 30534;      /* 2 digits for each component */
  22 #define SG_VERSION_STR "3.5.34"
  23
  24 /*
  25  *  D. P. Gilbert (dgilbert@interlog.com, dougg@triode.net.au), notes:
  26  *      - scsi logging is available via SCSI_LOG_TIMEOUT macros. First
  27  *        the kernel/module needs to be built with CONFIG_SCSI_LOGGING
  28  *        (otherwise the macros compile to empty statements).
  29  *
  30  */
  31 #include <linux/module.h>
  32
  33 #include <linux/fs.h>
  34 #include <linux/kernel.h>
  35 #include <linux/sched.h>
  36 #include <linux/string.h>
  37 #include <linux/mm.h>
  38 #include <linux/errno.h>
  39 #include <linux/mtio.h>
  40 #include <linux/ioctl.h>
  41 #include <linux/fcntl.h>
  42 #include <linux/init.h>
  43 #include <linux/poll.h>
  44 #include <linux/moduleparam.h>
  45 #include <linux/cdev.h>
  46 #include <linux/idr.h>
  47 #include <linux/seq_file.h>
  48 #include <linux/blkdev.h>
  49 #include <linux/delay.h>
  50 #include <linux/blktrace_api.h>
  51 #include <linux/smp_lock.h>
  52
  53 #include "scsi.h"
  54 #include <scsi/scsi_dbg.h>
  55 #include <scsi/scsi_host.h>
  56 #include <scsi/scsi_driver.h>
  57 #include <scsi/scsi_ioctl.h>
  58 #include <scsi/sg.h>
  59
  60 #include "scsi_logging.h"
  61
  62 #ifdef CONFIG_SCSI_PROC_FS
  63 #include <linux/proc_fs.h>
  64 static char *sg_version_date = "20061027";
  65
  66 static int sg_proc_init(void);
  67 static void sg_proc_cleanup(void);
  68 #endif
  69
  70 #define SG_ALLOW_DIO_DEF 0
  71
  72 #define SG_MAX_DEVS 32768
  73
  74 /*
  75  * Suppose you want to calculate the formula muldiv(x,m,d)=int(x * m / d)
  76  * Then when using 32 bit integers x * m may overflow during the calculation.
  77  * Replacing muldiv(x) by muldiv(x)=((x % d) * m) / d + int(x / d) * m
  78  * calculates the same, but prevents the overflow when both m and d
  79  * are "small" numbers (like HZ and USER_HZ).
  80  * Of course an overflow is inavoidable if the result of muldiv doesn't fit
  81  * in 32 bits.
  82  */
  83 #define MULDIV(X,MUL,DIV) ((((X % DIV) * MUL) / DIV) + ((X / DIV) * MUL))
  84
  85 #define SG_DEFAULT_TIMEOUT MULDIV(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
  86
  87 int sg_big_buff = SG_DEF_RESERVED_SIZE;
  88 /* N.B. This variable is readable and writeable via
  89    /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
  90    of this size (or less if there is not enough memory) will be reserved
  91    for use by this file descriptor. [Deprecated usage: this variable is also
  92    readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
  93    the kernel (i.e. it is not a module).] */
  94 static int def_reserved_size = -1;      /* picks up init parameter */
  95 static int sg_allow_dio = SG_ALLOW_DIO_DEF;
  96
  97 static int scatter_elem_sz = SG_SCATTER_SZ;
  98 static int scatter_elem_sz_prev = SG_SCATTER_SZ;
  99
 100 #define SG_SECTOR_SZ 512
 101 #define SG_SECTOR_MSK (SG_SECTOR_SZ - 1)
 102
 103 static int sg_add(struct device *, struct class_interface *);
 104 static void sg_remove(struct device *, struct class_interface *);
 105
 106 static DEFINE_IDR(sg_index_idr);
 107 static DEFINE_RWLOCK(sg_index_lock);    /* Also used to lock
 108                                                            file descriptor list for device */
 109
 110 static struct class_interface sg_interface = {
 111         .add_dev        = sg_add,
 112         .remove_dev     = sg_remove,
 113 };
 114
 115 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
 116         unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
 117         unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */
 118         unsigned bufflen;       /* Size of (aggregate) data buffer */
 119         struct page **pages;
 120         int page_order;
 121         char dio_in_use;        /* 0->indirect IO (or mmap), 1->dio */
 122         unsigned char cmd_opcode; /* first byte of command */
 123 } Sg_scatter_hold;
 124
 125 struct sg_device;               /* forward declarations */
 126 struct sg_fd;
 127
 128 typedef struct sg_request {     /* SG_MAX_QUEUE requests outstanding per file */
 129         struct sg_request *nextrp;      /* NULL -> tail request (slist) */
 130         struct sg_fd *parentfp; /* NULL -> not in use */
 131         Sg_scatter_hold data;   /* hold buffer, perhaps scatter list */
 132         sg_io_hdr_t header;     /* scsi command+info, see <scsi/sg.h> */
 133         unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
 134         char res_used;          /* 1 -> using reserve buffer, 0 -> not ... */
 135         char orphan;            /* 1 -> drop on sight, 0 -> normal */
 136         char sg_io_owned;       /* 1 -> packet belongs to SG_IO */
 137         volatile char done;     /* 0->before bh, 1->before read, 2->read */
 138         struct request *rq;
 139         struct bio *bio;
 140 } Sg_request;
 141
 142 typedef struct sg_fd {          /* holds the state of a file descriptor */
 143         struct sg_fd *nextfp;   /* NULL when last opened fd on this device */
 144         struct sg_device *parentdp;     /* owning device */
 145         wait_queue_head_t read_wait;    /* queue read until command done */
 146         rwlock_t rq_list_lock;  /* protect access to list in req_arr */
 147         int timeout;            /* defaults to SG_DEFAULT_TIMEOUT      */
 148         int timeout_user;       /* defaults to SG_DEFAULT_TIMEOUT_USER */
 149         Sg_scatter_hold reserve;        /* buffer held for this file descriptor */
 150         unsigned save_scat_len; /* original length of trunc. scat. element */
 151         Sg_request *headrp;     /* head of request slist, NULL->empty */
 152         struct fasync_struct *async_qp; /* used by asynchronous notification */
 153         Sg_request req_arr[SG_MAX_QUEUE];       /* used as singly-linked list */
 154         char low_dma;           /* as in parent but possibly overridden to 1 */
 155         char force_packid;      /* 1 -> pack_id input to read(), 0 -> ignored */
 156         volatile char closed;   /* 1 -> fd closed but request(s) outstanding */
 157         char cmd_q;             /* 1 -> allow command queuing, 0 -> don't */
 158         char next_cmd_len;      /* 0 -> automatic (def), >0 -> use on next write() */
 159         char keep_orphan;       /* 0 -> drop orphan (def), 1 -> keep for read() */
 160         char mmap_called;       /* 0 -> mmap() never called on this fd */
 161 } Sg_fd;
 162
 163 typedef struct sg_device { /* holds the state of each scsi generic device */
 164         struct scsi_device *device;
 165         wait_queue_head_t o_excl_wait;  /* queue open() when O_EXCL in use */
 166         int sg_tablesize;       /* adapter's max scatter-gather table size */
 167         u32 index;              /* device index number */
 168         Sg_fd *headfp;          /* first open fd belonging to this device */
 169         volatile char detached; /* 0->attached, 1->detached pending removal */
 170         volatile char exclude;  /* opened for exclusive access */
 171         char sgdebug;           /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
 172         struct gendisk *disk;
 173         struct cdev * cdev;     /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
 174 } Sg_device;
 175
 176 static int sg_fasync(int fd, struct file *filp, int mode);
 177 /* tasklet or soft irq callback */
 178 static void sg_rq_end_io(struct request *rq, int uptodate);
 179 static int sg_start_req(Sg_request *srp, unsigned char *cmd);
 180 static void sg_finish_rem_req(Sg_request * srp);
 181 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
 182 static int sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp,
 183                          int tablesize);
 184 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
 185                            Sg_request * srp);
 186 static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
 187                         const char __user *buf, size_t count, int blocking,
 188                         int read_only, Sg_request **o_srp);
 189 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
 190                            unsigned char *cmnd, int timeout, int blocking);
 191 static int sg_read_xfer(Sg_request * srp);
 192 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
 193 static void sg_remove_scat(Sg_scatter_hold * schp);
 194 static void sg_build_reserve(Sg_fd * sfp, int req_size);
 195 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
 196 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
 197 static Sg_fd *sg_add_sfp(Sg_device * sdp, int dev);
 198 static int sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
 199 static void __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
 200 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
 201 static Sg_request *sg_add_request(Sg_fd * sfp);
 202 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
 203 static int sg_res_in_use(Sg_fd * sfp);
 204 static Sg_device *sg_get_dev(int dev);
 205 #ifdef CONFIG_SCSI_PROC_FS
 206 static int sg_last_dev(void);
 207 #endif
 208
 209 #define SZ_SG_HEADER sizeof(struct sg_header)
 210 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
 211 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
 212 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
 213
 214 static int sg_allow_access(struct file *filp, unsigned char *cmd)
 215 {
 216         struct sg_fd *sfp = (struct sg_fd *)filp->private_data;
 217         struct request_queue *q = sfp->parentdp->device->request_queue;
 218
 219         if (sfp->parentdp->device->type == TYPE_SCANNER)
 220                 return 0;
 221
 222         return blk_verify_command(&q->cmd_filter,
 223                                   cmd, filp->f_mode & FMODE_WRITE);
 224 }
 225
 226 static int
 227 sg_open(struct inode *inode, struct file *filp)
 228 {
 229         int dev = iminor(inode);
 230         int flags = filp->f_flags;
 231         struct request_queue *q;
 232         Sg_device *sdp;
 233         Sg_fd *sfp;
 234         int res;
 235         int retval;
 236
 237         lock_kernel();
 238         nonseekable_open(inode, filp);
 239         SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags));
 240         sdp = sg_get_dev(dev);
 241         if ((!sdp) || (!sdp->device)) {
 242                 unlock_kernel();
 243                 return -ENXIO;
 244         }
 245         if (sdp->detached) {
 246                 unlock_kernel();
 247                 return -ENODEV;
 248         }
 249
 250         /* This driver's module count bumped by fops_get in <linux/fs.h> */
 251         /* Prevent the device driver from vanishing while we sleep */
 252         retval = scsi_device_get(sdp->device);
 253         if (retval) {
 254                 unlock_kernel();
 255                 return retval;
 256         }
 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                 retval = -ENOMEM;
 310                 goto error_out;
 311         }
 312         unlock_kernel();
 313         return 0;
 314
 315       error_out:
 316         scsi_device_put(sdp->device);
 317         unlock_kernel();
 318         return retval;
 319 }
 320
 321 /* Following function was formerly called 'sg_close' */
 322 static int
 323 sg_release(struct inode *inode, struct file *filp)
 324 {
 325         Sg_device *sdp;
 326         Sg_fd *sfp;
 327
 328         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 329                 return -ENXIO;
 330         SCSI_LOG_TIMEOUT(3, printk("sg_release: %s\n", sdp->disk->disk_name));
 331         sg_fasync(-1, filp, 0); /* remove filp from async notification list */
 332         if (0 == sg_remove_sfp(sdp, sfp)) {     /* Returns 1 when sdp gone */
 333                 if (!sdp->detached) {
 334                         scsi_device_put(sdp->device);
 335                 }
 336                 sdp->exclude = 0;
 337                 wake_up_interruptible(&sdp->o_excl_wait);
 338         }
 339         return 0;
 340 }
 341
 342 static ssize_t
 343 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
 344 {
 345         Sg_device *sdp;
 346         Sg_fd *sfp;
 347         Sg_request *srp;
 348         int req_pack_id = -1;
 349         sg_io_hdr_t *hp;
 350         struct sg_header *old_hdr = NULL;
 351         int retval = 0;
 352
 353         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 354                 return -ENXIO;
 355         SCSI_LOG_TIMEOUT(3, printk("sg_read: %s, count=%d\n",
 356                                    sdp->disk->disk_name, (int) count));
 357
 358         if (!access_ok(VERIFY_WRITE, buf, count))
 359                 return -EFAULT;
 360         if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
 361                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 362                 if (!old_hdr)
 363                         return -ENOMEM;
 364                 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
 365                         retval = -EFAULT;
 366                         goto free_old_hdr;
 367                 }
 368                 if (old_hdr->reply_len < 0) {
 369                         if (count >= SZ_SG_IO_HDR) {
 370                                 sg_io_hdr_t *new_hdr;
 371                                 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
 372                                 if (!new_hdr) {
 373                                         retval = -ENOMEM;
 374                                         goto free_old_hdr;
 375                                 }
 376                                 retval =__copy_from_user
 377                                     (new_hdr, buf, SZ_SG_IO_HDR);
 378                                 req_pack_id = new_hdr->pack_id;
 379                                 kfree(new_hdr);
 380                                 if (retval) {
 381                                         retval = -EFAULT;
 382                                         goto free_old_hdr;
 383                                 }
 384                         }
 385                 } else
 386                         req_pack_id = old_hdr->pack_id;
 387         }
 388         srp = sg_get_rq_mark(sfp, req_pack_id);
 389         if (!srp) {             /* now wait on packet to arrive */
 390                 if (sdp->detached) {
 391                         retval = -ENODEV;
 392                         goto free_old_hdr;
 393                 }
 394                 if (filp->f_flags & O_NONBLOCK) {
 395                         retval = -EAGAIN;
 396                         goto free_old_hdr;
 397                 }
 398                 while (1) {
 399                         retval = 0; /* following macro beats race condition */
 400                         __wait_event_interruptible(sfp->read_wait,
 401                                 (sdp->detached ||
 402                                 (srp = sg_get_rq_mark(sfp, req_pack_id))),
 403                                 retval);
 404                         if (sdp->detached) {
 405                                 retval = -ENODEV;
 406                                 goto free_old_hdr;
 407                         }
 408                         if (0 == retval)
 409                                 break;
 410
 411                         /* -ERESTARTSYS as signal hit process */
 412                         goto free_old_hdr;
 413                 }
 414         }
 415         if (srp->header.interface_id != '\0') {
 416                 retval = sg_new_read(sfp, buf, count, srp);
 417                 goto free_old_hdr;
 418         }
 419
 420         hp = &srp->header;
 421         if (old_hdr == NULL) {
 422                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 423                 if (! old_hdr) {
 424                         retval = -ENOMEM;
 425                         goto free_old_hdr;
 426                 }
 427         }
 428         memset(old_hdr, 0, SZ_SG_HEADER);
 429         old_hdr->reply_len = (int) hp->timeout;
 430         old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
 431         old_hdr->pack_id = hp->pack_id;
 432         old_hdr->twelve_byte =
 433             ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
 434         old_hdr->target_status = hp->masked_status;
 435         old_hdr->host_status = hp->host_status;
 436         old_hdr->driver_status = hp->driver_status;
 437         if ((CHECK_CONDITION & hp->masked_status) ||
 438             (DRIVER_SENSE & hp->driver_status))
 439                 memcpy(old_hdr->sense_buffer, srp->sense_b,
 440                        sizeof (old_hdr->sense_buffer));
 441         switch (hp->host_status) {
 442         /* This setup of 'result' is for backward compatibility and is best
 443            ignored by the user who should use target, host + driver status */
 444         case DID_OK:
 445         case DID_PASSTHROUGH:
 446         case DID_SOFT_ERROR:
 447                 old_hdr->result = 0;
 448                 break;
 449         case DID_NO_CONNECT:
 450         case DID_BUS_BUSY:
 451         case DID_TIME_OUT:
 452                 old_hdr->result = EBUSY;
 453                 break;
 454         case DID_BAD_TARGET:
 455         case DID_ABORT:
 456         case DID_PARITY:
 457         case DID_RESET:
 458         case DID_BAD_INTR:
 459                 old_hdr->result = EIO;
 460                 break;
 461         case DID_ERROR:
 462                 old_hdr->result = (srp->sense_b[0] == 0 &&
 463                                   hp->masked_status == GOOD) ? 0 : EIO;
 464                 break;
 465         default:
 466                 old_hdr->result = EIO;
 467                 break;
 468         }
 469
 470         /* Now copy the result back to the user buffer.  */
 471         if (count >= SZ_SG_HEADER) {
 472                 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
 473                         retval = -EFAULT;
 474                         goto free_old_hdr;
 475                 }
 476                 buf += SZ_SG_HEADER;
 477                 if (count > old_hdr->reply_len)
 478                         count = old_hdr->reply_len;
 479                 if (count > SZ_SG_HEADER) {
 480                         if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
 481                                 retval = -EFAULT;
 482                                 goto free_old_hdr;
 483                         }
 484                 }
 485         } else
 486                 count = (old_hdr->result == 0) ? 0 : -EIO;
 487         sg_finish_rem_req(srp);
 488         retval = count;
 489 free_old_hdr:
 490         kfree(old_hdr);
 491         return retval;
 492 }
 493
 494 static ssize_t
 495 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
 496 {
 497         sg_io_hdr_t *hp = &srp->header;
 498         int err = 0;
 499         int len;
 500
 501         if (count < SZ_SG_IO_HDR) {
 502                 err = -EINVAL;
 503                 goto err_out;
 504         }
 505         hp->sb_len_wr = 0;
 506         if ((hp->mx_sb_len > 0) && hp->sbp) {
 507                 if ((CHECK_CONDITION & hp->masked_status) ||
 508                     (DRIVER_SENSE & hp->driver_status)) {
 509                         int sb_len = SCSI_SENSE_BUFFERSIZE;
 510                         sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
 511                         len = 8 + (int) srp->sense_b[7];        /* Additional sense length field */
 512                         len = (len > sb_len) ? sb_len : len;
 513                         if (copy_to_user(hp->sbp, srp->sense_b, len)) {
 514                                 err = -EFAULT;
 515                                 goto err_out;
 516                         }
 517                         hp->sb_len_wr = len;
 518                 }
 519         }
 520         if (hp->masked_status || hp->host_status || hp->driver_status)
 521                 hp->info |= SG_INFO_CHECK;
 522         if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
 523                 err = -EFAULT;
 524                 goto err_out;
 525         }
 526         err = sg_read_xfer(srp);
 527       err_out:
 528         sg_finish_rem_req(srp);
 529         return (0 == err) ? count : err;
 530 }
 531
 532 static ssize_t
 533 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
 534 {
 535         int mxsize, cmd_size, k;
 536         int input_size, blocking;
 537         unsigned char opcode;
 538         Sg_device *sdp;
 539         Sg_fd *sfp;
 540         Sg_request *srp;
 541         struct sg_header old_hdr;
 542         sg_io_hdr_t *hp;
 543         unsigned char cmnd[MAX_COMMAND_SIZE];
 544
 545         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 546                 return -ENXIO;
 547         SCSI_LOG_TIMEOUT(3, printk("sg_write: %s, count=%d\n",
 548                                    sdp->disk->disk_name, (int) count));
 549         if (sdp->detached)
 550                 return -ENODEV;
 551         if (!((filp->f_flags & O_NONBLOCK) ||
 552               scsi_block_when_processing_errors(sdp->device)))
 553                 return -ENXIO;
 554
 555         if (!access_ok(VERIFY_READ, buf, count))
 556                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 557         if (count < SZ_SG_HEADER)
 558                 return -EIO;
 559         if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
 560                 return -EFAULT;
 561         blocking = !(filp->f_flags & O_NONBLOCK);
 562         if (old_hdr.reply_len < 0)
 563                 return sg_new_write(sfp, filp, buf, count, blocking, 0, NULL);
 564         if (count < (SZ_SG_HEADER + 6))
 565                 return -EIO;    /* The minimum scsi command length is 6 bytes. */
 566
 567         if (!(srp = sg_add_request(sfp))) {
 568                 SCSI_LOG_TIMEOUT(1, printk("sg_write: queue full\n"));
 569                 return -EDOM;
 570         }
 571         buf += SZ_SG_HEADER;
 572         __get_user(opcode, buf);
 573         if (sfp->next_cmd_len > 0) {
 574                 if (sfp->next_cmd_len > MAX_COMMAND_SIZE) {
 575                         SCSI_LOG_TIMEOUT(1, printk("sg_write: command length too long\n"));
 576                         sfp->next_cmd_len = 0;
 577                         sg_remove_request(sfp, srp);
 578                         return -EIO;
 579                 }
 580                 cmd_size = sfp->next_cmd_len;
 581                 sfp->next_cmd_len = 0;  /* reset so only this write() effected */
 582         } else {
 583                 cmd_size = COMMAND_SIZE(opcode);        /* based on SCSI command group */
 584                 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
 585                         cmd_size = 12;
 586         }
 587         SCSI_LOG_TIMEOUT(4, printk(
 588                 "sg_write:   scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
 589 /* Determine buffer size.  */
 590         input_size = count - cmd_size;
 591         mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
 592         mxsize -= SZ_SG_HEADER;
 593         input_size -= SZ_SG_HEADER;
 594         if (input_size < 0) {
 595                 sg_remove_request(sfp, srp);
 596                 return -EIO;    /* User did not pass enough bytes for this command. */
 597         }
 598         hp = &srp->header;
 599         hp->interface_id = '\0';        /* indicator of old interface tunnelled */
 600         hp->cmd_len = (unsigned char) cmd_size;
 601         hp->iovec_count = 0;
 602         hp->mx_sb_len = 0;
 603         if (input_size > 0)
 604                 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
 605                     SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
 606         else
 607                 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
 608         hp->dxfer_len = mxsize;
 609         if (hp->dxfer_direction == SG_DXFER_TO_DEV)
 610                 hp->dxferp = (char __user *)buf + cmd_size;
 611         else
 612                 hp->dxferp = NULL;
 613         hp->sbp = NULL;
 614         hp->timeout = old_hdr.reply_len;        /* structure abuse ... */
 615         hp->flags = input_size; /* structure abuse ... */
 616         hp->pack_id = old_hdr.pack_id;
 617         hp->usr_ptr = NULL;
 618         if (__copy_from_user(cmnd, buf, cmd_size))
 619                 return -EFAULT;
 620         /*
 621          * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
 622          * but is is possible that the app intended SG_DXFER_TO_DEV, because there
 623          * is a non-zero input_size, so emit a warning.
 624          */
 625         if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
 626                 static char cmd[TASK_COMM_LEN];
 627                 if (strcmp(current->comm, cmd) && printk_ratelimit()) {
 628                         printk(KERN_WARNING
 629                                "sg_write: data in/out %d/%d bytes for SCSI command 0x%x--"
 630                                "guessing data in;\n" KERN_WARNING "   "
 631                                "program %s not setting count and/or reply_len properly\n",
 632                                old_hdr.reply_len - (int)SZ_SG_HEADER,
 633                                input_size, (unsigned int) cmnd[0],
 634                                current->comm);
 635                         strcpy(cmd, current->comm);
 636                 }
 637         }
 638         k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
 639         return (k < 0) ? k : count;
 640 }
 641
 642 static ssize_t
 643 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
 644                  size_t count, int blocking, int read_only,
 645                  Sg_request **o_srp)
 646 {
 647         int k;
 648         Sg_request *srp;
 649         sg_io_hdr_t *hp;
 650         unsigned char cmnd[MAX_COMMAND_SIZE];
 651         int timeout;
 652         unsigned long ul_timeout;
 653
 654         if (count < SZ_SG_IO_HDR)
 655                 return -EINVAL;
 656         if (!access_ok(VERIFY_READ, buf, count))
 657                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 658
 659         sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
 660         if (!(srp = sg_add_request(sfp))) {
 661                 SCSI_LOG_TIMEOUT(1, printk("sg_new_write: queue full\n"));
 662                 return -EDOM;
 663         }
 664         hp = &srp->header;
 665         if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
 666                 sg_remove_request(sfp, srp);
 667                 return -EFAULT;
 668         }
 669         if (hp->interface_id != 'S') {
 670                 sg_remove_request(sfp, srp);
 671                 return -ENOSYS;
 672         }
 673         if (hp->flags & SG_FLAG_MMAP_IO) {
 674                 if (hp->dxfer_len > sfp->reserve.bufflen) {
 675                         sg_remove_request(sfp, srp);
 676                         return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
 677                 }
 678                 if (hp->flags & SG_FLAG_DIRECT_IO) {
 679                         sg_remove_request(sfp, srp);
 680                         return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
 681                 }
 682                 if (sg_res_in_use(sfp)) {
 683                         sg_remove_request(sfp, srp);
 684                         return -EBUSY;  /* reserve buffer already being used */
 685                 }
 686         }
 687         ul_timeout = msecs_to_jiffies(srp->header.timeout);
 688         timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
 689         if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
 690                 sg_remove_request(sfp, srp);
 691                 return -EMSGSIZE;
 692         }
 693         if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
 694                 sg_remove_request(sfp, srp);
 695                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 696         }
 697         if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
 698                 sg_remove_request(sfp, srp);
 699                 return -EFAULT;
 700         }
 701         if (read_only && sg_allow_access(file, cmnd)) {
 702                 sg_remove_request(sfp, srp);
 703                 return -EPERM;
 704         }
 705         k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
 706         if (k < 0)
 707                 return k;
 708         if (o_srp)
 709                 *o_srp = srp;
 710         return count;
 711 }
 712
 713 static int
 714 sg_common_write(Sg_fd * sfp, Sg_request * srp,
 715                 unsigned char *cmnd, int timeout, int blocking)
 716 {
 717         int k, data_dir;
 718         Sg_device *sdp = sfp->parentdp;
 719         sg_io_hdr_t *hp = &srp->header;
 720
 721         srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
 722         hp->status = 0;
 723         hp->masked_status = 0;
 724         hp->msg_status = 0;
 725         hp->info = 0;
 726         hp->host_status = 0;
 727         hp->driver_status = 0;
 728         hp->resid = 0;
 729         SCSI_LOG_TIMEOUT(4, printk("sg_common_write:  scsi opcode=0x%02x, cmd_size=%d\n",
 730                           (int) cmnd[0], (int) hp->cmd_len));
 731
 732         k = sg_start_req(srp, cmnd);
 733         if (k) {
 734                 SCSI_LOG_TIMEOUT(1, printk("sg_common_write: start_req err=%d\n", k));
 735                 sg_finish_rem_req(srp);
 736                 return k;       /* probably out of space --> ENOMEM */
 737         }
 738         if (sdp->detached) {
 739                 sg_finish_rem_req(srp);
 740                 return -ENODEV;
 741         }
 742
 743         switch (hp->dxfer_direction) {
 744         case SG_DXFER_TO_FROM_DEV:
 745         case SG_DXFER_FROM_DEV:
 746                 data_dir = DMA_FROM_DEVICE;
 747                 break;
 748         case SG_DXFER_TO_DEV:
 749                 data_dir = DMA_TO_DEVICE;
 750                 break;
 751         case SG_DXFER_UNKNOWN:
 752                 data_dir = DMA_BIDIRECTIONAL;
 753                 break;
 754         default:
 755                 data_dir = DMA_NONE;
 756                 break;
 757         }
 758         hp->duration = jiffies_to_msecs(jiffies);
 759
 760         srp->rq->timeout = timeout;
 761         blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk,
 762                               srp->rq, 1, sg_rq_end_io);
 763         return 0;
 764 }
 765
 766 static int
 767 sg_srp_done(Sg_request *srp, Sg_fd *sfp)
 768 {
 769         unsigned long iflags;
 770         int done;
 771
 772         read_lock_irqsave(&sfp->rq_list_lock, iflags);
 773         done = srp->done;
 774         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 775         return done;
 776 }
 777
 778 static int
 779 sg_ioctl(struct inode *inode, struct file *filp,
 780          unsigned int cmd_in, unsigned long arg)
 781 {
 782         void __user *p = (void __user *)arg;
 783         int __user *ip = p;
 784         int result, val, read_only;
 785         Sg_device *sdp;
 786         Sg_fd *sfp;
 787         Sg_request *srp;
 788         unsigned long iflags;
 789
 790         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 791                 return -ENXIO;
 792
 793         SCSI_LOG_TIMEOUT(3, printk("sg_ioctl: %s, cmd=0x%x\n",
 794                                    sdp->disk->disk_name, (int) cmd_in));
 795         read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
 796
 797         switch (cmd_in) {
 798         case SG_IO:
 799                 {
 800                         int blocking = 1;       /* ignore O_NONBLOCK flag */
 801
 802                         if (sdp->detached)
 803                                 return -ENODEV;
 804                         if (!scsi_block_when_processing_errors(sdp->device))
 805                                 return -ENXIO;
 806                         if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
 807                                 return -EFAULT;
 808                         result =
 809                             sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
 810                                          blocking, read_only, &srp);
 811                         if (result < 0)
 812                                 return result;
 813                         srp->sg_io_owned = 1;
 814                         while (1) {
 815                                 result = 0;     /* following macro to beat race condition */
 816                                 __wait_event_interruptible(sfp->read_wait,
 817                                         (sdp->detached || sfp->closed || sg_srp_done(srp, sfp)),
 818                                                            result);
 819                                 if (sdp->detached)
 820                                         return -ENODEV;
 821                                 if (sfp->closed)
 822                                         return 0;       /* request packet dropped already */
 823                                 if (0 == result)
 824                                         break;
 825                                 srp->orphan = 1;
 826                                 return result;  /* -ERESTARTSYS because signal hit process */
 827                         }
 828                         write_lock_irqsave(&sfp->rq_list_lock, iflags);
 829                         srp->done = 2;
 830                         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 831                         result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
 832                         return (result < 0) ? result : 0;
 833                 }
 834         case SG_SET_TIMEOUT:
 835                 result = get_user(val, ip);
 836                 if (result)
 837                         return result;
 838                 if (val < 0)
 839                         return -EIO;
 840                 if (val >= MULDIV (INT_MAX, USER_HZ, HZ))
 841                     val = MULDIV (INT_MAX, USER_HZ, HZ);
 842                 sfp->timeout_user = val;
 843                 sfp->timeout = MULDIV (val, HZ, USER_HZ);
 844
 845                 return 0;
 846         case SG_GET_TIMEOUT:    /* N.B. User receives timeout as return value */
 847                                 /* strange ..., for backward compatibility */
 848                 return sfp->timeout_user;
 849         case SG_SET_FORCE_LOW_DMA:
 850                 result = get_user(val, ip);
 851                 if (result)
 852                         return result;
 853                 if (val) {
 854                         sfp->low_dma = 1;
 855                         if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
 856                                 val = (int) sfp->reserve.bufflen;
 857                                 sg_remove_scat(&sfp->reserve);
 858                                 sg_build_reserve(sfp, val);
 859                         }
 860                 } else {
 861                         if (sdp->detached)
 862                                 return -ENODEV;
 863                         sfp->low_dma = sdp->device->host->unchecked_isa_dma;
 864                 }
 865                 return 0;
 866         case SG_GET_LOW_DMA:
 867                 return put_user((int) sfp->low_dma, ip);
 868         case SG_GET_SCSI_ID:
 869                 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
 870                         return -EFAULT;
 871                 else {
 872                         sg_scsi_id_t __user *sg_idp = p;
 873
 874                         if (sdp->detached)
 875                                 return -ENODEV;
 876                         __put_user((int) sdp->device->host->host_no,
 877                                    &sg_idp->host_no);
 878                         __put_user((int) sdp->device->channel,
 879                                    &sg_idp->channel);
 880                         __put_user((int) sdp->device->id, &sg_idp->scsi_id);
 881                         __put_user((int) sdp->device->lun, &sg_idp->lun);
 882                         __put_user((int) sdp->device->type, &sg_idp->scsi_type);
 883                         __put_user((short) sdp->device->host->cmd_per_lun,
 884                                    &sg_idp->h_cmd_per_lun);
 885                         __put_user((short) sdp->device->queue_depth,
 886                                    &sg_idp->d_queue_depth);
 887                         __put_user(0, &sg_idp->unused[0]);
 888                         __put_user(0, &sg_idp->unused[1]);
 889                         return 0;
 890                 }
 891         case SG_SET_FORCE_PACK_ID:
 892                 result = get_user(val, ip);
 893                 if (result)
 894                         return result;
 895                 sfp->force_packid = val ? 1 : 0;
 896                 return 0;
 897         case SG_GET_PACK_ID:
 898                 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
 899                         return -EFAULT;
 900                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 901                 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
 902                         if ((1 == srp->done) && (!srp->sg_io_owned)) {
 903                                 read_unlock_irqrestore(&sfp->rq_list_lock,
 904                                                        iflags);
 905                                 __put_user(srp->header.pack_id, ip);
 906                                 return 0;
 907                         }
 908                 }
 909                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 910                 __put_user(-1, ip);
 911                 return 0;
 912         case SG_GET_NUM_WAITING:
 913                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 914                 for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) {
 915                         if ((1 == srp->done) && (!srp->sg_io_owned))
 916                                 ++val;
 917                 }
 918                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 919                 return put_user(val, ip);
 920         case SG_GET_SG_TABLESIZE:
 921                 return put_user(sdp->sg_tablesize, ip);
 922         case SG_SET_RESERVED_SIZE:
 923                 result = get_user(val, ip);
 924                 if (result)
 925                         return result;
 926                 if (val < 0)
 927                         return -EINVAL;
 928                 val = min_t(int, val,
 929                                 sdp->device->request_queue->max_sectors * 512);
 930                 if (val != sfp->reserve.bufflen) {
 931                         if (sg_res_in_use(sfp) || sfp->mmap_called)
 932                                 return -EBUSY;
 933                         sg_remove_scat(&sfp->reserve);
 934                         sg_build_reserve(sfp, val);
 935                 }
 936                 return 0;
 937         case SG_GET_RESERVED_SIZE:
 938                 val = min_t(int, sfp->reserve.bufflen,
 939                                 sdp->device->request_queue->max_sectors * 512);
 940                 return put_user(val, ip);
 941         case SG_SET_COMMAND_Q:
 942                 result = get_user(val, ip);
 943                 if (result)
 944                         return result;
 945                 sfp->cmd_q = val ? 1 : 0;
 946                 return 0;
 947         case SG_GET_COMMAND_Q:
 948                 return put_user((int) sfp->cmd_q, ip);
 949         case SG_SET_KEEP_ORPHAN:
 950                 result = get_user(val, ip);
 951                 if (result)
 952                         return result;
 953                 sfp->keep_orphan = val;
 954                 return 0;
 955         case SG_GET_KEEP_ORPHAN:
 956                 return put_user((int) sfp->keep_orphan, ip);
 957         case SG_NEXT_CMD_LEN:
 958                 result = get_user(val, ip);
 959                 if (result)
 960                         return result;
 961                 sfp->next_cmd_len = (val > 0) ? val : 0;
 962                 return 0;
 963         case SG_GET_VERSION_NUM:
 964                 return put_user(sg_version_num, ip);
 965         case SG_GET_ACCESS_COUNT:
 966                 /* faked - we don't have a real access count anymore */
 967                 val = (sdp->device ? 1 : 0);
 968                 return put_user(val, ip);
 969         case SG_GET_REQUEST_TABLE:
 970                 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
 971                         return -EFAULT;
 972                 else {
 973                         sg_req_info_t *rinfo;
 974                         unsigned int ms;
 975
 976                         rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
 977                                                                 GFP_KERNEL);
 978                         if (!rinfo)
 979                                 return -ENOMEM;
 980                         read_lock_irqsave(&sfp->rq_list_lock, iflags);
 981                         for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE;
 982                              ++val, srp = srp ? srp->nextrp : srp) {
 983                                 memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
 984                                 if (srp) {
 985                                         rinfo[val].req_state = srp->done + 1;
 986                                         rinfo[val].problem =
 987                                             srp->header.masked_status &
 988                                             srp->header.host_status &
 989                                             srp->header.driver_status;
 990                                         if (srp->done)
 991                                                 rinfo[val].duration =
 992                                                         srp->header.duration;
 993                                         else {
 994                                                 ms = jiffies_to_msecs(jiffies);
 995                                                 rinfo[val].duration =
 996                                                     (ms > srp->header.duration) ?
 997                                                     (ms - srp->header.duration) : 0;
 998                                         }
 999                                         rinfo[val].orphan = srp->orphan;
1000                                         rinfo[val].sg_io_owned =
1001                                                         srp->sg_io_owned;
1002                                         rinfo[val].pack_id =
1003                                                         srp->header.pack_id;
1004                                         rinfo[val].usr_ptr =
1005                                                         srp->header.usr_ptr;
1006                                 }
1007                         }
1008                         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1009                         result = __copy_to_user(p, rinfo,
1010                                                 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1011                         result = result ? -EFAULT : 0;
1012                         kfree(rinfo);
1013                         return result;
1014                 }
1015         case SG_EMULATED_HOST:
1016                 if (sdp->detached)
1017                         return -ENODEV;
1018                 return put_user(sdp->device->host->hostt->emulated, ip);
1019         case SG_SCSI_RESET:
1020                 if (sdp->detached)
1021                         return -ENODEV;
1022                 if (filp->f_flags & O_NONBLOCK) {
1023                         if (scsi_host_in_recovery(sdp->device->host))
1024                                 return -EBUSY;
1025                 } else if (!scsi_block_when_processing_errors(sdp->device))
1026                         return -EBUSY;
1027                 result = get_user(val, ip);
1028                 if (result)
1029                         return result;
1030                 if (SG_SCSI_RESET_NOTHING == val)
1031                         return 0;
1032                 switch (val) {
1033                 case SG_SCSI_RESET_DEVICE:
1034                         val = SCSI_TRY_RESET_DEVICE;
1035                         break;
1036                 case SG_SCSI_RESET_TARGET:
1037                         val = SCSI_TRY_RESET_TARGET;
1038                         break;
1039                 case SG_SCSI_RESET_BUS:
1040                         val = SCSI_TRY_RESET_BUS;
1041                         break;
1042                 case SG_SCSI_RESET_HOST:
1043                         val = SCSI_TRY_RESET_HOST;
1044                         break;
1045                 default:
1046                         return -EINVAL;
1047                 }
1048                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1049                         return -EACCES;
1050                 return (scsi_reset_provider(sdp->device, val) ==
1051                         SUCCESS) ? 0 : -EIO;
1052         case SCSI_IOCTL_SEND_COMMAND:
1053                 if (sdp->detached)
1054                         return -ENODEV;
1055                 if (read_only) {
1056                         unsigned char opcode = WRITE_6;
1057                         Scsi_Ioctl_Command __user *siocp = p;
1058
1059                         if (copy_from_user(&opcode, siocp->data, 1))
1060                                 return -EFAULT;
1061                         if (sg_allow_access(filp, &opcode))
1062                                 return -EPERM;
1063                 }
1064                 return sg_scsi_ioctl(filp, sdp->device->request_queue, NULL, p);
1065         case SG_SET_DEBUG:
1066                 result = get_user(val, ip);
1067                 if (result)
1068                         return result;
1069                 sdp->sgdebug = (char) val;
1070                 return 0;
1071         case SCSI_IOCTL_GET_IDLUN:
1072         case SCSI_IOCTL_GET_BUS_NUMBER:
1073         case SCSI_IOCTL_PROBE_HOST:
1074         case SG_GET_TRANSFORM:
1075                 if (sdp->detached)
1076                         return -ENODEV;
1077                 return scsi_ioctl(sdp->device, cmd_in, p);
1078         case BLKSECTGET:
1079                 return put_user(sdp->device->request_queue->max_sectors * 512,
1080                                 ip);
1081         case BLKTRACESETUP:
1082                 return blk_trace_setup(sdp->device->request_queue,
1083                                        sdp->disk->disk_name,
1084                                        sdp->device->sdev_gendev.devt,
1085                                        (char *)arg);
1086         case BLKTRACESTART:
1087                 return blk_trace_startstop(sdp->device->request_queue, 1);
1088         case BLKTRACESTOP:
1089                 return blk_trace_startstop(sdp->device->request_queue, 0);
1090         case BLKTRACETEARDOWN:
1091                 return blk_trace_remove(sdp->device->request_queue);
1092         default:
1093                 if (read_only)
1094                         return -EPERM;  /* don't know so take safe approach */
1095                 return scsi_ioctl(sdp->device, cmd_in, p);
1096         }
1097 }
1098
1099 #ifdef CONFIG_COMPAT
1100 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1101 {
1102         Sg_device *sdp;
1103         Sg_fd *sfp;
1104         struct scsi_device *sdev;
1105
1106         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1107                 return -ENXIO;
1108
1109         sdev = sdp->device;
1110         if (sdev->host->hostt->compat_ioctl) {
1111                 int ret;
1112
1113                 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1114
1115                 return ret;
1116         }
1117
1118         return -ENOIOCTLCMD;
1119 }
1120 #endif
1121
1122 static unsigned int
1123 sg_poll(struct file *filp, poll_table * wait)
1124 {
1125         unsigned int res = 0;
1126         Sg_device *sdp;
1127         Sg_fd *sfp;
1128         Sg_request *srp;
1129         int count = 0;
1130         unsigned long iflags;
1131
1132         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))
1133             || sfp->closed)
1134                 return POLLERR;
1135         poll_wait(filp, &sfp->read_wait, wait);
1136         read_lock_irqsave(&sfp->rq_list_lock, iflags);
1137         for (srp = sfp->headrp; srp; srp = srp->nextrp) {
1138                 /* if any read waiting, flag it */
1139                 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1140                         res = POLLIN | POLLRDNORM;
1141                 ++count;
1142         }
1143         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1144
1145         if (sdp->detached)
1146                 res |= POLLHUP;
1147         else if (!sfp->cmd_q) {
1148                 if (0 == count)
1149                         res |= POLLOUT | POLLWRNORM;
1150         } else if (count < SG_MAX_QUEUE)
1151                 res |= POLLOUT | POLLWRNORM;
1152         SCSI_LOG_TIMEOUT(3, printk("sg_poll: %s, res=0x%x\n",
1153                                    sdp->disk->disk_name, (int) res));
1154         return res;
1155 }
1156
1157 static int
1158 sg_fasync(int fd, struct file *filp, int mode)
1159 {
1160         int retval;
1161         Sg_device *sdp;
1162         Sg_fd *sfp;
1163
1164         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1165                 return -ENXIO;
1166         SCSI_LOG_TIMEOUT(3, printk("sg_fasync: %s, mode=%d\n",
1167                                    sdp->disk->disk_name, mode));
1168
1169         retval = fasync_helper(fd, filp, mode, &sfp->async_qp);
1170         return (retval < 0) ? retval : 0;
1171 }
1172
1173 static int
1174 sg_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1175 {
1176         Sg_fd *sfp;
1177         unsigned long offset, len, sa;
1178         Sg_scatter_hold *rsv_schp;
1179         int k, length;
1180
1181         if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1182                 return VM_FAULT_SIGBUS;
1183         rsv_schp = &sfp->reserve;
1184         offset = vmf->pgoff << PAGE_SHIFT;
1185         if (offset >= rsv_schp->bufflen)
1186                 return VM_FAULT_SIGBUS;
1187         SCSI_LOG_TIMEOUT(3, printk("sg_vma_fault: offset=%lu, scatg=%d\n",
1188                                    offset, rsv_schp->k_use_sg));
1189         sa = vma->vm_start;
1190         length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1191         for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1192                 len = vma->vm_end - sa;
1193                 len = (len < length) ? len : length;
1194                 if (offset < len) {
1195                         struct page *page = nth_page(rsv_schp->pages[k],
1196                                                      offset >> PAGE_SHIFT);
1197                         get_page(page); /* increment page count */
1198                         vmf->page = page;
1199                         return 0; /* success */
1200                 }
1201                 sa += len;
1202                 offset -= len;
1203         }
1204
1205         return VM_FAULT_SIGBUS;
1206 }
1207
1208 static struct vm_operations_struct sg_mmap_vm_ops = {
1209         .fault = sg_vma_fault,
1210 };
1211
1212 static int
1213 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1214 {
1215         Sg_fd *sfp;
1216         unsigned long req_sz, len, sa;
1217         Sg_scatter_hold *rsv_schp;
1218         int k, length;
1219
1220         if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1221                 return -ENXIO;
1222         req_sz = vma->vm_end - vma->vm_start;
1223         SCSI_LOG_TIMEOUT(3, printk("sg_mmap starting, vm_start=%p, len=%d\n",
1224                                    (void *) vma->vm_start, (int) req_sz));
1225         if (vma->vm_pgoff)
1226                 return -EINVAL; /* want no offset */
1227         rsv_schp = &sfp->reserve;
1228         if (req_sz > rsv_schp->bufflen)
1229                 return -ENOMEM; /* cannot map more than reserved buffer */
1230
1231         sa = vma->vm_start;
1232         length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1233         for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1234                 len = vma->vm_end - sa;
1235                 len = (len < length) ? len : length;
1236                 sa += len;
1237         }
1238
1239         sfp->mmap_called = 1;
1240         vma->vm_flags |= VM_RESERVED;
1241         vma->vm_private_data = sfp;
1242         vma->vm_ops = &sg_mmap_vm_ops;
1243         return 0;
1244 }
1245
1246 /*
1247  * This function is a "bottom half" handler that is called by the mid
1248  * level when a command is completed (or has failed).
1249  */
1250 static void sg_rq_end_io(struct request *rq, int uptodate)
1251 {
1252         struct sg_request *srp = rq->end_io_data;
1253         Sg_device *sdp = NULL;
1254         Sg_fd *sfp;
1255         unsigned long iflags;
1256         unsigned int ms;
1257         char *sense;
1258         int result, resid;
1259
1260         if (NULL == srp) {
1261                 printk(KERN_ERR "sg_cmd_done: NULL request\n");
1262                 return;
1263         }
1264         sfp = srp->parentfp;
1265         if (sfp)
1266                 sdp = sfp->parentdp;
1267         if ((NULL == sdp) || sdp->detached) {
1268                 printk(KERN_INFO "sg_cmd_done: device detached\n");
1269                 return;
1270         }
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         if (sfp->closed) {      /* whoops this fd already released, cleanup */
1310                 SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, freeing ...\n"));
1311                 sg_finish_rem_req(srp);
1312                 srp = NULL;
1313                 if (NULL == sfp->headrp) {
1314                         SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, final cleanup\n"));
1315                         if (0 == sg_remove_sfp(sdp, sfp)) {     /* device still present */
1316                                 scsi_device_put(sdp->device);
1317                         }
1318                         sfp = NULL;
1319                 }
1320         } else if (srp && srp->orphan) {
1321                 if (sfp->keep_orphan)
1322                         srp->sg_io_owned = 0;
1323                 else {
1324                         sg_finish_rem_req(srp);
1325                         srp = NULL;
1326                 }
1327         }
1328         if (sfp && srp) {
1329                 /* Now wake up any sg_read() that is waiting for this packet. */
1330                 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1331                 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1332                 srp->done = 1;
1333                 wake_up_interruptible(&sfp->read_wait);
1334                 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1335         }
1336 }
1337
1338 static struct file_operations sg_fops = {
1339         .owner = THIS_MODULE,
1340         .read = sg_read,
1341         .write = sg_write,
1342         .poll = sg_poll,
1343         .ioctl = sg_ioctl,
1344 #ifdef CONFIG_COMPAT
1345         .compat_ioctl = sg_compat_ioctl,
1346 #endif
1347         .open = sg_open,
1348         .mmap = sg_mmap,
1349         .release = sg_release,
1350         .fasync = sg_fasync,
1351 };
1352
1353 static struct class *sg_sysfs_class;
1354
1355 static int sg_sysfs_valid = 0;
1356
1357 static Sg_device *sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1358 {
1359         struct request_queue *q = scsidp->request_queue;
1360         Sg_device *sdp;
1361         unsigned long iflags;
1362         int error;
1363         u32 k;
1364
1365         sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1366         if (!sdp) {
1367                 printk(KERN_WARNING "kmalloc Sg_device failure\n");
1368                 return ERR_PTR(-ENOMEM);
1369         }
1370         error = -ENOMEM;
1371         if (!idr_pre_get(&sg_index_idr, GFP_KERNEL)) {
1372                 printk(KERN_WARNING "idr expansion Sg_device failure\n");
1373                 goto out;
1374         }
1375
1376         write_lock_irqsave(&sg_index_lock, iflags);
1377         error = idr_get_new(&sg_index_idr, sdp, &k);
1378         write_unlock_irqrestore(&sg_index_lock, iflags);
1379
1380         if (error) {
1381                 printk(KERN_WARNING "idr allocation Sg_device failure: %d\n",
1382                        error);
1383                 goto out;
1384         }
1385
1386         if (unlikely(k >= SG_MAX_DEVS))
1387                 goto overflow;
1388
1389         SCSI_LOG_TIMEOUT(3, printk("sg_alloc: dev=%d \n", k));
1390         sprintf(disk->disk_name, "sg%d", k);
1391         disk->first_minor = k;
1392         sdp->disk = disk;
1393         sdp->device = scsidp;
1394         init_waitqueue_head(&sdp->o_excl_wait);
1395         sdp->sg_tablesize = min(q->max_hw_segments, q->max_phys_segments);
1396         sdp->index = k;
1397
1398         error = 0;
1399  out:
1400         if (error) {
1401                 kfree(sdp);
1402                 return ERR_PTR(error);
1403         }
1404         return sdp;
1405
1406  overflow:
1407         sdev_printk(KERN_WARNING, scsidp,
1408                     "Unable to attach sg device type=%d, minor "
1409                     "number exceeds %d\n", scsidp->type, SG_MAX_DEVS - 1);
1410         error = -ENODEV;
1411         goto out;
1412 }
1413
1414 static int
1415 sg_add(struct device *cl_dev, struct class_interface *cl_intf)
1416 {
1417         struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1418         struct gendisk *disk;
1419         Sg_device *sdp = NULL;
1420         struct cdev * cdev = NULL;
1421         int error;
1422         unsigned long iflags;
1423
1424         disk = alloc_disk(1);
1425         if (!disk) {
1426                 printk(KERN_WARNING "alloc_disk failed\n");
1427                 return -ENOMEM;
1428         }
1429         disk->major = SCSI_GENERIC_MAJOR;
1430
1431         error = -ENOMEM;
1432         cdev = cdev_alloc();
1433         if (!cdev) {
1434                 printk(KERN_WARNING "cdev_alloc failed\n");
1435                 goto out;
1436         }
1437         cdev->owner = THIS_MODULE;
1438         cdev->ops = &sg_fops;
1439
1440         sdp = sg_alloc(disk, scsidp);
1441         if (IS_ERR(sdp)) {
1442                 printk(KERN_WARNING "sg_alloc failed\n");
1443                 error = PTR_ERR(sdp);
1444                 goto out;
1445         }
1446
1447         error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1448         if (error)
1449                 goto cdev_add_err;
1450
1451         sdp->cdev = cdev;
1452         if (sg_sysfs_valid) {
1453                 struct device *sg_class_member;
1454
1455                 sg_class_member = device_create_drvdata(sg_sysfs_class,
1456                                                         cl_dev->parent,
1457                                                         MKDEV(SCSI_GENERIC_MAJOR,
1458                                                               sdp->index),
1459                                                         sdp,
1460                                                         "%s", disk->disk_name);
1461                 if (IS_ERR(sg_class_member)) {
1462                         printk(KERN_ERR "sg_add: "
1463                                "device_create failed\n");
1464                         error = PTR_ERR(sg_class_member);
1465                         goto cdev_add_err;
1466                 }
1467                 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1468                                           &sg_class_member->kobj, "generic");
1469                 if (error)
1470                         printk(KERN_ERR "sg_add: unable to make symlink "
1471                                         "'generic' back to sg%d\n", sdp->index);
1472         } else
1473                 printk(KERN_WARNING "sg_add: sg_sys Invalid\n");
1474
1475         sdev_printk(KERN_NOTICE, scsidp,
1476                     "Attached scsi generic sg%d type %d\n", sdp->index,
1477                     scsidp->type);
1478
1479         dev_set_drvdata(cl_dev, sdp);
1480
1481         return 0;
1482
1483 cdev_add_err:
1484         write_lock_irqsave(&sg_index_lock, iflags);
1485         idr_remove(&sg_index_idr, sdp->index);
1486         write_unlock_irqrestore(&sg_index_lock, iflags);
1487         kfree(sdp);
1488
1489 out:
1490         put_disk(disk);
1491         if (cdev)
1492                 cdev_del(cdev);
1493         return error;
1494 }
1495
1496 static void
1497 sg_remove(struct device *cl_dev, struct class_interface *cl_intf)
1498 {
1499         struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1500         Sg_device *sdp = dev_get_drvdata(cl_dev);
1501         unsigned long iflags;
1502         Sg_fd *sfp;
1503         Sg_fd *tsfp;
1504         Sg_request *srp;
1505         Sg_request *tsrp;
1506         int delay;
1507
1508         if (!sdp)
1509                 return;
1510
1511         delay = 0;
1512         write_lock_irqsave(&sg_index_lock, iflags);
1513         if (sdp->headfp) {
1514                 sdp->detached = 1;
1515                 for (sfp = sdp->headfp; sfp; sfp = tsfp) {
1516                         tsfp = sfp->nextfp;
1517                         for (srp = sfp->headrp; srp; srp = tsrp) {
1518                                 tsrp = srp->nextrp;
1519                                 if (sfp->closed || (0 == sg_srp_done(srp, sfp)))
1520                                         sg_finish_rem_req(srp);
1521                         }
1522                         if (sfp->closed) {
1523                                 scsi_device_put(sdp->device);
1524                                 __sg_remove_sfp(sdp, sfp);
1525                         } else {
1526                                 delay = 1;
1527                                 wake_up_interruptible(&sfp->read_wait);
1528                                 kill_fasync(&sfp->async_qp, SIGPOLL,
1529                                             POLL_HUP);
1530                         }
1531                 }
1532                 SCSI_LOG_TIMEOUT(3, printk("sg_remove: dev=%d, dirty\n", sdp->index));
1533                 if (NULL == sdp->headfp) {
1534                         idr_remove(&sg_index_idr, sdp->index);
1535                 }
1536         } else {        /* nothing active, simple case */
1537                 SCSI_LOG_TIMEOUT(3, printk("sg_remove: dev=%d\n", sdp->index));
1538                 idr_remove(&sg_index_idr, sdp->index);
1539         }
1540         write_unlock_irqrestore(&sg_index_lock, iflags);
1541
1542         sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1543         device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1544         cdev_del(sdp->cdev);
1545         sdp->cdev = NULL;
1546         put_disk(sdp->disk);
1547         sdp->disk = NULL;
1548         if (NULL == sdp->headfp)
1549                 kfree(sdp);
1550
1551         if (delay)
1552                 msleep(10);     /* dirty detach so delay device destruction */
1553 }
1554
1555 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1556 module_param_named(def_reserved_size, def_reserved_size, int,
1557                    S_IRUGO | S_IWUSR);
1558 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1559
1560 MODULE_AUTHOR("Douglas Gilbert");
1561 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1562 MODULE_LICENSE("GPL");
1563 MODULE_VERSION(SG_VERSION_STR);
1564 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1565
1566 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1567                 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1568 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1569 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1570
1571 static int __init
1572 init_sg(void)
1573 {
1574         int rc;
1575
1576         if (scatter_elem_sz < PAGE_SIZE) {
1577                 scatter_elem_sz = PAGE_SIZE;
1578                 scatter_elem_sz_prev = scatter_elem_sz;
1579         }
1580         if (def_reserved_size >= 0)
1581                 sg_big_buff = def_reserved_size;
1582         else
1583                 def_reserved_size = sg_big_buff;
1584
1585         rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1586                                     SG_MAX_DEVS, "sg");
1587         if (rc)
1588                 return rc;
1589         sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1590         if ( IS_ERR(sg_sysfs_class) ) {
1591                 rc = PTR_ERR(sg_sysfs_class);
1592                 goto err_out;
1593         }
1594         sg_sysfs_valid = 1;
1595         rc = scsi_register_interface(&sg_interface);
1596         if (0 == rc) {
1597 #ifdef CONFIG_SCSI_PROC_FS
1598                 sg_proc_init();
1599 #endif                          /* CONFIG_SCSI_PROC_FS */
1600                 return 0;
1601         }
1602         class_destroy(sg_sysfs_class);
1603 err_out:
1604         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1605         return rc;
1606 }
1607
1608 static void __exit
1609 exit_sg(void)
1610 {
1611 #ifdef CONFIG_SCSI_PROC_FS
1612         sg_proc_cleanup();
1613 #endif                          /* CONFIG_SCSI_PROC_FS */
1614         scsi_unregister_interface(&sg_interface);
1615         class_destroy(sg_sysfs_class);
1616         sg_sysfs_valid = 0;
1617         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1618                                  SG_MAX_DEVS);
1619         idr_destroy(&sg_index_idr);
1620 }
1621
1622 static int sg_start_req(Sg_request *srp, unsigned char *cmd)
1623 {
1624         int res;
1625         struct request *rq;
1626         Sg_fd *sfp = srp->parentfp;
1627         sg_io_hdr_t *hp = &srp->header;
1628         int dxfer_len = (int) hp->dxfer_len;
1629         int dxfer_dir = hp->dxfer_direction;
1630         unsigned int iov_count = hp->iovec_count;
1631         Sg_scatter_hold *req_schp = &srp->data;
1632         Sg_scatter_hold *rsv_schp = &sfp->reserve;
1633         struct request_queue *q = sfp->parentdp->device->request_queue;
1634         struct rq_map_data *md, map_data;
1635         int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
1636
1637         SCSI_LOG_TIMEOUT(4, printk(KERN_INFO "sg_start_req: dxfer_len=%d\n",
1638                                    dxfer_len));
1639
1640         rq = blk_get_request(q, rw, GFP_ATOMIC);
1641         if (!rq)
1642                 return -ENOMEM;
1643
1644         memcpy(rq->cmd, cmd, hp->cmd_len);
1645
1646         rq->cmd_len = hp->cmd_len;
1647         rq->cmd_type = REQ_TYPE_BLOCK_PC;
1648
1649         srp->rq = rq;
1650         rq->end_io_data = srp;
1651         rq->sense = srp->sense_b;
1652         rq->retries = SG_DEFAULT_RETRIES;
1653
1654         if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1655                 return 0;
1656
1657         if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1658             dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1659             !sfp->parentdp->device->host->unchecked_isa_dma &&
1660             blk_rq_aligned(q, hp->dxferp, dxfer_len))
1661                 md = NULL;
1662         else
1663                 md = &map_data;
1664
1665         if (md) {
1666                 if (!sg_res_in_use(sfp) && dxfer_len <= rsv_schp->bufflen)
1667                         sg_link_reserve(sfp, srp, dxfer_len);
1668                 else {
1669                         res = sg_build_indirect(req_schp, sfp, dxfer_len);
1670                         if (res)
1671                                 return res;
1672                 }
1673
1674                 md->pages = req_schp->pages;
1675                 md->page_order = req_schp->page_order;
1676                 md->nr_entries = req_schp->k_use_sg;
1677         }
1678
1679         if (iov_count)
1680                 res = blk_rq_map_user_iov(q, rq, md, hp->dxferp, iov_count,
1681                                           hp->dxfer_len, GFP_ATOMIC);
1682         else
1683                 res = blk_rq_map_user(q, rq, md, hp->dxferp,
1684                                       hp->dxfer_len, GFP_ATOMIC);
1685
1686         if (!res) {
1687                 srp->bio = rq->bio;
1688
1689                 if (!md) {
1690                         req_schp->dio_in_use = 1;
1691                         hp->info |= SG_INFO_DIRECT_IO;
1692                 }
1693         }
1694         return res;
1695 }
1696
1697 static void
1698 sg_finish_rem_req(Sg_request * srp)
1699 {
1700         Sg_fd *sfp = srp->parentfp;
1701         Sg_scatter_hold *req_schp = &srp->data;
1702
1703         SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n", (int) srp->res_used));
1704         if (srp->res_used)
1705                 sg_unlink_reserve(sfp, srp);
1706         else
1707                 sg_remove_scat(req_schp);
1708
1709         if (srp->rq) {
1710                 if (srp->bio)
1711                         blk_rq_unmap_user(srp->bio);
1712
1713                 blk_put_request(srp->rq);
1714         }
1715
1716         sg_remove_request(sfp, srp);
1717 }
1718
1719 static int
1720 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1721 {
1722         int sg_bufflen = tablesize * sizeof(struct page *);
1723         gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1724
1725         schp->pages = kzalloc(sg_bufflen, gfp_flags);
1726         if (!schp->pages)
1727                 return -ENOMEM;
1728         schp->sglist_len = sg_bufflen;
1729         return tablesize;       /* number of scat_gath elements allocated */
1730 }
1731
1732 static int
1733 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1734 {
1735         int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1736         int sg_tablesize = sfp->parentdp->sg_tablesize;
1737         int blk_size = buff_size, order;
1738         gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
1739
1740         if (blk_size < 0)
1741                 return -EFAULT;
1742         if (0 == blk_size)
1743                 ++blk_size;     /* don't know why */
1744 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1745         blk_size = (blk_size + SG_SECTOR_MSK) & (~SG_SECTOR_MSK);
1746         SCSI_LOG_TIMEOUT(4, printk("sg_build_indirect: buff_size=%d, blk_size=%d\n",
1747                                    buff_size, blk_size));
1748
1749         /* N.B. ret_sz carried into this block ... */
1750         mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1751         if (mx_sc_elems < 0)
1752                 return mx_sc_elems;     /* most likely -ENOMEM */
1753
1754         num = scatter_elem_sz;
1755         if (unlikely(num != scatter_elem_sz_prev)) {
1756                 if (num < PAGE_SIZE) {
1757                         scatter_elem_sz = PAGE_SIZE;
1758                         scatter_elem_sz_prev = PAGE_SIZE;
1759                 } else
1760                         scatter_elem_sz_prev = num;
1761         }
1762
1763         if (sfp->low_dma)
1764                 gfp_mask |= GFP_DMA;
1765
1766         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1767                 gfp_mask |= __GFP_ZERO;
1768
1769         order = get_order(num);
1770 retry:
1771         ret_sz = 1 << (PAGE_SHIFT + order);
1772
1773         for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1774              k++, rem_sz -= ret_sz) {
1775
1776                 num = (rem_sz > scatter_elem_sz_prev) ?
1777                         scatter_elem_sz_prev : rem_sz;
1778
1779                 schp->pages[k] = alloc_pages(gfp_mask, order);
1780                 if (!schp->pages[k])
1781                         goto out;
1782
1783                 if (num == scatter_elem_sz_prev) {
1784                         if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1785                                 scatter_elem_sz = ret_sz;
1786                                 scatter_elem_sz_prev = ret_sz;
1787                         }
1788                 }
1789
1790                 SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k=%d, num=%d, "
1791                                  "ret_sz=%d\n", k, num, ret_sz));
1792         }               /* end of for loop */
1793
1794         schp->page_order = order;
1795         schp->k_use_sg = k;
1796         SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, "
1797                          "rem_sz=%d\n", k, rem_sz));
1798
1799         schp->bufflen = blk_size;
1800         if (rem_sz > 0) /* must have failed */
1801                 return -ENOMEM;
1802         return 0;
1803 out:
1804         for (i = 0; i < k; i++)
1805                 __free_pages(schp->pages[k], order);
1806
1807         if (--order >= 0)
1808                 goto retry;
1809
1810         return -ENOMEM;
1811 }
1812
1813 static void
1814 sg_remove_scat(Sg_scatter_hold * schp)
1815 {
1816         SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1817         if (schp->pages && schp->sglist_len > 0) {
1818                 if (!schp->dio_in_use) {
1819                         int k;
1820
1821                         for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1822                                 SCSI_LOG_TIMEOUT(5, printk(
1823                                     "sg_remove_scat: k=%d, pg=0x%p\n",
1824                                     k, schp->pages[k]));
1825                                 __free_pages(schp->pages[k], schp->page_order);
1826                         }
1827
1828                         kfree(schp->pages);
1829                 }
1830         }
1831         memset(schp, 0, sizeof (*schp));
1832 }
1833
1834 static int
1835 sg_read_xfer(Sg_request * srp)
1836 {
1837         sg_io_hdr_t *hp = &srp->header;
1838         Sg_scatter_hold *schp = &srp->data;
1839         int num_xfer = 0;
1840         int dxfer_dir = hp->dxfer_direction;
1841         int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
1842
1843         if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_FROM_DEV == dxfer_dir)
1844             || (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
1845                 num_xfer = hp->dxfer_len;
1846                 if (schp->bufflen < num_xfer)
1847                         num_xfer = schp->bufflen;
1848         }
1849         if ((num_xfer <= 0) || (schp->dio_in_use) ||
1850             (new_interface
1851              && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
1852                 return 0;
1853
1854         SCSI_LOG_TIMEOUT(4, printk("sg_read_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
1855                           num_xfer, (int)hp->iovec_count, schp->k_use_sg));
1856         return 0;
1857 }
1858
1859 static int
1860 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1861 {
1862         Sg_scatter_hold *schp = &srp->data;
1863         int k, num;
1864
1865         SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n",
1866                                    num_read_xfer));
1867         if ((!outp) || (num_read_xfer <= 0))
1868                 return 0;
1869
1870         blk_rq_unmap_user(srp->bio);
1871         srp->bio = NULL;
1872
1873         num = 1 << (PAGE_SHIFT + schp->page_order);
1874         for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1875                 if (num > num_read_xfer) {
1876                         if (__copy_to_user(outp, page_address(schp->pages[k]),
1877                                            num_read_xfer))
1878                                 return -EFAULT;
1879                         break;
1880                 } else {
1881                         if (__copy_to_user(outp, page_address(schp->pages[k]),
1882                                            num))
1883                                 return -EFAULT;
1884                         num_read_xfer -= num;
1885                         if (num_read_xfer <= 0)
1886                                 break;
1887                         outp += num;
1888                 }
1889         }
1890
1891         return 0;
1892 }
1893
1894 static void
1895 sg_build_reserve(Sg_fd * sfp, int req_size)
1896 {
1897         Sg_scatter_hold *schp = &sfp->reserve;
1898
1899         SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
1900         do {
1901                 if (req_size < PAGE_SIZE)
1902                         req_size = PAGE_SIZE;
1903                 if (0 == sg_build_indirect(schp, sfp, req_size))
1904                         return;
1905                 else
1906                         sg_remove_scat(schp);
1907                 req_size >>= 1; /* divide by 2 */
1908         } while (req_size > (PAGE_SIZE / 2));
1909 }
1910
1911 static void
1912 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
1913 {
1914         Sg_scatter_hold *req_schp = &srp->data;
1915         Sg_scatter_hold *rsv_schp = &sfp->reserve;
1916         int k, num, rem;
1917
1918         srp->res_used = 1;
1919         SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
1920         rem = size;
1921
1922         num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1923         for (k = 0; k < rsv_schp->k_use_sg; k++) {
1924                 if (rem <= num) {
1925                         req_schp->k_use_sg = k + 1;
1926                         req_schp->sglist_len = rsv_schp->sglist_len;
1927                         req_schp->pages = rsv_schp->pages;
1928
1929                         req_schp->bufflen = size;
1930                         req_schp->page_order = rsv_schp->page_order;
1931                         break;
1932                 } else
1933                         rem -= num;
1934         }
1935
1936         if (k >= rsv_schp->k_use_sg)
1937                 SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
1938 }
1939
1940 static void
1941 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
1942 {
1943         Sg_scatter_hold *req_schp = &srp->data;
1944
1945         SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->k_use_sg=%d\n",
1946                                    (int) req_schp->k_use_sg));
1947         req_schp->k_use_sg = 0;
1948         req_schp->bufflen = 0;
1949         req_schp->pages = NULL;
1950         req_schp->page_order = 0;
1951         req_schp->sglist_len = 0;
1952         sfp->save_scat_len = 0;
1953         srp->res_used = 0;
1954 }
1955
1956 static Sg_request *
1957 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
1958 {
1959         Sg_request *resp;
1960         unsigned long iflags;
1961
1962         write_lock_irqsave(&sfp->rq_list_lock, iflags);
1963         for (resp = sfp->headrp; resp; resp = resp->nextrp) {
1964                 /* look for requests that are ready + not SG_IO owned */
1965                 if ((1 == resp->done) && (!resp->sg_io_owned) &&
1966                     ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
1967                         resp->done = 2; /* guard against other readers */
1968                         break;
1969                 }
1970         }
1971         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1972         return resp;
1973 }
1974
1975 #ifdef CONFIG_SCSI_PROC_FS
1976 static Sg_request *
1977 sg_get_nth_request(Sg_fd * sfp, int nth)
1978 {
1979         Sg_request *resp;
1980         unsigned long iflags;
1981         int k;
1982
1983         read_lock_irqsave(&sfp->rq_list_lock, iflags);
1984         for (k = 0, resp = sfp->headrp; resp && (k < nth);
1985              ++k, resp = resp->nextrp) ;
1986         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1987         return resp;
1988 }
1989 #endif
1990
1991 /* always adds to end of list */
1992 static Sg_request *
1993 sg_add_request(Sg_fd * sfp)
1994 {
1995         int k;
1996         unsigned long iflags;
1997         Sg_request *resp;
1998         Sg_request *rp = sfp->req_arr;
1999
2000         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2001         resp = sfp->headrp;
2002         if (!resp) {
2003                 memset(rp, 0, sizeof (Sg_request));
2004                 rp->parentfp = sfp;
2005                 resp = rp;
2006                 sfp->headrp = resp;
2007         } else {
2008                 if (0 == sfp->cmd_q)
2009                         resp = NULL;    /* command queuing disallowed */
2010                 else {
2011                         for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2012                                 if (!rp->parentfp)
2013                                         break;
2014                         }
2015                         if (k < SG_MAX_QUEUE) {
2016                                 memset(rp, 0, sizeof (Sg_request));
2017                                 rp->parentfp = sfp;
2018                                 while (resp->nextrp)
2019                                         resp = resp->nextrp;
2020                                 resp->nextrp = rp;
2021                                 resp = rp;
2022                         } else
2023                                 resp = NULL;
2024                 }
2025         }
2026         if (resp) {
2027                 resp->nextrp = NULL;
2028                 resp->header.duration = jiffies_to_msecs(jiffies);
2029         }
2030         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2031         return resp;
2032 }
2033
2034 /* Return of 1 for found; 0 for not found */
2035 static int
2036 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2037 {
2038         Sg_request *prev_rp;
2039         Sg_request *rp;
2040         unsigned long iflags;
2041         int res = 0;
2042
2043         if ((!sfp) || (!srp) || (!sfp->headrp))
2044                 return res;
2045         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2046         prev_rp = sfp->headrp;
2047         if (srp == prev_rp) {
2048                 sfp->headrp = prev_rp->nextrp;
2049                 prev_rp->parentfp = NULL;
2050                 res = 1;
2051         } else {
2052                 while ((rp = prev_rp->nextrp)) {
2053                         if (srp == rp) {
2054                                 prev_rp->nextrp = rp->nextrp;
2055                                 rp->parentfp = NULL;
2056                                 res = 1;
2057                                 break;
2058                         }
2059                         prev_rp = rp;
2060                 }
2061         }
2062         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2063         return res;
2064 }
2065
2066 #ifdef CONFIG_SCSI_PROC_FS
2067 static Sg_fd *
2068 sg_get_nth_sfp(Sg_device * sdp, int nth)
2069 {
2070         Sg_fd *resp;
2071         unsigned long iflags;
2072         int k;
2073
2074         read_lock_irqsave(&sg_index_lock, iflags);
2075         for (k = 0, resp = sdp->headfp; resp && (k < nth);
2076              ++k, resp = resp->nextfp) ;
2077         read_unlock_irqrestore(&sg_index_lock, iflags);
2078         return resp;
2079 }
2080 #endif
2081
2082 static Sg_fd *
2083 sg_add_sfp(Sg_device * sdp, int dev)
2084 {
2085         Sg_fd *sfp;
2086         unsigned long iflags;
2087         int bufflen;
2088
2089         sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2090         if (!sfp)
2091                 return NULL;
2092
2093         init_waitqueue_head(&sfp->read_wait);
2094         rwlock_init(&sfp->rq_list_lock);
2095
2096         sfp->timeout = SG_DEFAULT_TIMEOUT;
2097         sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2098         sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2099         sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
2100             sdp->device->host->unchecked_isa_dma : 1;
2101         sfp->cmd_q = SG_DEF_COMMAND_Q;
2102         sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2103         sfp->parentdp = sdp;
2104         write_lock_irqsave(&sg_index_lock, iflags);
2105         if (!sdp->headfp)
2106                 sdp->headfp = sfp;
2107         else {                  /* add to tail of existing list */
2108                 Sg_fd *pfp = sdp->headfp;
2109                 while (pfp->nextfp)
2110                         pfp = pfp->nextfp;
2111                 pfp->nextfp = sfp;
2112         }
2113         write_unlock_irqrestore(&sg_index_lock, iflags);
2114         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));
2115         if (unlikely(sg_big_buff != def_reserved_size))
2116                 sg_big_buff = def_reserved_size;
2117
2118         bufflen = min_t(int, sg_big_buff,
2119                         sdp->device->request_queue->max_sectors * 512);
2120         sg_build_reserve(sfp, bufflen);
2121         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp:   bufflen=%d, k_use_sg=%d\n",
2122                            sfp->reserve.bufflen, sfp->reserve.k_use_sg));
2123         return sfp;
2124 }
2125
2126 static void
2127 __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2128 {
2129         Sg_fd *fp;
2130         Sg_fd *prev_fp;
2131
2132         prev_fp = sdp->headfp;
2133         if (sfp == prev_fp)
2134                 sdp->headfp = prev_fp->nextfp;
2135         else {
2136                 while ((fp = prev_fp->nextfp)) {
2137                         if (sfp == fp) {
2138                                 prev_fp->nextfp = fp->nextfp;
2139                                 break;
2140                         }
2141                         prev_fp = fp;
2142                 }
2143         }
2144         if (sfp->reserve.bufflen > 0) {
2145                 SCSI_LOG_TIMEOUT(6,
2146                         printk("__sg_remove_sfp:    bufflen=%d, k_use_sg=%d\n",
2147                         (int) sfp->reserve.bufflen, (int) sfp->reserve.k_use_sg));
2148                 sg_remove_scat(&sfp->reserve);
2149         }
2150         sfp->parentdp = NULL;
2151         SCSI_LOG_TIMEOUT(6, printk("__sg_remove_sfp:    sfp=0x%p\n", sfp));
2152         kfree(sfp);
2153 }
2154
2155 /* Returns 0 in normal case, 1 when detached and sdp object removed */
2156 static int
2157 sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2158 {
2159         Sg_request *srp;
2160         Sg_request *tsrp;
2161         int dirty = 0;
2162         int res = 0;
2163
2164         for (srp = sfp->headrp; srp; srp = tsrp) {
2165                 tsrp = srp->nextrp;
2166                 if (sg_srp_done(srp, sfp))
2167                         sg_finish_rem_req(srp);
2168                 else
2169                         ++dirty;
2170         }
2171         if (0 == dirty) {
2172                 unsigned long iflags;
2173
2174                 write_lock_irqsave(&sg_index_lock, iflags);
2175                 __sg_remove_sfp(sdp, sfp);
2176                 if (sdp->detached && (NULL == sdp->headfp)) {
2177                         idr_remove(&sg_index_idr, sdp->index);
2178                         kfree(sdp);
2179                         res = 1;
2180                 }
2181                 write_unlock_irqrestore(&sg_index_lock, iflags);
2182         } else {
2183                 /* MOD_INC's to inhibit unloading sg and associated adapter driver */
2184                 /* only bump the access_count if we actually succeeded in
2185                  * throwing another counter on the host module */
2186                 scsi_device_get(sdp->device);   /* XXX: retval ignored? */
2187                 sfp->closed = 1;        /* flag dirty state on this fd */
2188                 SCSI_LOG_TIMEOUT(1, printk("sg_remove_sfp: worrisome, %d writes pending\n",
2189                                   dirty));
2190         }
2191         return res;
2192 }
2193
2194 static int
2195 sg_res_in_use(Sg_fd * sfp)
2196 {
2197         const Sg_request *srp;
2198         unsigned long iflags;
2199
2200         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2201         for (srp = sfp->headrp; srp; srp = srp->nextrp)
2202                 if (srp->res_used)
2203                         break;
2204         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2205         return srp ? 1 : 0;
2206 }
2207
2208 #ifdef CONFIG_SCSI_PROC_FS
2209 static int
2210 sg_idr_max_id(int id, void *p, void *data)
2211 {
2212         int *k = data;
2213
2214         if (*k < id)
2215                 *k = id;
2216
2217         return 0;
2218 }
2219
2220 static int
2221 sg_last_dev(void)
2222 {
2223         int k = -1;
2224         unsigned long iflags;
2225
2226         read_lock_irqsave(&sg_index_lock, iflags);
2227         idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2228         read_unlock_irqrestore(&sg_index_lock, iflags);
2229         return k + 1;           /* origin 1 */
2230 }
2231 #endif
2232
2233 static Sg_device *
2234 sg_get_dev(int dev)
2235 {
2236         Sg_device *sdp;
2237         unsigned long iflags;
2238
2239         read_lock_irqsave(&sg_index_lock, iflags);
2240         sdp = idr_find(&sg_index_idr, dev);
2241         read_unlock_irqrestore(&sg_index_lock, iflags);
2242
2243         return sdp;
2244 }
2245
2246 #ifdef CONFIG_SCSI_PROC_FS
2247
2248 static struct proc_dir_entry *sg_proc_sgp = NULL;
2249
2250 static char sg_proc_sg_dirname[] = "scsi/sg";
2251
2252 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2253
2254 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2255 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2256                                   size_t count, loff_t *off);
2257 static struct file_operations adio_fops = {
2258         /* .owner, .read and .llseek added in sg_proc_init() */
2259         .open = sg_proc_single_open_adio,
2260         .write = sg_proc_write_adio,
2261         .release = single_release,
2262 };
2263
2264 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2265 static ssize_t sg_proc_write_dressz(struct file *filp,
2266                 const char __user *buffer, size_t count, loff_t *off);
2267 static struct file_operations dressz_fops = {
2268         .open = sg_proc_single_open_dressz,
2269         .write = sg_proc_write_dressz,
2270         .release = single_release,
2271 };
2272
2273 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2274 static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2275 static struct file_operations version_fops = {
2276         .open = sg_proc_single_open_version,
2277         .release = single_release,
2278 };
2279
2280 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2281 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2282 static struct file_operations devhdr_fops = {
2283         .open = sg_proc_single_open_devhdr,
2284         .release = single_release,
2285 };
2286
2287 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2288 static int sg_proc_open_dev(struct inode *inode, struct file *file);
2289 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2290 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2291 static void dev_seq_stop(struct seq_file *s, void *v);
2292 static struct file_operations dev_fops = {
2293         .open = sg_proc_open_dev,
2294         .release = seq_release,
2295 };
2296 static struct seq_operations dev_seq_ops = {
2297         .start = dev_seq_start,
2298         .next  = dev_seq_next,
2299         .stop  = dev_seq_stop,
2300         .show  = sg_proc_seq_show_dev,
2301 };
2302
2303 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2304 static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2305 static struct file_operations devstrs_fops = {
2306         .open = sg_proc_open_devstrs,
2307         .release = seq_release,
2308 };
2309 static struct seq_operations devstrs_seq_ops = {
2310         .start = dev_seq_start,
2311         .next  = dev_seq_next,
2312         .stop  = dev_seq_stop,
2313         .show  = sg_proc_seq_show_devstrs,
2314 };
2315
2316 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2317 static int sg_proc_open_debug(struct inode *inode, struct file *file);
2318 static struct file_operations debug_fops = {
2319         .open = sg_proc_open_debug,
2320         .release = seq_release,
2321 };
2322 static struct seq_operations debug_seq_ops = {
2323         .start = dev_seq_start,
2324         .next  = dev_seq_next,
2325         .stop  = dev_seq_stop,
2326         .show  = sg_proc_seq_show_debug,
2327 };
2328
2329
2330 struct sg_proc_leaf {
2331         const char * name;
2332         struct file_operations * fops;
2333 };
2334
2335 static struct sg_proc_leaf sg_proc_leaf_arr[] = {
2336         {"allow_dio", &adio_fops},
2337         {"debug", &debug_fops},
2338         {"def_reserved_size", &dressz_fops},
2339         {"device_hdr", &devhdr_fops},
2340         {"devices", &dev_fops},
2341         {"device_strs", &devstrs_fops},
2342         {"version", &version_fops}
2343 };
2344
2345 static int
2346 sg_proc_init(void)
2347 {
2348         int k, mask;
2349         int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2350         struct sg_proc_leaf * leaf;
2351
2352         sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2353         if (!sg_proc_sgp)
2354                 return 1;
2355         for (k = 0; k < num_leaves; ++k) {
2356                 leaf = &sg_proc_leaf_arr[k];
2357                 mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2358                 leaf->fops->owner = THIS_MODULE;
2359                 leaf->fops->read = seq_read;
2360                 leaf->fops->llseek = seq_lseek;
2361                 proc_create(leaf->name, mask, sg_proc_sgp, leaf->fops);
2362         }
2363         return 0;
2364 }
2365
2366 static void
2367 sg_proc_cleanup(void)
2368 {
2369         int k;
2370         int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2371
2372         if (!sg_proc_sgp)
2373                 return;
2374         for (k = 0; k < num_leaves; ++k)
2375                 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2376         remove_proc_entry(sg_proc_sg_dirname, NULL);
2377 }
2378
2379
2380 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2381 {
2382         seq_printf(s, "%d\n", *((int *)s->private));
2383         return 0;
2384 }
2385
2386 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2387 {
2388         return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2389 }
2390
2391 static ssize_t
2392 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2393                    size_t count, loff_t *off)
2394 {
2395         int num;
2396         char buff[11];
2397
2398         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2399                 return -EACCES;
2400         num = (count < 10) ? count : 10;
2401         if (copy_from_user(buff, buffer, num))
2402                 return -EFAULT;
2403         buff[num] = '\0';
2404         sg_allow_dio = simple_strtoul(buff, NULL, 10) ? 1 : 0;
2405         return count;
2406 }
2407
2408 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2409 {
2410         return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2411 }
2412
2413 static ssize_t
2414 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2415                      size_t count, loff_t *off)
2416 {
2417         int num;
2418         unsigned long k = ULONG_MAX;
2419         char buff[11];
2420
2421         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2422                 return -EACCES;
2423         num = (count < 10) ? count : 10;
2424         if (copy_from_user(buff, buffer, num))
2425                 return -EFAULT;
2426         buff[num] = '\0';
2427         k = simple_strtoul(buff, NULL, 10);
2428         if (k <= 1048576) {     /* limit "big buff" to 1 MB */
2429                 sg_big_buff = k;
2430                 return count;
2431         }
2432         return -ERANGE;
2433 }
2434
2435 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2436 {
2437         seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2438                    sg_version_date);
2439         return 0;
2440 }
2441
2442 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2443 {
2444         return single_open(file, sg_proc_seq_show_version, NULL);
2445 }
2446
2447 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2448 {
2449         seq_printf(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\t"
2450                    "online\n");
2451         return 0;
2452 }
2453
2454 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2455 {
2456         return single_open(file, sg_proc_seq_show_devhdr, NULL);
2457 }
2458
2459 struct sg_proc_deviter {
2460         loff_t  index;
2461         size_t  max;
2462 };
2463
2464 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2465 {
2466         struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2467
2468         s->private = it;
2469         if (! it)
2470                 return NULL;
2471
2472         it->index = *pos;
2473         it->max = sg_last_dev();
2474         if (it->index >= it->max)
2475                 return NULL;
2476         return it;
2477 }
2478
2479 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2480 {
2481         struct sg_proc_deviter * it = s->private;
2482
2483         *pos = ++it->index;
2484         return (it->index < it->max) ? it : NULL;
2485 }
2486
2487 static void dev_seq_stop(struct seq_file *s, void *v)
2488 {
2489         kfree(s->private);
2490 }
2491
2492 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2493 {
2494         return seq_open(file, &dev_seq_ops);
2495 }
2496
2497 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2498 {
2499         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2500         Sg_device *sdp;
2501         struct scsi_device *scsidp;
2502
2503         sdp = it ? sg_get_dev(it->index) : NULL;
2504         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2505                 seq_printf(s, "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n",
2506                               scsidp->host->host_no, scsidp->channel,
2507                               scsidp->id, scsidp->lun, (int) scsidp->type,
2508                               1,
2509                               (int) scsidp->queue_depth,
2510                               (int) scsidp->device_busy,
2511                               (int) scsi_device_online(scsidp));
2512         else
2513                 seq_printf(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2514         return 0;
2515 }
2516
2517 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2518 {
2519         return seq_open(file, &devstrs_seq_ops);
2520 }
2521
2522 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2523 {
2524         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2525         Sg_device *sdp;
2526         struct scsi_device *scsidp;
2527
2528         sdp = it ? sg_get_dev(it->index) : NULL;
2529         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2530                 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2531                            scsidp->vendor, scsidp->model, scsidp->rev);
2532         else
2533                 seq_printf(s, "<no active device>\n");
2534         return 0;
2535 }
2536
2537 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2538 {
2539         int k, m, new_interface, blen, usg;
2540         Sg_request *srp;
2541         Sg_fd *fp;
2542         const sg_io_hdr_t *hp;
2543         const char * cp;
2544         unsigned int ms;
2545
2546         for (k = 0; (fp = sg_get_nth_sfp(sdp, k)); ++k) {
2547                 seq_printf(s, "   FD(%d): timeout=%dms bufflen=%d "
2548                            "(res)sgat=%d low_dma=%d\n", k + 1,
2549                            jiffies_to_msecs(fp->timeout),
2550                            fp->reserve.bufflen,
2551                            (int) fp->reserve.k_use_sg,
2552                            (int) fp->low_dma);
2553                 seq_printf(s, "   cmd_q=%d f_packid=%d k_orphan=%d closed=%d\n",
2554                            (int) fp->cmd_q, (int) fp->force_packid,
2555                            (int) fp->keep_orphan, (int) fp->closed);
2556                 for (m = 0; (srp = sg_get_nth_request(fp, m)); ++m) {
2557                         hp = &srp->header;
2558                         new_interface = (hp->interface_id == '\0') ? 0 : 1;
2559                         if (srp->res_used) {
2560                                 if (new_interface &&
2561                                     (SG_FLAG_MMAP_IO & hp->flags))
2562                                         cp = "     mmap>> ";
2563                                 else
2564                                         cp = "     rb>> ";
2565                         } else {
2566                                 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2567                                         cp = "     dio>> ";
2568                                 else
2569                                         cp = "     ";
2570                         }
2571                         seq_printf(s, cp);
2572                         blen = srp->data.bufflen;
2573                         usg = srp->data.k_use_sg;
2574                         seq_printf(s, srp->done ?
2575                                    ((1 == srp->done) ?  "rcv:" : "fin:")
2576                                    : "act:");
2577                         seq_printf(s, " id=%d blen=%d",
2578                                    srp->header.pack_id, blen);
2579                         if (srp->done)
2580                                 seq_printf(s, " dur=%d", hp->duration);
2581                         else {
2582                                 ms = jiffies_to_msecs(jiffies);
2583                                 seq_printf(s, " t_o/elap=%d/%d",
2584                                         (new_interface ? hp->timeout :
2585                                                   jiffies_to_msecs(fp->timeout)),
2586                                         (ms > hp->duration ? ms - hp->duration : 0));
2587                         }
2588                         seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2589                                    (int) srp->data.cmd_opcode);
2590                 }
2591                 if (0 == m)
2592                         seq_printf(s, "     No requests active\n");
2593         }
2594 }
2595
2596 static int sg_proc_open_debug(struct inode *inode, struct file *file)
2597 {
2598         return seq_open(file, &debug_seq_ops);
2599 }
2600
2601 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2602 {
2603         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2604         Sg_device *sdp;
2605
2606         if (it && (0 == it->index)) {
2607                 seq_printf(s, "max_active_device=%d(origin 1)\n",
2608                            (int)it->max);
2609                 seq_printf(s, " def_reserved_size=%d\n", sg_big_buff);
2610         }
2611         sdp = it ? sg_get_dev(it->index) : NULL;
2612         if (sdp) {
2613                 struct scsi_device *scsidp = sdp->device;
2614
2615                 if (NULL == scsidp) {
2616                         seq_printf(s, "device %d detached ??\n",
2617                                    (int)it->index);
2618                         return 0;
2619                 }
2620
2621                 if (sg_get_nth_sfp(sdp, 0)) {
2622                         seq_printf(s, " >>> device=%s ",
2623                                 sdp->disk->disk_name);
2624                         if (sdp->detached)
2625                                 seq_printf(s, "detached pending close ");
2626                         else
2627                                 seq_printf
2628                                     (s, "scsi%d chan=%d id=%d lun=%d   em=%d",
2629                                      scsidp->host->host_no,
2630                                      scsidp->channel, scsidp->id,
2631                                      scsidp->lun,
2632                                      scsidp->host->hostt->emulated);
2633                         seq_printf(s, " sg_tablesize=%d excl=%d\n",
2634                                    sdp->sg_tablesize, sdp->exclude);
2635                 }
2636                 sg_proc_debug_helper(s, sdp);
2637         }
2638         return 0;
2639 }
2640
2641 #endif                          /* CONFIG_SCSI_PROC_FS */
2642
2643 module_init(init_sg);
2644 module_exit(exit_sg);