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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/seq_file.h>
  47 #include <linux/blkdev.h>
  48 #include <linux/delay.h>
  49 #include <linux/scatterlist.h>
  50
  51 #include "scsi.h"
  52 #include <scsi/scsi_dbg.h>
  53 #include <scsi/scsi_host.h>
  54 #include <scsi/scsi_driver.h>
  55 #include <scsi/scsi_ioctl.h>
  56 #include <scsi/sg.h>
  57
  58 #include "scsi_logging.h"
  59
  60 #ifdef CONFIG_SCSI_PROC_FS
  61 #include <linux/proc_fs.h>
  62 static char *sg_version_date = "20061027";
  63
  64 static int sg_proc_init(void);
  65 static void sg_proc_cleanup(void);
  66 #endif
  67
  68 #define SG_ALLOW_DIO_DEF 0
  69 #define SG_ALLOW_DIO_CODE /* compile out by commenting this define */
  70
  71 #define SG_MAX_DEVS 32768
  72
  73 /*
  74  * Suppose you want to calculate the formula muldiv(x,m,d)=int(x * m / d)
  75  * Then when using 32 bit integers x * m may overflow during the calculation.
  76  * Replacing muldiv(x) by muldiv(x)=((x % d) * m) / d + int(x / d) * m
  77  * calculates the same, but prevents the overflow when both m and d
  78  * are "small" numbers (like HZ and USER_HZ).
  79  * Of course an overflow is inavoidable if the result of muldiv doesn't fit
  80  * in 32 bits.
  81  */
  82 #define MULDIV(X,MUL,DIV) ((((X % DIV) * MUL) / DIV) + ((X / DIV) * MUL))
  83
  84 #define SG_DEFAULT_TIMEOUT MULDIV(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
  85
  86 int sg_big_buff = SG_DEF_RESERVED_SIZE;
  87 /* N.B. This variable is readable and writeable via
  88    /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
  89    of this size (or less if there is not enough memory) will be reserved
  90    for use by this file descriptor. [Deprecated usage: this variable is also
  91    readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
  92    the kernel (i.e. it is not a module).] */
  93 static int def_reserved_size = -1;      /* picks up init parameter */
  94 static int sg_allow_dio = SG_ALLOW_DIO_DEF;
  95
  96 static int scatter_elem_sz = SG_SCATTER_SZ;
  97 static int scatter_elem_sz_prev = SG_SCATTER_SZ;
  98
  99 #define SG_SECTOR_SZ 512
 100 #define SG_SECTOR_MSK (SG_SECTOR_SZ - 1)
 101
 102 #define SG_DEV_ARR_LUMP 32      /* amount to over allocate sg_dev_arr by */
 103
 104 static int sg_add(struct class_device *, struct class_interface *);
 105 static void sg_remove(struct class_device *, struct class_interface *);
 106
 107 static DEFINE_RWLOCK(sg_dev_arr_lock);  /* Also used to lock
 108                                                            file descriptor list for device */
 109
 110 static struct class_interface sg_interface = {
 111         .add            = sg_add,
 112         .remove         = 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 short sglist_len; /* size of malloc'd scatter-gather list ++ */
 118         unsigned bufflen;       /* Size of (aggregate) data buffer */
 119         unsigned b_malloc_len;  /* actual len malloc'ed in buffer */
 120         struct scatterlist *buffer;/* scatter list */
 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 } Sg_request;
 139
 140 typedef struct sg_fd {          /* holds the state of a file descriptor */
 141         struct sg_fd *nextfp;   /* NULL when last opened fd on this device */
 142         struct sg_device *parentdp;     /* owning device */
 143         wait_queue_head_t read_wait;    /* queue read until command done */
 144         rwlock_t rq_list_lock;  /* protect access to list in req_arr */
 145         int timeout;            /* defaults to SG_DEFAULT_TIMEOUT      */
 146         int timeout_user;       /* defaults to SG_DEFAULT_TIMEOUT_USER */
 147         Sg_scatter_hold reserve;        /* buffer held for this file descriptor */
 148         unsigned save_scat_len; /* original length of trunc. scat. element */
 149         Sg_request *headrp;     /* head of request slist, NULL->empty */
 150         struct fasync_struct *async_qp; /* used by asynchronous notification */
 151         Sg_request req_arr[SG_MAX_QUEUE];       /* used as singly-linked list */
 152         char low_dma;           /* as in parent but possibly overridden to 1 */
 153         char force_packid;      /* 1 -> pack_id input to read(), 0 -> ignored */
 154         volatile char closed;   /* 1 -> fd closed but request(s) outstanding */
 155         char cmd_q;             /* 1 -> allow command queuing, 0 -> don't */
 156         char next_cmd_len;      /* 0 -> automatic (def), >0 -> use on next write() */
 157         char keep_orphan;       /* 0 -> drop orphan (def), 1 -> keep for read() */
 158         char mmap_called;       /* 0 -> mmap() never called on this fd */
 159 } Sg_fd;
 160
 161 typedef struct sg_device { /* holds the state of each scsi generic device */
 162         struct scsi_device *device;
 163         wait_queue_head_t o_excl_wait;  /* queue open() when O_EXCL in use */
 164         int sg_tablesize;       /* adapter's max scatter-gather table size */
 165         Sg_fd *headfp;          /* first open fd belonging to this device */
 166         volatile char detached; /* 0->attached, 1->detached pending removal */
 167         volatile char exclude;  /* opened for exclusive access */
 168         char sgdebug;           /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
 169         struct gendisk *disk;
 170         struct cdev * cdev;     /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
 171 } Sg_device;
 172
 173 static int sg_fasync(int fd, struct file *filp, int mode);
 174 /* tasklet or soft irq callback */
 175 static void sg_cmd_done(void *data, char *sense, int result, int resid);
 176 static int sg_start_req(Sg_request * srp);
 177 static void sg_finish_rem_req(Sg_request * srp);
 178 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
 179 static int sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp,
 180                          int tablesize);
 181 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
 182                            Sg_request * srp);
 183 static ssize_t sg_new_write(Sg_fd * sfp, const char __user *buf, size_t count,
 184                             int blocking, int read_only, Sg_request ** o_srp);
 185 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
 186                            unsigned char *cmnd, int timeout, int blocking);
 187 static int sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
 188                       int wr_xf, int *countp, unsigned char __user **up);
 189 static int sg_write_xfer(Sg_request * srp);
 190 static int sg_read_xfer(Sg_request * srp);
 191 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
 192 static void sg_remove_scat(Sg_scatter_hold * schp);
 193 static void sg_build_reserve(Sg_fd * sfp, int req_size);
 194 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
 195 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
 196 static struct page *sg_page_malloc(int rqSz, int lowDma, int *retSzp);
 197 static void sg_page_free(struct page *page, int size);
 198 static Sg_fd *sg_add_sfp(Sg_device * sdp, int dev);
 199 static int sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
 200 static void __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
 201 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
 202 static Sg_request *sg_add_request(Sg_fd * sfp);
 203 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
 204 static int sg_res_in_use(Sg_fd * sfp);
 205 static int sg_allow_access(unsigned char opcode, char dev_type);
 206 static int sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len);
 207 static Sg_device *sg_get_dev(int dev);
 208 #ifdef CONFIG_SCSI_PROC_FS
 209 static int sg_last_dev(void);
 210 #endif
 211
 212 static Sg_device **sg_dev_arr = NULL;
 213 static int sg_dev_max;
 214 static int sg_nr_dev;
 215
 216 #define SZ_SG_HEADER sizeof(struct sg_header)
 217 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
 218 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
 219 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
 220
 221 static int
 222 sg_open(struct inode *inode, struct file *filp)
 223 {
 224         int dev = iminor(inode);
 225         int flags = filp->f_flags;
 226         struct request_queue *q;
 227         Sg_device *sdp;
 228         Sg_fd *sfp;
 229         int res;
 230         int retval;
 231
 232         nonseekable_open(inode, filp);
 233         SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags));
 234         sdp = sg_get_dev(dev);
 235         if ((!sdp) || (!sdp->device))
 236                 return -ENXIO;
 237         if (sdp->detached)
 238                 return -ENODEV;
 239
 240         /* This driver's module count bumped by fops_get in <linux/fs.h> */
 241         /* Prevent the device driver from vanishing while we sleep */
 242         retval = scsi_device_get(sdp->device);
 243         if (retval)
 244                 return retval;
 245
 246         if (!((flags & O_NONBLOCK) ||
 247               scsi_block_when_processing_errors(sdp->device))) {
 248                 retval = -ENXIO;
 249                 /* we are in error recovery for this device */
 250                 goto error_out;
 251         }
 252
 253         if (flags & O_EXCL) {
 254                 if (O_RDONLY == (flags & O_ACCMODE)) {
 255                         retval = -EPERM; /* Can't lock it with read only access */
 256                         goto error_out;
 257                 }
 258                 if (sdp->headfp && (flags & O_NONBLOCK)) {
 259                         retval = -EBUSY;
 260                         goto error_out;
 261                 }
 262                 res = 0;
 263                 __wait_event_interruptible(sdp->o_excl_wait,
 264                         ((sdp->headfp || sdp->exclude) ? 0 : (sdp->exclude = 1)), res);
 265                 if (res) {
 266                         retval = res;   /* -ERESTARTSYS because signal hit process */
 267                         goto error_out;
 268                 }
 269         } else if (sdp->exclude) {      /* some other fd has an exclusive lock on dev */
 270                 if (flags & O_NONBLOCK) {
 271                         retval = -EBUSY;
 272                         goto error_out;
 273                 }
 274                 res = 0;
 275                 __wait_event_interruptible(sdp->o_excl_wait, (!sdp->exclude),
 276                                            res);
 277                 if (res) {
 278                         retval = res;   /* -ERESTARTSYS because signal hit process */
 279                         goto error_out;
 280                 }
 281         }
 282         if (sdp->detached) {
 283                 retval = -ENODEV;
 284                 goto error_out;
 285         }
 286         if (!sdp->headfp) {     /* no existing opens on this device */
 287                 sdp->sgdebug = 0;
 288                 q = sdp->device->request_queue;
 289                 sdp->sg_tablesize = min(q->max_hw_segments,
 290                                         q->max_phys_segments);
 291         }
 292         if ((sfp = sg_add_sfp(sdp, dev)))
 293                 filp->private_data = sfp;
 294         else {
 295                 if (flags & O_EXCL)
 296                         sdp->exclude = 0;       /* undo if error */
 297                 retval = -ENOMEM;
 298                 goto error_out;
 299         }
 300         return 0;
 301
 302       error_out:
 303         scsi_device_put(sdp->device);
 304         return retval;
 305 }
 306
 307 /* Following function was formerly called 'sg_close' */
 308 static int
 309 sg_release(struct inode *inode, struct file *filp)
 310 {
 311         Sg_device *sdp;
 312         Sg_fd *sfp;
 313
 314         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 315                 return -ENXIO;
 316         SCSI_LOG_TIMEOUT(3, printk("sg_release: %s\n", sdp->disk->disk_name));
 317         sg_fasync(-1, filp, 0); /* remove filp from async notification list */
 318         if (0 == sg_remove_sfp(sdp, sfp)) {     /* Returns 1 when sdp gone */
 319                 if (!sdp->detached) {
 320                         scsi_device_put(sdp->device);
 321                 }
 322                 sdp->exclude = 0;
 323                 wake_up_interruptible(&sdp->o_excl_wait);
 324         }
 325         return 0;
 326 }
 327
 328 static ssize_t
 329 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
 330 {
 331         Sg_device *sdp;
 332         Sg_fd *sfp;
 333         Sg_request *srp;
 334         int req_pack_id = -1;
 335         sg_io_hdr_t *hp;
 336         struct sg_header *old_hdr = NULL;
 337         int retval = 0;
 338
 339         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 340                 return -ENXIO;
 341         SCSI_LOG_TIMEOUT(3, printk("sg_read: %s, count=%d\n",
 342                                    sdp->disk->disk_name, (int) count));
 343
 344         if (!access_ok(VERIFY_WRITE, buf, count))
 345                 return -EFAULT;
 346         if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
 347                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 348                 if (!old_hdr)
 349                         return -ENOMEM;
 350                 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
 351                         retval = -EFAULT;
 352                         goto free_old_hdr;
 353                 }
 354                 if (old_hdr->reply_len < 0) {
 355                         if (count >= SZ_SG_IO_HDR) {
 356                                 sg_io_hdr_t *new_hdr;
 357                                 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
 358                                 if (!new_hdr) {
 359                                         retval = -ENOMEM;
 360                                         goto free_old_hdr;
 361                                 }
 362                                 retval =__copy_from_user
 363                                     (new_hdr, buf, SZ_SG_IO_HDR);
 364                                 req_pack_id = new_hdr->pack_id;
 365                                 kfree(new_hdr);
 366                                 if (retval) {
 367                                         retval = -EFAULT;
 368                                         goto free_old_hdr;
 369                                 }
 370                         }
 371                 } else
 372                         req_pack_id = old_hdr->pack_id;
 373         }
 374         srp = sg_get_rq_mark(sfp, req_pack_id);
 375         if (!srp) {             /* now wait on packet to arrive */
 376                 if (sdp->detached) {
 377                         retval = -ENODEV;
 378                         goto free_old_hdr;
 379                 }
 380                 if (filp->f_flags & O_NONBLOCK) {
 381                         retval = -EAGAIN;
 382                         goto free_old_hdr;
 383                 }
 384                 while (1) {
 385                         retval = 0; /* following macro beats race condition */
 386                         __wait_event_interruptible(sfp->read_wait,
 387                                 (sdp->detached ||
 388                                 (srp = sg_get_rq_mark(sfp, req_pack_id))),
 389                                 retval);
 390                         if (sdp->detached) {
 391                                 retval = -ENODEV;
 392                                 goto free_old_hdr;
 393                         }
 394                         if (0 == retval)
 395                                 break;
 396
 397                         /* -ERESTARTSYS as signal hit process */
 398                         goto free_old_hdr;
 399                 }
 400         }
 401         if (srp->header.interface_id != '\0') {
 402                 retval = sg_new_read(sfp, buf, count, srp);
 403                 goto free_old_hdr;
 404         }
 405
 406         hp = &srp->header;
 407         if (old_hdr == NULL) {
 408                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 409                 if (! old_hdr) {
 410                         retval = -ENOMEM;
 411                         goto free_old_hdr;
 412                 }
 413         }
 414         memset(old_hdr, 0, SZ_SG_HEADER);
 415         old_hdr->reply_len = (int) hp->timeout;
 416         old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
 417         old_hdr->pack_id = hp->pack_id;
 418         old_hdr->twelve_byte =
 419             ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
 420         old_hdr->target_status = hp->masked_status;
 421         old_hdr->host_status = hp->host_status;
 422         old_hdr->driver_status = hp->driver_status;
 423         if ((CHECK_CONDITION & hp->masked_status) ||
 424             (DRIVER_SENSE & hp->driver_status))
 425                 memcpy(old_hdr->sense_buffer, srp->sense_b,
 426                        sizeof (old_hdr->sense_buffer));
 427         switch (hp->host_status) {
 428         /* This setup of 'result' is for backward compatibility and is best
 429            ignored by the user who should use target, host + driver status */
 430         case DID_OK:
 431         case DID_PASSTHROUGH:
 432         case DID_SOFT_ERROR:
 433                 old_hdr->result = 0;
 434                 break;
 435         case DID_NO_CONNECT:
 436         case DID_BUS_BUSY:
 437         case DID_TIME_OUT:
 438                 old_hdr->result = EBUSY;
 439                 break;
 440         case DID_BAD_TARGET:
 441         case DID_ABORT:
 442         case DID_PARITY:
 443         case DID_RESET:
 444         case DID_BAD_INTR:
 445                 old_hdr->result = EIO;
 446                 break;
 447         case DID_ERROR:
 448                 old_hdr->result = (srp->sense_b[0] == 0 &&
 449                                   hp->masked_status == GOOD) ? 0 : EIO;
 450                 break;
 451         default:
 452                 old_hdr->result = EIO;
 453                 break;
 454         }
 455
 456         /* Now copy the result back to the user buffer.  */
 457         if (count >= SZ_SG_HEADER) {
 458                 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
 459                         retval = -EFAULT;
 460                         goto free_old_hdr;
 461                 }
 462                 buf += SZ_SG_HEADER;
 463                 if (count > old_hdr->reply_len)
 464                         count = old_hdr->reply_len;
 465                 if (count > SZ_SG_HEADER) {
 466                         if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
 467                                 retval = -EFAULT;
 468                                 goto free_old_hdr;
 469                         }
 470                 }
 471         } else
 472                 count = (old_hdr->result == 0) ? 0 : -EIO;
 473         sg_finish_rem_req(srp);
 474         retval = count;
 475 free_old_hdr:
 476         kfree(old_hdr);
 477         return retval;
 478 }
 479
 480 static ssize_t
 481 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
 482 {
 483         sg_io_hdr_t *hp = &srp->header;
 484         int err = 0;
 485         int len;
 486
 487         if (count < SZ_SG_IO_HDR) {
 488                 err = -EINVAL;
 489                 goto err_out;
 490         }
 491         hp->sb_len_wr = 0;
 492         if ((hp->mx_sb_len > 0) && hp->sbp) {
 493                 if ((CHECK_CONDITION & hp->masked_status) ||
 494                     (DRIVER_SENSE & hp->driver_status)) {
 495                         int sb_len = SCSI_SENSE_BUFFERSIZE;
 496                         sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
 497                         len = 8 + (int) srp->sense_b[7];        /* Additional sense length field */
 498                         len = (len > sb_len) ? sb_len : len;
 499                         if (copy_to_user(hp->sbp, srp->sense_b, len)) {
 500                                 err = -EFAULT;
 501                                 goto err_out;
 502                         }
 503                         hp->sb_len_wr = len;
 504                 }
 505         }
 506         if (hp->masked_status || hp->host_status || hp->driver_status)
 507                 hp->info |= SG_INFO_CHECK;
 508         if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
 509                 err = -EFAULT;
 510                 goto err_out;
 511         }
 512         err = sg_read_xfer(srp);
 513       err_out:
 514         sg_finish_rem_req(srp);
 515         return (0 == err) ? count : err;
 516 }
 517
 518 static ssize_t
 519 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
 520 {
 521         int mxsize, cmd_size, k;
 522         int input_size, blocking;
 523         unsigned char opcode;
 524         Sg_device *sdp;
 525         Sg_fd *sfp;
 526         Sg_request *srp;
 527         struct sg_header old_hdr;
 528         sg_io_hdr_t *hp;
 529         unsigned char cmnd[MAX_COMMAND_SIZE];
 530
 531         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 532                 return -ENXIO;
 533         SCSI_LOG_TIMEOUT(3, printk("sg_write: %s, count=%d\n",
 534                                    sdp->disk->disk_name, (int) count));
 535         if (sdp->detached)
 536                 return -ENODEV;
 537         if (!((filp->f_flags & O_NONBLOCK) ||
 538               scsi_block_when_processing_errors(sdp->device)))
 539                 return -ENXIO;
 540
 541         if (!access_ok(VERIFY_READ, buf, count))
 542                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 543         if (count < SZ_SG_HEADER)
 544                 return -EIO;
 545         if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
 546                 return -EFAULT;
 547         blocking = !(filp->f_flags & O_NONBLOCK);
 548         if (old_hdr.reply_len < 0)
 549                 return sg_new_write(sfp, buf, count, blocking, 0, NULL);
 550         if (count < (SZ_SG_HEADER + 6))
 551                 return -EIO;    /* The minimum scsi command length is 6 bytes. */
 552
 553         if (!(srp = sg_add_request(sfp))) {
 554                 SCSI_LOG_TIMEOUT(1, printk("sg_write: queue full\n"));
 555                 return -EDOM;
 556         }
 557         buf += SZ_SG_HEADER;
 558         __get_user(opcode, buf);
 559         if (sfp->next_cmd_len > 0) {
 560                 if (sfp->next_cmd_len > MAX_COMMAND_SIZE) {
 561                         SCSI_LOG_TIMEOUT(1, printk("sg_write: command length too long\n"));
 562                         sfp->next_cmd_len = 0;
 563                         sg_remove_request(sfp, srp);
 564                         return -EIO;
 565                 }
 566                 cmd_size = sfp->next_cmd_len;
 567                 sfp->next_cmd_len = 0;  /* reset so only this write() effected */
 568         } else {
 569                 cmd_size = COMMAND_SIZE(opcode);        /* based on SCSI command group */
 570                 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
 571                         cmd_size = 12;
 572         }
 573         SCSI_LOG_TIMEOUT(4, printk(
 574                 "sg_write:   scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
 575 /* Determine buffer size.  */
 576         input_size = count - cmd_size;
 577         mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
 578         mxsize -= SZ_SG_HEADER;
 579         input_size -= SZ_SG_HEADER;
 580         if (input_size < 0) {
 581                 sg_remove_request(sfp, srp);
 582                 return -EIO;    /* User did not pass enough bytes for this command. */
 583         }
 584         hp = &srp->header;
 585         hp->interface_id = '\0';        /* indicator of old interface tunnelled */
 586         hp->cmd_len = (unsigned char) cmd_size;
 587         hp->iovec_count = 0;
 588         hp->mx_sb_len = 0;
 589         if (input_size > 0)
 590                 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
 591                     SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
 592         else
 593                 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
 594         hp->dxfer_len = mxsize;
 595         hp->dxferp = (char __user *)buf + cmd_size;
 596         hp->sbp = NULL;
 597         hp->timeout = old_hdr.reply_len;        /* structure abuse ... */
 598         hp->flags = input_size; /* structure abuse ... */
 599         hp->pack_id = old_hdr.pack_id;
 600         hp->usr_ptr = NULL;
 601         if (__copy_from_user(cmnd, buf, cmd_size))
 602                 return -EFAULT;
 603         /*
 604          * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
 605          * but is is possible that the app intended SG_DXFER_TO_DEV, because there
 606          * is a non-zero input_size, so emit a warning.
 607          */
 608         if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV)
 609                 if (printk_ratelimit())
 610                         printk(KERN_WARNING
 611                                "sg_write: data in/out %d/%d bytes for SCSI command 0x%x--"
 612                                "guessing data in;\n" KERN_WARNING "   "
 613                                "program %s not setting count and/or reply_len properly\n",
 614                                old_hdr.reply_len - (int)SZ_SG_HEADER,
 615                                input_size, (unsigned int) cmnd[0],
 616                                current->comm);
 617         k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
 618         return (k < 0) ? k : count;
 619 }
 620
 621 static ssize_t
 622 sg_new_write(Sg_fd * sfp, const char __user *buf, size_t count,
 623              int blocking, int read_only, Sg_request ** o_srp)
 624 {
 625         int k;
 626         Sg_request *srp;
 627         sg_io_hdr_t *hp;
 628         unsigned char cmnd[MAX_COMMAND_SIZE];
 629         int timeout;
 630         unsigned long ul_timeout;
 631
 632         if (count < SZ_SG_IO_HDR)
 633                 return -EINVAL;
 634         if (!access_ok(VERIFY_READ, buf, count))
 635                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 636
 637         sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
 638         if (!(srp = sg_add_request(sfp))) {
 639                 SCSI_LOG_TIMEOUT(1, printk("sg_new_write: queue full\n"));
 640                 return -EDOM;
 641         }
 642         hp = &srp->header;
 643         if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
 644                 sg_remove_request(sfp, srp);
 645                 return -EFAULT;
 646         }
 647         if (hp->interface_id != 'S') {
 648                 sg_remove_request(sfp, srp);
 649                 return -ENOSYS;
 650         }
 651         if (hp->flags & SG_FLAG_MMAP_IO) {
 652                 if (hp->dxfer_len > sfp->reserve.bufflen) {
 653                         sg_remove_request(sfp, srp);
 654                         return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
 655                 }
 656                 if (hp->flags & SG_FLAG_DIRECT_IO) {
 657                         sg_remove_request(sfp, srp);
 658                         return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
 659                 }
 660                 if (sg_res_in_use(sfp)) {
 661                         sg_remove_request(sfp, srp);
 662                         return -EBUSY;  /* reserve buffer already being used */
 663                 }
 664         }
 665         ul_timeout = msecs_to_jiffies(srp->header.timeout);
 666         timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
 667         if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
 668                 sg_remove_request(sfp, srp);
 669                 return -EMSGSIZE;
 670         }
 671         if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
 672                 sg_remove_request(sfp, srp);
 673                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 674         }
 675         if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
 676                 sg_remove_request(sfp, srp);
 677                 return -EFAULT;
 678         }
 679         if (read_only &&
 680             (!sg_allow_access(cmnd[0], sfp->parentdp->device->type))) {
 681                 sg_remove_request(sfp, srp);
 682                 return -EPERM;
 683         }
 684         k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
 685         if (k < 0)
 686                 return k;
 687         if (o_srp)
 688                 *o_srp = srp;
 689         return count;
 690 }
 691
 692 static int
 693 sg_common_write(Sg_fd * sfp, Sg_request * srp,
 694                 unsigned char *cmnd, int timeout, int blocking)
 695 {
 696         int k, data_dir;
 697         Sg_device *sdp = sfp->parentdp;
 698         sg_io_hdr_t *hp = &srp->header;
 699
 700         srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
 701         hp->status = 0;
 702         hp->masked_status = 0;
 703         hp->msg_status = 0;
 704         hp->info = 0;
 705         hp->host_status = 0;
 706         hp->driver_status = 0;
 707         hp->resid = 0;
 708         SCSI_LOG_TIMEOUT(4, printk("sg_common_write:  scsi opcode=0x%02x, cmd_size=%d\n",
 709                           (int) cmnd[0], (int) hp->cmd_len));
 710
 711         if ((k = sg_start_req(srp))) {
 712                 SCSI_LOG_TIMEOUT(1, printk("sg_common_write: start_req err=%d\n", k));
 713                 sg_finish_rem_req(srp);
 714                 return k;       /* probably out of space --> ENOMEM */
 715         }
 716         if ((k = sg_write_xfer(srp))) {
 717                 SCSI_LOG_TIMEOUT(1, printk("sg_common_write: write_xfer, bad address\n"));
 718                 sg_finish_rem_req(srp);
 719                 return k;
 720         }
 721         if (sdp->detached) {
 722                 sg_finish_rem_req(srp);
 723                 return -ENODEV;
 724         }
 725
 726         switch (hp->dxfer_direction) {
 727         case SG_DXFER_TO_FROM_DEV:
 728         case SG_DXFER_FROM_DEV:
 729                 data_dir = DMA_FROM_DEVICE;
 730                 break;
 731         case SG_DXFER_TO_DEV:
 732                 data_dir = DMA_TO_DEVICE;
 733                 break;
 734         case SG_DXFER_UNKNOWN:
 735                 data_dir = DMA_BIDIRECTIONAL;
 736                 break;
 737         default:
 738                 data_dir = DMA_NONE;
 739                 break;
 740         }
 741         hp->duration = jiffies_to_msecs(jiffies);
 742 /* Now send everything of to mid-level. The next time we hear about this
 743    packet is when sg_cmd_done() is called (i.e. a callback). */
 744         if (scsi_execute_async(sdp->device, cmnd, hp->cmd_len, data_dir, srp->data.buffer,
 745                                 hp->dxfer_len, srp->data.k_use_sg, timeout,
 746                                 SG_DEFAULT_RETRIES, srp, sg_cmd_done,
 747                                 GFP_ATOMIC)) {
 748                 SCSI_LOG_TIMEOUT(1, printk("sg_common_write: scsi_execute_async failed\n"));
 749                 /*
 750                  * most likely out of mem, but could also be a bad map
 751                  */
 752                 sg_finish_rem_req(srp);
 753                 return -ENOMEM;
 754         } else
 755                 return 0;
 756 }
 757
 758 static int
 759 sg_srp_done(Sg_request *srp, Sg_fd *sfp)
 760 {
 761         unsigned long iflags;
 762         int done;
 763
 764         read_lock_irqsave(&sfp->rq_list_lock, iflags);
 765         done = srp->done;
 766         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 767         return done;
 768 }
 769
 770 static int
 771 sg_ioctl(struct inode *inode, struct file *filp,
 772          unsigned int cmd_in, unsigned long arg)
 773 {
 774         void __user *p = (void __user *)arg;
 775         int __user *ip = p;
 776         int result, val, read_only;
 777         Sg_device *sdp;
 778         Sg_fd *sfp;
 779         Sg_request *srp;
 780         unsigned long iflags;
 781
 782         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 783                 return -ENXIO;
 784         SCSI_LOG_TIMEOUT(3, printk("sg_ioctl: %s, cmd=0x%x\n",
 785                                    sdp->disk->disk_name, (int) cmd_in));
 786         read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
 787
 788         switch (cmd_in) {
 789         case SG_IO:
 790                 {
 791                         int blocking = 1;       /* ignore O_NONBLOCK flag */
 792
 793                         if (sdp->detached)
 794                                 return -ENODEV;
 795                         if (!scsi_block_when_processing_errors(sdp->device))
 796                                 return -ENXIO;
 797                         if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
 798                                 return -EFAULT;
 799                         result =
 800                             sg_new_write(sfp, p, SZ_SG_IO_HDR,
 801                                          blocking, read_only, &srp);
 802                         if (result < 0)
 803                                 return result;
 804                         srp->sg_io_owned = 1;
 805                         while (1) {
 806                                 result = 0;     /* following macro to beat race condition */
 807                                 __wait_event_interruptible(sfp->read_wait,
 808                                         (sdp->detached || sfp->closed || sg_srp_done(srp, sfp)),
 809                                                            result);
 810                                 if (sdp->detached)
 811                                         return -ENODEV;
 812                                 if (sfp->closed)
 813                                         return 0;       /* request packet dropped already */
 814                                 if (0 == result)
 815                                         break;
 816                                 srp->orphan = 1;
 817                                 return result;  /* -ERESTARTSYS because signal hit process */
 818                         }
 819                         write_lock_irqsave(&sfp->rq_list_lock, iflags);
 820                         srp->done = 2;
 821                         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 822                         result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
 823                         return (result < 0) ? result : 0;
 824                 }
 825         case SG_SET_TIMEOUT:
 826                 result = get_user(val, ip);
 827                 if (result)
 828                         return result;
 829                 if (val < 0)
 830                         return -EIO;
 831                 if (val >= MULDIV (INT_MAX, USER_HZ, HZ))
 832                     val = MULDIV (INT_MAX, USER_HZ, HZ);
 833                 sfp->timeout_user = val;
 834                 sfp->timeout = MULDIV (val, HZ, USER_HZ);
 835
 836                 return 0;
 837         case SG_GET_TIMEOUT:    /* N.B. User receives timeout as return value */
 838                                 /* strange ..., for backward compatibility */
 839                 return sfp->timeout_user;
 840         case SG_SET_FORCE_LOW_DMA:
 841                 result = get_user(val, ip);
 842                 if (result)
 843                         return result;
 844                 if (val) {
 845                         sfp->low_dma = 1;
 846                         if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
 847                                 val = (int) sfp->reserve.bufflen;
 848                                 sg_remove_scat(&sfp->reserve);
 849                                 sg_build_reserve(sfp, val);
 850                         }
 851                 } else {
 852                         if (sdp->detached)
 853                                 return -ENODEV;
 854                         sfp->low_dma = sdp->device->host->unchecked_isa_dma;
 855                 }
 856                 return 0;
 857         case SG_GET_LOW_DMA:
 858                 return put_user((int) sfp->low_dma, ip);
 859         case SG_GET_SCSI_ID:
 860                 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
 861                         return -EFAULT;
 862                 else {
 863                         sg_scsi_id_t __user *sg_idp = p;
 864
 865                         if (sdp->detached)
 866                                 return -ENODEV;
 867                         __put_user((int) sdp->device->host->host_no,
 868                                    &sg_idp->host_no);
 869                         __put_user((int) sdp->device->channel,
 870                                    &sg_idp->channel);
 871                         __put_user((int) sdp->device->id, &sg_idp->scsi_id);
 872                         __put_user((int) sdp->device->lun, &sg_idp->lun);
 873                         __put_user((int) sdp->device->type, &sg_idp->scsi_type);
 874                         __put_user((short) sdp->device->host->cmd_per_lun,
 875                                    &sg_idp->h_cmd_per_lun);
 876                         __put_user((short) sdp->device->queue_depth,
 877                                    &sg_idp->d_queue_depth);
 878                         __put_user(0, &sg_idp->unused[0]);
 879                         __put_user(0, &sg_idp->unused[1]);
 880                         return 0;
 881                 }
 882         case SG_SET_FORCE_PACK_ID:
 883                 result = get_user(val, ip);
 884                 if (result)
 885                         return result;
 886                 sfp->force_packid = val ? 1 : 0;
 887                 return 0;
 888         case SG_GET_PACK_ID:
 889                 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
 890                         return -EFAULT;
 891                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 892                 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
 893                         if ((1 == srp->done) && (!srp->sg_io_owned)) {
 894                                 read_unlock_irqrestore(&sfp->rq_list_lock,
 895                                                        iflags);
 896                                 __put_user(srp->header.pack_id, ip);
 897                                 return 0;
 898                         }
 899                 }
 900                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 901                 __put_user(-1, ip);
 902                 return 0;
 903         case SG_GET_NUM_WAITING:
 904                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 905                 for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) {
 906                         if ((1 == srp->done) && (!srp->sg_io_owned))
 907                                 ++val;
 908                 }
 909                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 910                 return put_user(val, ip);
 911         case SG_GET_SG_TABLESIZE:
 912                 return put_user(sdp->sg_tablesize, ip);
 913         case SG_SET_RESERVED_SIZE:
 914                 result = get_user(val, ip);
 915                 if (result)
 916                         return result;
 917                 if (val < 0)
 918                         return -EINVAL;
 919                 val = min_t(int, val,
 920                                 sdp->device->request_queue->max_sectors * 512);
 921                 if (val != sfp->reserve.bufflen) {
 922                         if (sg_res_in_use(sfp) || sfp->mmap_called)
 923                                 return -EBUSY;
 924                         sg_remove_scat(&sfp->reserve);
 925                         sg_build_reserve(sfp, val);
 926                 }
 927                 return 0;
 928         case SG_GET_RESERVED_SIZE:
 929                 val = min_t(int, sfp->reserve.bufflen,
 930                                 sdp->device->request_queue->max_sectors * 512);
 931                 return put_user(val, ip);
 932         case SG_SET_COMMAND_Q:
 933                 result = get_user(val, ip);
 934                 if (result)
 935                         return result;
 936                 sfp->cmd_q = val ? 1 : 0;
 937                 return 0;
 938         case SG_GET_COMMAND_Q:
 939                 return put_user((int) sfp->cmd_q, ip);
 940         case SG_SET_KEEP_ORPHAN:
 941                 result = get_user(val, ip);
 942                 if (result)
 943                         return result;
 944                 sfp->keep_orphan = val;
 945                 return 0;
 946         case SG_GET_KEEP_ORPHAN:
 947                 return put_user((int) sfp->keep_orphan, ip);
 948         case SG_NEXT_CMD_LEN:
 949                 result = get_user(val, ip);
 950                 if (result)
 951                         return result;
 952                 sfp->next_cmd_len = (val > 0) ? val : 0;
 953                 return 0;
 954         case SG_GET_VERSION_NUM:
 955                 return put_user(sg_version_num, ip);
 956         case SG_GET_ACCESS_COUNT:
 957                 /* faked - we don't have a real access count anymore */
 958                 val = (sdp->device ? 1 : 0);
 959                 return put_user(val, ip);
 960         case SG_GET_REQUEST_TABLE:
 961                 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
 962                         return -EFAULT;
 963                 else {
 964                         sg_req_info_t *rinfo;
 965                         unsigned int ms;
 966
 967                         rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
 968                                                                 GFP_KERNEL);
 969                         if (!rinfo)
 970                                 return -ENOMEM;
 971                         read_lock_irqsave(&sfp->rq_list_lock, iflags);
 972                         for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE;
 973                              ++val, srp = srp ? srp->nextrp : srp) {
 974                                 memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
 975                                 if (srp) {
 976                                         rinfo[val].req_state = srp->done + 1;
 977                                         rinfo[val].problem =
 978                                             srp->header.masked_status &
 979                                             srp->header.host_status &
 980                                             srp->header.driver_status;
 981                                         if (srp->done)
 982                                                 rinfo[val].duration =
 983                                                         srp->header.duration;
 984                                         else {
 985                                                 ms = jiffies_to_msecs(jiffies);
 986                                                 rinfo[val].duration =
 987                                                     (ms > srp->header.duration) ?
 988                                                     (ms - srp->header.duration) : 0;
 989                                         }
 990                                         rinfo[val].orphan = srp->orphan;
 991                                         rinfo[val].sg_io_owned =
 992                                                         srp->sg_io_owned;
 993                                         rinfo[val].pack_id =
 994                                                         srp->header.pack_id;
 995                                         rinfo[val].usr_ptr =
 996                                                         srp->header.usr_ptr;
 997                                 }
 998                         }
 999                         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1000                         result = __copy_to_user(p, rinfo,
1001                                                 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1002                         result = result ? -EFAULT : 0;
1003                         kfree(rinfo);
1004                         return result;
1005                 }
1006         case SG_EMULATED_HOST:
1007                 if (sdp->detached)
1008                         return -ENODEV;
1009                 return put_user(sdp->device->host->hostt->emulated, ip);
1010         case SG_SCSI_RESET:
1011                 if (sdp->detached)
1012                         return -ENODEV;
1013                 if (filp->f_flags & O_NONBLOCK) {
1014                         if (scsi_host_in_recovery(sdp->device->host))
1015                                 return -EBUSY;
1016                 } else if (!scsi_block_when_processing_errors(sdp->device))
1017                         return -EBUSY;
1018                 result = get_user(val, ip);
1019                 if (result)
1020                         return result;
1021                 if (SG_SCSI_RESET_NOTHING == val)
1022                         return 0;
1023                 switch (val) {
1024                 case SG_SCSI_RESET_DEVICE:
1025                         val = SCSI_TRY_RESET_DEVICE;
1026                         break;
1027                 case SG_SCSI_RESET_BUS:
1028                         val = SCSI_TRY_RESET_BUS;
1029                         break;
1030                 case SG_SCSI_RESET_HOST:
1031                         val = SCSI_TRY_RESET_HOST;
1032                         break;
1033                 default:
1034                         return -EINVAL;
1035                 }
1036                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1037                         return -EACCES;
1038                 return (scsi_reset_provider(sdp->device, val) ==
1039                         SUCCESS) ? 0 : -EIO;
1040         case SCSI_IOCTL_SEND_COMMAND:
1041                 if (sdp->detached)
1042                         return -ENODEV;
1043                 if (read_only) {
1044                         unsigned char opcode = WRITE_6;
1045                         Scsi_Ioctl_Command __user *siocp = p;
1046
1047                         if (copy_from_user(&opcode, siocp->data, 1))
1048                                 return -EFAULT;
1049                         if (!sg_allow_access(opcode, sdp->device->type))
1050                                 return -EPERM;
1051                 }
1052                 return sg_scsi_ioctl(filp, sdp->device->request_queue, NULL, p);
1053         case SG_SET_DEBUG:
1054                 result = get_user(val, ip);
1055                 if (result)
1056                         return result;
1057                 sdp->sgdebug = (char) val;
1058                 return 0;
1059         case SCSI_IOCTL_GET_IDLUN:
1060         case SCSI_IOCTL_GET_BUS_NUMBER:
1061         case SCSI_IOCTL_PROBE_HOST:
1062         case SG_GET_TRANSFORM:
1063                 if (sdp->detached)
1064                         return -ENODEV;
1065                 return scsi_ioctl(sdp->device, cmd_in, p);
1066         case BLKSECTGET:
1067                 return put_user(sdp->device->request_queue->max_sectors * 512,
1068                                 ip);
1069         default:
1070                 if (read_only)
1071                         return -EPERM;  /* don't know so take safe approach */
1072                 return scsi_ioctl(sdp->device, cmd_in, p);
1073         }
1074 }
1075
1076 #ifdef CONFIG_COMPAT
1077 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1078 {
1079         Sg_device *sdp;
1080         Sg_fd *sfp;
1081         struct scsi_device *sdev;
1082
1083         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1084                 return -ENXIO;
1085
1086         sdev = sdp->device;
1087         if (sdev->host->hostt->compat_ioctl) {
1088                 int ret;
1089
1090                 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1091
1092                 return ret;
1093         }
1094
1095         return -ENOIOCTLCMD;
1096 }
1097 #endif
1098
1099 static unsigned int
1100 sg_poll(struct file *filp, poll_table * wait)
1101 {
1102         unsigned int res = 0;
1103         Sg_device *sdp;
1104         Sg_fd *sfp;
1105         Sg_request *srp;
1106         int count = 0;
1107         unsigned long iflags;
1108
1109         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))
1110             || sfp->closed)
1111                 return POLLERR;
1112         poll_wait(filp, &sfp->read_wait, wait);
1113         read_lock_irqsave(&sfp->rq_list_lock, iflags);
1114         for (srp = sfp->headrp; srp; srp = srp->nextrp) {
1115                 /* if any read waiting, flag it */
1116                 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1117                         res = POLLIN | POLLRDNORM;
1118                 ++count;
1119         }
1120         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1121
1122         if (sdp->detached)
1123                 res |= POLLHUP;
1124         else if (!sfp->cmd_q) {
1125                 if (0 == count)
1126                         res |= POLLOUT | POLLWRNORM;
1127         } else if (count < SG_MAX_QUEUE)
1128                 res |= POLLOUT | POLLWRNORM;
1129         SCSI_LOG_TIMEOUT(3, printk("sg_poll: %s, res=0x%x\n",
1130                                    sdp->disk->disk_name, (int) res));
1131         return res;
1132 }
1133
1134 static int
1135 sg_fasync(int fd, struct file *filp, int mode)
1136 {
1137         int retval;
1138         Sg_device *sdp;
1139         Sg_fd *sfp;
1140
1141         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1142                 return -ENXIO;
1143         SCSI_LOG_TIMEOUT(3, printk("sg_fasync: %s, mode=%d\n",
1144                                    sdp->disk->disk_name, mode));
1145
1146         retval = fasync_helper(fd, filp, mode, &sfp->async_qp);
1147         return (retval < 0) ? retval : 0;
1148 }
1149
1150 static struct page *
1151 sg_vma_nopage(struct vm_area_struct *vma, unsigned long addr, int *type)
1152 {
1153         Sg_fd *sfp;
1154         struct page *page = NOPAGE_SIGBUS;
1155         unsigned long offset, len, sa;
1156         Sg_scatter_hold *rsv_schp;
1157         struct scatterlist *sg;
1158         int k;
1159
1160         if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1161                 return page;
1162         rsv_schp = &sfp->reserve;
1163         offset = addr - vma->vm_start;
1164         if (offset >= rsv_schp->bufflen)
1165                 return page;
1166         SCSI_LOG_TIMEOUT(3, printk("sg_vma_nopage: offset=%lu, scatg=%d\n",
1167                                    offset, rsv_schp->k_use_sg));
1168         sg = rsv_schp->buffer;
1169         sa = vma->vm_start;
1170         for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
1171              ++k, ++sg) {
1172                 len = vma->vm_end - sa;
1173                 len = (len < sg->length) ? len : sg->length;
1174                 if (offset < len) {
1175                         page = virt_to_page(page_address(sg->page) + offset);
1176                         get_page(page); /* increment page count */
1177                         break;
1178                 }
1179                 sa += len;
1180                 offset -= len;
1181         }
1182
1183         if (type)
1184                 *type = VM_FAULT_MINOR;
1185         return page;
1186 }
1187
1188 static struct vm_operations_struct sg_mmap_vm_ops = {
1189         .nopage = sg_vma_nopage,
1190 };
1191
1192 static int
1193 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1194 {
1195         Sg_fd *sfp;
1196         unsigned long req_sz, len, sa;
1197         Sg_scatter_hold *rsv_schp;
1198         int k;
1199         struct scatterlist *sg;
1200
1201         if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1202                 return -ENXIO;
1203         req_sz = vma->vm_end - vma->vm_start;
1204         SCSI_LOG_TIMEOUT(3, printk("sg_mmap starting, vm_start=%p, len=%d\n",
1205                                    (void *) vma->vm_start, (int) req_sz));
1206         if (vma->vm_pgoff)
1207                 return -EINVAL; /* want no offset */
1208         rsv_schp = &sfp->reserve;
1209         if (req_sz > rsv_schp->bufflen)
1210                 return -ENOMEM; /* cannot map more than reserved buffer */
1211
1212         sa = vma->vm_start;
1213         sg = rsv_schp->buffer;
1214         for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
1215              ++k, ++sg) {
1216                 len = vma->vm_end - sa;
1217                 len = (len < sg->length) ? len : sg->length;
1218                 sa += len;
1219         }
1220
1221         sfp->mmap_called = 1;
1222         vma->vm_flags |= VM_RESERVED;
1223         vma->vm_private_data = sfp;
1224         vma->vm_ops = &sg_mmap_vm_ops;
1225         return 0;
1226 }
1227
1228 /* This function is a "bottom half" handler that is called by the
1229  * mid level when a command is completed (or has failed). */
1230 static void
1231 sg_cmd_done(void *data, char *sense, int result, int resid)
1232 {
1233         Sg_request *srp = data;
1234         Sg_device *sdp = NULL;
1235         Sg_fd *sfp;
1236         unsigned long iflags;
1237         unsigned int ms;
1238
1239         if (NULL == srp) {
1240                 printk(KERN_ERR "sg_cmd_done: NULL request\n");
1241                 return;
1242         }
1243         sfp = srp->parentfp;
1244         if (sfp)
1245                 sdp = sfp->parentdp;
1246         if ((NULL == sdp) || sdp->detached) {
1247                 printk(KERN_INFO "sg_cmd_done: device detached\n");
1248                 return;
1249         }
1250
1251
1252         SCSI_LOG_TIMEOUT(4, printk("sg_cmd_done: %s, pack_id=%d, res=0x%x\n",
1253                 sdp->disk->disk_name, srp->header.pack_id, result));
1254         srp->header.resid = resid;
1255         ms = jiffies_to_msecs(jiffies);
1256         srp->header.duration = (ms > srp->header.duration) ?
1257                                 (ms - srp->header.duration) : 0;
1258         if (0 != result) {
1259                 struct scsi_sense_hdr sshdr;
1260
1261                 memcpy(srp->sense_b, sense, sizeof (srp->sense_b));
1262                 srp->header.status = 0xff & result;
1263                 srp->header.masked_status = status_byte(result);
1264                 srp->header.msg_status = msg_byte(result);
1265                 srp->header.host_status = host_byte(result);
1266                 srp->header.driver_status = driver_byte(result);
1267                 if ((sdp->sgdebug > 0) &&
1268                     ((CHECK_CONDITION == srp->header.masked_status) ||
1269                      (COMMAND_TERMINATED == srp->header.masked_status)))
1270                         __scsi_print_sense("sg_cmd_done", sense,
1271                                            SCSI_SENSE_BUFFERSIZE);
1272
1273                 /* Following if statement is a patch supplied by Eric Youngdale */
1274                 if (driver_byte(result) != 0
1275                     && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1276                     && !scsi_sense_is_deferred(&sshdr)
1277                     && sshdr.sense_key == UNIT_ATTENTION
1278                     && sdp->device->removable) {
1279                         /* Detected possible disc change. Set the bit - this */
1280                         /* may be used if there are filesystems using this device */
1281                         sdp->device->changed = 1;
1282                 }
1283         }
1284         /* Rely on write phase to clean out srp status values, so no "else" */
1285
1286         if (sfp->closed) {      /* whoops this fd already released, cleanup */
1287                 SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, freeing ...\n"));
1288                 sg_finish_rem_req(srp);
1289                 srp = NULL;
1290                 if (NULL == sfp->headrp) {
1291                         SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, final cleanup\n"));
1292                         if (0 == sg_remove_sfp(sdp, sfp)) {     /* device still present */
1293                                 scsi_device_put(sdp->device);
1294                         }
1295                         sfp = NULL;
1296                 }
1297         } else if (srp && srp->orphan) {
1298                 if (sfp->keep_orphan)
1299                         srp->sg_io_owned = 0;
1300                 else {
1301                         sg_finish_rem_req(srp);
1302                         srp = NULL;
1303                 }
1304         }
1305         if (sfp && srp) {
1306                 /* Now wake up any sg_read() that is waiting for this packet. */
1307                 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1308                 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1309                 srp->done = 1;
1310                 wake_up_interruptible(&sfp->read_wait);
1311                 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1312         }
1313 }
1314
1315 static struct file_operations sg_fops = {
1316         .owner = THIS_MODULE,
1317         .read = sg_read,
1318         .write = sg_write,
1319         .poll = sg_poll,
1320         .ioctl = sg_ioctl,
1321 #ifdef CONFIG_COMPAT
1322         .compat_ioctl = sg_compat_ioctl,
1323 #endif
1324         .open = sg_open,
1325         .mmap = sg_mmap,
1326         .release = sg_release,
1327         .fasync = sg_fasync,
1328 };
1329
1330 static struct class *sg_sysfs_class;
1331
1332 static int sg_sysfs_valid = 0;
1333
1334 static int sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1335 {
1336         struct request_queue *q = scsidp->request_queue;
1337         Sg_device *sdp;
1338         unsigned long iflags;
1339         void *old_sg_dev_arr = NULL;
1340         int k, error;
1341
1342         sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1343         if (!sdp) {
1344                 printk(KERN_WARNING "kmalloc Sg_device failure\n");
1345                 return -ENOMEM;
1346         }
1347
1348         write_lock_irqsave(&sg_dev_arr_lock, iflags);
1349         if (unlikely(sg_nr_dev >= sg_dev_max)) {        /* try to resize */
1350                 Sg_device **tmp_da;
1351                 int tmp_dev_max = sg_nr_dev + SG_DEV_ARR_LUMP;
1352                 write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1353
1354                 tmp_da = kzalloc(tmp_dev_max * sizeof(Sg_device *), GFP_KERNEL);
1355                 if (unlikely(!tmp_da))
1356                         goto expand_failed;
1357
1358                 write_lock_irqsave(&sg_dev_arr_lock, iflags);
1359                 memcpy(tmp_da, sg_dev_arr, sg_dev_max * sizeof(Sg_device *));
1360                 old_sg_dev_arr = sg_dev_arr;
1361                 sg_dev_arr = tmp_da;
1362                 sg_dev_max = tmp_dev_max;
1363         }
1364
1365         for (k = 0; k < sg_dev_max; k++)
1366                 if (!sg_dev_arr[k])
1367                         break;
1368         if (unlikely(k >= SG_MAX_DEVS))
1369                 goto overflow;
1370
1371         SCSI_LOG_TIMEOUT(3, printk("sg_alloc: dev=%d \n", k));
1372         sprintf(disk->disk_name, "sg%d", k);
1373         disk->first_minor = k;
1374         sdp->disk = disk;
1375         sdp->device = scsidp;
1376         init_waitqueue_head(&sdp->o_excl_wait);
1377         sdp->sg_tablesize = min(q->max_hw_segments, q->max_phys_segments);
1378
1379         sg_nr_dev++;
1380         sg_dev_arr[k] = sdp;
1381         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1382         error = k;
1383
1384  out:
1385         if (error < 0)
1386                 kfree(sdp);
1387         kfree(old_sg_dev_arr);
1388         return error;
1389
1390  expand_failed:
1391         printk(KERN_WARNING "sg_alloc: device array cannot be resized\n");
1392         error = -ENOMEM;
1393         goto out;
1394
1395  overflow:
1396         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1397         sdev_printk(KERN_WARNING, scsidp,
1398                     "Unable to attach sg device type=%d, minor "
1399                     "number exceeds %d\n", scsidp->type, SG_MAX_DEVS - 1);
1400         error = -ENODEV;
1401         goto out;
1402 }
1403
1404 static int
1405 sg_add(struct class_device *cl_dev, struct class_interface *cl_intf)
1406 {
1407         struct scsi_device *scsidp = to_scsi_device(cl_dev->dev);
1408         struct gendisk *disk;
1409         Sg_device *sdp = NULL;
1410         struct cdev * cdev = NULL;
1411         int error, k;
1412         unsigned long iflags;
1413
1414         disk = alloc_disk(1);
1415         if (!disk) {
1416                 printk(KERN_WARNING "alloc_disk failed\n");
1417                 return -ENOMEM;
1418         }
1419         disk->major = SCSI_GENERIC_MAJOR;
1420
1421         error = -ENOMEM;
1422         cdev = cdev_alloc();
1423         if (!cdev) {
1424                 printk(KERN_WARNING "cdev_alloc failed\n");
1425                 goto out;
1426         }
1427         cdev->owner = THIS_MODULE;
1428         cdev->ops = &sg_fops;
1429
1430         error = sg_alloc(disk, scsidp);
1431         if (error < 0) {
1432                 printk(KERN_WARNING "sg_alloc failed\n");
1433                 goto out;
1434         }
1435         k = error;
1436         sdp = sg_dev_arr[k];
1437
1438         error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, k), 1);
1439         if (error)
1440                 goto cdev_add_err;
1441
1442         sdp->cdev = cdev;
1443         if (sg_sysfs_valid) {
1444                 struct class_device * sg_class_member;
1445
1446                 sg_class_member = class_device_create(sg_sysfs_class, NULL,
1447                                 MKDEV(SCSI_GENERIC_MAJOR, k),
1448                                 cl_dev->dev, "%s",
1449                                 disk->disk_name);
1450                 if (IS_ERR(sg_class_member))
1451                         printk(KERN_WARNING "sg_add: "
1452                                 "class_device_create failed\n");
1453                 class_set_devdata(sg_class_member, sdp);
1454                 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1455                                           &sg_class_member->kobj, "generic");
1456                 if (error)
1457                         printk(KERN_ERR "sg_add: unable to make symlink "
1458                                         "'generic' back to sg%d\n", k);
1459         } else
1460                 printk(KERN_WARNING "sg_add: sg_sys INvalid\n");
1461
1462         sdev_printk(KERN_NOTICE, scsidp,
1463                     "Attached scsi generic sg%d type %d\n", k,scsidp->type);
1464
1465         return 0;
1466
1467 cdev_add_err:
1468         write_lock_irqsave(&sg_dev_arr_lock, iflags);
1469         kfree(sg_dev_arr[k]);
1470         sg_dev_arr[k] = NULL;
1471         sg_nr_dev--;
1472         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1473
1474 out:
1475         put_disk(disk);
1476         if (cdev)
1477                 cdev_del(cdev);
1478         return error;
1479 }
1480
1481 static void
1482 sg_remove(struct class_device *cl_dev, struct class_interface *cl_intf)
1483 {
1484         struct scsi_device *scsidp = to_scsi_device(cl_dev->dev);
1485         Sg_device *sdp = NULL;
1486         unsigned long iflags;
1487         Sg_fd *sfp;
1488         Sg_fd *tsfp;
1489         Sg_request *srp;
1490         Sg_request *tsrp;
1491         int k, delay;
1492
1493         if (NULL == sg_dev_arr)
1494                 return;
1495         delay = 0;
1496         write_lock_irqsave(&sg_dev_arr_lock, iflags);
1497         for (k = 0; k < sg_dev_max; k++) {
1498                 sdp = sg_dev_arr[k];
1499                 if ((NULL == sdp) || (sdp->device != scsidp))
1500                         continue;       /* dirty but lowers nesting */
1501                 if (sdp->headfp) {
1502                         sdp->detached = 1;
1503                         for (sfp = sdp->headfp; sfp; sfp = tsfp) {
1504                                 tsfp = sfp->nextfp;
1505                                 for (srp = sfp->headrp; srp; srp = tsrp) {
1506                                         tsrp = srp->nextrp;
1507                                         if (sfp->closed || (0 == sg_srp_done(srp, sfp)))
1508                                                 sg_finish_rem_req(srp);
1509                                 }
1510                                 if (sfp->closed) {
1511                                         scsi_device_put(sdp->device);
1512                                         __sg_remove_sfp(sdp, sfp);
1513                                 } else {
1514                                         delay = 1;
1515                                         wake_up_interruptible(&sfp->read_wait);
1516                                         kill_fasync(&sfp->async_qp, SIGPOLL,
1517                                                     POLL_HUP);
1518                                 }
1519                         }
1520                         SCSI_LOG_TIMEOUT(3, printk("sg_remove: dev=%d, dirty\n", k));
1521                         if (NULL == sdp->headfp) {
1522                                 sg_dev_arr[k] = NULL;
1523                         }
1524                 } else {        /* nothing active, simple case */
1525                         SCSI_LOG_TIMEOUT(3, printk("sg_remove: dev=%d\n", k));
1526                         sg_dev_arr[k] = NULL;
1527                 }
1528                 sg_nr_dev--;
1529                 break;
1530         }
1531         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1532
1533         if (sdp) {
1534                 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1535                 class_device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, k));
1536                 cdev_del(sdp->cdev);
1537                 sdp->cdev = NULL;
1538                 put_disk(sdp->disk);
1539                 sdp->disk = NULL;
1540                 if (NULL == sdp->headfp)
1541                         kfree((char *) sdp);
1542         }
1543
1544         if (delay)
1545                 msleep(10);     /* dirty detach so delay device destruction */
1546 }
1547
1548 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1549 module_param_named(def_reserved_size, def_reserved_size, int,
1550                    S_IRUGO | S_IWUSR);
1551 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1552
1553 MODULE_AUTHOR("Douglas Gilbert");
1554 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1555 MODULE_LICENSE("GPL");
1556 MODULE_VERSION(SG_VERSION_STR);
1557 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1558
1559 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1560                 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1561 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1562 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1563
1564 static int __init
1565 init_sg(void)
1566 {
1567         int rc;
1568
1569         if (scatter_elem_sz < PAGE_SIZE) {
1570                 scatter_elem_sz = PAGE_SIZE;
1571                 scatter_elem_sz_prev = scatter_elem_sz;
1572         }
1573         if (def_reserved_size >= 0)
1574                 sg_big_buff = def_reserved_size;
1575         else
1576                 def_reserved_size = sg_big_buff;
1577
1578         rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1579                                     SG_MAX_DEVS, "sg");
1580         if (rc)
1581                 return rc;
1582         sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1583         if ( IS_ERR(sg_sysfs_class) ) {
1584                 rc = PTR_ERR(sg_sysfs_class);
1585                 goto err_out;
1586         }
1587         sg_sysfs_valid = 1;
1588         rc = scsi_register_interface(&sg_interface);
1589         if (0 == rc) {
1590 #ifdef CONFIG_SCSI_PROC_FS
1591                 sg_proc_init();
1592 #endif                          /* CONFIG_SCSI_PROC_FS */
1593                 return 0;
1594         }
1595         class_destroy(sg_sysfs_class);
1596 err_out:
1597         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1598         return rc;
1599 }
1600
1601 static void __exit
1602 exit_sg(void)
1603 {
1604 #ifdef CONFIG_SCSI_PROC_FS
1605         sg_proc_cleanup();
1606 #endif                          /* CONFIG_SCSI_PROC_FS */
1607         scsi_unregister_interface(&sg_interface);
1608         class_destroy(sg_sysfs_class);
1609         sg_sysfs_valid = 0;
1610         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1611                                  SG_MAX_DEVS);
1612         kfree((char *)sg_dev_arr);
1613         sg_dev_arr = NULL;
1614         sg_dev_max = 0;
1615 }
1616
1617 static int
1618 sg_start_req(Sg_request * srp)
1619 {
1620         int res;
1621         Sg_fd *sfp = srp->parentfp;
1622         sg_io_hdr_t *hp = &srp->header;
1623         int dxfer_len = (int) hp->dxfer_len;
1624         int dxfer_dir = hp->dxfer_direction;
1625         Sg_scatter_hold *req_schp = &srp->data;
1626         Sg_scatter_hold *rsv_schp = &sfp->reserve;
1627
1628         SCSI_LOG_TIMEOUT(4, printk("sg_start_req: dxfer_len=%d\n", dxfer_len));
1629         if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1630                 return 0;
1631         if (sg_allow_dio && (hp->flags & SG_FLAG_DIRECT_IO) &&
1632             (dxfer_dir != SG_DXFER_UNKNOWN) && (0 == hp->iovec_count) &&
1633             (!sfp->parentdp->device->host->unchecked_isa_dma)) {
1634                 res = sg_build_direct(srp, sfp, dxfer_len);
1635                 if (res <= 0)   /* -ve -> error, 0 -> done, 1 -> try indirect */
1636                         return res;
1637         }
1638         if ((!sg_res_in_use(sfp)) && (dxfer_len <= rsv_schp->bufflen))
1639                 sg_link_reserve(sfp, srp, dxfer_len);
1640         else {
1641                 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1642                 if (res) {
1643                         sg_remove_scat(req_schp);
1644                         return res;
1645                 }
1646         }
1647         return 0;
1648 }
1649
1650 static void
1651 sg_finish_rem_req(Sg_request * srp)
1652 {
1653         Sg_fd *sfp = srp->parentfp;
1654         Sg_scatter_hold *req_schp = &srp->data;
1655
1656         SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n", (int) srp->res_used));
1657         if (srp->res_used)
1658                 sg_unlink_reserve(sfp, srp);
1659         else
1660                 sg_remove_scat(req_schp);
1661         sg_remove_request(sfp, srp);
1662 }
1663
1664 static int
1665 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1666 {
1667         int sg_bufflen = tablesize * sizeof(struct scatterlist);
1668         gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1669
1670         /*
1671          * TODO: test without low_dma, we should not need it since
1672          * the block layer will bounce the buffer for us
1673          *
1674          * XXX(hch): we shouldn't need GFP_DMA for the actual S/G list.
1675          */
1676         if (sfp->low_dma)
1677                  gfp_flags |= GFP_DMA;
1678         schp->buffer = kzalloc(sg_bufflen, gfp_flags);
1679         if (!schp->buffer)
1680                 return -ENOMEM;
1681         schp->sglist_len = sg_bufflen;
1682         return tablesize;       /* number of scat_gath elements allocated */
1683 }
1684
1685 #ifdef SG_ALLOW_DIO_CODE
1686 /* vvvvvvvv  following code borrowed from st driver's direct IO vvvvvvvvv */
1687         /* TODO: hopefully we can use the generic block layer code */
1688
1689 /* Pin down user pages and put them into a scatter gather list. Returns <= 0 if
1690    - mapping of all pages not successful
1691    (i.e., either completely successful or fails)
1692 */
1693 static int
1694 st_map_user_pages(struct scatterlist *sgl, const unsigned int max_pages,
1695                   unsigned long uaddr, size_t count, int rw)
1696 {
1697         unsigned long end = (uaddr + count + PAGE_SIZE - 1) >> PAGE_SHIFT;
1698         unsigned long start = uaddr >> PAGE_SHIFT;
1699         const int nr_pages = end - start;
1700         int res, i, j;
1701         struct page **pages;
1702
1703         /* User attempted Overflow! */
1704         if ((uaddr + count) < uaddr)
1705                 return -EINVAL;
1706
1707         /* Too big */
1708         if (nr_pages > max_pages)
1709                 return -ENOMEM;
1710
1711         /* Hmm? */
1712         if (count == 0)
1713                 return 0;
1714
1715         if ((pages = kmalloc(max_pages * sizeof(*pages), GFP_ATOMIC)) == NULL)
1716                 return -ENOMEM;
1717
1718         /* Try to fault in all of the necessary pages */
1719         down_read(&current->mm->mmap_sem);
1720         /* rw==READ means read from drive, write into memory area */
1721         res = get_user_pages(
1722                 current,
1723                 current->mm,
1724                 uaddr,
1725                 nr_pages,
1726                 rw == READ,
1727                 0, /* don't force */
1728                 pages,
1729                 NULL);
1730         up_read(&current->mm->mmap_sem);
1731
1732         /* Errors and no page mapped should return here */
1733         if (res < nr_pages)
1734                 goto out_unmap;
1735
1736         for (i=0; i < nr_pages; i++) {
1737                 /* FIXME: flush superflous for rw==READ,
1738                  * probably wrong function for rw==WRITE
1739                  */
1740                 flush_dcache_page(pages[i]);
1741                 /* ?? Is locking needed? I don't think so */
1742                 /* if (TestSetPageLocked(pages[i]))
1743                    goto out_unlock; */
1744         }
1745
1746         sgl[0].page = pages[0];
1747         sgl[0].offset = uaddr & ~PAGE_MASK;
1748         if (nr_pages > 1) {
1749                 sgl[0].length = PAGE_SIZE - sgl[0].offset;
1750                 count -= sgl[0].length;
1751                 for (i=1; i < nr_pages ; i++) {
1752                         sgl[i].page = pages[i];
1753                         sgl[i].length = count < PAGE_SIZE ? count : PAGE_SIZE;
1754                         count -= PAGE_SIZE;
1755                 }
1756         }
1757         else {
1758                 sgl[0].length = count;
1759         }
1760
1761         kfree(pages);
1762         return nr_pages;
1763
1764  out_unmap:
1765         if (res > 0) {
1766                 for (j=0; j < res; j++)
1767                         page_cache_release(pages[j]);
1768                 res = 0;
1769         }
1770         kfree(pages);
1771         return res;
1772 }
1773
1774
1775 /* And unmap them... */
1776 static int
1777 st_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_pages,
1778                     int dirtied)
1779 {
1780         int i;
1781
1782         for (i=0; i < nr_pages; i++) {
1783                 struct page *page = sgl[i].page;
1784
1785                 if (dirtied)
1786                         SetPageDirty(page);
1787                 /* unlock_page(page); */
1788                 /* FIXME: cache flush missing for rw==READ
1789                  * FIXME: call the correct reference counting function
1790                  */
1791                 page_cache_release(page);
1792         }
1793
1794         return 0;
1795 }
1796
1797 /* ^^^^^^^^  above code borrowed from st driver's direct IO ^^^^^^^^^ */
1798 #endif
1799
1800
1801 /* Returns: -ve -> error, 0 -> done, 1 -> try indirect */
1802 static int
1803 sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len)
1804 {
1805 #ifdef SG_ALLOW_DIO_CODE
1806         sg_io_hdr_t *hp = &srp->header;
1807         Sg_scatter_hold *schp = &srp->data;
1808         int sg_tablesize = sfp->parentdp->sg_tablesize;
1809         int mx_sc_elems, res;
1810         struct scsi_device *sdev = sfp->parentdp->device;
1811
1812         if (((unsigned long)hp->dxferp &
1813                         queue_dma_alignment(sdev->request_queue)) != 0)
1814                 return 1;
1815
1816         mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1817         if (mx_sc_elems <= 0) {
1818                 return 1;
1819         }
1820         res = st_map_user_pages(schp->buffer, mx_sc_elems,
1821                                 (unsigned long)hp->dxferp, dxfer_len,
1822                                 (SG_DXFER_TO_DEV == hp->dxfer_direction) ? 1 : 0);
1823         if (res <= 0) {
1824                 sg_remove_scat(schp);
1825                 return 1;
1826         }
1827         schp->k_use_sg = res;
1828         schp->dio_in_use = 1;
1829         hp->info |= SG_INFO_DIRECT_IO;
1830         return 0;
1831 #else
1832         return 1;
1833 #endif
1834 }
1835
1836 static int
1837 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1838 {
1839         struct scatterlist *sg;
1840         int ret_sz = 0, k, rem_sz, num, mx_sc_elems;
1841         int sg_tablesize = sfp->parentdp->sg_tablesize;
1842         int blk_size = buff_size;
1843         struct page *p = NULL;
1844
1845         if ((blk_size < 0) || (!sfp))
1846                 return -EFAULT;
1847         if (0 == blk_size)
1848                 ++blk_size;     /* don't know why */
1849 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1850         blk_size = (blk_size + SG_SECTOR_MSK) & (~SG_SECTOR_MSK);
1851         SCSI_LOG_TIMEOUT(4, printk("sg_build_indirect: buff_size=%d, blk_size=%d\n",
1852                                    buff_size, blk_size));
1853
1854         /* N.B. ret_sz carried into this block ... */
1855         mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1856         if (mx_sc_elems < 0)
1857                 return mx_sc_elems;     /* most likely -ENOMEM */
1858
1859         num = scatter_elem_sz;
1860         if (unlikely(num != scatter_elem_sz_prev)) {
1861                 if (num < PAGE_SIZE) {
1862                         scatter_elem_sz = PAGE_SIZE;
1863                         scatter_elem_sz_prev = PAGE_SIZE;
1864                 } else
1865                         scatter_elem_sz_prev = num;
1866         }
1867         for (k = 0, sg = schp->buffer, rem_sz = blk_size;
1868              (rem_sz > 0) && (k < mx_sc_elems);
1869              ++k, rem_sz -= ret_sz, ++sg) {
1870
1871                 num = (rem_sz > scatter_elem_sz_prev) ?
1872                       scatter_elem_sz_prev : rem_sz;
1873                 p = sg_page_malloc(num, sfp->low_dma, &ret_sz);
1874                 if (!p)
1875                         return -ENOMEM;
1876
1877                 if (num == scatter_elem_sz_prev) {
1878                         if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1879                                 scatter_elem_sz = ret_sz;
1880                                 scatter_elem_sz_prev = ret_sz;
1881                         }
1882                 }
1883                 sg->page = p;
1884                 sg->length = (ret_sz > num) ? num : ret_sz;
1885
1886                 SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k=%d, num=%d, "
1887                                  "ret_sz=%d\n", k, num, ret_sz));
1888         }               /* end of for loop */
1889
1890         schp->k_use_sg = k;
1891         SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, "
1892                          "rem_sz=%d\n", k, rem_sz));
1893
1894         schp->bufflen = blk_size;
1895         if (rem_sz > 0) /* must have failed */
1896                 return -ENOMEM;
1897
1898         return 0;
1899 }
1900
1901 static int
1902 sg_write_xfer(Sg_request * srp)
1903 {
1904         sg_io_hdr_t *hp = &srp->header;
1905         Sg_scatter_hold *schp = &srp->data;
1906         struct scatterlist *sg = schp->buffer;
1907         int num_xfer = 0;
1908         int j, k, onum, usglen, ksglen, res;
1909         int iovec_count = (int) hp->iovec_count;
1910         int dxfer_dir = hp->dxfer_direction;
1911         unsigned char *p;
1912         unsigned char __user *up;
1913         int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
1914
1915         if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_TO_DEV == dxfer_dir) ||
1916             (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
1917                 num_xfer = (int) (new_interface ? hp->dxfer_len : hp->flags);
1918                 if (schp->bufflen < num_xfer)
1919                         num_xfer = schp->bufflen;
1920         }
1921         if ((num_xfer <= 0) || (schp->dio_in_use) ||
1922             (new_interface
1923              && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
1924                 return 0;
1925
1926         SCSI_LOG_TIMEOUT(4, printk("sg_write_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
1927                           num_xfer, iovec_count, schp->k_use_sg));
1928         if (iovec_count) {
1929                 onum = iovec_count;
1930                 if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum))
1931                         return -EFAULT;
1932         } else
1933                 onum = 1;
1934
1935         ksglen = sg->length;
1936         p = page_address(sg->page);
1937         for (j = 0, k = 0; j < onum; ++j) {
1938                 res = sg_u_iovec(hp, iovec_count, j, 1, &usglen, &up);
1939                 if (res)
1940                         return res;
1941
1942                 for (; p; ++sg, ksglen = sg->length,
1943                      p = page_address(sg->page)) {
1944                         if (usglen <= 0)
1945                                 break;
1946                         if (ksglen > usglen) {
1947                                 if (usglen >= num_xfer) {
1948                                         if (__copy_from_user(p, up, num_xfer))
1949                                                 return -EFAULT;
1950                                         return 0;
1951                                 }
1952                                 if (__copy_from_user(p, up, usglen))
1953                                         return -EFAULT;
1954                                 p += usglen;
1955                                 ksglen -= usglen;
1956                                 break;
1957                         } else {
1958                                 if (ksglen >= num_xfer) {
1959                                         if (__copy_from_user(p, up, num_xfer))
1960                                                 return -EFAULT;
1961                                         return 0;
1962                                 }
1963                                 if (__copy_from_user(p, up, ksglen))
1964                                         return -EFAULT;
1965                                 up += ksglen;
1966                                 usglen -= ksglen;
1967                         }
1968                         ++k;
1969                         if (k >= schp->k_use_sg)
1970                                 return 0;
1971                 }
1972         }
1973
1974         return 0;
1975 }
1976
1977 static int
1978 sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
1979            int wr_xf, int *countp, unsigned char __user **up)
1980 {
1981         int num_xfer = (int) hp->dxfer_len;
1982         unsigned char __user *p = hp->dxferp;
1983         int count;
1984
1985         if (0 == sg_num) {
1986                 if (wr_xf && ('\0' == hp->interface_id))
1987                         count = (int) hp->flags;        /* holds "old" input_size */
1988                 else
1989                         count = num_xfer;
1990         } else {
1991                 sg_iovec_t iovec;
1992                 if (__copy_from_user(&iovec, p + ind*SZ_SG_IOVEC, SZ_SG_IOVEC))
1993                         return -EFAULT;
1994                 p = iovec.iov_base;
1995                 count = (int) iovec.iov_len;
1996         }
1997         if (!access_ok(wr_xf ? VERIFY_READ : VERIFY_WRITE, p, count))
1998                 return -EFAULT;
1999         if (up)
2000                 *up = p;
2001         if (countp)
2002                 *countp = count;
2003         return 0;
2004 }
2005
2006 static void
2007 sg_remove_scat(Sg_scatter_hold * schp)
2008 {
2009         SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
2010         if (schp->buffer && (schp->sglist_len > 0)) {
2011                 struct scatterlist *sg = schp->buffer;
2012
2013                 if (schp->dio_in_use) {
2014 #ifdef SG_ALLOW_DIO_CODE
2015                         st_unmap_user_pages(sg, schp->k_use_sg, TRUE);
2016 #endif
2017                 } else {
2018                         int k;
2019
2020                         for (k = 0; (k < schp->k_use_sg) && sg->page;
2021                              ++k, ++sg) {
2022                                 SCSI_LOG_TIMEOUT(5, printk(
2023                                     "sg_remove_scat: k=%d, pg=0x%p, len=%d\n",
2024                                     k, sg->page, sg->length));
2025                                 sg_page_free(sg->page, sg->length);
2026                         }
2027                 }
2028                 kfree(schp->buffer);
2029         }
2030         memset(schp, 0, sizeof (*schp));
2031 }
2032
2033 static int
2034 sg_read_xfer(Sg_request * srp)
2035 {
2036         sg_io_hdr_t *hp = &srp->header;
2037         Sg_scatter_hold *schp = &srp->data;
2038         struct scatterlist *sg = schp->buffer;
2039         int num_xfer = 0;
2040         int j, k, onum, usglen, ksglen, res;
2041         int iovec_count = (int) hp->iovec_count;
2042         int dxfer_dir = hp->dxfer_direction;
2043         unsigned char *p;
2044         unsigned char __user *up;
2045         int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
2046
2047         if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_FROM_DEV == dxfer_dir)
2048             || (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
2049                 num_xfer = hp->dxfer_len;
2050                 if (schp->bufflen < num_xfer)
2051                         num_xfer = schp->bufflen;
2052         }
2053         if ((num_xfer <= 0) || (schp->dio_in_use) ||
2054             (new_interface
2055              && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
2056                 return 0;
2057
2058         SCSI_LOG_TIMEOUT(4, printk("sg_read_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
2059                           num_xfer, iovec_count, schp->k_use_sg));
2060         if (iovec_count) {
2061                 onum = iovec_count;
2062                 if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum))
2063                         return -EFAULT;
2064         } else
2065                 onum = 1;
2066
2067         p = page_address(sg->page);
2068         ksglen = sg->length;
2069         for (j = 0, k = 0; j < onum; ++j) {
2070                 res = sg_u_iovec(hp, iovec_count, j, 0, &usglen, &up);
2071                 if (res)
2072                         return res;
2073
2074                 for (; p; ++sg, ksglen = sg->length,
2075                      p = page_address(sg->page)) {
2076                         if (usglen <= 0)
2077                                 break;
2078                         if (ksglen > usglen) {
2079                                 if (usglen >= num_xfer) {
2080                                         if (__copy_to_user(up, p, num_xfer))
2081                                                 return -EFAULT;
2082                                         return 0;
2083                                 }
2084                                 if (__copy_to_user(up, p, usglen))
2085                                         return -EFAULT;
2086                                 p += usglen;
2087                                 ksglen -= usglen;
2088                                 break;
2089                         } else {
2090                                 if (ksglen >= num_xfer) {
2091                                         if (__copy_to_user(up, p, num_xfer))
2092                                                 return -EFAULT;
2093                                         return 0;
2094                                 }
2095                                 if (__copy_to_user(up, p, ksglen))
2096                                         return -EFAULT;
2097                                 up += ksglen;
2098                                 usglen -= ksglen;
2099                         }
2100                         ++k;
2101                         if (k >= schp->k_use_sg)
2102                                 return 0;
2103                 }
2104         }
2105
2106         return 0;
2107 }
2108
2109 static int
2110 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
2111 {
2112         Sg_scatter_hold *schp = &srp->data;
2113         struct scatterlist *sg = schp->buffer;
2114         int k, num;
2115
2116         SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n",
2117                                    num_read_xfer));
2118         if ((!outp) || (num_read_xfer <= 0))
2119                 return 0;
2120
2121         for (k = 0; (k < schp->k_use_sg) && sg->page; ++k, ++sg) {
2122                 num = sg->length;
2123                 if (num > num_read_xfer) {
2124                         if (__copy_to_user(outp, page_address(sg->page),
2125                                            num_read_xfer))
2126                                 return -EFAULT;
2127                         break;
2128                 } else {
2129                         if (__copy_to_user(outp, page_address(sg->page),
2130                                            num))
2131                                 return -EFAULT;
2132                         num_read_xfer -= num;
2133                         if (num_read_xfer <= 0)
2134                                 break;
2135                         outp += num;
2136                 }
2137         }
2138
2139         return 0;
2140 }
2141
2142 static void
2143 sg_build_reserve(Sg_fd * sfp, int req_size)
2144 {
2145         Sg_scatter_hold *schp = &sfp->reserve;
2146
2147         SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
2148         do {
2149                 if (req_size < PAGE_SIZE)
2150                         req_size = PAGE_SIZE;
2151                 if (0 == sg_build_indirect(schp, sfp, req_size))
2152                         return;
2153                 else
2154                         sg_remove_scat(schp);
2155                 req_size >>= 1; /* divide by 2 */
2156         } while (req_size > (PAGE_SIZE / 2));
2157 }
2158
2159 static void
2160 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2161 {
2162         Sg_scatter_hold *req_schp = &srp->data;
2163         Sg_scatter_hold *rsv_schp = &sfp->reserve;
2164         struct scatterlist *sg = rsv_schp->buffer;
2165         int k, num, rem;
2166
2167         srp->res_used = 1;
2168         SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
2169         rem = size;
2170
2171         for (k = 0; k < rsv_schp->k_use_sg; ++k, ++sg) {
2172                 num = sg->length;
2173                 if (rem <= num) {
2174                         sfp->save_scat_len = num;
2175                         sg->length = rem;
2176                         req_schp->k_use_sg = k + 1;
2177                         req_schp->sglist_len = rsv_schp->sglist_len;
2178                         req_schp->buffer = rsv_schp->buffer;
2179
2180                         req_schp->bufflen = size;
2181                         req_schp->b_malloc_len = rsv_schp->b_malloc_len;
2182                         break;
2183                 } else
2184                         rem -= num;
2185         }
2186
2187         if (k >= rsv_schp->k_use_sg)
2188                 SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
2189 }
2190
2191 static void
2192 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2193 {
2194         Sg_scatter_hold *req_schp = &srp->data;
2195         Sg_scatter_hold *rsv_schp = &sfp->reserve;
2196
2197         SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->k_use_sg=%d\n",
2198                                    (int) req_schp->k_use_sg));
2199         if ((rsv_schp->k_use_sg > 0) && (req_schp->k_use_sg > 0)) {
2200                 struct scatterlist *sg = rsv_schp->buffer;
2201
2202                 if (sfp->save_scat_len > 0)
2203                         (sg + (req_schp->k_use_sg - 1))->length =
2204                             (unsigned) sfp->save_scat_len;
2205                 else
2206                         SCSI_LOG_TIMEOUT(1, printk ("sg_unlink_reserve: BAD save_scat_len\n"));
2207         }
2208         req_schp->k_use_sg = 0;
2209         req_schp->bufflen = 0;
2210         req_schp->buffer = NULL;
2211         req_schp->sglist_len = 0;
2212         sfp->save_scat_len = 0;
2213         srp->res_used = 0;
2214 }
2215
2216 static Sg_request *
2217 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2218 {
2219         Sg_request *resp;
2220         unsigned long iflags;
2221
2222         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2223         for (resp = sfp->headrp; resp; resp = resp->nextrp) {
2224                 /* look for requests that are ready + not SG_IO owned */
2225                 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2226                     ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2227                         resp->done = 2; /* guard against other readers */
2228                         break;
2229                 }
2230         }
2231         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2232         return resp;
2233 }
2234
2235 #ifdef CONFIG_SCSI_PROC_FS
2236 static Sg_request *
2237 sg_get_nth_request(Sg_fd * sfp, int nth)
2238 {
2239         Sg_request *resp;
2240         unsigned long iflags;
2241         int k;
2242
2243         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2244         for (k = 0, resp = sfp->headrp; resp && (k < nth);
2245              ++k, resp = resp->nextrp) ;
2246         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2247         return resp;
2248 }
2249 #endif
2250
2251 /* always adds to end of list */
2252 static Sg_request *
2253 sg_add_request(Sg_fd * sfp)
2254 {
2255         int k;
2256         unsigned long iflags;
2257         Sg_request *resp;
2258         Sg_request *rp = sfp->req_arr;
2259
2260         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2261         resp = sfp->headrp;
2262         if (!resp) {
2263                 memset(rp, 0, sizeof (Sg_request));
2264                 rp->parentfp = sfp;
2265                 resp = rp;
2266                 sfp->headrp = resp;
2267         } else {
2268                 if (0 == sfp->cmd_q)
2269                         resp = NULL;    /* command queuing disallowed */
2270                 else {
2271                         for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2272                                 if (!rp->parentfp)
2273                                         break;
2274                         }
2275                         if (k < SG_MAX_QUEUE) {
2276                                 memset(rp, 0, sizeof (Sg_request));
2277                                 rp->parentfp = sfp;
2278                                 while (resp->nextrp)
2279                                         resp = resp->nextrp;
2280                                 resp->nextrp = rp;
2281                                 resp = rp;
2282                         } else
2283                                 resp = NULL;
2284                 }
2285         }
2286         if (resp) {
2287                 resp->nextrp = NULL;
2288                 resp->header.duration = jiffies_to_msecs(jiffies);
2289         }
2290         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2291         return resp;
2292 }
2293
2294 /* Return of 1 for found; 0 for not found */
2295 static int
2296 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2297 {
2298         Sg_request *prev_rp;
2299         Sg_request *rp;
2300         unsigned long iflags;
2301         int res = 0;
2302
2303         if ((!sfp) || (!srp) || (!sfp->headrp))
2304                 return res;
2305         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2306         prev_rp = sfp->headrp;
2307         if (srp == prev_rp) {
2308                 sfp->headrp = prev_rp->nextrp;
2309                 prev_rp->parentfp = NULL;
2310                 res = 1;
2311         } else {
2312                 while ((rp = prev_rp->nextrp)) {
2313                         if (srp == rp) {
2314                                 prev_rp->nextrp = rp->nextrp;
2315                                 rp->parentfp = NULL;
2316                                 res = 1;
2317                                 break;
2318                         }
2319                         prev_rp = rp;
2320                 }
2321         }
2322         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2323         return res;
2324 }
2325
2326 #ifdef CONFIG_SCSI_PROC_FS
2327 static Sg_fd *
2328 sg_get_nth_sfp(Sg_device * sdp, int nth)
2329 {
2330         Sg_fd *resp;
2331         unsigned long iflags;
2332         int k;
2333
2334         read_lock_irqsave(&sg_dev_arr_lock, iflags);
2335         for (k = 0, resp = sdp->headfp; resp && (k < nth);
2336              ++k, resp = resp->nextfp) ;
2337         read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2338         return resp;
2339 }
2340 #endif
2341
2342 static Sg_fd *
2343 sg_add_sfp(Sg_device * sdp, int dev)
2344 {
2345         Sg_fd *sfp;
2346         unsigned long iflags;
2347         int bufflen;
2348
2349         sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2350         if (!sfp)
2351                 return NULL;
2352
2353         init_waitqueue_head(&sfp->read_wait);
2354         rwlock_init(&sfp->rq_list_lock);
2355
2356         sfp->timeout = SG_DEFAULT_TIMEOUT;
2357         sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2358         sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2359         sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
2360             sdp->device->host->unchecked_isa_dma : 1;
2361         sfp->cmd_q = SG_DEF_COMMAND_Q;
2362         sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2363         sfp->parentdp = sdp;
2364         write_lock_irqsave(&sg_dev_arr_lock, iflags);
2365         if (!sdp->headfp)
2366                 sdp->headfp = sfp;
2367         else {                  /* add to tail of existing list */
2368                 Sg_fd *pfp = sdp->headfp;
2369                 while (pfp->nextfp)
2370                         pfp = pfp->nextfp;
2371                 pfp->nextfp = sfp;
2372         }
2373         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2374         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));
2375         if (unlikely(sg_big_buff != def_reserved_size))
2376                 sg_big_buff = def_reserved_size;
2377
2378         bufflen = min_t(int, sg_big_buff,
2379                         sdp->device->request_queue->max_sectors * 512);
2380         sg_build_reserve(sfp, bufflen);
2381         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp:   bufflen=%d, k_use_sg=%d\n",
2382                            sfp->reserve.bufflen, sfp->reserve.k_use_sg));
2383         return sfp;
2384 }
2385
2386 static void
2387 __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2388 {
2389         Sg_fd *fp;
2390         Sg_fd *prev_fp;
2391
2392         prev_fp = sdp->headfp;
2393         if (sfp == prev_fp)
2394                 sdp->headfp = prev_fp->nextfp;
2395         else {
2396                 while ((fp = prev_fp->nextfp)) {
2397                         if (sfp == fp) {
2398                                 prev_fp->nextfp = fp->nextfp;
2399                                 break;
2400                         }
2401                         prev_fp = fp;
2402                 }
2403         }
2404         if (sfp->reserve.bufflen > 0) {
2405                 SCSI_LOG_TIMEOUT(6,
2406                         printk("__sg_remove_sfp:    bufflen=%d, k_use_sg=%d\n",
2407                         (int) sfp->reserve.bufflen, (int) sfp->reserve.k_use_sg));
2408                 sg_remove_scat(&sfp->reserve);
2409         }
2410         sfp->parentdp = NULL;
2411         SCSI_LOG_TIMEOUT(6, printk("__sg_remove_sfp:    sfp=0x%p\n", sfp));
2412         kfree(sfp);
2413 }
2414
2415 /* Returns 0 in normal case, 1 when detached and sdp object removed */
2416 static int
2417 sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2418 {
2419         Sg_request *srp;
2420         Sg_request *tsrp;
2421         int dirty = 0;
2422         int res = 0;
2423
2424         for (srp = sfp->headrp; srp; srp = tsrp) {
2425                 tsrp = srp->nextrp;
2426                 if (sg_srp_done(srp, sfp))
2427                         sg_finish_rem_req(srp);
2428                 else
2429                         ++dirty;
2430         }
2431         if (0 == dirty) {
2432                 unsigned long iflags;
2433
2434                 write_lock_irqsave(&sg_dev_arr_lock, iflags);
2435                 __sg_remove_sfp(sdp, sfp);
2436                 if (sdp->detached && (NULL == sdp->headfp)) {
2437                         int k, maxd;
2438
2439                         maxd = sg_dev_max;
2440                         for (k = 0; k < maxd; ++k) {
2441                                 if (sdp == sg_dev_arr[k])
2442                                         break;
2443                         }
2444                         if (k < maxd)
2445                                 sg_dev_arr[k] = NULL;
2446                         kfree((char *) sdp);
2447                         res = 1;
2448                 }
2449                 write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2450         } else {
2451                 /* MOD_INC's to inhibit unloading sg and associated adapter driver */
2452                 /* only bump the access_count if we actually succeeded in
2453                  * throwing another counter on the host module */
2454                 scsi_device_get(sdp->device);   /* XXX: retval ignored? */
2455                 sfp->closed = 1;        /* flag dirty state on this fd */
2456                 SCSI_LOG_TIMEOUT(1, printk("sg_remove_sfp: worrisome, %d writes pending\n",
2457                                   dirty));
2458         }
2459         return res;
2460 }
2461
2462 static int
2463 sg_res_in_use(Sg_fd * sfp)
2464 {
2465         const Sg_request *srp;
2466         unsigned long iflags;
2467
2468         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2469         for (srp = sfp->headrp; srp; srp = srp->nextrp)
2470                 if (srp->res_used)
2471                         break;
2472         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2473         return srp ? 1 : 0;
2474 }
2475
2476 /* The size fetched (value output via retSzp) set when non-NULL return */
2477 static struct page *
2478 sg_page_malloc(int rqSz, int lowDma, int *retSzp)
2479 {
2480         struct page *resp = NULL;
2481         gfp_t page_mask;
2482         int order, a_size;
2483         int resSz;
2484
2485         if ((rqSz <= 0) || (NULL == retSzp))
2486                 return resp;
2487
2488         if (lowDma)
2489                 page_mask = GFP_ATOMIC | GFP_DMA | __GFP_COMP | __GFP_NOWARN;
2490         else
2491                 page_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
2492
2493         for (order = 0, a_size = PAGE_SIZE; a_size < rqSz;
2494              order++, a_size <<= 1) ;
2495         resSz = a_size;         /* rounded up if necessary */
2496         resp = alloc_pages(page_mask, order);
2497         while ((!resp) && order) {
2498                 --order;
2499                 a_size >>= 1;   /* divide by 2, until PAGE_SIZE */
2500                 resp =  alloc_pages(page_mask, order);  /* try half */
2501                 resSz = a_size;
2502         }
2503         if (resp) {
2504                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2505                         memset(page_address(resp), 0, resSz);
2506                 *retSzp = resSz;
2507         }
2508         return resp;
2509 }
2510
2511 static void
2512 sg_page_free(struct page *page, int size)
2513 {
2514         int order, a_size;
2515
2516         if (!page)
2517                 return;
2518         for (order = 0, a_size = PAGE_SIZE; a_size < size;
2519              order++, a_size <<= 1) ;
2520         __free_pages(page, order);
2521 }
2522
2523 #ifndef MAINTENANCE_IN_CMD
2524 #define MAINTENANCE_IN_CMD 0xa3
2525 #endif
2526
2527 static unsigned char allow_ops[] = { TEST_UNIT_READY, REQUEST_SENSE,
2528         INQUIRY, READ_CAPACITY, READ_BUFFER, READ_6, READ_10, READ_12,
2529         READ_16, MODE_SENSE, MODE_SENSE_10, LOG_SENSE, REPORT_LUNS,
2530         SERVICE_ACTION_IN, RECEIVE_DIAGNOSTIC, READ_LONG, MAINTENANCE_IN_CMD
2531 };
2532
2533 static int
2534 sg_allow_access(unsigned char opcode, char dev_type)
2535 {
2536         int k;
2537
2538         if (TYPE_SCANNER == dev_type)   /* TYPE_ROM maybe burner */
2539                 return 1;
2540         for (k = 0; k < sizeof (allow_ops); ++k) {
2541                 if (opcode == allow_ops[k])
2542                         return 1;
2543         }
2544         return 0;
2545 }
2546
2547 #ifdef CONFIG_SCSI_PROC_FS
2548 static int
2549 sg_last_dev(void)
2550 {
2551         int k;
2552         unsigned long iflags;
2553
2554         read_lock_irqsave(&sg_dev_arr_lock, iflags);
2555         for (k = sg_dev_max - 1; k >= 0; --k)
2556                 if (sg_dev_arr[k] && sg_dev_arr[k]->device)
2557                         break;
2558         read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2559         return k + 1;           /* origin 1 */
2560 }
2561 #endif
2562
2563 static Sg_device *
2564 sg_get_dev(int dev)
2565 {
2566         Sg_device *sdp = NULL;
2567         unsigned long iflags;
2568
2569         if (sg_dev_arr && (dev >= 0)) {
2570                 read_lock_irqsave(&sg_dev_arr_lock, iflags);
2571                 if (dev < sg_dev_max)
2572                         sdp = sg_dev_arr[dev];
2573                 read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2574         }
2575         return sdp;
2576 }
2577
2578 #ifdef CONFIG_SCSI_PROC_FS
2579
2580 static struct proc_dir_entry *sg_proc_sgp = NULL;
2581
2582 static char sg_proc_sg_dirname[] = "scsi/sg";
2583
2584 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2585
2586 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2587 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2588                                   size_t count, loff_t *off);
2589 static struct file_operations adio_fops = {
2590         /* .owner, .read and .llseek added in sg_proc_init() */
2591         .open = sg_proc_single_open_adio,
2592         .write = sg_proc_write_adio,
2593         .release = single_release,
2594 };
2595
2596 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2597 static ssize_t sg_proc_write_dressz(struct file *filp,
2598                 const char __user *buffer, size_t count, loff_t *off);
2599 static struct file_operations dressz_fops = {
2600         .open = sg_proc_single_open_dressz,
2601         .write = sg_proc_write_dressz,
2602         .release = single_release,
2603 };
2604
2605 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2606 static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2607 static struct file_operations version_fops = {
2608         .open = sg_proc_single_open_version,
2609         .release = single_release,
2610 };
2611
2612 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2613 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2614 static struct file_operations devhdr_fops = {
2615         .open = sg_proc_single_open_devhdr,
2616         .release = single_release,
2617 };
2618
2619 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2620 static int sg_proc_open_dev(struct inode *inode, struct file *file);
2621 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2622 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2623 static void dev_seq_stop(struct seq_file *s, void *v);
2624 static struct file_operations dev_fops = {
2625         .open = sg_proc_open_dev,
2626         .release = seq_release,
2627 };
2628 static struct seq_operations dev_seq_ops = {
2629         .start = dev_seq_start,
2630         .next  = dev_seq_next,
2631         .stop  = dev_seq_stop,
2632         .show  = sg_proc_seq_show_dev,
2633 };
2634
2635 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2636 static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2637 static struct file_operations devstrs_fops = {
2638         .open = sg_proc_open_devstrs,
2639         .release = seq_release,
2640 };
2641 static struct seq_operations devstrs_seq_ops = {
2642         .start = dev_seq_start,
2643         .next  = dev_seq_next,
2644         .stop  = dev_seq_stop,
2645         .show  = sg_proc_seq_show_devstrs,
2646 };
2647
2648 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2649 static int sg_proc_open_debug(struct inode *inode, struct file *file);
2650 static struct file_operations debug_fops = {
2651         .open = sg_proc_open_debug,
2652         .release = seq_release,
2653 };
2654 static struct seq_operations debug_seq_ops = {
2655         .start = dev_seq_start,
2656         .next  = dev_seq_next,
2657         .stop  = dev_seq_stop,
2658         .show  = sg_proc_seq_show_debug,
2659 };
2660
2661
2662 struct sg_proc_leaf {
2663         const char * name;
2664         struct file_operations * fops;
2665 };
2666
2667 static struct sg_proc_leaf sg_proc_leaf_arr[] = {
2668         {"allow_dio", &adio_fops},
2669         {"debug", &debug_fops},
2670         {"def_reserved_size", &dressz_fops},
2671         {"device_hdr", &devhdr_fops},
2672         {"devices", &dev_fops},
2673         {"device_strs", &devstrs_fops},
2674         {"version", &version_fops}
2675 };
2676
2677 static int
2678 sg_proc_init(void)
2679 {
2680         int k, mask;
2681         int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2682         struct proc_dir_entry *pdep;
2683         struct sg_proc_leaf * leaf;
2684
2685         sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2686         if (!sg_proc_sgp)
2687                 return 1;
2688         for (k = 0; k < num_leaves; ++k) {
2689                 leaf = &sg_proc_leaf_arr[k];
2690                 mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2691                 pdep = create_proc_entry(leaf->name, mask, sg_proc_sgp);
2692                 if (pdep) {
2693                         leaf->fops->owner = THIS_MODULE,
2694                         leaf->fops->read = seq_read,
2695                         leaf->fops->llseek = seq_lseek,
2696                         pdep->proc_fops = leaf->fops;
2697                 }
2698         }
2699         return 0;
2700 }
2701
2702 static void
2703 sg_proc_cleanup(void)
2704 {
2705         int k;
2706         int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2707
2708         if (!sg_proc_sgp)
2709                 return;
2710         for (k = 0; k < num_leaves; ++k)
2711                 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2712         remove_proc_entry(sg_proc_sg_dirname, NULL);
2713 }
2714
2715
2716 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2717 {
2718         seq_printf(s, "%d\n", *((int *)s->private));
2719         return 0;
2720 }
2721
2722 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2723 {
2724         return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2725 }
2726
2727 static ssize_t
2728 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2729                    size_t count, loff_t *off)
2730 {
2731         int num;
2732         char buff[11];
2733
2734         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2735                 return -EACCES;
2736         num = (count < 10) ? count : 10;
2737         if (copy_from_user(buff, buffer, num))
2738                 return -EFAULT;
2739         buff[num] = '\0';
2740         sg_allow_dio = simple_strtoul(buff, NULL, 10) ? 1 : 0;
2741         return count;
2742 }
2743
2744 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2745 {
2746         return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2747 }
2748
2749 static ssize_t
2750 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2751                      size_t count, loff_t *off)
2752 {
2753         int num;
2754         unsigned long k = ULONG_MAX;
2755         char buff[11];
2756
2757         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2758                 return -EACCES;
2759         num = (count < 10) ? count : 10;
2760         if (copy_from_user(buff, buffer, num))
2761                 return -EFAULT;
2762         buff[num] = '\0';
2763         k = simple_strtoul(buff, NULL, 10);
2764         if (k <= 1048576) {     /* limit "big buff" to 1 MB */
2765                 sg_big_buff = k;
2766                 return count;
2767         }
2768         return -ERANGE;
2769 }
2770
2771 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2772 {
2773         seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2774                    sg_version_date);
2775         return 0;
2776 }
2777
2778 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2779 {
2780         return single_open(file, sg_proc_seq_show_version, NULL);
2781 }
2782
2783 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2784 {
2785         seq_printf(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\t"
2786                    "online\n");
2787         return 0;
2788 }
2789
2790 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2791 {
2792         return single_open(file, sg_proc_seq_show_devhdr, NULL);
2793 }
2794
2795 struct sg_proc_deviter {
2796         loff_t  index;
2797         size_t  max;
2798 };
2799
2800 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2801 {
2802         struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2803
2804         s->private = it;
2805         if (! it)
2806                 return NULL;
2807
2808         if (NULL == sg_dev_arr)
2809                 return NULL;
2810         it->index = *pos;
2811         it->max = sg_last_dev();
2812         if (it->index >= it->max)
2813                 return NULL;
2814         return it;
2815 }
2816
2817 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2818 {
2819         struct sg_proc_deviter * it = s->private;
2820
2821         *pos = ++it->index;
2822         return (it->index < it->max) ? it : NULL;
2823 }
2824
2825 static void dev_seq_stop(struct seq_file *s, void *v)
2826 {
2827         kfree(s->private);
2828 }
2829
2830 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2831 {
2832         return seq_open(file, &dev_seq_ops);
2833 }
2834
2835 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2836 {
2837         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2838         Sg_device *sdp;
2839         struct scsi_device *scsidp;
2840
2841         sdp = it ? sg_get_dev(it->index) : NULL;
2842         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2843                 seq_printf(s, "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n",
2844                               scsidp->host->host_no, scsidp->channel,
2845                               scsidp->id, scsidp->lun, (int) scsidp->type,
2846                               1,
2847                               (int) scsidp->queue_depth,
2848                               (int) scsidp->device_busy,
2849                               (int) scsi_device_online(scsidp));
2850         else
2851                 seq_printf(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2852         return 0;
2853 }
2854
2855 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2856 {
2857         return seq_open(file, &devstrs_seq_ops);
2858 }
2859
2860 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2861 {
2862         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2863         Sg_device *sdp;
2864         struct scsi_device *scsidp;
2865
2866         sdp = it ? sg_get_dev(it->index) : NULL;
2867         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2868                 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2869                            scsidp->vendor, scsidp->model, scsidp->rev);
2870         else
2871                 seq_printf(s, "<no active device>\n");
2872         return 0;
2873 }
2874
2875 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2876 {
2877         int k, m, new_interface, blen, usg;
2878         Sg_request *srp;
2879         Sg_fd *fp;
2880         const sg_io_hdr_t *hp;
2881         const char * cp;
2882         unsigned int ms;
2883
2884         for (k = 0; (fp = sg_get_nth_sfp(sdp, k)); ++k) {
2885                 seq_printf(s, "   FD(%d): timeout=%dms bufflen=%d "
2886                            "(res)sgat=%d low_dma=%d\n", k + 1,
2887                            jiffies_to_msecs(fp->timeout),
2888                            fp->reserve.bufflen,
2889                            (int) fp->reserve.k_use_sg,
2890                            (int) fp->low_dma);
2891                 seq_printf(s, "   cmd_q=%d f_packid=%d k_orphan=%d closed=%d\n",
2892                            (int) fp->cmd_q, (int) fp->force_packid,
2893                            (int) fp->keep_orphan, (int) fp->closed);
2894                 for (m = 0; (srp = sg_get_nth_request(fp, m)); ++m) {
2895                         hp = &srp->header;
2896                         new_interface = (hp->interface_id == '\0') ? 0 : 1;
2897                         if (srp->res_used) {
2898                                 if (new_interface &&
2899                                     (SG_FLAG_MMAP_IO & hp->flags))
2900                                         cp = "     mmap>> ";
2901                                 else
2902                                         cp = "     rb>> ";
2903                         } else {
2904                                 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2905                                         cp = "     dio>> ";
2906                                 else
2907                                         cp = "     ";
2908                         }
2909                         seq_printf(s, cp);
2910                         blen = srp->data.bufflen;
2911                         usg = srp->data.k_use_sg;
2912                         seq_printf(s, srp->done ?
2913                                    ((1 == srp->done) ?  "rcv:" : "fin:")
2914                                    : "act:");
2915                         seq_printf(s, " id=%d blen=%d",
2916                                    srp->header.pack_id, blen);
2917                         if (srp->done)
2918                                 seq_printf(s, " dur=%d", hp->duration);
2919                         else {
2920                                 ms = jiffies_to_msecs(jiffies);
2921                                 seq_printf(s, " t_o/elap=%d/%d",
2922                                         (new_interface ? hp->timeout :
2923                                                   jiffies_to_msecs(fp->timeout)),
2924                                         (ms > hp->duration ? ms - hp->duration : 0));
2925                         }
2926                         seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2927                                    (int) srp->data.cmd_opcode);
2928                 }
2929                 if (0 == m)
2930                         seq_printf(s, "     No requests active\n");
2931         }
2932 }
2933
2934 static int sg_proc_open_debug(struct inode *inode, struct file *file)
2935 {
2936         return seq_open(file, &debug_seq_ops);
2937 }
2938
2939 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2940 {
2941         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2942         Sg_device *sdp;
2943
2944         if (it && (0 == it->index)) {
2945                 seq_printf(s, "dev_max(currently)=%d max_active_device=%d "
2946                            "(origin 1)\n", sg_dev_max, (int)it->max);
2947                 seq_printf(s, " def_reserved_size=%d\n", sg_big_buff);
2948         }
2949         sdp = it ? sg_get_dev(it->index) : NULL;
2950         if (sdp) {
2951                 struct scsi_device *scsidp = sdp->device;
2952
2953                 if (NULL == scsidp) {
2954                         seq_printf(s, "device %d detached ??\n",
2955                                    (int)it->index);
2956                         return 0;
2957                 }
2958
2959                 if (sg_get_nth_sfp(sdp, 0)) {
2960                         seq_printf(s, " >>> device=%s ",
2961                                 sdp->disk->disk_name);
2962                         if (sdp->detached)
2963                                 seq_printf(s, "detached pending close ");
2964                         else
2965                                 seq_printf
2966                                     (s, "scsi%d chan=%d id=%d lun=%d   em=%d",
2967                                      scsidp->host->host_no,
2968                                      scsidp->channel, scsidp->id,
2969                                      scsidp->lun,
2970                                      scsidp->host->hostt->emulated);
2971                         seq_printf(s, " sg_tablesize=%d excl=%d\n",
2972                                    sdp->sg_tablesize, sdp->exclude);
2973                 }
2974                 sg_proc_debug_helper(s, sdp);
2975         }
2976         return 0;
2977 }
2978
2979 #endif                          /* CONFIG_SCSI_PROC_FS */
2980
2981 module_init(init_sg);
2982 module_exit(exit_sg);