git.oblomov.eu Git - linux-2.6/blob - drivers/scsi/sg.c

   1 /*
   2  *  History:
   3  *  Started: Aug 9 by Lawrence Foard (entropy@world.std.com),
   4  *           to allow user process control of SCSI devices.
   5  *  Development Sponsored by Killy Corp. NY NY
   6  *
   7  * Original driver (sg.c):
   8  *        Copyright (C) 1992 Lawrence Foard
   9  * Version 2 and 3 extensions to driver:
  10  *        Copyright (C) 1998 - 2005 Douglas Gilbert
  11  *
  12  *  Modified  19-JAN-1998  Richard Gooch <rgooch@atnf.csiro.au>  Devfs support
  13  *
  14  * This program is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2, or (at your option)
  17  * any later version.
  18  *
  19  */
  20
  21 static int sg_version_num = 30533;      /* 2 digits for each component */
  22 #define SG_VERSION_STR "3.5.33"
  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/config.h>
  32 #include <linux/module.h>
  33
  34 #include <linux/fs.h>
  35 #include <linux/kernel.h>
  36 #include <linux/sched.h>
  37 #include <linux/string.h>
  38 #include <linux/mm.h>
  39 #include <linux/errno.h>
  40 #include <linux/mtio.h>
  41 #include <linux/ioctl.h>
  42 #include <linux/fcntl.h>
  43 #include <linux/init.h>
  44 #include <linux/poll.h>
  45 #include <linux/smp_lock.h>
  46 #include <linux/moduleparam.h>
  47 #include <linux/devfs_fs_kernel.h>
  48 #include <linux/cdev.h>
  49 #include <linux/seq_file.h>
  50 #include <linux/blkdev.h>
  51 #include <linux/delay.h>
  52 #include <linux/scatterlist.h>
  53
  54 #include "scsi.h"
  55 #include <scsi/scsi_dbg.h>
  56 #include <scsi/scsi_host.h>
  57 #include <scsi/scsi_driver.h>
  58 #include <scsi/scsi_ioctl.h>
  59 #include <scsi/sg.h>
  60
  61 #include "scsi_logging.h"
  62
  63 #ifdef CONFIG_SCSI_PROC_FS
  64 #include <linux/proc_fs.h>
  65 static char *sg_version_date = "20050908";
  66
  67 static int sg_proc_init(void);
  68 static void sg_proc_cleanup(void);
  69 #endif
  70
  71 #define SG_ALLOW_DIO_DEF 0
  72 #define SG_ALLOW_DIO_CODE /* compile out by commenting this define */
  73
  74 #define SG_MAX_DEVS 32768
  75
  76 /*
  77  * Suppose you want to calculate the formula muldiv(x,m,d)=int(x * m / d)
  78  * Then when using 32 bit integers x * m may overflow during the calculation.
  79  * Replacing muldiv(x) by muldiv(x)=((x % d) * m) / d + int(x / d) * m
  80  * calculates the same, but prevents the overflow when both m and d
  81  * are "small" numbers (like HZ and USER_HZ).
  82  * Of course an overflow is inavoidable if the result of muldiv doesn't fit
  83  * in 32 bits.
  84  */
  85 #define MULDIV(X,MUL,DIV) ((((X % DIV) * MUL) / DIV) + ((X / DIV) * MUL))
  86
  87 #define SG_DEFAULT_TIMEOUT MULDIV(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
  88
  89 int sg_big_buff = SG_DEF_RESERVED_SIZE;
  90 /* N.B. This variable is readable and writeable via
  91    /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
  92    of this size (or less if there is not enough memory) will be reserved
  93    for use by this file descriptor. [Deprecated usage: this variable is also
  94    readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
  95    the kernel (i.e. it is not a module).] */
  96 static int def_reserved_size = -1;      /* picks up init parameter */
  97 static int sg_allow_dio = SG_ALLOW_DIO_DEF;
  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 Scsi_Request *dummy_cmdp;        /* only used for sizeof */
 108
 109 static DEFINE_RWLOCK(sg_dev_arr_lock);  /* Also used to lock
 110                                                            file descriptor list for device */
 111
 112 static struct class_interface sg_interface = {
 113         .add            = sg_add,
 114         .remove         = sg_remove,
 115 };
 116
 117 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
 118         unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
 119         unsigned short sglist_len; /* size of malloc'd scatter-gather list ++ */
 120         unsigned bufflen;       /* Size of (aggregate) data buffer */
 121         unsigned b_malloc_len;  /* actual len malloc'ed in buffer */
 122         void *buffer;           /* Data buffer or scatter list (k_use_sg>0) */
 123         char dio_in_use;        /* 0->indirect IO (or mmap), 1->dio */
 124         unsigned char cmd_opcode; /* first byte of command */
 125 } Sg_scatter_hold;
 126
 127 struct sg_device;               /* forward declarations */
 128 struct sg_fd;
 129
 130 typedef struct sg_request {     /* SG_MAX_QUEUE requests outstanding per file */
 131         Scsi_Request *my_cmdp;  /* != 0  when request with lower levels */
 132         struct sg_request *nextrp;      /* NULL -> tail request (slist) */
 133         struct sg_fd *parentfp; /* NULL -> not in use */
 134         Sg_scatter_hold data;   /* hold buffer, perhaps scatter list */
 135         sg_io_hdr_t header;     /* scsi command+info, see <scsi/sg.h> */
 136         unsigned char sense_b[sizeof (dummy_cmdp->sr_sense_buffer)];
 137         char res_used;          /* 1 -> using reserve buffer, 0 -> not ... */
 138         char orphan;            /* 1 -> drop on sight, 0 -> normal */
 139         char sg_io_owned;       /* 1 -> packet belongs to SG_IO */
 140         volatile char done;     /* 0->before bh, 1->before read, 2->read */
 141 } Sg_request;
 142
 143 typedef struct sg_fd {          /* holds the state of a file descriptor */
 144         struct sg_fd *nextfp;   /* NULL when last opened fd on this device */
 145         struct sg_device *parentdp;     /* owning device */
 146         wait_queue_head_t read_wait;    /* queue read until command done */
 147         rwlock_t rq_list_lock;  /* protect access to list in req_arr */
 148         int timeout;            /* defaults to SG_DEFAULT_TIMEOUT      */
 149         int timeout_user;       /* defaults to SG_DEFAULT_TIMEOUT_USER */
 150         Sg_scatter_hold reserve;        /* buffer held for this file descriptor */
 151         unsigned save_scat_len; /* original length of trunc. scat. element */
 152         Sg_request *headrp;     /* head of request slist, NULL->empty */
 153         struct fasync_struct *async_qp; /* used by asynchronous notification */
 154         Sg_request req_arr[SG_MAX_QUEUE];       /* used as singly-linked list */
 155         char low_dma;           /* as in parent but possibly overridden to 1 */
 156         char force_packid;      /* 1 -> pack_id input to read(), 0 -> ignored */
 157         volatile char closed;   /* 1 -> fd closed but request(s) outstanding */
 158         char cmd_q;             /* 1 -> allow command queuing, 0 -> don't */
 159         char next_cmd_len;      /* 0 -> automatic (def), >0 -> use on next write() */
 160         char keep_orphan;       /* 0 -> drop orphan (def), 1 -> keep for read() */
 161         char mmap_called;       /* 0 -> mmap() never called on this fd */
 162 } Sg_fd;
 163
 164 typedef struct sg_device { /* holds the state of each scsi generic device */
 165         struct scsi_device *device;
 166         wait_queue_head_t o_excl_wait;  /* queue open() when O_EXCL in use */
 167         int sg_tablesize;       /* adapter's max scatter-gather table size */
 168         Sg_fd *headfp;          /* first open fd belonging to this device */
 169         volatile char detached; /* 0->attached, 1->detached pending removal */
 170         volatile char exclude;  /* opened for exclusive access */
 171         char sgdebug;           /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
 172         struct gendisk *disk;
 173         struct cdev * cdev;     /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
 174 } Sg_device;
 175
 176 static int sg_fasync(int fd, struct file *filp, int mode);
 177 static void sg_cmd_done(Scsi_Cmnd * SCpnt);     /* tasklet or soft irq callback */
 178 static int sg_start_req(Sg_request * srp);
 179 static void sg_finish_rem_req(Sg_request * srp);
 180 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
 181 static int sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp,
 182                          int tablesize);
 183 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
 184                            Sg_request * srp);
 185 static ssize_t sg_new_write(Sg_fd * sfp, const char __user *buf, size_t count,
 186                             int blocking, int read_only, Sg_request ** o_srp);
 187 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
 188                            unsigned char *cmnd, int timeout, int blocking);
 189 static int sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
 190                       int wr_xf, int *countp, unsigned char __user **up);
 191 static int sg_write_xfer(Sg_request * srp);
 192 static int sg_read_xfer(Sg_request * srp);
 193 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
 194 static void sg_remove_scat(Sg_scatter_hold * schp);
 195 static void sg_build_reserve(Sg_fd * sfp, int req_size);
 196 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
 197 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
 198 static char *sg_page_malloc(int rqSz, int lowDma, int *retSzp);
 199 static void sg_page_free(char *buff, int size);
 200 static Sg_fd *sg_add_sfp(Sg_device * sdp, int dev);
 201 static int sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
 202 static void __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
 203 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
 204 static Sg_request *sg_add_request(Sg_fd * sfp);
 205 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
 206 static int sg_res_in_use(Sg_fd * sfp);
 207 static int sg_allow_access(unsigned char opcode, char dev_type);
 208 static int sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len);
 209 static Sg_device *sg_get_dev(int dev);
 210 static inline unsigned char *sg_scatg2virt(const struct scatterlist *sclp);
 211 #ifdef CONFIG_SCSI_PROC_FS
 212 static int sg_last_dev(void);
 213 #endif
 214
 215 static Sg_device **sg_dev_arr = NULL;
 216 static int sg_dev_max;
 217 static int sg_nr_dev;
 218
 219 #define SZ_SG_HEADER sizeof(struct sg_header)
 220 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
 221 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
 222 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
 223
 224 static int
 225 sg_open(struct inode *inode, struct file *filp)
 226 {
 227         int dev = iminor(inode);
 228         int flags = filp->f_flags;
 229         Sg_device *sdp;
 230         Sg_fd *sfp;
 231         int res;
 232         int retval;
 233
 234         nonseekable_open(inode, filp);
 235         SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags));
 236         sdp = sg_get_dev(dev);
 237         if ((!sdp) || (!sdp->device))
 238                 return -ENXIO;
 239         if (sdp->detached)
 240                 return -ENODEV;
 241
 242         /* This driver's module count bumped by fops_get in <linux/fs.h> */
 243         /* Prevent the device driver from vanishing while we sleep */
 244         retval = scsi_device_get(sdp->device);
 245         if (retval)
 246                 return retval;
 247
 248         if (!((flags & O_NONBLOCK) ||
 249               scsi_block_when_processing_errors(sdp->device))) {
 250                 retval = -ENXIO;
 251                 /* we are in error recovery for this device */
 252                 goto error_out;
 253         }
 254
 255         if (flags & O_EXCL) {
 256                 if (O_RDONLY == (flags & O_ACCMODE)) {
 257                         retval = -EPERM; /* Can't lock it with read only access */
 258                         goto error_out;
 259                 }
 260                 if (sdp->headfp && (flags & O_NONBLOCK)) {
 261                         retval = -EBUSY;
 262                         goto error_out;
 263                 }
 264                 res = 0;
 265                 __wait_event_interruptible(sdp->o_excl_wait,
 266                         ((sdp->headfp || sdp->exclude) ? 0 : (sdp->exclude = 1)), res);
 267                 if (res) {
 268                         retval = res;   /* -ERESTARTSYS because signal hit process */
 269                         goto error_out;
 270                 }
 271         } else if (sdp->exclude) {      /* some other fd has an exclusive lock on dev */
 272                 if (flags & O_NONBLOCK) {
 273                         retval = -EBUSY;
 274                         goto error_out;
 275                 }
 276                 res = 0;
 277                 __wait_event_interruptible(sdp->o_excl_wait, (!sdp->exclude),
 278                                            res);
 279                 if (res) {
 280                         retval = res;   /* -ERESTARTSYS because signal hit process */
 281                         goto error_out;
 282                 }
 283         }
 284         if (sdp->detached) {
 285                 retval = -ENODEV;
 286                 goto error_out;
 287         }
 288         if (!sdp->headfp) {     /* no existing opens on this device */
 289                 sdp->sgdebug = 0;
 290                 sdp->sg_tablesize = sdp->device->host->sg_tablesize;
 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         if (!access_ok(VERIFY_WRITE, buf, count))
 344                 return -EFAULT;
 345         if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
 346                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 347                 if (!old_hdr)
 348                         return -ENOMEM;
 349                 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
 350                         retval = -EFAULT;
 351                         goto free_old_hdr;
 352                 }
 353                 if (old_hdr->reply_len < 0) {
 354                         if (count >= SZ_SG_IO_HDR) {
 355                                 sg_io_hdr_t *new_hdr;
 356                                 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
 357                                 if (!new_hdr) {
 358                                         retval = -ENOMEM;
 359                                         goto free_old_hdr;
 360                                 }
 361                                 retval =__copy_from_user
 362                                     (new_hdr, buf, SZ_SG_IO_HDR);
 363                                 req_pack_id = new_hdr->pack_id;
 364                                 kfree(new_hdr);
 365                                 if (retval) {
 366                                         retval = -EFAULT;
 367                                         goto free_old_hdr;
 368                                 }
 369                         }
 370                 } else
 371                         req_pack_id = old_hdr->pack_id;
 372         }
 373         srp = sg_get_rq_mark(sfp, req_pack_id);
 374         if (!srp) {             /* now wait on packet to arrive */
 375                 if (sdp->detached) {
 376                         retval = -ENODEV;
 377                         goto free_old_hdr;
 378                 }
 379                 if (filp->f_flags & O_NONBLOCK) {
 380                         retval = -EAGAIN;
 381                         goto free_old_hdr;
 382                 }
 383                 while (1) {
 384                         retval = 0; /* following macro beats race condition */
 385                         __wait_event_interruptible(sfp->read_wait,
 386                                 (sdp->detached ||
 387                                 (srp = sg_get_rq_mark(sfp, req_pack_id))),
 388                                 retval);
 389                         if (sdp->detached) {
 390                                 retval = -ENODEV;
 391                                 goto free_old_hdr;
 392                         }
 393                         if (0 == retval)
 394                                 break;
 395
 396                         /* -ERESTARTSYS as signal hit process */
 397                         goto free_old_hdr;
 398                 }
 399         }
 400         if (srp->header.interface_id != '\0') {
 401                 retval = sg_new_read(sfp, buf, count, srp);
 402                 goto free_old_hdr;
 403         }
 404
 405         hp = &srp->header;
 406         if (old_hdr == NULL) {
 407                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 408                 if (! old_hdr) {
 409                         retval = -ENOMEM;
 410                         goto free_old_hdr;
 411                 }
 412         }
 413         memset(old_hdr, 0, SZ_SG_HEADER);
 414         old_hdr->reply_len = (int) hp->timeout;
 415         old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
 416         old_hdr->pack_id = hp->pack_id;
 417         old_hdr->twelve_byte =
 418             ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
 419         old_hdr->target_status = hp->masked_status;
 420         old_hdr->host_status = hp->host_status;
 421         old_hdr->driver_status = hp->driver_status;
 422         if ((CHECK_CONDITION & hp->masked_status) ||
 423             (DRIVER_SENSE & hp->driver_status))
 424                 memcpy(old_hdr->sense_buffer, srp->sense_b,
 425                        sizeof (old_hdr->sense_buffer));
 426         switch (hp->host_status) {
 427         /* This setup of 'result' is for backward compatibility and is best
 428            ignored by the user who should use target, host + driver status */
 429         case DID_OK:
 430         case DID_PASSTHROUGH:
 431         case DID_SOFT_ERROR:
 432                 old_hdr->result = 0;
 433                 break;
 434         case DID_NO_CONNECT:
 435         case DID_BUS_BUSY:
 436         case DID_TIME_OUT:
 437                 old_hdr->result = EBUSY;
 438                 break;
 439         case DID_BAD_TARGET:
 440         case DID_ABORT:
 441         case DID_PARITY:
 442         case DID_RESET:
 443         case DID_BAD_INTR:
 444                 old_hdr->result = EIO;
 445                 break;
 446         case DID_ERROR:
 447                 old_hdr->result = (srp->sense_b[0] == 0 &&
 448                                   hp->masked_status == GOOD) ? 0 : EIO;
 449                 break;
 450         default:
 451                 old_hdr->result = EIO;
 452                 break;
 453         }
 454
 455         /* Now copy the result back to the user buffer.  */
 456         if (count >= SZ_SG_HEADER) {
 457                 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
 458                         retval = -EFAULT;
 459                         goto free_old_hdr;
 460                 }
 461                 buf += SZ_SG_HEADER;
 462                 if (count > old_hdr->reply_len)
 463                         count = old_hdr->reply_len;
 464                 if (count > SZ_SG_HEADER) {
 465                         if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
 466                                 retval = -EFAULT;
 467                                 goto free_old_hdr;
 468                         }
 469                 }
 470         } else
 471                 count = (old_hdr->result == 0) ? 0 : -EIO;
 472         sg_finish_rem_req(srp);
 473         retval = count;
 474 free_old_hdr:
 475         kfree(old_hdr);
 476         return retval;
 477 }
 478
 479 static ssize_t
 480 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
 481 {
 482         sg_io_hdr_t *hp = &srp->header;
 483         int err = 0;
 484         int len;
 485
 486         if (count < SZ_SG_IO_HDR) {
 487                 err = -EINVAL;
 488                 goto err_out;
 489         }
 490         hp->sb_len_wr = 0;
 491         if ((hp->mx_sb_len > 0) && hp->sbp) {
 492                 if ((CHECK_CONDITION & hp->masked_status) ||
 493                     (DRIVER_SENSE & hp->driver_status)) {
 494                         int sb_len = sizeof (dummy_cmdp->sr_sense_buffer);
 495                         sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
 496                         len = 8 + (int) srp->sense_b[7];        /* Additional sense length field */
 497                         len = (len > sb_len) ? sb_len : len;
 498                         if (copy_to_user(hp->sbp, srp->sense_b, len)) {
 499                                 err = -EFAULT;
 500                                 goto err_out;
 501                         }
 502                         hp->sb_len_wr = len;
 503                 }
 504         }
 505         if (hp->masked_status || hp->host_status || hp->driver_status)
 506                 hp->info |= SG_INFO_CHECK;
 507         if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
 508                 err = -EFAULT;
 509                 goto err_out;
 510         }
 511         err = sg_read_xfer(srp);
 512       err_out:
 513         sg_finish_rem_req(srp);
 514         return (0 == err) ? count : err;
 515 }
 516
 517 static ssize_t
 518 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
 519 {
 520         int mxsize, cmd_size, k;
 521         int input_size, blocking;
 522         unsigned char opcode;
 523         Sg_device *sdp;
 524         Sg_fd *sfp;
 525         Sg_request *srp;
 526         struct sg_header old_hdr;
 527         sg_io_hdr_t *hp;
 528         unsigned char cmnd[sizeof (dummy_cmdp->sr_cmnd)];
 529
 530         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 531                 return -ENXIO;
 532         SCSI_LOG_TIMEOUT(3, printk("sg_write: %s, count=%d\n",
 533                                    sdp->disk->disk_name, (int) count));
 534         if (sdp->detached)
 535                 return -ENODEV;
 536         if (!((filp->f_flags & O_NONBLOCK) ||
 537               scsi_block_when_processing_errors(sdp->device)))
 538                 return -ENXIO;
 539
 540         if (!access_ok(VERIFY_READ, buf, count))
 541                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 542         if (count < SZ_SG_HEADER)
 543                 return -EIO;
 544         if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
 545                 return -EFAULT;
 546         blocking = !(filp->f_flags & O_NONBLOCK);
 547         if (old_hdr.reply_len < 0)
 548                 return sg_new_write(sfp, buf, count, blocking, 0, NULL);
 549         if (count < (SZ_SG_HEADER + 6))
 550                 return -EIO;    /* The minimum scsi command length is 6 bytes. */
 551
 552         if (!(srp = sg_add_request(sfp))) {
 553                 SCSI_LOG_TIMEOUT(1, printk("sg_write: queue full\n"));
 554                 return -EDOM;
 555         }
 556         buf += SZ_SG_HEADER;
 557         __get_user(opcode, buf);
 558         if (sfp->next_cmd_len > 0) {
 559                 if (sfp->next_cmd_len > MAX_COMMAND_SIZE) {
 560                         SCSI_LOG_TIMEOUT(1, printk("sg_write: command length too long\n"));
 561                         sfp->next_cmd_len = 0;
 562                         sg_remove_request(sfp, srp);
 563                         return -EIO;
 564                 }
 565                 cmd_size = sfp->next_cmd_len;
 566                 sfp->next_cmd_len = 0;  /* reset so only this write() effected */
 567         } else {
 568                 cmd_size = COMMAND_SIZE(opcode);        /* based on SCSI command group */
 569                 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
 570                         cmd_size = 12;
 571         }
 572         SCSI_LOG_TIMEOUT(4, printk(
 573                 "sg_write:   scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
 574 /* Determine buffer size.  */
 575         input_size = count - cmd_size;
 576         mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
 577         mxsize -= SZ_SG_HEADER;
 578         input_size -= SZ_SG_HEADER;
 579         if (input_size < 0) {
 580                 sg_remove_request(sfp, srp);
 581                 return -EIO;    /* User did not pass enough bytes for this command. */
 582         }
 583         hp = &srp->header;
 584         hp->interface_id = '\0';        /* indicator of old interface tunnelled */
 585         hp->cmd_len = (unsigned char) cmd_size;
 586         hp->iovec_count = 0;
 587         hp->mx_sb_len = 0;
 588         if (input_size > 0)
 589                 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
 590                     SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
 591         else
 592                 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
 593         hp->dxfer_len = mxsize;
 594         hp->dxferp = (char __user *)buf + cmd_size;
 595         hp->sbp = NULL;
 596         hp->timeout = old_hdr.reply_len;        /* structure abuse ... */
 597         hp->flags = input_size; /* structure abuse ... */
 598         hp->pack_id = old_hdr.pack_id;
 599         hp->usr_ptr = NULL;
 600         if (__copy_from_user(cmnd, buf, cmd_size))
 601                 return -EFAULT;
 602         /*
 603          * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
 604          * but is is possible that the app intended SG_DXFER_TO_DEV, because there
 605          * is a non-zero input_size, so emit a warning.
 606          */
 607         if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV)
 608                 if (printk_ratelimit())
 609                         printk(KERN_WARNING
 610                                "sg_write: data in/out %d/%d bytes for SCSI command 0x%x--"
 611                                "guessing data in;\n" KERN_WARNING "   "
 612                                "program %s not setting count and/or reply_len properly\n",
 613                                old_hdr.reply_len - (int)SZ_SG_HEADER,
 614                                input_size, (unsigned int) cmnd[0],
 615                                current->comm);
 616         k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
 617         return (k < 0) ? k : count;
 618 }
 619
 620 static ssize_t
 621 sg_new_write(Sg_fd * sfp, const char __user *buf, size_t count,
 622              int blocking, int read_only, Sg_request ** o_srp)
 623 {
 624         int k;
 625         Sg_request *srp;
 626         sg_io_hdr_t *hp;
 627         unsigned char cmnd[sizeof (dummy_cmdp->sr_cmnd)];
 628         int timeout;
 629         unsigned long ul_timeout;
 630
 631         if (count < SZ_SG_IO_HDR)
 632                 return -EINVAL;
 633         if (!access_ok(VERIFY_READ, buf, count))
 634                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 635
 636         sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
 637         if (!(srp = sg_add_request(sfp))) {
 638                 SCSI_LOG_TIMEOUT(1, printk("sg_new_write: queue full\n"));
 639                 return -EDOM;
 640         }
 641         hp = &srp->header;
 642         if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
 643                 sg_remove_request(sfp, srp);
 644                 return -EFAULT;
 645         }
 646         if (hp->interface_id != 'S') {
 647                 sg_remove_request(sfp, srp);
 648                 return -ENOSYS;
 649         }
 650         if (hp->flags & SG_FLAG_MMAP_IO) {
 651                 if (hp->dxfer_len > sfp->reserve.bufflen) {
 652                         sg_remove_request(sfp, srp);
 653                         return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
 654                 }
 655                 if (hp->flags & SG_FLAG_DIRECT_IO) {
 656                         sg_remove_request(sfp, srp);
 657                         return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
 658                 }
 659                 if (sg_res_in_use(sfp)) {
 660                         sg_remove_request(sfp, srp);
 661                         return -EBUSY;  /* reserve buffer already being used */
 662                 }
 663         }
 664         ul_timeout = msecs_to_jiffies(srp->header.timeout);
 665         timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
 666         if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
 667                 sg_remove_request(sfp, srp);
 668                 return -EMSGSIZE;
 669         }
 670         if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
 671                 sg_remove_request(sfp, srp);
 672                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 673         }
 674         if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
 675                 sg_remove_request(sfp, srp);
 676                 return -EFAULT;
 677         }
 678         if (read_only &&
 679             (!sg_allow_access(cmnd[0], sfp->parentdp->device->type))) {
 680                 sg_remove_request(sfp, srp);
 681                 return -EPERM;
 682         }
 683         k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
 684         if (k < 0)
 685                 return k;
 686         if (o_srp)
 687                 *o_srp = srp;
 688         return count;
 689 }
 690
 691 static int
 692 sg_common_write(Sg_fd * sfp, Sg_request * srp,
 693                 unsigned char *cmnd, int timeout, int blocking)
 694 {
 695         int k;
 696         Scsi_Request *SRpnt;
 697         Sg_device *sdp = sfp->parentdp;
 698         sg_io_hdr_t *hp = &srp->header;
 699         request_queue_t *q;
 700
 701         srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
 702         hp->status = 0;
 703         hp->masked_status = 0;
 704         hp->msg_status = 0;
 705         hp->info = 0;
 706         hp->host_status = 0;
 707         hp->driver_status = 0;
 708         hp->resid = 0;
 709         SCSI_LOG_TIMEOUT(4, printk("sg_common_write:  scsi opcode=0x%02x, cmd_size=%d\n",
 710                           (int) cmnd[0], (int) hp->cmd_len));
 711
 712         if ((k = sg_start_req(srp))) {
 713                 SCSI_LOG_TIMEOUT(1, printk("sg_write: start_req err=%d\n", k));
 714                 sg_finish_rem_req(srp);
 715                 return k;       /* probably out of space --> ENOMEM */
 716         }
 717         if ((k = sg_write_xfer(srp))) {
 718                 SCSI_LOG_TIMEOUT(1, printk("sg_write: write_xfer, bad address\n"));
 719                 sg_finish_rem_req(srp);
 720                 return k;
 721         }
 722         if (sdp->detached) {
 723                 sg_finish_rem_req(srp);
 724                 return -ENODEV;
 725         }
 726         SRpnt = scsi_allocate_request(sdp->device, GFP_ATOMIC);
 727         if (SRpnt == NULL) {
 728                 SCSI_LOG_TIMEOUT(1, printk("sg_write: no mem\n"));
 729                 sg_finish_rem_req(srp);
 730                 return -ENOMEM;
 731         }
 732
 733         srp->my_cmdp = SRpnt;
 734         q = SRpnt->sr_device->request_queue;
 735         SRpnt->sr_request->rq_disk = sdp->disk;
 736         SRpnt->sr_sense_buffer[0] = 0;
 737         SRpnt->sr_cmd_len = hp->cmd_len;
 738         SRpnt->sr_use_sg = srp->data.k_use_sg;
 739         SRpnt->sr_sglist_len = srp->data.sglist_len;
 740         SRpnt->sr_bufflen = srp->data.bufflen;
 741         SRpnt->sr_underflow = 0;
 742         SRpnt->sr_buffer = srp->data.buffer;
 743         switch (hp->dxfer_direction) {
 744         case SG_DXFER_TO_FROM_DEV:
 745         case SG_DXFER_FROM_DEV:
 746                 SRpnt->sr_data_direction = DMA_FROM_DEVICE;
 747                 break;
 748         case SG_DXFER_TO_DEV:
 749                 SRpnt->sr_data_direction = DMA_TO_DEVICE;
 750                 break;
 751         case SG_DXFER_UNKNOWN:
 752                 SRpnt->sr_data_direction = DMA_BIDIRECTIONAL;
 753                 break;
 754         default:
 755                 SRpnt->sr_data_direction = DMA_NONE;
 756                 break;
 757         }
 758         SRpnt->upper_private_data = srp;
 759         srp->data.k_use_sg = 0;
 760         srp->data.sglist_len = 0;
 761         srp->data.bufflen = 0;
 762         srp->data.buffer = NULL;
 763         hp->duration = jiffies_to_msecs(jiffies);
 764 /* Now send everything of to mid-level. The next time we hear about this
 765    packet is when sg_cmd_done() is called (i.e. a callback). */
 766         scsi_do_req(SRpnt, (void *) cmnd,
 767                     (void *) SRpnt->sr_buffer, hp->dxfer_len,
 768                     sg_cmd_done, timeout, SG_DEFAULT_RETRIES);
 769         /* dxfer_len overwrites SRpnt->sr_bufflen, hence need for b_malloc_len */
 770         return 0;
 771 }
 772
 773 static int
 774 sg_srp_done(Sg_request *srp, Sg_fd *sfp)
 775 {
 776         unsigned long iflags;
 777         int done;
 778
 779         read_lock_irqsave(&sfp->rq_list_lock, iflags);
 780         done = srp->done;
 781         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 782         return done;
 783 }
 784
 785 static int
 786 sg_ioctl(struct inode *inode, struct file *filp,
 787          unsigned int cmd_in, unsigned long arg)
 788 {
 789         void __user *p = (void __user *)arg;
 790         int __user *ip = p;
 791         int result, val, read_only;
 792         Sg_device *sdp;
 793         Sg_fd *sfp;
 794         Sg_request *srp;
 795         unsigned long iflags;
 796
 797         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 798                 return -ENXIO;
 799         SCSI_LOG_TIMEOUT(3, printk("sg_ioctl: %s, cmd=0x%x\n",
 800                                    sdp->disk->disk_name, (int) cmd_in));
 801         read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
 802
 803         switch (cmd_in) {
 804         case SG_IO:
 805                 {
 806                         int blocking = 1;       /* ignore O_NONBLOCK flag */
 807
 808                         if (sdp->detached)
 809                                 return -ENODEV;
 810                         if (!scsi_block_when_processing_errors(sdp->device))
 811                                 return -ENXIO;
 812                         if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
 813                                 return -EFAULT;
 814                         result =
 815                             sg_new_write(sfp, p, SZ_SG_IO_HDR,
 816                                          blocking, read_only, &srp);
 817                         if (result < 0)
 818                                 return result;
 819                         srp->sg_io_owned = 1;
 820                         while (1) {
 821                                 result = 0;     /* following macro to beat race condition */
 822                                 __wait_event_interruptible(sfp->read_wait,
 823                                         (sdp->detached || sfp->closed || sg_srp_done(srp, sfp)),
 824                                                            result);
 825                                 if (sdp->detached)
 826                                         return -ENODEV;
 827                                 if (sfp->closed)
 828                                         return 0;       /* request packet dropped already */
 829                                 if (0 == result)
 830                                         break;
 831                                 srp->orphan = 1;
 832                                 return result;  /* -ERESTARTSYS because signal hit process */
 833                         }
 834                         write_lock_irqsave(&sfp->rq_list_lock, iflags);
 835                         srp->done = 2;
 836                         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 837                         result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
 838                         return (result < 0) ? result : 0;
 839                 }
 840         case SG_SET_TIMEOUT:
 841                 result = get_user(val, ip);
 842                 if (result)
 843                         return result;
 844                 if (val < 0)
 845                         return -EIO;
 846                 if (val >= MULDIV (INT_MAX, USER_HZ, HZ))
 847                     val = MULDIV (INT_MAX, USER_HZ, HZ);
 848                 sfp->timeout_user = val;
 849                 sfp->timeout = MULDIV (val, HZ, USER_HZ);
 850
 851                 return 0;
 852         case SG_GET_TIMEOUT:    /* N.B. User receives timeout as return value */
 853                                 /* strange ..., for backward compatibility */
 854                 return sfp->timeout_user;
 855         case SG_SET_FORCE_LOW_DMA:
 856                 result = get_user(val, ip);
 857                 if (result)
 858                         return result;
 859                 if (val) {
 860                         sfp->low_dma = 1;
 861                         if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
 862                                 val = (int) sfp->reserve.bufflen;
 863                                 sg_remove_scat(&sfp->reserve);
 864                                 sg_build_reserve(sfp, val);
 865                         }
 866                 } else {
 867                         if (sdp->detached)
 868                                 return -ENODEV;
 869                         sfp->low_dma = sdp->device->host->unchecked_isa_dma;
 870                 }
 871                 return 0;
 872         case SG_GET_LOW_DMA:
 873                 return put_user((int) sfp->low_dma, ip);
 874         case SG_GET_SCSI_ID:
 875                 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
 876                         return -EFAULT;
 877                 else {
 878                         sg_scsi_id_t __user *sg_idp = p;
 879
 880                         if (sdp->detached)
 881                                 return -ENODEV;
 882                         __put_user((int) sdp->device->host->host_no,
 883                                    &sg_idp->host_no);
 884                         __put_user((int) sdp->device->channel,
 885                                    &sg_idp->channel);
 886                         __put_user((int) sdp->device->id, &sg_idp->scsi_id);
 887                         __put_user((int) sdp->device->lun, &sg_idp->lun);
 888                         __put_user((int) sdp->device->type, &sg_idp->scsi_type);
 889                         __put_user((short) sdp->device->host->cmd_per_lun,
 890                                    &sg_idp->h_cmd_per_lun);
 891                         __put_user((short) sdp->device->queue_depth,
 892                                    &sg_idp->d_queue_depth);
 893                         __put_user(0, &sg_idp->unused[0]);
 894                         __put_user(0, &sg_idp->unused[1]);
 895                         return 0;
 896                 }
 897         case SG_SET_FORCE_PACK_ID:
 898                 result = get_user(val, ip);
 899                 if (result)
 900                         return result;
 901                 sfp->force_packid = val ? 1 : 0;
 902                 return 0;
 903         case SG_GET_PACK_ID:
 904                 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
 905                         return -EFAULT;
 906                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 907                 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
 908                         if ((1 == srp->done) && (!srp->sg_io_owned)) {
 909                                 read_unlock_irqrestore(&sfp->rq_list_lock,
 910                                                        iflags);
 911                                 __put_user(srp->header.pack_id, ip);
 912                                 return 0;
 913                         }
 914                 }
 915                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 916                 __put_user(-1, ip);
 917                 return 0;
 918         case SG_GET_NUM_WAITING:
 919                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 920                 for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) {
 921                         if ((1 == srp->done) && (!srp->sg_io_owned))
 922                                 ++val;
 923                 }
 924                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 925                 return put_user(val, ip);
 926         case SG_GET_SG_TABLESIZE:
 927                 return put_user(sdp->sg_tablesize, ip);
 928         case SG_SET_RESERVED_SIZE:
 929                 result = get_user(val, ip);
 930                 if (result)
 931                         return result;
 932                 if (val < 0)
 933                         return -EINVAL;
 934                 if (val != sfp->reserve.bufflen) {
 935                         if (sg_res_in_use(sfp) || sfp->mmap_called)
 936                                 return -EBUSY;
 937                         sg_remove_scat(&sfp->reserve);
 938                         sg_build_reserve(sfp, val);
 939                 }
 940                 return 0;
 941         case SG_GET_RESERVED_SIZE:
 942                 val = (int) sfp->reserve.bufflen;
 943                 return put_user(val, ip);
 944         case SG_SET_COMMAND_Q:
 945                 result = get_user(val, ip);
 946                 if (result)
 947                         return result;
 948                 sfp->cmd_q = val ? 1 : 0;
 949                 return 0;
 950         case SG_GET_COMMAND_Q:
 951                 return put_user((int) sfp->cmd_q, ip);
 952         case SG_SET_KEEP_ORPHAN:
 953                 result = get_user(val, ip);
 954                 if (result)
 955                         return result;
 956                 sfp->keep_orphan = val;
 957                 return 0;
 958         case SG_GET_KEEP_ORPHAN:
 959                 return put_user((int) sfp->keep_orphan, ip);
 960         case SG_NEXT_CMD_LEN:
 961                 result = get_user(val, ip);
 962                 if (result)
 963                         return result;
 964                 sfp->next_cmd_len = (val > 0) ? val : 0;
 965                 return 0;
 966         case SG_GET_VERSION_NUM:
 967                 return put_user(sg_version_num, ip);
 968         case SG_GET_ACCESS_COUNT:
 969                 /* faked - we don't have a real access count anymore */
 970                 val = (sdp->device ? 1 : 0);
 971                 return put_user(val, ip);
 972         case SG_GET_REQUEST_TABLE:
 973                 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
 974                         return -EFAULT;
 975                 else {
 976                         sg_req_info_t *rinfo;
 977                         unsigned int ms;
 978
 979                         rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
 980                                                                 GFP_KERNEL);
 981                         if (!rinfo)
 982                                 return -ENOMEM;
 983                         read_lock_irqsave(&sfp->rq_list_lock, iflags);
 984                         for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE;
 985                              ++val, srp = srp ? srp->nextrp : srp) {
 986                                 memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
 987                                 if (srp) {
 988                                         rinfo[val].req_state = srp->done + 1;
 989                                         rinfo[val].problem =
 990                                             srp->header.masked_status &
 991                                             srp->header.host_status &
 992                                             srp->header.driver_status;
 993                                         if (srp->done)
 994                                                 rinfo[val].duration =
 995                                                         srp->header.duration;
 996                                         else {
 997                                                 ms = jiffies_to_msecs(jiffies);
 998                                                 rinfo[val].duration =
 999                                                     (ms > srp->header.duration) ?
1000                                                     (ms - srp->header.duration) : 0;
1001                                         }
1002                                         rinfo[val].orphan = srp->orphan;
1003                                         rinfo[val].sg_io_owned =
1004                                                         srp->sg_io_owned;
1005                                         rinfo[val].pack_id =
1006                                                         srp->header.pack_id;
1007                                         rinfo[val].usr_ptr =
1008                                                         srp->header.usr_ptr;
1009                                 }
1010                         }
1011                         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1012                         result = __copy_to_user(p, rinfo,
1013                                                 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1014                         result = result ? -EFAULT : 0;
1015                         kfree(rinfo);
1016                         return result;
1017                 }
1018         case SG_EMULATED_HOST:
1019                 if (sdp->detached)
1020                         return -ENODEV;
1021                 return put_user(sdp->device->host->hostt->emulated, ip);
1022         case SG_SCSI_RESET:
1023                 if (sdp->detached)
1024                         return -ENODEV;
1025                 if (filp->f_flags & O_NONBLOCK) {
1026                         if (scsi_host_in_recovery(sdp->device->host))
1027                                 return -EBUSY;
1028                 } else if (!scsi_block_when_processing_errors(sdp->device))
1029                         return -EBUSY;
1030                 result = get_user(val, ip);
1031                 if (result)
1032                         return result;
1033                 if (SG_SCSI_RESET_NOTHING == val)
1034                         return 0;
1035                 switch (val) {
1036                 case SG_SCSI_RESET_DEVICE:
1037                         val = SCSI_TRY_RESET_DEVICE;
1038                         break;
1039                 case SG_SCSI_RESET_BUS:
1040                         val = SCSI_TRY_RESET_BUS;
1041                         break;
1042                 case SG_SCSI_RESET_HOST:
1043                         val = SCSI_TRY_RESET_HOST;
1044                         break;
1045                 default:
1046                         return -EINVAL;
1047                 }
1048                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1049                         return -EACCES;
1050                 return (scsi_reset_provider(sdp->device, val) ==
1051                         SUCCESS) ? 0 : -EIO;
1052         case SCSI_IOCTL_SEND_COMMAND:
1053                 if (sdp->detached)
1054                         return -ENODEV;
1055                 if (read_only) {
1056                         unsigned char opcode = WRITE_6;
1057                         Scsi_Ioctl_Command __user *siocp = p;
1058
1059                         if (copy_from_user(&opcode, siocp->data, 1))
1060                                 return -EFAULT;
1061                         if (!sg_allow_access(opcode, sdp->device->type))
1062                                 return -EPERM;
1063                 }
1064                 return scsi_ioctl_send_command(sdp->device, p);
1065         case SG_SET_DEBUG:
1066                 result = get_user(val, ip);
1067                 if (result)
1068                         return result;
1069                 sdp->sgdebug = (char) val;
1070                 return 0;
1071         case SCSI_IOCTL_GET_IDLUN:
1072         case SCSI_IOCTL_GET_BUS_NUMBER:
1073         case SCSI_IOCTL_PROBE_HOST:
1074         case SG_GET_TRANSFORM:
1075                 if (sdp->detached)
1076                         return -ENODEV;
1077                 return scsi_ioctl(sdp->device, cmd_in, p);
1078         default:
1079                 if (read_only)
1080                         return -EPERM;  /* don't know so take safe approach */
1081                 return scsi_ioctl(sdp->device, cmd_in, p);
1082         }
1083 }
1084
1085 #ifdef CONFIG_COMPAT
1086 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1087 {
1088         Sg_device *sdp;
1089         Sg_fd *sfp;
1090         struct scsi_device *sdev;
1091
1092         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1093                 return -ENXIO;
1094
1095         sdev = sdp->device;
1096         if (sdev->host->hostt->compat_ioctl) {
1097                 int ret;
1098
1099                 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1100
1101                 return ret;
1102         }
1103
1104         return -ENOIOCTLCMD;
1105 }
1106 #endif
1107
1108 static unsigned int
1109 sg_poll(struct file *filp, poll_table * wait)
1110 {
1111         unsigned int res = 0;
1112         Sg_device *sdp;
1113         Sg_fd *sfp;
1114         Sg_request *srp;
1115         int count = 0;
1116         unsigned long iflags;
1117
1118         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))
1119             || sfp->closed)
1120                 return POLLERR;
1121         poll_wait(filp, &sfp->read_wait, wait);
1122         read_lock_irqsave(&sfp->rq_list_lock, iflags);
1123         for (srp = sfp->headrp; srp; srp = srp->nextrp) {
1124                 /* if any read waiting, flag it */
1125                 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1126                         res = POLLIN | POLLRDNORM;
1127                 ++count;
1128         }
1129         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1130
1131         if (sdp->detached)
1132                 res |= POLLHUP;
1133         else if (!sfp->cmd_q) {
1134                 if (0 == count)
1135                         res |= POLLOUT | POLLWRNORM;
1136         } else if (count < SG_MAX_QUEUE)
1137                 res |= POLLOUT | POLLWRNORM;
1138         SCSI_LOG_TIMEOUT(3, printk("sg_poll: %s, res=0x%x\n",
1139                                    sdp->disk->disk_name, (int) res));
1140         return res;
1141 }
1142
1143 static int
1144 sg_fasync(int fd, struct file *filp, int mode)
1145 {
1146         int retval;
1147         Sg_device *sdp;
1148         Sg_fd *sfp;
1149
1150         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1151                 return -ENXIO;
1152         SCSI_LOG_TIMEOUT(3, printk("sg_fasync: %s, mode=%d\n",
1153                                    sdp->disk->disk_name, mode));
1154
1155         retval = fasync_helper(fd, filp, mode, &sfp->async_qp);
1156         return (retval < 0) ? retval : 0;
1157 }
1158
1159 static inline unsigned char *
1160 sg_scatg2virt(const struct scatterlist *sclp)
1161 {
1162         return (sclp && sclp->page) ?
1163             (unsigned char *) page_address(sclp->page) + sclp->offset : NULL;
1164 }
1165
1166 /* When startFinish==1 increments page counts for pages other than the
1167    first of scatter gather elements obtained from __get_free_pages().
1168    When startFinish==0 decrements ... */
1169 static void
1170 sg_rb_correct4mmap(Sg_scatter_hold * rsv_schp, int startFinish)
1171 {
1172         void *page_ptr;
1173         struct page *page;
1174         int k, m;
1175
1176         SCSI_LOG_TIMEOUT(3, printk("sg_rb_correct4mmap: startFinish=%d, scatg=%d\n",
1177                                    startFinish, rsv_schp->k_use_sg));
1178         /* N.B. correction _not_ applied to base page of each allocation */
1179         if (rsv_schp->k_use_sg) {       /* reserve buffer is a scatter gather list */
1180                 struct scatterlist *sclp = rsv_schp->buffer;
1181
1182                 for (k = 0; k < rsv_schp->k_use_sg; ++k, ++sclp) {
1183                         for (m = PAGE_SIZE; m < sclp->length; m += PAGE_SIZE) {
1184                                 page_ptr = sg_scatg2virt(sclp) + m;
1185                                 page = virt_to_page(page_ptr);
1186                                 if (startFinish)
1187                                         get_page(page);
1188                                 else {
1189                                         if (page_count(page) > 0)
1190                                                 __put_page(page);
1191                                 }
1192                         }
1193                 }
1194         } else {                /* reserve buffer is just a single allocation */
1195                 for (m = PAGE_SIZE; m < rsv_schp->bufflen; m += PAGE_SIZE) {
1196                         page_ptr = (unsigned char *) rsv_schp->buffer + m;
1197                         page = virt_to_page(page_ptr);
1198                         if (startFinish)
1199                                 get_page(page);
1200                         else {
1201                                 if (page_count(page) > 0)
1202                                         __put_page(page);
1203                         }
1204                 }
1205         }
1206 }
1207
1208 static struct page *
1209 sg_vma_nopage(struct vm_area_struct *vma, unsigned long addr, int *type)
1210 {
1211         Sg_fd *sfp;
1212         struct page *page = NOPAGE_SIGBUS;
1213         void *page_ptr = NULL;
1214         unsigned long offset;
1215         Sg_scatter_hold *rsv_schp;
1216
1217         if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1218                 return page;
1219         rsv_schp = &sfp->reserve;
1220         offset = addr - vma->vm_start;
1221         if (offset >= rsv_schp->bufflen)
1222                 return page;
1223         SCSI_LOG_TIMEOUT(3, printk("sg_vma_nopage: offset=%lu, scatg=%d\n",
1224                                    offset, rsv_schp->k_use_sg));
1225         if (rsv_schp->k_use_sg) {       /* reserve buffer is a scatter gather list */
1226                 int k;
1227                 unsigned long sa = vma->vm_start;
1228                 unsigned long len;
1229                 struct scatterlist *sclp = rsv_schp->buffer;
1230
1231                 for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
1232                      ++k, ++sclp) {
1233                         len = vma->vm_end - sa;
1234                         len = (len < sclp->length) ? len : sclp->length;
1235                         if (offset < len) {
1236                                 page_ptr = sg_scatg2virt(sclp) + offset;
1237                                 page = virt_to_page(page_ptr);
1238                                 get_page(page); /* increment page count */
1239                                 break;
1240                         }
1241                         sa += len;
1242                         offset -= len;
1243                 }
1244         } else {                /* reserve buffer is just a single allocation */
1245                 page_ptr = (unsigned char *) rsv_schp->buffer + offset;
1246                 page = virt_to_page(page_ptr);
1247                 get_page(page); /* increment page count */
1248         }
1249         if (type)
1250                 *type = VM_FAULT_MINOR;
1251         return page;
1252 }
1253
1254 static struct vm_operations_struct sg_mmap_vm_ops = {
1255         .nopage = sg_vma_nopage,
1256 };
1257
1258 static int
1259 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1260 {
1261         Sg_fd *sfp;
1262         unsigned long req_sz;
1263         Sg_scatter_hold *rsv_schp;
1264
1265         if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1266                 return -ENXIO;
1267         req_sz = vma->vm_end - vma->vm_start;
1268         SCSI_LOG_TIMEOUT(3, printk("sg_mmap starting, vm_start=%p, len=%d\n",
1269                                    (void *) vma->vm_start, (int) req_sz));
1270         if (vma->vm_pgoff)
1271                 return -EINVAL; /* want no offset */
1272         rsv_schp = &sfp->reserve;
1273         if (req_sz > rsv_schp->bufflen)
1274                 return -ENOMEM; /* cannot map more than reserved buffer */
1275
1276         if (rsv_schp->k_use_sg) { /* reserve buffer is a scatter gather list */
1277                 int k;
1278                 unsigned long sa = vma->vm_start;
1279                 unsigned long len;
1280                 struct scatterlist *sclp = rsv_schp->buffer;
1281
1282                 for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
1283                      ++k, ++sclp) {
1284                         if (0 != sclp->offset)
1285                                 return -EFAULT; /* non page aligned memory ?? */
1286                         len = vma->vm_end - sa;
1287                         len = (len < sclp->length) ? len : sclp->length;
1288                         sa += len;
1289                 }
1290         } else {        /* reserve buffer is just a single allocation */
1291                 if ((unsigned long) rsv_schp->buffer & (PAGE_SIZE - 1))
1292                         return -EFAULT; /* non page aligned memory ?? */
1293         }
1294         if (0 == sfp->mmap_called) {
1295                 sg_rb_correct4mmap(rsv_schp, 1);        /* do only once per fd lifetime */
1296                 sfp->mmap_called = 1;
1297         }
1298         vma->vm_flags |= VM_RESERVED;
1299         vma->vm_private_data = sfp;
1300         vma->vm_ops = &sg_mmap_vm_ops;
1301         return 0;
1302 }
1303
1304 /* This function is a "bottom half" handler that is called by the
1305  * mid level when a command is completed (or has failed). */
1306 static void
1307 sg_cmd_done(Scsi_Cmnd * SCpnt)
1308 {
1309         Scsi_Request *SRpnt = NULL;
1310         Sg_device *sdp = NULL;
1311         Sg_fd *sfp;
1312         Sg_request *srp = NULL;
1313         unsigned long iflags;
1314         unsigned int ms;
1315
1316         if (SCpnt && (SRpnt = SCpnt->sc_request))
1317                 srp = (Sg_request *) SRpnt->upper_private_data;
1318         if (NULL == srp) {
1319                 printk(KERN_ERR "sg_cmd_done: NULL request\n");
1320                 if (SRpnt)
1321                         scsi_release_request(SRpnt);
1322                 return;
1323         }
1324         sfp = srp->parentfp;
1325         if (sfp)
1326                 sdp = sfp->parentdp;
1327         if ((NULL == sdp) || sdp->detached) {
1328                 printk(KERN_INFO "sg_cmd_done: device detached\n");
1329                 scsi_release_request(SRpnt);
1330                 return;
1331         }
1332
1333         /* First transfer ownership of data buffers to sg_device object. */
1334         srp->data.k_use_sg = SRpnt->sr_use_sg;
1335         srp->data.sglist_len = SRpnt->sr_sglist_len;
1336         srp->data.bufflen = SRpnt->sr_bufflen;
1337         srp->data.buffer = SRpnt->sr_buffer;
1338         /* now clear out request structure */
1339         SRpnt->sr_use_sg = 0;
1340         SRpnt->sr_sglist_len = 0;
1341         SRpnt->sr_bufflen = 0;
1342         SRpnt->sr_buffer = NULL;
1343         SRpnt->sr_underflow = 0;
1344         SRpnt->sr_request->rq_disk = NULL; /* "sg" _disowns_ request blk */
1345
1346         srp->my_cmdp = NULL;
1347
1348         SCSI_LOG_TIMEOUT(4, printk("sg_cmd_done: %s, pack_id=%d, res=0x%x\n",
1349                 sdp->disk->disk_name, srp->header.pack_id, (int) SRpnt->sr_result));
1350         srp->header.resid = SCpnt->resid;
1351         ms = jiffies_to_msecs(jiffies);
1352         srp->header.duration = (ms > srp->header.duration) ?
1353                                 (ms - srp->header.duration) : 0;
1354         if (0 != SRpnt->sr_result) {
1355                 struct scsi_sense_hdr sshdr;
1356
1357                 memcpy(srp->sense_b, SRpnt->sr_sense_buffer,
1358                        sizeof (srp->sense_b));
1359                 srp->header.status = 0xff & SRpnt->sr_result;
1360                 srp->header.masked_status = status_byte(SRpnt->sr_result);
1361                 srp->header.msg_status = msg_byte(SRpnt->sr_result);
1362                 srp->header.host_status = host_byte(SRpnt->sr_result);
1363                 srp->header.driver_status = driver_byte(SRpnt->sr_result);
1364                 if ((sdp->sgdebug > 0) &&
1365                     ((CHECK_CONDITION == srp->header.masked_status) ||
1366                      (COMMAND_TERMINATED == srp->header.masked_status)))
1367                         scsi_print_req_sense("sg_cmd_done", SRpnt);
1368
1369                 /* Following if statement is a patch supplied by Eric Youngdale */
1370                 if (driver_byte(SRpnt->sr_result) != 0
1371                     && scsi_command_normalize_sense(SCpnt, &sshdr)
1372                     && !scsi_sense_is_deferred(&sshdr)
1373                     && sshdr.sense_key == UNIT_ATTENTION
1374                     && sdp->device->removable) {
1375                         /* Detected possible disc change. Set the bit - this */
1376                         /* may be used if there are filesystems using this device */
1377                         sdp->device->changed = 1;
1378                 }
1379         }
1380         /* Rely on write phase to clean out srp status values, so no "else" */
1381
1382         scsi_release_request(SRpnt);
1383         SRpnt = NULL;
1384         if (sfp->closed) {      /* whoops this fd already released, cleanup */
1385                 SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, freeing ...\n"));
1386                 sg_finish_rem_req(srp);
1387                 srp = NULL;
1388                 if (NULL == sfp->headrp) {
1389                         SCSI_LOG_TIMEOUT(1, printk("sg...bh: already closed, final cleanup\n"));
1390                         if (0 == sg_remove_sfp(sdp, sfp)) {     /* device still present */
1391                                 scsi_device_put(sdp->device);
1392                         }
1393                         sfp = NULL;
1394                 }
1395         } else if (srp && srp->orphan) {
1396                 if (sfp->keep_orphan)
1397                         srp->sg_io_owned = 0;
1398                 else {
1399                         sg_finish_rem_req(srp);
1400                         srp = NULL;
1401                 }
1402         }
1403         if (sfp && srp) {
1404                 /* Now wake up any sg_read() that is waiting for this packet. */
1405                 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1406                 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1407                 srp->done = 1;
1408                 wake_up_interruptible(&sfp->read_wait);
1409                 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1410         }
1411 }
1412
1413 static struct file_operations sg_fops = {
1414         .owner = THIS_MODULE,
1415         .read = sg_read,
1416         .write = sg_write,
1417         .poll = sg_poll,
1418         .ioctl = sg_ioctl,
1419 #ifdef CONFIG_COMPAT
1420         .compat_ioctl = sg_compat_ioctl,
1421 #endif
1422         .open = sg_open,
1423         .mmap = sg_mmap,
1424         .release = sg_release,
1425         .fasync = sg_fasync,
1426 };
1427
1428 static struct class *sg_sysfs_class;
1429
1430 static int sg_sysfs_valid = 0;
1431
1432 static int sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1433 {
1434         Sg_device *sdp;
1435         unsigned long iflags;
1436         void *old_sg_dev_arr = NULL;
1437         int k, error;
1438
1439         sdp = kmalloc(sizeof(Sg_device), GFP_KERNEL);
1440         if (!sdp) {
1441                 printk(KERN_WARNING "kmalloc Sg_device failure\n");
1442                 return -ENOMEM;
1443         }
1444
1445         write_lock_irqsave(&sg_dev_arr_lock, iflags);
1446         if (unlikely(sg_nr_dev >= sg_dev_max)) {        /* try to resize */
1447                 Sg_device **tmp_da;
1448                 int tmp_dev_max = sg_nr_dev + SG_DEV_ARR_LUMP;
1449                 write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1450
1451                 tmp_da = kmalloc(tmp_dev_max * sizeof(Sg_device *), GFP_KERNEL);
1452                 if (unlikely(!tmp_da))
1453                         goto expand_failed;
1454
1455                 write_lock_irqsave(&sg_dev_arr_lock, iflags);
1456                 memset(tmp_da, 0, tmp_dev_max * sizeof(Sg_device *));
1457                 memcpy(tmp_da, sg_dev_arr, sg_dev_max * sizeof(Sg_device *));
1458                 old_sg_dev_arr = sg_dev_arr;
1459                 sg_dev_arr = tmp_da;
1460                 sg_dev_max = tmp_dev_max;
1461         }
1462
1463         for (k = 0; k < sg_dev_max; k++)
1464                 if (!sg_dev_arr[k])
1465                         break;
1466         if (unlikely(k >= SG_MAX_DEVS))
1467                 goto overflow;
1468
1469         memset(sdp, 0, sizeof(*sdp));
1470         SCSI_LOG_TIMEOUT(3, printk("sg_alloc: dev=%d \n", k));
1471         sprintf(disk->disk_name, "sg%d", k);
1472         disk->first_minor = k;
1473         sdp->disk = disk;
1474         sdp->device = scsidp;
1475         init_waitqueue_head(&sdp->o_excl_wait);
1476         sdp->sg_tablesize = scsidp->host ? scsidp->host->sg_tablesize : 0;
1477
1478         sg_nr_dev++;
1479         sg_dev_arr[k] = sdp;
1480         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1481         error = k;
1482
1483  out:
1484         if (error < 0)
1485                 kfree(sdp);
1486         kfree(old_sg_dev_arr);
1487         return error;
1488
1489  expand_failed:
1490         printk(KERN_WARNING "sg_alloc: device array cannot be resized\n");
1491         error = -ENOMEM;
1492         goto out;
1493
1494  overflow:
1495         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1496         sdev_printk(KERN_WARNING, scsidp,
1497                     "Unable to attach sg device type=%d, minor "
1498                     "number exceeds %d\n", scsidp->type, SG_MAX_DEVS - 1);
1499         error = -ENODEV;
1500         goto out;
1501 }
1502
1503 static int
1504 sg_add(struct class_device *cl_dev, struct class_interface *cl_intf)
1505 {
1506         struct scsi_device *scsidp = to_scsi_device(cl_dev->dev);
1507         struct gendisk *disk;
1508         Sg_device *sdp = NULL;
1509         struct cdev * cdev = NULL;
1510         int error, k;
1511
1512         disk = alloc_disk(1);
1513         if (!disk) {
1514                 printk(KERN_WARNING "alloc_disk failed\n");
1515                 return -ENOMEM;
1516         }
1517         disk->major = SCSI_GENERIC_MAJOR;
1518
1519         error = -ENOMEM;
1520         cdev = cdev_alloc();
1521         if (!cdev) {
1522                 printk(KERN_WARNING "cdev_alloc failed\n");
1523                 goto out;
1524         }
1525         cdev->owner = THIS_MODULE;
1526         cdev->ops = &sg_fops;
1527
1528         error = sg_alloc(disk, scsidp);
1529         if (error < 0) {
1530                 printk(KERN_WARNING "sg_alloc failed\n");
1531                 goto out;
1532         }
1533         k = error;
1534         sdp = sg_dev_arr[k];
1535
1536         devfs_mk_cdev(MKDEV(SCSI_GENERIC_MAJOR, k),
1537                         S_IFCHR | S_IRUSR | S_IWUSR | S_IRGRP,
1538                         "%s/generic", scsidp->devfs_name);
1539         error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, k), 1);
1540         if (error) {
1541                 devfs_remove("%s/generic", scsidp->devfs_name);
1542                 goto out;
1543         }
1544         sdp->cdev = cdev;
1545         if (sg_sysfs_valid) {
1546                 struct class_device * sg_class_member;
1547
1548                 sg_class_member = class_device_create(sg_sysfs_class, NULL,
1549                                 MKDEV(SCSI_GENERIC_MAJOR, k),
1550                                 cl_dev->dev, "%s",
1551                                 disk->disk_name);
1552                 if (IS_ERR(sg_class_member))
1553                         printk(KERN_WARNING "sg_add: "
1554                                 "class_device_create failed\n");
1555                 class_set_devdata(sg_class_member, sdp);
1556                 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1557                                           &sg_class_member->kobj, "generic");
1558                 if (error)
1559                         printk(KERN_ERR "sg_add: unable to make symlink "
1560                                         "'generic' back to sg%d\n", k);
1561         } else
1562                 printk(KERN_WARNING "sg_add: sg_sys INvalid\n");
1563
1564         sdev_printk(KERN_NOTICE, scsidp,
1565                     "Attached scsi generic sg%d type %d\n", k,scsidp->type);
1566
1567         return 0;
1568
1569 out:
1570         put_disk(disk);
1571         if (cdev)
1572                 cdev_del(cdev);
1573         return error;
1574 }
1575
1576 static void
1577 sg_remove(struct class_device *cl_dev, struct class_interface *cl_intf)
1578 {
1579         struct scsi_device *scsidp = to_scsi_device(cl_dev->dev);
1580         Sg_device *sdp = NULL;
1581         unsigned long iflags;
1582         Sg_fd *sfp;
1583         Sg_fd *tsfp;
1584         Sg_request *srp;
1585         Sg_request *tsrp;
1586         int k, delay;
1587
1588         if (NULL == sg_dev_arr)
1589                 return;
1590         delay = 0;
1591         write_lock_irqsave(&sg_dev_arr_lock, iflags);
1592         for (k = 0; k < sg_dev_max; k++) {
1593                 sdp = sg_dev_arr[k];
1594                 if ((NULL == sdp) || (sdp->device != scsidp))
1595                         continue;       /* dirty but lowers nesting */
1596                 if (sdp->headfp) {
1597                         sdp->detached = 1;
1598                         for (sfp = sdp->headfp; sfp; sfp = tsfp) {
1599                                 tsfp = sfp->nextfp;
1600                                 for (srp = sfp->headrp; srp; srp = tsrp) {
1601                                         tsrp = srp->nextrp;
1602                                         if (sfp->closed || (0 == sg_srp_done(srp, sfp)))
1603                                                 sg_finish_rem_req(srp);
1604                                 }
1605                                 if (sfp->closed) {
1606                                         scsi_device_put(sdp->device);
1607                                         __sg_remove_sfp(sdp, sfp);
1608                                 } else {
1609                                         delay = 1;
1610                                         wake_up_interruptible(&sfp->read_wait);
1611                                         kill_fasync(&sfp->async_qp, SIGPOLL,
1612                                                     POLL_HUP);
1613                                 }
1614                         }
1615                         SCSI_LOG_TIMEOUT(3, printk("sg_detach: dev=%d, dirty\n", k));
1616                         if (NULL == sdp->headfp) {
1617                                 sg_dev_arr[k] = NULL;
1618                         }
1619                 } else {        /* nothing active, simple case */
1620                         SCSI_LOG_TIMEOUT(3, printk("sg_detach: dev=%d\n", k));
1621                         sg_dev_arr[k] = NULL;
1622                 }
1623                 sg_nr_dev--;
1624                 break;
1625         }
1626         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1627
1628         if (sdp) {
1629                 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1630                 class_device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, k));
1631                 cdev_del(sdp->cdev);
1632                 sdp->cdev = NULL;
1633                 devfs_remove("%s/generic", scsidp->devfs_name);
1634                 put_disk(sdp->disk);
1635                 sdp->disk = NULL;
1636                 if (NULL == sdp->headfp)
1637                         kfree((char *) sdp);
1638         }
1639
1640         if (delay)
1641                 msleep(10);     /* dirty detach so delay device destruction */
1642 }
1643
1644 /* Set 'perm' (4th argument) to 0 to disable module_param's definition
1645  * of sysfs parameters (which module_param doesn't yet support).
1646  * Sysfs parameters defined explicitly below.
1647  */
1648 module_param_named(def_reserved_size, def_reserved_size, int, S_IRUGO);
1649 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1650
1651 MODULE_AUTHOR("Douglas Gilbert");
1652 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1653 MODULE_LICENSE("GPL");
1654 MODULE_VERSION(SG_VERSION_STR);
1655
1656 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1657 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1658
1659 static int __init
1660 init_sg(void)
1661 {
1662         int rc;
1663
1664         if (def_reserved_size >= 0)
1665                 sg_big_buff = def_reserved_size;
1666
1667         rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1668                                     SG_MAX_DEVS, "sg");
1669         if (rc)
1670                 return rc;
1671         sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1672         if ( IS_ERR(sg_sysfs_class) ) {
1673                 rc = PTR_ERR(sg_sysfs_class);
1674                 goto err_out;
1675         }
1676         sg_sysfs_valid = 1;
1677         rc = scsi_register_interface(&sg_interface);
1678         if (0 == rc) {
1679 #ifdef CONFIG_SCSI_PROC_FS
1680                 sg_proc_init();
1681 #endif                          /* CONFIG_SCSI_PROC_FS */
1682                 return 0;
1683         }
1684         class_destroy(sg_sysfs_class);
1685 err_out:
1686         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1687         return rc;
1688 }
1689
1690 static void __exit
1691 exit_sg(void)
1692 {
1693 #ifdef CONFIG_SCSI_PROC_FS
1694         sg_proc_cleanup();
1695 #endif                          /* CONFIG_SCSI_PROC_FS */
1696         scsi_unregister_interface(&sg_interface);
1697         class_destroy(sg_sysfs_class);
1698         sg_sysfs_valid = 0;
1699         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1700                                  SG_MAX_DEVS);
1701         kfree((char *)sg_dev_arr);
1702         sg_dev_arr = NULL;
1703         sg_dev_max = 0;
1704 }
1705
1706 static int
1707 sg_start_req(Sg_request * srp)
1708 {
1709         int res;
1710         Sg_fd *sfp = srp->parentfp;
1711         sg_io_hdr_t *hp = &srp->header;
1712         int dxfer_len = (int) hp->dxfer_len;
1713         int dxfer_dir = hp->dxfer_direction;
1714         Sg_scatter_hold *req_schp = &srp->data;
1715         Sg_scatter_hold *rsv_schp = &sfp->reserve;
1716
1717         SCSI_LOG_TIMEOUT(4, printk("sg_start_req: dxfer_len=%d\n", dxfer_len));
1718         if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1719                 return 0;
1720         if (sg_allow_dio && (hp->flags & SG_FLAG_DIRECT_IO) &&
1721             (dxfer_dir != SG_DXFER_UNKNOWN) && (0 == hp->iovec_count) &&
1722             (!sfp->parentdp->device->host->unchecked_isa_dma)) {
1723                 res = sg_build_direct(srp, sfp, dxfer_len);
1724                 if (res <= 0)   /* -ve -> error, 0 -> done, 1 -> try indirect */
1725                         return res;
1726         }
1727         if ((!sg_res_in_use(sfp)) && (dxfer_len <= rsv_schp->bufflen))
1728                 sg_link_reserve(sfp, srp, dxfer_len);
1729         else {
1730                 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1731                 if (res) {
1732                         sg_remove_scat(req_schp);
1733                         return res;
1734                 }
1735         }
1736         return 0;
1737 }
1738
1739 static void
1740 sg_finish_rem_req(Sg_request * srp)
1741 {
1742         Sg_fd *sfp = srp->parentfp;
1743         Sg_scatter_hold *req_schp = &srp->data;
1744
1745         SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n", (int) srp->res_used));
1746         if (srp->res_used)
1747                 sg_unlink_reserve(sfp, srp);
1748         else
1749                 sg_remove_scat(req_schp);
1750         sg_remove_request(sfp, srp);
1751 }
1752
1753 static int
1754 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1755 {
1756         int ret_sz;
1757         int elem_sz = sizeof (struct scatterlist);
1758         int sg_bufflen = tablesize * elem_sz;
1759         int mx_sc_elems = tablesize;
1760
1761         schp->buffer = sg_page_malloc(sg_bufflen, sfp->low_dma, &ret_sz);
1762         if (!schp->buffer)
1763                 return -ENOMEM;
1764         else if (ret_sz != sg_bufflen) {
1765                 sg_bufflen = ret_sz;
1766                 mx_sc_elems = sg_bufflen / elem_sz;
1767         }
1768         schp->sglist_len = sg_bufflen;
1769         memset(schp->buffer, 0, sg_bufflen);
1770         return mx_sc_elems;     /* number of scat_gath elements allocated */
1771 }
1772
1773 #ifdef SG_ALLOW_DIO_CODE
1774 /* vvvvvvvv  following code borrowed from st driver's direct IO vvvvvvvvv */
1775         /* hopefully this generic code will moved to a library */
1776
1777 /* Pin down user pages and put them into a scatter gather list. Returns <= 0 if
1778    - mapping of all pages not successful
1779    - any page is above max_pfn
1780    (i.e., either completely successful or fails)
1781 */
1782 static int
1783 st_map_user_pages(struct scatterlist *sgl, const unsigned int max_pages,
1784                   unsigned long uaddr, size_t count, int rw,
1785                   unsigned long max_pfn)
1786 {
1787         unsigned long end = (uaddr + count + PAGE_SIZE - 1) >> PAGE_SHIFT;
1788         unsigned long start = uaddr >> PAGE_SHIFT;
1789         const int nr_pages = end - start;
1790         int res, i, j;
1791         struct page **pages;
1792
1793         /* User attempted Overflow! */
1794         if ((uaddr + count) < uaddr)
1795                 return -EINVAL;
1796
1797         /* Too big */
1798         if (nr_pages > max_pages)
1799                 return -ENOMEM;
1800
1801         /* Hmm? */
1802         if (count == 0)
1803                 return 0;
1804
1805         if ((pages = kmalloc(max_pages * sizeof(*pages), GFP_ATOMIC)) == NULL)
1806                 return -ENOMEM;
1807
1808         /* Try to fault in all of the necessary pages */
1809         down_read(&current->mm->mmap_sem);
1810         /* rw==READ means read from drive, write into memory area */
1811         res = get_user_pages(
1812                 current,
1813                 current->mm,
1814                 uaddr,
1815                 nr_pages,
1816                 rw == READ,
1817                 0, /* don't force */
1818                 pages,
1819                 NULL);
1820         up_read(&current->mm->mmap_sem);
1821
1822         /* Errors and no page mapped should return here */
1823         if (res < nr_pages)
1824                 goto out_unmap;
1825
1826         for (i=0; i < nr_pages; i++) {
1827                 /* FIXME: flush superflous for rw==READ,
1828                  * probably wrong function for rw==WRITE
1829                  */
1830                 flush_dcache_page(pages[i]);
1831                 if (page_to_pfn(pages[i]) > max_pfn)
1832                         goto out_unlock;
1833                 /* ?? Is locking needed? I don't think so */
1834                 /* if (TestSetPageLocked(pages[i]))
1835                    goto out_unlock; */
1836         }
1837
1838         /* Populate the scatter/gather list */
1839         sgl[0].page = pages[0];
1840         sgl[0].offset = uaddr & ~PAGE_MASK;
1841         if (nr_pages > 1) {
1842                 sgl[0].length = PAGE_SIZE - sgl[0].offset;
1843                 count -= sgl[0].length;
1844                 for (i=1; i < nr_pages ; i++) {
1845                         sgl[i].offset = 0;
1846                         sgl[i].page = pages[i];
1847                         sgl[i].length = count < PAGE_SIZE ? count : PAGE_SIZE;
1848                         count -= PAGE_SIZE;
1849                 }
1850         }
1851         else {
1852                 sgl[0].length = count;
1853         }
1854
1855         kfree(pages);
1856         return nr_pages;
1857
1858  out_unlock:
1859         /* for (j=0; j < i; j++)
1860            unlock_page(pages[j]); */
1861         res = 0;
1862  out_unmap:
1863         if (res > 0)
1864                 for (j=0; j < res; j++)
1865                         page_cache_release(pages[j]);
1866         kfree(pages);
1867         return res;
1868 }
1869
1870
1871 /* And unmap them... */
1872 static int
1873 st_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_pages,
1874                     int dirtied)
1875 {
1876         int i;
1877
1878         for (i=0; i < nr_pages; i++) {
1879                 struct page *page = sgl[i].page;
1880
1881                 /* XXX: just for debug. Remove when PageReserved is removed */
1882                 BUG_ON(PageReserved(page));
1883                 if (dirtied)
1884                         SetPageDirty(page);
1885                 /* unlock_page(page); */
1886                 /* FIXME: cache flush missing for rw==READ
1887                  * FIXME: call the correct reference counting function
1888                  */
1889                 page_cache_release(page);
1890         }
1891
1892         return 0;
1893 }
1894
1895 /* ^^^^^^^^  above code borrowed from st driver's direct IO ^^^^^^^^^ */
1896 #endif
1897
1898
1899 /* Returns: -ve -> error, 0 -> done, 1 -> try indirect */
1900 static int
1901 sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len)
1902 {
1903 #ifdef SG_ALLOW_DIO_CODE
1904         sg_io_hdr_t *hp = &srp->header;
1905         Sg_scatter_hold *schp = &srp->data;
1906         int sg_tablesize = sfp->parentdp->sg_tablesize;
1907         struct scatterlist *sgl;
1908         int mx_sc_elems, res;
1909         struct scsi_device *sdev = sfp->parentdp->device;
1910
1911         if (((unsigned long)hp->dxferp &
1912                         queue_dma_alignment(sdev->request_queue)) != 0)
1913                 return 1;
1914         mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1915         if (mx_sc_elems <= 0) {
1916                 return 1;
1917         }
1918         sgl = (struct scatterlist *)schp->buffer;
1919         res = st_map_user_pages(sgl, mx_sc_elems, (unsigned long)hp->dxferp, dxfer_len,
1920                                 (SG_DXFER_TO_DEV == hp->dxfer_direction) ? 1 : 0, ULONG_MAX);
1921         if (res <= 0)
1922                 return 1;
1923         schp->k_use_sg = res;
1924         schp->dio_in_use = 1;
1925         hp->info |= SG_INFO_DIRECT_IO;
1926         return 0;
1927 #else
1928         return 1;
1929 #endif
1930 }
1931
1932 static int
1933 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1934 {
1935         int ret_sz;
1936         int blk_size = buff_size;
1937         unsigned char *p = NULL;
1938
1939         if ((blk_size < 0) || (!sfp))
1940                 return -EFAULT;
1941         if (0 == blk_size)
1942                 ++blk_size;     /* don't know why */
1943 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1944         blk_size = (blk_size + SG_SECTOR_MSK) & (~SG_SECTOR_MSK);
1945         SCSI_LOG_TIMEOUT(4, printk("sg_build_indirect: buff_size=%d, blk_size=%d\n",
1946                                    buff_size, blk_size));
1947         if (blk_size <= SG_SCATTER_SZ) {
1948                 p = sg_page_malloc(blk_size, sfp->low_dma, &ret_sz);
1949                 if (!p)
1950                         return -ENOMEM;
1951                 if (blk_size == ret_sz) {       /* got it on the first attempt */
1952                         schp->k_use_sg = 0;
1953                         schp->buffer = p;
1954                         schp->bufflen = blk_size;
1955                         schp->b_malloc_len = blk_size;
1956                         return 0;
1957                 }
1958         } else {
1959                 p = sg_page_malloc(SG_SCATTER_SZ, sfp->low_dma, &ret_sz);
1960                 if (!p)
1961                         return -ENOMEM;
1962         }
1963 /* Want some local declarations, so start new block ... */
1964         {                       /* lets try and build a scatter gather list */
1965                 struct scatterlist *sclp;
1966                 int k, rem_sz, num;
1967                 int mx_sc_elems;
1968                 int sg_tablesize = sfp->parentdp->sg_tablesize;
1969                 int first = 1;
1970
1971                 /* N.B. ret_sz carried into this block ... */
1972                 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1973                 if (mx_sc_elems < 0)
1974                         return mx_sc_elems;     /* most likely -ENOMEM */
1975
1976                 for (k = 0, sclp = schp->buffer, rem_sz = blk_size;
1977                      (rem_sz > 0) && (k < mx_sc_elems);
1978                      ++k, rem_sz -= ret_sz, ++sclp) {
1979                         if (first)
1980                                 first = 0;
1981                         else {
1982                                 num =
1983                                     (rem_sz >
1984                                      SG_SCATTER_SZ) ? SG_SCATTER_SZ : rem_sz;
1985                                 p = sg_page_malloc(num, sfp->low_dma, &ret_sz);
1986                                 if (!p)
1987                                         break;
1988                         }
1989                         sg_set_buf(sclp, p, ret_sz);
1990
1991                         SCSI_LOG_TIMEOUT(5, printk("sg_build_build: k=%d, a=0x%p, len=%d\n",
1992                                           k, sg_scatg2virt(sclp), ret_sz));
1993                 }               /* end of for loop */
1994                 schp->k_use_sg = k;
1995                 SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, rem_sz=%d\n", k, rem_sz));
1996                 schp->bufflen = blk_size;
1997                 if (rem_sz > 0) /* must have failed */
1998                         return -ENOMEM;
1999         }
2000         return 0;
2001 }
2002
2003 static int
2004 sg_write_xfer(Sg_request * srp)
2005 {
2006         sg_io_hdr_t *hp = &srp->header;
2007         Sg_scatter_hold *schp = &srp->data;
2008         int num_xfer = 0;
2009         int j, k, onum, usglen, ksglen, res;
2010         int iovec_count = (int) hp->iovec_count;
2011         int dxfer_dir = hp->dxfer_direction;
2012         unsigned char *p;
2013         unsigned char __user *up;
2014         int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
2015
2016         if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_TO_DEV == dxfer_dir) ||
2017             (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
2018                 num_xfer = (int) (new_interface ? hp->dxfer_len : hp->flags);
2019                 if (schp->bufflen < num_xfer)
2020                         num_xfer = schp->bufflen;
2021         }
2022         if ((num_xfer <= 0) || (schp->dio_in_use) ||
2023             (new_interface
2024              && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
2025                 return 0;
2026
2027         SCSI_LOG_TIMEOUT(4, printk("sg_write_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
2028                           num_xfer, iovec_count, schp->k_use_sg));
2029         if (iovec_count) {
2030                 onum = iovec_count;
2031                 if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum))
2032                         return -EFAULT;
2033         } else
2034                 onum = 1;
2035
2036         if (0 == schp->k_use_sg) {      /* kernel has single buffer */
2037                 for (j = 0, p = schp->buffer; j < onum; ++j) {
2038                         res = sg_u_iovec(hp, iovec_count, j, 1, &usglen, &up);
2039                         if (res)
2040                                 return res;
2041                         usglen = (num_xfer > usglen) ? usglen : num_xfer;
2042                         if (__copy_from_user(p, up, usglen))
2043                                 return -EFAULT;
2044                         p += usglen;
2045                         num_xfer -= usglen;
2046                         if (num_xfer <= 0)
2047                                 return 0;
2048                 }
2049         } else {                /* kernel using scatter gather list */
2050                 struct scatterlist *sclp = (struct scatterlist *) schp->buffer;
2051
2052                 ksglen = (int) sclp->length;
2053                 p = sg_scatg2virt(sclp);
2054                 for (j = 0, k = 0; j < onum; ++j) {
2055                         res = sg_u_iovec(hp, iovec_count, j, 1, &usglen, &up);
2056                         if (res)
2057                                 return res;
2058
2059                         for (; p; ++sclp, ksglen = (int) sclp->length,
2060                                   p = sg_scatg2virt(sclp)) {
2061                                 if (usglen <= 0)
2062                                         break;
2063                                 if (ksglen > usglen) {
2064                                         if (usglen >= num_xfer) {
2065                                                 if (__copy_from_user
2066                                                     (p, up, num_xfer))
2067                                                         return -EFAULT;
2068                                                 return 0;
2069                                         }
2070                                         if (__copy_from_user(p, up, usglen))
2071                                                 return -EFAULT;
2072                                         p += usglen;
2073                                         ksglen -= usglen;
2074                                         break;
2075                                 } else {
2076                                         if (ksglen >= num_xfer) {
2077                                                 if (__copy_from_user
2078                                                     (p, up, num_xfer))
2079                                                         return -EFAULT;
2080                                                 return 0;
2081                                         }
2082                                         if (__copy_from_user(p, up, ksglen))
2083                                                 return -EFAULT;
2084                                         up += ksglen;
2085                                         usglen -= ksglen;
2086                                 }
2087                                 ++k;
2088                                 if (k >= schp->k_use_sg)
2089                                         return 0;
2090                         }
2091                 }
2092         }
2093         return 0;
2094 }
2095
2096 static int
2097 sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
2098            int wr_xf, int *countp, unsigned char __user **up)
2099 {
2100         int num_xfer = (int) hp->dxfer_len;
2101         unsigned char __user *p = hp->dxferp;
2102         int count;
2103
2104         if (0 == sg_num) {
2105                 if (wr_xf && ('\0' == hp->interface_id))
2106                         count = (int) hp->flags;        /* holds "old" input_size */
2107                 else
2108                         count = num_xfer;
2109         } else {
2110                 sg_iovec_t iovec;
2111                 if (__copy_from_user(&iovec, p + ind*SZ_SG_IOVEC, SZ_SG_IOVEC))
2112                         return -EFAULT;
2113                 p = iovec.iov_base;
2114                 count = (int) iovec.iov_len;
2115         }
2116         if (!access_ok(wr_xf ? VERIFY_READ : VERIFY_WRITE, p, count))
2117                 return -EFAULT;
2118         if (up)
2119                 *up = p;
2120         if (countp)
2121                 *countp = count;
2122         return 0;
2123 }
2124
2125 static void
2126 sg_remove_scat(Sg_scatter_hold * schp)
2127 {
2128         SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
2129         if (schp->buffer && (schp->sglist_len > 0)) {
2130                 struct scatterlist *sclp = (struct scatterlist *) schp->buffer;
2131
2132                 if (schp->dio_in_use) {
2133 #ifdef SG_ALLOW_DIO_CODE
2134                         st_unmap_user_pages(sclp, schp->k_use_sg, TRUE);
2135 #endif
2136                 } else {
2137                         int k;
2138
2139                         for (k = 0; (k < schp->k_use_sg) && sg_scatg2virt(sclp);
2140                              ++k, ++sclp) {
2141                                 SCSI_LOG_TIMEOUT(5, printk(
2142                                     "sg_remove_scat: k=%d, a=0x%p, len=%d\n",
2143                                     k, sg_scatg2virt(sclp), sclp->length));
2144                                 sg_page_free(sg_scatg2virt(sclp), sclp->length);
2145                                 sclp->page = NULL;
2146                                 sclp->offset = 0;
2147                                 sclp->length = 0;
2148                         }
2149                 }
2150                 sg_page_free(schp->buffer, schp->sglist_len);
2151         } else if (schp->buffer)
2152                 sg_page_free(schp->buffer, schp->b_malloc_len);
2153         memset(schp, 0, sizeof (*schp));
2154 }
2155
2156 static int
2157 sg_read_xfer(Sg_request * srp)
2158 {
2159         sg_io_hdr_t *hp = &srp->header;
2160         Sg_scatter_hold *schp = &srp->data;
2161         int num_xfer = 0;
2162         int j, k, onum, usglen, ksglen, res;
2163         int iovec_count = (int) hp->iovec_count;
2164         int dxfer_dir = hp->dxfer_direction;
2165         unsigned char *p;
2166         unsigned char __user *up;
2167         int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
2168
2169         if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_FROM_DEV == dxfer_dir)
2170             || (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
2171                 num_xfer = hp->dxfer_len;
2172                 if (schp->bufflen < num_xfer)
2173                         num_xfer = schp->bufflen;
2174         }
2175         if ((num_xfer <= 0) || (schp->dio_in_use) ||
2176             (new_interface
2177              && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
2178                 return 0;
2179
2180         SCSI_LOG_TIMEOUT(4, printk("sg_read_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
2181                           num_xfer, iovec_count, schp->k_use_sg));
2182         if (iovec_count) {
2183                 onum = iovec_count;
2184                 if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum))
2185                         return -EFAULT;
2186         } else
2187                 onum = 1;
2188
2189         if (0 == schp->k_use_sg) {      /* kernel has single buffer */
2190                 for (j = 0, p = schp->buffer; j < onum; ++j) {
2191                         res = sg_u_iovec(hp, iovec_count, j, 0, &usglen, &up);
2192                         if (res)
2193                                 return res;
2194                         usglen = (num_xfer > usglen) ? usglen : num_xfer;
2195                         if (__copy_to_user(up, p, usglen))
2196                                 return -EFAULT;
2197                         p += usglen;
2198                         num_xfer -= usglen;
2199                         if (num_xfer <= 0)
2200                                 return 0;
2201                 }
2202         } else {                /* kernel using scatter gather list */
2203                 struct scatterlist *sclp = (struct scatterlist *) schp->buffer;
2204
2205                 ksglen = (int) sclp->length;
2206                 p = sg_scatg2virt(sclp);
2207                 for (j = 0, k = 0; j < onum; ++j) {
2208                         res = sg_u_iovec(hp, iovec_count, j, 0, &usglen, &up);
2209                         if (res)
2210                                 return res;
2211
2212                         for (; p; ++sclp, ksglen = (int) sclp->length,
2213                                   p = sg_scatg2virt(sclp)) {
2214                                 if (usglen <= 0)
2215                                         break;
2216                                 if (ksglen > usglen) {
2217                                         if (usglen >= num_xfer) {
2218                                                 if (__copy_to_user
2219                                                     (up, p, num_xfer))
2220                                                         return -EFAULT;
2221                                                 return 0;
2222                                         }
2223                                         if (__copy_to_user(up, p, usglen))
2224                                                 return -EFAULT;
2225                                         p += usglen;
2226                                         ksglen -= usglen;
2227                                         break;
2228                                 } else {
2229                                         if (ksglen >= num_xfer) {
2230                                                 if (__copy_to_user
2231                                                     (up, p, num_xfer))
2232                                                         return -EFAULT;
2233                                                 return 0;
2234                                         }
2235                                         if (__copy_to_user(up, p, ksglen))
2236                                                 return -EFAULT;
2237                                         up += ksglen;
2238                                         usglen -= ksglen;
2239                                 }
2240                                 ++k;
2241                                 if (k >= schp->k_use_sg)
2242                                         return 0;
2243                         }
2244                 }
2245         }
2246         return 0;
2247 }
2248
2249 static int
2250 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
2251 {
2252         Sg_scatter_hold *schp = &srp->data;
2253
2254         SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n",
2255                                    num_read_xfer));
2256         if ((!outp) || (num_read_xfer <= 0))
2257                 return 0;
2258         if (schp->k_use_sg > 0) {
2259                 int k, num;
2260                 struct scatterlist *sclp = (struct scatterlist *) schp->buffer;
2261
2262                 for (k = 0; (k < schp->k_use_sg) && sg_scatg2virt(sclp);
2263                      ++k, ++sclp) {
2264                         num = (int) sclp->length;
2265                         if (num > num_read_xfer) {
2266                                 if (__copy_to_user
2267                                     (outp, sg_scatg2virt(sclp), num_read_xfer))
2268                                         return -EFAULT;
2269                                 break;
2270                         } else {
2271                                 if (__copy_to_user
2272                                     (outp, sg_scatg2virt(sclp), num))
2273                                         return -EFAULT;
2274                                 num_read_xfer -= num;
2275                                 if (num_read_xfer <= 0)
2276                                         break;
2277                                 outp += num;
2278                         }
2279                 }
2280         } else {
2281                 if (__copy_to_user(outp, schp->buffer, num_read_xfer))
2282                         return -EFAULT;
2283         }
2284         return 0;
2285 }
2286
2287 static void
2288 sg_build_reserve(Sg_fd * sfp, int req_size)
2289 {
2290         Sg_scatter_hold *schp = &sfp->reserve;
2291
2292         SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
2293         do {
2294                 if (req_size < PAGE_SIZE)
2295                         req_size = PAGE_SIZE;
2296                 if (0 == sg_build_indirect(schp, sfp, req_size))
2297                         return;
2298                 else
2299                         sg_remove_scat(schp);
2300                 req_size >>= 1; /* divide by 2 */
2301         } while (req_size > (PAGE_SIZE / 2));
2302 }
2303
2304 static void
2305 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2306 {
2307         Sg_scatter_hold *req_schp = &srp->data;
2308         Sg_scatter_hold *rsv_schp = &sfp->reserve;
2309
2310         srp->res_used = 1;
2311         SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
2312         size = (size + 1) & (~1);       /* round to even for aha1542 */
2313         if (rsv_schp->k_use_sg > 0) {
2314                 int k, num;
2315                 int rem = size;
2316                 struct scatterlist *sclp =
2317                     (struct scatterlist *) rsv_schp->buffer;
2318
2319                 for (k = 0; k < rsv_schp->k_use_sg; ++k, ++sclp) {
2320                         num = (int) sclp->length;
2321                         if (rem <= num) {
2322                                 if (0 == k) {
2323                                         req_schp->k_use_sg = 0;
2324                                         req_schp->buffer = sg_scatg2virt(sclp);
2325                                 } else {
2326                                         sfp->save_scat_len = num;
2327                                         sclp->length = (unsigned) rem;
2328                                         req_schp->k_use_sg = k + 1;
2329                                         req_schp->sglist_len =
2330                                             rsv_schp->sglist_len;
2331                                         req_schp->buffer = rsv_schp->buffer;
2332                                 }
2333                                 req_schp->bufflen = size;
2334                                 req_schp->b_malloc_len = rsv_schp->b_malloc_len;
2335                                 break;
2336                         } else
2337                                 rem -= num;
2338                 }
2339                 if (k >= rsv_schp->k_use_sg)
2340                         SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
2341         } else {
2342                 req_schp->k_use_sg = 0;
2343                 req_schp->bufflen = size;
2344                 req_schp->buffer = rsv_schp->buffer;
2345                 req_schp->b_malloc_len = rsv_schp->b_malloc_len;
2346         }
2347 }
2348
2349 static void
2350 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2351 {
2352         Sg_scatter_hold *req_schp = &srp->data;
2353         Sg_scatter_hold *rsv_schp = &sfp->reserve;
2354
2355         SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->k_use_sg=%d\n",
2356                                    (int) req_schp->k_use_sg));
2357         if ((rsv_schp->k_use_sg > 0) && (req_schp->k_use_sg > 0)) {
2358                 struct scatterlist *sclp =
2359                     (struct scatterlist *) rsv_schp->buffer;
2360
2361                 if (sfp->save_scat_len > 0)
2362                         (sclp + (req_schp->k_use_sg - 1))->length =
2363                             (unsigned) sfp->save_scat_len;
2364                 else
2365                         SCSI_LOG_TIMEOUT(1, printk ("sg_unlink_reserve: BAD save_scat_len\n"));
2366         }
2367         req_schp->k_use_sg = 0;
2368         req_schp->bufflen = 0;
2369         req_schp->buffer = NULL;
2370         req_schp->sglist_len = 0;
2371         sfp->save_scat_len = 0;
2372         srp->res_used = 0;
2373 }
2374
2375 static Sg_request *
2376 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2377 {
2378         Sg_request *resp;
2379         unsigned long iflags;
2380
2381         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2382         for (resp = sfp->headrp; resp; resp = resp->nextrp) {
2383                 /* look for requests that are ready + not SG_IO owned */
2384                 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2385                     ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2386                         resp->done = 2; /* guard against other readers */
2387                         break;
2388                 }
2389         }
2390         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2391         return resp;
2392 }
2393
2394 #ifdef CONFIG_SCSI_PROC_FS
2395 static Sg_request *
2396 sg_get_nth_request(Sg_fd * sfp, int nth)
2397 {
2398         Sg_request *resp;
2399         unsigned long iflags;
2400         int k;
2401
2402         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2403         for (k = 0, resp = sfp->headrp; resp && (k < nth);
2404              ++k, resp = resp->nextrp) ;
2405         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2406         return resp;
2407 }
2408 #endif
2409
2410 /* always adds to end of list */
2411 static Sg_request *
2412 sg_add_request(Sg_fd * sfp)
2413 {
2414         int k;
2415         unsigned long iflags;
2416         Sg_request *resp;
2417         Sg_request *rp = sfp->req_arr;
2418
2419         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2420         resp = sfp->headrp;
2421         if (!resp) {
2422                 memset(rp, 0, sizeof (Sg_request));
2423                 rp->parentfp = sfp;
2424                 resp = rp;
2425                 sfp->headrp = resp;
2426         } else {
2427                 if (0 == sfp->cmd_q)
2428                         resp = NULL;    /* command queuing disallowed */
2429                 else {
2430                         for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2431                                 if (!rp->parentfp)
2432                                         break;
2433                         }
2434                         if (k < SG_MAX_QUEUE) {
2435                                 memset(rp, 0, sizeof (Sg_request));
2436                                 rp->parentfp = sfp;
2437                                 while (resp->nextrp)
2438                                         resp = resp->nextrp;
2439                                 resp->nextrp = rp;
2440                                 resp = rp;
2441                         } else
2442                                 resp = NULL;
2443                 }
2444         }
2445         if (resp) {
2446                 resp->nextrp = NULL;
2447                 resp->header.duration = jiffies_to_msecs(jiffies);
2448                 resp->my_cmdp = NULL;
2449         }
2450         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2451         return resp;
2452 }
2453
2454 /* Return of 1 for found; 0 for not found */
2455 static int
2456 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2457 {
2458         Sg_request *prev_rp;
2459         Sg_request *rp;
2460         unsigned long iflags;
2461         int res = 0;
2462
2463         if ((!sfp) || (!srp) || (!sfp->headrp))
2464                 return res;
2465         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2466         if (srp->my_cmdp)
2467                 srp->my_cmdp->upper_private_data = NULL;
2468         prev_rp = sfp->headrp;
2469         if (srp == prev_rp) {
2470                 sfp->headrp = prev_rp->nextrp;
2471                 prev_rp->parentfp = NULL;
2472                 res = 1;
2473         } else {
2474                 while ((rp = prev_rp->nextrp)) {
2475                         if (srp == rp) {
2476                                 prev_rp->nextrp = rp->nextrp;
2477                                 rp->parentfp = NULL;
2478                                 res = 1;
2479                                 break;
2480                         }
2481                         prev_rp = rp;
2482                 }
2483         }
2484         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2485         return res;
2486 }
2487
2488 #ifdef CONFIG_SCSI_PROC_FS
2489 static Sg_fd *
2490 sg_get_nth_sfp(Sg_device * sdp, int nth)
2491 {
2492         Sg_fd *resp;
2493         unsigned long iflags;
2494         int k;
2495
2496         read_lock_irqsave(&sg_dev_arr_lock, iflags);
2497         for (k = 0, resp = sdp->headfp; resp && (k < nth);
2498              ++k, resp = resp->nextfp) ;
2499         read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2500         return resp;
2501 }
2502 #endif
2503
2504 static Sg_fd *
2505 sg_add_sfp(Sg_device * sdp, int dev)
2506 {
2507         Sg_fd *sfp;
2508         unsigned long iflags;
2509
2510         sfp = (Sg_fd *) sg_page_malloc(sizeof (Sg_fd), 0, NULL);
2511         if (!sfp)
2512                 return NULL;
2513         memset(sfp, 0, sizeof (Sg_fd));
2514         init_waitqueue_head(&sfp->read_wait);
2515         rwlock_init(&sfp->rq_list_lock);
2516
2517         sfp->timeout = SG_DEFAULT_TIMEOUT;
2518         sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2519         sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2520         sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
2521             sdp->device->host->unchecked_isa_dma : 1;
2522         sfp->cmd_q = SG_DEF_COMMAND_Q;
2523         sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2524         sfp->parentdp = sdp;
2525         write_lock_irqsave(&sg_dev_arr_lock, iflags);
2526         if (!sdp->headfp)
2527                 sdp->headfp = sfp;
2528         else {                  /* add to tail of existing list */
2529                 Sg_fd *pfp = sdp->headfp;
2530                 while (pfp->nextfp)
2531                         pfp = pfp->nextfp;
2532                 pfp->nextfp = sfp;
2533         }
2534         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2535         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));
2536         sg_build_reserve(sfp, sg_big_buff);
2537         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp:   bufflen=%d, k_use_sg=%d\n",
2538                            sfp->reserve.bufflen, sfp->reserve.k_use_sg));
2539         return sfp;
2540 }
2541
2542 static void
2543 __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2544 {
2545         Sg_fd *fp;
2546         Sg_fd *prev_fp;
2547
2548         prev_fp = sdp->headfp;
2549         if (sfp == prev_fp)
2550                 sdp->headfp = prev_fp->nextfp;
2551         else {
2552                 while ((fp = prev_fp->nextfp)) {
2553                         if (sfp == fp) {
2554                                 prev_fp->nextfp = fp->nextfp;
2555                                 break;
2556                         }
2557                         prev_fp = fp;
2558                 }
2559         }
2560         if (sfp->reserve.bufflen > 0) {
2561                 SCSI_LOG_TIMEOUT(6,
2562                         printk("__sg_remove_sfp:    bufflen=%d, k_use_sg=%d\n",
2563                         (int) sfp->reserve.bufflen, (int) sfp->reserve.k_use_sg));
2564                 if (sfp->mmap_called)
2565                         sg_rb_correct4mmap(&sfp->reserve, 0);   /* undo correction */
2566                 sg_remove_scat(&sfp->reserve);
2567         }
2568         sfp->parentdp = NULL;
2569         SCSI_LOG_TIMEOUT(6, printk("__sg_remove_sfp:    sfp=0x%p\n", sfp));
2570         sg_page_free((char *) sfp, sizeof (Sg_fd));
2571 }
2572
2573 /* Returns 0 in normal case, 1 when detached and sdp object removed */
2574 static int
2575 sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2576 {
2577         Sg_request *srp;
2578         Sg_request *tsrp;
2579         int dirty = 0;
2580         int res = 0;
2581
2582         for (srp = sfp->headrp; srp; srp = tsrp) {
2583                 tsrp = srp->nextrp;
2584                 if (sg_srp_done(srp, sfp))
2585                         sg_finish_rem_req(srp);
2586                 else
2587                         ++dirty;
2588         }
2589         if (0 == dirty) {
2590                 unsigned long iflags;
2591
2592                 write_lock_irqsave(&sg_dev_arr_lock, iflags);
2593                 __sg_remove_sfp(sdp, sfp);
2594                 if (sdp->detached && (NULL == sdp->headfp)) {
2595                         int k, maxd;
2596
2597                         maxd = sg_dev_max;
2598                         for (k = 0; k < maxd; ++k) {
2599                                 if (sdp == sg_dev_arr[k])
2600                                         break;
2601                         }
2602                         if (k < maxd)
2603                                 sg_dev_arr[k] = NULL;
2604                         kfree((char *) sdp);
2605                         res = 1;
2606                 }
2607                 write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2608         } else {
2609                 /* MOD_INC's to inhibit unloading sg and associated adapter driver */
2610                 /* only bump the access_count if we actually succeeded in
2611                  * throwing another counter on the host module */
2612                 scsi_device_get(sdp->device);   /* XXX: retval ignored? */
2613                 sfp->closed = 1;        /* flag dirty state on this fd */
2614                 SCSI_LOG_TIMEOUT(1, printk("sg_remove_sfp: worrisome, %d writes pending\n",
2615                                   dirty));
2616         }
2617         return res;
2618 }
2619
2620 static int
2621 sg_res_in_use(Sg_fd * sfp)
2622 {
2623         const Sg_request *srp;
2624         unsigned long iflags;
2625
2626         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2627         for (srp = sfp->headrp; srp; srp = srp->nextrp)
2628                 if (srp->res_used)
2629                         break;
2630         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2631         return srp ? 1 : 0;
2632 }
2633
2634 /* If retSzp==NULL want exact size or fail */
2635 static char *
2636 sg_page_malloc(int rqSz, int lowDma, int *retSzp)
2637 {
2638         char *resp = NULL;
2639         gfp_t page_mask;
2640         int order, a_size;
2641         int resSz = rqSz;
2642
2643         if (rqSz <= 0)
2644                 return resp;
2645
2646         if (lowDma)
2647                 page_mask = GFP_ATOMIC | GFP_DMA | __GFP_NOWARN;
2648         else
2649                 page_mask = GFP_ATOMIC | __GFP_NOWARN;
2650
2651         for (order = 0, a_size = PAGE_SIZE; a_size < rqSz;
2652              order++, a_size <<= 1) ;
2653         resp = (char *) __get_free_pages(page_mask, order);
2654         while ((!resp) && order && retSzp) {
2655                 --order;
2656                 a_size >>= 1;   /* divide by 2, until PAGE_SIZE */
2657                 resp = (char *) __get_free_pages(page_mask, order);     /* try half */
2658                 resSz = a_size;
2659         }
2660         if (resp) {
2661                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2662                         memset(resp, 0, resSz);
2663                 if (retSzp)
2664                         *retSzp = resSz;
2665         }
2666         return resp;
2667 }
2668
2669 static void
2670 sg_page_free(char *buff, int size)
2671 {
2672         int order, a_size;
2673
2674         if (!buff)
2675                 return;
2676         for (order = 0, a_size = PAGE_SIZE; a_size < size;
2677              order++, a_size <<= 1) ;
2678         free_pages((unsigned long) buff, order);
2679 }
2680
2681 #ifndef MAINTENANCE_IN_CMD
2682 #define MAINTENANCE_IN_CMD 0xa3
2683 #endif
2684
2685 static unsigned char allow_ops[] = { TEST_UNIT_READY, REQUEST_SENSE,
2686         INQUIRY, READ_CAPACITY, READ_BUFFER, READ_6, READ_10, READ_12,
2687         READ_16, MODE_SENSE, MODE_SENSE_10, LOG_SENSE, REPORT_LUNS,
2688         SERVICE_ACTION_IN, RECEIVE_DIAGNOSTIC, READ_LONG, MAINTENANCE_IN_CMD
2689 };
2690
2691 static int
2692 sg_allow_access(unsigned char opcode, char dev_type)
2693 {
2694         int k;
2695
2696         if (TYPE_SCANNER == dev_type)   /* TYPE_ROM maybe burner */
2697                 return 1;
2698         for (k = 0; k < sizeof (allow_ops); ++k) {
2699                 if (opcode == allow_ops[k])
2700                         return 1;
2701         }
2702         return 0;
2703 }
2704
2705 #ifdef CONFIG_SCSI_PROC_FS
2706 static int
2707 sg_last_dev(void)
2708 {
2709         int k;
2710         unsigned long iflags;
2711
2712         read_lock_irqsave(&sg_dev_arr_lock, iflags);
2713         for (k = sg_dev_max - 1; k >= 0; --k)
2714                 if (sg_dev_arr[k] && sg_dev_arr[k]->device)
2715                         break;
2716         read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2717         return k + 1;           /* origin 1 */
2718 }
2719 #endif
2720
2721 static Sg_device *
2722 sg_get_dev(int dev)
2723 {
2724         Sg_device *sdp = NULL;
2725         unsigned long iflags;
2726
2727         if (sg_dev_arr && (dev >= 0)) {
2728                 read_lock_irqsave(&sg_dev_arr_lock, iflags);
2729                 if (dev < sg_dev_max)
2730                         sdp = sg_dev_arr[dev];
2731                 read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2732         }
2733         return sdp;
2734 }
2735
2736 #ifdef CONFIG_SCSI_PROC_FS
2737
2738 static struct proc_dir_entry *sg_proc_sgp = NULL;
2739
2740 static char sg_proc_sg_dirname[] = "scsi/sg";
2741
2742 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2743
2744 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2745 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2746                                   size_t count, loff_t *off);
2747 static struct file_operations adio_fops = {
2748         /* .owner, .read and .llseek added in sg_proc_init() */
2749         .open = sg_proc_single_open_adio,
2750         .write = sg_proc_write_adio,
2751         .release = single_release,
2752 };
2753
2754 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2755 static ssize_t sg_proc_write_dressz(struct file *filp,
2756                 const char __user *buffer, size_t count, loff_t *off);
2757 static struct file_operations dressz_fops = {
2758         .open = sg_proc_single_open_dressz,
2759         .write = sg_proc_write_dressz,
2760         .release = single_release,
2761 };
2762
2763 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2764 static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2765 static struct file_operations version_fops = {
2766         .open = sg_proc_single_open_version,
2767         .release = single_release,
2768 };
2769
2770 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2771 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2772 static struct file_operations devhdr_fops = {
2773         .open = sg_proc_single_open_devhdr,
2774         .release = single_release,
2775 };
2776
2777 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2778 static int sg_proc_open_dev(struct inode *inode, struct file *file);
2779 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2780 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2781 static void dev_seq_stop(struct seq_file *s, void *v);
2782 static struct file_operations dev_fops = {
2783         .open = sg_proc_open_dev,
2784         .release = seq_release,
2785 };
2786 static struct seq_operations dev_seq_ops = {
2787         .start = dev_seq_start,
2788         .next  = dev_seq_next,
2789         .stop  = dev_seq_stop,
2790         .show  = sg_proc_seq_show_dev,
2791 };
2792
2793 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2794 static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2795 static struct file_operations devstrs_fops = {
2796         .open = sg_proc_open_devstrs,
2797         .release = seq_release,
2798 };
2799 static struct seq_operations devstrs_seq_ops = {
2800         .start = dev_seq_start,
2801         .next  = dev_seq_next,
2802         .stop  = dev_seq_stop,
2803         .show  = sg_proc_seq_show_devstrs,
2804 };
2805
2806 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2807 static int sg_proc_open_debug(struct inode *inode, struct file *file);
2808 static struct file_operations debug_fops = {
2809         .open = sg_proc_open_debug,
2810         .release = seq_release,
2811 };
2812 static struct seq_operations debug_seq_ops = {
2813         .start = dev_seq_start,
2814         .next  = dev_seq_next,
2815         .stop  = dev_seq_stop,
2816         .show  = sg_proc_seq_show_debug,
2817 };
2818
2819
2820 struct sg_proc_leaf {
2821         const char * name;
2822         struct file_operations * fops;
2823 };
2824
2825 static struct sg_proc_leaf sg_proc_leaf_arr[] = {
2826         {"allow_dio", &adio_fops},
2827         {"debug", &debug_fops},
2828         {"def_reserved_size", &dressz_fops},
2829         {"device_hdr", &devhdr_fops},
2830         {"devices", &dev_fops},
2831         {"device_strs", &devstrs_fops},
2832         {"version", &version_fops}
2833 };
2834
2835 static int
2836 sg_proc_init(void)
2837 {
2838         int k, mask;
2839         int num_leaves =
2840             sizeof (sg_proc_leaf_arr) / sizeof (sg_proc_leaf_arr[0]);
2841         struct proc_dir_entry *pdep;
2842         struct sg_proc_leaf * leaf;
2843
2844         sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2845         if (!sg_proc_sgp)
2846                 return 1;
2847         for (k = 0; k < num_leaves; ++k) {
2848                 leaf = &sg_proc_leaf_arr[k];
2849                 mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2850                 pdep = create_proc_entry(leaf->name, mask, sg_proc_sgp);
2851                 if (pdep) {
2852                         leaf->fops->owner = THIS_MODULE,
2853                         leaf->fops->read = seq_read,
2854                         leaf->fops->llseek = seq_lseek,
2855                         pdep->proc_fops = leaf->fops;
2856                 }
2857         }
2858         return 0;
2859 }
2860
2861 static void
2862 sg_proc_cleanup(void)
2863 {
2864         int k;
2865         int num_leaves =
2866             sizeof (sg_proc_leaf_arr) / sizeof (sg_proc_leaf_arr[0]);
2867
2868         if (!sg_proc_sgp)
2869                 return;
2870         for (k = 0; k < num_leaves; ++k)
2871                 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2872         remove_proc_entry(sg_proc_sg_dirname, NULL);
2873 }
2874
2875
2876 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2877 {
2878         seq_printf(s, "%d\n", *((int *)s->private));
2879         return 0;
2880 }
2881
2882 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2883 {
2884         return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2885 }
2886
2887 static ssize_t
2888 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2889                    size_t count, loff_t *off)
2890 {
2891         int num;
2892         char buff[11];
2893
2894         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2895                 return -EACCES;
2896         num = (count < 10) ? count : 10;
2897         if (copy_from_user(buff, buffer, num))
2898                 return -EFAULT;
2899         buff[num] = '\0';
2900         sg_allow_dio = simple_strtoul(buff, NULL, 10) ? 1 : 0;
2901         return count;
2902 }
2903
2904 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2905 {
2906         return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2907 }
2908
2909 static ssize_t
2910 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2911                      size_t count, loff_t *off)
2912 {
2913         int num;
2914         unsigned long k = ULONG_MAX;
2915         char buff[11];
2916
2917         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2918                 return -EACCES;
2919         num = (count < 10) ? count : 10;
2920         if (copy_from_user(buff, buffer, num))
2921                 return -EFAULT;
2922         buff[num] = '\0';
2923         k = simple_strtoul(buff, NULL, 10);
2924         if (k <= 1048576) {     /* limit "big buff" to 1 MB */
2925                 sg_big_buff = k;
2926                 return count;
2927         }
2928         return -ERANGE;
2929 }
2930
2931 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2932 {
2933         seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2934                    sg_version_date);
2935         return 0;
2936 }
2937
2938 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2939 {
2940         return single_open(file, sg_proc_seq_show_version, NULL);
2941 }
2942
2943 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2944 {
2945         seq_printf(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\t"
2946                    "online\n");
2947         return 0;
2948 }
2949
2950 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2951 {
2952         return single_open(file, sg_proc_seq_show_devhdr, NULL);
2953 }
2954
2955 struct sg_proc_deviter {
2956         loff_t  index;
2957         size_t  max;
2958 };
2959
2960 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2961 {
2962         struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2963
2964         s->private = it;
2965         if (! it)
2966                 return NULL;
2967
2968         if (NULL == sg_dev_arr)
2969                 return NULL;
2970         it->index = *pos;
2971         it->max = sg_last_dev();
2972         if (it->index >= it->max)
2973                 return NULL;
2974         return it;
2975 }
2976
2977 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2978 {
2979         struct sg_proc_deviter * it = s->private;
2980
2981         *pos = ++it->index;
2982         return (it->index < it->max) ? it : NULL;
2983 }
2984
2985 static void dev_seq_stop(struct seq_file *s, void *v)
2986 {
2987         kfree(s->private);
2988 }
2989
2990 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2991 {
2992         return seq_open(file, &dev_seq_ops);
2993 }
2994
2995 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2996 {
2997         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2998         Sg_device *sdp;
2999         struct scsi_device *scsidp;
3000
3001         sdp = it ? sg_get_dev(it->index) : NULL;
3002         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
3003                 seq_printf(s, "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n",
3004                               scsidp->host->host_no, scsidp->channel,
3005                               scsidp->id, scsidp->lun, (int) scsidp->type,
3006                               1,
3007                               (int) scsidp->queue_depth,
3008                               (int) scsidp->device_busy,
3009                               (int) scsi_device_online(scsidp));
3010         else
3011                 seq_printf(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
3012         return 0;
3013 }
3014
3015 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
3016 {
3017         return seq_open(file, &devstrs_seq_ops);
3018 }
3019
3020 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
3021 {
3022         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
3023         Sg_device *sdp;
3024         struct scsi_device *scsidp;
3025
3026         sdp = it ? sg_get_dev(it->index) : NULL;
3027         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
3028                 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
3029                            scsidp->vendor, scsidp->model, scsidp->rev);
3030         else
3031                 seq_printf(s, "<no active device>\n");
3032         return 0;
3033 }
3034
3035 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
3036 {
3037         int k, m, new_interface, blen, usg;
3038         Sg_request *srp;
3039         Sg_fd *fp;
3040         const sg_io_hdr_t *hp;
3041         const char * cp;
3042         unsigned int ms;
3043
3044         for (k = 0; (fp = sg_get_nth_sfp(sdp, k)); ++k) {
3045                 seq_printf(s, "   FD(%d): timeout=%dms bufflen=%d "
3046                            "(res)sgat=%d low_dma=%d\n", k + 1,
3047                            jiffies_to_msecs(fp->timeout),
3048                            fp->reserve.bufflen,
3049                            (int) fp->reserve.k_use_sg,
3050                            (int) fp->low_dma);
3051                 seq_printf(s, "   cmd_q=%d f_packid=%d k_orphan=%d closed=%d\n",
3052                            (int) fp->cmd_q, (int) fp->force_packid,
3053                            (int) fp->keep_orphan, (int) fp->closed);
3054                 for (m = 0; (srp = sg_get_nth_request(fp, m)); ++m) {
3055                         hp = &srp->header;
3056                         new_interface = (hp->interface_id == '\0') ? 0 : 1;
3057                         if (srp->res_used) {
3058                                 if (new_interface &&
3059                                     (SG_FLAG_MMAP_IO & hp->flags))
3060                                         cp = "     mmap>> ";
3061                                 else
3062                                         cp = "     rb>> ";
3063                         } else {
3064                                 if (SG_INFO_DIRECT_IO_MASK & hp->info)
3065                                         cp = "     dio>> ";
3066                                 else
3067                                         cp = "     ";
3068                         }
3069                         seq_printf(s, cp);
3070                         blen = srp->my_cmdp ?
3071                                 srp->my_cmdp->sr_bufflen : srp->data.bufflen;
3072                         usg = srp->my_cmdp ?
3073                                 srp->my_cmdp->sr_use_sg : srp->data.k_use_sg;
3074                         seq_printf(s, srp->done ?
3075                                    ((1 == srp->done) ?  "rcv:" : "fin:")
3076                                    : (srp->my_cmdp ? "act:" : "prior:"));
3077                         seq_printf(s, " id=%d blen=%d",
3078                                    srp->header.pack_id, blen);
3079                         if (srp->done)
3080                                 seq_printf(s, " dur=%d", hp->duration);
3081                         else {
3082                                 ms = jiffies_to_msecs(jiffies);
3083                                 seq_printf(s, " t_o/elap=%d/%d",
3084                                         (new_interface ? hp->timeout :
3085                                                   jiffies_to_msecs(fp->timeout)),
3086                                         (ms > hp->duration ? ms - hp->duration : 0));
3087                         }
3088                         seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
3089                                    (int) srp->data.cmd_opcode);
3090                 }
3091                 if (0 == m)
3092                         seq_printf(s, "     No requests active\n");
3093         }
3094 }
3095
3096 static int sg_proc_open_debug(struct inode *inode, struct file *file)
3097 {
3098         return seq_open(file, &debug_seq_ops);
3099 }
3100
3101 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
3102 {
3103         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
3104         Sg_device *sdp;
3105
3106         if (it && (0 == it->index)) {
3107                 seq_printf(s, "dev_max(currently)=%d max_active_device=%d "
3108                            "(origin 1)\n", sg_dev_max, (int)it->max);
3109                 seq_printf(s, " def_reserved_size=%d\n", sg_big_buff);
3110         }
3111         sdp = it ? sg_get_dev(it->index) : NULL;
3112         if (sdp) {
3113                 struct scsi_device *scsidp = sdp->device;
3114
3115                 if (NULL == scsidp) {
3116                         seq_printf(s, "device %d detached ??\n",
3117                                    (int)it->index);
3118                         return 0;
3119                 }
3120
3121                 if (sg_get_nth_sfp(sdp, 0)) {
3122                         seq_printf(s, " >>> device=%s ",
3123                                 sdp->disk->disk_name);
3124                         if (sdp->detached)
3125                                 seq_printf(s, "detached pending close ");
3126                         else
3127                                 seq_printf
3128                                     (s, "scsi%d chan=%d id=%d lun=%d   em=%d",
3129                                      scsidp->host->host_no,
3130                                      scsidp->channel, scsidp->id,
3131                                      scsidp->lun,
3132                                      scsidp->host->hostt->emulated);
3133                         seq_printf(s, " sg_tablesize=%d excl=%d\n",
3134                                    sdp->sg_tablesize, sdp->exclude);
3135                 }
3136                 sg_proc_debug_helper(s, sdp);
3137         }
3138         return 0;
3139 }
3140
3141 #endif                          /* CONFIG_SCSI_PROC_FS */
3142
3143 module_init(init_sg);
3144 module_exit(exit_sg);
3145 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);