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   1 /*
   2  *  History:
   3  *  Started: Aug 9 by Lawrence Foard (entropy@world.std.com),
   4  *           to allow user process control of SCSI devices.
   5  *  Development Sponsored by Killy Corp. NY NY
   6  *
   7  * Original driver (sg.c):
   8  *        Copyright (C) 1992 Lawrence Foard
   9  * Version 2 and 3 extensions to driver:
  10  *        Copyright (C) 1998 - 2005 Douglas Gilbert
  11  *
  12  *  Modified  19-JAN-1998  Richard Gooch <rgooch@atnf.csiro.au>  Devfs support
  13  *
  14  * This program is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2, or (at your option)
  17  * any later version.
  18  *
  19  */
  20
  21 static int sg_version_num = 30534;      /* 2 digits for each component */
  22 #define SG_VERSION_STR "3.5.34"
  23
  24 /*
  25  *  D. P. Gilbert (dgilbert@interlog.com, dougg@triode.net.au), notes:
  26  *      - scsi logging is available via SCSI_LOG_TIMEOUT macros. First
  27  *        the kernel/module needs to be built with CONFIG_SCSI_LOGGING
  28  *        (otherwise the macros compile to empty statements).
  29  *
  30  */
  31 #include <linux/module.h>
  32
  33 #include <linux/fs.h>
  34 #include <linux/kernel.h>
  35 #include <linux/sched.h>
  36 #include <linux/string.h>
  37 #include <linux/mm.h>
  38 #include <linux/errno.h>
  39 #include <linux/mtio.h>
  40 #include <linux/ioctl.h>
  41 #include <linux/fcntl.h>
  42 #include <linux/init.h>
  43 #include <linux/poll.h>
  44 #include <linux/moduleparam.h>
  45 #include <linux/cdev.h>
  46 #include <linux/idr.h>
  47 #include <linux/seq_file.h>
  48 #include <linux/blkdev.h>
  49 #include <linux/delay.h>
  50 #include <linux/blktrace_api.h>
  51 #include <linux/smp_lock.h>
  52
  53 #include "scsi.h"
  54 #include <scsi/scsi_dbg.h>
  55 #include <scsi/scsi_host.h>
  56 #include <scsi/scsi_driver.h>
  57 #include <scsi/scsi_ioctl.h>
  58 #include <scsi/sg.h>
  59
  60 #include "scsi_logging.h"
  61
  62 #ifdef CONFIG_SCSI_PROC_FS
  63 #include <linux/proc_fs.h>
  64 static char *sg_version_date = "20061027";
  65
  66 static int sg_proc_init(void);
  67 static void sg_proc_cleanup(void);
  68 #endif
  69
  70 #define SG_ALLOW_DIO_DEF 0
  71
  72 #define SG_MAX_DEVS 32768
  73
  74 /*
  75  * Suppose you want to calculate the formula muldiv(x,m,d)=int(x * m / d)
  76  * Then when using 32 bit integers x * m may overflow during the calculation.
  77  * Replacing muldiv(x) by muldiv(x)=((x % d) * m) / d + int(x / d) * m
  78  * calculates the same, but prevents the overflow when both m and d
  79  * are "small" numbers (like HZ and USER_HZ).
  80  * Of course an overflow is inavoidable if the result of muldiv doesn't fit
  81  * in 32 bits.
  82  */
  83 #define MULDIV(X,MUL,DIV) ((((X % DIV) * MUL) / DIV) + ((X / DIV) * MUL))
  84
  85 #define SG_DEFAULT_TIMEOUT MULDIV(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
  86
  87 int sg_big_buff = SG_DEF_RESERVED_SIZE;
  88 /* N.B. This variable is readable and writeable via
  89    /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
  90    of this size (or less if there is not enough memory) will be reserved
  91    for use by this file descriptor. [Deprecated usage: this variable is also
  92    readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
  93    the kernel (i.e. it is not a module).] */
  94 static int def_reserved_size = -1;      /* picks up init parameter */
  95 static int sg_allow_dio = SG_ALLOW_DIO_DEF;
  96
  97 static int scatter_elem_sz = SG_SCATTER_SZ;
  98 static int scatter_elem_sz_prev = SG_SCATTER_SZ;
  99
 100 #define SG_SECTOR_SZ 512
 101 #define SG_SECTOR_MSK (SG_SECTOR_SZ - 1)
 102
 103 static int sg_add(struct device *, struct class_interface *);
 104 static void sg_remove(struct device *, struct class_interface *);
 105
 106 static DEFINE_IDR(sg_index_idr);
 107 static DEFINE_RWLOCK(sg_index_lock);    /* Also used to lock
 108                                                            file descriptor list for device */
 109
 110 static struct class_interface sg_interface = {
 111         .add_dev        = sg_add,
 112         .remove_dev     = sg_remove,
 113 };
 114
 115 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
 116         unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
 117         unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */
 118         unsigned bufflen;       /* Size of (aggregate) data buffer */
 119         unsigned b_malloc_len;  /* actual len malloc'ed in buffer */
 120         struct page **pages;
 121         int page_order;
 122         char dio_in_use;        /* 0->indirect IO (or mmap), 1->dio */
 123         unsigned char cmd_opcode; /* first byte of command */
 124 } Sg_scatter_hold;
 125
 126 struct sg_device;               /* forward declarations */
 127 struct sg_fd;
 128
 129 typedef struct sg_request {     /* SG_MAX_QUEUE requests outstanding per file */
 130         struct sg_request *nextrp;      /* NULL -> tail request (slist) */
 131         struct sg_fd *parentfp; /* NULL -> not in use */
 132         Sg_scatter_hold data;   /* hold buffer, perhaps scatter list */
 133         sg_io_hdr_t header;     /* scsi command+info, see <scsi/sg.h> */
 134         unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
 135         char res_used;          /* 1 -> using reserve buffer, 0 -> not ... */
 136         char orphan;            /* 1 -> drop on sight, 0 -> normal */
 137         char sg_io_owned;       /* 1 -> packet belongs to SG_IO */
 138         volatile char done;     /* 0->before bh, 1->before read, 2->read */
 139         struct request *rq;
 140         struct bio *bio;
 141 } 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         u32 index;              /* device index number */
 169         Sg_fd *headfp;          /* first open fd belonging to this device */
 170         volatile char detached; /* 0->attached, 1->detached pending removal */
 171         volatile char exclude;  /* opened for exclusive access */
 172         char sgdebug;           /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
 173         struct gendisk *disk;
 174         struct cdev * cdev;     /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
 175 } Sg_device;
 176
 177 static int sg_fasync(int fd, struct file *filp, int mode);
 178 /* tasklet or soft irq callback */
 179 static void sg_rq_end_io(struct request *rq, int uptodate);
 180 static int sg_start_req(Sg_request *srp, unsigned char *cmd);
 181 static void sg_finish_rem_req(Sg_request * srp);
 182 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
 183 static int sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp,
 184                          int tablesize);
 185 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
 186                            Sg_request * srp);
 187 static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
 188                         const char __user *buf, size_t count, int blocking,
 189                         int read_only, Sg_request **o_srp);
 190 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
 191                            unsigned char *cmnd, int timeout, int blocking);
 192 static int sg_write_xfer(Sg_request * srp);
 193 static int sg_read_xfer(Sg_request * srp);
 194 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
 195 static void sg_remove_scat(Sg_scatter_hold * schp);
 196 static void sg_build_reserve(Sg_fd * sfp, int req_size);
 197 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
 198 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
 199 static Sg_fd *sg_add_sfp(Sg_device * sdp, int dev);
 200 static int sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
 201 static void __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
 202 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
 203 static Sg_request *sg_add_request(Sg_fd * sfp);
 204 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
 205 static int sg_res_in_use(Sg_fd * sfp);
 206 static int sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len);
 207 static Sg_device *sg_get_dev(int dev);
 208 #ifdef CONFIG_SCSI_PROC_FS
 209 static int sg_last_dev(void);
 210 #endif
 211
 212 #define SZ_SG_HEADER sizeof(struct sg_header)
 213 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
 214 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
 215 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
 216
 217 static int sg_allow_access(struct file *filp, unsigned char *cmd)
 218 {
 219         struct sg_fd *sfp = (struct sg_fd *)filp->private_data;
 220         struct request_queue *q = sfp->parentdp->device->request_queue;
 221
 222         if (sfp->parentdp->device->type == TYPE_SCANNER)
 223                 return 0;
 224
 225         return blk_verify_command(&q->cmd_filter,
 226                                   cmd, filp->f_mode & FMODE_WRITE);
 227 }
 228
 229 static int
 230 sg_open(struct inode *inode, struct file *filp)
 231 {
 232         int dev = iminor(inode);
 233         int flags = filp->f_flags;
 234         struct request_queue *q;
 235         Sg_device *sdp;
 236         Sg_fd *sfp;
 237         int res;
 238         int retval;
 239
 240         lock_kernel();
 241         nonseekable_open(inode, filp);
 242         SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags));
 243         sdp = sg_get_dev(dev);
 244         if ((!sdp) || (!sdp->device)) {
 245                 unlock_kernel();
 246                 return -ENXIO;
 247         }
 248         if (sdp->detached) {
 249                 unlock_kernel();
 250                 return -ENODEV;
 251         }
 252
 253         /* This driver's module count bumped by fops_get in <linux/fs.h> */
 254         /* Prevent the device driver from vanishing while we sleep */
 255         retval = scsi_device_get(sdp->device);
 256         if (retval) {
 257                 unlock_kernel();
 258                 return retval;
 259         }
 260
 261         if (!((flags & O_NONBLOCK) ||
 262               scsi_block_when_processing_errors(sdp->device))) {
 263                 retval = -ENXIO;
 264                 /* we are in error recovery for this device */
 265                 goto error_out;
 266         }
 267
 268         if (flags & O_EXCL) {
 269                 if (O_RDONLY == (flags & O_ACCMODE)) {
 270                         retval = -EPERM; /* Can't lock it with read only access */
 271                         goto error_out;
 272                 }
 273                 if (sdp->headfp && (flags & O_NONBLOCK)) {
 274                         retval = -EBUSY;
 275                         goto error_out;
 276                 }
 277                 res = 0;
 278                 __wait_event_interruptible(sdp->o_excl_wait,
 279                         ((sdp->headfp || sdp->exclude) ? 0 : (sdp->exclude = 1)), res);
 280                 if (res) {
 281                         retval = res;   /* -ERESTARTSYS because signal hit process */
 282                         goto error_out;
 283                 }
 284         } else if (sdp->exclude) {      /* some other fd has an exclusive lock on dev */
 285                 if (flags & O_NONBLOCK) {
 286                         retval = -EBUSY;
 287                         goto error_out;
 288                 }
 289                 res = 0;
 290                 __wait_event_interruptible(sdp->o_excl_wait, (!sdp->exclude),
 291                                            res);
 292                 if (res) {
 293                         retval = res;   /* -ERESTARTSYS because signal hit process */
 294                         goto error_out;
 295                 }
 296         }
 297         if (sdp->detached) {
 298                 retval = -ENODEV;
 299                 goto error_out;
 300         }
 301         if (!sdp->headfp) {     /* no existing opens on this device */
 302                 sdp->sgdebug = 0;
 303                 q = sdp->device->request_queue;
 304                 sdp->sg_tablesize = min(q->max_hw_segments,
 305                                         q->max_phys_segments);
 306         }
 307         if ((sfp = sg_add_sfp(sdp, dev)))
 308                 filp->private_data = sfp;
 309         else {
 310                 if (flags & O_EXCL)
 311                         sdp->exclude = 0;       /* undo if error */
 312                 retval = -ENOMEM;
 313                 goto error_out;
 314         }
 315         unlock_kernel();
 316         return 0;
 317
 318       error_out:
 319         scsi_device_put(sdp->device);
 320         unlock_kernel();
 321         return retval;
 322 }
 323
 324 /* Following function was formerly called 'sg_close' */
 325 static int
 326 sg_release(struct inode *inode, struct file *filp)
 327 {
 328         Sg_device *sdp;
 329         Sg_fd *sfp;
 330
 331         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 332                 return -ENXIO;
 333         SCSI_LOG_TIMEOUT(3, printk("sg_release: %s\n", sdp->disk->disk_name));
 334         sg_fasync(-1, filp, 0); /* remove filp from async notification list */
 335         if (0 == sg_remove_sfp(sdp, sfp)) {     /* Returns 1 when sdp gone */
 336                 if (!sdp->detached) {
 337                         scsi_device_put(sdp->device);
 338                 }
 339                 sdp->exclude = 0;
 340                 wake_up_interruptible(&sdp->o_excl_wait);
 341         }
 342         return 0;
 343 }
 344
 345 static ssize_t
 346 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
 347 {
 348         Sg_device *sdp;
 349         Sg_fd *sfp;
 350         Sg_request *srp;
 351         int req_pack_id = -1;
 352         sg_io_hdr_t *hp;
 353         struct sg_header *old_hdr = NULL;
 354         int retval = 0;
 355
 356         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 357                 return -ENXIO;
 358         SCSI_LOG_TIMEOUT(3, printk("sg_read: %s, count=%d\n",
 359                                    sdp->disk->disk_name, (int) count));
 360
 361         if (!access_ok(VERIFY_WRITE, buf, count))
 362                 return -EFAULT;
 363         if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
 364                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 365                 if (!old_hdr)
 366                         return -ENOMEM;
 367                 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
 368                         retval = -EFAULT;
 369                         goto free_old_hdr;
 370                 }
 371                 if (old_hdr->reply_len < 0) {
 372                         if (count >= SZ_SG_IO_HDR) {
 373                                 sg_io_hdr_t *new_hdr;
 374                                 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
 375                                 if (!new_hdr) {
 376                                         retval = -ENOMEM;
 377                                         goto free_old_hdr;
 378                                 }
 379                                 retval =__copy_from_user
 380                                     (new_hdr, buf, SZ_SG_IO_HDR);
 381                                 req_pack_id = new_hdr->pack_id;
 382                                 kfree(new_hdr);
 383                                 if (retval) {
 384                                         retval = -EFAULT;
 385                                         goto free_old_hdr;
 386                                 }
 387                         }
 388                 } else
 389                         req_pack_id = old_hdr->pack_id;
 390         }
 391         srp = sg_get_rq_mark(sfp, req_pack_id);
 392         if (!srp) {             /* now wait on packet to arrive */
 393                 if (sdp->detached) {
 394                         retval = -ENODEV;
 395                         goto free_old_hdr;
 396                 }
 397                 if (filp->f_flags & O_NONBLOCK) {
 398                         retval = -EAGAIN;
 399                         goto free_old_hdr;
 400                 }
 401                 while (1) {
 402                         retval = 0; /* following macro beats race condition */
 403                         __wait_event_interruptible(sfp->read_wait,
 404                                 (sdp->detached ||
 405                                 (srp = sg_get_rq_mark(sfp, req_pack_id))),
 406                                 retval);
 407                         if (sdp->detached) {
 408                                 retval = -ENODEV;
 409                                 goto free_old_hdr;
 410                         }
 411                         if (0 == retval)
 412                                 break;
 413
 414                         /* -ERESTARTSYS as signal hit process */
 415                         goto free_old_hdr;
 416                 }
 417         }
 418         if (srp->header.interface_id != '\0') {
 419                 retval = sg_new_read(sfp, buf, count, srp);
 420                 goto free_old_hdr;
 421         }
 422
 423         hp = &srp->header;
 424         if (old_hdr == NULL) {
 425                 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 426                 if (! old_hdr) {
 427                         retval = -ENOMEM;
 428                         goto free_old_hdr;
 429                 }
 430         }
 431         memset(old_hdr, 0, SZ_SG_HEADER);
 432         old_hdr->reply_len = (int) hp->timeout;
 433         old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
 434         old_hdr->pack_id = hp->pack_id;
 435         old_hdr->twelve_byte =
 436             ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
 437         old_hdr->target_status = hp->masked_status;
 438         old_hdr->host_status = hp->host_status;
 439         old_hdr->driver_status = hp->driver_status;
 440         if ((CHECK_CONDITION & hp->masked_status) ||
 441             (DRIVER_SENSE & hp->driver_status))
 442                 memcpy(old_hdr->sense_buffer, srp->sense_b,
 443                        sizeof (old_hdr->sense_buffer));
 444         switch (hp->host_status) {
 445         /* This setup of 'result' is for backward compatibility and is best
 446            ignored by the user who should use target, host + driver status */
 447         case DID_OK:
 448         case DID_PASSTHROUGH:
 449         case DID_SOFT_ERROR:
 450                 old_hdr->result = 0;
 451                 break;
 452         case DID_NO_CONNECT:
 453         case DID_BUS_BUSY:
 454         case DID_TIME_OUT:
 455                 old_hdr->result = EBUSY;
 456                 break;
 457         case DID_BAD_TARGET:
 458         case DID_ABORT:
 459         case DID_PARITY:
 460         case DID_RESET:
 461         case DID_BAD_INTR:
 462                 old_hdr->result = EIO;
 463                 break;
 464         case DID_ERROR:
 465                 old_hdr->result = (srp->sense_b[0] == 0 &&
 466                                   hp->masked_status == GOOD) ? 0 : EIO;
 467                 break;
 468         default:
 469                 old_hdr->result = EIO;
 470                 break;
 471         }
 472
 473         /* Now copy the result back to the user buffer.  */
 474         if (count >= SZ_SG_HEADER) {
 475                 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
 476                         retval = -EFAULT;
 477                         goto free_old_hdr;
 478                 }
 479                 buf += SZ_SG_HEADER;
 480                 if (count > old_hdr->reply_len)
 481                         count = old_hdr->reply_len;
 482                 if (count > SZ_SG_HEADER) {
 483                         if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
 484                                 retval = -EFAULT;
 485                                 goto free_old_hdr;
 486                         }
 487                 }
 488         } else
 489                 count = (old_hdr->result == 0) ? 0 : -EIO;
 490         sg_finish_rem_req(srp);
 491         retval = count;
 492 free_old_hdr:
 493         kfree(old_hdr);
 494         return retval;
 495 }
 496
 497 static ssize_t
 498 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
 499 {
 500         sg_io_hdr_t *hp = &srp->header;
 501         int err = 0;
 502         int len;
 503
 504         if (count < SZ_SG_IO_HDR) {
 505                 err = -EINVAL;
 506                 goto err_out;
 507         }
 508         hp->sb_len_wr = 0;
 509         if ((hp->mx_sb_len > 0) && hp->sbp) {
 510                 if ((CHECK_CONDITION & hp->masked_status) ||
 511                     (DRIVER_SENSE & hp->driver_status)) {
 512                         int sb_len = SCSI_SENSE_BUFFERSIZE;
 513                         sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
 514                         len = 8 + (int) srp->sense_b[7];        /* Additional sense length field */
 515                         len = (len > sb_len) ? sb_len : len;
 516                         if (copy_to_user(hp->sbp, srp->sense_b, len)) {
 517                                 err = -EFAULT;
 518                                 goto err_out;
 519                         }
 520                         hp->sb_len_wr = len;
 521                 }
 522         }
 523         if (hp->masked_status || hp->host_status || hp->driver_status)
 524                 hp->info |= SG_INFO_CHECK;
 525         if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
 526                 err = -EFAULT;
 527                 goto err_out;
 528         }
 529         err = sg_read_xfer(srp);
 530       err_out:
 531         sg_finish_rem_req(srp);
 532         return (0 == err) ? count : err;
 533 }
 534
 535 static ssize_t
 536 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
 537 {
 538         int mxsize, cmd_size, k;
 539         int input_size, blocking;
 540         unsigned char opcode;
 541         Sg_device *sdp;
 542         Sg_fd *sfp;
 543         Sg_request *srp;
 544         struct sg_header old_hdr;
 545         sg_io_hdr_t *hp;
 546         unsigned char cmnd[MAX_COMMAND_SIZE];
 547
 548         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 549                 return -ENXIO;
 550         SCSI_LOG_TIMEOUT(3, printk("sg_write: %s, count=%d\n",
 551                                    sdp->disk->disk_name, (int) count));
 552         if (sdp->detached)
 553                 return -ENODEV;
 554         if (!((filp->f_flags & O_NONBLOCK) ||
 555               scsi_block_when_processing_errors(sdp->device)))
 556                 return -ENXIO;
 557
 558         if (!access_ok(VERIFY_READ, buf, count))
 559                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 560         if (count < SZ_SG_HEADER)
 561                 return -EIO;
 562         if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
 563                 return -EFAULT;
 564         blocking = !(filp->f_flags & O_NONBLOCK);
 565         if (old_hdr.reply_len < 0)
 566                 return sg_new_write(sfp, filp, buf, count, blocking, 0, NULL);
 567         if (count < (SZ_SG_HEADER + 6))
 568                 return -EIO;    /* The minimum scsi command length is 6 bytes. */
 569
 570         if (!(srp = sg_add_request(sfp))) {
 571                 SCSI_LOG_TIMEOUT(1, printk("sg_write: queue full\n"));
 572                 return -EDOM;
 573         }
 574         buf += SZ_SG_HEADER;
 575         __get_user(opcode, buf);
 576         if (sfp->next_cmd_len > 0) {
 577                 if (sfp->next_cmd_len > MAX_COMMAND_SIZE) {
 578                         SCSI_LOG_TIMEOUT(1, printk("sg_write: command length too long\n"));
 579                         sfp->next_cmd_len = 0;
 580                         sg_remove_request(sfp, srp);
 581                         return -EIO;
 582                 }
 583                 cmd_size = sfp->next_cmd_len;
 584                 sfp->next_cmd_len = 0;  /* reset so only this write() effected */
 585         } else {
 586                 cmd_size = COMMAND_SIZE(opcode);        /* based on SCSI command group */
 587                 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
 588                         cmd_size = 12;
 589         }
 590         SCSI_LOG_TIMEOUT(4, printk(
 591                 "sg_write:   scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
 592 /* Determine buffer size.  */
 593         input_size = count - cmd_size;
 594         mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
 595         mxsize -= SZ_SG_HEADER;
 596         input_size -= SZ_SG_HEADER;
 597         if (input_size < 0) {
 598                 sg_remove_request(sfp, srp);
 599                 return -EIO;    /* User did not pass enough bytes for this command. */
 600         }
 601         hp = &srp->header;
 602         hp->interface_id = '\0';        /* indicator of old interface tunnelled */
 603         hp->cmd_len = (unsigned char) cmd_size;
 604         hp->iovec_count = 0;
 605         hp->mx_sb_len = 0;
 606         if (input_size > 0)
 607                 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
 608                     SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
 609         else
 610                 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
 611         hp->dxfer_len = mxsize;
 612         if (hp->dxfer_direction == SG_DXFER_TO_DEV)
 613                 hp->dxferp = (char __user *)buf + cmd_size;
 614         else
 615                 hp->dxferp = NULL;
 616         hp->sbp = NULL;
 617         hp->timeout = old_hdr.reply_len;        /* structure abuse ... */
 618         hp->flags = input_size; /* structure abuse ... */
 619         hp->pack_id = old_hdr.pack_id;
 620         hp->usr_ptr = NULL;
 621         if (__copy_from_user(cmnd, buf, cmd_size))
 622                 return -EFAULT;
 623         /*
 624          * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
 625          * but is is possible that the app intended SG_DXFER_TO_DEV, because there
 626          * is a non-zero input_size, so emit a warning.
 627          */
 628         if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
 629                 static char cmd[TASK_COMM_LEN];
 630                 if (strcmp(current->comm, cmd) && printk_ratelimit()) {
 631                         printk(KERN_WARNING
 632                                "sg_write: data in/out %d/%d bytes for SCSI command 0x%x--"
 633                                "guessing data in;\n" KERN_WARNING "   "
 634                                "program %s not setting count and/or reply_len properly\n",
 635                                old_hdr.reply_len - (int)SZ_SG_HEADER,
 636                                input_size, (unsigned int) cmnd[0],
 637                                current->comm);
 638                         strcpy(cmd, current->comm);
 639                 }
 640         }
 641         k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
 642         return (k < 0) ? k : count;
 643 }
 644
 645 static ssize_t
 646 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
 647                  size_t count, int blocking, int read_only,
 648                  Sg_request **o_srp)
 649 {
 650         int k;
 651         Sg_request *srp;
 652         sg_io_hdr_t *hp;
 653         unsigned char cmnd[MAX_COMMAND_SIZE];
 654         int timeout;
 655         unsigned long ul_timeout;
 656
 657         if (count < SZ_SG_IO_HDR)
 658                 return -EINVAL;
 659         if (!access_ok(VERIFY_READ, buf, count))
 660                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 661
 662         sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
 663         if (!(srp = sg_add_request(sfp))) {
 664                 SCSI_LOG_TIMEOUT(1, printk("sg_new_write: queue full\n"));
 665                 return -EDOM;
 666         }
 667         hp = &srp->header;
 668         if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
 669                 sg_remove_request(sfp, srp);
 670                 return -EFAULT;
 671         }
 672         if (hp->interface_id != 'S') {
 673                 sg_remove_request(sfp, srp);
 674                 return -ENOSYS;
 675         }
 676         if (hp->flags & SG_FLAG_MMAP_IO) {
 677                 if (hp->dxfer_len > sfp->reserve.bufflen) {
 678                         sg_remove_request(sfp, srp);
 679                         return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
 680                 }
 681                 if (hp->flags & SG_FLAG_DIRECT_IO) {
 682                         sg_remove_request(sfp, srp);
 683                         return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
 684                 }
 685                 if (sg_res_in_use(sfp)) {
 686                         sg_remove_request(sfp, srp);
 687                         return -EBUSY;  /* reserve buffer already being used */
 688                 }
 689         }
 690         ul_timeout = msecs_to_jiffies(srp->header.timeout);
 691         timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
 692         if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
 693                 sg_remove_request(sfp, srp);
 694                 return -EMSGSIZE;
 695         }
 696         if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
 697                 sg_remove_request(sfp, srp);
 698                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 699         }
 700         if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
 701                 sg_remove_request(sfp, srp);
 702                 return -EFAULT;
 703         }
 704         if (read_only && sg_allow_access(file, cmnd)) {
 705                 sg_remove_request(sfp, srp);
 706                 return -EPERM;
 707         }
 708         k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
 709         if (k < 0)
 710                 return k;
 711         if (o_srp)
 712                 *o_srp = srp;
 713         return count;
 714 }
 715
 716 static int
 717 sg_common_write(Sg_fd * sfp, Sg_request * srp,
 718                 unsigned char *cmnd, int timeout, int blocking)
 719 {
 720         int k, data_dir;
 721         Sg_device *sdp = sfp->parentdp;
 722         sg_io_hdr_t *hp = &srp->header;
 723
 724         srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
 725         hp->status = 0;
 726         hp->masked_status = 0;
 727         hp->msg_status = 0;
 728         hp->info = 0;
 729         hp->host_status = 0;
 730         hp->driver_status = 0;
 731         hp->resid = 0;
 732         SCSI_LOG_TIMEOUT(4, printk("sg_common_write:  scsi opcode=0x%02x, cmd_size=%d\n",
 733                           (int) cmnd[0], (int) hp->cmd_len));
 734
 735         k = sg_start_req(srp, cmnd);
 736         if (k) {
 737                 SCSI_LOG_TIMEOUT(1, printk("sg_common_write: start_req err=%d\n", k));
 738                 sg_finish_rem_req(srp);
 739                 return k;       /* probably out of space --> ENOMEM */
 740         }
 741         if ((k = sg_write_xfer(srp))) {
 742                 SCSI_LOG_TIMEOUT(1, printk("sg_common_write: write_xfer, bad address\n"));
 743                 sg_finish_rem_req(srp);
 744                 return k;
 745         }
 746         if (sdp->detached) {
 747                 sg_finish_rem_req(srp);
 748                 return -ENODEV;
 749         }
 750
 751         switch (hp->dxfer_direction) {
 752         case SG_DXFER_TO_FROM_DEV:
 753         case SG_DXFER_FROM_DEV:
 754                 data_dir = DMA_FROM_DEVICE;
 755                 break;
 756         case SG_DXFER_TO_DEV:
 757                 data_dir = DMA_TO_DEVICE;
 758                 break;
 759         case SG_DXFER_UNKNOWN:
 760                 data_dir = DMA_BIDIRECTIONAL;
 761                 break;
 762         default:
 763                 data_dir = DMA_NONE;
 764                 break;
 765         }
 766         hp->duration = jiffies_to_msecs(jiffies);
 767
 768         srp->rq->timeout = timeout;
 769         blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk,
 770                               srp->rq, 1, sg_rq_end_io);
 771         return 0;
 772 }
 773
 774 static int
 775 sg_srp_done(Sg_request *srp, Sg_fd *sfp)
 776 {
 777         unsigned long iflags;
 778         int done;
 779
 780         read_lock_irqsave(&sfp->rq_list_lock, iflags);
 781         done = srp->done;
 782         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 783         return done;
 784 }
 785
 786 static int
 787 sg_ioctl(struct inode *inode, struct file *filp,
 788          unsigned int cmd_in, unsigned long arg)
 789 {
 790         void __user *p = (void __user *)arg;
 791         int __user *ip = p;
 792         int result, val, read_only;
 793         Sg_device *sdp;
 794         Sg_fd *sfp;
 795         Sg_request *srp;
 796         unsigned long iflags;
 797
 798         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 799                 return -ENXIO;
 800
 801         SCSI_LOG_TIMEOUT(3, printk("sg_ioctl: %s, cmd=0x%x\n",
 802                                    sdp->disk->disk_name, (int) cmd_in));
 803         read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
 804
 805         switch (cmd_in) {
 806         case SG_IO:
 807                 {
 808                         int blocking = 1;       /* ignore O_NONBLOCK flag */
 809
 810                         if (sdp->detached)
 811                                 return -ENODEV;
 812                         if (!scsi_block_when_processing_errors(sdp->device))
 813                                 return -ENXIO;
 814                         if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
 815                                 return -EFAULT;
 816                         result =
 817                             sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
 818                                          blocking, read_only, &srp);
 819                         if (result < 0)
 820                                 return result;
 821                         srp->sg_io_owned = 1;
 822                         while (1) {
 823                                 result = 0;     /* following macro to beat race condition */
 824                                 __wait_event_interruptible(sfp->read_wait,
 825                                         (sdp->detached || sfp->closed || sg_srp_done(srp, sfp)),
 826                                                            result);
 827                                 if (sdp->detached)
 828                                         return -ENODEV;
 829                                 if (sfp->closed)
 830                                         return 0;       /* request packet dropped already */
 831                                 if (0 == result)
 832                                         break;
 833                                 srp->orphan = 1;
 834                                 return result;  /* -ERESTARTSYS because signal hit process */
 835                         }
 836                         write_lock_irqsave(&sfp->rq_list_lock, iflags);
 837                         srp->done = 2;
 838                         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 839                         result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
 840                         return (result < 0) ? result : 0;
 841                 }
 842         case SG_SET_TIMEOUT:
 843                 result = get_user(val, ip);
 844                 if (result)
 845                         return result;
 846                 if (val < 0)
 847                         return -EIO;
 848                 if (val >= MULDIV (INT_MAX, USER_HZ, HZ))
 849                     val = MULDIV (INT_MAX, USER_HZ, HZ);
 850                 sfp->timeout_user = val;
 851                 sfp->timeout = MULDIV (val, HZ, USER_HZ);
 852
 853                 return 0;
 854         case SG_GET_TIMEOUT:    /* N.B. User receives timeout as return value */
 855                                 /* strange ..., for backward compatibility */
 856                 return sfp->timeout_user;
 857         case SG_SET_FORCE_LOW_DMA:
 858                 result = get_user(val, ip);
 859                 if (result)
 860                         return result;
 861                 if (val) {
 862                         sfp->low_dma = 1;
 863                         if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
 864                                 val = (int) sfp->reserve.bufflen;
 865                                 sg_remove_scat(&sfp->reserve);
 866                                 sg_build_reserve(sfp, val);
 867                         }
 868                 } else {
 869                         if (sdp->detached)
 870                                 return -ENODEV;
 871                         sfp->low_dma = sdp->device->host->unchecked_isa_dma;
 872                 }
 873                 return 0;
 874         case SG_GET_LOW_DMA:
 875                 return put_user((int) sfp->low_dma, ip);
 876         case SG_GET_SCSI_ID:
 877                 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
 878                         return -EFAULT;
 879                 else {
 880                         sg_scsi_id_t __user *sg_idp = p;
 881
 882                         if (sdp->detached)
 883                                 return -ENODEV;
 884                         __put_user((int) sdp->device->host->host_no,
 885                                    &sg_idp->host_no);
 886                         __put_user((int) sdp->device->channel,
 887                                    &sg_idp->channel);
 888                         __put_user((int) sdp->device->id, &sg_idp->scsi_id);
 889                         __put_user((int) sdp->device->lun, &sg_idp->lun);
 890                         __put_user((int) sdp->device->type, &sg_idp->scsi_type);
 891                         __put_user((short) sdp->device->host->cmd_per_lun,
 892                                    &sg_idp->h_cmd_per_lun);
 893                         __put_user((short) sdp->device->queue_depth,
 894                                    &sg_idp->d_queue_depth);
 895                         __put_user(0, &sg_idp->unused[0]);
 896                         __put_user(0, &sg_idp->unused[1]);
 897                         return 0;
 898                 }
 899         case SG_SET_FORCE_PACK_ID:
 900                 result = get_user(val, ip);
 901                 if (result)
 902                         return result;
 903                 sfp->force_packid = val ? 1 : 0;
 904                 return 0;
 905         case SG_GET_PACK_ID:
 906                 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
 907                         return -EFAULT;
 908                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 909                 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
 910                         if ((1 == srp->done) && (!srp->sg_io_owned)) {
 911                                 read_unlock_irqrestore(&sfp->rq_list_lock,
 912                                                        iflags);
 913                                 __put_user(srp->header.pack_id, ip);
 914                                 return 0;
 915                         }
 916                 }
 917                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 918                 __put_user(-1, ip);
 919                 return 0;
 920         case SG_GET_NUM_WAITING:
 921                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 922                 for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) {
 923                         if ((1 == srp->done) && (!srp->sg_io_owned))
 924                                 ++val;
 925                 }
 926                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 927                 return put_user(val, ip);
 928         case SG_GET_SG_TABLESIZE:
 929                 return put_user(sdp->sg_tablesize, ip);
 930         case SG_SET_RESERVED_SIZE:
 931                 result = get_user(val, ip);
 932                 if (result)
 933                         return result;
 934                 if (val < 0)
 935                         return -EINVAL;
 936                 val = min_t(int, val,
 937                                 sdp->device->request_queue->max_sectors * 512);
 938                 if (val != sfp->reserve.bufflen) {
 939                         if (sg_res_in_use(sfp) || sfp->mmap_called)
 940                                 return -EBUSY;
 941                         sg_remove_scat(&sfp->reserve);
 942                         sg_build_reserve(sfp, val);
 943                 }
 944                 return 0;
 945         case SG_GET_RESERVED_SIZE:
 946                 val = min_t(int, sfp->reserve.bufflen,
 947                                 sdp->device->request_queue->max_sectors * 512);
 948                 return put_user(val, ip);
 949         case SG_SET_COMMAND_Q:
 950                 result = get_user(val, ip);
 951                 if (result)
 952                         return result;
 953                 sfp->cmd_q = val ? 1 : 0;
 954                 return 0;
 955         case SG_GET_COMMAND_Q:
 956                 return put_user((int) sfp->cmd_q, ip);
 957         case SG_SET_KEEP_ORPHAN:
 958                 result = get_user(val, ip);
 959                 if (result)
 960                         return result;
 961                 sfp->keep_orphan = val;
 962                 return 0;
 963         case SG_GET_KEEP_ORPHAN:
 964                 return put_user((int) sfp->keep_orphan, ip);
 965         case SG_NEXT_CMD_LEN:
 966                 result = get_user(val, ip);
 967                 if (result)
 968                         return result;
 969                 sfp->next_cmd_len = (val > 0) ? val : 0;
 970                 return 0;
 971         case SG_GET_VERSION_NUM:
 972                 return put_user(sg_version_num, ip);
 973         case SG_GET_ACCESS_COUNT:
 974                 /* faked - we don't have a real access count anymore */
 975                 val = (sdp->device ? 1 : 0);
 976                 return put_user(val, ip);
 977         case SG_GET_REQUEST_TABLE:
 978                 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
 979                         return -EFAULT;
 980                 else {
 981                         sg_req_info_t *rinfo;
 982                         unsigned int ms;
 983
 984                         rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
 985                                                                 GFP_KERNEL);
 986                         if (!rinfo)
 987                                 return -ENOMEM;
 988                         read_lock_irqsave(&sfp->rq_list_lock, iflags);
 989                         for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE;
 990                              ++val, srp = srp ? srp->nextrp : srp) {
 991                                 memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
 992                                 if (srp) {
 993                                         rinfo[val].req_state = srp->done + 1;
 994                                         rinfo[val].problem =
 995                                             srp->header.masked_status &
 996                                             srp->header.host_status &
 997                                             srp->header.driver_status;
 998                                         if (srp->done)
 999                                                 rinfo[val].duration =
1000                                                         srp->header.duration;
1001                                         else {
1002                                                 ms = jiffies_to_msecs(jiffies);
1003                                                 rinfo[val].duration =
1004                                                     (ms > srp->header.duration) ?
1005                                                     (ms - srp->header.duration) : 0;
1006                                         }
1007                                         rinfo[val].orphan = srp->orphan;
1008                                         rinfo[val].sg_io_owned =
1009                                                         srp->sg_io_owned;
1010                                         rinfo[val].pack_id =
1011                                                         srp->header.pack_id;
1012                                         rinfo[val].usr_ptr =
1013                                                         srp->header.usr_ptr;
1014                                 }
1015                         }
1016                         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1017                         result = __copy_to_user(p, rinfo,
1018                                                 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1019                         result = result ? -EFAULT : 0;
1020                         kfree(rinfo);
1021                         return result;
1022                 }
1023         case SG_EMULATED_HOST:
1024                 if (sdp->detached)
1025                         return -ENODEV;
1026                 return put_user(sdp->device->host->hostt->emulated, ip);
1027         case SG_SCSI_RESET:
1028                 if (sdp->detached)
1029                         return -ENODEV;
1030                 if (filp->f_flags & O_NONBLOCK) {
1031                         if (scsi_host_in_recovery(sdp->device->host))
1032                                 return -EBUSY;
1033                 } else if (!scsi_block_when_processing_errors(sdp->device))
1034                         return -EBUSY;
1035                 result = get_user(val, ip);
1036                 if (result)
1037                         return result;
1038                 if (SG_SCSI_RESET_NOTHING == val)
1039                         return 0;
1040                 switch (val) {
1041                 case SG_SCSI_RESET_DEVICE:
1042                         val = SCSI_TRY_RESET_DEVICE;
1043                         break;
1044                 case SG_SCSI_RESET_TARGET:
1045                         val = SCSI_TRY_RESET_TARGET;
1046                         break;
1047                 case SG_SCSI_RESET_BUS:
1048                         val = SCSI_TRY_RESET_BUS;
1049                         break;
1050                 case SG_SCSI_RESET_HOST:
1051                         val = SCSI_TRY_RESET_HOST;
1052                         break;
1053                 default:
1054                         return -EINVAL;
1055                 }
1056                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1057                         return -EACCES;
1058                 return (scsi_reset_provider(sdp->device, val) ==
1059                         SUCCESS) ? 0 : -EIO;
1060         case SCSI_IOCTL_SEND_COMMAND:
1061                 if (sdp->detached)
1062                         return -ENODEV;
1063                 if (read_only) {
1064                         unsigned char opcode = WRITE_6;
1065                         Scsi_Ioctl_Command __user *siocp = p;
1066
1067                         if (copy_from_user(&opcode, siocp->data, 1))
1068                                 return -EFAULT;
1069                         if (sg_allow_access(filp, &opcode))
1070                                 return -EPERM;
1071                 }
1072                 return sg_scsi_ioctl(filp, sdp->device->request_queue, NULL, p);
1073         case SG_SET_DEBUG:
1074                 result = get_user(val, ip);
1075                 if (result)
1076                         return result;
1077                 sdp->sgdebug = (char) val;
1078                 return 0;
1079         case SCSI_IOCTL_GET_IDLUN:
1080         case SCSI_IOCTL_GET_BUS_NUMBER:
1081         case SCSI_IOCTL_PROBE_HOST:
1082         case SG_GET_TRANSFORM:
1083                 if (sdp->detached)
1084                         return -ENODEV;
1085                 return scsi_ioctl(sdp->device, cmd_in, p);
1086         case BLKSECTGET:
1087                 return put_user(sdp->device->request_queue->max_sectors * 512,
1088                                 ip);
1089         case BLKTRACESETUP:
1090                 return blk_trace_setup(sdp->device->request_queue,
1091                                        sdp->disk->disk_name,
1092                                        sdp->device->sdev_gendev.devt,
1093                                        (char *)arg);
1094         case BLKTRACESTART:
1095                 return blk_trace_startstop(sdp->device->request_queue, 1);
1096         case BLKTRACESTOP:
1097                 return blk_trace_startstop(sdp->device->request_queue, 0);
1098         case BLKTRACETEARDOWN:
1099                 return blk_trace_remove(sdp->device->request_queue);
1100         default:
1101                 if (read_only)
1102                         return -EPERM;  /* don't know so take safe approach */
1103                 return scsi_ioctl(sdp->device, cmd_in, p);
1104         }
1105 }
1106
1107 #ifdef CONFIG_COMPAT
1108 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1109 {
1110         Sg_device *sdp;
1111         Sg_fd *sfp;
1112         struct scsi_device *sdev;
1113
1114         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1115                 return -ENXIO;
1116
1117         sdev = sdp->device;
1118         if (sdev->host->hostt->compat_ioctl) {
1119                 int ret;
1120
1121                 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1122
1123                 return ret;
1124         }
1125
1126         return -ENOIOCTLCMD;
1127 }
1128 #endif
1129
1130 static unsigned int
1131 sg_poll(struct file *filp, poll_table * wait)
1132 {
1133         unsigned int res = 0;
1134         Sg_device *sdp;
1135         Sg_fd *sfp;
1136         Sg_request *srp;
1137         int count = 0;
1138         unsigned long iflags;
1139
1140         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))
1141             || sfp->closed)
1142                 return POLLERR;
1143         poll_wait(filp, &sfp->read_wait, wait);
1144         read_lock_irqsave(&sfp->rq_list_lock, iflags);
1145         for (srp = sfp->headrp; srp; srp = srp->nextrp) {
1146                 /* if any read waiting, flag it */
1147                 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1148                         res = POLLIN | POLLRDNORM;
1149                 ++count;
1150         }
1151         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1152
1153         if (sdp->detached)
1154                 res |= POLLHUP;
1155         else if (!sfp->cmd_q) {
1156                 if (0 == count)
1157                         res |= POLLOUT | POLLWRNORM;
1158         } else if (count < SG_MAX_QUEUE)
1159                 res |= POLLOUT | POLLWRNORM;
1160         SCSI_LOG_TIMEOUT(3, printk("sg_poll: %s, res=0x%x\n",
1161                                    sdp->disk->disk_name, (int) res));
1162         return res;
1163 }
1164
1165 static int
1166 sg_fasync(int fd, struct file *filp, int mode)
1167 {
1168         int retval;
1169         Sg_device *sdp;
1170         Sg_fd *sfp;
1171
1172         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1173                 return -ENXIO;
1174         SCSI_LOG_TIMEOUT(3, printk("sg_fasync: %s, mode=%d\n",
1175                                    sdp->disk->disk_name, mode));
1176
1177         retval = fasync_helper(fd, filp, mode, &sfp->async_qp);
1178         return (retval < 0) ? retval : 0;
1179 }
1180
1181 static int
1182 sg_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1183 {
1184         Sg_fd *sfp;
1185         unsigned long offset, len, sa;
1186         Sg_scatter_hold *rsv_schp;
1187         int k, length;
1188
1189         if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1190                 return VM_FAULT_SIGBUS;
1191         rsv_schp = &sfp->reserve;
1192         offset = vmf->pgoff << PAGE_SHIFT;
1193         if (offset >= rsv_schp->bufflen)
1194                 return VM_FAULT_SIGBUS;
1195         SCSI_LOG_TIMEOUT(3, printk("sg_vma_fault: offset=%lu, scatg=%d\n",
1196                                    offset, rsv_schp->k_use_sg));
1197         sa = vma->vm_start;
1198         length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1199         for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1200                 len = vma->vm_end - sa;
1201                 len = (len < length) ? len : length;
1202                 if (offset < len) {
1203                         struct page *page = nth_page(rsv_schp->pages[k],
1204                                                      offset >> PAGE_SHIFT);
1205                         get_page(page); /* increment page count */
1206                         vmf->page = page;
1207                         return 0; /* success */
1208                 }
1209                 sa += len;
1210                 offset -= len;
1211         }
1212
1213         return VM_FAULT_SIGBUS;
1214 }
1215
1216 static struct vm_operations_struct sg_mmap_vm_ops = {
1217         .fault = sg_vma_fault,
1218 };
1219
1220 static int
1221 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1222 {
1223         Sg_fd *sfp;
1224         unsigned long req_sz, len, sa;
1225         Sg_scatter_hold *rsv_schp;
1226         int k, length;
1227
1228         if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1229                 return -ENXIO;
1230         req_sz = vma->vm_end - vma->vm_start;
1231         SCSI_LOG_TIMEOUT(3, printk("sg_mmap starting, vm_start=%p, len=%d\n",
1232                                    (void *) vma->vm_start, (int) req_sz));
1233         if (vma->vm_pgoff)
1234                 return -EINVAL; /* want no offset */
1235         rsv_schp = &sfp->reserve;
1236         if (req_sz > rsv_schp->bufflen)
1237                 return -ENOMEM; /* cannot map more than reserved buffer */
1238
1239         sa = vma->vm_start;
1240         length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1241         for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1242                 len = vma->vm_end - sa;
1243                 len = (len < length) ? len : length;
1244                 sa += len;
1245         }
1246
1247         sfp->mmap_called = 1;
1248         vma->vm_flags |= VM_RESERVED;
1249         vma->vm_private_data = sfp;
1250         vma->vm_ops = &sg_mmap_vm_ops;
1251         return 0;
1252 }
1253
1254 /*
1255  * This function is a "bottom half" handler that is called by the mid
1256  * level when a command is completed (or has failed).
1257  */
1258 static void sg_rq_end_io(struct request *rq, int uptodate)
1259 {
1260         struct sg_request *srp = rq->end_io_data;
1261         Sg_device *sdp = NULL;
1262         Sg_fd *sfp;
1263         unsigned long iflags;
1264         unsigned int ms;
1265         char *sense;
1266         int result, resid;
1267
1268         if (NULL == srp) {
1269                 printk(KERN_ERR "sg_cmd_done: NULL request\n");
1270                 return;
1271         }
1272         sfp = srp->parentfp;
1273         if (sfp)
1274                 sdp = sfp->parentdp;
1275         if ((NULL == sdp) || sdp->detached) {
1276                 printk(KERN_INFO "sg_cmd_done: device detached\n");
1277                 return;
1278         }
1279
1280         sense = rq->sense;
1281         result = rq->errors;
1282         resid = rq->data_len;
1283
1284         SCSI_LOG_TIMEOUT(4, printk("sg_cmd_done: %s, pack_id=%d, res=0x%x\n",
1285                 sdp->disk->disk_name, srp->header.pack_id, result));
1286         srp->header.resid = resid;
1287         ms = jiffies_to_msecs(jiffies);
1288         srp->header.duration = (ms > srp->header.duration) ?
1289                                 (ms - srp->header.duration) : 0;
1290         if (0 != result) {
1291                 struct scsi_sense_hdr sshdr;
1292
1293                 srp->header.status = 0xff & result;
1294                 srp->header.masked_status = status_byte(result);
1295                 srp->header.msg_status = msg_byte(result);
1296                 srp->header.host_status = host_byte(result);
1297                 srp->header.driver_status = driver_byte(result);
1298                 if ((sdp->sgdebug > 0) &&
1299                     ((CHECK_CONDITION == srp->header.masked_status) ||
1300                      (COMMAND_TERMINATED == srp->header.masked_status)))
1301                         __scsi_print_sense("sg_cmd_done", sense,
1302                                            SCSI_SENSE_BUFFERSIZE);
1303
1304                 /* Following if statement is a patch supplied by Eric Youngdale */
1305                 if (driver_byte(result) != 0
1306                     && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1307                     && !scsi_sense_is_deferred(&sshdr)
1308                     && sshdr.sense_key == UNIT_ATTENTION
1309                     && sdp->device->removable) {
1310                         /* Detected possible disc change. Set the bit - this */
1311                         /* may be used if there are filesystems using this device */
1312                         sdp->device->changed = 1;
1313                 }
1314         }
1315         /* Rely on write phase to clean out srp status values, so no "else" */
1316
1317         if (sfp->closed) {      /* whoops this fd already released, cleanup */
1318                 SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, freeing ...\n"));
1319                 sg_finish_rem_req(srp);
1320                 srp = NULL;
1321                 if (NULL == sfp->headrp) {
1322                         SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, final cleanup\n"));
1323                         if (0 == sg_remove_sfp(sdp, sfp)) {     /* device still present */
1324                                 scsi_device_put(sdp->device);
1325                         }
1326                         sfp = NULL;
1327                 }
1328         } else if (srp && srp->orphan) {
1329                 if (sfp->keep_orphan)
1330                         srp->sg_io_owned = 0;
1331                 else {
1332                         sg_finish_rem_req(srp);
1333                         srp = NULL;
1334                 }
1335         }
1336         if (sfp && srp) {
1337                 /* Now wake up any sg_read() that is waiting for this packet. */
1338                 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1339                 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1340                 srp->done = 1;
1341                 wake_up_interruptible(&sfp->read_wait);
1342                 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1343         }
1344 }
1345
1346 static struct file_operations sg_fops = {
1347         .owner = THIS_MODULE,
1348         .read = sg_read,
1349         .write = sg_write,
1350         .poll = sg_poll,
1351         .ioctl = sg_ioctl,
1352 #ifdef CONFIG_COMPAT
1353         .compat_ioctl = sg_compat_ioctl,
1354 #endif
1355         .open = sg_open,
1356         .mmap = sg_mmap,
1357         .release = sg_release,
1358         .fasync = sg_fasync,
1359 };
1360
1361 static struct class *sg_sysfs_class;
1362
1363 static int sg_sysfs_valid = 0;
1364
1365 static Sg_device *sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1366 {
1367         struct request_queue *q = scsidp->request_queue;
1368         Sg_device *sdp;
1369         unsigned long iflags;
1370         int error;
1371         u32 k;
1372
1373         sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1374         if (!sdp) {
1375                 printk(KERN_WARNING "kmalloc Sg_device failure\n");
1376                 return ERR_PTR(-ENOMEM);
1377         }
1378         error = -ENOMEM;
1379         if (!idr_pre_get(&sg_index_idr, GFP_KERNEL)) {
1380                 printk(KERN_WARNING "idr expansion Sg_device failure\n");
1381                 goto out;
1382         }
1383
1384         write_lock_irqsave(&sg_index_lock, iflags);
1385         error = idr_get_new(&sg_index_idr, sdp, &k);
1386         write_unlock_irqrestore(&sg_index_lock, iflags);
1387
1388         if (error) {
1389                 printk(KERN_WARNING "idr allocation Sg_device failure: %d\n",
1390                        error);
1391                 goto out;
1392         }
1393
1394         if (unlikely(k >= SG_MAX_DEVS))
1395                 goto overflow;
1396
1397         SCSI_LOG_TIMEOUT(3, printk("sg_alloc: dev=%d \n", k));
1398         sprintf(disk->disk_name, "sg%d", k);
1399         disk->first_minor = k;
1400         sdp->disk = disk;
1401         sdp->device = scsidp;
1402         init_waitqueue_head(&sdp->o_excl_wait);
1403         sdp->sg_tablesize = min(q->max_hw_segments, q->max_phys_segments);
1404         sdp->index = k;
1405
1406         error = 0;
1407  out:
1408         if (error) {
1409                 kfree(sdp);
1410                 return ERR_PTR(error);
1411         }
1412         return sdp;
1413
1414  overflow:
1415         sdev_printk(KERN_WARNING, scsidp,
1416                     "Unable to attach sg device type=%d, minor "
1417                     "number exceeds %d\n", scsidp->type, SG_MAX_DEVS - 1);
1418         error = -ENODEV;
1419         goto out;
1420 }
1421
1422 static int
1423 sg_add(struct device *cl_dev, struct class_interface *cl_intf)
1424 {
1425         struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1426         struct gendisk *disk;
1427         Sg_device *sdp = NULL;
1428         struct cdev * cdev = NULL;
1429         int error;
1430         unsigned long iflags;
1431
1432         disk = alloc_disk(1);
1433         if (!disk) {
1434                 printk(KERN_WARNING "alloc_disk failed\n");
1435                 return -ENOMEM;
1436         }
1437         disk->major = SCSI_GENERIC_MAJOR;
1438
1439         error = -ENOMEM;
1440         cdev = cdev_alloc();
1441         if (!cdev) {
1442                 printk(KERN_WARNING "cdev_alloc failed\n");
1443                 goto out;
1444         }
1445         cdev->owner = THIS_MODULE;
1446         cdev->ops = &sg_fops;
1447
1448         sdp = sg_alloc(disk, scsidp);
1449         if (IS_ERR(sdp)) {
1450                 printk(KERN_WARNING "sg_alloc failed\n");
1451                 error = PTR_ERR(sdp);
1452                 goto out;
1453         }
1454
1455         error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1456         if (error)
1457                 goto cdev_add_err;
1458
1459         sdp->cdev = cdev;
1460         if (sg_sysfs_valid) {
1461                 struct device *sg_class_member;
1462
1463                 sg_class_member = device_create_drvdata(sg_sysfs_class,
1464                                                         cl_dev->parent,
1465                                                         MKDEV(SCSI_GENERIC_MAJOR,
1466                                                               sdp->index),
1467                                                         sdp,
1468                                                         "%s", disk->disk_name);
1469                 if (IS_ERR(sg_class_member)) {
1470                         printk(KERN_ERR "sg_add: "
1471                                "device_create failed\n");
1472                         error = PTR_ERR(sg_class_member);
1473                         goto cdev_add_err;
1474                 }
1475                 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1476                                           &sg_class_member->kobj, "generic");
1477                 if (error)
1478                         printk(KERN_ERR "sg_add: unable to make symlink "
1479                                         "'generic' back to sg%d\n", sdp->index);
1480         } else
1481                 printk(KERN_WARNING "sg_add: sg_sys Invalid\n");
1482
1483         sdev_printk(KERN_NOTICE, scsidp,
1484                     "Attached scsi generic sg%d type %d\n", sdp->index,
1485                     scsidp->type);
1486
1487         dev_set_drvdata(cl_dev, sdp);
1488
1489         return 0;
1490
1491 cdev_add_err:
1492         write_lock_irqsave(&sg_index_lock, iflags);
1493         idr_remove(&sg_index_idr, sdp->index);
1494         write_unlock_irqrestore(&sg_index_lock, iflags);
1495         kfree(sdp);
1496
1497 out:
1498         put_disk(disk);
1499         if (cdev)
1500                 cdev_del(cdev);
1501         return error;
1502 }
1503
1504 static void
1505 sg_remove(struct device *cl_dev, struct class_interface *cl_intf)
1506 {
1507         struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1508         Sg_device *sdp = dev_get_drvdata(cl_dev);
1509         unsigned long iflags;
1510         Sg_fd *sfp;
1511         Sg_fd *tsfp;
1512         Sg_request *srp;
1513         Sg_request *tsrp;
1514         int delay;
1515
1516         if (!sdp)
1517                 return;
1518
1519         delay = 0;
1520         write_lock_irqsave(&sg_index_lock, iflags);
1521         if (sdp->headfp) {
1522                 sdp->detached = 1;
1523                 for (sfp = sdp->headfp; sfp; sfp = tsfp) {
1524                         tsfp = sfp->nextfp;
1525                         for (srp = sfp->headrp; srp; srp = tsrp) {
1526                                 tsrp = srp->nextrp;
1527                                 if (sfp->closed || (0 == sg_srp_done(srp, sfp)))
1528                                         sg_finish_rem_req(srp);
1529                         }
1530                         if (sfp->closed) {
1531                                 scsi_device_put(sdp->device);
1532                                 __sg_remove_sfp(sdp, sfp);
1533                         } else {
1534                                 delay = 1;
1535                                 wake_up_interruptible(&sfp->read_wait);
1536                                 kill_fasync(&sfp->async_qp, SIGPOLL,
1537                                             POLL_HUP);
1538                         }
1539                 }
1540                 SCSI_LOG_TIMEOUT(3, printk("sg_remove: dev=%d, dirty\n", sdp->index));
1541                 if (NULL == sdp->headfp) {
1542                         idr_remove(&sg_index_idr, sdp->index);
1543                 }
1544         } else {        /* nothing active, simple case */
1545                 SCSI_LOG_TIMEOUT(3, printk("sg_remove: dev=%d\n", sdp->index));
1546                 idr_remove(&sg_index_idr, sdp->index);
1547         }
1548         write_unlock_irqrestore(&sg_index_lock, iflags);
1549
1550         sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1551         device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1552         cdev_del(sdp->cdev);
1553         sdp->cdev = NULL;
1554         put_disk(sdp->disk);
1555         sdp->disk = NULL;
1556         if (NULL == sdp->headfp)
1557                 kfree(sdp);
1558
1559         if (delay)
1560                 msleep(10);     /* dirty detach so delay device destruction */
1561 }
1562
1563 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1564 module_param_named(def_reserved_size, def_reserved_size, int,
1565                    S_IRUGO | S_IWUSR);
1566 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1567
1568 MODULE_AUTHOR("Douglas Gilbert");
1569 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1570 MODULE_LICENSE("GPL");
1571 MODULE_VERSION(SG_VERSION_STR);
1572 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1573
1574 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1575                 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1576 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1577 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1578
1579 static int __init
1580 init_sg(void)
1581 {
1582         int rc;
1583
1584         if (scatter_elem_sz < PAGE_SIZE) {
1585                 scatter_elem_sz = PAGE_SIZE;
1586                 scatter_elem_sz_prev = scatter_elem_sz;
1587         }
1588         if (def_reserved_size >= 0)
1589                 sg_big_buff = def_reserved_size;
1590         else
1591                 def_reserved_size = sg_big_buff;
1592
1593         rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1594                                     SG_MAX_DEVS, "sg");
1595         if (rc)
1596                 return rc;
1597         sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1598         if ( IS_ERR(sg_sysfs_class) ) {
1599                 rc = PTR_ERR(sg_sysfs_class);
1600                 goto err_out;
1601         }
1602         sg_sysfs_valid = 1;
1603         rc = scsi_register_interface(&sg_interface);
1604         if (0 == rc) {
1605 #ifdef CONFIG_SCSI_PROC_FS
1606                 sg_proc_init();
1607 #endif                          /* CONFIG_SCSI_PROC_FS */
1608                 return 0;
1609         }
1610         class_destroy(sg_sysfs_class);
1611 err_out:
1612         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1613         return rc;
1614 }
1615
1616 static void __exit
1617 exit_sg(void)
1618 {
1619 #ifdef CONFIG_SCSI_PROC_FS
1620         sg_proc_cleanup();
1621 #endif                          /* CONFIG_SCSI_PROC_FS */
1622         scsi_unregister_interface(&sg_interface);
1623         class_destroy(sg_sysfs_class);
1624         sg_sysfs_valid = 0;
1625         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1626                                  SG_MAX_DEVS);
1627         idr_destroy(&sg_index_idr);
1628 }
1629
1630 static int __sg_start_req(struct sg_request *srp, struct sg_io_hdr *hp,
1631                           unsigned char *cmd)
1632 {
1633         struct sg_fd *sfp = srp->parentfp;
1634         struct request_queue *q = sfp->parentdp->device->request_queue;
1635         struct request *rq;
1636         int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
1637
1638         rq = blk_get_request(q, rw, GFP_ATOMIC);
1639         if (!rq)
1640                 return -ENOMEM;
1641
1642         memcpy(rq->cmd, cmd, hp->cmd_len);
1643
1644         rq->cmd_len = hp->cmd_len;
1645         rq->cmd_type = REQ_TYPE_BLOCK_PC;
1646
1647         srp->rq = rq;
1648         rq->end_io_data = srp;
1649         rq->sense = srp->sense_b;
1650         rq->retries = SG_DEFAULT_RETRIES;
1651
1652         return 0;
1653 }
1654
1655 static int sg_start_req(Sg_request *srp, unsigned char *cmd)
1656 {
1657         int res;
1658         Sg_fd *sfp = srp->parentfp;
1659         sg_io_hdr_t *hp = &srp->header;
1660         int dxfer_len = (int) hp->dxfer_len;
1661         int dxfer_dir = hp->dxfer_direction;
1662         Sg_scatter_hold *req_schp = &srp->data;
1663         Sg_scatter_hold *rsv_schp = &sfp->reserve;
1664         struct request_queue *q = sfp->parentdp->device->request_queue;
1665         struct rq_map_data map_data;
1666
1667         SCSI_LOG_TIMEOUT(4, printk("sg_start_req: dxfer_len=%d\n", dxfer_len));
1668
1669         res = __sg_start_req(srp, hp, cmd);
1670         if (res)
1671                 return res;
1672
1673         if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1674                 return 0;
1675
1676         if (sg_allow_dio && (hp->flags & SG_FLAG_DIRECT_IO) &&
1677             (dxfer_dir != SG_DXFER_UNKNOWN) && (0 == hp->iovec_count) &&
1678             (!sfp->parentdp->device->host->unchecked_isa_dma) &&
1679             blk_rq_aligned(q, hp->dxferp, dxfer_len))
1680                 return sg_build_direct(srp, sfp, dxfer_len);
1681
1682         if ((!sg_res_in_use(sfp)) && (dxfer_len <= rsv_schp->bufflen))
1683                 sg_link_reserve(sfp, srp, dxfer_len);
1684         else
1685                 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1686
1687         if (!res) {
1688                 struct request *rq = srp->rq;
1689                 Sg_scatter_hold *schp = &srp->data;
1690                 int iovec_count = (int) hp->iovec_count;
1691
1692                 map_data.pages = schp->pages;
1693                 map_data.page_order = schp->page_order;
1694                 map_data.nr_entries = schp->k_use_sg;
1695
1696                 if (iovec_count)
1697                         res = blk_rq_map_user_iov(q, rq, &map_data, hp->dxferp,
1698                                                   iovec_count,
1699                                                   hp->dxfer_len, GFP_ATOMIC);
1700                 else
1701                         res = blk_rq_map_user(q, rq, &map_data, hp->dxferp,
1702                                               hp->dxfer_len, GFP_ATOMIC);
1703
1704                 if (!res)
1705                         srp->bio = rq->bio;
1706         }
1707
1708         return res;
1709 }
1710
1711 static void
1712 sg_finish_rem_req(Sg_request * srp)
1713 {
1714         Sg_fd *sfp = srp->parentfp;
1715         Sg_scatter_hold *req_schp = &srp->data;
1716
1717         SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n", (int) srp->res_used));
1718         if (srp->res_used)
1719                 sg_unlink_reserve(sfp, srp);
1720         else
1721                 sg_remove_scat(req_schp);
1722
1723         if (srp->rq) {
1724                 if (srp->bio)
1725                         blk_rq_unmap_user(srp->bio);
1726
1727                 blk_put_request(srp->rq);
1728         }
1729
1730         sg_remove_request(sfp, srp);
1731 }
1732
1733 static int
1734 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1735 {
1736         int sg_bufflen = tablesize * sizeof(struct page *);
1737         gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1738
1739         schp->pages = kzalloc(sg_bufflen, gfp_flags);
1740         if (!schp->pages)
1741                 return -ENOMEM;
1742         schp->sglist_len = sg_bufflen;
1743         return tablesize;       /* number of scat_gath elements allocated */
1744 }
1745
1746 /* Returns: -ve -> error, 0 -> done, 1 -> try indirect */
1747 static int
1748 sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len)
1749 {
1750         sg_io_hdr_t *hp = &srp->header;
1751         Sg_scatter_hold *schp = &srp->data;
1752         int res;
1753         struct request *rq = srp->rq;
1754         struct request_queue *q = sfp->parentdp->device->request_queue;
1755
1756         res = blk_rq_map_user(q, rq, NULL, hp->dxferp, dxfer_len, GFP_ATOMIC);
1757         if (res)
1758                 return res;
1759         srp->bio = rq->bio;
1760         schp->dio_in_use = 1;
1761         hp->info |= SG_INFO_DIRECT_IO;
1762         return 0;
1763 }
1764
1765 static int
1766 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1767 {
1768         int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1769         int sg_tablesize = sfp->parentdp->sg_tablesize;
1770         int blk_size = buff_size, order;
1771         gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
1772
1773         if (blk_size < 0)
1774                 return -EFAULT;
1775         if (0 == blk_size)
1776                 ++blk_size;     /* don't know why */
1777 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1778         blk_size = (blk_size + SG_SECTOR_MSK) & (~SG_SECTOR_MSK);
1779         SCSI_LOG_TIMEOUT(4, printk("sg_build_indirect: buff_size=%d, blk_size=%d\n",
1780                                    buff_size, blk_size));
1781
1782         /* N.B. ret_sz carried into this block ... */
1783         mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1784         if (mx_sc_elems < 0)
1785                 return mx_sc_elems;     /* most likely -ENOMEM */
1786
1787         num = scatter_elem_sz;
1788         if (unlikely(num != scatter_elem_sz_prev)) {
1789                 if (num < PAGE_SIZE) {
1790                         scatter_elem_sz = PAGE_SIZE;
1791                         scatter_elem_sz_prev = PAGE_SIZE;
1792                 } else
1793                         scatter_elem_sz_prev = num;
1794         }
1795
1796         if (sfp->low_dma)
1797                 gfp_mask |= GFP_DMA;
1798
1799         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1800                 gfp_mask |= __GFP_ZERO;
1801
1802         order = get_order(num);
1803 retry:
1804         ret_sz = 1 << (PAGE_SHIFT + order);
1805
1806         for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1807              k++, rem_sz -= ret_sz) {
1808
1809                 num = (rem_sz > scatter_elem_sz_prev) ?
1810                         scatter_elem_sz_prev : rem_sz;
1811
1812                 schp->pages[k] = alloc_pages(gfp_mask, order);
1813                 if (!schp->pages[k])
1814                         goto out;
1815
1816                 if (num == scatter_elem_sz_prev) {
1817                         if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1818                                 scatter_elem_sz = ret_sz;
1819                                 scatter_elem_sz_prev = ret_sz;
1820                         }
1821                 }
1822
1823                 SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k=%d, num=%d, "
1824                                  "ret_sz=%d\n", k, num, ret_sz));
1825         }               /* end of for loop */
1826
1827         schp->page_order = order;
1828         schp->k_use_sg = k;
1829         SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, "
1830                          "rem_sz=%d\n", k, rem_sz));
1831
1832         schp->bufflen = blk_size;
1833         if (rem_sz > 0) /* must have failed */
1834                 return -ENOMEM;
1835         return 0;
1836 out:
1837         for (i = 0; i < k; i++)
1838                 __free_pages(schp->pages[k], order);
1839
1840         if (--order >= 0)
1841                 goto retry;
1842
1843         return -ENOMEM;
1844 }
1845
1846 static int
1847 sg_write_xfer(Sg_request * srp)
1848 {
1849         sg_io_hdr_t *hp = &srp->header;
1850         Sg_scatter_hold *schp = &srp->data;
1851         int num_xfer = 0;
1852         int dxfer_dir = hp->dxfer_direction;
1853         int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
1854
1855         if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_TO_DEV == dxfer_dir) ||
1856             (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
1857                 num_xfer = (int) (new_interface ? hp->dxfer_len : hp->flags);
1858                 if (schp->bufflen < num_xfer)
1859                         num_xfer = schp->bufflen;
1860         }
1861         if ((num_xfer <= 0) || (schp->dio_in_use) ||
1862             (new_interface
1863              && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
1864                 return 0;
1865
1866         SCSI_LOG_TIMEOUT(4, printk("sg_write_xfer: num_xfer=%d, k_use_sg=%d\n",
1867                           num_xfer, schp->k_use_sg));
1868
1869         return 0;
1870 }
1871
1872 static void
1873 sg_remove_scat(Sg_scatter_hold * schp)
1874 {
1875         SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1876         if (schp->pages && schp->sglist_len > 0) {
1877                 if (!schp->dio_in_use) {
1878                         int k;
1879
1880                         for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1881                                 SCSI_LOG_TIMEOUT(5, printk(
1882                                     "sg_remove_scat: k=%d, pg=0x%p\n",
1883                                     k, schp->pages[k]));
1884                                 __free_pages(schp->pages[k], schp->page_order);
1885                         }
1886
1887                         kfree(schp->pages);
1888                 }
1889         }
1890         memset(schp, 0, sizeof (*schp));
1891 }
1892
1893 static int
1894 sg_read_xfer(Sg_request * srp)
1895 {
1896         sg_io_hdr_t *hp = &srp->header;
1897         Sg_scatter_hold *schp = &srp->data;
1898         int num_xfer = 0;
1899         int dxfer_dir = hp->dxfer_direction;
1900         int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
1901
1902         if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_FROM_DEV == dxfer_dir)
1903             || (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
1904                 num_xfer = hp->dxfer_len;
1905                 if (schp->bufflen < num_xfer)
1906                         num_xfer = schp->bufflen;
1907         }
1908         if ((num_xfer <= 0) || (schp->dio_in_use) ||
1909             (new_interface
1910              && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
1911                 return 0;
1912
1913         SCSI_LOG_TIMEOUT(4, printk("sg_read_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
1914                           num_xfer, (int)hp->iovec_count, schp->k_use_sg));
1915         return 0;
1916 }
1917
1918 static int
1919 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1920 {
1921         Sg_scatter_hold *schp = &srp->data;
1922         int k, num;
1923
1924         SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n",
1925                                    num_read_xfer));
1926         if ((!outp) || (num_read_xfer <= 0))
1927                 return 0;
1928
1929         blk_rq_unmap_user(srp->bio);
1930         srp->bio = NULL;
1931
1932         num = 1 << (PAGE_SHIFT + schp->page_order);
1933         for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1934                 if (num > num_read_xfer) {
1935                         if (__copy_to_user(outp, page_address(schp->pages[k]),
1936                                            num_read_xfer))
1937                                 return -EFAULT;
1938                         break;
1939                 } else {
1940                         if (__copy_to_user(outp, page_address(schp->pages[k]),
1941                                            num))
1942                                 return -EFAULT;
1943                         num_read_xfer -= num;
1944                         if (num_read_xfer <= 0)
1945                                 break;
1946                         outp += num;
1947                 }
1948         }
1949
1950         return 0;
1951 }
1952
1953 static void
1954 sg_build_reserve(Sg_fd * sfp, int req_size)
1955 {
1956         Sg_scatter_hold *schp = &sfp->reserve;
1957
1958         SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
1959         do {
1960                 if (req_size < PAGE_SIZE)
1961                         req_size = PAGE_SIZE;
1962                 if (0 == sg_build_indirect(schp, sfp, req_size))
1963                         return;
1964                 else
1965                         sg_remove_scat(schp);
1966                 req_size >>= 1; /* divide by 2 */
1967         } while (req_size > (PAGE_SIZE / 2));
1968 }
1969
1970 static void
1971 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
1972 {
1973         Sg_scatter_hold *req_schp = &srp->data;
1974         Sg_scatter_hold *rsv_schp = &sfp->reserve;
1975         int k, num, rem;
1976
1977         srp->res_used = 1;
1978         SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
1979         rem = size;
1980
1981         num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1982         for (k = 0; k < rsv_schp->k_use_sg; k++) {
1983                 if (rem <= num) {
1984                         req_schp->k_use_sg = k + 1;
1985                         req_schp->sglist_len = rsv_schp->sglist_len;
1986                         req_schp->pages = rsv_schp->pages;
1987
1988                         req_schp->bufflen = size;
1989                         req_schp->b_malloc_len = rsv_schp->b_malloc_len;
1990                         req_schp->page_order = rsv_schp->page_order;
1991                         break;
1992                 } else
1993                         rem -= num;
1994         }
1995
1996         if (k >= rsv_schp->k_use_sg)
1997                 SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
1998 }
1999
2000 static void
2001 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2002 {
2003         Sg_scatter_hold *req_schp = &srp->data;
2004
2005         SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->k_use_sg=%d\n",
2006                                    (int) req_schp->k_use_sg));
2007         req_schp->k_use_sg = 0;
2008         req_schp->bufflen = 0;
2009         req_schp->pages = NULL;
2010         req_schp->page_order = 0;
2011         req_schp->sglist_len = 0;
2012         sfp->save_scat_len = 0;
2013         srp->res_used = 0;
2014 }
2015
2016 static Sg_request *
2017 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2018 {
2019         Sg_request *resp;
2020         unsigned long iflags;
2021
2022         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2023         for (resp = sfp->headrp; resp; resp = resp->nextrp) {
2024                 /* look for requests that are ready + not SG_IO owned */
2025                 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2026                     ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2027                         resp->done = 2; /* guard against other readers */
2028                         break;
2029                 }
2030         }
2031         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2032         return resp;
2033 }
2034
2035 #ifdef CONFIG_SCSI_PROC_FS
2036 static Sg_request *
2037 sg_get_nth_request(Sg_fd * sfp, int nth)
2038 {
2039         Sg_request *resp;
2040         unsigned long iflags;
2041         int k;
2042
2043         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2044         for (k = 0, resp = sfp->headrp; resp && (k < nth);
2045              ++k, resp = resp->nextrp) ;
2046         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2047         return resp;
2048 }
2049 #endif
2050
2051 /* always adds to end of list */
2052 static Sg_request *
2053 sg_add_request(Sg_fd * sfp)
2054 {
2055         int k;
2056         unsigned long iflags;
2057         Sg_request *resp;
2058         Sg_request *rp = sfp->req_arr;
2059
2060         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2061         resp = sfp->headrp;
2062         if (!resp) {
2063                 memset(rp, 0, sizeof (Sg_request));
2064                 rp->parentfp = sfp;
2065                 resp = rp;
2066                 sfp->headrp = resp;
2067         } else {
2068                 if (0 == sfp->cmd_q)
2069                         resp = NULL;    /* command queuing disallowed */
2070                 else {
2071                         for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2072                                 if (!rp->parentfp)
2073                                         break;
2074                         }
2075                         if (k < SG_MAX_QUEUE) {
2076                                 memset(rp, 0, sizeof (Sg_request));
2077                                 rp->parentfp = sfp;
2078                                 while (resp->nextrp)
2079                                         resp = resp->nextrp;
2080                                 resp->nextrp = rp;
2081                                 resp = rp;
2082                         } else
2083                                 resp = NULL;
2084                 }
2085         }
2086         if (resp) {
2087                 resp->nextrp = NULL;
2088                 resp->header.duration = jiffies_to_msecs(jiffies);
2089         }
2090         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2091         return resp;
2092 }
2093
2094 /* Return of 1 for found; 0 for not found */
2095 static int
2096 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2097 {
2098         Sg_request *prev_rp;
2099         Sg_request *rp;
2100         unsigned long iflags;
2101         int res = 0;
2102
2103         if ((!sfp) || (!srp) || (!sfp->headrp))
2104                 return res;
2105         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2106         prev_rp = sfp->headrp;
2107         if (srp == prev_rp) {
2108                 sfp->headrp = prev_rp->nextrp;
2109                 prev_rp->parentfp = NULL;
2110                 res = 1;
2111         } else {
2112                 while ((rp = prev_rp->nextrp)) {
2113                         if (srp == rp) {
2114                                 prev_rp->nextrp = rp->nextrp;
2115                                 rp->parentfp = NULL;
2116                                 res = 1;
2117                                 break;
2118                         }
2119                         prev_rp = rp;
2120                 }
2121         }
2122         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2123         return res;
2124 }
2125
2126 #ifdef CONFIG_SCSI_PROC_FS
2127 static Sg_fd *
2128 sg_get_nth_sfp(Sg_device * sdp, int nth)
2129 {
2130         Sg_fd *resp;
2131         unsigned long iflags;
2132         int k;
2133
2134         read_lock_irqsave(&sg_index_lock, iflags);
2135         for (k = 0, resp = sdp->headfp; resp && (k < nth);
2136              ++k, resp = resp->nextfp) ;
2137         read_unlock_irqrestore(&sg_index_lock, iflags);
2138         return resp;
2139 }
2140 #endif
2141
2142 static Sg_fd *
2143 sg_add_sfp(Sg_device * sdp, int dev)
2144 {
2145         Sg_fd *sfp;
2146         unsigned long iflags;
2147         int bufflen;
2148
2149         sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2150         if (!sfp)
2151                 return NULL;
2152
2153         init_waitqueue_head(&sfp->read_wait);
2154         rwlock_init(&sfp->rq_list_lock);
2155
2156         sfp->timeout = SG_DEFAULT_TIMEOUT;
2157         sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2158         sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2159         sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
2160             sdp->device->host->unchecked_isa_dma : 1;
2161         sfp->cmd_q = SG_DEF_COMMAND_Q;
2162         sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2163         sfp->parentdp = sdp;
2164         write_lock_irqsave(&sg_index_lock, iflags);
2165         if (!sdp->headfp)
2166                 sdp->headfp = sfp;
2167         else {                  /* add to tail of existing list */
2168                 Sg_fd *pfp = sdp->headfp;
2169                 while (pfp->nextfp)
2170                         pfp = pfp->nextfp;
2171                 pfp->nextfp = sfp;
2172         }
2173         write_unlock_irqrestore(&sg_index_lock, iflags);
2174         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));
2175         if (unlikely(sg_big_buff != def_reserved_size))
2176                 sg_big_buff = def_reserved_size;
2177
2178         bufflen = min_t(int, sg_big_buff,
2179                         sdp->device->request_queue->max_sectors * 512);
2180         sg_build_reserve(sfp, bufflen);
2181         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp:   bufflen=%d, k_use_sg=%d\n",
2182                            sfp->reserve.bufflen, sfp->reserve.k_use_sg));
2183         return sfp;
2184 }
2185
2186 static void
2187 __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2188 {
2189         Sg_fd *fp;
2190         Sg_fd *prev_fp;
2191
2192         prev_fp = sdp->headfp;
2193         if (sfp == prev_fp)
2194                 sdp->headfp = prev_fp->nextfp;
2195         else {
2196                 while ((fp = prev_fp->nextfp)) {
2197                         if (sfp == fp) {
2198                                 prev_fp->nextfp = fp->nextfp;
2199                                 break;
2200                         }
2201                         prev_fp = fp;
2202                 }
2203         }
2204         if (sfp->reserve.bufflen > 0) {
2205                 SCSI_LOG_TIMEOUT(6,
2206                         printk("__sg_remove_sfp:    bufflen=%d, k_use_sg=%d\n",
2207                         (int) sfp->reserve.bufflen, (int) sfp->reserve.k_use_sg));
2208                 sg_remove_scat(&sfp->reserve);
2209         }
2210         sfp->parentdp = NULL;
2211         SCSI_LOG_TIMEOUT(6, printk("__sg_remove_sfp:    sfp=0x%p\n", sfp));
2212         kfree(sfp);
2213 }
2214
2215 /* Returns 0 in normal case, 1 when detached and sdp object removed */
2216 static int
2217 sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2218 {
2219         Sg_request *srp;
2220         Sg_request *tsrp;
2221         int dirty = 0;
2222         int res = 0;
2223
2224         for (srp = sfp->headrp; srp; srp = tsrp) {
2225                 tsrp = srp->nextrp;
2226                 if (sg_srp_done(srp, sfp))
2227                         sg_finish_rem_req(srp);
2228                 else
2229                         ++dirty;
2230         }
2231         if (0 == dirty) {
2232                 unsigned long iflags;
2233
2234                 write_lock_irqsave(&sg_index_lock, iflags);
2235                 __sg_remove_sfp(sdp, sfp);
2236                 if (sdp->detached && (NULL == sdp->headfp)) {
2237                         idr_remove(&sg_index_idr, sdp->index);
2238                         kfree(sdp);
2239                         res = 1;
2240                 }
2241                 write_unlock_irqrestore(&sg_index_lock, iflags);
2242         } else {
2243                 /* MOD_INC's to inhibit unloading sg and associated adapter driver */
2244                 /* only bump the access_count if we actually succeeded in
2245                  * throwing another counter on the host module */
2246                 scsi_device_get(sdp->device);   /* XXX: retval ignored? */
2247                 sfp->closed = 1;        /* flag dirty state on this fd */
2248                 SCSI_LOG_TIMEOUT(1, printk("sg_remove_sfp: worrisome, %d writes pending\n",
2249                                   dirty));
2250         }
2251         return res;
2252 }
2253
2254 static int
2255 sg_res_in_use(Sg_fd * sfp)
2256 {
2257         const Sg_request *srp;
2258         unsigned long iflags;
2259
2260         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2261         for (srp = sfp->headrp; srp; srp = srp->nextrp)
2262                 if (srp->res_used)
2263                         break;
2264         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2265         return srp ? 1 : 0;
2266 }
2267
2268 #ifdef CONFIG_SCSI_PROC_FS
2269 static int
2270 sg_idr_max_id(int id, void *p, void *data)
2271 {
2272         int *k = data;
2273
2274         if (*k < id)
2275                 *k = id;
2276
2277         return 0;
2278 }
2279
2280 static int
2281 sg_last_dev(void)
2282 {
2283         int k = -1;
2284         unsigned long iflags;
2285
2286         read_lock_irqsave(&sg_index_lock, iflags);
2287         idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2288         read_unlock_irqrestore(&sg_index_lock, iflags);
2289         return k + 1;           /* origin 1 */
2290 }
2291 #endif
2292
2293 static Sg_device *
2294 sg_get_dev(int dev)
2295 {
2296         Sg_device *sdp;
2297         unsigned long iflags;
2298
2299         read_lock_irqsave(&sg_index_lock, iflags);
2300         sdp = idr_find(&sg_index_idr, dev);
2301         read_unlock_irqrestore(&sg_index_lock, iflags);
2302
2303         return sdp;
2304 }
2305
2306 #ifdef CONFIG_SCSI_PROC_FS
2307
2308 static struct proc_dir_entry *sg_proc_sgp = NULL;
2309
2310 static char sg_proc_sg_dirname[] = "scsi/sg";
2311
2312 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2313
2314 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2315 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2316                                   size_t count, loff_t *off);
2317 static struct file_operations adio_fops = {
2318         /* .owner, .read and .llseek added in sg_proc_init() */
2319         .open = sg_proc_single_open_adio,
2320         .write = sg_proc_write_adio,
2321         .release = single_release,
2322 };
2323
2324 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2325 static ssize_t sg_proc_write_dressz(struct file *filp,
2326                 const char __user *buffer, size_t count, loff_t *off);
2327 static struct file_operations dressz_fops = {
2328         .open = sg_proc_single_open_dressz,
2329         .write = sg_proc_write_dressz,
2330         .release = single_release,
2331 };
2332
2333 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2334 static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2335 static struct file_operations version_fops = {
2336         .open = sg_proc_single_open_version,
2337         .release = single_release,
2338 };
2339
2340 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2341 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2342 static struct file_operations devhdr_fops = {
2343         .open = sg_proc_single_open_devhdr,
2344         .release = single_release,
2345 };
2346
2347 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2348 static int sg_proc_open_dev(struct inode *inode, struct file *file);
2349 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2350 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2351 static void dev_seq_stop(struct seq_file *s, void *v);
2352 static struct file_operations dev_fops = {
2353         .open = sg_proc_open_dev,
2354         .release = seq_release,
2355 };
2356 static struct seq_operations dev_seq_ops = {
2357         .start = dev_seq_start,
2358         .next  = dev_seq_next,
2359         .stop  = dev_seq_stop,
2360         .show  = sg_proc_seq_show_dev,
2361 };
2362
2363 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2364 static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2365 static struct file_operations devstrs_fops = {
2366         .open = sg_proc_open_devstrs,
2367         .release = seq_release,
2368 };
2369 static struct seq_operations devstrs_seq_ops = {
2370         .start = dev_seq_start,
2371         .next  = dev_seq_next,
2372         .stop  = dev_seq_stop,
2373         .show  = sg_proc_seq_show_devstrs,
2374 };
2375
2376 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2377 static int sg_proc_open_debug(struct inode *inode, struct file *file);
2378 static struct file_operations debug_fops = {
2379         .open = sg_proc_open_debug,
2380         .release = seq_release,
2381 };
2382 static struct seq_operations debug_seq_ops = {
2383         .start = dev_seq_start,
2384         .next  = dev_seq_next,
2385         .stop  = dev_seq_stop,
2386         .show  = sg_proc_seq_show_debug,
2387 };
2388
2389
2390 struct sg_proc_leaf {
2391         const char * name;
2392         struct file_operations * fops;
2393 };
2394
2395 static struct sg_proc_leaf sg_proc_leaf_arr[] = {
2396         {"allow_dio", &adio_fops},
2397         {"debug", &debug_fops},
2398         {"def_reserved_size", &dressz_fops},
2399         {"device_hdr", &devhdr_fops},
2400         {"devices", &dev_fops},
2401         {"device_strs", &devstrs_fops},
2402         {"version", &version_fops}
2403 };
2404
2405 static int
2406 sg_proc_init(void)
2407 {
2408         int k, mask;
2409         int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2410         struct sg_proc_leaf * leaf;
2411
2412         sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2413         if (!sg_proc_sgp)
2414                 return 1;
2415         for (k = 0; k < num_leaves; ++k) {
2416                 leaf = &sg_proc_leaf_arr[k];
2417                 mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2418                 leaf->fops->owner = THIS_MODULE;
2419                 leaf->fops->read = seq_read;
2420                 leaf->fops->llseek = seq_lseek;
2421                 proc_create(leaf->name, mask, sg_proc_sgp, leaf->fops);
2422         }
2423         return 0;
2424 }
2425
2426 static void
2427 sg_proc_cleanup(void)
2428 {
2429         int k;
2430         int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2431
2432         if (!sg_proc_sgp)
2433                 return;
2434         for (k = 0; k < num_leaves; ++k)
2435                 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2436         remove_proc_entry(sg_proc_sg_dirname, NULL);
2437 }
2438
2439
2440 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2441 {
2442         seq_printf(s, "%d\n", *((int *)s->private));
2443         return 0;
2444 }
2445
2446 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2447 {
2448         return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2449 }
2450
2451 static ssize_t
2452 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2453                    size_t count, loff_t *off)
2454 {
2455         int num;
2456         char buff[11];
2457
2458         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2459                 return -EACCES;
2460         num = (count < 10) ? count : 10;
2461         if (copy_from_user(buff, buffer, num))
2462                 return -EFAULT;
2463         buff[num] = '\0';
2464         sg_allow_dio = simple_strtoul(buff, NULL, 10) ? 1 : 0;
2465         return count;
2466 }
2467
2468 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2469 {
2470         return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2471 }
2472
2473 static ssize_t
2474 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2475                      size_t count, loff_t *off)
2476 {
2477         int num;
2478         unsigned long k = ULONG_MAX;
2479         char buff[11];
2480
2481         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2482                 return -EACCES;
2483         num = (count < 10) ? count : 10;
2484         if (copy_from_user(buff, buffer, num))
2485                 return -EFAULT;
2486         buff[num] = '\0';
2487         k = simple_strtoul(buff, NULL, 10);
2488         if (k <= 1048576) {     /* limit "big buff" to 1 MB */
2489                 sg_big_buff = k;
2490                 return count;
2491         }
2492         return -ERANGE;
2493 }
2494
2495 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2496 {
2497         seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2498                    sg_version_date);
2499         return 0;
2500 }
2501
2502 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2503 {
2504         return single_open(file, sg_proc_seq_show_version, NULL);
2505 }
2506
2507 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2508 {
2509         seq_printf(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\t"
2510                    "online\n");
2511         return 0;
2512 }
2513
2514 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2515 {
2516         return single_open(file, sg_proc_seq_show_devhdr, NULL);
2517 }
2518
2519 struct sg_proc_deviter {
2520         loff_t  index;
2521         size_t  max;
2522 };
2523
2524 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2525 {
2526         struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2527
2528         s->private = it;
2529         if (! it)
2530                 return NULL;
2531
2532         it->index = *pos;
2533         it->max = sg_last_dev();
2534         if (it->index >= it->max)
2535                 return NULL;
2536         return it;
2537 }
2538
2539 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2540 {
2541         struct sg_proc_deviter * it = s->private;
2542
2543         *pos = ++it->index;
2544         return (it->index < it->max) ? it : NULL;
2545 }
2546
2547 static void dev_seq_stop(struct seq_file *s, void *v)
2548 {
2549         kfree(s->private);
2550 }
2551
2552 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2553 {
2554         return seq_open(file, &dev_seq_ops);
2555 }
2556
2557 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2558 {
2559         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2560         Sg_device *sdp;
2561         struct scsi_device *scsidp;
2562
2563         sdp = it ? sg_get_dev(it->index) : NULL;
2564         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2565                 seq_printf(s, "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n",
2566                               scsidp->host->host_no, scsidp->channel,
2567                               scsidp->id, scsidp->lun, (int) scsidp->type,
2568                               1,
2569                               (int) scsidp->queue_depth,
2570                               (int) scsidp->device_busy,
2571                               (int) scsi_device_online(scsidp));
2572         else
2573                 seq_printf(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2574         return 0;
2575 }
2576
2577 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2578 {
2579         return seq_open(file, &devstrs_seq_ops);
2580 }
2581
2582 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2583 {
2584         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2585         Sg_device *sdp;
2586         struct scsi_device *scsidp;
2587
2588         sdp = it ? sg_get_dev(it->index) : NULL;
2589         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2590                 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2591                            scsidp->vendor, scsidp->model, scsidp->rev);
2592         else
2593                 seq_printf(s, "<no active device>\n");
2594         return 0;
2595 }
2596
2597 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2598 {
2599         int k, m, new_interface, blen, usg;
2600         Sg_request *srp;
2601         Sg_fd *fp;
2602         const sg_io_hdr_t *hp;
2603         const char * cp;
2604         unsigned int ms;
2605
2606         for (k = 0; (fp = sg_get_nth_sfp(sdp, k)); ++k) {
2607                 seq_printf(s, "   FD(%d): timeout=%dms bufflen=%d "
2608                            "(res)sgat=%d low_dma=%d\n", k + 1,
2609                            jiffies_to_msecs(fp->timeout),
2610                            fp->reserve.bufflen,
2611                            (int) fp->reserve.k_use_sg,
2612                            (int) fp->low_dma);
2613                 seq_printf(s, "   cmd_q=%d f_packid=%d k_orphan=%d closed=%d\n",
2614                            (int) fp->cmd_q, (int) fp->force_packid,
2615                            (int) fp->keep_orphan, (int) fp->closed);
2616                 for (m = 0; (srp = sg_get_nth_request(fp, m)); ++m) {
2617                         hp = &srp->header;
2618                         new_interface = (hp->interface_id == '\0') ? 0 : 1;
2619                         if (srp->res_used) {
2620                                 if (new_interface &&
2621                                     (SG_FLAG_MMAP_IO & hp->flags))
2622                                         cp = "     mmap>> ";
2623                                 else
2624                                         cp = "     rb>> ";
2625                         } else {
2626                                 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2627                                         cp = "     dio>> ";
2628                                 else
2629                                         cp = "     ";
2630                         }
2631                         seq_printf(s, cp);
2632                         blen = srp->data.bufflen;
2633                         usg = srp->data.k_use_sg;
2634                         seq_printf(s, srp->done ?
2635                                    ((1 == srp->done) ?  "rcv:" : "fin:")
2636                                    : "act:");
2637                         seq_printf(s, " id=%d blen=%d",
2638                                    srp->header.pack_id, blen);
2639                         if (srp->done)
2640                                 seq_printf(s, " dur=%d", hp->duration);
2641                         else {
2642                                 ms = jiffies_to_msecs(jiffies);
2643                                 seq_printf(s, " t_o/elap=%d/%d",
2644                                         (new_interface ? hp->timeout :
2645                                                   jiffies_to_msecs(fp->timeout)),
2646                                         (ms > hp->duration ? ms - hp->duration : 0));
2647                         }
2648                         seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2649                                    (int) srp->data.cmd_opcode);
2650                 }
2651                 if (0 == m)
2652                         seq_printf(s, "     No requests active\n");
2653         }
2654 }
2655
2656 static int sg_proc_open_debug(struct inode *inode, struct file *file)
2657 {
2658         return seq_open(file, &debug_seq_ops);
2659 }
2660
2661 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2662 {
2663         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2664         Sg_device *sdp;
2665
2666         if (it && (0 == it->index)) {
2667                 seq_printf(s, "max_active_device=%d(origin 1)\n",
2668                            (int)it->max);
2669                 seq_printf(s, " def_reserved_size=%d\n", sg_big_buff);
2670         }
2671         sdp = it ? sg_get_dev(it->index) : NULL;
2672         if (sdp) {
2673                 struct scsi_device *scsidp = sdp->device;
2674
2675                 if (NULL == scsidp) {
2676                         seq_printf(s, "device %d detached ??\n",
2677                                    (int)it->index);
2678                         return 0;
2679                 }
2680
2681                 if (sg_get_nth_sfp(sdp, 0)) {
2682                         seq_printf(s, " >>> device=%s ",
2683                                 sdp->disk->disk_name);
2684                         if (sdp->detached)
2685                                 seq_printf(s, "detached pending close ");
2686                         else
2687                                 seq_printf
2688                                     (s, "scsi%d chan=%d id=%d lun=%d   em=%d",
2689                                      scsidp->host->host_no,
2690                                      scsidp->channel, scsidp->id,
2691                                      scsidp->lun,
2692                                      scsidp->host->hostt->emulated);
2693                         seq_printf(s, " sg_tablesize=%d excl=%d\n",
2694                                    sdp->sg_tablesize, sdp->exclude);
2695                 }
2696                 sg_proc_debug_helper(s, sdp);
2697         }
2698         return 0;
2699 }
2700
2701 #endif                          /* CONFIG_SCSI_PROC_FS */
2702
2703 module_init(init_sg);
2704 module_exit(exit_sg);