drivers/scsi/sg.c

   1 /*
   2  *  History:
   3  *  Started: Aug 9 by Lawrence Foard (entropy@world.std.com),
   4  *           to allow user process control of SCSI devices.
   5  *  Development Sponsored by Killy Corp. NY NY
   6  *
   7  * Original driver (sg.c):
   8  *        Copyright (C) 1992 Lawrence Foard
   9  * Version 2 and 3 extensions to driver:
  10  *        Copyright (C) 1998 - 2005 Douglas Gilbert
  11  *
  12  *  Modified  19-JAN-1998  Richard Gooch <rgooch@atnf.csiro.au>  Devfs support
  13  *
  14  * This program is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2, or (at your option)
  17  * any later version.
  18  *
  19  */
  20
  21 static int sg_version_num = 30532;      /* 2 digits for each component */
  22 #define SG_VERSION_STR "3.5.32"
  23
  24 /*
  25  *  D. P. Gilbert (dgilbert@interlog.com, dougg@triode.net.au), notes:
  26  *      - scsi logging is available via SCSI_LOG_TIMEOUT macros. First
  27  *        the kernel/module needs to be built with CONFIG_SCSI_LOGGING
  28  *        (otherwise the macros compile to empty statements).
  29  *
  30  */
  31 #include <linux/config.h>
  32 #include <linux/module.h>
  33
  34 #include <linux/fs.h>
  35 #include <linux/kernel.h>
  36 #include <linux/sched.h>
  37 #include <linux/string.h>
  38 #include <linux/mm.h>
  39 #include <linux/errno.h>
  40 #include <linux/mtio.h>
  41 #include <linux/ioctl.h>
  42 #include <linux/fcntl.h>
  43 #include <linux/init.h>
  44 #include <linux/poll.h>
  45 #include <linux/smp_lock.h>
  46 #include <linux/moduleparam.h>
  47 #include <linux/devfs_fs_kernel.h>
  48 #include <linux/cdev.h>
  49 #include <linux/seq_file.h>
  50 #include <linux/blkdev.h>
  51 #include <linux/delay.h>
  52
  53 #include "scsi.h"
  54 #include <scsi/scsi_host.h>
  55 #include <scsi/scsi_driver.h>
  56 #include <scsi/scsi_ioctl.h>
  57 #include <scsi/sg.h>
  58
  59 #include "scsi_logging.h"
  60
  61 #ifdef CONFIG_SCSI_PROC_FS
  62 #include <linux/proc_fs.h>
  63 static char *sg_version_date = "20050117";
  64
  65 static int sg_proc_init(void);
  66 static void sg_proc_cleanup(void);
  67 #endif
  68
  69 #ifndef LINUX_VERSION_CODE
  70 #include <linux/version.h>
  71 #endif                          /* LINUX_VERSION_CODE */
  72
  73 #define SG_ALLOW_DIO_DEF 0
  74 #define SG_ALLOW_DIO_CODE /* compile out by commenting this define */
  75
  76 #define SG_MAX_DEVS 32768
  77
  78 /*
  79  * Suppose you want to calculate the formula muldiv(x,m,d)=int(x * m / d)
  80  * Then when using 32 bit integers x * m may overflow during the calculation.
  81  * Replacing muldiv(x) by muldiv(x)=((x % d) * m) / d + int(x / d) * m
  82  * calculates the same, but prevents the overflow when both m and d
  83  * are "small" numbers (like HZ and USER_HZ).
  84  * Of course an overflow is inavoidable if the result of muldiv doesn't fit
  85  * in 32 bits.
  86  */
  87 #define MULDIV(X,MUL,DIV) ((((X % DIV) * MUL) / DIV) + ((X / DIV) * MUL))
  88
  89 #define SG_DEFAULT_TIMEOUT MULDIV(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
  90
  91 int sg_big_buff = SG_DEF_RESERVED_SIZE;
  92 /* N.B. This variable is readable and writeable via
  93    /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
  94    of this size (or less if there is not enough memory) will be reserved
  95    for use by this file descriptor. [Deprecated usage: this variable is also
  96    readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
  97    the kernel (i.e. it is not a module).] */
  98 static int def_reserved_size = -1;      /* picks up init parameter */
  99 static int sg_allow_dio = SG_ALLOW_DIO_DEF;
 100
 101 #define SG_SECTOR_SZ 512
 102 #define SG_SECTOR_MSK (SG_SECTOR_SZ - 1)
 103
 104 #define SG_DEV_ARR_LUMP 32      /* amount to over allocate sg_dev_arr by */
 105
 106 static int sg_add(struct class_device *);
 107 static void sg_remove(struct class_device *);
 108
 109 static Scsi_Request *dummy_cmdp;        /* only used for sizeof */
 110
 111 static DEFINE_RWLOCK(sg_dev_arr_lock);  /* Also used to lock
 112                                                            file descriptor list for device */
 113
 114 static struct class_interface sg_interface = {
 115         .add            = sg_add,
 116         .remove         = sg_remove,
 117 };
 118
 119 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
 120         unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
 121         unsigned short sglist_len; /* size of malloc'd scatter-gather list ++ */
 122         unsigned bufflen;       /* Size of (aggregate) data buffer */
 123         unsigned b_malloc_len;  /* actual len malloc'ed in buffer */
 124         void *buffer;           /* Data buffer or scatter list (k_use_sg>0) */
 125         char dio_in_use;        /* 0->indirect IO (or mmap), 1->dio */
 126         unsigned char cmd_opcode; /* first byte of command */
 127 } Sg_scatter_hold;
 128
 129 struct sg_device;               /* forward declarations */
 130 struct sg_fd;
 131
 132 typedef struct sg_request {     /* SG_MAX_QUEUE requests outstanding per file */
 133         Scsi_Request *my_cmdp;  /* != 0  when request with lower levels */
 134         struct sg_request *nextrp;      /* NULL -> tail request (slist) */
 135         struct sg_fd *parentfp; /* NULL -> not in use */
 136         Sg_scatter_hold data;   /* hold buffer, perhaps scatter list */
 137         sg_io_hdr_t header;     /* scsi command+info, see <scsi/sg.h> */
 138         unsigned char sense_b[sizeof (dummy_cmdp->sr_sense_buffer)];
 139         char res_used;          /* 1 -> using reserve buffer, 0 -> not ... */
 140         char orphan;            /* 1 -> drop on sight, 0 -> normal */
 141         char sg_io_owned;       /* 1 -> packet belongs to SG_IO */
 142         volatile char done;     /* 0->before bh, 1->before read, 2->read */
 143 } Sg_request;
 144
 145 typedef struct sg_fd {          /* holds the state of a file descriptor */
 146         struct sg_fd *nextfp;   /* NULL when last opened fd on this device */
 147         struct sg_device *parentdp;     /* owning device */
 148         wait_queue_head_t read_wait;    /* queue read until command done */
 149         rwlock_t rq_list_lock;  /* protect access to list in req_arr */
 150         int timeout;            /* defaults to SG_DEFAULT_TIMEOUT      */
 151         int timeout_user;       /* defaults to SG_DEFAULT_TIMEOUT_USER */
 152         Sg_scatter_hold reserve;        /* buffer held for this file descriptor */
 153         unsigned save_scat_len; /* original length of trunc. scat. element */
 154         Sg_request *headrp;     /* head of request slist, NULL->empty */
 155         struct fasync_struct *async_qp; /* used by asynchronous notification */
 156         Sg_request req_arr[SG_MAX_QUEUE];       /* used as singly-linked list */
 157         char low_dma;           /* as in parent but possibly overridden to 1 */
 158         char force_packid;      /* 1 -> pack_id input to read(), 0 -> ignored */
 159         volatile char closed;   /* 1 -> fd closed but request(s) outstanding */
 160         char cmd_q;             /* 1 -> allow command queuing, 0 -> don't */
 161         char next_cmd_len;      /* 0 -> automatic (def), >0 -> use on next write() */
 162         char keep_orphan;       /* 0 -> drop orphan (def), 1 -> keep for read() */
 163         char mmap_called;       /* 0 -> mmap() never called on this fd */
 164 } Sg_fd;
 165
 166 typedef struct sg_device { /* holds the state of each scsi generic device */
 167         struct scsi_device *device;
 168         wait_queue_head_t o_excl_wait;  /* queue open() when O_EXCL in use */
 169         int sg_tablesize;       /* adapter's max scatter-gather table size */
 170         Sg_fd *headfp;          /* first open fd belonging to this device */
 171         volatile char detached; /* 0->attached, 1->detached pending removal */
 172         volatile char exclude;  /* opened for exclusive access */
 173         char sgdebug;           /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
 174         struct gendisk *disk;
 175         struct cdev * cdev;     /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
 176 } Sg_device;
 177
 178 static int sg_fasync(int fd, struct file *filp, int mode);
 179 static void sg_cmd_done(Scsi_Cmnd * SCpnt);     /* tasklet or soft irq callback */
 180 static int sg_start_req(Sg_request * srp);
 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, const char __user *buf, size_t count,
 188                             int blocking, int read_only, Sg_request ** o_srp);
 189 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
 190                            unsigned char *cmnd, int timeout, int blocking);
 191 static int sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
 192                       int wr_xf, int *countp, unsigned char __user **up);
 193 static int sg_write_xfer(Sg_request * srp);
 194 static int sg_read_xfer(Sg_request * srp);
 195 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
 196 static void sg_remove_scat(Sg_scatter_hold * schp);
 197 static void sg_build_reserve(Sg_fd * sfp, int req_size);
 198 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
 199 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
 200 static char *sg_page_malloc(int rqSz, int lowDma, int *retSzp);
 201 static void sg_page_free(char *buff, int size);
 202 static Sg_fd *sg_add_sfp(Sg_device * sdp, int dev);
 203 static int sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
 204 static void __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
 205 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
 206 static Sg_request *sg_add_request(Sg_fd * sfp);
 207 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
 208 static int sg_res_in_use(Sg_fd * sfp);
 209 static int sg_allow_access(unsigned char opcode, char dev_type);
 210 static int sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len);
 211 static Sg_device *sg_get_dev(int dev);
 212 static inline unsigned char *sg_scatg2virt(const struct scatterlist *sclp);
 213 #ifdef CONFIG_SCSI_PROC_FS
 214 static int sg_last_dev(void);
 215 #endif
 216
 217 static Sg_device **sg_dev_arr = NULL;
 218 static int sg_dev_max;
 219 static int sg_nr_dev;
 220
 221 #define SZ_SG_HEADER sizeof(struct sg_header)
 222 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
 223 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
 224 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
 225
 226 static int
 227 sg_open(struct inode *inode, struct file *filp)
 228 {
 229         int dev = iminor(inode);
 230         int flags = filp->f_flags;
 231         Sg_device *sdp;
 232         Sg_fd *sfp;
 233         int res;
 234         int retval;
 235
 236         nonseekable_open(inode, filp);
 237         SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags));
 238         sdp = sg_get_dev(dev);
 239         if ((!sdp) || (!sdp->device))
 240                 return -ENXIO;
 241         if (sdp->detached)
 242                 return -ENODEV;
 243
 244         /* This driver's module count bumped by fops_get in <linux/fs.h> */
 245         /* Prevent the device driver from vanishing while we sleep */
 246         retval = scsi_device_get(sdp->device);
 247         if (retval)
 248                 return retval;
 249
 250         if (!((flags & O_NONBLOCK) ||
 251               scsi_block_when_processing_errors(sdp->device))) {
 252                 retval = -ENXIO;
 253                 /* we are in error recovery for this device */
 254                 goto error_out;
 255         }
 256
 257         if (flags & O_EXCL) {
 258                 if (O_RDONLY == (flags & O_ACCMODE)) {
 259                         retval = -EPERM; /* Can't lock it with read only access */
 260                         goto error_out;
 261                 }
 262                 if (sdp->headfp && (flags & O_NONBLOCK)) {
 263                         retval = -EBUSY;
 264                         goto error_out;
 265                 }
 266                 res = 0;
 267                 __wait_event_interruptible(sdp->o_excl_wait,
 268                         ((sdp->headfp || sdp->exclude) ? 0 : (sdp->exclude = 1)), res);
 269                 if (res) {
 270                         retval = res;   /* -ERESTARTSYS because signal hit process */
 271                         goto error_out;
 272                 }
 273         } else if (sdp->exclude) {      /* some other fd has an exclusive lock on dev */
 274                 if (flags & O_NONBLOCK) {
 275                         retval = -EBUSY;
 276                         goto error_out;
 277                 }
 278                 res = 0;
 279                 __wait_event_interruptible(sdp->o_excl_wait, (!sdp->exclude),
 280                                            res);
 281                 if (res) {
 282                         retval = res;   /* -ERESTARTSYS because signal hit process */
 283                         goto error_out;
 284                 }
 285         }
 286         if (sdp->detached) {
 287                 retval = -ENODEV;
 288                 goto error_out;
 289         }
 290         if (!sdp->headfp) {     /* no existing opens on this device */
 291                 sdp->sgdebug = 0;
 292                 sdp->sg_tablesize = sdp->device->host->sg_tablesize;
 293         }
 294         if ((sfp = sg_add_sfp(sdp, dev)))
 295                 filp->private_data = sfp;
 296         else {
 297                 if (flags & O_EXCL)
 298                         sdp->exclude = 0;       /* undo if error */
 299                 retval = -ENOMEM;
 300                 goto error_out;
 301         }
 302         return 0;
 303
 304       error_out:
 305         scsi_device_put(sdp->device);
 306         return retval;
 307 }
 308
 309 /* Following function was formerly called 'sg_close' */
 310 static int
 311 sg_release(struct inode *inode, struct file *filp)
 312 {
 313         Sg_device *sdp;
 314         Sg_fd *sfp;
 315
 316         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 317                 return -ENXIO;
 318         SCSI_LOG_TIMEOUT(3, printk("sg_release: %s\n", sdp->disk->disk_name));
 319         sg_fasync(-1, filp, 0); /* remove filp from async notification list */
 320         if (0 == sg_remove_sfp(sdp, sfp)) {     /* Returns 1 when sdp gone */
 321                 if (!sdp->detached) {
 322                         scsi_device_put(sdp->device);
 323                 }
 324                 sdp->exclude = 0;
 325                 wake_up_interruptible(&sdp->o_excl_wait);
 326         }
 327         return 0;
 328 }
 329
 330 static ssize_t
 331 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
 332 {
 333         int res;
 334         Sg_device *sdp;
 335         Sg_fd *sfp;
 336         Sg_request *srp;
 337         int req_pack_id = -1;
 338         struct sg_header old_hdr;
 339         sg_io_hdr_t new_hdr;
 340         sg_io_hdr_t *hp;
 341
 342         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 343                 return -ENXIO;
 344         SCSI_LOG_TIMEOUT(3, printk("sg_read: %s, count=%d\n",
 345                                    sdp->disk->disk_name, (int) count));
 346         if (!access_ok(VERIFY_WRITE, buf, count))
 347                 return -EFAULT;
 348         if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
 349                 if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
 350                         return -EFAULT;
 351                 if (old_hdr.reply_len < 0) {
 352                         if (count >= SZ_SG_IO_HDR) {
 353                                 if (__copy_from_user
 354                                     (&new_hdr, buf, SZ_SG_IO_HDR))
 355                                         return -EFAULT;
 356                                 req_pack_id = new_hdr.pack_id;
 357                         }
 358                 } else
 359                         req_pack_id = old_hdr.pack_id;
 360         }
 361         srp = sg_get_rq_mark(sfp, req_pack_id);
 362         if (!srp) {             /* now wait on packet to arrive */
 363                 if (sdp->detached)
 364                         return -ENODEV;
 365                 if (filp->f_flags & O_NONBLOCK)
 366                         return -EAGAIN;
 367                 while (1) {
 368                         res = 0;        /* following is a macro that beats race condition */
 369                         __wait_event_interruptible(sfp->read_wait,
 370                                 (sdp->detached || (srp = sg_get_rq_mark(sfp, req_pack_id))),
 371                                                    res);
 372                         if (sdp->detached)
 373                                 return -ENODEV;
 374                         if (0 == res)
 375                                 break;
 376                         return res;     /* -ERESTARTSYS because signal hit process */
 377                 }
 378         }
 379         if (srp->header.interface_id != '\0')
 380                 return sg_new_read(sfp, buf, count, srp);
 381
 382         hp = &srp->header;
 383         memset(&old_hdr, 0, SZ_SG_HEADER);
 384         old_hdr.reply_len = (int) hp->timeout;
 385         old_hdr.pack_len = old_hdr.reply_len; /* very old, strange behaviour */
 386         old_hdr.pack_id = hp->pack_id;
 387         old_hdr.twelve_byte =
 388             ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
 389         old_hdr.target_status = hp->masked_status;
 390         old_hdr.host_status = hp->host_status;
 391         old_hdr.driver_status = hp->driver_status;
 392         if ((CHECK_CONDITION & hp->masked_status) ||
 393             (DRIVER_SENSE & hp->driver_status))
 394                 memcpy(old_hdr.sense_buffer, srp->sense_b,
 395                        sizeof (old_hdr.sense_buffer));
 396         switch (hp->host_status) {
 397         /* This setup of 'result' is for backward compatibility and is best
 398            ignored by the user who should use target, host + driver status */
 399         case DID_OK:
 400         case DID_PASSTHROUGH:
 401         case DID_SOFT_ERROR:
 402                 old_hdr.result = 0;
 403                 break;
 404         case DID_NO_CONNECT:
 405         case DID_BUS_BUSY:
 406         case DID_TIME_OUT:
 407                 old_hdr.result = EBUSY;
 408                 break;
 409         case DID_BAD_TARGET:
 410         case DID_ABORT:
 411         case DID_PARITY:
 412         case DID_RESET:
 413         case DID_BAD_INTR:
 414                 old_hdr.result = EIO;
 415                 break;
 416         case DID_ERROR:
 417                 old_hdr.result = (srp->sense_b[0] == 0 &&
 418                                   hp->masked_status == GOOD) ? 0 : EIO;
 419                 break;
 420         default:
 421                 old_hdr.result = EIO;
 422                 break;
 423         }
 424
 425         /* Now copy the result back to the user buffer.  */
 426         if (count >= SZ_SG_HEADER) {
 427                 if (__copy_to_user(buf, &old_hdr, SZ_SG_HEADER))
 428                         return -EFAULT;
 429                 buf += SZ_SG_HEADER;
 430                 if (count > old_hdr.reply_len)
 431                         count = old_hdr.reply_len;
 432                 if (count > SZ_SG_HEADER) {
 433                         if ((res =
 434                              sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)))
 435                                 return -EFAULT;
 436                 }
 437         } else
 438                 count = (old_hdr.result == 0) ? 0 : -EIO;
 439         sg_finish_rem_req(srp);
 440         return count;
 441 }
 442
 443 static ssize_t
 444 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
 445 {
 446         sg_io_hdr_t *hp = &srp->header;
 447         int err = 0;
 448         int len;
 449
 450         if (count < SZ_SG_IO_HDR) {
 451                 err = -EINVAL;
 452                 goto err_out;
 453         }
 454         hp->sb_len_wr = 0;
 455         if ((hp->mx_sb_len > 0) && hp->sbp) {
 456                 if ((CHECK_CONDITION & hp->masked_status) ||
 457                     (DRIVER_SENSE & hp->driver_status)) {
 458                         int sb_len = sizeof (dummy_cmdp->sr_sense_buffer);
 459                         sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
 460                         len = 8 + (int) srp->sense_b[7];        /* Additional sense length field */
 461                         len = (len > sb_len) ? sb_len : len;
 462                         if (copy_to_user(hp->sbp, srp->sense_b, len)) {
 463                                 err = -EFAULT;
 464                                 goto err_out;
 465                         }
 466                         hp->sb_len_wr = len;
 467                 }
 468         }
 469         if (hp->masked_status || hp->host_status || hp->driver_status)
 470                 hp->info |= SG_INFO_CHECK;
 471         if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
 472                 err = -EFAULT;
 473                 goto err_out;
 474         }
 475         err = sg_read_xfer(srp);
 476       err_out:
 477         sg_finish_rem_req(srp);
 478         return (0 == err) ? count : err;
 479 }
 480
 481 static ssize_t
 482 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
 483 {
 484         int mxsize, cmd_size, k;
 485         int input_size, blocking;
 486         unsigned char opcode;
 487         Sg_device *sdp;
 488         Sg_fd *sfp;
 489         Sg_request *srp;
 490         struct sg_header old_hdr;
 491         sg_io_hdr_t *hp;
 492         unsigned char cmnd[sizeof (dummy_cmdp->sr_cmnd)];
 493
 494         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 495                 return -ENXIO;
 496         SCSI_LOG_TIMEOUT(3, printk("sg_write: %s, count=%d\n",
 497                                    sdp->disk->disk_name, (int) count));
 498         if (sdp->detached)
 499                 return -ENODEV;
 500         if (!((filp->f_flags & O_NONBLOCK) ||
 501               scsi_block_when_processing_errors(sdp->device)))
 502                 return -ENXIO;
 503
 504         if (!access_ok(VERIFY_READ, buf, count))
 505                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 506         if (count < SZ_SG_HEADER)
 507                 return -EIO;
 508         if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
 509                 return -EFAULT;
 510         blocking = !(filp->f_flags & O_NONBLOCK);
 511         if (old_hdr.reply_len < 0)
 512                 return sg_new_write(sfp, buf, count, blocking, 0, NULL);
 513         if (count < (SZ_SG_HEADER + 6))
 514                 return -EIO;    /* The minimum scsi command length is 6 bytes. */
 515
 516         if (!(srp = sg_add_request(sfp))) {
 517                 SCSI_LOG_TIMEOUT(1, printk("sg_write: queue full\n"));
 518                 return -EDOM;
 519         }
 520         buf += SZ_SG_HEADER;
 521         __get_user(opcode, buf);
 522         if (sfp->next_cmd_len > 0) {
 523                 if (sfp->next_cmd_len > MAX_COMMAND_SIZE) {
 524                         SCSI_LOG_TIMEOUT(1, printk("sg_write: command length too long\n"));
 525                         sfp->next_cmd_len = 0;
 526                         sg_remove_request(sfp, srp);
 527                         return -EIO;
 528                 }
 529                 cmd_size = sfp->next_cmd_len;
 530                 sfp->next_cmd_len = 0;  /* reset so only this write() effected */
 531         } else {
 532                 cmd_size = COMMAND_SIZE(opcode);        /* based on SCSI command group */
 533                 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
 534                         cmd_size = 12;
 535         }
 536         SCSI_LOG_TIMEOUT(4, printk(
 537                 "sg_write:   scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
 538 /* Determine buffer size.  */
 539         input_size = count - cmd_size;
 540         mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
 541         mxsize -= SZ_SG_HEADER;
 542         input_size -= SZ_SG_HEADER;
 543         if (input_size < 0) {
 544                 sg_remove_request(sfp, srp);
 545                 return -EIO;    /* User did not pass enough bytes for this command. */
 546         }
 547         hp = &srp->header;
 548         hp->interface_id = '\0';        /* indicator of old interface tunnelled */
 549         hp->cmd_len = (unsigned char) cmd_size;
 550         hp->iovec_count = 0;
 551         hp->mx_sb_len = 0;
 552         if (input_size > 0)
 553                 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
 554                     SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
 555         else
 556                 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
 557         hp->dxfer_len = mxsize;
 558         hp->dxferp = (char __user *)buf + cmd_size;
 559         hp->sbp = NULL;
 560         hp->timeout = old_hdr.reply_len;        /* structure abuse ... */
 561         hp->flags = input_size; /* structure abuse ... */
 562         hp->pack_id = old_hdr.pack_id;
 563         hp->usr_ptr = NULL;
 564         if (__copy_from_user(cmnd, buf, cmd_size))
 565                 return -EFAULT;
 566         /*
 567          * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
 568          * but is is possible that the app intended SG_DXFER_TO_DEV, because there
 569          * is a non-zero input_size, so emit a warning.
 570          */
 571         if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV)
 572                 if (printk_ratelimit())
 573                         printk(KERN_WARNING
 574                                "sg_write: data in/out %d/%d bytes for SCSI command 0x%x--"
 575                                "guessing data in;\n" KERN_WARNING "   "
 576                                "program %s not setting count and/or reply_len properly\n",
 577                                old_hdr.reply_len - (int)SZ_SG_HEADER,
 578                                input_size, (unsigned int) cmnd[0],
 579                                current->comm);
 580         k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
 581         return (k < 0) ? k : count;
 582 }
 583
 584 static ssize_t
 585 sg_new_write(Sg_fd * sfp, const char __user *buf, size_t count,
 586              int blocking, int read_only, Sg_request ** o_srp)
 587 {
 588         int k;
 589         Sg_request *srp;
 590         sg_io_hdr_t *hp;
 591         unsigned char cmnd[sizeof (dummy_cmdp->sr_cmnd)];
 592         int timeout;
 593         unsigned long ul_timeout;
 594
 595         if (count < SZ_SG_IO_HDR)
 596                 return -EINVAL;
 597         if (!access_ok(VERIFY_READ, buf, count))
 598                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 599
 600         sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
 601         if (!(srp = sg_add_request(sfp))) {
 602                 SCSI_LOG_TIMEOUT(1, printk("sg_new_write: queue full\n"));
 603                 return -EDOM;
 604         }
 605         hp = &srp->header;
 606         if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
 607                 sg_remove_request(sfp, srp);
 608                 return -EFAULT;
 609         }
 610         if (hp->interface_id != 'S') {
 611                 sg_remove_request(sfp, srp);
 612                 return -ENOSYS;
 613         }
 614         if (hp->flags & SG_FLAG_MMAP_IO) {
 615                 if (hp->dxfer_len > sfp->reserve.bufflen) {
 616                         sg_remove_request(sfp, srp);
 617                         return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
 618                 }
 619                 if (hp->flags & SG_FLAG_DIRECT_IO) {
 620                         sg_remove_request(sfp, srp);
 621                         return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
 622                 }
 623                 if (sg_res_in_use(sfp)) {
 624                         sg_remove_request(sfp, srp);
 625                         return -EBUSY;  /* reserve buffer already being used */
 626                 }
 627         }
 628         ul_timeout = msecs_to_jiffies(srp->header.timeout);
 629         timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
 630         if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
 631                 sg_remove_request(sfp, srp);
 632                 return -EMSGSIZE;
 633         }
 634         if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
 635                 sg_remove_request(sfp, srp);
 636                 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 637         }
 638         if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
 639                 sg_remove_request(sfp, srp);
 640                 return -EFAULT;
 641         }
 642         if (read_only &&
 643             (!sg_allow_access(cmnd[0], sfp->parentdp->device->type))) {
 644                 sg_remove_request(sfp, srp);
 645                 return -EPERM;
 646         }
 647         k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
 648         if (k < 0)
 649                 return k;
 650         if (o_srp)
 651                 *o_srp = srp;
 652         return count;
 653 }
 654
 655 static int
 656 sg_common_write(Sg_fd * sfp, Sg_request * srp,
 657                 unsigned char *cmnd, int timeout, int blocking)
 658 {
 659         int k;
 660         Scsi_Request *SRpnt;
 661         Sg_device *sdp = sfp->parentdp;
 662         sg_io_hdr_t *hp = &srp->header;
 663         request_queue_t *q;
 664
 665         srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
 666         hp->status = 0;
 667         hp->masked_status = 0;
 668         hp->msg_status = 0;
 669         hp->info = 0;
 670         hp->host_status = 0;
 671         hp->driver_status = 0;
 672         hp->resid = 0;
 673         SCSI_LOG_TIMEOUT(4, printk("sg_common_write:  scsi opcode=0x%02x, cmd_size=%d\n",
 674                           (int) cmnd[0], (int) hp->cmd_len));
 675
 676         if ((k = sg_start_req(srp))) {
 677                 SCSI_LOG_TIMEOUT(1, printk("sg_write: start_req err=%d\n", k));
 678                 sg_finish_rem_req(srp);
 679                 return k;       /* probably out of space --> ENOMEM */
 680         }
 681         if ((k = sg_write_xfer(srp))) {
 682                 SCSI_LOG_TIMEOUT(1, printk("sg_write: write_xfer, bad address\n"));
 683                 sg_finish_rem_req(srp);
 684                 return k;
 685         }
 686         if (sdp->detached) {
 687                 sg_finish_rem_req(srp);
 688                 return -ENODEV;
 689         }
 690         SRpnt = scsi_allocate_request(sdp->device, GFP_ATOMIC);
 691         if (SRpnt == NULL) {
 692                 SCSI_LOG_TIMEOUT(1, printk("sg_write: no mem\n"));
 693                 sg_finish_rem_req(srp);
 694                 return -ENOMEM;
 695         }
 696
 697         srp->my_cmdp = SRpnt;
 698         q = SRpnt->sr_device->request_queue;
 699         SRpnt->sr_request->rq_disk = sdp->disk;
 700         SRpnt->sr_sense_buffer[0] = 0;
 701         SRpnt->sr_cmd_len = hp->cmd_len;
 702         SRpnt->sr_use_sg = srp->data.k_use_sg;
 703         SRpnt->sr_sglist_len = srp->data.sglist_len;
 704         SRpnt->sr_bufflen = srp->data.bufflen;
 705         SRpnt->sr_underflow = 0;
 706         SRpnt->sr_buffer = srp->data.buffer;
 707         switch (hp->dxfer_direction) {
 708         case SG_DXFER_TO_FROM_DEV:
 709         case SG_DXFER_FROM_DEV:
 710                 SRpnt->sr_data_direction = SCSI_DATA_READ;
 711                 break;
 712         case SG_DXFER_TO_DEV:
 713                 SRpnt->sr_data_direction = SCSI_DATA_WRITE;
 714                 break;
 715         case SG_DXFER_UNKNOWN:
 716                 SRpnt->sr_data_direction = SCSI_DATA_UNKNOWN;
 717                 break;
 718         default:
 719                 SRpnt->sr_data_direction = SCSI_DATA_NONE;
 720                 break;
 721         }
 722         SRpnt->upper_private_data = srp;
 723         srp->data.k_use_sg = 0;
 724         srp->data.sglist_len = 0;
 725         srp->data.bufflen = 0;
 726         srp->data.buffer = NULL;
 727         hp->duration = jiffies; /* unit jiffies now, millisecs after done */
 728 /* Now send everything of to mid-level. The next time we hear about this
 729    packet is when sg_cmd_done() is called (i.e. a callback). */
 730         scsi_do_req(SRpnt, (void *) cmnd,
 731                     (void *) SRpnt->sr_buffer, hp->dxfer_len,
 732                     sg_cmd_done, timeout, SG_DEFAULT_RETRIES);
 733         /* dxfer_len overwrites SRpnt->sr_bufflen, hence need for b_malloc_len */
 734         return 0;
 735 }
 736
 737 static int
 738 sg_srp_done(Sg_request *srp, Sg_fd *sfp)
 739 {
 740         unsigned long iflags;
 741         int done;
 742
 743         read_lock_irqsave(&sfp->rq_list_lock, iflags);
 744         done = srp->done;
 745         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 746         return done;
 747 }
 748
 749 static int
 750 sg_ioctl(struct inode *inode, struct file *filp,
 751          unsigned int cmd_in, unsigned long arg)
 752 {
 753         void __user *p = (void __user *)arg;
 754         int __user *ip = p;
 755         int result, val, read_only;
 756         Sg_device *sdp;
 757         Sg_fd *sfp;
 758         Sg_request *srp;
 759         unsigned long iflags;
 760
 761         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 762                 return -ENXIO;
 763         SCSI_LOG_TIMEOUT(3, printk("sg_ioctl: %s, cmd=0x%x\n",
 764                                    sdp->disk->disk_name, (int) cmd_in));
 765         read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
 766
 767         switch (cmd_in) {
 768         case SG_IO:
 769                 {
 770                         int blocking = 1;       /* ignore O_NONBLOCK flag */
 771
 772                         if (sdp->detached)
 773                                 return -ENODEV;
 774                         if (!scsi_block_when_processing_errors(sdp->device))
 775                                 return -ENXIO;
 776                         if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
 777                                 return -EFAULT;
 778                         result =
 779                             sg_new_write(sfp, p, SZ_SG_IO_HDR,
 780                                          blocking, read_only, &srp);
 781                         if (result < 0)
 782                                 return result;
 783                         srp->sg_io_owned = 1;
 784                         while (1) {
 785                                 result = 0;     /* following macro to beat race condition */
 786                                 __wait_event_interruptible(sfp->read_wait,
 787                                         (sdp->detached || sfp->closed || sg_srp_done(srp, sfp)),
 788                                                            result);
 789                                 if (sdp->detached)
 790                                         return -ENODEV;
 791                                 if (sfp->closed)
 792                                         return 0;       /* request packet dropped already */
 793                                 if (0 == result)
 794                                         break;
 795                                 srp->orphan = 1;
 796                                 return result;  /* -ERESTARTSYS because signal hit process */
 797                         }
 798                         write_lock_irqsave(&sfp->rq_list_lock, iflags);
 799                         srp->done = 2;
 800                         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 801                         result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
 802                         return (result < 0) ? result : 0;
 803                 }
 804         case SG_SET_TIMEOUT:
 805                 result = get_user(val, ip);
 806                 if (result)
 807                         return result;
 808                 if (val < 0)
 809                         return -EIO;
 810                 if (val >= MULDIV (INT_MAX, USER_HZ, HZ))
 811                     val = MULDIV (INT_MAX, USER_HZ, HZ);
 812                 sfp->timeout_user = val;
 813                 sfp->timeout = MULDIV (val, HZ, USER_HZ);
 814
 815                 return 0;
 816         case SG_GET_TIMEOUT:    /* N.B. User receives timeout as return value */
 817                                 /* strange ..., for backward compatibility */
 818                 return sfp->timeout_user;
 819         case SG_SET_FORCE_LOW_DMA:
 820                 result = get_user(val, ip);
 821                 if (result)
 822                         return result;
 823                 if (val) {
 824                         sfp->low_dma = 1;
 825                         if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
 826                                 val = (int) sfp->reserve.bufflen;
 827                                 sg_remove_scat(&sfp->reserve);
 828                                 sg_build_reserve(sfp, val);
 829                         }
 830                 } else {
 831                         if (sdp->detached)
 832                                 return -ENODEV;
 833                         sfp->low_dma = sdp->device->host->unchecked_isa_dma;
 834                 }
 835                 return 0;
 836         case SG_GET_LOW_DMA:
 837                 return put_user((int) sfp->low_dma, ip);
 838         case SG_GET_SCSI_ID:
 839                 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
 840                         return -EFAULT;
 841                 else {
 842                         sg_scsi_id_t __user *sg_idp = p;
 843
 844                         if (sdp->detached)
 845                                 return -ENODEV;
 846                         __put_user((int) sdp->device->host->host_no,
 847                                    &sg_idp->host_no);
 848                         __put_user((int) sdp->device->channel,
 849                                    &sg_idp->channel);
 850                         __put_user((int) sdp->device->id, &sg_idp->scsi_id);
 851                         __put_user((int) sdp->device->lun, &sg_idp->lun);
 852                         __put_user((int) sdp->device->type, &sg_idp->scsi_type);
 853                         __put_user((short) sdp->device->host->cmd_per_lun,
 854                                    &sg_idp->h_cmd_per_lun);
 855                         __put_user((short) sdp->device->queue_depth,
 856                                    &sg_idp->d_queue_depth);
 857                         __put_user(0, &sg_idp->unused[0]);
 858                         __put_user(0, &sg_idp->unused[1]);
 859                         return 0;
 860                 }
 861         case SG_SET_FORCE_PACK_ID:
 862                 result = get_user(val, ip);
 863                 if (result)
 864                         return result;
 865                 sfp->force_packid = val ? 1 : 0;
 866                 return 0;
 867         case SG_GET_PACK_ID:
 868                 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
 869                         return -EFAULT;
 870                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 871                 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
 872                         if ((1 == srp->done) && (!srp->sg_io_owned)) {
 873                                 read_unlock_irqrestore(&sfp->rq_list_lock,
 874                                                        iflags);
 875                                 __put_user(srp->header.pack_id, ip);
 876                                 return 0;
 877                         }
 878                 }
 879                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 880                 __put_user(-1, ip);
 881                 return 0;
 882         case SG_GET_NUM_WAITING:
 883                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 884                 for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) {
 885                         if ((1 == srp->done) && (!srp->sg_io_owned))
 886                                 ++val;
 887                 }
 888                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 889                 return put_user(val, ip);
 890         case SG_GET_SG_TABLESIZE:
 891                 return put_user(sdp->sg_tablesize, ip);
 892         case SG_SET_RESERVED_SIZE:
 893                 result = get_user(val, ip);
 894                 if (result)
 895                         return result;
 896                 if (val < 0)
 897                         return -EINVAL;
 898                 if (val != sfp->reserve.bufflen) {
 899                         if (sg_res_in_use(sfp) || sfp->mmap_called)
 900                                 return -EBUSY;
 901                         sg_remove_scat(&sfp->reserve);
 902                         sg_build_reserve(sfp, val);
 903                 }
 904                 return 0;
 905         case SG_GET_RESERVED_SIZE:
 906                 val = (int) sfp->reserve.bufflen;
 907                 return put_user(val, ip);
 908         case SG_SET_COMMAND_Q:
 909                 result = get_user(val, ip);
 910                 if (result)
 911                         return result;
 912                 sfp->cmd_q = val ? 1 : 0;
 913                 return 0;
 914         case SG_GET_COMMAND_Q:
 915                 return put_user((int) sfp->cmd_q, ip);
 916         case SG_SET_KEEP_ORPHAN:
 917                 result = get_user(val, ip);
 918                 if (result)
 919                         return result;
 920                 sfp->keep_orphan = val;
 921                 return 0;
 922         case SG_GET_KEEP_ORPHAN:
 923                 return put_user((int) sfp->keep_orphan, ip);
 924         case SG_NEXT_CMD_LEN:
 925                 result = get_user(val, ip);
 926                 if (result)
 927                         return result;
 928                 sfp->next_cmd_len = (val > 0) ? val : 0;
 929                 return 0;
 930         case SG_GET_VERSION_NUM:
 931                 return put_user(sg_version_num, ip);
 932         case SG_GET_ACCESS_COUNT:
 933                 /* faked - we don't have a real access count anymore */
 934                 val = (sdp->device ? 1 : 0);
 935                 return put_user(val, ip);
 936         case SG_GET_REQUEST_TABLE:
 937                 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
 938                         return -EFAULT;
 939                 else {
 940                         sg_req_info_t rinfo[SG_MAX_QUEUE];
 941                         Sg_request *srp;
 942                         read_lock_irqsave(&sfp->rq_list_lock, iflags);
 943                         for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE;
 944                              ++val, srp = srp ? srp->nextrp : srp) {
 945                                 memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
 946                                 if (srp) {
 947                                         rinfo[val].req_state = srp->done + 1;
 948                                         rinfo[val].problem =
 949                                             srp->header.masked_status &
 950                                             srp->header.host_status &
 951                                             srp->header.driver_status;
 952                                         rinfo[val].duration =
 953                                             srp->done ? srp->header.duration :
 954                                             jiffies_to_msecs(
 955                                                 jiffies - srp->header.duration);
 956                                         rinfo[val].orphan = srp->orphan;
 957                                         rinfo[val].sg_io_owned = srp->sg_io_owned;
 958                                         rinfo[val].pack_id = srp->header.pack_id;
 959                                         rinfo[val].usr_ptr = srp->header.usr_ptr;
 960                                 }
 961                         }
 962                         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 963                         return (__copy_to_user(p, rinfo,
 964                                 SZ_SG_REQ_INFO * SG_MAX_QUEUE) ? -EFAULT : 0);
 965                 }
 966         case SG_EMULATED_HOST:
 967                 if (sdp->detached)
 968                         return -ENODEV;
 969                 return put_user(sdp->device->host->hostt->emulated, ip);
 970         case SG_SCSI_RESET:
 971                 if (sdp->detached)
 972                         return -ENODEV;
 973                 if (filp->f_flags & O_NONBLOCK) {
 974                         if (test_bit(SHOST_RECOVERY,
 975                                      &sdp->device->host->shost_state))
 976                                 return -EBUSY;
 977                 } else if (!scsi_block_when_processing_errors(sdp->device))
 978                         return -EBUSY;
 979                 result = get_user(val, ip);
 980                 if (result)
 981                         return result;
 982                 if (SG_SCSI_RESET_NOTHING == val)
 983                         return 0;
 984                 switch (val) {
 985                 case SG_SCSI_RESET_DEVICE:
 986                         val = SCSI_TRY_RESET_DEVICE;
 987                         break;
 988                 case SG_SCSI_RESET_BUS:
 989                         val = SCSI_TRY_RESET_BUS;
 990                         break;
 991                 case SG_SCSI_RESET_HOST:
 992                         val = SCSI_TRY_RESET_HOST;
 993                         break;
 994                 default:
 995                         return -EINVAL;
 996                 }
 997                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
 998                         return -EACCES;
 999                 return (scsi_reset_provider(sdp->device, val) ==
1000                         SUCCESS) ? 0 : -EIO;
1001         case SCSI_IOCTL_SEND_COMMAND:
1002                 if (sdp->detached)
1003                         return -ENODEV;
1004                 if (read_only) {
1005                         unsigned char opcode = WRITE_6;
1006                         Scsi_Ioctl_Command __user *siocp = p;
1007
1008                         if (copy_from_user(&opcode, siocp->data, 1))
1009                                 return -EFAULT;
1010                         if (!sg_allow_access(opcode, sdp->device->type))
1011                                 return -EPERM;
1012                 }
1013                 return scsi_ioctl_send_command(sdp->device, p);
1014         case SG_SET_DEBUG:
1015                 result = get_user(val, ip);
1016                 if (result)
1017                         return result;
1018                 sdp->sgdebug = (char) val;
1019                 return 0;
1020         case SCSI_IOCTL_GET_IDLUN:
1021         case SCSI_IOCTL_GET_BUS_NUMBER:
1022         case SCSI_IOCTL_PROBE_HOST:
1023         case SG_GET_TRANSFORM:
1024                 if (sdp->detached)
1025                         return -ENODEV;
1026                 return scsi_ioctl(sdp->device, cmd_in, p);
1027         default:
1028                 if (read_only)
1029                         return -EPERM;  /* don't know so take safe approach */
1030                 return scsi_ioctl(sdp->device, cmd_in, p);
1031         }
1032 }
1033
1034 #ifdef CONFIG_COMPAT
1035 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1036 {
1037         Sg_device *sdp;
1038         Sg_fd *sfp;
1039         struct scsi_device *sdev;
1040
1041         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1042                 return -ENXIO;
1043
1044         sdev = sdp->device;
1045         if (sdev->host->hostt->compat_ioctl) {
1046                 int ret;
1047
1048                 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1049
1050                 return ret;
1051         }
1052
1053         return -ENOIOCTLCMD;
1054 }
1055 #endif
1056
1057 static unsigned int
1058 sg_poll(struct file *filp, poll_table * wait)
1059 {
1060         unsigned int res = 0;
1061         Sg_device *sdp;
1062         Sg_fd *sfp;
1063         Sg_request *srp;
1064         int count = 0;
1065         unsigned long iflags;
1066
1067         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))
1068             || sfp->closed)
1069                 return POLLERR;
1070         poll_wait(filp, &sfp->read_wait, wait);
1071         read_lock_irqsave(&sfp->rq_list_lock, iflags);
1072         for (srp = sfp->headrp; srp; srp = srp->nextrp) {
1073                 /* if any read waiting, flag it */
1074                 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1075                         res = POLLIN | POLLRDNORM;
1076                 ++count;
1077         }
1078         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1079
1080         if (sdp->detached)
1081                 res |= POLLHUP;
1082         else if (!sfp->cmd_q) {
1083                 if (0 == count)
1084                         res |= POLLOUT | POLLWRNORM;
1085         } else if (count < SG_MAX_QUEUE)
1086                 res |= POLLOUT | POLLWRNORM;
1087         SCSI_LOG_TIMEOUT(3, printk("sg_poll: %s, res=0x%x\n",
1088                                    sdp->disk->disk_name, (int) res));
1089         return res;
1090 }
1091
1092 static int
1093 sg_fasync(int fd, struct file *filp, int mode)
1094 {
1095         int retval;
1096         Sg_device *sdp;
1097         Sg_fd *sfp;
1098
1099         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1100                 return -ENXIO;
1101         SCSI_LOG_TIMEOUT(3, printk("sg_fasync: %s, mode=%d\n",
1102                                    sdp->disk->disk_name, mode));
1103
1104         retval = fasync_helper(fd, filp, mode, &sfp->async_qp);
1105         return (retval < 0) ? retval : 0;
1106 }
1107
1108 static inline unsigned char *
1109 sg_scatg2virt(const struct scatterlist *sclp)
1110 {
1111         return (sclp && sclp->page) ?
1112             (unsigned char *) page_address(sclp->page) + sclp->offset : NULL;
1113 }
1114
1115 /* When startFinish==1 increments page counts for pages other than the
1116    first of scatter gather elements obtained from __get_free_pages().
1117    When startFinish==0 decrements ... */
1118 static void
1119 sg_rb_correct4mmap(Sg_scatter_hold * rsv_schp, int startFinish)
1120 {
1121         void *page_ptr;
1122         struct page *page;
1123         int k, m;
1124
1125         SCSI_LOG_TIMEOUT(3, printk("sg_rb_correct4mmap: startFinish=%d, scatg=%d\n",
1126                                    startFinish, rsv_schp->k_use_sg));
1127         /* N.B. correction _not_ applied to base page of each allocation */
1128         if (rsv_schp->k_use_sg) {       /* reserve buffer is a scatter gather list */
1129                 struct scatterlist *sclp = rsv_schp->buffer;
1130
1131                 for (k = 0; k < rsv_schp->k_use_sg; ++k, ++sclp) {
1132                         for (m = PAGE_SIZE; m < sclp->length; m += PAGE_SIZE) {
1133                                 page_ptr = sg_scatg2virt(sclp) + m;
1134                                 page = virt_to_page(page_ptr);
1135                                 if (startFinish)
1136                                         get_page(page);
1137                                 else {
1138                                         if (page_count(page) > 0)
1139                                                 __put_page(page);
1140                                 }
1141                         }
1142                 }
1143         } else {                /* reserve buffer is just a single allocation */
1144                 for (m = PAGE_SIZE; m < rsv_schp->bufflen; m += PAGE_SIZE) {
1145                         page_ptr = (unsigned char *) rsv_schp->buffer + m;
1146                         page = virt_to_page(page_ptr);
1147                         if (startFinish)
1148                                 get_page(page);
1149                         else {
1150                                 if (page_count(page) > 0)
1151                                         __put_page(page);
1152                         }
1153                 }
1154         }
1155 }
1156
1157 static struct page *
1158 sg_vma_nopage(struct vm_area_struct *vma, unsigned long addr, int *type)
1159 {
1160         Sg_fd *sfp;
1161         struct page *page = NOPAGE_SIGBUS;
1162         void *page_ptr = NULL;
1163         unsigned long offset;
1164         Sg_scatter_hold *rsv_schp;
1165
1166         if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1167                 return page;
1168         rsv_schp = &sfp->reserve;
1169         offset = addr - vma->vm_start;
1170         if (offset >= rsv_schp->bufflen)
1171                 return page;
1172         SCSI_LOG_TIMEOUT(3, printk("sg_vma_nopage: offset=%lu, scatg=%d\n",
1173                                    offset, rsv_schp->k_use_sg));
1174         if (rsv_schp->k_use_sg) {       /* reserve buffer is a scatter gather list */
1175                 int k;
1176                 unsigned long sa = vma->vm_start;
1177                 unsigned long len;
1178                 struct scatterlist *sclp = rsv_schp->buffer;
1179
1180                 for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
1181                      ++k, ++sclp) {
1182                         len = vma->vm_end - sa;
1183                         len = (len < sclp->length) ? len : sclp->length;
1184                         if (offset < len) {
1185                                 page_ptr = sg_scatg2virt(sclp) + offset;
1186                                 page = virt_to_page(page_ptr);
1187                                 get_page(page); /* increment page count */
1188                                 break;
1189                         }
1190                         sa += len;
1191                         offset -= len;
1192                 }
1193         } else {                /* reserve buffer is just a single allocation */
1194                 page_ptr = (unsigned char *) rsv_schp->buffer + offset;
1195                 page = virt_to_page(page_ptr);
1196                 get_page(page); /* increment page count */
1197         }
1198         if (type)
1199                 *type = VM_FAULT_MINOR;
1200         return page;
1201 }
1202
1203 static struct vm_operations_struct sg_mmap_vm_ops = {
1204         .nopage = sg_vma_nopage,
1205 };
1206
1207 static int
1208 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1209 {
1210         Sg_fd *sfp;
1211         unsigned long req_sz = vma->vm_end - vma->vm_start;
1212         Sg_scatter_hold *rsv_schp;
1213
1214         if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1215                 return -ENXIO;
1216         SCSI_LOG_TIMEOUT(3, printk("sg_mmap starting, vm_start=%p, len=%d\n",
1217                                    (void *) vma->vm_start, (int) req_sz));
1218         if (vma->vm_pgoff)
1219                 return -EINVAL; /* want no offset */
1220         rsv_schp = &sfp->reserve;
1221         if (req_sz > rsv_schp->bufflen)
1222                 return -ENOMEM; /* cannot map more than reserved buffer */
1223
1224         if (rsv_schp->k_use_sg) { /* reserve buffer is a scatter gather list */
1225                 int k;
1226                 unsigned long sa = vma->vm_start;
1227                 unsigned long len;
1228                 struct scatterlist *sclp = rsv_schp->buffer;
1229
1230                 for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
1231                      ++k, ++sclp) {
1232                         if (0 != sclp->offset)
1233                                 return -EFAULT; /* non page aligned memory ?? */
1234                         len = vma->vm_end - sa;
1235                         len = (len < sclp->length) ? len : sclp->length;
1236                         sa += len;
1237                 }
1238         } else {        /* reserve buffer is just a single allocation */
1239                 if ((unsigned long) rsv_schp->buffer & (PAGE_SIZE - 1))
1240                         return -EFAULT; /* non page aligned memory ?? */
1241         }
1242         if (0 == sfp->mmap_called) {
1243                 sg_rb_correct4mmap(rsv_schp, 1);        /* do only once per fd lifetime */
1244                 sfp->mmap_called = 1;
1245         }
1246         vma->vm_flags |= (VM_RESERVED | VM_IO);
1247         vma->vm_private_data = sfp;
1248         vma->vm_ops = &sg_mmap_vm_ops;
1249         return 0;
1250 }
1251
1252 /* This function is a "bottom half" handler that is called by the
1253  * mid level when a command is completed (or has failed). */
1254 static void
1255 sg_cmd_done(Scsi_Cmnd * SCpnt)
1256 {
1257         Scsi_Request *SRpnt = NULL;
1258         Sg_device *sdp = NULL;
1259         Sg_fd *sfp;
1260         Sg_request *srp = NULL;
1261         unsigned long iflags;
1262
1263         if (SCpnt && (SRpnt = SCpnt->sc_request))
1264                 srp = (Sg_request *) SRpnt->upper_private_data;
1265         if (NULL == srp) {
1266                 printk(KERN_ERR "sg_cmd_done: NULL request\n");
1267                 if (SRpnt)
1268                         scsi_release_request(SRpnt);
1269                 return;
1270         }
1271         sfp = srp->parentfp;
1272         if (sfp)
1273                 sdp = sfp->parentdp;
1274         if ((NULL == sdp) || sdp->detached) {
1275                 printk(KERN_INFO "sg_cmd_done: device detached\n");
1276                 scsi_release_request(SRpnt);
1277                 return;
1278         }
1279
1280         /* First transfer ownership of data buffers to sg_device object. */
1281         srp->data.k_use_sg = SRpnt->sr_use_sg;
1282         srp->data.sglist_len = SRpnt->sr_sglist_len;
1283         srp->data.bufflen = SRpnt->sr_bufflen;
1284         srp->data.buffer = SRpnt->sr_buffer;
1285         /* now clear out request structure */
1286         SRpnt->sr_use_sg = 0;
1287         SRpnt->sr_sglist_len = 0;
1288         SRpnt->sr_bufflen = 0;
1289         SRpnt->sr_buffer = NULL;
1290         SRpnt->sr_underflow = 0;
1291         SRpnt->sr_request->rq_disk = NULL; /* "sg" _disowns_ request blk */
1292
1293         srp->my_cmdp = NULL;
1294
1295         SCSI_LOG_TIMEOUT(4, printk("sg_cmd_done: %s, pack_id=%d, res=0x%x\n",
1296                 sdp->disk->disk_name, srp->header.pack_id, (int) SRpnt->sr_result));
1297         srp->header.resid = SCpnt->resid;
1298         /* N.B. unit of duration changes here from jiffies to millisecs */
1299         srp->header.duration =
1300             jiffies_to_msecs(jiffies - srp->header.duration);
1301         if (0 != SRpnt->sr_result) {
1302                 struct scsi_sense_hdr sshdr;
1303
1304                 memcpy(srp->sense_b, SRpnt->sr_sense_buffer,
1305                        sizeof (srp->sense_b));
1306                 srp->header.status = 0xff & SRpnt->sr_result;
1307                 srp->header.masked_status = status_byte(SRpnt->sr_result);
1308                 srp->header.msg_status = msg_byte(SRpnt->sr_result);
1309                 srp->header.host_status = host_byte(SRpnt->sr_result);
1310                 srp->header.driver_status = driver_byte(SRpnt->sr_result);
1311                 if ((sdp->sgdebug > 0) &&
1312                     ((CHECK_CONDITION == srp->header.masked_status) ||
1313                      (COMMAND_TERMINATED == srp->header.masked_status)))
1314                         print_req_sense("sg_cmd_done", SRpnt);
1315
1316                 /* Following if statement is a patch supplied by Eric Youngdale */
1317                 if (driver_byte(SRpnt->sr_result) != 0
1318                     && scsi_command_normalize_sense(SCpnt, &sshdr)
1319                     && !scsi_sense_is_deferred(&sshdr)
1320                     && sshdr.sense_key == UNIT_ATTENTION
1321                     && sdp->device->removable) {
1322                         /* Detected possible disc change. Set the bit - this */
1323                         /* may be used if there are filesystems using this device */
1324                         sdp->device->changed = 1;
1325                 }
1326         }
1327         /* Rely on write phase to clean out srp status values, so no "else" */
1328
1329         scsi_release_request(SRpnt);
1330         SRpnt = NULL;
1331         if (sfp->closed) {      /* whoops this fd already released, cleanup */
1332                 SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, freeing ...\n"));
1333                 sg_finish_rem_req(srp);
1334                 srp = NULL;
1335                 if (NULL == sfp->headrp) {
1336                         SCSI_LOG_TIMEOUT(1, printk("sg...bh: already closed, final cleanup\n"));
1337                         if (0 == sg_remove_sfp(sdp, sfp)) {     /* device still present */
1338                                 scsi_device_put(sdp->device);
1339                         }
1340                         sfp = NULL;
1341                 }
1342         } else if (srp && srp->orphan) {
1343                 if (sfp->keep_orphan)
1344                         srp->sg_io_owned = 0;
1345                 else {
1346                         sg_finish_rem_req(srp);
1347                         srp = NULL;
1348                 }
1349         }
1350         if (sfp && srp) {
1351                 /* Now wake up any sg_read() that is waiting for this packet. */
1352                 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1353                 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1354                 srp->done = 1;
1355                 wake_up_interruptible(&sfp->read_wait);
1356                 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1357         }
1358 }
1359
1360 static struct file_operations sg_fops = {
1361         .owner = THIS_MODULE,
1362         .read = sg_read,
1363         .write = sg_write,
1364         .poll = sg_poll,
1365         .ioctl = sg_ioctl,
1366 #ifdef CONFIG_COMPAT
1367         .compat_ioctl = sg_compat_ioctl,
1368 #endif
1369         .open = sg_open,
1370         .mmap = sg_mmap,
1371         .release = sg_release,
1372         .fasync = sg_fasync,
1373 };
1374
1375 static struct class_simple * sg_sysfs_class;
1376
1377 static int sg_sysfs_valid = 0;
1378
1379 static int sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1380 {
1381         Sg_device *sdp;
1382         unsigned long iflags;
1383         void *old_sg_dev_arr = NULL;
1384         int k, error;
1385
1386         sdp = kmalloc(sizeof(Sg_device), GFP_KERNEL);
1387         if (!sdp) {
1388                 printk(KERN_WARNING "kmalloc Sg_device failure\n");
1389                 return -ENOMEM;
1390         }
1391
1392         write_lock_irqsave(&sg_dev_arr_lock, iflags);
1393         if (unlikely(sg_nr_dev >= sg_dev_max)) {        /* try to resize */
1394                 Sg_device **tmp_da;
1395                 int tmp_dev_max = sg_nr_dev + SG_DEV_ARR_LUMP;
1396                 write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1397
1398                 tmp_da = kmalloc(tmp_dev_max * sizeof(Sg_device *), GFP_KERNEL);
1399                 if (unlikely(!tmp_da))
1400                         goto expand_failed;
1401
1402                 write_lock_irqsave(&sg_dev_arr_lock, iflags);
1403                 memset(tmp_da, 0, tmp_dev_max * sizeof(Sg_device *));
1404                 memcpy(tmp_da, sg_dev_arr, sg_dev_max * sizeof(Sg_device *));
1405                 old_sg_dev_arr = sg_dev_arr;
1406                 sg_dev_arr = tmp_da;
1407                 sg_dev_max = tmp_dev_max;
1408         }
1409
1410         for (k = 0; k < sg_dev_max; k++)
1411                 if (!sg_dev_arr[k])
1412                         break;
1413         if (unlikely(k >= SG_MAX_DEVS))
1414                 goto overflow;
1415
1416         memset(sdp, 0, sizeof(*sdp));
1417         SCSI_LOG_TIMEOUT(3, printk("sg_alloc: dev=%d \n", k));
1418         sprintf(disk->disk_name, "sg%d", k);
1419         disk->first_minor = k;
1420         sdp->disk = disk;
1421         sdp->device = scsidp;
1422         init_waitqueue_head(&sdp->o_excl_wait);
1423         sdp->sg_tablesize = scsidp->host ? scsidp->host->sg_tablesize : 0;
1424
1425         sg_nr_dev++;
1426         sg_dev_arr[k] = sdp;
1427         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1428         error = k;
1429
1430  out:
1431         if (error < 0)
1432                 kfree(sdp);
1433         kfree(old_sg_dev_arr);
1434         return error;
1435
1436  expand_failed:
1437         printk(KERN_WARNING "sg_alloc: device array cannot be resized\n");
1438         error = -ENOMEM;
1439         goto out;
1440
1441  overflow:
1442         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1443         printk(KERN_WARNING
1444                "Unable to attach sg device <%d, %d, %d, %d> type=%d, minor "
1445                "number exceeds %d\n", scsidp->host->host_no, scsidp->channel,
1446                scsidp->id, scsidp->lun, scsidp->type, SG_MAX_DEVS - 1);
1447         error = -ENODEV;
1448         goto out;
1449 }
1450
1451 static int
1452 sg_add(struct class_device *cl_dev)
1453 {
1454         struct scsi_device *scsidp = to_scsi_device(cl_dev->dev);
1455         struct gendisk *disk;
1456         Sg_device *sdp = NULL;
1457         struct cdev * cdev = NULL;
1458         int error, k;
1459
1460         disk = alloc_disk(1);
1461         if (!disk) {
1462                 printk(KERN_WARNING "alloc_disk failed\n");
1463                 return -ENOMEM;
1464         }
1465         disk->major = SCSI_GENERIC_MAJOR;
1466
1467         error = -ENOMEM;
1468         cdev = cdev_alloc();
1469         if (!cdev) {
1470                 printk(KERN_WARNING "cdev_alloc failed\n");
1471                 goto out;
1472         }
1473         cdev->owner = THIS_MODULE;
1474         cdev->ops = &sg_fops;
1475
1476         error = sg_alloc(disk, scsidp);
1477         if (error < 0) {
1478                 printk(KERN_WARNING "sg_alloc failed\n");
1479                 goto out;
1480         }
1481         k = error;
1482         sdp = sg_dev_arr[k];
1483
1484         devfs_mk_cdev(MKDEV(SCSI_GENERIC_MAJOR, k),
1485                         S_IFCHR | S_IRUSR | S_IWUSR | S_IRGRP,
1486                         "%s/generic", scsidp->devfs_name);
1487         error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, k), 1);
1488         if (error) {
1489                 devfs_remove("%s/generic", scsidp->devfs_name);
1490                 goto out;
1491         }
1492         sdp->cdev = cdev;
1493         if (sg_sysfs_valid) {
1494                 struct class_device * sg_class_member;
1495
1496                 sg_class_member = class_simple_device_add(sg_sysfs_class,
1497                                 MKDEV(SCSI_GENERIC_MAJOR, k),
1498                                 cl_dev->dev, "%s",
1499                                 disk->disk_name);
1500                 if (IS_ERR(sg_class_member))
1501                         printk(KERN_WARNING "sg_add: "
1502                                 "class_simple_device_add failed\n");
1503                 class_set_devdata(sg_class_member, sdp);
1504                 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1505                                           &sg_class_member->kobj, "generic");
1506                 if (error)
1507                         printk(KERN_ERR "sg_add: unable to make symlink "
1508                                         "'generic' back to sg%d\n", k);
1509         } else
1510                 printk(KERN_WARNING "sg_add: sg_sys INvalid\n");
1511
1512         printk(KERN_NOTICE
1513                "Attached scsi generic sg%d at scsi%d, channel"
1514                " %d, id %d, lun %d,  type %d\n", k,
1515                scsidp->host->host_no, scsidp->channel, scsidp->id,
1516                scsidp->lun, scsidp->type);
1517
1518         return 0;
1519
1520 out:
1521         put_disk(disk);
1522         if (cdev)
1523                 cdev_del(cdev);
1524         return error;
1525 }
1526
1527 static void
1528 sg_remove(struct class_device *cl_dev)
1529 {
1530         struct scsi_device *scsidp = to_scsi_device(cl_dev->dev);
1531         Sg_device *sdp = NULL;
1532         unsigned long iflags;
1533         Sg_fd *sfp;
1534         Sg_fd *tsfp;
1535         Sg_request *srp;
1536         Sg_request *tsrp;
1537         int k, delay;
1538
1539         if (NULL == sg_dev_arr)
1540                 return;
1541         delay = 0;
1542         write_lock_irqsave(&sg_dev_arr_lock, iflags);
1543         for (k = 0; k < sg_dev_max; k++) {
1544                 sdp = sg_dev_arr[k];
1545                 if ((NULL == sdp) || (sdp->device != scsidp))
1546                         continue;       /* dirty but lowers nesting */
1547                 if (sdp->headfp) {
1548                         sdp->detached = 1;
1549                         for (sfp = sdp->headfp; sfp; sfp = tsfp) {
1550                                 tsfp = sfp->nextfp;
1551                                 for (srp = sfp->headrp; srp; srp = tsrp) {
1552                                         tsrp = srp->nextrp;
1553                                         if (sfp->closed || (0 == sg_srp_done(srp, sfp)))
1554                                                 sg_finish_rem_req(srp);
1555                                 }
1556                                 if (sfp->closed) {
1557                                         scsi_device_put(sdp->device);
1558                                         __sg_remove_sfp(sdp, sfp);
1559                                 } else {
1560                                         delay = 1;
1561                                         wake_up_interruptible(&sfp->read_wait);
1562                                         kill_fasync(&sfp->async_qp, SIGPOLL,
1563                                                     POLL_HUP);
1564                                 }
1565                         }
1566                         SCSI_LOG_TIMEOUT(3, printk("sg_detach: dev=%d, dirty\n", k));
1567                         if (NULL == sdp->headfp) {
1568                                 sg_dev_arr[k] = NULL;
1569                         }
1570                 } else {        /* nothing active, simple case */
1571                         SCSI_LOG_TIMEOUT(3, printk("sg_detach: dev=%d\n", k));
1572                         sg_dev_arr[k] = NULL;
1573                 }
1574                 sg_nr_dev--;
1575                 break;
1576         }
1577         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1578
1579         if (sdp) {
1580                 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1581                 class_simple_device_remove(MKDEV(SCSI_GENERIC_MAJOR, k));
1582                 cdev_del(sdp->cdev);
1583                 sdp->cdev = NULL;
1584                 devfs_remove("%s/generic", scsidp->devfs_name);
1585                 put_disk(sdp->disk);
1586                 sdp->disk = NULL;
1587                 if (NULL == sdp->headfp)
1588                         kfree((char *) sdp);
1589         }
1590
1591         if (delay)
1592                 msleep(10);     /* dirty detach so delay device destruction */
1593 }
1594
1595 /* Set 'perm' (4th argument) to 0 to disable module_param's definition
1596  * of sysfs parameters (which module_param doesn't yet support).
1597  * Sysfs parameters defined explicitly below.
1598  */
1599 module_param_named(def_reserved_size, def_reserved_size, int, S_IRUGO);
1600 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1601
1602 MODULE_AUTHOR("Douglas Gilbert");
1603 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1604 MODULE_LICENSE("GPL");
1605 MODULE_VERSION(SG_VERSION_STR);
1606
1607 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1608 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1609
1610 static int __init
1611 init_sg(void)
1612 {
1613         int rc;
1614
1615         if (def_reserved_size >= 0)
1616                 sg_big_buff = def_reserved_size;
1617
1618         rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1619                                     SG_MAX_DEVS, "sg");
1620         if (rc)
1621                 return rc;
1622         sg_sysfs_class = class_simple_create(THIS_MODULE, "scsi_generic");
1623         if ( IS_ERR(sg_sysfs_class) ) {
1624                 rc = PTR_ERR(sg_sysfs_class);
1625                 goto err_out;
1626         }
1627         sg_sysfs_valid = 1;
1628         rc = scsi_register_interface(&sg_interface);
1629         if (0 == rc) {
1630 #ifdef CONFIG_SCSI_PROC_FS
1631                 sg_proc_init();
1632 #endif                          /* CONFIG_SCSI_PROC_FS */
1633                 return 0;
1634         }
1635         class_simple_destroy(sg_sysfs_class);
1636 err_out:
1637         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1638         return rc;
1639 }
1640
1641 static void __exit
1642 exit_sg(void)
1643 {
1644 #ifdef CONFIG_SCSI_PROC_FS
1645         sg_proc_cleanup();
1646 #endif                          /* CONFIG_SCSI_PROC_FS */
1647         scsi_unregister_interface(&sg_interface);
1648         class_simple_destroy(sg_sysfs_class);
1649         sg_sysfs_valid = 0;
1650         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1651                                  SG_MAX_DEVS);
1652         if (sg_dev_arr != NULL) {
1653                 kfree((char *) sg_dev_arr);
1654                 sg_dev_arr = NULL;
1655         }
1656         sg_dev_max = 0;
1657 }
1658
1659 static int
1660 sg_start_req(Sg_request * srp)
1661 {
1662         int res;
1663         Sg_fd *sfp = srp->parentfp;
1664         sg_io_hdr_t *hp = &srp->header;
1665         int dxfer_len = (int) hp->dxfer_len;
1666         int dxfer_dir = hp->dxfer_direction;
1667         Sg_scatter_hold *req_schp = &srp->data;
1668         Sg_scatter_hold *rsv_schp = &sfp->reserve;
1669
1670         SCSI_LOG_TIMEOUT(4, printk("sg_start_req: dxfer_len=%d\n", dxfer_len));
1671         if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1672                 return 0;
1673         if (sg_allow_dio && (hp->flags & SG_FLAG_DIRECT_IO) &&
1674             (dxfer_dir != SG_DXFER_UNKNOWN) && (0 == hp->iovec_count) &&
1675             (!sfp->parentdp->device->host->unchecked_isa_dma)) {
1676                 res = sg_build_direct(srp, sfp, dxfer_len);
1677                 if (res <= 0)   /* -ve -> error, 0 -> done, 1 -> try indirect */
1678                         return res;
1679         }
1680         if ((!sg_res_in_use(sfp)) && (dxfer_len <= rsv_schp->bufflen))
1681                 sg_link_reserve(sfp, srp, dxfer_len);
1682         else {
1683                 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1684                 if (res) {
1685                         sg_remove_scat(req_schp);
1686                         return res;
1687                 }
1688         }
1689         return 0;
1690 }
1691
1692 static void
1693 sg_finish_rem_req(Sg_request * srp)
1694 {
1695         Sg_fd *sfp = srp->parentfp;
1696         Sg_scatter_hold *req_schp = &srp->data;
1697
1698         SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n", (int) srp->res_used));
1699         if (srp->res_used)
1700                 sg_unlink_reserve(sfp, srp);
1701         else
1702                 sg_remove_scat(req_schp);
1703         sg_remove_request(sfp, srp);
1704 }
1705
1706 static int
1707 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1708 {
1709         int ret_sz;
1710         int elem_sz = sizeof (struct scatterlist);
1711         int sg_bufflen = tablesize * elem_sz;
1712         int mx_sc_elems = tablesize;
1713
1714         schp->buffer = sg_page_malloc(sg_bufflen, sfp->low_dma, &ret_sz);
1715         if (!schp->buffer)
1716                 return -ENOMEM;
1717         else if (ret_sz != sg_bufflen) {
1718                 sg_bufflen = ret_sz;
1719                 mx_sc_elems = sg_bufflen / elem_sz;
1720         }
1721         schp->sglist_len = sg_bufflen;
1722         memset(schp->buffer, 0, sg_bufflen);
1723         return mx_sc_elems;     /* number of scat_gath elements allocated */
1724 }
1725
1726 #ifdef SG_ALLOW_DIO_CODE
1727 /* vvvvvvvv  following code borrowed from st driver's direct IO vvvvvvvvv */
1728         /* hopefully this generic code will moved to a library */
1729
1730 /* Pin down user pages and put them into a scatter gather list. Returns <= 0 if
1731    - mapping of all pages not successful
1732    - any page is above max_pfn
1733    (i.e., either completely successful or fails)
1734 */
1735 static int
1736 st_map_user_pages(struct scatterlist *sgl, const unsigned int max_pages,
1737                   unsigned long uaddr, size_t count, int rw,
1738                   unsigned long max_pfn)
1739 {
1740         int res, i, j;
1741         unsigned int nr_pages;
1742         struct page **pages;
1743
1744         nr_pages = ((uaddr & ~PAGE_MASK) + count + ~PAGE_MASK) >> PAGE_SHIFT;
1745
1746         /* User attempted Overflow! */
1747         if ((uaddr + count) < uaddr)
1748                 return -EINVAL;
1749
1750         /* Too big */
1751         if (nr_pages > max_pages)
1752                 return -ENOMEM;
1753
1754         /* Hmm? */
1755         if (count == 0)
1756                 return 0;
1757
1758         if ((pages = kmalloc(max_pages * sizeof(*pages), GFP_ATOMIC)) == NULL)
1759                 return -ENOMEM;
1760
1761         /* Try to fault in all of the necessary pages */
1762         down_read(&current->mm->mmap_sem);
1763         /* rw==READ means read from drive, write into memory area */
1764         res = get_user_pages(
1765                 current,
1766                 current->mm,
1767                 uaddr,
1768                 nr_pages,
1769                 rw == READ,
1770                 0, /* don't force */
1771                 pages,
1772                 NULL);
1773         up_read(&current->mm->mmap_sem);
1774
1775         /* Errors and no page mapped should return here */
1776         if (res < nr_pages)
1777                 goto out_unmap;
1778
1779         for (i=0; i < nr_pages; i++) {
1780                 /* FIXME: flush superflous for rw==READ,
1781                  * probably wrong function for rw==WRITE
1782                  */
1783                 flush_dcache_page(pages[i]);
1784                 if (page_to_pfn(pages[i]) > max_pfn)
1785                         goto out_unlock;
1786                 /* ?? Is locking needed? I don't think so */
1787                 /* if (TestSetPageLocked(pages[i]))
1788                    goto out_unlock; */
1789         }
1790
1791         /* Populate the scatter/gather list */
1792         sgl[0].page = pages[0];
1793         sgl[0].offset = uaddr & ~PAGE_MASK;
1794         if (nr_pages > 1) {
1795                 sgl[0].length = PAGE_SIZE - sgl[0].offset;
1796                 count -= sgl[0].length;
1797                 for (i=1; i < nr_pages ; i++) {
1798                         sgl[i].offset = 0;
1799                         sgl[i].page = pages[i];
1800                         sgl[i].length = count < PAGE_SIZE ? count : PAGE_SIZE;
1801                         count -= PAGE_SIZE;
1802                 }
1803         }
1804         else {
1805                 sgl[0].length = count;
1806         }
1807
1808         kfree(pages);
1809         return nr_pages;
1810
1811  out_unlock:
1812         /* for (j=0; j < i; j++)
1813            unlock_page(pages[j]); */
1814         res = 0;
1815  out_unmap:
1816         if (res > 0)
1817                 for (j=0; j < res; j++)
1818                         page_cache_release(pages[j]);
1819         kfree(pages);
1820         return res;
1821 }
1822
1823
1824 /* And unmap them... */
1825 static int
1826 st_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_pages,
1827                     int dirtied)
1828 {
1829         int i;
1830
1831         for (i=0; i < nr_pages; i++) {
1832                 if (dirtied && !PageReserved(sgl[i].page))
1833                         SetPageDirty(sgl[i].page);
1834                 /* unlock_page(sgl[i].page); */
1835                 /* FIXME: cache flush missing for rw==READ
1836                  * FIXME: call the correct reference counting function
1837                  */
1838                 page_cache_release(sgl[i].page);
1839         }
1840
1841         return 0;
1842 }
1843
1844 /* ^^^^^^^^  above code borrowed from st driver's direct IO ^^^^^^^^^ */
1845 #endif
1846
1847
1848 /* Returns: -ve -> error, 0 -> done, 1 -> try indirect */
1849 static int
1850 sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len)
1851 {
1852 #ifdef SG_ALLOW_DIO_CODE
1853         sg_io_hdr_t *hp = &srp->header;
1854         Sg_scatter_hold *schp = &srp->data;
1855         int sg_tablesize = sfp->parentdp->sg_tablesize;
1856         struct scatterlist *sgl;
1857         int mx_sc_elems, res;
1858         struct scsi_device *sdev = sfp->parentdp->device;
1859
1860         if (((unsigned long)hp->dxferp &
1861                         queue_dma_alignment(sdev->request_queue)) != 0)
1862                 return 1;
1863         mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1864         if (mx_sc_elems <= 0) {
1865                 return 1;
1866         }
1867         sgl = (struct scatterlist *)schp->buffer;
1868         res = st_map_user_pages(sgl, mx_sc_elems, (unsigned long)hp->dxferp, dxfer_len,
1869                                 (SG_DXFER_TO_DEV == hp->dxfer_direction) ? 1 : 0, ULONG_MAX);
1870         if (res <= 0)
1871                 return 1;
1872         schp->k_use_sg = res;
1873         schp->dio_in_use = 1;
1874         hp->info |= SG_INFO_DIRECT_IO;
1875         return 0;
1876 #else
1877         return 1;
1878 #endif
1879 }
1880
1881 static int
1882 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1883 {
1884         int ret_sz;
1885         int blk_size = buff_size;
1886         unsigned char *p = NULL;
1887
1888         if ((blk_size < 0) || (!sfp))
1889                 return -EFAULT;
1890         if (0 == blk_size)
1891                 ++blk_size;     /* don't know why */
1892 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1893         blk_size = (blk_size + SG_SECTOR_MSK) & (~SG_SECTOR_MSK);
1894         SCSI_LOG_TIMEOUT(4, printk("sg_build_indirect: buff_size=%d, blk_size=%d\n",
1895                                    buff_size, blk_size));
1896         if (blk_size <= SG_SCATTER_SZ) {
1897                 p = sg_page_malloc(blk_size, sfp->low_dma, &ret_sz);
1898                 if (!p)
1899                         return -ENOMEM;
1900                 if (blk_size == ret_sz) {       /* got it on the first attempt */
1901                         schp->k_use_sg = 0;
1902                         schp->buffer = p;
1903                         schp->bufflen = blk_size;
1904                         schp->b_malloc_len = blk_size;
1905                         return 0;
1906                 }
1907         } else {
1908                 p = sg_page_malloc(SG_SCATTER_SZ, sfp->low_dma, &ret_sz);
1909                 if (!p)
1910                         return -ENOMEM;
1911         }
1912 /* Want some local declarations, so start new block ... */
1913         {                       /* lets try and build a scatter gather list */
1914                 struct scatterlist *sclp;
1915                 int k, rem_sz, num;
1916                 int mx_sc_elems;
1917                 int sg_tablesize = sfp->parentdp->sg_tablesize;
1918                 int first = 1;
1919
1920                 /* N.B. ret_sz carried into this block ... */
1921                 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1922                 if (mx_sc_elems < 0)
1923                         return mx_sc_elems;     /* most likely -ENOMEM */
1924
1925                 for (k = 0, sclp = schp->buffer, rem_sz = blk_size;
1926                      (rem_sz > 0) && (k < mx_sc_elems);
1927                      ++k, rem_sz -= ret_sz, ++sclp) {
1928                         if (first)
1929                                 first = 0;
1930                         else {
1931                                 num =
1932                                     (rem_sz >
1933                                      SG_SCATTER_SZ) ? SG_SCATTER_SZ : rem_sz;
1934                                 p = sg_page_malloc(num, sfp->low_dma, &ret_sz);
1935                                 if (!p)
1936                                         break;
1937                         }
1938                         sclp->page = virt_to_page(p);
1939                         sclp->offset = offset_in_page(p);
1940                         sclp->length = ret_sz;
1941
1942                         SCSI_LOG_TIMEOUT(5, printk("sg_build_build: k=%d, a=0x%p, len=%d\n",
1943                                           k, sg_scatg2virt(sclp), ret_sz));
1944                 }               /* end of for loop */
1945                 schp->k_use_sg = k;
1946                 SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, rem_sz=%d\n", k, rem_sz));
1947                 schp->bufflen = blk_size;
1948                 if (rem_sz > 0) /* must have failed */
1949                         return -ENOMEM;
1950         }
1951         return 0;
1952 }
1953
1954 static int
1955 sg_write_xfer(Sg_request * srp)
1956 {
1957         sg_io_hdr_t *hp = &srp->header;
1958         Sg_scatter_hold *schp = &srp->data;
1959         int num_xfer = 0;
1960         int j, k, onum, usglen, ksglen, res;
1961         int iovec_count = (int) hp->iovec_count;
1962         int dxfer_dir = hp->dxfer_direction;
1963         unsigned char *p;
1964         unsigned char __user *up;
1965         int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
1966
1967         if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_TO_DEV == dxfer_dir) ||
1968             (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
1969                 num_xfer = (int) (new_interface ? hp->dxfer_len : hp->flags);
1970                 if (schp->bufflen < num_xfer)
1971                         num_xfer = schp->bufflen;
1972         }
1973         if ((num_xfer <= 0) || (schp->dio_in_use) ||
1974             (new_interface
1975              && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
1976                 return 0;
1977
1978         SCSI_LOG_TIMEOUT(4, printk("sg_write_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
1979                           num_xfer, iovec_count, schp->k_use_sg));
1980         if (iovec_count) {
1981                 onum = iovec_count;
1982                 if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum))
1983                         return -EFAULT;
1984         } else
1985                 onum = 1;
1986
1987         if (0 == schp->k_use_sg) {      /* kernel has single buffer */
1988                 for (j = 0, p = schp->buffer; j < onum; ++j) {
1989                         res = sg_u_iovec(hp, iovec_count, j, 1, &usglen, &up);
1990                         if (res)
1991                                 return res;
1992                         usglen = (num_xfer > usglen) ? usglen : num_xfer;
1993                         if (__copy_from_user(p, up, usglen))
1994                                 return -EFAULT;
1995                         p += usglen;
1996                         num_xfer -= usglen;
1997                         if (num_xfer <= 0)
1998                                 return 0;
1999                 }
2000         } else {                /* kernel using scatter gather list */
2001                 struct scatterlist *sclp = (struct scatterlist *) schp->buffer;
2002
2003                 ksglen = (int) sclp->length;
2004                 p = sg_scatg2virt(sclp);
2005                 for (j = 0, k = 0; j < onum; ++j) {
2006                         res = sg_u_iovec(hp, iovec_count, j, 1, &usglen, &up);
2007                         if (res)
2008                                 return res;
2009
2010                         for (; p; ++sclp, ksglen = (int) sclp->length,
2011                                   p = sg_scatg2virt(sclp)) {
2012                                 if (usglen <= 0)
2013                                         break;
2014                                 if (ksglen > usglen) {
2015                                         if (usglen >= num_xfer) {
2016                                                 if (__copy_from_user
2017                                                     (p, up, num_xfer))
2018                                                         return -EFAULT;
2019                                                 return 0;
2020                                         }
2021                                         if (__copy_from_user(p, up, usglen))
2022                                                 return -EFAULT;
2023                                         p += usglen;
2024                                         ksglen -= usglen;
2025                                         break;
2026                                 } else {
2027                                         if (ksglen >= num_xfer) {
2028                                                 if (__copy_from_user
2029                                                     (p, up, num_xfer))
2030                                                         return -EFAULT;
2031                                                 return 0;
2032                                         }
2033                                         if (__copy_from_user(p, up, ksglen))
2034                                                 return -EFAULT;
2035                                         up += ksglen;
2036                                         usglen -= ksglen;
2037                                 }
2038                                 ++k;
2039                                 if (k >= schp->k_use_sg)
2040                                         return 0;
2041                         }
2042                 }
2043         }
2044         return 0;
2045 }
2046
2047 static int
2048 sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
2049            int wr_xf, int *countp, unsigned char __user **up)
2050 {
2051         int num_xfer = (int) hp->dxfer_len;
2052         unsigned char __user *p = hp->dxferp;
2053         int count;
2054
2055         if (0 == sg_num) {
2056                 if (wr_xf && ('\0' == hp->interface_id))
2057                         count = (int) hp->flags;        /* holds "old" input_size */
2058                 else
2059                         count = num_xfer;
2060         } else {
2061                 sg_iovec_t iovec;
2062                 if (__copy_from_user(&iovec, p + ind*SZ_SG_IOVEC, SZ_SG_IOVEC))
2063                         return -EFAULT;
2064                 p = iovec.iov_base;
2065                 count = (int) iovec.iov_len;
2066         }
2067         if (!access_ok(wr_xf ? VERIFY_READ : VERIFY_WRITE, p, count))
2068                 return -EFAULT;
2069         if (up)
2070                 *up = p;
2071         if (countp)
2072                 *countp = count;
2073         return 0;
2074 }
2075
2076 static void
2077 sg_remove_scat(Sg_scatter_hold * schp)
2078 {
2079         SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
2080         if (schp->buffer && (schp->sglist_len > 0)) {
2081                 struct scatterlist *sclp = (struct scatterlist *) schp->buffer;
2082
2083                 if (schp->dio_in_use) {
2084 #ifdef SG_ALLOW_DIO_CODE
2085                         st_unmap_user_pages(sclp, schp->k_use_sg, TRUE);
2086 #endif
2087                 } else {
2088                         int k;
2089
2090                         for (k = 0; (k < schp->k_use_sg) && sg_scatg2virt(sclp);
2091                              ++k, ++sclp) {
2092                                 SCSI_LOG_TIMEOUT(5, printk(
2093                                     "sg_remove_scat: k=%d, a=0x%p, len=%d\n",
2094                                     k, sg_scatg2virt(sclp), sclp->length));
2095                                 sg_page_free(sg_scatg2virt(sclp), sclp->length);
2096                                 sclp->page = NULL;
2097                                 sclp->offset = 0;
2098                                 sclp->length = 0;
2099                         }
2100                 }
2101                 sg_page_free(schp->buffer, schp->sglist_len);
2102         } else if (schp->buffer)
2103                 sg_page_free(schp->buffer, schp->b_malloc_len);
2104         memset(schp, 0, sizeof (*schp));
2105 }
2106
2107 static int
2108 sg_read_xfer(Sg_request * srp)
2109 {
2110         sg_io_hdr_t *hp = &srp->header;
2111         Sg_scatter_hold *schp = &srp->data;
2112         int num_xfer = 0;
2113         int j, k, onum, usglen, ksglen, res;
2114         int iovec_count = (int) hp->iovec_count;
2115         int dxfer_dir = hp->dxfer_direction;
2116         unsigned char *p;
2117         unsigned char __user *up;
2118         int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
2119
2120         if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_FROM_DEV == dxfer_dir)
2121             || (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
2122                 num_xfer = hp->dxfer_len;
2123                 if (schp->bufflen < num_xfer)
2124                         num_xfer = schp->bufflen;
2125         }
2126         if ((num_xfer <= 0) || (schp->dio_in_use) ||
2127             (new_interface
2128              && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
2129                 return 0;
2130
2131         SCSI_LOG_TIMEOUT(4, printk("sg_read_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
2132                           num_xfer, iovec_count, schp->k_use_sg));
2133         if (iovec_count) {
2134                 onum = iovec_count;
2135                 if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum))
2136                         return -EFAULT;
2137         } else
2138                 onum = 1;
2139
2140         if (0 == schp->k_use_sg) {      /* kernel has single buffer */
2141                 for (j = 0, p = schp->buffer; j < onum; ++j) {
2142                         res = sg_u_iovec(hp, iovec_count, j, 0, &usglen, &up);
2143                         if (res)
2144                                 return res;
2145                         usglen = (num_xfer > usglen) ? usglen : num_xfer;
2146                         if (__copy_to_user(up, p, usglen))
2147                                 return -EFAULT;
2148                         p += usglen;
2149                         num_xfer -= usglen;
2150                         if (num_xfer <= 0)
2151                                 return 0;
2152                 }
2153         } else {                /* kernel using scatter gather list */
2154                 struct scatterlist *sclp = (struct scatterlist *) schp->buffer;
2155
2156                 ksglen = (int) sclp->length;
2157                 p = sg_scatg2virt(sclp);
2158                 for (j = 0, k = 0; j < onum; ++j) {
2159                         res = sg_u_iovec(hp, iovec_count, j, 0, &usglen, &up);
2160                         if (res)
2161                                 return res;
2162
2163                         for (; p; ++sclp, ksglen = (int) sclp->length,
2164                                   p = sg_scatg2virt(sclp)) {
2165                                 if (usglen <= 0)
2166                                         break;
2167                                 if (ksglen > usglen) {
2168                                         if (usglen >= num_xfer) {
2169                                                 if (__copy_to_user
2170                                                     (up, p, num_xfer))
2171                                                         return -EFAULT;
2172                                                 return 0;
2173                                         }
2174                                         if (__copy_to_user(up, p, usglen))
2175                                                 return -EFAULT;
2176                                         p += usglen;
2177                                         ksglen -= usglen;
2178                                         break;
2179                                 } else {
2180                                         if (ksglen >= num_xfer) {
2181                                                 if (__copy_to_user
2182                                                     (up, p, num_xfer))
2183                                                         return -EFAULT;
2184                                                 return 0;
2185                                         }
2186                                         if (__copy_to_user(up, p, ksglen))
2187                                                 return -EFAULT;
2188                                         up += ksglen;
2189                                         usglen -= ksglen;
2190                                 }
2191                                 ++k;
2192                                 if (k >= schp->k_use_sg)
2193                                         return 0;
2194                         }
2195                 }
2196         }
2197         return 0;
2198 }
2199
2200 static int
2201 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
2202 {
2203         Sg_scatter_hold *schp = &srp->data;
2204
2205         SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n",
2206                                    num_read_xfer));
2207         if ((!outp) || (num_read_xfer <= 0))
2208                 return 0;
2209         if (schp->k_use_sg > 0) {
2210                 int k, num;
2211                 struct scatterlist *sclp = (struct scatterlist *) schp->buffer;
2212
2213                 for (k = 0; (k < schp->k_use_sg) && sg_scatg2virt(sclp);
2214                      ++k, ++sclp) {
2215                         num = (int) sclp->length;
2216                         if (num > num_read_xfer) {
2217                                 if (__copy_to_user
2218                                     (outp, sg_scatg2virt(sclp), num_read_xfer))
2219                                         return -EFAULT;
2220                                 break;
2221                         } else {
2222                                 if (__copy_to_user
2223                                     (outp, sg_scatg2virt(sclp), num))
2224                                         return -EFAULT;
2225                                 num_read_xfer -= num;
2226                                 if (num_read_xfer <= 0)
2227                                         break;
2228                                 outp += num;
2229                         }
2230                 }
2231         } else {
2232                 if (__copy_to_user(outp, schp->buffer, num_read_xfer))
2233                         return -EFAULT;
2234         }
2235         return 0;
2236 }
2237
2238 static void
2239 sg_build_reserve(Sg_fd * sfp, int req_size)
2240 {
2241         Sg_scatter_hold *schp = &sfp->reserve;
2242
2243         SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
2244         do {
2245                 if (req_size < PAGE_SIZE)
2246                         req_size = PAGE_SIZE;
2247                 if (0 == sg_build_indirect(schp, sfp, req_size))
2248                         return;
2249                 else
2250                         sg_remove_scat(schp);
2251                 req_size >>= 1; /* divide by 2 */
2252         } while (req_size > (PAGE_SIZE / 2));
2253 }
2254
2255 static void
2256 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2257 {
2258         Sg_scatter_hold *req_schp = &srp->data;
2259         Sg_scatter_hold *rsv_schp = &sfp->reserve;
2260
2261         srp->res_used = 1;
2262         SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
2263         size = (size + 1) & (~1);       /* round to even for aha1542 */
2264         if (rsv_schp->k_use_sg > 0) {
2265                 int k, num;
2266                 int rem = size;
2267                 struct scatterlist *sclp =
2268                     (struct scatterlist *) rsv_schp->buffer;
2269
2270                 for (k = 0; k < rsv_schp->k_use_sg; ++k, ++sclp) {
2271                         num = (int) sclp->length;
2272                         if (rem <= num) {
2273                                 if (0 == k) {
2274                                         req_schp->k_use_sg = 0;
2275                                         req_schp->buffer = sg_scatg2virt(sclp);
2276                                 } else {
2277                                         sfp->save_scat_len = num;
2278                                         sclp->length = (unsigned) rem;
2279                                         req_schp->k_use_sg = k + 1;
2280                                         req_schp->sglist_len =
2281                                             rsv_schp->sglist_len;
2282                                         req_schp->buffer = rsv_schp->buffer;
2283                                 }
2284                                 req_schp->bufflen = size;
2285                                 req_schp->b_malloc_len = rsv_schp->b_malloc_len;
2286                                 break;
2287                         } else
2288                                 rem -= num;
2289                 }
2290                 if (k >= rsv_schp->k_use_sg)
2291                         SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
2292         } else {
2293                 req_schp->k_use_sg = 0;
2294                 req_schp->bufflen = size;
2295                 req_schp->buffer = rsv_schp->buffer;
2296                 req_schp->b_malloc_len = rsv_schp->b_malloc_len;
2297         }
2298 }
2299
2300 static void
2301 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2302 {
2303         Sg_scatter_hold *req_schp = &srp->data;
2304         Sg_scatter_hold *rsv_schp = &sfp->reserve;
2305
2306         SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->k_use_sg=%d\n",
2307                                    (int) req_schp->k_use_sg));
2308         if ((rsv_schp->k_use_sg > 0) && (req_schp->k_use_sg > 0)) {
2309                 struct scatterlist *sclp =
2310                     (struct scatterlist *) rsv_schp->buffer;
2311
2312                 if (sfp->save_scat_len > 0)
2313                         (sclp + (req_schp->k_use_sg - 1))->length =
2314                             (unsigned) sfp->save_scat_len;
2315                 else
2316                         SCSI_LOG_TIMEOUT(1, printk ("sg_unlink_reserve: BAD save_scat_len\n"));
2317         }
2318         req_schp->k_use_sg = 0;
2319         req_schp->bufflen = 0;
2320         req_schp->buffer = NULL;
2321         req_schp->sglist_len = 0;
2322         sfp->save_scat_len = 0;
2323         srp->res_used = 0;
2324 }
2325
2326 static Sg_request *
2327 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2328 {
2329         Sg_request *resp;
2330         unsigned long iflags;
2331
2332         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2333         for (resp = sfp->headrp; resp; resp = resp->nextrp) {
2334                 /* look for requests that are ready + not SG_IO owned */
2335                 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2336                     ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2337                         resp->done = 2; /* guard against other readers */
2338                         break;
2339                 }
2340         }
2341         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2342         return resp;
2343 }
2344
2345 #ifdef CONFIG_SCSI_PROC_FS
2346 static Sg_request *
2347 sg_get_nth_request(Sg_fd * sfp, int nth)
2348 {
2349         Sg_request *resp;
2350         unsigned long iflags;
2351         int k;
2352
2353         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2354         for (k = 0, resp = sfp->headrp; resp && (k < nth);
2355              ++k, resp = resp->nextrp) ;
2356         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2357         return resp;
2358 }
2359 #endif
2360
2361 /* always adds to end of list */
2362 static Sg_request *
2363 sg_add_request(Sg_fd * sfp)
2364 {
2365         int k;
2366         unsigned long iflags;
2367         Sg_request *resp;
2368         Sg_request *rp = sfp->req_arr;
2369
2370         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2371         resp = sfp->headrp;
2372         if (!resp) {
2373                 memset(rp, 0, sizeof (Sg_request));
2374                 rp->parentfp = sfp;
2375                 resp = rp;
2376                 sfp->headrp = resp;
2377         } else {
2378                 if (0 == sfp->cmd_q)
2379                         resp = NULL;    /* command queuing disallowed */
2380                 else {
2381                         for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2382                                 if (!rp->parentfp)
2383                                         break;
2384                         }
2385                         if (k < SG_MAX_QUEUE) {
2386                                 memset(rp, 0, sizeof (Sg_request));
2387                                 rp->parentfp = sfp;
2388                                 while (resp->nextrp)
2389                                         resp = resp->nextrp;
2390                                 resp->nextrp = rp;
2391                                 resp = rp;
2392                         } else
2393                                 resp = NULL;
2394                 }
2395         }
2396         if (resp) {
2397                 resp->nextrp = NULL;
2398                 resp->header.duration = jiffies;
2399                 resp->my_cmdp = NULL;
2400         }
2401         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2402         return resp;
2403 }
2404
2405 /* Return of 1 for found; 0 for not found */
2406 static int
2407 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2408 {
2409         Sg_request *prev_rp;
2410         Sg_request *rp;
2411         unsigned long iflags;
2412         int res = 0;
2413
2414         if ((!sfp) || (!srp) || (!sfp->headrp))
2415                 return res;
2416         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2417         prev_rp = sfp->headrp;
2418         if (srp == prev_rp) {
2419                 sfp->headrp = prev_rp->nextrp;
2420                 prev_rp->parentfp = NULL;
2421                 res = 1;
2422         } else {
2423                 while ((rp = prev_rp->nextrp)) {
2424                         if (srp == rp) {
2425                                 prev_rp->nextrp = rp->nextrp;
2426                                 rp->parentfp = NULL;
2427                                 res = 1;
2428                                 break;
2429                         }
2430                         prev_rp = rp;
2431                 }
2432         }
2433         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2434         return res;
2435 }
2436
2437 #ifdef CONFIG_SCSI_PROC_FS
2438 static Sg_fd *
2439 sg_get_nth_sfp(Sg_device * sdp, int nth)
2440 {
2441         Sg_fd *resp;
2442         unsigned long iflags;
2443         int k;
2444
2445         read_lock_irqsave(&sg_dev_arr_lock, iflags);
2446         for (k = 0, resp = sdp->headfp; resp && (k < nth);
2447              ++k, resp = resp->nextfp) ;
2448         read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2449         return resp;
2450 }
2451 #endif
2452
2453 static Sg_fd *
2454 sg_add_sfp(Sg_device * sdp, int dev)
2455 {
2456         Sg_fd *sfp;
2457         unsigned long iflags;
2458
2459         sfp = (Sg_fd *) sg_page_malloc(sizeof (Sg_fd), 0, NULL);
2460         if (!sfp)
2461                 return NULL;
2462         memset(sfp, 0, sizeof (Sg_fd));
2463         init_waitqueue_head(&sfp->read_wait);
2464         rwlock_init(&sfp->rq_list_lock);
2465
2466         sfp->timeout = SG_DEFAULT_TIMEOUT;
2467         sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2468         sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2469         sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
2470             sdp->device->host->unchecked_isa_dma : 1;
2471         sfp->cmd_q = SG_DEF_COMMAND_Q;
2472         sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2473         sfp->parentdp = sdp;
2474         write_lock_irqsave(&sg_dev_arr_lock, iflags);
2475         if (!sdp->headfp)
2476                 sdp->headfp = sfp;
2477         else {                  /* add to tail of existing list */
2478                 Sg_fd *pfp = sdp->headfp;
2479                 while (pfp->nextfp)
2480                         pfp = pfp->nextfp;
2481                 pfp->nextfp = sfp;
2482         }
2483         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2484         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));
2485         sg_build_reserve(sfp, sg_big_buff);
2486         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp:   bufflen=%d, k_use_sg=%d\n",
2487                            sfp->reserve.bufflen, sfp->reserve.k_use_sg));
2488         return sfp;
2489 }
2490
2491 static void
2492 __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2493 {
2494         Sg_fd *fp;
2495         Sg_fd *prev_fp;
2496
2497         prev_fp = sdp->headfp;
2498         if (sfp == prev_fp)
2499                 sdp->headfp = prev_fp->nextfp;
2500         else {
2501                 while ((fp = prev_fp->nextfp)) {
2502                         if (sfp == fp) {
2503                                 prev_fp->nextfp = fp->nextfp;
2504                                 break;
2505                         }
2506                         prev_fp = fp;
2507                 }
2508         }
2509         if (sfp->reserve.bufflen > 0) {
2510                 SCSI_LOG_TIMEOUT(6,
2511                         printk("__sg_remove_sfp:    bufflen=%d, k_use_sg=%d\n",
2512                         (int) sfp->reserve.bufflen, (int) sfp->reserve.k_use_sg));
2513                 if (sfp->mmap_called)
2514                         sg_rb_correct4mmap(&sfp->reserve, 0);   /* undo correction */
2515                 sg_remove_scat(&sfp->reserve);
2516         }
2517         sfp->parentdp = NULL;
2518         SCSI_LOG_TIMEOUT(6, printk("__sg_remove_sfp:    sfp=0x%p\n", sfp));
2519         sg_page_free((char *) sfp, sizeof (Sg_fd));
2520 }
2521
2522 /* Returns 0 in normal case, 1 when detached and sdp object removed */
2523 static int
2524 sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2525 {
2526         Sg_request *srp;
2527         Sg_request *tsrp;
2528         int dirty = 0;
2529         int res = 0;
2530
2531         for (srp = sfp->headrp; srp; srp = tsrp) {
2532                 tsrp = srp->nextrp;
2533                 if (sg_srp_done(srp, sfp))
2534                         sg_finish_rem_req(srp);
2535                 else
2536                         ++dirty;
2537         }
2538         if (0 == dirty) {
2539                 unsigned long iflags;
2540
2541                 write_lock_irqsave(&sg_dev_arr_lock, iflags);
2542                 __sg_remove_sfp(sdp, sfp);
2543                 if (sdp->detached && (NULL == sdp->headfp)) {
2544                         int k, maxd;
2545
2546                         maxd = sg_dev_max;
2547                         for (k = 0; k < maxd; ++k) {
2548                                 if (sdp == sg_dev_arr[k])
2549                                         break;
2550                         }
2551                         if (k < maxd)
2552                                 sg_dev_arr[k] = NULL;
2553                         kfree((char *) sdp);
2554                         res = 1;
2555                 }
2556                 write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2557         } else {
2558                 /* MOD_INC's to inhibit unloading sg and associated adapter driver */
2559                 /* only bump the access_count if we actually succeeded in
2560                  * throwing another counter on the host module */
2561                 scsi_device_get(sdp->device);   /* XXX: retval ignored? */
2562                 sfp->closed = 1;        /* flag dirty state on this fd */
2563                 SCSI_LOG_TIMEOUT(1, printk("sg_remove_sfp: worrisome, %d writes pending\n",
2564                                   dirty));
2565         }
2566         return res;
2567 }
2568
2569 static int
2570 sg_res_in_use(Sg_fd * sfp)
2571 {
2572         const Sg_request *srp;
2573         unsigned long iflags;
2574
2575         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2576         for (srp = sfp->headrp; srp; srp = srp->nextrp)
2577                 if (srp->res_used)
2578                         break;
2579         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2580         return srp ? 1 : 0;
2581 }
2582
2583 /* If retSzp==NULL want exact size or fail */
2584 static char *
2585 sg_page_malloc(int rqSz, int lowDma, int *retSzp)
2586 {
2587         char *resp = NULL;
2588         int page_mask;
2589         int order, a_size;
2590         int resSz = rqSz;
2591
2592         if (rqSz <= 0)
2593                 return resp;
2594
2595         if (lowDma)
2596                 page_mask = GFP_ATOMIC | GFP_DMA | __GFP_NOWARN;
2597         else
2598                 page_mask = GFP_ATOMIC | __GFP_NOWARN;
2599
2600         for (order = 0, a_size = PAGE_SIZE; a_size < rqSz;
2601              order++, a_size <<= 1) ;
2602         resp = (char *) __get_free_pages(page_mask, order);
2603         while ((!resp) && order && retSzp) {
2604                 --order;
2605                 a_size >>= 1;   /* divide by 2, until PAGE_SIZE */
2606                 resp = (char *) __get_free_pages(page_mask, order);     /* try half */
2607                 resSz = a_size;
2608         }
2609         if (resp) {
2610                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2611                         memset(resp, 0, resSz);
2612                 if (retSzp)
2613                         *retSzp = resSz;
2614         }
2615         return resp;
2616 }
2617
2618 static void
2619 sg_page_free(char *buff, int size)
2620 {
2621         int order, a_size;
2622
2623         if (!buff)
2624                 return;
2625         for (order = 0, a_size = PAGE_SIZE; a_size < size;
2626              order++, a_size <<= 1) ;
2627         free_pages((unsigned long) buff, order);
2628 }
2629
2630 #ifndef MAINTENANCE_IN_CMD
2631 #define MAINTENANCE_IN_CMD 0xa3
2632 #endif
2633
2634 static unsigned char allow_ops[] = { TEST_UNIT_READY, REQUEST_SENSE,
2635         INQUIRY, READ_CAPACITY, READ_BUFFER, READ_6, READ_10, READ_12,
2636         READ_16, MODE_SENSE, MODE_SENSE_10, LOG_SENSE, REPORT_LUNS,
2637         SERVICE_ACTION_IN, RECEIVE_DIAGNOSTIC, READ_LONG, MAINTENANCE_IN_CMD
2638 };
2639
2640 static int
2641 sg_allow_access(unsigned char opcode, char dev_type)
2642 {
2643         int k;
2644
2645         if (TYPE_SCANNER == dev_type)   /* TYPE_ROM maybe burner */
2646                 return 1;
2647         for (k = 0; k < sizeof (allow_ops); ++k) {
2648                 if (opcode == allow_ops[k])
2649                         return 1;
2650         }
2651         return 0;
2652 }
2653
2654 #ifdef CONFIG_SCSI_PROC_FS
2655 static int
2656 sg_last_dev(void)
2657 {
2658         int k;
2659         unsigned long iflags;
2660
2661         read_lock_irqsave(&sg_dev_arr_lock, iflags);
2662         for (k = sg_dev_max - 1; k >= 0; --k)
2663                 if (sg_dev_arr[k] && sg_dev_arr[k]->device)
2664                         break;
2665         read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2666         return k + 1;           /* origin 1 */
2667 }
2668 #endif
2669
2670 static Sg_device *
2671 sg_get_dev(int dev)
2672 {
2673         Sg_device *sdp = NULL;
2674         unsigned long iflags;
2675
2676         if (sg_dev_arr && (dev >= 0)) {
2677                 read_lock_irqsave(&sg_dev_arr_lock, iflags);
2678                 if (dev < sg_dev_max)
2679                         sdp = sg_dev_arr[dev];
2680                 read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2681         }
2682         return sdp;
2683 }
2684
2685 #ifdef CONFIG_SCSI_PROC_FS
2686
2687 static struct proc_dir_entry *sg_proc_sgp = NULL;
2688
2689 static char sg_proc_sg_dirname[] = "scsi/sg";
2690
2691 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2692
2693 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2694 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2695                                   size_t count, loff_t *off);
2696 static struct file_operations adio_fops = {
2697         /* .owner, .read and .llseek added in sg_proc_init() */
2698         .open = sg_proc_single_open_adio,
2699         .write = sg_proc_write_adio,
2700         .release = single_release,
2701 };
2702
2703 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2704 static ssize_t sg_proc_write_dressz(struct file *filp,
2705                 const char __user *buffer, size_t count, loff_t *off);
2706 static struct file_operations dressz_fops = {
2707         .open = sg_proc_single_open_dressz,
2708         .write = sg_proc_write_dressz,
2709         .release = single_release,
2710 };
2711
2712 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2713 static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2714 static struct file_operations version_fops = {
2715         .open = sg_proc_single_open_version,
2716         .release = single_release,
2717 };
2718
2719 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2720 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2721 static struct file_operations devhdr_fops = {
2722         .open = sg_proc_single_open_devhdr,
2723         .release = single_release,
2724 };
2725
2726 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2727 static int sg_proc_open_dev(struct inode *inode, struct file *file);
2728 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2729 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2730 static void dev_seq_stop(struct seq_file *s, void *v);
2731 static struct file_operations dev_fops = {
2732         .open = sg_proc_open_dev,
2733         .release = seq_release,
2734 };
2735 static struct seq_operations dev_seq_ops = {
2736         .start = dev_seq_start,
2737         .next  = dev_seq_next,
2738         .stop  = dev_seq_stop,
2739         .show  = sg_proc_seq_show_dev,
2740 };
2741
2742 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2743 static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2744 static struct file_operations devstrs_fops = {
2745         .open = sg_proc_open_devstrs,
2746         .release = seq_release,
2747 };
2748 static struct seq_operations devstrs_seq_ops = {
2749         .start = dev_seq_start,
2750         .next  = dev_seq_next,
2751         .stop  = dev_seq_stop,
2752         .show  = sg_proc_seq_show_devstrs,
2753 };
2754
2755 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2756 static int sg_proc_open_debug(struct inode *inode, struct file *file);
2757 static struct file_operations debug_fops = {
2758         .open = sg_proc_open_debug,
2759         .release = seq_release,
2760 };
2761 static struct seq_operations debug_seq_ops = {
2762         .start = dev_seq_start,
2763         .next  = dev_seq_next,
2764         .stop  = dev_seq_stop,
2765         .show  = sg_proc_seq_show_debug,
2766 };
2767
2768
2769 struct sg_proc_leaf {
2770         const char * name;
2771         struct file_operations * fops;
2772 };
2773
2774 static struct sg_proc_leaf sg_proc_leaf_arr[] = {
2775         {"allow_dio", &adio_fops},
2776         {"debug", &debug_fops},
2777         {"def_reserved_size", &dressz_fops},
2778         {"device_hdr", &devhdr_fops},
2779         {"devices", &dev_fops},
2780         {"device_strs", &devstrs_fops},
2781         {"version", &version_fops}
2782 };
2783
2784 static int
2785 sg_proc_init(void)
2786 {
2787         int k, mask;
2788         int num_leaves =
2789             sizeof (sg_proc_leaf_arr) / sizeof (sg_proc_leaf_arr[0]);
2790         struct proc_dir_entry *pdep;
2791         struct sg_proc_leaf * leaf;
2792
2793         sg_proc_sgp = create_proc_entry(sg_proc_sg_dirname,
2794                                         S_IFDIR | S_IRUGO | S_IXUGO, NULL);
2795         if (!sg_proc_sgp)
2796                 return 1;
2797         for (k = 0; k < num_leaves; ++k) {
2798                 leaf = &sg_proc_leaf_arr[k];
2799                 mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2800                 pdep = create_proc_entry(leaf->name, mask, sg_proc_sgp);
2801                 if (pdep) {
2802                         leaf->fops->owner = THIS_MODULE,
2803                         leaf->fops->read = seq_read,
2804                         leaf->fops->llseek = seq_lseek,
2805                         pdep->proc_fops = leaf->fops;
2806                 }
2807         }
2808         return 0;
2809 }
2810
2811 static void
2812 sg_proc_cleanup(void)
2813 {
2814         int k;
2815         int num_leaves =
2816             sizeof (sg_proc_leaf_arr) / sizeof (sg_proc_leaf_arr[0]);
2817
2818         if (!sg_proc_sgp)
2819                 return;
2820         for (k = 0; k < num_leaves; ++k)
2821                 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2822         remove_proc_entry(sg_proc_sg_dirname, NULL);
2823 }
2824
2825
2826 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2827 {
2828         seq_printf(s, "%d\n", *((int *)s->private));
2829         return 0;
2830 }
2831
2832 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2833 {
2834         return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2835 }
2836
2837 static ssize_t
2838 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2839                    size_t count, loff_t *off)
2840 {
2841         int num;
2842         char buff[11];
2843
2844         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2845                 return -EACCES;
2846         num = (count < 10) ? count : 10;
2847         if (copy_from_user(buff, buffer, num))
2848                 return -EFAULT;
2849         buff[num] = '\0';
2850         sg_allow_dio = simple_strtoul(buff, NULL, 10) ? 1 : 0;
2851         return count;
2852 }
2853
2854 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2855 {
2856         return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2857 }
2858
2859 static ssize_t
2860 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2861                      size_t count, loff_t *off)
2862 {
2863         int num;
2864         unsigned long k = ULONG_MAX;
2865         char buff[11];
2866
2867         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2868                 return -EACCES;
2869         num = (count < 10) ? count : 10;
2870         if (copy_from_user(buff, buffer, num))
2871                 return -EFAULT;
2872         buff[num] = '\0';
2873         k = simple_strtoul(buff, NULL, 10);
2874         if (k <= 1048576) {     /* limit "big buff" to 1 MB */
2875                 sg_big_buff = k;
2876                 return count;
2877         }
2878         return -ERANGE;
2879 }
2880
2881 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2882 {
2883         seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2884                    sg_version_date);
2885         return 0;
2886 }
2887
2888 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2889 {
2890         return single_open(file, sg_proc_seq_show_version, NULL);
2891 }
2892
2893 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2894 {
2895         seq_printf(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\t"
2896                    "online\n");
2897         return 0;
2898 }
2899
2900 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2901 {
2902         return single_open(file, sg_proc_seq_show_devhdr, NULL);
2903 }
2904
2905 struct sg_proc_deviter {
2906         loff_t  index;
2907         size_t  max;
2908 };
2909
2910 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2911 {
2912         struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2913
2914         if (! it)
2915                 return NULL;
2916         if (NULL == sg_dev_arr)
2917                 goto err1;
2918         it->index = *pos;
2919         it->max = sg_last_dev();
2920         if (it->index >= it->max)
2921                 goto err1;
2922         return it;
2923 err1:
2924         kfree(it);
2925         return NULL;
2926 }
2927
2928 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2929 {
2930         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2931
2932         *pos = ++it->index;
2933         return (it->index < it->max) ? it : NULL;
2934 }
2935
2936 static void dev_seq_stop(struct seq_file *s, void *v)
2937 {
2938         kfree (v);
2939 }
2940
2941 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2942 {
2943         return seq_open(file, &dev_seq_ops);
2944 }
2945
2946 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2947 {
2948         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2949         Sg_device *sdp;
2950         struct scsi_device *scsidp;
2951
2952         sdp = it ? sg_get_dev(it->index) : NULL;
2953         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2954                 seq_printf(s, "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n",
2955                               scsidp->host->host_no, scsidp->channel,
2956                               scsidp->id, scsidp->lun, (int) scsidp->type,
2957                               1,
2958                               (int) scsidp->queue_depth,
2959                               (int) scsidp->device_busy,
2960                               (int) scsi_device_online(scsidp));
2961         else
2962                 seq_printf(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2963         return 0;
2964 }
2965
2966 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2967 {
2968         return seq_open(file, &devstrs_seq_ops);
2969 }
2970
2971 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2972 {
2973         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2974         Sg_device *sdp;
2975         struct scsi_device *scsidp;
2976
2977         sdp = it ? sg_get_dev(it->index) : NULL;
2978         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2979                 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2980                            scsidp->vendor, scsidp->model, scsidp->rev);
2981         else
2982                 seq_printf(s, "<no active device>\n");
2983         return 0;
2984 }
2985
2986 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2987 {
2988         int k, m, new_interface, blen, usg;
2989         Sg_request *srp;
2990         Sg_fd *fp;
2991         const sg_io_hdr_t *hp;
2992         const char * cp;
2993
2994         for (k = 0; (fp = sg_get_nth_sfp(sdp, k)); ++k) {
2995                 seq_printf(s, "   FD(%d): timeout=%dms bufflen=%d "
2996                            "(res)sgat=%d low_dma=%d\n", k + 1,
2997                            jiffies_to_msecs(fp->timeout),
2998                            fp->reserve.bufflen,
2999                            (int) fp->reserve.k_use_sg,
3000                            (int) fp->low_dma);
3001                 seq_printf(s, "   cmd_q=%d f_packid=%d k_orphan=%d closed=%d\n",
3002                            (int) fp->cmd_q, (int) fp->force_packid,
3003                            (int) fp->keep_orphan, (int) fp->closed);
3004                 for (m = 0; (srp = sg_get_nth_request(fp, m)); ++m) {
3005                         hp = &srp->header;
3006                         new_interface = (hp->interface_id == '\0') ? 0 : 1;
3007                         if (srp->res_used) {
3008                                 if (new_interface &&
3009                                     (SG_FLAG_MMAP_IO & hp->flags))
3010                                         cp = "     mmap>> ";
3011                                 else
3012                                         cp = "     rb>> ";
3013                         } else {
3014                                 if (SG_INFO_DIRECT_IO_MASK & hp->info)
3015                                         cp = "     dio>> ";
3016                                 else
3017                                         cp = "     ";
3018                         }
3019                         seq_printf(s, cp);
3020                         blen = srp->my_cmdp ?
3021                                 srp->my_cmdp->sr_bufflen : srp->data.bufflen;
3022                         usg = srp->my_cmdp ?
3023                                 srp->my_cmdp->sr_use_sg : srp->data.k_use_sg;
3024                         seq_printf(s, srp->done ?
3025                                    ((1 == srp->done) ?  "rcv:" : "fin:")
3026                                    : (srp->my_cmdp ? "act:" : "prior:"));
3027                         seq_printf(s, " id=%d blen=%d",
3028                                    srp->header.pack_id, blen);
3029                         if (srp->done)
3030                                 seq_printf(s, " dur=%d", hp->duration);
3031                         else
3032                                 seq_printf(s, " t_o/elap=%d/%d",
3033                                   new_interface ? hp->timeout : jiffies_to_msecs(fp->timeout),
3034                                   jiffies_to_msecs(hp->duration ? (jiffies - hp->duration) : 0));
3035                         seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
3036                                    (int) srp->data.cmd_opcode);
3037                 }
3038                 if (0 == m)
3039                         seq_printf(s, "     No requests active\n");
3040         }
3041 }
3042
3043 static int sg_proc_open_debug(struct inode *inode, struct file *file)
3044 {
3045         return seq_open(file, &debug_seq_ops);
3046 }
3047
3048 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
3049 {
3050         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
3051         Sg_device *sdp;
3052
3053         if (it && (0 == it->index)) {
3054                 seq_printf(s, "dev_max(currently)=%d max_active_device=%d "
3055                            "(origin 1)\n", sg_dev_max, (int)it->max);
3056                 seq_printf(s, " def_reserved_size=%d\n", sg_big_buff);
3057         }
3058         sdp = it ? sg_get_dev(it->index) : NULL;
3059         if (sdp) {
3060                 struct scsi_device *scsidp = sdp->device;
3061
3062                 if (NULL == scsidp) {
3063                         seq_printf(s, "device %d detached ??\n",
3064                                    (int)it->index);
3065                         return 0;
3066                 }
3067
3068                 if (sg_get_nth_sfp(sdp, 0)) {
3069                         seq_printf(s, " >>> device=%s ",
3070                                 sdp->disk->disk_name);
3071                         if (sdp->detached)
3072                                 seq_printf(s, "detached pending close ");
3073                         else
3074                                 seq_printf
3075                                     (s, "scsi%d chan=%d id=%d lun=%d   em=%d",
3076                                      scsidp->host->host_no,
3077                                      scsidp->channel, scsidp->id,
3078                                      scsidp->lun,
3079                                      scsidp->host->hostt->emulated);
3080                         seq_printf(s, " sg_tablesize=%d excl=%d\n",
3081                                    sdp->sg_tablesize, sdp->exclude);
3082                 }
3083                 sg_proc_debug_helper(s, sdp);
3084         }
3085         return 0;
3086 }
3087
3088 #endif                          /* CONFIG_SCSI_PROC_FS */
3089
3090 module_init(init_sg);
3091 module_exit(exit_sg);
3092 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);