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 - 2004 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 = 30531;      /* 2 digits for each component */
  22 #define SG_VERSION_STR "3.5.31"
  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 = "20040516";
  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 rwlock_t sg_dev_arr_lock = RW_LOCK_UNLOCKED;     /* 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 k, 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 ((k = verify_area(VERIFY_WRITE, buf, count)))
 347                 return k;
 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 ((k = verify_area(VERIFY_READ, buf, count)))
 505                 return k;       /* 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         k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
 567         return (k < 0) ? k : count;
 568 }
 569
 570 static ssize_t
 571 sg_new_write(Sg_fd * sfp, const char __user *buf, size_t count,
 572              int blocking, int read_only, Sg_request ** o_srp)
 573 {
 574         int k;
 575         Sg_request *srp;
 576         sg_io_hdr_t *hp;
 577         unsigned char cmnd[sizeof (dummy_cmdp->sr_cmnd)];
 578         int timeout;
 579
 580         if (count < SZ_SG_IO_HDR)
 581                 return -EINVAL;
 582         if ((k = verify_area(VERIFY_READ, buf, count)))
 583                 return k; /* protects following copy_from_user()s + get_user()s */
 584
 585         sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
 586         if (!(srp = sg_add_request(sfp))) {
 587                 SCSI_LOG_TIMEOUT(1, printk("sg_new_write: queue full\n"));
 588                 return -EDOM;
 589         }
 590         hp = &srp->header;
 591         if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
 592                 sg_remove_request(sfp, srp);
 593                 return -EFAULT;
 594         }
 595         if (hp->interface_id != 'S') {
 596                 sg_remove_request(sfp, srp);
 597                 return -ENOSYS;
 598         }
 599         if (hp->flags & SG_FLAG_MMAP_IO) {
 600                 if (hp->dxfer_len > sfp->reserve.bufflen) {
 601                         sg_remove_request(sfp, srp);
 602                         return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
 603                 }
 604                 if (hp->flags & SG_FLAG_DIRECT_IO) {
 605                         sg_remove_request(sfp, srp);
 606                         return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
 607                 }
 608                 if (sg_res_in_use(sfp)) {
 609                         sg_remove_request(sfp, srp);
 610                         return -EBUSY;  /* reserve buffer already being used */
 611                 }
 612         }
 613         timeout = msecs_to_jiffies(srp->header.timeout);
 614         if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
 615                 sg_remove_request(sfp, srp);
 616                 return -EMSGSIZE;
 617         }
 618         if ((k = verify_area(VERIFY_READ, hp->cmdp, hp->cmd_len))) {
 619                 sg_remove_request(sfp, srp);
 620                 return k;       /* protects following copy_from_user()s + get_user()s */
 621         }
 622         if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
 623                 sg_remove_request(sfp, srp);
 624                 return -EFAULT;
 625         }
 626         if (read_only &&
 627             (!sg_allow_access(cmnd[0], sfp->parentdp->device->type))) {
 628                 sg_remove_request(sfp, srp);
 629                 return -EPERM;
 630         }
 631         k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
 632         if (k < 0)
 633                 return k;
 634         if (o_srp)
 635                 *o_srp = srp;
 636         return count;
 637 }
 638
 639 static int
 640 sg_common_write(Sg_fd * sfp, Sg_request * srp,
 641                 unsigned char *cmnd, int timeout, int blocking)
 642 {
 643         int k;
 644         Scsi_Request *SRpnt;
 645         Sg_device *sdp = sfp->parentdp;
 646         sg_io_hdr_t *hp = &srp->header;
 647         request_queue_t *q;
 648
 649         srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
 650         hp->status = 0;
 651         hp->masked_status = 0;
 652         hp->msg_status = 0;
 653         hp->info = 0;
 654         hp->host_status = 0;
 655         hp->driver_status = 0;
 656         hp->resid = 0;
 657         SCSI_LOG_TIMEOUT(4, printk("sg_common_write:  scsi opcode=0x%02x, cmd_size=%d\n",
 658                           (int) cmnd[0], (int) hp->cmd_len));
 659
 660         if ((k = sg_start_req(srp))) {
 661                 SCSI_LOG_TIMEOUT(1, printk("sg_write: start_req err=%d\n", k));
 662                 sg_finish_rem_req(srp);
 663                 return k;       /* probably out of space --> ENOMEM */
 664         }
 665         if ((k = sg_write_xfer(srp))) {
 666                 SCSI_LOG_TIMEOUT(1, printk("sg_write: write_xfer, bad address\n"));
 667                 sg_finish_rem_req(srp);
 668                 return k;
 669         }
 670         if (sdp->detached) {
 671                 sg_finish_rem_req(srp);
 672                 return -ENODEV;
 673         }
 674         SRpnt = scsi_allocate_request(sdp->device, GFP_ATOMIC);
 675         if (SRpnt == NULL) {
 676                 SCSI_LOG_TIMEOUT(1, printk("sg_write: no mem\n"));
 677                 sg_finish_rem_req(srp);
 678                 return -ENOMEM;
 679         }
 680
 681         srp->my_cmdp = SRpnt;
 682         q = SRpnt->sr_device->request_queue;
 683         SRpnt->sr_request->rq_disk = sdp->disk;
 684         SRpnt->sr_sense_buffer[0] = 0;
 685         SRpnt->sr_cmd_len = hp->cmd_len;
 686         SRpnt->sr_use_sg = srp->data.k_use_sg;
 687         SRpnt->sr_sglist_len = srp->data.sglist_len;
 688         SRpnt->sr_bufflen = srp->data.bufflen;
 689         SRpnt->sr_underflow = 0;
 690         SRpnt->sr_buffer = srp->data.buffer;
 691         switch (hp->dxfer_direction) {
 692         case SG_DXFER_TO_FROM_DEV:
 693         case SG_DXFER_FROM_DEV:
 694                 SRpnt->sr_data_direction = SCSI_DATA_READ;
 695                 break;
 696         case SG_DXFER_TO_DEV:
 697                 SRpnt->sr_data_direction = SCSI_DATA_WRITE;
 698                 break;
 699         case SG_DXFER_UNKNOWN:
 700                 SRpnt->sr_data_direction = SCSI_DATA_UNKNOWN;
 701                 break;
 702         default:
 703                 SRpnt->sr_data_direction = SCSI_DATA_NONE;
 704                 break;
 705         }
 706         SRpnt->upper_private_data = srp;
 707         srp->data.k_use_sg = 0;
 708         srp->data.sglist_len = 0;
 709         srp->data.bufflen = 0;
 710         srp->data.buffer = NULL;
 711         hp->duration = jiffies; /* unit jiffies now, millisecs after done */
 712 /* Now send everything of to mid-level. The next time we hear about this
 713    packet is when sg_cmd_done() is called (i.e. a callback). */
 714         scsi_do_req(SRpnt, (void *) cmnd,
 715                     (void *) SRpnt->sr_buffer, hp->dxfer_len,
 716                     sg_cmd_done, timeout, SG_DEFAULT_RETRIES);
 717         /* dxfer_len overwrites SRpnt->sr_bufflen, hence need for b_malloc_len */
 718         return 0;
 719 }
 720
 721 static int
 722 sg_ioctl(struct inode *inode, struct file *filp,
 723          unsigned int cmd_in, unsigned long arg)
 724 {
 725         void __user *p = (void __user *)arg;
 726         int __user *ip = p;
 727         int result, val, read_only;
 728         Sg_device *sdp;
 729         Sg_fd *sfp;
 730         Sg_request *srp;
 731         unsigned long iflags;
 732
 733         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 734                 return -ENXIO;
 735         SCSI_LOG_TIMEOUT(3, printk("sg_ioctl: %s, cmd=0x%x\n",
 736                                    sdp->disk->disk_name, (int) cmd_in));
 737         read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
 738
 739         switch (cmd_in) {
 740         case SG_IO:
 741                 {
 742                         int blocking = 1;       /* ignore O_NONBLOCK flag */
 743
 744                         if (sdp->detached)
 745                                 return -ENODEV;
 746                         if (!scsi_block_when_processing_errors(sdp->device))
 747                                 return -ENXIO;
 748                         result = verify_area(VERIFY_WRITE, p, SZ_SG_IO_HDR);
 749                         if (result)
 750                                 return result;
 751                         result =
 752                             sg_new_write(sfp, p, SZ_SG_IO_HDR,
 753                                          blocking, read_only, &srp);
 754                         if (result < 0)
 755                                 return result;
 756                         srp->sg_io_owned = 1;
 757                         while (1) {
 758                                 result = 0;     /* following macro to beat race condition */
 759                                 __wait_event_interruptible(sfp->read_wait,
 760                                         (sdp->detached || sfp->closed || srp->done),
 761                                                            result);
 762                                 if (sdp->detached)
 763                                         return -ENODEV;
 764                                 if (sfp->closed)
 765                                         return 0;       /* request packet dropped already */
 766                                 if (0 == result)
 767                                         break;
 768                                 srp->orphan = 1;
 769                                 return result;  /* -ERESTARTSYS because signal hit process */
 770                         }
 771                         srp->done = 2;
 772                         result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
 773                         return (result < 0) ? result : 0;
 774                 }
 775         case SG_SET_TIMEOUT:
 776                 result = get_user(val, ip);
 777                 if (result)
 778                         return result;
 779                 if (val < 0)
 780                         return -EIO;
 781                 if (val >= MULDIV (INT_MAX, USER_HZ, HZ))
 782                     val = MULDIV (INT_MAX, USER_HZ, HZ);
 783                 sfp->timeout_user = val;
 784                 sfp->timeout = MULDIV (val, HZ, USER_HZ);
 785
 786                 return 0;
 787         case SG_GET_TIMEOUT:    /* N.B. User receives timeout as return value */
 788                                 /* strange ..., for backward compatibility */
 789                 return sfp->timeout_user;
 790         case SG_SET_FORCE_LOW_DMA:
 791                 result = get_user(val, ip);
 792                 if (result)
 793                         return result;
 794                 if (val) {
 795                         sfp->low_dma = 1;
 796                         if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
 797                                 val = (int) sfp->reserve.bufflen;
 798                                 sg_remove_scat(&sfp->reserve);
 799                                 sg_build_reserve(sfp, val);
 800                         }
 801                 } else {
 802                         if (sdp->detached)
 803                                 return -ENODEV;
 804                         sfp->low_dma = sdp->device->host->unchecked_isa_dma;
 805                 }
 806                 return 0;
 807         case SG_GET_LOW_DMA:
 808                 return put_user((int) sfp->low_dma, ip);
 809         case SG_GET_SCSI_ID:
 810                 result =
 811                     verify_area(VERIFY_WRITE, p, sizeof (sg_scsi_id_t));
 812                 if (result)
 813                         return result;
 814                 else {
 815                         sg_scsi_id_t __user *sg_idp = p;
 816
 817                         if (sdp->detached)
 818                                 return -ENODEV;
 819                         __put_user((int) sdp->device->host->host_no,
 820                                    &sg_idp->host_no);
 821                         __put_user((int) sdp->device->channel,
 822                                    &sg_idp->channel);
 823                         __put_user((int) sdp->device->id, &sg_idp->scsi_id);
 824                         __put_user((int) sdp->device->lun, &sg_idp->lun);
 825                         __put_user((int) sdp->device->type, &sg_idp->scsi_type);
 826                         __put_user((short) sdp->device->host->cmd_per_lun,
 827                                    &sg_idp->h_cmd_per_lun);
 828                         __put_user((short) sdp->device->queue_depth,
 829                                    &sg_idp->d_queue_depth);
 830                         __put_user(0, &sg_idp->unused[0]);
 831                         __put_user(0, &sg_idp->unused[1]);
 832                         return 0;
 833                 }
 834         case SG_SET_FORCE_PACK_ID:
 835                 result = get_user(val, ip);
 836                 if (result)
 837                         return result;
 838                 sfp->force_packid = val ? 1 : 0;
 839                 return 0;
 840         case SG_GET_PACK_ID:
 841                 result = verify_area(VERIFY_WRITE, ip, sizeof (int));
 842                 if (result)
 843                         return result;
 844                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 845                 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
 846                         if ((1 == srp->done) && (!srp->sg_io_owned)) {
 847                                 read_unlock_irqrestore(&sfp->rq_list_lock,
 848                                                        iflags);
 849                                 __put_user(srp->header.pack_id, ip);
 850                                 return 0;
 851                         }
 852                 }
 853                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 854                 __put_user(-1, ip);
 855                 return 0;
 856         case SG_GET_NUM_WAITING:
 857                 read_lock_irqsave(&sfp->rq_list_lock, iflags);
 858                 for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) {
 859                         if ((1 == srp->done) && (!srp->sg_io_owned))
 860                                 ++val;
 861                 }
 862                 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 863                 return put_user(val, ip);
 864         case SG_GET_SG_TABLESIZE:
 865                 return put_user(sdp->sg_tablesize, ip);
 866         case SG_SET_RESERVED_SIZE:
 867                 result = get_user(val, ip);
 868                 if (result)
 869                         return result;
 870                 if (val < 0)
 871                         return -EINVAL;
 872                 if (val != sfp->reserve.bufflen) {
 873                         if (sg_res_in_use(sfp) || sfp->mmap_called)
 874                                 return -EBUSY;
 875                         sg_remove_scat(&sfp->reserve);
 876                         sg_build_reserve(sfp, val);
 877                 }
 878                 return 0;
 879         case SG_GET_RESERVED_SIZE:
 880                 val = (int) sfp->reserve.bufflen;
 881                 return put_user(val, ip);
 882         case SG_SET_COMMAND_Q:
 883                 result = get_user(val, ip);
 884                 if (result)
 885                         return result;
 886                 sfp->cmd_q = val ? 1 : 0;
 887                 return 0;
 888         case SG_GET_COMMAND_Q:
 889                 return put_user((int) sfp->cmd_q, ip);
 890         case SG_SET_KEEP_ORPHAN:
 891                 result = get_user(val, ip);
 892                 if (result)
 893                         return result;
 894                 sfp->keep_orphan = val;
 895                 return 0;
 896         case SG_GET_KEEP_ORPHAN:
 897                 return put_user((int) sfp->keep_orphan, ip);
 898         case SG_NEXT_CMD_LEN:
 899                 result = get_user(val, ip);
 900                 if (result)
 901                         return result;
 902                 sfp->next_cmd_len = (val > 0) ? val : 0;
 903                 return 0;
 904         case SG_GET_VERSION_NUM:
 905                 return put_user(sg_version_num, ip);
 906         case SG_GET_ACCESS_COUNT:
 907                 /* faked - we don't have a real access count anymore */
 908                 val = (sdp->device ? 1 : 0);
 909                 return put_user(val, ip);
 910         case SG_GET_REQUEST_TABLE:
 911                 result = verify_area(VERIFY_WRITE, p,
 912                                      SZ_SG_REQ_INFO * SG_MAX_QUEUE);
 913                 if (result)
 914                         return result;
 915                 else {
 916                         sg_req_info_t rinfo[SG_MAX_QUEUE];
 917                         Sg_request *srp;
 918                         read_lock_irqsave(&sfp->rq_list_lock, iflags);
 919                         for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE;
 920                              ++val, srp = srp ? srp->nextrp : srp) {
 921                                 memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
 922                                 if (srp) {
 923                                         rinfo[val].req_state = srp->done + 1;
 924                                         rinfo[val].problem =
 925                                             srp->header.masked_status &
 926                                             srp->header.host_status &
 927                                             srp->header.driver_status;
 928                                         rinfo[val].duration =
 929                                             srp->done ? srp->header.duration :
 930                                             jiffies_to_msecs(
 931                                                 jiffies - srp->header.duration);
 932                                         rinfo[val].orphan = srp->orphan;
 933                                         rinfo[val].sg_io_owned = srp->sg_io_owned;
 934                                         rinfo[val].pack_id = srp->header.pack_id;
 935                                         rinfo[val].usr_ptr = srp->header.usr_ptr;
 936                                 }
 937                         }
 938                         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 939                         return (__copy_to_user(p, rinfo,
 940                                 SZ_SG_REQ_INFO * SG_MAX_QUEUE) ? -EFAULT : 0);
 941                 }
 942         case SG_EMULATED_HOST:
 943                 if (sdp->detached)
 944                         return -ENODEV;
 945                 return put_user(sdp->device->host->hostt->emulated, ip);
 946         case SG_SCSI_RESET:
 947                 if (sdp->detached)
 948                         return -ENODEV;
 949                 if (filp->f_flags & O_NONBLOCK) {
 950                         if (test_bit(SHOST_RECOVERY,
 951                                      &sdp->device->host->shost_state))
 952                                 return -EBUSY;
 953                 } else if (!scsi_block_when_processing_errors(sdp->device))
 954                         return -EBUSY;
 955                 result = get_user(val, ip);
 956                 if (result)
 957                         return result;
 958                 if (SG_SCSI_RESET_NOTHING == val)
 959                         return 0;
 960                 switch (val) {
 961                 case SG_SCSI_RESET_DEVICE:
 962                         val = SCSI_TRY_RESET_DEVICE;
 963                         break;
 964                 case SG_SCSI_RESET_BUS:
 965                         val = SCSI_TRY_RESET_BUS;
 966                         break;
 967                 case SG_SCSI_RESET_HOST:
 968                         val = SCSI_TRY_RESET_HOST;
 969                         break;
 970                 default:
 971                         return -EINVAL;
 972                 }
 973                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
 974                         return -EACCES;
 975                 return (scsi_reset_provider(sdp->device, val) ==
 976                         SUCCESS) ? 0 : -EIO;
 977         case SCSI_IOCTL_SEND_COMMAND:
 978                 if (sdp->detached)
 979                         return -ENODEV;
 980                 if (read_only) {
 981                         unsigned char opcode = WRITE_6;
 982                         Scsi_Ioctl_Command __user *siocp = p;
 983
 984                         if (copy_from_user(&opcode, siocp->data, 1))
 985                                 return -EFAULT;
 986                         if (!sg_allow_access(opcode, sdp->device->type))
 987                                 return -EPERM;
 988                 }
 989                 return scsi_ioctl_send_command(sdp->device, p);
 990         case SG_SET_DEBUG:
 991                 result = get_user(val, ip);
 992                 if (result)
 993                         return result;
 994                 sdp->sgdebug = (char) val;
 995                 return 0;
 996         case SCSI_IOCTL_GET_IDLUN:
 997         case SCSI_IOCTL_GET_BUS_NUMBER:
 998         case SCSI_IOCTL_PROBE_HOST:
 999         case SG_GET_TRANSFORM:
1000                 if (sdp->detached)
1001                         return -ENODEV;
1002                 return scsi_ioctl(sdp->device, cmd_in, p);
1003         default:
1004                 if (read_only)
1005                         return -EPERM;  /* don't know so take safe approach */
1006                 return scsi_ioctl(sdp->device, cmd_in, p);
1007         }
1008 }
1009
1010 static unsigned int
1011 sg_poll(struct file *filp, poll_table * wait)
1012 {
1013         unsigned int res = 0;
1014         Sg_device *sdp;
1015         Sg_fd *sfp;
1016         Sg_request *srp;
1017         int count = 0;
1018         unsigned long iflags;
1019
1020         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))
1021             || sfp->closed)
1022                 return POLLERR;
1023         poll_wait(filp, &sfp->read_wait, wait);
1024         read_lock_irqsave(&sfp->rq_list_lock, iflags);
1025         for (srp = sfp->headrp; srp; srp = srp->nextrp) {
1026                 /* if any read waiting, flag it */
1027                 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1028                         res = POLLIN | POLLRDNORM;
1029                 ++count;
1030         }
1031         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1032
1033         if (sdp->detached)
1034                 res |= POLLHUP;
1035         else if (!sfp->cmd_q) {
1036                 if (0 == count)
1037                         res |= POLLOUT | POLLWRNORM;
1038         } else if (count < SG_MAX_QUEUE)
1039                 res |= POLLOUT | POLLWRNORM;
1040         SCSI_LOG_TIMEOUT(3, printk("sg_poll: %s, res=0x%x\n",
1041                                    sdp->disk->disk_name, (int) res));
1042         return res;
1043 }
1044
1045 static int
1046 sg_fasync(int fd, struct file *filp, int mode)
1047 {
1048         int retval;
1049         Sg_device *sdp;
1050         Sg_fd *sfp;
1051
1052         if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1053                 return -ENXIO;
1054         SCSI_LOG_TIMEOUT(3, printk("sg_fasync: %s, mode=%d\n",
1055                                    sdp->disk->disk_name, mode));
1056
1057         retval = fasync_helper(fd, filp, mode, &sfp->async_qp);
1058         return (retval < 0) ? retval : 0;
1059 }
1060
1061 static inline unsigned char *
1062 sg_scatg2virt(const struct scatterlist *sclp)
1063 {
1064         return (sclp && sclp->page) ?
1065             (unsigned char *) page_address(sclp->page) + sclp->offset : NULL;
1066 }
1067
1068 /* When startFinish==1 increments page counts for pages other than the
1069    first of scatter gather elements obtained from __get_free_pages().
1070    When startFinish==0 decrements ... */
1071 static void
1072 sg_rb_correct4mmap(Sg_scatter_hold * rsv_schp, int startFinish)
1073 {
1074         void *page_ptr;
1075         struct page *page;
1076         int k, m;
1077
1078         SCSI_LOG_TIMEOUT(3, printk("sg_rb_correct4mmap: startFinish=%d, scatg=%d\n",
1079                                    startFinish, rsv_schp->k_use_sg));
1080         /* N.B. correction _not_ applied to base page of each allocation */
1081         if (rsv_schp->k_use_sg) {       /* reserve buffer is a scatter gather list */
1082                 struct scatterlist *sclp = rsv_schp->buffer;
1083
1084                 for (k = 0; k < rsv_schp->k_use_sg; ++k, ++sclp) {
1085                         for (m = PAGE_SIZE; m < sclp->length; m += PAGE_SIZE) {
1086                                 page_ptr = sg_scatg2virt(sclp) + m;
1087                                 page = virt_to_page(page_ptr);
1088                                 if (startFinish)
1089                                         get_page(page);
1090                                 else {
1091                                         if (page_count(page) > 0)
1092                                                 __put_page(page);
1093                                 }
1094                         }
1095                 }
1096         } else {                /* reserve buffer is just a single allocation */
1097                 for (m = PAGE_SIZE; m < rsv_schp->bufflen; m += PAGE_SIZE) {
1098                         page_ptr = (unsigned char *) rsv_schp->buffer + m;
1099                         page = virt_to_page(page_ptr);
1100                         if (startFinish)
1101                                 get_page(page);
1102                         else {
1103                                 if (page_count(page) > 0)
1104                                         __put_page(page);
1105                         }
1106                 }
1107         }
1108 }
1109
1110 static struct page *
1111 sg_vma_nopage(struct vm_area_struct *vma, unsigned long addr, int *type)
1112 {
1113         Sg_fd *sfp;
1114         struct page *page = NOPAGE_SIGBUS;
1115         void *page_ptr = NULL;
1116         unsigned long offset;
1117         Sg_scatter_hold *rsv_schp;
1118
1119         if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1120                 return page;
1121         rsv_schp = &sfp->reserve;
1122         offset = addr - vma->vm_start;
1123         if (offset >= rsv_schp->bufflen)
1124                 return page;
1125         SCSI_LOG_TIMEOUT(3, printk("sg_vma_nopage: offset=%lu, scatg=%d\n",
1126                                    offset, rsv_schp->k_use_sg));
1127         if (rsv_schp->k_use_sg) {       /* reserve buffer is a scatter gather list */
1128                 int k;
1129                 unsigned long sa = vma->vm_start;
1130                 unsigned long len;
1131                 struct scatterlist *sclp = rsv_schp->buffer;
1132
1133                 for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
1134                      ++k, ++sclp) {
1135                         len = vma->vm_end - sa;
1136                         len = (len < sclp->length) ? len : sclp->length;
1137                         if (offset < len) {
1138                                 page_ptr = sg_scatg2virt(sclp) + offset;
1139                                 page = virt_to_page(page_ptr);
1140                                 get_page(page); /* increment page count */
1141                                 break;
1142                         }
1143                         sa += len;
1144                         offset -= len;
1145                 }
1146         } else {                /* reserve buffer is just a single allocation */
1147                 page_ptr = (unsigned char *) rsv_schp->buffer + offset;
1148                 page = virt_to_page(page_ptr);
1149                 get_page(page); /* increment page count */
1150         }
1151         if (type)
1152                 *type = VM_FAULT_MINOR;
1153         return page;
1154 }
1155
1156 static struct vm_operations_struct sg_mmap_vm_ops = {
1157         .nopage = sg_vma_nopage,
1158 };
1159
1160 static int
1161 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1162 {
1163         Sg_fd *sfp;
1164         unsigned long req_sz = vma->vm_end - vma->vm_start;
1165         Sg_scatter_hold *rsv_schp;
1166
1167         if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1168                 return -ENXIO;
1169         SCSI_LOG_TIMEOUT(3, printk("sg_mmap starting, vm_start=%p, len=%d\n",
1170                                    (void *) vma->vm_start, (int) req_sz));
1171         if (vma->vm_pgoff)
1172                 return -EINVAL; /* want no offset */
1173         rsv_schp = &sfp->reserve;
1174         if (req_sz > rsv_schp->bufflen)
1175                 return -ENOMEM; /* cannot map more than reserved buffer */
1176
1177         if (rsv_schp->k_use_sg) { /* reserve buffer is a scatter gather list */
1178                 int k;
1179                 unsigned long sa = vma->vm_start;
1180                 unsigned long len;
1181                 struct scatterlist *sclp = rsv_schp->buffer;
1182
1183                 for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
1184                      ++k, ++sclp) {
1185                         if (0 != sclp->offset)
1186                                 return -EFAULT; /* non page aligned memory ?? */
1187                         len = vma->vm_end - sa;
1188                         len = (len < sclp->length) ? len : sclp->length;
1189                         sa += len;
1190                 }
1191         } else {        /* reserve buffer is just a single allocation */
1192                 if ((unsigned long) rsv_schp->buffer & (PAGE_SIZE - 1))
1193                         return -EFAULT; /* non page aligned memory ?? */
1194         }
1195         if (0 == sfp->mmap_called) {
1196                 sg_rb_correct4mmap(rsv_schp, 1);        /* do only once per fd lifetime */
1197                 sfp->mmap_called = 1;
1198         }
1199         vma->vm_flags |= (VM_RESERVED | VM_IO);
1200         vma->vm_private_data = sfp;
1201         vma->vm_ops = &sg_mmap_vm_ops;
1202         return 0;
1203 }
1204
1205 /* This function is a "bottom half" handler that is called by the
1206  * mid level when a command is completed (or has failed). */
1207 static void
1208 sg_cmd_done(Scsi_Cmnd * SCpnt)
1209 {
1210         Scsi_Request *SRpnt = NULL;
1211         Sg_device *sdp = NULL;
1212         Sg_fd *sfp;
1213         Sg_request *srp = NULL;
1214
1215         if (SCpnt && (SRpnt = SCpnt->sc_request))
1216                 srp = (Sg_request *) SRpnt->upper_private_data;
1217         if (NULL == srp) {
1218                 printk(KERN_ERR "sg_cmd_done: NULL request\n");
1219                 if (SRpnt)
1220                         scsi_release_request(SRpnt);
1221                 return;
1222         }
1223         sfp = srp->parentfp;
1224         if (sfp)
1225                 sdp = sfp->parentdp;
1226         if ((NULL == sdp) || sdp->detached) {
1227                 printk(KERN_INFO "sg_cmd_done: device detached\n");
1228                 scsi_release_request(SRpnt);
1229                 return;
1230         }
1231
1232         /* First transfer ownership of data buffers to sg_device object. */
1233         srp->data.k_use_sg = SRpnt->sr_use_sg;
1234         srp->data.sglist_len = SRpnt->sr_sglist_len;
1235         srp->data.bufflen = SRpnt->sr_bufflen;
1236         srp->data.buffer = SRpnt->sr_buffer;
1237         /* now clear out request structure */
1238         SRpnt->sr_use_sg = 0;
1239         SRpnt->sr_sglist_len = 0;
1240         SRpnt->sr_bufflen = 0;
1241         SRpnt->sr_buffer = NULL;
1242         SRpnt->sr_underflow = 0;
1243         SRpnt->sr_request->rq_disk = NULL; /* "sg" _disowns_ request blk */
1244
1245         srp->my_cmdp = NULL;
1246
1247         SCSI_LOG_TIMEOUT(4, printk("sg_cmd_done: %s, pack_id=%d, res=0x%x\n",
1248                 sdp->disk->disk_name, srp->header.pack_id, (int) SRpnt->sr_result));
1249         srp->header.resid = SCpnt->resid;
1250         /* N.B. unit of duration changes here from jiffies to millisecs */
1251         srp->header.duration =
1252             jiffies_to_msecs(jiffies - srp->header.duration);
1253         if (0 != SRpnt->sr_result) {
1254                 memcpy(srp->sense_b, SRpnt->sr_sense_buffer,
1255                        sizeof (srp->sense_b));
1256                 srp->header.status = 0xff & SRpnt->sr_result;
1257                 srp->header.masked_status = status_byte(SRpnt->sr_result);
1258                 srp->header.msg_status = msg_byte(SRpnt->sr_result);
1259                 srp->header.host_status = host_byte(SRpnt->sr_result);
1260                 srp->header.driver_status = driver_byte(SRpnt->sr_result);
1261                 if ((sdp->sgdebug > 0) &&
1262                     ((CHECK_CONDITION == srp->header.masked_status) ||
1263                      (COMMAND_TERMINATED == srp->header.masked_status)))
1264                         print_req_sense("sg_cmd_done", SRpnt);
1265
1266                 /* Following if statement is a patch supplied by Eric Youngdale */
1267                 if (driver_byte(SRpnt->sr_result) != 0
1268                     && (SRpnt->sr_sense_buffer[0] & 0x7f) == 0x70
1269                     && (SRpnt->sr_sense_buffer[2] & 0xf) == UNIT_ATTENTION
1270                     && sdp->device->removable) {
1271                         /* Detected disc change. Set the bit - this may be used if */
1272                         /* there are filesystems using this device. */
1273                         sdp->device->changed = 1;
1274                 }
1275         }
1276         /* Rely on write phase to clean out srp status values, so no "else" */
1277
1278         scsi_release_request(SRpnt);
1279         SRpnt = NULL;
1280         if (sfp->closed) {      /* whoops this fd already released, cleanup */
1281                 SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, freeing ...\n"));
1282                 sg_finish_rem_req(srp);
1283                 srp = NULL;
1284                 if (NULL == sfp->headrp) {
1285                         SCSI_LOG_TIMEOUT(1, printk("sg...bh: already closed, final cleanup\n"));
1286                         if (0 == sg_remove_sfp(sdp, sfp)) {     /* device still present */
1287                                 scsi_device_put(sdp->device);
1288                         }
1289                         sfp = NULL;
1290                 }
1291         } else if (srp && srp->orphan) {
1292                 if (sfp->keep_orphan)
1293                         srp->sg_io_owned = 0;
1294                 else {
1295                         sg_finish_rem_req(srp);
1296                         srp = NULL;
1297                 }
1298         }
1299         if (sfp && srp) {
1300                 /* Now wake up any sg_read() that is waiting for this packet. */
1301                 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1302                 srp->done = 1;
1303                 wake_up_interruptible(&sfp->read_wait);
1304         }
1305 }
1306
1307 static struct file_operations sg_fops = {
1308         .owner = THIS_MODULE,
1309         .read = sg_read,
1310         .write = sg_write,
1311         .poll = sg_poll,
1312         .ioctl = sg_ioctl,
1313         .open = sg_open,
1314         .mmap = sg_mmap,
1315         .release = sg_release,
1316         .fasync = sg_fasync,
1317 };
1318
1319 static struct class_simple * sg_sysfs_class;
1320
1321 static int sg_sysfs_valid = 0;
1322
1323 static int sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1324 {
1325         Sg_device *sdp;
1326         unsigned long iflags;
1327         void *old_sg_dev_arr = NULL;
1328         int k, error;
1329
1330         sdp = kmalloc(sizeof(Sg_device), GFP_KERNEL);
1331         if (!sdp) {
1332                 printk(KERN_WARNING "kmalloc Sg_device failure\n");
1333                 return -ENOMEM;
1334         }
1335
1336         write_lock_irqsave(&sg_dev_arr_lock, iflags);
1337         if (unlikely(sg_nr_dev >= sg_dev_max)) {        /* try to resize */
1338                 Sg_device **tmp_da;
1339                 int tmp_dev_max = sg_nr_dev + SG_DEV_ARR_LUMP;
1340                 write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1341
1342                 tmp_da = kmalloc(tmp_dev_max * sizeof(Sg_device *), GFP_KERNEL);
1343                 if (unlikely(!tmp_da))
1344                         goto expand_failed;
1345
1346                 write_lock_irqsave(&sg_dev_arr_lock, iflags);
1347                 memset(tmp_da, 0, tmp_dev_max * sizeof(Sg_device *));
1348                 memcpy(tmp_da, sg_dev_arr, sg_dev_max * sizeof(Sg_device *));
1349                 old_sg_dev_arr = sg_dev_arr;
1350                 sg_dev_arr = tmp_da;
1351                 sg_dev_max = tmp_dev_max;
1352         }
1353
1354         for (k = 0; k < sg_dev_max; k++)
1355                 if (!sg_dev_arr[k])
1356                         break;
1357         if (unlikely(k >= SG_MAX_DEVS))
1358                 goto overflow;
1359
1360         memset(sdp, 0, sizeof(*sdp));
1361         SCSI_LOG_TIMEOUT(3, printk("sg_alloc: dev=%d \n", k));
1362         sprintf(disk->disk_name, "sg%d", k);
1363         disk->first_minor = k;
1364         sdp->disk = disk;
1365         sdp->device = scsidp;
1366         init_waitqueue_head(&sdp->o_excl_wait);
1367         sdp->sg_tablesize = scsidp->host ? scsidp->host->sg_tablesize : 0;
1368
1369         sg_nr_dev++;
1370         sg_dev_arr[k] = sdp;
1371         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1372         error = k;
1373
1374  out:
1375         if (error < 0)
1376                 kfree(sdp);
1377         kfree(old_sg_dev_arr);
1378         return error;
1379
1380  expand_failed:
1381         printk(KERN_WARNING "sg_alloc: device array cannot be resized\n");
1382         error = -ENOMEM;
1383         goto out;
1384
1385  overflow:
1386         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1387         printk(KERN_WARNING
1388                "Unable to attach sg device <%d, %d, %d, %d> type=%d, minor "
1389                "number exceeds %d\n", scsidp->host->host_no, scsidp->channel,
1390                scsidp->id, scsidp->lun, scsidp->type, SG_MAX_DEVS - 1);
1391         error = -ENODEV;
1392         goto out;
1393 }
1394
1395 static int
1396 sg_add(struct class_device *cl_dev)
1397 {
1398         struct scsi_device *scsidp = to_scsi_device(cl_dev->dev);
1399         struct gendisk *disk;
1400         Sg_device *sdp = NULL;
1401         struct cdev * cdev = NULL;
1402         int error, k;
1403
1404         disk = alloc_disk(1);
1405         if (!disk) {
1406                 printk(KERN_WARNING "alloc_disk failed\n");
1407                 return -ENOMEM;
1408         }
1409         disk->major = SCSI_GENERIC_MAJOR;
1410
1411         error = -ENOMEM;
1412         cdev = cdev_alloc();
1413         if (!cdev) {
1414                 printk(KERN_WARNING "cdev_alloc failed\n");
1415                 goto out;
1416         }
1417         cdev->owner = THIS_MODULE;
1418         cdev->ops = &sg_fops;
1419
1420         error = sg_alloc(disk, scsidp);
1421         if (error < 0) {
1422                 printk(KERN_WARNING "sg_alloc failed\n");
1423                 goto out;
1424         }
1425         k = error;
1426         sdp = sg_dev_arr[k];
1427
1428         devfs_mk_cdev(MKDEV(SCSI_GENERIC_MAJOR, k),
1429                         S_IFCHR | S_IRUSR | S_IWUSR | S_IRGRP,
1430                         "%s/generic", scsidp->devfs_name);
1431         error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, k), 1);
1432         if (error) {
1433                 devfs_remove("%s/generic", scsidp->devfs_name);
1434                 goto out;
1435         }
1436         sdp->cdev = cdev;
1437         if (sg_sysfs_valid) {
1438                 struct class_device * sg_class_member;
1439
1440                 sg_class_member = class_simple_device_add(sg_sysfs_class,
1441                                 MKDEV(SCSI_GENERIC_MAJOR, k),
1442                                 cl_dev->dev, "%s",
1443                                 disk->disk_name);
1444                 if (IS_ERR(sg_class_member))
1445                         printk(KERN_WARNING "sg_add: "
1446                                 "class_simple_device_add failed\n");
1447                 class_set_devdata(sg_class_member, sdp);
1448                 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1449                                           &sg_class_member->kobj, "generic");
1450                 if (error)
1451                         printk(KERN_ERR "sg_add: unable to make symlink "
1452                                         "'generic' back to sg%d\n", k);
1453         } else
1454                 printk(KERN_WARNING "sg_add: sg_sys INvalid\n");
1455
1456         printk(KERN_NOTICE
1457                "Attached scsi generic sg%d at scsi%d, channel"
1458                " %d, id %d, lun %d,  type %d\n", k,
1459                scsidp->host->host_no, scsidp->channel, scsidp->id,
1460                scsidp->lun, scsidp->type);
1461
1462         return 0;
1463
1464 out:
1465         put_disk(disk);
1466         if (cdev)
1467                 cdev_del(cdev);
1468         return error;
1469 }
1470
1471 static void
1472 sg_remove(struct class_device *cl_dev)
1473 {
1474         struct scsi_device *scsidp = to_scsi_device(cl_dev->dev);
1475         Sg_device *sdp = NULL;
1476         unsigned long iflags;
1477         Sg_fd *sfp;
1478         Sg_fd *tsfp;
1479         Sg_request *srp;
1480         Sg_request *tsrp;
1481         int k, delay;
1482
1483         if (NULL == sg_dev_arr)
1484                 return;
1485         delay = 0;
1486         write_lock_irqsave(&sg_dev_arr_lock, iflags);
1487         for (k = 0; k < sg_dev_max; k++) {
1488                 sdp = sg_dev_arr[k];
1489                 if ((NULL == sdp) || (sdp->device != scsidp))
1490                         continue;       /* dirty but lowers nesting */
1491                 if (sdp->headfp) {
1492                         sdp->detached = 1;
1493                         for (sfp = sdp->headfp; sfp; sfp = tsfp) {
1494                                 tsfp = sfp->nextfp;
1495                                 for (srp = sfp->headrp; srp; srp = tsrp) {
1496                                         tsrp = srp->nextrp;
1497                                         if (sfp->closed || (0 == srp->done))
1498                                                 sg_finish_rem_req(srp);
1499                                 }
1500                                 if (sfp->closed) {
1501                                         scsi_device_put(sdp->device);
1502                                         __sg_remove_sfp(sdp, sfp);
1503                                 } else {
1504                                         delay = 1;
1505                                         wake_up_interruptible(&sfp->read_wait);
1506                                         kill_fasync(&sfp->async_qp, SIGPOLL,
1507                                                     POLL_HUP);
1508                                 }
1509                         }
1510                         SCSI_LOG_TIMEOUT(3, printk("sg_detach: dev=%d, dirty\n", k));
1511                         if (NULL == sdp->headfp) {
1512                                 sg_dev_arr[k] = NULL;
1513                         }
1514                 } else {        /* nothing active, simple case */
1515                         SCSI_LOG_TIMEOUT(3, printk("sg_detach: dev=%d\n", k));
1516                         sg_dev_arr[k] = NULL;
1517                 }
1518                 sg_nr_dev--;
1519                 break;
1520         }
1521         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
1522
1523         if (sdp) {
1524                 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1525                 class_simple_device_remove(MKDEV(SCSI_GENERIC_MAJOR, k));
1526                 cdev_del(sdp->cdev);
1527                 sdp->cdev = NULL;
1528                 devfs_remove("%s/generic", scsidp->devfs_name);
1529                 put_disk(sdp->disk);
1530                 sdp->disk = NULL;
1531                 if (NULL == sdp->headfp)
1532                         kfree((char *) sdp);
1533         }
1534
1535         if (delay)
1536                 msleep(10);     /* dirty detach so delay device destruction */
1537 }
1538
1539 /* Set 'perm' (4th argument) to 0 to disable module_param's definition
1540  * of sysfs parameters (which module_param doesn't yet support).
1541  * Sysfs parameters defined explicitly below.
1542  */
1543 module_param_named(def_reserved_size, def_reserved_size, int, 0);
1544 module_param_named(allow_dio, sg_allow_dio, int, 0);
1545
1546 MODULE_AUTHOR("Douglas Gilbert");
1547 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1548 MODULE_LICENSE("GPL");
1549 MODULE_VERSION(SG_VERSION_STR);
1550
1551 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1552 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1553
1554 static int __init
1555 init_sg(void)
1556 {
1557         int rc;
1558
1559         if (def_reserved_size >= 0)
1560                 sg_big_buff = def_reserved_size;
1561
1562         rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1563                                     SG_MAX_DEVS, "sg");
1564         if (rc)
1565                 return rc;
1566         sg_sysfs_class = class_simple_create(THIS_MODULE, "scsi_generic");
1567         if ( IS_ERR(sg_sysfs_class) ) {
1568                 rc = PTR_ERR(sg_sysfs_class);
1569                 goto err_out;
1570         }
1571         sg_sysfs_valid = 1;
1572         rc = scsi_register_interface(&sg_interface);
1573         if (0 == rc) {
1574 #ifdef CONFIG_SCSI_PROC_FS
1575                 sg_proc_init();
1576 #endif                          /* CONFIG_SCSI_PROC_FS */
1577                 return 0;
1578         }
1579         class_simple_destroy(sg_sysfs_class);
1580 err_out:
1581         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1582         return rc;
1583 }
1584
1585 static void __exit
1586 exit_sg(void)
1587 {
1588 #ifdef CONFIG_SCSI_PROC_FS
1589         sg_proc_cleanup();
1590 #endif                          /* CONFIG_SCSI_PROC_FS */
1591         scsi_unregister_interface(&sg_interface);
1592         class_simple_destroy(sg_sysfs_class);
1593         sg_sysfs_valid = 0;
1594         unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1595                                  SG_MAX_DEVS);
1596         if (sg_dev_arr != NULL) {
1597                 kfree((char *) sg_dev_arr);
1598                 sg_dev_arr = NULL;
1599         }
1600         sg_dev_max = 0;
1601 }
1602
1603 static int
1604 sg_start_req(Sg_request * srp)
1605 {
1606         int res;
1607         Sg_fd *sfp = srp->parentfp;
1608         sg_io_hdr_t *hp = &srp->header;
1609         int dxfer_len = (int) hp->dxfer_len;
1610         int dxfer_dir = hp->dxfer_direction;
1611         Sg_scatter_hold *req_schp = &srp->data;
1612         Sg_scatter_hold *rsv_schp = &sfp->reserve;
1613
1614         SCSI_LOG_TIMEOUT(4, printk("sg_start_req: dxfer_len=%d\n", dxfer_len));
1615         if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1616                 return 0;
1617         if (sg_allow_dio && (hp->flags & SG_FLAG_DIRECT_IO) &&
1618             (dxfer_dir != SG_DXFER_UNKNOWN) && (0 == hp->iovec_count) &&
1619             (!sfp->parentdp->device->host->unchecked_isa_dma)) {
1620                 res = sg_build_direct(srp, sfp, dxfer_len);
1621                 if (res <= 0)   /* -ve -> error, 0 -> done, 1 -> try indirect */
1622                         return res;
1623         }
1624         if ((!sg_res_in_use(sfp)) && (dxfer_len <= rsv_schp->bufflen))
1625                 sg_link_reserve(sfp, srp, dxfer_len);
1626         else {
1627                 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1628                 if (res) {
1629                         sg_remove_scat(req_schp);
1630                         return res;
1631                 }
1632         }
1633         return 0;
1634 }
1635
1636 static void
1637 sg_finish_rem_req(Sg_request * srp)
1638 {
1639         Sg_fd *sfp = srp->parentfp;
1640         Sg_scatter_hold *req_schp = &srp->data;
1641
1642         SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n", (int) srp->res_used));
1643         if (srp->res_used)
1644                 sg_unlink_reserve(sfp, srp);
1645         else
1646                 sg_remove_scat(req_schp);
1647         sg_remove_request(sfp, srp);
1648 }
1649
1650 static int
1651 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1652 {
1653         int ret_sz;
1654         int elem_sz = sizeof (struct scatterlist);
1655         int sg_bufflen = tablesize * elem_sz;
1656         int mx_sc_elems = tablesize;
1657
1658         schp->buffer = sg_page_malloc(sg_bufflen, sfp->low_dma, &ret_sz);
1659         if (!schp->buffer)
1660                 return -ENOMEM;
1661         else if (ret_sz != sg_bufflen) {
1662                 sg_bufflen = ret_sz;
1663                 mx_sc_elems = sg_bufflen / elem_sz;
1664         }
1665         schp->sglist_len = sg_bufflen;
1666         memset(schp->buffer, 0, sg_bufflen);
1667         return mx_sc_elems;     /* number of scat_gath elements allocated */
1668 }
1669
1670 #ifdef SG_ALLOW_DIO_CODE
1671 /* vvvvvvvv  following code borrowed from st driver's direct IO vvvvvvvvv */
1672         /* hopefully this generic code will moved to a library */
1673
1674 /* Pin down user pages and put them into a scatter gather list. Returns <= 0 if
1675    - mapping of all pages not successful
1676    - any page is above max_pfn
1677    (i.e., either completely successful or fails)
1678 */
1679 static int
1680 st_map_user_pages(struct scatterlist *sgl, const unsigned int max_pages,
1681                   unsigned long uaddr, size_t count, int rw,
1682                   unsigned long max_pfn)
1683 {
1684         int res, i, j;
1685         unsigned int nr_pages;
1686         struct page **pages;
1687
1688         nr_pages = ((uaddr & ~PAGE_MASK) + count + ~PAGE_MASK) >> PAGE_SHIFT;
1689
1690         /* User attempted Overflow! */
1691         if ((uaddr + count) < uaddr)
1692                 return -EINVAL;
1693
1694         /* Too big */
1695         if (nr_pages > max_pages)
1696                 return -ENOMEM;
1697
1698         /* Hmm? */
1699         if (count == 0)
1700                 return 0;
1701
1702         if ((pages = kmalloc(max_pages * sizeof(*pages), GFP_ATOMIC)) == NULL)
1703                 return -ENOMEM;
1704
1705         /* Try to fault in all of the necessary pages */
1706         down_read(&current->mm->mmap_sem);
1707         /* rw==READ means read from drive, write into memory area */
1708         res = get_user_pages(
1709                 current,
1710                 current->mm,
1711                 uaddr,
1712                 nr_pages,
1713                 rw == READ,
1714                 0, /* don't force */
1715                 pages,
1716                 NULL);
1717         up_read(&current->mm->mmap_sem);
1718
1719         /* Errors and no page mapped should return here */
1720         if (res < nr_pages)
1721                 goto out_unmap;
1722
1723         for (i=0; i < nr_pages; i++) {
1724                 /* FIXME: flush superflous for rw==READ,
1725                  * probably wrong function for rw==WRITE
1726                  */
1727                 flush_dcache_page(pages[i]);
1728                 if (page_to_pfn(pages[i]) > max_pfn)
1729                         goto out_unlock;
1730                 /* ?? Is locking needed? I don't think so */
1731                 /* if (TestSetPageLocked(pages[i]))
1732                    goto out_unlock; */
1733         }
1734
1735         /* Populate the scatter/gather list */
1736         sgl[0].page = pages[0];
1737         sgl[0].offset = uaddr & ~PAGE_MASK;
1738         if (nr_pages > 1) {
1739                 sgl[0].length = PAGE_SIZE - sgl[0].offset;
1740                 count -= sgl[0].length;
1741                 for (i=1; i < nr_pages ; i++) {
1742                         sgl[i].offset = 0;
1743                         sgl[i].page = pages[i];
1744                         sgl[i].length = count < PAGE_SIZE ? count : PAGE_SIZE;
1745                         count -= PAGE_SIZE;
1746                 }
1747         }
1748         else {
1749                 sgl[0].length = count;
1750         }
1751
1752         kfree(pages);
1753         return nr_pages;
1754
1755  out_unlock:
1756         /* for (j=0; j < i; j++)
1757            unlock_page(pages[j]); */
1758         res = 0;
1759  out_unmap:
1760         if (res > 0)
1761                 for (j=0; j < res; j++)
1762                         page_cache_release(pages[j]);
1763         kfree(pages);
1764         return res;
1765 }
1766
1767
1768 /* And unmap them... */
1769 static int
1770 st_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_pages,
1771                     int dirtied)
1772 {
1773         int i;
1774
1775         for (i=0; i < nr_pages; i++) {
1776                 if (dirtied && !PageReserved(sgl[i].page))
1777                         SetPageDirty(sgl[i].page);
1778                 /* unlock_page(sgl[i].page); */
1779                 /* FIXME: cache flush missing for rw==READ
1780                  * FIXME: call the correct reference counting function
1781                  */
1782                 page_cache_release(sgl[i].page);
1783         }
1784
1785         return 0;
1786 }
1787
1788 /* ^^^^^^^^  above code borrowed from st driver's direct IO ^^^^^^^^^ */
1789 #endif
1790
1791
1792 /* Returns: -ve -> error, 0 -> done, 1 -> try indirect */
1793 static int
1794 sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len)
1795 {
1796 #ifdef SG_ALLOW_DIO_CODE
1797         sg_io_hdr_t *hp = &srp->header;
1798         Sg_scatter_hold *schp = &srp->data;
1799         int sg_tablesize = sfp->parentdp->sg_tablesize;
1800         struct scatterlist *sgl;
1801         int mx_sc_elems, res;
1802         struct scsi_device *sdev = sfp->parentdp->device;
1803
1804         if (((unsigned long)hp->dxferp &
1805                         queue_dma_alignment(sdev->request_queue)) != 0)
1806                 return 1;
1807         mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1808         if (mx_sc_elems <= 0) {
1809                 return 1;
1810         }
1811         sgl = (struct scatterlist *)schp->buffer;
1812         res = st_map_user_pages(sgl, mx_sc_elems, (unsigned long)hp->dxferp, dxfer_len,
1813                                 (SG_DXFER_TO_DEV == hp->dxfer_direction) ? 1 : 0, ULONG_MAX);
1814         if (res <= 0)
1815                 return 1;
1816         schp->k_use_sg = res;
1817         schp->dio_in_use = 1;
1818         hp->info |= SG_INFO_DIRECT_IO;
1819         return 0;
1820 #else
1821         return 1;
1822 #endif
1823 }
1824
1825 static int
1826 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1827 {
1828         int ret_sz;
1829         int blk_size = buff_size;
1830         unsigned char *p = NULL;
1831
1832         if ((blk_size < 0) || (!sfp))
1833                 return -EFAULT;
1834         if (0 == blk_size)
1835                 ++blk_size;     /* don't know why */
1836 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1837         blk_size = (blk_size + SG_SECTOR_MSK) & (~SG_SECTOR_MSK);
1838         SCSI_LOG_TIMEOUT(4, printk("sg_build_indirect: buff_size=%d, blk_size=%d\n",
1839                                    buff_size, blk_size));
1840         if (blk_size <= SG_SCATTER_SZ) {
1841                 p = sg_page_malloc(blk_size, sfp->low_dma, &ret_sz);
1842                 if (!p)
1843                         return -ENOMEM;
1844                 if (blk_size == ret_sz) {       /* got it on the first attempt */
1845                         schp->k_use_sg = 0;
1846                         schp->buffer = p;
1847                         schp->bufflen = blk_size;
1848                         schp->b_malloc_len = blk_size;
1849                         return 0;
1850                 }
1851         } else {
1852                 p = sg_page_malloc(SG_SCATTER_SZ, sfp->low_dma, &ret_sz);
1853                 if (!p)
1854                         return -ENOMEM;
1855         }
1856 /* Want some local declarations, so start new block ... */
1857         {                       /* lets try and build a scatter gather list */
1858                 struct scatterlist *sclp;
1859                 int k, rem_sz, num;
1860                 int mx_sc_elems;
1861                 int sg_tablesize = sfp->parentdp->sg_tablesize;
1862                 int first = 1;
1863
1864                 /* N.B. ret_sz carried into this block ... */
1865                 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1866                 if (mx_sc_elems < 0)
1867                         return mx_sc_elems;     /* most likely -ENOMEM */
1868
1869                 for (k = 0, sclp = schp->buffer, rem_sz = blk_size;
1870                      (rem_sz > 0) && (k < mx_sc_elems);
1871                      ++k, rem_sz -= ret_sz, ++sclp) {
1872                         if (first)
1873                                 first = 0;
1874                         else {
1875                                 num =
1876                                     (rem_sz >
1877                                      SG_SCATTER_SZ) ? SG_SCATTER_SZ : rem_sz;
1878                                 p = sg_page_malloc(num, sfp->low_dma, &ret_sz);
1879                                 if (!p)
1880                                         break;
1881                         }
1882                         sclp->page = virt_to_page(p);
1883                         sclp->offset = offset_in_page(p);
1884                         sclp->length = ret_sz;
1885
1886                         SCSI_LOG_TIMEOUT(5, printk("sg_build_build: k=%d, a=0x%p, len=%d\n",
1887                                           k, sg_scatg2virt(sclp), ret_sz));
1888                 }               /* end of for loop */
1889                 schp->k_use_sg = k;
1890                 SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, rem_sz=%d\n", k, rem_sz));
1891                 schp->bufflen = blk_size;
1892                 if (rem_sz > 0) /* must have failed */
1893                         return -ENOMEM;
1894         }
1895         return 0;
1896 }
1897
1898 static int
1899 sg_write_xfer(Sg_request * srp)
1900 {
1901         sg_io_hdr_t *hp = &srp->header;
1902         Sg_scatter_hold *schp = &srp->data;
1903         int num_xfer = 0;
1904         int j, k, onum, usglen, ksglen, res;
1905         int iovec_count = (int) hp->iovec_count;
1906         int dxfer_dir = hp->dxfer_direction;
1907         unsigned char *p;
1908         unsigned char __user *up;
1909         int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
1910
1911         if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_TO_DEV == dxfer_dir) ||
1912             (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
1913                 num_xfer = (int) (new_interface ? hp->dxfer_len : hp->flags);
1914                 if (schp->bufflen < num_xfer)
1915                         num_xfer = schp->bufflen;
1916         }
1917         if ((num_xfer <= 0) || (schp->dio_in_use) ||
1918             (new_interface
1919              && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
1920                 return 0;
1921
1922         SCSI_LOG_TIMEOUT(4, printk("sg_write_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
1923                           num_xfer, iovec_count, schp->k_use_sg));
1924         if (iovec_count) {
1925                 onum = iovec_count;
1926                 if ((k = verify_area(VERIFY_READ, hp->dxferp,
1927                                      SZ_SG_IOVEC * onum)))
1928                         return k;
1929         } else
1930                 onum = 1;
1931
1932         if (0 == schp->k_use_sg) {      /* kernel has single buffer */
1933                 for (j = 0, p = schp->buffer; j < onum; ++j) {
1934                         res = sg_u_iovec(hp, iovec_count, j, 1, &usglen, &up);
1935                         if (res)
1936                                 return res;
1937                         usglen = (num_xfer > usglen) ? usglen : num_xfer;
1938                         if (__copy_from_user(p, up, usglen))
1939                                 return -EFAULT;
1940                         p += usglen;
1941                         num_xfer -= usglen;
1942                         if (num_xfer <= 0)
1943                                 return 0;
1944                 }
1945         } else {                /* kernel using scatter gather list */
1946                 struct scatterlist *sclp = (struct scatterlist *) schp->buffer;
1947
1948                 ksglen = (int) sclp->length;
1949                 p = sg_scatg2virt(sclp);
1950                 for (j = 0, k = 0; j < onum; ++j) {
1951                         res = sg_u_iovec(hp, iovec_count, j, 1, &usglen, &up);
1952                         if (res)
1953                                 return res;
1954
1955                         for (; p; ++sclp, ksglen = (int) sclp->length,
1956                                   p = sg_scatg2virt(sclp)) {
1957                                 if (usglen <= 0)
1958                                         break;
1959                                 if (ksglen > usglen) {
1960                                         if (usglen >= num_xfer) {
1961                                                 if (__copy_from_user
1962                                                     (p, up, num_xfer))
1963                                                         return -EFAULT;
1964                                                 return 0;
1965                                         }
1966                                         if (__copy_from_user(p, up, usglen))
1967                                                 return -EFAULT;
1968                                         p += usglen;
1969                                         ksglen -= usglen;
1970                                         break;
1971                                 } else {
1972                                         if (ksglen >= num_xfer) {
1973                                                 if (__copy_from_user
1974                                                     (p, up, num_xfer))
1975                                                         return -EFAULT;
1976                                                 return 0;
1977                                         }
1978                                         if (__copy_from_user(p, up, ksglen))
1979                                                 return -EFAULT;
1980                                         up += ksglen;
1981                                         usglen -= ksglen;
1982                                 }
1983                                 ++k;
1984                                 if (k >= schp->k_use_sg)
1985                                         return 0;
1986                         }
1987                 }
1988         }
1989         return 0;
1990 }
1991
1992 static int
1993 sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
1994            int wr_xf, int *countp, unsigned char __user **up)
1995 {
1996         int num_xfer = (int) hp->dxfer_len;
1997         unsigned char __user *p = hp->dxferp;
1998         int count, k;
1999
2000         if (0 == sg_num) {
2001                 if (wr_xf && ('\0' == hp->interface_id))
2002                         count = (int) hp->flags;        /* holds "old" input_size */
2003                 else
2004                         count = num_xfer;
2005         } else {
2006                 sg_iovec_t iovec;
2007                 if (__copy_from_user(&iovec, p + ind*SZ_SG_IOVEC, SZ_SG_IOVEC))
2008                         return -EFAULT;
2009                 p = iovec.iov_base;
2010                 count = (int) iovec.iov_len;
2011         }
2012         if ((k = verify_area(wr_xf ? VERIFY_READ : VERIFY_WRITE, p, count)))
2013                 return k;
2014         if (up)
2015                 *up = p;
2016         if (countp)
2017                 *countp = count;
2018         return 0;
2019 }
2020
2021 static void
2022 sg_remove_scat(Sg_scatter_hold * schp)
2023 {
2024         SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
2025         if (schp->buffer && (schp->sglist_len > 0)) {
2026                 struct scatterlist *sclp = (struct scatterlist *) schp->buffer;
2027
2028                 if (schp->dio_in_use) {
2029 #ifdef SG_ALLOW_DIO_CODE
2030                         st_unmap_user_pages(sclp, schp->k_use_sg, TRUE);
2031 #endif
2032                 } else {
2033                         int k;
2034
2035                         for (k = 0; (k < schp->k_use_sg) && sg_scatg2virt(sclp);
2036                              ++k, ++sclp) {
2037                                 SCSI_LOG_TIMEOUT(5, printk(
2038                                     "sg_remove_scat: k=%d, a=0x%p, len=%d\n",
2039                                     k, sg_scatg2virt(sclp), sclp->length));
2040                                 sg_page_free(sg_scatg2virt(sclp), sclp->length);
2041                                 sclp->page = NULL;
2042                                 sclp->offset = 0;
2043                                 sclp->length = 0;
2044                         }
2045                 }
2046                 sg_page_free(schp->buffer, schp->sglist_len);
2047         } else if (schp->buffer)
2048                 sg_page_free(schp->buffer, schp->b_malloc_len);
2049         memset(schp, 0, sizeof (*schp));
2050 }
2051
2052 static int
2053 sg_read_xfer(Sg_request * srp)
2054 {
2055         sg_io_hdr_t *hp = &srp->header;
2056         Sg_scatter_hold *schp = &srp->data;
2057         int num_xfer = 0;
2058         int j, k, onum, usglen, ksglen, res;
2059         int iovec_count = (int) hp->iovec_count;
2060         int dxfer_dir = hp->dxfer_direction;
2061         unsigned char *p;
2062         unsigned char __user *up;
2063         int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
2064
2065         if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_FROM_DEV == dxfer_dir)
2066             || (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
2067                 num_xfer = hp->dxfer_len;
2068                 if (schp->bufflen < num_xfer)
2069                         num_xfer = schp->bufflen;
2070         }
2071         if ((num_xfer <= 0) || (schp->dio_in_use) ||
2072             (new_interface
2073              && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
2074                 return 0;
2075
2076         SCSI_LOG_TIMEOUT(4, printk("sg_read_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
2077                           num_xfer, iovec_count, schp->k_use_sg));
2078         if (iovec_count) {
2079                 onum = iovec_count;
2080                 if ((k = verify_area(VERIFY_READ, hp->dxferp,
2081                                      SZ_SG_IOVEC * onum)))
2082                         return k;
2083         } else
2084                 onum = 1;
2085
2086         if (0 == schp->k_use_sg) {      /* kernel has single buffer */
2087                 for (j = 0, p = schp->buffer; j < onum; ++j) {
2088                         res = sg_u_iovec(hp, iovec_count, j, 0, &usglen, &up);
2089                         if (res)
2090                                 return res;
2091                         usglen = (num_xfer > usglen) ? usglen : num_xfer;
2092                         if (__copy_to_user(up, p, usglen))
2093                                 return -EFAULT;
2094                         p += usglen;
2095                         num_xfer -= usglen;
2096                         if (num_xfer <= 0)
2097                                 return 0;
2098                 }
2099         } else {                /* kernel using scatter gather list */
2100                 struct scatterlist *sclp = (struct scatterlist *) schp->buffer;
2101
2102                 ksglen = (int) sclp->length;
2103                 p = sg_scatg2virt(sclp);
2104                 for (j = 0, k = 0; j < onum; ++j) {
2105                         res = sg_u_iovec(hp, iovec_count, j, 0, &usglen, &up);
2106                         if (res)
2107                                 return res;
2108
2109                         for (; p; ++sclp, ksglen = (int) sclp->length,
2110                                   p = sg_scatg2virt(sclp)) {
2111                                 if (usglen <= 0)
2112                                         break;
2113                                 if (ksglen > usglen) {
2114                                         if (usglen >= num_xfer) {
2115                                                 if (__copy_to_user
2116                                                     (up, p, num_xfer))
2117                                                         return -EFAULT;
2118                                                 return 0;
2119                                         }
2120                                         if (__copy_to_user(up, p, usglen))
2121                                                 return -EFAULT;
2122                                         p += usglen;
2123                                         ksglen -= usglen;
2124                                         break;
2125                                 } else {
2126                                         if (ksglen >= num_xfer) {
2127                                                 if (__copy_to_user
2128                                                     (up, p, num_xfer))
2129                                                         return -EFAULT;
2130                                                 return 0;
2131                                         }
2132                                         if (__copy_to_user(up, p, ksglen))
2133                                                 return -EFAULT;
2134                                         up += ksglen;
2135                                         usglen -= ksglen;
2136                                 }
2137                                 ++k;
2138                                 if (k >= schp->k_use_sg)
2139                                         return 0;
2140                         }
2141                 }
2142         }
2143         return 0;
2144 }
2145
2146 static int
2147 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
2148 {
2149         Sg_scatter_hold *schp = &srp->data;
2150
2151         SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n",
2152                                    num_read_xfer));
2153         if ((!outp) || (num_read_xfer <= 0))
2154                 return 0;
2155         if (schp->k_use_sg > 0) {
2156                 int k, num;
2157                 struct scatterlist *sclp = (struct scatterlist *) schp->buffer;
2158
2159                 for (k = 0; (k < schp->k_use_sg) && sg_scatg2virt(sclp);
2160                      ++k, ++sclp) {
2161                         num = (int) sclp->length;
2162                         if (num > num_read_xfer) {
2163                                 if (__copy_to_user
2164                                     (outp, sg_scatg2virt(sclp), num_read_xfer))
2165                                         return -EFAULT;
2166                                 break;
2167                         } else {
2168                                 if (__copy_to_user
2169                                     (outp, sg_scatg2virt(sclp), num))
2170                                         return -EFAULT;
2171                                 num_read_xfer -= num;
2172                                 if (num_read_xfer <= 0)
2173                                         break;
2174                                 outp += num;
2175                         }
2176                 }
2177         } else {
2178                 if (__copy_to_user(outp, schp->buffer, num_read_xfer))
2179                         return -EFAULT;
2180         }
2181         return 0;
2182 }
2183
2184 static void
2185 sg_build_reserve(Sg_fd * sfp, int req_size)
2186 {
2187         Sg_scatter_hold *schp = &sfp->reserve;
2188
2189         SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
2190         do {
2191                 if (req_size < PAGE_SIZE)
2192                         req_size = PAGE_SIZE;
2193                 if (0 == sg_build_indirect(schp, sfp, req_size))
2194                         return;
2195                 else
2196                         sg_remove_scat(schp);
2197                 req_size >>= 1; /* divide by 2 */
2198         } while (req_size > (PAGE_SIZE / 2));
2199 }
2200
2201 static void
2202 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2203 {
2204         Sg_scatter_hold *req_schp = &srp->data;
2205         Sg_scatter_hold *rsv_schp = &sfp->reserve;
2206
2207         srp->res_used = 1;
2208         SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
2209         size = (size + 1) & (~1);       /* round to even for aha1542 */
2210         if (rsv_schp->k_use_sg > 0) {
2211                 int k, num;
2212                 int rem = size;
2213                 struct scatterlist *sclp =
2214                     (struct scatterlist *) rsv_schp->buffer;
2215
2216                 for (k = 0; k < rsv_schp->k_use_sg; ++k, ++sclp) {
2217                         num = (int) sclp->length;
2218                         if (rem <= num) {
2219                                 if (0 == k) {
2220                                         req_schp->k_use_sg = 0;
2221                                         req_schp->buffer = sg_scatg2virt(sclp);
2222                                 } else {
2223                                         sfp->save_scat_len = num;
2224                                         sclp->length = (unsigned) rem;
2225                                         req_schp->k_use_sg = k + 1;
2226                                         req_schp->sglist_len =
2227                                             rsv_schp->sglist_len;
2228                                         req_schp->buffer = rsv_schp->buffer;
2229                                 }
2230                                 req_schp->bufflen = size;
2231                                 req_schp->b_malloc_len = rsv_schp->b_malloc_len;
2232                                 break;
2233                         } else
2234                                 rem -= num;
2235                 }
2236                 if (k >= rsv_schp->k_use_sg)
2237                         SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
2238         } else {
2239                 req_schp->k_use_sg = 0;
2240                 req_schp->bufflen = size;
2241                 req_schp->buffer = rsv_schp->buffer;
2242                 req_schp->b_malloc_len = rsv_schp->b_malloc_len;
2243         }
2244 }
2245
2246 static void
2247 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2248 {
2249         Sg_scatter_hold *req_schp = &srp->data;
2250         Sg_scatter_hold *rsv_schp = &sfp->reserve;
2251
2252         SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->k_use_sg=%d\n",
2253                                    (int) req_schp->k_use_sg));
2254         if ((rsv_schp->k_use_sg > 0) && (req_schp->k_use_sg > 0)) {
2255                 struct scatterlist *sclp =
2256                     (struct scatterlist *) rsv_schp->buffer;
2257
2258                 if (sfp->save_scat_len > 0)
2259                         (sclp + (req_schp->k_use_sg - 1))->length =
2260                             (unsigned) sfp->save_scat_len;
2261                 else
2262                         SCSI_LOG_TIMEOUT(1, printk ("sg_unlink_reserve: BAD save_scat_len\n"));
2263         }
2264         req_schp->k_use_sg = 0;
2265         req_schp->bufflen = 0;
2266         req_schp->buffer = NULL;
2267         req_schp->sglist_len = 0;
2268         sfp->save_scat_len = 0;
2269         srp->res_used = 0;
2270 }
2271
2272 static Sg_request *
2273 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2274 {
2275         Sg_request *resp;
2276         unsigned long iflags;
2277
2278         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2279         for (resp = sfp->headrp; resp; resp = resp->nextrp) {
2280                 /* look for requests that are ready + not SG_IO owned */
2281                 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2282                     ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2283                         resp->done = 2; /* guard against other readers */
2284                         break;
2285                 }
2286         }
2287         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2288         return resp;
2289 }
2290
2291 #ifdef CONFIG_SCSI_PROC_FS
2292 static Sg_request *
2293 sg_get_nth_request(Sg_fd * sfp, int nth)
2294 {
2295         Sg_request *resp;
2296         unsigned long iflags;
2297         int k;
2298
2299         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2300         for (k = 0, resp = sfp->headrp; resp && (k < nth);
2301              ++k, resp = resp->nextrp) ;
2302         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2303         return resp;
2304 }
2305 #endif
2306
2307 /* always adds to end of list */
2308 static Sg_request *
2309 sg_add_request(Sg_fd * sfp)
2310 {
2311         int k;
2312         unsigned long iflags;
2313         Sg_request *resp;
2314         Sg_request *rp = sfp->req_arr;
2315
2316         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2317         resp = sfp->headrp;
2318         if (!resp) {
2319                 memset(rp, 0, sizeof (Sg_request));
2320                 rp->parentfp = sfp;
2321                 resp = rp;
2322                 sfp->headrp = resp;
2323         } else {
2324                 if (0 == sfp->cmd_q)
2325                         resp = NULL;    /* command queuing disallowed */
2326                 else {
2327                         for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2328                                 if (!rp->parentfp)
2329                                         break;
2330                         }
2331                         if (k < SG_MAX_QUEUE) {
2332                                 memset(rp, 0, sizeof (Sg_request));
2333                                 rp->parentfp = sfp;
2334                                 while (resp->nextrp)
2335                                         resp = resp->nextrp;
2336                                 resp->nextrp = rp;
2337                                 resp = rp;
2338                         } else
2339                                 resp = NULL;
2340                 }
2341         }
2342         if (resp) {
2343                 resp->nextrp = NULL;
2344                 resp->header.duration = jiffies;
2345                 resp->my_cmdp = NULL;
2346         }
2347         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2348         return resp;
2349 }
2350
2351 /* Return of 1 for found; 0 for not found */
2352 static int
2353 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2354 {
2355         Sg_request *prev_rp;
2356         Sg_request *rp;
2357         unsigned long iflags;
2358         int res = 0;
2359
2360         if ((!sfp) || (!srp) || (!sfp->headrp))
2361                 return res;
2362         write_lock_irqsave(&sfp->rq_list_lock, iflags);
2363         prev_rp = sfp->headrp;
2364         if (srp == prev_rp) {
2365                 sfp->headrp = prev_rp->nextrp;
2366                 prev_rp->parentfp = NULL;
2367                 res = 1;
2368         } else {
2369                 while ((rp = prev_rp->nextrp)) {
2370                         if (srp == rp) {
2371                                 prev_rp->nextrp = rp->nextrp;
2372                                 rp->parentfp = NULL;
2373                                 res = 1;
2374                                 break;
2375                         }
2376                         prev_rp = rp;
2377                 }
2378         }
2379         write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2380         return res;
2381 }
2382
2383 #ifdef CONFIG_SCSI_PROC_FS
2384 static Sg_fd *
2385 sg_get_nth_sfp(Sg_device * sdp, int nth)
2386 {
2387         Sg_fd *resp;
2388         unsigned long iflags;
2389         int k;
2390
2391         read_lock_irqsave(&sg_dev_arr_lock, iflags);
2392         for (k = 0, resp = sdp->headfp; resp && (k < nth);
2393              ++k, resp = resp->nextfp) ;
2394         read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2395         return resp;
2396 }
2397 #endif
2398
2399 static Sg_fd *
2400 sg_add_sfp(Sg_device * sdp, int dev)
2401 {
2402         Sg_fd *sfp;
2403         unsigned long iflags;
2404
2405         sfp = (Sg_fd *) sg_page_malloc(sizeof (Sg_fd), 0, NULL);
2406         if (!sfp)
2407                 return NULL;
2408         memset(sfp, 0, sizeof (Sg_fd));
2409         init_waitqueue_head(&sfp->read_wait);
2410         sfp->rq_list_lock = RW_LOCK_UNLOCKED;
2411
2412         sfp->timeout = SG_DEFAULT_TIMEOUT;
2413         sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2414         sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2415         sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
2416             sdp->device->host->unchecked_isa_dma : 1;
2417         sfp->cmd_q = SG_DEF_COMMAND_Q;
2418         sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2419         sfp->parentdp = sdp;
2420         write_lock_irqsave(&sg_dev_arr_lock, iflags);
2421         if (!sdp->headfp)
2422                 sdp->headfp = sfp;
2423         else {                  /* add to tail of existing list */
2424                 Sg_fd *pfp = sdp->headfp;
2425                 while (pfp->nextfp)
2426                         pfp = pfp->nextfp;
2427                 pfp->nextfp = sfp;
2428         }
2429         write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2430         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));
2431         sg_build_reserve(sfp, sg_big_buff);
2432         SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp:   bufflen=%d, k_use_sg=%d\n",
2433                            sfp->reserve.bufflen, sfp->reserve.k_use_sg));
2434         return sfp;
2435 }
2436
2437 static void
2438 __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2439 {
2440         Sg_fd *fp;
2441         Sg_fd *prev_fp;
2442
2443         prev_fp = sdp->headfp;
2444         if (sfp == prev_fp)
2445                 sdp->headfp = prev_fp->nextfp;
2446         else {
2447                 while ((fp = prev_fp->nextfp)) {
2448                         if (sfp == fp) {
2449                                 prev_fp->nextfp = fp->nextfp;
2450                                 break;
2451                         }
2452                         prev_fp = fp;
2453                 }
2454         }
2455         if (sfp->reserve.bufflen > 0) {
2456                 SCSI_LOG_TIMEOUT(6,
2457                         printk("__sg_remove_sfp:    bufflen=%d, k_use_sg=%d\n",
2458                         (int) sfp->reserve.bufflen, (int) sfp->reserve.k_use_sg));
2459                 if (sfp->mmap_called)
2460                         sg_rb_correct4mmap(&sfp->reserve, 0);   /* undo correction */
2461                 sg_remove_scat(&sfp->reserve);
2462         }
2463         sfp->parentdp = NULL;
2464         SCSI_LOG_TIMEOUT(6, printk("__sg_remove_sfp:    sfp=0x%p\n", sfp));
2465         sg_page_free((char *) sfp, sizeof (Sg_fd));
2466 }
2467
2468 /* Returns 0 in normal case, 1 when detached and sdp object removed */
2469 static int
2470 sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2471 {
2472         Sg_request *srp;
2473         Sg_request *tsrp;
2474         int dirty = 0;
2475         int res = 0;
2476
2477         for (srp = sfp->headrp; srp; srp = tsrp) {
2478                 tsrp = srp->nextrp;
2479                 if (srp->done)
2480                         sg_finish_rem_req(srp);
2481                 else
2482                         ++dirty;
2483         }
2484         if (0 == dirty) {
2485                 unsigned long iflags;
2486
2487                 write_lock_irqsave(&sg_dev_arr_lock, iflags);
2488                 __sg_remove_sfp(sdp, sfp);
2489                 if (sdp->detached && (NULL == sdp->headfp)) {
2490                         int k, maxd;
2491
2492                         maxd = sg_dev_max;
2493                         for (k = 0; k < maxd; ++k) {
2494                                 if (sdp == sg_dev_arr[k])
2495                                         break;
2496                         }
2497                         if (k < maxd)
2498                                 sg_dev_arr[k] = NULL;
2499                         kfree((char *) sdp);
2500                         res = 1;
2501                 }
2502                 write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2503         } else {
2504                 /* MOD_INC's to inhibit unloading sg and associated adapter driver */
2505                 /* only bump the access_count if we actually succeeded in
2506                  * throwing another counter on the host module */
2507                 scsi_device_get(sdp->device);   /* XXX: retval ignored? */
2508                 sfp->closed = 1;        /* flag dirty state on this fd */
2509                 SCSI_LOG_TIMEOUT(1, printk("sg_remove_sfp: worrisome, %d writes pending\n",
2510                                   dirty));
2511         }
2512         return res;
2513 }
2514
2515 static int
2516 sg_res_in_use(Sg_fd * sfp)
2517 {
2518         const Sg_request *srp;
2519         unsigned long iflags;
2520
2521         read_lock_irqsave(&sfp->rq_list_lock, iflags);
2522         for (srp = sfp->headrp; srp; srp = srp->nextrp)
2523                 if (srp->res_used)
2524                         break;
2525         read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2526         return srp ? 1 : 0;
2527 }
2528
2529 /* If retSzp==NULL want exact size or fail */
2530 static char *
2531 sg_page_malloc(int rqSz, int lowDma, int *retSzp)
2532 {
2533         char *resp = NULL;
2534         int page_mask;
2535         int order, a_size;
2536         int resSz = rqSz;
2537
2538         if (rqSz <= 0)
2539                 return resp;
2540
2541         if (lowDma)
2542                 page_mask = GFP_ATOMIC | GFP_DMA | __GFP_NOWARN;
2543         else
2544                 page_mask = GFP_ATOMIC | __GFP_NOWARN;
2545
2546         for (order = 0, a_size = PAGE_SIZE; a_size < rqSz;
2547              order++, a_size <<= 1) ;
2548         resp = (char *) __get_free_pages(page_mask, order);
2549         while ((!resp) && order && retSzp) {
2550                 --order;
2551                 a_size >>= 1;   /* divide by 2, until PAGE_SIZE */
2552                 resp = (char *) __get_free_pages(page_mask, order);     /* try half */
2553                 resSz = a_size;
2554         }
2555         if (resp) {
2556                 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2557                         memset(resp, 0, resSz);
2558                 if (retSzp)
2559                         *retSzp = resSz;
2560         }
2561         return resp;
2562 }
2563
2564 static void
2565 sg_page_free(char *buff, int size)
2566 {
2567         int order, a_size;
2568
2569         if (!buff)
2570                 return;
2571         for (order = 0, a_size = PAGE_SIZE; a_size < size;
2572              order++, a_size <<= 1) ;
2573         free_pages((unsigned long) buff, order);
2574 }
2575
2576 static unsigned char allow_ops[] = { TEST_UNIT_READY, REQUEST_SENSE,
2577         INQUIRY, READ_CAPACITY, READ_BUFFER, READ_6, READ_10, READ_12,
2578         MODE_SENSE, MODE_SENSE_10, LOG_SENSE
2579 };
2580
2581 static int
2582 sg_allow_access(unsigned char opcode, char dev_type)
2583 {
2584         int k;
2585
2586         if (TYPE_SCANNER == dev_type)   /* TYPE_ROM maybe burner */
2587                 return 1;
2588         for (k = 0; k < sizeof (allow_ops); ++k) {
2589                 if (opcode == allow_ops[k])
2590                         return 1;
2591         }
2592         return 0;
2593 }
2594
2595 #ifdef CONFIG_SCSI_PROC_FS
2596 static int
2597 sg_last_dev(void)
2598 {
2599         int k;
2600         unsigned long iflags;
2601
2602         read_lock_irqsave(&sg_dev_arr_lock, iflags);
2603         for (k = sg_dev_max - 1; k >= 0; --k)
2604                 if (sg_dev_arr[k] && sg_dev_arr[k]->device)
2605                         break;
2606         read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2607         return k + 1;           /* origin 1 */
2608 }
2609 #endif
2610
2611 static Sg_device *
2612 sg_get_dev(int dev)
2613 {
2614         Sg_device *sdp = NULL;
2615         unsigned long iflags;
2616
2617         if (sg_dev_arr && (dev >= 0)) {
2618                 read_lock_irqsave(&sg_dev_arr_lock, iflags);
2619                 if (dev < sg_dev_max)
2620                         sdp = sg_dev_arr[dev];
2621                 read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
2622         }
2623         return sdp;
2624 }
2625
2626 #ifdef CONFIG_SCSI_PROC_FS
2627
2628 static struct proc_dir_entry *sg_proc_sgp = NULL;
2629
2630 static char sg_proc_sg_dirname[] = "scsi/sg";
2631
2632 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2633
2634 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2635 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2636                                   size_t count, loff_t *off);
2637 static struct file_operations adio_fops = {
2638         /* .owner, .read and .llseek added in sg_proc_init() */
2639         .open = sg_proc_single_open_adio,
2640         .write = sg_proc_write_adio,
2641         .release = single_release,
2642 };
2643
2644 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2645 static ssize_t sg_proc_write_dressz(struct file *filp,
2646                 const char __user *buffer, size_t count, loff_t *off);
2647 static struct file_operations dressz_fops = {
2648         .open = sg_proc_single_open_dressz,
2649         .write = sg_proc_write_dressz,
2650         .release = single_release,
2651 };
2652
2653 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2654 static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2655 static struct file_operations version_fops = {
2656         .open = sg_proc_single_open_version,
2657         .release = single_release,
2658 };
2659
2660 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2661 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2662 static struct file_operations devhdr_fops = {
2663         .open = sg_proc_single_open_devhdr,
2664         .release = single_release,
2665 };
2666
2667 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2668 static int sg_proc_open_dev(struct inode *inode, struct file *file);
2669 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2670 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2671 static void dev_seq_stop(struct seq_file *s, void *v);
2672 static struct file_operations dev_fops = {
2673         .open = sg_proc_open_dev,
2674         .release = seq_release,
2675 };
2676 static struct seq_operations dev_seq_ops = {
2677         .start = dev_seq_start,
2678         .next  = dev_seq_next,
2679         .stop  = dev_seq_stop,
2680         .show  = sg_proc_seq_show_dev,
2681 };
2682
2683 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2684 static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2685 static struct file_operations devstrs_fops = {
2686         .open = sg_proc_open_devstrs,
2687         .release = seq_release,
2688 };
2689 static struct seq_operations devstrs_seq_ops = {
2690         .start = dev_seq_start,
2691         .next  = dev_seq_next,
2692         .stop  = dev_seq_stop,
2693         .show  = sg_proc_seq_show_devstrs,
2694 };
2695
2696 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2697 static int sg_proc_open_debug(struct inode *inode, struct file *file);
2698 static struct file_operations debug_fops = {
2699         .open = sg_proc_open_debug,
2700         .release = seq_release,
2701 };
2702 static struct seq_operations debug_seq_ops = {
2703         .start = dev_seq_start,
2704         .next  = dev_seq_next,
2705         .stop  = dev_seq_stop,
2706         .show  = sg_proc_seq_show_debug,
2707 };
2708
2709
2710 struct sg_proc_leaf {
2711         const char * name;
2712         struct file_operations * fops;
2713 };
2714
2715 static struct sg_proc_leaf sg_proc_leaf_arr[] = {
2716         {"allow_dio", &adio_fops},
2717         {"debug", &debug_fops},
2718         {"def_reserved_size", &dressz_fops},
2719         {"device_hdr", &devhdr_fops},
2720         {"devices", &dev_fops},
2721         {"device_strs", &devstrs_fops},
2722         {"version", &version_fops}
2723 };
2724
2725 static int
2726 sg_proc_init(void)
2727 {
2728         int k, mask;
2729         int num_leaves =
2730             sizeof (sg_proc_leaf_arr) / sizeof (sg_proc_leaf_arr[0]);
2731         struct proc_dir_entry *pdep;
2732         struct sg_proc_leaf * leaf;
2733
2734         sg_proc_sgp = create_proc_entry(sg_proc_sg_dirname,
2735                                         S_IFDIR | S_IRUGO | S_IXUGO, NULL);
2736         if (!sg_proc_sgp)
2737                 return 1;
2738         for (k = 0; k < num_leaves; ++k) {
2739                 leaf = &sg_proc_leaf_arr[k];
2740                 mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2741                 pdep = create_proc_entry(leaf->name, mask, sg_proc_sgp);
2742                 if (pdep) {
2743                         leaf->fops->owner = THIS_MODULE,
2744                         leaf->fops->read = seq_read,
2745                         leaf->fops->llseek = seq_lseek,
2746                         pdep->proc_fops = leaf->fops;
2747                 }
2748         }
2749         return 0;
2750 }
2751
2752 static void
2753 sg_proc_cleanup(void)
2754 {
2755         int k;
2756         int num_leaves =
2757             sizeof (sg_proc_leaf_arr) / sizeof (sg_proc_leaf_arr[0]);
2758
2759         if (!sg_proc_sgp)
2760                 return;
2761         for (k = 0; k < num_leaves; ++k)
2762                 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2763         remove_proc_entry(sg_proc_sg_dirname, NULL);
2764 }
2765
2766
2767 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2768 {
2769         seq_printf(s, "%d\n", *((int *)s->private));
2770         return 0;
2771 }
2772
2773 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2774 {
2775         return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2776 }
2777
2778 static ssize_t
2779 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2780                    size_t count, loff_t *off)
2781 {
2782         int num;
2783         char buff[11];
2784
2785         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2786                 return -EACCES;
2787         num = (count < 10) ? count : 10;
2788         if (copy_from_user(buff, buffer, num))
2789                 return -EFAULT;
2790         buff[num] = '\0';
2791         sg_allow_dio = simple_strtoul(buff, NULL, 10) ? 1 : 0;
2792         return count;
2793 }
2794
2795 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2796 {
2797         return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2798 }
2799
2800 static ssize_t
2801 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2802                      size_t count, loff_t *off)
2803 {
2804         int num;
2805         unsigned long k = ULONG_MAX;
2806         char buff[11];
2807
2808         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2809                 return -EACCES;
2810         num = (count < 10) ? count : 10;
2811         if (copy_from_user(buff, buffer, num))
2812                 return -EFAULT;
2813         buff[num] = '\0';
2814         k = simple_strtoul(buff, NULL, 10);
2815         if (k <= 1048576) {     /* limit "big buff" to 1 MB */
2816                 sg_big_buff = k;
2817                 return count;
2818         }
2819         return -ERANGE;
2820 }
2821
2822 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2823 {
2824         seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2825                    sg_version_date);
2826         return 0;
2827 }
2828
2829 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2830 {
2831         return single_open(file, sg_proc_seq_show_version, NULL);
2832 }
2833
2834 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2835 {
2836         seq_printf(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\t"
2837                    "online\n");
2838         return 0;
2839 }
2840
2841 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2842 {
2843         return single_open(file, sg_proc_seq_show_devhdr, NULL);
2844 }
2845
2846 struct sg_proc_deviter {
2847         loff_t  index;
2848         size_t  max;
2849 };
2850
2851 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2852 {
2853         struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2854
2855         if (! it)
2856                 return NULL;
2857         if (NULL == sg_dev_arr)
2858                 goto err1;
2859         it->index = *pos;
2860         it->max = sg_last_dev();
2861         if (it->index >= it->max)
2862                 goto err1;
2863         return it;
2864 err1:
2865         kfree(it);
2866         return NULL;
2867 }
2868
2869 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2870 {
2871         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2872
2873         *pos = ++it->index;
2874         return (it->index < it->max) ? it : NULL;
2875 }
2876
2877 static void dev_seq_stop(struct seq_file *s, void *v)
2878 {
2879         kfree (v);
2880 }
2881
2882 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2883 {
2884         return seq_open(file, &dev_seq_ops);
2885 }
2886
2887 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2888 {
2889         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2890         Sg_device *sdp;
2891         struct scsi_device *scsidp;
2892
2893         sdp = it ? sg_get_dev(it->index) : NULL;
2894         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2895                 seq_printf(s, "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n",
2896                               scsidp->host->host_no, scsidp->channel,
2897                               scsidp->id, scsidp->lun, (int) scsidp->type,
2898                               1,
2899                               (int) scsidp->queue_depth,
2900                               (int) scsidp->device_busy,
2901                               (int) scsi_device_online(scsidp));
2902         else
2903                 seq_printf(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2904         return 0;
2905 }
2906
2907 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2908 {
2909         return seq_open(file, &devstrs_seq_ops);
2910 }
2911
2912 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2913 {
2914         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2915         Sg_device *sdp;
2916         struct scsi_device *scsidp;
2917
2918         sdp = it ? sg_get_dev(it->index) : NULL;
2919         if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2920                 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2921                            scsidp->vendor, scsidp->model, scsidp->rev);
2922         else
2923                 seq_printf(s, "<no active device>\n");
2924         return 0;
2925 }
2926
2927 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2928 {
2929         int k, m, new_interface, blen, usg;
2930         Sg_request *srp;
2931         Sg_fd *fp;
2932         const sg_io_hdr_t *hp;
2933         const char * cp;
2934
2935         for (k = 0; (fp = sg_get_nth_sfp(sdp, k)); ++k) {
2936                 seq_printf(s, "   FD(%d): timeout=%dms bufflen=%d "
2937                            "(res)sgat=%d low_dma=%d\n", k + 1,
2938                            jiffies_to_msecs(fp->timeout),
2939                            fp->reserve.bufflen,
2940                            (int) fp->reserve.k_use_sg,
2941                            (int) fp->low_dma);
2942                 seq_printf(s, "   cmd_q=%d f_packid=%d k_orphan=%d closed=%d\n",
2943                            (int) fp->cmd_q, (int) fp->force_packid,
2944                            (int) fp->keep_orphan, (int) fp->closed);
2945                 for (m = 0; (srp = sg_get_nth_request(fp, m)); ++m) {
2946                         hp = &srp->header;
2947                         new_interface = (hp->interface_id == '\0') ? 0 : 1;
2948                         if (srp->res_used) {
2949                                 if (new_interface &&
2950                                     (SG_FLAG_MMAP_IO & hp->flags))
2951                                         cp = "     mmap>> ";
2952                                 else
2953                                         cp = "     rb>> ";
2954                         } else {
2955                                 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2956                                         cp = "     dio>> ";
2957                                 else
2958                                         cp = "     ";
2959                         }
2960                         seq_printf(s, cp);
2961                         blen = srp->my_cmdp ?
2962                                 srp->my_cmdp->sr_bufflen : srp->data.bufflen;
2963                         usg = srp->my_cmdp ?
2964                                 srp->my_cmdp->sr_use_sg : srp->data.k_use_sg;
2965                         seq_printf(s, srp->done ?
2966                                    ((1 == srp->done) ?  "rcv:" : "fin:")
2967                                    : (srp->my_cmdp ? "act:" : "prior:"));
2968                         seq_printf(s, " id=%d blen=%d",
2969                                    srp->header.pack_id, blen);
2970                         if (srp->done)
2971                                 seq_printf(s, " dur=%d", hp->duration);
2972                         else
2973                                 seq_printf(s, " t_o/elap=%d/%d",
2974                                   new_interface ? hp->timeout : jiffies_to_msecs(fp->timeout),
2975                                   jiffies_to_msecs(hp->duration ? (jiffies - hp->duration) : 0));
2976                         seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2977                                    (int) srp->data.cmd_opcode);
2978                 }
2979                 if (0 == m)
2980                         seq_printf(s, "     No requests active\n");
2981         }
2982 }
2983
2984 static int sg_proc_open_debug(struct inode *inode, struct file *file)
2985 {
2986         return seq_open(file, &debug_seq_ops);
2987 }
2988
2989 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2990 {
2991         struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2992         Sg_device *sdp;
2993
2994         if (it && (0 == it->index)) {
2995                 seq_printf(s, "dev_max(currently)=%d max_active_device=%d "
2996                            "(origin 1)\n", sg_dev_max, (int)it->max);
2997                 seq_printf(s, " def_reserved_size=%d\n", sg_big_buff);
2998         }
2999         sdp = it ? sg_get_dev(it->index) : NULL;
3000         if (sdp) {
3001                 struct scsi_device *scsidp = sdp->device;
3002
3003                 if (NULL == scsidp) {
3004                         seq_printf(s, "device %d detached ??\n",
3005                                    (int)it->index);
3006                         return 0;
3007                 }
3008
3009                 if (sg_get_nth_sfp(sdp, 0)) {
3010                         seq_printf(s, " >>> device=%s ",
3011                                 sdp->disk->disk_name);
3012                         if (sdp->detached)
3013                                 seq_printf(s, "detached pending close ");
3014                         else
3015                                 seq_printf
3016                                     (s, "scsi%d chan=%d id=%d lun=%d   em=%d",
3017                                      scsidp->host->host_no,
3018                                      scsidp->channel, scsidp->id,
3019                                      scsidp->lun,
3020                                      scsidp->host->hostt->emulated);
3021                         seq_printf(s, " sg_tablesize=%d excl=%d\n",
3022                                    sdp->sg_tablesize, sdp->exclude);
3023                 }
3024                 sg_proc_debug_helper(s, sdp);
3025         }
3026         return 0;
3027 }
3028
3029 #endif                          /* CONFIG_SCSI_PROC_FS */
3030
3031 module_init(init_sg);
3032 module_exit(exit_sg);
3033 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);