1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * History: 4 * Started: Aug 9 by Lawrence Foard (entropy@world.std.com), 5 * to allow user process control of SCSI devices. 6 * Development Sponsored by Killy Corp. NY NY 7 * 8 * Original driver (sg.c): 9 * Copyright (C) 1992 Lawrence Foard 10 * Version 2 and 3 extensions to driver: 11 * Copyright (C) 1998 - 2014 Douglas Gilbert 12 */ 13 14 static int sg_version_num = 30536; /* 2 digits for each component */ 15 #define SG_VERSION_STR "3.5.36" 16 17 /* 18 * D. P. Gilbert (dgilbert@interlog.com), notes: 19 * - scsi logging is available via SCSI_LOG_TIMEOUT macros. First 20 * the kernel/module needs to be built with CONFIG_SCSI_LOGGING 21 * (otherwise the macros compile to empty statements). 22 * 23 */ 24 #include <linux/module.h> 25 26 #include <linux/fs.h> 27 #include <linux/kernel.h> 28 #include <linux/sched.h> 29 #include <linux/string.h> 30 #include <linux/mm.h> 31 #include <linux/errno.h> 32 #include <linux/mtio.h> 33 #include <linux/ioctl.h> 34 #include <linux/major.h> 35 #include <linux/slab.h> 36 #include <linux/fcntl.h> 37 #include <linux/init.h> 38 #include <linux/poll.h> 39 #include <linux/moduleparam.h> 40 #include <linux/cdev.h> 41 #include <linux/idr.h> 42 #include <linux/seq_file.h> 43 #include <linux/blkdev.h> 44 #include <linux/delay.h> 45 #include <linux/blktrace_api.h> 46 #include <linux/mutex.h> 47 #include <linux/atomic.h> 48 #include <linux/ratelimit.h> 49 #include <linux/uio.h> 50 #include <linux/cred.h> /* for sg_check_file_access() */ 51 52 #include <scsi/scsi.h> 53 #include <scsi/scsi_cmnd.h> 54 #include <scsi/scsi_dbg.h> 55 #include <scsi/scsi_device.h> 56 #include <scsi/scsi_driver.h> 57 #include <scsi/scsi_eh.h> 58 #include <scsi/scsi_host.h> 59 #include <scsi/scsi_ioctl.h> 60 #include <scsi/scsi_tcq.h> 61 #include <scsi/sg.h> 62 63 #include "scsi_logging.h" 64 65 #ifdef CONFIG_SCSI_PROC_FS 66 #include <linux/proc_fs.h> 67 static char *sg_version_date = "20140603"; 68 69 static int sg_proc_init(void); 70 #endif 71 72 #define SG_ALLOW_DIO_DEF 0 73 74 #define SG_MAX_DEVS 32768 75 76 /* SG_MAX_CDB_SIZE should be 260 (spc4r37 section 3.1.30) however the type 77 * of sg_io_hdr::cmd_len can only represent 255. All SCSI commands greater 78 * than 16 bytes are "variable length" whose length is a multiple of 4 79 */ 80 #define SG_MAX_CDB_SIZE 252 81 82 #define SG_DEFAULT_TIMEOUT mult_frac(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ) 83 84 static int sg_big_buff = SG_DEF_RESERVED_SIZE; 85 /* N.B. This variable is readable and writeable via 86 /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer 87 of this size (or less if there is not enough memory) will be reserved 88 for use by this file descriptor. [Deprecated usage: this variable is also 89 readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into 90 the kernel (i.e. it is not a module).] */ 91 static int def_reserved_size = -1; /* picks up init parameter */ 92 static int sg_allow_dio = SG_ALLOW_DIO_DEF; 93 94 static int scatter_elem_sz = SG_SCATTER_SZ; 95 static int scatter_elem_sz_prev = SG_SCATTER_SZ; 96 97 #define SG_SECTOR_SZ 512 98 99 static int sg_add_device(struct device *); 100 static void sg_remove_device(struct device *); 101 102 static DEFINE_IDR(sg_index_idr); 103 static DEFINE_RWLOCK(sg_index_lock); /* Also used to lock 104 file descriptor list for device */ 105 106 static struct class_interface sg_interface = { 107 .add_dev = sg_add_device, 108 .remove_dev = sg_remove_device, 109 }; 110 111 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */ 112 unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */ 113 unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */ 114 unsigned bufflen; /* Size of (aggregate) data buffer */ 115 struct page **pages; 116 int page_order; 117 char dio_in_use; /* 0->indirect IO (or mmap), 1->dio */ 118 unsigned char cmd_opcode; /* first byte of command */ 119 } Sg_scatter_hold; 120 121 struct sg_device; /* forward declarations */ 122 struct sg_fd; 123 124 typedef struct sg_request { /* SG_MAX_QUEUE requests outstanding per file */ 125 struct list_head entry; /* list entry */ 126 struct sg_fd *parentfp; /* NULL -> not in use */ 127 Sg_scatter_hold data; /* hold buffer, perhaps scatter list */ 128 sg_io_hdr_t header; /* scsi command+info, see <scsi/sg.h> */ 129 unsigned char sense_b[SCSI_SENSE_BUFFERSIZE]; 130 char res_used; /* 1 -> using reserve buffer, 0 -> not ... */ 131 char orphan; /* 1 -> drop on sight, 0 -> normal */ 132 char sg_io_owned; /* 1 -> packet belongs to SG_IO */ 133 /* done protected by rq_list_lock */ 134 char done; /* 0->before bh, 1->before read, 2->read */ 135 struct request *rq; 136 struct bio *bio; 137 struct execute_work ew; 138 } Sg_request; 139 140 typedef struct sg_fd { /* holds the state of a file descriptor */ 141 struct list_head sfd_siblings; /* protected by device's sfd_lock */ 142 struct sg_device *parentdp; /* owning device */ 143 wait_queue_head_t read_wait; /* queue read until command done */ 144 rwlock_t rq_list_lock; /* protect access to list in req_arr */ 145 struct mutex f_mutex; /* protect against changes in this fd */ 146 int timeout; /* defaults to SG_DEFAULT_TIMEOUT */ 147 int timeout_user; /* defaults to SG_DEFAULT_TIMEOUT_USER */ 148 Sg_scatter_hold reserve; /* buffer held for this file descriptor */ 149 struct list_head rq_list; /* head of request list */ 150 struct fasync_struct *async_qp; /* used by asynchronous notification */ 151 Sg_request req_arr[SG_MAX_QUEUE]; /* used as singly-linked list */ 152 char force_packid; /* 1 -> pack_id input to read(), 0 -> ignored */ 153 char cmd_q; /* 1 -> allow command queuing, 0 -> don't */ 154 unsigned char next_cmd_len; /* 0: automatic, >0: use on next write() */ 155 char keep_orphan; /* 0 -> drop orphan (def), 1 -> keep for read() */ 156 char mmap_called; /* 0 -> mmap() never called on this fd */ 157 char res_in_use; /* 1 -> 'reserve' array in use */ 158 struct kref f_ref; 159 struct execute_work ew; 160 } Sg_fd; 161 162 typedef struct sg_device { /* holds the state of each scsi generic device */ 163 struct scsi_device *device; 164 wait_queue_head_t open_wait; /* queue open() when O_EXCL present */ 165 struct mutex open_rel_lock; /* held when in open() or release() */ 166 int sg_tablesize; /* adapter's max scatter-gather table size */ 167 u32 index; /* device index number */ 168 struct list_head sfds; 169 rwlock_t sfd_lock; /* protect access to sfd list */ 170 atomic_t detaching; /* 0->device usable, 1->device detaching */ 171 bool exclude; /* 1->open(O_EXCL) succeeded and is active */ 172 int open_cnt; /* count of opens (perhaps < num(sfds) ) */ 173 char sgdebug; /* 0->off, 1->sense, 9->dump dev, 10-> all devs */ 174 char name[DISK_NAME_LEN]; 175 struct cdev * cdev; /* char_dev [sysfs: /sys/cdev/major/sg<n>] */ 176 struct kref d_ref; 177 } Sg_device; 178 179 /* tasklet or soft irq callback */ 180 static enum rq_end_io_ret sg_rq_end_io(struct request *rq, blk_status_t status); 181 static int sg_start_req(Sg_request *srp, unsigned char *cmd); 182 static int sg_finish_rem_req(Sg_request * srp); 183 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size); 184 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, 185 Sg_request * srp); 186 static ssize_t sg_new_write(Sg_fd *sfp, struct file *file, 187 const char __user *buf, size_t count, int blocking, 188 int read_only, int sg_io_owned, 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_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer); 192 static void sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp); 193 static void sg_build_reserve(Sg_fd * sfp, int req_size); 194 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size); 195 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp); 196 static Sg_fd *sg_add_sfp(Sg_device * sdp); 197 static void sg_remove_sfp(struct kref *); 198 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id, bool *busy); 199 static Sg_request *sg_add_request(Sg_fd * sfp); 200 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp); 201 static Sg_device *sg_get_dev(int dev); 202 static void sg_device_destroy(struct kref *kref); 203 204 #define SZ_SG_HEADER sizeof(struct sg_header) 205 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t) 206 #define SZ_SG_IOVEC sizeof(sg_iovec_t) 207 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t) 208 209 #define sg_printk(prefix, sdp, fmt, a...) \ 210 sdev_prefix_printk(prefix, (sdp)->device, (sdp)->name, fmt, ##a) 211 212 /* 213 * The SCSI interfaces that use read() and write() as an asynchronous variant of 214 * ioctl(..., SG_IO, ...) are fundamentally unsafe, since there are lots of ways 215 * to trigger read() and write() calls from various contexts with elevated 216 * privileges. This can lead to kernel memory corruption (e.g. if these 217 * interfaces are called through splice()) and privilege escalation inside 218 * userspace (e.g. if a process with access to such a device passes a file 219 * descriptor to a SUID binary as stdin/stdout/stderr). 220 * 221 * This function provides protection for the legacy API by restricting the 222 * calling context. 223 */ 224 static int sg_check_file_access(struct file *filp, const char *caller) 225 { 226 if (filp->f_cred != current_real_cred()) { 227 pr_err_once("%s: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n", 228 caller, task_tgid_vnr(current), current->comm); 229 return -EPERM; 230 } 231 return 0; 232 } 233 234 static int sg_allow_access(struct file *filp, unsigned char *cmd) 235 { 236 struct sg_fd *sfp = filp->private_data; 237 238 if (sfp->parentdp->device->type == TYPE_SCANNER) 239 return 0; 240 if (!scsi_cmd_allowed(cmd, filp->f_mode)) 241 return -EPERM; 242 return 0; 243 } 244 245 static int 246 open_wait(Sg_device *sdp, int flags) 247 { 248 int retval = 0; 249 250 if (flags & O_EXCL) { 251 while (sdp->open_cnt > 0) { 252 mutex_unlock(&sdp->open_rel_lock); 253 retval = wait_event_interruptible(sdp->open_wait, 254 (atomic_read(&sdp->detaching) || 255 !sdp->open_cnt)); 256 mutex_lock(&sdp->open_rel_lock); 257 258 if (retval) /* -ERESTARTSYS */ 259 return retval; 260 if (atomic_read(&sdp->detaching)) 261 return -ENODEV; 262 } 263 } else { 264 while (sdp->exclude) { 265 mutex_unlock(&sdp->open_rel_lock); 266 retval = wait_event_interruptible(sdp->open_wait, 267 (atomic_read(&sdp->detaching) || 268 !sdp->exclude)); 269 mutex_lock(&sdp->open_rel_lock); 270 271 if (retval) /* -ERESTARTSYS */ 272 return retval; 273 if (atomic_read(&sdp->detaching)) 274 return -ENODEV; 275 } 276 } 277 278 return retval; 279 } 280 281 /* Returns 0 on success, else a negated errno value */ 282 static int 283 sg_open(struct inode *inode, struct file *filp) 284 { 285 int dev = iminor(inode); 286 int flags = filp->f_flags; 287 struct request_queue *q; 288 Sg_device *sdp; 289 Sg_fd *sfp; 290 int retval; 291 292 nonseekable_open(inode, filp); 293 if ((flags & O_EXCL) && (O_RDONLY == (flags & O_ACCMODE))) 294 return -EPERM; /* Can't lock it with read only access */ 295 sdp = sg_get_dev(dev); 296 if (IS_ERR(sdp)) 297 return PTR_ERR(sdp); 298 299 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 300 "sg_open: flags=0x%x\n", flags)); 301 302 /* This driver's module count bumped by fops_get in <linux/fs.h> */ 303 /* Prevent the device driver from vanishing while we sleep */ 304 retval = scsi_device_get(sdp->device); 305 if (retval) 306 goto sg_put; 307 308 retval = scsi_autopm_get_device(sdp->device); 309 if (retval) 310 goto sdp_put; 311 312 /* scsi_block_when_processing_errors() may block so bypass 313 * check if O_NONBLOCK. Permits SCSI commands to be issued 314 * during error recovery. Tread carefully. */ 315 if (!((flags & O_NONBLOCK) || 316 scsi_block_when_processing_errors(sdp->device))) { 317 retval = -ENXIO; 318 /* we are in error recovery for this device */ 319 goto error_out; 320 } 321 322 mutex_lock(&sdp->open_rel_lock); 323 if (flags & O_NONBLOCK) { 324 if (flags & O_EXCL) { 325 if (sdp->open_cnt > 0) { 326 retval = -EBUSY; 327 goto error_mutex_locked; 328 } 329 } else { 330 if (sdp->exclude) { 331 retval = -EBUSY; 332 goto error_mutex_locked; 333 } 334 } 335 } else { 336 retval = open_wait(sdp, flags); 337 if (retval) /* -ERESTARTSYS or -ENODEV */ 338 goto error_mutex_locked; 339 } 340 341 /* N.B. at this point we are holding the open_rel_lock */ 342 if (flags & O_EXCL) 343 sdp->exclude = true; 344 345 if (sdp->open_cnt < 1) { /* no existing opens */ 346 sdp->sgdebug = 0; 347 q = sdp->device->request_queue; 348 sdp->sg_tablesize = queue_max_segments(q); 349 } 350 sfp = sg_add_sfp(sdp); 351 if (IS_ERR(sfp)) { 352 retval = PTR_ERR(sfp); 353 goto out_undo; 354 } 355 356 filp->private_data = sfp; 357 sdp->open_cnt++; 358 mutex_unlock(&sdp->open_rel_lock); 359 360 retval = 0; 361 sg_put: 362 kref_put(&sdp->d_ref, sg_device_destroy); 363 return retval; 364 365 out_undo: 366 if (flags & O_EXCL) { 367 sdp->exclude = false; /* undo if error */ 368 wake_up_interruptible(&sdp->open_wait); 369 } 370 error_mutex_locked: 371 mutex_unlock(&sdp->open_rel_lock); 372 error_out: 373 scsi_autopm_put_device(sdp->device); 374 sdp_put: 375 scsi_device_put(sdp->device); 376 goto sg_put; 377 } 378 379 /* Release resources associated with a successful sg_open() 380 * Returns 0 on success, else a negated errno value */ 381 static int 382 sg_release(struct inode *inode, struct file *filp) 383 { 384 Sg_device *sdp; 385 Sg_fd *sfp; 386 387 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 388 return -ENXIO; 389 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, "sg_release\n")); 390 391 mutex_lock(&sdp->open_rel_lock); 392 scsi_autopm_put_device(sdp->device); 393 kref_put(&sfp->f_ref, sg_remove_sfp); 394 sdp->open_cnt--; 395 396 /* possibly many open()s waiting on exlude clearing, start many; 397 * only open(O_EXCL)s wait on 0==open_cnt so only start one */ 398 if (sdp->exclude) { 399 sdp->exclude = false; 400 wake_up_interruptible_all(&sdp->open_wait); 401 } else if (0 == sdp->open_cnt) { 402 wake_up_interruptible(&sdp->open_wait); 403 } 404 mutex_unlock(&sdp->open_rel_lock); 405 return 0; 406 } 407 408 static int get_sg_io_pack_id(int *pack_id, void __user *buf, size_t count) 409 { 410 struct sg_header __user *old_hdr = buf; 411 int reply_len; 412 413 if (count >= SZ_SG_HEADER) { 414 /* negative reply_len means v3 format, otherwise v1/v2 */ 415 if (get_user(reply_len, &old_hdr->reply_len)) 416 return -EFAULT; 417 418 if (reply_len >= 0) 419 return get_user(*pack_id, &old_hdr->pack_id); 420 421 if (in_compat_syscall() && 422 count >= sizeof(struct compat_sg_io_hdr)) { 423 struct compat_sg_io_hdr __user *hp = buf; 424 425 return get_user(*pack_id, &hp->pack_id); 426 } 427 428 if (count >= sizeof(struct sg_io_hdr)) { 429 struct sg_io_hdr __user *hp = buf; 430 431 return get_user(*pack_id, &hp->pack_id); 432 } 433 } 434 435 /* no valid header was passed, so ignore the pack_id */ 436 *pack_id = -1; 437 return 0; 438 } 439 440 static ssize_t 441 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos) 442 { 443 Sg_device *sdp; 444 Sg_fd *sfp; 445 Sg_request *srp; 446 int req_pack_id = -1; 447 bool busy; 448 sg_io_hdr_t *hp; 449 struct sg_header *old_hdr; 450 int retval; 451 452 /* 453 * This could cause a response to be stranded. Close the associated 454 * file descriptor to free up any resources being held. 455 */ 456 retval = sg_check_file_access(filp, __func__); 457 if (retval) 458 return retval; 459 460 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 461 return -ENXIO; 462 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 463 "sg_read: count=%d\n", (int) count)); 464 465 if (sfp->force_packid) 466 retval = get_sg_io_pack_id(&req_pack_id, buf, count); 467 if (retval) 468 return retval; 469 470 srp = sg_get_rq_mark(sfp, req_pack_id, &busy); 471 if (!srp) { /* now wait on packet to arrive */ 472 if (filp->f_flags & O_NONBLOCK) 473 return -EAGAIN; 474 retval = wait_event_interruptible(sfp->read_wait, 475 ((srp = sg_get_rq_mark(sfp, req_pack_id, &busy)) || 476 (!busy && atomic_read(&sdp->detaching)))); 477 if (!srp) 478 /* signal or detaching */ 479 return retval ? retval : -ENODEV; 480 } 481 if (srp->header.interface_id != '\0') 482 return sg_new_read(sfp, buf, count, srp); 483 484 hp = &srp->header; 485 old_hdr = kzalloc(SZ_SG_HEADER, GFP_KERNEL); 486 if (!old_hdr) 487 return -ENOMEM; 488 489 old_hdr->reply_len = (int) hp->timeout; 490 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */ 491 old_hdr->pack_id = hp->pack_id; 492 old_hdr->twelve_byte = 493 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0; 494 old_hdr->target_status = hp->masked_status; 495 old_hdr->host_status = hp->host_status; 496 old_hdr->driver_status = hp->driver_status; 497 if ((CHECK_CONDITION & hp->masked_status) || 498 (srp->sense_b[0] & 0x70) == 0x70) { 499 old_hdr->driver_status = DRIVER_SENSE; 500 memcpy(old_hdr->sense_buffer, srp->sense_b, 501 sizeof (old_hdr->sense_buffer)); 502 } 503 switch (hp->host_status) { 504 /* This setup of 'result' is for backward compatibility and is best 505 ignored by the user who should use target, host + driver status */ 506 case DID_OK: 507 case DID_PASSTHROUGH: 508 case DID_SOFT_ERROR: 509 old_hdr->result = 0; 510 break; 511 case DID_NO_CONNECT: 512 case DID_BUS_BUSY: 513 case DID_TIME_OUT: 514 old_hdr->result = EBUSY; 515 break; 516 case DID_BAD_TARGET: 517 case DID_ABORT: 518 case DID_PARITY: 519 case DID_RESET: 520 case DID_BAD_INTR: 521 old_hdr->result = EIO; 522 break; 523 case DID_ERROR: 524 old_hdr->result = (srp->sense_b[0] == 0 && 525 hp->masked_status == GOOD) ? 0 : EIO; 526 break; 527 default: 528 old_hdr->result = EIO; 529 break; 530 } 531 532 /* Now copy the result back to the user buffer. */ 533 if (count >= SZ_SG_HEADER) { 534 if (copy_to_user(buf, old_hdr, SZ_SG_HEADER)) { 535 retval = -EFAULT; 536 goto free_old_hdr; 537 } 538 buf += SZ_SG_HEADER; 539 if (count > old_hdr->reply_len) 540 count = old_hdr->reply_len; 541 if (count > SZ_SG_HEADER) { 542 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) { 543 retval = -EFAULT; 544 goto free_old_hdr; 545 } 546 } 547 } else 548 count = (old_hdr->result == 0) ? 0 : -EIO; 549 sg_finish_rem_req(srp); 550 sg_remove_request(sfp, srp); 551 retval = count; 552 free_old_hdr: 553 kfree(old_hdr); 554 return retval; 555 } 556 557 static ssize_t 558 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp) 559 { 560 sg_io_hdr_t *hp = &srp->header; 561 int err = 0, err2; 562 int len; 563 564 if (in_compat_syscall()) { 565 if (count < sizeof(struct compat_sg_io_hdr)) { 566 err = -EINVAL; 567 goto err_out; 568 } 569 } else if (count < SZ_SG_IO_HDR) { 570 err = -EINVAL; 571 goto err_out; 572 } 573 hp->sb_len_wr = 0; 574 if ((hp->mx_sb_len > 0) && hp->sbp) { 575 if ((CHECK_CONDITION & hp->masked_status) || 576 (srp->sense_b[0] & 0x70) == 0x70) { 577 int sb_len = SCSI_SENSE_BUFFERSIZE; 578 sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len; 579 len = 8 + (int) srp->sense_b[7]; /* Additional sense length field */ 580 len = (len > sb_len) ? sb_len : len; 581 if (copy_to_user(hp->sbp, srp->sense_b, len)) { 582 err = -EFAULT; 583 goto err_out; 584 } 585 hp->driver_status = DRIVER_SENSE; 586 hp->sb_len_wr = len; 587 } 588 } 589 if (hp->masked_status || hp->host_status || hp->driver_status) 590 hp->info |= SG_INFO_CHECK; 591 err = put_sg_io_hdr(hp, buf); 592 err_out: 593 err2 = sg_finish_rem_req(srp); 594 sg_remove_request(sfp, srp); 595 return err ? : err2 ? : count; 596 } 597 598 static ssize_t 599 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos) 600 { 601 int mxsize, cmd_size, k; 602 int input_size, blocking; 603 unsigned char opcode; 604 Sg_device *sdp; 605 Sg_fd *sfp; 606 Sg_request *srp; 607 struct sg_header old_hdr; 608 sg_io_hdr_t *hp; 609 unsigned char cmnd[SG_MAX_CDB_SIZE]; 610 int retval; 611 612 retval = sg_check_file_access(filp, __func__); 613 if (retval) 614 return retval; 615 616 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 617 return -ENXIO; 618 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 619 "sg_write: count=%d\n", (int) count)); 620 if (atomic_read(&sdp->detaching)) 621 return -ENODEV; 622 if (!((filp->f_flags & O_NONBLOCK) || 623 scsi_block_when_processing_errors(sdp->device))) 624 return -ENXIO; 625 626 if (count < SZ_SG_HEADER) 627 return -EIO; 628 if (copy_from_user(&old_hdr, buf, SZ_SG_HEADER)) 629 return -EFAULT; 630 blocking = !(filp->f_flags & O_NONBLOCK); 631 if (old_hdr.reply_len < 0) 632 return sg_new_write(sfp, filp, buf, count, 633 blocking, 0, 0, NULL); 634 if (count < (SZ_SG_HEADER + 6)) 635 return -EIO; /* The minimum scsi command length is 6 bytes. */ 636 637 buf += SZ_SG_HEADER; 638 if (get_user(opcode, buf)) 639 return -EFAULT; 640 641 if (!(srp = sg_add_request(sfp))) { 642 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sdp, 643 "sg_write: queue full\n")); 644 return -EDOM; 645 } 646 mutex_lock(&sfp->f_mutex); 647 if (sfp->next_cmd_len > 0) { 648 cmd_size = sfp->next_cmd_len; 649 sfp->next_cmd_len = 0; /* reset so only this write() effected */ 650 } else { 651 cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */ 652 if ((opcode >= 0xc0) && old_hdr.twelve_byte) 653 cmd_size = 12; 654 } 655 mutex_unlock(&sfp->f_mutex); 656 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp, 657 "sg_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size)); 658 /* Determine buffer size. */ 659 input_size = count - cmd_size; 660 mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len; 661 mxsize -= SZ_SG_HEADER; 662 input_size -= SZ_SG_HEADER; 663 if (input_size < 0) { 664 sg_remove_request(sfp, srp); 665 return -EIO; /* User did not pass enough bytes for this command. */ 666 } 667 hp = &srp->header; 668 hp->interface_id = '\0'; /* indicator of old interface tunnelled */ 669 hp->cmd_len = (unsigned char) cmd_size; 670 hp->iovec_count = 0; 671 hp->mx_sb_len = 0; 672 if (input_size > 0) 673 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ? 674 SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV; 675 else 676 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE; 677 hp->dxfer_len = mxsize; 678 if ((hp->dxfer_direction == SG_DXFER_TO_DEV) || 679 (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV)) 680 hp->dxferp = (char __user *)buf + cmd_size; 681 else 682 hp->dxferp = NULL; 683 hp->sbp = NULL; 684 hp->timeout = old_hdr.reply_len; /* structure abuse ... */ 685 hp->flags = input_size; /* structure abuse ... */ 686 hp->pack_id = old_hdr.pack_id; 687 hp->usr_ptr = NULL; 688 if (copy_from_user(cmnd, buf, cmd_size)) { 689 sg_remove_request(sfp, srp); 690 return -EFAULT; 691 } 692 /* 693 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV, 694 * but is is possible that the app intended SG_DXFER_TO_DEV, because there 695 * is a non-zero input_size, so emit a warning. 696 */ 697 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) { 698 printk_ratelimited(KERN_WARNING 699 "sg_write: data in/out %d/%d bytes " 700 "for SCSI command 0x%x-- guessing " 701 "data in;\n program %s not setting " 702 "count and/or reply_len properly\n", 703 old_hdr.reply_len - (int)SZ_SG_HEADER, 704 input_size, (unsigned int) cmnd[0], 705 current->comm); 706 } 707 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking); 708 return (k < 0) ? k : count; 709 } 710 711 static ssize_t 712 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf, 713 size_t count, int blocking, int read_only, int sg_io_owned, 714 Sg_request **o_srp) 715 { 716 int k; 717 Sg_request *srp; 718 sg_io_hdr_t *hp; 719 unsigned char cmnd[SG_MAX_CDB_SIZE]; 720 int timeout; 721 unsigned long ul_timeout; 722 723 if (count < SZ_SG_IO_HDR) 724 return -EINVAL; 725 726 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */ 727 if (!(srp = sg_add_request(sfp))) { 728 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp, 729 "sg_new_write: queue full\n")); 730 return -EDOM; 731 } 732 srp->sg_io_owned = sg_io_owned; 733 hp = &srp->header; 734 if (get_sg_io_hdr(hp, buf)) { 735 sg_remove_request(sfp, srp); 736 return -EFAULT; 737 } 738 if (hp->interface_id != 'S') { 739 sg_remove_request(sfp, srp); 740 return -ENOSYS; 741 } 742 if (hp->flags & SG_FLAG_MMAP_IO) { 743 if (hp->dxfer_len > sfp->reserve.bufflen) { 744 sg_remove_request(sfp, srp); 745 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */ 746 } 747 if (hp->flags & SG_FLAG_DIRECT_IO) { 748 sg_remove_request(sfp, srp); 749 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */ 750 } 751 if (sfp->res_in_use) { 752 sg_remove_request(sfp, srp); 753 return -EBUSY; /* reserve buffer already being used */ 754 } 755 } 756 ul_timeout = msecs_to_jiffies(srp->header.timeout); 757 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX; 758 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) { 759 sg_remove_request(sfp, srp); 760 return -EMSGSIZE; 761 } 762 if (copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) { 763 sg_remove_request(sfp, srp); 764 return -EFAULT; 765 } 766 if (read_only && sg_allow_access(file, cmnd)) { 767 sg_remove_request(sfp, srp); 768 return -EPERM; 769 } 770 k = sg_common_write(sfp, srp, cmnd, timeout, blocking); 771 if (k < 0) 772 return k; 773 if (o_srp) 774 *o_srp = srp; 775 return count; 776 } 777 778 static int 779 sg_common_write(Sg_fd * sfp, Sg_request * srp, 780 unsigned char *cmnd, int timeout, int blocking) 781 { 782 int k, at_head; 783 Sg_device *sdp = sfp->parentdp; 784 sg_io_hdr_t *hp = &srp->header; 785 786 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */ 787 hp->status = 0; 788 hp->masked_status = 0; 789 hp->msg_status = 0; 790 hp->info = 0; 791 hp->host_status = 0; 792 hp->driver_status = 0; 793 hp->resid = 0; 794 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 795 "sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n", 796 (int) cmnd[0], (int) hp->cmd_len)); 797 798 if (hp->dxfer_len >= SZ_256M) { 799 sg_remove_request(sfp, srp); 800 return -EINVAL; 801 } 802 803 k = sg_start_req(srp, cmnd); 804 if (k) { 805 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp, 806 "sg_common_write: start_req err=%d\n", k)); 807 sg_finish_rem_req(srp); 808 sg_remove_request(sfp, srp); 809 return k; /* probably out of space --> ENOMEM */ 810 } 811 if (atomic_read(&sdp->detaching)) { 812 if (srp->bio) { 813 blk_mq_free_request(srp->rq); 814 srp->rq = NULL; 815 } 816 817 sg_finish_rem_req(srp); 818 sg_remove_request(sfp, srp); 819 return -ENODEV; 820 } 821 822 hp->duration = jiffies_to_msecs(jiffies); 823 if (hp->interface_id != '\0' && /* v3 (or later) interface */ 824 (SG_FLAG_Q_AT_TAIL & hp->flags)) 825 at_head = 0; 826 else 827 at_head = 1; 828 829 srp->rq->timeout = timeout; 830 kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */ 831 srp->rq->end_io = sg_rq_end_io; 832 blk_execute_rq_nowait(srp->rq, at_head); 833 return 0; 834 } 835 836 static int srp_done(Sg_fd *sfp, Sg_request *srp) 837 { 838 unsigned long flags; 839 int ret; 840 841 read_lock_irqsave(&sfp->rq_list_lock, flags); 842 ret = srp->done; 843 read_unlock_irqrestore(&sfp->rq_list_lock, flags); 844 return ret; 845 } 846 847 static int max_sectors_bytes(struct request_queue *q) 848 { 849 unsigned int max_sectors = queue_max_sectors(q); 850 851 max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9); 852 853 return max_sectors << 9; 854 } 855 856 static void 857 sg_fill_request_table(Sg_fd *sfp, sg_req_info_t *rinfo) 858 { 859 Sg_request *srp; 860 int val; 861 unsigned int ms; 862 863 val = 0; 864 list_for_each_entry(srp, &sfp->rq_list, entry) { 865 if (val >= SG_MAX_QUEUE) 866 break; 867 rinfo[val].req_state = srp->done + 1; 868 rinfo[val].problem = 869 srp->header.masked_status & 870 srp->header.host_status & 871 srp->header.driver_status; 872 if (srp->done) 873 rinfo[val].duration = 874 srp->header.duration; 875 else { 876 ms = jiffies_to_msecs(jiffies); 877 rinfo[val].duration = 878 (ms > srp->header.duration) ? 879 (ms - srp->header.duration) : 0; 880 } 881 rinfo[val].orphan = srp->orphan; 882 rinfo[val].sg_io_owned = srp->sg_io_owned; 883 rinfo[val].pack_id = srp->header.pack_id; 884 rinfo[val].usr_ptr = srp->header.usr_ptr; 885 val++; 886 } 887 } 888 889 #ifdef CONFIG_COMPAT 890 struct compat_sg_req_info { /* used by SG_GET_REQUEST_TABLE ioctl() */ 891 char req_state; 892 char orphan; 893 char sg_io_owned; 894 char problem; 895 int pack_id; 896 compat_uptr_t usr_ptr; 897 unsigned int duration; 898 int unused; 899 }; 900 901 static int put_compat_request_table(struct compat_sg_req_info __user *o, 902 struct sg_req_info *rinfo) 903 { 904 int i; 905 for (i = 0; i < SG_MAX_QUEUE; i++) { 906 if (copy_to_user(o + i, rinfo + i, offsetof(sg_req_info_t, usr_ptr)) || 907 put_user((uintptr_t)rinfo[i].usr_ptr, &o[i].usr_ptr) || 908 put_user(rinfo[i].duration, &o[i].duration) || 909 put_user(rinfo[i].unused, &o[i].unused)) 910 return -EFAULT; 911 } 912 return 0; 913 } 914 #endif 915 916 static long 917 sg_ioctl_common(struct file *filp, Sg_device *sdp, Sg_fd *sfp, 918 unsigned int cmd_in, void __user *p) 919 { 920 int __user *ip = p; 921 int result, val, read_only; 922 Sg_request *srp; 923 unsigned long iflags; 924 925 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 926 "sg_ioctl: cmd=0x%x\n", (int) cmd_in)); 927 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE)); 928 929 switch (cmd_in) { 930 case SG_IO: 931 if (atomic_read(&sdp->detaching)) 932 return -ENODEV; 933 if (!scsi_block_when_processing_errors(sdp->device)) 934 return -ENXIO; 935 result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR, 936 1, read_only, 1, &srp); 937 if (result < 0) 938 return result; 939 result = wait_event_interruptible(sfp->read_wait, 940 srp_done(sfp, srp)); 941 write_lock_irq(&sfp->rq_list_lock); 942 if (srp->done) { 943 srp->done = 2; 944 write_unlock_irq(&sfp->rq_list_lock); 945 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp); 946 return (result < 0) ? result : 0; 947 } 948 srp->orphan = 1; 949 write_unlock_irq(&sfp->rq_list_lock); 950 return result; /* -ERESTARTSYS because signal hit process */ 951 case SG_SET_TIMEOUT: 952 result = get_user(val, ip); 953 if (result) 954 return result; 955 if (val < 0) 956 return -EIO; 957 if (val >= mult_frac((s64)INT_MAX, USER_HZ, HZ)) 958 val = min_t(s64, mult_frac((s64)INT_MAX, USER_HZ, HZ), 959 INT_MAX); 960 sfp->timeout_user = val; 961 sfp->timeout = mult_frac(val, HZ, USER_HZ); 962 963 return 0; 964 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */ 965 /* strange ..., for backward compatibility */ 966 return sfp->timeout_user; 967 case SG_SET_FORCE_LOW_DMA: 968 /* 969 * N.B. This ioctl never worked properly, but failed to 970 * return an error value. So returning '0' to keep compability 971 * with legacy applications. 972 */ 973 return 0; 974 case SG_GET_LOW_DMA: 975 return put_user(0, ip); 976 case SG_GET_SCSI_ID: 977 { 978 sg_scsi_id_t v; 979 980 if (atomic_read(&sdp->detaching)) 981 return -ENODEV; 982 memset(&v, 0, sizeof(v)); 983 v.host_no = sdp->device->host->host_no; 984 v.channel = sdp->device->channel; 985 v.scsi_id = sdp->device->id; 986 v.lun = sdp->device->lun; 987 v.scsi_type = sdp->device->type; 988 v.h_cmd_per_lun = sdp->device->host->cmd_per_lun; 989 v.d_queue_depth = sdp->device->queue_depth; 990 if (copy_to_user(p, &v, sizeof(sg_scsi_id_t))) 991 return -EFAULT; 992 return 0; 993 } 994 case SG_SET_FORCE_PACK_ID: 995 result = get_user(val, ip); 996 if (result) 997 return result; 998 sfp->force_packid = val ? 1 : 0; 999 return 0; 1000 case SG_GET_PACK_ID: 1001 read_lock_irqsave(&sfp->rq_list_lock, iflags); 1002 list_for_each_entry(srp, &sfp->rq_list, entry) { 1003 if ((1 == srp->done) && (!srp->sg_io_owned)) { 1004 read_unlock_irqrestore(&sfp->rq_list_lock, 1005 iflags); 1006 return put_user(srp->header.pack_id, ip); 1007 } 1008 } 1009 read_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1010 return put_user(-1, ip); 1011 case SG_GET_NUM_WAITING: 1012 read_lock_irqsave(&sfp->rq_list_lock, iflags); 1013 val = 0; 1014 list_for_each_entry(srp, &sfp->rq_list, entry) { 1015 if ((1 == srp->done) && (!srp->sg_io_owned)) 1016 ++val; 1017 } 1018 read_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1019 return put_user(val, ip); 1020 case SG_GET_SG_TABLESIZE: 1021 return put_user(sdp->sg_tablesize, ip); 1022 case SG_SET_RESERVED_SIZE: 1023 result = get_user(val, ip); 1024 if (result) 1025 return result; 1026 if (val < 0) 1027 return -EINVAL; 1028 val = min_t(int, val, 1029 max_sectors_bytes(sdp->device->request_queue)); 1030 mutex_lock(&sfp->f_mutex); 1031 if (val != sfp->reserve.bufflen) { 1032 if (sfp->mmap_called || 1033 sfp->res_in_use) { 1034 mutex_unlock(&sfp->f_mutex); 1035 return -EBUSY; 1036 } 1037 1038 sg_remove_scat(sfp, &sfp->reserve); 1039 sg_build_reserve(sfp, val); 1040 } 1041 mutex_unlock(&sfp->f_mutex); 1042 return 0; 1043 case SG_GET_RESERVED_SIZE: 1044 val = min_t(int, sfp->reserve.bufflen, 1045 max_sectors_bytes(sdp->device->request_queue)); 1046 return put_user(val, ip); 1047 case SG_SET_COMMAND_Q: 1048 result = get_user(val, ip); 1049 if (result) 1050 return result; 1051 sfp->cmd_q = val ? 1 : 0; 1052 return 0; 1053 case SG_GET_COMMAND_Q: 1054 return put_user((int) sfp->cmd_q, ip); 1055 case SG_SET_KEEP_ORPHAN: 1056 result = get_user(val, ip); 1057 if (result) 1058 return result; 1059 sfp->keep_orphan = val; 1060 return 0; 1061 case SG_GET_KEEP_ORPHAN: 1062 return put_user((int) sfp->keep_orphan, ip); 1063 case SG_NEXT_CMD_LEN: 1064 result = get_user(val, ip); 1065 if (result) 1066 return result; 1067 if (val > SG_MAX_CDB_SIZE) 1068 return -ENOMEM; 1069 sfp->next_cmd_len = (val > 0) ? val : 0; 1070 return 0; 1071 case SG_GET_VERSION_NUM: 1072 return put_user(sg_version_num, ip); 1073 case SG_GET_ACCESS_COUNT: 1074 /* faked - we don't have a real access count anymore */ 1075 val = (sdp->device ? 1 : 0); 1076 return put_user(val, ip); 1077 case SG_GET_REQUEST_TABLE: 1078 { 1079 sg_req_info_t *rinfo; 1080 1081 rinfo = kcalloc(SG_MAX_QUEUE, SZ_SG_REQ_INFO, 1082 GFP_KERNEL); 1083 if (!rinfo) 1084 return -ENOMEM; 1085 read_lock_irqsave(&sfp->rq_list_lock, iflags); 1086 sg_fill_request_table(sfp, rinfo); 1087 read_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1088 #ifdef CONFIG_COMPAT 1089 if (in_compat_syscall()) 1090 result = put_compat_request_table(p, rinfo); 1091 else 1092 #endif 1093 result = copy_to_user(p, rinfo, 1094 SZ_SG_REQ_INFO * SG_MAX_QUEUE); 1095 result = result ? -EFAULT : 0; 1096 kfree(rinfo); 1097 return result; 1098 } 1099 case SG_EMULATED_HOST: 1100 if (atomic_read(&sdp->detaching)) 1101 return -ENODEV; 1102 return put_user(sdp->device->host->hostt->emulated, ip); 1103 case SCSI_IOCTL_SEND_COMMAND: 1104 if (atomic_read(&sdp->detaching)) 1105 return -ENODEV; 1106 return scsi_ioctl(sdp->device, filp->f_mode, cmd_in, p); 1107 case SG_SET_DEBUG: 1108 result = get_user(val, ip); 1109 if (result) 1110 return result; 1111 sdp->sgdebug = (char) val; 1112 return 0; 1113 case BLKSECTGET: 1114 return put_user(max_sectors_bytes(sdp->device->request_queue), 1115 ip); 1116 case BLKTRACESETUP: 1117 return blk_trace_setup(sdp->device->request_queue, sdp->name, 1118 MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1119 NULL, p); 1120 case BLKTRACESTART: 1121 return blk_trace_startstop(sdp->device->request_queue, 1); 1122 case BLKTRACESTOP: 1123 return blk_trace_startstop(sdp->device->request_queue, 0); 1124 case BLKTRACETEARDOWN: 1125 return blk_trace_remove(sdp->device->request_queue); 1126 case SCSI_IOCTL_GET_IDLUN: 1127 case SCSI_IOCTL_GET_BUS_NUMBER: 1128 case SCSI_IOCTL_PROBE_HOST: 1129 case SG_GET_TRANSFORM: 1130 case SG_SCSI_RESET: 1131 if (atomic_read(&sdp->detaching)) 1132 return -ENODEV; 1133 break; 1134 default: 1135 if (read_only) 1136 return -EPERM; /* don't know so take safe approach */ 1137 break; 1138 } 1139 1140 result = scsi_ioctl_block_when_processing_errors(sdp->device, 1141 cmd_in, filp->f_flags & O_NDELAY); 1142 if (result) 1143 return result; 1144 1145 return -ENOIOCTLCMD; 1146 } 1147 1148 static long 1149 sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg) 1150 { 1151 void __user *p = (void __user *)arg; 1152 Sg_device *sdp; 1153 Sg_fd *sfp; 1154 int ret; 1155 1156 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 1157 return -ENXIO; 1158 1159 ret = sg_ioctl_common(filp, sdp, sfp, cmd_in, p); 1160 if (ret != -ENOIOCTLCMD) 1161 return ret; 1162 return scsi_ioctl(sdp->device, filp->f_mode, cmd_in, p); 1163 } 1164 1165 static __poll_t 1166 sg_poll(struct file *filp, poll_table * wait) 1167 { 1168 __poll_t res = 0; 1169 Sg_device *sdp; 1170 Sg_fd *sfp; 1171 Sg_request *srp; 1172 int count = 0; 1173 unsigned long iflags; 1174 1175 sfp = filp->private_data; 1176 if (!sfp) 1177 return EPOLLERR; 1178 sdp = sfp->parentdp; 1179 if (!sdp) 1180 return EPOLLERR; 1181 poll_wait(filp, &sfp->read_wait, wait); 1182 read_lock_irqsave(&sfp->rq_list_lock, iflags); 1183 list_for_each_entry(srp, &sfp->rq_list, entry) { 1184 /* if any read waiting, flag it */ 1185 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned)) 1186 res = EPOLLIN | EPOLLRDNORM; 1187 ++count; 1188 } 1189 read_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1190 1191 if (atomic_read(&sdp->detaching)) 1192 res |= EPOLLHUP; 1193 else if (!sfp->cmd_q) { 1194 if (0 == count) 1195 res |= EPOLLOUT | EPOLLWRNORM; 1196 } else if (count < SG_MAX_QUEUE) 1197 res |= EPOLLOUT | EPOLLWRNORM; 1198 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 1199 "sg_poll: res=0x%x\n", (__force u32) res)); 1200 return res; 1201 } 1202 1203 static int 1204 sg_fasync(int fd, struct file *filp, int mode) 1205 { 1206 Sg_device *sdp; 1207 Sg_fd *sfp; 1208 1209 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 1210 return -ENXIO; 1211 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 1212 "sg_fasync: mode=%d\n", mode)); 1213 1214 return fasync_helper(fd, filp, mode, &sfp->async_qp); 1215 } 1216 1217 static vm_fault_t 1218 sg_vma_fault(struct vm_fault *vmf) 1219 { 1220 struct vm_area_struct *vma = vmf->vma; 1221 Sg_fd *sfp; 1222 unsigned long offset, len, sa; 1223 Sg_scatter_hold *rsv_schp; 1224 int k, length; 1225 1226 if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data))) 1227 return VM_FAULT_SIGBUS; 1228 rsv_schp = &sfp->reserve; 1229 offset = vmf->pgoff << PAGE_SHIFT; 1230 if (offset >= rsv_schp->bufflen) 1231 return VM_FAULT_SIGBUS; 1232 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp, 1233 "sg_vma_fault: offset=%lu, scatg=%d\n", 1234 offset, rsv_schp->k_use_sg)); 1235 sa = vma->vm_start; 1236 length = 1 << (PAGE_SHIFT + rsv_schp->page_order); 1237 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) { 1238 len = vma->vm_end - sa; 1239 len = (len < length) ? len : length; 1240 if (offset < len) { 1241 struct page *page = nth_page(rsv_schp->pages[k], 1242 offset >> PAGE_SHIFT); 1243 get_page(page); /* increment page count */ 1244 vmf->page = page; 1245 return 0; /* success */ 1246 } 1247 sa += len; 1248 offset -= len; 1249 } 1250 1251 return VM_FAULT_SIGBUS; 1252 } 1253 1254 static const struct vm_operations_struct sg_mmap_vm_ops = { 1255 .fault = sg_vma_fault, 1256 }; 1257 1258 static int 1259 sg_mmap(struct file *filp, struct vm_area_struct *vma) 1260 { 1261 Sg_fd *sfp; 1262 unsigned long req_sz, len, sa; 1263 Sg_scatter_hold *rsv_schp; 1264 int k, length; 1265 int ret = 0; 1266 1267 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data))) 1268 return -ENXIO; 1269 req_sz = vma->vm_end - vma->vm_start; 1270 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp, 1271 "sg_mmap starting, vm_start=%p, len=%d\n", 1272 (void *) vma->vm_start, (int) req_sz)); 1273 if (vma->vm_pgoff) 1274 return -EINVAL; /* want no offset */ 1275 rsv_schp = &sfp->reserve; 1276 mutex_lock(&sfp->f_mutex); 1277 if (req_sz > rsv_schp->bufflen) { 1278 ret = -ENOMEM; /* cannot map more than reserved buffer */ 1279 goto out; 1280 } 1281 1282 sa = vma->vm_start; 1283 length = 1 << (PAGE_SHIFT + rsv_schp->page_order); 1284 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) { 1285 len = vma->vm_end - sa; 1286 len = (len < length) ? len : length; 1287 sa += len; 1288 } 1289 1290 sfp->mmap_called = 1; 1291 vm_flags_set(vma, VM_IO | VM_DONTEXPAND | VM_DONTDUMP); 1292 vma->vm_private_data = sfp; 1293 vma->vm_ops = &sg_mmap_vm_ops; 1294 out: 1295 mutex_unlock(&sfp->f_mutex); 1296 return ret; 1297 } 1298 1299 static void 1300 sg_rq_end_io_usercontext(struct work_struct *work) 1301 { 1302 struct sg_request *srp = container_of(work, struct sg_request, ew.work); 1303 struct sg_fd *sfp = srp->parentfp; 1304 1305 sg_finish_rem_req(srp); 1306 sg_remove_request(sfp, srp); 1307 kref_put(&sfp->f_ref, sg_remove_sfp); 1308 } 1309 1310 /* 1311 * This function is a "bottom half" handler that is called by the mid 1312 * level when a command is completed (or has failed). 1313 */ 1314 static enum rq_end_io_ret 1315 sg_rq_end_io(struct request *rq, blk_status_t status) 1316 { 1317 struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(rq); 1318 struct sg_request *srp = rq->end_io_data; 1319 Sg_device *sdp; 1320 Sg_fd *sfp; 1321 unsigned long iflags; 1322 unsigned int ms; 1323 char *sense; 1324 int result, resid, done = 1; 1325 1326 if (WARN_ON(srp->done != 0)) 1327 return RQ_END_IO_NONE; 1328 1329 sfp = srp->parentfp; 1330 if (WARN_ON(sfp == NULL)) 1331 return RQ_END_IO_NONE; 1332 1333 sdp = sfp->parentdp; 1334 if (unlikely(atomic_read(&sdp->detaching))) 1335 pr_info("%s: device detaching\n", __func__); 1336 1337 sense = scmd->sense_buffer; 1338 result = scmd->result; 1339 resid = scmd->resid_len; 1340 1341 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp, 1342 "sg_cmd_done: pack_id=%d, res=0x%x\n", 1343 srp->header.pack_id, result)); 1344 srp->header.resid = resid; 1345 ms = jiffies_to_msecs(jiffies); 1346 srp->header.duration = (ms > srp->header.duration) ? 1347 (ms - srp->header.duration) : 0; 1348 if (0 != result) { 1349 struct scsi_sense_hdr sshdr; 1350 1351 srp->header.status = 0xff & result; 1352 srp->header.masked_status = sg_status_byte(result); 1353 srp->header.msg_status = COMMAND_COMPLETE; 1354 srp->header.host_status = host_byte(result); 1355 srp->header.driver_status = driver_byte(result); 1356 if ((sdp->sgdebug > 0) && 1357 ((CHECK_CONDITION == srp->header.masked_status) || 1358 (COMMAND_TERMINATED == srp->header.masked_status))) 1359 __scsi_print_sense(sdp->device, __func__, sense, 1360 SCSI_SENSE_BUFFERSIZE); 1361 1362 /* Following if statement is a patch supplied by Eric Youngdale */ 1363 if (driver_byte(result) != 0 1364 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr) 1365 && !scsi_sense_is_deferred(&sshdr) 1366 && sshdr.sense_key == UNIT_ATTENTION 1367 && sdp->device->removable) { 1368 /* Detected possible disc change. Set the bit - this */ 1369 /* may be used if there are filesystems using this device */ 1370 sdp->device->changed = 1; 1371 } 1372 } 1373 1374 if (scmd->sense_len) 1375 memcpy(srp->sense_b, scmd->sense_buffer, SCSI_SENSE_BUFFERSIZE); 1376 1377 /* Rely on write phase to clean out srp status values, so no "else" */ 1378 1379 /* 1380 * Free the request as soon as it is complete so that its resources 1381 * can be reused without waiting for userspace to read() the 1382 * result. But keep the associated bio (if any) around until 1383 * blk_rq_unmap_user() can be called from user context. 1384 */ 1385 srp->rq = NULL; 1386 blk_mq_free_request(rq); 1387 1388 write_lock_irqsave(&sfp->rq_list_lock, iflags); 1389 if (unlikely(srp->orphan)) { 1390 if (sfp->keep_orphan) 1391 srp->sg_io_owned = 0; 1392 else 1393 done = 0; 1394 } 1395 srp->done = done; 1396 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1397 1398 if (likely(done)) { 1399 /* Now wake up any sg_read() that is waiting for this 1400 * packet. 1401 */ 1402 wake_up_interruptible(&sfp->read_wait); 1403 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN); 1404 kref_put(&sfp->f_ref, sg_remove_sfp); 1405 } else { 1406 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext); 1407 schedule_work(&srp->ew.work); 1408 } 1409 return RQ_END_IO_NONE; 1410 } 1411 1412 static const struct file_operations sg_fops = { 1413 .owner = THIS_MODULE, 1414 .read = sg_read, 1415 .write = sg_write, 1416 .poll = sg_poll, 1417 .unlocked_ioctl = sg_ioctl, 1418 .compat_ioctl = compat_ptr_ioctl, 1419 .open = sg_open, 1420 .mmap = sg_mmap, 1421 .release = sg_release, 1422 .fasync = sg_fasync, 1423 .llseek = no_llseek, 1424 }; 1425 1426 static struct class *sg_sysfs_class; 1427 1428 static int sg_sysfs_valid = 0; 1429 1430 static Sg_device * 1431 sg_alloc(struct scsi_device *scsidp) 1432 { 1433 struct request_queue *q = scsidp->request_queue; 1434 Sg_device *sdp; 1435 unsigned long iflags; 1436 int error; 1437 u32 k; 1438 1439 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL); 1440 if (!sdp) { 1441 sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device " 1442 "failure\n", __func__); 1443 return ERR_PTR(-ENOMEM); 1444 } 1445 1446 idr_preload(GFP_KERNEL); 1447 write_lock_irqsave(&sg_index_lock, iflags); 1448 1449 error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT); 1450 if (error < 0) { 1451 if (error == -ENOSPC) { 1452 sdev_printk(KERN_WARNING, scsidp, 1453 "Unable to attach sg device type=%d, minor number exceeds %d\n", 1454 scsidp->type, SG_MAX_DEVS - 1); 1455 error = -ENODEV; 1456 } else { 1457 sdev_printk(KERN_WARNING, scsidp, "%s: idr " 1458 "allocation Sg_device failure: %d\n", 1459 __func__, error); 1460 } 1461 goto out_unlock; 1462 } 1463 k = error; 1464 1465 SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp, 1466 "sg_alloc: dev=%d \n", k)); 1467 sprintf(sdp->name, "sg%d", k); 1468 sdp->device = scsidp; 1469 mutex_init(&sdp->open_rel_lock); 1470 INIT_LIST_HEAD(&sdp->sfds); 1471 init_waitqueue_head(&sdp->open_wait); 1472 atomic_set(&sdp->detaching, 0); 1473 rwlock_init(&sdp->sfd_lock); 1474 sdp->sg_tablesize = queue_max_segments(q); 1475 sdp->index = k; 1476 kref_init(&sdp->d_ref); 1477 error = 0; 1478 1479 out_unlock: 1480 write_unlock_irqrestore(&sg_index_lock, iflags); 1481 idr_preload_end(); 1482 1483 if (error) { 1484 kfree(sdp); 1485 return ERR_PTR(error); 1486 } 1487 return sdp; 1488 } 1489 1490 static int 1491 sg_add_device(struct device *cl_dev) 1492 { 1493 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent); 1494 Sg_device *sdp = NULL; 1495 struct cdev * cdev = NULL; 1496 int error; 1497 unsigned long iflags; 1498 1499 error = -ENOMEM; 1500 cdev = cdev_alloc(); 1501 if (!cdev) { 1502 pr_warn("%s: cdev_alloc failed\n", __func__); 1503 goto out; 1504 } 1505 cdev->owner = THIS_MODULE; 1506 cdev->ops = &sg_fops; 1507 1508 sdp = sg_alloc(scsidp); 1509 if (IS_ERR(sdp)) { 1510 pr_warn("%s: sg_alloc failed\n", __func__); 1511 error = PTR_ERR(sdp); 1512 goto out; 1513 } 1514 1515 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1); 1516 if (error) 1517 goto cdev_add_err; 1518 1519 sdp->cdev = cdev; 1520 if (sg_sysfs_valid) { 1521 struct device *sg_class_member; 1522 1523 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent, 1524 MKDEV(SCSI_GENERIC_MAJOR, 1525 sdp->index), 1526 sdp, "%s", sdp->name); 1527 if (IS_ERR(sg_class_member)) { 1528 pr_err("%s: device_create failed\n", __func__); 1529 error = PTR_ERR(sg_class_member); 1530 goto cdev_add_err; 1531 } 1532 error = sysfs_create_link(&scsidp->sdev_gendev.kobj, 1533 &sg_class_member->kobj, "generic"); 1534 if (error) 1535 pr_err("%s: unable to make symlink 'generic' back " 1536 "to sg%d\n", __func__, sdp->index); 1537 } else 1538 pr_warn("%s: sg_sys Invalid\n", __func__); 1539 1540 sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d " 1541 "type %d\n", sdp->index, scsidp->type); 1542 1543 dev_set_drvdata(cl_dev, sdp); 1544 1545 return 0; 1546 1547 cdev_add_err: 1548 write_lock_irqsave(&sg_index_lock, iflags); 1549 idr_remove(&sg_index_idr, sdp->index); 1550 write_unlock_irqrestore(&sg_index_lock, iflags); 1551 kfree(sdp); 1552 1553 out: 1554 if (cdev) 1555 cdev_del(cdev); 1556 return error; 1557 } 1558 1559 static void 1560 sg_device_destroy(struct kref *kref) 1561 { 1562 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref); 1563 unsigned long flags; 1564 1565 /* CAUTION! Note that the device can still be found via idr_find() 1566 * even though the refcount is 0. Therefore, do idr_remove() BEFORE 1567 * any other cleanup. 1568 */ 1569 1570 write_lock_irqsave(&sg_index_lock, flags); 1571 idr_remove(&sg_index_idr, sdp->index); 1572 write_unlock_irqrestore(&sg_index_lock, flags); 1573 1574 SCSI_LOG_TIMEOUT(3, 1575 sg_printk(KERN_INFO, sdp, "sg_device_destroy\n")); 1576 1577 kfree(sdp); 1578 } 1579 1580 static void 1581 sg_remove_device(struct device *cl_dev) 1582 { 1583 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent); 1584 Sg_device *sdp = dev_get_drvdata(cl_dev); 1585 unsigned long iflags; 1586 Sg_fd *sfp; 1587 int val; 1588 1589 if (!sdp) 1590 return; 1591 /* want sdp->detaching non-zero as soon as possible */ 1592 val = atomic_inc_return(&sdp->detaching); 1593 if (val > 1) 1594 return; /* only want to do following once per device */ 1595 1596 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 1597 "%s\n", __func__)); 1598 1599 read_lock_irqsave(&sdp->sfd_lock, iflags); 1600 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) { 1601 wake_up_interruptible_all(&sfp->read_wait); 1602 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP); 1603 } 1604 wake_up_interruptible_all(&sdp->open_wait); 1605 read_unlock_irqrestore(&sdp->sfd_lock, iflags); 1606 1607 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic"); 1608 device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index)); 1609 cdev_del(sdp->cdev); 1610 sdp->cdev = NULL; 1611 1612 kref_put(&sdp->d_ref, sg_device_destroy); 1613 } 1614 1615 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR); 1616 module_param_named(def_reserved_size, def_reserved_size, int, 1617 S_IRUGO | S_IWUSR); 1618 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR); 1619 1620 MODULE_AUTHOR("Douglas Gilbert"); 1621 MODULE_DESCRIPTION("SCSI generic (sg) driver"); 1622 MODULE_LICENSE("GPL"); 1623 MODULE_VERSION(SG_VERSION_STR); 1624 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR); 1625 1626 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element " 1627 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))"); 1628 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd"); 1629 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))"); 1630 1631 #ifdef CONFIG_SYSCTL 1632 #include <linux/sysctl.h> 1633 1634 static struct ctl_table sg_sysctls[] = { 1635 { 1636 .procname = "sg-big-buff", 1637 .data = &sg_big_buff, 1638 .maxlen = sizeof(int), 1639 .mode = 0444, 1640 .proc_handler = proc_dointvec, 1641 }, 1642 {} 1643 }; 1644 1645 static struct ctl_table_header *hdr; 1646 static void register_sg_sysctls(void) 1647 { 1648 if (!hdr) 1649 hdr = register_sysctl("kernel", sg_sysctls); 1650 } 1651 1652 static void unregister_sg_sysctls(void) 1653 { 1654 if (hdr) 1655 unregister_sysctl_table(hdr); 1656 } 1657 #else 1658 #define register_sg_sysctls() do { } while (0) 1659 #define unregister_sg_sysctls() do { } while (0) 1660 #endif /* CONFIG_SYSCTL */ 1661 1662 static int __init 1663 init_sg(void) 1664 { 1665 int rc; 1666 1667 if (scatter_elem_sz < PAGE_SIZE) { 1668 scatter_elem_sz = PAGE_SIZE; 1669 scatter_elem_sz_prev = scatter_elem_sz; 1670 } 1671 if (def_reserved_size >= 0) 1672 sg_big_buff = def_reserved_size; 1673 else 1674 def_reserved_size = sg_big_buff; 1675 1676 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), 1677 SG_MAX_DEVS, "sg"); 1678 if (rc) 1679 return rc; 1680 sg_sysfs_class = class_create("scsi_generic"); 1681 if ( IS_ERR(sg_sysfs_class) ) { 1682 rc = PTR_ERR(sg_sysfs_class); 1683 goto err_out; 1684 } 1685 sg_sysfs_valid = 1; 1686 rc = scsi_register_interface(&sg_interface); 1687 if (0 == rc) { 1688 #ifdef CONFIG_SCSI_PROC_FS 1689 sg_proc_init(); 1690 #endif /* CONFIG_SCSI_PROC_FS */ 1691 return 0; 1692 } 1693 class_destroy(sg_sysfs_class); 1694 register_sg_sysctls(); 1695 err_out: 1696 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS); 1697 return rc; 1698 } 1699 1700 static void __exit 1701 exit_sg(void) 1702 { 1703 unregister_sg_sysctls(); 1704 #ifdef CONFIG_SCSI_PROC_FS 1705 remove_proc_subtree("scsi/sg", NULL); 1706 #endif /* CONFIG_SCSI_PROC_FS */ 1707 scsi_unregister_interface(&sg_interface); 1708 class_destroy(sg_sysfs_class); 1709 sg_sysfs_valid = 0; 1710 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), 1711 SG_MAX_DEVS); 1712 idr_destroy(&sg_index_idr); 1713 } 1714 1715 static int 1716 sg_start_req(Sg_request *srp, unsigned char *cmd) 1717 { 1718 int res; 1719 struct request *rq; 1720 Sg_fd *sfp = srp->parentfp; 1721 sg_io_hdr_t *hp = &srp->header; 1722 int dxfer_len = (int) hp->dxfer_len; 1723 int dxfer_dir = hp->dxfer_direction; 1724 unsigned int iov_count = hp->iovec_count; 1725 Sg_scatter_hold *req_schp = &srp->data; 1726 Sg_scatter_hold *rsv_schp = &sfp->reserve; 1727 struct request_queue *q = sfp->parentdp->device->request_queue; 1728 struct rq_map_data *md, map_data; 1729 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? ITER_SOURCE : ITER_DEST; 1730 struct scsi_cmnd *scmd; 1731 1732 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 1733 "sg_start_req: dxfer_len=%d\n", 1734 dxfer_len)); 1735 1736 /* 1737 * NOTE 1738 * 1739 * With scsi-mq enabled, there are a fixed number of preallocated 1740 * requests equal in number to shost->can_queue. If all of the 1741 * preallocated requests are already in use, then scsi_alloc_request() 1742 * will sleep until an active command completes, freeing up a request. 1743 * Although waiting in an asynchronous interface is less than ideal, we 1744 * do not want to use BLK_MQ_REQ_NOWAIT here because userspace might 1745 * not expect an EWOULDBLOCK from this condition. 1746 */ 1747 rq = scsi_alloc_request(q, hp->dxfer_direction == SG_DXFER_TO_DEV ? 1748 REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0); 1749 if (IS_ERR(rq)) 1750 return PTR_ERR(rq); 1751 scmd = blk_mq_rq_to_pdu(rq); 1752 1753 if (hp->cmd_len > sizeof(scmd->cmnd)) { 1754 blk_mq_free_request(rq); 1755 return -EINVAL; 1756 } 1757 1758 memcpy(scmd->cmnd, cmd, hp->cmd_len); 1759 scmd->cmd_len = hp->cmd_len; 1760 1761 srp->rq = rq; 1762 rq->end_io_data = srp; 1763 scmd->allowed = SG_DEFAULT_RETRIES; 1764 1765 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE)) 1766 return 0; 1767 1768 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO && 1769 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count && 1770 blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len)) 1771 md = NULL; 1772 else 1773 md = &map_data; 1774 1775 if (md) { 1776 mutex_lock(&sfp->f_mutex); 1777 if (dxfer_len <= rsv_schp->bufflen && 1778 !sfp->res_in_use) { 1779 sfp->res_in_use = 1; 1780 sg_link_reserve(sfp, srp, dxfer_len); 1781 } else if (hp->flags & SG_FLAG_MMAP_IO) { 1782 res = -EBUSY; /* sfp->res_in_use == 1 */ 1783 if (dxfer_len > rsv_schp->bufflen) 1784 res = -ENOMEM; 1785 mutex_unlock(&sfp->f_mutex); 1786 return res; 1787 } else { 1788 res = sg_build_indirect(req_schp, sfp, dxfer_len); 1789 if (res) { 1790 mutex_unlock(&sfp->f_mutex); 1791 return res; 1792 } 1793 } 1794 mutex_unlock(&sfp->f_mutex); 1795 1796 md->pages = req_schp->pages; 1797 md->page_order = req_schp->page_order; 1798 md->nr_entries = req_schp->k_use_sg; 1799 md->offset = 0; 1800 md->null_mapped = hp->dxferp ? 0 : 1; 1801 if (dxfer_dir == SG_DXFER_TO_FROM_DEV) 1802 md->from_user = 1; 1803 else 1804 md->from_user = 0; 1805 } 1806 1807 res = blk_rq_map_user_io(rq, md, hp->dxferp, hp->dxfer_len, 1808 GFP_ATOMIC, iov_count, iov_count, 1, rw); 1809 if (!res) { 1810 srp->bio = rq->bio; 1811 1812 if (!md) { 1813 req_schp->dio_in_use = 1; 1814 hp->info |= SG_INFO_DIRECT_IO; 1815 } 1816 } 1817 return res; 1818 } 1819 1820 static int 1821 sg_finish_rem_req(Sg_request *srp) 1822 { 1823 int ret = 0; 1824 1825 Sg_fd *sfp = srp->parentfp; 1826 Sg_scatter_hold *req_schp = &srp->data; 1827 1828 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 1829 "sg_finish_rem_req: res_used=%d\n", 1830 (int) srp->res_used)); 1831 if (srp->bio) 1832 ret = blk_rq_unmap_user(srp->bio); 1833 1834 if (srp->rq) 1835 blk_mq_free_request(srp->rq); 1836 1837 if (srp->res_used) 1838 sg_unlink_reserve(sfp, srp); 1839 else 1840 sg_remove_scat(sfp, req_schp); 1841 1842 return ret; 1843 } 1844 1845 static int 1846 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize) 1847 { 1848 int sg_bufflen = tablesize * sizeof(struct page *); 1849 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN; 1850 1851 schp->pages = kzalloc(sg_bufflen, gfp_flags); 1852 if (!schp->pages) 1853 return -ENOMEM; 1854 schp->sglist_len = sg_bufflen; 1855 return tablesize; /* number of scat_gath elements allocated */ 1856 } 1857 1858 static int 1859 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size) 1860 { 1861 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems; 1862 int sg_tablesize = sfp->parentdp->sg_tablesize; 1863 int blk_size = buff_size, order; 1864 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN | __GFP_ZERO; 1865 1866 if (blk_size < 0) 1867 return -EFAULT; 1868 if (0 == blk_size) 1869 ++blk_size; /* don't know why */ 1870 /* round request up to next highest SG_SECTOR_SZ byte boundary */ 1871 blk_size = ALIGN(blk_size, SG_SECTOR_SZ); 1872 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 1873 "sg_build_indirect: buff_size=%d, blk_size=%d\n", 1874 buff_size, blk_size)); 1875 1876 /* N.B. ret_sz carried into this block ... */ 1877 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize); 1878 if (mx_sc_elems < 0) 1879 return mx_sc_elems; /* most likely -ENOMEM */ 1880 1881 num = scatter_elem_sz; 1882 if (unlikely(num != scatter_elem_sz_prev)) { 1883 if (num < PAGE_SIZE) { 1884 scatter_elem_sz = PAGE_SIZE; 1885 scatter_elem_sz_prev = PAGE_SIZE; 1886 } else 1887 scatter_elem_sz_prev = num; 1888 } 1889 1890 order = get_order(num); 1891 retry: 1892 ret_sz = 1 << (PAGE_SHIFT + order); 1893 1894 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems; 1895 k++, rem_sz -= ret_sz) { 1896 1897 num = (rem_sz > scatter_elem_sz_prev) ? 1898 scatter_elem_sz_prev : rem_sz; 1899 1900 schp->pages[k] = alloc_pages(gfp_mask, order); 1901 if (!schp->pages[k]) 1902 goto out; 1903 1904 if (num == scatter_elem_sz_prev) { 1905 if (unlikely(ret_sz > scatter_elem_sz_prev)) { 1906 scatter_elem_sz = ret_sz; 1907 scatter_elem_sz_prev = ret_sz; 1908 } 1909 } 1910 1911 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp, 1912 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n", 1913 k, num, ret_sz)); 1914 } /* end of for loop */ 1915 1916 schp->page_order = order; 1917 schp->k_use_sg = k; 1918 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp, 1919 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n", 1920 k, rem_sz)); 1921 1922 schp->bufflen = blk_size; 1923 if (rem_sz > 0) /* must have failed */ 1924 return -ENOMEM; 1925 return 0; 1926 out: 1927 for (i = 0; i < k; i++) 1928 __free_pages(schp->pages[i], order); 1929 1930 if (--order >= 0) 1931 goto retry; 1932 1933 return -ENOMEM; 1934 } 1935 1936 static void 1937 sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp) 1938 { 1939 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 1940 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg)); 1941 if (schp->pages && schp->sglist_len > 0) { 1942 if (!schp->dio_in_use) { 1943 int k; 1944 1945 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) { 1946 SCSI_LOG_TIMEOUT(5, 1947 sg_printk(KERN_INFO, sfp->parentdp, 1948 "sg_remove_scat: k=%d, pg=0x%p\n", 1949 k, schp->pages[k])); 1950 __free_pages(schp->pages[k], schp->page_order); 1951 } 1952 1953 kfree(schp->pages); 1954 } 1955 } 1956 memset(schp, 0, sizeof (*schp)); 1957 } 1958 1959 static int 1960 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer) 1961 { 1962 Sg_scatter_hold *schp = &srp->data; 1963 int k, num; 1964 1965 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp, 1966 "sg_read_oxfer: num_read_xfer=%d\n", 1967 num_read_xfer)); 1968 if ((!outp) || (num_read_xfer <= 0)) 1969 return 0; 1970 1971 num = 1 << (PAGE_SHIFT + schp->page_order); 1972 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) { 1973 if (num > num_read_xfer) { 1974 if (copy_to_user(outp, page_address(schp->pages[k]), 1975 num_read_xfer)) 1976 return -EFAULT; 1977 break; 1978 } else { 1979 if (copy_to_user(outp, page_address(schp->pages[k]), 1980 num)) 1981 return -EFAULT; 1982 num_read_xfer -= num; 1983 if (num_read_xfer <= 0) 1984 break; 1985 outp += num; 1986 } 1987 } 1988 1989 return 0; 1990 } 1991 1992 static void 1993 sg_build_reserve(Sg_fd * sfp, int req_size) 1994 { 1995 Sg_scatter_hold *schp = &sfp->reserve; 1996 1997 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 1998 "sg_build_reserve: req_size=%d\n", req_size)); 1999 do { 2000 if (req_size < PAGE_SIZE) 2001 req_size = PAGE_SIZE; 2002 if (0 == sg_build_indirect(schp, sfp, req_size)) 2003 return; 2004 else 2005 sg_remove_scat(sfp, schp); 2006 req_size >>= 1; /* divide by 2 */ 2007 } while (req_size > (PAGE_SIZE / 2)); 2008 } 2009 2010 static void 2011 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size) 2012 { 2013 Sg_scatter_hold *req_schp = &srp->data; 2014 Sg_scatter_hold *rsv_schp = &sfp->reserve; 2015 int k, num, rem; 2016 2017 srp->res_used = 1; 2018 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 2019 "sg_link_reserve: size=%d\n", size)); 2020 rem = size; 2021 2022 num = 1 << (PAGE_SHIFT + rsv_schp->page_order); 2023 for (k = 0; k < rsv_schp->k_use_sg; k++) { 2024 if (rem <= num) { 2025 req_schp->k_use_sg = k + 1; 2026 req_schp->sglist_len = rsv_schp->sglist_len; 2027 req_schp->pages = rsv_schp->pages; 2028 2029 req_schp->bufflen = size; 2030 req_schp->page_order = rsv_schp->page_order; 2031 break; 2032 } else 2033 rem -= num; 2034 } 2035 2036 if (k >= rsv_schp->k_use_sg) 2037 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp, 2038 "sg_link_reserve: BAD size\n")); 2039 } 2040 2041 static void 2042 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp) 2043 { 2044 Sg_scatter_hold *req_schp = &srp->data; 2045 2046 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp, 2047 "sg_unlink_reserve: req->k_use_sg=%d\n", 2048 (int) req_schp->k_use_sg)); 2049 req_schp->k_use_sg = 0; 2050 req_schp->bufflen = 0; 2051 req_schp->pages = NULL; 2052 req_schp->page_order = 0; 2053 req_schp->sglist_len = 0; 2054 srp->res_used = 0; 2055 /* Called without mutex lock to avoid deadlock */ 2056 sfp->res_in_use = 0; 2057 } 2058 2059 static Sg_request * 2060 sg_get_rq_mark(Sg_fd * sfp, int pack_id, bool *busy) 2061 { 2062 Sg_request *resp; 2063 unsigned long iflags; 2064 2065 *busy = false; 2066 write_lock_irqsave(&sfp->rq_list_lock, iflags); 2067 list_for_each_entry(resp, &sfp->rq_list, entry) { 2068 /* look for requests that are not SG_IO owned */ 2069 if ((!resp->sg_io_owned) && 2070 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) { 2071 switch (resp->done) { 2072 case 0: /* request active */ 2073 *busy = true; 2074 break; 2075 case 1: /* request done; response ready to return */ 2076 resp->done = 2; /* guard against other readers */ 2077 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2078 return resp; 2079 case 2: /* response already being returned */ 2080 break; 2081 } 2082 } 2083 } 2084 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2085 return NULL; 2086 } 2087 2088 /* always adds to end of list */ 2089 static Sg_request * 2090 sg_add_request(Sg_fd * sfp) 2091 { 2092 int k; 2093 unsigned long iflags; 2094 Sg_request *rp = sfp->req_arr; 2095 2096 write_lock_irqsave(&sfp->rq_list_lock, iflags); 2097 if (!list_empty(&sfp->rq_list)) { 2098 if (!sfp->cmd_q) 2099 goto out_unlock; 2100 2101 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) { 2102 if (!rp->parentfp) 2103 break; 2104 } 2105 if (k >= SG_MAX_QUEUE) 2106 goto out_unlock; 2107 } 2108 memset(rp, 0, sizeof (Sg_request)); 2109 rp->parentfp = sfp; 2110 rp->header.duration = jiffies_to_msecs(jiffies); 2111 list_add_tail(&rp->entry, &sfp->rq_list); 2112 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2113 return rp; 2114 out_unlock: 2115 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2116 return NULL; 2117 } 2118 2119 /* Return of 1 for found; 0 for not found */ 2120 static int 2121 sg_remove_request(Sg_fd * sfp, Sg_request * srp) 2122 { 2123 unsigned long iflags; 2124 int res = 0; 2125 2126 if (!sfp || !srp || list_empty(&sfp->rq_list)) 2127 return res; 2128 write_lock_irqsave(&sfp->rq_list_lock, iflags); 2129 if (!list_empty(&srp->entry)) { 2130 list_del(&srp->entry); 2131 srp->parentfp = NULL; 2132 res = 1; 2133 } 2134 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2135 2136 /* 2137 * If the device is detaching, wakeup any readers in case we just 2138 * removed the last response, which would leave nothing for them to 2139 * return other than -ENODEV. 2140 */ 2141 if (unlikely(atomic_read(&sfp->parentdp->detaching))) 2142 wake_up_interruptible_all(&sfp->read_wait); 2143 2144 return res; 2145 } 2146 2147 static Sg_fd * 2148 sg_add_sfp(Sg_device * sdp) 2149 { 2150 Sg_fd *sfp; 2151 unsigned long iflags; 2152 int bufflen; 2153 2154 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN); 2155 if (!sfp) 2156 return ERR_PTR(-ENOMEM); 2157 2158 init_waitqueue_head(&sfp->read_wait); 2159 rwlock_init(&sfp->rq_list_lock); 2160 INIT_LIST_HEAD(&sfp->rq_list); 2161 kref_init(&sfp->f_ref); 2162 mutex_init(&sfp->f_mutex); 2163 sfp->timeout = SG_DEFAULT_TIMEOUT; 2164 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER; 2165 sfp->force_packid = SG_DEF_FORCE_PACK_ID; 2166 sfp->cmd_q = SG_DEF_COMMAND_Q; 2167 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN; 2168 sfp->parentdp = sdp; 2169 write_lock_irqsave(&sdp->sfd_lock, iflags); 2170 if (atomic_read(&sdp->detaching)) { 2171 write_unlock_irqrestore(&sdp->sfd_lock, iflags); 2172 kfree(sfp); 2173 return ERR_PTR(-ENODEV); 2174 } 2175 list_add_tail(&sfp->sfd_siblings, &sdp->sfds); 2176 write_unlock_irqrestore(&sdp->sfd_lock, iflags); 2177 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 2178 "sg_add_sfp: sfp=0x%p\n", sfp)); 2179 if (unlikely(sg_big_buff != def_reserved_size)) 2180 sg_big_buff = def_reserved_size; 2181 2182 bufflen = min_t(int, sg_big_buff, 2183 max_sectors_bytes(sdp->device->request_queue)); 2184 sg_build_reserve(sfp, bufflen); 2185 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 2186 "sg_add_sfp: bufflen=%d, k_use_sg=%d\n", 2187 sfp->reserve.bufflen, 2188 sfp->reserve.k_use_sg)); 2189 2190 kref_get(&sdp->d_ref); 2191 __module_get(THIS_MODULE); 2192 return sfp; 2193 } 2194 2195 static void 2196 sg_remove_sfp_usercontext(struct work_struct *work) 2197 { 2198 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work); 2199 struct sg_device *sdp = sfp->parentdp; 2200 Sg_request *srp; 2201 unsigned long iflags; 2202 2203 /* Cleanup any responses which were never read(). */ 2204 write_lock_irqsave(&sfp->rq_list_lock, iflags); 2205 while (!list_empty(&sfp->rq_list)) { 2206 srp = list_first_entry(&sfp->rq_list, Sg_request, entry); 2207 sg_finish_rem_req(srp); 2208 list_del(&srp->entry); 2209 srp->parentfp = NULL; 2210 } 2211 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2212 2213 if (sfp->reserve.bufflen > 0) { 2214 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp, 2215 "sg_remove_sfp: bufflen=%d, k_use_sg=%d\n", 2216 (int) sfp->reserve.bufflen, 2217 (int) sfp->reserve.k_use_sg)); 2218 sg_remove_scat(sfp, &sfp->reserve); 2219 } 2220 2221 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp, 2222 "sg_remove_sfp: sfp=0x%p\n", sfp)); 2223 kfree(sfp); 2224 2225 scsi_device_put(sdp->device); 2226 kref_put(&sdp->d_ref, sg_device_destroy); 2227 module_put(THIS_MODULE); 2228 } 2229 2230 static void 2231 sg_remove_sfp(struct kref *kref) 2232 { 2233 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref); 2234 struct sg_device *sdp = sfp->parentdp; 2235 unsigned long iflags; 2236 2237 write_lock_irqsave(&sdp->sfd_lock, iflags); 2238 list_del(&sfp->sfd_siblings); 2239 write_unlock_irqrestore(&sdp->sfd_lock, iflags); 2240 2241 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext); 2242 schedule_work(&sfp->ew.work); 2243 } 2244 2245 #ifdef CONFIG_SCSI_PROC_FS 2246 static int 2247 sg_idr_max_id(int id, void *p, void *data) 2248 { 2249 int *k = data; 2250 2251 if (*k < id) 2252 *k = id; 2253 2254 return 0; 2255 } 2256 2257 static int 2258 sg_last_dev(void) 2259 { 2260 int k = -1; 2261 unsigned long iflags; 2262 2263 read_lock_irqsave(&sg_index_lock, iflags); 2264 idr_for_each(&sg_index_idr, sg_idr_max_id, &k); 2265 read_unlock_irqrestore(&sg_index_lock, iflags); 2266 return k + 1; /* origin 1 */ 2267 } 2268 #endif 2269 2270 /* must be called with sg_index_lock held */ 2271 static Sg_device *sg_lookup_dev(int dev) 2272 { 2273 return idr_find(&sg_index_idr, dev); 2274 } 2275 2276 static Sg_device * 2277 sg_get_dev(int dev) 2278 { 2279 struct sg_device *sdp; 2280 unsigned long flags; 2281 2282 read_lock_irqsave(&sg_index_lock, flags); 2283 sdp = sg_lookup_dev(dev); 2284 if (!sdp) 2285 sdp = ERR_PTR(-ENXIO); 2286 else if (atomic_read(&sdp->detaching)) { 2287 /* If sdp->detaching, then the refcount may already be 0, in 2288 * which case it would be a bug to do kref_get(). 2289 */ 2290 sdp = ERR_PTR(-ENODEV); 2291 } else 2292 kref_get(&sdp->d_ref); 2293 read_unlock_irqrestore(&sg_index_lock, flags); 2294 2295 return sdp; 2296 } 2297 2298 #ifdef CONFIG_SCSI_PROC_FS 2299 static int sg_proc_seq_show_int(struct seq_file *s, void *v); 2300 2301 static int sg_proc_single_open_adio(struct inode *inode, struct file *file); 2302 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer, 2303 size_t count, loff_t *off); 2304 static const struct proc_ops adio_proc_ops = { 2305 .proc_open = sg_proc_single_open_adio, 2306 .proc_read = seq_read, 2307 .proc_lseek = seq_lseek, 2308 .proc_write = sg_proc_write_adio, 2309 .proc_release = single_release, 2310 }; 2311 2312 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file); 2313 static ssize_t sg_proc_write_dressz(struct file *filp, 2314 const char __user *buffer, size_t count, loff_t *off); 2315 static const struct proc_ops dressz_proc_ops = { 2316 .proc_open = sg_proc_single_open_dressz, 2317 .proc_read = seq_read, 2318 .proc_lseek = seq_lseek, 2319 .proc_write = sg_proc_write_dressz, 2320 .proc_release = single_release, 2321 }; 2322 2323 static int sg_proc_seq_show_version(struct seq_file *s, void *v); 2324 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v); 2325 static int sg_proc_seq_show_dev(struct seq_file *s, void *v); 2326 static void * dev_seq_start(struct seq_file *s, loff_t *pos); 2327 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos); 2328 static void dev_seq_stop(struct seq_file *s, void *v); 2329 static const struct seq_operations dev_seq_ops = { 2330 .start = dev_seq_start, 2331 .next = dev_seq_next, 2332 .stop = dev_seq_stop, 2333 .show = sg_proc_seq_show_dev, 2334 }; 2335 2336 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v); 2337 static const struct seq_operations devstrs_seq_ops = { 2338 .start = dev_seq_start, 2339 .next = dev_seq_next, 2340 .stop = dev_seq_stop, 2341 .show = sg_proc_seq_show_devstrs, 2342 }; 2343 2344 static int sg_proc_seq_show_debug(struct seq_file *s, void *v); 2345 static const struct seq_operations debug_seq_ops = { 2346 .start = dev_seq_start, 2347 .next = dev_seq_next, 2348 .stop = dev_seq_stop, 2349 .show = sg_proc_seq_show_debug, 2350 }; 2351 2352 static int 2353 sg_proc_init(void) 2354 { 2355 struct proc_dir_entry *p; 2356 2357 p = proc_mkdir("scsi/sg", NULL); 2358 if (!p) 2359 return 1; 2360 2361 proc_create("allow_dio", S_IRUGO | S_IWUSR, p, &adio_proc_ops); 2362 proc_create_seq("debug", S_IRUGO, p, &debug_seq_ops); 2363 proc_create("def_reserved_size", S_IRUGO | S_IWUSR, p, &dressz_proc_ops); 2364 proc_create_single("device_hdr", S_IRUGO, p, sg_proc_seq_show_devhdr); 2365 proc_create_seq("devices", S_IRUGO, p, &dev_seq_ops); 2366 proc_create_seq("device_strs", S_IRUGO, p, &devstrs_seq_ops); 2367 proc_create_single("version", S_IRUGO, p, sg_proc_seq_show_version); 2368 return 0; 2369 } 2370 2371 2372 static int sg_proc_seq_show_int(struct seq_file *s, void *v) 2373 { 2374 seq_printf(s, "%d\n", *((int *)s->private)); 2375 return 0; 2376 } 2377 2378 static int sg_proc_single_open_adio(struct inode *inode, struct file *file) 2379 { 2380 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio); 2381 } 2382 2383 static ssize_t 2384 sg_proc_write_adio(struct file *filp, const char __user *buffer, 2385 size_t count, loff_t *off) 2386 { 2387 int err; 2388 unsigned long num; 2389 2390 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) 2391 return -EACCES; 2392 err = kstrtoul_from_user(buffer, count, 0, &num); 2393 if (err) 2394 return err; 2395 sg_allow_dio = num ? 1 : 0; 2396 return count; 2397 } 2398 2399 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file) 2400 { 2401 return single_open(file, sg_proc_seq_show_int, &sg_big_buff); 2402 } 2403 2404 static ssize_t 2405 sg_proc_write_dressz(struct file *filp, const char __user *buffer, 2406 size_t count, loff_t *off) 2407 { 2408 int err; 2409 unsigned long k = ULONG_MAX; 2410 2411 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) 2412 return -EACCES; 2413 2414 err = kstrtoul_from_user(buffer, count, 0, &k); 2415 if (err) 2416 return err; 2417 if (k <= 1048576) { /* limit "big buff" to 1 MB */ 2418 sg_big_buff = k; 2419 return count; 2420 } 2421 return -ERANGE; 2422 } 2423 2424 static int sg_proc_seq_show_version(struct seq_file *s, void *v) 2425 { 2426 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR, 2427 sg_version_date); 2428 return 0; 2429 } 2430 2431 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v) 2432 { 2433 seq_puts(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n"); 2434 return 0; 2435 } 2436 2437 struct sg_proc_deviter { 2438 loff_t index; 2439 size_t max; 2440 }; 2441 2442 static void * dev_seq_start(struct seq_file *s, loff_t *pos) 2443 { 2444 struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL); 2445 2446 s->private = it; 2447 if (! it) 2448 return NULL; 2449 2450 it->index = *pos; 2451 it->max = sg_last_dev(); 2452 if (it->index >= it->max) 2453 return NULL; 2454 return it; 2455 } 2456 2457 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos) 2458 { 2459 struct sg_proc_deviter * it = s->private; 2460 2461 *pos = ++it->index; 2462 return (it->index < it->max) ? it : NULL; 2463 } 2464 2465 static void dev_seq_stop(struct seq_file *s, void *v) 2466 { 2467 kfree(s->private); 2468 } 2469 2470 static int sg_proc_seq_show_dev(struct seq_file *s, void *v) 2471 { 2472 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v; 2473 Sg_device *sdp; 2474 struct scsi_device *scsidp; 2475 unsigned long iflags; 2476 2477 read_lock_irqsave(&sg_index_lock, iflags); 2478 sdp = it ? sg_lookup_dev(it->index) : NULL; 2479 if ((NULL == sdp) || (NULL == sdp->device) || 2480 (atomic_read(&sdp->detaching))) 2481 seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n"); 2482 else { 2483 scsidp = sdp->device; 2484 seq_printf(s, "%d\t%d\t%d\t%llu\t%d\t%d\t%d\t%d\t%d\n", 2485 scsidp->host->host_no, scsidp->channel, 2486 scsidp->id, scsidp->lun, (int) scsidp->type, 2487 1, 2488 (int) scsidp->queue_depth, 2489 (int) scsi_device_busy(scsidp), 2490 (int) scsi_device_online(scsidp)); 2491 } 2492 read_unlock_irqrestore(&sg_index_lock, iflags); 2493 return 0; 2494 } 2495 2496 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v) 2497 { 2498 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v; 2499 Sg_device *sdp; 2500 struct scsi_device *scsidp; 2501 unsigned long iflags; 2502 2503 read_lock_irqsave(&sg_index_lock, iflags); 2504 sdp = it ? sg_lookup_dev(it->index) : NULL; 2505 scsidp = sdp ? sdp->device : NULL; 2506 if (sdp && scsidp && (!atomic_read(&sdp->detaching))) 2507 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n", 2508 scsidp->vendor, scsidp->model, scsidp->rev); 2509 else 2510 seq_puts(s, "<no active device>\n"); 2511 read_unlock_irqrestore(&sg_index_lock, iflags); 2512 return 0; 2513 } 2514 2515 /* must be called while holding sg_index_lock */ 2516 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp) 2517 { 2518 int k, new_interface, blen, usg; 2519 Sg_request *srp; 2520 Sg_fd *fp; 2521 const sg_io_hdr_t *hp; 2522 const char * cp; 2523 unsigned int ms; 2524 2525 k = 0; 2526 list_for_each_entry(fp, &sdp->sfds, sfd_siblings) { 2527 k++; 2528 read_lock(&fp->rq_list_lock); /* irqs already disabled */ 2529 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d " 2530 "(res)sgat=%d low_dma=%d\n", k, 2531 jiffies_to_msecs(fp->timeout), 2532 fp->reserve.bufflen, 2533 (int) fp->reserve.k_use_sg, 0); 2534 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n", 2535 (int) fp->cmd_q, (int) fp->force_packid, 2536 (int) fp->keep_orphan); 2537 list_for_each_entry(srp, &fp->rq_list, entry) { 2538 hp = &srp->header; 2539 new_interface = (hp->interface_id == '\0') ? 0 : 1; 2540 if (srp->res_used) { 2541 if (new_interface && 2542 (SG_FLAG_MMAP_IO & hp->flags)) 2543 cp = " mmap>> "; 2544 else 2545 cp = " rb>> "; 2546 } else { 2547 if (SG_INFO_DIRECT_IO_MASK & hp->info) 2548 cp = " dio>> "; 2549 else 2550 cp = " "; 2551 } 2552 seq_puts(s, cp); 2553 blen = srp->data.bufflen; 2554 usg = srp->data.k_use_sg; 2555 seq_puts(s, srp->done ? 2556 ((1 == srp->done) ? "rcv:" : "fin:") 2557 : "act:"); 2558 seq_printf(s, " id=%d blen=%d", 2559 srp->header.pack_id, blen); 2560 if (srp->done) 2561 seq_printf(s, " dur=%d", hp->duration); 2562 else { 2563 ms = jiffies_to_msecs(jiffies); 2564 seq_printf(s, " t_o/elap=%d/%d", 2565 (new_interface ? hp->timeout : 2566 jiffies_to_msecs(fp->timeout)), 2567 (ms > hp->duration ? ms - hp->duration : 0)); 2568 } 2569 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg, 2570 (int) srp->data.cmd_opcode); 2571 } 2572 if (list_empty(&fp->rq_list)) 2573 seq_puts(s, " No requests active\n"); 2574 read_unlock(&fp->rq_list_lock); 2575 } 2576 } 2577 2578 static int sg_proc_seq_show_debug(struct seq_file *s, void *v) 2579 { 2580 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v; 2581 Sg_device *sdp; 2582 unsigned long iflags; 2583 2584 if (it && (0 == it->index)) 2585 seq_printf(s, "max_active_device=%d def_reserved_size=%d\n", 2586 (int)it->max, sg_big_buff); 2587 2588 read_lock_irqsave(&sg_index_lock, iflags); 2589 sdp = it ? sg_lookup_dev(it->index) : NULL; 2590 if (NULL == sdp) 2591 goto skip; 2592 read_lock(&sdp->sfd_lock); 2593 if (!list_empty(&sdp->sfds)) { 2594 seq_printf(s, " >>> device=%s ", sdp->name); 2595 if (atomic_read(&sdp->detaching)) 2596 seq_puts(s, "detaching pending close "); 2597 else if (sdp->device) { 2598 struct scsi_device *scsidp = sdp->device; 2599 2600 seq_printf(s, "%d:%d:%d:%llu em=%d", 2601 scsidp->host->host_no, 2602 scsidp->channel, scsidp->id, 2603 scsidp->lun, 2604 scsidp->host->hostt->emulated); 2605 } 2606 seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n", 2607 sdp->sg_tablesize, sdp->exclude, sdp->open_cnt); 2608 sg_proc_debug_helper(s, sdp); 2609 } 2610 read_unlock(&sdp->sfd_lock); 2611 skip: 2612 read_unlock_irqrestore(&sg_index_lock, iflags); 2613 return 0; 2614 } 2615 2616 #endif /* CONFIG_SCSI_PROC_FS */ 2617 2618 module_init(init_sg); 2619 module_exit(exit_sg); 2620