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/slab.h> 35 #include <linux/fcntl.h> 36 #include <linux/init.h> 37 #include <linux/poll.h> 38 #include <linux/moduleparam.h> 39 #include <linux/cdev.h> 40 #include <linux/idr.h> 41 #include <linux/seq_file.h> 42 #include <linux/blkdev.h> 43 #include <linux/delay.h> 44 #include <linux/blktrace_api.h> 45 #include <linux/mutex.h> 46 #include <linux/atomic.h> 47 #include <linux/ratelimit.h> 48 #include <linux/uio.h> 49 #include <linux/cred.h> /* for sg_check_file_access() */ 50 51 #include "scsi.h" 52 #include <scsi/scsi_dbg.h> 53 #include <scsi/scsi_host.h> 54 #include <scsi/scsi_driver.h> 55 #include <scsi/scsi_ioctl.h> 56 #include <scsi/sg.h> 57 58 #include "scsi_logging.h" 59 60 #ifdef CONFIG_SCSI_PROC_FS 61 #include <linux/proc_fs.h> 62 static char *sg_version_date = "20140603"; 63 64 static int sg_proc_init(void); 65 #endif 66 67 #define SG_ALLOW_DIO_DEF 0 68 69 #define SG_MAX_DEVS 32768 70 71 /* SG_MAX_CDB_SIZE should be 260 (spc4r37 section 3.1.30) however the type 72 * of sg_io_hdr::cmd_len can only represent 255. All SCSI commands greater 73 * than 16 bytes are "variable length" whose length is a multiple of 4 74 */ 75 #define SG_MAX_CDB_SIZE 252 76 77 #define SG_DEFAULT_TIMEOUT mult_frac(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ) 78 79 int sg_big_buff = SG_DEF_RESERVED_SIZE; 80 /* N.B. This variable is readable and writeable via 81 /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer 82 of this size (or less if there is not enough memory) will be reserved 83 for use by this file descriptor. [Deprecated usage: this variable is also 84 readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into 85 the kernel (i.e. it is not a module).] */ 86 static int def_reserved_size = -1; /* picks up init parameter */ 87 static int sg_allow_dio = SG_ALLOW_DIO_DEF; 88 89 static int scatter_elem_sz = SG_SCATTER_SZ; 90 static int scatter_elem_sz_prev = SG_SCATTER_SZ; 91 92 #define SG_SECTOR_SZ 512 93 94 static int sg_add_device(struct device *, struct class_interface *); 95 static void sg_remove_device(struct device *, struct class_interface *); 96 97 static DEFINE_IDR(sg_index_idr); 98 static DEFINE_RWLOCK(sg_index_lock); /* Also used to lock 99 file descriptor list for device */ 100 101 static struct class_interface sg_interface = { 102 .add_dev = sg_add_device, 103 .remove_dev = sg_remove_device, 104 }; 105 106 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */ 107 unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */ 108 unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */ 109 unsigned bufflen; /* Size of (aggregate) data buffer */ 110 struct page **pages; 111 int page_order; 112 char dio_in_use; /* 0->indirect IO (or mmap), 1->dio */ 113 unsigned char cmd_opcode; /* first byte of command */ 114 } Sg_scatter_hold; 115 116 struct sg_device; /* forward declarations */ 117 struct sg_fd; 118 119 typedef struct sg_request { /* SG_MAX_QUEUE requests outstanding per file */ 120 struct list_head entry; /* list entry */ 121 struct sg_fd *parentfp; /* NULL -> not in use */ 122 Sg_scatter_hold data; /* hold buffer, perhaps scatter list */ 123 sg_io_hdr_t header; /* scsi command+info, see <scsi/sg.h> */ 124 unsigned char sense_b[SCSI_SENSE_BUFFERSIZE]; 125 char res_used; /* 1 -> using reserve buffer, 0 -> not ... */ 126 char orphan; /* 1 -> drop on sight, 0 -> normal */ 127 char sg_io_owned; /* 1 -> packet belongs to SG_IO */ 128 /* done protected by rq_list_lock */ 129 char done; /* 0->before bh, 1->before read, 2->read */ 130 struct request *rq; 131 struct bio *bio; 132 struct execute_work ew; 133 } Sg_request; 134 135 typedef struct sg_fd { /* holds the state of a file descriptor */ 136 struct list_head sfd_siblings; /* protected by device's sfd_lock */ 137 struct sg_device *parentdp; /* owning device */ 138 wait_queue_head_t read_wait; /* queue read until command done */ 139 rwlock_t rq_list_lock; /* protect access to list in req_arr */ 140 struct mutex f_mutex; /* protect against changes in this fd */ 141 int timeout; /* defaults to SG_DEFAULT_TIMEOUT */ 142 int timeout_user; /* defaults to SG_DEFAULT_TIMEOUT_USER */ 143 Sg_scatter_hold reserve; /* buffer held for this file descriptor */ 144 struct list_head rq_list; /* head of request list */ 145 struct fasync_struct *async_qp; /* used by asynchronous notification */ 146 Sg_request req_arr[SG_MAX_QUEUE]; /* used as singly-linked list */ 147 char force_packid; /* 1 -> pack_id input to read(), 0 -> ignored */ 148 char cmd_q; /* 1 -> allow command queuing, 0 -> don't */ 149 unsigned char next_cmd_len; /* 0: automatic, >0: use on next write() */ 150 char keep_orphan; /* 0 -> drop orphan (def), 1 -> keep for read() */ 151 char mmap_called; /* 0 -> mmap() never called on this fd */ 152 char res_in_use; /* 1 -> 'reserve' array in use */ 153 struct kref f_ref; 154 struct execute_work ew; 155 } Sg_fd; 156 157 typedef struct sg_device { /* holds the state of each scsi generic device */ 158 struct scsi_device *device; 159 wait_queue_head_t open_wait; /* queue open() when O_EXCL present */ 160 struct mutex open_rel_lock; /* held when in open() or release() */ 161 int sg_tablesize; /* adapter's max scatter-gather table size */ 162 u32 index; /* device index number */ 163 struct list_head sfds; 164 rwlock_t sfd_lock; /* protect access to sfd list */ 165 atomic_t detaching; /* 0->device usable, 1->device detaching */ 166 bool exclude; /* 1->open(O_EXCL) succeeded and is active */ 167 int open_cnt; /* count of opens (perhaps < num(sfds) ) */ 168 char sgdebug; /* 0->off, 1->sense, 9->dump dev, 10-> all devs */ 169 char name[DISK_NAME_LEN]; 170 struct cdev * cdev; /* char_dev [sysfs: /sys/cdev/major/sg<n>] */ 171 struct kref d_ref; 172 } Sg_device; 173 174 /* tasklet or soft irq callback */ 175 static void sg_rq_end_io(struct request *rq, blk_status_t status); 176 static int sg_start_req(Sg_request *srp, unsigned char *cmd); 177 static int sg_finish_rem_req(Sg_request * srp); 178 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size); 179 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, 180 Sg_request * srp); 181 static ssize_t sg_new_write(Sg_fd *sfp, struct file *file, 182 const char __user *buf, size_t count, int blocking, 183 int read_only, int sg_io_owned, Sg_request **o_srp); 184 static int sg_common_write(Sg_fd * sfp, Sg_request * srp, 185 unsigned char *cmnd, int timeout, int blocking); 186 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer); 187 static void sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp); 188 static void sg_build_reserve(Sg_fd * sfp, int req_size); 189 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size); 190 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp); 191 static Sg_fd *sg_add_sfp(Sg_device * sdp); 192 static void sg_remove_sfp(struct kref *); 193 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id); 194 static Sg_request *sg_add_request(Sg_fd * sfp); 195 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp); 196 static Sg_device *sg_get_dev(int dev); 197 static void sg_device_destroy(struct kref *kref); 198 199 #define SZ_SG_HEADER sizeof(struct sg_header) 200 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t) 201 #define SZ_SG_IOVEC sizeof(sg_iovec_t) 202 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t) 203 204 #define sg_printk(prefix, sdp, fmt, a...) \ 205 sdev_prefix_printk(prefix, (sdp)->device, (sdp)->name, fmt, ##a) 206 207 /* 208 * The SCSI interfaces that use read() and write() as an asynchronous variant of 209 * ioctl(..., SG_IO, ...) are fundamentally unsafe, since there are lots of ways 210 * to trigger read() and write() calls from various contexts with elevated 211 * privileges. This can lead to kernel memory corruption (e.g. if these 212 * interfaces are called through splice()) and privilege escalation inside 213 * userspace (e.g. if a process with access to such a device passes a file 214 * descriptor to a SUID binary as stdin/stdout/stderr). 215 * 216 * This function provides protection for the legacy API by restricting the 217 * calling context. 218 */ 219 static int sg_check_file_access(struct file *filp, const char *caller) 220 { 221 if (filp->f_cred != current_real_cred()) { 222 pr_err_once("%s: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n", 223 caller, task_tgid_vnr(current), current->comm); 224 return -EPERM; 225 } 226 if (uaccess_kernel()) { 227 pr_err_once("%s: process %d (%s) called from kernel context, this is not allowed.\n", 228 caller, task_tgid_vnr(current), current->comm); 229 return -EACCES; 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; 240 241 return blk_verify_command(cmd, filp->f_mode); 242 } 243 244 static int 245 open_wait(Sg_device *sdp, int flags) 246 { 247 int retval = 0; 248 249 if (flags & O_EXCL) { 250 while (sdp->open_cnt > 0) { 251 mutex_unlock(&sdp->open_rel_lock); 252 retval = wait_event_interruptible(sdp->open_wait, 253 (atomic_read(&sdp->detaching) || 254 !sdp->open_cnt)); 255 mutex_lock(&sdp->open_rel_lock); 256 257 if (retval) /* -ERESTARTSYS */ 258 return retval; 259 if (atomic_read(&sdp->detaching)) 260 return -ENODEV; 261 } 262 } else { 263 while (sdp->exclude) { 264 mutex_unlock(&sdp->open_rel_lock); 265 retval = wait_event_interruptible(sdp->open_wait, 266 (atomic_read(&sdp->detaching) || 267 !sdp->exclude)); 268 mutex_lock(&sdp->open_rel_lock); 269 270 if (retval) /* -ERESTARTSYS */ 271 return retval; 272 if (atomic_read(&sdp->detaching)) 273 return -ENODEV; 274 } 275 } 276 277 return retval; 278 } 279 280 /* Returns 0 on success, else a negated errno value */ 281 static int 282 sg_open(struct inode *inode, struct file *filp) 283 { 284 int dev = iminor(inode); 285 int flags = filp->f_flags; 286 struct request_queue *q; 287 Sg_device *sdp; 288 Sg_fd *sfp; 289 int retval; 290 291 nonseekable_open(inode, filp); 292 if ((flags & O_EXCL) && (O_RDONLY == (flags & O_ACCMODE))) 293 return -EPERM; /* Can't lock it with read only access */ 294 sdp = sg_get_dev(dev); 295 if (IS_ERR(sdp)) 296 return PTR_ERR(sdp); 297 298 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 299 "sg_open: flags=0x%x\n", flags)); 300 301 /* This driver's module count bumped by fops_get in <linux/fs.h> */ 302 /* Prevent the device driver from vanishing while we sleep */ 303 retval = scsi_device_get(sdp->device); 304 if (retval) 305 goto sg_put; 306 307 retval = scsi_autopm_get_device(sdp->device); 308 if (retval) 309 goto sdp_put; 310 311 /* scsi_block_when_processing_errors() may block so bypass 312 * check if O_NONBLOCK. Permits SCSI commands to be issued 313 * during error recovery. Tread carefully. */ 314 if (!((flags & O_NONBLOCK) || 315 scsi_block_when_processing_errors(sdp->device))) { 316 retval = -ENXIO; 317 /* we are in error recovery for this device */ 318 goto error_out; 319 } 320 321 mutex_lock(&sdp->open_rel_lock); 322 if (flags & O_NONBLOCK) { 323 if (flags & O_EXCL) { 324 if (sdp->open_cnt > 0) { 325 retval = -EBUSY; 326 goto error_mutex_locked; 327 } 328 } else { 329 if (sdp->exclude) { 330 retval = -EBUSY; 331 goto error_mutex_locked; 332 } 333 } 334 } else { 335 retval = open_wait(sdp, flags); 336 if (retval) /* -ERESTARTSYS or -ENODEV */ 337 goto error_mutex_locked; 338 } 339 340 /* N.B. at this point we are holding the open_rel_lock */ 341 if (flags & O_EXCL) 342 sdp->exclude = true; 343 344 if (sdp->open_cnt < 1) { /* no existing opens */ 345 sdp->sgdebug = 0; 346 q = sdp->device->request_queue; 347 sdp->sg_tablesize = queue_max_segments(q); 348 } 349 sfp = sg_add_sfp(sdp); 350 if (IS_ERR(sfp)) { 351 retval = PTR_ERR(sfp); 352 goto out_undo; 353 } 354 355 filp->private_data = sfp; 356 sdp->open_cnt++; 357 mutex_unlock(&sdp->open_rel_lock); 358 359 retval = 0; 360 sg_put: 361 kref_put(&sdp->d_ref, sg_device_destroy); 362 return retval; 363 364 out_undo: 365 if (flags & O_EXCL) { 366 sdp->exclude = false; /* undo if error */ 367 wake_up_interruptible(&sdp->open_wait); 368 } 369 error_mutex_locked: 370 mutex_unlock(&sdp->open_rel_lock); 371 error_out: 372 scsi_autopm_put_device(sdp->device); 373 sdp_put: 374 scsi_device_put(sdp->device); 375 goto sg_put; 376 } 377 378 /* Release resources associated with a successful sg_open() 379 * Returns 0 on success, else a negated errno value */ 380 static int 381 sg_release(struct inode *inode, struct file *filp) 382 { 383 Sg_device *sdp; 384 Sg_fd *sfp; 385 386 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 387 return -ENXIO; 388 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, "sg_release\n")); 389 390 mutex_lock(&sdp->open_rel_lock); 391 scsi_autopm_put_device(sdp->device); 392 kref_put(&sfp->f_ref, sg_remove_sfp); 393 sdp->open_cnt--; 394 395 /* possibly many open()s waiting on exlude clearing, start many; 396 * only open(O_EXCL)s wait on 0==open_cnt so only start one */ 397 if (sdp->exclude) { 398 sdp->exclude = false; 399 wake_up_interruptible_all(&sdp->open_wait); 400 } else if (0 == sdp->open_cnt) { 401 wake_up_interruptible(&sdp->open_wait); 402 } 403 mutex_unlock(&sdp->open_rel_lock); 404 return 0; 405 } 406 407 static int get_sg_io_pack_id(int *pack_id, void __user *buf, size_t count) 408 { 409 struct sg_header __user *old_hdr = buf; 410 int reply_len; 411 412 if (count >= SZ_SG_HEADER) { 413 /* negative reply_len means v3 format, otherwise v1/v2 */ 414 if (get_user(reply_len, &old_hdr->reply_len)) 415 return -EFAULT; 416 417 if (reply_len >= 0) 418 return get_user(*pack_id, &old_hdr->pack_id); 419 420 if (in_compat_syscall() && 421 count >= sizeof(struct compat_sg_io_hdr)) { 422 struct compat_sg_io_hdr __user *hp = buf; 423 424 return get_user(*pack_id, &hp->pack_id); 425 } 426 427 if (count >= sizeof(struct sg_io_hdr)) { 428 struct sg_io_hdr __user *hp = buf; 429 430 return get_user(*pack_id, &hp->pack_id); 431 } 432 } 433 434 /* no valid header was passed, so ignore the pack_id */ 435 *pack_id = -1; 436 return 0; 437 } 438 439 static ssize_t 440 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos) 441 { 442 Sg_device *sdp; 443 Sg_fd *sfp; 444 Sg_request *srp; 445 int req_pack_id = -1; 446 sg_io_hdr_t *hp; 447 struct sg_header *old_hdr; 448 int retval; 449 450 /* 451 * This could cause a response to be stranded. Close the associated 452 * file descriptor to free up any resources being held. 453 */ 454 retval = sg_check_file_access(filp, __func__); 455 if (retval) 456 return retval; 457 458 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 459 return -ENXIO; 460 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 461 "sg_read: count=%d\n", (int) count)); 462 463 if (sfp->force_packid) 464 retval = get_sg_io_pack_id(&req_pack_id, buf, count); 465 if (retval) 466 return retval; 467 468 srp = sg_get_rq_mark(sfp, req_pack_id); 469 if (!srp) { /* now wait on packet to arrive */ 470 if (atomic_read(&sdp->detaching)) 471 return -ENODEV; 472 if (filp->f_flags & O_NONBLOCK) 473 return -EAGAIN; 474 retval = wait_event_interruptible(sfp->read_wait, 475 (atomic_read(&sdp->detaching) || 476 (srp = sg_get_rq_mark(sfp, req_pack_id)))); 477 if (atomic_read(&sdp->detaching)) 478 return -ENODEV; 479 if (retval) 480 /* -ERESTARTSYS as signal hit process */ 481 return retval; 482 } 483 if (srp->header.interface_id != '\0') 484 return sg_new_read(sfp, buf, count, srp); 485 486 hp = &srp->header; 487 old_hdr = kzalloc(SZ_SG_HEADER, GFP_KERNEL); 488 if (!old_hdr) 489 return -ENOMEM; 490 491 old_hdr->reply_len = (int) hp->timeout; 492 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */ 493 old_hdr->pack_id = hp->pack_id; 494 old_hdr->twelve_byte = 495 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0; 496 old_hdr->target_status = hp->masked_status; 497 old_hdr->host_status = hp->host_status; 498 old_hdr->driver_status = hp->driver_status; 499 if ((CHECK_CONDITION & hp->masked_status) || 500 (srp->sense_b[0] & 0x70) == 0x70) { 501 old_hdr->driver_status = DRIVER_SENSE; 502 memcpy(old_hdr->sense_buffer, srp->sense_b, 503 sizeof (old_hdr->sense_buffer)); 504 } 505 switch (hp->host_status) { 506 /* This setup of 'result' is for backward compatibility and is best 507 ignored by the user who should use target, host + driver status */ 508 case DID_OK: 509 case DID_PASSTHROUGH: 510 case DID_SOFT_ERROR: 511 old_hdr->result = 0; 512 break; 513 case DID_NO_CONNECT: 514 case DID_BUS_BUSY: 515 case DID_TIME_OUT: 516 old_hdr->result = EBUSY; 517 break; 518 case DID_BAD_TARGET: 519 case DID_ABORT: 520 case DID_PARITY: 521 case DID_RESET: 522 case DID_BAD_INTR: 523 old_hdr->result = EIO; 524 break; 525 case DID_ERROR: 526 old_hdr->result = (srp->sense_b[0] == 0 && 527 hp->masked_status == GOOD) ? 0 : EIO; 528 break; 529 default: 530 old_hdr->result = EIO; 531 break; 532 } 533 534 /* Now copy the result back to the user buffer. */ 535 if (count >= SZ_SG_HEADER) { 536 if (copy_to_user(buf, old_hdr, SZ_SG_HEADER)) { 537 retval = -EFAULT; 538 goto free_old_hdr; 539 } 540 buf += SZ_SG_HEADER; 541 if (count > old_hdr->reply_len) 542 count = old_hdr->reply_len; 543 if (count > SZ_SG_HEADER) { 544 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) { 545 retval = -EFAULT; 546 goto free_old_hdr; 547 } 548 } 549 } else 550 count = (old_hdr->result == 0) ? 0 : -EIO; 551 sg_finish_rem_req(srp); 552 sg_remove_request(sfp, srp); 553 retval = count; 554 free_old_hdr: 555 kfree(old_hdr); 556 return retval; 557 } 558 559 static ssize_t 560 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp) 561 { 562 sg_io_hdr_t *hp = &srp->header; 563 int err = 0, err2; 564 int len; 565 566 if (in_compat_syscall()) { 567 if (count < sizeof(struct compat_sg_io_hdr)) { 568 err = -EINVAL; 569 goto err_out; 570 } 571 } else if (count < SZ_SG_IO_HDR) { 572 err = -EINVAL; 573 goto err_out; 574 } 575 hp->sb_len_wr = 0; 576 if ((hp->mx_sb_len > 0) && hp->sbp) { 577 if ((CHECK_CONDITION & hp->masked_status) || 578 (srp->sense_b[0] & 0x70) == 0x70) { 579 int sb_len = SCSI_SENSE_BUFFERSIZE; 580 sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len; 581 len = 8 + (int) srp->sense_b[7]; /* Additional sense length field */ 582 len = (len > sb_len) ? sb_len : len; 583 if (copy_to_user(hp->sbp, srp->sense_b, len)) { 584 err = -EFAULT; 585 goto err_out; 586 } 587 hp->driver_status = DRIVER_SENSE; 588 hp->sb_len_wr = len; 589 } 590 } 591 if (hp->masked_status || hp->host_status || hp->driver_status) 592 hp->info |= SG_INFO_CHECK; 593 err = put_sg_io_hdr(hp, buf); 594 err_out: 595 err2 = sg_finish_rem_req(srp); 596 sg_remove_request(sfp, srp); 597 return err ? : err2 ? : count; 598 } 599 600 static ssize_t 601 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos) 602 { 603 int mxsize, cmd_size, k; 604 int input_size, blocking; 605 unsigned char opcode; 606 Sg_device *sdp; 607 Sg_fd *sfp; 608 Sg_request *srp; 609 struct sg_header old_hdr; 610 sg_io_hdr_t *hp; 611 unsigned char cmnd[SG_MAX_CDB_SIZE]; 612 int retval; 613 614 retval = sg_check_file_access(filp, __func__); 615 if (retval) 616 return retval; 617 618 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 619 return -ENXIO; 620 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 621 "sg_write: count=%d\n", (int) count)); 622 if (atomic_read(&sdp->detaching)) 623 return -ENODEV; 624 if (!((filp->f_flags & O_NONBLOCK) || 625 scsi_block_when_processing_errors(sdp->device))) 626 return -ENXIO; 627 628 if (count < SZ_SG_HEADER) 629 return -EIO; 630 if (copy_from_user(&old_hdr, buf, SZ_SG_HEADER)) 631 return -EFAULT; 632 blocking = !(filp->f_flags & O_NONBLOCK); 633 if (old_hdr.reply_len < 0) 634 return sg_new_write(sfp, filp, buf, count, 635 blocking, 0, 0, NULL); 636 if (count < (SZ_SG_HEADER + 6)) 637 return -EIO; /* The minimum scsi command length is 6 bytes. */ 638 639 buf += SZ_SG_HEADER; 640 if (get_user(opcode, buf)) 641 return -EFAULT; 642 643 if (!(srp = sg_add_request(sfp))) { 644 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sdp, 645 "sg_write: queue full\n")); 646 return -EDOM; 647 } 648 mutex_lock(&sfp->f_mutex); 649 if (sfp->next_cmd_len > 0) { 650 cmd_size = sfp->next_cmd_len; 651 sfp->next_cmd_len = 0; /* reset so only this write() effected */ 652 } else { 653 cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */ 654 if ((opcode >= 0xc0) && old_hdr.twelve_byte) 655 cmd_size = 12; 656 } 657 mutex_unlock(&sfp->f_mutex); 658 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp, 659 "sg_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size)); 660 /* Determine buffer size. */ 661 input_size = count - cmd_size; 662 mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len; 663 mxsize -= SZ_SG_HEADER; 664 input_size -= SZ_SG_HEADER; 665 if (input_size < 0) { 666 sg_remove_request(sfp, srp); 667 return -EIO; /* User did not pass enough bytes for this command. */ 668 } 669 hp = &srp->header; 670 hp->interface_id = '\0'; /* indicator of old interface tunnelled */ 671 hp->cmd_len = (unsigned char) cmd_size; 672 hp->iovec_count = 0; 673 hp->mx_sb_len = 0; 674 if (input_size > 0) 675 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ? 676 SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV; 677 else 678 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE; 679 hp->dxfer_len = mxsize; 680 if ((hp->dxfer_direction == SG_DXFER_TO_DEV) || 681 (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV)) 682 hp->dxferp = (char __user *)buf + cmd_size; 683 else 684 hp->dxferp = NULL; 685 hp->sbp = NULL; 686 hp->timeout = old_hdr.reply_len; /* structure abuse ... */ 687 hp->flags = input_size; /* structure abuse ... */ 688 hp->pack_id = old_hdr.pack_id; 689 hp->usr_ptr = NULL; 690 if (copy_from_user(cmnd, buf, cmd_size)) { 691 sg_remove_request(sfp, srp); 692 return -EFAULT; 693 } 694 /* 695 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV, 696 * but is is possible that the app intended SG_DXFER_TO_DEV, because there 697 * is a non-zero input_size, so emit a warning. 698 */ 699 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) { 700 printk_ratelimited(KERN_WARNING 701 "sg_write: data in/out %d/%d bytes " 702 "for SCSI command 0x%x-- guessing " 703 "data in;\n program %s not setting " 704 "count and/or reply_len properly\n", 705 old_hdr.reply_len - (int)SZ_SG_HEADER, 706 input_size, (unsigned int) cmnd[0], 707 current->comm); 708 } 709 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking); 710 return (k < 0) ? k : count; 711 } 712 713 static ssize_t 714 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf, 715 size_t count, int blocking, int read_only, int sg_io_owned, 716 Sg_request **o_srp) 717 { 718 int k; 719 Sg_request *srp; 720 sg_io_hdr_t *hp; 721 unsigned char cmnd[SG_MAX_CDB_SIZE]; 722 int timeout; 723 unsigned long ul_timeout; 724 725 if (count < SZ_SG_IO_HDR) 726 return -EINVAL; 727 728 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */ 729 if (!(srp = sg_add_request(sfp))) { 730 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp, 731 "sg_new_write: queue full\n")); 732 return -EDOM; 733 } 734 srp->sg_io_owned = sg_io_owned; 735 hp = &srp->header; 736 if (get_sg_io_hdr(hp, buf)) { 737 sg_remove_request(sfp, srp); 738 return -EFAULT; 739 } 740 if (hp->interface_id != 'S') { 741 sg_remove_request(sfp, srp); 742 return -ENOSYS; 743 } 744 if (hp->flags & SG_FLAG_MMAP_IO) { 745 if (hp->dxfer_len > sfp->reserve.bufflen) { 746 sg_remove_request(sfp, srp); 747 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */ 748 } 749 if (hp->flags & SG_FLAG_DIRECT_IO) { 750 sg_remove_request(sfp, srp); 751 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */ 752 } 753 if (sfp->res_in_use) { 754 sg_remove_request(sfp, srp); 755 return -EBUSY; /* reserve buffer already being used */ 756 } 757 } 758 ul_timeout = msecs_to_jiffies(srp->header.timeout); 759 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX; 760 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) { 761 sg_remove_request(sfp, srp); 762 return -EMSGSIZE; 763 } 764 if (copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) { 765 sg_remove_request(sfp, srp); 766 return -EFAULT; 767 } 768 if (read_only && sg_allow_access(file, cmnd)) { 769 sg_remove_request(sfp, srp); 770 return -EPERM; 771 } 772 k = sg_common_write(sfp, srp, cmnd, timeout, blocking); 773 if (k < 0) 774 return k; 775 if (o_srp) 776 *o_srp = srp; 777 return count; 778 } 779 780 static int 781 sg_common_write(Sg_fd * sfp, Sg_request * srp, 782 unsigned char *cmnd, int timeout, int blocking) 783 { 784 int k, at_head; 785 Sg_device *sdp = sfp->parentdp; 786 sg_io_hdr_t *hp = &srp->header; 787 788 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */ 789 hp->status = 0; 790 hp->masked_status = 0; 791 hp->msg_status = 0; 792 hp->info = 0; 793 hp->host_status = 0; 794 hp->driver_status = 0; 795 hp->resid = 0; 796 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 797 "sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n", 798 (int) cmnd[0], (int) hp->cmd_len)); 799 800 if (hp->dxfer_len >= SZ_256M) { 801 sg_remove_request(sfp, srp); 802 return -EINVAL; 803 } 804 805 k = sg_start_req(srp, cmnd); 806 if (k) { 807 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp, 808 "sg_common_write: start_req err=%d\n", k)); 809 sg_finish_rem_req(srp); 810 sg_remove_request(sfp, srp); 811 return k; /* probably out of space --> ENOMEM */ 812 } 813 if (atomic_read(&sdp->detaching)) { 814 if (srp->bio) { 815 scsi_req_free_cmd(scsi_req(srp->rq)); 816 blk_put_request(srp->rq); 817 srp->rq = NULL; 818 } 819 820 sg_finish_rem_req(srp); 821 sg_remove_request(sfp, srp); 822 return -ENODEV; 823 } 824 825 hp->duration = jiffies_to_msecs(jiffies); 826 if (hp->interface_id != '\0' && /* v3 (or later) interface */ 827 (SG_FLAG_Q_AT_TAIL & hp->flags)) 828 at_head = 0; 829 else 830 at_head = 1; 831 832 srp->rq->timeout = timeout; 833 kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */ 834 blk_execute_rq_nowait(NULL, srp->rq, at_head, sg_rq_end_io); 835 return 0; 836 } 837 838 static int srp_done(Sg_fd *sfp, Sg_request *srp) 839 { 840 unsigned long flags; 841 int ret; 842 843 read_lock_irqsave(&sfp->rq_list_lock, flags); 844 ret = srp->done; 845 read_unlock_irqrestore(&sfp->rq_list_lock, flags); 846 return ret; 847 } 848 849 static int max_sectors_bytes(struct request_queue *q) 850 { 851 unsigned int max_sectors = queue_max_sectors(q); 852 853 max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9); 854 855 return max_sectors << 9; 856 } 857 858 static void 859 sg_fill_request_table(Sg_fd *sfp, sg_req_info_t *rinfo) 860 { 861 Sg_request *srp; 862 int val; 863 unsigned int ms; 864 865 val = 0; 866 list_for_each_entry(srp, &sfp->rq_list, entry) { 867 if (val >= SG_MAX_QUEUE) 868 break; 869 rinfo[val].req_state = srp->done + 1; 870 rinfo[val].problem = 871 srp->header.masked_status & 872 srp->header.host_status & 873 srp->header.driver_status; 874 if (srp->done) 875 rinfo[val].duration = 876 srp->header.duration; 877 else { 878 ms = jiffies_to_msecs(jiffies); 879 rinfo[val].duration = 880 (ms > srp->header.duration) ? 881 (ms - srp->header.duration) : 0; 882 } 883 rinfo[val].orphan = srp->orphan; 884 rinfo[val].sg_io_owned = srp->sg_io_owned; 885 rinfo[val].pack_id = srp->header.pack_id; 886 rinfo[val].usr_ptr = srp->header.usr_ptr; 887 val++; 888 } 889 } 890 891 #ifdef CONFIG_COMPAT 892 struct compat_sg_req_info { /* used by SG_GET_REQUEST_TABLE ioctl() */ 893 char req_state; 894 char orphan; 895 char sg_io_owned; 896 char problem; 897 int pack_id; 898 compat_uptr_t usr_ptr; 899 unsigned int duration; 900 int unused; 901 }; 902 903 static int put_compat_request_table(struct compat_sg_req_info __user *o, 904 struct sg_req_info *rinfo) 905 { 906 int i; 907 for (i = 0; i < SG_MAX_QUEUE; i++) { 908 if (copy_to_user(o + i, rinfo + i, offsetof(sg_req_info_t, usr_ptr)) || 909 put_user((uintptr_t)rinfo[i].usr_ptr, &o[i].usr_ptr) || 910 put_user(rinfo[i].duration, &o[i].duration) || 911 put_user(rinfo[i].unused, &o[i].unused)) 912 return -EFAULT; 913 } 914 return 0; 915 } 916 #endif 917 918 static long 919 sg_ioctl_common(struct file *filp, Sg_device *sdp, Sg_fd *sfp, 920 unsigned int cmd_in, void __user *p) 921 { 922 int __user *ip = p; 923 int result, val, read_only; 924 Sg_request *srp; 925 unsigned long iflags; 926 927 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 928 "sg_ioctl: cmd=0x%x\n", (int) cmd_in)); 929 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE)); 930 931 switch (cmd_in) { 932 case SG_IO: 933 if (atomic_read(&sdp->detaching)) 934 return -ENODEV; 935 if (!scsi_block_when_processing_errors(sdp->device)) 936 return -ENXIO; 937 result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR, 938 1, read_only, 1, &srp); 939 if (result < 0) 940 return result; 941 result = wait_event_interruptible(sfp->read_wait, 942 (srp_done(sfp, srp) || atomic_read(&sdp->detaching))); 943 if (atomic_read(&sdp->detaching)) 944 return -ENODEV; 945 write_lock_irq(&sfp->rq_list_lock); 946 if (srp->done) { 947 srp->done = 2; 948 write_unlock_irq(&sfp->rq_list_lock); 949 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp); 950 return (result < 0) ? result : 0; 951 } 952 srp->orphan = 1; 953 write_unlock_irq(&sfp->rq_list_lock); 954 return result; /* -ERESTARTSYS because signal hit process */ 955 case SG_SET_TIMEOUT: 956 result = get_user(val, ip); 957 if (result) 958 return result; 959 if (val < 0) 960 return -EIO; 961 if (val >= mult_frac((s64)INT_MAX, USER_HZ, HZ)) 962 val = min_t(s64, mult_frac((s64)INT_MAX, USER_HZ, HZ), 963 INT_MAX); 964 sfp->timeout_user = val; 965 sfp->timeout = mult_frac(val, HZ, USER_HZ); 966 967 return 0; 968 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */ 969 /* strange ..., for backward compatibility */ 970 return sfp->timeout_user; 971 case SG_SET_FORCE_LOW_DMA: 972 /* 973 * N.B. This ioctl never worked properly, but failed to 974 * return an error value. So returning '0' to keep compability 975 * with legacy applications. 976 */ 977 return 0; 978 case SG_GET_LOW_DMA: 979 return put_user(0, ip); 980 case SG_GET_SCSI_ID: 981 { 982 sg_scsi_id_t v; 983 984 if (atomic_read(&sdp->detaching)) 985 return -ENODEV; 986 memset(&v, 0, sizeof(v)); 987 v.host_no = sdp->device->host->host_no; 988 v.channel = sdp->device->channel; 989 v.scsi_id = sdp->device->id; 990 v.lun = sdp->device->lun; 991 v.scsi_type = sdp->device->type; 992 v.h_cmd_per_lun = sdp->device->host->cmd_per_lun; 993 v.d_queue_depth = sdp->device->queue_depth; 994 if (copy_to_user(p, &v, sizeof(sg_scsi_id_t))) 995 return -EFAULT; 996 return 0; 997 } 998 case SG_SET_FORCE_PACK_ID: 999 result = get_user(val, ip); 1000 if (result) 1001 return result; 1002 sfp->force_packid = val ? 1 : 0; 1003 return 0; 1004 case SG_GET_PACK_ID: 1005 read_lock_irqsave(&sfp->rq_list_lock, iflags); 1006 list_for_each_entry(srp, &sfp->rq_list, entry) { 1007 if ((1 == srp->done) && (!srp->sg_io_owned)) { 1008 read_unlock_irqrestore(&sfp->rq_list_lock, 1009 iflags); 1010 return put_user(srp->header.pack_id, ip); 1011 } 1012 } 1013 read_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1014 return put_user(-1, ip); 1015 case SG_GET_NUM_WAITING: 1016 read_lock_irqsave(&sfp->rq_list_lock, iflags); 1017 val = 0; 1018 list_for_each_entry(srp, &sfp->rq_list, entry) { 1019 if ((1 == srp->done) && (!srp->sg_io_owned)) 1020 ++val; 1021 } 1022 read_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1023 return put_user(val, ip); 1024 case SG_GET_SG_TABLESIZE: 1025 return put_user(sdp->sg_tablesize, ip); 1026 case SG_SET_RESERVED_SIZE: 1027 result = get_user(val, ip); 1028 if (result) 1029 return result; 1030 if (val < 0) 1031 return -EINVAL; 1032 val = min_t(int, val, 1033 max_sectors_bytes(sdp->device->request_queue)); 1034 mutex_lock(&sfp->f_mutex); 1035 if (val != sfp->reserve.bufflen) { 1036 if (sfp->mmap_called || 1037 sfp->res_in_use) { 1038 mutex_unlock(&sfp->f_mutex); 1039 return -EBUSY; 1040 } 1041 1042 sg_remove_scat(sfp, &sfp->reserve); 1043 sg_build_reserve(sfp, val); 1044 } 1045 mutex_unlock(&sfp->f_mutex); 1046 return 0; 1047 case SG_GET_RESERVED_SIZE: 1048 val = min_t(int, sfp->reserve.bufflen, 1049 max_sectors_bytes(sdp->device->request_queue)); 1050 return put_user(val, ip); 1051 case SG_SET_COMMAND_Q: 1052 result = get_user(val, ip); 1053 if (result) 1054 return result; 1055 sfp->cmd_q = val ? 1 : 0; 1056 return 0; 1057 case SG_GET_COMMAND_Q: 1058 return put_user((int) sfp->cmd_q, ip); 1059 case SG_SET_KEEP_ORPHAN: 1060 result = get_user(val, ip); 1061 if (result) 1062 return result; 1063 sfp->keep_orphan = val; 1064 return 0; 1065 case SG_GET_KEEP_ORPHAN: 1066 return put_user((int) sfp->keep_orphan, ip); 1067 case SG_NEXT_CMD_LEN: 1068 result = get_user(val, ip); 1069 if (result) 1070 return result; 1071 if (val > SG_MAX_CDB_SIZE) 1072 return -ENOMEM; 1073 sfp->next_cmd_len = (val > 0) ? val : 0; 1074 return 0; 1075 case SG_GET_VERSION_NUM: 1076 return put_user(sg_version_num, ip); 1077 case SG_GET_ACCESS_COUNT: 1078 /* faked - we don't have a real access count anymore */ 1079 val = (sdp->device ? 1 : 0); 1080 return put_user(val, ip); 1081 case SG_GET_REQUEST_TABLE: 1082 { 1083 sg_req_info_t *rinfo; 1084 1085 rinfo = kcalloc(SG_MAX_QUEUE, SZ_SG_REQ_INFO, 1086 GFP_KERNEL); 1087 if (!rinfo) 1088 return -ENOMEM; 1089 read_lock_irqsave(&sfp->rq_list_lock, iflags); 1090 sg_fill_request_table(sfp, rinfo); 1091 read_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1092 #ifdef CONFIG_COMPAT 1093 if (in_compat_syscall()) 1094 result = put_compat_request_table(p, rinfo); 1095 else 1096 #endif 1097 result = copy_to_user(p, rinfo, 1098 SZ_SG_REQ_INFO * SG_MAX_QUEUE); 1099 result = result ? -EFAULT : 0; 1100 kfree(rinfo); 1101 return result; 1102 } 1103 case SG_EMULATED_HOST: 1104 if (atomic_read(&sdp->detaching)) 1105 return -ENODEV; 1106 return put_user(sdp->device->host->hostt->emulated, ip); 1107 case SCSI_IOCTL_SEND_COMMAND: 1108 if (atomic_read(&sdp->detaching)) 1109 return -ENODEV; 1110 return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p); 1111 case SG_SET_DEBUG: 1112 result = get_user(val, ip); 1113 if (result) 1114 return result; 1115 sdp->sgdebug = (char) val; 1116 return 0; 1117 case BLKSECTGET: 1118 return put_user(max_sectors_bytes(sdp->device->request_queue), 1119 ip); 1120 case BLKTRACESETUP: 1121 return blk_trace_setup(sdp->device->request_queue, sdp->name, 1122 MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1123 NULL, p); 1124 case BLKTRACESTART: 1125 return blk_trace_startstop(sdp->device->request_queue, 1); 1126 case BLKTRACESTOP: 1127 return blk_trace_startstop(sdp->device->request_queue, 0); 1128 case BLKTRACETEARDOWN: 1129 return blk_trace_remove(sdp->device->request_queue); 1130 case SCSI_IOCTL_GET_IDLUN: 1131 case SCSI_IOCTL_GET_BUS_NUMBER: 1132 case SCSI_IOCTL_PROBE_HOST: 1133 case SG_GET_TRANSFORM: 1134 case SG_SCSI_RESET: 1135 if (atomic_read(&sdp->detaching)) 1136 return -ENODEV; 1137 break; 1138 default: 1139 if (read_only) 1140 return -EPERM; /* don't know so take safe approach */ 1141 break; 1142 } 1143 1144 result = scsi_ioctl_block_when_processing_errors(sdp->device, 1145 cmd_in, filp->f_flags & O_NDELAY); 1146 if (result) 1147 return result; 1148 1149 return -ENOIOCTLCMD; 1150 } 1151 1152 static long 1153 sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg) 1154 { 1155 void __user *p = (void __user *)arg; 1156 Sg_device *sdp; 1157 Sg_fd *sfp; 1158 int ret; 1159 1160 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 1161 return -ENXIO; 1162 1163 ret = sg_ioctl_common(filp, sdp, sfp, cmd_in, p); 1164 if (ret != -ENOIOCTLCMD) 1165 return ret; 1166 1167 return scsi_ioctl(sdp->device, cmd_in, p); 1168 } 1169 1170 #ifdef CONFIG_COMPAT 1171 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg) 1172 { 1173 void __user *p = compat_ptr(arg); 1174 Sg_device *sdp; 1175 Sg_fd *sfp; 1176 int ret; 1177 1178 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 1179 return -ENXIO; 1180 1181 ret = sg_ioctl_common(filp, sdp, sfp, cmd_in, p); 1182 if (ret != -ENOIOCTLCMD) 1183 return ret; 1184 1185 return scsi_compat_ioctl(sdp->device, cmd_in, p); 1186 } 1187 #endif 1188 1189 static __poll_t 1190 sg_poll(struct file *filp, poll_table * wait) 1191 { 1192 __poll_t res = 0; 1193 Sg_device *sdp; 1194 Sg_fd *sfp; 1195 Sg_request *srp; 1196 int count = 0; 1197 unsigned long iflags; 1198 1199 sfp = filp->private_data; 1200 if (!sfp) 1201 return EPOLLERR; 1202 sdp = sfp->parentdp; 1203 if (!sdp) 1204 return EPOLLERR; 1205 poll_wait(filp, &sfp->read_wait, wait); 1206 read_lock_irqsave(&sfp->rq_list_lock, iflags); 1207 list_for_each_entry(srp, &sfp->rq_list, entry) { 1208 /* if any read waiting, flag it */ 1209 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned)) 1210 res = EPOLLIN | EPOLLRDNORM; 1211 ++count; 1212 } 1213 read_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1214 1215 if (atomic_read(&sdp->detaching)) 1216 res |= EPOLLHUP; 1217 else if (!sfp->cmd_q) { 1218 if (0 == count) 1219 res |= EPOLLOUT | EPOLLWRNORM; 1220 } else if (count < SG_MAX_QUEUE) 1221 res |= EPOLLOUT | EPOLLWRNORM; 1222 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 1223 "sg_poll: res=0x%x\n", (__force u32) res)); 1224 return res; 1225 } 1226 1227 static int 1228 sg_fasync(int fd, struct file *filp, int mode) 1229 { 1230 Sg_device *sdp; 1231 Sg_fd *sfp; 1232 1233 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 1234 return -ENXIO; 1235 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 1236 "sg_fasync: mode=%d\n", mode)); 1237 1238 return fasync_helper(fd, filp, mode, &sfp->async_qp); 1239 } 1240 1241 static vm_fault_t 1242 sg_vma_fault(struct vm_fault *vmf) 1243 { 1244 struct vm_area_struct *vma = vmf->vma; 1245 Sg_fd *sfp; 1246 unsigned long offset, len, sa; 1247 Sg_scatter_hold *rsv_schp; 1248 int k, length; 1249 1250 if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data))) 1251 return VM_FAULT_SIGBUS; 1252 rsv_schp = &sfp->reserve; 1253 offset = vmf->pgoff << PAGE_SHIFT; 1254 if (offset >= rsv_schp->bufflen) 1255 return VM_FAULT_SIGBUS; 1256 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp, 1257 "sg_vma_fault: offset=%lu, scatg=%d\n", 1258 offset, rsv_schp->k_use_sg)); 1259 sa = vma->vm_start; 1260 length = 1 << (PAGE_SHIFT + rsv_schp->page_order); 1261 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) { 1262 len = vma->vm_end - sa; 1263 len = (len < length) ? len : length; 1264 if (offset < len) { 1265 struct page *page = nth_page(rsv_schp->pages[k], 1266 offset >> PAGE_SHIFT); 1267 get_page(page); /* increment page count */ 1268 vmf->page = page; 1269 return 0; /* success */ 1270 } 1271 sa += len; 1272 offset -= len; 1273 } 1274 1275 return VM_FAULT_SIGBUS; 1276 } 1277 1278 static const struct vm_operations_struct sg_mmap_vm_ops = { 1279 .fault = sg_vma_fault, 1280 }; 1281 1282 static int 1283 sg_mmap(struct file *filp, struct vm_area_struct *vma) 1284 { 1285 Sg_fd *sfp; 1286 unsigned long req_sz, len, sa; 1287 Sg_scatter_hold *rsv_schp; 1288 int k, length; 1289 int ret = 0; 1290 1291 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data))) 1292 return -ENXIO; 1293 req_sz = vma->vm_end - vma->vm_start; 1294 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp, 1295 "sg_mmap starting, vm_start=%p, len=%d\n", 1296 (void *) vma->vm_start, (int) req_sz)); 1297 if (vma->vm_pgoff) 1298 return -EINVAL; /* want no offset */ 1299 rsv_schp = &sfp->reserve; 1300 mutex_lock(&sfp->f_mutex); 1301 if (req_sz > rsv_schp->bufflen) { 1302 ret = -ENOMEM; /* cannot map more than reserved buffer */ 1303 goto out; 1304 } 1305 1306 sa = vma->vm_start; 1307 length = 1 << (PAGE_SHIFT + rsv_schp->page_order); 1308 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) { 1309 len = vma->vm_end - sa; 1310 len = (len < length) ? len : length; 1311 sa += len; 1312 } 1313 1314 sfp->mmap_called = 1; 1315 vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP; 1316 vma->vm_private_data = sfp; 1317 vma->vm_ops = &sg_mmap_vm_ops; 1318 out: 1319 mutex_unlock(&sfp->f_mutex); 1320 return ret; 1321 } 1322 1323 static void 1324 sg_rq_end_io_usercontext(struct work_struct *work) 1325 { 1326 struct sg_request *srp = container_of(work, struct sg_request, ew.work); 1327 struct sg_fd *sfp = srp->parentfp; 1328 1329 sg_finish_rem_req(srp); 1330 sg_remove_request(sfp, srp); 1331 kref_put(&sfp->f_ref, sg_remove_sfp); 1332 } 1333 1334 /* 1335 * This function is a "bottom half" handler that is called by the mid 1336 * level when a command is completed (or has failed). 1337 */ 1338 static void 1339 sg_rq_end_io(struct request *rq, blk_status_t status) 1340 { 1341 struct sg_request *srp = rq->end_io_data; 1342 struct scsi_request *req = scsi_req(rq); 1343 Sg_device *sdp; 1344 Sg_fd *sfp; 1345 unsigned long iflags; 1346 unsigned int ms; 1347 char *sense; 1348 int result, resid, done = 1; 1349 1350 if (WARN_ON(srp->done != 0)) 1351 return; 1352 1353 sfp = srp->parentfp; 1354 if (WARN_ON(sfp == NULL)) 1355 return; 1356 1357 sdp = sfp->parentdp; 1358 if (unlikely(atomic_read(&sdp->detaching))) 1359 pr_info("%s: device detaching\n", __func__); 1360 1361 sense = req->sense; 1362 result = req->result; 1363 resid = req->resid_len; 1364 1365 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp, 1366 "sg_cmd_done: pack_id=%d, res=0x%x\n", 1367 srp->header.pack_id, result)); 1368 srp->header.resid = resid; 1369 ms = jiffies_to_msecs(jiffies); 1370 srp->header.duration = (ms > srp->header.duration) ? 1371 (ms - srp->header.duration) : 0; 1372 if (0 != result) { 1373 struct scsi_sense_hdr sshdr; 1374 1375 srp->header.status = 0xff & result; 1376 srp->header.masked_status = status_byte(result); 1377 srp->header.msg_status = COMMAND_COMPLETE; 1378 srp->header.host_status = host_byte(result); 1379 srp->header.driver_status = driver_byte(result); 1380 if ((sdp->sgdebug > 0) && 1381 ((CHECK_CONDITION == srp->header.masked_status) || 1382 (COMMAND_TERMINATED == srp->header.masked_status))) 1383 __scsi_print_sense(sdp->device, __func__, sense, 1384 SCSI_SENSE_BUFFERSIZE); 1385 1386 /* Following if statement is a patch supplied by Eric Youngdale */ 1387 if (driver_byte(result) != 0 1388 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr) 1389 && !scsi_sense_is_deferred(&sshdr) 1390 && sshdr.sense_key == UNIT_ATTENTION 1391 && sdp->device->removable) { 1392 /* Detected possible disc change. Set the bit - this */ 1393 /* may be used if there are filesystems using this device */ 1394 sdp->device->changed = 1; 1395 } 1396 } 1397 1398 if (req->sense_len) 1399 memcpy(srp->sense_b, req->sense, SCSI_SENSE_BUFFERSIZE); 1400 1401 /* Rely on write phase to clean out srp status values, so no "else" */ 1402 1403 /* 1404 * Free the request as soon as it is complete so that its resources 1405 * can be reused without waiting for userspace to read() the 1406 * result. But keep the associated bio (if any) around until 1407 * blk_rq_unmap_user() can be called from user context. 1408 */ 1409 srp->rq = NULL; 1410 scsi_req_free_cmd(scsi_req(rq)); 1411 blk_put_request(rq); 1412 1413 write_lock_irqsave(&sfp->rq_list_lock, iflags); 1414 if (unlikely(srp->orphan)) { 1415 if (sfp->keep_orphan) 1416 srp->sg_io_owned = 0; 1417 else 1418 done = 0; 1419 } 1420 srp->done = done; 1421 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1422 1423 if (likely(done)) { 1424 /* Now wake up any sg_read() that is waiting for this 1425 * packet. 1426 */ 1427 wake_up_interruptible(&sfp->read_wait); 1428 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN); 1429 kref_put(&sfp->f_ref, sg_remove_sfp); 1430 } else { 1431 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext); 1432 schedule_work(&srp->ew.work); 1433 } 1434 } 1435 1436 static const struct file_operations sg_fops = { 1437 .owner = THIS_MODULE, 1438 .read = sg_read, 1439 .write = sg_write, 1440 .poll = sg_poll, 1441 .unlocked_ioctl = sg_ioctl, 1442 #ifdef CONFIG_COMPAT 1443 .compat_ioctl = sg_compat_ioctl, 1444 #endif 1445 .open = sg_open, 1446 .mmap = sg_mmap, 1447 .release = sg_release, 1448 .fasync = sg_fasync, 1449 .llseek = no_llseek, 1450 }; 1451 1452 static struct class *sg_sysfs_class; 1453 1454 static int sg_sysfs_valid = 0; 1455 1456 static Sg_device * 1457 sg_alloc(struct scsi_device *scsidp) 1458 { 1459 struct request_queue *q = scsidp->request_queue; 1460 Sg_device *sdp; 1461 unsigned long iflags; 1462 int error; 1463 u32 k; 1464 1465 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL); 1466 if (!sdp) { 1467 sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device " 1468 "failure\n", __func__); 1469 return ERR_PTR(-ENOMEM); 1470 } 1471 1472 idr_preload(GFP_KERNEL); 1473 write_lock_irqsave(&sg_index_lock, iflags); 1474 1475 error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT); 1476 if (error < 0) { 1477 if (error == -ENOSPC) { 1478 sdev_printk(KERN_WARNING, scsidp, 1479 "Unable to attach sg device type=%d, minor number exceeds %d\n", 1480 scsidp->type, SG_MAX_DEVS - 1); 1481 error = -ENODEV; 1482 } else { 1483 sdev_printk(KERN_WARNING, scsidp, "%s: idr " 1484 "allocation Sg_device failure: %d\n", 1485 __func__, error); 1486 } 1487 goto out_unlock; 1488 } 1489 k = error; 1490 1491 SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp, 1492 "sg_alloc: dev=%d \n", k)); 1493 sprintf(sdp->name, "sg%d", k); 1494 sdp->device = scsidp; 1495 mutex_init(&sdp->open_rel_lock); 1496 INIT_LIST_HEAD(&sdp->sfds); 1497 init_waitqueue_head(&sdp->open_wait); 1498 atomic_set(&sdp->detaching, 0); 1499 rwlock_init(&sdp->sfd_lock); 1500 sdp->sg_tablesize = queue_max_segments(q); 1501 sdp->index = k; 1502 kref_init(&sdp->d_ref); 1503 error = 0; 1504 1505 out_unlock: 1506 write_unlock_irqrestore(&sg_index_lock, iflags); 1507 idr_preload_end(); 1508 1509 if (error) { 1510 kfree(sdp); 1511 return ERR_PTR(error); 1512 } 1513 return sdp; 1514 } 1515 1516 static int 1517 sg_add_device(struct device *cl_dev, struct class_interface *cl_intf) 1518 { 1519 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent); 1520 Sg_device *sdp = NULL; 1521 struct cdev * cdev = NULL; 1522 int error; 1523 unsigned long iflags; 1524 1525 error = -ENOMEM; 1526 cdev = cdev_alloc(); 1527 if (!cdev) { 1528 pr_warn("%s: cdev_alloc failed\n", __func__); 1529 goto out; 1530 } 1531 cdev->owner = THIS_MODULE; 1532 cdev->ops = &sg_fops; 1533 1534 sdp = sg_alloc(scsidp); 1535 if (IS_ERR(sdp)) { 1536 pr_warn("%s: sg_alloc failed\n", __func__); 1537 error = PTR_ERR(sdp); 1538 goto out; 1539 } 1540 1541 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1); 1542 if (error) 1543 goto cdev_add_err; 1544 1545 sdp->cdev = cdev; 1546 if (sg_sysfs_valid) { 1547 struct device *sg_class_member; 1548 1549 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent, 1550 MKDEV(SCSI_GENERIC_MAJOR, 1551 sdp->index), 1552 sdp, "%s", sdp->name); 1553 if (IS_ERR(sg_class_member)) { 1554 pr_err("%s: device_create failed\n", __func__); 1555 error = PTR_ERR(sg_class_member); 1556 goto cdev_add_err; 1557 } 1558 error = sysfs_create_link(&scsidp->sdev_gendev.kobj, 1559 &sg_class_member->kobj, "generic"); 1560 if (error) 1561 pr_err("%s: unable to make symlink 'generic' back " 1562 "to sg%d\n", __func__, sdp->index); 1563 } else 1564 pr_warn("%s: sg_sys Invalid\n", __func__); 1565 1566 sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d " 1567 "type %d\n", sdp->index, scsidp->type); 1568 1569 dev_set_drvdata(cl_dev, sdp); 1570 1571 return 0; 1572 1573 cdev_add_err: 1574 write_lock_irqsave(&sg_index_lock, iflags); 1575 idr_remove(&sg_index_idr, sdp->index); 1576 write_unlock_irqrestore(&sg_index_lock, iflags); 1577 kfree(sdp); 1578 1579 out: 1580 if (cdev) 1581 cdev_del(cdev); 1582 return error; 1583 } 1584 1585 static void 1586 sg_device_destroy(struct kref *kref) 1587 { 1588 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref); 1589 unsigned long flags; 1590 1591 /* CAUTION! Note that the device can still be found via idr_find() 1592 * even though the refcount is 0. Therefore, do idr_remove() BEFORE 1593 * any other cleanup. 1594 */ 1595 1596 write_lock_irqsave(&sg_index_lock, flags); 1597 idr_remove(&sg_index_idr, sdp->index); 1598 write_unlock_irqrestore(&sg_index_lock, flags); 1599 1600 SCSI_LOG_TIMEOUT(3, 1601 sg_printk(KERN_INFO, sdp, "sg_device_destroy\n")); 1602 1603 kfree(sdp); 1604 } 1605 1606 static void 1607 sg_remove_device(struct device *cl_dev, struct class_interface *cl_intf) 1608 { 1609 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent); 1610 Sg_device *sdp = dev_get_drvdata(cl_dev); 1611 unsigned long iflags; 1612 Sg_fd *sfp; 1613 int val; 1614 1615 if (!sdp) 1616 return; 1617 /* want sdp->detaching non-zero as soon as possible */ 1618 val = atomic_inc_return(&sdp->detaching); 1619 if (val > 1) 1620 return; /* only want to do following once per device */ 1621 1622 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 1623 "%s\n", __func__)); 1624 1625 read_lock_irqsave(&sdp->sfd_lock, iflags); 1626 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) { 1627 wake_up_interruptible_all(&sfp->read_wait); 1628 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP); 1629 } 1630 wake_up_interruptible_all(&sdp->open_wait); 1631 read_unlock_irqrestore(&sdp->sfd_lock, iflags); 1632 1633 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic"); 1634 device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index)); 1635 cdev_del(sdp->cdev); 1636 sdp->cdev = NULL; 1637 1638 kref_put(&sdp->d_ref, sg_device_destroy); 1639 } 1640 1641 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR); 1642 module_param_named(def_reserved_size, def_reserved_size, int, 1643 S_IRUGO | S_IWUSR); 1644 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR); 1645 1646 MODULE_AUTHOR("Douglas Gilbert"); 1647 MODULE_DESCRIPTION("SCSI generic (sg) driver"); 1648 MODULE_LICENSE("GPL"); 1649 MODULE_VERSION(SG_VERSION_STR); 1650 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR); 1651 1652 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element " 1653 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))"); 1654 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd"); 1655 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))"); 1656 1657 static int __init 1658 init_sg(void) 1659 { 1660 int rc; 1661 1662 if (scatter_elem_sz < PAGE_SIZE) { 1663 scatter_elem_sz = PAGE_SIZE; 1664 scatter_elem_sz_prev = scatter_elem_sz; 1665 } 1666 if (def_reserved_size >= 0) 1667 sg_big_buff = def_reserved_size; 1668 else 1669 def_reserved_size = sg_big_buff; 1670 1671 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), 1672 SG_MAX_DEVS, "sg"); 1673 if (rc) 1674 return rc; 1675 sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic"); 1676 if ( IS_ERR(sg_sysfs_class) ) { 1677 rc = PTR_ERR(sg_sysfs_class); 1678 goto err_out; 1679 } 1680 sg_sysfs_valid = 1; 1681 rc = scsi_register_interface(&sg_interface); 1682 if (0 == rc) { 1683 #ifdef CONFIG_SCSI_PROC_FS 1684 sg_proc_init(); 1685 #endif /* CONFIG_SCSI_PROC_FS */ 1686 return 0; 1687 } 1688 class_destroy(sg_sysfs_class); 1689 err_out: 1690 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS); 1691 return rc; 1692 } 1693 1694 static void __exit 1695 exit_sg(void) 1696 { 1697 #ifdef CONFIG_SCSI_PROC_FS 1698 remove_proc_subtree("scsi/sg", NULL); 1699 #endif /* CONFIG_SCSI_PROC_FS */ 1700 scsi_unregister_interface(&sg_interface); 1701 class_destroy(sg_sysfs_class); 1702 sg_sysfs_valid = 0; 1703 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), 1704 SG_MAX_DEVS); 1705 idr_destroy(&sg_index_idr); 1706 } 1707 1708 static int 1709 sg_start_req(Sg_request *srp, unsigned char *cmd) 1710 { 1711 int res; 1712 struct request *rq; 1713 struct scsi_request *req; 1714 Sg_fd *sfp = srp->parentfp; 1715 sg_io_hdr_t *hp = &srp->header; 1716 int dxfer_len = (int) hp->dxfer_len; 1717 int dxfer_dir = hp->dxfer_direction; 1718 unsigned int iov_count = hp->iovec_count; 1719 Sg_scatter_hold *req_schp = &srp->data; 1720 Sg_scatter_hold *rsv_schp = &sfp->reserve; 1721 struct request_queue *q = sfp->parentdp->device->request_queue; 1722 struct rq_map_data *md, map_data; 1723 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ; 1724 unsigned char *long_cmdp = NULL; 1725 1726 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 1727 "sg_start_req: dxfer_len=%d\n", 1728 dxfer_len)); 1729 1730 if (hp->cmd_len > BLK_MAX_CDB) { 1731 long_cmdp = kzalloc(hp->cmd_len, GFP_KERNEL); 1732 if (!long_cmdp) 1733 return -ENOMEM; 1734 } 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 blk_get_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 = blk_get_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 kfree(long_cmdp); 1751 return PTR_ERR(rq); 1752 } 1753 req = scsi_req(rq); 1754 1755 if (hp->cmd_len > BLK_MAX_CDB) 1756 req->cmd = long_cmdp; 1757 memcpy(req->cmd, cmd, hp->cmd_len); 1758 req->cmd_len = hp->cmd_len; 1759 1760 srp->rq = rq; 1761 rq->end_io_data = srp; 1762 req->retries = SG_DEFAULT_RETRIES; 1763 1764 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE)) 1765 return 0; 1766 1767 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO && 1768 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count && 1769 blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len)) 1770 md = NULL; 1771 else 1772 md = &map_data; 1773 1774 if (md) { 1775 mutex_lock(&sfp->f_mutex); 1776 if (dxfer_len <= rsv_schp->bufflen && 1777 !sfp->res_in_use) { 1778 sfp->res_in_use = 1; 1779 sg_link_reserve(sfp, srp, dxfer_len); 1780 } else if (hp->flags & SG_FLAG_MMAP_IO) { 1781 res = -EBUSY; /* sfp->res_in_use == 1 */ 1782 if (dxfer_len > rsv_schp->bufflen) 1783 res = -ENOMEM; 1784 mutex_unlock(&sfp->f_mutex); 1785 return res; 1786 } else { 1787 res = sg_build_indirect(req_schp, sfp, dxfer_len); 1788 if (res) { 1789 mutex_unlock(&sfp->f_mutex); 1790 return res; 1791 } 1792 } 1793 mutex_unlock(&sfp->f_mutex); 1794 1795 md->pages = req_schp->pages; 1796 md->page_order = req_schp->page_order; 1797 md->nr_entries = req_schp->k_use_sg; 1798 md->offset = 0; 1799 md->null_mapped = hp->dxferp ? 0 : 1; 1800 if (dxfer_dir == SG_DXFER_TO_FROM_DEV) 1801 md->from_user = 1; 1802 else 1803 md->from_user = 0; 1804 } 1805 1806 if (iov_count) { 1807 struct iovec *iov = NULL; 1808 struct iov_iter i; 1809 1810 res = import_iovec(rw, hp->dxferp, iov_count, 0, &iov, &i); 1811 if (res < 0) 1812 return res; 1813 1814 iov_iter_truncate(&i, hp->dxfer_len); 1815 if (!iov_iter_count(&i)) { 1816 kfree(iov); 1817 return -EINVAL; 1818 } 1819 1820 res = blk_rq_map_user_iov(q, rq, md, &i, GFP_ATOMIC); 1821 kfree(iov); 1822 } else 1823 res = blk_rq_map_user(q, rq, md, hp->dxferp, 1824 hp->dxfer_len, GFP_ATOMIC); 1825 1826 if (!res) { 1827 srp->bio = rq->bio; 1828 1829 if (!md) { 1830 req_schp->dio_in_use = 1; 1831 hp->info |= SG_INFO_DIRECT_IO; 1832 } 1833 } 1834 return res; 1835 } 1836 1837 static int 1838 sg_finish_rem_req(Sg_request *srp) 1839 { 1840 int ret = 0; 1841 1842 Sg_fd *sfp = srp->parentfp; 1843 Sg_scatter_hold *req_schp = &srp->data; 1844 1845 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 1846 "sg_finish_rem_req: res_used=%d\n", 1847 (int) srp->res_used)); 1848 if (srp->bio) 1849 ret = blk_rq_unmap_user(srp->bio); 1850 1851 if (srp->rq) { 1852 scsi_req_free_cmd(scsi_req(srp->rq)); 1853 blk_put_request(srp->rq); 1854 } 1855 1856 if (srp->res_used) 1857 sg_unlink_reserve(sfp, srp); 1858 else 1859 sg_remove_scat(sfp, req_schp); 1860 1861 return ret; 1862 } 1863 1864 static int 1865 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize) 1866 { 1867 int sg_bufflen = tablesize * sizeof(struct page *); 1868 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN; 1869 1870 schp->pages = kzalloc(sg_bufflen, gfp_flags); 1871 if (!schp->pages) 1872 return -ENOMEM; 1873 schp->sglist_len = sg_bufflen; 1874 return tablesize; /* number of scat_gath elements allocated */ 1875 } 1876 1877 static int 1878 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size) 1879 { 1880 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems; 1881 int sg_tablesize = sfp->parentdp->sg_tablesize; 1882 int blk_size = buff_size, order; 1883 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN | __GFP_ZERO; 1884 1885 if (blk_size < 0) 1886 return -EFAULT; 1887 if (0 == blk_size) 1888 ++blk_size; /* don't know why */ 1889 /* round request up to next highest SG_SECTOR_SZ byte boundary */ 1890 blk_size = ALIGN(blk_size, SG_SECTOR_SZ); 1891 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 1892 "sg_build_indirect: buff_size=%d, blk_size=%d\n", 1893 buff_size, blk_size)); 1894 1895 /* N.B. ret_sz carried into this block ... */ 1896 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize); 1897 if (mx_sc_elems < 0) 1898 return mx_sc_elems; /* most likely -ENOMEM */ 1899 1900 num = scatter_elem_sz; 1901 if (unlikely(num != scatter_elem_sz_prev)) { 1902 if (num < PAGE_SIZE) { 1903 scatter_elem_sz = PAGE_SIZE; 1904 scatter_elem_sz_prev = PAGE_SIZE; 1905 } else 1906 scatter_elem_sz_prev = num; 1907 } 1908 1909 order = get_order(num); 1910 retry: 1911 ret_sz = 1 << (PAGE_SHIFT + order); 1912 1913 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems; 1914 k++, rem_sz -= ret_sz) { 1915 1916 num = (rem_sz > scatter_elem_sz_prev) ? 1917 scatter_elem_sz_prev : rem_sz; 1918 1919 schp->pages[k] = alloc_pages(gfp_mask, order); 1920 if (!schp->pages[k]) 1921 goto out; 1922 1923 if (num == scatter_elem_sz_prev) { 1924 if (unlikely(ret_sz > scatter_elem_sz_prev)) { 1925 scatter_elem_sz = ret_sz; 1926 scatter_elem_sz_prev = ret_sz; 1927 } 1928 } 1929 1930 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp, 1931 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n", 1932 k, num, ret_sz)); 1933 } /* end of for loop */ 1934 1935 schp->page_order = order; 1936 schp->k_use_sg = k; 1937 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp, 1938 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n", 1939 k, rem_sz)); 1940 1941 schp->bufflen = blk_size; 1942 if (rem_sz > 0) /* must have failed */ 1943 return -ENOMEM; 1944 return 0; 1945 out: 1946 for (i = 0; i < k; i++) 1947 __free_pages(schp->pages[i], order); 1948 1949 if (--order >= 0) 1950 goto retry; 1951 1952 return -ENOMEM; 1953 } 1954 1955 static void 1956 sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp) 1957 { 1958 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 1959 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg)); 1960 if (schp->pages && schp->sglist_len > 0) { 1961 if (!schp->dio_in_use) { 1962 int k; 1963 1964 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) { 1965 SCSI_LOG_TIMEOUT(5, 1966 sg_printk(KERN_INFO, sfp->parentdp, 1967 "sg_remove_scat: k=%d, pg=0x%p\n", 1968 k, schp->pages[k])); 1969 __free_pages(schp->pages[k], schp->page_order); 1970 } 1971 1972 kfree(schp->pages); 1973 } 1974 } 1975 memset(schp, 0, sizeof (*schp)); 1976 } 1977 1978 static int 1979 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer) 1980 { 1981 Sg_scatter_hold *schp = &srp->data; 1982 int k, num; 1983 1984 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp, 1985 "sg_read_oxfer: num_read_xfer=%d\n", 1986 num_read_xfer)); 1987 if ((!outp) || (num_read_xfer <= 0)) 1988 return 0; 1989 1990 num = 1 << (PAGE_SHIFT + schp->page_order); 1991 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) { 1992 if (num > num_read_xfer) { 1993 if (copy_to_user(outp, page_address(schp->pages[k]), 1994 num_read_xfer)) 1995 return -EFAULT; 1996 break; 1997 } else { 1998 if (copy_to_user(outp, page_address(schp->pages[k]), 1999 num)) 2000 return -EFAULT; 2001 num_read_xfer -= num; 2002 if (num_read_xfer <= 0) 2003 break; 2004 outp += num; 2005 } 2006 } 2007 2008 return 0; 2009 } 2010 2011 static void 2012 sg_build_reserve(Sg_fd * sfp, int req_size) 2013 { 2014 Sg_scatter_hold *schp = &sfp->reserve; 2015 2016 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 2017 "sg_build_reserve: req_size=%d\n", req_size)); 2018 do { 2019 if (req_size < PAGE_SIZE) 2020 req_size = PAGE_SIZE; 2021 if (0 == sg_build_indirect(schp, sfp, req_size)) 2022 return; 2023 else 2024 sg_remove_scat(sfp, schp); 2025 req_size >>= 1; /* divide by 2 */ 2026 } while (req_size > (PAGE_SIZE / 2)); 2027 } 2028 2029 static void 2030 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size) 2031 { 2032 Sg_scatter_hold *req_schp = &srp->data; 2033 Sg_scatter_hold *rsv_schp = &sfp->reserve; 2034 int k, num, rem; 2035 2036 srp->res_used = 1; 2037 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 2038 "sg_link_reserve: size=%d\n", size)); 2039 rem = size; 2040 2041 num = 1 << (PAGE_SHIFT + rsv_schp->page_order); 2042 for (k = 0; k < rsv_schp->k_use_sg; k++) { 2043 if (rem <= num) { 2044 req_schp->k_use_sg = k + 1; 2045 req_schp->sglist_len = rsv_schp->sglist_len; 2046 req_schp->pages = rsv_schp->pages; 2047 2048 req_schp->bufflen = size; 2049 req_schp->page_order = rsv_schp->page_order; 2050 break; 2051 } else 2052 rem -= num; 2053 } 2054 2055 if (k >= rsv_schp->k_use_sg) 2056 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp, 2057 "sg_link_reserve: BAD size\n")); 2058 } 2059 2060 static void 2061 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp) 2062 { 2063 Sg_scatter_hold *req_schp = &srp->data; 2064 2065 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp, 2066 "sg_unlink_reserve: req->k_use_sg=%d\n", 2067 (int) req_schp->k_use_sg)); 2068 req_schp->k_use_sg = 0; 2069 req_schp->bufflen = 0; 2070 req_schp->pages = NULL; 2071 req_schp->page_order = 0; 2072 req_schp->sglist_len = 0; 2073 srp->res_used = 0; 2074 /* Called without mutex lock to avoid deadlock */ 2075 sfp->res_in_use = 0; 2076 } 2077 2078 static Sg_request * 2079 sg_get_rq_mark(Sg_fd * sfp, int pack_id) 2080 { 2081 Sg_request *resp; 2082 unsigned long iflags; 2083 2084 write_lock_irqsave(&sfp->rq_list_lock, iflags); 2085 list_for_each_entry(resp, &sfp->rq_list, entry) { 2086 /* look for requests that are ready + not SG_IO owned */ 2087 if ((1 == resp->done) && (!resp->sg_io_owned) && 2088 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) { 2089 resp->done = 2; /* guard against other readers */ 2090 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2091 return resp; 2092 } 2093 } 2094 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2095 return NULL; 2096 } 2097 2098 /* always adds to end of list */ 2099 static Sg_request * 2100 sg_add_request(Sg_fd * sfp) 2101 { 2102 int k; 2103 unsigned long iflags; 2104 Sg_request *rp = sfp->req_arr; 2105 2106 write_lock_irqsave(&sfp->rq_list_lock, iflags); 2107 if (!list_empty(&sfp->rq_list)) { 2108 if (!sfp->cmd_q) 2109 goto out_unlock; 2110 2111 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) { 2112 if (!rp->parentfp) 2113 break; 2114 } 2115 if (k >= SG_MAX_QUEUE) 2116 goto out_unlock; 2117 } 2118 memset(rp, 0, sizeof (Sg_request)); 2119 rp->parentfp = sfp; 2120 rp->header.duration = jiffies_to_msecs(jiffies); 2121 list_add_tail(&rp->entry, &sfp->rq_list); 2122 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2123 return rp; 2124 out_unlock: 2125 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2126 return NULL; 2127 } 2128 2129 /* Return of 1 for found; 0 for not found */ 2130 static int 2131 sg_remove_request(Sg_fd * sfp, Sg_request * srp) 2132 { 2133 unsigned long iflags; 2134 int res = 0; 2135 2136 if (!sfp || !srp || list_empty(&sfp->rq_list)) 2137 return res; 2138 write_lock_irqsave(&sfp->rq_list_lock, iflags); 2139 if (!list_empty(&srp->entry)) { 2140 list_del(&srp->entry); 2141 srp->parentfp = NULL; 2142 res = 1; 2143 } 2144 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2145 return res; 2146 } 2147 2148 static Sg_fd * 2149 sg_add_sfp(Sg_device * sdp) 2150 { 2151 Sg_fd *sfp; 2152 unsigned long iflags; 2153 int bufflen; 2154 2155 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN); 2156 if (!sfp) 2157 return ERR_PTR(-ENOMEM); 2158 2159 init_waitqueue_head(&sfp->read_wait); 2160 rwlock_init(&sfp->rq_list_lock); 2161 INIT_LIST_HEAD(&sfp->rq_list); 2162 kref_init(&sfp->f_ref); 2163 mutex_init(&sfp->f_mutex); 2164 sfp->timeout = SG_DEFAULT_TIMEOUT; 2165 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER; 2166 sfp->force_packid = SG_DEF_FORCE_PACK_ID; 2167 sfp->cmd_q = SG_DEF_COMMAND_Q; 2168 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN; 2169 sfp->parentdp = sdp; 2170 write_lock_irqsave(&sdp->sfd_lock, iflags); 2171 if (atomic_read(&sdp->detaching)) { 2172 write_unlock_irqrestore(&sdp->sfd_lock, iflags); 2173 kfree(sfp); 2174 return ERR_PTR(-ENODEV); 2175 } 2176 list_add_tail(&sfp->sfd_siblings, &sdp->sfds); 2177 write_unlock_irqrestore(&sdp->sfd_lock, iflags); 2178 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 2179 "sg_add_sfp: sfp=0x%p\n", sfp)); 2180 if (unlikely(sg_big_buff != def_reserved_size)) 2181 sg_big_buff = def_reserved_size; 2182 2183 bufflen = min_t(int, sg_big_buff, 2184 max_sectors_bytes(sdp->device->request_queue)); 2185 sg_build_reserve(sfp, bufflen); 2186 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 2187 "sg_add_sfp: bufflen=%d, k_use_sg=%d\n", 2188 sfp->reserve.bufflen, 2189 sfp->reserve.k_use_sg)); 2190 2191 kref_get(&sdp->d_ref); 2192 __module_get(THIS_MODULE); 2193 return sfp; 2194 } 2195 2196 static void 2197 sg_remove_sfp_usercontext(struct work_struct *work) 2198 { 2199 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work); 2200 struct sg_device *sdp = sfp->parentdp; 2201 Sg_request *srp; 2202 unsigned long iflags; 2203 2204 /* Cleanup any responses which were never read(). */ 2205 write_lock_irqsave(&sfp->rq_list_lock, iflags); 2206 while (!list_empty(&sfp->rq_list)) { 2207 srp = list_first_entry(&sfp->rq_list, Sg_request, entry); 2208 sg_finish_rem_req(srp); 2209 list_del(&srp->entry); 2210 srp->parentfp = NULL; 2211 } 2212 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2213 2214 if (sfp->reserve.bufflen > 0) { 2215 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp, 2216 "sg_remove_sfp: bufflen=%d, k_use_sg=%d\n", 2217 (int) sfp->reserve.bufflen, 2218 (int) sfp->reserve.k_use_sg)); 2219 sg_remove_scat(sfp, &sfp->reserve); 2220 } 2221 2222 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp, 2223 "sg_remove_sfp: sfp=0x%p\n", sfp)); 2224 kfree(sfp); 2225 2226 scsi_device_put(sdp->device); 2227 kref_put(&sdp->d_ref, sg_device_destroy); 2228 module_put(THIS_MODULE); 2229 } 2230 2231 static void 2232 sg_remove_sfp(struct kref *kref) 2233 { 2234 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref); 2235 struct sg_device *sdp = sfp->parentdp; 2236 unsigned long iflags; 2237 2238 write_lock_irqsave(&sdp->sfd_lock, iflags); 2239 list_del(&sfp->sfd_siblings); 2240 write_unlock_irqrestore(&sdp->sfd_lock, iflags); 2241 2242 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext); 2243 schedule_work(&sfp->ew.work); 2244 } 2245 2246 #ifdef CONFIG_SCSI_PROC_FS 2247 static int 2248 sg_idr_max_id(int id, void *p, void *data) 2249 { 2250 int *k = data; 2251 2252 if (*k < id) 2253 *k = id; 2254 2255 return 0; 2256 } 2257 2258 static int 2259 sg_last_dev(void) 2260 { 2261 int k = -1; 2262 unsigned long iflags; 2263 2264 read_lock_irqsave(&sg_index_lock, iflags); 2265 idr_for_each(&sg_index_idr, sg_idr_max_id, &k); 2266 read_unlock_irqrestore(&sg_index_lock, iflags); 2267 return k + 1; /* origin 1 */ 2268 } 2269 #endif 2270 2271 /* must be called with sg_index_lock held */ 2272 static Sg_device *sg_lookup_dev(int dev) 2273 { 2274 return idr_find(&sg_index_idr, dev); 2275 } 2276 2277 static Sg_device * 2278 sg_get_dev(int dev) 2279 { 2280 struct sg_device *sdp; 2281 unsigned long flags; 2282 2283 read_lock_irqsave(&sg_index_lock, flags); 2284 sdp = sg_lookup_dev(dev); 2285 if (!sdp) 2286 sdp = ERR_PTR(-ENXIO); 2287 else if (atomic_read(&sdp->detaching)) { 2288 /* If sdp->detaching, then the refcount may already be 0, in 2289 * which case it would be a bug to do kref_get(). 2290 */ 2291 sdp = ERR_PTR(-ENODEV); 2292 } else 2293 kref_get(&sdp->d_ref); 2294 read_unlock_irqrestore(&sg_index_lock, flags); 2295 2296 return sdp; 2297 } 2298 2299 #ifdef CONFIG_SCSI_PROC_FS 2300 static int sg_proc_seq_show_int(struct seq_file *s, void *v); 2301 2302 static int sg_proc_single_open_adio(struct inode *inode, struct file *file); 2303 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer, 2304 size_t count, loff_t *off); 2305 static const struct proc_ops adio_proc_ops = { 2306 .proc_open = sg_proc_single_open_adio, 2307 .proc_read = seq_read, 2308 .proc_lseek = seq_lseek, 2309 .proc_write = sg_proc_write_adio, 2310 .proc_release = single_release, 2311 }; 2312 2313 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file); 2314 static ssize_t sg_proc_write_dressz(struct file *filp, 2315 const char __user *buffer, size_t count, loff_t *off); 2316 static const struct proc_ops dressz_proc_ops = { 2317 .proc_open = sg_proc_single_open_dressz, 2318 .proc_read = seq_read, 2319 .proc_lseek = seq_lseek, 2320 .proc_write = sg_proc_write_dressz, 2321 .proc_release = single_release, 2322 }; 2323 2324 static int sg_proc_seq_show_version(struct seq_file *s, void *v); 2325 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v); 2326 static int sg_proc_seq_show_dev(struct seq_file *s, void *v); 2327 static void * dev_seq_start(struct seq_file *s, loff_t *pos); 2328 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos); 2329 static void dev_seq_stop(struct seq_file *s, void *v); 2330 static const struct seq_operations dev_seq_ops = { 2331 .start = dev_seq_start, 2332 .next = dev_seq_next, 2333 .stop = dev_seq_stop, 2334 .show = sg_proc_seq_show_dev, 2335 }; 2336 2337 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v); 2338 static const struct seq_operations devstrs_seq_ops = { 2339 .start = dev_seq_start, 2340 .next = dev_seq_next, 2341 .stop = dev_seq_stop, 2342 .show = sg_proc_seq_show_devstrs, 2343 }; 2344 2345 static int sg_proc_seq_show_debug(struct seq_file *s, void *v); 2346 static const struct seq_operations debug_seq_ops = { 2347 .start = dev_seq_start, 2348 .next = dev_seq_next, 2349 .stop = dev_seq_stop, 2350 .show = sg_proc_seq_show_debug, 2351 }; 2352 2353 static int 2354 sg_proc_init(void) 2355 { 2356 struct proc_dir_entry *p; 2357 2358 p = proc_mkdir("scsi/sg", NULL); 2359 if (!p) 2360 return 1; 2361 2362 proc_create("allow_dio", S_IRUGO | S_IWUSR, p, &adio_proc_ops); 2363 proc_create_seq("debug", S_IRUGO, p, &debug_seq_ops); 2364 proc_create("def_reserved_size", S_IRUGO | S_IWUSR, p, &dressz_proc_ops); 2365 proc_create_single("device_hdr", S_IRUGO, p, sg_proc_seq_show_devhdr); 2366 proc_create_seq("devices", S_IRUGO, p, &dev_seq_ops); 2367 proc_create_seq("device_strs", S_IRUGO, p, &devstrs_seq_ops); 2368 proc_create_single("version", S_IRUGO, p, sg_proc_seq_show_version); 2369 return 0; 2370 } 2371 2372 2373 static int sg_proc_seq_show_int(struct seq_file *s, void *v) 2374 { 2375 seq_printf(s, "%d\n", *((int *)s->private)); 2376 return 0; 2377 } 2378 2379 static int sg_proc_single_open_adio(struct inode *inode, struct file *file) 2380 { 2381 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio); 2382 } 2383 2384 static ssize_t 2385 sg_proc_write_adio(struct file *filp, const char __user *buffer, 2386 size_t count, loff_t *off) 2387 { 2388 int err; 2389 unsigned long num; 2390 2391 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) 2392 return -EACCES; 2393 err = kstrtoul_from_user(buffer, count, 0, &num); 2394 if (err) 2395 return err; 2396 sg_allow_dio = num ? 1 : 0; 2397 return count; 2398 } 2399 2400 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file) 2401 { 2402 return single_open(file, sg_proc_seq_show_int, &sg_big_buff); 2403 } 2404 2405 static ssize_t 2406 sg_proc_write_dressz(struct file *filp, const char __user *buffer, 2407 size_t count, loff_t *off) 2408 { 2409 int err; 2410 unsigned long k = ULONG_MAX; 2411 2412 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) 2413 return -EACCES; 2414 2415 err = kstrtoul_from_user(buffer, count, 0, &k); 2416 if (err) 2417 return err; 2418 if (k <= 1048576) { /* limit "big buff" to 1 MB */ 2419 sg_big_buff = k; 2420 return count; 2421 } 2422 return -ERANGE; 2423 } 2424 2425 static int sg_proc_seq_show_version(struct seq_file *s, void *v) 2426 { 2427 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR, 2428 sg_version_date); 2429 return 0; 2430 } 2431 2432 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v) 2433 { 2434 seq_puts(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n"); 2435 return 0; 2436 } 2437 2438 struct sg_proc_deviter { 2439 loff_t index; 2440 size_t max; 2441 }; 2442 2443 static void * dev_seq_start(struct seq_file *s, loff_t *pos) 2444 { 2445 struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL); 2446 2447 s->private = it; 2448 if (! it) 2449 return NULL; 2450 2451 it->index = *pos; 2452 it->max = sg_last_dev(); 2453 if (it->index >= it->max) 2454 return NULL; 2455 return it; 2456 } 2457 2458 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos) 2459 { 2460 struct sg_proc_deviter * it = s->private; 2461 2462 *pos = ++it->index; 2463 return (it->index < it->max) ? it : NULL; 2464 } 2465 2466 static void dev_seq_stop(struct seq_file *s, void *v) 2467 { 2468 kfree(s->private); 2469 } 2470 2471 static int sg_proc_seq_show_dev(struct seq_file *s, void *v) 2472 { 2473 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v; 2474 Sg_device *sdp; 2475 struct scsi_device *scsidp; 2476 unsigned long iflags; 2477 2478 read_lock_irqsave(&sg_index_lock, iflags); 2479 sdp = it ? sg_lookup_dev(it->index) : NULL; 2480 if ((NULL == sdp) || (NULL == sdp->device) || 2481 (atomic_read(&sdp->detaching))) 2482 seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n"); 2483 else { 2484 scsidp = sdp->device; 2485 seq_printf(s, "%d\t%d\t%d\t%llu\t%d\t%d\t%d\t%d\t%d\n", 2486 scsidp->host->host_no, scsidp->channel, 2487 scsidp->id, scsidp->lun, (int) scsidp->type, 2488 1, 2489 (int) scsidp->queue_depth, 2490 (int) scsi_device_busy(scsidp), 2491 (int) scsi_device_online(scsidp)); 2492 } 2493 read_unlock_irqrestore(&sg_index_lock, iflags); 2494 return 0; 2495 } 2496 2497 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v) 2498 { 2499 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v; 2500 Sg_device *sdp; 2501 struct scsi_device *scsidp; 2502 unsigned long iflags; 2503 2504 read_lock_irqsave(&sg_index_lock, iflags); 2505 sdp = it ? sg_lookup_dev(it->index) : NULL; 2506 scsidp = sdp ? sdp->device : NULL; 2507 if (sdp && scsidp && (!atomic_read(&sdp->detaching))) 2508 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n", 2509 scsidp->vendor, scsidp->model, scsidp->rev); 2510 else 2511 seq_puts(s, "<no active device>\n"); 2512 read_unlock_irqrestore(&sg_index_lock, iflags); 2513 return 0; 2514 } 2515 2516 /* must be called while holding sg_index_lock */ 2517 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp) 2518 { 2519 int k, new_interface, blen, usg; 2520 Sg_request *srp; 2521 Sg_fd *fp; 2522 const sg_io_hdr_t *hp; 2523 const char * cp; 2524 unsigned int ms; 2525 2526 k = 0; 2527 list_for_each_entry(fp, &sdp->sfds, sfd_siblings) { 2528 k++; 2529 read_lock(&fp->rq_list_lock); /* irqs already disabled */ 2530 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d " 2531 "(res)sgat=%d low_dma=%d\n", k, 2532 jiffies_to_msecs(fp->timeout), 2533 fp->reserve.bufflen, 2534 (int) fp->reserve.k_use_sg, 0); 2535 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n", 2536 (int) fp->cmd_q, (int) fp->force_packid, 2537 (int) fp->keep_orphan); 2538 list_for_each_entry(srp, &fp->rq_list, entry) { 2539 hp = &srp->header; 2540 new_interface = (hp->interface_id == '\0') ? 0 : 1; 2541 if (srp->res_used) { 2542 if (new_interface && 2543 (SG_FLAG_MMAP_IO & hp->flags)) 2544 cp = " mmap>> "; 2545 else 2546 cp = " rb>> "; 2547 } else { 2548 if (SG_INFO_DIRECT_IO_MASK & hp->info) 2549 cp = " dio>> "; 2550 else 2551 cp = " "; 2552 } 2553 seq_puts(s, cp); 2554 blen = srp->data.bufflen; 2555 usg = srp->data.k_use_sg; 2556 seq_puts(s, srp->done ? 2557 ((1 == srp->done) ? "rcv:" : "fin:") 2558 : "act:"); 2559 seq_printf(s, " id=%d blen=%d", 2560 srp->header.pack_id, blen); 2561 if (srp->done) 2562 seq_printf(s, " dur=%d", hp->duration); 2563 else { 2564 ms = jiffies_to_msecs(jiffies); 2565 seq_printf(s, " t_o/elap=%d/%d", 2566 (new_interface ? hp->timeout : 2567 jiffies_to_msecs(fp->timeout)), 2568 (ms > hp->duration ? ms - hp->duration : 0)); 2569 } 2570 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg, 2571 (int) srp->data.cmd_opcode); 2572 } 2573 if (list_empty(&fp->rq_list)) 2574 seq_puts(s, " No requests active\n"); 2575 read_unlock(&fp->rq_list_lock); 2576 } 2577 } 2578 2579 static int sg_proc_seq_show_debug(struct seq_file *s, void *v) 2580 { 2581 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v; 2582 Sg_device *sdp; 2583 unsigned long iflags; 2584 2585 if (it && (0 == it->index)) 2586 seq_printf(s, "max_active_device=%d def_reserved_size=%d\n", 2587 (int)it->max, sg_big_buff); 2588 2589 read_lock_irqsave(&sg_index_lock, iflags); 2590 sdp = it ? sg_lookup_dev(it->index) : NULL; 2591 if (NULL == sdp) 2592 goto skip; 2593 read_lock(&sdp->sfd_lock); 2594 if (!list_empty(&sdp->sfds)) { 2595 seq_printf(s, " >>> device=%s ", sdp->name); 2596 if (atomic_read(&sdp->detaching)) 2597 seq_puts(s, "detaching pending close "); 2598 else if (sdp->device) { 2599 struct scsi_device *scsidp = sdp->device; 2600 2601 seq_printf(s, "%d:%d:%d:%llu em=%d", 2602 scsidp->host->host_no, 2603 scsidp->channel, scsidp->id, 2604 scsidp->lun, 2605 scsidp->host->hostt->emulated); 2606 } 2607 seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n", 2608 sdp->sg_tablesize, sdp->exclude, sdp->open_cnt); 2609 sg_proc_debug_helper(s, sdp); 2610 } 2611 read_unlock(&sdp->sfd_lock); 2612 skip: 2613 read_unlock_irqrestore(&sg_index_lock, iflags); 2614 return 0; 2615 } 2616 2617 #endif /* CONFIG_SCSI_PROC_FS */ 2618 2619 module_init(init_sg); 2620 module_exit(exit_sg); 2621