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 *, struct class_interface *); 100 static void sg_remove_device(struct device *, struct class_interface *); 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 void 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); 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 if (uaccess_kernel()) { 232 pr_err_once("%s: process %d (%s) called from kernel context, this is not allowed.\n", 233 caller, task_tgid_vnr(current), current->comm); 234 return -EACCES; 235 } 236 return 0; 237 } 238 239 static int sg_allow_access(struct file *filp, unsigned char *cmd) 240 { 241 struct sg_fd *sfp = filp->private_data; 242 243 if (sfp->parentdp->device->type == TYPE_SCANNER) 244 return 0; 245 if (!scsi_cmd_allowed(cmd, filp->f_mode)) 246 return -EPERM; 247 return 0; 248 } 249 250 static int 251 open_wait(Sg_device *sdp, int flags) 252 { 253 int retval = 0; 254 255 if (flags & O_EXCL) { 256 while (sdp->open_cnt > 0) { 257 mutex_unlock(&sdp->open_rel_lock); 258 retval = wait_event_interruptible(sdp->open_wait, 259 (atomic_read(&sdp->detaching) || 260 !sdp->open_cnt)); 261 mutex_lock(&sdp->open_rel_lock); 262 263 if (retval) /* -ERESTARTSYS */ 264 return retval; 265 if (atomic_read(&sdp->detaching)) 266 return -ENODEV; 267 } 268 } else { 269 while (sdp->exclude) { 270 mutex_unlock(&sdp->open_rel_lock); 271 retval = wait_event_interruptible(sdp->open_wait, 272 (atomic_read(&sdp->detaching) || 273 !sdp->exclude)); 274 mutex_lock(&sdp->open_rel_lock); 275 276 if (retval) /* -ERESTARTSYS */ 277 return retval; 278 if (atomic_read(&sdp->detaching)) 279 return -ENODEV; 280 } 281 } 282 283 return retval; 284 } 285 286 /* Returns 0 on success, else a negated errno value */ 287 static int 288 sg_open(struct inode *inode, struct file *filp) 289 { 290 int dev = iminor(inode); 291 int flags = filp->f_flags; 292 struct request_queue *q; 293 Sg_device *sdp; 294 Sg_fd *sfp; 295 int retval; 296 297 nonseekable_open(inode, filp); 298 if ((flags & O_EXCL) && (O_RDONLY == (flags & O_ACCMODE))) 299 return -EPERM; /* Can't lock it with read only access */ 300 sdp = sg_get_dev(dev); 301 if (IS_ERR(sdp)) 302 return PTR_ERR(sdp); 303 304 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 305 "sg_open: flags=0x%x\n", flags)); 306 307 /* This driver's module count bumped by fops_get in <linux/fs.h> */ 308 /* Prevent the device driver from vanishing while we sleep */ 309 retval = scsi_device_get(sdp->device); 310 if (retval) 311 goto sg_put; 312 313 retval = scsi_autopm_get_device(sdp->device); 314 if (retval) 315 goto sdp_put; 316 317 /* scsi_block_when_processing_errors() may block so bypass 318 * check if O_NONBLOCK. Permits SCSI commands to be issued 319 * during error recovery. Tread carefully. */ 320 if (!((flags & O_NONBLOCK) || 321 scsi_block_when_processing_errors(sdp->device))) { 322 retval = -ENXIO; 323 /* we are in error recovery for this device */ 324 goto error_out; 325 } 326 327 mutex_lock(&sdp->open_rel_lock); 328 if (flags & O_NONBLOCK) { 329 if (flags & O_EXCL) { 330 if (sdp->open_cnt > 0) { 331 retval = -EBUSY; 332 goto error_mutex_locked; 333 } 334 } else { 335 if (sdp->exclude) { 336 retval = -EBUSY; 337 goto error_mutex_locked; 338 } 339 } 340 } else { 341 retval = open_wait(sdp, flags); 342 if (retval) /* -ERESTARTSYS or -ENODEV */ 343 goto error_mutex_locked; 344 } 345 346 /* N.B. at this point we are holding the open_rel_lock */ 347 if (flags & O_EXCL) 348 sdp->exclude = true; 349 350 if (sdp->open_cnt < 1) { /* no existing opens */ 351 sdp->sgdebug = 0; 352 q = sdp->device->request_queue; 353 sdp->sg_tablesize = queue_max_segments(q); 354 } 355 sfp = sg_add_sfp(sdp); 356 if (IS_ERR(sfp)) { 357 retval = PTR_ERR(sfp); 358 goto out_undo; 359 } 360 361 filp->private_data = sfp; 362 sdp->open_cnt++; 363 mutex_unlock(&sdp->open_rel_lock); 364 365 retval = 0; 366 sg_put: 367 kref_put(&sdp->d_ref, sg_device_destroy); 368 return retval; 369 370 out_undo: 371 if (flags & O_EXCL) { 372 sdp->exclude = false; /* undo if error */ 373 wake_up_interruptible(&sdp->open_wait); 374 } 375 error_mutex_locked: 376 mutex_unlock(&sdp->open_rel_lock); 377 error_out: 378 scsi_autopm_put_device(sdp->device); 379 sdp_put: 380 scsi_device_put(sdp->device); 381 goto sg_put; 382 } 383 384 /* Release resources associated with a successful sg_open() 385 * Returns 0 on success, else a negated errno value */ 386 static int 387 sg_release(struct inode *inode, struct file *filp) 388 { 389 Sg_device *sdp; 390 Sg_fd *sfp; 391 392 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 393 return -ENXIO; 394 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, "sg_release\n")); 395 396 mutex_lock(&sdp->open_rel_lock); 397 scsi_autopm_put_device(sdp->device); 398 kref_put(&sfp->f_ref, sg_remove_sfp); 399 sdp->open_cnt--; 400 401 /* possibly many open()s waiting on exlude clearing, start many; 402 * only open(O_EXCL)s wait on 0==open_cnt so only start one */ 403 if (sdp->exclude) { 404 sdp->exclude = false; 405 wake_up_interruptible_all(&sdp->open_wait); 406 } else if (0 == sdp->open_cnt) { 407 wake_up_interruptible(&sdp->open_wait); 408 } 409 mutex_unlock(&sdp->open_rel_lock); 410 return 0; 411 } 412 413 static int get_sg_io_pack_id(int *pack_id, void __user *buf, size_t count) 414 { 415 struct sg_header __user *old_hdr = buf; 416 int reply_len; 417 418 if (count >= SZ_SG_HEADER) { 419 /* negative reply_len means v3 format, otherwise v1/v2 */ 420 if (get_user(reply_len, &old_hdr->reply_len)) 421 return -EFAULT; 422 423 if (reply_len >= 0) 424 return get_user(*pack_id, &old_hdr->pack_id); 425 426 if (in_compat_syscall() && 427 count >= sizeof(struct compat_sg_io_hdr)) { 428 struct compat_sg_io_hdr __user *hp = buf; 429 430 return get_user(*pack_id, &hp->pack_id); 431 } 432 433 if (count >= sizeof(struct sg_io_hdr)) { 434 struct sg_io_hdr __user *hp = buf; 435 436 return get_user(*pack_id, &hp->pack_id); 437 } 438 } 439 440 /* no valid header was passed, so ignore the pack_id */ 441 *pack_id = -1; 442 return 0; 443 } 444 445 static ssize_t 446 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos) 447 { 448 Sg_device *sdp; 449 Sg_fd *sfp; 450 Sg_request *srp; 451 int req_pack_id = -1; 452 sg_io_hdr_t *hp; 453 struct sg_header *old_hdr; 454 int retval; 455 456 /* 457 * This could cause a response to be stranded. Close the associated 458 * file descriptor to free up any resources being held. 459 */ 460 retval = sg_check_file_access(filp, __func__); 461 if (retval) 462 return retval; 463 464 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 465 return -ENXIO; 466 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 467 "sg_read: count=%d\n", (int) count)); 468 469 if (sfp->force_packid) 470 retval = get_sg_io_pack_id(&req_pack_id, buf, count); 471 if (retval) 472 return retval; 473 474 srp = sg_get_rq_mark(sfp, req_pack_id); 475 if (!srp) { /* now wait on packet to arrive */ 476 if (atomic_read(&sdp->detaching)) 477 return -ENODEV; 478 if (filp->f_flags & O_NONBLOCK) 479 return -EAGAIN; 480 retval = wait_event_interruptible(sfp->read_wait, 481 (atomic_read(&sdp->detaching) || 482 (srp = sg_get_rq_mark(sfp, req_pack_id)))); 483 if (atomic_read(&sdp->detaching)) 484 return -ENODEV; 485 if (retval) 486 /* -ERESTARTSYS as signal hit process */ 487 return retval; 488 } 489 if (srp->header.interface_id != '\0') 490 return sg_new_read(sfp, buf, count, srp); 491 492 hp = &srp->header; 493 old_hdr = kzalloc(SZ_SG_HEADER, GFP_KERNEL); 494 if (!old_hdr) 495 return -ENOMEM; 496 497 old_hdr->reply_len = (int) hp->timeout; 498 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */ 499 old_hdr->pack_id = hp->pack_id; 500 old_hdr->twelve_byte = 501 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0; 502 old_hdr->target_status = hp->masked_status; 503 old_hdr->host_status = hp->host_status; 504 old_hdr->driver_status = hp->driver_status; 505 if ((CHECK_CONDITION & hp->masked_status) || 506 (srp->sense_b[0] & 0x70) == 0x70) { 507 old_hdr->driver_status = DRIVER_SENSE; 508 memcpy(old_hdr->sense_buffer, srp->sense_b, 509 sizeof (old_hdr->sense_buffer)); 510 } 511 switch (hp->host_status) { 512 /* This setup of 'result' is for backward compatibility and is best 513 ignored by the user who should use target, host + driver status */ 514 case DID_OK: 515 case DID_PASSTHROUGH: 516 case DID_SOFT_ERROR: 517 old_hdr->result = 0; 518 break; 519 case DID_NO_CONNECT: 520 case DID_BUS_BUSY: 521 case DID_TIME_OUT: 522 old_hdr->result = EBUSY; 523 break; 524 case DID_BAD_TARGET: 525 case DID_ABORT: 526 case DID_PARITY: 527 case DID_RESET: 528 case DID_BAD_INTR: 529 old_hdr->result = EIO; 530 break; 531 case DID_ERROR: 532 old_hdr->result = (srp->sense_b[0] == 0 && 533 hp->masked_status == GOOD) ? 0 : EIO; 534 break; 535 default: 536 old_hdr->result = EIO; 537 break; 538 } 539 540 /* Now copy the result back to the user buffer. */ 541 if (count >= SZ_SG_HEADER) { 542 if (copy_to_user(buf, old_hdr, SZ_SG_HEADER)) { 543 retval = -EFAULT; 544 goto free_old_hdr; 545 } 546 buf += SZ_SG_HEADER; 547 if (count > old_hdr->reply_len) 548 count = old_hdr->reply_len; 549 if (count > SZ_SG_HEADER) { 550 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) { 551 retval = -EFAULT; 552 goto free_old_hdr; 553 } 554 } 555 } else 556 count = (old_hdr->result == 0) ? 0 : -EIO; 557 sg_finish_rem_req(srp); 558 sg_remove_request(sfp, srp); 559 retval = count; 560 free_old_hdr: 561 kfree(old_hdr); 562 return retval; 563 } 564 565 static ssize_t 566 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp) 567 { 568 sg_io_hdr_t *hp = &srp->header; 569 int err = 0, err2; 570 int len; 571 572 if (in_compat_syscall()) { 573 if (count < sizeof(struct compat_sg_io_hdr)) { 574 err = -EINVAL; 575 goto err_out; 576 } 577 } else if (count < SZ_SG_IO_HDR) { 578 err = -EINVAL; 579 goto err_out; 580 } 581 hp->sb_len_wr = 0; 582 if ((hp->mx_sb_len > 0) && hp->sbp) { 583 if ((CHECK_CONDITION & hp->masked_status) || 584 (srp->sense_b[0] & 0x70) == 0x70) { 585 int sb_len = SCSI_SENSE_BUFFERSIZE; 586 sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len; 587 len = 8 + (int) srp->sense_b[7]; /* Additional sense length field */ 588 len = (len > sb_len) ? sb_len : len; 589 if (copy_to_user(hp->sbp, srp->sense_b, len)) { 590 err = -EFAULT; 591 goto err_out; 592 } 593 hp->driver_status = DRIVER_SENSE; 594 hp->sb_len_wr = len; 595 } 596 } 597 if (hp->masked_status || hp->host_status || hp->driver_status) 598 hp->info |= SG_INFO_CHECK; 599 err = put_sg_io_hdr(hp, buf); 600 err_out: 601 err2 = sg_finish_rem_req(srp); 602 sg_remove_request(sfp, srp); 603 return err ? : err2 ? : count; 604 } 605 606 static ssize_t 607 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos) 608 { 609 int mxsize, cmd_size, k; 610 int input_size, blocking; 611 unsigned char opcode; 612 Sg_device *sdp; 613 Sg_fd *sfp; 614 Sg_request *srp; 615 struct sg_header old_hdr; 616 sg_io_hdr_t *hp; 617 unsigned char cmnd[SG_MAX_CDB_SIZE]; 618 int retval; 619 620 retval = sg_check_file_access(filp, __func__); 621 if (retval) 622 return retval; 623 624 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 625 return -ENXIO; 626 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 627 "sg_write: count=%d\n", (int) count)); 628 if (atomic_read(&sdp->detaching)) 629 return -ENODEV; 630 if (!((filp->f_flags & O_NONBLOCK) || 631 scsi_block_when_processing_errors(sdp->device))) 632 return -ENXIO; 633 634 if (count < SZ_SG_HEADER) 635 return -EIO; 636 if (copy_from_user(&old_hdr, buf, SZ_SG_HEADER)) 637 return -EFAULT; 638 blocking = !(filp->f_flags & O_NONBLOCK); 639 if (old_hdr.reply_len < 0) 640 return sg_new_write(sfp, filp, buf, count, 641 blocking, 0, 0, NULL); 642 if (count < (SZ_SG_HEADER + 6)) 643 return -EIO; /* The minimum scsi command length is 6 bytes. */ 644 645 buf += SZ_SG_HEADER; 646 if (get_user(opcode, buf)) 647 return -EFAULT; 648 649 if (!(srp = sg_add_request(sfp))) { 650 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sdp, 651 "sg_write: queue full\n")); 652 return -EDOM; 653 } 654 mutex_lock(&sfp->f_mutex); 655 if (sfp->next_cmd_len > 0) { 656 cmd_size = sfp->next_cmd_len; 657 sfp->next_cmd_len = 0; /* reset so only this write() effected */ 658 } else { 659 cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */ 660 if ((opcode >= 0xc0) && old_hdr.twelve_byte) 661 cmd_size = 12; 662 } 663 mutex_unlock(&sfp->f_mutex); 664 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp, 665 "sg_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size)); 666 /* Determine buffer size. */ 667 input_size = count - cmd_size; 668 mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len; 669 mxsize -= SZ_SG_HEADER; 670 input_size -= SZ_SG_HEADER; 671 if (input_size < 0) { 672 sg_remove_request(sfp, srp); 673 return -EIO; /* User did not pass enough bytes for this command. */ 674 } 675 hp = &srp->header; 676 hp->interface_id = '\0'; /* indicator of old interface tunnelled */ 677 hp->cmd_len = (unsigned char) cmd_size; 678 hp->iovec_count = 0; 679 hp->mx_sb_len = 0; 680 if (input_size > 0) 681 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ? 682 SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV; 683 else 684 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE; 685 hp->dxfer_len = mxsize; 686 if ((hp->dxfer_direction == SG_DXFER_TO_DEV) || 687 (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV)) 688 hp->dxferp = (char __user *)buf + cmd_size; 689 else 690 hp->dxferp = NULL; 691 hp->sbp = NULL; 692 hp->timeout = old_hdr.reply_len; /* structure abuse ... */ 693 hp->flags = input_size; /* structure abuse ... */ 694 hp->pack_id = old_hdr.pack_id; 695 hp->usr_ptr = NULL; 696 if (copy_from_user(cmnd, buf, cmd_size)) { 697 sg_remove_request(sfp, srp); 698 return -EFAULT; 699 } 700 /* 701 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV, 702 * but is is possible that the app intended SG_DXFER_TO_DEV, because there 703 * is a non-zero input_size, so emit a warning. 704 */ 705 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) { 706 printk_ratelimited(KERN_WARNING 707 "sg_write: data in/out %d/%d bytes " 708 "for SCSI command 0x%x-- guessing " 709 "data in;\n program %s not setting " 710 "count and/or reply_len properly\n", 711 old_hdr.reply_len - (int)SZ_SG_HEADER, 712 input_size, (unsigned int) cmnd[0], 713 current->comm); 714 } 715 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking); 716 return (k < 0) ? k : count; 717 } 718 719 static ssize_t 720 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf, 721 size_t count, int blocking, int read_only, int sg_io_owned, 722 Sg_request **o_srp) 723 { 724 int k; 725 Sg_request *srp; 726 sg_io_hdr_t *hp; 727 unsigned char cmnd[SG_MAX_CDB_SIZE]; 728 int timeout; 729 unsigned long ul_timeout; 730 731 if (count < SZ_SG_IO_HDR) 732 return -EINVAL; 733 734 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */ 735 if (!(srp = sg_add_request(sfp))) { 736 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp, 737 "sg_new_write: queue full\n")); 738 return -EDOM; 739 } 740 srp->sg_io_owned = sg_io_owned; 741 hp = &srp->header; 742 if (get_sg_io_hdr(hp, buf)) { 743 sg_remove_request(sfp, srp); 744 return -EFAULT; 745 } 746 if (hp->interface_id != 'S') { 747 sg_remove_request(sfp, srp); 748 return -ENOSYS; 749 } 750 if (hp->flags & SG_FLAG_MMAP_IO) { 751 if (hp->dxfer_len > sfp->reserve.bufflen) { 752 sg_remove_request(sfp, srp); 753 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */ 754 } 755 if (hp->flags & SG_FLAG_DIRECT_IO) { 756 sg_remove_request(sfp, srp); 757 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */ 758 } 759 if (sfp->res_in_use) { 760 sg_remove_request(sfp, srp); 761 return -EBUSY; /* reserve buffer already being used */ 762 } 763 } 764 ul_timeout = msecs_to_jiffies(srp->header.timeout); 765 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX; 766 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) { 767 sg_remove_request(sfp, srp); 768 return -EMSGSIZE; 769 } 770 if (copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) { 771 sg_remove_request(sfp, srp); 772 return -EFAULT; 773 } 774 if (read_only && sg_allow_access(file, cmnd)) { 775 sg_remove_request(sfp, srp); 776 return -EPERM; 777 } 778 k = sg_common_write(sfp, srp, cmnd, timeout, blocking); 779 if (k < 0) 780 return k; 781 if (o_srp) 782 *o_srp = srp; 783 return count; 784 } 785 786 static int 787 sg_common_write(Sg_fd * sfp, Sg_request * srp, 788 unsigned char *cmnd, int timeout, int blocking) 789 { 790 int k, at_head; 791 Sg_device *sdp = sfp->parentdp; 792 sg_io_hdr_t *hp = &srp->header; 793 794 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */ 795 hp->status = 0; 796 hp->masked_status = 0; 797 hp->msg_status = 0; 798 hp->info = 0; 799 hp->host_status = 0; 800 hp->driver_status = 0; 801 hp->resid = 0; 802 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 803 "sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n", 804 (int) cmnd[0], (int) hp->cmd_len)); 805 806 if (hp->dxfer_len >= SZ_256M) { 807 sg_remove_request(sfp, srp); 808 return -EINVAL; 809 } 810 811 k = sg_start_req(srp, cmnd); 812 if (k) { 813 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp, 814 "sg_common_write: start_req err=%d\n", k)); 815 sg_finish_rem_req(srp); 816 sg_remove_request(sfp, srp); 817 return k; /* probably out of space --> ENOMEM */ 818 } 819 if (atomic_read(&sdp->detaching)) { 820 if (srp->bio) { 821 scsi_req_free_cmd(scsi_req(srp->rq)); 822 blk_mq_free_request(srp->rq); 823 srp->rq = NULL; 824 } 825 826 sg_finish_rem_req(srp); 827 sg_remove_request(sfp, srp); 828 return -ENODEV; 829 } 830 831 hp->duration = jiffies_to_msecs(jiffies); 832 if (hp->interface_id != '\0' && /* v3 (or later) interface */ 833 (SG_FLAG_Q_AT_TAIL & hp->flags)) 834 at_head = 0; 835 else 836 at_head = 1; 837 838 srp->rq->timeout = timeout; 839 kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */ 840 blk_execute_rq_nowait(srp->rq, at_head, sg_rq_end_io); 841 return 0; 842 } 843 844 static int srp_done(Sg_fd *sfp, Sg_request *srp) 845 { 846 unsigned long flags; 847 int ret; 848 849 read_lock_irqsave(&sfp->rq_list_lock, flags); 850 ret = srp->done; 851 read_unlock_irqrestore(&sfp->rq_list_lock, flags); 852 return ret; 853 } 854 855 static int max_sectors_bytes(struct request_queue *q) 856 { 857 unsigned int max_sectors = queue_max_sectors(q); 858 859 max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9); 860 861 return max_sectors << 9; 862 } 863 864 static void 865 sg_fill_request_table(Sg_fd *sfp, sg_req_info_t *rinfo) 866 { 867 Sg_request *srp; 868 int val; 869 unsigned int ms; 870 871 val = 0; 872 list_for_each_entry(srp, &sfp->rq_list, entry) { 873 if (val >= SG_MAX_QUEUE) 874 break; 875 rinfo[val].req_state = srp->done + 1; 876 rinfo[val].problem = 877 srp->header.masked_status & 878 srp->header.host_status & 879 srp->header.driver_status; 880 if (srp->done) 881 rinfo[val].duration = 882 srp->header.duration; 883 else { 884 ms = jiffies_to_msecs(jiffies); 885 rinfo[val].duration = 886 (ms > srp->header.duration) ? 887 (ms - srp->header.duration) : 0; 888 } 889 rinfo[val].orphan = srp->orphan; 890 rinfo[val].sg_io_owned = srp->sg_io_owned; 891 rinfo[val].pack_id = srp->header.pack_id; 892 rinfo[val].usr_ptr = srp->header.usr_ptr; 893 val++; 894 } 895 } 896 897 #ifdef CONFIG_COMPAT 898 struct compat_sg_req_info { /* used by SG_GET_REQUEST_TABLE ioctl() */ 899 char req_state; 900 char orphan; 901 char sg_io_owned; 902 char problem; 903 int pack_id; 904 compat_uptr_t usr_ptr; 905 unsigned int duration; 906 int unused; 907 }; 908 909 static int put_compat_request_table(struct compat_sg_req_info __user *o, 910 struct sg_req_info *rinfo) 911 { 912 int i; 913 for (i = 0; i < SG_MAX_QUEUE; i++) { 914 if (copy_to_user(o + i, rinfo + i, offsetof(sg_req_info_t, usr_ptr)) || 915 put_user((uintptr_t)rinfo[i].usr_ptr, &o[i].usr_ptr) || 916 put_user(rinfo[i].duration, &o[i].duration) || 917 put_user(rinfo[i].unused, &o[i].unused)) 918 return -EFAULT; 919 } 920 return 0; 921 } 922 #endif 923 924 static long 925 sg_ioctl_common(struct file *filp, Sg_device *sdp, Sg_fd *sfp, 926 unsigned int cmd_in, void __user *p) 927 { 928 int __user *ip = p; 929 int result, val, read_only; 930 Sg_request *srp; 931 unsigned long iflags; 932 933 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 934 "sg_ioctl: cmd=0x%x\n", (int) cmd_in)); 935 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE)); 936 937 switch (cmd_in) { 938 case SG_IO: 939 if (atomic_read(&sdp->detaching)) 940 return -ENODEV; 941 if (!scsi_block_when_processing_errors(sdp->device)) 942 return -ENXIO; 943 result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR, 944 1, read_only, 1, &srp); 945 if (result < 0) 946 return result; 947 result = wait_event_interruptible(sfp->read_wait, 948 (srp_done(sfp, srp) || atomic_read(&sdp->detaching))); 949 if (atomic_read(&sdp->detaching)) 950 return -ENODEV; 951 write_lock_irq(&sfp->rq_list_lock); 952 if (srp->done) { 953 srp->done = 2; 954 write_unlock_irq(&sfp->rq_list_lock); 955 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp); 956 return (result < 0) ? result : 0; 957 } 958 srp->orphan = 1; 959 write_unlock_irq(&sfp->rq_list_lock); 960 return result; /* -ERESTARTSYS because signal hit process */ 961 case SG_SET_TIMEOUT: 962 result = get_user(val, ip); 963 if (result) 964 return result; 965 if (val < 0) 966 return -EIO; 967 if (val >= mult_frac((s64)INT_MAX, USER_HZ, HZ)) 968 val = min_t(s64, mult_frac((s64)INT_MAX, USER_HZ, HZ), 969 INT_MAX); 970 sfp->timeout_user = val; 971 sfp->timeout = mult_frac(val, HZ, USER_HZ); 972 973 return 0; 974 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */ 975 /* strange ..., for backward compatibility */ 976 return sfp->timeout_user; 977 case SG_SET_FORCE_LOW_DMA: 978 /* 979 * N.B. This ioctl never worked properly, but failed to 980 * return an error value. So returning '0' to keep compability 981 * with legacy applications. 982 */ 983 return 0; 984 case SG_GET_LOW_DMA: 985 return put_user(0, ip); 986 case SG_GET_SCSI_ID: 987 { 988 sg_scsi_id_t v; 989 990 if (atomic_read(&sdp->detaching)) 991 return -ENODEV; 992 memset(&v, 0, sizeof(v)); 993 v.host_no = sdp->device->host->host_no; 994 v.channel = sdp->device->channel; 995 v.scsi_id = sdp->device->id; 996 v.lun = sdp->device->lun; 997 v.scsi_type = sdp->device->type; 998 v.h_cmd_per_lun = sdp->device->host->cmd_per_lun; 999 v.d_queue_depth = sdp->device->queue_depth; 1000 if (copy_to_user(p, &v, sizeof(sg_scsi_id_t))) 1001 return -EFAULT; 1002 return 0; 1003 } 1004 case SG_SET_FORCE_PACK_ID: 1005 result = get_user(val, ip); 1006 if (result) 1007 return result; 1008 sfp->force_packid = val ? 1 : 0; 1009 return 0; 1010 case SG_GET_PACK_ID: 1011 read_lock_irqsave(&sfp->rq_list_lock, iflags); 1012 list_for_each_entry(srp, &sfp->rq_list, entry) { 1013 if ((1 == srp->done) && (!srp->sg_io_owned)) { 1014 read_unlock_irqrestore(&sfp->rq_list_lock, 1015 iflags); 1016 return put_user(srp->header.pack_id, ip); 1017 } 1018 } 1019 read_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1020 return put_user(-1, ip); 1021 case SG_GET_NUM_WAITING: 1022 read_lock_irqsave(&sfp->rq_list_lock, iflags); 1023 val = 0; 1024 list_for_each_entry(srp, &sfp->rq_list, entry) { 1025 if ((1 == srp->done) && (!srp->sg_io_owned)) 1026 ++val; 1027 } 1028 read_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1029 return put_user(val, ip); 1030 case SG_GET_SG_TABLESIZE: 1031 return put_user(sdp->sg_tablesize, ip); 1032 case SG_SET_RESERVED_SIZE: 1033 result = get_user(val, ip); 1034 if (result) 1035 return result; 1036 if (val < 0) 1037 return -EINVAL; 1038 val = min_t(int, val, 1039 max_sectors_bytes(sdp->device->request_queue)); 1040 mutex_lock(&sfp->f_mutex); 1041 if (val != sfp->reserve.bufflen) { 1042 if (sfp->mmap_called || 1043 sfp->res_in_use) { 1044 mutex_unlock(&sfp->f_mutex); 1045 return -EBUSY; 1046 } 1047 1048 sg_remove_scat(sfp, &sfp->reserve); 1049 sg_build_reserve(sfp, val); 1050 } 1051 mutex_unlock(&sfp->f_mutex); 1052 return 0; 1053 case SG_GET_RESERVED_SIZE: 1054 val = min_t(int, sfp->reserve.bufflen, 1055 max_sectors_bytes(sdp->device->request_queue)); 1056 return put_user(val, ip); 1057 case SG_SET_COMMAND_Q: 1058 result = get_user(val, ip); 1059 if (result) 1060 return result; 1061 sfp->cmd_q = val ? 1 : 0; 1062 return 0; 1063 case SG_GET_COMMAND_Q: 1064 return put_user((int) sfp->cmd_q, ip); 1065 case SG_SET_KEEP_ORPHAN: 1066 result = get_user(val, ip); 1067 if (result) 1068 return result; 1069 sfp->keep_orphan = val; 1070 return 0; 1071 case SG_GET_KEEP_ORPHAN: 1072 return put_user((int) sfp->keep_orphan, ip); 1073 case SG_NEXT_CMD_LEN: 1074 result = get_user(val, ip); 1075 if (result) 1076 return result; 1077 if (val > SG_MAX_CDB_SIZE) 1078 return -ENOMEM; 1079 sfp->next_cmd_len = (val > 0) ? val : 0; 1080 return 0; 1081 case SG_GET_VERSION_NUM: 1082 return put_user(sg_version_num, ip); 1083 case SG_GET_ACCESS_COUNT: 1084 /* faked - we don't have a real access count anymore */ 1085 val = (sdp->device ? 1 : 0); 1086 return put_user(val, ip); 1087 case SG_GET_REQUEST_TABLE: 1088 { 1089 sg_req_info_t *rinfo; 1090 1091 rinfo = kcalloc(SG_MAX_QUEUE, SZ_SG_REQ_INFO, 1092 GFP_KERNEL); 1093 if (!rinfo) 1094 return -ENOMEM; 1095 read_lock_irqsave(&sfp->rq_list_lock, iflags); 1096 sg_fill_request_table(sfp, rinfo); 1097 read_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1098 #ifdef CONFIG_COMPAT 1099 if (in_compat_syscall()) 1100 result = put_compat_request_table(p, rinfo); 1101 else 1102 #endif 1103 result = copy_to_user(p, rinfo, 1104 SZ_SG_REQ_INFO * SG_MAX_QUEUE); 1105 result = result ? -EFAULT : 0; 1106 kfree(rinfo); 1107 return result; 1108 } 1109 case SG_EMULATED_HOST: 1110 if (atomic_read(&sdp->detaching)) 1111 return -ENODEV; 1112 return put_user(sdp->device->host->hostt->emulated, ip); 1113 case SCSI_IOCTL_SEND_COMMAND: 1114 if (atomic_read(&sdp->detaching)) 1115 return -ENODEV; 1116 return scsi_ioctl(sdp->device, filp->f_mode, cmd_in, p); 1117 case SG_SET_DEBUG: 1118 result = get_user(val, ip); 1119 if (result) 1120 return result; 1121 sdp->sgdebug = (char) val; 1122 return 0; 1123 case BLKSECTGET: 1124 return put_user(max_sectors_bytes(sdp->device->request_queue), 1125 ip); 1126 case BLKTRACESETUP: 1127 return blk_trace_setup(sdp->device->request_queue, sdp->name, 1128 MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1129 NULL, p); 1130 case BLKTRACESTART: 1131 return blk_trace_startstop(sdp->device->request_queue, 1); 1132 case BLKTRACESTOP: 1133 return blk_trace_startstop(sdp->device->request_queue, 0); 1134 case BLKTRACETEARDOWN: 1135 return blk_trace_remove(sdp->device->request_queue); 1136 case SCSI_IOCTL_GET_IDLUN: 1137 case SCSI_IOCTL_GET_BUS_NUMBER: 1138 case SCSI_IOCTL_PROBE_HOST: 1139 case SG_GET_TRANSFORM: 1140 case SG_SCSI_RESET: 1141 if (atomic_read(&sdp->detaching)) 1142 return -ENODEV; 1143 break; 1144 default: 1145 if (read_only) 1146 return -EPERM; /* don't know so take safe approach */ 1147 break; 1148 } 1149 1150 result = scsi_ioctl_block_when_processing_errors(sdp->device, 1151 cmd_in, filp->f_flags & O_NDELAY); 1152 if (result) 1153 return result; 1154 1155 return -ENOIOCTLCMD; 1156 } 1157 1158 static long 1159 sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg) 1160 { 1161 void __user *p = (void __user *)arg; 1162 Sg_device *sdp; 1163 Sg_fd *sfp; 1164 int ret; 1165 1166 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 1167 return -ENXIO; 1168 1169 ret = sg_ioctl_common(filp, sdp, sfp, cmd_in, p); 1170 if (ret != -ENOIOCTLCMD) 1171 return ret; 1172 return scsi_ioctl(sdp->device, filp->f_mode, cmd_in, p); 1173 } 1174 1175 static __poll_t 1176 sg_poll(struct file *filp, poll_table * wait) 1177 { 1178 __poll_t res = 0; 1179 Sg_device *sdp; 1180 Sg_fd *sfp; 1181 Sg_request *srp; 1182 int count = 0; 1183 unsigned long iflags; 1184 1185 sfp = filp->private_data; 1186 if (!sfp) 1187 return EPOLLERR; 1188 sdp = sfp->parentdp; 1189 if (!sdp) 1190 return EPOLLERR; 1191 poll_wait(filp, &sfp->read_wait, wait); 1192 read_lock_irqsave(&sfp->rq_list_lock, iflags); 1193 list_for_each_entry(srp, &sfp->rq_list, entry) { 1194 /* if any read waiting, flag it */ 1195 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned)) 1196 res = EPOLLIN | EPOLLRDNORM; 1197 ++count; 1198 } 1199 read_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1200 1201 if (atomic_read(&sdp->detaching)) 1202 res |= EPOLLHUP; 1203 else if (!sfp->cmd_q) { 1204 if (0 == count) 1205 res |= EPOLLOUT | EPOLLWRNORM; 1206 } else if (count < SG_MAX_QUEUE) 1207 res |= EPOLLOUT | EPOLLWRNORM; 1208 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 1209 "sg_poll: res=0x%x\n", (__force u32) res)); 1210 return res; 1211 } 1212 1213 static int 1214 sg_fasync(int fd, struct file *filp, int mode) 1215 { 1216 Sg_device *sdp; 1217 Sg_fd *sfp; 1218 1219 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 1220 return -ENXIO; 1221 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 1222 "sg_fasync: mode=%d\n", mode)); 1223 1224 return fasync_helper(fd, filp, mode, &sfp->async_qp); 1225 } 1226 1227 static vm_fault_t 1228 sg_vma_fault(struct vm_fault *vmf) 1229 { 1230 struct vm_area_struct *vma = vmf->vma; 1231 Sg_fd *sfp; 1232 unsigned long offset, len, sa; 1233 Sg_scatter_hold *rsv_schp; 1234 int k, length; 1235 1236 if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data))) 1237 return VM_FAULT_SIGBUS; 1238 rsv_schp = &sfp->reserve; 1239 offset = vmf->pgoff << PAGE_SHIFT; 1240 if (offset >= rsv_schp->bufflen) 1241 return VM_FAULT_SIGBUS; 1242 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp, 1243 "sg_vma_fault: offset=%lu, scatg=%d\n", 1244 offset, rsv_schp->k_use_sg)); 1245 sa = vma->vm_start; 1246 length = 1 << (PAGE_SHIFT + rsv_schp->page_order); 1247 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) { 1248 len = vma->vm_end - sa; 1249 len = (len < length) ? len : length; 1250 if (offset < len) { 1251 struct page *page = nth_page(rsv_schp->pages[k], 1252 offset >> PAGE_SHIFT); 1253 get_page(page); /* increment page count */ 1254 vmf->page = page; 1255 return 0; /* success */ 1256 } 1257 sa += len; 1258 offset -= len; 1259 } 1260 1261 return VM_FAULT_SIGBUS; 1262 } 1263 1264 static const struct vm_operations_struct sg_mmap_vm_ops = { 1265 .fault = sg_vma_fault, 1266 }; 1267 1268 static int 1269 sg_mmap(struct file *filp, struct vm_area_struct *vma) 1270 { 1271 Sg_fd *sfp; 1272 unsigned long req_sz, len, sa; 1273 Sg_scatter_hold *rsv_schp; 1274 int k, length; 1275 int ret = 0; 1276 1277 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data))) 1278 return -ENXIO; 1279 req_sz = vma->vm_end - vma->vm_start; 1280 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp, 1281 "sg_mmap starting, vm_start=%p, len=%d\n", 1282 (void *) vma->vm_start, (int) req_sz)); 1283 if (vma->vm_pgoff) 1284 return -EINVAL; /* want no offset */ 1285 rsv_schp = &sfp->reserve; 1286 mutex_lock(&sfp->f_mutex); 1287 if (req_sz > rsv_schp->bufflen) { 1288 ret = -ENOMEM; /* cannot map more than reserved buffer */ 1289 goto out; 1290 } 1291 1292 sa = vma->vm_start; 1293 length = 1 << (PAGE_SHIFT + rsv_schp->page_order); 1294 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) { 1295 len = vma->vm_end - sa; 1296 len = (len < length) ? len : length; 1297 sa += len; 1298 } 1299 1300 sfp->mmap_called = 1; 1301 vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP; 1302 vma->vm_private_data = sfp; 1303 vma->vm_ops = &sg_mmap_vm_ops; 1304 out: 1305 mutex_unlock(&sfp->f_mutex); 1306 return ret; 1307 } 1308 1309 static void 1310 sg_rq_end_io_usercontext(struct work_struct *work) 1311 { 1312 struct sg_request *srp = container_of(work, struct sg_request, ew.work); 1313 struct sg_fd *sfp = srp->parentfp; 1314 1315 sg_finish_rem_req(srp); 1316 sg_remove_request(sfp, srp); 1317 kref_put(&sfp->f_ref, sg_remove_sfp); 1318 } 1319 1320 /* 1321 * This function is a "bottom half" handler that is called by the mid 1322 * level when a command is completed (or has failed). 1323 */ 1324 static void 1325 sg_rq_end_io(struct request *rq, blk_status_t status) 1326 { 1327 struct sg_request *srp = rq->end_io_data; 1328 struct scsi_request *req = scsi_req(rq); 1329 Sg_device *sdp; 1330 Sg_fd *sfp; 1331 unsigned long iflags; 1332 unsigned int ms; 1333 char *sense; 1334 int result, resid, done = 1; 1335 1336 if (WARN_ON(srp->done != 0)) 1337 return; 1338 1339 sfp = srp->parentfp; 1340 if (WARN_ON(sfp == NULL)) 1341 return; 1342 1343 sdp = sfp->parentdp; 1344 if (unlikely(atomic_read(&sdp->detaching))) 1345 pr_info("%s: device detaching\n", __func__); 1346 1347 sense = req->sense; 1348 result = req->result; 1349 resid = req->resid_len; 1350 1351 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp, 1352 "sg_cmd_done: pack_id=%d, res=0x%x\n", 1353 srp->header.pack_id, result)); 1354 srp->header.resid = resid; 1355 ms = jiffies_to_msecs(jiffies); 1356 srp->header.duration = (ms > srp->header.duration) ? 1357 (ms - srp->header.duration) : 0; 1358 if (0 != result) { 1359 struct scsi_sense_hdr sshdr; 1360 1361 srp->header.status = 0xff & result; 1362 srp->header.masked_status = status_byte(result); 1363 srp->header.msg_status = COMMAND_COMPLETE; 1364 srp->header.host_status = host_byte(result); 1365 srp->header.driver_status = driver_byte(result); 1366 if ((sdp->sgdebug > 0) && 1367 ((CHECK_CONDITION == srp->header.masked_status) || 1368 (COMMAND_TERMINATED == srp->header.masked_status))) 1369 __scsi_print_sense(sdp->device, __func__, sense, 1370 SCSI_SENSE_BUFFERSIZE); 1371 1372 /* Following if statement is a patch supplied by Eric Youngdale */ 1373 if (driver_byte(result) != 0 1374 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr) 1375 && !scsi_sense_is_deferred(&sshdr) 1376 && sshdr.sense_key == UNIT_ATTENTION 1377 && sdp->device->removable) { 1378 /* Detected possible disc change. Set the bit - this */ 1379 /* may be used if there are filesystems using this device */ 1380 sdp->device->changed = 1; 1381 } 1382 } 1383 1384 if (req->sense_len) 1385 memcpy(srp->sense_b, req->sense, SCSI_SENSE_BUFFERSIZE); 1386 1387 /* Rely on write phase to clean out srp status values, so no "else" */ 1388 1389 /* 1390 * Free the request as soon as it is complete so that its resources 1391 * can be reused without waiting for userspace to read() the 1392 * result. But keep the associated bio (if any) around until 1393 * blk_rq_unmap_user() can be called from user context. 1394 */ 1395 srp->rq = NULL; 1396 scsi_req_free_cmd(scsi_req(rq)); 1397 blk_mq_free_request(rq); 1398 1399 write_lock_irqsave(&sfp->rq_list_lock, iflags); 1400 if (unlikely(srp->orphan)) { 1401 if (sfp->keep_orphan) 1402 srp->sg_io_owned = 0; 1403 else 1404 done = 0; 1405 } 1406 srp->done = done; 1407 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1408 1409 if (likely(done)) { 1410 /* Now wake up any sg_read() that is waiting for this 1411 * packet. 1412 */ 1413 wake_up_interruptible(&sfp->read_wait); 1414 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN); 1415 kref_put(&sfp->f_ref, sg_remove_sfp); 1416 } else { 1417 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext); 1418 schedule_work(&srp->ew.work); 1419 } 1420 } 1421 1422 static const struct file_operations sg_fops = { 1423 .owner = THIS_MODULE, 1424 .read = sg_read, 1425 .write = sg_write, 1426 .poll = sg_poll, 1427 .unlocked_ioctl = sg_ioctl, 1428 .compat_ioctl = compat_ptr_ioctl, 1429 .open = sg_open, 1430 .mmap = sg_mmap, 1431 .release = sg_release, 1432 .fasync = sg_fasync, 1433 .llseek = no_llseek, 1434 }; 1435 1436 static struct class *sg_sysfs_class; 1437 1438 static int sg_sysfs_valid = 0; 1439 1440 static Sg_device * 1441 sg_alloc(struct scsi_device *scsidp) 1442 { 1443 struct request_queue *q = scsidp->request_queue; 1444 Sg_device *sdp; 1445 unsigned long iflags; 1446 int error; 1447 u32 k; 1448 1449 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL); 1450 if (!sdp) { 1451 sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device " 1452 "failure\n", __func__); 1453 return ERR_PTR(-ENOMEM); 1454 } 1455 1456 idr_preload(GFP_KERNEL); 1457 write_lock_irqsave(&sg_index_lock, iflags); 1458 1459 error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT); 1460 if (error < 0) { 1461 if (error == -ENOSPC) { 1462 sdev_printk(KERN_WARNING, scsidp, 1463 "Unable to attach sg device type=%d, minor number exceeds %d\n", 1464 scsidp->type, SG_MAX_DEVS - 1); 1465 error = -ENODEV; 1466 } else { 1467 sdev_printk(KERN_WARNING, scsidp, "%s: idr " 1468 "allocation Sg_device failure: %d\n", 1469 __func__, error); 1470 } 1471 goto out_unlock; 1472 } 1473 k = error; 1474 1475 SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp, 1476 "sg_alloc: dev=%d \n", k)); 1477 sprintf(sdp->name, "sg%d", k); 1478 sdp->device = scsidp; 1479 mutex_init(&sdp->open_rel_lock); 1480 INIT_LIST_HEAD(&sdp->sfds); 1481 init_waitqueue_head(&sdp->open_wait); 1482 atomic_set(&sdp->detaching, 0); 1483 rwlock_init(&sdp->sfd_lock); 1484 sdp->sg_tablesize = queue_max_segments(q); 1485 sdp->index = k; 1486 kref_init(&sdp->d_ref); 1487 error = 0; 1488 1489 out_unlock: 1490 write_unlock_irqrestore(&sg_index_lock, iflags); 1491 idr_preload_end(); 1492 1493 if (error) { 1494 kfree(sdp); 1495 return ERR_PTR(error); 1496 } 1497 return sdp; 1498 } 1499 1500 static int 1501 sg_add_device(struct device *cl_dev, struct class_interface *cl_intf) 1502 { 1503 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent); 1504 Sg_device *sdp = NULL; 1505 struct cdev * cdev = NULL; 1506 int error; 1507 unsigned long iflags; 1508 1509 error = -ENOMEM; 1510 cdev = cdev_alloc(); 1511 if (!cdev) { 1512 pr_warn("%s: cdev_alloc failed\n", __func__); 1513 goto out; 1514 } 1515 cdev->owner = THIS_MODULE; 1516 cdev->ops = &sg_fops; 1517 1518 sdp = sg_alloc(scsidp); 1519 if (IS_ERR(sdp)) { 1520 pr_warn("%s: sg_alloc failed\n", __func__); 1521 error = PTR_ERR(sdp); 1522 goto out; 1523 } 1524 1525 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1); 1526 if (error) 1527 goto cdev_add_err; 1528 1529 sdp->cdev = cdev; 1530 if (sg_sysfs_valid) { 1531 struct device *sg_class_member; 1532 1533 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent, 1534 MKDEV(SCSI_GENERIC_MAJOR, 1535 sdp->index), 1536 sdp, "%s", sdp->name); 1537 if (IS_ERR(sg_class_member)) { 1538 pr_err("%s: device_create failed\n", __func__); 1539 error = PTR_ERR(sg_class_member); 1540 goto cdev_add_err; 1541 } 1542 error = sysfs_create_link(&scsidp->sdev_gendev.kobj, 1543 &sg_class_member->kobj, "generic"); 1544 if (error) 1545 pr_err("%s: unable to make symlink 'generic' back " 1546 "to sg%d\n", __func__, sdp->index); 1547 } else 1548 pr_warn("%s: sg_sys Invalid\n", __func__); 1549 1550 sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d " 1551 "type %d\n", sdp->index, scsidp->type); 1552 1553 dev_set_drvdata(cl_dev, sdp); 1554 1555 return 0; 1556 1557 cdev_add_err: 1558 write_lock_irqsave(&sg_index_lock, iflags); 1559 idr_remove(&sg_index_idr, sdp->index); 1560 write_unlock_irqrestore(&sg_index_lock, iflags); 1561 kfree(sdp); 1562 1563 out: 1564 if (cdev) 1565 cdev_del(cdev); 1566 return error; 1567 } 1568 1569 static void 1570 sg_device_destroy(struct kref *kref) 1571 { 1572 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref); 1573 unsigned long flags; 1574 1575 /* CAUTION! Note that the device can still be found via idr_find() 1576 * even though the refcount is 0. Therefore, do idr_remove() BEFORE 1577 * any other cleanup. 1578 */ 1579 1580 write_lock_irqsave(&sg_index_lock, flags); 1581 idr_remove(&sg_index_idr, sdp->index); 1582 write_unlock_irqrestore(&sg_index_lock, flags); 1583 1584 SCSI_LOG_TIMEOUT(3, 1585 sg_printk(KERN_INFO, sdp, "sg_device_destroy\n")); 1586 1587 kfree(sdp); 1588 } 1589 1590 static void 1591 sg_remove_device(struct device *cl_dev, struct class_interface *cl_intf) 1592 { 1593 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent); 1594 Sg_device *sdp = dev_get_drvdata(cl_dev); 1595 unsigned long iflags; 1596 Sg_fd *sfp; 1597 int val; 1598 1599 if (!sdp) 1600 return; 1601 /* want sdp->detaching non-zero as soon as possible */ 1602 val = atomic_inc_return(&sdp->detaching); 1603 if (val > 1) 1604 return; /* only want to do following once per device */ 1605 1606 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 1607 "%s\n", __func__)); 1608 1609 read_lock_irqsave(&sdp->sfd_lock, iflags); 1610 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) { 1611 wake_up_interruptible_all(&sfp->read_wait); 1612 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP); 1613 } 1614 wake_up_interruptible_all(&sdp->open_wait); 1615 read_unlock_irqrestore(&sdp->sfd_lock, iflags); 1616 1617 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic"); 1618 device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index)); 1619 cdev_del(sdp->cdev); 1620 sdp->cdev = NULL; 1621 1622 kref_put(&sdp->d_ref, sg_device_destroy); 1623 } 1624 1625 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR); 1626 module_param_named(def_reserved_size, def_reserved_size, int, 1627 S_IRUGO | S_IWUSR); 1628 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR); 1629 1630 MODULE_AUTHOR("Douglas Gilbert"); 1631 MODULE_DESCRIPTION("SCSI generic (sg) driver"); 1632 MODULE_LICENSE("GPL"); 1633 MODULE_VERSION(SG_VERSION_STR); 1634 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR); 1635 1636 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element " 1637 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))"); 1638 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd"); 1639 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))"); 1640 1641 #ifdef CONFIG_SYSCTL 1642 #include <linux/sysctl.h> 1643 1644 static struct ctl_table sg_sysctls[] = { 1645 { 1646 .procname = "sg-big-buff", 1647 .data = &sg_big_buff, 1648 .maxlen = sizeof(int), 1649 .mode = 0444, 1650 .proc_handler = proc_dointvec, 1651 }, 1652 {} 1653 }; 1654 1655 static struct ctl_table_header *hdr; 1656 static void register_sg_sysctls(void) 1657 { 1658 if (!hdr) 1659 hdr = register_sysctl("kernel", sg_sysctls); 1660 } 1661 1662 static void unregister_sg_sysctls(void) 1663 { 1664 if (hdr) 1665 unregister_sysctl_table(hdr); 1666 } 1667 #else 1668 #define register_sg_sysctls() do { } while (0) 1669 #define unregister_sg_sysctls() do { } while (0) 1670 #endif /* CONFIG_SYSCTL */ 1671 1672 static int __init 1673 init_sg(void) 1674 { 1675 int rc; 1676 1677 if (scatter_elem_sz < PAGE_SIZE) { 1678 scatter_elem_sz = PAGE_SIZE; 1679 scatter_elem_sz_prev = scatter_elem_sz; 1680 } 1681 if (def_reserved_size >= 0) 1682 sg_big_buff = def_reserved_size; 1683 else 1684 def_reserved_size = sg_big_buff; 1685 1686 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), 1687 SG_MAX_DEVS, "sg"); 1688 if (rc) 1689 return rc; 1690 sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic"); 1691 if ( IS_ERR(sg_sysfs_class) ) { 1692 rc = PTR_ERR(sg_sysfs_class); 1693 goto err_out; 1694 } 1695 sg_sysfs_valid = 1; 1696 rc = scsi_register_interface(&sg_interface); 1697 if (0 == rc) { 1698 #ifdef CONFIG_SCSI_PROC_FS 1699 sg_proc_init(); 1700 #endif /* CONFIG_SCSI_PROC_FS */ 1701 return 0; 1702 } 1703 class_destroy(sg_sysfs_class); 1704 register_sg_sysctls(); 1705 err_out: 1706 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS); 1707 return rc; 1708 } 1709 1710 static void __exit 1711 exit_sg(void) 1712 { 1713 unregister_sg_sysctls(); 1714 #ifdef CONFIG_SCSI_PROC_FS 1715 remove_proc_subtree("scsi/sg", NULL); 1716 #endif /* CONFIG_SCSI_PROC_FS */ 1717 scsi_unregister_interface(&sg_interface); 1718 class_destroy(sg_sysfs_class); 1719 sg_sysfs_valid = 0; 1720 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), 1721 SG_MAX_DEVS); 1722 idr_destroy(&sg_index_idr); 1723 } 1724 1725 static int 1726 sg_start_req(Sg_request *srp, unsigned char *cmd) 1727 { 1728 int res; 1729 struct request *rq; 1730 struct scsi_request *req; 1731 Sg_fd *sfp = srp->parentfp; 1732 sg_io_hdr_t *hp = &srp->header; 1733 int dxfer_len = (int) hp->dxfer_len; 1734 int dxfer_dir = hp->dxfer_direction; 1735 unsigned int iov_count = hp->iovec_count; 1736 Sg_scatter_hold *req_schp = &srp->data; 1737 Sg_scatter_hold *rsv_schp = &sfp->reserve; 1738 struct request_queue *q = sfp->parentdp->device->request_queue; 1739 struct rq_map_data *md, map_data; 1740 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ; 1741 unsigned char *long_cmdp = NULL; 1742 1743 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 1744 "sg_start_req: dxfer_len=%d\n", 1745 dxfer_len)); 1746 1747 if (hp->cmd_len > BLK_MAX_CDB) { 1748 long_cmdp = kzalloc(hp->cmd_len, GFP_KERNEL); 1749 if (!long_cmdp) 1750 return -ENOMEM; 1751 } 1752 1753 /* 1754 * NOTE 1755 * 1756 * With scsi-mq enabled, there are a fixed number of preallocated 1757 * requests equal in number to shost->can_queue. If all of the 1758 * preallocated requests are already in use, then scsi_alloc_request() 1759 * will sleep until an active command completes, freeing up a request. 1760 * Although waiting in an asynchronous interface is less than ideal, we 1761 * do not want to use BLK_MQ_REQ_NOWAIT here because userspace might 1762 * not expect an EWOULDBLOCK from this condition. 1763 */ 1764 rq = scsi_alloc_request(q, hp->dxfer_direction == SG_DXFER_TO_DEV ? 1765 REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0); 1766 if (IS_ERR(rq)) { 1767 kfree(long_cmdp); 1768 return PTR_ERR(rq); 1769 } 1770 req = scsi_req(rq); 1771 1772 if (hp->cmd_len > BLK_MAX_CDB) 1773 req->cmd = long_cmdp; 1774 memcpy(req->cmd, cmd, hp->cmd_len); 1775 req->cmd_len = hp->cmd_len; 1776 1777 srp->rq = rq; 1778 rq->end_io_data = srp; 1779 req->retries = SG_DEFAULT_RETRIES; 1780 1781 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE)) 1782 return 0; 1783 1784 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO && 1785 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count && 1786 blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len)) 1787 md = NULL; 1788 else 1789 md = &map_data; 1790 1791 if (md) { 1792 mutex_lock(&sfp->f_mutex); 1793 if (dxfer_len <= rsv_schp->bufflen && 1794 !sfp->res_in_use) { 1795 sfp->res_in_use = 1; 1796 sg_link_reserve(sfp, srp, dxfer_len); 1797 } else if (hp->flags & SG_FLAG_MMAP_IO) { 1798 res = -EBUSY; /* sfp->res_in_use == 1 */ 1799 if (dxfer_len > rsv_schp->bufflen) 1800 res = -ENOMEM; 1801 mutex_unlock(&sfp->f_mutex); 1802 return res; 1803 } else { 1804 res = sg_build_indirect(req_schp, sfp, dxfer_len); 1805 if (res) { 1806 mutex_unlock(&sfp->f_mutex); 1807 return res; 1808 } 1809 } 1810 mutex_unlock(&sfp->f_mutex); 1811 1812 md->pages = req_schp->pages; 1813 md->page_order = req_schp->page_order; 1814 md->nr_entries = req_schp->k_use_sg; 1815 md->offset = 0; 1816 md->null_mapped = hp->dxferp ? 0 : 1; 1817 if (dxfer_dir == SG_DXFER_TO_FROM_DEV) 1818 md->from_user = 1; 1819 else 1820 md->from_user = 0; 1821 } 1822 1823 if (iov_count) { 1824 struct iovec *iov = NULL; 1825 struct iov_iter i; 1826 1827 res = import_iovec(rw, hp->dxferp, iov_count, 0, &iov, &i); 1828 if (res < 0) 1829 return res; 1830 1831 iov_iter_truncate(&i, hp->dxfer_len); 1832 if (!iov_iter_count(&i)) { 1833 kfree(iov); 1834 return -EINVAL; 1835 } 1836 1837 res = blk_rq_map_user_iov(q, rq, md, &i, GFP_ATOMIC); 1838 kfree(iov); 1839 } else 1840 res = blk_rq_map_user(q, rq, md, hp->dxferp, 1841 hp->dxfer_len, GFP_ATOMIC); 1842 1843 if (!res) { 1844 srp->bio = rq->bio; 1845 1846 if (!md) { 1847 req_schp->dio_in_use = 1; 1848 hp->info |= SG_INFO_DIRECT_IO; 1849 } 1850 } 1851 return res; 1852 } 1853 1854 static int 1855 sg_finish_rem_req(Sg_request *srp) 1856 { 1857 int ret = 0; 1858 1859 Sg_fd *sfp = srp->parentfp; 1860 Sg_scatter_hold *req_schp = &srp->data; 1861 1862 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 1863 "sg_finish_rem_req: res_used=%d\n", 1864 (int) srp->res_used)); 1865 if (srp->bio) 1866 ret = blk_rq_unmap_user(srp->bio); 1867 1868 if (srp->rq) { 1869 scsi_req_free_cmd(scsi_req(srp->rq)); 1870 blk_mq_free_request(srp->rq); 1871 } 1872 1873 if (srp->res_used) 1874 sg_unlink_reserve(sfp, srp); 1875 else 1876 sg_remove_scat(sfp, req_schp); 1877 1878 return ret; 1879 } 1880 1881 static int 1882 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize) 1883 { 1884 int sg_bufflen = tablesize * sizeof(struct page *); 1885 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN; 1886 1887 schp->pages = kzalloc(sg_bufflen, gfp_flags); 1888 if (!schp->pages) 1889 return -ENOMEM; 1890 schp->sglist_len = sg_bufflen; 1891 return tablesize; /* number of scat_gath elements allocated */ 1892 } 1893 1894 static int 1895 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size) 1896 { 1897 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems; 1898 int sg_tablesize = sfp->parentdp->sg_tablesize; 1899 int blk_size = buff_size, order; 1900 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN | __GFP_ZERO; 1901 1902 if (blk_size < 0) 1903 return -EFAULT; 1904 if (0 == blk_size) 1905 ++blk_size; /* don't know why */ 1906 /* round request up to next highest SG_SECTOR_SZ byte boundary */ 1907 blk_size = ALIGN(blk_size, SG_SECTOR_SZ); 1908 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 1909 "sg_build_indirect: buff_size=%d, blk_size=%d\n", 1910 buff_size, blk_size)); 1911 1912 /* N.B. ret_sz carried into this block ... */ 1913 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize); 1914 if (mx_sc_elems < 0) 1915 return mx_sc_elems; /* most likely -ENOMEM */ 1916 1917 num = scatter_elem_sz; 1918 if (unlikely(num != scatter_elem_sz_prev)) { 1919 if (num < PAGE_SIZE) { 1920 scatter_elem_sz = PAGE_SIZE; 1921 scatter_elem_sz_prev = PAGE_SIZE; 1922 } else 1923 scatter_elem_sz_prev = num; 1924 } 1925 1926 order = get_order(num); 1927 retry: 1928 ret_sz = 1 << (PAGE_SHIFT + order); 1929 1930 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems; 1931 k++, rem_sz -= ret_sz) { 1932 1933 num = (rem_sz > scatter_elem_sz_prev) ? 1934 scatter_elem_sz_prev : rem_sz; 1935 1936 schp->pages[k] = alloc_pages(gfp_mask, order); 1937 if (!schp->pages[k]) 1938 goto out; 1939 1940 if (num == scatter_elem_sz_prev) { 1941 if (unlikely(ret_sz > scatter_elem_sz_prev)) { 1942 scatter_elem_sz = ret_sz; 1943 scatter_elem_sz_prev = ret_sz; 1944 } 1945 } 1946 1947 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp, 1948 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n", 1949 k, num, ret_sz)); 1950 } /* end of for loop */ 1951 1952 schp->page_order = order; 1953 schp->k_use_sg = k; 1954 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp, 1955 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n", 1956 k, rem_sz)); 1957 1958 schp->bufflen = blk_size; 1959 if (rem_sz > 0) /* must have failed */ 1960 return -ENOMEM; 1961 return 0; 1962 out: 1963 for (i = 0; i < k; i++) 1964 __free_pages(schp->pages[i], order); 1965 1966 if (--order >= 0) 1967 goto retry; 1968 1969 return -ENOMEM; 1970 } 1971 1972 static void 1973 sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp) 1974 { 1975 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 1976 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg)); 1977 if (schp->pages && schp->sglist_len > 0) { 1978 if (!schp->dio_in_use) { 1979 int k; 1980 1981 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) { 1982 SCSI_LOG_TIMEOUT(5, 1983 sg_printk(KERN_INFO, sfp->parentdp, 1984 "sg_remove_scat: k=%d, pg=0x%p\n", 1985 k, schp->pages[k])); 1986 __free_pages(schp->pages[k], schp->page_order); 1987 } 1988 1989 kfree(schp->pages); 1990 } 1991 } 1992 memset(schp, 0, sizeof (*schp)); 1993 } 1994 1995 static int 1996 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer) 1997 { 1998 Sg_scatter_hold *schp = &srp->data; 1999 int k, num; 2000 2001 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp, 2002 "sg_read_oxfer: num_read_xfer=%d\n", 2003 num_read_xfer)); 2004 if ((!outp) || (num_read_xfer <= 0)) 2005 return 0; 2006 2007 num = 1 << (PAGE_SHIFT + schp->page_order); 2008 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) { 2009 if (num > num_read_xfer) { 2010 if (copy_to_user(outp, page_address(schp->pages[k]), 2011 num_read_xfer)) 2012 return -EFAULT; 2013 break; 2014 } else { 2015 if (copy_to_user(outp, page_address(schp->pages[k]), 2016 num)) 2017 return -EFAULT; 2018 num_read_xfer -= num; 2019 if (num_read_xfer <= 0) 2020 break; 2021 outp += num; 2022 } 2023 } 2024 2025 return 0; 2026 } 2027 2028 static void 2029 sg_build_reserve(Sg_fd * sfp, int req_size) 2030 { 2031 Sg_scatter_hold *schp = &sfp->reserve; 2032 2033 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 2034 "sg_build_reserve: req_size=%d\n", req_size)); 2035 do { 2036 if (req_size < PAGE_SIZE) 2037 req_size = PAGE_SIZE; 2038 if (0 == sg_build_indirect(schp, sfp, req_size)) 2039 return; 2040 else 2041 sg_remove_scat(sfp, schp); 2042 req_size >>= 1; /* divide by 2 */ 2043 } while (req_size > (PAGE_SIZE / 2)); 2044 } 2045 2046 static void 2047 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size) 2048 { 2049 Sg_scatter_hold *req_schp = &srp->data; 2050 Sg_scatter_hold *rsv_schp = &sfp->reserve; 2051 int k, num, rem; 2052 2053 srp->res_used = 1; 2054 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 2055 "sg_link_reserve: size=%d\n", size)); 2056 rem = size; 2057 2058 num = 1 << (PAGE_SHIFT + rsv_schp->page_order); 2059 for (k = 0; k < rsv_schp->k_use_sg; k++) { 2060 if (rem <= num) { 2061 req_schp->k_use_sg = k + 1; 2062 req_schp->sglist_len = rsv_schp->sglist_len; 2063 req_schp->pages = rsv_schp->pages; 2064 2065 req_schp->bufflen = size; 2066 req_schp->page_order = rsv_schp->page_order; 2067 break; 2068 } else 2069 rem -= num; 2070 } 2071 2072 if (k >= rsv_schp->k_use_sg) 2073 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp, 2074 "sg_link_reserve: BAD size\n")); 2075 } 2076 2077 static void 2078 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp) 2079 { 2080 Sg_scatter_hold *req_schp = &srp->data; 2081 2082 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp, 2083 "sg_unlink_reserve: req->k_use_sg=%d\n", 2084 (int) req_schp->k_use_sg)); 2085 req_schp->k_use_sg = 0; 2086 req_schp->bufflen = 0; 2087 req_schp->pages = NULL; 2088 req_schp->page_order = 0; 2089 req_schp->sglist_len = 0; 2090 srp->res_used = 0; 2091 /* Called without mutex lock to avoid deadlock */ 2092 sfp->res_in_use = 0; 2093 } 2094 2095 static Sg_request * 2096 sg_get_rq_mark(Sg_fd * sfp, int pack_id) 2097 { 2098 Sg_request *resp; 2099 unsigned long iflags; 2100 2101 write_lock_irqsave(&sfp->rq_list_lock, iflags); 2102 list_for_each_entry(resp, &sfp->rq_list, entry) { 2103 /* look for requests that are ready + not SG_IO owned */ 2104 if ((1 == resp->done) && (!resp->sg_io_owned) && 2105 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) { 2106 resp->done = 2; /* guard against other readers */ 2107 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2108 return resp; 2109 } 2110 } 2111 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2112 return NULL; 2113 } 2114 2115 /* always adds to end of list */ 2116 static Sg_request * 2117 sg_add_request(Sg_fd * sfp) 2118 { 2119 int k; 2120 unsigned long iflags; 2121 Sg_request *rp = sfp->req_arr; 2122 2123 write_lock_irqsave(&sfp->rq_list_lock, iflags); 2124 if (!list_empty(&sfp->rq_list)) { 2125 if (!sfp->cmd_q) 2126 goto out_unlock; 2127 2128 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) { 2129 if (!rp->parentfp) 2130 break; 2131 } 2132 if (k >= SG_MAX_QUEUE) 2133 goto out_unlock; 2134 } 2135 memset(rp, 0, sizeof (Sg_request)); 2136 rp->parentfp = sfp; 2137 rp->header.duration = jiffies_to_msecs(jiffies); 2138 list_add_tail(&rp->entry, &sfp->rq_list); 2139 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2140 return rp; 2141 out_unlock: 2142 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2143 return NULL; 2144 } 2145 2146 /* Return of 1 for found; 0 for not found */ 2147 static int 2148 sg_remove_request(Sg_fd * sfp, Sg_request * srp) 2149 { 2150 unsigned long iflags; 2151 int res = 0; 2152 2153 if (!sfp || !srp || list_empty(&sfp->rq_list)) 2154 return res; 2155 write_lock_irqsave(&sfp->rq_list_lock, iflags); 2156 if (!list_empty(&srp->entry)) { 2157 list_del(&srp->entry); 2158 srp->parentfp = NULL; 2159 res = 1; 2160 } 2161 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2162 return res; 2163 } 2164 2165 static Sg_fd * 2166 sg_add_sfp(Sg_device * sdp) 2167 { 2168 Sg_fd *sfp; 2169 unsigned long iflags; 2170 int bufflen; 2171 2172 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN); 2173 if (!sfp) 2174 return ERR_PTR(-ENOMEM); 2175 2176 init_waitqueue_head(&sfp->read_wait); 2177 rwlock_init(&sfp->rq_list_lock); 2178 INIT_LIST_HEAD(&sfp->rq_list); 2179 kref_init(&sfp->f_ref); 2180 mutex_init(&sfp->f_mutex); 2181 sfp->timeout = SG_DEFAULT_TIMEOUT; 2182 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER; 2183 sfp->force_packid = SG_DEF_FORCE_PACK_ID; 2184 sfp->cmd_q = SG_DEF_COMMAND_Q; 2185 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN; 2186 sfp->parentdp = sdp; 2187 write_lock_irqsave(&sdp->sfd_lock, iflags); 2188 if (atomic_read(&sdp->detaching)) { 2189 write_unlock_irqrestore(&sdp->sfd_lock, iflags); 2190 kfree(sfp); 2191 return ERR_PTR(-ENODEV); 2192 } 2193 list_add_tail(&sfp->sfd_siblings, &sdp->sfds); 2194 write_unlock_irqrestore(&sdp->sfd_lock, iflags); 2195 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 2196 "sg_add_sfp: sfp=0x%p\n", sfp)); 2197 if (unlikely(sg_big_buff != def_reserved_size)) 2198 sg_big_buff = def_reserved_size; 2199 2200 bufflen = min_t(int, sg_big_buff, 2201 max_sectors_bytes(sdp->device->request_queue)); 2202 sg_build_reserve(sfp, bufflen); 2203 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 2204 "sg_add_sfp: bufflen=%d, k_use_sg=%d\n", 2205 sfp->reserve.bufflen, 2206 sfp->reserve.k_use_sg)); 2207 2208 kref_get(&sdp->d_ref); 2209 __module_get(THIS_MODULE); 2210 return sfp; 2211 } 2212 2213 static void 2214 sg_remove_sfp_usercontext(struct work_struct *work) 2215 { 2216 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work); 2217 struct sg_device *sdp = sfp->parentdp; 2218 Sg_request *srp; 2219 unsigned long iflags; 2220 2221 /* Cleanup any responses which were never read(). */ 2222 write_lock_irqsave(&sfp->rq_list_lock, iflags); 2223 while (!list_empty(&sfp->rq_list)) { 2224 srp = list_first_entry(&sfp->rq_list, Sg_request, entry); 2225 sg_finish_rem_req(srp); 2226 list_del(&srp->entry); 2227 srp->parentfp = NULL; 2228 } 2229 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2230 2231 if (sfp->reserve.bufflen > 0) { 2232 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp, 2233 "sg_remove_sfp: bufflen=%d, k_use_sg=%d\n", 2234 (int) sfp->reserve.bufflen, 2235 (int) sfp->reserve.k_use_sg)); 2236 sg_remove_scat(sfp, &sfp->reserve); 2237 } 2238 2239 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp, 2240 "sg_remove_sfp: sfp=0x%p\n", sfp)); 2241 kfree(sfp); 2242 2243 scsi_device_put(sdp->device); 2244 kref_put(&sdp->d_ref, sg_device_destroy); 2245 module_put(THIS_MODULE); 2246 } 2247 2248 static void 2249 sg_remove_sfp(struct kref *kref) 2250 { 2251 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref); 2252 struct sg_device *sdp = sfp->parentdp; 2253 unsigned long iflags; 2254 2255 write_lock_irqsave(&sdp->sfd_lock, iflags); 2256 list_del(&sfp->sfd_siblings); 2257 write_unlock_irqrestore(&sdp->sfd_lock, iflags); 2258 2259 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext); 2260 schedule_work(&sfp->ew.work); 2261 } 2262 2263 #ifdef CONFIG_SCSI_PROC_FS 2264 static int 2265 sg_idr_max_id(int id, void *p, void *data) 2266 { 2267 int *k = data; 2268 2269 if (*k < id) 2270 *k = id; 2271 2272 return 0; 2273 } 2274 2275 static int 2276 sg_last_dev(void) 2277 { 2278 int k = -1; 2279 unsigned long iflags; 2280 2281 read_lock_irqsave(&sg_index_lock, iflags); 2282 idr_for_each(&sg_index_idr, sg_idr_max_id, &k); 2283 read_unlock_irqrestore(&sg_index_lock, iflags); 2284 return k + 1; /* origin 1 */ 2285 } 2286 #endif 2287 2288 /* must be called with sg_index_lock held */ 2289 static Sg_device *sg_lookup_dev(int dev) 2290 { 2291 return idr_find(&sg_index_idr, dev); 2292 } 2293 2294 static Sg_device * 2295 sg_get_dev(int dev) 2296 { 2297 struct sg_device *sdp; 2298 unsigned long flags; 2299 2300 read_lock_irqsave(&sg_index_lock, flags); 2301 sdp = sg_lookup_dev(dev); 2302 if (!sdp) 2303 sdp = ERR_PTR(-ENXIO); 2304 else if (atomic_read(&sdp->detaching)) { 2305 /* If sdp->detaching, then the refcount may already be 0, in 2306 * which case it would be a bug to do kref_get(). 2307 */ 2308 sdp = ERR_PTR(-ENODEV); 2309 } else 2310 kref_get(&sdp->d_ref); 2311 read_unlock_irqrestore(&sg_index_lock, flags); 2312 2313 return sdp; 2314 } 2315 2316 #ifdef CONFIG_SCSI_PROC_FS 2317 static int sg_proc_seq_show_int(struct seq_file *s, void *v); 2318 2319 static int sg_proc_single_open_adio(struct inode *inode, struct file *file); 2320 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer, 2321 size_t count, loff_t *off); 2322 static const struct proc_ops adio_proc_ops = { 2323 .proc_open = sg_proc_single_open_adio, 2324 .proc_read = seq_read, 2325 .proc_lseek = seq_lseek, 2326 .proc_write = sg_proc_write_adio, 2327 .proc_release = single_release, 2328 }; 2329 2330 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file); 2331 static ssize_t sg_proc_write_dressz(struct file *filp, 2332 const char __user *buffer, size_t count, loff_t *off); 2333 static const struct proc_ops dressz_proc_ops = { 2334 .proc_open = sg_proc_single_open_dressz, 2335 .proc_read = seq_read, 2336 .proc_lseek = seq_lseek, 2337 .proc_write = sg_proc_write_dressz, 2338 .proc_release = single_release, 2339 }; 2340 2341 static int sg_proc_seq_show_version(struct seq_file *s, void *v); 2342 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v); 2343 static int sg_proc_seq_show_dev(struct seq_file *s, void *v); 2344 static void * dev_seq_start(struct seq_file *s, loff_t *pos); 2345 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos); 2346 static void dev_seq_stop(struct seq_file *s, void *v); 2347 static const struct seq_operations dev_seq_ops = { 2348 .start = dev_seq_start, 2349 .next = dev_seq_next, 2350 .stop = dev_seq_stop, 2351 .show = sg_proc_seq_show_dev, 2352 }; 2353 2354 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v); 2355 static const struct seq_operations devstrs_seq_ops = { 2356 .start = dev_seq_start, 2357 .next = dev_seq_next, 2358 .stop = dev_seq_stop, 2359 .show = sg_proc_seq_show_devstrs, 2360 }; 2361 2362 static int sg_proc_seq_show_debug(struct seq_file *s, void *v); 2363 static const struct seq_operations debug_seq_ops = { 2364 .start = dev_seq_start, 2365 .next = dev_seq_next, 2366 .stop = dev_seq_stop, 2367 .show = sg_proc_seq_show_debug, 2368 }; 2369 2370 static int 2371 sg_proc_init(void) 2372 { 2373 struct proc_dir_entry *p; 2374 2375 p = proc_mkdir("scsi/sg", NULL); 2376 if (!p) 2377 return 1; 2378 2379 proc_create("allow_dio", S_IRUGO | S_IWUSR, p, &adio_proc_ops); 2380 proc_create_seq("debug", S_IRUGO, p, &debug_seq_ops); 2381 proc_create("def_reserved_size", S_IRUGO | S_IWUSR, p, &dressz_proc_ops); 2382 proc_create_single("device_hdr", S_IRUGO, p, sg_proc_seq_show_devhdr); 2383 proc_create_seq("devices", S_IRUGO, p, &dev_seq_ops); 2384 proc_create_seq("device_strs", S_IRUGO, p, &devstrs_seq_ops); 2385 proc_create_single("version", S_IRUGO, p, sg_proc_seq_show_version); 2386 return 0; 2387 } 2388 2389 2390 static int sg_proc_seq_show_int(struct seq_file *s, void *v) 2391 { 2392 seq_printf(s, "%d\n", *((int *)s->private)); 2393 return 0; 2394 } 2395 2396 static int sg_proc_single_open_adio(struct inode *inode, struct file *file) 2397 { 2398 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio); 2399 } 2400 2401 static ssize_t 2402 sg_proc_write_adio(struct file *filp, const char __user *buffer, 2403 size_t count, loff_t *off) 2404 { 2405 int err; 2406 unsigned long num; 2407 2408 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) 2409 return -EACCES; 2410 err = kstrtoul_from_user(buffer, count, 0, &num); 2411 if (err) 2412 return err; 2413 sg_allow_dio = num ? 1 : 0; 2414 return count; 2415 } 2416 2417 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file) 2418 { 2419 return single_open(file, sg_proc_seq_show_int, &sg_big_buff); 2420 } 2421 2422 static ssize_t 2423 sg_proc_write_dressz(struct file *filp, const char __user *buffer, 2424 size_t count, loff_t *off) 2425 { 2426 int err; 2427 unsigned long k = ULONG_MAX; 2428 2429 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) 2430 return -EACCES; 2431 2432 err = kstrtoul_from_user(buffer, count, 0, &k); 2433 if (err) 2434 return err; 2435 if (k <= 1048576) { /* limit "big buff" to 1 MB */ 2436 sg_big_buff = k; 2437 return count; 2438 } 2439 return -ERANGE; 2440 } 2441 2442 static int sg_proc_seq_show_version(struct seq_file *s, void *v) 2443 { 2444 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR, 2445 sg_version_date); 2446 return 0; 2447 } 2448 2449 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v) 2450 { 2451 seq_puts(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n"); 2452 return 0; 2453 } 2454 2455 struct sg_proc_deviter { 2456 loff_t index; 2457 size_t max; 2458 }; 2459 2460 static void * dev_seq_start(struct seq_file *s, loff_t *pos) 2461 { 2462 struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL); 2463 2464 s->private = it; 2465 if (! it) 2466 return NULL; 2467 2468 it->index = *pos; 2469 it->max = sg_last_dev(); 2470 if (it->index >= it->max) 2471 return NULL; 2472 return it; 2473 } 2474 2475 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos) 2476 { 2477 struct sg_proc_deviter * it = s->private; 2478 2479 *pos = ++it->index; 2480 return (it->index < it->max) ? it : NULL; 2481 } 2482 2483 static void dev_seq_stop(struct seq_file *s, void *v) 2484 { 2485 kfree(s->private); 2486 } 2487 2488 static int sg_proc_seq_show_dev(struct seq_file *s, void *v) 2489 { 2490 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v; 2491 Sg_device *sdp; 2492 struct scsi_device *scsidp; 2493 unsigned long iflags; 2494 2495 read_lock_irqsave(&sg_index_lock, iflags); 2496 sdp = it ? sg_lookup_dev(it->index) : NULL; 2497 if ((NULL == sdp) || (NULL == sdp->device) || 2498 (atomic_read(&sdp->detaching))) 2499 seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n"); 2500 else { 2501 scsidp = sdp->device; 2502 seq_printf(s, "%d\t%d\t%d\t%llu\t%d\t%d\t%d\t%d\t%d\n", 2503 scsidp->host->host_no, scsidp->channel, 2504 scsidp->id, scsidp->lun, (int) scsidp->type, 2505 1, 2506 (int) scsidp->queue_depth, 2507 (int) scsi_device_busy(scsidp), 2508 (int) scsi_device_online(scsidp)); 2509 } 2510 read_unlock_irqrestore(&sg_index_lock, iflags); 2511 return 0; 2512 } 2513 2514 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v) 2515 { 2516 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v; 2517 Sg_device *sdp; 2518 struct scsi_device *scsidp; 2519 unsigned long iflags; 2520 2521 read_lock_irqsave(&sg_index_lock, iflags); 2522 sdp = it ? sg_lookup_dev(it->index) : NULL; 2523 scsidp = sdp ? sdp->device : NULL; 2524 if (sdp && scsidp && (!atomic_read(&sdp->detaching))) 2525 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n", 2526 scsidp->vendor, scsidp->model, scsidp->rev); 2527 else 2528 seq_puts(s, "<no active device>\n"); 2529 read_unlock_irqrestore(&sg_index_lock, iflags); 2530 return 0; 2531 } 2532 2533 /* must be called while holding sg_index_lock */ 2534 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp) 2535 { 2536 int k, new_interface, blen, usg; 2537 Sg_request *srp; 2538 Sg_fd *fp; 2539 const sg_io_hdr_t *hp; 2540 const char * cp; 2541 unsigned int ms; 2542 2543 k = 0; 2544 list_for_each_entry(fp, &sdp->sfds, sfd_siblings) { 2545 k++; 2546 read_lock(&fp->rq_list_lock); /* irqs already disabled */ 2547 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d " 2548 "(res)sgat=%d low_dma=%d\n", k, 2549 jiffies_to_msecs(fp->timeout), 2550 fp->reserve.bufflen, 2551 (int) fp->reserve.k_use_sg, 0); 2552 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n", 2553 (int) fp->cmd_q, (int) fp->force_packid, 2554 (int) fp->keep_orphan); 2555 list_for_each_entry(srp, &fp->rq_list, entry) { 2556 hp = &srp->header; 2557 new_interface = (hp->interface_id == '\0') ? 0 : 1; 2558 if (srp->res_used) { 2559 if (new_interface && 2560 (SG_FLAG_MMAP_IO & hp->flags)) 2561 cp = " mmap>> "; 2562 else 2563 cp = " rb>> "; 2564 } else { 2565 if (SG_INFO_DIRECT_IO_MASK & hp->info) 2566 cp = " dio>> "; 2567 else 2568 cp = " "; 2569 } 2570 seq_puts(s, cp); 2571 blen = srp->data.bufflen; 2572 usg = srp->data.k_use_sg; 2573 seq_puts(s, srp->done ? 2574 ((1 == srp->done) ? "rcv:" : "fin:") 2575 : "act:"); 2576 seq_printf(s, " id=%d blen=%d", 2577 srp->header.pack_id, blen); 2578 if (srp->done) 2579 seq_printf(s, " dur=%d", hp->duration); 2580 else { 2581 ms = jiffies_to_msecs(jiffies); 2582 seq_printf(s, " t_o/elap=%d/%d", 2583 (new_interface ? hp->timeout : 2584 jiffies_to_msecs(fp->timeout)), 2585 (ms > hp->duration ? ms - hp->duration : 0)); 2586 } 2587 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg, 2588 (int) srp->data.cmd_opcode); 2589 } 2590 if (list_empty(&fp->rq_list)) 2591 seq_puts(s, " No requests active\n"); 2592 read_unlock(&fp->rq_list_lock); 2593 } 2594 } 2595 2596 static int sg_proc_seq_show_debug(struct seq_file *s, void *v) 2597 { 2598 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v; 2599 Sg_device *sdp; 2600 unsigned long iflags; 2601 2602 if (it && (0 == it->index)) 2603 seq_printf(s, "max_active_device=%d def_reserved_size=%d\n", 2604 (int)it->max, sg_big_buff); 2605 2606 read_lock_irqsave(&sg_index_lock, iflags); 2607 sdp = it ? sg_lookup_dev(it->index) : NULL; 2608 if (NULL == sdp) 2609 goto skip; 2610 read_lock(&sdp->sfd_lock); 2611 if (!list_empty(&sdp->sfds)) { 2612 seq_printf(s, " >>> device=%s ", sdp->name); 2613 if (atomic_read(&sdp->detaching)) 2614 seq_puts(s, "detaching pending close "); 2615 else if (sdp->device) { 2616 struct scsi_device *scsidp = sdp->device; 2617 2618 seq_printf(s, "%d:%d:%d:%llu em=%d", 2619 scsidp->host->host_no, 2620 scsidp->channel, scsidp->id, 2621 scsidp->lun, 2622 scsidp->host->hostt->emulated); 2623 } 2624 seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n", 2625 sdp->sg_tablesize, sdp->exclude, sdp->open_cnt); 2626 sg_proc_debug_helper(s, sdp); 2627 } 2628 read_unlock(&sdp->sfd_lock); 2629 skip: 2630 read_unlock_irqrestore(&sg_index_lock, iflags); 2631 return 0; 2632 } 2633 2634 #endif /* CONFIG_SCSI_PROC_FS */ 2635 2636 module_init(init_sg); 2637 module_exit(exit_sg); 2638