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 struct gendisk *disk; 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, \ 206 (sdp)->disk->disk_name, fmt, ##a) 207 208 /* 209 * The SCSI interfaces that use read() and write() as an asynchronous variant of 210 * ioctl(..., SG_IO, ...) are fundamentally unsafe, since there are lots of ways 211 * to trigger read() and write() calls from various contexts with elevated 212 * privileges. This can lead to kernel memory corruption (e.g. if these 213 * interfaces are called through splice()) and privilege escalation inside 214 * userspace (e.g. if a process with access to such a device passes a file 215 * descriptor to a SUID binary as stdin/stdout/stderr). 216 * 217 * This function provides protection for the legacy API by restricting the 218 * calling context. 219 */ 220 static int sg_check_file_access(struct file *filp, const char *caller) 221 { 222 if (filp->f_cred != current_real_cred()) { 223 pr_err_once("%s: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n", 224 caller, task_tgid_vnr(current), current->comm); 225 return -EPERM; 226 } 227 if (uaccess_kernel()) { 228 pr_err_once("%s: process %d (%s) called from kernel context, this is not allowed.\n", 229 caller, task_tgid_vnr(current), current->comm); 230 return -EACCES; 231 } 232 return 0; 233 } 234 235 static int sg_allow_access(struct file *filp, unsigned char *cmd) 236 { 237 struct sg_fd *sfp = filp->private_data; 238 239 if (sfp->parentdp->device->type == TYPE_SCANNER) 240 return 0; 241 242 return blk_verify_command(cmd, filp->f_mode); 243 } 244 245 static int 246 open_wait(Sg_device *sdp, int flags) 247 { 248 int retval = 0; 249 250 if (flags & O_EXCL) { 251 while (sdp->open_cnt > 0) { 252 mutex_unlock(&sdp->open_rel_lock); 253 retval = wait_event_interruptible(sdp->open_wait, 254 (atomic_read(&sdp->detaching) || 255 !sdp->open_cnt)); 256 mutex_lock(&sdp->open_rel_lock); 257 258 if (retval) /* -ERESTARTSYS */ 259 return retval; 260 if (atomic_read(&sdp->detaching)) 261 return -ENODEV; 262 } 263 } else { 264 while (sdp->exclude) { 265 mutex_unlock(&sdp->open_rel_lock); 266 retval = wait_event_interruptible(sdp->open_wait, 267 (atomic_read(&sdp->detaching) || 268 !sdp->exclude)); 269 mutex_lock(&sdp->open_rel_lock); 270 271 if (retval) /* -ERESTARTSYS */ 272 return retval; 273 if (atomic_read(&sdp->detaching)) 274 return -ENODEV; 275 } 276 } 277 278 return retval; 279 } 280 281 /* Returns 0 on success, else a negated errno value */ 282 static int 283 sg_open(struct inode *inode, struct file *filp) 284 { 285 int dev = iminor(inode); 286 int flags = filp->f_flags; 287 struct request_queue *q; 288 Sg_device *sdp; 289 Sg_fd *sfp; 290 int retval; 291 292 nonseekable_open(inode, filp); 293 if ((flags & O_EXCL) && (O_RDONLY == (flags & O_ACCMODE))) 294 return -EPERM; /* Can't lock it with read only access */ 295 sdp = sg_get_dev(dev); 296 if (IS_ERR(sdp)) 297 return PTR_ERR(sdp); 298 299 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 300 "sg_open: flags=0x%x\n", flags)); 301 302 /* This driver's module count bumped by fops_get in <linux/fs.h> */ 303 /* Prevent the device driver from vanishing while we sleep */ 304 retval = scsi_device_get(sdp->device); 305 if (retval) 306 goto sg_put; 307 308 retval = scsi_autopm_get_device(sdp->device); 309 if (retval) 310 goto sdp_put; 311 312 /* scsi_block_when_processing_errors() may block so bypass 313 * check if O_NONBLOCK. Permits SCSI commands to be issued 314 * during error recovery. Tread carefully. */ 315 if (!((flags & O_NONBLOCK) || 316 scsi_block_when_processing_errors(sdp->device))) { 317 retval = -ENXIO; 318 /* we are in error recovery for this device */ 319 goto error_out; 320 } 321 322 mutex_lock(&sdp->open_rel_lock); 323 if (flags & O_NONBLOCK) { 324 if (flags & O_EXCL) { 325 if (sdp->open_cnt > 0) { 326 retval = -EBUSY; 327 goto error_mutex_locked; 328 } 329 } else { 330 if (sdp->exclude) { 331 retval = -EBUSY; 332 goto error_mutex_locked; 333 } 334 } 335 } else { 336 retval = open_wait(sdp, flags); 337 if (retval) /* -ERESTARTSYS or -ENODEV */ 338 goto error_mutex_locked; 339 } 340 341 /* N.B. at this point we are holding the open_rel_lock */ 342 if (flags & O_EXCL) 343 sdp->exclude = true; 344 345 if (sdp->open_cnt < 1) { /* no existing opens */ 346 sdp->sgdebug = 0; 347 q = sdp->device->request_queue; 348 sdp->sg_tablesize = queue_max_segments(q); 349 } 350 sfp = sg_add_sfp(sdp); 351 if (IS_ERR(sfp)) { 352 retval = PTR_ERR(sfp); 353 goto out_undo; 354 } 355 356 filp->private_data = sfp; 357 sdp->open_cnt++; 358 mutex_unlock(&sdp->open_rel_lock); 359 360 retval = 0; 361 sg_put: 362 kref_put(&sdp->d_ref, sg_device_destroy); 363 return retval; 364 365 out_undo: 366 if (flags & O_EXCL) { 367 sdp->exclude = false; /* undo if error */ 368 wake_up_interruptible(&sdp->open_wait); 369 } 370 error_mutex_locked: 371 mutex_unlock(&sdp->open_rel_lock); 372 error_out: 373 scsi_autopm_put_device(sdp->device); 374 sdp_put: 375 scsi_device_put(sdp->device); 376 goto sg_put; 377 } 378 379 /* Release resources associated with a successful sg_open() 380 * Returns 0 on success, else a negated errno value */ 381 static int 382 sg_release(struct inode *inode, struct file *filp) 383 { 384 Sg_device *sdp; 385 Sg_fd *sfp; 386 387 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 388 return -ENXIO; 389 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, "sg_release\n")); 390 391 mutex_lock(&sdp->open_rel_lock); 392 scsi_autopm_put_device(sdp->device); 393 kref_put(&sfp->f_ref, sg_remove_sfp); 394 sdp->open_cnt--; 395 396 /* possibly many open()s waiting on exlude clearing, start many; 397 * only open(O_EXCL)s wait on 0==open_cnt so only start one */ 398 if (sdp->exclude) { 399 sdp->exclude = false; 400 wake_up_interruptible_all(&sdp->open_wait); 401 } else if (0 == sdp->open_cnt) { 402 wake_up_interruptible(&sdp->open_wait); 403 } 404 mutex_unlock(&sdp->open_rel_lock); 405 return 0; 406 } 407 408 static ssize_t 409 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos) 410 { 411 Sg_device *sdp; 412 Sg_fd *sfp; 413 Sg_request *srp; 414 int req_pack_id = -1; 415 sg_io_hdr_t *hp; 416 struct sg_header *old_hdr = NULL; 417 int retval = 0; 418 419 /* 420 * This could cause a response to be stranded. Close the associated 421 * file descriptor to free up any resources being held. 422 */ 423 retval = sg_check_file_access(filp, __func__); 424 if (retval) 425 return retval; 426 427 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 428 return -ENXIO; 429 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 430 "sg_read: count=%d\n", (int) count)); 431 432 if (sfp->force_packid && (count >= SZ_SG_HEADER)) { 433 old_hdr = memdup_user(buf, SZ_SG_HEADER); 434 if (IS_ERR(old_hdr)) 435 return PTR_ERR(old_hdr); 436 if (old_hdr->reply_len < 0) { 437 if (count >= SZ_SG_IO_HDR) { 438 /* 439 * This is stupid. 440 * 441 * We're copying the whole sg_io_hdr_t from user 442 * space just to get the 'pack_id' field. But the 443 * field is at different offsets for the compat 444 * case, so we'll use "get_sg_io_hdr()" to copy 445 * the whole thing and convert it. 446 * 447 * We could do something like just calculating the 448 * offset based of 'in_compat_syscall()', but the 449 * 'compat_sg_io_hdr' definition is in the wrong 450 * place for that. 451 */ 452 sg_io_hdr_t *new_hdr; 453 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL); 454 if (!new_hdr) { 455 retval = -ENOMEM; 456 goto free_old_hdr; 457 } 458 retval = get_sg_io_hdr(new_hdr, buf); 459 req_pack_id = new_hdr->pack_id; 460 kfree(new_hdr); 461 if (retval) { 462 retval = -EFAULT; 463 goto free_old_hdr; 464 } 465 } 466 } else 467 req_pack_id = old_hdr->pack_id; 468 } 469 srp = sg_get_rq_mark(sfp, req_pack_id); 470 if (!srp) { /* now wait on packet to arrive */ 471 if (atomic_read(&sdp->detaching)) { 472 retval = -ENODEV; 473 goto free_old_hdr; 474 } 475 if (filp->f_flags & O_NONBLOCK) { 476 retval = -EAGAIN; 477 goto free_old_hdr; 478 } 479 retval = wait_event_interruptible(sfp->read_wait, 480 (atomic_read(&sdp->detaching) || 481 (srp = sg_get_rq_mark(sfp, req_pack_id)))); 482 if (atomic_read(&sdp->detaching)) { 483 retval = -ENODEV; 484 goto free_old_hdr; 485 } 486 if (retval) { 487 /* -ERESTARTSYS as signal hit process */ 488 goto free_old_hdr; 489 } 490 } 491 if (srp->header.interface_id != '\0') { 492 retval = sg_new_read(sfp, buf, count, srp); 493 goto free_old_hdr; 494 } 495 496 hp = &srp->header; 497 if (old_hdr == NULL) { 498 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL); 499 if (! old_hdr) { 500 retval = -ENOMEM; 501 goto free_old_hdr; 502 } 503 } 504 memset(old_hdr, 0, SZ_SG_HEADER); 505 old_hdr->reply_len = (int) hp->timeout; 506 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */ 507 old_hdr->pack_id = hp->pack_id; 508 old_hdr->twelve_byte = 509 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0; 510 old_hdr->target_status = hp->masked_status; 511 old_hdr->host_status = hp->host_status; 512 old_hdr->driver_status = hp->driver_status; 513 if ((CHECK_CONDITION & hp->masked_status) || 514 (DRIVER_SENSE & hp->driver_status)) 515 memcpy(old_hdr->sense_buffer, srp->sense_b, 516 sizeof (old_hdr->sense_buffer)); 517 switch (hp->host_status) { 518 /* This setup of 'result' is for backward compatibility and is best 519 ignored by the user who should use target, host + driver status */ 520 case DID_OK: 521 case DID_PASSTHROUGH: 522 case DID_SOFT_ERROR: 523 old_hdr->result = 0; 524 break; 525 case DID_NO_CONNECT: 526 case DID_BUS_BUSY: 527 case DID_TIME_OUT: 528 old_hdr->result = EBUSY; 529 break; 530 case DID_BAD_TARGET: 531 case DID_ABORT: 532 case DID_PARITY: 533 case DID_RESET: 534 case DID_BAD_INTR: 535 old_hdr->result = EIO; 536 break; 537 case DID_ERROR: 538 old_hdr->result = (srp->sense_b[0] == 0 && 539 hp->masked_status == GOOD) ? 0 : EIO; 540 break; 541 default: 542 old_hdr->result = EIO; 543 break; 544 } 545 546 /* Now copy the result back to the user buffer. */ 547 if (count >= SZ_SG_HEADER) { 548 if (copy_to_user(buf, old_hdr, SZ_SG_HEADER)) { 549 retval = -EFAULT; 550 goto free_old_hdr; 551 } 552 buf += SZ_SG_HEADER; 553 if (count > old_hdr->reply_len) 554 count = old_hdr->reply_len; 555 if (count > SZ_SG_HEADER) { 556 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) { 557 retval = -EFAULT; 558 goto free_old_hdr; 559 } 560 } 561 } else 562 count = (old_hdr->result == 0) ? 0 : -EIO; 563 sg_finish_rem_req(srp); 564 sg_remove_request(sfp, srp); 565 retval = count; 566 free_old_hdr: 567 kfree(old_hdr); 568 return retval; 569 } 570 571 static ssize_t 572 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp) 573 { 574 sg_io_hdr_t *hp = &srp->header; 575 int err = 0, err2; 576 int len; 577 578 if (count < SZ_SG_IO_HDR) { 579 err = -EINVAL; 580 goto err_out; 581 } 582 hp->sb_len_wr = 0; 583 if ((hp->mx_sb_len > 0) && hp->sbp) { 584 if ((CHECK_CONDITION & hp->masked_status) || 585 (DRIVER_SENSE & hp->driver_status)) { 586 int sb_len = SCSI_SENSE_BUFFERSIZE; 587 sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len; 588 len = 8 + (int) srp->sense_b[7]; /* Additional sense length field */ 589 len = (len > sb_len) ? sb_len : len; 590 if (copy_to_user(hp->sbp, srp->sense_b, len)) { 591 err = -EFAULT; 592 goto err_out; 593 } 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 return -EFAULT; 698 /* 699 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV, 700 * but is is possible that the app intended SG_DXFER_TO_DEV, because there 701 * is a non-zero input_size, so emit a warning. 702 */ 703 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) { 704 printk_ratelimited(KERN_WARNING 705 "sg_write: data in/out %d/%d bytes " 706 "for SCSI command 0x%x-- guessing " 707 "data in;\n program %s not setting " 708 "count and/or reply_len properly\n", 709 old_hdr.reply_len - (int)SZ_SG_HEADER, 710 input_size, (unsigned int) cmnd[0], 711 current->comm); 712 } 713 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking); 714 return (k < 0) ? k : count; 715 } 716 717 static ssize_t 718 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf, 719 size_t count, int blocking, int read_only, int sg_io_owned, 720 Sg_request **o_srp) 721 { 722 int k; 723 Sg_request *srp; 724 sg_io_hdr_t *hp; 725 unsigned char cmnd[SG_MAX_CDB_SIZE]; 726 int timeout; 727 unsigned long ul_timeout; 728 729 if (count < SZ_SG_IO_HDR) 730 return -EINVAL; 731 732 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */ 733 if (!(srp = sg_add_request(sfp))) { 734 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp, 735 "sg_new_write: queue full\n")); 736 return -EDOM; 737 } 738 srp->sg_io_owned = sg_io_owned; 739 hp = &srp->header; 740 if (get_sg_io_hdr(hp, buf)) { 741 sg_remove_request(sfp, srp); 742 return -EFAULT; 743 } 744 if (hp->interface_id != 'S') { 745 sg_remove_request(sfp, srp); 746 return -ENOSYS; 747 } 748 if (hp->flags & SG_FLAG_MMAP_IO) { 749 if (hp->dxfer_len > sfp->reserve.bufflen) { 750 sg_remove_request(sfp, srp); 751 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */ 752 } 753 if (hp->flags & SG_FLAG_DIRECT_IO) { 754 sg_remove_request(sfp, srp); 755 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */ 756 } 757 if (sfp->res_in_use) { 758 sg_remove_request(sfp, srp); 759 return -EBUSY; /* reserve buffer already being used */ 760 } 761 } 762 ul_timeout = msecs_to_jiffies(srp->header.timeout); 763 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX; 764 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) { 765 sg_remove_request(sfp, srp); 766 return -EMSGSIZE; 767 } 768 if (copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) { 769 sg_remove_request(sfp, srp); 770 return -EFAULT; 771 } 772 if (read_only && sg_allow_access(file, cmnd)) { 773 sg_remove_request(sfp, srp); 774 return -EPERM; 775 } 776 k = sg_common_write(sfp, srp, cmnd, timeout, blocking); 777 if (k < 0) 778 return k; 779 if (o_srp) 780 *o_srp = srp; 781 return count; 782 } 783 784 static int 785 sg_common_write(Sg_fd * sfp, Sg_request * srp, 786 unsigned char *cmnd, int timeout, int blocking) 787 { 788 int k, at_head; 789 Sg_device *sdp = sfp->parentdp; 790 sg_io_hdr_t *hp = &srp->header; 791 792 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */ 793 hp->status = 0; 794 hp->masked_status = 0; 795 hp->msg_status = 0; 796 hp->info = 0; 797 hp->host_status = 0; 798 hp->driver_status = 0; 799 hp->resid = 0; 800 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 801 "sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n", 802 (int) cmnd[0], (int) hp->cmd_len)); 803 804 if (hp->dxfer_len >= SZ_256M) 805 return -EINVAL; 806 807 k = sg_start_req(srp, cmnd); 808 if (k) { 809 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp, 810 "sg_common_write: start_req err=%d\n", k)); 811 sg_finish_rem_req(srp); 812 sg_remove_request(sfp, srp); 813 return k; /* probably out of space --> ENOMEM */ 814 } 815 if (atomic_read(&sdp->detaching)) { 816 if (srp->bio) { 817 scsi_req_free_cmd(scsi_req(srp->rq)); 818 blk_put_request(srp->rq); 819 srp->rq = NULL; 820 } 821 822 sg_finish_rem_req(srp); 823 sg_remove_request(sfp, srp); 824 return -ENODEV; 825 } 826 827 hp->duration = jiffies_to_msecs(jiffies); 828 if (hp->interface_id != '\0' && /* v3 (or later) interface */ 829 (SG_FLAG_Q_AT_TAIL & hp->flags)) 830 at_head = 0; 831 else 832 at_head = 1; 833 834 srp->rq->timeout = timeout; 835 kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */ 836 blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk, 837 srp->rq, at_head, sg_rq_end_io); 838 return 0; 839 } 840 841 static int srp_done(Sg_fd *sfp, Sg_request *srp) 842 { 843 unsigned long flags; 844 int ret; 845 846 read_lock_irqsave(&sfp->rq_list_lock, flags); 847 ret = srp->done; 848 read_unlock_irqrestore(&sfp->rq_list_lock, flags); 849 return ret; 850 } 851 852 static int max_sectors_bytes(struct request_queue *q) 853 { 854 unsigned int max_sectors = queue_max_sectors(q); 855 856 max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9); 857 858 return max_sectors << 9; 859 } 860 861 static void 862 sg_fill_request_table(Sg_fd *sfp, sg_req_info_t *rinfo) 863 { 864 Sg_request *srp; 865 int val; 866 unsigned int ms; 867 868 val = 0; 869 list_for_each_entry(srp, &sfp->rq_list, entry) { 870 if (val >= SG_MAX_QUEUE) 871 break; 872 rinfo[val].req_state = srp->done + 1; 873 rinfo[val].problem = 874 srp->header.masked_status & 875 srp->header.host_status & 876 srp->header.driver_status; 877 if (srp->done) 878 rinfo[val].duration = 879 srp->header.duration; 880 else { 881 ms = jiffies_to_msecs(jiffies); 882 rinfo[val].duration = 883 (ms > srp->header.duration) ? 884 (ms - srp->header.duration) : 0; 885 } 886 rinfo[val].orphan = srp->orphan; 887 rinfo[val].sg_io_owned = srp->sg_io_owned; 888 rinfo[val].pack_id = srp->header.pack_id; 889 rinfo[val].usr_ptr = srp->header.usr_ptr; 890 val++; 891 } 892 } 893 894 #ifdef CONFIG_COMPAT 895 struct compat_sg_req_info { /* used by SG_GET_REQUEST_TABLE ioctl() */ 896 char req_state; 897 char orphan; 898 char sg_io_owned; 899 char problem; 900 int pack_id; 901 compat_uptr_t usr_ptr; 902 unsigned int duration; 903 int unused; 904 }; 905 906 static int put_compat_request_table(struct compat_sg_req_info __user *o, 907 struct sg_req_info *rinfo) 908 { 909 int i; 910 for (i = 0; i < SG_MAX_QUEUE; i++) { 911 if (copy_to_user(o + i, rinfo + i, offsetof(sg_req_info_t, usr_ptr)) || 912 put_user((uintptr_t)rinfo[i].usr_ptr, &o[i].usr_ptr) || 913 put_user(rinfo[i].duration, &o[i].duration) || 914 put_user(rinfo[i].unused, &o[i].unused)) 915 return -EFAULT; 916 } 917 return 0; 918 } 919 #endif 920 921 static long 922 sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg) 923 { 924 void __user *p = (void __user *)arg; 925 int __user *ip = p; 926 int result, val, read_only; 927 Sg_device *sdp; 928 Sg_fd *sfp; 929 Sg_request *srp; 930 unsigned long iflags; 931 932 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 933 return -ENXIO; 934 935 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 936 "sg_ioctl: cmd=0x%x\n", (int) cmd_in)); 937 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE)); 938 939 switch (cmd_in) { 940 case SG_IO: 941 if (atomic_read(&sdp->detaching)) 942 return -ENODEV; 943 if (!scsi_block_when_processing_errors(sdp->device)) 944 return -ENXIO; 945 result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR, 946 1, read_only, 1, &srp); 947 if (result < 0) 948 return result; 949 result = wait_event_interruptible(sfp->read_wait, 950 (srp_done(sfp, srp) || atomic_read(&sdp->detaching))); 951 if (atomic_read(&sdp->detaching)) 952 return -ENODEV; 953 write_lock_irq(&sfp->rq_list_lock); 954 if (srp->done) { 955 srp->done = 2; 956 write_unlock_irq(&sfp->rq_list_lock); 957 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp); 958 return (result < 0) ? result : 0; 959 } 960 srp->orphan = 1; 961 write_unlock_irq(&sfp->rq_list_lock); 962 return result; /* -ERESTARTSYS because signal hit process */ 963 case SG_SET_TIMEOUT: 964 result = get_user(val, ip); 965 if (result) 966 return result; 967 if (val < 0) 968 return -EIO; 969 if (val >= mult_frac((s64)INT_MAX, USER_HZ, HZ)) 970 val = min_t(s64, mult_frac((s64)INT_MAX, USER_HZ, HZ), 971 INT_MAX); 972 sfp->timeout_user = val; 973 sfp->timeout = mult_frac(val, HZ, USER_HZ); 974 975 return 0; 976 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */ 977 /* strange ..., for backward compatibility */ 978 return sfp->timeout_user; 979 case SG_SET_FORCE_LOW_DMA: 980 /* 981 * N.B. This ioctl never worked properly, but failed to 982 * return an error value. So returning '0' to keep compability 983 * with legacy applications. 984 */ 985 return 0; 986 case SG_GET_LOW_DMA: 987 return put_user((int) sdp->device->host->unchecked_isa_dma, ip); 988 case SG_GET_SCSI_ID: 989 { 990 sg_scsi_id_t v; 991 992 if (atomic_read(&sdp->detaching)) 993 return -ENODEV; 994 memset(&v, 0, sizeof(v)); 995 v.host_no = sdp->device->host->host_no; 996 v.channel = sdp->device->channel; 997 v.scsi_id = sdp->device->id; 998 v.lun = sdp->device->lun; 999 v.scsi_type = sdp->device->type; 1000 v.h_cmd_per_lun = sdp->device->host->cmd_per_lun; 1001 v.d_queue_depth = sdp->device->queue_depth; 1002 if (copy_to_user(p, &v, sizeof(sg_scsi_id_t))) 1003 return -EFAULT; 1004 return 0; 1005 } 1006 case SG_SET_FORCE_PACK_ID: 1007 result = get_user(val, ip); 1008 if (result) 1009 return result; 1010 sfp->force_packid = val ? 1 : 0; 1011 return 0; 1012 case SG_GET_PACK_ID: 1013 read_lock_irqsave(&sfp->rq_list_lock, iflags); 1014 list_for_each_entry(srp, &sfp->rq_list, entry) { 1015 if ((1 == srp->done) && (!srp->sg_io_owned)) { 1016 read_unlock_irqrestore(&sfp->rq_list_lock, 1017 iflags); 1018 return put_user(srp->header.pack_id, ip); 1019 } 1020 } 1021 read_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1022 return put_user(-1, ip); 1023 case SG_GET_NUM_WAITING: 1024 read_lock_irqsave(&sfp->rq_list_lock, iflags); 1025 val = 0; 1026 list_for_each_entry(srp, &sfp->rq_list, entry) { 1027 if ((1 == srp->done) && (!srp->sg_io_owned)) 1028 ++val; 1029 } 1030 read_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1031 return put_user(val, ip); 1032 case SG_GET_SG_TABLESIZE: 1033 return put_user(sdp->sg_tablesize, ip); 1034 case SG_SET_RESERVED_SIZE: 1035 result = get_user(val, ip); 1036 if (result) 1037 return result; 1038 if (val < 0) 1039 return -EINVAL; 1040 val = min_t(int, val, 1041 max_sectors_bytes(sdp->device->request_queue)); 1042 mutex_lock(&sfp->f_mutex); 1043 if (val != sfp->reserve.bufflen) { 1044 if (sfp->mmap_called || 1045 sfp->res_in_use) { 1046 mutex_unlock(&sfp->f_mutex); 1047 return -EBUSY; 1048 } 1049 1050 sg_remove_scat(sfp, &sfp->reserve); 1051 sg_build_reserve(sfp, val); 1052 } 1053 mutex_unlock(&sfp->f_mutex); 1054 return 0; 1055 case SG_GET_RESERVED_SIZE: 1056 val = min_t(int, sfp->reserve.bufflen, 1057 max_sectors_bytes(sdp->device->request_queue)); 1058 return put_user(val, ip); 1059 case SG_SET_COMMAND_Q: 1060 result = get_user(val, ip); 1061 if (result) 1062 return result; 1063 sfp->cmd_q = val ? 1 : 0; 1064 return 0; 1065 case SG_GET_COMMAND_Q: 1066 return put_user((int) sfp->cmd_q, ip); 1067 case SG_SET_KEEP_ORPHAN: 1068 result = get_user(val, ip); 1069 if (result) 1070 return result; 1071 sfp->keep_orphan = val; 1072 return 0; 1073 case SG_GET_KEEP_ORPHAN: 1074 return put_user((int) sfp->keep_orphan, ip); 1075 case SG_NEXT_CMD_LEN: 1076 result = get_user(val, ip); 1077 if (result) 1078 return result; 1079 if (val > SG_MAX_CDB_SIZE) 1080 return -ENOMEM; 1081 sfp->next_cmd_len = (val > 0) ? val : 0; 1082 return 0; 1083 case SG_GET_VERSION_NUM: 1084 return put_user(sg_version_num, ip); 1085 case SG_GET_ACCESS_COUNT: 1086 /* faked - we don't have a real access count anymore */ 1087 val = (sdp->device ? 1 : 0); 1088 return put_user(val, ip); 1089 case SG_GET_REQUEST_TABLE: 1090 { 1091 sg_req_info_t *rinfo; 1092 1093 rinfo = kcalloc(SG_MAX_QUEUE, SZ_SG_REQ_INFO, 1094 GFP_KERNEL); 1095 if (!rinfo) 1096 return -ENOMEM; 1097 read_lock_irqsave(&sfp->rq_list_lock, iflags); 1098 sg_fill_request_table(sfp, rinfo); 1099 read_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1100 #ifdef CONFIG_COMPAT 1101 if (in_compat_syscall()) 1102 result = put_compat_request_table(p, rinfo); 1103 else 1104 #endif 1105 result = copy_to_user(p, rinfo, 1106 SZ_SG_REQ_INFO * SG_MAX_QUEUE); 1107 result = result ? -EFAULT : 0; 1108 kfree(rinfo); 1109 return result; 1110 } 1111 case SG_EMULATED_HOST: 1112 if (atomic_read(&sdp->detaching)) 1113 return -ENODEV; 1114 return put_user(sdp->device->host->hostt->emulated, ip); 1115 case SCSI_IOCTL_SEND_COMMAND: 1116 if (atomic_read(&sdp->detaching)) 1117 return -ENODEV; 1118 return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p); 1119 case SG_SET_DEBUG: 1120 result = get_user(val, ip); 1121 if (result) 1122 return result; 1123 sdp->sgdebug = (char) val; 1124 return 0; 1125 case BLKSECTGET: 1126 return put_user(max_sectors_bytes(sdp->device->request_queue), 1127 ip); 1128 case BLKTRACESETUP: 1129 return blk_trace_setup(sdp->device->request_queue, 1130 sdp->disk->disk_name, 1131 MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1132 NULL, p); 1133 case BLKTRACESTART: 1134 return blk_trace_startstop(sdp->device->request_queue, 1); 1135 case BLKTRACESTOP: 1136 return blk_trace_startstop(sdp->device->request_queue, 0); 1137 case BLKTRACETEARDOWN: 1138 return blk_trace_remove(sdp->device->request_queue); 1139 case SCSI_IOCTL_GET_IDLUN: 1140 case SCSI_IOCTL_GET_BUS_NUMBER: 1141 case SCSI_IOCTL_PROBE_HOST: 1142 case SG_GET_TRANSFORM: 1143 case SG_SCSI_RESET: 1144 if (atomic_read(&sdp->detaching)) 1145 return -ENODEV; 1146 break; 1147 default: 1148 if (read_only) 1149 return -EPERM; /* don't know so take safe approach */ 1150 break; 1151 } 1152 1153 result = scsi_ioctl_block_when_processing_errors(sdp->device, 1154 cmd_in, filp->f_flags & O_NDELAY); 1155 if (result) 1156 return result; 1157 return scsi_ioctl(sdp->device, cmd_in, p); 1158 } 1159 1160 #ifdef CONFIG_COMPAT 1161 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg) 1162 { 1163 Sg_device *sdp; 1164 Sg_fd *sfp; 1165 struct scsi_device *sdev; 1166 1167 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 1168 return -ENXIO; 1169 1170 sdev = sdp->device; 1171 if (sdev->host->hostt->compat_ioctl) { 1172 int ret; 1173 1174 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg); 1175 1176 return ret; 1177 } 1178 1179 return -ENOIOCTLCMD; 1180 } 1181 #endif 1182 1183 static __poll_t 1184 sg_poll(struct file *filp, poll_table * wait) 1185 { 1186 __poll_t res = 0; 1187 Sg_device *sdp; 1188 Sg_fd *sfp; 1189 Sg_request *srp; 1190 int count = 0; 1191 unsigned long iflags; 1192 1193 sfp = filp->private_data; 1194 if (!sfp) 1195 return EPOLLERR; 1196 sdp = sfp->parentdp; 1197 if (!sdp) 1198 return EPOLLERR; 1199 poll_wait(filp, &sfp->read_wait, wait); 1200 read_lock_irqsave(&sfp->rq_list_lock, iflags); 1201 list_for_each_entry(srp, &sfp->rq_list, entry) { 1202 /* if any read waiting, flag it */ 1203 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned)) 1204 res = EPOLLIN | EPOLLRDNORM; 1205 ++count; 1206 } 1207 read_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1208 1209 if (atomic_read(&sdp->detaching)) 1210 res |= EPOLLHUP; 1211 else if (!sfp->cmd_q) { 1212 if (0 == count) 1213 res |= EPOLLOUT | EPOLLWRNORM; 1214 } else if (count < SG_MAX_QUEUE) 1215 res |= EPOLLOUT | EPOLLWRNORM; 1216 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 1217 "sg_poll: res=0x%x\n", (__force u32) res)); 1218 return res; 1219 } 1220 1221 static int 1222 sg_fasync(int fd, struct file *filp, int mode) 1223 { 1224 Sg_device *sdp; 1225 Sg_fd *sfp; 1226 1227 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 1228 return -ENXIO; 1229 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 1230 "sg_fasync: mode=%d\n", mode)); 1231 1232 return fasync_helper(fd, filp, mode, &sfp->async_qp); 1233 } 1234 1235 static vm_fault_t 1236 sg_vma_fault(struct vm_fault *vmf) 1237 { 1238 struct vm_area_struct *vma = vmf->vma; 1239 Sg_fd *sfp; 1240 unsigned long offset, len, sa; 1241 Sg_scatter_hold *rsv_schp; 1242 int k, length; 1243 1244 if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data))) 1245 return VM_FAULT_SIGBUS; 1246 rsv_schp = &sfp->reserve; 1247 offset = vmf->pgoff << PAGE_SHIFT; 1248 if (offset >= rsv_schp->bufflen) 1249 return VM_FAULT_SIGBUS; 1250 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp, 1251 "sg_vma_fault: offset=%lu, scatg=%d\n", 1252 offset, rsv_schp->k_use_sg)); 1253 sa = vma->vm_start; 1254 length = 1 << (PAGE_SHIFT + rsv_schp->page_order); 1255 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) { 1256 len = vma->vm_end - sa; 1257 len = (len < length) ? len : length; 1258 if (offset < len) { 1259 struct page *page = nth_page(rsv_schp->pages[k], 1260 offset >> PAGE_SHIFT); 1261 get_page(page); /* increment page count */ 1262 vmf->page = page; 1263 return 0; /* success */ 1264 } 1265 sa += len; 1266 offset -= len; 1267 } 1268 1269 return VM_FAULT_SIGBUS; 1270 } 1271 1272 static const struct vm_operations_struct sg_mmap_vm_ops = { 1273 .fault = sg_vma_fault, 1274 }; 1275 1276 static int 1277 sg_mmap(struct file *filp, struct vm_area_struct *vma) 1278 { 1279 Sg_fd *sfp; 1280 unsigned long req_sz, len, sa; 1281 Sg_scatter_hold *rsv_schp; 1282 int k, length; 1283 int ret = 0; 1284 1285 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data))) 1286 return -ENXIO; 1287 req_sz = vma->vm_end - vma->vm_start; 1288 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp, 1289 "sg_mmap starting, vm_start=%p, len=%d\n", 1290 (void *) vma->vm_start, (int) req_sz)); 1291 if (vma->vm_pgoff) 1292 return -EINVAL; /* want no offset */ 1293 rsv_schp = &sfp->reserve; 1294 mutex_lock(&sfp->f_mutex); 1295 if (req_sz > rsv_schp->bufflen) { 1296 ret = -ENOMEM; /* cannot map more than reserved buffer */ 1297 goto out; 1298 } 1299 1300 sa = vma->vm_start; 1301 length = 1 << (PAGE_SHIFT + rsv_schp->page_order); 1302 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) { 1303 len = vma->vm_end - sa; 1304 len = (len < length) ? len : length; 1305 sa += len; 1306 } 1307 1308 sfp->mmap_called = 1; 1309 vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP; 1310 vma->vm_private_data = sfp; 1311 vma->vm_ops = &sg_mmap_vm_ops; 1312 out: 1313 mutex_unlock(&sfp->f_mutex); 1314 return ret; 1315 } 1316 1317 static void 1318 sg_rq_end_io_usercontext(struct work_struct *work) 1319 { 1320 struct sg_request *srp = container_of(work, struct sg_request, ew.work); 1321 struct sg_fd *sfp = srp->parentfp; 1322 1323 sg_finish_rem_req(srp); 1324 sg_remove_request(sfp, srp); 1325 kref_put(&sfp->f_ref, sg_remove_sfp); 1326 } 1327 1328 /* 1329 * This function is a "bottom half" handler that is called by the mid 1330 * level when a command is completed (or has failed). 1331 */ 1332 static void 1333 sg_rq_end_io(struct request *rq, blk_status_t status) 1334 { 1335 struct sg_request *srp = rq->end_io_data; 1336 struct scsi_request *req = scsi_req(rq); 1337 Sg_device *sdp; 1338 Sg_fd *sfp; 1339 unsigned long iflags; 1340 unsigned int ms; 1341 char *sense; 1342 int result, resid, done = 1; 1343 1344 if (WARN_ON(srp->done != 0)) 1345 return; 1346 1347 sfp = srp->parentfp; 1348 if (WARN_ON(sfp == NULL)) 1349 return; 1350 1351 sdp = sfp->parentdp; 1352 if (unlikely(atomic_read(&sdp->detaching))) 1353 pr_info("%s: device detaching\n", __func__); 1354 1355 sense = req->sense; 1356 result = req->result; 1357 resid = req->resid_len; 1358 1359 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp, 1360 "sg_cmd_done: pack_id=%d, res=0x%x\n", 1361 srp->header.pack_id, result)); 1362 srp->header.resid = resid; 1363 ms = jiffies_to_msecs(jiffies); 1364 srp->header.duration = (ms > srp->header.duration) ? 1365 (ms - srp->header.duration) : 0; 1366 if (0 != result) { 1367 struct scsi_sense_hdr sshdr; 1368 1369 srp->header.status = 0xff & result; 1370 srp->header.masked_status = status_byte(result); 1371 srp->header.msg_status = msg_byte(result); 1372 srp->header.host_status = host_byte(result); 1373 srp->header.driver_status = driver_byte(result); 1374 if ((sdp->sgdebug > 0) && 1375 ((CHECK_CONDITION == srp->header.masked_status) || 1376 (COMMAND_TERMINATED == srp->header.masked_status))) 1377 __scsi_print_sense(sdp->device, __func__, sense, 1378 SCSI_SENSE_BUFFERSIZE); 1379 1380 /* Following if statement is a patch supplied by Eric Youngdale */ 1381 if (driver_byte(result) != 0 1382 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr) 1383 && !scsi_sense_is_deferred(&sshdr) 1384 && sshdr.sense_key == UNIT_ATTENTION 1385 && sdp->device->removable) { 1386 /* Detected possible disc change. Set the bit - this */ 1387 /* may be used if there are filesystems using this device */ 1388 sdp->device->changed = 1; 1389 } 1390 } 1391 1392 if (req->sense_len) 1393 memcpy(srp->sense_b, req->sense, SCSI_SENSE_BUFFERSIZE); 1394 1395 /* Rely on write phase to clean out srp status values, so no "else" */ 1396 1397 /* 1398 * Free the request as soon as it is complete so that its resources 1399 * can be reused without waiting for userspace to read() the 1400 * result. But keep the associated bio (if any) around until 1401 * blk_rq_unmap_user() can be called from user context. 1402 */ 1403 srp->rq = NULL; 1404 scsi_req_free_cmd(scsi_req(rq)); 1405 blk_put_request(rq); 1406 1407 write_lock_irqsave(&sfp->rq_list_lock, iflags); 1408 if (unlikely(srp->orphan)) { 1409 if (sfp->keep_orphan) 1410 srp->sg_io_owned = 0; 1411 else 1412 done = 0; 1413 } 1414 srp->done = done; 1415 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1416 1417 if (likely(done)) { 1418 /* Now wake up any sg_read() that is waiting for this 1419 * packet. 1420 */ 1421 wake_up_interruptible(&sfp->read_wait); 1422 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN); 1423 kref_put(&sfp->f_ref, sg_remove_sfp); 1424 } else { 1425 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext); 1426 schedule_work(&srp->ew.work); 1427 } 1428 } 1429 1430 static const struct file_operations sg_fops = { 1431 .owner = THIS_MODULE, 1432 .read = sg_read, 1433 .write = sg_write, 1434 .poll = sg_poll, 1435 .unlocked_ioctl = sg_ioctl, 1436 #ifdef CONFIG_COMPAT 1437 .compat_ioctl = sg_compat_ioctl, 1438 #endif 1439 .open = sg_open, 1440 .mmap = sg_mmap, 1441 .release = sg_release, 1442 .fasync = sg_fasync, 1443 .llseek = no_llseek, 1444 }; 1445 1446 static struct class *sg_sysfs_class; 1447 1448 static int sg_sysfs_valid = 0; 1449 1450 static Sg_device * 1451 sg_alloc(struct gendisk *disk, struct scsi_device *scsidp) 1452 { 1453 struct request_queue *q = scsidp->request_queue; 1454 Sg_device *sdp; 1455 unsigned long iflags; 1456 int error; 1457 u32 k; 1458 1459 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL); 1460 if (!sdp) { 1461 sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device " 1462 "failure\n", __func__); 1463 return ERR_PTR(-ENOMEM); 1464 } 1465 1466 idr_preload(GFP_KERNEL); 1467 write_lock_irqsave(&sg_index_lock, iflags); 1468 1469 error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT); 1470 if (error < 0) { 1471 if (error == -ENOSPC) { 1472 sdev_printk(KERN_WARNING, scsidp, 1473 "Unable to attach sg device type=%d, minor number exceeds %d\n", 1474 scsidp->type, SG_MAX_DEVS - 1); 1475 error = -ENODEV; 1476 } else { 1477 sdev_printk(KERN_WARNING, scsidp, "%s: idr " 1478 "allocation Sg_device failure: %d\n", 1479 __func__, error); 1480 } 1481 goto out_unlock; 1482 } 1483 k = error; 1484 1485 SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp, 1486 "sg_alloc: dev=%d \n", k)); 1487 sprintf(disk->disk_name, "sg%d", k); 1488 disk->first_minor = k; 1489 sdp->disk = disk; 1490 sdp->device = scsidp; 1491 mutex_init(&sdp->open_rel_lock); 1492 INIT_LIST_HEAD(&sdp->sfds); 1493 init_waitqueue_head(&sdp->open_wait); 1494 atomic_set(&sdp->detaching, 0); 1495 rwlock_init(&sdp->sfd_lock); 1496 sdp->sg_tablesize = queue_max_segments(q); 1497 sdp->index = k; 1498 kref_init(&sdp->d_ref); 1499 error = 0; 1500 1501 out_unlock: 1502 write_unlock_irqrestore(&sg_index_lock, iflags); 1503 idr_preload_end(); 1504 1505 if (error) { 1506 kfree(sdp); 1507 return ERR_PTR(error); 1508 } 1509 return sdp; 1510 } 1511 1512 static int 1513 sg_add_device(struct device *cl_dev, struct class_interface *cl_intf) 1514 { 1515 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent); 1516 struct gendisk *disk; 1517 Sg_device *sdp = NULL; 1518 struct cdev * cdev = NULL; 1519 int error; 1520 unsigned long iflags; 1521 1522 disk = alloc_disk(1); 1523 if (!disk) { 1524 pr_warn("%s: alloc_disk failed\n", __func__); 1525 return -ENOMEM; 1526 } 1527 disk->major = SCSI_GENERIC_MAJOR; 1528 1529 error = -ENOMEM; 1530 cdev = cdev_alloc(); 1531 if (!cdev) { 1532 pr_warn("%s: cdev_alloc failed\n", __func__); 1533 goto out; 1534 } 1535 cdev->owner = THIS_MODULE; 1536 cdev->ops = &sg_fops; 1537 1538 sdp = sg_alloc(disk, scsidp); 1539 if (IS_ERR(sdp)) { 1540 pr_warn("%s: sg_alloc failed\n", __func__); 1541 error = PTR_ERR(sdp); 1542 goto out; 1543 } 1544 1545 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1); 1546 if (error) 1547 goto cdev_add_err; 1548 1549 sdp->cdev = cdev; 1550 if (sg_sysfs_valid) { 1551 struct device *sg_class_member; 1552 1553 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent, 1554 MKDEV(SCSI_GENERIC_MAJOR, 1555 sdp->index), 1556 sdp, "%s", disk->disk_name); 1557 if (IS_ERR(sg_class_member)) { 1558 pr_err("%s: device_create failed\n", __func__); 1559 error = PTR_ERR(sg_class_member); 1560 goto cdev_add_err; 1561 } 1562 error = sysfs_create_link(&scsidp->sdev_gendev.kobj, 1563 &sg_class_member->kobj, "generic"); 1564 if (error) 1565 pr_err("%s: unable to make symlink 'generic' back " 1566 "to sg%d\n", __func__, sdp->index); 1567 } else 1568 pr_warn("%s: sg_sys Invalid\n", __func__); 1569 1570 sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d " 1571 "type %d\n", sdp->index, scsidp->type); 1572 1573 dev_set_drvdata(cl_dev, sdp); 1574 1575 return 0; 1576 1577 cdev_add_err: 1578 write_lock_irqsave(&sg_index_lock, iflags); 1579 idr_remove(&sg_index_idr, sdp->index); 1580 write_unlock_irqrestore(&sg_index_lock, iflags); 1581 kfree(sdp); 1582 1583 out: 1584 put_disk(disk); 1585 if (cdev) 1586 cdev_del(cdev); 1587 return error; 1588 } 1589 1590 static void 1591 sg_device_destroy(struct kref *kref) 1592 { 1593 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref); 1594 unsigned long flags; 1595 1596 /* CAUTION! Note that the device can still be found via idr_find() 1597 * even though the refcount is 0. Therefore, do idr_remove() BEFORE 1598 * any other cleanup. 1599 */ 1600 1601 write_lock_irqsave(&sg_index_lock, flags); 1602 idr_remove(&sg_index_idr, sdp->index); 1603 write_unlock_irqrestore(&sg_index_lock, flags); 1604 1605 SCSI_LOG_TIMEOUT(3, 1606 sg_printk(KERN_INFO, sdp, "sg_device_destroy\n")); 1607 1608 put_disk(sdp->disk); 1609 kfree(sdp); 1610 } 1611 1612 static void 1613 sg_remove_device(struct device *cl_dev, struct class_interface *cl_intf) 1614 { 1615 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent); 1616 Sg_device *sdp = dev_get_drvdata(cl_dev); 1617 unsigned long iflags; 1618 Sg_fd *sfp; 1619 int val; 1620 1621 if (!sdp) 1622 return; 1623 /* want sdp->detaching non-zero as soon as possible */ 1624 val = atomic_inc_return(&sdp->detaching); 1625 if (val > 1) 1626 return; /* only want to do following once per device */ 1627 1628 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 1629 "%s\n", __func__)); 1630 1631 read_lock_irqsave(&sdp->sfd_lock, iflags); 1632 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) { 1633 wake_up_interruptible_all(&sfp->read_wait); 1634 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP); 1635 } 1636 wake_up_interruptible_all(&sdp->open_wait); 1637 read_unlock_irqrestore(&sdp->sfd_lock, iflags); 1638 1639 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic"); 1640 device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index)); 1641 cdev_del(sdp->cdev); 1642 sdp->cdev = NULL; 1643 1644 kref_put(&sdp->d_ref, sg_device_destroy); 1645 } 1646 1647 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR); 1648 module_param_named(def_reserved_size, def_reserved_size, int, 1649 S_IRUGO | S_IWUSR); 1650 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR); 1651 1652 MODULE_AUTHOR("Douglas Gilbert"); 1653 MODULE_DESCRIPTION("SCSI generic (sg) driver"); 1654 MODULE_LICENSE("GPL"); 1655 MODULE_VERSION(SG_VERSION_STR); 1656 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR); 1657 1658 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element " 1659 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))"); 1660 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd"); 1661 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))"); 1662 1663 static int __init 1664 init_sg(void) 1665 { 1666 int rc; 1667 1668 if (scatter_elem_sz < PAGE_SIZE) { 1669 scatter_elem_sz = PAGE_SIZE; 1670 scatter_elem_sz_prev = scatter_elem_sz; 1671 } 1672 if (def_reserved_size >= 0) 1673 sg_big_buff = def_reserved_size; 1674 else 1675 def_reserved_size = sg_big_buff; 1676 1677 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), 1678 SG_MAX_DEVS, "sg"); 1679 if (rc) 1680 return rc; 1681 sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic"); 1682 if ( IS_ERR(sg_sysfs_class) ) { 1683 rc = PTR_ERR(sg_sysfs_class); 1684 goto err_out; 1685 } 1686 sg_sysfs_valid = 1; 1687 rc = scsi_register_interface(&sg_interface); 1688 if (0 == rc) { 1689 #ifdef CONFIG_SCSI_PROC_FS 1690 sg_proc_init(); 1691 #endif /* CONFIG_SCSI_PROC_FS */ 1692 return 0; 1693 } 1694 class_destroy(sg_sysfs_class); 1695 err_out: 1696 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS); 1697 return rc; 1698 } 1699 1700 static void __exit 1701 exit_sg(void) 1702 { 1703 #ifdef CONFIG_SCSI_PROC_FS 1704 remove_proc_subtree("scsi/sg", NULL); 1705 #endif /* CONFIG_SCSI_PROC_FS */ 1706 scsi_unregister_interface(&sg_interface); 1707 class_destroy(sg_sysfs_class); 1708 sg_sysfs_valid = 0; 1709 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), 1710 SG_MAX_DEVS); 1711 idr_destroy(&sg_index_idr); 1712 } 1713 1714 static int 1715 sg_start_req(Sg_request *srp, unsigned char *cmd) 1716 { 1717 int res; 1718 struct request *rq; 1719 struct scsi_request *req; 1720 Sg_fd *sfp = srp->parentfp; 1721 sg_io_hdr_t *hp = &srp->header; 1722 int dxfer_len = (int) hp->dxfer_len; 1723 int dxfer_dir = hp->dxfer_direction; 1724 unsigned int iov_count = hp->iovec_count; 1725 Sg_scatter_hold *req_schp = &srp->data; 1726 Sg_scatter_hold *rsv_schp = &sfp->reserve; 1727 struct request_queue *q = sfp->parentdp->device->request_queue; 1728 struct rq_map_data *md, map_data; 1729 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ; 1730 unsigned char *long_cmdp = NULL; 1731 1732 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 1733 "sg_start_req: dxfer_len=%d\n", 1734 dxfer_len)); 1735 1736 if (hp->cmd_len > BLK_MAX_CDB) { 1737 long_cmdp = kzalloc(hp->cmd_len, GFP_KERNEL); 1738 if (!long_cmdp) 1739 return -ENOMEM; 1740 } 1741 1742 /* 1743 * NOTE 1744 * 1745 * With scsi-mq enabled, there are a fixed number of preallocated 1746 * requests equal in number to shost->can_queue. If all of the 1747 * preallocated requests are already in use, then blk_get_request() 1748 * will sleep until an active command completes, freeing up a request. 1749 * Although waiting in an asynchronous interface is less than ideal, we 1750 * do not want to use BLK_MQ_REQ_NOWAIT here because userspace might 1751 * not expect an EWOULDBLOCK from this condition. 1752 */ 1753 rq = blk_get_request(q, hp->dxfer_direction == SG_DXFER_TO_DEV ? 1754 REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, 0); 1755 if (IS_ERR(rq)) { 1756 kfree(long_cmdp); 1757 return PTR_ERR(rq); 1758 } 1759 req = scsi_req(rq); 1760 1761 if (hp->cmd_len > BLK_MAX_CDB) 1762 req->cmd = long_cmdp; 1763 memcpy(req->cmd, cmd, hp->cmd_len); 1764 req->cmd_len = hp->cmd_len; 1765 1766 srp->rq = rq; 1767 rq->end_io_data = srp; 1768 req->retries = SG_DEFAULT_RETRIES; 1769 1770 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE)) 1771 return 0; 1772 1773 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO && 1774 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count && 1775 !sfp->parentdp->device->host->unchecked_isa_dma && 1776 blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len)) 1777 md = NULL; 1778 else 1779 md = &map_data; 1780 1781 if (md) { 1782 mutex_lock(&sfp->f_mutex); 1783 if (dxfer_len <= rsv_schp->bufflen && 1784 !sfp->res_in_use) { 1785 sfp->res_in_use = 1; 1786 sg_link_reserve(sfp, srp, dxfer_len); 1787 } else if (hp->flags & SG_FLAG_MMAP_IO) { 1788 res = -EBUSY; /* sfp->res_in_use == 1 */ 1789 if (dxfer_len > rsv_schp->bufflen) 1790 res = -ENOMEM; 1791 mutex_unlock(&sfp->f_mutex); 1792 return res; 1793 } else { 1794 res = sg_build_indirect(req_schp, sfp, dxfer_len); 1795 if (res) { 1796 mutex_unlock(&sfp->f_mutex); 1797 return res; 1798 } 1799 } 1800 mutex_unlock(&sfp->f_mutex); 1801 1802 md->pages = req_schp->pages; 1803 md->page_order = req_schp->page_order; 1804 md->nr_entries = req_schp->k_use_sg; 1805 md->offset = 0; 1806 md->null_mapped = hp->dxferp ? 0 : 1; 1807 if (dxfer_dir == SG_DXFER_TO_FROM_DEV) 1808 md->from_user = 1; 1809 else 1810 md->from_user = 0; 1811 } 1812 1813 if (iov_count) { 1814 struct iovec *iov = NULL; 1815 struct iov_iter i; 1816 1817 #ifdef CONFIG_COMPAT 1818 if (in_compat_syscall()) 1819 res = compat_import_iovec(rw, hp->dxferp, iov_count, 1820 0, &iov, &i); 1821 else 1822 #endif 1823 res = import_iovec(rw, hp->dxferp, iov_count, 1824 0, &iov, &i); 1825 if (res < 0) 1826 return res; 1827 1828 iov_iter_truncate(&i, hp->dxfer_len); 1829 if (!iov_iter_count(&i)) { 1830 kfree(iov); 1831 return -EINVAL; 1832 } 1833 1834 res = blk_rq_map_user_iov(q, rq, md, &i, GFP_ATOMIC); 1835 kfree(iov); 1836 } else 1837 res = blk_rq_map_user(q, rq, md, hp->dxferp, 1838 hp->dxfer_len, GFP_ATOMIC); 1839 1840 if (!res) { 1841 srp->bio = rq->bio; 1842 1843 if (!md) { 1844 req_schp->dio_in_use = 1; 1845 hp->info |= SG_INFO_DIRECT_IO; 1846 } 1847 } 1848 return res; 1849 } 1850 1851 static int 1852 sg_finish_rem_req(Sg_request *srp) 1853 { 1854 int ret = 0; 1855 1856 Sg_fd *sfp = srp->parentfp; 1857 Sg_scatter_hold *req_schp = &srp->data; 1858 1859 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 1860 "sg_finish_rem_req: res_used=%d\n", 1861 (int) srp->res_used)); 1862 if (srp->bio) 1863 ret = blk_rq_unmap_user(srp->bio); 1864 1865 if (srp->rq) { 1866 scsi_req_free_cmd(scsi_req(srp->rq)); 1867 blk_put_request(srp->rq); 1868 } 1869 1870 if (srp->res_used) 1871 sg_unlink_reserve(sfp, srp); 1872 else 1873 sg_remove_scat(sfp, req_schp); 1874 1875 return ret; 1876 } 1877 1878 static int 1879 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize) 1880 { 1881 int sg_bufflen = tablesize * sizeof(struct page *); 1882 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN; 1883 1884 schp->pages = kzalloc(sg_bufflen, gfp_flags); 1885 if (!schp->pages) 1886 return -ENOMEM; 1887 schp->sglist_len = sg_bufflen; 1888 return tablesize; /* number of scat_gath elements allocated */ 1889 } 1890 1891 static int 1892 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size) 1893 { 1894 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems; 1895 int sg_tablesize = sfp->parentdp->sg_tablesize; 1896 int blk_size = buff_size, order; 1897 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN | __GFP_ZERO; 1898 struct sg_device *sdp = sfp->parentdp; 1899 1900 if (blk_size < 0) 1901 return -EFAULT; 1902 if (0 == blk_size) 1903 ++blk_size; /* don't know why */ 1904 /* round request up to next highest SG_SECTOR_SZ byte boundary */ 1905 blk_size = ALIGN(blk_size, SG_SECTOR_SZ); 1906 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 1907 "sg_build_indirect: buff_size=%d, blk_size=%d\n", 1908 buff_size, blk_size)); 1909 1910 /* N.B. ret_sz carried into this block ... */ 1911 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize); 1912 if (mx_sc_elems < 0) 1913 return mx_sc_elems; /* most likely -ENOMEM */ 1914 1915 num = scatter_elem_sz; 1916 if (unlikely(num != scatter_elem_sz_prev)) { 1917 if (num < PAGE_SIZE) { 1918 scatter_elem_sz = PAGE_SIZE; 1919 scatter_elem_sz_prev = PAGE_SIZE; 1920 } else 1921 scatter_elem_sz_prev = num; 1922 } 1923 1924 if (sdp->device->host->unchecked_isa_dma) 1925 gfp_mask |= GFP_DMA; 1926 1927 order = get_order(num); 1928 retry: 1929 ret_sz = 1 << (PAGE_SHIFT + order); 1930 1931 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems; 1932 k++, rem_sz -= ret_sz) { 1933 1934 num = (rem_sz > scatter_elem_sz_prev) ? 1935 scatter_elem_sz_prev : rem_sz; 1936 1937 schp->pages[k] = alloc_pages(gfp_mask, order); 1938 if (!schp->pages[k]) 1939 goto out; 1940 1941 if (num == scatter_elem_sz_prev) { 1942 if (unlikely(ret_sz > scatter_elem_sz_prev)) { 1943 scatter_elem_sz = ret_sz; 1944 scatter_elem_sz_prev = ret_sz; 1945 } 1946 } 1947 1948 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp, 1949 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n", 1950 k, num, ret_sz)); 1951 } /* end of for loop */ 1952 1953 schp->page_order = order; 1954 schp->k_use_sg = k; 1955 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp, 1956 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n", 1957 k, rem_sz)); 1958 1959 schp->bufflen = blk_size; 1960 if (rem_sz > 0) /* must have failed */ 1961 return -ENOMEM; 1962 return 0; 1963 out: 1964 for (i = 0; i < k; i++) 1965 __free_pages(schp->pages[i], order); 1966 1967 if (--order >= 0) 1968 goto retry; 1969 1970 return -ENOMEM; 1971 } 1972 1973 static void 1974 sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp) 1975 { 1976 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 1977 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg)); 1978 if (schp->pages && schp->sglist_len > 0) { 1979 if (!schp->dio_in_use) { 1980 int k; 1981 1982 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) { 1983 SCSI_LOG_TIMEOUT(5, 1984 sg_printk(KERN_INFO, sfp->parentdp, 1985 "sg_remove_scat: k=%d, pg=0x%p\n", 1986 k, schp->pages[k])); 1987 __free_pages(schp->pages[k], schp->page_order); 1988 } 1989 1990 kfree(schp->pages); 1991 } 1992 } 1993 memset(schp, 0, sizeof (*schp)); 1994 } 1995 1996 static int 1997 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer) 1998 { 1999 Sg_scatter_hold *schp = &srp->data; 2000 int k, num; 2001 2002 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp, 2003 "sg_read_oxfer: num_read_xfer=%d\n", 2004 num_read_xfer)); 2005 if ((!outp) || (num_read_xfer <= 0)) 2006 return 0; 2007 2008 num = 1 << (PAGE_SHIFT + schp->page_order); 2009 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) { 2010 if (num > num_read_xfer) { 2011 if (copy_to_user(outp, page_address(schp->pages[k]), 2012 num_read_xfer)) 2013 return -EFAULT; 2014 break; 2015 } else { 2016 if (copy_to_user(outp, page_address(schp->pages[k]), 2017 num)) 2018 return -EFAULT; 2019 num_read_xfer -= num; 2020 if (num_read_xfer <= 0) 2021 break; 2022 outp += num; 2023 } 2024 } 2025 2026 return 0; 2027 } 2028 2029 static void 2030 sg_build_reserve(Sg_fd * sfp, int req_size) 2031 { 2032 Sg_scatter_hold *schp = &sfp->reserve; 2033 2034 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 2035 "sg_build_reserve: req_size=%d\n", req_size)); 2036 do { 2037 if (req_size < PAGE_SIZE) 2038 req_size = PAGE_SIZE; 2039 if (0 == sg_build_indirect(schp, sfp, req_size)) 2040 return; 2041 else 2042 sg_remove_scat(sfp, schp); 2043 req_size >>= 1; /* divide by 2 */ 2044 } while (req_size > (PAGE_SIZE / 2)); 2045 } 2046 2047 static void 2048 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size) 2049 { 2050 Sg_scatter_hold *req_schp = &srp->data; 2051 Sg_scatter_hold *rsv_schp = &sfp->reserve; 2052 int k, num, rem; 2053 2054 srp->res_used = 1; 2055 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 2056 "sg_link_reserve: size=%d\n", size)); 2057 rem = size; 2058 2059 num = 1 << (PAGE_SHIFT + rsv_schp->page_order); 2060 for (k = 0; k < rsv_schp->k_use_sg; k++) { 2061 if (rem <= num) { 2062 req_schp->k_use_sg = k + 1; 2063 req_schp->sglist_len = rsv_schp->sglist_len; 2064 req_schp->pages = rsv_schp->pages; 2065 2066 req_schp->bufflen = size; 2067 req_schp->page_order = rsv_schp->page_order; 2068 break; 2069 } else 2070 rem -= num; 2071 } 2072 2073 if (k >= rsv_schp->k_use_sg) 2074 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp, 2075 "sg_link_reserve: BAD size\n")); 2076 } 2077 2078 static void 2079 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp) 2080 { 2081 Sg_scatter_hold *req_schp = &srp->data; 2082 2083 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp, 2084 "sg_unlink_reserve: req->k_use_sg=%d\n", 2085 (int) req_schp->k_use_sg)); 2086 req_schp->k_use_sg = 0; 2087 req_schp->bufflen = 0; 2088 req_schp->pages = NULL; 2089 req_schp->page_order = 0; 2090 req_schp->sglist_len = 0; 2091 srp->res_used = 0; 2092 /* Called without mutex lock to avoid deadlock */ 2093 sfp->res_in_use = 0; 2094 } 2095 2096 static Sg_request * 2097 sg_get_rq_mark(Sg_fd * sfp, int pack_id) 2098 { 2099 Sg_request *resp; 2100 unsigned long iflags; 2101 2102 write_lock_irqsave(&sfp->rq_list_lock, iflags); 2103 list_for_each_entry(resp, &sfp->rq_list, entry) { 2104 /* look for requests that are ready + not SG_IO owned */ 2105 if ((1 == resp->done) && (!resp->sg_io_owned) && 2106 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) { 2107 resp->done = 2; /* guard against other readers */ 2108 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2109 return resp; 2110 } 2111 } 2112 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2113 return NULL; 2114 } 2115 2116 /* always adds to end of list */ 2117 static Sg_request * 2118 sg_add_request(Sg_fd * sfp) 2119 { 2120 int k; 2121 unsigned long iflags; 2122 Sg_request *rp = sfp->req_arr; 2123 2124 write_lock_irqsave(&sfp->rq_list_lock, iflags); 2125 if (!list_empty(&sfp->rq_list)) { 2126 if (!sfp->cmd_q) 2127 goto out_unlock; 2128 2129 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) { 2130 if (!rp->parentfp) 2131 break; 2132 } 2133 if (k >= SG_MAX_QUEUE) 2134 goto out_unlock; 2135 } 2136 memset(rp, 0, sizeof (Sg_request)); 2137 rp->parentfp = sfp; 2138 rp->header.duration = jiffies_to_msecs(jiffies); 2139 list_add_tail(&rp->entry, &sfp->rq_list); 2140 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2141 return rp; 2142 out_unlock: 2143 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2144 return NULL; 2145 } 2146 2147 /* Return of 1 for found; 0 for not found */ 2148 static int 2149 sg_remove_request(Sg_fd * sfp, Sg_request * srp) 2150 { 2151 unsigned long iflags; 2152 int res = 0; 2153 2154 if (!sfp || !srp || list_empty(&sfp->rq_list)) 2155 return res; 2156 write_lock_irqsave(&sfp->rq_list_lock, iflags); 2157 if (!list_empty(&srp->entry)) { 2158 list_del(&srp->entry); 2159 srp->parentfp = NULL; 2160 res = 1; 2161 } 2162 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2163 return res; 2164 } 2165 2166 static Sg_fd * 2167 sg_add_sfp(Sg_device * sdp) 2168 { 2169 Sg_fd *sfp; 2170 unsigned long iflags; 2171 int bufflen; 2172 2173 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN); 2174 if (!sfp) 2175 return ERR_PTR(-ENOMEM); 2176 2177 init_waitqueue_head(&sfp->read_wait); 2178 rwlock_init(&sfp->rq_list_lock); 2179 INIT_LIST_HEAD(&sfp->rq_list); 2180 kref_init(&sfp->f_ref); 2181 mutex_init(&sfp->f_mutex); 2182 sfp->timeout = SG_DEFAULT_TIMEOUT; 2183 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER; 2184 sfp->force_packid = SG_DEF_FORCE_PACK_ID; 2185 sfp->cmd_q = SG_DEF_COMMAND_Q; 2186 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN; 2187 sfp->parentdp = sdp; 2188 write_lock_irqsave(&sdp->sfd_lock, iflags); 2189 if (atomic_read(&sdp->detaching)) { 2190 write_unlock_irqrestore(&sdp->sfd_lock, iflags); 2191 kfree(sfp); 2192 return ERR_PTR(-ENODEV); 2193 } 2194 list_add_tail(&sfp->sfd_siblings, &sdp->sfds); 2195 write_unlock_irqrestore(&sdp->sfd_lock, iflags); 2196 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 2197 "sg_add_sfp: sfp=0x%p\n", sfp)); 2198 if (unlikely(sg_big_buff != def_reserved_size)) 2199 sg_big_buff = def_reserved_size; 2200 2201 bufflen = min_t(int, sg_big_buff, 2202 max_sectors_bytes(sdp->device->request_queue)); 2203 sg_build_reserve(sfp, bufflen); 2204 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 2205 "sg_add_sfp: bufflen=%d, k_use_sg=%d\n", 2206 sfp->reserve.bufflen, 2207 sfp->reserve.k_use_sg)); 2208 2209 kref_get(&sdp->d_ref); 2210 __module_get(THIS_MODULE); 2211 return sfp; 2212 } 2213 2214 static void 2215 sg_remove_sfp_usercontext(struct work_struct *work) 2216 { 2217 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work); 2218 struct sg_device *sdp = sfp->parentdp; 2219 Sg_request *srp; 2220 unsigned long iflags; 2221 2222 /* Cleanup any responses which were never read(). */ 2223 write_lock_irqsave(&sfp->rq_list_lock, iflags); 2224 while (!list_empty(&sfp->rq_list)) { 2225 srp = list_first_entry(&sfp->rq_list, Sg_request, entry); 2226 sg_finish_rem_req(srp); 2227 list_del(&srp->entry); 2228 srp->parentfp = NULL; 2229 } 2230 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2231 2232 if (sfp->reserve.bufflen > 0) { 2233 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp, 2234 "sg_remove_sfp: bufflen=%d, k_use_sg=%d\n", 2235 (int) sfp->reserve.bufflen, 2236 (int) sfp->reserve.k_use_sg)); 2237 sg_remove_scat(sfp, &sfp->reserve); 2238 } 2239 2240 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp, 2241 "sg_remove_sfp: sfp=0x%p\n", sfp)); 2242 kfree(sfp); 2243 2244 scsi_device_put(sdp->device); 2245 kref_put(&sdp->d_ref, sg_device_destroy); 2246 module_put(THIS_MODULE); 2247 } 2248 2249 static void 2250 sg_remove_sfp(struct kref *kref) 2251 { 2252 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref); 2253 struct sg_device *sdp = sfp->parentdp; 2254 unsigned long iflags; 2255 2256 write_lock_irqsave(&sdp->sfd_lock, iflags); 2257 list_del(&sfp->sfd_siblings); 2258 write_unlock_irqrestore(&sdp->sfd_lock, iflags); 2259 2260 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext); 2261 schedule_work(&sfp->ew.work); 2262 } 2263 2264 #ifdef CONFIG_SCSI_PROC_FS 2265 static int 2266 sg_idr_max_id(int id, void *p, void *data) 2267 { 2268 int *k = data; 2269 2270 if (*k < id) 2271 *k = id; 2272 2273 return 0; 2274 } 2275 2276 static int 2277 sg_last_dev(void) 2278 { 2279 int k = -1; 2280 unsigned long iflags; 2281 2282 read_lock_irqsave(&sg_index_lock, iflags); 2283 idr_for_each(&sg_index_idr, sg_idr_max_id, &k); 2284 read_unlock_irqrestore(&sg_index_lock, iflags); 2285 return k + 1; /* origin 1 */ 2286 } 2287 #endif 2288 2289 /* must be called with sg_index_lock held */ 2290 static Sg_device *sg_lookup_dev(int dev) 2291 { 2292 return idr_find(&sg_index_idr, dev); 2293 } 2294 2295 static Sg_device * 2296 sg_get_dev(int dev) 2297 { 2298 struct sg_device *sdp; 2299 unsigned long flags; 2300 2301 read_lock_irqsave(&sg_index_lock, flags); 2302 sdp = sg_lookup_dev(dev); 2303 if (!sdp) 2304 sdp = ERR_PTR(-ENXIO); 2305 else if (atomic_read(&sdp->detaching)) { 2306 /* If sdp->detaching, then the refcount may already be 0, in 2307 * which case it would be a bug to do kref_get(). 2308 */ 2309 sdp = ERR_PTR(-ENODEV); 2310 } else 2311 kref_get(&sdp->d_ref); 2312 read_unlock_irqrestore(&sg_index_lock, flags); 2313 2314 return sdp; 2315 } 2316 2317 #ifdef CONFIG_SCSI_PROC_FS 2318 static int sg_proc_seq_show_int(struct seq_file *s, void *v); 2319 2320 static int sg_proc_single_open_adio(struct inode *inode, struct file *file); 2321 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer, 2322 size_t count, loff_t *off); 2323 static const struct file_operations adio_fops = { 2324 .owner = THIS_MODULE, 2325 .open = sg_proc_single_open_adio, 2326 .read = seq_read, 2327 .llseek = seq_lseek, 2328 .write = sg_proc_write_adio, 2329 .release = single_release, 2330 }; 2331 2332 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file); 2333 static ssize_t sg_proc_write_dressz(struct file *filp, 2334 const char __user *buffer, size_t count, loff_t *off); 2335 static const struct file_operations dressz_fops = { 2336 .owner = THIS_MODULE, 2337 .open = sg_proc_single_open_dressz, 2338 .read = seq_read, 2339 .llseek = seq_lseek, 2340 .write = sg_proc_write_dressz, 2341 .release = single_release, 2342 }; 2343 2344 static int sg_proc_seq_show_version(struct seq_file *s, void *v); 2345 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v); 2346 static int sg_proc_seq_show_dev(struct seq_file *s, void *v); 2347 static void * dev_seq_start(struct seq_file *s, loff_t *pos); 2348 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos); 2349 static void dev_seq_stop(struct seq_file *s, void *v); 2350 static const struct seq_operations dev_seq_ops = { 2351 .start = dev_seq_start, 2352 .next = dev_seq_next, 2353 .stop = dev_seq_stop, 2354 .show = sg_proc_seq_show_dev, 2355 }; 2356 2357 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v); 2358 static const struct seq_operations devstrs_seq_ops = { 2359 .start = dev_seq_start, 2360 .next = dev_seq_next, 2361 .stop = dev_seq_stop, 2362 .show = sg_proc_seq_show_devstrs, 2363 }; 2364 2365 static int sg_proc_seq_show_debug(struct seq_file *s, void *v); 2366 static const struct seq_operations debug_seq_ops = { 2367 .start = dev_seq_start, 2368 .next = dev_seq_next, 2369 .stop = dev_seq_stop, 2370 .show = sg_proc_seq_show_debug, 2371 }; 2372 2373 static int 2374 sg_proc_init(void) 2375 { 2376 struct proc_dir_entry *p; 2377 2378 p = proc_mkdir("scsi/sg", NULL); 2379 if (!p) 2380 return 1; 2381 2382 proc_create("allow_dio", S_IRUGO | S_IWUSR, p, &adio_fops); 2383 proc_create_seq("debug", S_IRUGO, p, &debug_seq_ops); 2384 proc_create("def_reserved_size", S_IRUGO | S_IWUSR, p, &dressz_fops); 2385 proc_create_single("device_hdr", S_IRUGO, p, sg_proc_seq_show_devhdr); 2386 proc_create_seq("devices", S_IRUGO, p, &dev_seq_ops); 2387 proc_create_seq("device_strs", S_IRUGO, p, &devstrs_seq_ops); 2388 proc_create_single("version", S_IRUGO, p, sg_proc_seq_show_version); 2389 return 0; 2390 } 2391 2392 2393 static int sg_proc_seq_show_int(struct seq_file *s, void *v) 2394 { 2395 seq_printf(s, "%d\n", *((int *)s->private)); 2396 return 0; 2397 } 2398 2399 static int sg_proc_single_open_adio(struct inode *inode, struct file *file) 2400 { 2401 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio); 2402 } 2403 2404 static ssize_t 2405 sg_proc_write_adio(struct file *filp, const char __user *buffer, 2406 size_t count, loff_t *off) 2407 { 2408 int err; 2409 unsigned long num; 2410 2411 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) 2412 return -EACCES; 2413 err = kstrtoul_from_user(buffer, count, 0, &num); 2414 if (err) 2415 return err; 2416 sg_allow_dio = num ? 1 : 0; 2417 return count; 2418 } 2419 2420 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file) 2421 { 2422 return single_open(file, sg_proc_seq_show_int, &sg_big_buff); 2423 } 2424 2425 static ssize_t 2426 sg_proc_write_dressz(struct file *filp, const char __user *buffer, 2427 size_t count, loff_t *off) 2428 { 2429 int err; 2430 unsigned long k = ULONG_MAX; 2431 2432 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) 2433 return -EACCES; 2434 2435 err = kstrtoul_from_user(buffer, count, 0, &k); 2436 if (err) 2437 return err; 2438 if (k <= 1048576) { /* limit "big buff" to 1 MB */ 2439 sg_big_buff = k; 2440 return count; 2441 } 2442 return -ERANGE; 2443 } 2444 2445 static int sg_proc_seq_show_version(struct seq_file *s, void *v) 2446 { 2447 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR, 2448 sg_version_date); 2449 return 0; 2450 } 2451 2452 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v) 2453 { 2454 seq_puts(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n"); 2455 return 0; 2456 } 2457 2458 struct sg_proc_deviter { 2459 loff_t index; 2460 size_t max; 2461 }; 2462 2463 static void * dev_seq_start(struct seq_file *s, loff_t *pos) 2464 { 2465 struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL); 2466 2467 s->private = it; 2468 if (! it) 2469 return NULL; 2470 2471 it->index = *pos; 2472 it->max = sg_last_dev(); 2473 if (it->index >= it->max) 2474 return NULL; 2475 return it; 2476 } 2477 2478 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos) 2479 { 2480 struct sg_proc_deviter * it = s->private; 2481 2482 *pos = ++it->index; 2483 return (it->index < it->max) ? it : NULL; 2484 } 2485 2486 static void dev_seq_stop(struct seq_file *s, void *v) 2487 { 2488 kfree(s->private); 2489 } 2490 2491 static int sg_proc_seq_show_dev(struct seq_file *s, void *v) 2492 { 2493 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v; 2494 Sg_device *sdp; 2495 struct scsi_device *scsidp; 2496 unsigned long iflags; 2497 2498 read_lock_irqsave(&sg_index_lock, iflags); 2499 sdp = it ? sg_lookup_dev(it->index) : NULL; 2500 if ((NULL == sdp) || (NULL == sdp->device) || 2501 (atomic_read(&sdp->detaching))) 2502 seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n"); 2503 else { 2504 scsidp = sdp->device; 2505 seq_printf(s, "%d\t%d\t%d\t%llu\t%d\t%d\t%d\t%d\t%d\n", 2506 scsidp->host->host_no, scsidp->channel, 2507 scsidp->id, scsidp->lun, (int) scsidp->type, 2508 1, 2509 (int) scsidp->queue_depth, 2510 (int) atomic_read(&scsidp->device_busy), 2511 (int) scsi_device_online(scsidp)); 2512 } 2513 read_unlock_irqrestore(&sg_index_lock, iflags); 2514 return 0; 2515 } 2516 2517 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v) 2518 { 2519 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v; 2520 Sg_device *sdp; 2521 struct scsi_device *scsidp; 2522 unsigned long iflags; 2523 2524 read_lock_irqsave(&sg_index_lock, iflags); 2525 sdp = it ? sg_lookup_dev(it->index) : NULL; 2526 scsidp = sdp ? sdp->device : NULL; 2527 if (sdp && scsidp && (!atomic_read(&sdp->detaching))) 2528 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n", 2529 scsidp->vendor, scsidp->model, scsidp->rev); 2530 else 2531 seq_puts(s, "<no active device>\n"); 2532 read_unlock_irqrestore(&sg_index_lock, iflags); 2533 return 0; 2534 } 2535 2536 /* must be called while holding sg_index_lock */ 2537 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp) 2538 { 2539 int k, new_interface, blen, usg; 2540 Sg_request *srp; 2541 Sg_fd *fp; 2542 const sg_io_hdr_t *hp; 2543 const char * cp; 2544 unsigned int ms; 2545 2546 k = 0; 2547 list_for_each_entry(fp, &sdp->sfds, sfd_siblings) { 2548 k++; 2549 read_lock(&fp->rq_list_lock); /* irqs already disabled */ 2550 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d " 2551 "(res)sgat=%d low_dma=%d\n", k, 2552 jiffies_to_msecs(fp->timeout), 2553 fp->reserve.bufflen, 2554 (int) fp->reserve.k_use_sg, 2555 (int) sdp->device->host->unchecked_isa_dma); 2556 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n", 2557 (int) fp->cmd_q, (int) fp->force_packid, 2558 (int) fp->keep_orphan); 2559 list_for_each_entry(srp, &fp->rq_list, entry) { 2560 hp = &srp->header; 2561 new_interface = (hp->interface_id == '\0') ? 0 : 1; 2562 if (srp->res_used) { 2563 if (new_interface && 2564 (SG_FLAG_MMAP_IO & hp->flags)) 2565 cp = " mmap>> "; 2566 else 2567 cp = " rb>> "; 2568 } else { 2569 if (SG_INFO_DIRECT_IO_MASK & hp->info) 2570 cp = " dio>> "; 2571 else 2572 cp = " "; 2573 } 2574 seq_puts(s, cp); 2575 blen = srp->data.bufflen; 2576 usg = srp->data.k_use_sg; 2577 seq_puts(s, srp->done ? 2578 ((1 == srp->done) ? "rcv:" : "fin:") 2579 : "act:"); 2580 seq_printf(s, " id=%d blen=%d", 2581 srp->header.pack_id, blen); 2582 if (srp->done) 2583 seq_printf(s, " dur=%d", hp->duration); 2584 else { 2585 ms = jiffies_to_msecs(jiffies); 2586 seq_printf(s, " t_o/elap=%d/%d", 2587 (new_interface ? hp->timeout : 2588 jiffies_to_msecs(fp->timeout)), 2589 (ms > hp->duration ? ms - hp->duration : 0)); 2590 } 2591 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg, 2592 (int) srp->data.cmd_opcode); 2593 } 2594 if (list_empty(&fp->rq_list)) 2595 seq_puts(s, " No requests active\n"); 2596 read_unlock(&fp->rq_list_lock); 2597 } 2598 } 2599 2600 static int sg_proc_seq_show_debug(struct seq_file *s, void *v) 2601 { 2602 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v; 2603 Sg_device *sdp; 2604 unsigned long iflags; 2605 2606 if (it && (0 == it->index)) 2607 seq_printf(s, "max_active_device=%d def_reserved_size=%d\n", 2608 (int)it->max, sg_big_buff); 2609 2610 read_lock_irqsave(&sg_index_lock, iflags); 2611 sdp = it ? sg_lookup_dev(it->index) : NULL; 2612 if (NULL == sdp) 2613 goto skip; 2614 read_lock(&sdp->sfd_lock); 2615 if (!list_empty(&sdp->sfds)) { 2616 seq_printf(s, " >>> device=%s ", sdp->disk->disk_name); 2617 if (atomic_read(&sdp->detaching)) 2618 seq_puts(s, "detaching pending close "); 2619 else if (sdp->device) { 2620 struct scsi_device *scsidp = sdp->device; 2621 2622 seq_printf(s, "%d:%d:%d:%llu em=%d", 2623 scsidp->host->host_no, 2624 scsidp->channel, scsidp->id, 2625 scsidp->lun, 2626 scsidp->host->hostt->emulated); 2627 } 2628 seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n", 2629 sdp->sg_tablesize, sdp->exclude, sdp->open_cnt); 2630 sg_proc_debug_helper(s, sdp); 2631 } 2632 read_unlock(&sdp->sfd_lock); 2633 skip: 2634 read_unlock_irqrestore(&sg_index_lock, iflags); 2635 return 0; 2636 } 2637 2638 #endif /* CONFIG_SCSI_PROC_FS */ 2639 2640 module_init(init_sg); 2641 module_exit(exit_sg); 2642