1 /* 2 * History: 3 * Started: Aug 9 by Lawrence Foard (entropy@world.std.com), 4 * to allow user process control of SCSI devices. 5 * Development Sponsored by Killy Corp. NY NY 6 * 7 * Original driver (sg.c): 8 * Copyright (C) 1992 Lawrence Foard 9 * Version 2 and 3 extensions to driver: 10 * Copyright (C) 1998 - 2014 Douglas Gilbert 11 * 12 * This program is free software; you can redistribute it and/or modify 13 * it under the terms of the GNU General Public License as published by 14 * the Free Software Foundation; either version 2, or (at your option) 15 * any later version. 16 * 17 */ 18 19 static int sg_version_num = 30536; /* 2 digits for each component */ 20 #define SG_VERSION_STR "3.5.36" 21 22 /* 23 * D. P. Gilbert (dgilbert@interlog.com), notes: 24 * - scsi logging is available via SCSI_LOG_TIMEOUT macros. First 25 * the kernel/module needs to be built with CONFIG_SCSI_LOGGING 26 * (otherwise the macros compile to empty statements). 27 * 28 */ 29 #include <linux/module.h> 30 31 #include <linux/fs.h> 32 #include <linux/kernel.h> 33 #include <linux/sched.h> 34 #include <linux/string.h> 35 #include <linux/mm.h> 36 #include <linux/errno.h> 37 #include <linux/mtio.h> 38 #include <linux/ioctl.h> 39 #include <linux/slab.h> 40 #include <linux/fcntl.h> 41 #include <linux/init.h> 42 #include <linux/poll.h> 43 #include <linux/moduleparam.h> 44 #include <linux/cdev.h> 45 #include <linux/idr.h> 46 #include <linux/seq_file.h> 47 #include <linux/blkdev.h> 48 #include <linux/delay.h> 49 #include <linux/blktrace_api.h> 50 #include <linux/mutex.h> 51 #include <linux/atomic.h> 52 #include <linux/ratelimit.h> 53 #include <linux/uio.h> 54 #include <linux/cred.h> /* for sg_check_file_access() */ 55 56 #include "scsi.h" 57 #include <scsi/scsi_dbg.h> 58 #include <scsi/scsi_host.h> 59 #include <scsi/scsi_driver.h> 60 #include <scsi/scsi_ioctl.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 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 struct gendisk *disk; 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, \ 211 (sdp)->disk->disk_name, fmt, ##a) 212 213 /* 214 * The SCSI interfaces that use read() and write() as an asynchronous variant of 215 * ioctl(..., SG_IO, ...) are fundamentally unsafe, since there are lots of ways 216 * to trigger read() and write() calls from various contexts with elevated 217 * privileges. This can lead to kernel memory corruption (e.g. if these 218 * interfaces are called through splice()) and privilege escalation inside 219 * userspace (e.g. if a process with access to such a device passes a file 220 * descriptor to a SUID binary as stdin/stdout/stderr). 221 * 222 * This function provides protection for the legacy API by restricting the 223 * calling context. 224 */ 225 static int sg_check_file_access(struct file *filp, const char *caller) 226 { 227 if (filp->f_cred != current_real_cred()) { 228 pr_err_once("%s: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n", 229 caller, task_tgid_vnr(current), current->comm); 230 return -EPERM; 231 } 232 if (uaccess_kernel()) { 233 pr_err_once("%s: process %d (%s) called from kernel context, this is not allowed.\n", 234 caller, task_tgid_vnr(current), current->comm); 235 return -EACCES; 236 } 237 return 0; 238 } 239 240 static int sg_allow_access(struct file *filp, unsigned char *cmd) 241 { 242 struct sg_fd *sfp = filp->private_data; 243 244 if (sfp->parentdp->device->type == TYPE_SCANNER) 245 return 0; 246 247 return blk_verify_command(cmd, filp->f_mode); 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 ssize_t 414 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos) 415 { 416 Sg_device *sdp; 417 Sg_fd *sfp; 418 Sg_request *srp; 419 int req_pack_id = -1; 420 sg_io_hdr_t *hp; 421 struct sg_header *old_hdr = NULL; 422 int retval = 0; 423 424 /* 425 * This could cause a response to be stranded. Close the associated 426 * file descriptor to free up any resources being held. 427 */ 428 retval = sg_check_file_access(filp, __func__); 429 if (retval) 430 return retval; 431 432 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 433 return -ENXIO; 434 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 435 "sg_read: count=%d\n", (int) count)); 436 437 if (!access_ok(VERIFY_WRITE, buf, count)) 438 return -EFAULT; 439 if (sfp->force_packid && (count >= SZ_SG_HEADER)) { 440 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL); 441 if (!old_hdr) 442 return -ENOMEM; 443 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) { 444 retval = -EFAULT; 445 goto free_old_hdr; 446 } 447 if (old_hdr->reply_len < 0) { 448 if (count >= SZ_SG_IO_HDR) { 449 sg_io_hdr_t *new_hdr; 450 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL); 451 if (!new_hdr) { 452 retval = -ENOMEM; 453 goto free_old_hdr; 454 } 455 retval =__copy_from_user 456 (new_hdr, buf, SZ_SG_IO_HDR); 457 req_pack_id = new_hdr->pack_id; 458 kfree(new_hdr); 459 if (retval) { 460 retval = -EFAULT; 461 goto free_old_hdr; 462 } 463 } 464 } else 465 req_pack_id = old_hdr->pack_id; 466 } 467 srp = sg_get_rq_mark(sfp, req_pack_id); 468 if (!srp) { /* now wait on packet to arrive */ 469 if (atomic_read(&sdp->detaching)) { 470 retval = -ENODEV; 471 goto free_old_hdr; 472 } 473 if (filp->f_flags & O_NONBLOCK) { 474 retval = -EAGAIN; 475 goto free_old_hdr; 476 } 477 retval = wait_event_interruptible(sfp->read_wait, 478 (atomic_read(&sdp->detaching) || 479 (srp = sg_get_rq_mark(sfp, req_pack_id)))); 480 if (atomic_read(&sdp->detaching)) { 481 retval = -ENODEV; 482 goto free_old_hdr; 483 } 484 if (retval) { 485 /* -ERESTARTSYS as signal hit process */ 486 goto free_old_hdr; 487 } 488 } 489 if (srp->header.interface_id != '\0') { 490 retval = sg_new_read(sfp, buf, count, srp); 491 goto free_old_hdr; 492 } 493 494 hp = &srp->header; 495 if (old_hdr == NULL) { 496 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL); 497 if (! old_hdr) { 498 retval = -ENOMEM; 499 goto free_old_hdr; 500 } 501 } 502 memset(old_hdr, 0, SZ_SG_HEADER); 503 old_hdr->reply_len = (int) hp->timeout; 504 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */ 505 old_hdr->pack_id = hp->pack_id; 506 old_hdr->twelve_byte = 507 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0; 508 old_hdr->target_status = hp->masked_status; 509 old_hdr->host_status = hp->host_status; 510 old_hdr->driver_status = hp->driver_status; 511 if ((CHECK_CONDITION & hp->masked_status) || 512 (DRIVER_SENSE & hp->driver_status)) 513 memcpy(old_hdr->sense_buffer, srp->sense_b, 514 sizeof (old_hdr->sense_buffer)); 515 switch (hp->host_status) { 516 /* This setup of 'result' is for backward compatibility and is best 517 ignored by the user who should use target, host + driver status */ 518 case DID_OK: 519 case DID_PASSTHROUGH: 520 case DID_SOFT_ERROR: 521 old_hdr->result = 0; 522 break; 523 case DID_NO_CONNECT: 524 case DID_BUS_BUSY: 525 case DID_TIME_OUT: 526 old_hdr->result = EBUSY; 527 break; 528 case DID_BAD_TARGET: 529 case DID_ABORT: 530 case DID_PARITY: 531 case DID_RESET: 532 case DID_BAD_INTR: 533 old_hdr->result = EIO; 534 break; 535 case DID_ERROR: 536 old_hdr->result = (srp->sense_b[0] == 0 && 537 hp->masked_status == GOOD) ? 0 : EIO; 538 break; 539 default: 540 old_hdr->result = EIO; 541 break; 542 } 543 544 /* Now copy the result back to the user buffer. */ 545 if (count >= SZ_SG_HEADER) { 546 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) { 547 retval = -EFAULT; 548 goto free_old_hdr; 549 } 550 buf += SZ_SG_HEADER; 551 if (count > old_hdr->reply_len) 552 count = old_hdr->reply_len; 553 if (count > SZ_SG_HEADER) { 554 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) { 555 retval = -EFAULT; 556 goto free_old_hdr; 557 } 558 } 559 } else 560 count = (old_hdr->result == 0) ? 0 : -EIO; 561 sg_finish_rem_req(srp); 562 sg_remove_request(sfp, srp); 563 retval = count; 564 free_old_hdr: 565 kfree(old_hdr); 566 return retval; 567 } 568 569 static ssize_t 570 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp) 571 { 572 sg_io_hdr_t *hp = &srp->header; 573 int err = 0, err2; 574 int len; 575 576 if (count < SZ_SG_IO_HDR) { 577 err = -EINVAL; 578 goto err_out; 579 } 580 hp->sb_len_wr = 0; 581 if ((hp->mx_sb_len > 0) && hp->sbp) { 582 if ((CHECK_CONDITION & hp->masked_status) || 583 (DRIVER_SENSE & hp->driver_status)) { 584 int sb_len = SCSI_SENSE_BUFFERSIZE; 585 sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len; 586 len = 8 + (int) srp->sense_b[7]; /* Additional sense length field */ 587 len = (len > sb_len) ? sb_len : len; 588 if (copy_to_user(hp->sbp, srp->sense_b, len)) { 589 err = -EFAULT; 590 goto err_out; 591 } 592 hp->sb_len_wr = len; 593 } 594 } 595 if (hp->masked_status || hp->host_status || hp->driver_status) 596 hp->info |= SG_INFO_CHECK; 597 if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) { 598 err = -EFAULT; 599 goto err_out; 600 } 601 err_out: 602 err2 = sg_finish_rem_req(srp); 603 sg_remove_request(sfp, srp); 604 return err ? : err2 ? : count; 605 } 606 607 static ssize_t 608 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos) 609 { 610 int mxsize, cmd_size, k; 611 int input_size, blocking; 612 unsigned char opcode; 613 Sg_device *sdp; 614 Sg_fd *sfp; 615 Sg_request *srp; 616 struct sg_header old_hdr; 617 sg_io_hdr_t *hp; 618 unsigned char cmnd[SG_MAX_CDB_SIZE]; 619 int retval; 620 621 retval = sg_check_file_access(filp, __func__); 622 if (retval) 623 return retval; 624 625 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 626 return -ENXIO; 627 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 628 "sg_write: count=%d\n", (int) count)); 629 if (atomic_read(&sdp->detaching)) 630 return -ENODEV; 631 if (!((filp->f_flags & O_NONBLOCK) || 632 scsi_block_when_processing_errors(sdp->device))) 633 return -ENXIO; 634 635 if (!access_ok(VERIFY_READ, buf, count)) 636 return -EFAULT; /* protects following copy_from_user()s + get_user()s */ 637 if (count < SZ_SG_HEADER) 638 return -EIO; 639 if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER)) 640 return -EFAULT; 641 blocking = !(filp->f_flags & O_NONBLOCK); 642 if (old_hdr.reply_len < 0) 643 return sg_new_write(sfp, filp, buf, count, 644 blocking, 0, 0, NULL); 645 if (count < (SZ_SG_HEADER + 6)) 646 return -EIO; /* The minimum scsi command length is 6 bytes. */ 647 648 if (!(srp = sg_add_request(sfp))) { 649 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sdp, 650 "sg_write: queue full\n")); 651 return -EDOM; 652 } 653 buf += SZ_SG_HEADER; 654 __get_user(opcode, buf); 655 mutex_lock(&sfp->f_mutex); 656 if (sfp->next_cmd_len > 0) { 657 cmd_size = sfp->next_cmd_len; 658 sfp->next_cmd_len = 0; /* reset so only this write() effected */ 659 } else { 660 cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */ 661 if ((opcode >= 0xc0) && old_hdr.twelve_byte) 662 cmd_size = 12; 663 } 664 mutex_unlock(&sfp->f_mutex); 665 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp, 666 "sg_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size)); 667 /* Determine buffer size. */ 668 input_size = count - cmd_size; 669 mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len; 670 mxsize -= SZ_SG_HEADER; 671 input_size -= SZ_SG_HEADER; 672 if (input_size < 0) { 673 sg_remove_request(sfp, srp); 674 return -EIO; /* User did not pass enough bytes for this command. */ 675 } 676 hp = &srp->header; 677 hp->interface_id = '\0'; /* indicator of old interface tunnelled */ 678 hp->cmd_len = (unsigned char) cmd_size; 679 hp->iovec_count = 0; 680 hp->mx_sb_len = 0; 681 if (input_size > 0) 682 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ? 683 SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV; 684 else 685 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE; 686 hp->dxfer_len = mxsize; 687 if ((hp->dxfer_direction == SG_DXFER_TO_DEV) || 688 (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV)) 689 hp->dxferp = (char __user *)buf + cmd_size; 690 else 691 hp->dxferp = NULL; 692 hp->sbp = NULL; 693 hp->timeout = old_hdr.reply_len; /* structure abuse ... */ 694 hp->flags = input_size; /* structure abuse ... */ 695 hp->pack_id = old_hdr.pack_id; 696 hp->usr_ptr = NULL; 697 if (__copy_from_user(cmnd, buf, cmd_size)) 698 return -EFAULT; 699 /* 700 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV, 701 * but is is possible that the app intended SG_DXFER_TO_DEV, because there 702 * is a non-zero input_size, so emit a warning. 703 */ 704 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) { 705 printk_ratelimited(KERN_WARNING 706 "sg_write: data in/out %d/%d bytes " 707 "for SCSI command 0x%x-- guessing " 708 "data in;\n program %s not setting " 709 "count and/or reply_len properly\n", 710 old_hdr.reply_len - (int)SZ_SG_HEADER, 711 input_size, (unsigned int) cmnd[0], 712 current->comm); 713 } 714 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking); 715 return (k < 0) ? k : count; 716 } 717 718 static ssize_t 719 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf, 720 size_t count, int blocking, int read_only, int sg_io_owned, 721 Sg_request **o_srp) 722 { 723 int k; 724 Sg_request *srp; 725 sg_io_hdr_t *hp; 726 unsigned char cmnd[SG_MAX_CDB_SIZE]; 727 int timeout; 728 unsigned long ul_timeout; 729 730 if (count < SZ_SG_IO_HDR) 731 return -EINVAL; 732 if (!access_ok(VERIFY_READ, buf, count)) 733 return -EFAULT; /* protects following copy_from_user()s + get_user()s */ 734 735 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */ 736 if (!(srp = sg_add_request(sfp))) { 737 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp, 738 "sg_new_write: queue full\n")); 739 return -EDOM; 740 } 741 srp->sg_io_owned = sg_io_owned; 742 hp = &srp->header; 743 if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) { 744 sg_remove_request(sfp, srp); 745 return -EFAULT; 746 } 747 if (hp->interface_id != 'S') { 748 sg_remove_request(sfp, srp); 749 return -ENOSYS; 750 } 751 if (hp->flags & SG_FLAG_MMAP_IO) { 752 if (hp->dxfer_len > sfp->reserve.bufflen) { 753 sg_remove_request(sfp, srp); 754 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */ 755 } 756 if (hp->flags & SG_FLAG_DIRECT_IO) { 757 sg_remove_request(sfp, srp); 758 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */ 759 } 760 if (sfp->res_in_use) { 761 sg_remove_request(sfp, srp); 762 return -EBUSY; /* reserve buffer already being used */ 763 } 764 } 765 ul_timeout = msecs_to_jiffies(srp->header.timeout); 766 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX; 767 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) { 768 sg_remove_request(sfp, srp); 769 return -EMSGSIZE; 770 } 771 if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) { 772 sg_remove_request(sfp, srp); 773 return -EFAULT; /* protects following copy_from_user()s + get_user()s */ 774 } 775 if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) { 776 sg_remove_request(sfp, srp); 777 return -EFAULT; 778 } 779 if (read_only && sg_allow_access(file, cmnd)) { 780 sg_remove_request(sfp, srp); 781 return -EPERM; 782 } 783 k = sg_common_write(sfp, srp, cmnd, timeout, blocking); 784 if (k < 0) 785 return k; 786 if (o_srp) 787 *o_srp = srp; 788 return count; 789 } 790 791 static int 792 sg_common_write(Sg_fd * sfp, Sg_request * srp, 793 unsigned char *cmnd, int timeout, int blocking) 794 { 795 int k, at_head; 796 Sg_device *sdp = sfp->parentdp; 797 sg_io_hdr_t *hp = &srp->header; 798 799 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */ 800 hp->status = 0; 801 hp->masked_status = 0; 802 hp->msg_status = 0; 803 hp->info = 0; 804 hp->host_status = 0; 805 hp->driver_status = 0; 806 hp->resid = 0; 807 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 808 "sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n", 809 (int) cmnd[0], (int) hp->cmd_len)); 810 811 if (hp->dxfer_len >= SZ_256M) 812 return -EINVAL; 813 814 k = sg_start_req(srp, cmnd); 815 if (k) { 816 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp, 817 "sg_common_write: start_req err=%d\n", k)); 818 sg_finish_rem_req(srp); 819 sg_remove_request(sfp, srp); 820 return k; /* probably out of space --> ENOMEM */ 821 } 822 if (atomic_read(&sdp->detaching)) { 823 if (srp->bio) { 824 scsi_req_free_cmd(scsi_req(srp->rq)); 825 blk_end_request_all(srp->rq, BLK_STS_IOERR); 826 srp->rq = NULL; 827 } 828 829 sg_finish_rem_req(srp); 830 sg_remove_request(sfp, srp); 831 return -ENODEV; 832 } 833 834 hp->duration = jiffies_to_msecs(jiffies); 835 if (hp->interface_id != '\0' && /* v3 (or later) interface */ 836 (SG_FLAG_Q_AT_TAIL & hp->flags)) 837 at_head = 0; 838 else 839 at_head = 1; 840 841 srp->rq->timeout = timeout; 842 kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */ 843 blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk, 844 srp->rq, at_head, sg_rq_end_io); 845 return 0; 846 } 847 848 static int srp_done(Sg_fd *sfp, Sg_request *srp) 849 { 850 unsigned long flags; 851 int ret; 852 853 read_lock_irqsave(&sfp->rq_list_lock, flags); 854 ret = srp->done; 855 read_unlock_irqrestore(&sfp->rq_list_lock, flags); 856 return ret; 857 } 858 859 static int max_sectors_bytes(struct request_queue *q) 860 { 861 unsigned int max_sectors = queue_max_sectors(q); 862 863 max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9); 864 865 return max_sectors << 9; 866 } 867 868 static void 869 sg_fill_request_table(Sg_fd *sfp, sg_req_info_t *rinfo) 870 { 871 Sg_request *srp; 872 int val; 873 unsigned int ms; 874 875 val = 0; 876 list_for_each_entry(srp, &sfp->rq_list, entry) { 877 if (val >= SG_MAX_QUEUE) 878 break; 879 rinfo[val].req_state = srp->done + 1; 880 rinfo[val].problem = 881 srp->header.masked_status & 882 srp->header.host_status & 883 srp->header.driver_status; 884 if (srp->done) 885 rinfo[val].duration = 886 srp->header.duration; 887 else { 888 ms = jiffies_to_msecs(jiffies); 889 rinfo[val].duration = 890 (ms > srp->header.duration) ? 891 (ms - srp->header.duration) : 0; 892 } 893 rinfo[val].orphan = srp->orphan; 894 rinfo[val].sg_io_owned = srp->sg_io_owned; 895 rinfo[val].pack_id = srp->header.pack_id; 896 rinfo[val].usr_ptr = srp->header.usr_ptr; 897 val++; 898 } 899 } 900 901 static long 902 sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg) 903 { 904 void __user *p = (void __user *)arg; 905 int __user *ip = p; 906 int result, val, read_only; 907 Sg_device *sdp; 908 Sg_fd *sfp; 909 Sg_request *srp; 910 unsigned long iflags; 911 912 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 913 return -ENXIO; 914 915 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 916 "sg_ioctl: cmd=0x%x\n", (int) cmd_in)); 917 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE)); 918 919 switch (cmd_in) { 920 case SG_IO: 921 if (atomic_read(&sdp->detaching)) 922 return -ENODEV; 923 if (!scsi_block_when_processing_errors(sdp->device)) 924 return -ENXIO; 925 if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR)) 926 return -EFAULT; 927 result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR, 928 1, read_only, 1, &srp); 929 if (result < 0) 930 return result; 931 result = wait_event_interruptible(sfp->read_wait, 932 (srp_done(sfp, srp) || atomic_read(&sdp->detaching))); 933 if (atomic_read(&sdp->detaching)) 934 return -ENODEV; 935 write_lock_irq(&sfp->rq_list_lock); 936 if (srp->done) { 937 srp->done = 2; 938 write_unlock_irq(&sfp->rq_list_lock); 939 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp); 940 return (result < 0) ? result : 0; 941 } 942 srp->orphan = 1; 943 write_unlock_irq(&sfp->rq_list_lock); 944 return result; /* -ERESTARTSYS because signal hit process */ 945 case SG_SET_TIMEOUT: 946 result = get_user(val, ip); 947 if (result) 948 return result; 949 if (val < 0) 950 return -EIO; 951 if (val >= mult_frac((s64)INT_MAX, USER_HZ, HZ)) 952 val = min_t(s64, mult_frac((s64)INT_MAX, USER_HZ, HZ), 953 INT_MAX); 954 sfp->timeout_user = val; 955 sfp->timeout = mult_frac(val, HZ, USER_HZ); 956 957 return 0; 958 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */ 959 /* strange ..., for backward compatibility */ 960 return sfp->timeout_user; 961 case SG_SET_FORCE_LOW_DMA: 962 /* 963 * N.B. This ioctl never worked properly, but failed to 964 * return an error value. So returning '0' to keep compability 965 * with legacy applications. 966 */ 967 return 0; 968 case SG_GET_LOW_DMA: 969 return put_user((int) sdp->device->host->unchecked_isa_dma, ip); 970 case SG_GET_SCSI_ID: 971 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t))) 972 return -EFAULT; 973 else { 974 sg_scsi_id_t __user *sg_idp = p; 975 976 if (atomic_read(&sdp->detaching)) 977 return -ENODEV; 978 __put_user((int) sdp->device->host->host_no, 979 &sg_idp->host_no); 980 __put_user((int) sdp->device->channel, 981 &sg_idp->channel); 982 __put_user((int) sdp->device->id, &sg_idp->scsi_id); 983 __put_user((int) sdp->device->lun, &sg_idp->lun); 984 __put_user((int) sdp->device->type, &sg_idp->scsi_type); 985 __put_user((short) sdp->device->host->cmd_per_lun, 986 &sg_idp->h_cmd_per_lun); 987 __put_user((short) sdp->device->queue_depth, 988 &sg_idp->d_queue_depth); 989 __put_user(0, &sg_idp->unused[0]); 990 __put_user(0, &sg_idp->unused[1]); 991 return 0; 992 } 993 case SG_SET_FORCE_PACK_ID: 994 result = get_user(val, ip); 995 if (result) 996 return result; 997 sfp->force_packid = val ? 1 : 0; 998 return 0; 999 case SG_GET_PACK_ID: 1000 if (!access_ok(VERIFY_WRITE, ip, sizeof (int))) 1001 return -EFAULT; 1002 read_lock_irqsave(&sfp->rq_list_lock, iflags); 1003 list_for_each_entry(srp, &sfp->rq_list, entry) { 1004 if ((1 == srp->done) && (!srp->sg_io_owned)) { 1005 read_unlock_irqrestore(&sfp->rq_list_lock, 1006 iflags); 1007 __put_user(srp->header.pack_id, ip); 1008 return 0; 1009 } 1010 } 1011 read_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1012 __put_user(-1, ip); 1013 return 0; 1014 case SG_GET_NUM_WAITING: 1015 read_lock_irqsave(&sfp->rq_list_lock, iflags); 1016 val = 0; 1017 list_for_each_entry(srp, &sfp->rq_list, entry) { 1018 if ((1 == srp->done) && (!srp->sg_io_owned)) 1019 ++val; 1020 } 1021 read_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1022 return put_user(val, ip); 1023 case SG_GET_SG_TABLESIZE: 1024 return put_user(sdp->sg_tablesize, ip); 1025 case SG_SET_RESERVED_SIZE: 1026 result = get_user(val, ip); 1027 if (result) 1028 return result; 1029 if (val < 0) 1030 return -EINVAL; 1031 val = min_t(int, val, 1032 max_sectors_bytes(sdp->device->request_queue)); 1033 mutex_lock(&sfp->f_mutex); 1034 if (val != sfp->reserve.bufflen) { 1035 if (sfp->mmap_called || 1036 sfp->res_in_use) { 1037 mutex_unlock(&sfp->f_mutex); 1038 return -EBUSY; 1039 } 1040 1041 sg_remove_scat(sfp, &sfp->reserve); 1042 sg_build_reserve(sfp, val); 1043 } 1044 mutex_unlock(&sfp->f_mutex); 1045 return 0; 1046 case SG_GET_RESERVED_SIZE: 1047 val = min_t(int, sfp->reserve.bufflen, 1048 max_sectors_bytes(sdp->device->request_queue)); 1049 return put_user(val, ip); 1050 case SG_SET_COMMAND_Q: 1051 result = get_user(val, ip); 1052 if (result) 1053 return result; 1054 sfp->cmd_q = val ? 1 : 0; 1055 return 0; 1056 case SG_GET_COMMAND_Q: 1057 return put_user((int) sfp->cmd_q, ip); 1058 case SG_SET_KEEP_ORPHAN: 1059 result = get_user(val, ip); 1060 if (result) 1061 return result; 1062 sfp->keep_orphan = val; 1063 return 0; 1064 case SG_GET_KEEP_ORPHAN: 1065 return put_user((int) sfp->keep_orphan, ip); 1066 case SG_NEXT_CMD_LEN: 1067 result = get_user(val, ip); 1068 if (result) 1069 return result; 1070 if (val > SG_MAX_CDB_SIZE) 1071 return -ENOMEM; 1072 sfp->next_cmd_len = (val > 0) ? val : 0; 1073 return 0; 1074 case SG_GET_VERSION_NUM: 1075 return put_user(sg_version_num, ip); 1076 case SG_GET_ACCESS_COUNT: 1077 /* faked - we don't have a real access count anymore */ 1078 val = (sdp->device ? 1 : 0); 1079 return put_user(val, ip); 1080 case SG_GET_REQUEST_TABLE: 1081 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE)) 1082 return -EFAULT; 1083 else { 1084 sg_req_info_t *rinfo; 1085 1086 rinfo = kcalloc(SG_MAX_QUEUE, SZ_SG_REQ_INFO, 1087 GFP_KERNEL); 1088 if (!rinfo) 1089 return -ENOMEM; 1090 read_lock_irqsave(&sfp->rq_list_lock, iflags); 1091 sg_fill_request_table(sfp, rinfo); 1092 read_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1093 result = __copy_to_user(p, rinfo, 1094 SZ_SG_REQ_INFO * SG_MAX_QUEUE); 1095 result = result ? -EFAULT : 0; 1096 kfree(rinfo); 1097 return result; 1098 } 1099 case SG_EMULATED_HOST: 1100 if (atomic_read(&sdp->detaching)) 1101 return -ENODEV; 1102 return put_user(sdp->device->host->hostt->emulated, ip); 1103 case SCSI_IOCTL_SEND_COMMAND: 1104 if (atomic_read(&sdp->detaching)) 1105 return -ENODEV; 1106 if (read_only) { 1107 unsigned char opcode = WRITE_6; 1108 Scsi_Ioctl_Command __user *siocp = p; 1109 1110 if (copy_from_user(&opcode, siocp->data, 1)) 1111 return -EFAULT; 1112 if (sg_allow_access(filp, &opcode)) 1113 return -EPERM; 1114 } 1115 return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p); 1116 case SG_SET_DEBUG: 1117 result = get_user(val, ip); 1118 if (result) 1119 return result; 1120 sdp->sgdebug = (char) val; 1121 return 0; 1122 case BLKSECTGET: 1123 return put_user(max_sectors_bytes(sdp->device->request_queue), 1124 ip); 1125 case BLKTRACESETUP: 1126 return blk_trace_setup(sdp->device->request_queue, 1127 sdp->disk->disk_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 return scsi_ioctl(sdp->device, cmd_in, p); 1155 } 1156 1157 #ifdef CONFIG_COMPAT 1158 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg) 1159 { 1160 Sg_device *sdp; 1161 Sg_fd *sfp; 1162 struct scsi_device *sdev; 1163 1164 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 1165 return -ENXIO; 1166 1167 sdev = sdp->device; 1168 if (sdev->host->hostt->compat_ioctl) { 1169 int ret; 1170 1171 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg); 1172 1173 return ret; 1174 } 1175 1176 return -ENOIOCTLCMD; 1177 } 1178 #endif 1179 1180 static __poll_t 1181 sg_poll(struct file *filp, poll_table * wait) 1182 { 1183 __poll_t res = 0; 1184 Sg_device *sdp; 1185 Sg_fd *sfp; 1186 Sg_request *srp; 1187 int count = 0; 1188 unsigned long iflags; 1189 1190 sfp = filp->private_data; 1191 if (!sfp) 1192 return EPOLLERR; 1193 sdp = sfp->parentdp; 1194 if (!sdp) 1195 return EPOLLERR; 1196 poll_wait(filp, &sfp->read_wait, wait); 1197 read_lock_irqsave(&sfp->rq_list_lock, iflags); 1198 list_for_each_entry(srp, &sfp->rq_list, entry) { 1199 /* if any read waiting, flag it */ 1200 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned)) 1201 res = EPOLLIN | EPOLLRDNORM; 1202 ++count; 1203 } 1204 read_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1205 1206 if (atomic_read(&sdp->detaching)) 1207 res |= EPOLLHUP; 1208 else if (!sfp->cmd_q) { 1209 if (0 == count) 1210 res |= EPOLLOUT | EPOLLWRNORM; 1211 } else if (count < SG_MAX_QUEUE) 1212 res |= EPOLLOUT | EPOLLWRNORM; 1213 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 1214 "sg_poll: res=0x%x\n", (__force u32) res)); 1215 return res; 1216 } 1217 1218 static int 1219 sg_fasync(int fd, struct file *filp, int mode) 1220 { 1221 Sg_device *sdp; 1222 Sg_fd *sfp; 1223 1224 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) 1225 return -ENXIO; 1226 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 1227 "sg_fasync: mode=%d\n", mode)); 1228 1229 return fasync_helper(fd, filp, mode, &sfp->async_qp); 1230 } 1231 1232 static vm_fault_t 1233 sg_vma_fault(struct vm_fault *vmf) 1234 { 1235 struct vm_area_struct *vma = vmf->vma; 1236 Sg_fd *sfp; 1237 unsigned long offset, len, sa; 1238 Sg_scatter_hold *rsv_schp; 1239 int k, length; 1240 1241 if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data))) 1242 return VM_FAULT_SIGBUS; 1243 rsv_schp = &sfp->reserve; 1244 offset = vmf->pgoff << PAGE_SHIFT; 1245 if (offset >= rsv_schp->bufflen) 1246 return VM_FAULT_SIGBUS; 1247 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp, 1248 "sg_vma_fault: offset=%lu, scatg=%d\n", 1249 offset, rsv_schp->k_use_sg)); 1250 sa = vma->vm_start; 1251 length = 1 << (PAGE_SHIFT + rsv_schp->page_order); 1252 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) { 1253 len = vma->vm_end - sa; 1254 len = (len < length) ? len : length; 1255 if (offset < len) { 1256 struct page *page = nth_page(rsv_schp->pages[k], 1257 offset >> PAGE_SHIFT); 1258 get_page(page); /* increment page count */ 1259 vmf->page = page; 1260 return 0; /* success */ 1261 } 1262 sa += len; 1263 offset -= len; 1264 } 1265 1266 return VM_FAULT_SIGBUS; 1267 } 1268 1269 static const struct vm_operations_struct sg_mmap_vm_ops = { 1270 .fault = sg_vma_fault, 1271 }; 1272 1273 static int 1274 sg_mmap(struct file *filp, struct vm_area_struct *vma) 1275 { 1276 Sg_fd *sfp; 1277 unsigned long req_sz, len, sa; 1278 Sg_scatter_hold *rsv_schp; 1279 int k, length; 1280 int ret = 0; 1281 1282 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data))) 1283 return -ENXIO; 1284 req_sz = vma->vm_end - vma->vm_start; 1285 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp, 1286 "sg_mmap starting, vm_start=%p, len=%d\n", 1287 (void *) vma->vm_start, (int) req_sz)); 1288 if (vma->vm_pgoff) 1289 return -EINVAL; /* want no offset */ 1290 rsv_schp = &sfp->reserve; 1291 mutex_lock(&sfp->f_mutex); 1292 if (req_sz > rsv_schp->bufflen) { 1293 ret = -ENOMEM; /* cannot map more than reserved buffer */ 1294 goto out; 1295 } 1296 1297 sa = vma->vm_start; 1298 length = 1 << (PAGE_SHIFT + rsv_schp->page_order); 1299 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) { 1300 len = vma->vm_end - sa; 1301 len = (len < length) ? len : length; 1302 sa += len; 1303 } 1304 1305 sfp->mmap_called = 1; 1306 vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP; 1307 vma->vm_private_data = sfp; 1308 vma->vm_ops = &sg_mmap_vm_ops; 1309 out: 1310 mutex_unlock(&sfp->f_mutex); 1311 return ret; 1312 } 1313 1314 static void 1315 sg_rq_end_io_usercontext(struct work_struct *work) 1316 { 1317 struct sg_request *srp = container_of(work, struct sg_request, ew.work); 1318 struct sg_fd *sfp = srp->parentfp; 1319 1320 sg_finish_rem_req(srp); 1321 sg_remove_request(sfp, srp); 1322 kref_put(&sfp->f_ref, sg_remove_sfp); 1323 } 1324 1325 /* 1326 * This function is a "bottom half" handler that is called by the mid 1327 * level when a command is completed (or has failed). 1328 */ 1329 static void 1330 sg_rq_end_io(struct request *rq, blk_status_t status) 1331 { 1332 struct sg_request *srp = rq->end_io_data; 1333 struct scsi_request *req = scsi_req(rq); 1334 Sg_device *sdp; 1335 Sg_fd *sfp; 1336 unsigned long iflags; 1337 unsigned int ms; 1338 char *sense; 1339 int result, resid, done = 1; 1340 1341 if (WARN_ON(srp->done != 0)) 1342 return; 1343 1344 sfp = srp->parentfp; 1345 if (WARN_ON(sfp == NULL)) 1346 return; 1347 1348 sdp = sfp->parentdp; 1349 if (unlikely(atomic_read(&sdp->detaching))) 1350 pr_info("%s: device detaching\n", __func__); 1351 1352 sense = req->sense; 1353 result = req->result; 1354 resid = req->resid_len; 1355 1356 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp, 1357 "sg_cmd_done: pack_id=%d, res=0x%x\n", 1358 srp->header.pack_id, result)); 1359 srp->header.resid = resid; 1360 ms = jiffies_to_msecs(jiffies); 1361 srp->header.duration = (ms > srp->header.duration) ? 1362 (ms - srp->header.duration) : 0; 1363 if (0 != result) { 1364 struct scsi_sense_hdr sshdr; 1365 1366 srp->header.status = 0xff & result; 1367 srp->header.masked_status = status_byte(result); 1368 srp->header.msg_status = msg_byte(result); 1369 srp->header.host_status = host_byte(result); 1370 srp->header.driver_status = driver_byte(result); 1371 if ((sdp->sgdebug > 0) && 1372 ((CHECK_CONDITION == srp->header.masked_status) || 1373 (COMMAND_TERMINATED == srp->header.masked_status))) 1374 __scsi_print_sense(sdp->device, __func__, sense, 1375 SCSI_SENSE_BUFFERSIZE); 1376 1377 /* Following if statement is a patch supplied by Eric Youngdale */ 1378 if (driver_byte(result) != 0 1379 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr) 1380 && !scsi_sense_is_deferred(&sshdr) 1381 && sshdr.sense_key == UNIT_ATTENTION 1382 && sdp->device->removable) { 1383 /* Detected possible disc change. Set the bit - this */ 1384 /* may be used if there are filesystems using this device */ 1385 sdp->device->changed = 1; 1386 } 1387 } 1388 1389 if (req->sense_len) 1390 memcpy(srp->sense_b, req->sense, SCSI_SENSE_BUFFERSIZE); 1391 1392 /* Rely on write phase to clean out srp status values, so no "else" */ 1393 1394 /* 1395 * Free the request as soon as it is complete so that its resources 1396 * can be reused without waiting for userspace to read() the 1397 * result. But keep the associated bio (if any) around until 1398 * blk_rq_unmap_user() can be called from user context. 1399 */ 1400 srp->rq = NULL; 1401 scsi_req_free_cmd(scsi_req(rq)); 1402 __blk_put_request(rq->q, rq); 1403 1404 write_lock_irqsave(&sfp->rq_list_lock, iflags); 1405 if (unlikely(srp->orphan)) { 1406 if (sfp->keep_orphan) 1407 srp->sg_io_owned = 0; 1408 else 1409 done = 0; 1410 } 1411 srp->done = done; 1412 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 1413 1414 if (likely(done)) { 1415 /* Now wake up any sg_read() that is waiting for this 1416 * packet. 1417 */ 1418 wake_up_interruptible(&sfp->read_wait); 1419 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN); 1420 kref_put(&sfp->f_ref, sg_remove_sfp); 1421 } else { 1422 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext); 1423 schedule_work(&srp->ew.work); 1424 } 1425 } 1426 1427 static const struct file_operations sg_fops = { 1428 .owner = THIS_MODULE, 1429 .read = sg_read, 1430 .write = sg_write, 1431 .poll = sg_poll, 1432 .unlocked_ioctl = sg_ioctl, 1433 #ifdef CONFIG_COMPAT 1434 .compat_ioctl = sg_compat_ioctl, 1435 #endif 1436 .open = sg_open, 1437 .mmap = sg_mmap, 1438 .release = sg_release, 1439 .fasync = sg_fasync, 1440 .llseek = no_llseek, 1441 }; 1442 1443 static struct class *sg_sysfs_class; 1444 1445 static int sg_sysfs_valid = 0; 1446 1447 static Sg_device * 1448 sg_alloc(struct gendisk *disk, struct scsi_device *scsidp) 1449 { 1450 struct request_queue *q = scsidp->request_queue; 1451 Sg_device *sdp; 1452 unsigned long iflags; 1453 int error; 1454 u32 k; 1455 1456 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL); 1457 if (!sdp) { 1458 sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device " 1459 "failure\n", __func__); 1460 return ERR_PTR(-ENOMEM); 1461 } 1462 1463 idr_preload(GFP_KERNEL); 1464 write_lock_irqsave(&sg_index_lock, iflags); 1465 1466 error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT); 1467 if (error < 0) { 1468 if (error == -ENOSPC) { 1469 sdev_printk(KERN_WARNING, scsidp, 1470 "Unable to attach sg device type=%d, minor number exceeds %d\n", 1471 scsidp->type, SG_MAX_DEVS - 1); 1472 error = -ENODEV; 1473 } else { 1474 sdev_printk(KERN_WARNING, scsidp, "%s: idr " 1475 "allocation Sg_device failure: %d\n", 1476 __func__, error); 1477 } 1478 goto out_unlock; 1479 } 1480 k = error; 1481 1482 SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp, 1483 "sg_alloc: dev=%d \n", k)); 1484 sprintf(disk->disk_name, "sg%d", k); 1485 disk->first_minor = k; 1486 sdp->disk = disk; 1487 sdp->device = scsidp; 1488 mutex_init(&sdp->open_rel_lock); 1489 INIT_LIST_HEAD(&sdp->sfds); 1490 init_waitqueue_head(&sdp->open_wait); 1491 atomic_set(&sdp->detaching, 0); 1492 rwlock_init(&sdp->sfd_lock); 1493 sdp->sg_tablesize = queue_max_segments(q); 1494 sdp->index = k; 1495 kref_init(&sdp->d_ref); 1496 error = 0; 1497 1498 out_unlock: 1499 write_unlock_irqrestore(&sg_index_lock, iflags); 1500 idr_preload_end(); 1501 1502 if (error) { 1503 kfree(sdp); 1504 return ERR_PTR(error); 1505 } 1506 return sdp; 1507 } 1508 1509 static int 1510 sg_add_device(struct device *cl_dev, struct class_interface *cl_intf) 1511 { 1512 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent); 1513 struct gendisk *disk; 1514 Sg_device *sdp = NULL; 1515 struct cdev * cdev = NULL; 1516 int error; 1517 unsigned long iflags; 1518 1519 disk = alloc_disk(1); 1520 if (!disk) { 1521 pr_warn("%s: alloc_disk failed\n", __func__); 1522 return -ENOMEM; 1523 } 1524 disk->major = SCSI_GENERIC_MAJOR; 1525 1526 error = -ENOMEM; 1527 cdev = cdev_alloc(); 1528 if (!cdev) { 1529 pr_warn("%s: cdev_alloc failed\n", __func__); 1530 goto out; 1531 } 1532 cdev->owner = THIS_MODULE; 1533 cdev->ops = &sg_fops; 1534 1535 sdp = sg_alloc(disk, scsidp); 1536 if (IS_ERR(sdp)) { 1537 pr_warn("%s: sg_alloc failed\n", __func__); 1538 error = PTR_ERR(sdp); 1539 goto out; 1540 } 1541 1542 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1); 1543 if (error) 1544 goto cdev_add_err; 1545 1546 sdp->cdev = cdev; 1547 if (sg_sysfs_valid) { 1548 struct device *sg_class_member; 1549 1550 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent, 1551 MKDEV(SCSI_GENERIC_MAJOR, 1552 sdp->index), 1553 sdp, "%s", disk->disk_name); 1554 if (IS_ERR(sg_class_member)) { 1555 pr_err("%s: device_create failed\n", __func__); 1556 error = PTR_ERR(sg_class_member); 1557 goto cdev_add_err; 1558 } 1559 error = sysfs_create_link(&scsidp->sdev_gendev.kobj, 1560 &sg_class_member->kobj, "generic"); 1561 if (error) 1562 pr_err("%s: unable to make symlink 'generic' back " 1563 "to sg%d\n", __func__, sdp->index); 1564 } else 1565 pr_warn("%s: sg_sys Invalid\n", __func__); 1566 1567 sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d " 1568 "type %d\n", sdp->index, scsidp->type); 1569 1570 dev_set_drvdata(cl_dev, sdp); 1571 1572 return 0; 1573 1574 cdev_add_err: 1575 write_lock_irqsave(&sg_index_lock, iflags); 1576 idr_remove(&sg_index_idr, sdp->index); 1577 write_unlock_irqrestore(&sg_index_lock, iflags); 1578 kfree(sdp); 1579 1580 out: 1581 put_disk(disk); 1582 if (cdev) 1583 cdev_del(cdev); 1584 return error; 1585 } 1586 1587 static void 1588 sg_device_destroy(struct kref *kref) 1589 { 1590 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref); 1591 unsigned long flags; 1592 1593 /* CAUTION! Note that the device can still be found via idr_find() 1594 * even though the refcount is 0. Therefore, do idr_remove() BEFORE 1595 * any other cleanup. 1596 */ 1597 1598 write_lock_irqsave(&sg_index_lock, flags); 1599 idr_remove(&sg_index_idr, sdp->index); 1600 write_unlock_irqrestore(&sg_index_lock, flags); 1601 1602 SCSI_LOG_TIMEOUT(3, 1603 sg_printk(KERN_INFO, sdp, "sg_device_destroy\n")); 1604 1605 put_disk(sdp->disk); 1606 kfree(sdp); 1607 } 1608 1609 static void 1610 sg_remove_device(struct device *cl_dev, struct class_interface *cl_intf) 1611 { 1612 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent); 1613 Sg_device *sdp = dev_get_drvdata(cl_dev); 1614 unsigned long iflags; 1615 Sg_fd *sfp; 1616 int val; 1617 1618 if (!sdp) 1619 return; 1620 /* want sdp->detaching non-zero as soon as possible */ 1621 val = atomic_inc_return(&sdp->detaching); 1622 if (val > 1) 1623 return; /* only want to do following once per device */ 1624 1625 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 1626 "%s\n", __func__)); 1627 1628 read_lock_irqsave(&sdp->sfd_lock, iflags); 1629 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) { 1630 wake_up_interruptible_all(&sfp->read_wait); 1631 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP); 1632 } 1633 wake_up_interruptible_all(&sdp->open_wait); 1634 read_unlock_irqrestore(&sdp->sfd_lock, iflags); 1635 1636 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic"); 1637 device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index)); 1638 cdev_del(sdp->cdev); 1639 sdp->cdev = NULL; 1640 1641 kref_put(&sdp->d_ref, sg_device_destroy); 1642 } 1643 1644 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR); 1645 module_param_named(def_reserved_size, def_reserved_size, int, 1646 S_IRUGO | S_IWUSR); 1647 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR); 1648 1649 MODULE_AUTHOR("Douglas Gilbert"); 1650 MODULE_DESCRIPTION("SCSI generic (sg) driver"); 1651 MODULE_LICENSE("GPL"); 1652 MODULE_VERSION(SG_VERSION_STR); 1653 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR); 1654 1655 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element " 1656 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))"); 1657 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd"); 1658 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))"); 1659 1660 static int __init 1661 init_sg(void) 1662 { 1663 int rc; 1664 1665 if (scatter_elem_sz < PAGE_SIZE) { 1666 scatter_elem_sz = PAGE_SIZE; 1667 scatter_elem_sz_prev = scatter_elem_sz; 1668 } 1669 if (def_reserved_size >= 0) 1670 sg_big_buff = def_reserved_size; 1671 else 1672 def_reserved_size = sg_big_buff; 1673 1674 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), 1675 SG_MAX_DEVS, "sg"); 1676 if (rc) 1677 return rc; 1678 sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic"); 1679 if ( IS_ERR(sg_sysfs_class) ) { 1680 rc = PTR_ERR(sg_sysfs_class); 1681 goto err_out; 1682 } 1683 sg_sysfs_valid = 1; 1684 rc = scsi_register_interface(&sg_interface); 1685 if (0 == rc) { 1686 #ifdef CONFIG_SCSI_PROC_FS 1687 sg_proc_init(); 1688 #endif /* CONFIG_SCSI_PROC_FS */ 1689 return 0; 1690 } 1691 class_destroy(sg_sysfs_class); 1692 err_out: 1693 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS); 1694 return rc; 1695 } 1696 1697 static void __exit 1698 exit_sg(void) 1699 { 1700 #ifdef CONFIG_SCSI_PROC_FS 1701 remove_proc_subtree("scsi/sg", NULL); 1702 #endif /* CONFIG_SCSI_PROC_FS */ 1703 scsi_unregister_interface(&sg_interface); 1704 class_destroy(sg_sysfs_class); 1705 sg_sysfs_valid = 0; 1706 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), 1707 SG_MAX_DEVS); 1708 idr_destroy(&sg_index_idr); 1709 } 1710 1711 static int 1712 sg_start_req(Sg_request *srp, unsigned char *cmd) 1713 { 1714 int res; 1715 struct request *rq; 1716 struct scsi_request *req; 1717 Sg_fd *sfp = srp->parentfp; 1718 sg_io_hdr_t *hp = &srp->header; 1719 int dxfer_len = (int) hp->dxfer_len; 1720 int dxfer_dir = hp->dxfer_direction; 1721 unsigned int iov_count = hp->iovec_count; 1722 Sg_scatter_hold *req_schp = &srp->data; 1723 Sg_scatter_hold *rsv_schp = &sfp->reserve; 1724 struct request_queue *q = sfp->parentdp->device->request_queue; 1725 struct rq_map_data *md, map_data; 1726 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ; 1727 unsigned char *long_cmdp = NULL; 1728 1729 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 1730 "sg_start_req: dxfer_len=%d\n", 1731 dxfer_len)); 1732 1733 if (hp->cmd_len > BLK_MAX_CDB) { 1734 long_cmdp = kzalloc(hp->cmd_len, GFP_KERNEL); 1735 if (!long_cmdp) 1736 return -ENOMEM; 1737 } 1738 1739 /* 1740 * NOTE 1741 * 1742 * With scsi-mq enabled, there are a fixed number of preallocated 1743 * requests equal in number to shost->can_queue. If all of the 1744 * preallocated requests are already in use, then blk_get_request() 1745 * will sleep until an active command completes, freeing up a request. 1746 * Although waiting in an asynchronous interface is less than ideal, we 1747 * do not want to use BLK_MQ_REQ_NOWAIT here because userspace might 1748 * not expect an EWOULDBLOCK from this condition. 1749 */ 1750 rq = blk_get_request(q, hp->dxfer_direction == SG_DXFER_TO_DEV ? 1751 REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, 0); 1752 if (IS_ERR(rq)) { 1753 kfree(long_cmdp); 1754 return PTR_ERR(rq); 1755 } 1756 req = scsi_req(rq); 1757 1758 if (hp->cmd_len > BLK_MAX_CDB) 1759 req->cmd = long_cmdp; 1760 memcpy(req->cmd, cmd, hp->cmd_len); 1761 req->cmd_len = hp->cmd_len; 1762 1763 srp->rq = rq; 1764 rq->end_io_data = srp; 1765 req->retries = SG_DEFAULT_RETRIES; 1766 1767 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE)) 1768 return 0; 1769 1770 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO && 1771 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count && 1772 !sfp->parentdp->device->host->unchecked_isa_dma && 1773 blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len)) 1774 md = NULL; 1775 else 1776 md = &map_data; 1777 1778 if (md) { 1779 mutex_lock(&sfp->f_mutex); 1780 if (dxfer_len <= rsv_schp->bufflen && 1781 !sfp->res_in_use) { 1782 sfp->res_in_use = 1; 1783 sg_link_reserve(sfp, srp, dxfer_len); 1784 } else if (hp->flags & SG_FLAG_MMAP_IO) { 1785 res = -EBUSY; /* sfp->res_in_use == 1 */ 1786 if (dxfer_len > rsv_schp->bufflen) 1787 res = -ENOMEM; 1788 mutex_unlock(&sfp->f_mutex); 1789 return res; 1790 } else { 1791 res = sg_build_indirect(req_schp, sfp, dxfer_len); 1792 if (res) { 1793 mutex_unlock(&sfp->f_mutex); 1794 return res; 1795 } 1796 } 1797 mutex_unlock(&sfp->f_mutex); 1798 1799 md->pages = req_schp->pages; 1800 md->page_order = req_schp->page_order; 1801 md->nr_entries = req_schp->k_use_sg; 1802 md->offset = 0; 1803 md->null_mapped = hp->dxferp ? 0 : 1; 1804 if (dxfer_dir == SG_DXFER_TO_FROM_DEV) 1805 md->from_user = 1; 1806 else 1807 md->from_user = 0; 1808 } 1809 1810 if (iov_count) { 1811 struct iovec *iov = NULL; 1812 struct iov_iter i; 1813 1814 res = import_iovec(rw, hp->dxferp, iov_count, 0, &iov, &i); 1815 if (res < 0) 1816 return res; 1817 1818 iov_iter_truncate(&i, hp->dxfer_len); 1819 if (!iov_iter_count(&i)) { 1820 kfree(iov); 1821 return -EINVAL; 1822 } 1823 1824 res = blk_rq_map_user_iov(q, rq, md, &i, GFP_ATOMIC); 1825 kfree(iov); 1826 } else 1827 res = blk_rq_map_user(q, rq, md, hp->dxferp, 1828 hp->dxfer_len, GFP_ATOMIC); 1829 1830 if (!res) { 1831 srp->bio = rq->bio; 1832 1833 if (!md) { 1834 req_schp->dio_in_use = 1; 1835 hp->info |= SG_INFO_DIRECT_IO; 1836 } 1837 } 1838 return res; 1839 } 1840 1841 static int 1842 sg_finish_rem_req(Sg_request *srp) 1843 { 1844 int ret = 0; 1845 1846 Sg_fd *sfp = srp->parentfp; 1847 Sg_scatter_hold *req_schp = &srp->data; 1848 1849 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 1850 "sg_finish_rem_req: res_used=%d\n", 1851 (int) srp->res_used)); 1852 if (srp->bio) 1853 ret = blk_rq_unmap_user(srp->bio); 1854 1855 if (srp->rq) { 1856 scsi_req_free_cmd(scsi_req(srp->rq)); 1857 blk_put_request(srp->rq); 1858 } 1859 1860 if (srp->res_used) 1861 sg_unlink_reserve(sfp, srp); 1862 else 1863 sg_remove_scat(sfp, req_schp); 1864 1865 return ret; 1866 } 1867 1868 static int 1869 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize) 1870 { 1871 int sg_bufflen = tablesize * sizeof(struct page *); 1872 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN; 1873 1874 schp->pages = kzalloc(sg_bufflen, gfp_flags); 1875 if (!schp->pages) 1876 return -ENOMEM; 1877 schp->sglist_len = sg_bufflen; 1878 return tablesize; /* number of scat_gath elements allocated */ 1879 } 1880 1881 static int 1882 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size) 1883 { 1884 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems; 1885 int sg_tablesize = sfp->parentdp->sg_tablesize; 1886 int blk_size = buff_size, order; 1887 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN; 1888 struct sg_device *sdp = sfp->parentdp; 1889 1890 if (blk_size < 0) 1891 return -EFAULT; 1892 if (0 == blk_size) 1893 ++blk_size; /* don't know why */ 1894 /* round request up to next highest SG_SECTOR_SZ byte boundary */ 1895 blk_size = ALIGN(blk_size, SG_SECTOR_SZ); 1896 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 1897 "sg_build_indirect: buff_size=%d, blk_size=%d\n", 1898 buff_size, blk_size)); 1899 1900 /* N.B. ret_sz carried into this block ... */ 1901 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize); 1902 if (mx_sc_elems < 0) 1903 return mx_sc_elems; /* most likely -ENOMEM */ 1904 1905 num = scatter_elem_sz; 1906 if (unlikely(num != scatter_elem_sz_prev)) { 1907 if (num < PAGE_SIZE) { 1908 scatter_elem_sz = PAGE_SIZE; 1909 scatter_elem_sz_prev = PAGE_SIZE; 1910 } else 1911 scatter_elem_sz_prev = num; 1912 } 1913 1914 if (sdp->device->host->unchecked_isa_dma) 1915 gfp_mask |= GFP_DMA; 1916 1917 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) 1918 gfp_mask |= __GFP_ZERO; 1919 1920 order = get_order(num); 1921 retry: 1922 ret_sz = 1 << (PAGE_SHIFT + order); 1923 1924 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems; 1925 k++, rem_sz -= ret_sz) { 1926 1927 num = (rem_sz > scatter_elem_sz_prev) ? 1928 scatter_elem_sz_prev : rem_sz; 1929 1930 schp->pages[k] = alloc_pages(gfp_mask | __GFP_ZERO, order); 1931 if (!schp->pages[k]) 1932 goto out; 1933 1934 if (num == scatter_elem_sz_prev) { 1935 if (unlikely(ret_sz > scatter_elem_sz_prev)) { 1936 scatter_elem_sz = ret_sz; 1937 scatter_elem_sz_prev = ret_sz; 1938 } 1939 } 1940 1941 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp, 1942 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n", 1943 k, num, ret_sz)); 1944 } /* end of for loop */ 1945 1946 schp->page_order = order; 1947 schp->k_use_sg = k; 1948 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp, 1949 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n", 1950 k, rem_sz)); 1951 1952 schp->bufflen = blk_size; 1953 if (rem_sz > 0) /* must have failed */ 1954 return -ENOMEM; 1955 return 0; 1956 out: 1957 for (i = 0; i < k; i++) 1958 __free_pages(schp->pages[i], order); 1959 1960 if (--order >= 0) 1961 goto retry; 1962 1963 return -ENOMEM; 1964 } 1965 1966 static void 1967 sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp) 1968 { 1969 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 1970 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg)); 1971 if (schp->pages && schp->sglist_len > 0) { 1972 if (!schp->dio_in_use) { 1973 int k; 1974 1975 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) { 1976 SCSI_LOG_TIMEOUT(5, 1977 sg_printk(KERN_INFO, sfp->parentdp, 1978 "sg_remove_scat: k=%d, pg=0x%p\n", 1979 k, schp->pages[k])); 1980 __free_pages(schp->pages[k], schp->page_order); 1981 } 1982 1983 kfree(schp->pages); 1984 } 1985 } 1986 memset(schp, 0, sizeof (*schp)); 1987 } 1988 1989 static int 1990 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer) 1991 { 1992 Sg_scatter_hold *schp = &srp->data; 1993 int k, num; 1994 1995 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp, 1996 "sg_read_oxfer: num_read_xfer=%d\n", 1997 num_read_xfer)); 1998 if ((!outp) || (num_read_xfer <= 0)) 1999 return 0; 2000 2001 num = 1 << (PAGE_SHIFT + schp->page_order); 2002 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) { 2003 if (num > num_read_xfer) { 2004 if (__copy_to_user(outp, page_address(schp->pages[k]), 2005 num_read_xfer)) 2006 return -EFAULT; 2007 break; 2008 } else { 2009 if (__copy_to_user(outp, page_address(schp->pages[k]), 2010 num)) 2011 return -EFAULT; 2012 num_read_xfer -= num; 2013 if (num_read_xfer <= 0) 2014 break; 2015 outp += num; 2016 } 2017 } 2018 2019 return 0; 2020 } 2021 2022 static void 2023 sg_build_reserve(Sg_fd * sfp, int req_size) 2024 { 2025 Sg_scatter_hold *schp = &sfp->reserve; 2026 2027 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 2028 "sg_build_reserve: req_size=%d\n", req_size)); 2029 do { 2030 if (req_size < PAGE_SIZE) 2031 req_size = PAGE_SIZE; 2032 if (0 == sg_build_indirect(schp, sfp, req_size)) 2033 return; 2034 else 2035 sg_remove_scat(sfp, schp); 2036 req_size >>= 1; /* divide by 2 */ 2037 } while (req_size > (PAGE_SIZE / 2)); 2038 } 2039 2040 static void 2041 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size) 2042 { 2043 Sg_scatter_hold *req_schp = &srp->data; 2044 Sg_scatter_hold *rsv_schp = &sfp->reserve; 2045 int k, num, rem; 2046 2047 srp->res_used = 1; 2048 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, 2049 "sg_link_reserve: size=%d\n", size)); 2050 rem = size; 2051 2052 num = 1 << (PAGE_SHIFT + rsv_schp->page_order); 2053 for (k = 0; k < rsv_schp->k_use_sg; k++) { 2054 if (rem <= num) { 2055 req_schp->k_use_sg = k + 1; 2056 req_schp->sglist_len = rsv_schp->sglist_len; 2057 req_schp->pages = rsv_schp->pages; 2058 2059 req_schp->bufflen = size; 2060 req_schp->page_order = rsv_schp->page_order; 2061 break; 2062 } else 2063 rem -= num; 2064 } 2065 2066 if (k >= rsv_schp->k_use_sg) 2067 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp, 2068 "sg_link_reserve: BAD size\n")); 2069 } 2070 2071 static void 2072 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp) 2073 { 2074 Sg_scatter_hold *req_schp = &srp->data; 2075 2076 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp, 2077 "sg_unlink_reserve: req->k_use_sg=%d\n", 2078 (int) req_schp->k_use_sg)); 2079 req_schp->k_use_sg = 0; 2080 req_schp->bufflen = 0; 2081 req_schp->pages = NULL; 2082 req_schp->page_order = 0; 2083 req_schp->sglist_len = 0; 2084 srp->res_used = 0; 2085 /* Called without mutex lock to avoid deadlock */ 2086 sfp->res_in_use = 0; 2087 } 2088 2089 static Sg_request * 2090 sg_get_rq_mark(Sg_fd * sfp, int pack_id) 2091 { 2092 Sg_request *resp; 2093 unsigned long iflags; 2094 2095 write_lock_irqsave(&sfp->rq_list_lock, iflags); 2096 list_for_each_entry(resp, &sfp->rq_list, entry) { 2097 /* look for requests that are ready + not SG_IO owned */ 2098 if ((1 == resp->done) && (!resp->sg_io_owned) && 2099 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) { 2100 resp->done = 2; /* guard against other readers */ 2101 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2102 return resp; 2103 } 2104 } 2105 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2106 return NULL; 2107 } 2108 2109 /* always adds to end of list */ 2110 static Sg_request * 2111 sg_add_request(Sg_fd * sfp) 2112 { 2113 int k; 2114 unsigned long iflags; 2115 Sg_request *rp = sfp->req_arr; 2116 2117 write_lock_irqsave(&sfp->rq_list_lock, iflags); 2118 if (!list_empty(&sfp->rq_list)) { 2119 if (!sfp->cmd_q) 2120 goto out_unlock; 2121 2122 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) { 2123 if (!rp->parentfp) 2124 break; 2125 } 2126 if (k >= SG_MAX_QUEUE) 2127 goto out_unlock; 2128 } 2129 memset(rp, 0, sizeof (Sg_request)); 2130 rp->parentfp = sfp; 2131 rp->header.duration = jiffies_to_msecs(jiffies); 2132 list_add_tail(&rp->entry, &sfp->rq_list); 2133 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2134 return rp; 2135 out_unlock: 2136 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2137 return NULL; 2138 } 2139 2140 /* Return of 1 for found; 0 for not found */ 2141 static int 2142 sg_remove_request(Sg_fd * sfp, Sg_request * srp) 2143 { 2144 unsigned long iflags; 2145 int res = 0; 2146 2147 if (!sfp || !srp || list_empty(&sfp->rq_list)) 2148 return res; 2149 write_lock_irqsave(&sfp->rq_list_lock, iflags); 2150 if (!list_empty(&srp->entry)) { 2151 list_del(&srp->entry); 2152 srp->parentfp = NULL; 2153 res = 1; 2154 } 2155 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2156 return res; 2157 } 2158 2159 static Sg_fd * 2160 sg_add_sfp(Sg_device * sdp) 2161 { 2162 Sg_fd *sfp; 2163 unsigned long iflags; 2164 int bufflen; 2165 2166 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN); 2167 if (!sfp) 2168 return ERR_PTR(-ENOMEM); 2169 2170 init_waitqueue_head(&sfp->read_wait); 2171 rwlock_init(&sfp->rq_list_lock); 2172 INIT_LIST_HEAD(&sfp->rq_list); 2173 kref_init(&sfp->f_ref); 2174 mutex_init(&sfp->f_mutex); 2175 sfp->timeout = SG_DEFAULT_TIMEOUT; 2176 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER; 2177 sfp->force_packid = SG_DEF_FORCE_PACK_ID; 2178 sfp->cmd_q = SG_DEF_COMMAND_Q; 2179 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN; 2180 sfp->parentdp = sdp; 2181 write_lock_irqsave(&sdp->sfd_lock, iflags); 2182 if (atomic_read(&sdp->detaching)) { 2183 write_unlock_irqrestore(&sdp->sfd_lock, iflags); 2184 kfree(sfp); 2185 return ERR_PTR(-ENODEV); 2186 } 2187 list_add_tail(&sfp->sfd_siblings, &sdp->sfds); 2188 write_unlock_irqrestore(&sdp->sfd_lock, iflags); 2189 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 2190 "sg_add_sfp: sfp=0x%p\n", sfp)); 2191 if (unlikely(sg_big_buff != def_reserved_size)) 2192 sg_big_buff = def_reserved_size; 2193 2194 bufflen = min_t(int, sg_big_buff, 2195 max_sectors_bytes(sdp->device->request_queue)); 2196 sg_build_reserve(sfp, bufflen); 2197 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, 2198 "sg_add_sfp: bufflen=%d, k_use_sg=%d\n", 2199 sfp->reserve.bufflen, 2200 sfp->reserve.k_use_sg)); 2201 2202 kref_get(&sdp->d_ref); 2203 __module_get(THIS_MODULE); 2204 return sfp; 2205 } 2206 2207 static void 2208 sg_remove_sfp_usercontext(struct work_struct *work) 2209 { 2210 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work); 2211 struct sg_device *sdp = sfp->parentdp; 2212 Sg_request *srp; 2213 unsigned long iflags; 2214 2215 /* Cleanup any responses which were never read(). */ 2216 write_lock_irqsave(&sfp->rq_list_lock, iflags); 2217 while (!list_empty(&sfp->rq_list)) { 2218 srp = list_first_entry(&sfp->rq_list, Sg_request, entry); 2219 sg_finish_rem_req(srp); 2220 list_del(&srp->entry); 2221 srp->parentfp = NULL; 2222 } 2223 write_unlock_irqrestore(&sfp->rq_list_lock, iflags); 2224 2225 if (sfp->reserve.bufflen > 0) { 2226 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp, 2227 "sg_remove_sfp: bufflen=%d, k_use_sg=%d\n", 2228 (int) sfp->reserve.bufflen, 2229 (int) sfp->reserve.k_use_sg)); 2230 sg_remove_scat(sfp, &sfp->reserve); 2231 } 2232 2233 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp, 2234 "sg_remove_sfp: sfp=0x%p\n", sfp)); 2235 kfree(sfp); 2236 2237 scsi_device_put(sdp->device); 2238 kref_put(&sdp->d_ref, sg_device_destroy); 2239 module_put(THIS_MODULE); 2240 } 2241 2242 static void 2243 sg_remove_sfp(struct kref *kref) 2244 { 2245 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref); 2246 struct sg_device *sdp = sfp->parentdp; 2247 unsigned long iflags; 2248 2249 write_lock_irqsave(&sdp->sfd_lock, iflags); 2250 list_del(&sfp->sfd_siblings); 2251 write_unlock_irqrestore(&sdp->sfd_lock, iflags); 2252 2253 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext); 2254 schedule_work(&sfp->ew.work); 2255 } 2256 2257 #ifdef CONFIG_SCSI_PROC_FS 2258 static int 2259 sg_idr_max_id(int id, void *p, void *data) 2260 { 2261 int *k = data; 2262 2263 if (*k < id) 2264 *k = id; 2265 2266 return 0; 2267 } 2268 2269 static int 2270 sg_last_dev(void) 2271 { 2272 int k = -1; 2273 unsigned long iflags; 2274 2275 read_lock_irqsave(&sg_index_lock, iflags); 2276 idr_for_each(&sg_index_idr, sg_idr_max_id, &k); 2277 read_unlock_irqrestore(&sg_index_lock, iflags); 2278 return k + 1; /* origin 1 */ 2279 } 2280 #endif 2281 2282 /* must be called with sg_index_lock held */ 2283 static Sg_device *sg_lookup_dev(int dev) 2284 { 2285 return idr_find(&sg_index_idr, dev); 2286 } 2287 2288 static Sg_device * 2289 sg_get_dev(int dev) 2290 { 2291 struct sg_device *sdp; 2292 unsigned long flags; 2293 2294 read_lock_irqsave(&sg_index_lock, flags); 2295 sdp = sg_lookup_dev(dev); 2296 if (!sdp) 2297 sdp = ERR_PTR(-ENXIO); 2298 else if (atomic_read(&sdp->detaching)) { 2299 /* If sdp->detaching, then the refcount may already be 0, in 2300 * which case it would be a bug to do kref_get(). 2301 */ 2302 sdp = ERR_PTR(-ENODEV); 2303 } else 2304 kref_get(&sdp->d_ref); 2305 read_unlock_irqrestore(&sg_index_lock, flags); 2306 2307 return sdp; 2308 } 2309 2310 #ifdef CONFIG_SCSI_PROC_FS 2311 static int sg_proc_seq_show_int(struct seq_file *s, void *v); 2312 2313 static int sg_proc_single_open_adio(struct inode *inode, struct file *file); 2314 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer, 2315 size_t count, loff_t *off); 2316 static const struct file_operations adio_fops = { 2317 .owner = THIS_MODULE, 2318 .open = sg_proc_single_open_adio, 2319 .read = seq_read, 2320 .llseek = seq_lseek, 2321 .write = sg_proc_write_adio, 2322 .release = single_release, 2323 }; 2324 2325 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file); 2326 static ssize_t sg_proc_write_dressz(struct file *filp, 2327 const char __user *buffer, size_t count, loff_t *off); 2328 static const struct file_operations dressz_fops = { 2329 .owner = THIS_MODULE, 2330 .open = sg_proc_single_open_dressz, 2331 .read = seq_read, 2332 .llseek = seq_lseek, 2333 .write = sg_proc_write_dressz, 2334 .release = single_release, 2335 }; 2336 2337 static int sg_proc_seq_show_version(struct seq_file *s, void *v); 2338 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v); 2339 static int sg_proc_seq_show_dev(struct seq_file *s, void *v); 2340 static void * dev_seq_start(struct seq_file *s, loff_t *pos); 2341 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos); 2342 static void dev_seq_stop(struct seq_file *s, void *v); 2343 static const struct seq_operations dev_seq_ops = { 2344 .start = dev_seq_start, 2345 .next = dev_seq_next, 2346 .stop = dev_seq_stop, 2347 .show = sg_proc_seq_show_dev, 2348 }; 2349 2350 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v); 2351 static const struct seq_operations devstrs_seq_ops = { 2352 .start = dev_seq_start, 2353 .next = dev_seq_next, 2354 .stop = dev_seq_stop, 2355 .show = sg_proc_seq_show_devstrs, 2356 }; 2357 2358 static int sg_proc_seq_show_debug(struct seq_file *s, void *v); 2359 static const struct seq_operations debug_seq_ops = { 2360 .start = dev_seq_start, 2361 .next = dev_seq_next, 2362 .stop = dev_seq_stop, 2363 .show = sg_proc_seq_show_debug, 2364 }; 2365 2366 static int 2367 sg_proc_init(void) 2368 { 2369 struct proc_dir_entry *p; 2370 2371 p = proc_mkdir("scsi/sg", NULL); 2372 if (!p) 2373 return 1; 2374 2375 proc_create("allow_dio", S_IRUGO | S_IWUSR, p, &adio_fops); 2376 proc_create_seq("debug", S_IRUGO, p, &debug_seq_ops); 2377 proc_create("def_reserved_size", S_IRUGO | S_IWUSR, p, &dressz_fops); 2378 proc_create_single("device_hdr", S_IRUGO, p, sg_proc_seq_show_devhdr); 2379 proc_create_seq("devices", S_IRUGO, p, &dev_seq_ops); 2380 proc_create_seq("device_strs", S_IRUGO, p, &devstrs_seq_ops); 2381 proc_create_single("version", S_IRUGO, p, sg_proc_seq_show_version); 2382 return 0; 2383 } 2384 2385 2386 static int sg_proc_seq_show_int(struct seq_file *s, void *v) 2387 { 2388 seq_printf(s, "%d\n", *((int *)s->private)); 2389 return 0; 2390 } 2391 2392 static int sg_proc_single_open_adio(struct inode *inode, struct file *file) 2393 { 2394 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio); 2395 } 2396 2397 static ssize_t 2398 sg_proc_write_adio(struct file *filp, const char __user *buffer, 2399 size_t count, loff_t *off) 2400 { 2401 int err; 2402 unsigned long num; 2403 2404 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) 2405 return -EACCES; 2406 err = kstrtoul_from_user(buffer, count, 0, &num); 2407 if (err) 2408 return err; 2409 sg_allow_dio = num ? 1 : 0; 2410 return count; 2411 } 2412 2413 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file) 2414 { 2415 return single_open(file, sg_proc_seq_show_int, &sg_big_buff); 2416 } 2417 2418 static ssize_t 2419 sg_proc_write_dressz(struct file *filp, const char __user *buffer, 2420 size_t count, loff_t *off) 2421 { 2422 int err; 2423 unsigned long k = ULONG_MAX; 2424 2425 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) 2426 return -EACCES; 2427 2428 err = kstrtoul_from_user(buffer, count, 0, &k); 2429 if (err) 2430 return err; 2431 if (k <= 1048576) { /* limit "big buff" to 1 MB */ 2432 sg_big_buff = k; 2433 return count; 2434 } 2435 return -ERANGE; 2436 } 2437 2438 static int sg_proc_seq_show_version(struct seq_file *s, void *v) 2439 { 2440 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR, 2441 sg_version_date); 2442 return 0; 2443 } 2444 2445 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v) 2446 { 2447 seq_puts(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n"); 2448 return 0; 2449 } 2450 2451 struct sg_proc_deviter { 2452 loff_t index; 2453 size_t max; 2454 }; 2455 2456 static void * dev_seq_start(struct seq_file *s, loff_t *pos) 2457 { 2458 struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL); 2459 2460 s->private = it; 2461 if (! it) 2462 return NULL; 2463 2464 it->index = *pos; 2465 it->max = sg_last_dev(); 2466 if (it->index >= it->max) 2467 return NULL; 2468 return it; 2469 } 2470 2471 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos) 2472 { 2473 struct sg_proc_deviter * it = s->private; 2474 2475 *pos = ++it->index; 2476 return (it->index < it->max) ? it : NULL; 2477 } 2478 2479 static void dev_seq_stop(struct seq_file *s, void *v) 2480 { 2481 kfree(s->private); 2482 } 2483 2484 static int sg_proc_seq_show_dev(struct seq_file *s, void *v) 2485 { 2486 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v; 2487 Sg_device *sdp; 2488 struct scsi_device *scsidp; 2489 unsigned long iflags; 2490 2491 read_lock_irqsave(&sg_index_lock, iflags); 2492 sdp = it ? sg_lookup_dev(it->index) : NULL; 2493 if ((NULL == sdp) || (NULL == sdp->device) || 2494 (atomic_read(&sdp->detaching))) 2495 seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n"); 2496 else { 2497 scsidp = sdp->device; 2498 seq_printf(s, "%d\t%d\t%d\t%llu\t%d\t%d\t%d\t%d\t%d\n", 2499 scsidp->host->host_no, scsidp->channel, 2500 scsidp->id, scsidp->lun, (int) scsidp->type, 2501 1, 2502 (int) scsidp->queue_depth, 2503 (int) atomic_read(&scsidp->device_busy), 2504 (int) scsi_device_online(scsidp)); 2505 } 2506 read_unlock_irqrestore(&sg_index_lock, iflags); 2507 return 0; 2508 } 2509 2510 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v) 2511 { 2512 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v; 2513 Sg_device *sdp; 2514 struct scsi_device *scsidp; 2515 unsigned long iflags; 2516 2517 read_lock_irqsave(&sg_index_lock, iflags); 2518 sdp = it ? sg_lookup_dev(it->index) : NULL; 2519 scsidp = sdp ? sdp->device : NULL; 2520 if (sdp && scsidp && (!atomic_read(&sdp->detaching))) 2521 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n", 2522 scsidp->vendor, scsidp->model, scsidp->rev); 2523 else 2524 seq_puts(s, "<no active device>\n"); 2525 read_unlock_irqrestore(&sg_index_lock, iflags); 2526 return 0; 2527 } 2528 2529 /* must be called while holding sg_index_lock */ 2530 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp) 2531 { 2532 int k, new_interface, blen, usg; 2533 Sg_request *srp; 2534 Sg_fd *fp; 2535 const sg_io_hdr_t *hp; 2536 const char * cp; 2537 unsigned int ms; 2538 2539 k = 0; 2540 list_for_each_entry(fp, &sdp->sfds, sfd_siblings) { 2541 k++; 2542 read_lock(&fp->rq_list_lock); /* irqs already disabled */ 2543 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d " 2544 "(res)sgat=%d low_dma=%d\n", k, 2545 jiffies_to_msecs(fp->timeout), 2546 fp->reserve.bufflen, 2547 (int) fp->reserve.k_use_sg, 2548 (int) sdp->device->host->unchecked_isa_dma); 2549 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n", 2550 (int) fp->cmd_q, (int) fp->force_packid, 2551 (int) fp->keep_orphan); 2552 list_for_each_entry(srp, &fp->rq_list, entry) { 2553 hp = &srp->header; 2554 new_interface = (hp->interface_id == '\0') ? 0 : 1; 2555 if (srp->res_used) { 2556 if (new_interface && 2557 (SG_FLAG_MMAP_IO & hp->flags)) 2558 cp = " mmap>> "; 2559 else 2560 cp = " rb>> "; 2561 } else { 2562 if (SG_INFO_DIRECT_IO_MASK & hp->info) 2563 cp = " dio>> "; 2564 else 2565 cp = " "; 2566 } 2567 seq_puts(s, cp); 2568 blen = srp->data.bufflen; 2569 usg = srp->data.k_use_sg; 2570 seq_puts(s, srp->done ? 2571 ((1 == srp->done) ? "rcv:" : "fin:") 2572 : "act:"); 2573 seq_printf(s, " id=%d blen=%d", 2574 srp->header.pack_id, blen); 2575 if (srp->done) 2576 seq_printf(s, " dur=%d", hp->duration); 2577 else { 2578 ms = jiffies_to_msecs(jiffies); 2579 seq_printf(s, " t_o/elap=%d/%d", 2580 (new_interface ? hp->timeout : 2581 jiffies_to_msecs(fp->timeout)), 2582 (ms > hp->duration ? ms - hp->duration : 0)); 2583 } 2584 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg, 2585 (int) srp->data.cmd_opcode); 2586 } 2587 if (list_empty(&fp->rq_list)) 2588 seq_puts(s, " No requests active\n"); 2589 read_unlock(&fp->rq_list_lock); 2590 } 2591 } 2592 2593 static int sg_proc_seq_show_debug(struct seq_file *s, void *v) 2594 { 2595 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v; 2596 Sg_device *sdp; 2597 unsigned long iflags; 2598 2599 if (it && (0 == it->index)) 2600 seq_printf(s, "max_active_device=%d def_reserved_size=%d\n", 2601 (int)it->max, sg_big_buff); 2602 2603 read_lock_irqsave(&sg_index_lock, iflags); 2604 sdp = it ? sg_lookup_dev(it->index) : NULL; 2605 if (NULL == sdp) 2606 goto skip; 2607 read_lock(&sdp->sfd_lock); 2608 if (!list_empty(&sdp->sfds)) { 2609 seq_printf(s, " >>> device=%s ", sdp->disk->disk_name); 2610 if (atomic_read(&sdp->detaching)) 2611 seq_puts(s, "detaching pending close "); 2612 else if (sdp->device) { 2613 struct scsi_device *scsidp = sdp->device; 2614 2615 seq_printf(s, "%d:%d:%d:%llu em=%d", 2616 scsidp->host->host_no, 2617 scsidp->channel, scsidp->id, 2618 scsidp->lun, 2619 scsidp->host->hostt->emulated); 2620 } 2621 seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n", 2622 sdp->sg_tablesize, sdp->exclude, sdp->open_cnt); 2623 sg_proc_debug_helper(s, sdp); 2624 } 2625 read_unlock(&sdp->sfd_lock); 2626 skip: 2627 read_unlock_irqrestore(&sg_index_lock, iflags); 2628 return 0; 2629 } 2630 2631 #endif /* CONFIG_SCSI_PROC_FS */ 2632 2633 module_init(init_sg); 2634 module_exit(exit_sg); 2635