Commit | Line | Data |
---|---|---|
09c434b8 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
1da177e4 LT |
2 | /* |
3 | * scsi.c Copyright (C) 1992 Drew Eckhardt | |
4 | * Copyright (C) 1993, 1994, 1995, 1999 Eric Youngdale | |
5 | * Copyright (C) 2002, 2003 Christoph Hellwig | |
6 | * | |
7 | * generic mid-level SCSI driver | |
8 | * Initial versions: Drew Eckhardt | |
9 | * Subsequent revisions: Eric Youngdale | |
10 | * | |
11 | * <drew@colorado.edu> | |
12 | * | |
13 | * Bug correction thanks go to : | |
14 | * Rik Faith <faith@cs.unc.edu> | |
15 | * Tommy Thorn <tthorn> | |
16 | * Thomas Wuensche <tw@fgb1.fgb.mw.tu-muenchen.de> | |
17 | * | |
18 | * Modified by Eric Youngdale eric@andante.org or ericy@gnu.ai.mit.edu to | |
19 | * add scatter-gather, multiple outstanding request, and other | |
20 | * enhancements. | |
21 | * | |
22 | * Native multichannel, wide scsi, /proc/scsi and hot plugging | |
23 | * support added by Michael Neuffer <mike@i-connect.net> | |
24 | * | |
25 | * Added request_module("scsi_hostadapter") for kerneld: | |
26 | * (Put an "alias scsi_hostadapter your_hostadapter" in /etc/modprobe.conf) | |
27 | * Bjorn Ekwall <bj0rn@blox.se> | |
28 | * (changed to kmod) | |
29 | * | |
30 | * Major improvements to the timeout, abort, and reset processing, | |
31 | * as well as performance modifications for large queue depths by | |
32 | * Leonard N. Zubkoff <lnz@dandelion.com> | |
33 | * | |
34 | * Converted cli() code to spinlocks, Ingo Molnar | |
35 | * | |
36 | * Jiffies wrap fixes (host->resetting), 3 Dec 1998 Andrea Arcangeli | |
37 | * | |
38 | * out_of_space hacks, D. Gilbert (dpg) 990608 | |
39 | */ | |
40 | ||
41 | #include <linux/module.h> | |
42 | #include <linux/moduleparam.h> | |
43 | #include <linux/kernel.h> | |
1da177e4 LT |
44 | #include <linux/timer.h> |
45 | #include <linux/string.h> | |
46 | #include <linux/slab.h> | |
47 | #include <linux/blkdev.h> | |
48 | #include <linux/delay.h> | |
49 | #include <linux/init.h> | |
50 | #include <linux/completion.h> | |
1da177e4 LT |
51 | #include <linux/unistd.h> |
52 | #include <linux/spinlock.h> | |
53 | #include <linux/kmod.h> | |
54 | #include <linux/interrupt.h> | |
55 | #include <linux/notifier.h> | |
56 | #include <linux/cpu.h> | |
0b950672 | 57 | #include <linux/mutex.h> |
3c6bdaea | 58 | #include <asm/unaligned.h> |
1da177e4 LT |
59 | |
60 | #include <scsi/scsi.h> | |
61 | #include <scsi/scsi_cmnd.h> | |
62 | #include <scsi/scsi_dbg.h> | |
63 | #include <scsi/scsi_device.h> | |
7b3d9545 | 64 | #include <scsi/scsi_driver.h> |
1da177e4 LT |
65 | #include <scsi/scsi_eh.h> |
66 | #include <scsi/scsi_host.h> | |
67 | #include <scsi/scsi_tcq.h> | |
1da177e4 LT |
68 | |
69 | #include "scsi_priv.h" | |
70 | #include "scsi_logging.h" | |
71 | ||
bf816235 KT |
72 | #define CREATE_TRACE_POINTS |
73 | #include <trace/events/scsi.h> | |
74 | ||
1da177e4 LT |
75 | /* |
76 | * Definitions and constants. | |
77 | */ | |
78 | ||
1da177e4 LT |
79 | /* |
80 | * Note - the initial logging level can be set here to log events at boot time. | |
81 | * After the system is up, you may enable logging via the /proc interface. | |
82 | */ | |
83 | unsigned int scsi_logging_level; | |
84 | #if defined(CONFIG_SCSI_LOGGING) | |
85 | EXPORT_SYMBOL(scsi_logging_level); | |
86 | #endif | |
87 | ||
1da177e4 LT |
88 | #ifdef CONFIG_SCSI_LOGGING |
89 | void scsi_log_send(struct scsi_cmnd *cmd) | |
90 | { | |
91 | unsigned int level; | |
1da177e4 LT |
92 | |
93 | /* | |
94 | * If ML QUEUE log level is greater than or equal to: | |
95 | * | |
96 | * 1: nothing (match completion) | |
97 | * | |
c11c004b | 98 | * 2: log opcode + command of all commands + cmd address |
1da177e4 | 99 | * |
c11c004b | 100 | * 3: same as 2 |
1da177e4 | 101 | * |
a4a6afb4 | 102 | * 4: same as 3 |
1da177e4 LT |
103 | */ |
104 | if (unlikely(scsi_logging_level)) { | |
105 | level = SCSI_LOG_LEVEL(SCSI_LOG_MLQUEUE_SHIFT, | |
106 | SCSI_LOG_MLQUEUE_BITS); | |
107 | if (level > 1) { | |
c11c004b HR |
108 | scmd_printk(KERN_INFO, cmd, |
109 | "Send: scmd 0x%p\n", cmd); | |
1da177e4 | 110 | scsi_print_command(cmd); |
1da177e4 LT |
111 | } |
112 | } | |
113 | } | |
114 | ||
115 | void scsi_log_completion(struct scsi_cmnd *cmd, int disposition) | |
116 | { | |
117 | unsigned int level; | |
1da177e4 LT |
118 | |
119 | /* | |
120 | * If ML COMPLETE log level is greater than or equal to: | |
121 | * | |
122 | * 1: log disposition, result, opcode + command, and conditionally | |
123 | * sense data for failures or non SUCCESS dispositions. | |
124 | * | |
125 | * 2: same as 1 but for all command completions. | |
126 | * | |
c11c004b | 127 | * 3: same as 2 |
1da177e4 LT |
128 | * |
129 | * 4: same as 3 plus dump extra junk | |
130 | */ | |
131 | if (unlikely(scsi_logging_level)) { | |
132 | level = SCSI_LOG_LEVEL(SCSI_LOG_MLCOMPLETE_SHIFT, | |
133 | SCSI_LOG_MLCOMPLETE_BITS); | |
134 | if (((level > 0) && (cmd->result || disposition != SUCCESS)) || | |
135 | (level > 1)) { | |
026f8da8 | 136 | scsi_print_result(cmd, "Done", disposition); |
1da177e4 | 137 | scsi_print_command(cmd); |
d0672a03 | 138 | if (scsi_status_is_check_condition(cmd->result)) |
d811b848 | 139 | scsi_print_sense(cmd); |
a4d04a4c MP |
140 | if (level > 3) |
141 | scmd_printk(KERN_INFO, cmd, | |
142 | "scsi host busy %d failed %d\n", | |
c84b023a | 143 | scsi_host_busy(cmd->device->host), |
a4d04a4c | 144 | cmd->device->host->host_failed); |
1da177e4 LT |
145 | } |
146 | } | |
147 | } | |
148 | #endif | |
149 | ||
eb44820c RL |
150 | /** |
151 | * scsi_finish_command - cleanup and pass command back to upper layer | |
152 | * @cmd: the command | |
1da177e4 | 153 | * |
eb44820c | 154 | * Description: Pass command off to upper layer for finishing of I/O |
1da177e4 LT |
155 | * request, waking processes that are waiting on results, |
156 | * etc. | |
157 | */ | |
158 | void scsi_finish_command(struct scsi_cmnd *cmd) | |
159 | { | |
160 | struct scsi_device *sdev = cmd->device; | |
f0c0a376 | 161 | struct scsi_target *starget = scsi_target(sdev); |
1da177e4 | 162 | struct Scsi_Host *shost = sdev->host; |
7b3d9545 LT |
163 | struct scsi_driver *drv; |
164 | unsigned int good_bytes; | |
1da177e4 | 165 | |
6eb045e0 | 166 | scsi_device_unbusy(sdev, cmd); |
1da177e4 | 167 | |
cd9070c9 CH |
168 | /* |
169 | * Clear the flags that say that the device/target/host is no longer | |
170 | * capable of accepting new commands. | |
171 | */ | |
172 | if (atomic_read(&shost->host_blocked)) | |
173 | atomic_set(&shost->host_blocked, 0); | |
174 | if (atomic_read(&starget->target_blocked)) | |
175 | atomic_set(&starget->target_blocked, 0); | |
176 | if (atomic_read(&sdev->device_blocked)) | |
177 | atomic_set(&sdev->device_blocked, 0); | |
1da177e4 | 178 | |
3bf743e7 JG |
179 | SCSI_LOG_MLCOMPLETE(4, sdev_printk(KERN_INFO, sdev, |
180 | "Notifying upper driver of completion " | |
181 | "(result %x)\n", cmd->result)); | |
1da177e4 | 182 | |
f18573ab | 183 | good_bytes = scsi_bufflen(cmd); |
aa8e25e5 | 184 | if (!blk_rq_is_passthrough(scsi_cmd_to_rq(cmd))) { |
427e59f0 | 185 | int old_good_bytes = good_bytes; |
7b3d9545 LT |
186 | drv = scsi_cmd_to_driver(cmd); |
187 | if (drv->done) | |
188 | good_bytes = drv->done(cmd); | |
427e59f0 JB |
189 | /* |
190 | * USB may not give sense identifying bad sector and | |
191 | * simply return a residue instead, so subtract off the | |
192 | * residue if drv->done() error processing indicates no | |
193 | * change to the completion length. | |
194 | */ | |
195 | if (good_bytes == old_good_bytes) | |
196 | good_bytes -= scsi_get_resid(cmd); | |
7b3d9545 LT |
197 | } |
198 | scsi_io_completion(cmd, good_bytes); | |
1da177e4 | 199 | } |
1da177e4 | 200 | |
ca445321 ML |
201 | |
202 | /* | |
4bc3bffc | 203 | * 1024 is big enough for saturating fast SCSI LUNs. |
ca445321 | 204 | */ |
020b0f0a | 205 | int scsi_device_max_queue_depth(struct scsi_device *sdev) |
ca445321 | 206 | { |
4bc3bffc | 207 | return min_t(int, sdev->host->can_queue, 1024); |
ca445321 ML |
208 | } |
209 | ||
eb44820c | 210 | /** |
db5ed4df | 211 | * scsi_change_queue_depth - change a device's queue depth |
eb44820c | 212 | * @sdev: SCSI Device in question |
db5ed4df | 213 | * @depth: number of commands allowed to be queued to the driver |
1da177e4 | 214 | * |
db5ed4df | 215 | * Sets the device queue depth and returns the new value. |
1da177e4 | 216 | */ |
db5ed4df | 217 | int scsi_change_queue_depth(struct scsi_device *sdev, int depth) |
1da177e4 | 218 | { |
ca445321 ML |
219 | depth = min_t(int, depth, scsi_device_max_queue_depth(sdev)); |
220 | ||
64d513ac CH |
221 | if (depth > 0) { |
222 | sdev->queue_depth = depth; | |
223 | wmb(); | |
885ace9e | 224 | } |
1da177e4 | 225 | |
d278d4a8 JA |
226 | if (sdev->request_queue) |
227 | blk_set_queue_depth(sdev->request_queue, depth); | |
228 | ||
020b0f0a ML |
229 | sbitmap_resize(&sdev->budget_map, sdev->queue_depth); |
230 | ||
db5ed4df | 231 | return sdev->queue_depth; |
1da177e4 | 232 | } |
db5ed4df | 233 | EXPORT_SYMBOL(scsi_change_queue_depth); |
1da177e4 | 234 | |
eb44820c RL |
235 | /** |
236 | * scsi_track_queue_full - track QUEUE_FULL events to adjust queue depth | |
237 | * @sdev: SCSI Device in question | |
238 | * @depth: Current number of outstanding SCSI commands on this device, | |
239 | * not counting the one returned as QUEUE_FULL. | |
1da177e4 | 240 | * |
eb44820c | 241 | * Description: This function will track successive QUEUE_FULL events on a |
1da177e4 LT |
242 | * specific SCSI device to determine if and when there is a |
243 | * need to adjust the queue depth on the device. | |
244 | * | |
eb44820c | 245 | * Returns: 0 - No change needed, >0 - Adjust queue depth to this new depth, |
1da177e4 LT |
246 | * -1 - Drop back to untagged operation using host->cmd_per_lun |
247 | * as the untagged command depth | |
248 | * | |
249 | * Lock Status: None held on entry | |
250 | * | |
251 | * Notes: Low level drivers may call this at any time and we will do | |
252 | * "The Right Thing." We are interrupt context safe. | |
253 | */ | |
254 | int scsi_track_queue_full(struct scsi_device *sdev, int depth) | |
255 | { | |
4a84067d VD |
256 | |
257 | /* | |
258 | * Don't let QUEUE_FULLs on the same | |
259 | * jiffies count, they could all be from | |
260 | * same event. | |
261 | */ | |
262 | if ((jiffies >> 4) == (sdev->last_queue_full_time >> 4)) | |
1da177e4 LT |
263 | return 0; |
264 | ||
4a84067d | 265 | sdev->last_queue_full_time = jiffies; |
1da177e4 LT |
266 | if (sdev->last_queue_full_depth != depth) { |
267 | sdev->last_queue_full_count = 1; | |
268 | sdev->last_queue_full_depth = depth; | |
269 | } else { | |
270 | sdev->last_queue_full_count++; | |
271 | } | |
272 | ||
273 | if (sdev->last_queue_full_count <= 10) | |
274 | return 0; | |
609aa22f | 275 | |
db5ed4df | 276 | return scsi_change_queue_depth(sdev, depth); |
1da177e4 LT |
277 | } |
278 | EXPORT_SYMBOL(scsi_track_queue_full); | |
279 | ||
881a256d MW |
280 | /** |
281 | * scsi_vpd_inquiry - Request a device provide us with a VPD page | |
282 | * @sdev: The device to ask | |
283 | * @buffer: Where to put the result | |
284 | * @page: Which Vital Product Data to return | |
285 | * @len: The length of the buffer | |
286 | * | |
287 | * This is an internal helper function. You probably want to use | |
288 | * scsi_get_vpd_page instead. | |
289 | * | |
bc8945df | 290 | * Returns size of the vpd page on success or a negative error number. |
881a256d MW |
291 | */ |
292 | static int scsi_vpd_inquiry(struct scsi_device *sdev, unsigned char *buffer, | |
293 | u8 page, unsigned len) | |
294 | { | |
295 | int result; | |
296 | unsigned char cmd[16]; | |
297 | ||
bc8945df HR |
298 | if (len < 4) |
299 | return -EINVAL; | |
300 | ||
881a256d MW |
301 | cmd[0] = INQUIRY; |
302 | cmd[1] = 1; /* EVPD */ | |
303 | cmd[2] = page; | |
304 | cmd[3] = len >> 8; | |
305 | cmd[4] = len & 0xff; | |
306 | cmd[5] = 0; /* Control byte */ | |
307 | ||
308 | /* | |
309 | * I'm not convinced we need to try quite this hard to get VPD, but | |
310 | * all the existing users tried this hard. | |
311 | */ | |
312 | result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buffer, | |
95a3639e | 313 | len, NULL, 30 * HZ, 3, NULL); |
881a256d | 314 | if (result) |
bc8945df | 315 | return -EIO; |
881a256d MW |
316 | |
317 | /* Sanity check that we got the page back that we asked for */ | |
318 | if (buffer[1] != page) | |
319 | return -EIO; | |
320 | ||
bc8945df | 321 | return get_unaligned_be16(&buffer[2]) + 4; |
881a256d MW |
322 | } |
323 | ||
324 | /** | |
325 | * scsi_get_vpd_page - Get Vital Product Data from a SCSI device | |
326 | * @sdev: The device to ask | |
327 | * @page: Which Vital Product Data to return | |
786f8ba2 RD |
328 | * @buf: where to store the VPD |
329 | * @buf_len: number of bytes in the VPD buffer area | |
881a256d MW |
330 | * |
331 | * SCSI devices may optionally supply Vital Product Data. Each 'page' | |
332 | * of VPD is defined in the appropriate SCSI document (eg SPC, SBC). | |
333 | * If the device supports this VPD page, this routine returns a pointer | |
334 | * to a buffer containing the data from that page. The caller is | |
335 | * responsible for calling kfree() on this pointer when it is no longer | |
336 | * needed. If we cannot retrieve the VPD page this routine returns %NULL. | |
337 | */ | |
e3deec09 JB |
338 | int scsi_get_vpd_page(struct scsi_device *sdev, u8 page, unsigned char *buf, |
339 | int buf_len) | |
881a256d MW |
340 | { |
341 | int i, result; | |
881a256d | 342 | |
7562523e MP |
343 | if (sdev->skip_vpd_pages) |
344 | goto fail; | |
345 | ||
881a256d | 346 | /* Ask for all the pages supported by this device */ |
e3deec09 | 347 | result = scsi_vpd_inquiry(sdev, buf, 0, buf_len); |
bc8945df | 348 | if (result < 4) |
881a256d MW |
349 | goto fail; |
350 | ||
351 | /* If the user actually wanted this page, we can skip the rest */ | |
352 | if (page == 0) | |
16d3ea26 | 353 | return 0; |
881a256d | 354 | |
bc8945df HR |
355 | for (i = 4; i < min(result, buf_len); i++) |
356 | if (buf[i] == page) | |
881a256d | 357 | goto found; |
e3deec09 | 358 | |
bc8945df | 359 | if (i < result && i >= buf_len) |
e3deec09 JB |
360 | /* ran off the end of the buffer, give us benefit of doubt */ |
361 | goto found; | |
881a256d MW |
362 | /* The device claims it doesn't support the requested page */ |
363 | goto fail; | |
364 | ||
365 | found: | |
e3deec09 | 366 | result = scsi_vpd_inquiry(sdev, buf, page, buf_len); |
bc8945df | 367 | if (result < 0) |
881a256d MW |
368 | goto fail; |
369 | ||
e3deec09 | 370 | return 0; |
881a256d MW |
371 | |
372 | fail: | |
e3deec09 | 373 | return -EINVAL; |
881a256d MW |
374 | } |
375 | EXPORT_SYMBOL_GPL(scsi_get_vpd_page); | |
376 | ||
1e3f720a BVA |
377 | /** |
378 | * scsi_get_vpd_buf - Get Vital Product Data from a SCSI device | |
379 | * @sdev: The device to ask | |
380 | * @page: Which Vital Product Data to return | |
1e3f720a BVA |
381 | * |
382 | * Returns %NULL upon failure. | |
383 | */ | |
ccf1e004 | 384 | static struct scsi_vpd *scsi_get_vpd_buf(struct scsi_device *sdev, u8 page) |
1e3f720a | 385 | { |
ccf1e004 | 386 | struct scsi_vpd *vpd_buf; |
1e3f720a BVA |
387 | int vpd_len = SCSI_VPD_PG_LEN, result; |
388 | ||
389 | retry_pg: | |
ccf1e004 | 390 | vpd_buf = kmalloc(sizeof(*vpd_buf) + vpd_len, GFP_KERNEL); |
1e3f720a BVA |
391 | if (!vpd_buf) |
392 | return NULL; | |
393 | ||
ccf1e004 | 394 | result = scsi_vpd_inquiry(sdev, vpd_buf->data, page, vpd_len); |
1e3f720a BVA |
395 | if (result < 0) { |
396 | kfree(vpd_buf); | |
397 | return NULL; | |
398 | } | |
399 | if (result > vpd_len) { | |
400 | vpd_len = result; | |
401 | kfree(vpd_buf); | |
402 | goto retry_pg; | |
403 | } | |
404 | ||
ccf1e004 | 405 | vpd_buf->len = result; |
1e3f720a BVA |
406 | |
407 | return vpd_buf; | |
408 | } | |
409 | ||
410 | static void scsi_update_vpd_page(struct scsi_device *sdev, u8 page, | |
ccf1e004 | 411 | struct scsi_vpd __rcu **sdev_vpd_buf) |
1e3f720a | 412 | { |
ccf1e004 | 413 | struct scsi_vpd *vpd_buf; |
1e3f720a | 414 | |
ccf1e004 | 415 | vpd_buf = scsi_get_vpd_buf(sdev, page); |
1e3f720a BVA |
416 | if (!vpd_buf) |
417 | return; | |
418 | ||
419 | mutex_lock(&sdev->inquiry_mutex); | |
c0eaf15c PM |
420 | vpd_buf = rcu_replace_pointer(*sdev_vpd_buf, vpd_buf, |
421 | lockdep_is_held(&sdev->inquiry_mutex)); | |
1e3f720a BVA |
422 | mutex_unlock(&sdev->inquiry_mutex); |
423 | ||
ccf1e004 BVA |
424 | if (vpd_buf) |
425 | kfree_rcu(vpd_buf, rcu); | |
1e3f720a BVA |
426 | } |
427 | ||
b3ae8780 HR |
428 | /** |
429 | * scsi_attach_vpd - Attach Vital Product Data to a SCSI device structure | |
430 | * @sdev: The device to ask | |
431 | * | |
432 | * Attach the 'Device Identification' VPD page (0x83) and the | |
433 | * 'Unit Serial Number' VPD page (0x80) to a SCSI device | |
434 | * structure. This information can be used to identify the device | |
435 | * uniquely. | |
436 | */ | |
437 | void scsi_attach_vpd(struct scsi_device *sdev) | |
438 | { | |
ccf1e004 BVA |
439 | int i; |
440 | struct scsi_vpd *vpd_buf; | |
b3ae8780 | 441 | |
5ddfe085 | 442 | if (!scsi_device_supports_vpd(sdev)) |
b3ae8780 | 443 | return; |
5ddfe085 | 444 | |
b3ae8780 | 445 | /* Ask for all the pages supported by this device */ |
ccf1e004 | 446 | vpd_buf = scsi_get_vpd_buf(sdev, 0); |
1e3f720a | 447 | if (!vpd_buf) |
b3ae8780 | 448 | return; |
b3ae8780 | 449 | |
ccf1e004 | 450 | for (i = 4; i < vpd_buf->len; i++) { |
d188b067 RA |
451 | if (vpd_buf->data[i] == 0x0) |
452 | scsi_update_vpd_page(sdev, 0x0, &sdev->vpd_pg0); | |
ccf1e004 BVA |
453 | if (vpd_buf->data[i] == 0x80) |
454 | scsi_update_vpd_page(sdev, 0x80, &sdev->vpd_pg80); | |
455 | if (vpd_buf->data[i] == 0x83) | |
456 | scsi_update_vpd_page(sdev, 0x83, &sdev->vpd_pg83); | |
d188b067 RA |
457 | if (vpd_buf->data[i] == 0x89) |
458 | scsi_update_vpd_page(sdev, 0x89, &sdev->vpd_pg89); | |
b3ae8780 HR |
459 | } |
460 | kfree(vpd_buf); | |
b3ae8780 HR |
461 | } |
462 | ||
3c6bdaea MP |
463 | /** |
464 | * scsi_report_opcode - Find out if a given command opcode is supported | |
465 | * @sdev: scsi device to query | |
466 | * @buffer: scratch buffer (must be at least 20 bytes long) | |
467 | * @len: length of buffer | |
468 | * @opcode: opcode for command to look up | |
469 | * | |
470 | * Uses the REPORT SUPPORTED OPERATION CODES to look up the given | |
66c28f97 MP |
471 | * opcode. Returns -EINVAL if RSOC fails, 0 if the command opcode is |
472 | * unsupported and 1 if the device claims to support the command. | |
3c6bdaea MP |
473 | */ |
474 | int scsi_report_opcode(struct scsi_device *sdev, unsigned char *buffer, | |
475 | unsigned int len, unsigned char opcode) | |
476 | { | |
477 | unsigned char cmd[16]; | |
478 | struct scsi_sense_hdr sshdr; | |
479 | int result; | |
480 | ||
481 | if (sdev->no_report_opcodes || sdev->scsi_level < SCSI_SPC_3) | |
66c28f97 | 482 | return -EINVAL; |
3c6bdaea MP |
483 | |
484 | memset(cmd, 0, 16); | |
485 | cmd[0] = MAINTENANCE_IN; | |
486 | cmd[1] = MI_REPORT_SUPPORTED_OPERATION_CODES; | |
487 | cmd[2] = 1; /* One command format */ | |
488 | cmd[3] = opcode; | |
489 | put_unaligned_be32(len, &cmd[6]); | |
490 | memset(buffer, 0, len); | |
491 | ||
492 | result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buffer, len, | |
493 | &sshdr, 30 * HZ, 3, NULL); | |
494 | ||
ced202f7 HR |
495 | if (result < 0) |
496 | return result; | |
3c6bdaea MP |
497 | if (result && scsi_sense_valid(&sshdr) && |
498 | sshdr.sense_key == ILLEGAL_REQUEST && | |
499 | (sshdr.asc == 0x20 || sshdr.asc == 0x24) && sshdr.ascq == 0x00) | |
66c28f97 | 500 | return -EINVAL; |
3c6bdaea MP |
501 | |
502 | if ((buffer[1] & 3) == 3) /* Command supported */ | |
503 | return 1; | |
504 | ||
505 | return 0; | |
506 | } | |
507 | EXPORT_SYMBOL(scsi_report_opcode); | |
508 | ||
1da177e4 | 509 | /** |
eb44820c | 510 | * scsi_device_get - get an additional reference to a scsi_device |
1da177e4 LT |
511 | * @sdev: device to get a reference to |
512 | * | |
eb44820c | 513 | * Description: Gets a reference to the scsi_device and increments the use count |
1da177e4 LT |
514 | * of the underlying LLDD module. You must hold host_lock of the |
515 | * parent Scsi_Host or already have a reference when calling this. | |
cff549e4 CH |
516 | * |
517 | * This will fail if a device is deleted or cancelled, or when the LLD module | |
518 | * is in the process of being unloaded. | |
1da177e4 LT |
519 | */ |
520 | int scsi_device_get(struct scsi_device *sdev) | |
521 | { | |
cff549e4 CH |
522 | if (sdev->sdev_state == SDEV_DEL || sdev->sdev_state == SDEV_CANCEL) |
523 | goto fail; | |
1da177e4 | 524 | if (!get_device(&sdev->sdev_gendev)) |
cff549e4 CH |
525 | goto fail; |
526 | if (!try_module_get(sdev->host->hostt->module)) | |
527 | goto fail_put_device; | |
1da177e4 | 528 | return 0; |
cff549e4 CH |
529 | |
530 | fail_put_device: | |
531 | put_device(&sdev->sdev_gendev); | |
532 | fail: | |
533 | return -ENXIO; | |
1da177e4 LT |
534 | } |
535 | EXPORT_SYMBOL(scsi_device_get); | |
536 | ||
537 | /** | |
538 | * scsi_device_put - release a reference to a scsi_device | |
539 | * @sdev: device to release a reference on. | |
540 | * | |
eb44820c RL |
541 | * Description: Release a reference to the scsi_device and decrements the use |
542 | * count of the underlying LLDD module. The device is freed once the last | |
1da177e4 LT |
543 | * user vanishes. |
544 | */ | |
545 | void scsi_device_put(struct scsi_device *sdev) | |
546 | { | |
f2b85040 ML |
547 | struct module *mod = sdev->host->hostt->module; |
548 | ||
1da177e4 | 549 | put_device(&sdev->sdev_gendev); |
f2b85040 | 550 | module_put(mod); |
1da177e4 LT |
551 | } |
552 | EXPORT_SYMBOL(scsi_device_put); | |
553 | ||
eb44820c | 554 | /* helper for shost_for_each_device, see that for documentation */ |
1da177e4 LT |
555 | struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *shost, |
556 | struct scsi_device *prev) | |
557 | { | |
558 | struct list_head *list = (prev ? &prev->siblings : &shost->__devices); | |
559 | struct scsi_device *next = NULL; | |
560 | unsigned long flags; | |
561 | ||
562 | spin_lock_irqsave(shost->host_lock, flags); | |
563 | while (list->next != &shost->__devices) { | |
564 | next = list_entry(list->next, struct scsi_device, siblings); | |
565 | /* skip devices that we can't get a reference to */ | |
566 | if (!scsi_device_get(next)) | |
567 | break; | |
568 | next = NULL; | |
569 | list = list->next; | |
570 | } | |
571 | spin_unlock_irqrestore(shost->host_lock, flags); | |
572 | ||
573 | if (prev) | |
574 | scsi_device_put(prev); | |
575 | return next; | |
576 | } | |
577 | EXPORT_SYMBOL(__scsi_iterate_devices); | |
578 | ||
579 | /** | |
580 | * starget_for_each_device - helper to walk all devices of a target | |
581 | * @starget: target whose devices we want to iterate over. | |
eb44820c RL |
582 | * @data: Opaque passed to each function call. |
583 | * @fn: Function to call on each device | |
1da177e4 | 584 | * |
522939d4 | 585 | * This traverses over each device of @starget. The devices have |
1da177e4 LT |
586 | * a reference that must be released by scsi_host_put when breaking |
587 | * out of the loop. | |
588 | */ | |
522939d4 | 589 | void starget_for_each_device(struct scsi_target *starget, void *data, |
1da177e4 LT |
590 | void (*fn)(struct scsi_device *, void *)) |
591 | { | |
592 | struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); | |
593 | struct scsi_device *sdev; | |
594 | ||
595 | shost_for_each_device(sdev, shost) { | |
596 | if ((sdev->channel == starget->channel) && | |
597 | (sdev->id == starget->id)) | |
598 | fn(sdev, data); | |
599 | } | |
600 | } | |
601 | EXPORT_SYMBOL(starget_for_each_device); | |
602 | ||
522939d4 | 603 | /** |
14f501a4 | 604 | * __starget_for_each_device - helper to walk all devices of a target (UNLOCKED) |
522939d4 | 605 | * @starget: target whose devices we want to iterate over. |
14f501a4 RD |
606 | * @data: parameter for callback @fn() |
607 | * @fn: callback function that is invoked for each device | |
522939d4 MR |
608 | * |
609 | * This traverses over each device of @starget. It does _not_ | |
610 | * take a reference on the scsi_device, so the whole loop must be | |
611 | * protected by shost->host_lock. | |
612 | * | |
613 | * Note: The only reason why drivers would want to use this is because | |
614 | * they need to access the device list in irq context. Otherwise you | |
615 | * really want to use starget_for_each_device instead. | |
616 | **/ | |
617 | void __starget_for_each_device(struct scsi_target *starget, void *data, | |
618 | void (*fn)(struct scsi_device *, void *)) | |
619 | { | |
620 | struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); | |
621 | struct scsi_device *sdev; | |
622 | ||
623 | __shost_for_each_device(sdev, shost) { | |
624 | if ((sdev->channel == starget->channel) && | |
625 | (sdev->id == starget->id)) | |
626 | fn(sdev, data); | |
627 | } | |
628 | } | |
629 | EXPORT_SYMBOL(__starget_for_each_device); | |
630 | ||
1da177e4 LT |
631 | /** |
632 | * __scsi_device_lookup_by_target - find a device given the target (UNLOCKED) | |
633 | * @starget: SCSI target pointer | |
634 | * @lun: SCSI Logical Unit Number | |
635 | * | |
eb44820c RL |
636 | * Description: Looks up the scsi_device with the specified @lun for a given |
637 | * @starget. The returned scsi_device does not have an additional | |
1da177e4 | 638 | * reference. You must hold the host's host_lock over this call and |
32aeef60 HR |
639 | * any access to the returned scsi_device. A scsi_device in state |
640 | * SDEV_DEL is skipped. | |
1da177e4 | 641 | * |
dc8875e1 | 642 | * Note: The only reason why drivers should use this is because |
eb44820c | 643 | * they need to access the device list in irq context. Otherwise you |
1da177e4 LT |
644 | * really want to use scsi_device_lookup_by_target instead. |
645 | **/ | |
646 | struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *starget, | |
9cb78c16 | 647 | u64 lun) |
1da177e4 LT |
648 | { |
649 | struct scsi_device *sdev; | |
650 | ||
651 | list_for_each_entry(sdev, &starget->devices, same_target_siblings) { | |
32aeef60 HR |
652 | if (sdev->sdev_state == SDEV_DEL) |
653 | continue; | |
1da177e4 LT |
654 | if (sdev->lun ==lun) |
655 | return sdev; | |
656 | } | |
657 | ||
658 | return NULL; | |
659 | } | |
660 | EXPORT_SYMBOL(__scsi_device_lookup_by_target); | |
661 | ||
662 | /** | |
663 | * scsi_device_lookup_by_target - find a device given the target | |
664 | * @starget: SCSI target pointer | |
665 | * @lun: SCSI Logical Unit Number | |
666 | * | |
477e608c BZ |
667 | * Description: Looks up the scsi_device with the specified @lun for a given |
668 | * @starget. The returned scsi_device has an additional reference that | |
eb44820c | 669 | * needs to be released with scsi_device_put once you're done with it. |
1da177e4 LT |
670 | **/ |
671 | struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *starget, | |
9cb78c16 | 672 | u64 lun) |
1da177e4 LT |
673 | { |
674 | struct scsi_device *sdev; | |
675 | struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); | |
676 | unsigned long flags; | |
677 | ||
678 | spin_lock_irqsave(shost->host_lock, flags); | |
679 | sdev = __scsi_device_lookup_by_target(starget, lun); | |
680 | if (sdev && scsi_device_get(sdev)) | |
681 | sdev = NULL; | |
682 | spin_unlock_irqrestore(shost->host_lock, flags); | |
683 | ||
684 | return sdev; | |
685 | } | |
686 | EXPORT_SYMBOL(scsi_device_lookup_by_target); | |
687 | ||
688 | /** | |
eb44820c | 689 | * __scsi_device_lookup - find a device given the host (UNLOCKED) |
1da177e4 LT |
690 | * @shost: SCSI host pointer |
691 | * @channel: SCSI channel (zero if only one channel) | |
eb44820c | 692 | * @id: SCSI target number (physical unit number) |
1da177e4 LT |
693 | * @lun: SCSI Logical Unit Number |
694 | * | |
eb44820c RL |
695 | * Description: Looks up the scsi_device with the specified @channel, @id, @lun |
696 | * for a given host. The returned scsi_device does not have an additional | |
697 | * reference. You must hold the host's host_lock over this call and any access | |
698 | * to the returned scsi_device. | |
1da177e4 LT |
699 | * |
700 | * Note: The only reason why drivers would want to use this is because | |
eb44820c | 701 | * they need to access the device list in irq context. Otherwise you |
1da177e4 LT |
702 | * really want to use scsi_device_lookup instead. |
703 | **/ | |
704 | struct scsi_device *__scsi_device_lookup(struct Scsi_Host *shost, | |
9cb78c16 | 705 | uint channel, uint id, u64 lun) |
1da177e4 LT |
706 | { |
707 | struct scsi_device *sdev; | |
708 | ||
709 | list_for_each_entry(sdev, &shost->__devices, siblings) { | |
4ff7adc8 ZZ |
710 | if (sdev->sdev_state == SDEV_DEL) |
711 | continue; | |
1da177e4 LT |
712 | if (sdev->channel == channel && sdev->id == id && |
713 | sdev->lun ==lun) | |
714 | return sdev; | |
715 | } | |
716 | ||
717 | return NULL; | |
718 | } | |
719 | EXPORT_SYMBOL(__scsi_device_lookup); | |
720 | ||
721 | /** | |
722 | * scsi_device_lookup - find a device given the host | |
723 | * @shost: SCSI host pointer | |
724 | * @channel: SCSI channel (zero if only one channel) | |
725 | * @id: SCSI target number (physical unit number) | |
726 | * @lun: SCSI Logical Unit Number | |
727 | * | |
eb44820c RL |
728 | * Description: Looks up the scsi_device with the specified @channel, @id, @lun |
729 | * for a given host. The returned scsi_device has an additional reference that | |
730 | * needs to be released with scsi_device_put once you're done with it. | |
1da177e4 LT |
731 | **/ |
732 | struct scsi_device *scsi_device_lookup(struct Scsi_Host *shost, | |
9cb78c16 | 733 | uint channel, uint id, u64 lun) |
1da177e4 LT |
734 | { |
735 | struct scsi_device *sdev; | |
736 | unsigned long flags; | |
737 | ||
738 | spin_lock_irqsave(shost->host_lock, flags); | |
739 | sdev = __scsi_device_lookup(shost, channel, id, lun); | |
740 | if (sdev && scsi_device_get(sdev)) | |
741 | sdev = NULL; | |
742 | spin_unlock_irqrestore(shost->host_lock, flags); | |
743 | ||
744 | return sdev; | |
745 | } | |
746 | EXPORT_SYMBOL(scsi_device_lookup); | |
747 | ||
1da177e4 LT |
748 | MODULE_DESCRIPTION("SCSI core"); |
749 | MODULE_LICENSE("GPL"); | |
750 | ||
751 | module_param(scsi_logging_level, int, S_IRUGO|S_IWUSR); | |
752 | MODULE_PARM_DESC(scsi_logging_level, "a bit mask of logging levels"); | |
753 | ||
754 | static int __init init_scsi(void) | |
755 | { | |
9bf09c23 | 756 | int error; |
1da177e4 | 757 | |
1da177e4 LT |
758 | error = scsi_init_procfs(); |
759 | if (error) | |
760 | goto cleanup_queue; | |
761 | error = scsi_init_devinfo(); | |
762 | if (error) | |
763 | goto cleanup_procfs; | |
764 | error = scsi_init_hosts(); | |
765 | if (error) | |
766 | goto cleanup_devlist; | |
767 | error = scsi_init_sysctl(); | |
768 | if (error) | |
769 | goto cleanup_hosts; | |
770 | error = scsi_sysfs_register(); | |
771 | if (error) | |
772 | goto cleanup_sysctl; | |
773 | ||
84314fd4 JS |
774 | scsi_netlink_init(); |
775 | ||
1da177e4 LT |
776 | printk(KERN_NOTICE "SCSI subsystem initialized\n"); |
777 | return 0; | |
778 | ||
779 | cleanup_sysctl: | |
780 | scsi_exit_sysctl(); | |
781 | cleanup_hosts: | |
782 | scsi_exit_hosts(); | |
783 | cleanup_devlist: | |
784 | scsi_exit_devinfo(); | |
785 | cleanup_procfs: | |
786 | scsi_exit_procfs(); | |
787 | cleanup_queue: | |
788 | scsi_exit_queue(); | |
789 | printk(KERN_ERR "SCSI subsystem failed to initialize, error = %d\n", | |
790 | -error); | |
791 | return error; | |
792 | } | |
793 | ||
794 | static void __exit exit_scsi(void) | |
795 | { | |
84314fd4 | 796 | scsi_netlink_exit(); |
1da177e4 LT |
797 | scsi_sysfs_unregister(); |
798 | scsi_exit_sysctl(); | |
799 | scsi_exit_hosts(); | |
800 | scsi_exit_devinfo(); | |
1da177e4 LT |
801 | scsi_exit_procfs(); |
802 | scsi_exit_queue(); | |
1da177e4 LT |
803 | } |
804 | ||
805 | subsys_initcall(init_scsi); | |
806 | module_exit(exit_scsi); |