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1da177e4 LT |
1 | /* |
2 | * scsi.c Copyright (C) 1992 Drew Eckhardt | |
3 | * Copyright (C) 1993, 1994, 1995, 1999 Eric Youngdale | |
4 | * Copyright (C) 2002, 2003 Christoph Hellwig | |
5 | * | |
6 | * generic mid-level SCSI driver | |
7 | * Initial versions: Drew Eckhardt | |
8 | * Subsequent revisions: Eric Youngdale | |
9 | * | |
10 | * <drew@colorado.edu> | |
11 | * | |
12 | * Bug correction thanks go to : | |
13 | * Rik Faith <faith@cs.unc.edu> | |
14 | * Tommy Thorn <tthorn> | |
15 | * Thomas Wuensche <tw@fgb1.fgb.mw.tu-muenchen.de> | |
16 | * | |
17 | * Modified by Eric Youngdale eric@andante.org or ericy@gnu.ai.mit.edu to | |
18 | * add scatter-gather, multiple outstanding request, and other | |
19 | * enhancements. | |
20 | * | |
21 | * Native multichannel, wide scsi, /proc/scsi and hot plugging | |
22 | * support added by Michael Neuffer <mike@i-connect.net> | |
23 | * | |
24 | * Added request_module("scsi_hostadapter") for kerneld: | |
25 | * (Put an "alias scsi_hostadapter your_hostadapter" in /etc/modprobe.conf) | |
26 | * Bjorn Ekwall <bj0rn@blox.se> | |
27 | * (changed to kmod) | |
28 | * | |
29 | * Major improvements to the timeout, abort, and reset processing, | |
30 | * as well as performance modifications for large queue depths by | |
31 | * Leonard N. Zubkoff <lnz@dandelion.com> | |
32 | * | |
33 | * Converted cli() code to spinlocks, Ingo Molnar | |
34 | * | |
35 | * Jiffies wrap fixes (host->resetting), 3 Dec 1998 Andrea Arcangeli | |
36 | * | |
37 | * out_of_space hacks, D. Gilbert (dpg) 990608 | |
38 | */ | |
39 | ||
40 | #include <linux/module.h> | |
41 | #include <linux/moduleparam.h> | |
42 | #include <linux/kernel.h> | |
1da177e4 LT |
43 | #include <linux/timer.h> |
44 | #include <linux/string.h> | |
45 | #include <linux/slab.h> | |
46 | #include <linux/blkdev.h> | |
47 | #include <linux/delay.h> | |
48 | #include <linux/init.h> | |
49 | #include <linux/completion.h> | |
1da177e4 LT |
50 | #include <linux/unistd.h> |
51 | #include <linux/spinlock.h> | |
52 | #include <linux/kmod.h> | |
53 | #include <linux/interrupt.h> | |
54 | #include <linux/notifier.h> | |
55 | #include <linux/cpu.h> | |
0b950672 | 56 | #include <linux/mutex.h> |
2955b47d | 57 | #include <linux/async.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 | ||
ea80dade | 88 | /* sd, scsi core and power management need to coordinate flushing async actions */ |
2955b47d | 89 | ASYNC_DOMAIN(scsi_sd_probe_domain); |
a7a20d10 | 90 | EXPORT_SYMBOL(scsi_sd_probe_domain); |
a7a20d10 | 91 | |
3c31b52f DW |
92 | /* |
93 | * Separate domain (from scsi_sd_probe_domain) to maximize the benefit of | |
94 | * asynchronous system resume operations. It is marked 'exclusive' to avoid | |
95 | * being included in the async_synchronize_full() that is invoked by | |
96 | * dpm_resume() | |
97 | */ | |
98 | ASYNC_DOMAIN_EXCLUSIVE(scsi_sd_pm_domain); | |
99 | EXPORT_SYMBOL(scsi_sd_pm_domain); | |
100 | ||
eb44820c RL |
101 | /** |
102 | * scsi_put_command - Free a scsi command block | |
103 | * @cmd: command block to free | |
1da177e4 LT |
104 | * |
105 | * Returns: Nothing. | |
106 | * | |
107 | * Notes: The command must not belong to any lists. | |
108 | */ | |
109 | void scsi_put_command(struct scsi_cmnd *cmd) | |
110 | { | |
1da177e4 | 111 | unsigned long flags; |
b58d9154 | 112 | |
1da177e4 LT |
113 | /* serious error if the command hasn't come from a device list */ |
114 | spin_lock_irqsave(&cmd->device->list_lock, flags); | |
115 | BUG_ON(list_empty(&cmd->list)); | |
116 | list_del_init(&cmd->list); | |
b58d9154 | 117 | spin_unlock_irqrestore(&cmd->device->list_lock, flags); |
1da177e4 | 118 | |
fcc95a76 | 119 | BUG_ON(delayed_work_pending(&cmd->abort_work)); |
de25deb1 FT |
120 | } |
121 | ||
1da177e4 LT |
122 | #ifdef CONFIG_SCSI_LOGGING |
123 | void scsi_log_send(struct scsi_cmnd *cmd) | |
124 | { | |
125 | unsigned int level; | |
1da177e4 LT |
126 | |
127 | /* | |
128 | * If ML QUEUE log level is greater than or equal to: | |
129 | * | |
130 | * 1: nothing (match completion) | |
131 | * | |
c11c004b | 132 | * 2: log opcode + command of all commands + cmd address |
1da177e4 | 133 | * |
c11c004b | 134 | * 3: same as 2 |
1da177e4 | 135 | * |
a4a6afb4 | 136 | * 4: same as 3 |
1da177e4 LT |
137 | */ |
138 | if (unlikely(scsi_logging_level)) { | |
139 | level = SCSI_LOG_LEVEL(SCSI_LOG_MLQUEUE_SHIFT, | |
140 | SCSI_LOG_MLQUEUE_BITS); | |
141 | if (level > 1) { | |
c11c004b HR |
142 | scmd_printk(KERN_INFO, cmd, |
143 | "Send: scmd 0x%p\n", cmd); | |
1da177e4 | 144 | scsi_print_command(cmd); |
1da177e4 LT |
145 | } |
146 | } | |
147 | } | |
148 | ||
149 | void scsi_log_completion(struct scsi_cmnd *cmd, int disposition) | |
150 | { | |
151 | unsigned int level; | |
1da177e4 LT |
152 | |
153 | /* | |
154 | * If ML COMPLETE log level is greater than or equal to: | |
155 | * | |
156 | * 1: log disposition, result, opcode + command, and conditionally | |
157 | * sense data for failures or non SUCCESS dispositions. | |
158 | * | |
159 | * 2: same as 1 but for all command completions. | |
160 | * | |
c11c004b | 161 | * 3: same as 2 |
1da177e4 LT |
162 | * |
163 | * 4: same as 3 plus dump extra junk | |
164 | */ | |
165 | if (unlikely(scsi_logging_level)) { | |
166 | level = SCSI_LOG_LEVEL(SCSI_LOG_MLCOMPLETE_SHIFT, | |
167 | SCSI_LOG_MLCOMPLETE_BITS); | |
168 | if (((level > 0) && (cmd->result || disposition != SUCCESS)) || | |
169 | (level > 1)) { | |
026f8da8 | 170 | scsi_print_result(cmd, "Done", disposition); |
1da177e4 | 171 | scsi_print_command(cmd); |
a4d04a4c | 172 | if (status_byte(cmd->result) & CHECK_CONDITION) |
d811b848 | 173 | scsi_print_sense(cmd); |
a4d04a4c MP |
174 | if (level > 3) |
175 | scmd_printk(KERN_INFO, cmd, | |
176 | "scsi host busy %d failed %d\n", | |
74665016 | 177 | atomic_read(&cmd->device->host->host_busy), |
a4d04a4c | 178 | cmd->device->host->host_failed); |
1da177e4 LT |
179 | } |
180 | } | |
181 | } | |
182 | #endif | |
183 | ||
eb44820c RL |
184 | /** |
185 | * scsi_cmd_get_serial - Assign a serial number to a command | |
186 | * @host: the scsi host | |
187 | * @cmd: command to assign serial number to | |
188 | * | |
189 | * Description: a serial number identifies a request for error recovery | |
1da177e4 LT |
190 | * and debugging purposes. Protected by the Host_Lock of host. |
191 | */ | |
f281233d | 192 | void scsi_cmd_get_serial(struct Scsi_Host *host, struct scsi_cmnd *cmd) |
1da177e4 LT |
193 | { |
194 | cmd->serial_number = host->cmd_serial_number++; | |
195 | if (cmd->serial_number == 0) | |
196 | cmd->serial_number = host->cmd_serial_number++; | |
1da177e4 | 197 | } |
f281233d | 198 | EXPORT_SYMBOL(scsi_cmd_get_serial); |
1da177e4 | 199 | |
eb44820c RL |
200 | /** |
201 | * scsi_finish_command - cleanup and pass command back to upper layer | |
202 | * @cmd: the command | |
1da177e4 | 203 | * |
eb44820c | 204 | * Description: Pass command off to upper layer for finishing of I/O |
1da177e4 LT |
205 | * request, waking processes that are waiting on results, |
206 | * etc. | |
207 | */ | |
208 | void scsi_finish_command(struct scsi_cmnd *cmd) | |
209 | { | |
210 | struct scsi_device *sdev = cmd->device; | |
f0c0a376 | 211 | struct scsi_target *starget = scsi_target(sdev); |
1da177e4 | 212 | struct Scsi_Host *shost = sdev->host; |
7b3d9545 LT |
213 | struct scsi_driver *drv; |
214 | unsigned int good_bytes; | |
1da177e4 LT |
215 | |
216 | scsi_device_unbusy(sdev); | |
217 | ||
cd9070c9 CH |
218 | /* |
219 | * Clear the flags that say that the device/target/host is no longer | |
220 | * capable of accepting new commands. | |
221 | */ | |
222 | if (atomic_read(&shost->host_blocked)) | |
223 | atomic_set(&shost->host_blocked, 0); | |
224 | if (atomic_read(&starget->target_blocked)) | |
225 | atomic_set(&starget->target_blocked, 0); | |
226 | if (atomic_read(&sdev->device_blocked)) | |
227 | atomic_set(&sdev->device_blocked, 0); | |
1da177e4 LT |
228 | |
229 | /* | |
230 | * If we have valid sense information, then some kind of recovery | |
231 | * must have taken place. Make a note of this. | |
232 | */ | |
233 | if (SCSI_SENSE_VALID(cmd)) | |
234 | cmd->result |= (DRIVER_SENSE << 24); | |
235 | ||
3bf743e7 JG |
236 | SCSI_LOG_MLCOMPLETE(4, sdev_printk(KERN_INFO, sdev, |
237 | "Notifying upper driver of completion " | |
238 | "(result %x)\n", cmd->result)); | |
1da177e4 | 239 | |
f18573ab | 240 | good_bytes = scsi_bufflen(cmd); |
57292b58 | 241 | if (!blk_rq_is_passthrough(cmd->request)) { |
427e59f0 | 242 | int old_good_bytes = good_bytes; |
7b3d9545 LT |
243 | drv = scsi_cmd_to_driver(cmd); |
244 | if (drv->done) | |
245 | good_bytes = drv->done(cmd); | |
427e59f0 JB |
246 | /* |
247 | * USB may not give sense identifying bad sector and | |
248 | * simply return a residue instead, so subtract off the | |
249 | * residue if drv->done() error processing indicates no | |
250 | * change to the completion length. | |
251 | */ | |
252 | if (good_bytes == old_good_bytes) | |
253 | good_bytes -= scsi_get_resid(cmd); | |
7b3d9545 LT |
254 | } |
255 | scsi_io_completion(cmd, good_bytes); | |
1da177e4 | 256 | } |
1da177e4 | 257 | |
eb44820c | 258 | /** |
db5ed4df | 259 | * scsi_change_queue_depth - change a device's queue depth |
eb44820c | 260 | * @sdev: SCSI Device in question |
db5ed4df | 261 | * @depth: number of commands allowed to be queued to the driver |
1da177e4 | 262 | * |
db5ed4df | 263 | * Sets the device queue depth and returns the new value. |
1da177e4 | 264 | */ |
db5ed4df | 265 | int scsi_change_queue_depth(struct scsi_device *sdev, int depth) |
1da177e4 | 266 | { |
64d513ac CH |
267 | if (depth > 0) { |
268 | sdev->queue_depth = depth; | |
269 | wmb(); | |
885ace9e | 270 | } |
1da177e4 | 271 | |
d278d4a8 JA |
272 | if (sdev->request_queue) |
273 | blk_set_queue_depth(sdev->request_queue, depth); | |
274 | ||
db5ed4df | 275 | return sdev->queue_depth; |
1da177e4 | 276 | } |
db5ed4df | 277 | EXPORT_SYMBOL(scsi_change_queue_depth); |
1da177e4 | 278 | |
eb44820c RL |
279 | /** |
280 | * scsi_track_queue_full - track QUEUE_FULL events to adjust queue depth | |
281 | * @sdev: SCSI Device in question | |
282 | * @depth: Current number of outstanding SCSI commands on this device, | |
283 | * not counting the one returned as QUEUE_FULL. | |
1da177e4 | 284 | * |
eb44820c | 285 | * Description: This function will track successive QUEUE_FULL events on a |
1da177e4 LT |
286 | * specific SCSI device to determine if and when there is a |
287 | * need to adjust the queue depth on the device. | |
288 | * | |
eb44820c | 289 | * Returns: 0 - No change needed, >0 - Adjust queue depth to this new depth, |
1da177e4 LT |
290 | * -1 - Drop back to untagged operation using host->cmd_per_lun |
291 | * as the untagged command depth | |
292 | * | |
293 | * Lock Status: None held on entry | |
294 | * | |
295 | * Notes: Low level drivers may call this at any time and we will do | |
296 | * "The Right Thing." We are interrupt context safe. | |
297 | */ | |
298 | int scsi_track_queue_full(struct scsi_device *sdev, int depth) | |
299 | { | |
4a84067d VD |
300 | |
301 | /* | |
302 | * Don't let QUEUE_FULLs on the same | |
303 | * jiffies count, they could all be from | |
304 | * same event. | |
305 | */ | |
306 | if ((jiffies >> 4) == (sdev->last_queue_full_time >> 4)) | |
1da177e4 LT |
307 | return 0; |
308 | ||
4a84067d | 309 | sdev->last_queue_full_time = jiffies; |
1da177e4 LT |
310 | if (sdev->last_queue_full_depth != depth) { |
311 | sdev->last_queue_full_count = 1; | |
312 | sdev->last_queue_full_depth = depth; | |
313 | } else { | |
314 | sdev->last_queue_full_count++; | |
315 | } | |
316 | ||
317 | if (sdev->last_queue_full_count <= 10) | |
318 | return 0; | |
609aa22f | 319 | |
db5ed4df | 320 | return scsi_change_queue_depth(sdev, depth); |
1da177e4 LT |
321 | } |
322 | EXPORT_SYMBOL(scsi_track_queue_full); | |
323 | ||
881a256d MW |
324 | /** |
325 | * scsi_vpd_inquiry - Request a device provide us with a VPD page | |
326 | * @sdev: The device to ask | |
327 | * @buffer: Where to put the result | |
328 | * @page: Which Vital Product Data to return | |
329 | * @len: The length of the buffer | |
330 | * | |
331 | * This is an internal helper function. You probably want to use | |
332 | * scsi_get_vpd_page instead. | |
333 | * | |
bc8945df | 334 | * Returns size of the vpd page on success or a negative error number. |
881a256d MW |
335 | */ |
336 | static int scsi_vpd_inquiry(struct scsi_device *sdev, unsigned char *buffer, | |
337 | u8 page, unsigned len) | |
338 | { | |
339 | int result; | |
340 | unsigned char cmd[16]; | |
341 | ||
bc8945df HR |
342 | if (len < 4) |
343 | return -EINVAL; | |
344 | ||
881a256d MW |
345 | cmd[0] = INQUIRY; |
346 | cmd[1] = 1; /* EVPD */ | |
347 | cmd[2] = page; | |
348 | cmd[3] = len >> 8; | |
349 | cmd[4] = len & 0xff; | |
350 | cmd[5] = 0; /* Control byte */ | |
351 | ||
352 | /* | |
353 | * I'm not convinced we need to try quite this hard to get VPD, but | |
354 | * all the existing users tried this hard. | |
355 | */ | |
356 | result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buffer, | |
95a3639e | 357 | len, NULL, 30 * HZ, 3, NULL); |
881a256d | 358 | if (result) |
bc8945df | 359 | return -EIO; |
881a256d MW |
360 | |
361 | /* Sanity check that we got the page back that we asked for */ | |
362 | if (buffer[1] != page) | |
363 | return -EIO; | |
364 | ||
bc8945df | 365 | return get_unaligned_be16(&buffer[2]) + 4; |
881a256d MW |
366 | } |
367 | ||
368 | /** | |
369 | * scsi_get_vpd_page - Get Vital Product Data from a SCSI device | |
370 | * @sdev: The device to ask | |
371 | * @page: Which Vital Product Data to return | |
786f8ba2 RD |
372 | * @buf: where to store the VPD |
373 | * @buf_len: number of bytes in the VPD buffer area | |
881a256d MW |
374 | * |
375 | * SCSI devices may optionally supply Vital Product Data. Each 'page' | |
376 | * of VPD is defined in the appropriate SCSI document (eg SPC, SBC). | |
377 | * If the device supports this VPD page, this routine returns a pointer | |
378 | * to a buffer containing the data from that page. The caller is | |
379 | * responsible for calling kfree() on this pointer when it is no longer | |
380 | * needed. If we cannot retrieve the VPD page this routine returns %NULL. | |
381 | */ | |
e3deec09 JB |
382 | int scsi_get_vpd_page(struct scsi_device *sdev, u8 page, unsigned char *buf, |
383 | int buf_len) | |
881a256d MW |
384 | { |
385 | int i, result; | |
881a256d | 386 | |
7562523e MP |
387 | if (sdev->skip_vpd_pages) |
388 | goto fail; | |
389 | ||
881a256d | 390 | /* Ask for all the pages supported by this device */ |
e3deec09 | 391 | result = scsi_vpd_inquiry(sdev, buf, 0, buf_len); |
bc8945df | 392 | if (result < 4) |
881a256d MW |
393 | goto fail; |
394 | ||
395 | /* If the user actually wanted this page, we can skip the rest */ | |
396 | if (page == 0) | |
16d3ea26 | 397 | return 0; |
881a256d | 398 | |
bc8945df HR |
399 | for (i = 4; i < min(result, buf_len); i++) |
400 | if (buf[i] == page) | |
881a256d | 401 | goto found; |
e3deec09 | 402 | |
bc8945df | 403 | if (i < result && i >= buf_len) |
e3deec09 JB |
404 | /* ran off the end of the buffer, give us benefit of doubt */ |
405 | goto found; | |
881a256d MW |
406 | /* The device claims it doesn't support the requested page */ |
407 | goto fail; | |
408 | ||
409 | found: | |
e3deec09 | 410 | result = scsi_vpd_inquiry(sdev, buf, page, buf_len); |
bc8945df | 411 | if (result < 0) |
881a256d MW |
412 | goto fail; |
413 | ||
e3deec09 | 414 | return 0; |
881a256d MW |
415 | |
416 | fail: | |
e3deec09 | 417 | return -EINVAL; |
881a256d MW |
418 | } |
419 | EXPORT_SYMBOL_GPL(scsi_get_vpd_page); | |
420 | ||
b3ae8780 HR |
421 | /** |
422 | * scsi_attach_vpd - Attach Vital Product Data to a SCSI device structure | |
423 | * @sdev: The device to ask | |
424 | * | |
425 | * Attach the 'Device Identification' VPD page (0x83) and the | |
426 | * 'Unit Serial Number' VPD page (0x80) to a SCSI device | |
427 | * structure. This information can be used to identify the device | |
428 | * uniquely. | |
429 | */ | |
430 | void scsi_attach_vpd(struct scsi_device *sdev) | |
431 | { | |
432 | int result, i; | |
433 | int vpd_len = SCSI_VPD_PG_LEN; | |
434 | int pg80_supported = 0; | |
435 | int pg83_supported = 0; | |
09e2b0b1 | 436 | unsigned char __rcu *vpd_buf, *orig_vpd_buf = NULL; |
b3ae8780 | 437 | |
5ddfe085 | 438 | if (!scsi_device_supports_vpd(sdev)) |
b3ae8780 | 439 | return; |
5ddfe085 | 440 | |
b3ae8780 HR |
441 | retry_pg0: |
442 | vpd_buf = kmalloc(vpd_len, GFP_KERNEL); | |
443 | if (!vpd_buf) | |
444 | return; | |
445 | ||
446 | /* Ask for all the pages supported by this device */ | |
447 | result = scsi_vpd_inquiry(sdev, vpd_buf, 0, vpd_len); | |
448 | if (result < 0) { | |
449 | kfree(vpd_buf); | |
450 | return; | |
451 | } | |
452 | if (result > vpd_len) { | |
453 | vpd_len = result; | |
454 | kfree(vpd_buf); | |
455 | goto retry_pg0; | |
456 | } | |
457 | ||
458 | for (i = 4; i < result; i++) { | |
459 | if (vpd_buf[i] == 0x80) | |
460 | pg80_supported = 1; | |
461 | if (vpd_buf[i] == 0x83) | |
462 | pg83_supported = 1; | |
463 | } | |
464 | kfree(vpd_buf); | |
465 | vpd_len = SCSI_VPD_PG_LEN; | |
466 | ||
467 | if (pg80_supported) { | |
468 | retry_pg80: | |
469 | vpd_buf = kmalloc(vpd_len, GFP_KERNEL); | |
470 | if (!vpd_buf) | |
471 | return; | |
472 | ||
473 | result = scsi_vpd_inquiry(sdev, vpd_buf, 0x80, vpd_len); | |
474 | if (result < 0) { | |
475 | kfree(vpd_buf); | |
476 | return; | |
477 | } | |
478 | if (result > vpd_len) { | |
479 | vpd_len = result; | |
480 | kfree(vpd_buf); | |
481 | goto retry_pg80; | |
482 | } | |
09e2b0b1 HR |
483 | mutex_lock(&sdev->inquiry_mutex); |
484 | orig_vpd_buf = sdev->vpd_pg80; | |
b3ae8780 | 485 | sdev->vpd_pg80_len = result; |
09e2b0b1 HR |
486 | rcu_assign_pointer(sdev->vpd_pg80, vpd_buf); |
487 | mutex_unlock(&sdev->inquiry_mutex); | |
488 | synchronize_rcu(); | |
489 | if (orig_vpd_buf) { | |
490 | kfree(orig_vpd_buf); | |
491 | orig_vpd_buf = NULL; | |
492 | } | |
b3ae8780 HR |
493 | vpd_len = SCSI_VPD_PG_LEN; |
494 | } | |
495 | ||
496 | if (pg83_supported) { | |
497 | retry_pg83: | |
498 | vpd_buf = kmalloc(vpd_len, GFP_KERNEL); | |
499 | if (!vpd_buf) | |
500 | return; | |
501 | ||
502 | result = scsi_vpd_inquiry(sdev, vpd_buf, 0x83, vpd_len); | |
503 | if (result < 0) { | |
504 | kfree(vpd_buf); | |
505 | return; | |
506 | } | |
507 | if (result > vpd_len) { | |
508 | vpd_len = result; | |
509 | kfree(vpd_buf); | |
510 | goto retry_pg83; | |
511 | } | |
09e2b0b1 HR |
512 | mutex_lock(&sdev->inquiry_mutex); |
513 | orig_vpd_buf = sdev->vpd_pg83; | |
b3ae8780 | 514 | sdev->vpd_pg83_len = result; |
09e2b0b1 HR |
515 | rcu_assign_pointer(sdev->vpd_pg83, vpd_buf); |
516 | mutex_unlock(&sdev->inquiry_mutex); | |
517 | synchronize_rcu(); | |
518 | if (orig_vpd_buf) | |
519 | kfree(orig_vpd_buf); | |
b3ae8780 HR |
520 | } |
521 | } | |
522 | ||
3c6bdaea MP |
523 | /** |
524 | * scsi_report_opcode - Find out if a given command opcode is supported | |
525 | * @sdev: scsi device to query | |
526 | * @buffer: scratch buffer (must be at least 20 bytes long) | |
527 | * @len: length of buffer | |
528 | * @opcode: opcode for command to look up | |
529 | * | |
530 | * Uses the REPORT SUPPORTED OPERATION CODES to look up the given | |
66c28f97 MP |
531 | * opcode. Returns -EINVAL if RSOC fails, 0 if the command opcode is |
532 | * unsupported and 1 if the device claims to support the command. | |
3c6bdaea MP |
533 | */ |
534 | int scsi_report_opcode(struct scsi_device *sdev, unsigned char *buffer, | |
535 | unsigned int len, unsigned char opcode) | |
536 | { | |
537 | unsigned char cmd[16]; | |
538 | struct scsi_sense_hdr sshdr; | |
539 | int result; | |
540 | ||
541 | if (sdev->no_report_opcodes || sdev->scsi_level < SCSI_SPC_3) | |
66c28f97 | 542 | return -EINVAL; |
3c6bdaea MP |
543 | |
544 | memset(cmd, 0, 16); | |
545 | cmd[0] = MAINTENANCE_IN; | |
546 | cmd[1] = MI_REPORT_SUPPORTED_OPERATION_CODES; | |
547 | cmd[2] = 1; /* One command format */ | |
548 | cmd[3] = opcode; | |
549 | put_unaligned_be32(len, &cmd[6]); | |
550 | memset(buffer, 0, len); | |
551 | ||
552 | result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buffer, len, | |
553 | &sshdr, 30 * HZ, 3, NULL); | |
554 | ||
555 | if (result && scsi_sense_valid(&sshdr) && | |
556 | sshdr.sense_key == ILLEGAL_REQUEST && | |
557 | (sshdr.asc == 0x20 || sshdr.asc == 0x24) && sshdr.ascq == 0x00) | |
66c28f97 | 558 | return -EINVAL; |
3c6bdaea MP |
559 | |
560 | if ((buffer[1] & 3) == 3) /* Command supported */ | |
561 | return 1; | |
562 | ||
563 | return 0; | |
564 | } | |
565 | EXPORT_SYMBOL(scsi_report_opcode); | |
566 | ||
1da177e4 | 567 | /** |
eb44820c | 568 | * scsi_device_get - get an additional reference to a scsi_device |
1da177e4 LT |
569 | * @sdev: device to get a reference to |
570 | * | |
eb44820c | 571 | * Description: Gets a reference to the scsi_device and increments the use count |
1da177e4 LT |
572 | * of the underlying LLDD module. You must hold host_lock of the |
573 | * parent Scsi_Host or already have a reference when calling this. | |
cff549e4 CH |
574 | * |
575 | * This will fail if a device is deleted or cancelled, or when the LLD module | |
576 | * is in the process of being unloaded. | |
1da177e4 LT |
577 | */ |
578 | int scsi_device_get(struct scsi_device *sdev) | |
579 | { | |
cff549e4 CH |
580 | if (sdev->sdev_state == SDEV_DEL || sdev->sdev_state == SDEV_CANCEL) |
581 | goto fail; | |
1da177e4 | 582 | if (!get_device(&sdev->sdev_gendev)) |
cff549e4 CH |
583 | goto fail; |
584 | if (!try_module_get(sdev->host->hostt->module)) | |
585 | goto fail_put_device; | |
1da177e4 | 586 | return 0; |
cff549e4 CH |
587 | |
588 | fail_put_device: | |
589 | put_device(&sdev->sdev_gendev); | |
590 | fail: | |
591 | return -ENXIO; | |
1da177e4 LT |
592 | } |
593 | EXPORT_SYMBOL(scsi_device_get); | |
594 | ||
595 | /** | |
596 | * scsi_device_put - release a reference to a scsi_device | |
597 | * @sdev: device to release a reference on. | |
598 | * | |
eb44820c RL |
599 | * Description: Release a reference to the scsi_device and decrements the use |
600 | * count of the underlying LLDD module. The device is freed once the last | |
1da177e4 LT |
601 | * user vanishes. |
602 | */ | |
603 | void scsi_device_put(struct scsi_device *sdev) | |
604 | { | |
dc4515ea | 605 | module_put(sdev->host->hostt->module); |
1da177e4 LT |
606 | put_device(&sdev->sdev_gendev); |
607 | } | |
608 | EXPORT_SYMBOL(scsi_device_put); | |
609 | ||
eb44820c | 610 | /* helper for shost_for_each_device, see that for documentation */ |
1da177e4 LT |
611 | struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *shost, |
612 | struct scsi_device *prev) | |
613 | { | |
614 | struct list_head *list = (prev ? &prev->siblings : &shost->__devices); | |
615 | struct scsi_device *next = NULL; | |
616 | unsigned long flags; | |
617 | ||
618 | spin_lock_irqsave(shost->host_lock, flags); | |
619 | while (list->next != &shost->__devices) { | |
620 | next = list_entry(list->next, struct scsi_device, siblings); | |
621 | /* skip devices that we can't get a reference to */ | |
622 | if (!scsi_device_get(next)) | |
623 | break; | |
624 | next = NULL; | |
625 | list = list->next; | |
626 | } | |
627 | spin_unlock_irqrestore(shost->host_lock, flags); | |
628 | ||
629 | if (prev) | |
630 | scsi_device_put(prev); | |
631 | return next; | |
632 | } | |
633 | EXPORT_SYMBOL(__scsi_iterate_devices); | |
634 | ||
635 | /** | |
636 | * starget_for_each_device - helper to walk all devices of a target | |
637 | * @starget: target whose devices we want to iterate over. | |
eb44820c RL |
638 | * @data: Opaque passed to each function call. |
639 | * @fn: Function to call on each device | |
1da177e4 | 640 | * |
522939d4 | 641 | * This traverses over each device of @starget. The devices have |
1da177e4 LT |
642 | * a reference that must be released by scsi_host_put when breaking |
643 | * out of the loop. | |
644 | */ | |
522939d4 | 645 | void starget_for_each_device(struct scsi_target *starget, void *data, |
1da177e4 LT |
646 | void (*fn)(struct scsi_device *, void *)) |
647 | { | |
648 | struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); | |
649 | struct scsi_device *sdev; | |
650 | ||
651 | shost_for_each_device(sdev, shost) { | |
652 | if ((sdev->channel == starget->channel) && | |
653 | (sdev->id == starget->id)) | |
654 | fn(sdev, data); | |
655 | } | |
656 | } | |
657 | EXPORT_SYMBOL(starget_for_each_device); | |
658 | ||
522939d4 | 659 | /** |
14f501a4 | 660 | * __starget_for_each_device - helper to walk all devices of a target (UNLOCKED) |
522939d4 | 661 | * @starget: target whose devices we want to iterate over. |
14f501a4 RD |
662 | * @data: parameter for callback @fn() |
663 | * @fn: callback function that is invoked for each device | |
522939d4 MR |
664 | * |
665 | * This traverses over each device of @starget. It does _not_ | |
666 | * take a reference on the scsi_device, so the whole loop must be | |
667 | * protected by shost->host_lock. | |
668 | * | |
669 | * Note: The only reason why drivers would want to use this is because | |
670 | * they need to access the device list in irq context. Otherwise you | |
671 | * really want to use starget_for_each_device instead. | |
672 | **/ | |
673 | void __starget_for_each_device(struct scsi_target *starget, void *data, | |
674 | void (*fn)(struct scsi_device *, void *)) | |
675 | { | |
676 | struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); | |
677 | struct scsi_device *sdev; | |
678 | ||
679 | __shost_for_each_device(sdev, shost) { | |
680 | if ((sdev->channel == starget->channel) && | |
681 | (sdev->id == starget->id)) | |
682 | fn(sdev, data); | |
683 | } | |
684 | } | |
685 | EXPORT_SYMBOL(__starget_for_each_device); | |
686 | ||
1da177e4 LT |
687 | /** |
688 | * __scsi_device_lookup_by_target - find a device given the target (UNLOCKED) | |
689 | * @starget: SCSI target pointer | |
690 | * @lun: SCSI Logical Unit Number | |
691 | * | |
eb44820c RL |
692 | * Description: Looks up the scsi_device with the specified @lun for a given |
693 | * @starget. The returned scsi_device does not have an additional | |
1da177e4 | 694 | * reference. You must hold the host's host_lock over this call and |
32aeef60 HR |
695 | * any access to the returned scsi_device. A scsi_device in state |
696 | * SDEV_DEL is skipped. | |
1da177e4 | 697 | * |
dc8875e1 | 698 | * Note: The only reason why drivers should use this is because |
eb44820c | 699 | * they need to access the device list in irq context. Otherwise you |
1da177e4 LT |
700 | * really want to use scsi_device_lookup_by_target instead. |
701 | **/ | |
702 | struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *starget, | |
9cb78c16 | 703 | u64 lun) |
1da177e4 LT |
704 | { |
705 | struct scsi_device *sdev; | |
706 | ||
707 | list_for_each_entry(sdev, &starget->devices, same_target_siblings) { | |
32aeef60 HR |
708 | if (sdev->sdev_state == SDEV_DEL) |
709 | continue; | |
1da177e4 LT |
710 | if (sdev->lun ==lun) |
711 | return sdev; | |
712 | } | |
713 | ||
714 | return NULL; | |
715 | } | |
716 | EXPORT_SYMBOL(__scsi_device_lookup_by_target); | |
717 | ||
718 | /** | |
719 | * scsi_device_lookup_by_target - find a device given the target | |
720 | * @starget: SCSI target pointer | |
721 | * @lun: SCSI Logical Unit Number | |
722 | * | |
477e608c BZ |
723 | * Description: Looks up the scsi_device with the specified @lun for a given |
724 | * @starget. The returned scsi_device has an additional reference that | |
eb44820c | 725 | * needs to be released with scsi_device_put once you're done with it. |
1da177e4 LT |
726 | **/ |
727 | struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *starget, | |
9cb78c16 | 728 | u64 lun) |
1da177e4 LT |
729 | { |
730 | struct scsi_device *sdev; | |
731 | struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); | |
732 | unsigned long flags; | |
733 | ||
734 | spin_lock_irqsave(shost->host_lock, flags); | |
735 | sdev = __scsi_device_lookup_by_target(starget, lun); | |
736 | if (sdev && scsi_device_get(sdev)) | |
737 | sdev = NULL; | |
738 | spin_unlock_irqrestore(shost->host_lock, flags); | |
739 | ||
740 | return sdev; | |
741 | } | |
742 | EXPORT_SYMBOL(scsi_device_lookup_by_target); | |
743 | ||
744 | /** | |
eb44820c | 745 | * __scsi_device_lookup - find a device given the host (UNLOCKED) |
1da177e4 LT |
746 | * @shost: SCSI host pointer |
747 | * @channel: SCSI channel (zero if only one channel) | |
eb44820c | 748 | * @id: SCSI target number (physical unit number) |
1da177e4 LT |
749 | * @lun: SCSI Logical Unit Number |
750 | * | |
eb44820c RL |
751 | * Description: Looks up the scsi_device with the specified @channel, @id, @lun |
752 | * for a given host. The returned scsi_device does not have an additional | |
753 | * reference. You must hold the host's host_lock over this call and any access | |
754 | * to the returned scsi_device. | |
1da177e4 LT |
755 | * |
756 | * Note: The only reason why drivers would want to use this is because | |
eb44820c | 757 | * they need to access the device list in irq context. Otherwise you |
1da177e4 LT |
758 | * really want to use scsi_device_lookup instead. |
759 | **/ | |
760 | struct scsi_device *__scsi_device_lookup(struct Scsi_Host *shost, | |
9cb78c16 | 761 | uint channel, uint id, u64 lun) |
1da177e4 LT |
762 | { |
763 | struct scsi_device *sdev; | |
764 | ||
765 | list_for_each_entry(sdev, &shost->__devices, siblings) { | |
4ff7adc8 ZZ |
766 | if (sdev->sdev_state == SDEV_DEL) |
767 | continue; | |
1da177e4 LT |
768 | if (sdev->channel == channel && sdev->id == id && |
769 | sdev->lun ==lun) | |
770 | return sdev; | |
771 | } | |
772 | ||
773 | return NULL; | |
774 | } | |
775 | EXPORT_SYMBOL(__scsi_device_lookup); | |
776 | ||
777 | /** | |
778 | * scsi_device_lookup - find a device given the host | |
779 | * @shost: SCSI host pointer | |
780 | * @channel: SCSI channel (zero if only one channel) | |
781 | * @id: SCSI target number (physical unit number) | |
782 | * @lun: SCSI Logical Unit Number | |
783 | * | |
eb44820c RL |
784 | * Description: Looks up the scsi_device with the specified @channel, @id, @lun |
785 | * for a given host. The returned scsi_device has an additional reference that | |
786 | * needs to be released with scsi_device_put once you're done with it. | |
1da177e4 LT |
787 | **/ |
788 | struct scsi_device *scsi_device_lookup(struct Scsi_Host *shost, | |
9cb78c16 | 789 | uint channel, uint id, u64 lun) |
1da177e4 LT |
790 | { |
791 | struct scsi_device *sdev; | |
792 | unsigned long flags; | |
793 | ||
794 | spin_lock_irqsave(shost->host_lock, flags); | |
795 | sdev = __scsi_device_lookup(shost, channel, id, lun); | |
796 | if (sdev && scsi_device_get(sdev)) | |
797 | sdev = NULL; | |
798 | spin_unlock_irqrestore(shost->host_lock, flags); | |
799 | ||
800 | return sdev; | |
801 | } | |
802 | EXPORT_SYMBOL(scsi_device_lookup); | |
803 | ||
1da177e4 LT |
804 | MODULE_DESCRIPTION("SCSI core"); |
805 | MODULE_LICENSE("GPL"); | |
806 | ||
807 | module_param(scsi_logging_level, int, S_IRUGO|S_IWUSR); | |
808 | MODULE_PARM_DESC(scsi_logging_level, "a bit mask of logging levels"); | |
809 | ||
24c20f10 CH |
810 | #ifdef CONFIG_SCSI_MQ_DEFAULT |
811 | bool scsi_use_blk_mq = true; | |
812 | #else | |
d285203c | 813 | bool scsi_use_blk_mq = false; |
24c20f10 | 814 | #endif |
d285203c CH |
815 | module_param_named(use_blk_mq, scsi_use_blk_mq, bool, S_IWUSR | S_IRUGO); |
816 | ||
1da177e4 LT |
817 | static int __init init_scsi(void) |
818 | { | |
9bf09c23 | 819 | int error; |
1da177e4 LT |
820 | |
821 | error = scsi_init_queue(); | |
822 | if (error) | |
823 | return error; | |
824 | error = scsi_init_procfs(); | |
825 | if (error) | |
826 | goto cleanup_queue; | |
827 | error = scsi_init_devinfo(); | |
828 | if (error) | |
829 | goto cleanup_procfs; | |
830 | error = scsi_init_hosts(); | |
831 | if (error) | |
832 | goto cleanup_devlist; | |
833 | error = scsi_init_sysctl(); | |
834 | if (error) | |
835 | goto cleanup_hosts; | |
836 | error = scsi_sysfs_register(); | |
837 | if (error) | |
838 | goto cleanup_sysctl; | |
839 | ||
84314fd4 JS |
840 | scsi_netlink_init(); |
841 | ||
1da177e4 LT |
842 | printk(KERN_NOTICE "SCSI subsystem initialized\n"); |
843 | return 0; | |
844 | ||
845 | cleanup_sysctl: | |
846 | scsi_exit_sysctl(); | |
847 | cleanup_hosts: | |
848 | scsi_exit_hosts(); | |
849 | cleanup_devlist: | |
850 | scsi_exit_devinfo(); | |
851 | cleanup_procfs: | |
852 | scsi_exit_procfs(); | |
853 | cleanup_queue: | |
854 | scsi_exit_queue(); | |
855 | printk(KERN_ERR "SCSI subsystem failed to initialize, error = %d\n", | |
856 | -error); | |
857 | return error; | |
858 | } | |
859 | ||
860 | static void __exit exit_scsi(void) | |
861 | { | |
84314fd4 | 862 | scsi_netlink_exit(); |
1da177e4 LT |
863 | scsi_sysfs_unregister(); |
864 | scsi_exit_sysctl(); | |
865 | scsi_exit_hosts(); | |
866 | scsi_exit_devinfo(); | |
1da177e4 LT |
867 | scsi_exit_procfs(); |
868 | scsi_exit_queue(); | |
a4683487 | 869 | async_unregister_domain(&scsi_sd_probe_domain); |
1da177e4 LT |
870 | } |
871 | ||
872 | subsys_initcall(init_scsi); | |
873 | module_exit(exit_scsi); |