]>
Commit | Line | Data |
---|---|---|
ece1d636 TH |
1 | /* |
2 | * libata-eh.c - libata error handling | |
3 | * | |
4 | * Maintained by: Jeff Garzik <jgarzik@pobox.com> | |
5 | * Please ALWAYS copy linux-ide@vger.kernel.org | |
6 | * on emails. | |
7 | * | |
8 | * Copyright 2006 Tejun Heo <htejun@gmail.com> | |
9 | * | |
10 | * | |
11 | * This program is free software; you can redistribute it and/or | |
12 | * modify it under the terms of the GNU General Public License as | |
13 | * published by the Free Software Foundation; either version 2, or | |
14 | * (at your option) any later version. | |
15 | * | |
16 | * This program is distributed in the hope that it will be useful, | |
17 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
18 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
19 | * General Public License for more details. | |
20 | * | |
21 | * You should have received a copy of the GNU General Public License | |
22 | * along with this program; see the file COPYING. If not, write to | |
23 | * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, | |
24 | * USA. | |
25 | * | |
26 | * | |
27 | * libata documentation is available via 'make {ps|pdf}docs', | |
28 | * as Documentation/DocBook/libata.* | |
29 | * | |
30 | * Hardware documentation available from http://www.t13.org/ and | |
31 | * http://www.sata-io.org/ | |
32 | * | |
33 | */ | |
34 | ||
35 | #include <linux/config.h> | |
36 | #include <linux/kernel.h> | |
37 | #include <scsi/scsi.h> | |
38 | #include <scsi/scsi_host.h> | |
39 | #include <scsi/scsi_eh.h> | |
40 | #include <scsi/scsi_device.h> | |
41 | #include <scsi/scsi_cmnd.h> | |
42 | ||
43 | #include <linux/libata.h> | |
44 | ||
45 | #include "libata.h" | |
46 | ||
47 | /** | |
48 | * ata_scsi_timed_out - SCSI layer time out callback | |
49 | * @cmd: timed out SCSI command | |
50 | * | |
51 | * Handles SCSI layer timeout. We race with normal completion of | |
52 | * the qc for @cmd. If the qc is already gone, we lose and let | |
53 | * the scsi command finish (EH_HANDLED). Otherwise, the qc has | |
54 | * timed out and EH should be invoked. Prevent ata_qc_complete() | |
55 | * from finishing it by setting EH_SCHEDULED and return | |
56 | * EH_NOT_HANDLED. | |
57 | * | |
58 | * LOCKING: | |
59 | * Called from timer context | |
60 | * | |
61 | * RETURNS: | |
62 | * EH_HANDLED or EH_NOT_HANDLED | |
63 | */ | |
64 | enum scsi_eh_timer_return ata_scsi_timed_out(struct scsi_cmnd *cmd) | |
65 | { | |
66 | struct Scsi_Host *host = cmd->device->host; | |
35bb94b1 | 67 | struct ata_port *ap = ata_shost_to_port(host); |
ece1d636 TH |
68 | unsigned long flags; |
69 | struct ata_queued_cmd *qc; | |
70 | enum scsi_eh_timer_return ret = EH_HANDLED; | |
71 | ||
72 | DPRINTK("ENTER\n"); | |
73 | ||
74 | spin_lock_irqsave(&ap->host_set->lock, flags); | |
75 | qc = ata_qc_from_tag(ap, ap->active_tag); | |
76 | if (qc) { | |
77 | WARN_ON(qc->scsicmd != cmd); | |
78 | qc->flags |= ATA_QCFLAG_EH_SCHEDULED; | |
79 | qc->err_mask |= AC_ERR_TIMEOUT; | |
80 | ret = EH_NOT_HANDLED; | |
81 | } | |
82 | spin_unlock_irqrestore(&ap->host_set->lock, flags); | |
83 | ||
84 | DPRINTK("EXIT, ret=%d\n", ret); | |
85 | return ret; | |
86 | } | |
87 | ||
88 | /** | |
89 | * ata_scsi_error - SCSI layer error handler callback | |
90 | * @host: SCSI host on which error occurred | |
91 | * | |
92 | * Handles SCSI-layer-thrown error events. | |
93 | * | |
94 | * LOCKING: | |
95 | * Inherited from SCSI layer (none, can sleep) | |
96 | * | |
97 | * RETURNS: | |
98 | * Zero. | |
99 | */ | |
381544bb | 100 | void ata_scsi_error(struct Scsi_Host *host) |
ece1d636 | 101 | { |
35bb94b1 | 102 | struct ata_port *ap = ata_shost_to_port(host); |
ece1d636 TH |
103 | |
104 | DPRINTK("ENTER\n"); | |
105 | ||
106 | /* synchronize with IRQ handler and port task */ | |
107 | spin_unlock_wait(&ap->host_set->lock); | |
108 | ata_port_flush_task(ap); | |
109 | ||
110 | WARN_ON(ata_qc_from_tag(ap, ap->active_tag) == NULL); | |
111 | ||
112 | ap->ops->eng_timeout(ap); | |
113 | ||
114 | WARN_ON(host->host_failed || !list_empty(&host->eh_cmd_q)); | |
115 | ||
116 | scsi_eh_flush_done_q(&ap->eh_done_q); | |
117 | ||
118 | DPRINTK("EXIT\n"); | |
ece1d636 TH |
119 | } |
120 | ||
121 | /** | |
122 | * ata_qc_timeout - Handle timeout of queued command | |
123 | * @qc: Command that timed out | |
124 | * | |
125 | * Some part of the kernel (currently, only the SCSI layer) | |
126 | * has noticed that the active command on port @ap has not | |
127 | * completed after a specified length of time. Handle this | |
128 | * condition by disabling DMA (if necessary) and completing | |
129 | * transactions, with error if necessary. | |
130 | * | |
131 | * This also handles the case of the "lost interrupt", where | |
132 | * for some reason (possibly hardware bug, possibly driver bug) | |
133 | * an interrupt was not delivered to the driver, even though the | |
134 | * transaction completed successfully. | |
135 | * | |
136 | * LOCKING: | |
137 | * Inherited from SCSI layer (none, can sleep) | |
138 | */ | |
139 | static void ata_qc_timeout(struct ata_queued_cmd *qc) | |
140 | { | |
141 | struct ata_port *ap = qc->ap; | |
142 | struct ata_host_set *host_set = ap->host_set; | |
143 | u8 host_stat = 0, drv_stat; | |
144 | unsigned long flags; | |
145 | ||
146 | DPRINTK("ENTER\n"); | |
147 | ||
148 | ap->hsm_task_state = HSM_ST_IDLE; | |
149 | ||
150 | spin_lock_irqsave(&host_set->lock, flags); | |
151 | ||
152 | switch (qc->tf.protocol) { | |
153 | ||
154 | case ATA_PROT_DMA: | |
155 | case ATA_PROT_ATAPI_DMA: | |
156 | host_stat = ap->ops->bmdma_status(ap); | |
157 | ||
158 | /* before we do anything else, clear DMA-Start bit */ | |
159 | ap->ops->bmdma_stop(qc); | |
160 | ||
161 | /* fall through */ | |
162 | ||
163 | default: | |
164 | ata_altstatus(ap); | |
165 | drv_stat = ata_chk_status(ap); | |
166 | ||
167 | /* ack bmdma irq events */ | |
168 | ap->ops->irq_clear(ap); | |
169 | ||
f15a1daf TH |
170 | ata_dev_printk(qc->dev, KERN_ERR, "command 0x%x timeout, " |
171 | "stat 0x%x host_stat 0x%x\n", | |
172 | qc->tf.command, drv_stat, host_stat); | |
ece1d636 TH |
173 | |
174 | /* complete taskfile transaction */ | |
175 | qc->err_mask |= ac_err_mask(drv_stat); | |
176 | break; | |
177 | } | |
178 | ||
179 | spin_unlock_irqrestore(&host_set->lock, flags); | |
180 | ||
181 | ata_eh_qc_complete(qc); | |
182 | ||
183 | DPRINTK("EXIT\n"); | |
184 | } | |
185 | ||
186 | /** | |
187 | * ata_eng_timeout - Handle timeout of queued command | |
188 | * @ap: Port on which timed-out command is active | |
189 | * | |
190 | * Some part of the kernel (currently, only the SCSI layer) | |
191 | * has noticed that the active command on port @ap has not | |
192 | * completed after a specified length of time. Handle this | |
193 | * condition by disabling DMA (if necessary) and completing | |
194 | * transactions, with error if necessary. | |
195 | * | |
196 | * This also handles the case of the "lost interrupt", where | |
197 | * for some reason (possibly hardware bug, possibly driver bug) | |
198 | * an interrupt was not delivered to the driver, even though the | |
199 | * transaction completed successfully. | |
200 | * | |
201 | * LOCKING: | |
202 | * Inherited from SCSI layer (none, can sleep) | |
203 | */ | |
204 | void ata_eng_timeout(struct ata_port *ap) | |
205 | { | |
206 | DPRINTK("ENTER\n"); | |
207 | ||
208 | ata_qc_timeout(ata_qc_from_tag(ap, ap->active_tag)); | |
209 | ||
210 | DPRINTK("EXIT\n"); | |
211 | } | |
212 | ||
f686bcb8 TH |
213 | /** |
214 | * ata_qc_schedule_eh - schedule qc for error handling | |
215 | * @qc: command to schedule error handling for | |
216 | * | |
217 | * Schedule error handling for @qc. EH will kick in as soon as | |
218 | * other commands are drained. | |
219 | * | |
220 | * LOCKING: | |
221 | * spin_lock_irqsave(host_set lock) | |
222 | */ | |
223 | void ata_qc_schedule_eh(struct ata_queued_cmd *qc) | |
224 | { | |
225 | struct ata_port *ap = qc->ap; | |
226 | ||
227 | WARN_ON(!ap->ops->error_handler); | |
228 | ||
229 | qc->flags |= ATA_QCFLAG_FAILED; | |
230 | qc->ap->flags |= ATA_FLAG_EH_PENDING; | |
231 | ||
232 | /* The following will fail if timeout has already expired. | |
233 | * ata_scsi_error() takes care of such scmds on EH entry. | |
234 | * Note that ATA_QCFLAG_FAILED is unconditionally set after | |
235 | * this function completes. | |
236 | */ | |
237 | scsi_req_abort_cmd(qc->scsicmd); | |
238 | } | |
239 | ||
7b70fc03 TH |
240 | /** |
241 | * ata_port_schedule_eh - schedule error handling without a qc | |
242 | * @ap: ATA port to schedule EH for | |
243 | * | |
244 | * Schedule error handling for @ap. EH will kick in as soon as | |
245 | * all commands are drained. | |
246 | * | |
247 | * LOCKING: | |
248 | * spin_lock_irqsave(host_set lock) | |
249 | */ | |
250 | void ata_port_schedule_eh(struct ata_port *ap) | |
251 | { | |
252 | WARN_ON(!ap->ops->error_handler); | |
253 | ||
254 | ap->flags |= ATA_FLAG_EH_PENDING; | |
255 | ata_schedule_scsi_eh(ap->host); | |
256 | ||
257 | DPRINTK("port EH scheduled\n"); | |
258 | } | |
259 | ||
260 | /** | |
261 | * ata_port_abort - abort all qc's on the port | |
262 | * @ap: ATA port to abort qc's for | |
263 | * | |
264 | * Abort all active qc's of @ap and schedule EH. | |
265 | * | |
266 | * LOCKING: | |
267 | * spin_lock_irqsave(host_set lock) | |
268 | * | |
269 | * RETURNS: | |
270 | * Number of aborted qc's. | |
271 | */ | |
272 | int ata_port_abort(struct ata_port *ap) | |
273 | { | |
274 | int tag, nr_aborted = 0; | |
275 | ||
276 | WARN_ON(!ap->ops->error_handler); | |
277 | ||
278 | for (tag = 0; tag < ATA_MAX_QUEUE; tag++) { | |
279 | struct ata_queued_cmd *qc = ata_qc_from_tag(ap, tag); | |
280 | ||
281 | if (qc) { | |
282 | qc->flags |= ATA_QCFLAG_FAILED; | |
283 | ata_qc_complete(qc); | |
284 | nr_aborted++; | |
285 | } | |
286 | } | |
287 | ||
288 | if (!nr_aborted) | |
289 | ata_port_schedule_eh(ap); | |
290 | ||
291 | return nr_aborted; | |
292 | } | |
293 | ||
e3180499 TH |
294 | /** |
295 | * __ata_port_freeze - freeze port | |
296 | * @ap: ATA port to freeze | |
297 | * | |
298 | * This function is called when HSM violation or some other | |
299 | * condition disrupts normal operation of the port. Frozen port | |
300 | * is not allowed to perform any operation until the port is | |
301 | * thawed, which usually follows a successful reset. | |
302 | * | |
303 | * ap->ops->freeze() callback can be used for freezing the port | |
304 | * hardware-wise (e.g. mask interrupt and stop DMA engine). If a | |
305 | * port cannot be frozen hardware-wise, the interrupt handler | |
306 | * must ack and clear interrupts unconditionally while the port | |
307 | * is frozen. | |
308 | * | |
309 | * LOCKING: | |
310 | * spin_lock_irqsave(host_set lock) | |
311 | */ | |
312 | static void __ata_port_freeze(struct ata_port *ap) | |
313 | { | |
314 | WARN_ON(!ap->ops->error_handler); | |
315 | ||
316 | if (ap->ops->freeze) | |
317 | ap->ops->freeze(ap); | |
318 | ||
319 | ap->flags |= ATA_FLAG_FROZEN; | |
320 | ||
321 | DPRINTK("ata%u port frozen\n", ap->id); | |
322 | } | |
323 | ||
324 | /** | |
325 | * ata_port_freeze - abort & freeze port | |
326 | * @ap: ATA port to freeze | |
327 | * | |
328 | * Abort and freeze @ap. | |
329 | * | |
330 | * LOCKING: | |
331 | * spin_lock_irqsave(host_set lock) | |
332 | * | |
333 | * RETURNS: | |
334 | * Number of aborted commands. | |
335 | */ | |
336 | int ata_port_freeze(struct ata_port *ap) | |
337 | { | |
338 | int nr_aborted; | |
339 | ||
340 | WARN_ON(!ap->ops->error_handler); | |
341 | ||
342 | nr_aborted = ata_port_abort(ap); | |
343 | __ata_port_freeze(ap); | |
344 | ||
345 | return nr_aborted; | |
346 | } | |
347 | ||
348 | /** | |
349 | * ata_eh_freeze_port - EH helper to freeze port | |
350 | * @ap: ATA port to freeze | |
351 | * | |
352 | * Freeze @ap. | |
353 | * | |
354 | * LOCKING: | |
355 | * None. | |
356 | */ | |
357 | void ata_eh_freeze_port(struct ata_port *ap) | |
358 | { | |
359 | unsigned long flags; | |
360 | ||
361 | if (!ap->ops->error_handler) | |
362 | return; | |
363 | ||
364 | spin_lock_irqsave(&ap->host_set->lock, flags); | |
365 | __ata_port_freeze(ap); | |
366 | spin_unlock_irqrestore(&ap->host_set->lock, flags); | |
367 | } | |
368 | ||
369 | /** | |
370 | * ata_port_thaw_port - EH helper to thaw port | |
371 | * @ap: ATA port to thaw | |
372 | * | |
373 | * Thaw frozen port @ap. | |
374 | * | |
375 | * LOCKING: | |
376 | * None. | |
377 | */ | |
378 | void ata_eh_thaw_port(struct ata_port *ap) | |
379 | { | |
380 | unsigned long flags; | |
381 | ||
382 | if (!ap->ops->error_handler) | |
383 | return; | |
384 | ||
385 | spin_lock_irqsave(&ap->host_set->lock, flags); | |
386 | ||
387 | ap->flags &= ~ATA_FLAG_FROZEN; | |
388 | ||
389 | if (ap->ops->thaw) | |
390 | ap->ops->thaw(ap); | |
391 | ||
392 | spin_unlock_irqrestore(&ap->host_set->lock, flags); | |
393 | ||
394 | DPRINTK("ata%u port thawed\n", ap->id); | |
395 | } | |
396 | ||
ece1d636 TH |
397 | static void ata_eh_scsidone(struct scsi_cmnd *scmd) |
398 | { | |
399 | /* nada */ | |
400 | } | |
401 | ||
402 | static void __ata_eh_qc_complete(struct ata_queued_cmd *qc) | |
403 | { | |
404 | struct ata_port *ap = qc->ap; | |
405 | struct scsi_cmnd *scmd = qc->scsicmd; | |
406 | unsigned long flags; | |
407 | ||
408 | spin_lock_irqsave(&ap->host_set->lock, flags); | |
409 | qc->scsidone = ata_eh_scsidone; | |
410 | __ata_qc_complete(qc); | |
411 | WARN_ON(ata_tag_valid(qc->tag)); | |
412 | spin_unlock_irqrestore(&ap->host_set->lock, flags); | |
413 | ||
414 | scsi_eh_finish_cmd(scmd, &ap->eh_done_q); | |
415 | } | |
416 | ||
417 | /** | |
418 | * ata_eh_qc_complete - Complete an active ATA command from EH | |
419 | * @qc: Command to complete | |
420 | * | |
421 | * Indicate to the mid and upper layers that an ATA command has | |
422 | * completed. To be used from EH. | |
423 | */ | |
424 | void ata_eh_qc_complete(struct ata_queued_cmd *qc) | |
425 | { | |
426 | struct scsi_cmnd *scmd = qc->scsicmd; | |
427 | scmd->retries = scmd->allowed; | |
428 | __ata_eh_qc_complete(qc); | |
429 | } | |
430 | ||
431 | /** | |
432 | * ata_eh_qc_retry - Tell midlayer to retry an ATA command after EH | |
433 | * @qc: Command to retry | |
434 | * | |
435 | * Indicate to the mid and upper layers that an ATA command | |
436 | * should be retried. To be used from EH. | |
437 | * | |
438 | * SCSI midlayer limits the number of retries to scmd->allowed. | |
439 | * scmd->retries is decremented for commands which get retried | |
440 | * due to unrelated failures (qc->err_mask is zero). | |
441 | */ | |
442 | void ata_eh_qc_retry(struct ata_queued_cmd *qc) | |
443 | { | |
444 | struct scsi_cmnd *scmd = qc->scsicmd; | |
445 | if (!qc->err_mask && scmd->retries) | |
446 | scmd->retries--; | |
447 | __ata_eh_qc_complete(qc); | |
448 | } |