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1da177e4 LT |
1 | /* |
2 | * IDE I/O functions | |
3 | * | |
4 | * Basic PIO and command management functionality. | |
5 | * | |
6 | * This code was split off from ide.c. See ide.c for history and original | |
7 | * copyrights. | |
8 | * | |
9 | * This program is free software; you can redistribute it and/or modify it | |
10 | * under the terms of the GNU General Public License as published by the | |
11 | * Free Software Foundation; either version 2, or (at your option) any | |
12 | * later version. | |
13 | * | |
14 | * This program is distributed in the hope that it will be useful, but | |
15 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
17 | * General Public License for more details. | |
18 | * | |
19 | * For the avoidance of doubt the "preferred form" of this code is one which | |
20 | * is in an open non patent encumbered format. Where cryptographic key signing | |
21 | * forms part of the process of creating an executable the information | |
22 | * including keys needed to generate an equivalently functional executable | |
23 | * are deemed to be part of the source code. | |
24 | */ | |
25 | ||
26 | ||
27 | #include <linux/config.h> | |
28 | #include <linux/module.h> | |
29 | #include <linux/types.h> | |
30 | #include <linux/string.h> | |
31 | #include <linux/kernel.h> | |
32 | #include <linux/timer.h> | |
33 | #include <linux/mm.h> | |
34 | #include <linux/interrupt.h> | |
35 | #include <linux/major.h> | |
36 | #include <linux/errno.h> | |
37 | #include <linux/genhd.h> | |
38 | #include <linux/blkpg.h> | |
39 | #include <linux/slab.h> | |
40 | #include <linux/init.h> | |
41 | #include <linux/pci.h> | |
42 | #include <linux/delay.h> | |
43 | #include <linux/ide.h> | |
44 | #include <linux/completion.h> | |
45 | #include <linux/reboot.h> | |
46 | #include <linux/cdrom.h> | |
47 | #include <linux/seq_file.h> | |
48 | #include <linux/device.h> | |
49 | #include <linux/kmod.h> | |
50 | #include <linux/scatterlist.h> | |
51 | ||
52 | #include <asm/byteorder.h> | |
53 | #include <asm/irq.h> | |
54 | #include <asm/uaccess.h> | |
55 | #include <asm/io.h> | |
56 | #include <asm/bitops.h> | |
57 | ||
58 | int __ide_end_request(ide_drive_t *drive, struct request *rq, int uptodate, | |
59 | int nr_sectors) | |
60 | { | |
61 | int ret = 1; | |
62 | ||
63 | BUG_ON(!(rq->flags & REQ_STARTED)); | |
64 | ||
65 | /* | |
66 | * if failfast is set on a request, override number of sectors and | |
67 | * complete the whole request right now | |
68 | */ | |
69 | if (blk_noretry_request(rq) && end_io_error(uptodate)) | |
70 | nr_sectors = rq->hard_nr_sectors; | |
71 | ||
72 | if (!blk_fs_request(rq) && end_io_error(uptodate) && !rq->errors) | |
73 | rq->errors = -EIO; | |
74 | ||
75 | /* | |
76 | * decide whether to reenable DMA -- 3 is a random magic for now, | |
77 | * if we DMA timeout more than 3 times, just stay in PIO | |
78 | */ | |
79 | if (drive->state == DMA_PIO_RETRY && drive->retry_pio <= 3) { | |
80 | drive->state = 0; | |
81 | HWGROUP(drive)->hwif->ide_dma_on(drive); | |
82 | } | |
83 | ||
ba027def JA |
84 | if (!end_that_request_first(rq, uptodate, nr_sectors)) { |
85 | add_disk_randomness(rq->rq_disk); | |
1da177e4 LT |
86 | blkdev_dequeue_request(rq); |
87 | HWGROUP(drive)->rq = NULL; | |
ba027def | 88 | end_that_request_last(rq, uptodate); |
1da177e4 LT |
89 | ret = 0; |
90 | } | |
8672d571 | 91 | |
1da177e4 LT |
92 | return ret; |
93 | } | |
94 | EXPORT_SYMBOL(__ide_end_request); | |
95 | ||
96 | /** | |
97 | * ide_end_request - complete an IDE I/O | |
98 | * @drive: IDE device for the I/O | |
99 | * @uptodate: | |
100 | * @nr_sectors: number of sectors completed | |
101 | * | |
102 | * This is our end_request wrapper function. We complete the I/O | |
103 | * update random number input and dequeue the request, which if | |
104 | * it was tagged may be out of order. | |
105 | */ | |
106 | ||
107 | int ide_end_request (ide_drive_t *drive, int uptodate, int nr_sectors) | |
108 | { | |
109 | struct request *rq; | |
110 | unsigned long flags; | |
111 | int ret = 1; | |
112 | ||
8672d571 JA |
113 | /* |
114 | * room for locking improvements here, the calls below don't | |
115 | * need the queue lock held at all | |
116 | */ | |
1da177e4 LT |
117 | spin_lock_irqsave(&ide_lock, flags); |
118 | rq = HWGROUP(drive)->rq; | |
119 | ||
120 | if (!nr_sectors) | |
121 | nr_sectors = rq->hard_cur_sectors; | |
122 | ||
3e087b57 | 123 | ret = __ide_end_request(drive, rq, uptodate, nr_sectors); |
1da177e4 LT |
124 | |
125 | spin_unlock_irqrestore(&ide_lock, flags); | |
126 | return ret; | |
127 | } | |
128 | EXPORT_SYMBOL(ide_end_request); | |
129 | ||
130 | /* | |
131 | * Power Management state machine. This one is rather trivial for now, | |
132 | * we should probably add more, like switching back to PIO on suspend | |
133 | * to help some BIOSes, re-do the door locking on resume, etc... | |
134 | */ | |
135 | ||
136 | enum { | |
137 | ide_pm_flush_cache = ide_pm_state_start_suspend, | |
138 | idedisk_pm_standby, | |
139 | ||
140 | idedisk_pm_idle = ide_pm_state_start_resume, | |
141 | ide_pm_restore_dma, | |
142 | }; | |
143 | ||
144 | static void ide_complete_power_step(ide_drive_t *drive, struct request *rq, u8 stat, u8 error) | |
145 | { | |
146 | if (drive->media != ide_disk) | |
147 | return; | |
148 | ||
149 | switch (rq->pm->pm_step) { | |
150 | case ide_pm_flush_cache: /* Suspend step 1 (flush cache) complete */ | |
46dacba5 | 151 | if (rq->pm->pm_state == PM_EVENT_FREEZE) |
1da177e4 LT |
152 | rq->pm->pm_step = ide_pm_state_completed; |
153 | else | |
154 | rq->pm->pm_step = idedisk_pm_standby; | |
155 | break; | |
156 | case idedisk_pm_standby: /* Suspend step 2 (standby) complete */ | |
157 | rq->pm->pm_step = ide_pm_state_completed; | |
158 | break; | |
159 | case idedisk_pm_idle: /* Resume step 1 (idle) complete */ | |
160 | rq->pm->pm_step = ide_pm_restore_dma; | |
161 | break; | |
162 | } | |
163 | } | |
164 | ||
165 | static ide_startstop_t ide_start_power_step(ide_drive_t *drive, struct request *rq) | |
166 | { | |
167 | ide_task_t *args = rq->special; | |
168 | ||
169 | memset(args, 0, sizeof(*args)); | |
170 | ||
171 | if (drive->media != ide_disk) { | |
172 | /* skip idedisk_pm_idle for ATAPI devices */ | |
173 | if (rq->pm->pm_step == idedisk_pm_idle) | |
174 | rq->pm->pm_step = ide_pm_restore_dma; | |
175 | } | |
176 | ||
177 | switch (rq->pm->pm_step) { | |
178 | case ide_pm_flush_cache: /* Suspend step 1 (flush cache) */ | |
179 | if (drive->media != ide_disk) | |
180 | break; | |
181 | /* Not supported? Switch to next step now. */ | |
182 | if (!drive->wcache || !ide_id_has_flush_cache(drive->id)) { | |
183 | ide_complete_power_step(drive, rq, 0, 0); | |
184 | return ide_stopped; | |
185 | } | |
186 | if (ide_id_has_flush_cache_ext(drive->id)) | |
187 | args->tfRegister[IDE_COMMAND_OFFSET] = WIN_FLUSH_CACHE_EXT; | |
188 | else | |
189 | args->tfRegister[IDE_COMMAND_OFFSET] = WIN_FLUSH_CACHE; | |
190 | args->command_type = IDE_DRIVE_TASK_NO_DATA; | |
191 | args->handler = &task_no_data_intr; | |
192 | return do_rw_taskfile(drive, args); | |
193 | ||
194 | case idedisk_pm_standby: /* Suspend step 2 (standby) */ | |
195 | args->tfRegister[IDE_COMMAND_OFFSET] = WIN_STANDBYNOW1; | |
196 | args->command_type = IDE_DRIVE_TASK_NO_DATA; | |
197 | args->handler = &task_no_data_intr; | |
198 | return do_rw_taskfile(drive, args); | |
199 | ||
200 | case idedisk_pm_idle: /* Resume step 1 (idle) */ | |
201 | args->tfRegister[IDE_COMMAND_OFFSET] = WIN_IDLEIMMEDIATE; | |
202 | args->command_type = IDE_DRIVE_TASK_NO_DATA; | |
203 | args->handler = task_no_data_intr; | |
204 | return do_rw_taskfile(drive, args); | |
205 | ||
206 | case ide_pm_restore_dma: /* Resume step 2 (restore DMA) */ | |
207 | /* | |
208 | * Right now, all we do is call hwif->ide_dma_check(drive), | |
209 | * we could be smarter and check for current xfer_speed | |
210 | * in struct drive etc... | |
211 | */ | |
212 | if ((drive->id->capability & 1) == 0) | |
213 | break; | |
214 | if (drive->hwif->ide_dma_check == NULL) | |
215 | break; | |
216 | drive->hwif->ide_dma_check(drive); | |
217 | break; | |
218 | } | |
219 | rq->pm->pm_step = ide_pm_state_completed; | |
220 | return ide_stopped; | |
221 | } | |
222 | ||
223 | /** | |
224 | * ide_complete_pm_request - end the current Power Management request | |
225 | * @drive: target drive | |
226 | * @rq: request | |
227 | * | |
228 | * This function cleans up the current PM request and stops the queue | |
229 | * if necessary. | |
230 | */ | |
231 | static void ide_complete_pm_request (ide_drive_t *drive, struct request *rq) | |
232 | { | |
233 | unsigned long flags; | |
234 | ||
235 | #ifdef DEBUG_PM | |
236 | printk("%s: completing PM request, %s\n", drive->name, | |
237 | blk_pm_suspend_request(rq) ? "suspend" : "resume"); | |
238 | #endif | |
239 | spin_lock_irqsave(&ide_lock, flags); | |
240 | if (blk_pm_suspend_request(rq)) { | |
241 | blk_stop_queue(drive->queue); | |
242 | } else { | |
243 | drive->blocked = 0; | |
244 | blk_start_queue(drive->queue); | |
245 | } | |
246 | blkdev_dequeue_request(rq); | |
247 | HWGROUP(drive)->rq = NULL; | |
8ffdc655 | 248 | end_that_request_last(rq, 1); |
1da177e4 LT |
249 | spin_unlock_irqrestore(&ide_lock, flags); |
250 | } | |
251 | ||
252 | /* | |
253 | * FIXME: probably move this somewhere else, name is bad too :) | |
254 | */ | |
255 | u64 ide_get_error_location(ide_drive_t *drive, char *args) | |
256 | { | |
257 | u32 high, low; | |
258 | u8 hcyl, lcyl, sect; | |
259 | u64 sector; | |
260 | ||
261 | high = 0; | |
262 | hcyl = args[5]; | |
263 | lcyl = args[4]; | |
264 | sect = args[3]; | |
265 | ||
266 | if (ide_id_has_flush_cache_ext(drive->id)) { | |
267 | low = (hcyl << 16) | (lcyl << 8) | sect; | |
268 | HWIF(drive)->OUTB(drive->ctl|0x80, IDE_CONTROL_REG); | |
269 | high = ide_read_24(drive); | |
270 | } else { | |
271 | u8 cur = HWIF(drive)->INB(IDE_SELECT_REG); | |
272 | if (cur & 0x40) { | |
273 | high = cur & 0xf; | |
274 | low = (hcyl << 16) | (lcyl << 8) | sect; | |
275 | } else { | |
276 | low = hcyl * drive->head * drive->sect; | |
277 | low += lcyl * drive->sect; | |
278 | low += sect - 1; | |
279 | } | |
280 | } | |
281 | ||
282 | sector = ((u64) high << 24) | low; | |
283 | return sector; | |
284 | } | |
285 | EXPORT_SYMBOL(ide_get_error_location); | |
286 | ||
287 | /** | |
288 | * ide_end_drive_cmd - end an explicit drive command | |
289 | * @drive: command | |
290 | * @stat: status bits | |
291 | * @err: error bits | |
292 | * | |
293 | * Clean up after success/failure of an explicit drive command. | |
294 | * These get thrown onto the queue so they are synchronized with | |
295 | * real I/O operations on the drive. | |
296 | * | |
297 | * In LBA48 mode we have to read the register set twice to get | |
298 | * all the extra information out. | |
299 | */ | |
300 | ||
301 | void ide_end_drive_cmd (ide_drive_t *drive, u8 stat, u8 err) | |
302 | { | |
303 | ide_hwif_t *hwif = HWIF(drive); | |
304 | unsigned long flags; | |
305 | struct request *rq; | |
306 | ||
307 | spin_lock_irqsave(&ide_lock, flags); | |
308 | rq = HWGROUP(drive)->rq; | |
309 | spin_unlock_irqrestore(&ide_lock, flags); | |
310 | ||
311 | if (rq->flags & REQ_DRIVE_CMD) { | |
312 | u8 *args = (u8 *) rq->buffer; | |
313 | if (rq->errors == 0) | |
314 | rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT); | |
315 | ||
316 | if (args) { | |
317 | args[0] = stat; | |
318 | args[1] = err; | |
319 | args[2] = hwif->INB(IDE_NSECTOR_REG); | |
320 | } | |
321 | } else if (rq->flags & REQ_DRIVE_TASK) { | |
322 | u8 *args = (u8 *) rq->buffer; | |
323 | if (rq->errors == 0) | |
324 | rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT); | |
325 | ||
326 | if (args) { | |
327 | args[0] = stat; | |
328 | args[1] = err; | |
329 | args[2] = hwif->INB(IDE_NSECTOR_REG); | |
330 | args[3] = hwif->INB(IDE_SECTOR_REG); | |
331 | args[4] = hwif->INB(IDE_LCYL_REG); | |
332 | args[5] = hwif->INB(IDE_HCYL_REG); | |
333 | args[6] = hwif->INB(IDE_SELECT_REG); | |
334 | } | |
335 | } else if (rq->flags & REQ_DRIVE_TASKFILE) { | |
336 | ide_task_t *args = (ide_task_t *) rq->special; | |
337 | if (rq->errors == 0) | |
338 | rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT); | |
339 | ||
340 | if (args) { | |
341 | if (args->tf_in_flags.b.data) { | |
342 | u16 data = hwif->INW(IDE_DATA_REG); | |
343 | args->tfRegister[IDE_DATA_OFFSET] = (data) & 0xFF; | |
344 | args->hobRegister[IDE_DATA_OFFSET] = (data >> 8) & 0xFF; | |
345 | } | |
346 | args->tfRegister[IDE_ERROR_OFFSET] = err; | |
347 | /* be sure we're looking at the low order bits */ | |
348 | hwif->OUTB(drive->ctl & ~0x80, IDE_CONTROL_REG); | |
349 | args->tfRegister[IDE_NSECTOR_OFFSET] = hwif->INB(IDE_NSECTOR_REG); | |
350 | args->tfRegister[IDE_SECTOR_OFFSET] = hwif->INB(IDE_SECTOR_REG); | |
351 | args->tfRegister[IDE_LCYL_OFFSET] = hwif->INB(IDE_LCYL_REG); | |
352 | args->tfRegister[IDE_HCYL_OFFSET] = hwif->INB(IDE_HCYL_REG); | |
353 | args->tfRegister[IDE_SELECT_OFFSET] = hwif->INB(IDE_SELECT_REG); | |
354 | args->tfRegister[IDE_STATUS_OFFSET] = stat; | |
355 | ||
356 | if (drive->addressing == 1) { | |
357 | hwif->OUTB(drive->ctl|0x80, IDE_CONTROL_REG); | |
358 | args->hobRegister[IDE_FEATURE_OFFSET] = hwif->INB(IDE_FEATURE_REG); | |
359 | args->hobRegister[IDE_NSECTOR_OFFSET] = hwif->INB(IDE_NSECTOR_REG); | |
360 | args->hobRegister[IDE_SECTOR_OFFSET] = hwif->INB(IDE_SECTOR_REG); | |
361 | args->hobRegister[IDE_LCYL_OFFSET] = hwif->INB(IDE_LCYL_REG); | |
362 | args->hobRegister[IDE_HCYL_OFFSET] = hwif->INB(IDE_HCYL_REG); | |
363 | } | |
364 | } | |
365 | } else if (blk_pm_request(rq)) { | |
366 | #ifdef DEBUG_PM | |
367 | printk("%s: complete_power_step(step: %d, stat: %x, err: %x)\n", | |
368 | drive->name, rq->pm->pm_step, stat, err); | |
369 | #endif | |
370 | ide_complete_power_step(drive, rq, stat, err); | |
371 | if (rq->pm->pm_step == ide_pm_state_completed) | |
372 | ide_complete_pm_request(drive, rq); | |
373 | return; | |
374 | } | |
375 | ||
376 | spin_lock_irqsave(&ide_lock, flags); | |
377 | blkdev_dequeue_request(rq); | |
378 | HWGROUP(drive)->rq = NULL; | |
379 | rq->errors = err; | |
8ffdc655 | 380 | end_that_request_last(rq, !rq->errors); |
1da177e4 LT |
381 | spin_unlock_irqrestore(&ide_lock, flags); |
382 | } | |
383 | ||
384 | EXPORT_SYMBOL(ide_end_drive_cmd); | |
385 | ||
386 | /** | |
387 | * try_to_flush_leftover_data - flush junk | |
388 | * @drive: drive to flush | |
389 | * | |
390 | * try_to_flush_leftover_data() is invoked in response to a drive | |
391 | * unexpectedly having its DRQ_STAT bit set. As an alternative to | |
392 | * resetting the drive, this routine tries to clear the condition | |
393 | * by read a sector's worth of data from the drive. Of course, | |
394 | * this may not help if the drive is *waiting* for data from *us*. | |
395 | */ | |
396 | static void try_to_flush_leftover_data (ide_drive_t *drive) | |
397 | { | |
398 | int i = (drive->mult_count ? drive->mult_count : 1) * SECTOR_WORDS; | |
399 | ||
400 | if (drive->media != ide_disk) | |
401 | return; | |
402 | while (i > 0) { | |
403 | u32 buffer[16]; | |
404 | u32 wcount = (i > 16) ? 16 : i; | |
405 | ||
406 | i -= wcount; | |
407 | HWIF(drive)->ata_input_data(drive, buffer, wcount); | |
408 | } | |
409 | } | |
410 | ||
411 | static void ide_kill_rq(ide_drive_t *drive, struct request *rq) | |
412 | { | |
413 | if (rq->rq_disk) { | |
414 | ide_driver_t *drv; | |
415 | ||
416 | drv = *(ide_driver_t **)rq->rq_disk->private_data; | |
417 | drv->end_request(drive, 0, 0); | |
418 | } else | |
419 | ide_end_request(drive, 0, 0); | |
420 | } | |
421 | ||
422 | static ide_startstop_t ide_ata_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) | |
423 | { | |
424 | ide_hwif_t *hwif = drive->hwif; | |
425 | ||
426 | if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) { | |
427 | /* other bits are useless when BUSY */ | |
428 | rq->errors |= ERROR_RESET; | |
429 | } else if (stat & ERR_STAT) { | |
430 | /* err has different meaning on cdrom and tape */ | |
431 | if (err == ABRT_ERR) { | |
432 | if (drive->select.b.lba && | |
433 | /* some newer drives don't support WIN_SPECIFY */ | |
434 | hwif->INB(IDE_COMMAND_REG) == WIN_SPECIFY) | |
435 | return ide_stopped; | |
436 | } else if ((err & BAD_CRC) == BAD_CRC) { | |
437 | /* UDMA crc error, just retry the operation */ | |
438 | drive->crc_count++; | |
439 | } else if (err & (BBD_ERR | ECC_ERR)) { | |
440 | /* retries won't help these */ | |
441 | rq->errors = ERROR_MAX; | |
442 | } else if (err & TRK0_ERR) { | |
443 | /* help it find track zero */ | |
444 | rq->errors |= ERROR_RECAL; | |
445 | } | |
446 | } | |
447 | ||
448 | if ((stat & DRQ_STAT) && rq_data_dir(rq) == READ) | |
449 | try_to_flush_leftover_data(drive); | |
450 | ||
451 | if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT)) | |
452 | /* force an abort */ | |
453 | hwif->OUTB(WIN_IDLEIMMEDIATE, IDE_COMMAND_REG); | |
454 | ||
455 | if (rq->errors >= ERROR_MAX || blk_noretry_request(rq)) | |
456 | ide_kill_rq(drive, rq); | |
457 | else { | |
458 | if ((rq->errors & ERROR_RESET) == ERROR_RESET) { | |
459 | ++rq->errors; | |
460 | return ide_do_reset(drive); | |
461 | } | |
462 | if ((rq->errors & ERROR_RECAL) == ERROR_RECAL) | |
463 | drive->special.b.recalibrate = 1; | |
464 | ++rq->errors; | |
465 | } | |
466 | return ide_stopped; | |
467 | } | |
468 | ||
469 | static ide_startstop_t ide_atapi_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) | |
470 | { | |
471 | ide_hwif_t *hwif = drive->hwif; | |
472 | ||
473 | if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) { | |
474 | /* other bits are useless when BUSY */ | |
475 | rq->errors |= ERROR_RESET; | |
476 | } else { | |
477 | /* add decoding error stuff */ | |
478 | } | |
479 | ||
480 | if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT)) | |
481 | /* force an abort */ | |
482 | hwif->OUTB(WIN_IDLEIMMEDIATE, IDE_COMMAND_REG); | |
483 | ||
484 | if (rq->errors >= ERROR_MAX) { | |
485 | ide_kill_rq(drive, rq); | |
486 | } else { | |
487 | if ((rq->errors & ERROR_RESET) == ERROR_RESET) { | |
488 | ++rq->errors; | |
489 | return ide_do_reset(drive); | |
490 | } | |
491 | ++rq->errors; | |
492 | } | |
493 | ||
494 | return ide_stopped; | |
495 | } | |
496 | ||
497 | ide_startstop_t | |
498 | __ide_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) | |
499 | { | |
500 | if (drive->media == ide_disk) | |
501 | return ide_ata_error(drive, rq, stat, err); | |
502 | return ide_atapi_error(drive, rq, stat, err); | |
503 | } | |
504 | ||
505 | EXPORT_SYMBOL_GPL(__ide_error); | |
506 | ||
507 | /** | |
508 | * ide_error - handle an error on the IDE | |
509 | * @drive: drive the error occurred on | |
510 | * @msg: message to report | |
511 | * @stat: status bits | |
512 | * | |
513 | * ide_error() takes action based on the error returned by the drive. | |
514 | * For normal I/O that may well include retries. We deal with | |
515 | * both new-style (taskfile) and old style command handling here. | |
516 | * In the case of taskfile command handling there is work left to | |
517 | * do | |
518 | */ | |
519 | ||
520 | ide_startstop_t ide_error (ide_drive_t *drive, const char *msg, u8 stat) | |
521 | { | |
522 | struct request *rq; | |
523 | u8 err; | |
524 | ||
525 | err = ide_dump_status(drive, msg, stat); | |
526 | ||
527 | if ((rq = HWGROUP(drive)->rq) == NULL) | |
528 | return ide_stopped; | |
529 | ||
530 | /* retry only "normal" I/O: */ | |
531 | if (rq->flags & (REQ_DRIVE_CMD | REQ_DRIVE_TASK | REQ_DRIVE_TASKFILE)) { | |
532 | rq->errors = 1; | |
533 | ide_end_drive_cmd(drive, stat, err); | |
534 | return ide_stopped; | |
535 | } | |
536 | ||
537 | if (rq->rq_disk) { | |
538 | ide_driver_t *drv; | |
539 | ||
540 | drv = *(ide_driver_t **)rq->rq_disk->private_data; | |
541 | return drv->error(drive, rq, stat, err); | |
542 | } else | |
543 | return __ide_error(drive, rq, stat, err); | |
544 | } | |
545 | ||
546 | EXPORT_SYMBOL_GPL(ide_error); | |
547 | ||
548 | ide_startstop_t __ide_abort(ide_drive_t *drive, struct request *rq) | |
549 | { | |
550 | if (drive->media != ide_disk) | |
551 | rq->errors |= ERROR_RESET; | |
552 | ||
553 | ide_kill_rq(drive, rq); | |
554 | ||
555 | return ide_stopped; | |
556 | } | |
557 | ||
558 | EXPORT_SYMBOL_GPL(__ide_abort); | |
559 | ||
560 | /** | |
338cec32 | 561 | * ide_abort - abort pending IDE operations |
1da177e4 LT |
562 | * @drive: drive the error occurred on |
563 | * @msg: message to report | |
564 | * | |
565 | * ide_abort kills and cleans up when we are about to do a | |
566 | * host initiated reset on active commands. Longer term we | |
567 | * want handlers to have sensible abort handling themselves | |
568 | * | |
569 | * This differs fundamentally from ide_error because in | |
570 | * this case the command is doing just fine when we | |
571 | * blow it away. | |
572 | */ | |
573 | ||
574 | ide_startstop_t ide_abort(ide_drive_t *drive, const char *msg) | |
575 | { | |
576 | struct request *rq; | |
577 | ||
578 | if (drive == NULL || (rq = HWGROUP(drive)->rq) == NULL) | |
579 | return ide_stopped; | |
580 | ||
581 | /* retry only "normal" I/O: */ | |
582 | if (rq->flags & (REQ_DRIVE_CMD | REQ_DRIVE_TASK | REQ_DRIVE_TASKFILE)) { | |
583 | rq->errors = 1; | |
584 | ide_end_drive_cmd(drive, BUSY_STAT, 0); | |
585 | return ide_stopped; | |
586 | } | |
587 | ||
588 | if (rq->rq_disk) { | |
589 | ide_driver_t *drv; | |
590 | ||
591 | drv = *(ide_driver_t **)rq->rq_disk->private_data; | |
592 | return drv->abort(drive, rq); | |
593 | } else | |
594 | return __ide_abort(drive, rq); | |
595 | } | |
596 | ||
597 | /** | |
598 | * ide_cmd - issue a simple drive command | |
599 | * @drive: drive the command is for | |
600 | * @cmd: command byte | |
601 | * @nsect: sector byte | |
602 | * @handler: handler for the command completion | |
603 | * | |
604 | * Issue a simple drive command with interrupts. | |
605 | * The drive must be selected beforehand. | |
606 | */ | |
607 | ||
608 | static void ide_cmd (ide_drive_t *drive, u8 cmd, u8 nsect, | |
609 | ide_handler_t *handler) | |
610 | { | |
611 | ide_hwif_t *hwif = HWIF(drive); | |
612 | if (IDE_CONTROL_REG) | |
613 | hwif->OUTB(drive->ctl,IDE_CONTROL_REG); /* clear nIEN */ | |
614 | SELECT_MASK(drive,0); | |
615 | hwif->OUTB(nsect,IDE_NSECTOR_REG); | |
616 | ide_execute_command(drive, cmd, handler, WAIT_CMD, NULL); | |
617 | } | |
618 | ||
619 | /** | |
620 | * drive_cmd_intr - drive command completion interrupt | |
621 | * @drive: drive the completion interrupt occurred on | |
622 | * | |
623 | * drive_cmd_intr() is invoked on completion of a special DRIVE_CMD. | |
338cec32 | 624 | * We do any necessary data reading and then wait for the drive to |
1da177e4 LT |
625 | * go non busy. At that point we may read the error data and complete |
626 | * the request | |
627 | */ | |
628 | ||
629 | static ide_startstop_t drive_cmd_intr (ide_drive_t *drive) | |
630 | { | |
631 | struct request *rq = HWGROUP(drive)->rq; | |
632 | ide_hwif_t *hwif = HWIF(drive); | |
633 | u8 *args = (u8 *) rq->buffer; | |
634 | u8 stat = hwif->INB(IDE_STATUS_REG); | |
635 | int retries = 10; | |
636 | ||
637 | local_irq_enable(); | |
638 | if ((stat & DRQ_STAT) && args && args[3]) { | |
639 | u8 io_32bit = drive->io_32bit; | |
640 | drive->io_32bit = 0; | |
641 | hwif->ata_input_data(drive, &args[4], args[3] * SECTOR_WORDS); | |
642 | drive->io_32bit = io_32bit; | |
643 | while (((stat = hwif->INB(IDE_STATUS_REG)) & BUSY_STAT) && retries--) | |
644 | udelay(100); | |
645 | } | |
646 | ||
647 | if (!OK_STAT(stat, READY_STAT, BAD_STAT)) | |
648 | return ide_error(drive, "drive_cmd", stat); | |
649 | /* calls ide_end_drive_cmd */ | |
650 | ide_end_drive_cmd(drive, stat, hwif->INB(IDE_ERROR_REG)); | |
651 | return ide_stopped; | |
652 | } | |
653 | ||
654 | static void ide_init_specify_cmd(ide_drive_t *drive, ide_task_t *task) | |
655 | { | |
656 | task->tfRegister[IDE_NSECTOR_OFFSET] = drive->sect; | |
657 | task->tfRegister[IDE_SECTOR_OFFSET] = drive->sect; | |
658 | task->tfRegister[IDE_LCYL_OFFSET] = drive->cyl; | |
659 | task->tfRegister[IDE_HCYL_OFFSET] = drive->cyl>>8; | |
660 | task->tfRegister[IDE_SELECT_OFFSET] = ((drive->head-1)|drive->select.all)&0xBF; | |
661 | task->tfRegister[IDE_COMMAND_OFFSET] = WIN_SPECIFY; | |
662 | ||
663 | task->handler = &set_geometry_intr; | |
664 | } | |
665 | ||
666 | static void ide_init_restore_cmd(ide_drive_t *drive, ide_task_t *task) | |
667 | { | |
668 | task->tfRegister[IDE_NSECTOR_OFFSET] = drive->sect; | |
669 | task->tfRegister[IDE_COMMAND_OFFSET] = WIN_RESTORE; | |
670 | ||
671 | task->handler = &recal_intr; | |
672 | } | |
673 | ||
674 | static void ide_init_setmult_cmd(ide_drive_t *drive, ide_task_t *task) | |
675 | { | |
676 | task->tfRegister[IDE_NSECTOR_OFFSET] = drive->mult_req; | |
677 | task->tfRegister[IDE_COMMAND_OFFSET] = WIN_SETMULT; | |
678 | ||
679 | task->handler = &set_multmode_intr; | |
680 | } | |
681 | ||
682 | static ide_startstop_t ide_disk_special(ide_drive_t *drive) | |
683 | { | |
684 | special_t *s = &drive->special; | |
685 | ide_task_t args; | |
686 | ||
687 | memset(&args, 0, sizeof(ide_task_t)); | |
688 | args.command_type = IDE_DRIVE_TASK_NO_DATA; | |
689 | ||
690 | if (s->b.set_geometry) { | |
691 | s->b.set_geometry = 0; | |
692 | ide_init_specify_cmd(drive, &args); | |
693 | } else if (s->b.recalibrate) { | |
694 | s->b.recalibrate = 0; | |
695 | ide_init_restore_cmd(drive, &args); | |
696 | } else if (s->b.set_multmode) { | |
697 | s->b.set_multmode = 0; | |
698 | if (drive->mult_req > drive->id->max_multsect) | |
699 | drive->mult_req = drive->id->max_multsect; | |
700 | ide_init_setmult_cmd(drive, &args); | |
701 | } else if (s->all) { | |
702 | int special = s->all; | |
703 | s->all = 0; | |
704 | printk(KERN_ERR "%s: bad special flag: 0x%02x\n", drive->name, special); | |
705 | return ide_stopped; | |
706 | } | |
707 | ||
708 | do_rw_taskfile(drive, &args); | |
709 | ||
710 | return ide_started; | |
711 | } | |
712 | ||
713 | /** | |
714 | * do_special - issue some special commands | |
715 | * @drive: drive the command is for | |
716 | * | |
717 | * do_special() is used to issue WIN_SPECIFY, WIN_RESTORE, and WIN_SETMULT | |
718 | * commands to a drive. It used to do much more, but has been scaled | |
719 | * back. | |
720 | */ | |
721 | ||
722 | static ide_startstop_t do_special (ide_drive_t *drive) | |
723 | { | |
724 | special_t *s = &drive->special; | |
725 | ||
726 | #ifdef DEBUG | |
727 | printk("%s: do_special: 0x%02x\n", drive->name, s->all); | |
728 | #endif | |
729 | if (s->b.set_tune) { | |
730 | s->b.set_tune = 0; | |
731 | if (HWIF(drive)->tuneproc != NULL) | |
732 | HWIF(drive)->tuneproc(drive, drive->tune_req); | |
733 | return ide_stopped; | |
734 | } else { | |
735 | if (drive->media == ide_disk) | |
736 | return ide_disk_special(drive); | |
737 | ||
738 | s->all = 0; | |
739 | drive->mult_req = 0; | |
740 | return ide_stopped; | |
741 | } | |
742 | } | |
743 | ||
744 | void ide_map_sg(ide_drive_t *drive, struct request *rq) | |
745 | { | |
746 | ide_hwif_t *hwif = drive->hwif; | |
747 | struct scatterlist *sg = hwif->sg_table; | |
748 | ||
749 | if (hwif->sg_mapped) /* needed by ide-scsi */ | |
750 | return; | |
751 | ||
752 | if ((rq->flags & REQ_DRIVE_TASKFILE) == 0) { | |
753 | hwif->sg_nents = blk_rq_map_sg(drive->queue, rq, sg); | |
754 | } else { | |
755 | sg_init_one(sg, rq->buffer, rq->nr_sectors * SECTOR_SIZE); | |
756 | hwif->sg_nents = 1; | |
757 | } | |
758 | } | |
759 | ||
760 | EXPORT_SYMBOL_GPL(ide_map_sg); | |
761 | ||
762 | void ide_init_sg_cmd(ide_drive_t *drive, struct request *rq) | |
763 | { | |
764 | ide_hwif_t *hwif = drive->hwif; | |
765 | ||
766 | hwif->nsect = hwif->nleft = rq->nr_sectors; | |
767 | hwif->cursg = hwif->cursg_ofs = 0; | |
768 | } | |
769 | ||
770 | EXPORT_SYMBOL_GPL(ide_init_sg_cmd); | |
771 | ||
772 | /** | |
773 | * execute_drive_command - issue special drive command | |
338cec32 | 774 | * @drive: the drive to issue the command on |
1da177e4 LT |
775 | * @rq: the request structure holding the command |
776 | * | |
777 | * execute_drive_cmd() issues a special drive command, usually | |
778 | * initiated by ioctl() from the external hdparm program. The | |
779 | * command can be a drive command, drive task or taskfile | |
780 | * operation. Weirdly you can call it with NULL to wait for | |
781 | * all commands to finish. Don't do this as that is due to change | |
782 | */ | |
783 | ||
784 | static ide_startstop_t execute_drive_cmd (ide_drive_t *drive, | |
785 | struct request *rq) | |
786 | { | |
787 | ide_hwif_t *hwif = HWIF(drive); | |
788 | if (rq->flags & REQ_DRIVE_TASKFILE) { | |
789 | ide_task_t *args = rq->special; | |
790 | ||
791 | if (!args) | |
792 | goto done; | |
793 | ||
794 | hwif->data_phase = args->data_phase; | |
795 | ||
796 | switch (hwif->data_phase) { | |
797 | case TASKFILE_MULTI_OUT: | |
798 | case TASKFILE_OUT: | |
799 | case TASKFILE_MULTI_IN: | |
800 | case TASKFILE_IN: | |
801 | ide_init_sg_cmd(drive, rq); | |
802 | ide_map_sg(drive, rq); | |
803 | default: | |
804 | break; | |
805 | } | |
806 | ||
807 | if (args->tf_out_flags.all != 0) | |
808 | return flagged_taskfile(drive, args); | |
809 | return do_rw_taskfile(drive, args); | |
810 | } else if (rq->flags & REQ_DRIVE_TASK) { | |
811 | u8 *args = rq->buffer; | |
812 | u8 sel; | |
813 | ||
814 | if (!args) | |
815 | goto done; | |
816 | #ifdef DEBUG | |
817 | printk("%s: DRIVE_TASK_CMD ", drive->name); | |
818 | printk("cmd=0x%02x ", args[0]); | |
819 | printk("fr=0x%02x ", args[1]); | |
820 | printk("ns=0x%02x ", args[2]); | |
821 | printk("sc=0x%02x ", args[3]); | |
822 | printk("lcyl=0x%02x ", args[4]); | |
823 | printk("hcyl=0x%02x ", args[5]); | |
824 | printk("sel=0x%02x\n", args[6]); | |
825 | #endif | |
826 | hwif->OUTB(args[1], IDE_FEATURE_REG); | |
827 | hwif->OUTB(args[3], IDE_SECTOR_REG); | |
828 | hwif->OUTB(args[4], IDE_LCYL_REG); | |
829 | hwif->OUTB(args[5], IDE_HCYL_REG); | |
830 | sel = (args[6] & ~0x10); | |
831 | if (drive->select.b.unit) | |
832 | sel |= 0x10; | |
833 | hwif->OUTB(sel, IDE_SELECT_REG); | |
834 | ide_cmd(drive, args[0], args[2], &drive_cmd_intr); | |
835 | return ide_started; | |
836 | } else if (rq->flags & REQ_DRIVE_CMD) { | |
837 | u8 *args = rq->buffer; | |
838 | ||
839 | if (!args) | |
840 | goto done; | |
841 | #ifdef DEBUG | |
842 | printk("%s: DRIVE_CMD ", drive->name); | |
843 | printk("cmd=0x%02x ", args[0]); | |
844 | printk("sc=0x%02x ", args[1]); | |
845 | printk("fr=0x%02x ", args[2]); | |
846 | printk("xx=0x%02x\n", args[3]); | |
847 | #endif | |
848 | if (args[0] == WIN_SMART) { | |
849 | hwif->OUTB(0x4f, IDE_LCYL_REG); | |
850 | hwif->OUTB(0xc2, IDE_HCYL_REG); | |
851 | hwif->OUTB(args[2],IDE_FEATURE_REG); | |
852 | hwif->OUTB(args[1],IDE_SECTOR_REG); | |
853 | ide_cmd(drive, args[0], args[3], &drive_cmd_intr); | |
854 | return ide_started; | |
855 | } | |
856 | hwif->OUTB(args[2],IDE_FEATURE_REG); | |
857 | ide_cmd(drive, args[0], args[1], &drive_cmd_intr); | |
858 | return ide_started; | |
859 | } | |
860 | ||
861 | done: | |
862 | /* | |
863 | * NULL is actually a valid way of waiting for | |
864 | * all current requests to be flushed from the queue. | |
865 | */ | |
866 | #ifdef DEBUG | |
867 | printk("%s: DRIVE_CMD (null)\n", drive->name); | |
868 | #endif | |
869 | ide_end_drive_cmd(drive, | |
870 | hwif->INB(IDE_STATUS_REG), | |
871 | hwif->INB(IDE_ERROR_REG)); | |
872 | return ide_stopped; | |
873 | } | |
874 | ||
875 | /** | |
876 | * start_request - start of I/O and command issuing for IDE | |
877 | * | |
878 | * start_request() initiates handling of a new I/O request. It | |
879 | * accepts commands and I/O (read/write) requests. It also does | |
880 | * the final remapping for weird stuff like EZDrive. Once | |
881 | * device mapper can work sector level the EZDrive stuff can go away | |
882 | * | |
883 | * FIXME: this function needs a rename | |
884 | */ | |
885 | ||
886 | static ide_startstop_t start_request (ide_drive_t *drive, struct request *rq) | |
887 | { | |
888 | ide_startstop_t startstop; | |
889 | sector_t block; | |
890 | ||
891 | BUG_ON(!(rq->flags & REQ_STARTED)); | |
892 | ||
893 | #ifdef DEBUG | |
894 | printk("%s: start_request: current=0x%08lx\n", | |
895 | HWIF(drive)->name, (unsigned long) rq); | |
896 | #endif | |
897 | ||
898 | /* bail early if we've exceeded max_failures */ | |
899 | if (drive->max_failures && (drive->failures > drive->max_failures)) { | |
900 | goto kill_rq; | |
901 | } | |
902 | ||
903 | block = rq->sector; | |
904 | if (blk_fs_request(rq) && | |
905 | (drive->media == ide_disk || drive->media == ide_floppy)) { | |
906 | block += drive->sect0; | |
907 | } | |
908 | /* Yecch - this will shift the entire interval, | |
909 | possibly killing some innocent following sector */ | |
910 | if (block == 0 && drive->remap_0_to_1 == 1) | |
911 | block = 1; /* redirect MBR access to EZ-Drive partn table */ | |
912 | ||
913 | if (blk_pm_suspend_request(rq) && | |
914 | rq->pm->pm_step == ide_pm_state_start_suspend) | |
915 | /* Mark drive blocked when starting the suspend sequence. */ | |
916 | drive->blocked = 1; | |
917 | else if (blk_pm_resume_request(rq) && | |
918 | rq->pm->pm_step == ide_pm_state_start_resume) { | |
919 | /* | |
920 | * The first thing we do on wakeup is to wait for BSY bit to | |
921 | * go away (with a looong timeout) as a drive on this hwif may | |
922 | * just be POSTing itself. | |
923 | * We do that before even selecting as the "other" device on | |
924 | * the bus may be broken enough to walk on our toes at this | |
925 | * point. | |
926 | */ | |
927 | int rc; | |
928 | #ifdef DEBUG_PM | |
929 | printk("%s: Wakeup request inited, waiting for !BSY...\n", drive->name); | |
930 | #endif | |
931 | rc = ide_wait_not_busy(HWIF(drive), 35000); | |
932 | if (rc) | |
933 | printk(KERN_WARNING "%s: bus not ready on wakeup\n", drive->name); | |
934 | SELECT_DRIVE(drive); | |
935 | HWIF(drive)->OUTB(8, HWIF(drive)->io_ports[IDE_CONTROL_OFFSET]); | |
936 | rc = ide_wait_not_busy(HWIF(drive), 10000); | |
937 | if (rc) | |
938 | printk(KERN_WARNING "%s: drive not ready on wakeup\n", drive->name); | |
939 | } | |
940 | ||
941 | SELECT_DRIVE(drive); | |
942 | if (ide_wait_stat(&startstop, drive, drive->ready_stat, BUSY_STAT|DRQ_STAT, WAIT_READY)) { | |
943 | printk(KERN_ERR "%s: drive not ready for command\n", drive->name); | |
944 | return startstop; | |
945 | } | |
946 | if (!drive->special.all) { | |
947 | ide_driver_t *drv; | |
948 | ||
949 | if (rq->flags & (REQ_DRIVE_CMD | REQ_DRIVE_TASK)) | |
950 | return execute_drive_cmd(drive, rq); | |
951 | else if (rq->flags & REQ_DRIVE_TASKFILE) | |
952 | return execute_drive_cmd(drive, rq); | |
953 | else if (blk_pm_request(rq)) { | |
954 | #ifdef DEBUG_PM | |
955 | printk("%s: start_power_step(step: %d)\n", | |
956 | drive->name, rq->pm->pm_step); | |
957 | #endif | |
958 | startstop = ide_start_power_step(drive, rq); | |
959 | if (startstop == ide_stopped && | |
960 | rq->pm->pm_step == ide_pm_state_completed) | |
961 | ide_complete_pm_request(drive, rq); | |
962 | return startstop; | |
963 | } | |
964 | ||
965 | drv = *(ide_driver_t **)rq->rq_disk->private_data; | |
966 | return drv->do_request(drive, rq, block); | |
967 | } | |
968 | return do_special(drive); | |
969 | kill_rq: | |
970 | ide_kill_rq(drive, rq); | |
971 | return ide_stopped; | |
972 | } | |
973 | ||
974 | /** | |
975 | * ide_stall_queue - pause an IDE device | |
976 | * @drive: drive to stall | |
977 | * @timeout: time to stall for (jiffies) | |
978 | * | |
979 | * ide_stall_queue() can be used by a drive to give excess bandwidth back | |
980 | * to the hwgroup by sleeping for timeout jiffies. | |
981 | */ | |
982 | ||
983 | void ide_stall_queue (ide_drive_t *drive, unsigned long timeout) | |
984 | { | |
985 | if (timeout > WAIT_WORSTCASE) | |
986 | timeout = WAIT_WORSTCASE; | |
987 | drive->sleep = timeout + jiffies; | |
988 | drive->sleeping = 1; | |
989 | } | |
990 | ||
991 | EXPORT_SYMBOL(ide_stall_queue); | |
992 | ||
993 | #define WAKEUP(drive) ((drive)->service_start + 2 * (drive)->service_time) | |
994 | ||
995 | /** | |
996 | * choose_drive - select a drive to service | |
997 | * @hwgroup: hardware group to select on | |
998 | * | |
999 | * choose_drive() selects the next drive which will be serviced. | |
1000 | * This is necessary because the IDE layer can't issue commands | |
1001 | * to both drives on the same cable, unlike SCSI. | |
1002 | */ | |
1003 | ||
1004 | static inline ide_drive_t *choose_drive (ide_hwgroup_t *hwgroup) | |
1005 | { | |
1006 | ide_drive_t *drive, *best; | |
1007 | ||
1008 | repeat: | |
1009 | best = NULL; | |
1010 | drive = hwgroup->drive; | |
1011 | ||
1012 | /* | |
1013 | * drive is doing pre-flush, ordered write, post-flush sequence. even | |
1014 | * though that is 3 requests, it must be seen as a single transaction. | |
1015 | * we must not preempt this drive until that is complete | |
1016 | */ | |
1017 | if (blk_queue_flushing(drive->queue)) { | |
1018 | /* | |
1019 | * small race where queue could get replugged during | |
1020 | * the 3-request flush cycle, just yank the plug since | |
1021 | * we want it to finish asap | |
1022 | */ | |
1023 | blk_remove_plug(drive->queue); | |
1024 | return drive; | |
1025 | } | |
1026 | ||
1027 | do { | |
1028 | if ((!drive->sleeping || time_after_eq(jiffies, drive->sleep)) | |
1029 | && !elv_queue_empty(drive->queue)) { | |
1030 | if (!best | |
1031 | || (drive->sleeping && (!best->sleeping || time_before(drive->sleep, best->sleep))) | |
1032 | || (!best->sleeping && time_before(WAKEUP(drive), WAKEUP(best)))) | |
1033 | { | |
1034 | if (!blk_queue_plugged(drive->queue)) | |
1035 | best = drive; | |
1036 | } | |
1037 | } | |
1038 | } while ((drive = drive->next) != hwgroup->drive); | |
1039 | if (best && best->nice1 && !best->sleeping && best != hwgroup->drive && best->service_time > WAIT_MIN_SLEEP) { | |
1040 | long t = (signed long)(WAKEUP(best) - jiffies); | |
1041 | if (t >= WAIT_MIN_SLEEP) { | |
1042 | /* | |
1043 | * We *may* have some time to spare, but first let's see if | |
1044 | * someone can potentially benefit from our nice mood today.. | |
1045 | */ | |
1046 | drive = best->next; | |
1047 | do { | |
1048 | if (!drive->sleeping | |
1049 | && time_before(jiffies - best->service_time, WAKEUP(drive)) | |
1050 | && time_before(WAKEUP(drive), jiffies + t)) | |
1051 | { | |
1052 | ide_stall_queue(best, min_t(long, t, 10 * WAIT_MIN_SLEEP)); | |
1053 | goto repeat; | |
1054 | } | |
1055 | } while ((drive = drive->next) != best); | |
1056 | } | |
1057 | } | |
1058 | return best; | |
1059 | } | |
1060 | ||
1061 | /* | |
1062 | * Issue a new request to a drive from hwgroup | |
1063 | * Caller must have already done spin_lock_irqsave(&ide_lock, ..); | |
1064 | * | |
1065 | * A hwgroup is a serialized group of IDE interfaces. Usually there is | |
1066 | * exactly one hwif (interface) per hwgroup, but buggy controllers (eg. CMD640) | |
1067 | * may have both interfaces in a single hwgroup to "serialize" access. | |
1068 | * Or possibly multiple ISA interfaces can share a common IRQ by being grouped | |
1069 | * together into one hwgroup for serialized access. | |
1070 | * | |
1071 | * Note also that several hwgroups can end up sharing a single IRQ, | |
1072 | * possibly along with many other devices. This is especially common in | |
1073 | * PCI-based systems with off-board IDE controller cards. | |
1074 | * | |
1075 | * The IDE driver uses the single global ide_lock spinlock to protect | |
1076 | * access to the request queues, and to protect the hwgroup->busy flag. | |
1077 | * | |
1078 | * The first thread into the driver for a particular hwgroup sets the | |
1079 | * hwgroup->busy flag to indicate that this hwgroup is now active, | |
1080 | * and then initiates processing of the top request from the request queue. | |
1081 | * | |
1082 | * Other threads attempting entry notice the busy setting, and will simply | |
1083 | * queue their new requests and exit immediately. Note that hwgroup->busy | |
1084 | * remains set even when the driver is merely awaiting the next interrupt. | |
1085 | * Thus, the meaning is "this hwgroup is busy processing a request". | |
1086 | * | |
1087 | * When processing of a request completes, the completing thread or IRQ-handler | |
1088 | * will start the next request from the queue. If no more work remains, | |
1089 | * the driver will clear the hwgroup->busy flag and exit. | |
1090 | * | |
1091 | * The ide_lock (spinlock) is used to protect all access to the | |
1092 | * hwgroup->busy flag, but is otherwise not needed for most processing in | |
1093 | * the driver. This makes the driver much more friendlier to shared IRQs | |
1094 | * than previous designs, while remaining 100% (?) SMP safe and capable. | |
1095 | */ | |
1096 | static void ide_do_request (ide_hwgroup_t *hwgroup, int masked_irq) | |
1097 | { | |
1098 | ide_drive_t *drive; | |
1099 | ide_hwif_t *hwif; | |
1100 | struct request *rq; | |
1101 | ide_startstop_t startstop; | |
867f8b4e | 1102 | int loops = 0; |
1da177e4 LT |
1103 | |
1104 | /* for atari only: POSSIBLY BROKEN HERE(?) */ | |
1105 | ide_get_lock(ide_intr, hwgroup); | |
1106 | ||
1107 | /* caller must own ide_lock */ | |
1108 | BUG_ON(!irqs_disabled()); | |
1109 | ||
1110 | while (!hwgroup->busy) { | |
1111 | hwgroup->busy = 1; | |
1112 | drive = choose_drive(hwgroup); | |
1113 | if (drive == NULL) { | |
1114 | int sleeping = 0; | |
1115 | unsigned long sleep = 0; /* shut up, gcc */ | |
1116 | hwgroup->rq = NULL; | |
1117 | drive = hwgroup->drive; | |
1118 | do { | |
1119 | if (drive->sleeping && (!sleeping || time_before(drive->sleep, sleep))) { | |
1120 | sleeping = 1; | |
1121 | sleep = drive->sleep; | |
1122 | } | |
1123 | } while ((drive = drive->next) != hwgroup->drive); | |
1124 | if (sleeping) { | |
1125 | /* | |
1126 | * Take a short snooze, and then wake up this hwgroup again. | |
1127 | * This gives other hwgroups on the same a chance to | |
1128 | * play fairly with us, just in case there are big differences | |
1129 | * in relative throughputs.. don't want to hog the cpu too much. | |
1130 | */ | |
1131 | if (time_before(sleep, jiffies + WAIT_MIN_SLEEP)) | |
1132 | sleep = jiffies + WAIT_MIN_SLEEP; | |
1133 | #if 1 | |
1134 | if (timer_pending(&hwgroup->timer)) | |
1135 | printk(KERN_CRIT "ide_set_handler: timer already active\n"); | |
1136 | #endif | |
1137 | /* so that ide_timer_expiry knows what to do */ | |
1138 | hwgroup->sleeping = 1; | |
1139 | mod_timer(&hwgroup->timer, sleep); | |
1140 | /* we purposely leave hwgroup->busy==1 | |
1141 | * while sleeping */ | |
1142 | } else { | |
1143 | /* Ugly, but how can we sleep for the lock | |
1144 | * otherwise? perhaps from tq_disk? | |
1145 | */ | |
1146 | ||
1147 | /* for atari only */ | |
1148 | ide_release_lock(); | |
1149 | hwgroup->busy = 0; | |
1150 | } | |
1151 | ||
1152 | /* no more work for this hwgroup (for now) */ | |
1153 | return; | |
1154 | } | |
867f8b4e | 1155 | again: |
1da177e4 LT |
1156 | hwif = HWIF(drive); |
1157 | if (hwgroup->hwif->sharing_irq && | |
1158 | hwif != hwgroup->hwif && | |
1159 | hwif->io_ports[IDE_CONTROL_OFFSET]) { | |
1160 | /* set nIEN for previous hwif */ | |
1161 | SELECT_INTERRUPT(drive); | |
1162 | } | |
1163 | hwgroup->hwif = hwif; | |
1164 | hwgroup->drive = drive; | |
1165 | drive->sleeping = 0; | |
1166 | drive->service_start = jiffies; | |
1167 | ||
1168 | if (blk_queue_plugged(drive->queue)) { | |
1169 | printk(KERN_ERR "ide: huh? queue was plugged!\n"); | |
1170 | break; | |
1171 | } | |
1172 | ||
1173 | /* | |
1174 | * we know that the queue isn't empty, but this can happen | |
1175 | * if the q->prep_rq_fn() decides to kill a request | |
1176 | */ | |
1177 | rq = elv_next_request(drive->queue); | |
1178 | if (!rq) { | |
1179 | hwgroup->busy = 0; | |
1180 | break; | |
1181 | } | |
1182 | ||
1183 | /* | |
1184 | * Sanity: don't accept a request that isn't a PM request | |
1185 | * if we are currently power managed. This is very important as | |
1186 | * blk_stop_queue() doesn't prevent the elv_next_request() | |
1187 | * above to return us whatever is in the queue. Since we call | |
1188 | * ide_do_request() ourselves, we end up taking requests while | |
1189 | * the queue is blocked... | |
1190 | * | |
1191 | * We let requests forced at head of queue with ide-preempt | |
1192 | * though. I hope that doesn't happen too much, hopefully not | |
1193 | * unless the subdriver triggers such a thing in its own PM | |
1194 | * state machine. | |
867f8b4e BH |
1195 | * |
1196 | * We count how many times we loop here to make sure we service | |
1197 | * all drives in the hwgroup without looping for ever | |
1da177e4 LT |
1198 | */ |
1199 | if (drive->blocked && !blk_pm_request(rq) && !(rq->flags & REQ_PREEMPT)) { | |
867f8b4e BH |
1200 | drive = drive->next ? drive->next : hwgroup->drive; |
1201 | if (loops++ < 4 && !blk_queue_plugged(drive->queue)) | |
1202 | goto again; | |
1da177e4 LT |
1203 | /* We clear busy, there should be no pending ATA command at this point. */ |
1204 | hwgroup->busy = 0; | |
1205 | break; | |
1206 | } | |
1207 | ||
1208 | hwgroup->rq = rq; | |
1209 | ||
1210 | /* | |
1211 | * Some systems have trouble with IDE IRQs arriving while | |
1212 | * the driver is still setting things up. So, here we disable | |
1213 | * the IRQ used by this interface while the request is being started. | |
1214 | * This may look bad at first, but pretty much the same thing | |
1215 | * happens anyway when any interrupt comes in, IDE or otherwise | |
1216 | * -- the kernel masks the IRQ while it is being handled. | |
1217 | */ | |
1218 | if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq) | |
1219 | disable_irq_nosync(hwif->irq); | |
1220 | spin_unlock(&ide_lock); | |
1221 | local_irq_enable(); | |
1222 | /* allow other IRQs while we start this request */ | |
1223 | startstop = start_request(drive, rq); | |
1224 | spin_lock_irq(&ide_lock); | |
1225 | if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq) | |
1226 | enable_irq(hwif->irq); | |
1227 | if (startstop == ide_stopped) | |
1228 | hwgroup->busy = 0; | |
1229 | } | |
1230 | } | |
1231 | ||
1232 | /* | |
1233 | * Passes the stuff to ide_do_request | |
1234 | */ | |
1235 | void do_ide_request(request_queue_t *q) | |
1236 | { | |
1237 | ide_drive_t *drive = q->queuedata; | |
1238 | ||
1239 | ide_do_request(HWGROUP(drive), IDE_NO_IRQ); | |
1240 | } | |
1241 | ||
1242 | /* | |
1243 | * un-busy the hwgroup etc, and clear any pending DMA status. we want to | |
1244 | * retry the current request in pio mode instead of risking tossing it | |
1245 | * all away | |
1246 | */ | |
1247 | static ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error) | |
1248 | { | |
1249 | ide_hwif_t *hwif = HWIF(drive); | |
1250 | struct request *rq; | |
1251 | ide_startstop_t ret = ide_stopped; | |
1252 | ||
1253 | /* | |
1254 | * end current dma transaction | |
1255 | */ | |
1256 | ||
1257 | if (error < 0) { | |
1258 | printk(KERN_WARNING "%s: DMA timeout error\n", drive->name); | |
1259 | (void)HWIF(drive)->ide_dma_end(drive); | |
1260 | ret = ide_error(drive, "dma timeout error", | |
1261 | hwif->INB(IDE_STATUS_REG)); | |
1262 | } else { | |
1263 | printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name); | |
1264 | (void) hwif->ide_dma_timeout(drive); | |
1265 | } | |
1266 | ||
1267 | /* | |
1268 | * disable dma for now, but remember that we did so because of | |
1269 | * a timeout -- we'll reenable after we finish this next request | |
1270 | * (or rather the first chunk of it) in pio. | |
1271 | */ | |
1272 | drive->retry_pio++; | |
1273 | drive->state = DMA_PIO_RETRY; | |
1274 | (void) hwif->ide_dma_off_quietly(drive); | |
1275 | ||
1276 | /* | |
1277 | * un-busy drive etc (hwgroup->busy is cleared on return) and | |
1278 | * make sure request is sane | |
1279 | */ | |
1280 | rq = HWGROUP(drive)->rq; | |
1281 | HWGROUP(drive)->rq = NULL; | |
1282 | ||
1283 | rq->errors = 0; | |
1284 | ||
1285 | if (!rq->bio) | |
1286 | goto out; | |
1287 | ||
1288 | rq->sector = rq->bio->bi_sector; | |
1289 | rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9; | |
1290 | rq->hard_cur_sectors = rq->current_nr_sectors; | |
1291 | rq->buffer = bio_data(rq->bio); | |
1292 | out: | |
1293 | return ret; | |
1294 | } | |
1295 | ||
1296 | /** | |
1297 | * ide_timer_expiry - handle lack of an IDE interrupt | |
1298 | * @data: timer callback magic (hwgroup) | |
1299 | * | |
1300 | * An IDE command has timed out before the expected drive return | |
1301 | * occurred. At this point we attempt to clean up the current | |
1302 | * mess. If the current handler includes an expiry handler then | |
1303 | * we invoke the expiry handler, and providing it is happy the | |
1304 | * work is done. If that fails we apply generic recovery rules | |
1305 | * invoking the handler and checking the drive DMA status. We | |
1306 | * have an excessively incestuous relationship with the DMA | |
1307 | * logic that wants cleaning up. | |
1308 | */ | |
1309 | ||
1310 | void ide_timer_expiry (unsigned long data) | |
1311 | { | |
1312 | ide_hwgroup_t *hwgroup = (ide_hwgroup_t *) data; | |
1313 | ide_handler_t *handler; | |
1314 | ide_expiry_t *expiry; | |
1315 | unsigned long flags; | |
1316 | unsigned long wait = -1; | |
1317 | ||
1318 | spin_lock_irqsave(&ide_lock, flags); | |
1319 | ||
1320 | if ((handler = hwgroup->handler) == NULL) { | |
1321 | /* | |
1322 | * Either a marginal timeout occurred | |
1323 | * (got the interrupt just as timer expired), | |
1324 | * or we were "sleeping" to give other devices a chance. | |
1325 | * Either way, we don't really want to complain about anything. | |
1326 | */ | |
1327 | if (hwgroup->sleeping) { | |
1328 | hwgroup->sleeping = 0; | |
1329 | hwgroup->busy = 0; | |
1330 | } | |
1331 | } else { | |
1332 | ide_drive_t *drive = hwgroup->drive; | |
1333 | if (!drive) { | |
1334 | printk(KERN_ERR "ide_timer_expiry: hwgroup->drive was NULL\n"); | |
1335 | hwgroup->handler = NULL; | |
1336 | } else { | |
1337 | ide_hwif_t *hwif; | |
1338 | ide_startstop_t startstop = ide_stopped; | |
1339 | if (!hwgroup->busy) { | |
1340 | hwgroup->busy = 1; /* paranoia */ | |
1341 | printk(KERN_ERR "%s: ide_timer_expiry: hwgroup->busy was 0 ??\n", drive->name); | |
1342 | } | |
1343 | if ((expiry = hwgroup->expiry) != NULL) { | |
1344 | /* continue */ | |
1345 | if ((wait = expiry(drive)) > 0) { | |
1346 | /* reset timer */ | |
1347 | hwgroup->timer.expires = jiffies + wait; | |
1348 | add_timer(&hwgroup->timer); | |
1349 | spin_unlock_irqrestore(&ide_lock, flags); | |
1350 | return; | |
1351 | } | |
1352 | } | |
1353 | hwgroup->handler = NULL; | |
1354 | /* | |
1355 | * We need to simulate a real interrupt when invoking | |
1356 | * the handler() function, which means we need to | |
1357 | * globally mask the specific IRQ: | |
1358 | */ | |
1359 | spin_unlock(&ide_lock); | |
1360 | hwif = HWIF(drive); | |
1361 | #if DISABLE_IRQ_NOSYNC | |
1362 | disable_irq_nosync(hwif->irq); | |
1363 | #else | |
1364 | /* disable_irq_nosync ?? */ | |
1365 | disable_irq(hwif->irq); | |
1366 | #endif /* DISABLE_IRQ_NOSYNC */ | |
1367 | /* local CPU only, | |
1368 | * as if we were handling an interrupt */ | |
1369 | local_irq_disable(); | |
1370 | if (hwgroup->polling) { | |
1371 | startstop = handler(drive); | |
1372 | } else if (drive_is_ready(drive)) { | |
1373 | if (drive->waiting_for_dma) | |
1374 | (void) hwgroup->hwif->ide_dma_lostirq(drive); | |
1375 | (void)ide_ack_intr(hwif); | |
1376 | printk(KERN_WARNING "%s: lost interrupt\n", drive->name); | |
1377 | startstop = handler(drive); | |
1378 | } else { | |
1379 | if (drive->waiting_for_dma) { | |
1380 | startstop = ide_dma_timeout_retry(drive, wait); | |
1381 | } else | |
1382 | startstop = | |
1383 | ide_error(drive, "irq timeout", hwif->INB(IDE_STATUS_REG)); | |
1384 | } | |
1385 | drive->service_time = jiffies - drive->service_start; | |
1386 | spin_lock_irq(&ide_lock); | |
1387 | enable_irq(hwif->irq); | |
1388 | if (startstop == ide_stopped) | |
1389 | hwgroup->busy = 0; | |
1390 | } | |
1391 | } | |
1392 | ide_do_request(hwgroup, IDE_NO_IRQ); | |
1393 | spin_unlock_irqrestore(&ide_lock, flags); | |
1394 | } | |
1395 | ||
1396 | /** | |
1397 | * unexpected_intr - handle an unexpected IDE interrupt | |
1398 | * @irq: interrupt line | |
1399 | * @hwgroup: hwgroup being processed | |
1400 | * | |
1401 | * There's nothing really useful we can do with an unexpected interrupt, | |
1402 | * other than reading the status register (to clear it), and logging it. | |
1403 | * There should be no way that an irq can happen before we're ready for it, | |
1404 | * so we needn't worry much about losing an "important" interrupt here. | |
1405 | * | |
1406 | * On laptops (and "green" PCs), an unexpected interrupt occurs whenever | |
1407 | * the drive enters "idle", "standby", or "sleep" mode, so if the status | |
1408 | * looks "good", we just ignore the interrupt completely. | |
1409 | * | |
1410 | * This routine assumes __cli() is in effect when called. | |
1411 | * | |
1412 | * If an unexpected interrupt happens on irq15 while we are handling irq14 | |
1413 | * and if the two interfaces are "serialized" (CMD640), then it looks like | |
1414 | * we could screw up by interfering with a new request being set up for | |
1415 | * irq15. | |
1416 | * | |
1417 | * In reality, this is a non-issue. The new command is not sent unless | |
1418 | * the drive is ready to accept one, in which case we know the drive is | |
1419 | * not trying to interrupt us. And ide_set_handler() is always invoked | |
1420 | * before completing the issuance of any new drive command, so we will not | |
1421 | * be accidentally invoked as a result of any valid command completion | |
1422 | * interrupt. | |
1423 | * | |
1424 | * Note that we must walk the entire hwgroup here. We know which hwif | |
1425 | * is doing the current command, but we don't know which hwif burped | |
1426 | * mysteriously. | |
1427 | */ | |
1428 | ||
1429 | static void unexpected_intr (int irq, ide_hwgroup_t *hwgroup) | |
1430 | { | |
1431 | u8 stat; | |
1432 | ide_hwif_t *hwif = hwgroup->hwif; | |
1433 | ||
1434 | /* | |
1435 | * handle the unexpected interrupt | |
1436 | */ | |
1437 | do { | |
1438 | if (hwif->irq == irq) { | |
1439 | stat = hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]); | |
1440 | if (!OK_STAT(stat, READY_STAT, BAD_STAT)) { | |
1441 | /* Try to not flood the console with msgs */ | |
1442 | static unsigned long last_msgtime, count; | |
1443 | ++count; | |
1444 | if (time_after(jiffies, last_msgtime + HZ)) { | |
1445 | last_msgtime = jiffies; | |
1446 | printk(KERN_ERR "%s%s: unexpected interrupt, " | |
1447 | "status=0x%02x, count=%ld\n", | |
1448 | hwif->name, | |
1449 | (hwif->next==hwgroup->hwif) ? "" : "(?)", stat, count); | |
1450 | } | |
1451 | } | |
1452 | } | |
1453 | } while ((hwif = hwif->next) != hwgroup->hwif); | |
1454 | } | |
1455 | ||
1456 | /** | |
1457 | * ide_intr - default IDE interrupt handler | |
1458 | * @irq: interrupt number | |
1459 | * @dev_id: hwif group | |
1460 | * @regs: unused weirdness from the kernel irq layer | |
1461 | * | |
1462 | * This is the default IRQ handler for the IDE layer. You should | |
1463 | * not need to override it. If you do be aware it is subtle in | |
1464 | * places | |
1465 | * | |
1466 | * hwgroup->hwif is the interface in the group currently performing | |
1467 | * a command. hwgroup->drive is the drive and hwgroup->handler is | |
1468 | * the IRQ handler to call. As we issue a command the handlers | |
1469 | * step through multiple states, reassigning the handler to the | |
1470 | * next step in the process. Unlike a smart SCSI controller IDE | |
1471 | * expects the main processor to sequence the various transfer | |
1472 | * stages. We also manage a poll timer to catch up with most | |
1473 | * timeout situations. There are still a few where the handlers | |
1474 | * don't ever decide to give up. | |
1475 | * | |
1476 | * The handler eventually returns ide_stopped to indicate the | |
1477 | * request completed. At this point we issue the next request | |
1478 | * on the hwgroup and the process begins again. | |
1479 | */ | |
1480 | ||
1481 | irqreturn_t ide_intr (int irq, void *dev_id, struct pt_regs *regs) | |
1482 | { | |
1483 | unsigned long flags; | |
1484 | ide_hwgroup_t *hwgroup = (ide_hwgroup_t *)dev_id; | |
1485 | ide_hwif_t *hwif; | |
1486 | ide_drive_t *drive; | |
1487 | ide_handler_t *handler; | |
1488 | ide_startstop_t startstop; | |
1489 | ||
1490 | spin_lock_irqsave(&ide_lock, flags); | |
1491 | hwif = hwgroup->hwif; | |
1492 | ||
1493 | if (!ide_ack_intr(hwif)) { | |
1494 | spin_unlock_irqrestore(&ide_lock, flags); | |
1495 | return IRQ_NONE; | |
1496 | } | |
1497 | ||
1498 | if ((handler = hwgroup->handler) == NULL || hwgroup->polling) { | |
1499 | /* | |
1500 | * Not expecting an interrupt from this drive. | |
1501 | * That means this could be: | |
1502 | * (1) an interrupt from another PCI device | |
1503 | * sharing the same PCI INT# as us. | |
1504 | * or (2) a drive just entered sleep or standby mode, | |
1505 | * and is interrupting to let us know. | |
1506 | * or (3) a spurious interrupt of unknown origin. | |
1507 | * | |
1508 | * For PCI, we cannot tell the difference, | |
1509 | * so in that case we just ignore it and hope it goes away. | |
1510 | * | |
1511 | * FIXME: unexpected_intr should be hwif-> then we can | |
1512 | * remove all the ifdef PCI crap | |
1513 | */ | |
1514 | #ifdef CONFIG_BLK_DEV_IDEPCI | |
1515 | if (hwif->pci_dev && !hwif->pci_dev->vendor) | |
1516 | #endif /* CONFIG_BLK_DEV_IDEPCI */ | |
1517 | { | |
1518 | /* | |
1519 | * Probably not a shared PCI interrupt, | |
1520 | * so we can safely try to do something about it: | |
1521 | */ | |
1522 | unexpected_intr(irq, hwgroup); | |
1523 | #ifdef CONFIG_BLK_DEV_IDEPCI | |
1524 | } else { | |
1525 | /* | |
1526 | * Whack the status register, just in case | |
1527 | * we have a leftover pending IRQ. | |
1528 | */ | |
1529 | (void) hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]); | |
1530 | #endif /* CONFIG_BLK_DEV_IDEPCI */ | |
1531 | } | |
1532 | spin_unlock_irqrestore(&ide_lock, flags); | |
1533 | return IRQ_NONE; | |
1534 | } | |
1535 | drive = hwgroup->drive; | |
1536 | if (!drive) { | |
1537 | /* | |
1538 | * This should NEVER happen, and there isn't much | |
1539 | * we could do about it here. | |
1540 | * | |
1541 | * [Note - this can occur if the drive is hot unplugged] | |
1542 | */ | |
1543 | spin_unlock_irqrestore(&ide_lock, flags); | |
1544 | return IRQ_HANDLED; | |
1545 | } | |
1546 | if (!drive_is_ready(drive)) { | |
1547 | /* | |
1548 | * This happens regularly when we share a PCI IRQ with | |
1549 | * another device. Unfortunately, it can also happen | |
1550 | * with some buggy drives that trigger the IRQ before | |
1551 | * their status register is up to date. Hopefully we have | |
1552 | * enough advance overhead that the latter isn't a problem. | |
1553 | */ | |
1554 | spin_unlock_irqrestore(&ide_lock, flags); | |
1555 | return IRQ_NONE; | |
1556 | } | |
1557 | if (!hwgroup->busy) { | |
1558 | hwgroup->busy = 1; /* paranoia */ | |
1559 | printk(KERN_ERR "%s: ide_intr: hwgroup->busy was 0 ??\n", drive->name); | |
1560 | } | |
1561 | hwgroup->handler = NULL; | |
1562 | del_timer(&hwgroup->timer); | |
1563 | spin_unlock(&ide_lock); | |
1564 | ||
1565 | if (drive->unmask) | |
1566 | local_irq_enable(); | |
1567 | /* service this interrupt, may set handler for next interrupt */ | |
1568 | startstop = handler(drive); | |
1569 | spin_lock_irq(&ide_lock); | |
1570 | ||
1571 | /* | |
1572 | * Note that handler() may have set things up for another | |
1573 | * interrupt to occur soon, but it cannot happen until | |
1574 | * we exit from this routine, because it will be the | |
1575 | * same irq as is currently being serviced here, and Linux | |
1576 | * won't allow another of the same (on any CPU) until we return. | |
1577 | */ | |
1578 | drive->service_time = jiffies - drive->service_start; | |
1579 | if (startstop == ide_stopped) { | |
1580 | if (hwgroup->handler == NULL) { /* paranoia */ | |
1581 | hwgroup->busy = 0; | |
1582 | ide_do_request(hwgroup, hwif->irq); | |
1583 | } else { | |
1584 | printk(KERN_ERR "%s: ide_intr: huh? expected NULL handler " | |
1585 | "on exit\n", drive->name); | |
1586 | } | |
1587 | } | |
1588 | spin_unlock_irqrestore(&ide_lock, flags); | |
1589 | return IRQ_HANDLED; | |
1590 | } | |
1591 | ||
1592 | /** | |
1593 | * ide_init_drive_cmd - initialize a drive command request | |
1594 | * @rq: request object | |
1595 | * | |
1596 | * Initialize a request before we fill it in and send it down to | |
1597 | * ide_do_drive_cmd. Commands must be set up by this function. Right | |
1598 | * now it doesn't do a lot, but if that changes abusers will have a | |
1599 | * nasty suprise. | |
1600 | */ | |
1601 | ||
1602 | void ide_init_drive_cmd (struct request *rq) | |
1603 | { | |
1604 | memset(rq, 0, sizeof(*rq)); | |
1605 | rq->flags = REQ_DRIVE_CMD; | |
1606 | rq->ref_count = 1; | |
1607 | } | |
1608 | ||
1609 | EXPORT_SYMBOL(ide_init_drive_cmd); | |
1610 | ||
1611 | /** | |
1612 | * ide_do_drive_cmd - issue IDE special command | |
1613 | * @drive: device to issue command | |
1614 | * @rq: request to issue | |
1615 | * @action: action for processing | |
1616 | * | |
1617 | * This function issues a special IDE device request | |
1618 | * onto the request queue. | |
1619 | * | |
1620 | * If action is ide_wait, then the rq is queued at the end of the | |
1621 | * request queue, and the function sleeps until it has been processed. | |
1622 | * This is for use when invoked from an ioctl handler. | |
1623 | * | |
1624 | * If action is ide_preempt, then the rq is queued at the head of | |
1625 | * the request queue, displacing the currently-being-processed | |
1626 | * request and this function returns immediately without waiting | |
1627 | * for the new rq to be completed. This is VERY DANGEROUS, and is | |
1628 | * intended for careful use by the ATAPI tape/cdrom driver code. | |
1629 | * | |
1da177e4 LT |
1630 | * If action is ide_end, then the rq is queued at the end of the |
1631 | * request queue, and the function returns immediately without waiting | |
1632 | * for the new rq to be completed. This is again intended for careful | |
1633 | * use by the ATAPI tape/cdrom driver code. | |
1634 | */ | |
1635 | ||
1636 | int ide_do_drive_cmd (ide_drive_t *drive, struct request *rq, ide_action_t action) | |
1637 | { | |
1638 | unsigned long flags; | |
1639 | ide_hwgroup_t *hwgroup = HWGROUP(drive); | |
1640 | DECLARE_COMPLETION(wait); | |
1641 | int where = ELEVATOR_INSERT_BACK, err; | |
1642 | int must_wait = (action == ide_wait || action == ide_head_wait); | |
1643 | ||
1644 | rq->errors = 0; | |
1645 | rq->rq_status = RQ_ACTIVE; | |
1646 | ||
1647 | /* | |
1648 | * we need to hold an extra reference to request for safe inspection | |
1649 | * after completion | |
1650 | */ | |
1651 | if (must_wait) { | |
1652 | rq->ref_count++; | |
1653 | rq->waiting = &wait; | |
1654 | rq->end_io = blk_end_sync_rq; | |
1655 | } | |
1656 | ||
1657 | spin_lock_irqsave(&ide_lock, flags); | |
1658 | if (action == ide_preempt) | |
1659 | hwgroup->rq = NULL; | |
1660 | if (action == ide_preempt || action == ide_head_wait) { | |
1661 | where = ELEVATOR_INSERT_FRONT; | |
1662 | rq->flags |= REQ_PREEMPT; | |
1663 | } | |
1664 | __elv_add_request(drive->queue, rq, where, 0); | |
1665 | ide_do_request(hwgroup, IDE_NO_IRQ); | |
1666 | spin_unlock_irqrestore(&ide_lock, flags); | |
1667 | ||
1668 | err = 0; | |
1669 | if (must_wait) { | |
1670 | wait_for_completion(&wait); | |
1671 | rq->waiting = NULL; | |
1672 | if (rq->errors) | |
1673 | err = -EIO; | |
1674 | ||
1675 | blk_put_request(rq); | |
1676 | } | |
1677 | ||
1678 | return err; | |
1679 | } | |
1680 | ||
1681 | EXPORT_SYMBOL(ide_do_drive_cmd); |