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Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[linux-2.6.git] / drivers / mmc / card / queue.c
blobfa9632eb63f14cc9af971f290989f13263c3cbfd
1 /*
2 * linux/drivers/mmc/card/queue.c
3 *
4 * Copyright (C) 2003 Russell King, All Rights Reserved.
5 * Copyright 2006-2007 Pierre Ossman
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 *
11 */
12 #include <linux/slab.h>
13 #include <linux/module.h>
14 #include <linux/blkdev.h>
15 #include <linux/freezer.h>
16 #include <linux/kthread.h>
17 #include <linux/scatterlist.h>
18
19 #include <linux/mmc/card.h>
20 #include <linux/mmc/host.h>
21 #include "queue.h"
22
23 #define MMC_QUEUE_BOUNCESZ 65536
24
25 /*
26 * Prepare a MMC request. This just filters out odd stuff.
27 */
28 static int mmc_prep_request(struct request_queue *q, struct request *req)
29 {
30 struct mmc_queue *mq = q->queuedata;
31
32 /*
33 * We only like normal block requests and discards.
34 */
35 if (req->cmd_type != REQ_TYPE_FS && !(req->cmd_flags & REQ_DISCARD)) {
36 blk_dump_rq_flags(req, "MMC bad request");
37 return BLKPREP_KILL;
38 }
39
40 if (mq && mmc_card_removed(mq->card))
41 return BLKPREP_KILL;
42
43 req->cmd_flags |= REQ_DONTPREP;
44
45 return BLKPREP_OK;
46 }
47
48 static int mmc_queue_thread(void *d)
49 {
50 struct mmc_queue *mq = d;
51 struct request_queue *q = mq->queue;
52
53 current->flags |= PF_MEMALLOC;
54
55 down(&mq->thread_sem);
56 do {
57 struct request *req = NULL;
58 struct mmc_queue_req *tmp;
59 unsigned int cmd_flags = 0;
60
61 spin_lock_irq(q->queue_lock);
62 set_current_state(TASK_INTERRUPTIBLE);
63 req = blk_fetch_request(q);
64 mq->mqrq_cur->req = req;
65 spin_unlock_irq(q->queue_lock);
66
67 if (req || mq->mqrq_prev->req) {
68 set_current_state(TASK_RUNNING);
69 cmd_flags = req ? req->cmd_flags : 0;
70 mq->issue_fn(mq, req);
71 if (mq->flags & MMC_QUEUE_NEW_REQUEST) {
72 mq->flags &= ~MMC_QUEUE_NEW_REQUEST;
73 continue; /* fetch again */
74 }
75
76 /*
77 * Current request becomes previous request
78 * and vice versa.
79 * In case of special requests, current request
80 * has been finished. Do not assign it to previous
81 * request.
82 */
83 if (cmd_flags & MMC_REQ_SPECIAL_MASK)
84 mq->mqrq_cur->req = NULL;
85
86 mq->mqrq_prev->brq.mrq.data = NULL;
87 mq->mqrq_prev->req = NULL;
88 tmp = mq->mqrq_prev;
89 mq->mqrq_prev = mq->mqrq_cur;
90 mq->mqrq_cur = tmp;
91 } else {
92 if (kthread_should_stop()) {
93 set_current_state(TASK_RUNNING);
94 break;
95 }
96 up(&mq->thread_sem);
97 schedule();
98 down(&mq->thread_sem);
99 }
100 } while (1);
101 up(&mq->thread_sem);
102
103 return 0;
104 }
105
106 /*
107 * Generic MMC request handler. This is called for any queue on a
108 * particular host. When the host is not busy, we look for a request
109 * on any queue on this host, and attempt to issue it. This may
110 * not be the queue we were asked to process.
111 */
112 static void mmc_request_fn(struct request_queue *q)
113 {
114 struct mmc_queue *mq = q->queuedata;
115 struct request *req;
116 unsigned long flags;
117 struct mmc_context_info *cntx;
118
119 if (!mq) {
120 while ((req = blk_fetch_request(q)) != NULL) {
121 req->cmd_flags |= REQ_QUIET;
122 __blk_end_request_all(req, -EIO);
123 }
124 return;
125 }
126
127 cntx = &mq->card->host->context_info;
128 if (!mq->mqrq_cur->req && mq->mqrq_prev->req) {
129 /*
130 * New MMC request arrived when MMC thread may be
131 * blocked on the previous request to be complete
132 * with no current request fetched
133 */
134 spin_lock_irqsave(&cntx->lock, flags);
135 if (cntx->is_waiting_last_req) {
136 cntx->is_new_req = true;
137 wake_up_interruptible(&cntx->wait);
138 }
139 spin_unlock_irqrestore(&cntx->lock, flags);
140 } else if (!mq->mqrq_cur->req && !mq->mqrq_prev->req)
141 wake_up_process(mq->thread);
142 }
143
144 static struct scatterlist *mmc_alloc_sg(int sg_len, int *err)
145 {
146 struct scatterlist *sg;
147
148 sg = kmalloc(sizeof(struct scatterlist)*sg_len, GFP_KERNEL);
149 if (!sg)
150 *err = -ENOMEM;
151 else {
152 *err = 0;
153 sg_init_table(sg, sg_len);
154 }
155
156 return sg;
157 }
158
159 static void mmc_queue_setup_discard(struct request_queue *q,
160 struct mmc_card *card)
161 {
162 unsigned max_discard;
163
164 max_discard = mmc_calc_max_discard(card);
165 if (!max_discard)
166 return;
167
168 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
169 q->limits.max_discard_sectors = max_discard;
170 if (card->erased_byte == 0 && !mmc_can_discard(card))
171 q->limits.discard_zeroes_data = 1;
172 q->limits.discard_granularity = card->pref_erase << 9;
173 /* granularity must not be greater than max. discard */
174 if (card->pref_erase > max_discard)
175 q->limits.discard_granularity = 0;
176 if (mmc_can_secure_erase_trim(card))
177 queue_flag_set_unlocked(QUEUE_FLAG_SECDISCARD, q);
178 }
179
180 /**
181 * mmc_init_queue - initialise a queue structure.
182 * @mq: mmc queue
183 * @card: mmc card to attach this queue
184 * @lock: queue lock
185 * @subname: partition subname
186 *
187 * Initialise a MMC card request queue.
188 */
189 int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card,
190 spinlock_t *lock, const char *subname)
191 {
192 struct mmc_host *host = card->host;
193 u64 limit = BLK_BOUNCE_HIGH;
194 int ret;
195 struct mmc_queue_req *mqrq_cur = &mq->mqrq[0];
196 struct mmc_queue_req *mqrq_prev = &mq->mqrq[1];
197
198 if (mmc_dev(host)->dma_mask && *mmc_dev(host)->dma_mask)
199 limit = *mmc_dev(host)->dma_mask;
200
201 mq->card = card;
202 mq->queue = blk_init_queue(mmc_request_fn, lock);
203 if (!mq->queue)
204 return -ENOMEM;
205
206 mq->mqrq_cur = mqrq_cur;
207 mq->mqrq_prev = mqrq_prev;
208 mq->queue->queuedata = mq;
209
210 blk_queue_prep_rq(mq->queue, mmc_prep_request);
211 queue_flag_set_unlocked(QUEUE_FLAG_NONROT, mq->queue);
212 if (mmc_can_erase(card))
213 mmc_queue_setup_discard(mq->queue, card);
214
215 #ifdef CONFIG_MMC_BLOCK_BOUNCE
216 if (host->max_segs == 1) {
217 unsigned int bouncesz;
218
219 bouncesz = MMC_QUEUE_BOUNCESZ;
220
221 if (bouncesz > host->max_req_size)
222 bouncesz = host->max_req_size;
223 if (bouncesz > host->max_seg_size)
224 bouncesz = host->max_seg_size;
225 if (bouncesz > (host->max_blk_count * 512))
226 bouncesz = host->max_blk_count * 512;
227
228 if (bouncesz > 512) {
229 mqrq_cur->bounce_buf = kmalloc(bouncesz, GFP_KERNEL);
230 if (!mqrq_cur->bounce_buf) {
231 pr_warning("%s: unable to "
232 "allocate bounce cur buffer\n",
233 mmc_card_name(card));
234 }
235 mqrq_prev->bounce_buf = kmalloc(bouncesz, GFP_KERNEL);
236 if (!mqrq_prev->bounce_buf) {
237 pr_warning("%s: unable to "
238 "allocate bounce prev buffer\n",
239 mmc_card_name(card));
240 kfree(mqrq_cur->bounce_buf);
241 mqrq_cur->bounce_buf = NULL;
242 }
243 }
244
245 if (mqrq_cur->bounce_buf && mqrq_prev->bounce_buf) {
246 blk_queue_bounce_limit(mq->queue, BLK_BOUNCE_ANY);
247 blk_queue_max_hw_sectors(mq->queue, bouncesz / 512);
248 blk_queue_max_segments(mq->queue, bouncesz / 512);
249 blk_queue_max_segment_size(mq->queue, bouncesz);
250
251 mqrq_cur->sg = mmc_alloc_sg(1, &ret);
252 if (ret)
253 goto cleanup_queue;
254
255 mqrq_cur->bounce_sg =
256 mmc_alloc_sg(bouncesz / 512, &ret);
257 if (ret)
258 goto cleanup_queue;
259
260 mqrq_prev->sg = mmc_alloc_sg(1, &ret);
261 if (ret)
262 goto cleanup_queue;
263
264 mqrq_prev->bounce_sg =
265 mmc_alloc_sg(bouncesz / 512, &ret);
266 if (ret)
267 goto cleanup_queue;
268 }
269 }
270 #endif
271
272 if (!mqrq_cur->bounce_buf && !mqrq_prev->bounce_buf) {
273 blk_queue_bounce_limit(mq->queue, limit);
274 blk_queue_max_hw_sectors(mq->queue,
275 min(host->max_blk_count, host->max_req_size / 512));
276 blk_queue_max_segments(mq->queue, host->max_segs);
277 blk_queue_max_segment_size(mq->queue, host->max_seg_size);
278
279 mqrq_cur->sg = mmc_alloc_sg(host->max_segs, &ret);
280 if (ret)
281 goto cleanup_queue;
282
283
284 mqrq_prev->sg = mmc_alloc_sg(host->max_segs, &ret);
285 if (ret)
286 goto cleanup_queue;
287 }
288
289 sema_init(&mq->thread_sem, 1);
290
291 mq->thread = kthread_run(mmc_queue_thread, mq, "mmcqd/%d%s",
292 host->index, subname ? subname : "");
293
294 if (IS_ERR(mq->thread)) {
295 ret = PTR_ERR(mq->thread);
296 goto free_bounce_sg;
297 }
298
299 return 0;
300 free_bounce_sg:
301 kfree(mqrq_cur->bounce_sg);
302 mqrq_cur->bounce_sg = NULL;
303 kfree(mqrq_prev->bounce_sg);
304 mqrq_prev->bounce_sg = NULL;
305
306 cleanup_queue:
307 kfree(mqrq_cur->sg);
308 mqrq_cur->sg = NULL;
309 kfree(mqrq_cur->bounce_buf);
310 mqrq_cur->bounce_buf = NULL;
311
312 kfree(mqrq_prev->sg);
313 mqrq_prev->sg = NULL;
314 kfree(mqrq_prev->bounce_buf);
315 mqrq_prev->bounce_buf = NULL;
316
317 blk_cleanup_queue(mq->queue);
318 return ret;
319 }
320
321 void mmc_cleanup_queue(struct mmc_queue *mq)
322 {
323 struct request_queue *q = mq->queue;
324 unsigned long flags;
325 struct mmc_queue_req *mqrq_cur = mq->mqrq_cur;
326 struct mmc_queue_req *mqrq_prev = mq->mqrq_prev;
327
328 /* Make sure the queue isn't suspended, as that will deadlock */
329 mmc_queue_resume(mq);
330
331 /* Then terminate our worker thread */
332 kthread_stop(mq->thread);
333
334 /* Empty the queue */
335 spin_lock_irqsave(q->queue_lock, flags);
336 q->queuedata = NULL;
337 blk_start_queue(q);
338 spin_unlock_irqrestore(q->queue_lock, flags);
339
340 kfree(mqrq_cur->bounce_sg);
341 mqrq_cur->bounce_sg = NULL;
342
343 kfree(mqrq_cur->sg);
344 mqrq_cur->sg = NULL;
345
346 kfree(mqrq_cur->bounce_buf);
347 mqrq_cur->bounce_buf = NULL;
348
349 kfree(mqrq_prev->bounce_sg);
350 mqrq_prev->bounce_sg = NULL;
351
352 kfree(mqrq_prev->sg);
353 mqrq_prev->sg = NULL;
354
355 kfree(mqrq_prev->bounce_buf);
356 mqrq_prev->bounce_buf = NULL;
357
358 mq->card = NULL;
359 }
360 EXPORT_SYMBOL(mmc_cleanup_queue);
361
362 int mmc_packed_init(struct mmc_queue *mq, struct mmc_card *card)
363 {
364 struct mmc_queue_req *mqrq_cur = &mq->mqrq[0];
365 struct mmc_queue_req *mqrq_prev = &mq->mqrq[1];
366 int ret = 0;
367
368
369 mqrq_cur->packed = kzalloc(sizeof(struct mmc_packed), GFP_KERNEL);
370 if (!mqrq_cur->packed) {
371 pr_warn("%s: unable to allocate packed cmd for mqrq_cur\n",
372 mmc_card_name(card));
373 ret = -ENOMEM;
374 goto out;
375 }
376
377 mqrq_prev->packed = kzalloc(sizeof(struct mmc_packed), GFP_KERNEL);
378 if (!mqrq_prev->packed) {
379 pr_warn("%s: unable to allocate packed cmd for mqrq_prev\n",
380 mmc_card_name(card));
381 kfree(mqrq_cur->packed);
382 mqrq_cur->packed = NULL;
383 ret = -ENOMEM;
384 goto out;
385 }
386
387 INIT_LIST_HEAD(&mqrq_cur->packed->list);
388 INIT_LIST_HEAD(&mqrq_prev->packed->list);
389
390 out:
391 return ret;
392 }
393
394 void mmc_packed_clean(struct mmc_queue *mq)
395 {
396 struct mmc_queue_req *mqrq_cur = &mq->mqrq[0];
397 struct mmc_queue_req *mqrq_prev = &mq->mqrq[1];
398
399 kfree(mqrq_cur->packed);
400 mqrq_cur->packed = NULL;
401 kfree(mqrq_prev->packed);
402 mqrq_prev->packed = NULL;
403 }
404
405 /**
406 * mmc_queue_suspend - suspend a MMC request queue
407 * @mq: MMC queue to suspend
408 *
409 * Stop the block request queue, and wait for our thread to
410 * complete any outstanding requests. This ensures that we
411 * won't suspend while a request is being processed.
412 */
413 void mmc_queue_suspend(struct mmc_queue *mq)
414 {
415 struct request_queue *q = mq->queue;
416 unsigned long flags;
417
418 if (!(mq->flags & MMC_QUEUE_SUSPENDED)) {
419 mq->flags |= MMC_QUEUE_SUSPENDED;
420
421 spin_lock_irqsave(q->queue_lock, flags);
422 blk_stop_queue(q);
423 spin_unlock_irqrestore(q->queue_lock, flags);
424
425 down(&mq->thread_sem);
426 }
427 }
428
429 /**
430 * mmc_queue_resume - resume a previously suspended MMC request queue
431 * @mq: MMC queue to resume
432 */
433 void mmc_queue_resume(struct mmc_queue *mq)
434 {
435 struct request_queue *q = mq->queue;
436 unsigned long flags;
437
438 if (mq->flags & MMC_QUEUE_SUSPENDED) {
439 mq->flags &= ~MMC_QUEUE_SUSPENDED;
440
441 up(&mq->thread_sem);
442
443 spin_lock_irqsave(q->queue_lock, flags);
444 blk_start_queue(q);
445 spin_unlock_irqrestore(q->queue_lock, flags);
446 }
447 }
448
449 static unsigned int mmc_queue_packed_map_sg(struct mmc_queue *mq,
450 struct mmc_packed *packed,
451 struct scatterlist *sg,
452 enum mmc_packed_type cmd_type)
453 {
454 struct scatterlist *__sg = sg;
455 unsigned int sg_len = 0;
456 struct request *req;
457
458 if (mmc_packed_wr(cmd_type)) {
459 unsigned int hdr_sz = mmc_large_sector(mq->card) ? 4096 : 512;
460 unsigned int max_seg_sz = queue_max_segment_size(mq->queue);
461 unsigned int len, remain, offset = 0;
462 u8 *buf = (u8 *)packed->cmd_hdr;
463
464 remain = hdr_sz;
465 do {
466 len = min(remain, max_seg_sz);
467 sg_set_buf(__sg, buf + offset, len);
468 offset += len;
469 remain -= len;
470 (__sg++)->page_link &= ~0x02;
471 sg_len++;
472 } while (remain);
473 }
474
475 list_for_each_entry(req, &packed->list, queuelist) {
476 sg_len += blk_rq_map_sg(mq->queue, req, __sg);
477 __sg = sg + (sg_len - 1);
478 (__sg++)->page_link &= ~0x02;
479 }
480 sg_mark_end(sg + (sg_len - 1));
481 return sg_len;
482 }
483
484 /*
485 * Prepare the sg list(s) to be handed of to the host driver
486 */
487 unsigned int mmc_queue_map_sg(struct mmc_queue *mq, struct mmc_queue_req *mqrq)
488 {
489 unsigned int sg_len;
490 size_t buflen;
491 struct scatterlist *sg;
492 enum mmc_packed_type cmd_type;
493 int i;
494
495 cmd_type = mqrq->cmd_type;
496
497 if (!mqrq->bounce_buf) {
498 if (mmc_packed_cmd(cmd_type))
499 return mmc_queue_packed_map_sg(mq, mqrq->packed,
500 mqrq->sg, cmd_type);
501 else
502 return blk_rq_map_sg(mq->queue, mqrq->req, mqrq->sg);
503 }
504
505 BUG_ON(!mqrq->bounce_sg);
506
507 if (mmc_packed_cmd(cmd_type))
508 sg_len = mmc_queue_packed_map_sg(mq, mqrq->packed,
509 mqrq->bounce_sg, cmd_type);
510 else
511 sg_len = blk_rq_map_sg(mq->queue, mqrq->req, mqrq->bounce_sg);
512
513 mqrq->bounce_sg_len = sg_len;
514
515 buflen = 0;
516 for_each_sg(mqrq->bounce_sg, sg, sg_len, i)
517 buflen += sg->length;
518
519 sg_init_one(mqrq->sg, mqrq->bounce_buf, buflen);
520
521 return 1;
522 }
523
524 /*
525 * If writing, bounce the data to the buffer before the request
526 * is sent to the host driver
527 */
528 void mmc_queue_bounce_pre(struct mmc_queue_req *mqrq)
529 {
530 if (!mqrq->bounce_buf)
531 return;
532
533 if (rq_data_dir(mqrq->req) != WRITE)
534 return;
535
536 sg_copy_to_buffer(mqrq->bounce_sg, mqrq->bounce_sg_len,
537 mqrq->bounce_buf, mqrq->sg[0].length);
538 }
539
540 /*
541 * If reading, bounce the data from the buffer after the request
542 * has been handled by the host driver
543 */
544 void mmc_queue_bounce_post(struct mmc_queue_req *mqrq)
545 {
546 if (!mqrq->bounce_buf)
547 return;
548
549 if (rq_data_dir(mqrq->req) != READ)
550 return;
551
552 sg_copy_from_buffer(mqrq->bounce_sg, mqrq->bounce_sg_len,
553 mqrq->bounce_buf, mqrq->sg[0].length);
554 }
Linus' kernel tree