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authorPierre Ossman <drzeus@drzeus.cx>2007-02-11 13:57:36 -0500
committerPierre Ossman <drzeus@drzeus.cx>2007-05-01 07:04:17 -0400
commit1c6a0718f0bfdab0d9b7da5f7b74f38a0058c03a (patch)
tree5e7f2a26d5d1782d87c596b40f874c6c0b8b8e1a /drivers/mmc/card/queue.c
parent98ac2162699f7e9880683cb954891817f20b607c (diff)
mmc: Move host and card drivers to subdirs
Clean up the drivers/mmc directory by moving card and host drivers into subdirectories. Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Diffstat (limited to 'drivers/mmc/card/queue.c')
-rw-r--r--drivers/mmc/card/queue.c249
1 files changed, 249 insertions, 0 deletions
diff --git a/drivers/mmc/card/queue.c b/drivers/mmc/card/queue.c
new file mode 100644
index 000000000000..aa75ac11a19e
--- /dev/null
+++ b/drivers/mmc/card/queue.c
@@ -0,0 +1,249 @@
1/*
2 * linux/drivers/mmc/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/module.h>
13#include <linux/blkdev.h>
14#include <linux/kthread.h>
15
16#include <linux/mmc/card.h>
17#include <linux/mmc/host.h>
18#include "queue.h"
19
20#define MMC_QUEUE_SUSPENDED (1 << 0)
21
22/*
23 * Prepare a MMC request. Essentially, this means passing the
24 * preparation off to the media driver. The media driver will
25 * create a mmc_io_request in req->special.
26 */
27static int mmc_prep_request(struct request_queue *q, struct request *req)
28{
29 struct mmc_queue *mq = q->queuedata;
30 int ret = BLKPREP_KILL;
31
32 if (blk_special_request(req)) {
33 /*
34 * Special commands already have the command
35 * blocks already setup in req->special.
36 */
37 BUG_ON(!req->special);
38
39 ret = BLKPREP_OK;
40 } else if (blk_fs_request(req) || blk_pc_request(req)) {
41 /*
42 * Block I/O requests need translating according
43 * to the protocol.
44 */
45 ret = mq->prep_fn(mq, req);
46 } else {
47 /*
48 * Everything else is invalid.
49 */
50 blk_dump_rq_flags(req, "MMC bad request");
51 }
52
53 if (ret == BLKPREP_OK)
54 req->cmd_flags |= REQ_DONTPREP;
55
56 return ret;
57}
58
59static int mmc_queue_thread(void *d)
60{
61 struct mmc_queue *mq = d;
62 struct request_queue *q = mq->queue;
63
64 /*
65 * Set iothread to ensure that we aren't put to sleep by
66 * the process freezing. We handle suspension ourselves.
67 */
68 current->flags |= PF_MEMALLOC|PF_NOFREEZE;
69
70 down(&mq->thread_sem);
71 do {
72 struct request *req = NULL;
73
74 spin_lock_irq(q->queue_lock);
75 set_current_state(TASK_INTERRUPTIBLE);
76 if (!blk_queue_plugged(q))
77 req = elv_next_request(q);
78 mq->req = req;
79 spin_unlock_irq(q->queue_lock);
80
81 if (!req) {
82 if (kthread_should_stop()) {
83 set_current_state(TASK_RUNNING);
84 break;
85 }
86 up(&mq->thread_sem);
87 schedule();
88 down(&mq->thread_sem);
89 continue;
90 }
91 set_current_state(TASK_RUNNING);
92
93 mq->issue_fn(mq, req);
94 } while (1);
95 up(&mq->thread_sem);
96
97 return 0;
98}
99
100/*
101 * Generic MMC request handler. This is called for any queue on a
102 * particular host. When the host is not busy, we look for a request
103 * on any queue on this host, and attempt to issue it. This may
104 * not be the queue we were asked to process.
105 */
106static void mmc_request(request_queue_t *q)
107{
108 struct mmc_queue *mq = q->queuedata;
109 struct request *req;
110 int ret;
111
112 if (!mq) {
113 printk(KERN_ERR "MMC: killing requests for dead queue\n");
114 while ((req = elv_next_request(q)) != NULL) {
115 do {
116 ret = end_that_request_chunk(req, 0,
117 req->current_nr_sectors << 9);
118 } while (ret);
119 }
120 return;
121 }
122
123 if (!mq->req)
124 wake_up_process(mq->thread);
125}
126
127/**
128 * mmc_init_queue - initialise a queue structure.
129 * @mq: mmc queue
130 * @card: mmc card to attach this queue
131 * @lock: queue lock
132 *
133 * Initialise a MMC card request queue.
134 */
135int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card, spinlock_t *lock)
136{
137 struct mmc_host *host = card->host;
138 u64 limit = BLK_BOUNCE_HIGH;
139 int ret;
140
141 if (mmc_dev(host)->dma_mask && *mmc_dev(host)->dma_mask)
142 limit = *mmc_dev(host)->dma_mask;
143
144 mq->card = card;
145 mq->queue = blk_init_queue(mmc_request, lock);
146 if (!mq->queue)
147 return -ENOMEM;
148
149 blk_queue_prep_rq(mq->queue, mmc_prep_request);
150 blk_queue_bounce_limit(mq->queue, limit);
151 blk_queue_max_sectors(mq->queue, host->max_req_size / 512);
152 blk_queue_max_phys_segments(mq->queue, host->max_phys_segs);
153 blk_queue_max_hw_segments(mq->queue, host->max_hw_segs);
154 blk_queue_max_segment_size(mq->queue, host->max_seg_size);
155
156 mq->queue->queuedata = mq;
157 mq->req = NULL;
158
159 mq->sg = kmalloc(sizeof(struct scatterlist) * host->max_phys_segs,
160 GFP_KERNEL);
161 if (!mq->sg) {
162 ret = -ENOMEM;
163 goto cleanup_queue;
164 }
165
166 init_MUTEX(&mq->thread_sem);
167
168 mq->thread = kthread_run(mmc_queue_thread, mq, "mmcqd");
169 if (IS_ERR(mq->thread)) {
170 ret = PTR_ERR(mq->thread);
171 goto free_sg;
172 }
173
174 return 0;
175
176 free_sg:
177 kfree(mq->sg);
178 mq->sg = NULL;
179 cleanup_queue:
180 blk_cleanup_queue(mq->queue);
181 return ret;
182}
183
184void mmc_cleanup_queue(struct mmc_queue *mq)
185{
186 request_queue_t *q = mq->queue;
187 unsigned long flags;
188
189 /* Mark that we should start throwing out stragglers */
190 spin_lock_irqsave(q->queue_lock, flags);
191 q->queuedata = NULL;
192 spin_unlock_irqrestore(q->queue_lock, flags);
193
194 /* Then terminate our worker thread */
195 kthread_stop(mq->thread);
196
197 kfree(mq->sg);
198 mq->sg = NULL;
199
200 blk_cleanup_queue(mq->queue);
201
202 mq->card = NULL;
203}
204EXPORT_SYMBOL(mmc_cleanup_queue);
205
206/**
207 * mmc_queue_suspend - suspend a MMC request queue
208 * @mq: MMC queue to suspend
209 *
210 * Stop the block request queue, and wait for our thread to
211 * complete any outstanding requests. This ensures that we
212 * won't suspend while a request is being processed.
213 */
214void mmc_queue_suspend(struct mmc_queue *mq)
215{
216 request_queue_t *q = mq->queue;
217 unsigned long flags;
218
219 if (!(mq->flags & MMC_QUEUE_SUSPENDED)) {
220 mq->flags |= MMC_QUEUE_SUSPENDED;
221
222 spin_lock_irqsave(q->queue_lock, flags);
223 blk_stop_queue(q);
224 spin_unlock_irqrestore(q->queue_lock, flags);
225
226 down(&mq->thread_sem);
227 }
228}
229
230/**
231 * mmc_queue_resume - resume a previously suspended MMC request queue
232 * @mq: MMC queue to resume
233 */
234void mmc_queue_resume(struct mmc_queue *mq)
235{
236 request_queue_t *q = mq->queue;
237 unsigned long flags;
238
239 if (mq->flags & MMC_QUEUE_SUSPENDED) {
240 mq->flags &= ~MMC_QUEUE_SUSPENDED;
241
242 up(&mq->thread_sem);
243
244 spin_lock_irqsave(q->queue_lock, flags);
245 blk_start_queue(q);
246 spin_unlock_irqrestore(q->queue_lock, flags);
247 }
248}
249