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| 1 | /* | |||
| 2 | * linux/drivers/mmc/mmc_queue.c | |||
| 3 | * | |||
| 4 | * Copyright (C) 2003 Russell King, All Rights Reserved. | |||
| 5 | * | |||
| 6 | * This program is free software; you can redistribute it and/or modify | |||
| 7 | * it under the terms of the GNU General Public License version 2 as | |||
| 8 | * published by the Free Software Foundation. | |||
| 9 | * | |||
| 10 | */ | |||
| 11 | #include <linux/module.h> | |||
| 12 | #include <linux/blkdev.h> | |||
| 13 | ||||
| 14 | #include <linux/mmc/card.h> | |||
| 15 | #include <linux/mmc/host.h> | |||
| 16 | #include "mmc_queue.h" | |||
| 17 | ||||
| 18 | #define MMC_QUEUE_EXIT (1 << 0) | |||
| 19 | #define MMC_QUEUE_SUSPENDED (1 << 1) | |||
| 20 | ||||
| 21 | /* | |||
| 22 | * Prepare a MMC request. Essentially, this means passing the | |||
| 23 | * preparation off to the media driver. The media driver will | |||
| 24 | * create a mmc_io_request in req->special. | |||
| 25 | */ | |||
| 0 | 0 | - | 26 | static int mmc_prep_request(struct request_queue *q, struct request *req) |
| 27 | { | |||
| 28 | struct mmc_queue *mq = q->queuedata; | |||
| 29 | int ret = BLKPREP_KILL; | |||
| 30 | ||||
| 0 | 0 | - | 31 | if (req->flags & REQ_SPECIAL) { |
| 32 | /* | |||
| 33 | * Special commands already have the command | |||
| 34 | * blocks already setup in req->special. | |||
| 35 | */ | |||
| 36 | BUG_ON(!req->special); | |||
| 0 | 0 | - | 36 | if (__builtin_expect ( ! ! ( ( ! req -> sp.. |
| 0 | 0 | - | 36 | do-while (0) |
| 37 | ||||
| 38 | ret = BLKPREP_OK; | |||
| 0 | 0 | - | 39 | } else if (req->flags & (REQ_CMD | REQ_BLOCK_PC)) { |
| 40 | /* | |||
| 41 | * Block I/O requests need translating according | |||
| 42 | * to the protocol. | |||
| 43 | */ | |||
| 44 | ret = mq->prep_fn(mq, req); | |||
| 45 | } else { | |||
| 46 | /* | |||
| 47 | * Everything else is invalid. | |||
| 48 | */ | |||
| 49 | blk_dump_rq_flags(req, "MMC bad request"); | |||
| 50 | } | |||
| 51 | ||||
| 0 | 0 | - | 52 | if (ret == BLKPREP_OK) |
| 53 | req->flags |= REQ_DONTPREP; | |||
| 54 | ||||
| 0 | - | 55 | return ret; | |
| 56 | } | |||
| 57 | ||||
| 0 | 0 | - | 58 | static int mmc_queue_thread(void *d) |
| 59 | { | |||
| 60 | struct mmc_queue *mq = d; | |||
| 61 | struct request_queue *q = mq->queue; | |||
| 62 | DECLARE_WAITQUEUE(wait, current); | |||
| 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 | daemonize("mmcqd"); | |||
| 71 | ||||
| 72 | complete(&mq->thread_complete); | |||
| 73 | ||||
| 74 | down(&mq->thread_sem); | |||
| 75 | add_wait_queue(&mq->thread_wq, &wait); | |||
| 76 | do { | |||
| 77 | struct request *req = NULL; | |||
| 78 | ||||
| 79 | spin_lock_irq(q->queue_lock); | |||
| 79 | do | |||
| 79 | do | |||
| 0 | 0 | - | 79 | do-while (0) |
| 0 | 0 | - | 79 | do-while (0) |
| 0 | 0 | - | 79 | do-while (0) |
| 80 | set_current_state(TASK_INTERRUPTIBLE); | |||
| 0 | 0 | - | 80 | do-while (0) |
| 0 | 0 | - | 81 | if (!blk_queue_plugged(q)) |
| 0 | 0 | - | 81 | ternary-?: __builtin_constant_p ( 7 ) |
| 82 | mq->req = req = elv_next_request(q); | |||
| 83 | spin_unlock_irq(q->queue_lock); | |||
| 83 | do | |||
| 83 | do | |||
| 0 | 0 | - | 83 | do-while (0) |
| 0 | 0 | - | 83 | do-while (0) |
| 0 | 0 | - | 83 | do-while (0) |
| 84 | ||||
| 0 | 0 | - | 85 | if (!req) { |
| 0 | 0 | - | 86 | if (mq->flags & MMC_QUEUE_EXIT) |
| 0 | - | 87 | break; | |
| 88 | up(&mq->thread_sem); | |||
| 89 | schedule(); | |||
| 90 | down(&mq->thread_sem); | |||
| 0 | - | 91 | continue; | |
| 92 | } | |||
| 93 | set_current_state(TASK_RUNNING); | |||
| 0 | 0 | - | 93 | do-while (0) |
| 94 | ||||
| 95 | mq->issue_fn(mq, req); | |||
| 0 | 0 | - | 96 | } while (1); |
| 97 | remove_wait_queue(&mq->thread_wq, &wait); | |||
| 98 | up(&mq->thread_sem); | |||
| 99 | ||||
| 100 | complete_and_exit(&mq->thread_complete, 0); | |||
| 0 | - | 101 | return 0; | |
| 102 | } | |||
| 103 | ||||
| 104 | /* | |||
| 105 | * Generic MMC request handler. This is called for any queue on a | |||
| 106 | * particular host. When the host is not busy, we look for a request | |||
| 107 | * on any queue on this host, and attempt to issue it. This may | |||
| 108 | * not be the queue we were asked to process. | |||
| 109 | */ | |||
| 0 | 0 | - | 110 | static void mmc_request(request_queue_t *q) |
| 111 | { | |||
| 112 | struct mmc_queue *mq = q->queuedata; | |||
| 113 | ||||
| 0 | 0 | - | 114 | if (!mq->req) |
| 115 | wake_up(&mq->thread_wq); | |||
| 116 | } | |||
| 117 | ||||
| 118 | /** | |||
| 119 | * mmc_init_queue - initialise a queue structure. | |||
| 120 | * @mq: mmc queue | |||
| 121 | * @card: mmc card to attach this queue | |||
| 122 | * @lock: queue lock | |||
| 123 | * | |||
| 124 | * Initialise a MMC card request queue. | |||
| 125 | */ | |||
| 0 | 0 | - | 126 | int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card, spinlock_t *lock) |
| 127 | { | |||
| 128 | struct mmc_host *host = card->host; | |||
| 129 | u64 limit = BLK_BOUNCE_HIGH; | |||
| 130 | int ret; | |||
| 131 | ||||
| 0 | 0 | - | 132 | if (host->dev->dma_mask && *host->dev->dma_mask) |
| 0 | - | 132 | T && T | |
| 0 | - | 132 | T && F | |
| 0 | - | 132 | F && _ | |
| 133 | limit = *host->dev->dma_mask; | |||
| 134 | ||||
| 135 | mq->card = card; | |||
| 136 | mq->queue = blk_init_queue(mmc_request, lock); | |||
| 0 | 0 | - | 137 | if (!mq->queue) |
| 0 | - | 138 | return -ENOMEM; | |
| 139 | ||||
| 140 | blk_queue_prep_rq(mq->queue, mmc_prep_request); | |||
| 141 | blk_queue_bounce_limit(mq->queue, limit); | |||
| 142 | blk_queue_max_sectors(mq->queue, host->max_sectors); | |||
| 143 | blk_queue_max_phys_segments(mq->queue, host->max_phys_segs); | |||
| 144 | blk_queue_max_hw_segments(mq->queue, host->max_hw_segs); | |||
| 145 | blk_queue_max_segment_size(mq->queue, host->max_seg_size); | |||
| 146 | ||||
| 147 | mq->queue->queuedata = mq; | |||
| 148 | mq->req = NULL; | |||
| 149 | ||||
| 150 | mq->sg = kmalloc(sizeof(struct scatterlist) * host->max_phys_segs, | |||
| 151 | GFP_KERNEL); | |||
| 0 | 0 | - | 152 | if (!mq->sg) { |
| 153 | ret = -ENOMEM; | |||
| 0 | - | 154 | goto cleanup; | |
| 155 | } | |||
| 156 | ||||
| 157 | init_completion(&mq->thread_complete); | |||
| 158 | init_waitqueue_head(&mq->thread_wq); | |||
| 159 | init_MUTEX(&mq->thread_sem); | |||
| 160 | ||||
| 161 | ret = kernel_thread(mmc_queue_thread, mq, CLONE_KERNEL); | |||
| 0 | 0 | - | 162 | if (ret >= 0) { |
| 163 | wait_for_completion(&mq->thread_complete); | |||
| 164 | init_completion(&mq->thread_complete); | |||
| 165 | ret = 0; | |||
| 0 | - | 166 | goto out; | |
| 167 | } | |||
| 168 | ||||
| 169 | cleanup: | |||
| 170 | kfree(mq->sg); | |||
| 171 | mq->sg = NULL; | |||
| 172 | ||||
| 173 | blk_cleanup_queue(mq->queue); | |||
| 174 | out: | |||
| 0 | - | 175 | return ret; | |
| 176 | } | |||
| 177 | EXPORT_SYMBOL(mmc_init_queue); | |||
| 178 | ||||
| 0 | 0 | - | 179 | void mmc_cleanup_queue(struct mmc_queue *mq) |
| 180 | { | |||
| 181 | mq->flags |= MMC_QUEUE_EXIT; | |||
| 182 | wake_up(&mq->thread_wq); | |||
| 183 | wait_for_completion(&mq->thread_complete); | |||
| 184 | ||||
| 185 | kfree(mq->sg); | |||
| 186 | mq->sg = NULL; | |||
| 187 | ||||
| 188 | blk_cleanup_queue(mq->queue); | |||
| 189 | ||||
| 190 | mq->card = NULL; | |||
| 191 | } | |||
| 192 | EXPORT_SYMBOL(mmc_cleanup_queue); | |||
| 193 | ||||
| 194 | /** | |||
| 195 | * mmc_queue_suspend - suspend a MMC request queue | |||
| 196 | * @mq: MMC queue to suspend | |||
| 197 | * | |||
| 198 | * Stop the block request queue, and wait for our thread to | |||
| 199 | * complete any outstanding requests. This ensures that we | |||
| 200 | * won't suspend while a request is being processed. | |||
| 201 | */ | |||
| 0 | 0 | - | 202 | void mmc_queue_suspend(struct mmc_queue *mq) |
| 203 | { | |||
| 204 | request_queue_t *q = mq->queue; | |||
| 205 | unsigned long flags; | |||
| 206 | ||||
| 0 | 0 | - | 207 | if (!(mq->flags & MMC_QUEUE_SUSPENDED)) { |
| 208 | mq->flags |= MMC_QUEUE_SUSPENDED; | |||
| 209 | ||||
| 210 | spin_lock_irqsave(q->queue_lock, flags); | |||
| 210 | do | |||
| 210 | do | |||
| 0 | 0 | - | 210 | do-while (0) |
| 0 | 0 | - | 210 | do-while (0) |
| 210 | do | |||
| 210 | do | |||
| 0 | 0 | - | 210 | do-while (0) |
| 0 | 0 | - | 210 | do-while (0) |
| 0 | 0 | - | 210 | do-while (0) |
| 211 | blk_stop_queue(q); | |||
| 212 | spin_unlock_irqrestore(q->queue_lock, flags); | |||
| 212 | do | |||
| 212 | do | |||
| 0 | 0 | - | 212 | do-while (0) |
| 0 | 0 | - | 212 | do-while (0) |
| 0 | 0 | - | 212 | do-while (0) |
| 213 | ||||
| 214 | down(&mq->thread_sem); | |||
| 215 | } | |||
| 216 | } | |||
| 217 | EXPORT_SYMBOL(mmc_queue_suspend); | |||
| 218 | ||||
| 219 | /** | |||
| 220 | * mmc_queue_resume - resume a previously suspended MMC request queue | |||
| 221 | * @mq: MMC queue to resume | |||
| 222 | */ | |||
| 0 | 0 | - | 223 | void mmc_queue_resume(struct mmc_queue *mq) |
| 224 | { | |||
| 225 | request_queue_t *q = mq->queue; | |||
| 226 | unsigned long flags; | |||
| 227 | ||||
| 0 | 0 | - | 228 | if (mq->flags & MMC_QUEUE_SUSPENDED) { |
| 229 | mq->flags &= ~MMC_QUEUE_SUSPENDED; | |||
| 230 | ||||
| 231 | up(&mq->thread_sem); | |||
| 232 | ||||
| 233 | spin_lock_irqsave(q->queue_lock, flags); | |||
| 233 | do | |||
| 233 | do | |||
| 0 | 0 | - | 233 | do-while (0) |
| 0 | 0 | - | 233 | do-while (0) |
| 233 | do | |||
| 233 | do | |||
| 0 | 0 | - | 233 | do-while (0) |
| 0 | 0 | - | 233 | do-while (0) |
| 0 | 0 | - | 233 | do-while (0) |
| 234 | blk_start_queue(q); | |||
| 235 | spin_unlock_irqrestore(q->queue_lock, flags); | |||
| 235 | do | |||
| 235 | do | |||
| 0 | 0 | - | 235 | do-while (0) |
| 0 | 0 | - | 235 | do-while (0) |
| 0 | 0 | - | 235 | do-while (0) |
| 236 | } | |||
| 237 | } | |||
| 238 | EXPORT_SYMBOL(mmc_queue_resume); | |||
| ***TER 0% (0/100) of SOURCE FILE mmc_queue.c | ||||