diff options
Diffstat (limited to 'drivers/mmc/card/queue.c')
| -rw-r--r-- | drivers/mmc/card/queue.c | 556 |
1 files changed, 556 insertions, 0 deletions
diff --git a/drivers/mmc/card/queue.c b/drivers/mmc/card/queue.c new file mode 100644 index 000000000..8efa3684a --- /dev/null +++ b/drivers/mmc/card/queue.c @@ -0,0 +1,556 @@ +/* + * linux/drivers/mmc/card/queue.c + * + * Copyright (C) 2003 Russell King, All Rights Reserved. + * Copyright 2006-2007 Pierre Ossman + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/blkdev.h> +#include <linux/freezer.h> +#include <linux/kthread.h> +#include <linux/scatterlist.h> +#include <linux/dma-mapping.h> + +#include <linux/mmc/card.h> +#include <linux/mmc/host.h> +#include "queue.h" + +#define MMC_QUEUE_BOUNCESZ 65536 + +/* + * Prepare a MMC request. This just filters out odd stuff. + */ +static int mmc_prep_request(struct request_queue *q, struct request *req) +{ + struct mmc_queue *mq = q->queuedata; + + /* + * We only like normal block requests and discards. + */ + if (req->cmd_type != REQ_TYPE_FS && !(req->cmd_flags & REQ_DISCARD)) { + blk_dump_rq_flags(req, "MMC bad request"); + return BLKPREP_KILL; + } + + if (mq && (mmc_card_removed(mq->card) || mmc_access_rpmb(mq))) + return BLKPREP_KILL; + + req->cmd_flags |= REQ_DONTPREP; + + return BLKPREP_OK; +} + +static int mmc_queue_thread(void *d) +{ + struct mmc_queue *mq = d; + struct request_queue *q = mq->queue; + + current->flags |= PF_MEMALLOC; + + down(&mq->thread_sem); + do { + struct request *req = NULL; + struct mmc_queue_req *tmp; + unsigned int cmd_flags = 0; + + spin_lock_irq(q->queue_lock); + set_current_state(TASK_INTERRUPTIBLE); + req = blk_fetch_request(q); + mq->mqrq_cur->req = req; + spin_unlock_irq(q->queue_lock); + + if (req || mq->mqrq_prev->req) { + set_current_state(TASK_RUNNING); + cmd_flags = req ? req->cmd_flags : 0; + mq->issue_fn(mq, req); + if (mq->flags & MMC_QUEUE_NEW_REQUEST) { + mq->flags &= ~MMC_QUEUE_NEW_REQUEST; + continue; /* fetch again */ + } + + /* + * Current request becomes previous request + * and vice versa. + * In case of special requests, current request + * has been finished. Do not assign it to previous + * request. + */ + if (cmd_flags & MMC_REQ_SPECIAL_MASK) + mq->mqrq_cur->req = NULL; + + mq->mqrq_prev->brq.mrq.data = NULL; + mq->mqrq_prev->req = NULL; + tmp = mq->mqrq_prev; + mq->mqrq_prev = mq->mqrq_cur; + mq->mqrq_cur = tmp; + } else { + if (kthread_should_stop()) { + set_current_state(TASK_RUNNING); + break; + } + up(&mq->thread_sem); + schedule(); + down(&mq->thread_sem); + } + } while (1); + up(&mq->thread_sem); + + return 0; +} + +/* + * Generic MMC request handler. This is called for any queue on a + * particular host. When the host is not busy, we look for a request + * on any queue on this host, and attempt to issue it. This may + * not be the queue we were asked to process. + */ +static void mmc_request_fn(struct request_queue *q) +{ + struct mmc_queue *mq = q->queuedata; + struct request *req; + unsigned long flags; + struct mmc_context_info *cntx; + + if (!mq) { + while ((req = blk_fetch_request(q)) != NULL) { + req->cmd_flags |= REQ_QUIET; + __blk_end_request_all(req, -EIO); + } + return; + } + + cntx = &mq->card->host->context_info; + if (!mq->mqrq_cur->req && mq->mqrq_prev->req) { + /* + * New MMC request arrived when MMC thread may be + * blocked on the previous request to be complete + * with no current request fetched + */ + spin_lock_irqsave(&cntx->lock, flags); + if (cntx->is_waiting_last_req) { + cntx->is_new_req = true; + wake_up_interruptible(&cntx->wait); + } + spin_unlock_irqrestore(&cntx->lock, flags); + } else if (!mq->mqrq_cur->req && !mq->mqrq_prev->req) + wake_up_process(mq->thread); +} + +static struct scatterlist *mmc_alloc_sg(int sg_len, int *err) +{ + struct scatterlist *sg; + + sg = kmalloc(sizeof(struct scatterlist)*sg_len, GFP_KERNEL); + if (!sg) + *err = -ENOMEM; + else { + *err = 0; + sg_init_table(sg, sg_len); + } + + return sg; +} + +static void mmc_queue_setup_discard(struct request_queue *q, + struct mmc_card *card) +{ + unsigned max_discard; + + max_discard = mmc_calc_max_discard(card); + if (!max_discard) + return; + + queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q); + q->limits.max_discard_sectors = max_discard; + if (card->erased_byte == 0 && !mmc_can_discard(card)) + q->limits.discard_zeroes_data = 1; + q->limits.discard_granularity = card->pref_erase << 9; + /* granularity must not be greater than max. discard */ + if (card->pref_erase > max_discard) + q->limits.discard_granularity = 0; + if (mmc_can_secure_erase_trim(card)) + queue_flag_set_unlocked(QUEUE_FLAG_SECDISCARD, q); +} + +/** + * mmc_init_queue - initialise a queue structure. + * @mq: mmc queue + * @card: mmc card to attach this queue + * @lock: queue lock + * @subname: partition subname + * + * Initialise a MMC card request queue. + */ +int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card, + spinlock_t *lock, const char *subname) +{ + struct mmc_host *host = card->host; + u64 limit = BLK_BOUNCE_HIGH; + int ret; + struct mmc_queue_req *mqrq_cur = &mq->mqrq[0]; + struct mmc_queue_req *mqrq_prev = &mq->mqrq[1]; + + if (mmc_dev(host)->dma_mask && *mmc_dev(host)->dma_mask) + limit = (u64)dma_max_pfn(mmc_dev(host)) << PAGE_SHIFT; + + mq->card = card; + mq->queue = blk_init_queue(mmc_request_fn, lock); + if (!mq->queue) + return -ENOMEM; + + mq->mqrq_cur = mqrq_cur; + mq->mqrq_prev = mqrq_prev; + mq->queue->queuedata = mq; + + blk_queue_prep_rq(mq->queue, mmc_prep_request); + queue_flag_set_unlocked(QUEUE_FLAG_NONROT, mq->queue); + queue_flag_clear_unlocked(QUEUE_FLAG_ADD_RANDOM, mq->queue); + if (mmc_can_erase(card)) + mmc_queue_setup_discard(mq->queue, card); + +#ifdef CONFIG_MMC_BLOCK_BOUNCE + if (host->max_segs == 1) { + unsigned int bouncesz; + + bouncesz = MMC_QUEUE_BOUNCESZ; + + if (bouncesz > host->max_req_size) + bouncesz = host->max_req_size; + if (bouncesz > host->max_seg_size) + bouncesz = host->max_seg_size; + if (bouncesz > (host->max_blk_count * 512)) + bouncesz = host->max_blk_count * 512; + + if (bouncesz > 512) { + mqrq_cur->bounce_buf = kmalloc(bouncesz, GFP_KERNEL); + if (!mqrq_cur->bounce_buf) { + pr_warn("%s: unable to allocate bounce cur buffer\n", + mmc_card_name(card)); + } else { + mqrq_prev->bounce_buf = + kmalloc(bouncesz, GFP_KERNEL); + if (!mqrq_prev->bounce_buf) { + pr_warn("%s: unable to allocate bounce prev buffer\n", + mmc_card_name(card)); + kfree(mqrq_cur->bounce_buf); + mqrq_cur->bounce_buf = NULL; + } + } + } + + if (mqrq_cur->bounce_buf && mqrq_prev->bounce_buf) { + blk_queue_bounce_limit(mq->queue, BLK_BOUNCE_ANY); + blk_queue_max_hw_sectors(mq->queue, bouncesz / 512); + blk_queue_max_segments(mq->queue, bouncesz / 512); + blk_queue_max_segment_size(mq->queue, bouncesz); + + mqrq_cur->sg = mmc_alloc_sg(1, &ret); + if (ret) + goto cleanup_queue; + + mqrq_cur->bounce_sg = + mmc_alloc_sg(bouncesz / 512, &ret); + if (ret) + goto cleanup_queue; + + mqrq_prev->sg = mmc_alloc_sg(1, &ret); + if (ret) + goto cleanup_queue; + + mqrq_prev->bounce_sg = + mmc_alloc_sg(bouncesz / 512, &ret); + if (ret) + goto cleanup_queue; + } + } +#endif + + if (!mqrq_cur->bounce_buf && !mqrq_prev->bounce_buf) { + blk_queue_bounce_limit(mq->queue, limit); + blk_queue_max_hw_sectors(mq->queue, + min(host->max_blk_count, host->max_req_size / 512)); + blk_queue_max_segments(mq->queue, host->max_segs); + blk_queue_max_segment_size(mq->queue, host->max_seg_size); + + mqrq_cur->sg = mmc_alloc_sg(host->max_segs, &ret); + if (ret) + goto cleanup_queue; + + + mqrq_prev->sg = mmc_alloc_sg(host->max_segs, &ret); + if (ret) + goto cleanup_queue; + } + + sema_init(&mq->thread_sem, 1); + + mq->thread = kthread_run(mmc_queue_thread, mq, "mmcqd/%d%s", + host->index, subname ? subname : ""); + + if (IS_ERR(mq->thread)) { + ret = PTR_ERR(mq->thread); + goto free_bounce_sg; + } + + return 0; + free_bounce_sg: + kfree(mqrq_cur->bounce_sg); + mqrq_cur->bounce_sg = NULL; + kfree(mqrq_prev->bounce_sg); + mqrq_prev->bounce_sg = NULL; + + cleanup_queue: + kfree(mqrq_cur->sg); + mqrq_cur->sg = NULL; + kfree(mqrq_cur->bounce_buf); + mqrq_cur->bounce_buf = NULL; + + kfree(mqrq_prev->sg); + mqrq_prev->sg = NULL; + kfree(mqrq_prev->bounce_buf); + mqrq_prev->bounce_buf = NULL; + + blk_cleanup_queue(mq->queue); + return ret; +} + +void mmc_cleanup_queue(struct mmc_queue *mq) +{ + struct request_queue *q = mq->queue; + unsigned long flags; + struct mmc_queue_req *mqrq_cur = mq->mqrq_cur; + struct mmc_queue_req *mqrq_prev = mq->mqrq_prev; + + /* Make sure the queue isn't suspended, as that will deadlock */ + mmc_queue_resume(mq); + + /* Then terminate our worker thread */ + kthread_stop(mq->thread); + + /* Empty the queue */ + spin_lock_irqsave(q->queue_lock, flags); + q->queuedata = NULL; + blk_start_queue(q); + spin_unlock_irqrestore(q->queue_lock, flags); + + kfree(mqrq_cur->bounce_sg); + mqrq_cur->bounce_sg = NULL; + + kfree(mqrq_cur->sg); + mqrq_cur->sg = NULL; + + kfree(mqrq_cur->bounce_buf); + mqrq_cur->bounce_buf = NULL; + + kfree(mqrq_prev->bounce_sg); + mqrq_prev->bounce_sg = NULL; + + kfree(mqrq_prev->sg); + mqrq_prev->sg = NULL; + + kfree(mqrq_prev->bounce_buf); + mqrq_prev->bounce_buf = NULL; + + mq->card = NULL; +} +EXPORT_SYMBOL(mmc_cleanup_queue); + +int mmc_packed_init(struct mmc_queue *mq, struct mmc_card *card) +{ + struct mmc_queue_req *mqrq_cur = &mq->mqrq[0]; + struct mmc_queue_req *mqrq_prev = &mq->mqrq[1]; + int ret = 0; + + + mqrq_cur->packed = kzalloc(sizeof(struct mmc_packed), GFP_KERNEL); + if (!mqrq_cur->packed) { + pr_warn("%s: unable to allocate packed cmd for mqrq_cur\n", + mmc_card_name(card)); + ret = -ENOMEM; + goto out; + } + + mqrq_prev->packed = kzalloc(sizeof(struct mmc_packed), GFP_KERNEL); + if (!mqrq_prev->packed) { + pr_warn("%s: unable to allocate packed cmd for mqrq_prev\n", + mmc_card_name(card)); + kfree(mqrq_cur->packed); + mqrq_cur->packed = NULL; + ret = -ENOMEM; + goto out; + } + + INIT_LIST_HEAD(&mqrq_cur->packed->list); + INIT_LIST_HEAD(&mqrq_prev->packed->list); + +out: + return ret; +} + +void mmc_packed_clean(struct mmc_queue *mq) +{ + struct mmc_queue_req *mqrq_cur = &mq->mqrq[0]; + struct mmc_queue_req *mqrq_prev = &mq->mqrq[1]; + + kfree(mqrq_cur->packed); + mqrq_cur->packed = NULL; + kfree(mqrq_prev->packed); + mqrq_prev->packed = NULL; +} + +/** + * mmc_queue_suspend - suspend a MMC request queue + * @mq: MMC queue to suspend + * + * Stop the block request queue, and wait for our thread to + * complete any outstanding requests. This ensures that we + * won't suspend while a request is being processed. + */ +void mmc_queue_suspend(struct mmc_queue *mq) +{ + struct request_queue *q = mq->queue; + unsigned long flags; + + if (!(mq->flags & MMC_QUEUE_SUSPENDED)) { + mq->flags |= MMC_QUEUE_SUSPENDED; + + spin_lock_irqsave(q->queue_lock, flags); + blk_stop_queue(q); + spin_unlock_irqrestore(q->queue_lock, flags); + + down(&mq->thread_sem); + } +} + +/** + * mmc_queue_resume - resume a previously suspended MMC request queue + * @mq: MMC queue to resume + */ +void mmc_queue_resume(struct mmc_queue *mq) +{ + struct request_queue *q = mq->queue; + unsigned long flags; + + if (mq->flags & MMC_QUEUE_SUSPENDED) { + mq->flags &= ~MMC_QUEUE_SUSPENDED; + + up(&mq->thread_sem); + + spin_lock_irqsave(q->queue_lock, flags); + blk_start_queue(q); + spin_unlock_irqrestore(q->queue_lock, flags); + } +} + +static unsigned int mmc_queue_packed_map_sg(struct mmc_queue *mq, + struct mmc_packed *packed, + struct scatterlist *sg, + enum mmc_packed_type cmd_type) +{ + struct scatterlist *__sg = sg; + unsigned int sg_len = 0; + struct request *req; + + if (mmc_packed_wr(cmd_type)) { + unsigned int hdr_sz = mmc_large_sector(mq->card) ? 4096 : 512; + unsigned int max_seg_sz = queue_max_segment_size(mq->queue); + unsigned int len, remain, offset = 0; + u8 *buf = (u8 *)packed->cmd_hdr; + + remain = hdr_sz; + do { + len = min(remain, max_seg_sz); + sg_set_buf(__sg, buf + offset, len); + offset += len; + remain -= len; + (__sg++)->page_link &= ~0x02; + sg_len++; + } while (remain); + } + + list_for_each_entry(req, &packed->list, queuelist) { + sg_len += blk_rq_map_sg(mq->queue, req, __sg); + __sg = sg + (sg_len - 1); + (__sg++)->page_link &= ~0x02; + } + sg_mark_end(sg + (sg_len - 1)); + return sg_len; +} + +/* + * Prepare the sg list(s) to be handed of to the host driver + */ +unsigned int mmc_queue_map_sg(struct mmc_queue *mq, struct mmc_queue_req *mqrq) +{ + unsigned int sg_len; + size_t buflen; + struct scatterlist *sg; + enum mmc_packed_type cmd_type; + int i; + + cmd_type = mqrq->cmd_type; + + if (!mqrq->bounce_buf) { + if (mmc_packed_cmd(cmd_type)) + return mmc_queue_packed_map_sg(mq, mqrq->packed, + mqrq->sg, cmd_type); + else + return blk_rq_map_sg(mq->queue, mqrq->req, mqrq->sg); + } + + BUG_ON(!mqrq->bounce_sg); + + if (mmc_packed_cmd(cmd_type)) + sg_len = mmc_queue_packed_map_sg(mq, mqrq->packed, + mqrq->bounce_sg, cmd_type); + else + sg_len = blk_rq_map_sg(mq->queue, mqrq->req, mqrq->bounce_sg); + + mqrq->bounce_sg_len = sg_len; + + buflen = 0; + for_each_sg(mqrq->bounce_sg, sg, sg_len, i) + buflen += sg->length; + + sg_init_one(mqrq->sg, mqrq->bounce_buf, buflen); + + return 1; +} + +/* + * If writing, bounce the data to the buffer before the request + * is sent to the host driver + */ +void mmc_queue_bounce_pre(struct mmc_queue_req *mqrq) +{ + if (!mqrq->bounce_buf) + return; + + if (rq_data_dir(mqrq->req) != WRITE) + return; + + sg_copy_to_buffer(mqrq->bounce_sg, mqrq->bounce_sg_len, + mqrq->bounce_buf, mqrq->sg[0].length); +} + +/* + * If reading, bounce the data from the buffer after the request + * has been handled by the host driver + */ +void mmc_queue_bounce_post(struct mmc_queue_req *mqrq) +{ + if (!mqrq->bounce_buf) + return; + + if (rq_data_dir(mqrq->req) != READ) + return; + + sg_copy_from_buffer(mqrq->bounce_sg, mqrq->bounce_sg_len, + mqrq->bounce_buf, mqrq->sg[0].length); +} |