diff options
Diffstat (limited to 'drivers/mmc/card/queue.c')
| -rw-r--r-- | drivers/mmc/card/queue.c | 191 |
1 files changed, 177 insertions, 14 deletions
diff --git a/drivers/mmc/card/queue.c b/drivers/mmc/card/queue.c index dd97bc79840..4fb2089dc69 100644 --- a/drivers/mmc/card/queue.c +++ b/drivers/mmc/card/queue.c @@ -17,6 +17,8 @@ #include <linux/mmc/host.h> #include "queue.h" +#define MMC_QUEUE_BOUNCESZ 65536 + #define MMC_QUEUE_SUSPENDED (1 << 0) /* @@ -118,6 +120,7 @@ int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card, spinlock_t *lock struct mmc_host *host = card->host; u64 limit = BLK_BOUNCE_HIGH; int ret; + unsigned int bouncesz; if (mmc_dev(host)->dma_mask && *mmc_dev(host)->dma_mask) limit = *mmc_dev(host)->dma_mask; @@ -127,21 +130,61 @@ int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card, spinlock_t *lock if (!mq->queue) return -ENOMEM; - blk_queue_prep_rq(mq->queue, mmc_prep_request); - blk_queue_bounce_limit(mq->queue, limit); - blk_queue_max_sectors(mq->queue, host->max_req_size / 512); - blk_queue_max_phys_segments(mq->queue, host->max_phys_segs); - blk_queue_max_hw_segments(mq->queue, host->max_hw_segs); - blk_queue_max_segment_size(mq->queue, host->max_seg_size); - mq->queue->queuedata = mq; mq->req = NULL; - mq->sg = kmalloc(sizeof(struct scatterlist) * host->max_phys_segs, - GFP_KERNEL); - if (!mq->sg) { - ret = -ENOMEM; - goto cleanup_queue; + blk_queue_prep_rq(mq->queue, mmc_prep_request); + +#ifdef CONFIG_MMC_BLOCK_BOUNCE + if (host->max_hw_segs == 1) { + 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; + + mq->bounce_buf = kmalloc(bouncesz, GFP_KERNEL); + if (!mq->bounce_buf) { + printk(KERN_WARNING "%s: unable to allocate " + "bounce buffer\n", mmc_card_name(card)); + } else { + blk_queue_bounce_limit(mq->queue, BLK_BOUNCE_HIGH); + blk_queue_max_sectors(mq->queue, bouncesz / 512); + blk_queue_max_phys_segments(mq->queue, bouncesz / 512); + blk_queue_max_hw_segments(mq->queue, bouncesz / 512); + blk_queue_max_segment_size(mq->queue, bouncesz); + + mq->sg = kmalloc(sizeof(struct scatterlist), + GFP_KERNEL); + if (!mq->sg) { + ret = -ENOMEM; + goto free_bounce_buf; + } + + mq->bounce_sg = kmalloc(sizeof(struct scatterlist) * + bouncesz / 512, GFP_KERNEL); + if (!mq->bounce_sg) { + ret = -ENOMEM; + goto free_sg; + } + } + } +#endif + + if (!mq->bounce_buf) { + blk_queue_bounce_limit(mq->queue, limit); + blk_queue_max_sectors(mq->queue, host->max_req_size / 512); + blk_queue_max_phys_segments(mq->queue, host->max_phys_segs); + blk_queue_max_hw_segments(mq->queue, host->max_hw_segs); + blk_queue_max_segment_size(mq->queue, host->max_seg_size); + + mq->sg = kmalloc(sizeof(struct scatterlist) * + host->max_phys_segs, GFP_KERNEL); + if (!mq->sg) { + ret = -ENOMEM; + goto cleanup_queue; + } } init_MUTEX(&mq->thread_sem); @@ -149,14 +192,21 @@ int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card, spinlock_t *lock mq->thread = kthread_run(mmc_queue_thread, mq, "mmcqd"); if (IS_ERR(mq->thread)) { ret = PTR_ERR(mq->thread); - goto free_sg; + goto free_bounce_sg; } return 0; - + free_bounce_sg: + if (mq->bounce_sg) + kfree(mq->bounce_sg); + mq->bounce_sg = NULL; free_sg: kfree(mq->sg); mq->sg = NULL; + free_bounce_buf: + if (mq->bounce_buf) + kfree(mq->bounce_buf); + mq->bounce_buf = NULL; cleanup_queue: blk_cleanup_queue(mq->queue); return ret; @@ -178,9 +228,17 @@ void mmc_cleanup_queue(struct mmc_queue *mq) /* Then terminate our worker thread */ kthread_stop(mq->thread); + if (mq->bounce_sg) + kfree(mq->bounce_sg); + mq->bounce_sg = NULL; + kfree(mq->sg); mq->sg = NULL; + if (mq->bounce_buf) + kfree(mq->bounce_buf); + mq->bounce_buf = NULL; + blk_cleanup_queue(mq->queue); mq->card = NULL; @@ -231,3 +289,108 @@ void mmc_queue_resume(struct mmc_queue *mq) } } +static void copy_sg(struct scatterlist *dst, unsigned int dst_len, + struct scatterlist *src, unsigned int src_len) +{ + unsigned int chunk; + char *dst_buf, *src_buf; + unsigned int dst_size, src_size; + + dst_buf = NULL; + src_buf = NULL; + dst_size = 0; + src_size = 0; + + while (src_len) { + BUG_ON(dst_len == 0); + + if (dst_size == 0) { + dst_buf = page_address(dst->page) + dst->offset; + dst_size = dst->length; + } + + if (src_size == 0) { + src_buf = page_address(src->page) + src->offset; + src_size = src->length; + } + + chunk = min(dst_size, src_size); + + memcpy(dst_buf, src_buf, chunk); + + dst_buf += chunk; + src_buf += chunk; + dst_size -= chunk; + src_size -= chunk; + + if (dst_size == 0) { + dst++; + dst_len--; + } + + if (src_size == 0) { + src++; + src_len--; + } + } +} + +unsigned int mmc_queue_map_sg(struct mmc_queue *mq) +{ + unsigned int sg_len; + + if (!mq->bounce_buf) + return blk_rq_map_sg(mq->queue, mq->req, mq->sg); + + BUG_ON(!mq->bounce_sg); + + sg_len = blk_rq_map_sg(mq->queue, mq->req, mq->bounce_sg); + + mq->bounce_sg_len = sg_len; + + /* + * Shortcut in the event we only get a single entry. + */ + if (sg_len == 1) { + memcpy(mq->sg, mq->bounce_sg, sizeof(struct scatterlist)); + return 1; + } + + mq->sg[0].page = virt_to_page(mq->bounce_buf); + mq->sg[0].offset = offset_in_page(mq->bounce_buf); + mq->sg[0].length = 0; + + while (sg_len) { + mq->sg[0].length += mq->bounce_sg[sg_len - 1].length; + sg_len--; + } + + return 1; +} + +void mmc_queue_bounce_pre(struct mmc_queue *mq) +{ + if (!mq->bounce_buf) + return; + + if (mq->bounce_sg_len == 1) + return; + if (rq_data_dir(mq->req) != WRITE) + return; + + copy_sg(mq->sg, 1, mq->bounce_sg, mq->bounce_sg_len); +} + +void mmc_queue_bounce_post(struct mmc_queue *mq) +{ + if (!mq->bounce_buf) + return; + + if (mq->bounce_sg_len == 1) + return; + if (rq_data_dir(mq->req) != READ) + return; + + copy_sg(mq->bounce_sg, mq->bounce_sg_len, mq->sg, 1); +} + |