diff options
Diffstat (limited to 'block/ll_rw_blk.c')
-rw-r--r-- | block/ll_rw_blk.c | 86 |
1 files changed, 45 insertions, 41 deletions
diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c index 8e27d0ab0d7..0ef2971a9e8 100644 --- a/block/ll_rw_blk.c +++ b/block/ll_rw_blk.c @@ -304,6 +304,7 @@ static inline void rq_init(request_queue_t *q, struct request *rq) * blk_queue_ordered - does this queue support ordered writes * @q: the request queue * @ordered: one of QUEUE_ORDERED_* + * @prepare_flush_fn: rq setup helper for cache flush ordered writes * * Description: * For journalled file systems, doing ordered writes on a commit @@ -332,6 +333,7 @@ int blk_queue_ordered(request_queue_t *q, unsigned ordered, return -EINVAL; } + q->ordered = ordered; q->next_ordered = ordered; q->prepare_flush_fn = prepare_flush_fn; @@ -452,7 +454,7 @@ static void queue_flush(request_queue_t *q, unsigned which) rq->end_io = end_io; q->prepare_flush_fn(q, rq); - __elv_add_request(q, rq, ELEVATOR_INSERT_FRONT, 0); + elv_insert(q, rq, ELEVATOR_INSERT_FRONT); } static inline struct request *start_ordered(request_queue_t *q, @@ -488,7 +490,7 @@ static inline struct request *start_ordered(request_queue_t *q, else q->ordseq |= QUEUE_ORDSEQ_POSTFLUSH; - __elv_add_request(q, rq, ELEVATOR_INSERT_FRONT, 0); + elv_insert(q, rq, ELEVATOR_INSERT_FRONT); if (q->ordered & QUEUE_ORDERED_PREFLUSH) { queue_flush(q, QUEUE_ORDERED_PREFLUSH); @@ -506,7 +508,7 @@ static inline struct request *start_ordered(request_queue_t *q, int blk_do_ordered(request_queue_t *q, struct request **rqp) { - struct request *rq = *rqp, *allowed_rq; + struct request *rq = *rqp; int is_barrier = blk_fs_request(rq) && blk_barrier_rq(rq); if (!q->ordseq) { @@ -530,32 +532,26 @@ int blk_do_ordered(request_queue_t *q, struct request **rqp) } } + /* + * Ordered sequence in progress + */ + + /* Special requests are not subject to ordering rules. */ + if (!blk_fs_request(rq) && + rq != &q->pre_flush_rq && rq != &q->post_flush_rq) + return 1; + if (q->ordered & QUEUE_ORDERED_TAG) { + /* Ordered by tag. Blocking the next barrier is enough. */ if (is_barrier && rq != &q->bar_rq) *rqp = NULL; - return 1; - } - - switch (blk_ordered_cur_seq(q)) { - case QUEUE_ORDSEQ_PREFLUSH: - allowed_rq = &q->pre_flush_rq; - break; - case QUEUE_ORDSEQ_BAR: - allowed_rq = &q->bar_rq; - break; - case QUEUE_ORDSEQ_POSTFLUSH: - allowed_rq = &q->post_flush_rq; - break; - default: - allowed_rq = NULL; - break; + } else { + /* Ordered by draining. Wait for turn. */ + WARN_ON(blk_ordered_req_seq(rq) < blk_ordered_cur_seq(q)); + if (blk_ordered_req_seq(rq) > blk_ordered_cur_seq(q)) + *rqp = NULL; } - if (rq != allowed_rq && - (blk_fs_request(rq) || rq == &q->pre_flush_rq || - rq == &q->post_flush_rq)) - *rqp = NULL; - return 1; } @@ -629,26 +625,31 @@ static inline int ordered_bio_endio(struct request *rq, struct bio *bio, * Different hardware can have different requirements as to what pages * it can do I/O directly to. A low level driver can call * blk_queue_bounce_limit to have lower memory pages allocated as bounce - * buffers for doing I/O to pages residing above @page. By default - * the block layer sets this to the highest numbered "low" memory page. + * buffers for doing I/O to pages residing above @page. **/ void blk_queue_bounce_limit(request_queue_t *q, u64 dma_addr) { unsigned long bounce_pfn = dma_addr >> PAGE_SHIFT; - - /* - * set appropriate bounce gfp mask -- unfortunately we don't have a - * full 4GB zone, so we have to resort to low memory for any bounces. - * ISA has its own < 16MB zone. - */ - if (bounce_pfn < blk_max_low_pfn) { - BUG_ON(dma_addr < BLK_BOUNCE_ISA); + int dma = 0; + + q->bounce_gfp = GFP_NOIO; +#if BITS_PER_LONG == 64 + /* Assume anything <= 4GB can be handled by IOMMU. + Actually some IOMMUs can handle everything, but I don't + know of a way to test this here. */ + if (bounce_pfn < (0xffffffff>>PAGE_SHIFT)) + dma = 1; + q->bounce_pfn = max_low_pfn; +#else + if (bounce_pfn < blk_max_low_pfn) + dma = 1; + q->bounce_pfn = bounce_pfn; +#endif + if (dma) { init_emergency_isa_pool(); q->bounce_gfp = GFP_NOIO | GFP_DMA; - } else - q->bounce_gfp = GFP_NOIO; - - q->bounce_pfn = bounce_pfn; + q->bounce_pfn = bounce_pfn; + } } EXPORT_SYMBOL(blk_queue_bounce_limit); @@ -662,7 +663,7 @@ EXPORT_SYMBOL(blk_queue_bounce_limit); * Enables a low level driver to set an upper limit on the size of * received requests. **/ -void blk_queue_max_sectors(request_queue_t *q, unsigned short max_sectors) +void blk_queue_max_sectors(request_queue_t *q, unsigned int max_sectors) { if ((max_sectors << 9) < PAGE_CACHE_SIZE) { max_sectors = 1 << (PAGE_CACHE_SHIFT - 9); @@ -2577,6 +2578,8 @@ void disk_round_stats(struct gendisk *disk) disk->stamp = now; } +EXPORT_SYMBOL_GPL(disk_round_stats); + /* * queue lock must be held */ @@ -2632,6 +2635,7 @@ EXPORT_SYMBOL(blk_put_request); /** * blk_end_sync_rq - executes a completion event on a request * @rq: request to complete + * @error: end io status of the request */ void blk_end_sync_rq(struct request *rq, int error) { @@ -3153,7 +3157,7 @@ static int __end_that_request_first(struct request *req, int uptodate, if (blk_fs_request(req) && req->rq_disk) { const int rw = rq_data_dir(req); - __disk_stat_add(req->rq_disk, sectors[rw], nr_bytes >> 9); + disk_stat_add(req->rq_disk, sectors[rw], nr_bytes >> 9); } total_bytes = bio_nbytes = 0; @@ -3448,7 +3452,7 @@ int __init blk_dev_init(void) iocontext_cachep = kmem_cache_create("blkdev_ioc", sizeof(struct io_context), 0, SLAB_PANIC, NULL, NULL); - for (i = 0; i < NR_CPUS; i++) + for_each_cpu(i) INIT_LIST_HEAD(&per_cpu(blk_cpu_done, i)); open_softirq(BLOCK_SOFTIRQ, blk_done_softirq, NULL); |