diff options
Diffstat (limited to 'block/ll_rw_blk.c')
-rw-r--r-- | block/ll_rw_blk.c | 274 |
1 files changed, 153 insertions, 121 deletions
diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c index c847e17e5ca..0f82e12f7b6 100644 --- a/block/ll_rw_blk.c +++ b/block/ll_rw_blk.c @@ -56,11 +56,6 @@ static kmem_cache_t *requestq_cachep; */ static kmem_cache_t *iocontext_cachep; -static wait_queue_head_t congestion_wqh[2] = { - __WAIT_QUEUE_HEAD_INITIALIZER(congestion_wqh[0]), - __WAIT_QUEUE_HEAD_INITIALIZER(congestion_wqh[1]) - }; - /* * Controlling structure to kblockd */ @@ -112,35 +107,6 @@ static void blk_queue_congestion_threshold(struct request_queue *q) q->nr_congestion_off = nr; } -/* - * A queue has just exitted congestion. Note this in the global counter of - * congested queues, and wake up anyone who was waiting for requests to be - * put back. - */ -static void clear_queue_congested(request_queue_t *q, int rw) -{ - enum bdi_state bit; - wait_queue_head_t *wqh = &congestion_wqh[rw]; - - bit = (rw == WRITE) ? BDI_write_congested : BDI_read_congested; - clear_bit(bit, &q->backing_dev_info.state); - smp_mb__after_clear_bit(); - if (waitqueue_active(wqh)) - wake_up(wqh); -} - -/* - * A queue has just entered congestion. Flag that in the queue's VM-visible - * state flags and increment the global gounter of congested queues. - */ -static void set_queue_congested(request_queue_t *q, int rw) -{ - enum bdi_state bit; - - bit = (rw == WRITE) ? BDI_write_congested : BDI_read_congested; - set_bit(bit, &q->backing_dev_info.state); -} - /** * blk_get_backing_dev_info - get the address of a queue's backing_dev_info * @bdev: device @@ -159,7 +125,6 @@ struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev) ret = &q->backing_dev_info; return ret; } - EXPORT_SYMBOL(blk_get_backing_dev_info); void blk_queue_activity_fn(request_queue_t *q, activity_fn *fn, void *data) @@ -167,7 +132,6 @@ void blk_queue_activity_fn(request_queue_t *q, activity_fn *fn, void *data) q->activity_fn = fn; q->activity_data = data; } - EXPORT_SYMBOL(blk_queue_activity_fn); /** @@ -2067,7 +2031,7 @@ static void __freed_request(request_queue_t *q, int rw) struct request_list *rl = &q->rq; if (rl->count[rw] < queue_congestion_off_threshold(q)) - clear_queue_congested(q, rw); + blk_clear_queue_congested(q, rw); if (rl->count[rw] + 1 <= q->nr_requests) { if (waitqueue_active(&rl->wait[rw])) @@ -2137,7 +2101,7 @@ static struct request *get_request(request_queue_t *q, int rw, struct bio *bio, } } } - set_queue_congested(q, rw); + blk_set_queue_congested(q, rw); } /* @@ -2358,6 +2322,84 @@ void blk_insert_request(request_queue_t *q, struct request *rq, EXPORT_SYMBOL(blk_insert_request); +static int __blk_rq_unmap_user(struct bio *bio) +{ + int ret = 0; + + if (bio) { + if (bio_flagged(bio, BIO_USER_MAPPED)) + bio_unmap_user(bio); + else + ret = bio_uncopy_user(bio); + } + + return ret; +} + +static int __blk_rq_map_user(request_queue_t *q, struct request *rq, + void __user *ubuf, unsigned int len) +{ + unsigned long uaddr; + struct bio *bio, *orig_bio; + int reading, ret; + + reading = rq_data_dir(rq) == READ; + + /* + * if alignment requirement is satisfied, map in user pages for + * direct dma. else, set up kernel bounce buffers + */ + uaddr = (unsigned long) ubuf; + if (!(uaddr & queue_dma_alignment(q)) && !(len & queue_dma_alignment(q))) + bio = bio_map_user(q, NULL, uaddr, len, reading); + else + bio = bio_copy_user(q, uaddr, len, reading); + + if (IS_ERR(bio)) { + return PTR_ERR(bio); + } + + orig_bio = bio; + blk_queue_bounce(q, &bio); + /* + * We link the bounce buffer in and could have to traverse it + * later so we have to get a ref to prevent it from being freed + */ + bio_get(bio); + + /* + * for most (all? don't know of any) queues we could + * skip grabbing the queue lock here. only drivers with + * funky private ->back_merge_fn() function could be + * problematic. + */ + spin_lock_irq(q->queue_lock); + if (!rq->bio) + blk_rq_bio_prep(q, rq, bio); + else if (!q->back_merge_fn(q, rq, bio)) { + ret = -EINVAL; + spin_unlock_irq(q->queue_lock); + goto unmap_bio; + } else { + rq->biotail->bi_next = bio; + rq->biotail = bio; + + rq->nr_sectors += bio_sectors(bio); + rq->hard_nr_sectors = rq->nr_sectors; + rq->data_len += bio->bi_size; + } + spin_unlock_irq(q->queue_lock); + + return bio->bi_size; + +unmap_bio: + /* if it was boucned we must call the end io function */ + bio_endio(bio, bio->bi_size, 0); + __blk_rq_unmap_user(orig_bio); + bio_put(bio); + return ret; +} + /** * blk_rq_map_user - map user data to a request, for REQ_BLOCK_PC usage * @q: request queue where request should be inserted @@ -2379,42 +2421,44 @@ EXPORT_SYMBOL(blk_insert_request); * unmapping. */ int blk_rq_map_user(request_queue_t *q, struct request *rq, void __user *ubuf, - unsigned int len) + unsigned long len) { - unsigned long uaddr; - struct bio *bio; - int reading; + unsigned long bytes_read = 0; + int ret; if (len > (q->max_hw_sectors << 9)) return -EINVAL; if (!len || !ubuf) return -EINVAL; - reading = rq_data_dir(rq) == READ; + while (bytes_read != len) { + unsigned long map_len, end, start; - /* - * if alignment requirement is satisfied, map in user pages for - * direct dma. else, set up kernel bounce buffers - */ - uaddr = (unsigned long) ubuf; - if (!(uaddr & queue_dma_alignment(q)) && !(len & queue_dma_alignment(q))) - bio = bio_map_user(q, NULL, uaddr, len, reading); - else - bio = bio_copy_user(q, uaddr, len, reading); + map_len = min_t(unsigned long, len - bytes_read, BIO_MAX_SIZE); + end = ((unsigned long)ubuf + map_len + PAGE_SIZE - 1) + >> PAGE_SHIFT; + start = (unsigned long)ubuf >> PAGE_SHIFT; - if (!IS_ERR(bio)) { - rq->bio = rq->biotail = bio; - blk_rq_bio_prep(q, rq, bio); + /* + * A bad offset could cause us to require BIO_MAX_PAGES + 1 + * pages. If this happens we just lower the requested + * mapping len by a page so that we can fit + */ + if (end - start > BIO_MAX_PAGES) + map_len -= PAGE_SIZE; - rq->buffer = rq->data = NULL; - rq->data_len = len; - return 0; + ret = __blk_rq_map_user(q, rq, ubuf, map_len); + if (ret < 0) + goto unmap_rq; + bytes_read += ret; + ubuf += ret; } - /* - * bio is the err-ptr - */ - return PTR_ERR(bio); + rq->buffer = rq->data = NULL; + return 0; +unmap_rq: + blk_rq_unmap_user(rq); + return ret; } EXPORT_SYMBOL(blk_rq_map_user); @@ -2440,7 +2484,7 @@ EXPORT_SYMBOL(blk_rq_map_user); * unmapping. */ int blk_rq_map_user_iov(request_queue_t *q, struct request *rq, - struct sg_iovec *iov, int iov_count) + struct sg_iovec *iov, int iov_count, unsigned int len) { struct bio *bio; @@ -2454,10 +2498,15 @@ int blk_rq_map_user_iov(request_queue_t *q, struct request *rq, if (IS_ERR(bio)) return PTR_ERR(bio); - rq->bio = rq->biotail = bio; + if (bio->bi_size != len) { + bio_endio(bio, bio->bi_size, 0); + bio_unmap_user(bio); + return -EINVAL; + } + + bio_get(bio); blk_rq_bio_prep(q, rq, bio); rq->buffer = rq->data = NULL; - rq->data_len = bio->bi_size; return 0; } @@ -2465,23 +2514,26 @@ EXPORT_SYMBOL(blk_rq_map_user_iov); /** * blk_rq_unmap_user - unmap a request with user data - * @bio: bio to be unmapped - * @ulen: length of user buffer + * @rq: rq to be unmapped * * Description: - * Unmap a bio previously mapped by blk_rq_map_user(). + * Unmap a rq previously mapped by blk_rq_map_user(). + * rq->bio must be set to the original head of the request. */ -int blk_rq_unmap_user(struct bio *bio, unsigned int ulen) +int blk_rq_unmap_user(struct request *rq) { - int ret = 0; + struct bio *bio, *mapped_bio; - if (bio) { - if (bio_flagged(bio, BIO_USER_MAPPED)) - bio_unmap_user(bio); + while ((bio = rq->bio)) { + if (bio_flagged(bio, BIO_BOUNCED)) + mapped_bio = bio->bi_private; else - ret = bio_uncopy_user(bio); - } + mapped_bio = bio; + __blk_rq_unmap_user(mapped_bio); + rq->bio = bio->bi_next; + bio_put(bio); + } return 0; } @@ -2512,11 +2564,8 @@ int blk_rq_map_kern(request_queue_t *q, struct request *rq, void *kbuf, if (rq_data_dir(rq) == WRITE) bio->bi_rw |= (1 << BIO_RW); - rq->bio = rq->biotail = bio; blk_rq_bio_prep(q, rq, bio); - rq->buffer = rq->data = NULL; - rq->data_len = len; return 0; } @@ -2755,41 +2804,6 @@ void blk_end_sync_rq(struct request *rq, int error) } EXPORT_SYMBOL(blk_end_sync_rq); -/** - * blk_congestion_wait - wait for a queue to become uncongested - * @rw: READ or WRITE - * @timeout: timeout in jiffies - * - * Waits for up to @timeout jiffies for a queue (any queue) to exit congestion. - * If no queues are congested then just wait for the next request to be - * returned. - */ -long blk_congestion_wait(int rw, long timeout) -{ - long ret; - DEFINE_WAIT(wait); - wait_queue_head_t *wqh = &congestion_wqh[rw]; - - prepare_to_wait(wqh, &wait, TASK_UNINTERRUPTIBLE); - ret = io_schedule_timeout(timeout); - finish_wait(wqh, &wait); - return ret; -} - -EXPORT_SYMBOL(blk_congestion_wait); - -/** - * blk_congestion_end - wake up sleepers on a congestion queue - * @rw: READ or WRITE - */ -void blk_congestion_end(int rw) -{ - wait_queue_head_t *wqh = &congestion_wqh[rw]; - - if (waitqueue_active(wqh)) - wake_up(wqh); -} - /* * Has to be called with the request spinlock acquired */ @@ -3070,6 +3084,7 @@ void generic_make_request(struct bio *bio) { request_queue_t *q; sector_t maxsector; + sector_t old_sector; int ret, nr_sectors = bio_sectors(bio); dev_t old_dev; @@ -3098,7 +3113,7 @@ void generic_make_request(struct bio *bio) * NOTE: we don't repeat the blk_size check for each new device. * Stacking drivers are expected to know what they are doing. */ - maxsector = -1; + old_sector = -1; old_dev = 0; do { char b[BDEVNAME_SIZE]; @@ -3132,15 +3147,31 @@ end_io: */ blk_partition_remap(bio); - if (maxsector != -1) + if (old_sector != -1) blk_add_trace_remap(q, bio, old_dev, bio->bi_sector, - maxsector); + old_sector); blk_add_trace_bio(q, bio, BLK_TA_QUEUE); - maxsector = bio->bi_sector; + old_sector = bio->bi_sector; old_dev = bio->bi_bdev->bd_dev; + maxsector = bio->bi_bdev->bd_inode->i_size >> 9; + if (maxsector) { + sector_t sector = bio->bi_sector; + + if (maxsector < nr_sectors || + maxsector - nr_sectors < sector) { + /* + * This may well happen - partitions are not + * checked to make sure they are within the size + * of the whole device. + */ + handle_bad_sector(bio); + goto end_io; + } + } + ret = q->make_request_fn(q, bio); } while (ret); } @@ -3549,6 +3580,7 @@ void blk_rq_bio_prep(request_queue_t *q, struct request *rq, struct bio *bio) rq->hard_cur_sectors = rq->current_nr_sectors; rq->hard_nr_sectors = rq->nr_sectors = bio_sectors(bio); rq->buffer = bio_data(bio); + rq->data_len = bio->bi_size; rq->bio = rq->biotail = bio; } @@ -3765,14 +3797,14 @@ queue_requests_store(struct request_queue *q, const char *page, size_t count) blk_queue_congestion_threshold(q); if (rl->count[READ] >= queue_congestion_on_threshold(q)) - set_queue_congested(q, READ); + blk_set_queue_congested(q, READ); else if (rl->count[READ] < queue_congestion_off_threshold(q)) - clear_queue_congested(q, READ); + blk_clear_queue_congested(q, READ); if (rl->count[WRITE] >= queue_congestion_on_threshold(q)) - set_queue_congested(q, WRITE); + blk_set_queue_congested(q, WRITE); else if (rl->count[WRITE] < queue_congestion_off_threshold(q)) - clear_queue_congested(q, WRITE); + blk_clear_queue_congested(q, WRITE); if (rl->count[READ] >= q->nr_requests) { blk_set_queue_full(q, READ); |