diff options
| -rw-r--r-- | fs/btrfs/volumes.c | 159 |
1 files changed, 131 insertions, 28 deletions
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index a8adf26..eaaf0bf 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -4217,6 +4217,113 @@ static noinline void schedule_bio(struct btrfs_root *root, &device->work); } +static int bio_size_ok(struct block_device *bdev, struct bio *bio, + sector_t sector) +{ + struct bio_vec *prev; + struct request_queue *q = bdev_get_queue(bdev); + unsigned short max_sectors = queue_max_sectors(q); + struct bvec_merge_data bvm = { + .bi_bdev = bdev, + .bi_sector = sector, + .bi_rw = bio->bi_rw, + }; + + if (bio->bi_vcnt == 0) { + WARN_ON(1); + return 1; + } + + prev = &bio->bi_io_vec[bio->bi_vcnt - 1]; + if ((bio->bi_size >> 9) > max_sectors) + return 0; + + if (!q->merge_bvec_fn) + return 1; + + bvm.bi_size = bio->bi_size - prev->bv_len; + if (q->merge_bvec_fn(q, &bvm, prev) < prev->bv_len) + return 0; + return 1; +} + +static void submit_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio, + struct bio *bio, u64 physical, int dev_nr, + int rw, int async) +{ + struct btrfs_device *dev = bbio->stripes[dev_nr].dev; + + bio->bi_private = bbio; + bio->bi_private = merge_stripe_index_into_bio_private( + bio->bi_private, (unsigned int)dev_nr); + bio->bi_end_io = btrfs_end_bio; + bio->bi_sector = physical >> 9; +#ifdef DEBUG + { + struct rcu_string *name; + + rcu_read_lock(); + name = rcu_dereference(dev->name); + pr_debug("btrfs_map_bio: rw %d, secor=%llu, dev=%lu " + "(%s id %llu), size=%u\n", rw, + (u64)bio->bi_sector, (u_long)dev->bdev->bd_dev, + name->str, dev->devid, bio->bi_size); + rcu_read_unlock(); + } +#endif + bio->bi_bdev = dev->bdev; + if (async) + schedule_bio(root, dev, rw, bio); + else + btrfsic_submit_bio(rw, bio); +} + +static int breakup_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio, + struct bio *first_bio, struct btrfs_device *dev, + int dev_nr, int rw, int async) +{ + struct bio_vec *bvec = first_bio->bi_io_vec; + struct bio *bio; + int nr_vecs = bio_get_nr_vecs(dev->bdev); + u64 physical = bbio->stripes[dev_nr].physical; + +again: + bio = btrfs_bio_alloc(dev->bdev, physical >> 9, nr_vecs, GFP_NOFS); + if (!bio) + return -ENOMEM; + + while (bvec <= (first_bio->bi_io_vec + first_bio->bi_vcnt - 1)) { + if (bio_add_page(bio, bvec->bv_page, bvec->bv_len, + bvec->bv_offset) < bvec->bv_len) { + u64 len = bio->bi_size; + + atomic_inc(&bbio->stripes_pending); + submit_stripe_bio(root, bbio, bio, physical, dev_nr, + rw, async); + physical += len; + goto again; + } + bvec++; + } + + submit_stripe_bio(root, bbio, bio, physical, dev_nr, rw, async); + return 0; +} + +static void bbio_error(struct btrfs_bio *bbio, struct bio *bio, u64 logical) +{ + atomic_inc(&bbio->error); + if (atomic_dec_and_test(&bbio->stripes_pending)) { + bio->bi_private = bbio->private; + bio->bi_end_io = bbio->end_io; + bio->bi_bdev = (struct block_device *) + (unsigned long)bbio->mirror_num; + bio->bi_sector = logical >> 9; + kfree(bbio); + bio_endio(bio, -EIO); + } +} + int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio, int mirror_num, int async_submit) { @@ -4255,40 +4362,36 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio, atomic_set(&bbio->stripes_pending, bbio->num_stripes); while (dev_nr < total_devs) { + dev = bbio->stripes[dev_nr].dev; + if (!dev || !dev->bdev || (rw & WRITE && !dev->writeable)) { + bbio_error(bbio, first_bio, logical); + dev_nr++; + continue; + } + + /* + * Check and see if we're ok with this bio based on it's size + * and offset with the given device. + */ + if (!bio_size_ok(dev->bdev, first_bio, + bbio->stripes[dev_nr].physical >> 9)) { + ret = breakup_stripe_bio(root, bbio, first_bio, dev, + dev_nr, rw, async_submit); + BUG_ON(ret); + dev_nr++; + continue; + } + if (dev_nr < total_devs - 1) { bio = bio_clone(first_bio, GFP_NOFS); BUG_ON(!bio); /* -ENOMEM */ } else { bio = first_bio; } - bio->bi_private = bbio; - bio->bi_private = merge_stripe_index_into_bio_private( - bio->bi_private, (unsigned int)dev_nr); - bio->bi_end_io = btrfs_end_bio; - bio->bi_sector = bbio->stripes[dev_nr].physical >> 9; - dev = bbio->stripes[dev_nr].dev; - if (dev && dev->bdev && (rw != WRITE || dev->writeable)) { -#ifdef DEBUG - struct rcu_string *name; - - rcu_read_lock(); - name = rcu_dereference(dev->name); - pr_debug("btrfs_map_bio: rw %d, secor=%llu, dev=%lu " - "(%s id %llu), size=%u\n", rw, - (u64)bio->bi_sector, (u_long)dev->bdev->bd_dev, - name->str, dev->devid, bio->bi_size); - rcu_read_unlock(); -#endif - bio->bi_bdev = dev->bdev; - if (async_submit) - schedule_bio(root, dev, rw, bio); - else - btrfsic_submit_bio(rw, bio); - } else { - bio->bi_bdev = root->fs_info->fs_devices->latest_bdev; - bio->bi_sector = logical >> 9; - bio_endio(bio, -EIO); - } + + submit_stripe_bio(root, bbio, bio, + bbio->stripes[dev_nr].physical, dev_nr, rw, + async_submit); dev_nr++; } return 0; |