diff options
| -rw-r--r-- | fs/btrfs/compression.c | 168 |
1 files changed, 97 insertions, 71 deletions
diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c index 13814737420c..f3cb18afec20 100644 --- a/fs/btrfs/compression.c +++ b/fs/btrfs/compression.c @@ -435,12 +435,31 @@ static blk_status_t submit_compressed_bio(struct btrfs_fs_info *fs_info, } /* - * Allocate a compressed_bio, which will be used to read/write on-disk data. + * Allocate a compressed_bio, which will be used to read/write on-disk + * (aka, compressed) * data. + * + * @cb: The compressed_bio structure, which records all the needed + * information to bind the compressed data to the uncompressed + * page cache. + * @disk_byten: The logical bytenr where the compressed data will be read + * from or written to. + * @endio_func: The endio function to call after the IO for compressed data + * is finished. + * @next_stripe_start: Return value of logical bytenr of where next stripe starts. + * Let the caller know to only fill the bio up to the stripe + * boundary. */ + + static struct bio *alloc_compressed_bio(struct compressed_bio *cb, u64 disk_bytenr, - unsigned int opf, bio_end_io_t endio_func) + unsigned int opf, bio_end_io_t endio_func, + u64 *next_stripe_start) { + struct btrfs_fs_info *fs_info = btrfs_sb(cb->inode->i_sb); + struct btrfs_io_geometry geom; + struct extent_map *em; struct bio *bio; + int ret; bio = btrfs_bio_alloc(BIO_MAX_VECS); @@ -449,18 +468,23 @@ static struct bio *alloc_compressed_bio(struct compressed_bio *cb, u64 disk_byte bio->bi_private = cb; bio->bi_end_io = endio_func; - if (bio_op(bio) == REQ_OP_ZONE_APPEND) { - struct btrfs_fs_info *fs_info = btrfs_sb(cb->inode->i_sb); - struct btrfs_device *device; + em = btrfs_get_chunk_map(fs_info, disk_bytenr, fs_info->sectorsize); + if (IS_ERR(em)) { + bio_put(bio); + return ERR_CAST(em); + } - device = btrfs_zoned_get_device(fs_info, disk_bytenr, - fs_info->sectorsize); - if (IS_ERR(device)) { - bio_put(bio); - return ERR_CAST(device); - } - bio_set_dev(bio, device->bdev); + if (bio_op(bio) == REQ_OP_ZONE_APPEND) + bio_set_dev(bio, em->map_lookup->stripes[0].dev->bdev); + + ret = btrfs_get_io_geometry(fs_info, em, btrfs_op(bio), disk_bytenr, &geom); + free_extent_map(em); + if (ret < 0) { + bio_put(bio); + return ERR_PTR(ret); } + *next_stripe_start = disk_bytenr + geom.len; + return bio; } @@ -488,6 +512,7 @@ blk_status_t btrfs_submit_compressed_write(struct btrfs_inode *inode, u64 start, int pg_index = 0; struct page *page; u64 first_byte = disk_start; + u64 next_stripe_start; blk_status_t ret; int skip_sum = inode->flags & BTRFS_INODE_NODATASUM; const bool use_append = btrfs_use_zone_append(inode, disk_start); @@ -510,7 +535,7 @@ blk_status_t btrfs_submit_compressed_write(struct btrfs_inode *inode, u64 start, cb->nr_pages = nr_pages; bio = alloc_compressed_bio(cb, first_byte, bio_op | write_flags, - end_compressed_bio_write); + end_compressed_bio_write, &next_stripe_start); if (IS_ERR(bio)) { kfree(cb); return errno_to_blk_status(PTR_ERR(bio)); @@ -559,7 +584,8 @@ blk_status_t btrfs_submit_compressed_write(struct btrfs_inode *inode, u64 start, bio = alloc_compressed_bio(cb, first_byte, bio_op | write_flags, - end_compressed_bio_write); + end_compressed_bio_write, + &next_stripe_start); if (IS_ERR(bio)) { ret = errno_to_blk_status(PTR_ERR(bio)); bio = NULL; @@ -790,9 +816,10 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, unsigned int compressed_len; unsigned int nr_pages; unsigned int pg_index; - struct page *page; - struct bio *comp_bio; - u64 cur_disk_byte = bio->bi_iter.bi_sector << 9; + struct bio *comp_bio = NULL; + const u64 disk_bytenr = bio->bi_iter.bi_sector << SECTOR_SHIFT; + u64 cur_disk_byte = disk_bytenr; + u64 next_stripe_start; u64 file_offset; u64 em_len; u64 em_start; @@ -860,39 +887,58 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, /* include any pages we added in add_ra-bio_pages */ cb->len = bio->bi_iter.bi_size; - comp_bio = alloc_compressed_bio(cb, cur_disk_byte, REQ_OP_READ, - end_compressed_bio_read); - if (IS_ERR(comp_bio)) { - ret = errno_to_blk_status(PTR_ERR(comp_bio)); - comp_bio = NULL; - goto fail2; - } + while (cur_disk_byte < disk_bytenr + compressed_len) { + u64 offset = cur_disk_byte - disk_bytenr; + unsigned int index = offset >> PAGE_SHIFT; + unsigned int real_size; + unsigned int added; + struct page *page = cb->compressed_pages[index]; + bool submit = false; - for (pg_index = 0; pg_index < nr_pages; pg_index++) { - u32 pg_len = PAGE_SIZE; - int submit = 0; + /* Allocate new bio if submitted or not yet allocated */ + if (!comp_bio) { + comp_bio = alloc_compressed_bio(cb, cur_disk_byte, + REQ_OP_READ, end_compressed_bio_read, + &next_stripe_start); + if (IS_ERR(comp_bio)) { + ret = errno_to_blk_status(PTR_ERR(comp_bio)); + comp_bio = NULL; + goto finish_cb; + } + } + /* + * We should never reach next_stripe_start start as we will + * submit comp_bio when reach the boundary immediately. + */ + ASSERT(cur_disk_byte != next_stripe_start); + /* + * We have various limit on the real read size: + * - stripe boundary + * - page boundary + * - compressed length boundary + */ + real_size = min_t(u64, U32_MAX, next_stripe_start - cur_disk_byte); + real_size = min_t(u64, real_size, PAGE_SIZE - offset_in_page(offset)); + real_size = min_t(u64, real_size, compressed_len - offset); + ASSERT(IS_ALIGNED(real_size, fs_info->sectorsize)); + added = bio_add_page(comp_bio, page, real_size, offset_in_page(offset)); /* - * To handle subpage case, we need to make sure the bio only - * covers the range we need. - * - * If we're at the last page, truncate the length to only cover - * the remaining part. + * Maximum compressed extent is smaller than bio size limit, + * thus bio_add_page() should always success. */ - if (pg_index == nr_pages - 1) - pg_len = min_t(u32, PAGE_SIZE, - compressed_len - pg_index * PAGE_SIZE); + ASSERT(added == real_size); + cur_disk_byte += added; - page = cb->compressed_pages[pg_index]; - page->mapping = inode->i_mapping; - page->index = em_start >> PAGE_SHIFT; + /* Reached stripe boundary, need to submit */ + if (cur_disk_byte == next_stripe_start) + submit = true; - if (comp_bio->bi_iter.bi_size) - submit = btrfs_bio_fits_in_stripe(page, pg_len, - comp_bio, 0); + /* Has finished the range, need to submit */ + if (cur_disk_byte == disk_bytenr + compressed_len) + submit = true; - page->mapping = NULL; - if (submit || bio_add_page(comp_bio, page, pg_len, 0) < pg_len) { + if (submit) { unsigned int nr_sectors; ret = btrfs_lookup_bio_sums(inode, comp_bio, sums); @@ -906,29 +952,9 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, ret = submit_compressed_bio(fs_info, cb, comp_bio, mirror_num); if (ret) goto finish_cb; - - comp_bio = alloc_compressed_bio(cb, cur_disk_byte, - REQ_OP_READ, - end_compressed_bio_read); - if (IS_ERR(comp_bio)) { - ret = errno_to_blk_status(PTR_ERR(comp_bio)); - comp_bio = NULL; - goto finish_cb; - } - - bio_add_page(comp_bio, page, pg_len, 0); + comp_bio = NULL; } - cur_disk_byte += pg_len; } - - ret = btrfs_lookup_bio_sums(inode, comp_bio, sums); - if (ret) - goto last_bio; - - ret = submit_compressed_bio(fs_info, cb, comp_bio, mirror_num); - if (ret) - goto last_bio; - return 0; fail2: @@ -943,18 +969,18 @@ fail1: out: free_extent_map(em); return ret; -last_bio: - comp_bio->bi_status = ret; - /* This is the last bio, endio functions will free @cb */ - bio_endio(comp_bio); - return ret; - finish_cb: if (comp_bio) { comp_bio->bi_status = ret; bio_endio(comp_bio); } - wait_var_event(cb, atomic_read(&cb->pending_bios) == 0); + /* All bytes of @cb is submitted, endio will free @cb */ + if (cur_disk_byte == disk_bytenr + compressed_len) + return ret; + + wait_var_event(cb, refcount_read(&cb->pending_sectors) == + (disk_bytenr + compressed_len - cur_disk_byte) >> + fs_info->sectorsize_bits); /* * Even with previous bio ended, we should still have io not yet * submitted, thus need to finish @cb manually. |