From 1a41802701ec78ca3272073e60463c13b17d121f Mon Sep 17 00:00:00 2001 From: David Sterba Date: Fri, 30 Aug 2019 19:39:19 +0200 Subject: btrfs: drop bio_set_dev where not needed bio_set_dev sets a bdev to a bio and is not only setting a pointer bug also changing some state bits if there was a different bdev set before. This is one thing that's not needed. Another thing is that setting a bdev at bio allocation time is too early and actually does not work with plain redundancy profiles, where each time we submit a bio to a device, the bdev is set correctly. In many places the bio bdev is set to latest_bdev that seems to serve as a stub pointer "just to put something to bio". But we don't have to do that. Where do we know which bdev to set: * for regular IO: submit_stripe_bio that's called by btrfs_map_bio * repair IO: repair_io_failure, read or write from specific device * super block write (using buffer_heads but uses raw bdev) and barriers * scrub: this does not use all regular IO paths as it needs to reach all copies, verify and fixup eventually, and for that all bdev management is independent * raid56: rbio_add_io_page, for the RMW write * integrity-checker: does it's own low-level block tracking Signed-off-by: David Sterba --- fs/btrfs/compression.c | 10 ---------- 1 file changed, 10 deletions(-) (limited to 'fs/btrfs/compression.c') diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c index 53aee0db9d71..ee834ef7beb4 100644 --- a/fs/btrfs/compression.c +++ b/fs/btrfs/compression.c @@ -422,7 +422,6 @@ blk_status_t btrfs_submit_compressed_write(struct inode *inode, u64 start, int pg_index = 0; struct page *page; u64 first_byte = disk_start; - struct block_device *bdev; blk_status_t ret; int skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM; @@ -441,10 +440,7 @@ blk_status_t btrfs_submit_compressed_write(struct inode *inode, u64 start, cb->orig_bio = NULL; cb->nr_pages = nr_pages; - bdev = fs_info->fs_devices->latest_bdev; - bio = btrfs_bio_alloc(first_byte); - bio_set_dev(bio, bdev); bio->bi_opf = REQ_OP_WRITE | write_flags; bio->bi_private = cb; bio->bi_end_io = end_compressed_bio_write; @@ -492,7 +488,6 @@ blk_status_t btrfs_submit_compressed_write(struct inode *inode, u64 start, } bio = btrfs_bio_alloc(first_byte); - bio_set_dev(bio, bdev); bio->bi_opf = REQ_OP_WRITE | write_flags; bio->bi_private = cb; bio->bi_end_io = end_compressed_bio_write; @@ -660,7 +655,6 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, unsigned long nr_pages; unsigned long pg_index; struct page *page; - struct block_device *bdev; struct bio *comp_bio; u64 cur_disk_byte = (u64)bio->bi_iter.bi_sector << 9; u64 em_len; @@ -711,8 +705,6 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, if (!cb->compressed_pages) goto fail1; - bdev = fs_info->fs_devices->latest_bdev; - for (pg_index = 0; pg_index < nr_pages; pg_index++) { cb->compressed_pages[pg_index] = alloc_page(GFP_NOFS | __GFP_HIGHMEM); @@ -731,7 +723,6 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, cb->len = bio->bi_iter.bi_size; comp_bio = btrfs_bio_alloc(cur_disk_byte); - bio_set_dev(comp_bio, bdev); comp_bio->bi_opf = REQ_OP_READ; comp_bio->bi_private = cb; comp_bio->bi_end_io = end_compressed_bio_read; @@ -782,7 +773,6 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, } comp_bio = btrfs_bio_alloc(cur_disk_byte); - bio_set_dev(comp_bio, bdev); comp_bio->bi_opf = REQ_OP_READ; comp_bio->bi_private = cb; comp_bio->bi_end_io = end_compressed_bio_read; -- cgit