From 6cd7ce4935485c203e0bda815dbabb50e30f31e9 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 25 Nov 2016 09:07:49 +0100 Subject: [PATCH] btrfs: don't access the bio directly in btrfs_csum_one_bio Use bio_for_each_segment_all to iterate over the segments instead. This requires a bit of reshuffling so that we only lookup up the ordered item once inside the bio_for_each_segment_all loop. Signed-off-by: Christoph Hellwig Reviewed-by: Omar Sandoval Signed-off-by: David Sterba --- fs/btrfs/file-item.c | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-) diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c index 43418c08b110..fad3804fc335 100644 --- a/fs/btrfs/file-item.c +++ b/fs/btrfs/file-item.c @@ -447,13 +447,12 @@ int btrfs_csum_one_bio(struct btrfs_root *root, struct inode *inode, struct bio *bio, u64 file_start, int contig) { struct btrfs_ordered_sum *sums; - struct btrfs_ordered_extent *ordered; + struct btrfs_ordered_extent *ordered = NULL; char *data; - struct bio_vec *bvec = bio->bi_io_vec; - int bio_index = 0; + struct bio_vec *bvec; int index; int nr_sectors; - int i; + int i, j; unsigned long total_bytes = 0; unsigned long this_sum_bytes = 0; u64 offset; @@ -470,17 +469,20 @@ int btrfs_csum_one_bio(struct btrfs_root *root, struct inode *inode, if (contig) offset = file_start; else - offset = page_offset(bvec->bv_page) + bvec->bv_offset; + offset = 0; /* shut up gcc */ - ordered = btrfs_lookup_ordered_extent(inode, offset); - BUG_ON(!ordered); /* Logic error */ sums->bytenr = (u64)bio->bi_iter.bi_sector << 9; index = 0; - while (bio_index < bio->bi_vcnt) { + bio_for_each_segment_all(bvec, bio, j) { if (!contig) offset = page_offset(bvec->bv_page) + bvec->bv_offset; + if (!ordered) { + ordered = btrfs_lookup_ordered_extent(inode, offset); + BUG_ON(!ordered); /* Logic error */ + } + data = kmap_atomic(bvec->bv_page); nr_sectors = BTRFS_BYTES_TO_BLKS(root->fs_info, @@ -529,9 +531,6 @@ int btrfs_csum_one_bio(struct btrfs_root *root, struct inode *inode, } kunmap_atomic(data); - - bio_index++; - bvec++; } this_sum_bytes = 0; btrfs_add_ordered_sum(inode, ordered, sums); -- 2.45.2