From 63f32b7b5d5a9107d04fb11cc85d5cd695f85e19 Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Mon, 28 Apr 2025 10:06:50 +0930 Subject: btrfs: merge btrfs_read_dev_one_super() into btrfs_read_disk_super() We have two functions to read a super block from a block device: - btrfs_read_dev_one_super() Exported from disk-io.c - btrfs_read_disk_super() Local to volumes.c And they have some minor differences: - btrfs_read_dev_one_super() uses @copy_num Meanwhile btrfs_read_disk_super() relies on the physical and expected bytenr passed from the caller. The parameter list of btrfs_read_dev_one_super() is more user friendly. - btrfs_read_disk_super() makes sure the label is NUL terminated We do not need two different functions doing the same job, so merge the behavior into btrfs_read_disk_super() by: - Remove btrfs_read_dev_one_super() - Export btrfs_read_disk_super() The name pairs with btrfs_release_disk_super() perfectly. - Change the parameter list of btrfs_read_disk_super() to mimic btrfs_read_dev_one_super() All existing callers are calculating the physical address and expect bytenr before calling btrfs_read_disk_super() already. Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/disk-io.c | 53 +---------------------------------------------------- 1 file changed, 1 insertion(+), 52 deletions(-) (limited to 'fs/btrfs/disk-io.c') diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 1288b9bac47c..1768618d8a60 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -3712,57 +3712,6 @@ static void btrfs_end_super_write(struct bio *bio) bio_put(bio); } -struct btrfs_super_block *btrfs_read_dev_one_super(struct block_device *bdev, - int copy_num, bool drop_cache) -{ - struct btrfs_super_block *super; - struct page *page; - u64 bytenr, bytenr_orig; - struct address_space *mapping = bdev->bd_mapping; - int ret; - - bytenr_orig = btrfs_sb_offset(copy_num); - ret = btrfs_sb_log_location_bdev(bdev, copy_num, READ, &bytenr); - if (ret == -ENOENT) - return ERR_PTR(-EINVAL); - else if (ret) - return ERR_PTR(ret); - - if (bytenr + BTRFS_SUPER_INFO_SIZE >= bdev_nr_bytes(bdev)) - return ERR_PTR(-EINVAL); - - if (drop_cache) { - /* This should only be called with the primary sb. */ - ASSERT(copy_num == 0); - - /* - * Drop the page of the primary superblock, so later read will - * always read from the device. - */ - invalidate_inode_pages2_range(mapping, - bytenr >> PAGE_SHIFT, - (bytenr + BTRFS_SUPER_INFO_SIZE) >> PAGE_SHIFT); - } - - page = read_cache_page_gfp(mapping, bytenr >> PAGE_SHIFT, GFP_NOFS); - if (IS_ERR(page)) - return ERR_CAST(page); - - super = page_address(page); - if (btrfs_super_magic(super) != BTRFS_MAGIC) { - btrfs_release_disk_super(super); - return ERR_PTR(-ENODATA); - } - - if (btrfs_super_bytenr(super) != bytenr_orig) { - btrfs_release_disk_super(super); - return ERR_PTR(-EINVAL); - } - - return super; -} - - struct btrfs_super_block *btrfs_read_dev_super(struct block_device *bdev) { struct btrfs_super_block *super, *latest = NULL; @@ -3775,7 +3724,7 @@ struct btrfs_super_block *btrfs_read_dev_super(struct block_device *bdev) * later supers, using BTRFS_SUPER_MIRROR_MAX instead */ for (i = 0; i < 1; i++) { - super = btrfs_read_dev_one_super(bdev, i, false); + super = btrfs_read_disk_super(bdev, i, false); if (IS_ERR(super)) continue; -- cgit v1.2.3