From cf7ded644ed72747748b62dd7eda7e67c2d1b547 Mon Sep 17 00:00:00 2001 From: Tal Zussman Date: Mon, 7 Sep 2026 16:20:01 -0400 Subject: [PATCH] btrfs: use folios for reading super blocks from the block device btrfs_read_disk_super() and the zoned super block log comparison go through read_cache_page_gfp() and page_address(), and btrfs_release_disk_super() recovers the page with virt_to_page(). Use mapping_read_folio_gfp(), folio_address(), and virt_to_folio() instead. This removes the last callers of read_cache_page_gfp() and put_page() in btrfs. Compute the super block address with offset_in_folio() as write_dev_supers() does, rather than assuming it is at the start of the page. Assisted-by: Claude:claude-fable-5-1 Reviewed-by: Qu Wenruo Signed-off-by: Tal Zussman Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/volumes.c | 16 +++++++--------- fs/btrfs/zoned.c | 12 ++++++------ 2 files changed, 13 insertions(+), 15 deletions(-) diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 1fad1aa716de..7c040f22dbc3 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -1358,16 +1358,14 @@ int btrfs_open_devices(struct btrfs_fs_devices *fs_devices, void btrfs_release_disk_super(struct btrfs_super_block *super) { - struct page *page = virt_to_page(super); - - put_page(page); + folio_put(virt_to_folio(super)); } struct btrfs_super_block *btrfs_read_disk_super(struct block_device *bdev, int copy_num, bool drop_cache) { struct btrfs_super_block *super; - struct page *page; + struct folio *folio; u64 bytenr, bytenr_orig; struct address_space *mapping = bdev->bd_mapping; int ret; @@ -1388,7 +1386,7 @@ struct btrfs_super_block *btrfs_read_disk_super(struct block_device *bdev, ASSERT(copy_num == 0); /* - * Drop the page of the primary superblock, so later read will + * Drop the folio of the primary superblock, so later read will * always read from the device. */ invalidate_inode_pages2_range(mapping, bytenr >> PAGE_SHIFT, @@ -1396,12 +1394,12 @@ struct btrfs_super_block *btrfs_read_disk_super(struct block_device *bdev, } filemap_invalidate_lock_shared(mapping); - page = read_cache_page_gfp(mapping, bytenr >> PAGE_SHIFT, GFP_NOFS); + folio = mapping_read_folio_gfp(mapping, bytenr >> PAGE_SHIFT, GFP_NOFS); filemap_invalidate_unlock_shared(mapping); - if (IS_ERR(page)) - return ERR_CAST(page); + if (IS_ERR(folio)) + return ERR_CAST(folio); - super = page_address(page); + super = folio_address(folio) + offset_in_folio(folio, bytenr); if (btrfs_super_magic(super) != BTRFS_MAGIC || btrfs_super_bytenr(super) != bytenr_orig) { btrfs_release_disk_super(super); diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c index 08a15465a087..a1ef8caaacda 100644 --- a/fs/btrfs/zoned.c +++ b/fs/btrfs/zoned.c @@ -123,24 +123,24 @@ static int sb_write_pointer(struct block_device *bdev, struct blk_zone *zones, } else if (full[0] && full[1]) { /* Compare two super blocks */ struct address_space *mapping = bdev->bd_mapping; - struct page *page[BTRFS_NR_SB_LOG_ZONES]; struct btrfs_super_block *super[BTRFS_NR_SB_LOG_ZONES]; for (int i = 0; i < BTRFS_NR_SB_LOG_ZONES; i++) { u64 zone_end = (zones[i].start + zones[i].capacity) << SECTOR_SHIFT; u64 bytenr = ALIGN_DOWN(zone_end, BTRFS_SUPER_INFO_SIZE) - BTRFS_SUPER_INFO_SIZE; + struct folio *folio; filemap_invalidate_lock_shared(mapping); - page[i] = read_cache_page_gfp(mapping, - bytenr >> PAGE_SHIFT, GFP_NOFS); + folio = mapping_read_folio_gfp(mapping, bytenr >> PAGE_SHIFT, + GFP_NOFS); filemap_invalidate_unlock_shared(mapping); - if (IS_ERR(page[i])) { + if (IS_ERR(folio)) { if (i == 1) btrfs_release_disk_super(super[0]); - return PTR_ERR(page[i]); + return PTR_ERR(folio); } - super[i] = page_address(page[i]); + super[i] = folio_address(folio) + offset_in_folio(folio, bytenr); } if (btrfs_super_generation(super[0]) >