From 01af106a076352182b2916b143fc50272600bd81 Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Tue, 21 Jan 2025 05:40:51 +0000 Subject: [PATCH] btrfs: fix two misuses of folio_shift() It is meaningless to shift a byte count by folio_shift(). The folio index is in units of PAGE_SIZE, not folio_size(). We can use folio_contains() to make this work for arbitrary-order folios, so remove the assertion that the folios are of order 0. Reviewed-by: Qu Wenruo Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/extent_io.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index d9f856358704..6f64ee16744d 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -523,8 +523,6 @@ static void end_bbio_data_read(struct btrfs_bio *bbio) u64 end; u32 len; - /* For now only order 0 folios are supported for data. */ - ASSERT(folio_order(folio) == 0); btrfs_debug(fs_info, "%s: bi_sector=%llu, err=%d, mirror=%u", __func__, bio->bi_iter.bi_sector, bio->bi_status, @@ -552,7 +550,6 @@ static void end_bbio_data_read(struct btrfs_bio *bbio) if (likely(uptodate)) { loff_t i_size = i_size_read(inode); - pgoff_t end_index = i_size >> folio_shift(folio); /* * Zero out the remaining part if this range straddles @@ -561,9 +558,11 @@ static void end_bbio_data_read(struct btrfs_bio *bbio) * Here we should only zero the range inside the folio, * not touch anything else. * - * NOTE: i_size is exclusive while end is inclusive. + * NOTE: i_size is exclusive while end is inclusive and + * folio_contains() takes PAGE_SIZE units. */ - if (folio_index(folio) == end_index && i_size <= end) { + if (folio_contains(folio, i_size >> PAGE_SHIFT) && + i_size <= end) { u32 zero_start = max(offset_in_folio(folio, i_size), offset_in_folio(folio, start)); u32 zero_len = offset_in_folio(folio, end) + 1 - @@ -956,7 +955,7 @@ static int btrfs_do_readpage(struct folio *folio, struct extent_map **em_cached, return ret; } - if (folio->index == last_byte >> folio_shift(folio)) { + if (folio_contains(folio, last_byte >> PAGE_SHIFT)) { size_t zero_offset = offset_in_folio(folio, last_byte); if (zero_offset) { -- 2.25.1