From 147d4a092e9a726ce706dbf0d329d2b96a025459 Mon Sep 17 00:00:00 2001 From: "Ritesh Harjani (IBM)" Date: Thu, 7 Sep 2023 09:47:32 -0400 Subject: jbd2: Remove page size assumptions jbd2_alloc() allocates a buffer from slab when the block size is smaller than PAGE_SIZE, and slab may be using a compound page. Before commit 8147c4c4546f, we set b_page to the precise page containing the buffer and this code worked well. Now we set b_page to the head page of the allocation, so we can no longer use offset_in_page(). While we could do a 1:1 replacement with offset_in_folio(), use the more idiomatic bh_offset() and the folio APIs to map the buffer. This isn't enough to support a b_size larger than PAGE_SIZE on HIGHMEM machines, but this is good enough to fix the actual bug we're seeing. Fixes: 8147c4c4546f ("jbd2: use a folio in jbd2_journal_write_metadata_buffer()") Reported-by: Zorro Lang Signed-off-by: Ritesh Harjani (IBM) [converted to be more folio] Signed-off-by: Matthew Wilcox (Oracle) --- fs/jbd2/commit.c | 16 ++++++---------- fs/jbd2/transaction.c | 12 ++++-------- 2 files changed, 10 insertions(+), 18 deletions(-) (limited to 'fs/jbd2') diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c index 1073259902a6..8d6f934c3d95 100644 --- a/fs/jbd2/commit.c +++ b/fs/jbd2/commit.c @@ -298,14 +298,12 @@ static int journal_finish_inode_data_buffers(journal_t *journal, static __u32 jbd2_checksum_data(__u32 crc32_sum, struct buffer_head *bh) { - struct page *page = bh->b_page; char *addr; __u32 checksum; - addr = kmap_atomic(page); - checksum = crc32_be(crc32_sum, - (void *)(addr + offset_in_page(bh->b_data)), bh->b_size); - kunmap_atomic(addr); + addr = kmap_local_folio(bh->b_folio, bh_offset(bh)); + checksum = crc32_be(crc32_sum, addr, bh->b_size); + kunmap_local(addr); return checksum; } @@ -322,7 +320,6 @@ static void jbd2_block_tag_csum_set(journal_t *j, journal_block_tag_t *tag, struct buffer_head *bh, __u32 sequence) { journal_block_tag3_t *tag3 = (journal_block_tag3_t *)tag; - struct page *page = bh->b_page; __u8 *addr; __u32 csum32; __be32 seq; @@ -331,11 +328,10 @@ static void jbd2_block_tag_csum_set(journal_t *j, journal_block_tag_t *tag, return; seq = cpu_to_be32(sequence); - addr = kmap_atomic(page); + addr = kmap_local_folio(bh->b_folio, bh_offset(bh)); csum32 = jbd2_chksum(j, j->j_csum_seed, (__u8 *)&seq, sizeof(seq)); - csum32 = jbd2_chksum(j, csum32, addr + offset_in_page(bh->b_data), - bh->b_size); - kunmap_atomic(addr); + csum32 = jbd2_chksum(j, csum32, addr, bh->b_size); + kunmap_local(addr); if (jbd2_has_feature_csum3(j)) tag3->t_checksum = cpu_to_be32(csum32); diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c index 4d1fda1f7143..5f08b5fd105a 100644 --- a/fs/jbd2/transaction.c +++ b/fs/jbd2/transaction.c @@ -935,19 +935,15 @@ static void warn_dirty_buffer(struct buffer_head *bh) /* Call t_frozen trigger and copy buffer data into jh->b_frozen_data. */ static void jbd2_freeze_jh_data(struct journal_head *jh) { - struct page *page; - int offset; char *source; struct buffer_head *bh = jh2bh(jh); J_EXPECT_JH(jh, buffer_uptodate(bh), "Possible IO failure.\n"); - page = bh->b_page; - offset = offset_in_page(bh->b_data); - source = kmap_atomic(page); + source = kmap_local_folio(bh->b_folio, bh_offset(bh)); /* Fire data frozen trigger just before we copy the data */ - jbd2_buffer_frozen_trigger(jh, source + offset, jh->b_triggers); - memcpy(jh->b_frozen_data, source + offset, bh->b_size); - kunmap_atomic(source); + jbd2_buffer_frozen_trigger(jh, source, jh->b_triggers); + memcpy(jh->b_frozen_data, source, bh->b_size); + kunmap_local(source); /* * Now that the frozen data is saved off, we need to store any matching -- cgit v1.2.3