From ce9f24cccdc019229b70a5c15e2b09ad9c0ab5d1 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Tue, 28 Jul 2020 15:04:34 +0200 Subject: ext4: check journal inode extents more carefully Currently, system zones just track ranges of block, that are "important" fs metadata (bitmaps, group descriptors, journal blocks, etc.). This however complicates how extent tree (or indirect blocks) can be checked for inodes that actually track such metadata - currently the journal inode but arguably we should be treating quota files or resize inode similarly. We cannot run __ext4_ext_check() on such metadata inodes when loading their extents as that would immediately trigger the validity checks and so we just hack around that and special-case the journal inode. This however leads to a situation that a journal inode which has extent tree of depth at least one can have invalid extent tree that gets unnoticed until ext4_cache_extents() crashes. To overcome this limitation, track inode number each system zone belongs to (0 is used for zones not belonging to any inode). We can then verify inode number matches the expected one when verifying extent tree and thus avoid the false errors. With this there's no need to to special-case journal inode during extent tree checking anymore so remove it. Fixes: 0a944e8a6c66 ("ext4: don't perform block validity checks on the journal inode") Reported-by: Wolfgang Frisch Reviewed-by: Lukas Czerner Signed-off-by: Jan Kara Link: https://lore.kernel.org/r/20200728130437.7804-4-jack@suse.cz Signed-off-by: Theodore Ts'o --- fs/ext4/indirect.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) (limited to 'fs/ext4/indirect.c') diff --git a/fs/ext4/indirect.c b/fs/ext4/indirect.c index be2b66eb65f7..402641825712 100644 --- a/fs/ext4/indirect.c +++ b/fs/ext4/indirect.c @@ -858,8 +858,7 @@ static int ext4_clear_blocks(handle_t *handle, struct inode *inode, else if (ext4_should_journal_data(inode)) flags |= EXT4_FREE_BLOCKS_FORGET; - if (!ext4_data_block_valid(EXT4_SB(inode->i_sb), block_to_free, - count)) { + if (!ext4_inode_block_valid(inode, block_to_free, count)) { EXT4_ERROR_INODE(inode, "attempt to clear invalid " "blocks %llu len %lu", (unsigned long long) block_to_free, count); @@ -1004,8 +1003,7 @@ static void ext4_free_branches(handle_t *handle, struct inode *inode, if (!nr) continue; /* A hole */ - if (!ext4_data_block_valid(EXT4_SB(inode->i_sb), - nr, 1)) { + if (!ext4_inode_block_valid(inode, nr, 1)) { EXT4_ERROR_INODE(inode, "invalid indirect mapped " "block %lu (level %d)", -- cgit From 70d7ced2ed4dc3f7f21b4f4fec0e5be5c2a5a55c Mon Sep 17 00:00:00 2001 From: Shijie Luo Date: Mon, 10 Aug 2020 07:44:35 -0400 Subject: ext4: change to use fallthrough macro Change to use fallthrough macro in switch case. Signed-off-by: Shijie Luo Reviewed-by: Ritesh Harjani Link: https://lore.kernel.org/r/20200810114435.24182-1-luoshijie1@huawei.com Signed-off-by: Theodore Ts'o --- fs/ext4/indirect.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'fs/ext4/indirect.c') diff --git a/fs/ext4/indirect.c b/fs/ext4/indirect.c index 402641825712..433ca8415c5a 100644 --- a/fs/ext4/indirect.c +++ b/fs/ext4/indirect.c @@ -1180,21 +1180,21 @@ do_indirects: ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 1); i_data[EXT4_IND_BLOCK] = 0; } - /* fall through */ + fallthrough; case EXT4_IND_BLOCK: nr = i_data[EXT4_DIND_BLOCK]; if (nr) { ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 2); i_data[EXT4_DIND_BLOCK] = 0; } - /* fall through */ + fallthrough; case EXT4_DIND_BLOCK: nr = i_data[EXT4_TIND_BLOCK]; if (nr) { ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 3); i_data[EXT4_TIND_BLOCK] = 0; } - /* fall through */ + fallthrough; case EXT4_TIND_BLOCK: ; } @@ -1434,7 +1434,7 @@ do_indirects: ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 1); i_data[EXT4_IND_BLOCK] = 0; } - /* fall through */ + fallthrough; case EXT4_IND_BLOCK: if (++n >= n2) break; @@ -1443,7 +1443,7 @@ do_indirects: ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 2); i_data[EXT4_DIND_BLOCK] = 0; } - /* fall through */ + fallthrough; case EXT4_DIND_BLOCK: if (++n >= n2) break; @@ -1452,7 +1452,7 @@ do_indirects: ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 3); i_data[EXT4_TIND_BLOCK] = 0; } - /* fall through */ + fallthrough; case EXT4_TIND_BLOCK: ; } -- cgit From 27bc446e2def38db3244a6eb4bb1d6312936610a Mon Sep 17 00:00:00 2001 From: brookxu Date: Mon, 17 Aug 2020 15:36:15 +0800 Subject: ext4: limit the length of per-inode prealloc list MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In the scenario of writing sparse files, the per-inode prealloc list may be very long, resulting in high overhead for ext4_mb_use_preallocated(). To circumvent this problem, we limit the maximum length of per-inode prealloc list to 512 and allow users to modify it. After patching, we observed that the sys ratio of cpu has dropped, and the system throughput has increased significantly. We created a process to write the sparse file, and the running time of the process on the fixed kernel was significantly reduced, as follows: Running time on unfixed kernel： [root@TENCENT64 ~]# time taskset 0x01 ./sparse /data1/sparce.dat real 0m2.051s user 0m0.008s sys 0m2.026s Running time on fixed kernel： [root@TENCENT64 ~]# time taskset 0x01 ./sparse /data1/sparce.dat real 0m0.471s user 0m0.004s sys 0m0.395s Signed-off-by: Chunguang Xu Link: https://lore.kernel.org/r/d7a98178-056b-6db5-6bce-4ead23f4a257@gmail.com Signed-off-by: Theodore Ts'o --- fs/ext4/indirect.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/ext4/indirect.c') diff --git a/fs/ext4/indirect.c b/fs/ext4/indirect.c index 433ca8415c5a..80c9f33800be 100644 --- a/fs/ext4/indirect.c +++ b/fs/ext4/indirect.c @@ -696,7 +696,7 @@ static int ext4_ind_trunc_restart_fn(handle_t *handle, struct inode *inode, * i_mutex. So we can safely drop the i_data_sem here. */ BUG_ON(EXT4_JOURNAL(inode) == NULL); - ext4_discard_preallocations(inode); + ext4_discard_preallocations(inode, 0); up_write(&EXT4_I(inode)->i_data_sem); *dropped = 1; return 0; -- cgit