From 9eddacf9e9c03578ef2c07c9534423e823d677f8 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Tue, 10 Feb 2009 06:46:05 -0500 Subject: Revert "ext4: wait on all pending commits in ext4_sync_fs()" This undoes commit 14ce0cb411c88681ab8f3a4c9caa7f42e97a3184. Since jbd2_journal_start_commit() is now fixed to return 1 when we started a transaction commit, there's some transaction waiting to be committed or there's a transaction already committing, we don't need to call ext4_force_commit() in ext4_sync_fs(). Furthermore ext4_force_commit() can unnecessarily create sync transaction which is expensive so it's worthwhile to remove it when we can. http://bugzilla.kernel.org/show_bug.cgi?id=12224 Signed-off-by: Jan Kara Signed-off-by: "Theodore Ts'o" Cc: Eric Sandeen Cc: linux-ext4@vger.kernel.org --- fs/ext4/super.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) (limited to 'fs/ext4') diff --git a/fs/ext4/super.c b/fs/ext4/super.c index e5f06a5f045..a5732c58f67 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -3046,14 +3046,17 @@ static void ext4_write_super(struct super_block *sb) static int ext4_sync_fs(struct super_block *sb, int wait) { int ret = 0; + tid_t target; trace_mark(ext4_sync_fs, "dev %s wait %d", sb->s_id, wait); sb->s_dirt = 0; if (EXT4_SB(sb)->s_journal) { - if (wait) - ret = ext4_force_commit(sb); - else - jbd2_journal_start_commit(EXT4_SB(sb)->s_journal, NULL); + if (jbd2_journal_start_commit(EXT4_SB(sb)->s_journal, + &target)) { + if (wait) + jbd2_log_wait_commit(EXT4_SB(sb)->s_journal, + target); + } } else { ext4_commit_super(sb, EXT4_SB(sb)->s_es, wait); } -- cgit From 7f5aa215088b817add9c71914b83650bdd49f8a9 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Tue, 10 Feb 2009 11:15:34 -0500 Subject: jbd2: Avoid possible NULL dereference in jbd2_journal_begin_ordered_truncate() If we race with commit code setting i_transaction to NULL, we could possibly dereference it. Proper locking requires the journal pointer (to access journal->j_list_lock), which we don't have. So we have to change the prototype of the function so that filesystem passes us the journal pointer. Also add a more detailed comment about why the function jbd2_journal_begin_ordered_truncate() does what it does and how it should be used. Thanks to Dan Carpenter for pointing to the suspitious code. Signed-off-by: Jan Kara Signed-off-by: "Theodore Ts'o" Acked-by: Joel Becker CC: linux-ext4@vger.kernel.org CC: ocfs2-devel@oss.oracle.com CC: mfasheh@suse.de CC: Dan Carpenter --- fs/ext4/inode.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'fs/ext4') diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 03ba20be132..658c4a7f257 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -47,8 +47,10 @@ static inline int ext4_begin_ordered_truncate(struct inode *inode, loff_t new_size) { - return jbd2_journal_begin_ordered_truncate(&EXT4_I(inode)->jinode, - new_size); + return jbd2_journal_begin_ordered_truncate( + EXT4_SB(inode->i_sb)->s_journal, + &EXT4_I(inode)->jinode, + new_size); } static void ext4_invalidatepage(struct page *page, unsigned long offset); -- cgit From 7be2baaa0322c59ba888aa5260a8c130666acd41 Mon Sep 17 00:00:00 2001 From: Wei Yongjun Date: Tue, 10 Feb 2009 09:53:42 -0500 Subject: ext4: Fix to read empty directory blocks correctly in 64k The rec_len field in the directory entry is 16 bits, so there was a problem representing rec_len for filesystems with a 64k block size in the case where the directory entry takes the entire 64k block. Unfortunately, there were two schemes that were proposed; one where all zeros meant 65536 and one where all ones (65535) meant 65536. E2fsprogs used 0, whereas the kernel used 65535. Oops. Fortunately this case happens extremely rarely, with the most common case being the lost+found directory, created by mke2fs. So we will be liberal in what we accept, and accept both encodings, but we will continue to encode 65536 as 65535. This will require a change in e2fsprogs, but with fortunately ext4 filesystems normally have the dir_index feature enabled, which precludes having a completely empty directory block. Signed-off-by: Wei Yongjun Signed-off-by: "Theodore Ts'o" --- fs/ext4/ext4.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/ext4') diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index aafc9eba1c2..b0c87dce66a 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -868,7 +868,7 @@ static inline unsigned ext4_rec_len_from_disk(__le16 dlen) { unsigned len = le16_to_cpu(dlen); - if (len == EXT4_MAX_REC_LEN) + if (len == EXT4_MAX_REC_LEN || len == 0) return 1 << 16; return len; } -- cgit From ba4439165f0f0d25b2fe065cf0c1ff8130b802eb Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Tue, 10 Feb 2009 11:14:34 -0500 Subject: ext4: Fix lockdep warning We should not call ext4_mb_add_n_trim while holding alloc_semp. ============================================= [ INFO: possible recursive locking detected ] 2.6.29-rc4-git1-dirty #124 --------------------------------------------- ffsb/3116 is trying to acquire lock: (&meta_group_info[i]->alloc_sem){----}, at: [] ext4_mb_load_buddy+0xd2/0x343 but task is already holding lock: (&meta_group_info[i]->alloc_sem){----}, at: [] ext4_mb_load_buddy+0xd2/0x343 http://bugzilla.kernel.org/show_bug.cgi?id=12672 Signed-off-by: Aneesh Kumar K.V Signed-off-by: "Theodore Ts'o" --- fs/ext4/mballoc.c | 29 ++++++++++++++++------------- 1 file changed, 16 insertions(+), 13 deletions(-) (limited to 'fs/ext4') diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index deba54f6cbe..c962d069050 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -4476,23 +4476,26 @@ static int ext4_mb_release_context(struct ext4_allocation_context *ac) pa->pa_free -= ac->ac_b_ex.fe_len; pa->pa_len -= ac->ac_b_ex.fe_len; spin_unlock(&pa->pa_lock); - /* - * We want to add the pa to the right bucket. - * Remove it from the list and while adding - * make sure the list to which we are adding - * doesn't grow big. - */ - if (likely(pa->pa_free)) { - spin_lock(pa->pa_obj_lock); - list_del_rcu(&pa->pa_inode_list); - spin_unlock(pa->pa_obj_lock); - ext4_mb_add_n_trim(ac); - } } - ext4_mb_put_pa(ac, ac->ac_sb, pa); } if (ac->alloc_semp) up_read(ac->alloc_semp); + if (pa) { + /* + * We want to add the pa to the right bucket. + * Remove it from the list and while adding + * make sure the list to which we are adding + * doesn't grow big. We need to release + * alloc_semp before calling ext4_mb_add_n_trim() + */ + if (pa->pa_linear && likely(pa->pa_free)) { + spin_lock(pa->pa_obj_lock); + list_del_rcu(&pa->pa_inode_list); + spin_unlock(pa->pa_obj_lock); + ext4_mb_add_n_trim(ac); + } + ext4_mb_put_pa(ac, ac->ac_sb, pa); + } if (ac->ac_bitmap_page) page_cache_release(ac->ac_bitmap_page); if (ac->ac_buddy_page) -- cgit From d794bf8e0936dce45104565cd48c571061f4c1e3 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Sat, 14 Feb 2009 10:31:16 -0500 Subject: ext4: Initialize preallocation list_head's properly When creating a new ext4_prealloc_space structure, we have to initialize its list_head pointers before we add them to any prealloc lists. Otherwise, with list debug enabled, we will get list corruption warnings. Signed-off-by: Aneesh Kumar K.V Signed-off-by: "Theodore Ts'o" --- fs/ext4/mballoc.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'fs/ext4') diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index c962d069050..4415beeb0b6 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -3693,6 +3693,8 @@ ext4_mb_new_inode_pa(struct ext4_allocation_context *ac) pa->pa_free = pa->pa_len; atomic_set(&pa->pa_count, 1); spin_lock_init(&pa->pa_lock); + INIT_LIST_HEAD(&pa->pa_inode_list); + INIT_LIST_HEAD(&pa->pa_group_list); pa->pa_deleted = 0; pa->pa_linear = 0; @@ -3755,6 +3757,7 @@ ext4_mb_new_group_pa(struct ext4_allocation_context *ac) atomic_set(&pa->pa_count, 1); spin_lock_init(&pa->pa_lock); INIT_LIST_HEAD(&pa->pa_inode_list); + INIT_LIST_HEAD(&pa->pa_group_list); pa->pa_deleted = 0; pa->pa_linear = 1; -- cgit From 2acf2c261b823d9d9ed954f348b97620297a36b5 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Sat, 14 Feb 2009 10:42:58 -0500 Subject: ext4: Implement range_cyclic in ext4_da_writepages instead of write_cache_pages With delayed allocation we lock the page in write_cache_pages() and try to build an in memory extent of contiguous blocks. This is needed so that we can get large contiguous blocks request. If range_cyclic mode is enabled, write_cache_pages() will loop back to the 0 index if no I/O has been done yet, and try to start writing from the beginning of the range. That causes an attempt to take the page lock of lower index page while holding the page lock of higher index page, which can cause a dead lock with another writeback thread. The solution is to implement the range_cyclic behavior in ext4_da_writepages() instead. http://bugzilla.kernel.org/show_bug.cgi?id=12579 Signed-off-by: Aneesh Kumar K.V Signed-off-by: "Theodore Ts'o" --- fs/ext4/inode.c | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) (limited to 'fs/ext4') diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 658c4a7f257..cbd2ca99d11 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -2439,6 +2439,7 @@ static int ext4_da_writepages(struct address_space *mapping, int no_nrwrite_index_update; int pages_written = 0; long pages_skipped; + int range_cyclic, cycled = 1, io_done = 0; int needed_blocks, ret = 0, nr_to_writebump = 0; struct ext4_sb_info *sbi = EXT4_SB(mapping->host->i_sb); @@ -2490,9 +2491,15 @@ static int ext4_da_writepages(struct address_space *mapping, if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) range_whole = 1; - if (wbc->range_cyclic) + range_cyclic = wbc->range_cyclic; + if (wbc->range_cyclic) { index = mapping->writeback_index; - else + if (index) + cycled = 0; + wbc->range_start = index << PAGE_CACHE_SHIFT; + wbc->range_end = LLONG_MAX; + wbc->range_cyclic = 0; + } else index = wbc->range_start >> PAGE_CACHE_SHIFT; mpd.wbc = wbc; @@ -2506,6 +2513,7 @@ static int ext4_da_writepages(struct address_space *mapping, wbc->no_nrwrite_index_update = 1; pages_skipped = wbc->pages_skipped; +retry: while (!ret && wbc->nr_to_write > 0) { /* @@ -2548,6 +2556,7 @@ static int ext4_da_writepages(struct address_space *mapping, pages_written += mpd.pages_written; wbc->pages_skipped = pages_skipped; ret = 0; + io_done = 1; } else if (wbc->nr_to_write) /* * There is no more writeout needed @@ -2556,6 +2565,13 @@ static int ext4_da_writepages(struct address_space *mapping, */ break; } + if (!io_done && !cycled) { + cycled = 1; + index = 0; + wbc->range_start = index << PAGE_CACHE_SHIFT; + wbc->range_end = mapping->writeback_index - 1; + goto retry; + } if (pages_skipped != wbc->pages_skipped) printk(KERN_EMERG "This should not happen leaving %s " "with nr_to_write = %ld ret = %d\n", @@ -2563,6 +2579,7 @@ static int ext4_da_writepages(struct address_space *mapping, /* Update index */ index += pages_written; + wbc->range_cyclic = range_cyclic; if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0)) /* * set the writeback_index so that range_cyclic -- cgit From 090542641de833c6f756895fc2f139f046e298f9 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Sun, 15 Feb 2009 20:02:19 -0500 Subject: ext4: Fix NULL dereference in ext4_ext_migrate()'s error handling This was found through a code checker (http://repo.or.cz/w/smatch.git/). It looks like you might be able to trigger the error by trying to migrate a readonly file system. Signed-off-by: Dan Carpenter Signed-off-by: "Theodore Ts'o" --- fs/ext4/migrate.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) (limited to 'fs/ext4') diff --git a/fs/ext4/migrate.c b/fs/ext4/migrate.c index 734abca25e3..fe64d9f7985 100644 --- a/fs/ext4/migrate.c +++ b/fs/ext4/migrate.c @@ -481,7 +481,7 @@ int ext4_ext_migrate(struct inode *inode) + 1); if (IS_ERR(handle)) { retval = PTR_ERR(handle); - goto err_out; + return retval; } tmp_inode = ext4_new_inode(handle, inode->i_sb->s_root->d_inode, @@ -489,8 +489,7 @@ int ext4_ext_migrate(struct inode *inode) if (IS_ERR(tmp_inode)) { retval = -ENOMEM; ext4_journal_stop(handle); - tmp_inode = NULL; - goto err_out; + return retval; } i_size_write(tmp_inode, i_size_read(inode)); /* @@ -618,8 +617,7 @@ err_out: ext4_journal_stop(handle); - if (tmp_inode) - iput(tmp_inode); + iput(tmp_inode); return retval; } -- cgit