From 202ee5df38b33f7ea28286807a0b548b49613194 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Mon, 21 Apr 2014 14:37:55 -0400 Subject: [PATCH] ext4: add a new spinlock i_raw_lock to protect the ext4's raw inode To avoid potential data races, use a spinlock which protects the raw (on-disk) inode. Signed-off-by: "Theodore Ts'o" Reviewed-by: Jan Kara --- fs/ext4/ext4.h | 2 ++ fs/ext4/inode.c | 41 ++++++++++++++++++++++------------------- fs/ext4/super.c | 1 + 3 files changed, 25 insertions(+), 19 deletions(-) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 86c2cda208ea..1d08a1b51bdd 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -875,6 +875,8 @@ struct ext4_inode_info { struct inode vfs_inode; struct jbd2_inode *jinode; + spinlock_t i_raw_lock; /* protects updates to the raw inode */ + /* * File creation time. Its function is same as that of * struct timespec i_{a,c,m}time in the generic inode. diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 7dfbcbba67d5..9b3c52fbe86d 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -4305,12 +4305,15 @@ static int ext4_do_update_inode(handle_t *handle, struct ext4_inode *raw_inode = ext4_raw_inode(iloc); struct ext4_inode_info *ei = EXT4_I(inode); struct buffer_head *bh = iloc->bh; + struct super_block *sb = inode->i_sb; int err = 0, rc, block; - int need_datasync = 0; + int need_datasync = 0, set_large_file = 0; uid_t i_uid; gid_t i_gid; - /* For fields not not tracking in the in-memory inode, + spin_lock(&ei->i_raw_lock); + + /* For fields not tracked in the in-memory inode, * initialise them to zero for new inodes. */ if (ext4_test_inode_state(inode, EXT4_STATE_NEW)) memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size); @@ -4348,8 +4351,10 @@ static int ext4_do_update_inode(handle_t *handle, EXT4_INODE_SET_XTIME(i_atime, inode, raw_inode); EXT4_EINODE_SET_XTIME(i_crtime, ei, raw_inode); - if (ext4_inode_blocks_set(handle, raw_inode, ei)) + if (ext4_inode_blocks_set(handle, raw_inode, ei)) { + spin_unlock(&ei->i_raw_lock); goto out_brelse; + } raw_inode->i_dtime = cpu_to_le32(ei->i_dtime); raw_inode->i_flags = cpu_to_le32(ei->i_flags & 0xFFFFFFFF); if (likely(!test_opt2(inode->i_sb, HURD_COMPAT))) @@ -4361,24 +4366,11 @@ static int ext4_do_update_inode(handle_t *handle, need_datasync = 1; } if (ei->i_disksize > 0x7fffffffULL) { - struct super_block *sb = inode->i_sb; if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_LARGE_FILE) || EXT4_SB(sb)->s_es->s_rev_level == - cpu_to_le32(EXT4_GOOD_OLD_REV)) { - /* If this is the first large file - * created, add a flag to the superblock. - */ - err = ext4_journal_get_write_access(handle, - EXT4_SB(sb)->s_sbh); - if (err) - goto out_brelse; - ext4_update_dynamic_rev(sb); - EXT4_SET_RO_COMPAT_FEATURE(sb, - EXT4_FEATURE_RO_COMPAT_LARGE_FILE); - ext4_handle_sync(handle); - err = ext4_handle_dirty_super(handle, sb); - } + cpu_to_le32(EXT4_GOOD_OLD_REV)) + set_large_file = 1; } raw_inode->i_generation = cpu_to_le32(inode->i_generation); if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) { @@ -4410,12 +4402,23 @@ static int ext4_do_update_inode(handle_t *handle, ext4_inode_csum_set(inode, raw_inode, ei); + spin_unlock(&ei->i_raw_lock); + BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); rc = ext4_handle_dirty_metadata(handle, NULL, bh); if (!err) err = rc; ext4_clear_inode_state(inode, EXT4_STATE_NEW); - + if (set_large_file) { + err = ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh); + if (err) + goto out_brelse; + ext4_update_dynamic_rev(sb); + EXT4_SET_RO_COMPAT_FEATURE(sb, + EXT4_FEATURE_RO_COMPAT_LARGE_FILE); + ext4_handle_sync(handle); + err = ext4_handle_dirty_super(handle, sb); + } ext4_update_inode_fsync_trans(handle, inode, need_datasync); out_brelse: brelse(bh); diff --git a/fs/ext4/super.c b/fs/ext4/super.c index c4895c195e00..1f8cb1812723 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -879,6 +879,7 @@ static struct inode *ext4_alloc_inode(struct super_block *sb) return NULL; ei->vfs_inode.i_version = 1; + spin_lock_init(&ei->i_raw_lock); INIT_LIST_HEAD(&ei->i_prealloc_list); spin_lock_init(&ei->i_prealloc_lock); ext4_es_init_tree(&ei->i_es_tree); -- 2.34.1