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| author | Jan Kara <jack@suse.cz> | 2013-06-04 13:21:11 -0400 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2013-06-04 13:21:11 -0400 |
| commit | 6b523df4fb5ae281ddbc817f40504b33e6226554 (patch) | |
| tree | f129ccf336689296ff21e34ed86712b25d437a65 /fs/ext4/ext4.h | |
| parent | 3613d22807a2616e9346800bacd88aa8bbbefcd7 (diff) | |
| download | op-kernel-dev-6b523df4fb5ae281ddbc817f40504b33e6226554.zip op-kernel-dev-6b523df4fb5ae281ddbc817f40504b33e6226554.tar.gz | |
ext4: use transaction reservation for extent conversion in ext4_end_io
Later we would like to clear PageWriteback bit only after extent
conversion from unwritten to written extents is performed. However it
is not possible to start a transaction after PageWriteback is set
because that violates lock ordering (and is easy to deadlock). So we
have to reserve a transaction before locking pages and sending them
for IO and later we use the transaction for extent conversion from
ext4_end_io().
Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Diffstat (limited to 'fs/ext4/ext4.h')
| -rw-r--r-- | fs/ext4/ext4.h | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 0a9b729..8de219b 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -184,10 +184,13 @@ struct ext4_map_blocks { #define EXT4_IO_END_DIRECT 0x0004 /* - * For converting uninitialized extents on a work queue. + * For converting uninitialized extents on a work queue. 'handle' is used for + * buffered writeback. */ typedef struct ext4_io_end { struct list_head list; /* per-file finished IO list */ + handle_t *handle; /* handle reserved for extent + * conversion */ struct inode *inode; /* file being written to */ unsigned int flag; /* unwritten or not */ loff_t offset; /* offset in the file */ @@ -1322,6 +1325,9 @@ static inline void ext4_set_io_unwritten_flag(struct inode *inode, struct ext4_io_end *io_end) { if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) { + /* Writeback has to have coversion transaction reserved */ + WARN_ON(EXT4_SB(inode->i_sb)->s_journal && !io_end->handle && + !(io_end->flag & EXT4_IO_END_DIRECT)); io_end->flag |= EXT4_IO_END_UNWRITTEN; atomic_inc(&EXT4_I(inode)->i_unwritten); } @@ -2591,8 +2597,8 @@ extern void ext4_ext_init(struct super_block *); extern void ext4_ext_release(struct super_block *); extern long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len); -extern int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset, - ssize_t len); +extern int ext4_convert_unwritten_extents(handle_t *handle, struct inode *inode, + loff_t offset, ssize_t len); extern int ext4_map_blocks(handle_t *handle, struct inode *inode, struct ext4_map_blocks *map, int flags); extern int ext4_ext_calc_metadata_amount(struct inode *inode, |
