diff options
author | Jan Kara <jack@suse.cz> | 2005-09-06 18:19:10 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@g5.osdl.org> | 2005-09-07 19:57:55 -0400 |
commit | a7662236253374012d364106b6dc9161bd929e2e (patch) | |
tree | 59f34811d18fef8195bc3200bdb2684598175f29 /fs/buffer.c | |
parent | e6c9f5c1888097c936334bf9740024520ca47b8e (diff) |
[PATCH] Make ll_rw_block() wait for buffer lock
Introduce new ll_rw_block() operation SWRITE meaning that block layer should
wait for the buffer lock and write-out afterwards. Hence data in buffers at
the time of call are guaranteed to be submitted to the disk.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'fs/buffer.c')
-rw-r--r-- | fs/buffer.c | 30 |
1 files changed, 16 insertions, 14 deletions
diff --git a/fs/buffer.c b/fs/buffer.c index a92b81403552..1c62203a4906 100644 --- a/fs/buffer.c +++ b/fs/buffer.c | |||
@@ -917,8 +917,7 @@ static int fsync_buffers_list(spinlock_t *lock, struct list_head *list) | |||
917 | * contents - it is a noop if I/O is still in | 917 | * contents - it is a noop if I/O is still in |
918 | * flight on potentially older contents. | 918 | * flight on potentially older contents. |
919 | */ | 919 | */ |
920 | wait_on_buffer(bh); | 920 | ll_rw_block(SWRITE, 1, &bh); |
921 | ll_rw_block(WRITE, 1, &bh); | ||
922 | brelse(bh); | 921 | brelse(bh); |
923 | spin_lock(lock); | 922 | spin_lock(lock); |
924 | } | 923 | } |
@@ -2793,21 +2792,22 @@ int submit_bh(int rw, struct buffer_head * bh) | |||
2793 | 2792 | ||
2794 | /** | 2793 | /** |
2795 | * ll_rw_block: low-level access to block devices (DEPRECATED) | 2794 | * ll_rw_block: low-level access to block devices (DEPRECATED) |
2796 | * @rw: whether to %READ or %WRITE or maybe %READA (readahead) | 2795 | * @rw: whether to %READ or %WRITE or %SWRITE or maybe %READA (readahead) |
2797 | * @nr: number of &struct buffer_heads in the array | 2796 | * @nr: number of &struct buffer_heads in the array |
2798 | * @bhs: array of pointers to &struct buffer_head | 2797 | * @bhs: array of pointers to &struct buffer_head |
2799 | * | 2798 | * |
2800 | * ll_rw_block() takes an array of pointers to &struct buffer_heads, | 2799 | * ll_rw_block() takes an array of pointers to &struct buffer_heads, and |
2801 | * and requests an I/O operation on them, either a %READ or a %WRITE. | 2800 | * requests an I/O operation on them, either a %READ or a %WRITE. The third |
2802 | * The third %READA option is described in the documentation for | 2801 | * %SWRITE is like %WRITE only we make sure that the *current* data in buffers |
2803 | * generic_make_request() which ll_rw_block() calls. | 2802 | * are sent to disk. The fourth %READA option is described in the documentation |
2803 | * for generic_make_request() which ll_rw_block() calls. | ||
2804 | * | 2804 | * |
2805 | * This function drops any buffer that it cannot get a lock on (with the | 2805 | * This function drops any buffer that it cannot get a lock on (with the |
2806 | * BH_Lock state bit), any buffer that appears to be clean when doing a | 2806 | * BH_Lock state bit) unless SWRITE is required, any buffer that appears to be |
2807 | * write request, and any buffer that appears to be up-to-date when doing | 2807 | * clean when doing a write request, and any buffer that appears to be |
2808 | * read request. Further it marks as clean buffers that are processed for | 2808 | * up-to-date when doing read request. Further it marks as clean buffers that |
2809 | * writing (the buffer cache won't assume that they are actually clean until | 2809 | * are processed for writing (the buffer cache won't assume that they are |
2810 | * the buffer gets unlocked). | 2810 | * actually clean until the buffer gets unlocked). |
2811 | * | 2811 | * |
2812 | * ll_rw_block sets b_end_io to simple completion handler that marks | 2812 | * ll_rw_block sets b_end_io to simple completion handler that marks |
2813 | * the buffer up-to-date (if approriate), unlocks the buffer and wakes | 2813 | * the buffer up-to-date (if approriate), unlocks the buffer and wakes |
@@ -2823,11 +2823,13 @@ void ll_rw_block(int rw, int nr, struct buffer_head *bhs[]) | |||
2823 | for (i = 0; i < nr; i++) { | 2823 | for (i = 0; i < nr; i++) { |
2824 | struct buffer_head *bh = bhs[i]; | 2824 | struct buffer_head *bh = bhs[i]; |
2825 | 2825 | ||
2826 | if (test_set_buffer_locked(bh)) | 2826 | if (rw == SWRITE) |
2827 | lock_buffer(bh); | ||
2828 | else if (test_set_buffer_locked(bh)) | ||
2827 | continue; | 2829 | continue; |
2828 | 2830 | ||
2829 | get_bh(bh); | 2831 | get_bh(bh); |
2830 | if (rw == WRITE) { | 2832 | if (rw == WRITE || rw == SWRITE) { |
2831 | if (test_clear_buffer_dirty(bh)) { | 2833 | if (test_clear_buffer_dirty(bh)) { |
2832 | bh->b_end_io = end_buffer_write_sync; | 2834 | bh->b_end_io = end_buffer_write_sync; |
2833 | submit_bh(WRITE, bh); | 2835 | submit_bh(WRITE, bh); |