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| author | Yongqiang Yang <xiaoqiangnk@gmail.com> | 2011-12-28 23:46:46 +0100 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2011-12-28 23:46:46 +0100 |
| commit | 1ba37268cd19e5a2a80924bfe8618bf1ba3e8249 (patch) | |
| tree | f4227aaf3963e6c948b01e57c98697e6ab2157d6 /fs/jbd2/revoke.c | |
| parent | ext4: flush journal when switching from data=journal mode (diff) | |
| download | linux-1ba37268cd19e5a2a80924bfe8618bf1ba3e8249.tar.xz linux-1ba37268cd19e5a2a80924bfe8618bf1ba3e8249.zip | |
jbd2: clear revoked flag on buffers before a new transaction started
Currently, we clear revoked flag only when a block is reused. However,
this can tigger a false journal error. Consider a situation when a block
is used as a meta block and is deleted(revoked) in ordered mode, then the
block is allocated as a data block to a file. At this moment, user changes
the file's journal mode from ordered to journaled and truncates the file.
The block will be considered re-revoked by journal because it has revoked
flag still pending from the last transaction and an assertion triggers.
We fix the problem by keeping the revoked status more uptodate - we clear
revoked flag when switching revoke tables to reflect there is no revoked
buffers in current transaction any more.
Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Diffstat (limited to 'fs/jbd2/revoke.c')
| -rw-r--r-- | fs/jbd2/revoke.c | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/fs/jbd2/revoke.c b/fs/jbd2/revoke.c index 69fd93588118..30b2867d6cc9 100644 --- a/fs/jbd2/revoke.c +++ b/fs/jbd2/revoke.c @@ -47,6 +47,10 @@ * overwriting the new data. We don't even need to clear the revoke * bit here. * + * We cache revoke status of a buffer in the current transaction in b_states + * bits. As the name says, revokevalid flag indicates that the cached revoke + * status of a buffer is valid and we can rely on the cached status. + * * Revoke information on buffers is a tri-state value: * * RevokeValid clear: no cached revoke status, need to look it up @@ -478,6 +482,36 @@ int jbd2_journal_cancel_revoke(handle_t *handle, struct journal_head *jh) return did_revoke; } +/* + * journal_clear_revoked_flag clears revoked flag of buffers in + * revoke table to reflect there is no revoked buffers in the next + * transaction which is going to be started. + */ +void jbd2_clear_buffer_revoked_flags(journal_t *journal) +{ + struct jbd2_revoke_table_s *revoke = journal->j_revoke; + int i = 0; + + for (i = 0; i < revoke->hash_size; i++) { + struct list_head *hash_list; + struct list_head *list_entry; + hash_list = &revoke->hash_table[i]; + + list_for_each(list_entry, hash_list) { + struct jbd2_revoke_record_s *record; + struct buffer_head *bh; + record = (struct jbd2_revoke_record_s *)list_entry; + bh = __find_get_block(journal->j_fs_dev, + record->blocknr, + journal->j_blocksize); + if (bh) { + clear_buffer_revoked(bh); + __brelse(bh); + } + } + } +} + /* journal_switch_revoke table select j_revoke for next transaction * we do not want to suspend any processing until all revokes are * written -bzzz |