diff options
| -rw-r--r-- | fs/jbd2/transaction.c | 19 |
1 files changed, 18 insertions, 1 deletions
diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c index 8804e126805f..5347411ae13e 100644 --- a/fs/jbd2/transaction.c +++ b/fs/jbd2/transaction.c @@ -223,9 +223,15 @@ static void sub_reserved_credits(journal_t *journal, int blocks) * with j_state_lock held for reading. Returns 0 if handle joined the running * transaction. Returns 1 if we had to wait, j_state_lock is dropped, and * caller must retry. + * + * Note: because j_state_lock may be dropped depending on the return + * value, we need to fake out sparse so ti doesn't complain about a + * locking imbalance. Callers of add_transaction_credits will need to + * make a similar accomodation. */ static int add_transaction_credits(journal_t *journal, int blocks, int rsv_blocks) +__must_hold(&journal->j_state_lock) { transaction_t *t = journal->j_running_transaction; int needed; @@ -238,6 +244,7 @@ static int add_transaction_credits(journal_t *journal, int blocks, if (t->t_state != T_RUNNING) { WARN_ON_ONCE(t->t_state >= T_FLUSH); wait_transaction_locked(journal); + __acquire(&journal->j_state_lock); /* fake out sparse */ return 1; } @@ -266,10 +273,12 @@ static int add_transaction_credits(journal_t *journal, int blocks, wait_event(journal->j_wait_reserved, atomic_read(&journal->j_reserved_credits) + total <= journal->j_max_transaction_buffers); + __acquire(&journal->j_state_lock); /* fake out sparse */ return 1; } wait_transaction_locked(journal); + __acquire(&journal->j_state_lock); /* fake out sparse */ return 1; } @@ -293,6 +302,7 @@ static int add_transaction_credits(journal_t *journal, int blocks, journal->j_max_transaction_buffers) __jbd2_log_wait_for_space(journal); write_unlock(&journal->j_state_lock); + __acquire(&journal->j_state_lock); /* fake out sparse */ return 1; } @@ -310,6 +320,7 @@ static int add_transaction_credits(journal_t *journal, int blocks, wait_event(journal->j_wait_reserved, atomic_read(&journal->j_reserved_credits) + rsv_blocks <= journal->j_max_transaction_buffers / 2); + __acquire(&journal->j_state_lock); /* fake out sparse */ return 1; } return 0; @@ -413,8 +424,14 @@ repeat: if (!handle->h_reserved) { /* We may have dropped j_state_lock - restart in that case */ - if (add_transaction_credits(journal, blocks, rsv_blocks)) + if (add_transaction_credits(journal, blocks, rsv_blocks)) { + /* + * add_transaction_credits releases + * j_state_lock on a non-zero return + */ + __release(&journal->j_state_lock); goto repeat; + } } else { /* * We have handle reserved so we are allowed to join T_LOCKED |