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-rw-r--r--fs/jbd2/transaction.c74
1 files changed, 59 insertions, 15 deletions
diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index f3d06174b051..6b8338ec2464 100644
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -204,6 +204,20 @@ static int add_transaction_credits(journal_t *journal, int blocks,
* attach this handle to a new transaction.
*/
atomic_sub(total, &t->t_outstanding_credits);
+
+ /*
+ * Is the number of reserved credits in the current transaction too
+ * big to fit this handle? Wait until reserved credits are freed.
+ */
+ if (atomic_read(&journal->j_reserved_credits) + total >
+ journal->j_max_transaction_buffers) {
+ read_unlock(&journal->j_state_lock);
+ wait_event(journal->j_wait_reserved,
+ atomic_read(&journal->j_reserved_credits) + total <=
+ journal->j_max_transaction_buffers);
+ return 1;
+ }
+
wait_transaction_locked(journal);
return 1;
}
@@ -262,20 +276,24 @@ static int start_this_handle(journal_t *journal, handle_t *handle,
int rsv_blocks = 0;
unsigned long ts = jiffies;
+ if (handle->h_rsv_handle)
+ rsv_blocks = handle->h_rsv_handle->h_buffer_credits;
+
/*
- * 1/2 of transaction can be reserved so we can practically handle
- * only 1/2 of maximum transaction size per operation
+ * Limit the number of reserved credits to 1/2 of maximum transaction
+ * size and limit the number of total credits to not exceed maximum
+ * transaction size per operation.
*/
- if (WARN_ON(blocks > journal->j_max_transaction_buffers / 2)) {
- printk(KERN_ERR "JBD2: %s wants too many credits (%d > %d)\n",
- current->comm, blocks,
- journal->j_max_transaction_buffers / 2);
+ if ((rsv_blocks > journal->j_max_transaction_buffers / 2) ||
+ (rsv_blocks + blocks > journal->j_max_transaction_buffers)) {
+ printk(KERN_ERR "JBD2: %s wants too many credits "
+ "credits:%d rsv_credits:%d max:%d\n",
+ current->comm, blocks, rsv_blocks,
+ journal->j_max_transaction_buffers);
+ WARN_ON(1);
return -ENOSPC;
}
- if (handle->h_rsv_handle)
- rsv_blocks = handle->h_rsv_handle->h_buffer_credits;
-
alloc_transaction:
if (!journal->j_running_transaction) {
/*
@@ -1280,8 +1298,6 @@ void jbd2_buffer_abort_trigger(struct journal_head *jh,
triggers->t_abort(triggers, jh2bh(jh));
}
-
-
/**
* int jbd2_journal_dirty_metadata() - mark a buffer as containing dirty metadata
* @handle: transaction to add buffer to.
@@ -1314,12 +1330,41 @@ int jbd2_journal_dirty_metadata(handle_t *handle, struct buffer_head *bh)
if (is_handle_aborted(handle))
return -EROFS;
- journal = transaction->t_journal;
- jh = jbd2_journal_grab_journal_head(bh);
- if (!jh) {
+ if (!buffer_jbd(bh)) {
ret = -EUCLEAN;
goto out;
}
+ /*
+ * We don't grab jh reference here since the buffer must be part
+ * of the running transaction.
+ */
+ jh = bh2jh(bh);
+ /*
+ * This and the following assertions are unreliable since we may see jh
+ * in inconsistent state unless we grab bh_state lock. But this is
+ * crucial to catch bugs so let's do a reliable check until the
+ * lockless handling is fully proven.
+ */
+ if (jh->b_transaction != transaction &&
+ jh->b_next_transaction != transaction) {
+ jbd_lock_bh_state(bh);
+ J_ASSERT_JH(jh, jh->b_transaction == transaction ||
+ jh->b_next_transaction == transaction);
+ jbd_unlock_bh_state(bh);
+ }
+ if (jh->b_modified == 1) {
+ /* If it's in our transaction it must be in BJ_Metadata list. */
+ if (jh->b_transaction == transaction &&
+ jh->b_jlist != BJ_Metadata) {
+ jbd_lock_bh_state(bh);
+ J_ASSERT_JH(jh, jh->b_transaction != transaction ||
+ jh->b_jlist == BJ_Metadata);
+ jbd_unlock_bh_state(bh);
+ }
+ goto out;
+ }
+
+ journal = transaction->t_journal;
jbd_debug(5, "journal_head %p\n", jh);
JBUFFER_TRACE(jh, "entry");
@@ -1410,7 +1455,6 @@ int jbd2_journal_dirty_metadata(handle_t *handle, struct buffer_head *bh)
spin_unlock(&journal->j_list_lock);
out_unlock_bh:
jbd_unlock_bh_state(bh);
- jbd2_journal_put_journal_head(jh);
out:
JBUFFER_TRACE(jh, "exit");
return ret;