Merge branch 'master' into for-next

Sync with Linus' tree to be able to apply pending patches that
are based on newer code already present upstream.

1 files changed, 19 insertions, 14 deletions

diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c
index 7f21cf3aaf92..eef6979821a4 100644
--- a/fs/jbd2/commit.c
+++ b/fs/jbd2/commit.c
@@ -848,10 +848,16 @@ restart_loop:
         while (commit_transaction->t_forget) {
                 transaction_t *cp_transaction;
                 struct buffer_head *bh;
+                int try_to_free = 0;
 
                 jh = commit_transaction->t_forget;
                 spin_unlock(&journal->j_list_lock);
                 bh = jh2bh(jh);
+                /*
+                 * Get a reference so that bh cannot be freed before we are
+                 * done with it.
+                 */
+                get_bh(bh);
                 jbd_lock_bh_state(bh);
                 J_ASSERT_JH(jh, jh->b_transaction == commit_transaction);
 
@@ -914,28 +920,27 @@ restart_loop:
                         __jbd2_journal_insert_checkpoint(jh, commit_transaction);
                         if (is_journal_aborted(journal))
                                 clear_buffer_jbddirty(bh);
-                        JBUFFER_TRACE(jh, "refile for checkpoint writeback");
-                        __jbd2_journal_refile_buffer(jh);
-                        jbd_unlock_bh_state(bh);
                 } else {
                         J_ASSERT_BH(bh, !buffer_dirty(bh));
-                        /* The buffer on BJ_Forget list and not jbddirty means
+                        /*
+                         * The buffer on BJ_Forget list and not jbddirty means
                          * it has been freed by this transaction and hence it
                          * could not have been reallocated until this
                          * transaction has committed. *BUT* it could be
                          * reallocated once we have written all the data to
                          * disk and before we process the buffer on BJ_Forget
-                         * list. */
-                        JBUFFER_TRACE(jh, "refile or unfile freed buffer");
-                        __jbd2_journal_refile_buffer(jh);
-                        if (!jh->b_transaction) {
-                                jbd_unlock_bh_state(bh);
-                                 /* needs a brelse */
-                                jbd2_journal_remove_journal_head(bh);
-                                release_buffer_page(bh);
-                        } else
-                                jbd_unlock_bh_state(bh);
+                         * list.
+                         */
+                        if (!jh->b_next_transaction)
+                                try_to_free = 1;
                 }
+                JBUFFER_TRACE(jh, "refile or unfile buffer");
+                __jbd2_journal_refile_buffer(jh);
+                jbd_unlock_bh_state(bh);
+                if (try_to_free)
+                        release_buffer_page(bh);        /* Drops bh reference */
+                else
+                        __brelse(bh);
                 cond_resched_lock(&journal->j_list_lock);
         }
         spin_unlock(&journal->j_list_lock);