jbd2: Fix I/O hang in jbd2_journal_release_jbd_inode

[deliverable/linux.git] / fs / jbd2 / commit.c

diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c
index f52e5e8049f195ec461bfb8781584722b5da2562..6494c81e3b0a9cb3d07d2eec52d585e6e3a46117 100644 (file)
--- a/fs/jbd2/commit.c
+++ b/fs/jbd2/commit.c
@@ -26,7 +26,9 @@
 #include <linux/backing-dev.h>
 #include <linux/bio.h>
 #include <linux/blkdev.h>
+#include <linux/bitops.h>
 #include <trace/events/jbd2.h>
+#include <asm/system.h>
 
 /*
  * Default IO end handler for temporary BJ_IO buffer_heads.
@@ -101,7 +103,6 @@ static int journal_submit_commit_record(journal_t *journal,
        struct commit_header *tmp;
        struct buffer_head *bh;
        int ret;
-       int barrier_done = 0;
        struct timespec now = current_kernel_time();
 
        if (is_journal_aborted(journal))
@@ -136,30 +137,22 @@ static int journal_submit_commit_record(journal_t *journal,
        if (journal->j_flags & JBD2_BARRIER &&
            !JBD2_HAS_INCOMPAT_FEATURE(journal,
                                       JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT)) {
-               set_buffer_ordered(bh);
-               barrier_done = 1;
-       }
-       ret = submit_bh(WRITE_SYNC_PLUG, bh);
-       if (barrier_done)
-               clear_buffer_ordered(bh);
-
-       /* is it possible for another commit to fail at roughly
-        * the same time as this one?  If so, we don't want to
-        * trust the barrier flag in the super, but instead want
-        * to remember if we sent a barrier request
-        */
-       if (ret == -EOPNOTSUPP && barrier_done) {
-               printk(KERN_WARNING
-                      "JBD2: Disabling barriers on %s, "
-                      "not supported by device\n", journal->j_devname);
-               write_lock(&journal->j_state_lock);
-               journal->j_flags &= ~JBD2_BARRIER;
-               write_unlock(&journal->j_state_lock);
+               ret = submit_bh(WRITE_SYNC_PLUG | WRITE_BARRIER, bh);
+               if (ret == -EOPNOTSUPP) {
+                       printk(KERN_WARNING
+                              "JBD2: Disabling barriers on %s, "
+                              "not supported by device\n", journal->j_devname);
+                       write_lock(&journal->j_state_lock);
+                       journal->j_flags &= ~JBD2_BARRIER;
+                       write_unlock(&journal->j_state_lock);
 
-               /* And try again, without the barrier */
-               lock_buffer(bh);
-               set_buffer_uptodate(bh);
-               clear_buffer_dirty(bh);
+                       /* And try again, without the barrier */
+                       lock_buffer(bh);
+                       set_buffer_uptodate(bh);
+                       clear_buffer_dirty(bh);
+                       ret = submit_bh(WRITE_SYNC_PLUG, bh);
+               }
+       } else {
                ret = submit_bh(WRITE_SYNC_PLUG, bh);
        }
        *cbh = bh;
@@ -245,7 +238,7 @@ static int journal_submit_data_buffers(journal_t *journal,
        spin_lock(&journal->j_list_lock);
        list_for_each_entry(jinode, &commit_transaction->t_inode_list, i_list) {
                mapping = jinode->i_vfs_inode->i_mapping;
-               jinode->i_flags |= JI_COMMIT_RUNNING;
+               set_bit(__JI_COMMIT_RUNNING, &jinode->i_flags);
                spin_unlock(&journal->j_list_lock);
                /*
                 * submit the inode data buffers. We use writepage
@@ -260,7 +253,8 @@ static int journal_submit_data_buffers(journal_t *journal,
                spin_lock(&journal->j_list_lock);
                J_ASSERT(jinode->i_transaction == commit_transaction);
                commit_transaction->t_flushed_data_blocks = 1;
-               jinode->i_flags &= ~JI_COMMIT_RUNNING;
+               clear_bit(__JI_COMMIT_RUNNING, &jinode->i_flags);
+               smp_mb__after_clear_bit();
                wake_up_bit(&jinode->i_flags, __JI_COMMIT_RUNNING);
        }
        spin_unlock(&journal->j_list_lock);
@@ -281,7 +275,7 @@ static int journal_finish_inode_data_buffers(journal_t *journal,
        /* For locking, see the comment in journal_submit_data_buffers() */
        spin_lock(&journal->j_list_lock);
        list_for_each_entry(jinode, &commit_transaction->t_inode_list, i_list) {
-               jinode->i_flags |= JI_COMMIT_RUNNING;
+               set_bit(__JI_COMMIT_RUNNING, &jinode->i_flags);
                spin_unlock(&journal->j_list_lock);
                err = filemap_fdatawait(jinode->i_vfs_inode->i_mapping);
                if (err) {
@@ -297,7 +291,8 @@ static int journal_finish_inode_data_buffers(journal_t *journal,
                                ret = err;
                }
                spin_lock(&journal->j_list_lock);
-               jinode->i_flags &= ~JI_COMMIT_RUNNING;
+               clear_bit(__JI_COMMIT_RUNNING, &jinode->i_flags);
+               smp_mb__after_clear_bit();
                wake_up_bit(&jinode->i_flags, __JI_COMMIT_RUNNING);
        }