Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (43 commits)
  ext4: Rename ext4dev to ext4
  ext4: Avoid double dirtying of super block in ext4_put_super()
  Update ext4 MAINTAINERS file
  Hook ext4 to the vfs fiemap interface.
  generic block based fiemap implementation
  ocfs2: fiemap support
  vfs: vfs-level fiemap interface
  ext4: fix xattr deadlock
  jbd2: Fix buffer head leak when writing the commit block
  ext4: Add debugging markers that can be used by systemtap
  jbd2: abort instead of waiting for nonexistent transaction
  ext4: fix initialization of UNINIT bitmap blocks
  ext4: Remove old legacy block allocator
  ext4: Use readahead when reading an inode from the inode table
  ext4: Improve the documentation for ext4's /proc tunables
  ext4: Combine proc file handling into a single set of functions
  ext4: move /proc setup and teardown out of mballoc.c
  ext4: Don't use 'struct dentry' for internal lookups
  ext4/jbd2: Avoid WARN() messages when failing to write to the superblock
  ext4: use percpu data structures for lg_prealloc_list
  ...

3 files changed, 72 insertions, 47 deletions

diff --git a/fs/jbd2/checkpoint.c b/fs/jbd2/checkpoint.c
index 91389c8aee8..42895d36945 100644
--- a/fs/jbd2/checkpoint.c
+++ b/fs/jbd2/checkpoint.c
@@ -20,6 +20,7 @@
 #include <linux/time.h>
 #include <linux/fs.h>
 #include <linux/jbd2.h>
+#include <linux/marker.h>
 #include <linux/errno.h>
 #include <linux/slab.h>
 
@@ -126,14 +127,29 @@ void __jbd2_log_wait_for_space(journal_t *journal)
 
 		/*
 		 * Test again, another process may have checkpointed while we
-		 * were waiting for the checkpoint lock
+		 * were waiting for the checkpoint lock. If there are no
+		 * outstanding transactions there is nothing to checkpoint and
+		 * we can't make progress. Abort the journal in this case.
 		 */
 		spin_lock(&journal->j_state_lock);
+		spin_lock(&journal->j_list_lock);
 		nblocks = jbd_space_needed(journal);
 		if (__jbd2_log_space_left(journal) < nblocks) {
+			int chkpt = journal->j_checkpoint_transactions != NULL;
+
+			spin_unlock(&journal->j_list_lock);
 			spin_unlock(&journal->j_state_lock);
-			jbd2_log_do_checkpoint(journal);
+			if (chkpt) {
+				jbd2_log_do_checkpoint(journal);
+			} else {
+				printk(KERN_ERR "%s: no transactions\n",
+				       __func__);
+				jbd2_journal_abort(journal, 0);
+			}
+
 			spin_lock(&journal->j_state_lock);
+		} else {
+			spin_unlock(&journal->j_list_lock);
 		}
 		mutex_unlock(&journal->j_checkpoint_mutex);
 	}
@@ -313,6 +329,8 @@ int jbd2_log_do_checkpoint(journal_t *journal)
 	 * journal straight away.
 	 */
 	result = jbd2_cleanup_journal_tail(journal);
+	trace_mark(jbd2_checkpoint, "dev %s need_checkpoint %d",
+		   journal->j_devname, result);
 	jbd_debug(1, "cleanup_journal_tail returned %d\n", result);
 	if (result <= 0)
 		return result;
diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c
index f2ad061e95e..0d3814a35ed 100644
--- a/fs/jbd2/commit.c
+++ b/fs/jbd2/commit.c
@@ -16,6 +16,7 @@
 #include <linux/time.h>
 #include <linux/fs.h>
 #include <linux/jbd2.h>
+#include <linux/marker.h>
 #include <linux/errno.h>
 #include <linux/slab.h>
 #include <linux/mm.h>
@@ -126,8 +127,7 @@ static int journal_submit_commit_record(journal_t *journal,
 
 	JBUFFER_TRACE(descriptor, "submit commit block");
 	lock_buffer(bh);
-	get_bh(bh);
-	set_buffer_dirty(bh);
+	clear_buffer_dirty(bh);
 	set_buffer_uptodate(bh);
 	bh->b_end_io = journal_end_buffer_io_sync;
 
@@ -147,12 +147,9 @@ static int journal_submit_commit_record(journal_t *journal,
 	 * to remember if we sent a barrier request
 	 */
 	if (ret == -EOPNOTSUPP && barrier_done) {
-		char b[BDEVNAME_SIZE];
-
 		printk(KERN_WARNING
-			"JBD: barrier-based sync failed on %s - "
-			"disabling barriers\n",
-			bdevname(journal->j_dev, b));
+		       "JBD: barrier-based sync failed on %s - "
+		       "disabling barriers\n", journal->j_devname);
 		spin_lock(&journal->j_state_lock);
 		journal->j_flags &= ~JBD2_BARRIER;
 		spin_unlock(&journal->j_state_lock);
@@ -160,7 +157,7 @@ static int journal_submit_commit_record(journal_t *journal,
 		/* And try again, without the barrier */
 		lock_buffer(bh);
 		set_buffer_uptodate(bh);
-		set_buffer_dirty(bh);
+		clear_buffer_dirty(bh);
 		ret = submit_bh(WRITE, bh);
 	}
 	*cbh = bh;
@@ -371,6 +368,8 @@ void jbd2_journal_commit_transaction(journal_t *journal)
 	commit_transaction = journal->j_running_transaction;
 	J_ASSERT(commit_transaction->t_state == T_RUNNING);
 
+	trace_mark(jbd2_start_commit, "dev %s transaction %d",
+		   journal->j_devname, commit_transaction->t_tid);
 	jbd_debug(1, "JBD: starting commit of transaction %d\n",
 			commit_transaction->t_tid);
 
@@ -681,11 +680,9 @@ start_journal_io:
 	 */
 	err = journal_finish_inode_data_buffers(journal, commit_transaction);
 	if (err) {
-		char b[BDEVNAME_SIZE];
-
 		printk(KERN_WARNING
 			"JBD2: Detected IO errors while flushing file data "
-			"on %s\n", bdevname(journal->j_fs_dev, b));
+		       "on %s\n", journal->j_devname);
 		err = 0;
 	}
 
@@ -990,6 +987,9 @@ restart_loop:
 	}
 	spin_unlock(&journal->j_list_lock);
 
+	trace_mark(jbd2_end_commit, "dev %s transaction %d head %d",
+		   journal->j_devname, commit_transaction->t_tid,
+		   journal->j_tail_sequence);
 	jbd_debug(1, "JBD: commit %d complete, head %d\n",
 		  journal->j_commit_sequence, journal->j_tail_sequence);
 
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index 8207a01c4ed..01c3901c3a0 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -597,13 +597,9 @@ int jbd2_journal_bmap(journal_t *journal, unsigned long blocknr,
 		if (ret)
 			*retp = ret;
 		else {
-			char b[BDEVNAME_SIZE];
-
 			printk(KERN_ALERT "%s: journal block not found "
 					"at offset %lu on %s\n",
-				__func__,
-				blocknr,
-				bdevname(journal->j_dev, b));
+			       __func__, blocknr, journal->j_devname);
 			err = -EIO;
 			__journal_abort_soft(journal, err);
 		}
@@ -901,10 +897,7 @@ static struct proc_dir_entry *proc_jbd2_stats;
 
 static void jbd2_stats_proc_init(journal_t *journal)
 {
-	char name[BDEVNAME_SIZE];
-
-	bdevname(journal->j_dev, name);
-	journal->j_proc_entry = proc_mkdir(name, proc_jbd2_stats);
+	journal->j_proc_entry = proc_mkdir(journal->j_devname, proc_jbd2_stats);
 	if (journal->j_proc_entry) {
 		proc_create_data("history", S_IRUGO, journal->j_proc_entry,
 				 &jbd2_seq_history_fops, journal);
@@ -915,12 +908,9 @@ static void jbd2_stats_proc_init(journal_t *journal)
 
 static void jbd2_stats_proc_exit(journal_t *journal)
 {
-	char name[BDEVNAME_SIZE];
-
-	bdevname(journal->j_dev, name);
 	remove_proc_entry("info", journal->j_proc_entry);
 	remove_proc_entry("history", journal->j_proc_entry);
-	remove_proc_entry(name, proc_jbd2_stats);
+	remove_proc_entry(journal->j_devname, proc_jbd2_stats);
 }
 
 static void journal_init_stats(journal_t *journal)
@@ -1018,6 +1008,7 @@ journal_t * jbd2_journal_init_dev(struct block_device *bdev,
 {
 	journal_t *journal = journal_init_common();
 	struct buffer_head *bh;
+	char *p;
 	int n;
 
 	if (!journal)
@@ -1039,6 +1030,10 @@ journal_t * jbd2_journal_init_dev(struct block_device *bdev,
 	journal->j_fs_dev = fs_dev;
 	journal->j_blk_offset = start;
 	journal->j_maxlen = len;
+	bdevname(journal->j_dev, journal->j_devname);
+	p = journal->j_devname;
+	while ((p = strchr(p, '/')))
+		*p = '!';
 	jbd2_stats_proc_init(journal);
 
 	bh = __getblk(journal->j_dev, start, journal->j_blocksize);
@@ -1061,6 +1056,7 @@ journal_t * jbd2_journal_init_inode (struct inode *inode)
 {
 	struct buffer_head *bh;
 	journal_t *journal = journal_init_common();
+	char *p;
 	int err;
 	int n;
 	unsigned long long blocknr;
@@ -1070,6 +1066,12 @@ journal_t * jbd2_journal_init_inode (struct inode *inode)
 
 	journal->j_dev = journal->j_fs_dev = inode->i_sb->s_bdev;
 	journal->j_inode = inode;
+	bdevname(journal->j_dev, journal->j_devname);
+	p = journal->j_devname;
+	while ((p = strchr(p, '/')))
+		*p = '!';
+	p = journal->j_devname + strlen(journal->j_devname);
+	sprintf(p, ":%lu", journal->j_inode->i_ino);
 	jbd_debug(1,
 		  "journal %p: inode %s/%ld, size %Ld, bits %d, blksize %ld\n",
 		  journal, inode->i_sb->s_id, inode->i_ino,
@@ -1253,6 +1255,22 @@ void jbd2_journal_update_superblock(journal_t *journal, int wait)
 		goto out;
 	}
 
+	if (buffer_write_io_error(bh)) {
+		/*
+		 * Oh, dear.  A previous attempt to write the journal
+		 * superblock failed.  This could happen because the
+		 * USB device was yanked out.  Or it could happen to
+		 * be a transient write error and maybe the block will
+		 * be remapped.  Nothing we can do but to retry the
+		 * write and hope for the best.
+		 */
+		printk(KERN_ERR "JBD2: previous I/O error detected "
+		       "for journal superblock update for %s.\n",
+		       journal->j_devname);
+		clear_buffer_write_io_error(bh);
+		set_buffer_uptodate(bh);
+	}
+
 	spin_lock(&journal->j_state_lock);
 	jbd_debug(1,"JBD: updating superblock (start %ld, seq %d, errno %d)\n",
 		  journal->j_tail, journal->j_tail_sequence, journal->j_errno);
@@ -1264,9 +1282,16 @@ void jbd2_journal_update_superblock(journal_t *journal, int wait)
 
 	BUFFER_TRACE(bh, "marking dirty");
 	mark_buffer_dirty(bh);
-	if (wait)
+	if (wait) {
 		sync_dirty_buffer(bh);
-	else
+		if (buffer_write_io_error(bh)) {
+			printk(KERN_ERR "JBD2: I/O error detected "
+			       "when updating journal superblock for %s.\n",
+			       journal->j_devname);
+			clear_buffer_write_io_error(bh);
+			set_buffer_uptodate(bh);
+		}
+	} else
 		ll_rw_block(SWRITE, 1, &bh);
 
 out:
@@ -1761,23 +1786,6 @@ int jbd2_journal_wipe(journal_t *journal, int write)
 }
 
 /*
- * journal_dev_name: format a character string to describe on what
- * device this journal is present.
- */
-
-static const char *journal_dev_name(journal_t *journal, char *buffer)
-{
-	struct block_device *bdev;
-
-	if (journal->j_inode)
-		bdev = journal->j_inode->i_sb->s_bdev;
-	else
-		bdev = journal->j_dev;
-
-	return bdevname(bdev, buffer);
-}
-
-/*
  * Journal abort has very specific semantics, which we describe
  * for journal abort.
  *
@@ -1793,13 +1801,12 @@ static const char *journal_dev_name(journal_t *journal, char *buffer)
 void __jbd2_journal_abort_hard(journal_t *journal)
 {
 	transaction_t *transaction;
-	char b[BDEVNAME_SIZE];
 
 	if (journal->j_flags & JBD2_ABORT)
 		return;
 
 	printk(KERN_ERR "Aborting journal on device %s.\n",
-		journal_dev_name(journal, b));
+	       journal->j_devname);
 
 	spin_lock(&journal->j_state_lock);
 	journal->j_flags |= JBD2_ABORT;