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 91389c8aee8a..42895d369458 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 f2ad061e95ec..0d3814a35ed1 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 8207a01c4edb..01c3901c3a07 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;