btrfs: clean up transaction abort messages

The transaction abort stacktrace is printed only once per module
lifetime, but we'd like to see it each time it happens per mounted
filesystem.  Introduce a fs_state flag that records it.

Tweak the messages around abort:
* add error number to the first abort
* print the exact negative errno from btrfs_decode_error
* clean up btrfs_decode_error and callers
* no dots at the end of the messages

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

1 files changed, 22 insertions, 25 deletions

diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 8168ceca4754..7f00a91ccc10 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -64,9 +64,9 @@
 static const struct super_operations btrfs_super_ops;
 static struct file_system_type btrfs_fs_type;
 
-static const char *btrfs_decode_error(int errno, char nbuf[16])
+static const char *btrfs_decode_error(int errno)
 {
-        char *errstr = NULL;
+        char *errstr = "unknown";
 
         switch (errno) {
         case -EIO:
@@ -81,12 +81,6 @@ static const char *btrfs_decode_error(int errno, char nbuf[16])
         case -EEXIST:
                 errstr = "Object already exists";
                 break;
-        default:
-                if (nbuf) {
-                        if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
-                                errstr = nbuf;
-                }
-                break;
         }
 
         return errstr;
@@ -122,7 +116,6 @@ static void btrfs_handle_error(struct btrfs_fs_info *fs_info)
                  * mounted writeable again, the device replace
                  * operation continues.
                  */
-//              WARN_ON(1);
         }
 }
 
@@ -135,7 +128,6 @@ void __btrfs_std_error(struct btrfs_fs_info *fs_info, const char *function,
                        unsigned int line, int errno, const char *fmt, ...)
 {
         struct super_block *sb = fs_info->sb;
-        char nbuf[16];
         const char *errstr;
 
         /*
@@ -145,7 +137,7 @@ void __btrfs_std_error(struct btrfs_fs_info *fs_info, const char *function,
         if (errno == -EROFS && (sb->s_flags & MS_RDONLY))
                 return;
 
-        errstr = btrfs_decode_error(errno, nbuf);
+        errstr = btrfs_decode_error(errno);
         if (fmt) {
                 struct va_format vaf;
                 va_list args;
@@ -154,12 +146,12 @@ void __btrfs_std_error(struct btrfs_fs_info *fs_info, const char *function,
                 vaf.fmt = fmt;
                 vaf.va = &args;
 
-                printk(KERN_CRIT "BTRFS error (device %s) in %s:%d: %s (%pV)\n",
-                        sb->s_id, function, line, errstr, &vaf);
+                printk(KERN_CRIT "BTRFS error (device %s) in %s:%d: errno=%d %s (%pV)\n",
+                        sb->s_id, function, line, errno, errstr, &vaf);
                 va_end(args);
         } else {
-                printk(KERN_CRIT "BTRFS error (device %s) in %s:%d: %s\n",
-                        sb->s_id, function, line, errstr);
+                printk(KERN_CRIT "BTRFS error (device %s) in %s:%d: errno=%d %s\n",
+                        sb->s_id, function, line, errno, errstr);
         }
 
         /* Don't go through full error handling during mount */
@@ -248,17 +240,23 @@ void __btrfs_abort_transaction(struct btrfs_trans_handle *trans,
                                struct btrfs_root *root, const char *function,
                                unsigned int line, int errno)
 {
-        WARN_ONCE(1, KERN_DEBUG "btrfs: Transaction aborted\n");
+        /*
+         * Report first abort since mount
+         */
+        if (!test_and_set_bit(BTRFS_FS_STATE_TRANS_ABORTED,
+                                &root->fs_info->fs_state)) {
+                WARN(1, KERN_DEBUG "btrfs: Transaction aborted (error %d)\n",
+                                errno);
+        }
         trans->aborted = errno;
         /* Nothing used. The other threads that have joined this
          * transaction may be able to continue. */
         if (!trans->blocks_used) {
-                char nbuf[16];
                 const char *errstr;
 
-                errstr = btrfs_decode_error(errno, nbuf);
+                errstr = btrfs_decode_error(errno);
                 btrfs_printk(root->fs_info,
-                             "%s:%d: Aborting unused transaction(%s).\n",
+                             "%s:%d: Aborting unused transaction (%s)\n",
                              function, line, errstr);
                 return;
         }
@@ -272,7 +270,6 @@ void __btrfs_abort_transaction(struct btrfs_trans_handle *trans,
 void __btrfs_panic(struct btrfs_fs_info *fs_info, const char *function,
                    unsigned int line, int errno, const char *fmt, ...)
 {
-        char nbuf[16];
         char *s_id = "<unknown>";
         const char *errstr;
         struct va_format vaf = { .fmt = fmt };
@@ -284,13 +281,13 @@ void __btrfs_panic(struct btrfs_fs_info *fs_info, const char *function,
         va_start(args, fmt);
         vaf.va = &args;
 
-        errstr = btrfs_decode_error(errno, nbuf);
+        errstr = btrfs_decode_error(errno);
         if (fs_info && (fs_info->mount_opt & BTRFS_MOUNT_PANIC_ON_FATAL_ERROR))
-                panic(KERN_CRIT "BTRFS panic (device %s) in %s:%d: %pV (%s)\n",
-                        s_id, function, line, &vaf, errstr);
+                panic(KERN_CRIT "BTRFS panic (device %s) in %s:%d: %pV (errno=%d %s)\n",
+                        s_id, function, line, &vaf, errno, errstr);
 
-        printk(KERN_CRIT "BTRFS panic (device %s) in %s:%d: %pV (%s)\n",
-               s_id, function, line, &vaf, errstr);
+        printk(KERN_CRIT "BTRFS panic (device %s) in %s:%d: %pV (errno=%d %s)\n",
+               s_id, function, line, &vaf, errno, errstr);
         va_end(args);
         /* Caller calls BUG() */
 }