1 files changed, 87 insertions, 39 deletions

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 203f9e4a70be..8553dfb310af 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -54,9 +54,9 @@
 
 static struct proc_dir_entry *ext4_proc_root;
 static struct kset *ext4_kset;
-struct ext4_lazy_init *ext4_li_info;
-struct mutex ext4_li_mtx;
-struct ext4_features *ext4_feat;
+static struct ext4_lazy_init *ext4_li_info;
+static struct mutex ext4_li_mtx;
+static struct ext4_features *ext4_feat;
 
 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
                              unsigned long journal_devnum);
@@ -75,6 +75,7 @@ static void ext4_write_super(struct super_block *sb);
 static int ext4_freeze(struct super_block *sb);
 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
                        const char *dev_name, void *data);
+static int ext4_feature_set_ok(struct super_block *sb, int readonly);
 static void ext4_destroy_lazyinit_thread(void);
 static void ext4_unregister_li_request(struct super_block *sb);
 static void ext4_clear_request_list(void);
@@ -241,27 +242,44 @@ static void ext4_put_nojournal(handle_t *handle)
  * journal_end calls result in the superblock being marked dirty, so
  * that sync() will call the filesystem's write_super callback if
  * appropriate.
+ *
+ * To avoid j_barrier hold in userspace when a user calls freeze(),
+ * ext4 prevents a new handle from being started by s_frozen, which
+ * is in an upper layer.
  */
 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
 {
         journal_t *journal;
+        handle_t  *handle;
 
         if (sb->s_flags & MS_RDONLY)
                 return ERR_PTR(-EROFS);
 
-        vfs_check_frozen(sb, SB_FREEZE_TRANS);
-        /* Special case here: if the journal has aborted behind our
-         * backs (eg. EIO in the commit thread), then we still need to
-         * take the FS itself readonly cleanly. */
         journal = EXT4_SB(sb)->s_journal;
-        if (journal) {
-                if (is_journal_aborted(journal)) {
-                        ext4_abort(sb, "Detected aborted journal");
-                        return ERR_PTR(-EROFS);
-                }
-                return jbd2_journal_start(journal, nblocks);
+        handle = ext4_journal_current_handle();
+
+        /*
+         * If a handle has been started, it should be allowed to
+         * finish, otherwise deadlock could happen between freeze
+         * and others(e.g. truncate) due to the restart of the
+         * journal handle if the filesystem is forzen and active
+         * handles are not stopped.
+         */
+        if (!handle)
+                vfs_check_frozen(sb, SB_FREEZE_TRANS);
+
+        if (!journal)
+                return ext4_get_nojournal();
+        /*
+         * Special case here: if the journal has aborted behind our
+         * backs (eg. EIO in the commit thread), then we still need to
+         * take the FS itself readonly cleanly.
+         */
+        if (is_journal_aborted(journal)) {
+                ext4_abort(sb, "Detected aborted journal");
+                return ERR_PTR(-EROFS);
         }
-        return ext4_get_nojournal();
+        return jbd2_journal_start(journal, nblocks);
 }
 
 /*
@@ -594,7 +612,7 @@ __acquires(bitlock)
 
         vaf.fmt = fmt;
         vaf.va = &args;
-        printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u",
+        printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
                sb->s_id, function, line, grp);
         if (ino)
                 printk(KERN_CONT "inode %lu: ", ino);
@@ -616,7 +634,7 @@ __acquires(bitlock)
          * filesystem will have already been marked read/only and the
          * journal has been aborted.  We return 1 as a hint to callers
          * who might what to use the return value from
-         * ext4_grp_locked_error() to distinguish beween the
+         * ext4_grp_locked_error() to distinguish between the
          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
          * aggressively from the ext4 function in question, with a
          * more appropriate error code.
@@ -997,13 +1015,10 @@ static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
         if (test_opt(sb, OLDALLOC))
                 seq_puts(seq, ",oldalloc");
 #ifdef CONFIG_EXT4_FS_XATTR
-        if (test_opt(sb, XATTR_USER) &&
-                !(def_mount_opts & EXT4_DEFM_XATTR_USER))
+        if (test_opt(sb, XATTR_USER))
                 seq_puts(seq, ",user_xattr");
-        if (!test_opt(sb, XATTR_USER) &&
-            (def_mount_opts & EXT4_DEFM_XATTR_USER)) {
+        if (!test_opt(sb, XATTR_USER))
                 seq_puts(seq, ",nouser_xattr");
-        }
 #endif
 #ifdef CONFIG_EXT4_FS_POSIX_ACL
         if (test_opt(sb, POSIX_ACL) && !(def_mount_opts & EXT4_DEFM_ACL))
@@ -1041,8 +1056,8 @@ static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
             !(def_mount_opts & EXT4_DEFM_NODELALLOC))
                 seq_puts(seq, ",nodelalloc");
 
-        if (test_opt(sb, MBLK_IO_SUBMIT))
-                seq_puts(seq, ",mblk_io_submit");
+        if (!test_opt(sb, MBLK_IO_SUBMIT))
+                seq_puts(seq, ",nomblk_io_submit");
         if (sbi->s_stripe)
                 seq_printf(seq, ",stripe=%lu", sbi->s_stripe);
         /*
@@ -1451,7 +1466,7 @@ static int parse_options(char *options, struct super_block *sb,
                  * Initialize args struct so we know whether arg was
                  * found; some options take optional arguments.
                  */
-                args[0].to = args[0].from = 0;
+                args[0].to = args[0].from = NULL;
                 token = match_token(p, tokens, args);
                 switch (token) {
                 case Opt_bsd_df:
@@ -1771,7 +1786,7 @@ set_qf_format:
                                 return 0;
                         if (option < 0 || option > (1 << 30))
                                 return 0;
-                        if (!is_power_of_2(option)) {
+                        if (option && !is_power_of_2(option)) {
                                 ext4_msg(sb, KERN_ERR,
                                          "EXT4-fs: inode_readahead_blks"
                                          " must be a power of 2");
@@ -2120,6 +2135,13 @@ static void ext4_orphan_cleanup(struct super_block *sb,
                 return;
         }
 
+        /* Check if feature set would not allow a r/w mount */
+        if (!ext4_feature_set_ok(sb, 0)) {
+                ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
+                         "unknown ROCOMPAT features");
+                return;
+        }
+
         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
                 if (es->s_last_orphan)
                         jbd_debug(1, "Errors on filesystem, "
@@ -2412,7 +2434,7 @@ static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
         if (parse_strtoul(buf, 0x40000000, &t))
                 return -EINVAL;
 
-        if (!is_power_of_2(t))
+        if (t && !is_power_of_2(t))
                 return -EINVAL;
 
         sbi->s_inode_readahead_blks = t;
@@ -2970,6 +2992,12 @@ static int ext4_register_li_request(struct super_block *sb,
         mutex_unlock(&ext4_li_info->li_list_mtx);
 
         sbi->s_li_request = elr;
+        /*
+         * set elr to NULL here since it has been inserted to
+         * the request_list and the removal and free of it is
+         * handled by ext4_clear_request_list from now on.
+         */
+        elr = NULL;
 
         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
                 ret = ext4_run_lazyinit_thread();
@@ -3095,14 +3123,14 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
         }
         if (def_mount_opts & EXT4_DEFM_UID16)
                 set_opt(sb, NO_UID32);
+        /* xattr user namespace & acls are now defaulted on */
 #ifdef CONFIG_EXT4_FS_XATTR
-        if (def_mount_opts & EXT4_DEFM_XATTR_USER)
-                set_opt(sb, XATTR_USER);
+        set_opt(sb, XATTR_USER);
 #endif
 #ifdef CONFIG_EXT4_FS_POSIX_ACL
-        if (def_mount_opts & EXT4_DEFM_ACL)
-                set_opt(sb, POSIX_ACL);
+        set_opt(sb, POSIX_ACL);
 #endif
+        set_opt(sb, MBLK_IO_SUBMIT);
         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
                 set_opt(sb, JOURNAL_DATA);
         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
@@ -3380,6 +3408,10 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
         spin_lock_init(&sbi->s_next_gen_lock);
 
+        init_timer(&sbi->s_err_report);
+        sbi->s_err_report.function = print_daily_error_info;
+        sbi->s_err_report.data = (unsigned long) sb;
+
         err = percpu_counter_init(&sbi->s_freeblocks_counter,
                         ext4_count_free_blocks(sb));
         if (!err) {
@@ -3516,7 +3548,7 @@ no_journal:
          * concurrency isn't really necessary.  Limit it to 1.
          */
         EXT4_SB(sb)->dio_unwritten_wq =
-                alloc_workqueue("ext4-dio-unwritten", WQ_MEM_RECLAIM, 1);
+                alloc_workqueue("ext4-dio-unwritten", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
         if (!EXT4_SB(sb)->dio_unwritten_wq) {
                 printk(KERN_ERR "EXT4-fs: failed to create DIO workqueue\n");
                 goto failed_mount_wq;
@@ -3531,17 +3563,16 @@ no_journal:
         if (IS_ERR(root)) {
                 ext4_msg(sb, KERN_ERR, "get root inode failed");
                 ret = PTR_ERR(root);
+                root = NULL;
                 goto failed_mount4;
         }
         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
-                iput(root);
                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
                 goto failed_mount4;
         }
         sb->s_root = d_alloc_root(root);
         if (!sb->s_root) {
                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
-                iput(root);
                 ret = -ENOMEM;
                 goto failed_mount4;
         }
@@ -3642,9 +3673,6 @@ no_journal:
                  "Opts: %s%s%s", descr, sbi->s_es->s_mount_opts,
                  *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
 
-        init_timer(&sbi->s_err_report);
-        sbi->s_err_report.function = print_daily_error_info;
-        sbi->s_err_report.data = (unsigned long) sb;
         if (es->s_error_count)
                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
 
@@ -3657,6 +3685,8 @@ cantfind_ext4:
         goto failed_mount;
 
 failed_mount4:
+        iput(root);
+        sb->s_root = NULL;
         ext4_msg(sb, KERN_ERR, "mount failed");
         destroy_workqueue(EXT4_SB(sb)->dio_unwritten_wq);
 failed_mount_wq:
@@ -3666,6 +3696,7 @@ failed_mount_wq:
                 sbi->s_journal = NULL;
         }
 failed_mount3:
+        del_timer(&sbi->s_err_report);
         if (sbi->s_flex_groups) {
                 if (is_vmalloc_addr(sbi->s_flex_groups))
                         vfree(sbi->s_flex_groups);
@@ -4132,6 +4163,11 @@ static int ext4_sync_fs(struct super_block *sb, int wait)
 /*
  * LVM calls this function before a (read-only) snapshot is created.  This
  * gives us a chance to flush the journal completely and mark the fs clean.
+ *
+ * Note that only this function cannot bring a filesystem to be in a clean
+ * state independently, because ext4 prevents a new handle from being started
+ * by @sb->s_frozen, which stays in an upper layer.  It thus needs help from
+ * the upper layer.
  */
 static int ext4_freeze(struct super_block *sb)
 {
@@ -4608,17 +4644,30 @@ static int ext4_quota_on(struct super_block *sb, int type, int format_id,
 
 static int ext4_quota_off(struct super_block *sb, int type)
 {
+        struct inode *inode = sb_dqopt(sb)->files[type];
+        handle_t *handle;
+
         /* Force all delayed allocation blocks to be allocated.
          * Caller already holds s_umount sem */
         if (test_opt(sb, DELALLOC))
                 sync_filesystem(sb);
 
+        /* Update modification times of quota files when userspace can
+         * start looking at them */
+        handle = ext4_journal_start(inode, 1);
+        if (IS_ERR(handle))
+                goto out;
+        inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+        ext4_mark_inode_dirty(handle, inode);
+        ext4_journal_stop(handle);
+
+out:
         return dquot_quota_off(sb, type);
 }
 
 /* Read data from quotafile - avoid pagecache and such because we cannot afford
  * acquiring the locks... As quota files are never truncated and quota code
- * itself serializes the operations (and noone else should touch the files)
+ * itself serializes the operations (and no one else should touch the files)
  * we don't have to be afraid of races */
 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
                                size_t len, loff_t off)
@@ -4708,9 +4757,8 @@ out:
         if (inode->i_size < off + len) {
                 i_size_write(inode, off + len);
                 EXT4_I(inode)->i_disksize = inode->i_size;
+                ext4_mark_inode_dirty(handle, inode);
         }
-        inode->i_mtime = inode->i_ctime = CURRENT_TIME;
-        ext4_mark_inode_dirty(handle, inode);
         mutex_unlock(&inode->i_mutex);
         return len;
 }