Merge tag 'upstream-3.5-rc2' of git://git.infradead.org/linux-ubifs

Pull UBI/UBIFS fixes from Artem Bityutskiy:
 "Fix UBI and UBIFS - they refuse to work without debugfs.  This was
  broken by the 3.5-rc1 UBI/UBIFS changes when we removed the debugging
  Kconfig switches.

  Also, correct locking in 'ubi_wl_flush()' - it was extended to support
  flushing a specific LEB in 3.5-rc1, and the locking was sub-optimal."

* tag 'upstream-3.5-rc2' of git://git.infradead.org/linux-ubifs:
  UBI: correct ubi_wl_flush locking
  UBIFS: fix debugfs-less systems support
  UBI: fix debugfs-less systems support

3 files changed, 33 insertions, 8 deletions

diff --git a/drivers/mtd/ubi/debug.c b/drivers/mtd/ubi/debug.c
index 9f957c2d48e..09d4f8d9d59 100644
--- a/drivers/mtd/ubi/debug.c
+++ b/drivers/mtd/ubi/debug.c
@@ -264,6 +264,9 @@ static struct dentry *dfs_rootdir;
  */
 int ubi_debugfs_init(void)
 {
+        if (!IS_ENABLED(DEBUG_FS))
+                return 0;
+
         dfs_rootdir = debugfs_create_dir("ubi", NULL);
         if (IS_ERR_OR_NULL(dfs_rootdir)) {
                 int err = dfs_rootdir ? -ENODEV : PTR_ERR(dfs_rootdir);
@@ -281,7 +284,8 @@ int ubi_debugfs_init(void)
  */
 void ubi_debugfs_exit(void)
 {
-        debugfs_remove(dfs_rootdir);
+        if (IS_ENABLED(DEBUG_FS))
+                debugfs_remove(dfs_rootdir);
 }
 
 /* Read an UBI debugfs file */
@@ -403,6 +407,9 @@ int ubi_debugfs_init_dev(struct ubi_device *ubi)
         struct dentry *dent;
         struct ubi_debug_info *d = ubi->dbg;
 
+        if (!IS_ENABLED(DEBUG_FS))
+                return 0;
+
         n = snprintf(d->dfs_dir_name, UBI_DFS_DIR_LEN + 1, UBI_DFS_DIR_NAME,
                      ubi->ubi_num);
         if (n == UBI_DFS_DIR_LEN) {
@@ -470,5 +477,6 @@ out:
  */
 void ubi_debugfs_exit_dev(struct ubi_device *ubi)
 {
-        debugfs_remove_recursive(ubi->dbg->dfs_dir);
+        if (IS_ENABLED(DEBUG_FS))
+                debugfs_remove_recursive(ubi->dbg->dfs_dir);
 }
diff --git a/drivers/mtd/ubi/wl.c b/drivers/mtd/ubi/wl.c
index 9df100a4ec3..b6be644e7b8 100644
--- a/drivers/mtd/ubi/wl.c
+++ b/drivers/mtd/ubi/wl.c
@@ -1262,11 +1262,11 @@ int ubi_wl_flush(struct ubi_device *ubi, int vol_id, int lnum)
         dbg_wl("flush pending work for LEB %d:%d (%d pending works)",
                vol_id, lnum, ubi->works_count);
 
-        down_write(&ubi->work_sem);
         while (found) {
                 struct ubi_work *wrk;
                 found = 0;
 
+                down_read(&ubi->work_sem);
                 spin_lock(&ubi->wl_lock);
                 list_for_each_entry(wrk, &ubi->works, list) {
                         if ((vol_id == UBI_ALL || wrk->vol_id == vol_id) &&
@@ -1277,18 +1277,27 @@ int ubi_wl_flush(struct ubi_device *ubi, int vol_id, int lnum)
                                 spin_unlock(&ubi->wl_lock);
 
                                 err = wrk->func(ubi, wrk, 0);
-                                if (err)
-                                        goto out;
+                                if (err) {
+                                        up_read(&ubi->work_sem);
+                                        return err;
+                                }
+
                                 spin_lock(&ubi->wl_lock);
                                 found = 1;
                                 break;
                         }
                 }
                 spin_unlock(&ubi->wl_lock);
+                up_read(&ubi->work_sem);
         }
 
-out:
+        /*
+         * Make sure all the works which have been done in parallel are
+         * finished.
+         */
+        down_write(&ubi->work_sem);
         up_write(&ubi->work_sem);
+
         return err;
 }
 
diff --git a/fs/ubifs/debug.c b/fs/ubifs/debug.c
index 685a83756b2..84a7e6f3c04 100644
--- a/fs/ubifs/debug.c
+++ b/fs/ubifs/debug.c
@@ -2918,6 +2918,9 @@ int dbg_debugfs_init_fs(struct ubifs_info *c)
         struct dentry *dent;
         struct ubifs_debug_info *d = c->dbg;
 
+        if (!IS_ENABLED(DEBUG_FS))
+                return 0;
+
         n = snprintf(d->dfs_dir_name, UBIFS_DFS_DIR_LEN + 1, UBIFS_DFS_DIR_NAME,
                      c->vi.ubi_num, c->vi.vol_id);
         if (n == UBIFS_DFS_DIR_LEN) {
@@ -3010,7 +3013,8 @@ out:
  */
 void dbg_debugfs_exit_fs(struct ubifs_info *c)
 {
-        debugfs_remove_recursive(c->dbg->dfs_dir);
+        if (IS_ENABLED(DEBUG_FS))
+                debugfs_remove_recursive(c->dbg->dfs_dir);
 }
 
 struct ubifs_global_debug_info ubifs_dbg;
@@ -3095,6 +3099,9 @@ int dbg_debugfs_init(void)
         const char *fname;
         struct dentry *dent;
 
+        if (!IS_ENABLED(DEBUG_FS))
+                return 0;
+
         fname = "ubifs";
         dent = debugfs_create_dir(fname, NULL);
         if (IS_ERR_OR_NULL(dent))
@@ -3159,7 +3166,8 @@ out:
  */
 void dbg_debugfs_exit(void)
 {
-        debugfs_remove_recursive(dfs_rootdir);
+        if (IS_ENABLED(DEBUG_FS))
+                debugfs_remove_recursive(dfs_rootdir);
 }
 
 /**