Merge tag 'at91-dt' of git://git.kernel.org/pub/scm/linux/kernel/git/nferre/linux...

[cascardo/linux.git] / fs / overlayfs / readdir.c

diff --git a/fs/overlayfs/readdir.c b/fs/overlayfs/readdir.c
index 910553f..4e9d7c1 100644 (file)
--- a/fs/overlayfs/readdir.c
+++ b/fs/overlayfs/readdir.c
@@ -21,9 +21,10 @@ struct ovl_cache_entry {
        unsigned int len;
        unsigned int type;
        u64 ino;
-       bool is_whiteout;
        struct list_head l_node;
        struct rb_node node;
+       bool is_whiteout;
+       bool is_cursor;
        char name[];
 };
 
@@ -92,6 +93,7 @@ static struct ovl_cache_entry *ovl_cache_entry_new(const char *name, int len,
                p->type = d_type;
                p->ino = ino;
                p->is_whiteout = false;
+               p->is_cursor = false;
        }
 
        return p;
@@ -251,7 +253,7 @@ static int ovl_dir_mark_whiteouts(struct dentry *dir,
 
        mutex_lock(&dir->d_inode->i_mutex);
        list_for_each_entry(p, rdd->list, l_node) {
-               if (!p->name)
+               if (p->is_cursor)
                        continue;
 
                if (p->type != DT_CHR)
@@ -307,7 +309,6 @@ static inline int ovl_dir_read_merged(struct path *upperpath,
        }
 out:
        return err;
-
 }
 
 static void ovl_seek_cursor(struct ovl_dir_file *od, loff_t pos)
@@ -316,7 +317,7 @@ static void ovl_seek_cursor(struct ovl_dir_file *od, loff_t pos)
        loff_t off = 0;
 
        list_for_each_entry(p, &od->cache->entries, l_node) {
-               if (!p->name)
+               if (p->is_cursor)
                        continue;
                if (off >= pos)
                        break;
@@ -389,7 +390,7 @@ static int ovl_iterate(struct file *file, struct dir_context *ctx)
 
                p = list_entry(od->cursor.l_node.next, struct ovl_cache_entry, l_node);
                /* Skip cursors */
-               if (p->name) {
+               if (!p->is_cursor) {
                        if (!p->is_whiteout) {
                                if (!dir_emit(ctx, p->name, p->len, p->ino, p->type))
                                        break;
@@ -454,12 +455,13 @@ static int ovl_dir_fsync(struct file *file, loff_t start, loff_t end,
        if (!od->is_upper && ovl_path_type(dentry) == OVL_PATH_MERGE) {
                struct inode *inode = file_inode(file);
 
-               realfile = od->upperfile;
+               realfile =lockless_dereference(od->upperfile);
                if (!realfile) {
                        struct path upperpath;
 
                        ovl_path_upper(dentry, &upperpath);
                        realfile = ovl_path_open(&upperpath, O_RDONLY);
+                       smp_mb__before_spinlock();
                        mutex_lock(&inode->i_mutex);
                        if (!od->upperfile) {
                                if (IS_ERR(realfile)) {
@@ -518,6 +520,7 @@ static int ovl_dir_open(struct inode *inode, struct file *file)
        od->realfile = realfile;
        od->is_real = (type != OVL_PATH_MERGE);
        od->is_upper = (type != OVL_PATH_LOWER);
+       od->cursor.is_cursor = true;
        file->private_data = od;
 
        return 0;
@@ -569,7 +572,7 @@ void ovl_cleanup_whiteouts(struct dentry *upper, struct list_head *list)
 {
        struct ovl_cache_entry *p;
 
-       mutex_lock_nested(&upper->d_inode->i_mutex, I_MUTEX_PARENT);
+       mutex_lock_nested(&upper->d_inode->i_mutex, I_MUTEX_CHILD);
        list_for_each_entry(p, list, l_node) {
                struct dentry *dentry;