[readdir] switch dcache_readdir() users to ->iterate()

new helpers - dir_emit_dot(file, ctx, dentry), dir_emit_dotdot(file, ctx),
dir_emit_dots(file, ctx).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

arch/powerpc/platforms/cell/spufs/inode.c

@@ -238,7 +238,7 @@ const struct file_operations spufs_context_fops = {
 	.release	= spufs_dir_close,
 	.llseek		= dcache_dir_lseek,
 	.read		= generic_read_dir,
-	.readdir	= dcache_readdir,
+	.iterate	= dcache_readdir,
 	.fsync		= noop_fsync,
 };
 EXPORT_SYMBOL_GPL(spufs_context_fops);

fs/autofs4/root.c

@@ -41,7 +41,7 @@ const struct file_operations autofs4_root_operations = {
 	.open		= dcache_dir_open,
 	.release	= dcache_dir_close,
 	.read		= generic_read_dir,
-	.readdir	= dcache_readdir,
+	.iterate	= dcache_readdir,
 	.llseek		= dcache_dir_lseek,
 	.unlocked_ioctl	= autofs4_root_ioctl,
 #ifdef CONFIG_COMPAT
@@ -53,7 +53,7 @@ const struct file_operations autofs4_dir_operations = {
 	.open		= autofs4_dir_open,
 	.release	= dcache_dir_close,
 	.read		= generic_read_dir,
-	.readdir	= dcache_readdir,
+	.iterate	= dcache_readdir,
 	.llseek		= dcache_dir_lseek,
 };
 

fs/libfs.c

@@ -135,37 +135,20 @@ static inline unsigned char dt_type(struct inode *inode)
  * both impossible due to the lock on directory.
  */
 
-int dcache_readdir(struct file * filp, void * dirent, filldir_t filldir)
+int dcache_readdir(struct file *file, struct dir_context *ctx)
 {
-	struct dentry *dentry = filp->f_path.dentry;
-	struct dentry *cursor = filp->private_data;
+	struct dentry *dentry = file->f_path.dentry;
+	struct dentry *cursor = file->private_data;
 	struct list_head *p, *q = &cursor->d_u.d_child;
-	ino_t ino;
-	int i = filp->f_pos;
 
-	switch (i) {
-		case 0:
-			ino = dentry->d_inode->i_ino;
-			if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
-				break;
-			filp->f_pos++;
-			i++;
-			/* fallthrough */
-		case 1:
-			ino = parent_ino(dentry);
-			if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
-				break;
-			filp->f_pos++;
-			i++;
-			/* fallthrough */
-		default:
+	if (!dir_emit_dots(file, ctx))
+		return 0;
 	spin_lock(&dentry->d_lock);
-			if (filp->f_pos == 2)
+	if (ctx->pos == 2)
 		list_move(q, &dentry->d_subdirs);
 
-			for (p=q->next; p != &dentry->d_subdirs; p=p->next) {
-				struct dentry *next;
-				next = list_entry(p, struct dentry, d_u.d_child);
+	for (p = q->next; p != &dentry->d_subdirs; p = p->next) {
+		struct dentry *next = list_entry(p, struct dentry, d_u.d_child);
 		spin_lock_nested(&next->d_lock, DENTRY_D_LOCK_NESTED);
 		if (!simple_positive(next)) {
 			spin_unlock(&next->d_lock);
@@ -174,10 +157,8 @@ int dcache_readdir(struct file * filp, void * dirent, filldir_t filldir)
 
 		spin_unlock(&next->d_lock);
 		spin_unlock(&dentry->d_lock);
-				if (filldir(dirent, next->d_name.name, 
-					    next->d_name.len, filp->f_pos, 
-					    next->d_inode->i_ino, 
-					    dt_type(next->d_inode)) < 0)
+		if (!dir_emit(ctx, next->d_name.name, next->d_name.len,
+			      next->d_inode->i_ino, dt_type(next->d_inode)))
 			return 0;
 		spin_lock(&dentry->d_lock);
 		spin_lock_nested(&next->d_lock, DENTRY_D_LOCK_NESTED);
@@ -185,10 +166,9 @@ int dcache_readdir(struct file * filp, void * dirent, filldir_t filldir)
 		list_move(q, p);
 		spin_unlock(&next->d_lock);
 		p = q;
-				filp->f_pos++;
+		ctx->pos++;
 	}
 	spin_unlock(&dentry->d_lock);
-	}
 	return 0;
 }
 
@@ -202,7 +182,7 @@ const struct file_operations simple_dir_operations = {
 	.release	= dcache_dir_close,
 	.llseek		= dcache_dir_lseek,
 	.read		= generic_read_dir,
-	.readdir	= dcache_readdir,
+	.iterate	= dcache_readdir,
 	.fsync		= noop_fsync,
 };
 

include/linux/fs.h

@@ -1511,12 +1511,6 @@ struct dir_context {
 	loff_t pos;
 };
 
-static inline bool dir_emit(struct dir_context *ctx,
-			    const char *name, int namelen,
-			    u64 ino, unsigned type)
-{
-	return ctx->actor(ctx, name, namelen, ctx->pos, ino, type) == 0;
-}
 struct block_device_operations;
 
 /* These macros are for out of kernel modules to test that
@@ -2537,7 +2531,7 @@ extern void iterate_supers_type(struct file_system_type *,
 extern int dcache_dir_open(struct inode *, struct file *);
 extern int dcache_dir_close(struct inode *, struct file *);
 extern loff_t dcache_dir_lseek(struct file *, loff_t, int);
-extern int dcache_readdir(struct file *, void *, filldir_t);
+extern int dcache_readdir(struct file *, struct dir_context *);
 extern int simple_setattr(struct dentry *, struct iattr *);
 extern int simple_getattr(struct vfsmount *, struct dentry *, struct kstat *);
 extern int simple_statfs(struct dentry *, struct kstatfs *);
@@ -2701,4 +2695,35 @@ static inline void inode_has_no_xattr(struct inode *inode)
 		inode->i_flags |= S_NOSEC;
 }
 
+static inline bool dir_emit(struct dir_context *ctx,
+			    const char *name, int namelen,
+			    u64 ino, unsigned type)
+{
+	return ctx->actor(ctx, name, namelen, ctx->pos, ino, type) == 0;
+}
+static inline bool dir_emit_dot(struct file *file, struct dir_context *ctx)
+{
+	return ctx->actor(ctx, ".", 1, ctx->pos,
+			  file->f_path.dentry->d_inode->i_ino, DT_DIR) == 0;
+}
+static inline bool dir_emit_dotdot(struct file *file, struct dir_context *ctx)
+{
+	return ctx->actor(ctx, "..", 2, ctx->pos,
+			  parent_ino(file->f_path.dentry), DT_DIR) == 0;
+}
+static inline bool dir_emit_dots(struct file *file, struct dir_context *ctx)
+{
+	if (ctx->pos == 0) {
+		if (!dir_emit_dot(file, ctx))
+			return false;
+		ctx->pos = 1;
+	}
+	if (ctx->pos == 1) {
+		if (!dir_emit_dotdot(file, ctx))
+			return false;
+		ctx->pos = 2;
+	}
+	return true;
+}
+
 #endif /* _LINUX_FS_H */