Commit 95e05289 authored by Chris Mason's avatar Chris Mason Committed by David Woodhouse
Browse files

Btrfs: Use mount -o subvol to select the subvol directory instead of dev: 



Signed-off-by: default avatarChris Mason <chris.mason@oracle.com>
parent e9fe395e

fs/btrfs/ctree.h

+6 −0
Original line number Diff line number Diff line
@@ -1064,6 +1064,12 @@ static inline int btrfs_set_root_name(struct btrfs_root *root, 
	((type *)(btrfs_leaf_data(leaf) + \

	btrfs_item_offset((leaf)->items + (slot))))



/* mount option defines and helpers */

#define BTRFS_MOUNT_SUBVOL		0x000001

#define btrfs_clear_opt(o, opt)		o &= ~BTRFS_MOUNT_##opt

#define btrfs_set_opt(o, opt)		o |= BTRFS_MOUNT_##opt

#define btrfs_test_opt(sb, opt)		(BTRFS_SB(sb)->s_mount_opt & \

					 BTRFS_MOUNT_##opt)

/* extent-tree.c */

int btrfs_extent_post_op(struct btrfs_trans_handle *trans,

			 struct btrfs_root *root);

fs/btrfs/super.c

+39 −10
Original line number Diff line number Diff line
@@ -33,6 +33,7 @@ 
#include <linux/writeback.h>

#include <linux/statfs.h>

#include <linux/compat.h>

#include <linux/parser.h>

#include "ctree.h"

#include "disk-io.h"

#include "transaction.h"
@@ -58,6 +59,41 @@ static void btrfs_put_super (struct super_block * sb) 
	sb->s_fs_info = NULL;

}



enum {

	Opt_subvol, Opt_err,

};



static match_table_t tokens = {

	{Opt_subvol, "subvol=%s"},

	{Opt_err, NULL}

};



static int parse_options (char * options,

			  struct btrfs_root *root,

			  char **subvol_name)

{

	char * p;

	substring_t args[MAX_OPT_ARGS];

	if (!options)

		return 1;



	while ((p = strsep (&options, ",")) != NULL) {

		int token;

		if (!*p)

			continue;



		token = match_token(p, tokens, args);

		switch (token) {

		case Opt_subvol:

			*subvol_name = match_strdup(&args[0]);

			break;

		default:

			return 0;

		}

	}

	return 1;

}



static int btrfs_fill_super(struct super_block * sb, void * data, int silent)

{

	struct inode * inode;
@@ -250,22 +286,15 @@ int btrfs_get_sb_bdev(struct file_system_type *fs_type, 
/* end copy & paste */



static int btrfs_get_sb(struct file_system_type *fs_type,

	int flags, const char *identifier, void *data, struct vfsmount *mnt)

	int flags, const char *dev_name, void *data, struct vfsmount *mnt)

{

	int ret;

	char *_identifier = kstrdup(identifier, GFP_KERNEL);

	char *subvol_name;

	const char *dev_name;



	subvol_name = _identifier;

	dev_name = strsep(&subvol_name, ":");

	if (!dev_name)

		return -ENOMEM;

	char *subvol_name = NULL;



	parse_options((char *)data, NULL, &subvol_name);

	ret = btrfs_get_sb_bdev(fs_type, flags, dev_name, data,

			btrfs_fill_super, mnt,

			subvol_name ? subvol_name : "default");

	kfree(_identifier);

	return ret;

}