Commit 33268eaf authored by Josef Bacik's avatar Josef Bacik Committed by Chris Mason
Browse files

Btrfs: Add ACL support 



Signed-off-by: default avatarChris Mason <chris.mason@oracle.com>
parent 6099afe8

fs/btrfs/acl.c

+261 −35
Original line number Diff line number Diff line
@@ -20,76 +20,302 @@ 
#include <linux/string.h>

#include <linux/xattr.h>

#include <linux/posix_acl_xattr.h>

#include <linux/posix_acl.h>

#include <linux/sched.h>



#include "ctree.h"

#include "btrfs_inode.h"

#include "xattr.h"

#ifndef is_owner_or_cap

#define is_owner_or_cap(inode)	\

	((current->fsuid == (inode)->i_uid) || capable(CAP_FOWNER))

#endif



static void btrfs_update_cached_acl(struct inode *inode,

				    struct posix_acl **p_acl,

				    struct posix_acl *acl)

{

	spin_lock(&inode->i_lock);

	if (*p_acl && *p_acl != BTRFS_ACL_NOT_CACHED)

		posix_acl_release(*p_acl);

	*p_acl = posix_acl_dup(acl);

	spin_unlock(&inode->i_lock);

}



static struct posix_acl *btrfs_get_acl(struct inode *inode, int type)

{

	int size, name_index;

	char *value = NULL;

	struct posix_acl *acl = NULL, **p_acl;



	switch (type) {

	case ACL_TYPE_ACCESS:

		name_index = BTRFS_XATTR_INDEX_POSIX_ACL_ACCESS;

		p_acl = &BTRFS_I(inode)->i_acl;

		break;

	case ACL_TYPE_DEFAULT:

		name_index = BTRFS_XATTR_INDEX_POSIX_ACL_DEFAULT;

		p_acl = &BTRFS_I(inode)->i_default_acl;

		break;

	default:

		return ERR_PTR(-EINVAL);

	}



	spin_lock(&inode->i_lock);

	if (*p_acl != BTRFS_ACL_NOT_CACHED)

		acl = posix_acl_dup(*p_acl);

	spin_unlock(&inode->i_lock);



	if (acl)

		return acl;





	size = btrfs_xattr_get(inode, name_index, "", NULL, 0);

	if (size > 0) {

		value = kzalloc(size, GFP_NOFS);

		if (!value)

			return ERR_PTR(-ENOMEM);

		size = btrfs_xattr_get(inode, name_index, "", value, size);

		if (size > 0) {

			acl = posix_acl_from_xattr(value, size);

			btrfs_update_cached_acl(inode, p_acl, acl);

		}

		kfree(value);

	} else if (size == -ENOENT) {

		acl = NULL;

		btrfs_update_cached_acl(inode, p_acl, acl);

	}



	return acl;

}



static int btrfs_xattr_get_acl(struct inode *inode, int type,

			       void *value, size_t size)

{

	struct posix_acl *acl;

	int ret = 0;



	acl = btrfs_get_acl(inode, type);



	if (IS_ERR(acl))

		return PTR_ERR(acl);

	if (acl == NULL)

		return -ENODATA;

	ret = posix_acl_to_xattr(acl, value, size);

	posix_acl_release(acl);



	return ret;

}



/*

 * Needs to be called with fs_mutex held

 */

static int btrfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)

{

	int ret, name_index = 0, size = 0;

	struct posix_acl **p_acl;

	char *value = NULL;

	mode_t mode;



	if (acl) {

		ret = posix_acl_valid(acl);

		if (ret < 0)

			return ret;

		ret = 0;

	}



	switch (type) {

	case ACL_TYPE_ACCESS:

		mode = inode->i_mode;

		ret = posix_acl_equiv_mode(acl, &mode);

		if (ret < 0)

			return ret;

		ret = 0;

		inode->i_mode = mode;

		name_index = BTRFS_XATTR_INDEX_POSIX_ACL_ACCESS;

		p_acl = &BTRFS_I(inode)->i_acl;

		break;

	case ACL_TYPE_DEFAULT:

		if (!S_ISDIR(inode->i_mode))

			return acl ? -EINVAL : 0;

		name_index = BTRFS_XATTR_INDEX_POSIX_ACL_DEFAULT;

		p_acl = &BTRFS_I(inode)->i_default_acl;

		break;

	default:

		return -EINVAL;

	}



	if (acl) {

		size = posix_acl_xattr_size(acl->a_count);

		value = kmalloc(size, GFP_NOFS);

		if (!value) {

			ret = -ENOMEM;

			goto out;

		}



		ret = posix_acl_to_xattr(acl, value, size);

		if (ret < 0)

			goto out;

	}



	ret = btrfs_xattr_set(inode, name_index, "", value, size, 0);



out:

	if (value)

		kfree(value);



	if (!ret)

		btrfs_update_cached_acl(inode, p_acl, acl);



	return ret;

}



static int btrfs_xattr_set_acl(struct inode *inode, int type,

			       const void *value, size_t size)

{

	int ret = 0;

	struct posix_acl *acl;

	struct posix_acl *acl = NULL;



	if (!is_owner_or_cap(inode))

		return -EPERM;

	if (value) {

		acl = posix_acl_from_xattr(value, size);

		if (acl == NULL) {

			value = NULL;

			size = 0;

		} else if (IS_ERR(acl)) {

			ret = PTR_ERR(acl);

		} else {

			ret = posix_acl_valid(acl);

			posix_acl_release(acl);

			return PTR_ERR(acl);

		}

		if (ret)

			return ret;

	}

	return btrfs_xattr_set(inode, type, "", value, size, 0);

	}



static int btrfs_xattr_get_acl(struct inode *inode, int type,

			       void *value, size_t size)

{

	return btrfs_xattr_get(inode, type, "", value, size);

	ret = btrfs_set_acl(inode, acl, type);



	posix_acl_release(acl);



	return ret;

}





static int btrfs_xattr_acl_access_get(struct inode *inode, const char *name,

				      void *value, size_t size)

{

	if (*name != '\0')

	       return -EINVAL;

	return btrfs_xattr_get_acl(inode, BTRFS_XATTR_INDEX_POSIX_ACL_ACCESS,

				   value, size);

	return btrfs_xattr_get_acl(inode, ACL_TYPE_ACCESS, value, size);

}



static int btrfs_xattr_acl_access_set(struct inode *inode, const char *name,

				      const void *value, size_t size, int flags)

{

	if (*name != '\0')

	       return -EINVAL;

	return btrfs_xattr_set_acl(inode, BTRFS_XATTR_INDEX_POSIX_ACL_ACCESS,

				   value, size);

	return btrfs_xattr_set_acl(inode, ACL_TYPE_ACCESS, value, size);

}



static int btrfs_xattr_acl_default_get(struct inode *inode, const char *name,

				       void *value, size_t size)

{

	if (*name != '\0')

	       return -EINVAL;

	return btrfs_xattr_get_acl(inode, BTRFS_XATTR_INDEX_POSIX_ACL_DEFAULT,

				   value, size);

	return btrfs_xattr_get_acl(inode, ACL_TYPE_DEFAULT, value, size);

}



static int btrfs_xattr_acl_default_set(struct inode *inode, const char *name,

				       const void *value, size_t size, int flags)

{

	if (*name != '\0')

	       return -EINVAL;

	return btrfs_xattr_set_acl(inode, BTRFS_XATTR_INDEX_POSIX_ACL_DEFAULT,

				   value, size);

	return btrfs_xattr_set_acl(inode, ACL_TYPE_DEFAULT, value, size);

}



int btrfs_check_acl(struct inode *inode, int mask)

{

	struct posix_acl *acl;

	int error = -EAGAIN;



	acl = btrfs_get_acl(inode, ACL_TYPE_ACCESS);



	if (IS_ERR(acl))

		return PTR_ERR(acl);

	if (acl) {

		error = posix_acl_permission(inode, acl, mask);

		posix_acl_release(acl);

	}



	return error;

}



/*

 * btrfs_init_acl is already generally called under fs_mutex, so the locking

 * stuff has been fixed to work with that.  If the locking stuff changes, we

 * need to re-evaluate the acl locking stuff.

 */

int btrfs_init_acl(struct inode *inode, struct inode *dir)

{

	struct posix_acl *acl = NULL;

	int ret = 0;



	/* this happens with subvols */

	if (!dir)

		return 0;



	if (!S_ISLNK(inode->i_mode)) {

		if (IS_POSIXACL(dir)) {

			acl = btrfs_get_acl(dir, ACL_TYPE_DEFAULT);

			if (IS_ERR(acl))

				return PTR_ERR(acl);

		}



		if (!acl)

			inode->i_mode &= ~current->fs->umask;

	}



	if (IS_POSIXACL(dir) && acl) {

		struct posix_acl *clone;

		mode_t mode;



		if (S_ISDIR(inode->i_mode)) {

			ret = btrfs_set_acl(inode, acl, ACL_TYPE_DEFAULT);

			if (ret)

				goto failed;

		}

		clone = posix_acl_clone(acl, GFP_NOFS);

		ret = -ENOMEM;

		if (!clone)

			goto failed;



		mode = inode->i_mode;

		ret = posix_acl_create_masq(clone, &mode);

		if (ret >= 0) {

			inode->i_mode = mode;

			if (ret > 0) {

				/* we need an acl */

				ret = btrfs_set_acl(inode, clone,

						    ACL_TYPE_ACCESS);

			}

		}

	}

failed:

	posix_acl_release(acl);



	return ret;

}



int btrfs_acl_chmod(struct inode *inode)

{

	struct posix_acl *acl, *clone;

	int ret = 0;



	if (S_ISLNK(inode->i_mode))

		return -EOPNOTSUPP;



	if (!IS_POSIXACL(inode))

		return 0;



	acl = btrfs_get_acl(inode, ACL_TYPE_ACCESS);

	if (IS_ERR(acl) || !acl)

		return PTR_ERR(acl);



	clone = posix_acl_clone(acl, GFP_KERNEL);

	posix_acl_release(acl);

	if (!clone)

		return -ENOMEM;



	ret = posix_acl_chmod_masq(clone, inode->i_mode);

	if (!ret)

		ret = btrfs_set_acl(inode, clone, ACL_TYPE_ACCESS);



	posix_acl_release(clone);



	return ret;

}



struct xattr_handler btrfs_xattr_acl_default_handler = {

	.prefix = POSIX_ACL_XATTR_DEFAULT,

	.list	= btrfs_xattr_generic_list,

fs/btrfs/btrfs_inode.h

+3 −0
Original line number Diff line number Diff line
@@ -36,6 +36,9 @@ struct btrfs_inode { 
	struct inode vfs_inode;

	struct btrfs_ordered_inode_tree ordered_tree;



	struct posix_acl *i_acl;

	struct posix_acl *i_default_acl;



	/*

	 * transid of the trans_handle that last modified this inode

	 */

fs/btrfs/ctree.h

+7 −0
Original line number Diff line number Diff line
@@ -42,6 +42,8 @@ struct btrfs_ordered_sum; 


#define BTRFS_MAGIC "_B5RfS_M"



#define BTRFS_ACL_NOT_CACHED    ((void *)-1)



#ifdef CONFIG_LOCKDEP

# define BTRFS_MAX_LEVEL 7

#else
@@ -1694,4 +1696,9 @@ ssize_t btrfs_listxattr(struct dentry *dentry, char *buffer, size_t size); 
u64 btrfs_parse_size(char *str);

int btrfs_parse_options(struct btrfs_root *root, char *options);

int btrfs_sync_fs(struct super_block *sb, int wait);



/* acl.c */

int btrfs_check_acl(struct inode *inode, int mask);

int btrfs_init_acl(struct inode *inode, struct inode *dir);

int btrfs_acl_chmod(struct inode *inode);

#endif

fs/btrfs/inode.c

+41 −1
Original line number Diff line number Diff line
@@ -36,6 +36,7 @@ 
#include <linux/bit_spinlock.h>

#include <linux/version.h>

#include <linux/xattr.h>

#include <linux/posix_acl.h>

#include "ctree.h"

#include "disk-io.h"

#include "transaction.h"
@@ -1478,6 +1479,9 @@ static int btrfs_setattr(struct dentry *dentry, struct iattr *attr) 
	}

out:

	err = inode_setattr(inode, attr);



	if (!err && ((attr->ia_valid & ATTR_MODE)))

		err = btrfs_acl_chmod(inode);

fail:

	return err;

}
@@ -2184,6 +2188,12 @@ static int btrfs_mknod(struct inode *dir, struct dentry *dentry, 
	if (IS_ERR(inode))

		goto out_unlock;



	err = btrfs_init_acl(inode, dir);

	if (err) {

		drop_inode = 1;

		goto out_unlock;

	}



	btrfs_set_trans_block_group(trans, inode);

	err = btrfs_add_nondir(trans, dentry, inode, 0);

	if (err)
@@ -2239,6 +2249,12 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry, 
	if (IS_ERR(inode))

		goto out_unlock;



	err = btrfs_init_acl(inode, dir);

	if (err) {

		drop_inode = 1;

		goto out_unlock;

	}



	btrfs_set_trans_block_group(trans, inode);

	err = btrfs_add_nondir(trans, dentry, inode, 0);

	if (err)
@@ -2366,6 +2382,11 @@ static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) 
	}



	drop_on_err = 1;



	err = btrfs_init_acl(inode, dir);

	if (err)

		goto out_fail;



	inode->i_op = &btrfs_dir_inode_operations;

	inode->i_fop = &btrfs_dir_file_operations;

	btrfs_set_trans_block_group(trans, inode);
@@ -3023,6 +3044,8 @@ struct inode *btrfs_alloc_inode(struct super_block *sb) 
		return NULL;

	ei->last_trans = 0;

	btrfs_ordered_inode_tree_init(&ei->ordered_tree);

	ei->i_acl = BTRFS_ACL_NOT_CACHED;

	ei->i_default_acl = BTRFS_ACL_NOT_CACHED;

	return &ei->vfs_inode;

}
@@ -3032,6 +3055,13 @@ void btrfs_destroy_inode(struct inode *inode) 
	WARN_ON(!list_empty(&inode->i_dentry));

	WARN_ON(inode->i_data.nrpages);



	if (BTRFS_I(inode)->i_acl &&

	    BTRFS_I(inode)->i_acl != BTRFS_ACL_NOT_CACHED)

		posix_acl_release(BTRFS_I(inode)->i_acl);

	if (BTRFS_I(inode)->i_default_acl &&

	    BTRFS_I(inode)->i_default_acl != BTRFS_ACL_NOT_CACHED)

		posix_acl_release(BTRFS_I(inode)->i_default_acl);



	while(1) {

		ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1);

		if (!ordered)
@@ -3230,6 +3260,12 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry, 
	if (IS_ERR(inode))

		goto out_unlock;



	err = btrfs_init_acl(inode, dir);

	if (err) {

		drop_inode = 1;

		goto out_unlock;

	}



	btrfs_set_trans_block_group(trans, inode);

	err = btrfs_add_nondir(trans, dentry, inode, 0);

	if (err)
@@ -3310,7 +3346,7 @@ static int btrfs_permission(struct inode *inode, int mask, 
{

	if (btrfs_test_flag(inode, READONLY) && (mask & MAY_WRITE))

		return -EACCES;

	return generic_permission(inode, mask, NULL);

	return generic_permission(inode, mask, btrfs_check_acl);

}



static struct inode_operations btrfs_dir_inode_operations = {
@@ -3392,6 +3428,10 @@ static struct inode_operations btrfs_special_inode_operations = { 
	.getattr	= btrfs_getattr,

	.setattr	= btrfs_setattr,

	.permission	= btrfs_permission,

	.setxattr	= generic_setxattr,

	.getxattr	= generic_getxattr,

	.listxattr	= btrfs_listxattr,

	.removexattr	= generic_removexattr,

};

static struct inode_operations btrfs_symlink_inode_operations = {

	.readlink	= generic_readlink,

fs/btrfs/super.c

+7 −2
Original line number Diff line number Diff line
@@ -68,7 +68,7 @@ static void btrfs_put_super (struct super_block * sb) 
enum {

	Opt_degraded, Opt_subvol, Opt_device, Opt_nodatasum, Opt_nodatacow,

	Opt_max_extent, Opt_max_inline, Opt_alloc_start, Opt_nobarrier,

	Opt_ssd, Opt_thread_pool, Opt_err,

	Opt_ssd, Opt_thread_pool, Opt_noacl,  Opt_err,

};



static match_table_t tokens = {
@@ -83,7 +83,8 @@ static match_table_t tokens = { 
	{Opt_alloc_start, "alloc_start=%s"},

	{Opt_thread_pool, "thread_pool=%d"},

	{Opt_ssd, "ssd"},

	{Opt_err, NULL}

	{Opt_noacl, "noacl"},

	{Opt_err, NULL},

};



u64 btrfs_parse_size(char *str)
@@ -215,6 +216,9 @@ int btrfs_parse_options(struct btrfs_root *root, char *options) 
					info->alloc_start);

			}

			break;

		case Opt_noacl:

			root->fs_info->sb->s_flags &= ~MS_POSIXACL;

			break;

		default:

			break;

		}
@@ -301,6 +305,7 @@ static int btrfs_fill_super(struct super_block * sb, 
	sb->s_op = &btrfs_super_ops;

	sb->s_xattr = btrfs_xattr_handlers;

	sb->s_time_gran = 1;

	sb->s_flags |= MS_POSIXACL;



	tree_root = open_ctree(sb, fs_devices, (char *)data);