[linux.git] / fs / ext3 / acl.c

/*
 * linux/fs/ext3/acl.c
 *
 * Copyright (C) 2001-2003 Andreas Gruenbacher, <[email protected]>
 */

#include "ext3.h"
#include "xattr.h"
#include "acl.h"

/*
 * Convert from filesystem to in-memory representation.
 */
static struct posix_acl *
ext3_acl_from_disk(const void *value, size_t size)
{
	const char *end = (char *)value + size;
	int n, count;
	struct posix_acl *acl;

	if (!value)
		return NULL;
	if (size < sizeof(ext3_acl_header))
		 return ERR_PTR(-EINVAL);
	if (((ext3_acl_header *)value)->a_version !=
	    cpu_to_le32(EXT3_ACL_VERSION))
		return ERR_PTR(-EINVAL);
	value = (char *)value + sizeof(ext3_acl_header);
	count = ext3_acl_count(size);
	if (count < 0)
		return ERR_PTR(-EINVAL);
	if (count == 0)
		return NULL;
	acl = posix_acl_alloc(count, GFP_NOFS);
	if (!acl)
		return ERR_PTR(-ENOMEM);
	for (n=0; n < count; n++) {
		ext3_acl_entry *entry =
			(ext3_acl_entry *)value;
		if ((char *)value + sizeof(ext3_acl_entry_short) > end)
			goto fail;
		acl->a_entries[n].e_tag  = le16_to_cpu(entry->e_tag);
		acl->a_entries[n].e_perm = le16_to_cpu(entry->e_perm);
		switch(acl->a_entries[n].e_tag) {
			case ACL_USER_OBJ:
			case ACL_GROUP_OBJ:
			case ACL_MASK:
			case ACL_OTHER:
				value = (char *)value +
					sizeof(ext3_acl_entry_short);
				acl->a_entries[n].e_id = ACL_UNDEFINED_ID;
				break;

			case ACL_USER:
			case ACL_GROUP:
				value = (char *)value + sizeof(ext3_acl_entry);
				if ((char *)value > end)
					goto fail;
				acl->a_entries[n].e_id =
					le32_to_cpu(entry->e_id);
				break;

			default:
				goto fail;
		}
	}
	if (value != end)
		goto fail;
	return acl;

fail:
	posix_acl_release(acl);
	return ERR_PTR(-EINVAL);
}

/*
 * Convert from in-memory to filesystem representation.
 */
static void *
ext3_acl_to_disk(const struct posix_acl *acl, size_t *size)
{
	ext3_acl_header *ext_acl;
	char *e;
	size_t n;

	*size = ext3_acl_size(acl->a_count);
	ext_acl = kmalloc(sizeof(ext3_acl_header) + acl->a_count *
			sizeof(ext3_acl_entry), GFP_NOFS);
	if (!ext_acl)
		return ERR_PTR(-ENOMEM);
	ext_acl->a_version = cpu_to_le32(EXT3_ACL_VERSION);
	e = (char *)ext_acl + sizeof(ext3_acl_header);
	for (n=0; n < acl->a_count; n++) {
		ext3_acl_entry *entry = (ext3_acl_entry *)e;
		entry->e_tag  = cpu_to_le16(acl->a_entries[n].e_tag);
		entry->e_perm = cpu_to_le16(acl->a_entries[n].e_perm);
		switch(acl->a_entries[n].e_tag) {
			case ACL_USER:
			case ACL_GROUP:
				entry->e_id =
					cpu_to_le32(acl->a_entries[n].e_id);
				e += sizeof(ext3_acl_entry);
				break;

			case ACL_USER_OBJ:
			case ACL_GROUP_OBJ:
			case ACL_MASK:
			case ACL_OTHER:
				e += sizeof(ext3_acl_entry_short);
				break;

			default:
				goto fail;
		}
	}
	return (char *)ext_acl;

fail:
	kfree(ext_acl);
	return ERR_PTR(-EINVAL);
}

/*
 * Inode operation get_posix_acl().
 *
 * inode->i_mutex: don't care
 */
struct posix_acl *
ext3_get_acl(struct inode *inode, int type)
{
	int name_index;
	char *value = NULL;
	struct posix_acl *acl;
	int retval;

	if (!test_opt(inode->i_sb, POSIX_ACL))
		return NULL;

	acl = get_cached_acl(inode, type);
	if (acl != ACL_NOT_CACHED)
		return acl;

	switch (type) {
	case ACL_TYPE_ACCESS:
		name_index = EXT3_XATTR_INDEX_POSIX_ACL_ACCESS;
		break;
	case ACL_TYPE_DEFAULT:
		name_index = EXT3_XATTR_INDEX_POSIX_ACL_DEFAULT;
		break;
	default:
		BUG();
	}

	retval = ext3_xattr_get(inode, name_index, "", NULL, 0);
	if (retval > 0) {
		value = kmalloc(retval, GFP_NOFS);
		if (!value)
			return ERR_PTR(-ENOMEM);
		retval = ext3_xattr_get(inode, name_index, "", value, retval);
	}
	if (retval > 0)
		acl = ext3_acl_from_disk(value, retval);
	else if (retval == -ENODATA || retval == -ENOSYS)
		acl = NULL;
	else
		acl = ERR_PTR(retval);
	kfree(value);

	if (!IS_ERR(acl))
		set_cached_acl(inode, type, acl);

	return acl;
}

/*
 * Set the access or default ACL of an inode.
 *
 * inode->i_mutex: down unless called from ext3_new_inode
 */
static int
ext3_set_acl(handle_t *handle, struct inode *inode, int type,
	     struct posix_acl *acl)
{
	int name_index;
	void *value = NULL;
	size_t size = 0;
	int error;

	if (S_ISLNK(inode->i_mode))
		return -EOPNOTSUPP;

	switch(type) {
		case ACL_TYPE_ACCESS:
			name_index = EXT3_XATTR_INDEX_POSIX_ACL_ACCESS;
			if (acl) {
				error = posix_acl_equiv_mode(acl, &inode->i_mode);
				if (error < 0)
					return error;
				else {
					inode->i_ctime = CURRENT_TIME_SEC;
					ext3_mark_inode_dirty(handle, inode);
					if (error == 0)
						acl = NULL;
				}
			}
			break;

		case ACL_TYPE_DEFAULT:
			name_index = EXT3_XATTR_INDEX_POSIX_ACL_DEFAULT;
			if (!S_ISDIR(inode->i_mode))
				return acl ? -EACCES : 0;
			break;

		default:
			return -EINVAL;
	}
	if (acl) {
		value = ext3_acl_to_disk(acl, &size);
		if (IS_ERR(value))
			return (int)PTR_ERR(value);
	}

	error = ext3_xattr_set_handle(handle, inode, name_index, "",
				      value, size, 0);

	kfree(value);

	if (!error)
		set_cached_acl(inode, type, acl);

	return error;
}

/*
 * Initialize the ACLs of a new inode. Called from ext3_new_inode.
 *
 * dir->i_mutex: down
 * inode->i_mutex: up (access to inode is still exclusive)
 */
int
ext3_init_acl(handle_t *handle, struct inode *inode, struct inode *dir)
{
	struct posix_acl *acl = NULL;
	int error = 0;

	if (!S_ISLNK(inode->i_mode)) {
		if (test_opt(dir->i_sb, POSIX_ACL)) {
			acl = ext3_get_acl(dir, ACL_TYPE_DEFAULT);
			if (IS_ERR(acl))
				return PTR_ERR(acl);
		}
		if (!acl)
			inode->i_mode &= ~current_umask();
	}
	if (test_opt(inode->i_sb, POSIX_ACL) && acl) {
		if (S_ISDIR(inode->i_mode)) {
			error = ext3_set_acl(handle, inode,
					     ACL_TYPE_DEFAULT, acl);
			if (error)
				goto cleanup;
		}
		error = posix_acl_create(&acl, GFP_NOFS, &inode->i_mode);
		if (error < 0)
			return error;

		if (error > 0) {
			/* This is an extended ACL */
			error = ext3_set_acl(handle, inode, ACL_TYPE_ACCESS, acl);
		}
	}
cleanup:
	posix_acl_release(acl);
	return error;
}

/*
 * Does chmod for an inode that may have an Access Control List. The
 * inode->i_mode field must be updated to the desired value by the caller
 * before calling this function.
 * Returns 0 on success, or a negative error number.
 *
 * We change the ACL rather than storing some ACL entries in the file
 * mode permission bits (which would be more efficient), because that
 * would break once additional permissions (like  ACL_APPEND, ACL_DELETE
 * for directories) are added. There are no more bits available in the
 * file mode.
 *
 * inode->i_mutex: down
 */
int
ext3_acl_chmod(struct inode *inode)
{
	struct posix_acl *acl;
	handle_t *handle;
	int retries = 0;
        int error;

	if (S_ISLNK(inode->i_mode))
		return -EOPNOTSUPP;
	if (!test_opt(inode->i_sb, POSIX_ACL))
		return 0;
	acl = ext3_get_acl(inode, ACL_TYPE_ACCESS);
	if (IS_ERR(acl) || !acl)
		return PTR_ERR(acl);
	error = posix_acl_chmod(&acl, GFP_KERNEL, inode->i_mode);
	if (error)
		return error;
retry:
	handle = ext3_journal_start(inode,
			EXT3_DATA_TRANS_BLOCKS(inode->i_sb));
	if (IS_ERR(handle)) {
		error = PTR_ERR(handle);
		ext3_std_error(inode->i_sb, error);
		goto out;
	}
	error = ext3_set_acl(handle, inode, ACL_TYPE_ACCESS, acl);
	ext3_journal_stop(handle);
	if (error == -ENOSPC &&
	    ext3_should_retry_alloc(inode->i_sb, &retries))
		goto retry;
out:
	posix_acl_release(acl);
	return error;
}

/*
 * Extended attribute handlers
 */
static size_t
ext3_xattr_list_acl_access(struct dentry *dentry, char *list, size_t list_len,
			   const char *name, size_t name_len, int type)
{
	const size_t size = sizeof(POSIX_ACL_XATTR_ACCESS);

	if (!test_opt(dentry->d_sb, POSIX_ACL))
		return 0;
	if (list && size <= list_len)
		memcpy(list, POSIX_ACL_XATTR_ACCESS, size);
	return size;
}

static size_t
ext3_xattr_list_acl_default(struct dentry *dentry, char *list, size_t list_len,
			    const char *name, size_t name_len, int type)
{
	const size_t size = sizeof(POSIX_ACL_XATTR_DEFAULT);

	if (!test_opt(dentry->d_sb, POSIX_ACL))
		return 0;
	if (list && size <= list_len)
		memcpy(list, POSIX_ACL_XATTR_DEFAULT, size);
	return size;
}

static int
ext3_xattr_get_acl(struct dentry *dentry, const char *name, void *buffer,
		   size_t size, int type)
{
	struct posix_acl *acl;
	int error;

	if (strcmp(name, "") != 0)
		return -EINVAL;
	if (!test_opt(dentry->d_sb, POSIX_ACL))
		return -EOPNOTSUPP;

	acl = ext3_get_acl(dentry->d_inode, type);
	if (IS_ERR(acl))
		return PTR_ERR(acl);
	if (acl == NULL)
		return -ENODATA;
	error = posix_acl_to_xattr(acl, buffer, size);
	posix_acl_release(acl);

	return error;
}

static int
ext3_xattr_set_acl(struct dentry *dentry, const char *name, const void *value,
		   size_t size, int flags, int type)
{
	struct inode *inode = dentry->d_inode;
	handle_t *handle;
	struct posix_acl *acl;
	int error, retries = 0;

	if (strcmp(name, "") != 0)
		return -EINVAL;
	if (!test_opt(inode->i_sb, POSIX_ACL))
		return -EOPNOTSUPP;
	if (!inode_owner_or_capable(inode))
		return -EPERM;

	if (value) {
		acl = posix_acl_from_xattr(value, size);
		if (IS_ERR(acl))
			return PTR_ERR(acl);
		else if (acl) {
			error = posix_acl_valid(acl);
			if (error)
				goto release_and_out;
		}
	} else
		acl = NULL;

retry:
	handle = ext3_journal_start(inode, EXT3_DATA_TRANS_BLOCKS(inode->i_sb));
	if (IS_ERR(handle))
		return PTR_ERR(handle);
	error = ext3_set_acl(handle, inode, type, acl);
	ext3_journal_stop(handle);
	if (error == -ENOSPC && ext3_should_retry_alloc(inode->i_sb, &retries))
		goto retry;

release_and_out:
	posix_acl_release(acl);
	return error;
}

const struct xattr_handler ext3_xattr_acl_access_handler = {
	.prefix	= POSIX_ACL_XATTR_ACCESS,
	.flags	= ACL_TYPE_ACCESS,
	.list	= ext3_xattr_list_acl_access,
	.get	= ext3_xattr_get_acl,
	.set	= ext3_xattr_set_acl,
};

const struct xattr_handler ext3_xattr_acl_default_handler = {
	.prefix	= POSIX_ACL_XATTR_DEFAULT,
	.flags	= ACL_TYPE_DEFAULT,
	.list	= ext3_xattr_list_acl_default,
	.get	= ext3_xattr_get_acl,
	.set	= ext3_xattr_set_acl,
};
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/fs/ext3/acl.c
	3	*
	4	* Copyright (C) 2001-2003 Andreas Gruenbacher, <[email protected]>
	5	*/
	6
4613ad18	7	#include "ext3.h"
1da177e4 LT	8	#include "xattr.h"
	9	#include "acl.h"
	10
	11	/*
	12	* Convert from filesystem to in-memory representation.
	13	*/
	14	static struct posix_acl *
	15	ext3_acl_from_disk(const void *value, size_t size)
	16	{
	17	const char end = (char )value + size;
	18	int n, count;
	19	struct posix_acl *acl;
	20
	21	if (!value)
	22	return NULL;
	23	if (size < sizeof(ext3_acl_header))
	24	return ERR_PTR(-EINVAL);
	25	if (((ext3_acl_header *)value)->a_version !=
	26	cpu_to_le32(EXT3_ACL_VERSION))
	27	return ERR_PTR(-EINVAL);
	28	value = (char *)value + sizeof(ext3_acl_header);
	29	count = ext3_acl_count(size);
	30	if (count < 0)
	31	return ERR_PTR(-EINVAL);
	32	if (count == 0)
	33	return NULL;
c587f0c0	34	acl = posix_acl_alloc(count, GFP_NOFS);
1da177e4 LT	35	if (!acl)
	36	return ERR_PTR(-ENOMEM);
	37	for (n=0; n < count; n++) {
	38	ext3_acl_entry *entry =
	39	(ext3_acl_entry *)value;
	40	if ((char *)value + sizeof(ext3_acl_entry_short) > end)
	41	goto fail;
	42	acl->a_entries[n].e_tag = le16_to_cpu(entry->e_tag);
	43	acl->a_entries[n].e_perm = le16_to_cpu(entry->e_perm);
	44	switch(acl->a_entries[n].e_tag) {
	45	case ACL_USER_OBJ:
	46	case ACL_GROUP_OBJ:
	47	case ACL_MASK:
	48	case ACL_OTHER:
	49	value = (char *)value +
	50	sizeof(ext3_acl_entry_short);
	51	acl->a_entries[n].e_id = ACL_UNDEFINED_ID;
	52	break;
	53
	54	case ACL_USER:
	55	case ACL_GROUP:
	56	value = (char *)value + sizeof(ext3_acl_entry);
	57	if ((char *)value > end)
	58	goto fail;
	59	acl->a_entries[n].e_id =
	60	le32_to_cpu(entry->e_id);
	61	break;
	62
	63	default:
	64	goto fail;
	65	}
	66	}
	67	if (value != end)
	68	goto fail;
	69	return acl;
	70
	71	fail:
	72	posix_acl_release(acl);
	73	return ERR_PTR(-EINVAL);
	74	}
	75
	76	/*
	77	* Convert from in-memory to filesystem representation.
	78	*/
	79	static void *
	80	ext3_acl_to_disk(const struct posix_acl acl, size_t size)
	81	{
	82	ext3_acl_header *ext_acl;
	83	char *e;
	84	size_t n;
	85
	86	*size = ext3_acl_size(acl->a_count);
f52720ca	87	ext_acl = kmalloc(sizeof(ext3_acl_header) + acl->a_count *
c587f0c0	88	sizeof(ext3_acl_entry), GFP_NOFS);
1da177e4 LT	89	if (!ext_acl)
	90	return ERR_PTR(-ENOMEM);
	91	ext_acl->a_version = cpu_to_le32(EXT3_ACL_VERSION);
	92	e = (char *)ext_acl + sizeof(ext3_acl_header);
	93	for (n=0; n < acl->a_count; n++) {
	94	ext3_acl_entry entry = (ext3_acl_entry )e;
	95	entry->e_tag = cpu_to_le16(acl->a_entries[n].e_tag);
	96	entry->e_perm = cpu_to_le16(acl->a_entries[n].e_perm);
	97	switch(acl->a_entries[n].e_tag) {
	98	case ACL_USER:
	99	case ACL_GROUP:
	100	entry->e_id =
	101	cpu_to_le32(acl->a_entries[n].e_id);
	102	e += sizeof(ext3_acl_entry);
	103	break;
	104
	105	case ACL_USER_OBJ:
	106	case ACL_GROUP_OBJ:
	107	case ACL_MASK:
	108	case ACL_OTHER:
	109	e += sizeof(ext3_acl_entry_short);
	110	break;
	111
	112	default:
	113	goto fail;
	114	}
	115	}
	116	return (char *)ext_acl;
	117
	118	fail:
	119	kfree(ext_acl);
	120	return ERR_PTR(-EINVAL);
	121	}
	122
1da177e4 LT	123	/*
	124	* Inode operation get_posix_acl().
	125	*
1b1dcc1b	126	* inode->i_mutex: don't care
1da177e4	127	*/
4e34e719	128	struct posix_acl *
1da177e4 LT	129	ext3_get_acl(struct inode *inode, int type)
1da177e4 LT	130	{
1da177e4 LT	131	int name_index;
	132	char *value = NULL;
	133	struct posix_acl *acl;
	134	int retval;
	135
	136	if (!test_opt(inode->i_sb, POSIX_ACL))
	137	return NULL;
	138
073aaa1b AV	139	acl = get_cached_acl(inode, type);
	140	if (acl != ACL_NOT_CACHED)
	141	return acl;
	142
	143	switch (type) {
	144	case ACL_TYPE_ACCESS:
	145	name_index = EXT3_XATTR_INDEX_POSIX_ACL_ACCESS;
	146	break;
	147	case ACL_TYPE_DEFAULT:
	148	name_index = EXT3_XATTR_INDEX_POSIX_ACL_DEFAULT;
	149	break;
	150	default:
	151	BUG();
1da177e4	152	}
073aaa1b	153
1da177e4 LT	154	retval = ext3_xattr_get(inode, name_index, "", NULL, 0);
1da177e4 LT	155	if (retval > 0) {
c587f0c0	156	value = kmalloc(retval, GFP_NOFS);
1da177e4 LT	157	if (!value)
	158	return ERR_PTR(-ENOMEM);
	159	retval = ext3_xattr_get(inode, name_index, "", value, retval);
	160	}
	161	if (retval > 0)
	162	acl = ext3_acl_from_disk(value, retval);
	163	else if (retval == -ENODATA \|\| retval == -ENOSYS)
	164	acl = NULL;
	165	else
	166	acl = ERR_PTR(retval);
	167	kfree(value);
	168
073aaa1b AV	169	if (!IS_ERR(acl))
073aaa1b AV	170	set_cached_acl(inode, type, acl);
1da177e4	171
1da177e4 LT	172	return acl;
	173	}
	174
	175	/*
	176	* Set the access or default ACL of an inode.
	177	*
1b1dcc1b	178	* inode->i_mutex: down unless called from ext3_new_inode
1da177e4 LT	179	*/
	180	static int
	181	ext3_set_acl(handle_t handle, struct inode inode, int type,
	182	struct posix_acl *acl)
	183	{
1da177e4 LT	184	int name_index;
1da177e4 LT	185	void *value = NULL;
dfa08592	186	size_t size = 0;
1da177e4 LT	187	int error;
	188
	189	if (S_ISLNK(inode->i_mode))
	190	return -EOPNOTSUPP;
	191
	192	switch(type) {
	193	case ACL_TYPE_ACCESS:
	194	name_index = EXT3_XATTR_INDEX_POSIX_ACL_ACCESS;
	195	if (acl) {
d6952123	196	error = posix_acl_equiv_mode(acl, &inode->i_mode);
1da177e4 LT	197	if (error < 0)
	198	return error;
	199	else {
30e2bab2	200	inode->i_ctime = CURRENT_TIME_SEC;
1da177e4 LT	201	ext3_mark_inode_dirty(handle, inode);
	202	if (error == 0)
	203	acl = NULL;
	204	}
	205	}
	206	break;
	207
	208	case ACL_TYPE_DEFAULT:
	209	name_index = EXT3_XATTR_INDEX_POSIX_ACL_DEFAULT;
	210	if (!S_ISDIR(inode->i_mode))
	211	return acl ? -EACCES : 0;
	212	break;
	213
	214	default:
	215	return -EINVAL;
	216	}
e9ad5620	217	if (acl) {
1da177e4 LT	218	value = ext3_acl_to_disk(acl, &size);
	219	if (IS_ERR(value))
	220	return (int)PTR_ERR(value);
	221	}
	222
	223	error = ext3_xattr_set_handle(handle, inode, name_index, "",
	224	value, size, 0);
	225
	226	kfree(value);
1da177e4	227
073aaa1b AV	228	if (!error)
	229	set_cached_acl(inode, type, acl);
	230
1da177e4 LT	231	return error;
	232	}
	233
1da177e4 LT	234	/*
	235	* Initialize the ACLs of a new inode. Called from ext3_new_inode.
	236	*
1b1dcc1b JS	237	* dir->i_mutex: down
1b1dcc1b JS	238	* inode->i_mutex: up (access to inode is still exclusive)
1da177e4 LT	239	*/
	240	int
	241	ext3_init_acl(handle_t handle, struct inode inode, struct inode *dir)
	242	{
	243	struct posix_acl *acl = NULL;
	244	int error = 0;
	245
	246	if (!S_ISLNK(inode->i_mode)) {
	247	if (test_opt(dir->i_sb, POSIX_ACL)) {
	248	acl = ext3_get_acl(dir, ACL_TYPE_DEFAULT);
	249	if (IS_ERR(acl))
	250	return PTR_ERR(acl);
	251	}
	252	if (!acl)
ce3b0f8d	253	inode->i_mode &= ~current_umask();
1da177e4 LT	254	}
1da177e4 LT	255	if (test_opt(inode->i_sb, POSIX_ACL) && acl) {
1da177e4 LT	256	if (S_ISDIR(inode->i_mode)) {
	257	error = ext3_set_acl(handle, inode,
	258	ACL_TYPE_DEFAULT, acl);
	259	if (error)
	260	goto cleanup;
	261	}
d3fb6120	262	error = posix_acl_create(&acl, GFP_NOFS, &inode->i_mode);
826cae2f AV	263	if (error < 0)
	264	return error;
	265
826cae2f AV	266	if (error > 0) {
	267	/* This is an extended ACL */
	268	error = ext3_set_acl(handle, inode, ACL_TYPE_ACCESS, acl);
1da177e4	269	}
1da177e4 LT	270	}
	271	cleanup:
	272	posix_acl_release(acl);
	273	return error;
	274	}
	275
	276	/*
	277	* Does chmod for an inode that may have an Access Control List. The
	278	* inode->i_mode field must be updated to the desired value by the caller
	279	* before calling this function.
	280	* Returns 0 on success, or a negative error number.
	281	*
	282	* We change the ACL rather than storing some ACL entries in the file
	283	* mode permission bits (which would be more efficient), because that
	284	* would break once additional permissions (like ACL_APPEND, ACL_DELETE
	285	* for directories) are added. There are no more bits available in the
	286	* file mode.
	287	*
1b1dcc1b	288	* inode->i_mutex: down
1da177e4 LT	289	*/
	290	int
	291	ext3_acl_chmod(struct inode *inode)
	292	{
bc26ab5f AV	293	struct posix_acl *acl;
	294	handle_t *handle;
	295	int retries = 0;
1da177e4 LT	296	int error;
	297
	298	if (S_ISLNK(inode->i_mode))
	299	return -EOPNOTSUPP;
	300	if (!test_opt(inode->i_sb, POSIX_ACL))
	301	return 0;
	302	acl = ext3_get_acl(inode, ACL_TYPE_ACCESS);
	303	if (IS_ERR(acl) \|\| !acl)
	304	return PTR_ERR(acl);
bc26ab5f AV	305	error = posix_acl_chmod(&acl, GFP_KERNEL, inode->i_mode);
	306	if (error)
	307	return error;
	308	retry:
	309	handle = ext3_journal_start(inode,
	310	EXT3_DATA_TRANS_BLOCKS(inode->i_sb));
	311	if (IS_ERR(handle)) {
	312	error = PTR_ERR(handle);
	313	ext3_std_error(inode->i_sb, error);
	314	goto out;
1da177e4	315	}
bc26ab5f AV	316	error = ext3_set_acl(handle, inode, ACL_TYPE_ACCESS, acl);
	317	ext3_journal_stop(handle);
	318	if (error == -ENOSPC &&
	319	ext3_should_retry_alloc(inode->i_sb, &retries))
	320	goto retry;
1da177e4	321	out:
bc26ab5f	322	posix_acl_release(acl);
1da177e4 LT	323	return error;
	324	}
	325
	326	/*
	327	* Extended attribute handlers
	328	*/
	329	static size_t
431547b3 CH	330	ext3_xattr_list_acl_access(struct dentry dentry, char list, size_t list_len,
431547b3 CH	331	const char *name, size_t name_len, int type)
1da177e4	332	{
9a59f452	333	const size_t size = sizeof(POSIX_ACL_XATTR_ACCESS);
1da177e4	334
431547b3	335	if (!test_opt(dentry->d_sb, POSIX_ACL))
1da177e4 LT	336	return 0;
1da177e4 LT	337	if (list && size <= list_len)
9a59f452	338	memcpy(list, POSIX_ACL_XATTR_ACCESS, size);
1da177e4 LT	339	return size;
	340	}
	341
	342	static size_t
431547b3 CH	343	ext3_xattr_list_acl_default(struct dentry dentry, char list, size_t list_len,
431547b3 CH	344	const char *name, size_t name_len, int type)
1da177e4	345	{
9a59f452	346	const size_t size = sizeof(POSIX_ACL_XATTR_DEFAULT);
1da177e4	347
431547b3	348	if (!test_opt(dentry->d_sb, POSIX_ACL))
1da177e4 LT	349	return 0;
1da177e4 LT	350	if (list && size <= list_len)
9a59f452	351	memcpy(list, POSIX_ACL_XATTR_DEFAULT, size);
1da177e4 LT	352	return size;
	353	}
	354
	355	static int
431547b3 CH	356	ext3_xattr_get_acl(struct dentry dentry, const char name, void *buffer,
431547b3 CH	357	size_t size, int type)
1da177e4 LT	358	{
	359	struct posix_acl *acl;
	360	int error;
	361
431547b3 CH	362	if (strcmp(name, "") != 0)
	363	return -EINVAL;
	364	if (!test_opt(dentry->d_sb, POSIX_ACL))
1da177e4 LT	365	return -EOPNOTSUPP;
1da177e4 LT	366
431547b3	367	acl = ext3_get_acl(dentry->d_inode, type);
1da177e4 LT	368	if (IS_ERR(acl))
	369	return PTR_ERR(acl);
	370	if (acl == NULL)
	371	return -ENODATA;
	372	error = posix_acl_to_xattr(acl, buffer, size);
	373	posix_acl_release(acl);
	374
	375	return error;
	376	}
	377
	378	static int
431547b3 CH	379	ext3_xattr_set_acl(struct dentry dentry, const char name, const void *value,
431547b3 CH	380	size_t size, int flags, int type)
1da177e4	381	{
431547b3	382	struct inode *inode = dentry->d_inode;
1da177e4 LT	383	handle_t *handle;
	384	struct posix_acl *acl;
	385	int error, retries = 0;
	386
431547b3 CH	387	if (strcmp(name, "") != 0)
431547b3 CH	388	return -EINVAL;
1da177e4 LT	389	if (!test_opt(inode->i_sb, POSIX_ACL))
1da177e4 LT	390	return -EOPNOTSUPP;
2e149670	391	if (!inode_owner_or_capable(inode))
1da177e4 LT	392	return -EPERM;
	393
	394	if (value) {
	395	acl = posix_acl_from_xattr(value, size);
	396	if (IS_ERR(acl))
	397	return PTR_ERR(acl);
	398	else if (acl) {
	399	error = posix_acl_valid(acl);
	400	if (error)
	401	goto release_and_out;
	402	}
	403	} else
	404	acl = NULL;
	405
	406	retry:
1f54587b	407	handle = ext3_journal_start(inode, EXT3_DATA_TRANS_BLOCKS(inode->i_sb));
1da177e4 LT	408	if (IS_ERR(handle))
	409	return PTR_ERR(handle);
	410	error = ext3_set_acl(handle, inode, type, acl);
	411	ext3_journal_stop(handle);
	412	if (error == -ENOSPC && ext3_should_retry_alloc(inode->i_sb, &retries))
	413	goto retry;
	414
	415	release_and_out:
	416	posix_acl_release(acl);
	417	return error;
	418	}
	419
d1f21049	420	const struct xattr_handler ext3_xattr_acl_access_handler = {
9a59f452	421	.prefix = POSIX_ACL_XATTR_ACCESS,
431547b3	422	.flags = ACL_TYPE_ACCESS,
1da177e4	423	.list = ext3_xattr_list_acl_access,
431547b3 CH	424	.get = ext3_xattr_get_acl,
431547b3 CH	425	.set = ext3_xattr_set_acl,
1da177e4 LT	426	};
1da177e4 LT	427
d1f21049	428	const struct xattr_handler ext3_xattr_acl_default_handler = {
9a59f452	429	.prefix = POSIX_ACL_XATTR_DEFAULT,
431547b3	430	.flags = ACL_TYPE_DEFAULT,
1da177e4	431	.list = ext3_xattr_list_acl_default,
431547b3 CH	432	.get = ext3_xattr_get_acl,
431547b3 CH	433	.set = ext3_xattr_set_acl,
1da177e4	434	};