[mirror_ubuntu-artful-kernel.git] / fs / reiserfs / xattr_acl.c

#include <linux/capability.h>
#include <linux/fs.h>
#include <linux/posix_acl.h>
#include <linux/reiserfs_fs.h>
#include <linux/errno.h>
#include <linux/pagemap.h>
#include <linux/xattr.h>
#include <linux/posix_acl_xattr.h>
#include <linux/reiserfs_xattr.h>
#include <linux/reiserfs_acl.h>
#include <asm/uaccess.h>

static int reiserfs_set_acl(struct inode *inode, int type,
			    struct posix_acl *acl);

static int
xattr_set_acl(struct inode *inode, int type, const void *value, size_t size)
{
	struct posix_acl *acl;
	int error;

	if (!reiserfs_posixacl(inode->i_sb))
		return -EOPNOTSUPP;
	if (!is_owner_or_cap(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;

	error = reiserfs_set_acl(inode, type, acl);

      release_and_out:
	posix_acl_release(acl);
	return error;
}

static int
xattr_get_acl(struct inode *inode, int type, void *buffer, size_t size)
{
	struct posix_acl *acl;
	int error;

	if (!reiserfs_posixacl(inode->i_sb))
		return -EOPNOTSUPP;

	acl = reiserfs_get_acl(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;
}

/*
 * Convert from filesystem to in-memory representation.
 */
static struct posix_acl *posix_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(reiserfs_acl_header))
		return ERR_PTR(-EINVAL);
	if (((reiserfs_acl_header *) value)->a_version !=
	    cpu_to_le32(REISERFS_ACL_VERSION))
		return ERR_PTR(-EINVAL);
	value = (char *)value + sizeof(reiserfs_acl_header);
	count = reiserfs_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++) {
		reiserfs_acl_entry *entry = (reiserfs_acl_entry *) value;
		if ((char *)value + sizeof(reiserfs_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(reiserfs_acl_entry_short);
			acl->a_entries[n].e_id = ACL_UNDEFINED_ID;
			break;

		case ACL_USER:
		case ACL_GROUP:
			value = (char *)value + sizeof(reiserfs_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 *posix_acl_to_disk(const struct posix_acl *acl, size_t * size)
{
	reiserfs_acl_header *ext_acl;
	char *e;
	int n;

	*size = reiserfs_acl_size(acl->a_count);
	ext_acl = kmalloc(sizeof(reiserfs_acl_header) +
						  acl->a_count *
						  sizeof(reiserfs_acl_entry),
						  GFP_NOFS);
	if (!ext_acl)
		return ERR_PTR(-ENOMEM);
	ext_acl->a_version = cpu_to_le32(REISERFS_ACL_VERSION);
	e = (char *)ext_acl + sizeof(reiserfs_acl_header);
	for (n = 0; n < acl->a_count; n++) {
		reiserfs_acl_entry *entry = (reiserfs_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(reiserfs_acl_entry);
			break;

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

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

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

static inline void iset_acl(struct inode *inode, struct posix_acl **i_acl,
			    struct posix_acl *acl)
{
	spin_lock(&inode->i_lock);
	if (*i_acl != ERR_PTR(-ENODATA))
		posix_acl_release(*i_acl);
	*i_acl = posix_acl_dup(acl);
	spin_unlock(&inode->i_lock);
}

static inline struct posix_acl *iget_acl(struct inode *inode,
					 struct posix_acl **i_acl)
{
	struct posix_acl *acl = ERR_PTR(-ENODATA);

	spin_lock(&inode->i_lock);
	if (*i_acl != ERR_PTR(-ENODATA))
		acl = posix_acl_dup(*i_acl);
	spin_unlock(&inode->i_lock);

	return acl;
}

/*
 * Inode operation get_posix_acl().
 *
 * inode->i_mutex: down
 * BKL held [before 2.5.x]
 */
struct posix_acl *reiserfs_get_acl(struct inode *inode, int type)
{
	char *name, *value;
	struct posix_acl *acl, **p_acl;
	int size;
	int retval;
	struct reiserfs_inode_info *reiserfs_i = REISERFS_I(inode);

	switch (type) {
	case ACL_TYPE_ACCESS:
		name = POSIX_ACL_XATTR_ACCESS;
		p_acl = &reiserfs_i->i_acl_access;
		break;
	case ACL_TYPE_DEFAULT:
		name = POSIX_ACL_XATTR_DEFAULT;
		p_acl = &reiserfs_i->i_acl_default;
		break;
	default:
		return ERR_PTR(-EINVAL);
	}

	acl = iget_acl(inode, p_acl);
	if (acl && !IS_ERR(acl))
		return acl;
	else if (PTR_ERR(acl) == -ENODATA)
		return NULL;

	size = reiserfs_xattr_get(inode, name, NULL, 0);
	if (size < 0) {
		if (size == -ENODATA || size == -ENOSYS) {
			*p_acl = ERR_PTR(-ENODATA);
			return NULL;
		}
		return ERR_PTR(size);
	}

	value = kmalloc(size, GFP_NOFS);
	if (!value)
		return ERR_PTR(-ENOMEM);

	retval = reiserfs_xattr_get(inode, name, value, size);
	if (retval == -ENODATA || retval == -ENOSYS) {
		/* This shouldn't actually happen as it should have
		   been caught above.. but just in case */
		acl = NULL;
		*p_acl = ERR_PTR(-ENODATA);
	} else if (retval < 0) {
		acl = ERR_PTR(retval);
	} else {
		acl = posix_acl_from_disk(value, retval);
		if (!IS_ERR(acl))
			iset_acl(inode, p_acl, acl);
	}

	kfree(value);
	return acl;
}

/*
 * Inode operation set_posix_acl().
 *
 * inode->i_mutex: down
 * BKL held [before 2.5.x]
 */
static int
reiserfs_set_acl(struct inode *inode, int type, struct posix_acl *acl)
{
	char *name;
	void *value = NULL;
	struct posix_acl **p_acl;
	size_t size = 0;
	int error;
	struct reiserfs_inode_info *reiserfs_i = REISERFS_I(inode);

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

	switch (type) {
	case ACL_TYPE_ACCESS:
		name = POSIX_ACL_XATTR_ACCESS;
		p_acl = &reiserfs_i->i_acl_access;
		if (acl) {
			mode_t mode = inode->i_mode;
			error = posix_acl_equiv_mode(acl, &mode);
			if (error < 0)
				return error;
			else {
				inode->i_mode = mode;
				if (error == 0)
					acl = NULL;
			}
		}
		break;
	case ACL_TYPE_DEFAULT:
		name = POSIX_ACL_XATTR_DEFAULT;
		p_acl = &reiserfs_i->i_acl_default;
		if (!S_ISDIR(inode->i_mode))
			return acl ? -EACCES : 0;
		break;
	default:
		return -EINVAL;
	}

	if (acl) {
		value = posix_acl_to_disk(acl, &size);
		if (IS_ERR(value))
			return (int)PTR_ERR(value);
	}

	error = __reiserfs_xattr_set(inode, name, value, size, 0);

	/*
	 * Ensure that the inode gets dirtied if we're only using
	 * the mode bits and an old ACL didn't exist. We don't need
	 * to check if the inode is hashed here since we won't get
	 * called by reiserfs_inherit_default_acl().
	 */
	if (error == -ENODATA) {
		error = 0;
		if (type == ACL_TYPE_ACCESS) {
			inode->i_ctime = CURRENT_TIME_SEC;
			mark_inode_dirty(inode);
		}
	}

	kfree(value);

	if (!error)
		iset_acl(inode, p_acl, acl);

	return error;
}

/* dir->i_mutex: locked,
 * inode is new and not released into the wild yet */
int
reiserfs_inherit_default_acl(struct inode *dir, struct dentry *dentry,
			     struct inode *inode)
{
	struct posix_acl *acl;
	int err = 0;

	/* ACLs only get applied to files and directories */
	if (S_ISLNK(inode->i_mode))
		return 0;

	/* ACLs can only be used on "new" objects, so if it's an old object
	 * there is nothing to inherit from */
	if (get_inode_sd_version(dir) == STAT_DATA_V1)
		goto apply_umask;

	/* Don't apply ACLs to objects in the .reiserfs_priv tree.. This
	 * would be useless since permissions are ignored, and a pain because
	 * it introduces locking cycles */
	if (IS_PRIVATE(dir)) {
		inode->i_flags |= S_PRIVATE;
		goto apply_umask;
	}

	acl = reiserfs_get_acl(dir, ACL_TYPE_DEFAULT);
	if (IS_ERR(acl)) {
		if (PTR_ERR(acl) == -ENODATA)
			goto apply_umask;
		return PTR_ERR(acl);
	}

	if (acl) {
		struct posix_acl *acl_copy;
		mode_t mode = inode->i_mode;
		int need_acl;

		/* Copy the default ACL to the default ACL of a new directory */
		if (S_ISDIR(inode->i_mode)) {
			err = reiserfs_set_acl(inode, ACL_TYPE_DEFAULT, acl);
			if (err)
				goto cleanup;
		}

		/* Now we reconcile the new ACL and the mode,
		   potentially modifying both */
		acl_copy = posix_acl_clone(acl, GFP_NOFS);
		if (!acl_copy) {
			err = -ENOMEM;
			goto cleanup;
		}

		need_acl = posix_acl_create_masq(acl_copy, &mode);
		if (need_acl >= 0) {
			if (mode != inode->i_mode) {
				inode->i_mode = mode;
			}

			/* If we need an ACL.. */
			if (need_acl > 0) {
				err =
				    reiserfs_set_acl(inode, ACL_TYPE_ACCESS,
						     acl_copy);
				if (err)
					goto cleanup_copy;
			}
		}
	      cleanup_copy:
		posix_acl_release(acl_copy);
	      cleanup:
		posix_acl_release(acl);
	} else {
	      apply_umask:
		/* no ACL, apply umask */
		inode->i_mode &= ~current->fs->umask;
	}

	return err;
}

/* Looks up and caches the result of the default ACL.
 * We do this so that we don't need to carry the xattr_sem into
 * reiserfs_new_inode if we don't need to */
int reiserfs_cache_default_acl(struct inode *inode)
{
	int ret = 0;
	if (reiserfs_posixacl(inode->i_sb) && !IS_PRIVATE(inode)) {
		struct posix_acl *acl;
		acl = reiserfs_get_acl(inode, ACL_TYPE_DEFAULT);
		ret = (acl && !IS_ERR(acl));
		if (ret)
			posix_acl_release(acl);
	}

	return ret;
}

int reiserfs_acl_chmod(struct inode *inode)
{
	struct posix_acl *acl, *clone;
	int error;

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

	if (get_inode_sd_version(inode) == STAT_DATA_V1 ||
	    !reiserfs_posixacl(inode->i_sb)) {
		return 0;
	}

	acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS);
	if (!acl)
		return 0;
	if (IS_ERR(acl))
		return PTR_ERR(acl);
	clone = posix_acl_clone(acl, GFP_NOFS);
	posix_acl_release(acl);
	if (!clone)
		return -ENOMEM;
	error = posix_acl_chmod_masq(clone, inode->i_mode);
	if (!error)
		error = reiserfs_set_acl(inode, ACL_TYPE_ACCESS, clone);
	posix_acl_release(clone);
	return error;
}

static int
posix_acl_access_get(struct inode *inode, const char *name,
		     void *buffer, size_t size)
{
	if (strlen(name) != sizeof(POSIX_ACL_XATTR_ACCESS) - 1)
		return -EINVAL;
	return xattr_get_acl(inode, ACL_TYPE_ACCESS, buffer, size);
}

static int
posix_acl_access_set(struct inode *inode, const char *name,
		     const void *value, size_t size, int flags)
{
	if (strlen(name) != sizeof(POSIX_ACL_XATTR_ACCESS) - 1)
		return -EINVAL;
	return xattr_set_acl(inode, ACL_TYPE_ACCESS, value, size);
}

static size_t posix_acl_access_list(struct inode *inode, char *list,
				    size_t list_size, const char *name,
				    size_t name_len)
{
	const size_t size = sizeof(POSIX_ACL_XATTR_ACCESS);
	if (!reiserfs_posixacl(inode->i_sb))
		return 0;
	if (list && size <= list_size)
		memcpy(list, POSIX_ACL_XATTR_ACCESS, size);
	return size;
}

struct xattr_handler reiserfs_posix_acl_access_handler = {
	.prefix = POSIX_ACL_XATTR_ACCESS,
	.get = posix_acl_access_get,
	.set = posix_acl_access_set,
	.list = posix_acl_access_list,
};

static int
posix_acl_default_get(struct inode *inode, const char *name,
		      void *buffer, size_t size)
{
	if (strlen(name) != sizeof(POSIX_ACL_XATTR_DEFAULT) - 1)
		return -EINVAL;
	return xattr_get_acl(inode, ACL_TYPE_DEFAULT, buffer, size);
}

static int
posix_acl_default_set(struct inode *inode, const char *name,
		      const void *value, size_t size, int flags)
{
	if (strlen(name) != sizeof(POSIX_ACL_XATTR_DEFAULT) - 1)
		return -EINVAL;
	return xattr_set_acl(inode, ACL_TYPE_DEFAULT, value, size);
}

static size_t posix_acl_default_list(struct inode *inode, char *list,
				     size_t list_size, const char *name,
				     size_t name_len)
{
	const size_t size = sizeof(POSIX_ACL_XATTR_DEFAULT);
	if (!reiserfs_posixacl(inode->i_sb))
		return 0;
	if (list && size <= list_size)
		memcpy(list, POSIX_ACL_XATTR_DEFAULT, size);
	return size;
}

struct xattr_handler reiserfs_posix_acl_default_handler = {
	.prefix = POSIX_ACL_XATTR_DEFAULT,
	.get = posix_acl_default_get,
	.set = posix_acl_default_set,
	.list = posix_acl_default_list,
};
Commit	Line	Data
	1	#include <linux/capability.h>
	2	#include <linux/fs.h>
	3	#include <linux/posix_acl.h>
	4	#include <linux/reiserfs_fs.h>
	5	#include <linux/errno.h>
	6	#include <linux/pagemap.h>
	7	#include <linux/xattr.h>
	8	#include <linux/posix_acl_xattr.h>
	9	#include <linux/reiserfs_xattr.h>
	10	#include <linux/reiserfs_acl.h>
	11	#include <asm/uaccess.h>
	12
	13	static int reiserfs_set_acl(struct inode *inode, int type,
	14	struct posix_acl *acl);
	15
	16	static int
	17	xattr_set_acl(struct inode inode, int type, const void value, size_t size)
	18	{
	19	struct posix_acl *acl;
	20	int error;
	21
	22	if (!reiserfs_posixacl(inode->i_sb))
	23	return -EOPNOTSUPP;
	24	if (!is_owner_or_cap(inode))
	25	return -EPERM;
	26
	27	if (value) {
	28	acl = posix_acl_from_xattr(value, size);
	29	if (IS_ERR(acl)) {
	30	return PTR_ERR(acl);
	31	} else if (acl) {
	32	error = posix_acl_valid(acl);
	33	if (error)
	34	goto release_and_out;
	35	}
	36	} else
	37	acl = NULL;
	38
	39	error = reiserfs_set_acl(inode, type, acl);
	40
	41	release_and_out:
	42	posix_acl_release(acl);
	43	return error;
	44	}
	45
	46	static int
	47	xattr_get_acl(struct inode inode, int type, void buffer, size_t size)
	48	{
	49	struct posix_acl *acl;
	50	int error;
	51
	52	if (!reiserfs_posixacl(inode->i_sb))
	53	return -EOPNOTSUPP;
	54
	55	acl = reiserfs_get_acl(inode, type);
	56	if (IS_ERR(acl))
	57	return PTR_ERR(acl);
	58	if (acl == NULL)
	59	return -ENODATA;
	60	error = posix_acl_to_xattr(acl, buffer, size);
	61	posix_acl_release(acl);
	62
	63	return error;
	64	}
	65
	66	/*
	67	* Convert from filesystem to in-memory representation.
	68	*/
	69	static struct posix_acl posix_acl_from_disk(const void value, size_t size)
	70	{
	71	const char end = (char )value + size;
	72	int n, count;
	73	struct posix_acl *acl;
	74
	75	if (!value)
	76	return NULL;
	77	if (size < sizeof(reiserfs_acl_header))
	78	return ERR_PTR(-EINVAL);
	79	if (((reiserfs_acl_header *) value)->a_version !=
	80	cpu_to_le32(REISERFS_ACL_VERSION))
	81	return ERR_PTR(-EINVAL);
	82	value = (char *)value + sizeof(reiserfs_acl_header);
	83	count = reiserfs_acl_count(size);
	84	if (count < 0)
	85	return ERR_PTR(-EINVAL);
	86	if (count == 0)
	87	return NULL;
	88	acl = posix_acl_alloc(count, GFP_NOFS);
	89	if (!acl)
	90	return ERR_PTR(-ENOMEM);
	91	for (n = 0; n < count; n++) {
	92	reiserfs_acl_entry entry = (reiserfs_acl_entry ) value;
	93	if ((char *)value + sizeof(reiserfs_acl_entry_short) > end)
	94	goto fail;
	95	acl->a_entries[n].e_tag = le16_to_cpu(entry->e_tag);
	96	acl->a_entries[n].e_perm = le16_to_cpu(entry->e_perm);
	97	switch (acl->a_entries[n].e_tag) {
	98	case ACL_USER_OBJ:
	99	case ACL_GROUP_OBJ:
	100	case ACL_MASK:
	101	case ACL_OTHER:
	102	value = (char *)value +
	103	sizeof(reiserfs_acl_entry_short);
	104	acl->a_entries[n].e_id = ACL_UNDEFINED_ID;
	105	break;
	106
	107	case ACL_USER:
	108	case ACL_GROUP:
	109	value = (char *)value + sizeof(reiserfs_acl_entry);
	110	if ((char *)value > end)
	111	goto fail;
	112	acl->a_entries[n].e_id = le32_to_cpu(entry->e_id);
	113	break;
	114
	115	default:
	116	goto fail;
	117	}
	118	}
	119	if (value != end)
	120	goto fail;
	121	return acl;
	122
	123	fail:
	124	posix_acl_release(acl);
	125	return ERR_PTR(-EINVAL);
	126	}
	127
	128	/*
	129	* Convert from in-memory to filesystem representation.
	130	*/
	131	static void posix_acl_to_disk(const struct posix_acl acl, size_t * size)
	132	{
	133	reiserfs_acl_header *ext_acl;
	134	char *e;
	135	int n;
	136
	137	*size = reiserfs_acl_size(acl->a_count);
	138	ext_acl = kmalloc(sizeof(reiserfs_acl_header) +
	139	acl->a_count *
	140	sizeof(reiserfs_acl_entry),
	141	GFP_NOFS);
	142	if (!ext_acl)
	143	return ERR_PTR(-ENOMEM);
	144	ext_acl->a_version = cpu_to_le32(REISERFS_ACL_VERSION);
	145	e = (char *)ext_acl + sizeof(reiserfs_acl_header);
	146	for (n = 0; n < acl->a_count; n++) {
	147	reiserfs_acl_entry entry = (reiserfs_acl_entry ) e;
	148	entry->e_tag = cpu_to_le16(acl->a_entries[n].e_tag);
	149	entry->e_perm = cpu_to_le16(acl->a_entries[n].e_perm);
	150	switch (acl->a_entries[n].e_tag) {
	151	case ACL_USER:
	152	case ACL_GROUP:
	153	entry->e_id = cpu_to_le32(acl->a_entries[n].e_id);
	154	e += sizeof(reiserfs_acl_entry);
	155	break;
	156
	157	case ACL_USER_OBJ:
	158	case ACL_GROUP_OBJ:
	159	case ACL_MASK:
	160	case ACL_OTHER:
	161	e += sizeof(reiserfs_acl_entry_short);
	162	break;
	163
	164	default:
	165	goto fail;
	166	}
	167	}
	168	return (char *)ext_acl;
	169
	170	fail:
	171	kfree(ext_acl);
	172	return ERR_PTR(-EINVAL);
	173	}
	174
	175	static inline void iset_acl(struct inode inode, struct posix_acl *i_acl,
	176	struct posix_acl *acl)
	177	{
	178	spin_lock(&inode->i_lock);
	179	if (*i_acl != ERR_PTR(-ENODATA))
	180	posix_acl_release(*i_acl);
	181	*i_acl = posix_acl_dup(acl);
	182	spin_unlock(&inode->i_lock);
	183	}
	184
	185	static inline struct posix_acl iget_acl(struct inode inode,
	186	struct posix_acl **i_acl)
	187	{
	188	struct posix_acl *acl = ERR_PTR(-ENODATA);
	189
	190	spin_lock(&inode->i_lock);
	191	if (*i_acl != ERR_PTR(-ENODATA))
	192	acl = posix_acl_dup(*i_acl);
	193	spin_unlock(&inode->i_lock);
	194
	195	return acl;
	196	}
	197
	198	/*
	199	* Inode operation get_posix_acl().
	200	*
	201	* inode->i_mutex: down
	202	* BKL held [before 2.5.x]
	203	*/
	204	struct posix_acl reiserfs_get_acl(struct inode inode, int type)
	205	{
	206	char name, value;
	207	struct posix_acl acl, *p_acl;
	208	int size;
	209	int retval;
	210	struct reiserfs_inode_info *reiserfs_i = REISERFS_I(inode);
	211
	212	switch (type) {
	213	case ACL_TYPE_ACCESS:
	214	name = POSIX_ACL_XATTR_ACCESS;
	215	p_acl = &reiserfs_i->i_acl_access;
	216	break;
	217	case ACL_TYPE_DEFAULT:
	218	name = POSIX_ACL_XATTR_DEFAULT;
	219	p_acl = &reiserfs_i->i_acl_default;
	220	break;
	221	default:
	222	return ERR_PTR(-EINVAL);
	223	}
	224
	225	acl = iget_acl(inode, p_acl);
	226	if (acl && !IS_ERR(acl))
	227	return acl;
	228	else if (PTR_ERR(acl) == -ENODATA)
	229	return NULL;
	230
	231	size = reiserfs_xattr_get(inode, name, NULL, 0);
	232	if (size < 0) {
	233	if (size == -ENODATA \|\| size == -ENOSYS) {
	234	*p_acl = ERR_PTR(-ENODATA);
	235	return NULL;
	236	}
	237	return ERR_PTR(size);
	238	}
	239
	240	value = kmalloc(size, GFP_NOFS);
	241	if (!value)
	242	return ERR_PTR(-ENOMEM);
	243
	244	retval = reiserfs_xattr_get(inode, name, value, size);
	245	if (retval == -ENODATA \|\| retval == -ENOSYS) {
	246	/* This shouldn't actually happen as it should have
	247	been caught above.. but just in case */
	248	acl = NULL;
	249	*p_acl = ERR_PTR(-ENODATA);
	250	} else if (retval < 0) {
	251	acl = ERR_PTR(retval);
	252	} else {
	253	acl = posix_acl_from_disk(value, retval);
	254	if (!IS_ERR(acl))
	255	iset_acl(inode, p_acl, acl);
	256	}
	257
	258	kfree(value);
	259	return acl;
	260	}
	261
	262	/*
	263	* Inode operation set_posix_acl().
	264	*
	265	* inode->i_mutex: down
	266	* BKL held [before 2.5.x]
	267	*/
	268	static int
	269	reiserfs_set_acl(struct inode inode, int type, struct posix_acl acl)
	270	{
	271	char *name;
	272	void *value = NULL;
	273	struct posix_acl **p_acl;
	274	size_t size = 0;
	275	int error;
	276	struct reiserfs_inode_info *reiserfs_i = REISERFS_I(inode);
	277
	278	if (S_ISLNK(inode->i_mode))
	279	return -EOPNOTSUPP;
	280
	281	switch (type) {
	282	case ACL_TYPE_ACCESS:
	283	name = POSIX_ACL_XATTR_ACCESS;
	284	p_acl = &reiserfs_i->i_acl_access;
	285	if (acl) {
	286	mode_t mode = inode->i_mode;
	287	error = posix_acl_equiv_mode(acl, &mode);
	288	if (error < 0)
	289	return error;
	290	else {
	291	inode->i_mode = mode;
	292	if (error == 0)
	293	acl = NULL;
	294	}
	295	}
	296	break;
	297	case ACL_TYPE_DEFAULT:
	298	name = POSIX_ACL_XATTR_DEFAULT;
	299	p_acl = &reiserfs_i->i_acl_default;
	300	if (!S_ISDIR(inode->i_mode))
	301	return acl ? -EACCES : 0;
	302	break;
	303	default:
	304	return -EINVAL;
	305	}
	306
	307	if (acl) {
	308	value = posix_acl_to_disk(acl, &size);
	309	if (IS_ERR(value))
	310	return (int)PTR_ERR(value);
	311	}
	312
	313	error = __reiserfs_xattr_set(inode, name, value, size, 0);
	314
	315	/*
	316	* Ensure that the inode gets dirtied if we're only using
	317	* the mode bits and an old ACL didn't exist. We don't need
	318	* to check if the inode is hashed here since we won't get
	319	* called by reiserfs_inherit_default_acl().
	320	*/
	321	if (error == -ENODATA) {
	322	error = 0;
	323	if (type == ACL_TYPE_ACCESS) {
	324	inode->i_ctime = CURRENT_TIME_SEC;
	325	mark_inode_dirty(inode);
	326	}
	327	}
	328
	329	kfree(value);
	330
	331	if (!error)
	332	iset_acl(inode, p_acl, acl);
	333
	334	return error;
	335	}
	336
	337	/* dir->i_mutex: locked,
	338	* inode is new and not released into the wild yet */
	339	int
	340	reiserfs_inherit_default_acl(struct inode dir, struct dentry dentry,
	341	struct inode *inode)
	342	{
	343	struct posix_acl *acl;
	344	int err = 0;
	345
	346	/* ACLs only get applied to files and directories */
	347	if (S_ISLNK(inode->i_mode))
	348	return 0;
	349
	350	/* ACLs can only be used on "new" objects, so if it's an old object
	351	* there is nothing to inherit from */
	352	if (get_inode_sd_version(dir) == STAT_DATA_V1)
	353	goto apply_umask;
	354
	355	/* Don't apply ACLs to objects in the .reiserfs_priv tree.. This
	356	* would be useless since permissions are ignored, and a pain because
	357	* it introduces locking cycles */
	358	if (IS_PRIVATE(dir)) {
	359	inode->i_flags \|= S_PRIVATE;
	360	goto apply_umask;
	361	}
	362
	363	acl = reiserfs_get_acl(dir, ACL_TYPE_DEFAULT);
	364	if (IS_ERR(acl)) {
	365	if (PTR_ERR(acl) == -ENODATA)
	366	goto apply_umask;
	367	return PTR_ERR(acl);
	368	}
	369
	370	if (acl) {
	371	struct posix_acl *acl_copy;
	372	mode_t mode = inode->i_mode;
	373	int need_acl;
	374
	375	/* Copy the default ACL to the default ACL of a new directory */
	376	if (S_ISDIR(inode->i_mode)) {
	377	err = reiserfs_set_acl(inode, ACL_TYPE_DEFAULT, acl);
	378	if (err)
	379	goto cleanup;
	380	}
	381
	382	/* Now we reconcile the new ACL and the mode,
	383	potentially modifying both */
	384	acl_copy = posix_acl_clone(acl, GFP_NOFS);
	385	if (!acl_copy) {
	386	err = -ENOMEM;
	387	goto cleanup;
	388	}
	389
	390	need_acl = posix_acl_create_masq(acl_copy, &mode);
	391	if (need_acl >= 0) {
	392	if (mode != inode->i_mode) {
	393	inode->i_mode = mode;
	394	}
	395
	396	/* If we need an ACL.. */
	397	if (need_acl > 0) {
	398	err =
	399	reiserfs_set_acl(inode, ACL_TYPE_ACCESS,
	400	acl_copy);
	401	if (err)
	402	goto cleanup_copy;
	403	}
	404	}
	405	cleanup_copy:
	406	posix_acl_release(acl_copy);
	407	cleanup:
	408	posix_acl_release(acl);
	409	} else {
	410	apply_umask:
	411	/* no ACL, apply umask */
	412	inode->i_mode &= ~current->fs->umask;
	413	}
	414
	415	return err;
	416	}
	417
	418	/* Looks up and caches the result of the default ACL.
	419	* We do this so that we don't need to carry the xattr_sem into
	420	* reiserfs_new_inode if we don't need to */
	421	int reiserfs_cache_default_acl(struct inode *inode)
	422	{
	423	int ret = 0;
	424	if (reiserfs_posixacl(inode->i_sb) && !IS_PRIVATE(inode)) {
	425	struct posix_acl *acl;
	426	acl = reiserfs_get_acl(inode, ACL_TYPE_DEFAULT);
	427	ret = (acl && !IS_ERR(acl));
	428	if (ret)
	429	posix_acl_release(acl);
	430	}
	431
	432	return ret;
	433	}
	434
	435	int reiserfs_acl_chmod(struct inode *inode)
	436	{
	437	struct posix_acl acl, clone;
	438	int error;
	439
	440	if (S_ISLNK(inode->i_mode))
	441	return -EOPNOTSUPP;
	442
	443	if (get_inode_sd_version(inode) == STAT_DATA_V1 \|\|
	444	!reiserfs_posixacl(inode->i_sb)) {
	445	return 0;
	446	}
	447
	448	acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS);
	449	if (!acl)
	450	return 0;
	451	if (IS_ERR(acl))
	452	return PTR_ERR(acl);
	453	clone = posix_acl_clone(acl, GFP_NOFS);
	454	posix_acl_release(acl);
	455	if (!clone)
	456	return -ENOMEM;
	457	error = posix_acl_chmod_masq(clone, inode->i_mode);
	458	if (!error)
	459	error = reiserfs_set_acl(inode, ACL_TYPE_ACCESS, clone);
	460	posix_acl_release(clone);
	461	return error;
	462	}
	463
	464	static int
	465	posix_acl_access_get(struct inode inode, const char name,
	466	void *buffer, size_t size)
	467	{
	468	if (strlen(name) != sizeof(POSIX_ACL_XATTR_ACCESS) - 1)
	469	return -EINVAL;
	470	return xattr_get_acl(inode, ACL_TYPE_ACCESS, buffer, size);
	471	}
	472
	473	static int
	474	posix_acl_access_set(struct inode inode, const char name,
	475	const void *value, size_t size, int flags)
	476	{
	477	if (strlen(name) != sizeof(POSIX_ACL_XATTR_ACCESS) - 1)
	478	return -EINVAL;
	479	return xattr_set_acl(inode, ACL_TYPE_ACCESS, value, size);
	480	}
	481
	482	static size_t posix_acl_access_list(struct inode inode, char list,
	483	size_t list_size, const char *name,
	484	size_t name_len)
	485	{
	486	const size_t size = sizeof(POSIX_ACL_XATTR_ACCESS);
	487	if (!reiserfs_posixacl(inode->i_sb))
	488	return 0;
	489	if (list && size <= list_size)
	490	memcpy(list, POSIX_ACL_XATTR_ACCESS, size);
	491	return size;
	492	}
	493
	494	struct xattr_handler reiserfs_posix_acl_access_handler = {
	495	.prefix = POSIX_ACL_XATTR_ACCESS,
	496	.get = posix_acl_access_get,
	497	.set = posix_acl_access_set,
	498	.list = posix_acl_access_list,
	499	};
	500
	501	static int
	502	posix_acl_default_get(struct inode inode, const char name,
	503	void *buffer, size_t size)
	504	{
	505	if (strlen(name) != sizeof(POSIX_ACL_XATTR_DEFAULT) - 1)
	506	return -EINVAL;
	507	return xattr_get_acl(inode, ACL_TYPE_DEFAULT, buffer, size);
	508	}
	509
	510	static int
	511	posix_acl_default_set(struct inode inode, const char name,
	512	const void *value, size_t size, int flags)
	513	{
	514	if (strlen(name) != sizeof(POSIX_ACL_XATTR_DEFAULT) - 1)
	515	return -EINVAL;
	516	return xattr_set_acl(inode, ACL_TYPE_DEFAULT, value, size);
	517	}
	518
	519	static size_t posix_acl_default_list(struct inode inode, char list,
	520	size_t list_size, const char *name,
	521	size_t name_len)
	522	{
	523	const size_t size = sizeof(POSIX_ACL_XATTR_DEFAULT);
	524	if (!reiserfs_posixacl(inode->i_sb))
	525	return 0;
	526	if (list && size <= list_size)
	527	memcpy(list, POSIX_ACL_XATTR_DEFAULT, size);
	528	return size;
	529	}
	530
	531	struct xattr_handler reiserfs_posix_acl_default_handler = {
	532	.prefix = POSIX_ACL_XATTR_DEFAULT,
	533	.get = posix_acl_default_get,
	534	.set = posix_acl_default_set,
	535	.list = posix_acl_default_list,
	536	};