fs/ext3/acl.c - LeafOS-Devices/android_kernel_samsung_gta4xl - Gitiles

 /*
  * linux/fs/ext3/acl.c
  *
  * Copyright (C) 2001-2003 Andreas Gruenbacher, <agruen@suse.de>
  */

 #include <linux/init.h>
 #include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/fs.h>
 #include <linux/ext3_jbd.h>
 #include <linux/ext3_fs.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_KERNEL);
 	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 = (ext3_acl_header *)kmalloc(sizeof(ext3_acl_header) +
 		acl->a_count * sizeof(ext3_acl_entry), GFP_KERNEL);
 	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);
 }

 static inline struct posix_acl *
 ext3_iget_acl(struct inode *inode, struct posix_acl **i_acl)
 {
 	struct posix_acl *acl = EXT3_ACL_NOT_CACHED;

 	spin_lock(&inode->i_lock);
 	if (*i_acl != EXT3_ACL_NOT_CACHED)
 		acl = posix_acl_dup(*i_acl);
 	spin_unlock(&inode->i_lock);

 	return acl;
 }

 static inline void
 ext3_iset_acl(struct inode *inode, struct posix_acl **i_acl,
                   struct posix_acl *acl)
 {
 	spin_lock(&inode->i_lock);
 	if (*i_acl != EXT3_ACL_NOT_CACHED)
 		posix_acl_release(*i_acl);
 	*i_acl = posix_acl_dup(acl);
 	spin_unlock(&inode->i_lock);
 }

 /*
  * Inode operation get_posix_acl().
  *
  * inode->i_mutex: don't care
  */
 static struct posix_acl *
 ext3_get_acl(struct inode *inode, int type)
 {
 	struct ext3_inode_info *ei = EXT3_I(inode);
 	int name_index;
 	char *value = NULL;
 	struct posix_acl *acl;
 	int retval;

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

 	switch(type) {
 		case ACL_TYPE_ACCESS:
 			acl = ext3_iget_acl(inode, &ei->i_acl);
 			if (acl != EXT3_ACL_NOT_CACHED)
 				return acl;
 			name_index = EXT3_XATTR_INDEX_POSIX_ACL_ACCESS;
 			break;

 		case ACL_TYPE_DEFAULT:
 			acl = ext3_iget_acl(inode, &ei->i_default_acl);
 			if (acl != EXT3_ACL_NOT_CACHED)
 				return acl;
 			name_index = EXT3_XATTR_INDEX_POSIX_ACL_DEFAULT;
 			break;

 		default:
 			return ERR_PTR(-EINVAL);
 	}
 	retval = ext3_xattr_get(inode, name_index, "", NULL, 0);
 	if (retval > 0) {
 		value = kmalloc(retval, GFP_KERNEL);
 		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)) {
 		switch(type) {
 			case ACL_TYPE_ACCESS:
 				ext3_iset_acl(inode, &ei->i_acl, acl);
 				break;

 			case ACL_TYPE_DEFAULT:
 				ext3_iset_acl(inode, &ei->i_default_acl, acl);
 				break;
 		}
 	}
 	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)
 {
 	struct ext3_inode_info *ei = EXT3_I(inode);
 	int name_index;
 	void *value = NULL;
 	size_t size;
 	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) {
 				mode_t mode = inode->i_mode;
 				error = posix_acl_equiv_mode(acl, &mode);
 				if (error < 0)
 					return error;
 				else {
 					inode->i_mode = mode;
 					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) {
 		switch(type) {
 			case ACL_TYPE_ACCESS:
 				ext3_iset_acl(inode, &ei->i_acl, acl);
 				break;

 			case ACL_TYPE_DEFAULT:
 				ext3_iset_acl(inode, &ei->i_default_acl, acl);
 				break;
 		}
 	}
 	return error;
 }

 static int
 ext3_check_acl(struct inode *inode, int mask)
 {
 	struct posix_acl *acl = ext3_get_acl(inode, ACL_TYPE_ACCESS);

 	if (IS_ERR(acl))
 		return PTR_ERR(acl);
 	if (acl) {
 		int error = posix_acl_permission(inode, acl, mask);
 		posix_acl_release(acl);
 		return error;
 	}

 	return -EAGAIN;
 }

 int
 ext3_permission(struct inode *inode, int mask, struct nameidata *nd)
 {
 	return generic_permission(inode, mask, ext3_check_acl);
 }

 /*
  * 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->fs->umask;
 	}
 	if (test_opt(inode->i_sb, POSIX_ACL) && acl) {
 		struct posix_acl *clone;
 		mode_t mode;

 		if (S_ISDIR(inode->i_mode)) {
 			error = ext3_set_acl(handle, inode,
 					     ACL_TYPE_DEFAULT, acl);
 			if (error)
 				goto cleanup;
 		}
 		clone = posix_acl_clone(acl, GFP_KERNEL);
 		error = -ENOMEM;
 		if (!clone)
 			goto cleanup;

 		mode = inode->i_mode;
 		error = posix_acl_create_masq(clone, &mode);
 		if (error >= 0) {
 			inode->i_mode = mode;
 			if (error > 0) {
 				/* This is an extended ACL */
 				error = ext3_set_acl(handle, inode,
 						     ACL_TYPE_ACCESS, clone);
 			}
 		}
 		posix_acl_release(clone);
 	}
 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, *clone;
         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);
 	clone = posix_acl_clone(acl, GFP_KERNEL);
 	posix_acl_release(acl);
 	if (!clone)
 		return -ENOMEM;
 	error = posix_acl_chmod_masq(clone, inode->i_mode);
 	if (!error) {
 		handle_t *handle;
 		int retries = 0;

 	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, clone);
 		ext3_journal_stop(handle);
 		if (error == -ENOSPC &&
 		    ext3_should_retry_alloc(inode->i_sb, &retries))
 			goto retry;
 	}
 out:
 	posix_acl_release(clone);
 	return error;
 }

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

 	if (!test_opt(inode->i_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 inode *inode, char *list, size_t list_len,
 			    const char *name, size_t name_len)
 {
 	const size_t size = sizeof(POSIX_ACL_XATTR_DEFAULT);

 	if (!test_opt(inode->i_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 inode *inode, int type, void *buffer, size_t size)
 {
 	struct posix_acl *acl;
 	int error;

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

 	acl = ext3_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;
 }

 static int
 ext3_xattr_get_acl_access(struct inode *inode, const char *name,
 			  void *buffer, size_t size)
 {
 	if (strcmp(name, "") != 0)
 		return -EINVAL;
 	return ext3_xattr_get_acl(inode, ACL_TYPE_ACCESS, buffer, size);
 }

 static int
 ext3_xattr_get_acl_default(struct inode *inode, const char *name,
 			   void *buffer, size_t size)
 {
 	if (strcmp(name, "") != 0)
 		return -EINVAL;
 	return ext3_xattr_get_acl(inode, ACL_TYPE_DEFAULT, buffer, size);
 }

 static int
 ext3_xattr_set_acl(struct inode *inode, int type, const void *value,
 		   size_t size)
 {
 	handle_t *handle;
 	struct posix_acl *acl;
 	int error, retries = 0;

 	if (!test_opt(inode->i_sb, POSIX_ACL))
 		return -EOPNOTSUPP;
 	if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
 		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;
 }

 static int
 ext3_xattr_set_acl_access(struct inode *inode, const char *name,
 			  const void *value, size_t size, int flags)
 {
 	if (strcmp(name, "") != 0)
 		return -EINVAL;
 	return ext3_xattr_set_acl(inode, ACL_TYPE_ACCESS, value, size);
 }

 static int
 ext3_xattr_set_acl_default(struct inode *inode, const char *name,
 			   const void *value, size_t size, int flags)
 {
 	if (strcmp(name, "") != 0)
 		return -EINVAL;
 	return ext3_xattr_set_acl(inode, ACL_TYPE_DEFAULT, value, size);
 }

 struct xattr_handler ext3_xattr_acl_access_handler = {
 	.prefix	= POSIX_ACL_XATTR_ACCESS,
 	.list	= ext3_xattr_list_acl_access,
 	.get	= ext3_xattr_get_acl_access,
 	.set	= ext3_xattr_set_acl_access,
 };

 struct xattr_handler ext3_xattr_acl_default_handler = {
 	.prefix	= POSIX_ACL_XATTR_DEFAULT,
 	.list	= ext3_xattr_list_acl_default,
 	.get	= ext3_xattr_get_acl_default,
 	.set	= ext3_xattr_set_acl_default,
 };
	/*
	* linux/fs/ext3/acl.c
	*
	* Copyright (C) 2001-2003 Andreas Gruenbacher, <agruen@suse.de>
	*/

	#include <linux/init.h>
	#include <linux/sched.h>
	#include <linux/slab.h>
	#include <linux/fs.h>
	#include <linux/ext3_jbd.h>
	#include <linux/ext3_fs.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_KERNEL);
	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 = (ext3_acl_header *)kmalloc(sizeof(ext3_acl_header) +
	acl->a_count * sizeof(ext3_acl_entry), GFP_KERNEL);
	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);
	}

	static inline struct posix_acl *
	ext3_iget_acl(struct inode inode, struct posix_acl *i_acl)
	{
	struct posix_acl *acl = EXT3_ACL_NOT_CACHED;

	spin_lock(&inode->i_lock);
	if (*i_acl != EXT3_ACL_NOT_CACHED)
	acl = posix_acl_dup(*i_acl);
	spin_unlock(&inode->i_lock);

	return acl;
	}

	static inline void
	ext3_iset_acl(struct inode inode, struct posix_acl *i_acl,
	struct posix_acl *acl)
	{
	spin_lock(&inode->i_lock);
	if (*i_acl != EXT3_ACL_NOT_CACHED)
	posix_acl_release(*i_acl);
	*i_acl = posix_acl_dup(acl);
	spin_unlock(&inode->i_lock);
	}

	/*
	* Inode operation get_posix_acl().
	*
	* inode->i_mutex: don't care
	*/
	static struct posix_acl *
	ext3_get_acl(struct inode *inode, int type)
	{
	struct ext3_inode_info *ei = EXT3_I(inode);
	int name_index;
	char *value = NULL;
	struct posix_acl *acl;
	int retval;

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

	switch(type) {
	case ACL_TYPE_ACCESS:
	acl = ext3_iget_acl(inode, &ei->i_acl);
	if (acl != EXT3_ACL_NOT_CACHED)
	return acl;
	name_index = EXT3_XATTR_INDEX_POSIX_ACL_ACCESS;
	break;

	case ACL_TYPE_DEFAULT:
	acl = ext3_iget_acl(inode, &ei->i_default_acl);
	if (acl != EXT3_ACL_NOT_CACHED)
	return acl;
	name_index = EXT3_XATTR_INDEX_POSIX_ACL_DEFAULT;
	break;

	default:
	return ERR_PTR(-EINVAL);
	}
	retval = ext3_xattr_get(inode, name_index, "", NULL, 0);
	if (retval > 0) {
	value = kmalloc(retval, GFP_KERNEL);
	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)) {
	switch(type) {
	case ACL_TYPE_ACCESS:
	ext3_iset_acl(inode, &ei->i_acl, acl);
	break;

	case ACL_TYPE_DEFAULT:
	ext3_iset_acl(inode, &ei->i_default_acl, acl);
	break;
	}
	}
	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)
	{
	struct ext3_inode_info *ei = EXT3_I(inode);
	int name_index;
	void *value = NULL;
	size_t size;
	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) {
	mode_t mode = inode->i_mode;
	error = posix_acl_equiv_mode(acl, &mode);
	if (error < 0)
	return error;
	else {
	inode->i_mode = mode;
	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) {
	switch(type) {
	case ACL_TYPE_ACCESS:
	ext3_iset_acl(inode, &ei->i_acl, acl);
	break;

	case ACL_TYPE_DEFAULT:
	ext3_iset_acl(inode, &ei->i_default_acl, acl);
	break;
	}
	}
	return error;
	}

	static int
	ext3_check_acl(struct inode *inode, int mask)
	{
	struct posix_acl *acl = ext3_get_acl(inode, ACL_TYPE_ACCESS);

	if (IS_ERR(acl))
	return PTR_ERR(acl);
	if (acl) {
	int error = posix_acl_permission(inode, acl, mask);
	posix_acl_release(acl);
	return error;
	}

	return -EAGAIN;
	}

	int
	ext3_permission(struct inode inode, int mask, struct nameidata nd)
	{
	return generic_permission(inode, mask, ext3_check_acl);
	}

	/*
	* 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->fs->umask;
	}
	if (test_opt(inode->i_sb, POSIX_ACL) && acl) {
	struct posix_acl *clone;
	mode_t mode;

	if (S_ISDIR(inode->i_mode)) {
	error = ext3_set_acl(handle, inode,
	ACL_TYPE_DEFAULT, acl);
	if (error)
	goto cleanup;
	}
	clone = posix_acl_clone(acl, GFP_KERNEL);
	error = -ENOMEM;
	if (!clone)
	goto cleanup;

	mode = inode->i_mode;
	error = posix_acl_create_masq(clone, &mode);
	if (error >= 0) {
	inode->i_mode = mode;
	if (error > 0) {
	/* This is an extended ACL */
	error = ext3_set_acl(handle, inode,
	ACL_TYPE_ACCESS, clone);
	}
	}
	posix_acl_release(clone);
	}
	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, clone;
	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);
	clone = posix_acl_clone(acl, GFP_KERNEL);
	posix_acl_release(acl);
	if (!clone)
	return -ENOMEM;
	error = posix_acl_chmod_masq(clone, inode->i_mode);
	if (!error) {
	handle_t *handle;
	int retries = 0;

	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, clone);
	ext3_journal_stop(handle);
	if (error == -ENOSPC &&
	ext3_should_retry_alloc(inode->i_sb, &retries))
	goto retry;
	}
	out:
	posix_acl_release(clone);
	return error;
	}

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

	if (!test_opt(inode->i_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 inode inode, char list, size_t list_len,
	const char *name, size_t name_len)
	{
	const size_t size = sizeof(POSIX_ACL_XATTR_DEFAULT);

	if (!test_opt(inode->i_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 inode inode, int type, void buffer, size_t size)
	{
	struct posix_acl *acl;
	int error;

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

	acl = ext3_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;
	}

	static int
	ext3_xattr_get_acl_access(struct inode inode, const char name,
	void *buffer, size_t size)
	{
	if (strcmp(name, "") != 0)
	return -EINVAL;
	return ext3_xattr_get_acl(inode, ACL_TYPE_ACCESS, buffer, size);
	}

	static int
	ext3_xattr_get_acl_default(struct inode inode, const char name,
	void *buffer, size_t size)
	{
	if (strcmp(name, "") != 0)
	return -EINVAL;
	return ext3_xattr_get_acl(inode, ACL_TYPE_DEFAULT, buffer, size);
	}

	static int
	ext3_xattr_set_acl(struct inode inode, int type, const void value,
	size_t size)
	{
	handle_t *handle;
	struct posix_acl *acl;
	int error, retries = 0;

	if (!test_opt(inode->i_sb, POSIX_ACL))
	return -EOPNOTSUPP;
	if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
	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;
	}

	static int
	ext3_xattr_set_acl_access(struct inode inode, const char name,
	const void *value, size_t size, int flags)
	{
	if (strcmp(name, "") != 0)
	return -EINVAL;
	return ext3_xattr_set_acl(inode, ACL_TYPE_ACCESS, value, size);
	}

	static int
	ext3_xattr_set_acl_default(struct inode inode, const char name,
	const void *value, size_t size, int flags)
	{
	if (strcmp(name, "") != 0)
	return -EINVAL;
	return ext3_xattr_set_acl(inode, ACL_TYPE_DEFAULT, value, size);
	}

	struct xattr_handler ext3_xattr_acl_access_handler = {
	.prefix = POSIX_ACL_XATTR_ACCESS,
	.list = ext3_xattr_list_acl_access,
	.get = ext3_xattr_get_acl_access,
	.set = ext3_xattr_set_acl_access,
	};

	struct xattr_handler ext3_xattr_acl_default_handler = {
	.prefix = POSIX_ACL_XATTR_DEFAULT,
	.list = ext3_xattr_list_acl_default,
	.get = ext3_xattr_get_acl_default,
	.set = ext3_xattr_set_acl_default,
	};