fs/reiserfs/xattr_acl.c - kernel/msm-4.9 - Gitiles

 #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);
 }

 /*
  * 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);
 	}

 	if (IS_ERR(*p_acl)) {
 		if (PTR_ERR(*p_acl) == -ENODATA)
 			return NULL;
 	} else if (*p_acl != NULL)
 		return posix_acl_dup(*p_acl);

 	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))
 			*p_acl = posix_acl_dup(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;
 	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);
 	} else {
 		error = reiserfs_xattr_del(inode, name);
 		if (error == -ENODATA) {
 			/* This may seem odd here, but it means that the ACL was set
 			 * with a value representable with mode bits. If there was
 			 * an ACL before, reiserfs_xattr_del already dirtied the inode.
 			 */
 			mark_inode_dirty(inode);
 			error = 0;
 		}
 	}

 	kfree(value);

 	if (!error) {
 		/* Release the old one */
 		if (!IS_ERR(*p_acl) && *p_acl)
 			posix_acl_release(*p_acl);

 		if (acl == NULL)
 			*p_acl = ERR_PTR(-ENODATA);
 		else
 			*p_acl = posix_acl_dup(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_reiserfs_priv_object(dir)) {
 		reiserfs_mark_inode_private(inode);
 		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_reiserfs_priv_object(inode)) {
 		struct posix_acl *acl;
 		reiserfs_read_lock_xattr_i(inode);
 		reiserfs_read_lock_xattrs(inode->i_sb);
 		acl = reiserfs_get_acl(inode, ACL_TYPE_DEFAULT);
 		reiserfs_read_unlock_xattrs(inode->i_sb);
 		reiserfs_read_unlock_xattr_i(inode);
 		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;
 	}

 	reiserfs_read_lock_xattrs(inode->i_sb);
 	acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS);
 	reiserfs_read_unlock_xattrs(inode->i_sb);
 	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) {
 		int lock = !has_xattr_dir(inode);
 		reiserfs_write_lock_xattr_i(inode);
 		if (lock)
 			reiserfs_write_lock_xattrs(inode->i_sb);
 		else
 			reiserfs_read_lock_xattrs(inode->i_sb);
 		error = reiserfs_set_acl(inode, ACL_TYPE_ACCESS, clone);
 		if (lock)
 			reiserfs_write_unlock_xattrs(inode->i_sb);
 		else
 			reiserfs_read_unlock_xattrs(inode->i_sb);
 		reiserfs_write_unlock_xattr_i(inode);
 	}
 	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 int posix_acl_access_del(struct inode *inode, const char *name)
 {
 	struct reiserfs_inode_info *reiserfs_i = REISERFS_I(inode);
 	struct posix_acl **acl = &reiserfs_i->i_acl_access;
 	if (strlen(name) != sizeof(POSIX_ACL_XATTR_ACCESS) - 1)
 		return -EINVAL;
 	if (!IS_ERR(*acl) && *acl) {
 		posix_acl_release(*acl);
 		*acl = ERR_PTR(-ENODATA);
 	}

 	return 0;
 }

 static int
 posix_acl_access_list(struct inode *inode, const char *name, int namelen,
 		      char *out)
 {
 	int len = namelen;
 	if (!reiserfs_posixacl(inode->i_sb))
 		return 0;
 	if (out)
 		memcpy(out, name, len);

 	return len;
 }

 struct reiserfs_xattr_handler posix_acl_access_handler = {
 	.prefix = POSIX_ACL_XATTR_ACCESS,
 	.get = posix_acl_access_get,
 	.set = posix_acl_access_set,
 	.del = posix_acl_access_del,
 	.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 int posix_acl_default_del(struct inode *inode, const char *name)
 {
 	struct reiserfs_inode_info *reiserfs_i = REISERFS_I(inode);
 	struct posix_acl **acl = &reiserfs_i->i_acl_default;
 	if (strlen(name) != sizeof(POSIX_ACL_XATTR_DEFAULT) - 1)
 		return -EINVAL;
 	if (!IS_ERR(*acl) && *acl) {
 		posix_acl_release(*acl);
 		*acl = ERR_PTR(-ENODATA);
 	}

 	return 0;
 }

 static int
 posix_acl_default_list(struct inode *inode, const char *name, int namelen,
 		       char *out)
 {
 	int len = namelen;
 	if (!reiserfs_posixacl(inode->i_sb))
 		return 0;
 	if (out)
 		memcpy(out, name, len);

 	return len;
 }

 struct reiserfs_xattr_handler posix_acl_default_handler = {
 	.prefix = POSIX_ACL_XATTR_DEFAULT,
 	.get = posix_acl_default_get,
 	.set = posix_acl_default_set,
 	.del = posix_acl_default_del,
 	.list = posix_acl_default_list,
 };
	#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);
	}

	/*
	* 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);
	}

	if (IS_ERR(*p_acl)) {
	if (PTR_ERR(*p_acl) == -ENODATA)
	return NULL;
	} else if (*p_acl != NULL)
	return posix_acl_dup(*p_acl);

	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))
	*p_acl = posix_acl_dup(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;
	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);
	} else {
	error = reiserfs_xattr_del(inode, name);
	if (error == -ENODATA) {
	/* This may seem odd here, but it means that the ACL was set
	* with a value representable with mode bits. If there was
	* an ACL before, reiserfs_xattr_del already dirtied the inode.
	*/
	mark_inode_dirty(inode);
	error = 0;
	}
	}

	kfree(value);

	if (!error) {
	/* Release the old one */
	if (!IS_ERR(p_acl) && p_acl)
	posix_acl_release(*p_acl);

	if (acl == NULL)
	*p_acl = ERR_PTR(-ENODATA);
	else
	*p_acl = posix_acl_dup(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_reiserfs_priv_object(dir)) {
	reiserfs_mark_inode_private(inode);
	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_reiserfs_priv_object(inode)) {
	struct posix_acl *acl;
	reiserfs_read_lock_xattr_i(inode);
	reiserfs_read_lock_xattrs(inode->i_sb);
	acl = reiserfs_get_acl(inode, ACL_TYPE_DEFAULT);
	reiserfs_read_unlock_xattrs(inode->i_sb);
	reiserfs_read_unlock_xattr_i(inode);
	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;
	}

	reiserfs_read_lock_xattrs(inode->i_sb);
	acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS);
	reiserfs_read_unlock_xattrs(inode->i_sb);
	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) {
	int lock = !has_xattr_dir(inode);
	reiserfs_write_lock_xattr_i(inode);
	if (lock)
	reiserfs_write_lock_xattrs(inode->i_sb);
	else
	reiserfs_read_lock_xattrs(inode->i_sb);
	error = reiserfs_set_acl(inode, ACL_TYPE_ACCESS, clone);
	if (lock)
	reiserfs_write_unlock_xattrs(inode->i_sb);
	else
	reiserfs_read_unlock_xattrs(inode->i_sb);
	reiserfs_write_unlock_xattr_i(inode);
	}
	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 int posix_acl_access_del(struct inode inode, const char name)
	{
	struct reiserfs_inode_info *reiserfs_i = REISERFS_I(inode);
	struct posix_acl **acl = &reiserfs_i->i_acl_access;
	if (strlen(name) != sizeof(POSIX_ACL_XATTR_ACCESS) - 1)
	return -EINVAL;
	if (!IS_ERR(acl) && acl) {
	posix_acl_release(*acl);
	*acl = ERR_PTR(-ENODATA);
	}

	return 0;
	}

	static int
	posix_acl_access_list(struct inode inode, const char name, int namelen,
	char *out)
	{
	int len = namelen;
	if (!reiserfs_posixacl(inode->i_sb))
	return 0;
	if (out)
	memcpy(out, name, len);

	return len;
	}

	struct reiserfs_xattr_handler posix_acl_access_handler = {
	.prefix = POSIX_ACL_XATTR_ACCESS,
	.get = posix_acl_access_get,
	.set = posix_acl_access_set,
	.del = posix_acl_access_del,
	.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 int posix_acl_default_del(struct inode inode, const char name)
	{
	struct reiserfs_inode_info *reiserfs_i = REISERFS_I(inode);
	struct posix_acl **acl = &reiserfs_i->i_acl_default;
	if (strlen(name) != sizeof(POSIX_ACL_XATTR_DEFAULT) - 1)
	return -EINVAL;
	if (!IS_ERR(acl) && acl) {
	posix_acl_release(*acl);
	*acl = ERR_PTR(-ENODATA);
	}

	return 0;
	}

	static int
	posix_acl_default_list(struct inode inode, const char name, int namelen,
	char *out)
	{
	int len = namelen;
	if (!reiserfs_posixacl(inode->i_sb))
	return 0;
	if (out)
	memcpy(out, name, len);

	return len;
	}

	struct reiserfs_xattr_handler posix_acl_default_handler = {
	.prefix = POSIX_ACL_XATTR_DEFAULT,
	.get = posix_acl_default_get,
	.set = posix_acl_default_set,
	.del = posix_acl_default_del,
	.list = posix_acl_default_list,
	};