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/slab.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 reiserfs_transaction_handle *th,
 			    struct inode *inode, int type,
 			    struct posix_acl *acl);

 static int
 posix_acl_set(struct dentry *dentry, const char *name, const void *value,
 		size_t size, int flags, int type)
 {
 	struct inode *inode = dentry->d_inode;
 	struct posix_acl *acl;
 	int error, error2;
 	struct reiserfs_transaction_handle th;
 	size_t jcreate_blocks;
 	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;

 	/* Pessimism: We can't assume that anything from the xattr root up
 	 * has been created. */

 	jcreate_blocks = reiserfs_xattr_jcreate_nblocks(inode) +
 			 reiserfs_xattr_nblocks(inode, size) * 2;

 	reiserfs_write_lock(inode->i_sb);
 	error = journal_begin(&th, inode->i_sb, jcreate_blocks);
 	if (error == 0) {
 		error = reiserfs_set_acl(&th, inode, type, acl);
 		error2 = journal_end(&th, inode->i_sb, jcreate_blocks);
 		if (error2)
 			error = error2;
 	}
 	reiserfs_write_unlock(inode->i_sb);

       release_and_out:
 	posix_acl_release(acl);
 	return error;
 }

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

 	if (!reiserfs_posixacl(dentry->d_sb))
 		return -EOPNOTSUPP;

 	acl = reiserfs_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;
 }

 /*
  * 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;
 	int size;
 	int retval;

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

 	switch (type) {
 	case ACL_TYPE_ACCESS:
 		name = POSIX_ACL_XATTR_ACCESS;
 		break;
 	case ACL_TYPE_DEFAULT:
 		name = POSIX_ACL_XATTR_DEFAULT;
 		break;
 	default:
 		BUG();
 	}

 	size = reiserfs_xattr_get(inode, name, NULL, 0);
 	if (size < 0) {
 		if (size == -ENODATA || size == -ENOSYS) {
 			set_cached_acl(inode, type, NULL);
 			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;
 	} else if (retval < 0) {
 		acl = ERR_PTR(retval);
 	} else {
 		acl = posix_acl_from_disk(value, retval);
 	}
 	if (!IS_ERR(acl))
 		set_cached_acl(inode, type, 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 reiserfs_transaction_handle *th, struct inode *inode,
 		 int type, struct posix_acl *acl)
 {
 	char *name;
 	void *value = NULL;
 	size_t size = 0;
 	int error;

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

 	switch (type) {
 	case ACL_TYPE_ACCESS:
 		name = POSIX_ACL_XATTR_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;
 		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_handle(th, 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)
 		set_cached_acl(inode, type, acl);

 	return error;
 }

 /* dir->i_mutex: locked,
  * inode is new and not released into the wild yet */
 int
 reiserfs_inherit_default_acl(struct reiserfs_transaction_handle *th,
 			     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))
 		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(th, 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(th, 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_umask();
 	}

 	return err;
 }

 /* This is used to cache the default acl before a new object is created.
  * The biggest reason for this is to get an idea of how many blocks will
  * actually be required for the create operation if we must inherit an ACL.
  * An ACL write can add up to 3 object creations and an additional file write
  * so we'd prefer not to reserve that many blocks in the journal if we can.
  * It also has the advantage of not loading the ACL with a transaction open,
  * this may seem silly, but if the owner of the directory is doing the
  * creation, the ACL may not be loaded since the permissions wouldn't require
  * it.
  * We return the number of blocks required for the transaction.
  */
 int reiserfs_cache_default_acl(struct inode *inode)
 {
 	struct posix_acl *acl;
 	int nblocks = 0;

 	if (IS_PRIVATE(inode))
 		return 0;

 	acl = reiserfs_get_acl(inode, ACL_TYPE_DEFAULT);

 	if (acl && !IS_ERR(acl)) {
 		int size = reiserfs_acl_size(acl->a_count);

 		/* Other xattrs can be created during inode creation. We don't
 		 * want to claim too many blocks, so we check to see if we
 		 * we need to create the tree to the xattrs, and then we
 		 * just want two files. */
 		nblocks = reiserfs_xattr_jcreate_nblocks(inode);
 		nblocks += JOURNAL_BLOCKS_PER_OBJECT(inode->i_sb);

 		REISERFS_I(inode)->i_flags |= i_has_xattr_dir;

 		/* We need to account for writes + bitmaps for two files */
 		nblocks += reiserfs_xattr_nblocks(inode, size) * 4;
 		posix_acl_release(acl);
 	}

 	return nblocks;
 }

 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_write_unlock(inode->i_sb);
 	acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS);
 	reiserfs_write_lock(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) {
 		struct reiserfs_transaction_handle th;
 		size_t size = reiserfs_xattr_nblocks(inode,
 					     reiserfs_acl_size(clone->a_count));
 		reiserfs_write_lock(inode->i_sb);
 		error = journal_begin(&th, inode->i_sb, size * 2);
 		if (!error) {
 			int error2;
 			error = reiserfs_set_acl(&th, inode, ACL_TYPE_ACCESS,
 						 clone);
 			error2 = journal_end(&th, inode->i_sb, size * 2);
 			if (error2)
 				error = error2;
 		}
 		reiserfs_write_unlock(inode->i_sb);
 	}
 	posix_acl_release(clone);
 	return error;
 }

 static size_t posix_acl_access_list(struct dentry *dentry, char *list,
 				    size_t list_size, const char *name,
 				    size_t name_len, int type)
 {
 	const size_t size = sizeof(POSIX_ACL_XATTR_ACCESS);
 	if (!reiserfs_posixacl(dentry->d_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,
 	.flags = ACL_TYPE_ACCESS,
 	.get = posix_acl_get,
 	.set = posix_acl_set,
 	.list = posix_acl_access_list,
 };

 static size_t posix_acl_default_list(struct dentry *dentry, char *list,
 				     size_t list_size, const char *name,
 				     size_t name_len, int type)
 {
 	const size_t size = sizeof(POSIX_ACL_XATTR_DEFAULT);
 	if (!reiserfs_posixacl(dentry->d_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,
 	.flags = ACL_TYPE_DEFAULT,
 	.get = posix_acl_get,
 	.set = posix_acl_set,
 	.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/slab.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 reiserfs_transaction_handle *th,
	struct inode *inode, int type,
	struct posix_acl *acl);

	static int
	posix_acl_set(struct dentry dentry, const char name, const void *value,
	size_t size, int flags, int type)
	{
	struct inode *inode = dentry->d_inode;
	struct posix_acl *acl;
	int error, error2;
	struct reiserfs_transaction_handle th;
	size_t jcreate_blocks;
	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;

	/* Pessimism: We can't assume that anything from the xattr root up
	* has been created. */

	jcreate_blocks = reiserfs_xattr_jcreate_nblocks(inode) +
	reiserfs_xattr_nblocks(inode, size) * 2;

	reiserfs_write_lock(inode->i_sb);
	error = journal_begin(&th, inode->i_sb, jcreate_blocks);
	if (error == 0) {
	error = reiserfs_set_acl(&th, inode, type, acl);
	error2 = journal_end(&th, inode->i_sb, jcreate_blocks);
	if (error2)
	error = error2;
	}
	reiserfs_write_unlock(inode->i_sb);

	release_and_out:
	posix_acl_release(acl);
	return error;
	}

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

	if (!reiserfs_posixacl(dentry->d_sb))
	return -EOPNOTSUPP;

	acl = reiserfs_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;
	}

	/*
	* 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;
	int size;
	int retval;

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

	switch (type) {
	case ACL_TYPE_ACCESS:
	name = POSIX_ACL_XATTR_ACCESS;
	break;
	case ACL_TYPE_DEFAULT:
	name = POSIX_ACL_XATTR_DEFAULT;
	break;
	default:
	BUG();
	}

	size = reiserfs_xattr_get(inode, name, NULL, 0);
	if (size < 0) {
	if (size == -ENODATA \|\| size == -ENOSYS) {
	set_cached_acl(inode, type, NULL);
	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;
	} else if (retval < 0) {
	acl = ERR_PTR(retval);
	} else {
	acl = posix_acl_from_disk(value, retval);
	}
	if (!IS_ERR(acl))
	set_cached_acl(inode, type, 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 reiserfs_transaction_handle th, struct inode inode,
	int type, struct posix_acl *acl)
	{
	char *name;
	void *value = NULL;
	size_t size = 0;
	int error;

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

	switch (type) {
	case ACL_TYPE_ACCESS:
	name = POSIX_ACL_XATTR_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;
	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_handle(th, 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)
	set_cached_acl(inode, type, acl);

	return error;
	}

	/* dir->i_mutex: locked,
	* inode is new and not released into the wild yet */
	int
	reiserfs_inherit_default_acl(struct reiserfs_transaction_handle *th,
	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))
	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(th, 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(th, 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_umask();
	}

	return err;
	}

	/* This is used to cache the default acl before a new object is created.
	* The biggest reason for this is to get an idea of how many blocks will
	* actually be required for the create operation if we must inherit an ACL.
	* An ACL write can add up to 3 object creations and an additional file write
	* so we'd prefer not to reserve that many blocks in the journal if we can.
	* It also has the advantage of not loading the ACL with a transaction open,
	* this may seem silly, but if the owner of the directory is doing the
	* creation, the ACL may not be loaded since the permissions wouldn't require
	* it.
	* We return the number of blocks required for the transaction.
	*/
	int reiserfs_cache_default_acl(struct inode *inode)
	{
	struct posix_acl *acl;
	int nblocks = 0;

	if (IS_PRIVATE(inode))
	return 0;

	acl = reiserfs_get_acl(inode, ACL_TYPE_DEFAULT);

	if (acl && !IS_ERR(acl)) {
	int size = reiserfs_acl_size(acl->a_count);

	/* Other xattrs can be created during inode creation. We don't
	* want to claim too many blocks, so we check to see if we
	* we need to create the tree to the xattrs, and then we
	* just want two files. */
	nblocks = reiserfs_xattr_jcreate_nblocks(inode);
	nblocks += JOURNAL_BLOCKS_PER_OBJECT(inode->i_sb);

	REISERFS_I(inode)->i_flags \|= i_has_xattr_dir;

	/* We need to account for writes + bitmaps for two files */
	nblocks += reiserfs_xattr_nblocks(inode, size) * 4;
	posix_acl_release(acl);
	}

	return nblocks;
	}

	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_write_unlock(inode->i_sb);
	acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS);
	reiserfs_write_lock(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) {
	struct reiserfs_transaction_handle th;
	size_t size = reiserfs_xattr_nblocks(inode,
	reiserfs_acl_size(clone->a_count));
	reiserfs_write_lock(inode->i_sb);
	error = journal_begin(&th, inode->i_sb, size * 2);
	if (!error) {
	int error2;
	error = reiserfs_set_acl(&th, inode, ACL_TYPE_ACCESS,
	clone);
	error2 = journal_end(&th, inode->i_sb, size * 2);
	if (error2)
	error = error2;
	}
	reiserfs_write_unlock(inode->i_sb);
	}
	posix_acl_release(clone);
	return error;
	}

	static size_t posix_acl_access_list(struct dentry dentry, char list,
	size_t list_size, const char *name,
	size_t name_len, int type)
	{
	const size_t size = sizeof(POSIX_ACL_XATTR_ACCESS);
	if (!reiserfs_posixacl(dentry->d_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,
	.flags = ACL_TYPE_ACCESS,
	.get = posix_acl_get,
	.set = posix_acl_set,
	.list = posix_acl_access_list,
	};

	static size_t posix_acl_default_list(struct dentry dentry, char list,
	size_t list_size, const char *name,
	size_t name_len, int type)
	{
	const size_t size = sizeof(POSIX_ACL_XATTR_DEFAULT);
	if (!reiserfs_posixacl(dentry->d_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,
	.flags = ACL_TYPE_DEFAULT,
	.get = posix_acl_get,
	.set = posix_acl_set,
	.list = posix_acl_default_list,
	};