[GitHub/LineageOS/android_kernel_motorola_exynos9610.git] / fs / reiserfs / xattr_acl.c

// SPDX-License-Identifier: GPL-2.0
#include <linux/capability.h>
#include <linux/fs.h>
#include <linux/posix_acl.h>
#include "reiserfs.h"
#include <linux/errno.h>
#include <linux/pagemap.h>
#include <linux/xattr.h>
#include <linux/slab.h>
#include <linux/posix_acl_xattr.h>
#include "xattr.h"
#include "acl.h"
#include <linux/uaccess.h>

static int __reiserfs_set_acl(struct reiserfs_transaction_handle *th,
			    struct inode *inode, int type,
			    struct posix_acl *acl);


int
reiserfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
{
	int error, error2;
	struct reiserfs_transaction_handle th;
	size_t jcreate_blocks;
	int size = acl ? posix_acl_xattr_size(acl->a_count) : 0;
	int update_mode = 0;
	umode_t mode = inode->i_mode;

	/*
	 * 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);
	reiserfs_write_unlock(inode->i_sb);
	if (error == 0) {
		if (type == ACL_TYPE_ACCESS && acl) {
			error = posix_acl_update_mode(inode, &mode, &acl);
			if (error)
				goto unlock;
			update_mode = 1;
		}
		error = __reiserfs_set_acl(&th, inode, type, acl);
		if (!error && update_mode)
			inode->i_mode = mode;
unlock:
		reiserfs_write_lock(inode->i_sb);
		error2 = journal_end(&th);
		reiserfs_write_unlock(inode->i_sb);
		if (error2)
			error = error2;
	}

	return error;
}

/*
 * Convert from filesystem to in-memory representation.
 */
static struct posix_acl *reiserfs_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);
			break;

		case ACL_USER:
			value = (char *)value + sizeof(reiserfs_acl_entry);
			if ((char *)value > end)
				goto fail;
			acl->a_entries[n].e_uid = 
				make_kuid(&init_user_ns,
					  le32_to_cpu(entry->e_id));
			break;
		case ACL_GROUP:
			value = (char *)value + sizeof(reiserfs_acl_entry);
			if ((char *)value > end)
				goto fail;
			acl->a_entries[n].e_gid =
				make_kgid(&init_user_ns,
					  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 *reiserfs_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++) {
		const struct posix_acl_entry *acl_e = &acl->a_entries[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:
			entry->e_id = cpu_to_le32(
				from_kuid(&init_user_ns, acl_e->e_uid));
			e += sizeof(reiserfs_acl_entry);
			break;
		case ACL_GROUP:
			entry->e_id = cpu_to_le32(
				from_kgid(&init_user_ns, acl_e->e_gid));
			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;

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

	size = reiserfs_xattr_get(inode, name, NULL, 0);
	if (size < 0) {
		if (size == -ENODATA || size == -ENOSYS)
			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 = reiserfs_posix_acl_from_disk(value, retval);
	}

	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;

	switch (type) {
	case ACL_TYPE_ACCESS:
		name = XATTR_NAME_POSIX_ACL_ACCESS;
		break;
	case ACL_TYPE_DEFAULT:
		name = XATTR_NAME_POSIX_ACL_DEFAULT;
		if (!S_ISDIR(inode->i_mode))
			return acl ? -EACCES : 0;
		break;
	default:
		return -EINVAL;
	}

	if (acl) {
		value = reiserfs_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(inode);
			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 *default_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;
	}

	err = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl);
	if (err)
		return err;

	if (default_acl) {
		err = __reiserfs_set_acl(th, inode, ACL_TYPE_DEFAULT,
					 default_acl);
		posix_acl_release(default_acl);
	}
	if (acl) {
		if (!err)
			err = __reiserfs_set_acl(th, inode, ACL_TYPE_ACCESS,
						 acl);
		posix_acl_release(acl);
	}

	return err;

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 = 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;
}

/*
 * Called under i_mutex
 */
int reiserfs_acl_chmod(struct inode *inode)
{
	if (IS_PRIVATE(inode))
		return 0;
	if (get_inode_sd_version(inode) == STAT_DATA_V1 ||
	    !reiserfs_posixacl(inode->i_sb))
		return 0;

	return posix_acl_chmod(inode, inode->i_mode);
}
Commit	Line	Data
	1	// SPDX-License-Identifier: GPL-2.0
	2	#include <linux/capability.h>
	3	#include <linux/fs.h>
	4	#include <linux/posix_acl.h>
	5	#include "reiserfs.h"
	6	#include <linux/errno.h>
	7	#include <linux/pagemap.h>
	8	#include <linux/xattr.h>
	9	#include <linux/slab.h>
	10	#include <linux/posix_acl_xattr.h>
	11	#include "xattr.h"
	12	#include "acl.h"
	13	#include <linux/uaccess.h>
	14
	15	static int __reiserfs_set_acl(struct reiserfs_transaction_handle *th,
	16	struct inode *inode, int type,
	17	struct posix_acl *acl);
	18
	19
	20	int
	21	reiserfs_set_acl(struct inode inode, struct posix_acl acl, int type)
	22	{
	23	int error, error2;
	24	struct reiserfs_transaction_handle th;
	25	size_t jcreate_blocks;
	26	int size = acl ? posix_acl_xattr_size(acl->a_count) : 0;
	27	int update_mode = 0;
	28	umode_t mode = inode->i_mode;
	29
	30	/*
	31	* Pessimism: We can't assume that anything from the xattr root up
	32	* has been created.
	33	*/
	34
	35	jcreate_blocks = reiserfs_xattr_jcreate_nblocks(inode) +
	36	reiserfs_xattr_nblocks(inode, size) * 2;
	37
	38	reiserfs_write_lock(inode->i_sb);
	39	error = journal_begin(&th, inode->i_sb, jcreate_blocks);
	40	reiserfs_write_unlock(inode->i_sb);
	41	if (error == 0) {
	42	if (type == ACL_TYPE_ACCESS && acl) {
	43	error = posix_acl_update_mode(inode, &mode, &acl);
	44	if (error)
	45	goto unlock;
	46	update_mode = 1;
	47	}
	48	error = __reiserfs_set_acl(&th, inode, type, acl);
	49	if (!error && update_mode)
	50	inode->i_mode = mode;
	51	unlock:
	52	reiserfs_write_lock(inode->i_sb);
	53	error2 = journal_end(&th);
	54	reiserfs_write_unlock(inode->i_sb);
	55	if (error2)
	56	error = error2;
	57	}
	58
	59	return error;
	60	}
	61
	62	/*
	63	* Convert from filesystem to in-memory representation.
	64	*/
	65	static struct posix_acl reiserfs_posix_acl_from_disk(const void value, size_t size)
	66	{
	67	const char end = (char )value + size;
	68	int n, count;
	69	struct posix_acl *acl;
	70
	71	if (!value)
	72	return NULL;
	73	if (size < sizeof(reiserfs_acl_header))
	74	return ERR_PTR(-EINVAL);
	75	if (((reiserfs_acl_header *) value)->a_version !=
	76	cpu_to_le32(REISERFS_ACL_VERSION))
	77	return ERR_PTR(-EINVAL);
	78	value = (char *)value + sizeof(reiserfs_acl_header);
	79	count = reiserfs_acl_count(size);
	80	if (count < 0)
	81	return ERR_PTR(-EINVAL);
	82	if (count == 0)
	83	return NULL;
	84	acl = posix_acl_alloc(count, GFP_NOFS);
	85	if (!acl)
	86	return ERR_PTR(-ENOMEM);
	87	for (n = 0; n < count; n++) {
	88	reiserfs_acl_entry entry = (reiserfs_acl_entry ) value;
	89	if ((char *)value + sizeof(reiserfs_acl_entry_short) > end)
	90	goto fail;
	91	acl->a_entries[n].e_tag = le16_to_cpu(entry->e_tag);
	92	acl->a_entries[n].e_perm = le16_to_cpu(entry->e_perm);
	93	switch (acl->a_entries[n].e_tag) {
	94	case ACL_USER_OBJ:
	95	case ACL_GROUP_OBJ:
	96	case ACL_MASK:
	97	case ACL_OTHER:
	98	value = (char *)value +
	99	sizeof(reiserfs_acl_entry_short);
	100	break;
	101
	102	case ACL_USER:
	103	value = (char *)value + sizeof(reiserfs_acl_entry);
	104	if ((char *)value > end)
	105	goto fail;
	106	acl->a_entries[n].e_uid =
	107	make_kuid(&init_user_ns,
	108	le32_to_cpu(entry->e_id));
	109	break;
	110	case ACL_GROUP:
	111	value = (char *)value + sizeof(reiserfs_acl_entry);
	112	if ((char *)value > end)
	113	goto fail;
	114	acl->a_entries[n].e_gid =
	115	make_kgid(&init_user_ns,
	116	le32_to_cpu(entry->e_id));
	117	break;
	118
	119	default:
	120	goto fail;
	121	}
	122	}
	123	if (value != end)
	124	goto fail;
	125	return acl;
	126
	127	fail:
	128	posix_acl_release(acl);
	129	return ERR_PTR(-EINVAL);
	130	}
	131
	132	/*
	133	* Convert from in-memory to filesystem representation.
	134	*/
	135	static void reiserfs_posix_acl_to_disk(const struct posix_acl acl, size_t * size)
	136	{
	137	reiserfs_acl_header *ext_acl;
	138	char *e;
	139	int n;
	140
	141	*size = reiserfs_acl_size(acl->a_count);
	142	ext_acl = kmalloc(sizeof(reiserfs_acl_header) +
	143	acl->a_count *
	144	sizeof(reiserfs_acl_entry),
	145	GFP_NOFS);
	146	if (!ext_acl)
	147	return ERR_PTR(-ENOMEM);
	148	ext_acl->a_version = cpu_to_le32(REISERFS_ACL_VERSION);
	149	e = (char *)ext_acl + sizeof(reiserfs_acl_header);
	150	for (n = 0; n < acl->a_count; n++) {
	151	const struct posix_acl_entry *acl_e = &acl->a_entries[n];
	152	reiserfs_acl_entry entry = (reiserfs_acl_entry ) e;
	153	entry->e_tag = cpu_to_le16(acl->a_entries[n].e_tag);
	154	entry->e_perm = cpu_to_le16(acl->a_entries[n].e_perm);
	155	switch (acl->a_entries[n].e_tag) {
	156	case ACL_USER:
	157	entry->e_id = cpu_to_le32(
	158	from_kuid(&init_user_ns, acl_e->e_uid));
	159	e += sizeof(reiserfs_acl_entry);
	160	break;
	161	case ACL_GROUP:
	162	entry->e_id = cpu_to_le32(
	163	from_kgid(&init_user_ns, acl_e->e_gid));
	164	e += sizeof(reiserfs_acl_entry);
	165	break;
	166
	167	case ACL_USER_OBJ:
	168	case ACL_GROUP_OBJ:
	169	case ACL_MASK:
	170	case ACL_OTHER:
	171	e += sizeof(reiserfs_acl_entry_short);
	172	break;
	173
	174	default:
	175	goto fail;
	176	}
	177	}
	178	return (char *)ext_acl;
	179
	180	fail:
	181	kfree(ext_acl);
	182	return ERR_PTR(-EINVAL);
	183	}
	184
	185	/*
	186	* Inode operation get_posix_acl().
	187	*
	188	* inode->i_mutex: down
	189	* BKL held [before 2.5.x]
	190	*/
	191	struct posix_acl reiserfs_get_acl(struct inode inode, int type)
	192	{
	193	char name, value;
	194	struct posix_acl *acl;
	195	int size;
	196	int retval;
	197
	198	switch (type) {
	199	case ACL_TYPE_ACCESS:
	200	name = XATTR_NAME_POSIX_ACL_ACCESS;
	201	break;
	202	case ACL_TYPE_DEFAULT:
	203	name = XATTR_NAME_POSIX_ACL_DEFAULT;
	204	break;
	205	default:
	206	BUG();
	207	}
	208
	209	size = reiserfs_xattr_get(inode, name, NULL, 0);
	210	if (size < 0) {
	211	if (size == -ENODATA \|\| size == -ENOSYS)
	212	return NULL;
	213	return ERR_PTR(size);
	214	}
	215
	216	value = kmalloc(size, GFP_NOFS);
	217	if (!value)
	218	return ERR_PTR(-ENOMEM);
	219
	220	retval = reiserfs_xattr_get(inode, name, value, size);
	221	if (retval == -ENODATA \|\| retval == -ENOSYS) {
	222	/*
	223	* This shouldn't actually happen as it should have
	224	* been caught above.. but just in case
	225	*/
	226	acl = NULL;
	227	} else if (retval < 0) {
	228	acl = ERR_PTR(retval);
	229	} else {
	230	acl = reiserfs_posix_acl_from_disk(value, retval);
	231	}
	232
	233	kfree(value);
	234	return acl;
	235	}
	236
	237	/*
	238	* Inode operation set_posix_acl().
	239	*
	240	* inode->i_mutex: down
	241	* BKL held [before 2.5.x]
	242	*/
	243	static int
	244	__reiserfs_set_acl(struct reiserfs_transaction_handle th, struct inode inode,
	245	int type, struct posix_acl *acl)
	246	{
	247	char *name;
	248	void *value = NULL;
	249	size_t size = 0;
	250	int error;
	251
	252	switch (type) {
	253	case ACL_TYPE_ACCESS:
	254	name = XATTR_NAME_POSIX_ACL_ACCESS;
	255	break;
	256	case ACL_TYPE_DEFAULT:
	257	name = XATTR_NAME_POSIX_ACL_DEFAULT;
	258	if (!S_ISDIR(inode->i_mode))
	259	return acl ? -EACCES : 0;
	260	break;
	261	default:
	262	return -EINVAL;
	263	}
	264
	265	if (acl) {
	266	value = reiserfs_posix_acl_to_disk(acl, &size);
	267	if (IS_ERR(value))
	268	return (int)PTR_ERR(value);
	269	}
	270
	271	error = reiserfs_xattr_set_handle(th, inode, name, value, size, 0);
	272
	273	/*
	274	* Ensure that the inode gets dirtied if we're only using
	275	* the mode bits and an old ACL didn't exist. We don't need
	276	* to check if the inode is hashed here since we won't get
	277	* called by reiserfs_inherit_default_acl().
	278	*/
	279	if (error == -ENODATA) {
	280	error = 0;
	281	if (type == ACL_TYPE_ACCESS) {
	282	inode->i_ctime = current_time(inode);
	283	mark_inode_dirty(inode);
	284	}
	285	}
	286
	287	kfree(value);
	288
	289	if (!error)
	290	set_cached_acl(inode, type, acl);
	291
	292	return error;
	293	}
	294
	295	/*
	296	* dir->i_mutex: locked,
	297	* inode is new and not released into the wild yet
	298	*/
	299	int
	300	reiserfs_inherit_default_acl(struct reiserfs_transaction_handle *th,
	301	struct inode dir, struct dentry dentry,
	302	struct inode *inode)
	303	{
	304	struct posix_acl default_acl, acl;
	305	int err = 0;
	306
	307	/* ACLs only get applied to files and directories */
	308	if (S_ISLNK(inode->i_mode))
	309	return 0;
	310
	311	/*
	312	* ACLs can only be used on "new" objects, so if it's an old object
	313	* there is nothing to inherit from
	314	*/
	315	if (get_inode_sd_version(dir) == STAT_DATA_V1)
	316	goto apply_umask;
	317
	318	/*
	319	* Don't apply ACLs to objects in the .reiserfs_priv tree.. This
	320	* would be useless since permissions are ignored, and a pain because
	321	* it introduces locking cycles
	322	*/
	323	if (IS_PRIVATE(dir)) {
	324	inode->i_flags \|= S_PRIVATE;
	325	goto apply_umask;
	326	}
	327
	328	err = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl);
	329	if (err)
	330	return err;
	331
	332	if (default_acl) {
	333	err = __reiserfs_set_acl(th, inode, ACL_TYPE_DEFAULT,
	334	default_acl);
	335	posix_acl_release(default_acl);
	336	}
	337	if (acl) {
	338	if (!err)
	339	err = __reiserfs_set_acl(th, inode, ACL_TYPE_ACCESS,
	340	acl);
	341	posix_acl_release(acl);
	342	}
	343
	344	return err;
	345
	346	apply_umask:
	347	/* no ACL, apply umask */
	348	inode->i_mode &= ~current_umask();
	349	return err;
	350	}
	351
	352	/* This is used to cache the default acl before a new object is created.
	353	* The biggest reason for this is to get an idea of how many blocks will
	354	* actually be required for the create operation if we must inherit an ACL.
	355	* An ACL write can add up to 3 object creations and an additional file write
	356	* so we'd prefer not to reserve that many blocks in the journal if we can.
	357	* It also has the advantage of not loading the ACL with a transaction open,
	358	* this may seem silly, but if the owner of the directory is doing the
	359	* creation, the ACL may not be loaded since the permissions wouldn't require
	360	* it.
	361	* We return the number of blocks required for the transaction.
	362	*/
	363	int reiserfs_cache_default_acl(struct inode *inode)
	364	{
	365	struct posix_acl *acl;
	366	int nblocks = 0;
	367
	368	if (IS_PRIVATE(inode))
	369	return 0;
	370
	371	acl = get_acl(inode, ACL_TYPE_DEFAULT);
	372
	373	if (acl && !IS_ERR(acl)) {
	374	int size = reiserfs_acl_size(acl->a_count);
	375
	376	/* Other xattrs can be created during inode creation. We don't
	377	* want to claim too many blocks, so we check to see if we
	378	* we need to create the tree to the xattrs, and then we
	379	* just want two files. */
	380	nblocks = reiserfs_xattr_jcreate_nblocks(inode);
	381	nblocks += JOURNAL_BLOCKS_PER_OBJECT(inode->i_sb);
	382
	383	REISERFS_I(inode)->i_flags \|= i_has_xattr_dir;
	384
	385	/* We need to account for writes + bitmaps for two files */
	386	nblocks += reiserfs_xattr_nblocks(inode, size) * 4;
	387	posix_acl_release(acl);
	388	}
	389
	390	return nblocks;
	391	}
	392
	393	/*
	394	* Called under i_mutex
	395	*/
	396	int reiserfs_acl_chmod(struct inode *inode)
	397	{
	398	if (IS_PRIVATE(inode))
	399	return 0;
	400	if (get_inode_sd_version(inode) == STAT_DATA_V1 \|\|
	401	!reiserfs_posixacl(inode->i_sb))
	402	return 0;
	403
	404	return posix_acl_chmod(inode, inode->i_mode);
	405	}