fs/bcachefs/acl.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0

 #include "bcachefs.h"

 #include "acl.h"
 #include "xattr.h"

 #include <linux/posix_acl.h>

 static const char * const acl_types[] = {
 	[ACL_USER_OBJ]	= "user_obj",
 	[ACL_USER]	= "user",
 	[ACL_GROUP_OBJ]	= "group_obj",
 	[ACL_GROUP]	= "group",
 	[ACL_MASK]	= "mask",
 	[ACL_OTHER]	= "other",
 	NULL,
 };

 void bch2_acl_to_text(struct printbuf *out, const void *value, size_t size)
 {
 	const void *p, *end = value + size;

 	if (!value ||
 	    size < sizeof(bch_acl_header) ||
 	    ((bch_acl_header *)value)->a_version != cpu_to_le32(BCH_ACL_VERSION))
 		return;

 	p = value + sizeof(bch_acl_header);
 	while (p < end) {
 		const bch_acl_entry *in = p;
 		unsigned tag = le16_to_cpu(in->e_tag);

 		prt_str(out, acl_types[tag]);

 		switch (tag) {
 		case ACL_USER_OBJ:
 		case ACL_GROUP_OBJ:
 		case ACL_MASK:
 		case ACL_OTHER:
 			p += sizeof(bch_acl_entry_short);
 			break;
 		case ACL_USER:
 			prt_printf(out, " uid %u", le32_to_cpu(in->e_id));
 			p += sizeof(bch_acl_entry);
 			break;
 		case ACL_GROUP:
 			prt_printf(out, " gid %u", le32_to_cpu(in->e_id));
 			p += sizeof(bch_acl_entry);
 			break;
 		}

 		prt_printf(out, " %o", le16_to_cpu(in->e_perm));

 		if (p != end)
 			prt_char(out, ' ');
 	}
 }

 #ifdef CONFIG_BCACHEFS_POSIX_ACL

 #include "fs.h"

 #include <linux/fs.h>
 #include <linux/posix_acl_xattr.h>
 #include <linux/sched.h>
 #include <linux/slab.h>

 static inline size_t bch2_acl_size(unsigned nr_short, unsigned nr_long)
 {
 	return sizeof(bch_acl_header) +
 		sizeof(bch_acl_entry_short) * nr_short +
 		sizeof(bch_acl_entry) * nr_long;
 }

 static inline int acl_to_xattr_type(int type)
 {
 	switch (type) {
 	case ACL_TYPE_ACCESS:
 		return KEY_TYPE_XATTR_INDEX_POSIX_ACL_ACCESS;
 	case ACL_TYPE_DEFAULT:
 		return KEY_TYPE_XATTR_INDEX_POSIX_ACL_DEFAULT;
 	default:
 		BUG();
 	}
 }

 /*
  * Convert from filesystem to in-memory representation.
  */
 static struct posix_acl *bch2_acl_from_disk(struct btree_trans *trans,
 					    const void *value, size_t size)
 {
 	const void *p, *end = value + size;
 	struct posix_acl *acl;
 	struct posix_acl_entry *out;
 	unsigned count = 0;
 	int ret;

 	if (!value)
 		return NULL;
 	if (size < sizeof(bch_acl_header))
 		goto invalid;
 	if (((bch_acl_header *)value)->a_version !=
 	    cpu_to_le32(BCH_ACL_VERSION))
 		goto invalid;

 	p = value + sizeof(bch_acl_header);
 	while (p < end) {
 		const bch_acl_entry *entry = p;

 		if (p + sizeof(bch_acl_entry_short) > end)
 			goto invalid;

 		switch (le16_to_cpu(entry->e_tag)) {
 		case ACL_USER_OBJ:
 		case ACL_GROUP_OBJ:
 		case ACL_MASK:
 		case ACL_OTHER:
 			p += sizeof(bch_acl_entry_short);
 			break;
 		case ACL_USER:
 		case ACL_GROUP:
 			p += sizeof(bch_acl_entry);
 			break;
 		default:
 			goto invalid;
 		}

 		count++;
 	}

 	if (p > end)
 		goto invalid;

 	if (!count)
 		return NULL;

 	acl = allocate_dropping_locks(trans, ret,
 			posix_acl_alloc(count, _gfp));
 	if (!acl)
 		return ERR_PTR(-ENOMEM);
 	if (ret) {
 		kfree(acl);
 		return ERR_PTR(ret);
 	}

 	out = acl->a_entries;

 	p = value + sizeof(bch_acl_header);
 	while (p < end) {
 		const bch_acl_entry *in = p;

 		out->e_tag  = le16_to_cpu(in->e_tag);
 		out->e_perm = le16_to_cpu(in->e_perm);

 		switch (out->e_tag) {
 		case ACL_USER_OBJ:
 		case ACL_GROUP_OBJ:
 		case ACL_MASK:
 		case ACL_OTHER:
 			p += sizeof(bch_acl_entry_short);
 			break;
 		case ACL_USER:
 			out->e_uid = make_kuid(&init_user_ns,
 					       le32_to_cpu(in->e_id));
 			p += sizeof(bch_acl_entry);
 			break;
 		case ACL_GROUP:
 			out->e_gid = make_kgid(&init_user_ns,
 					       le32_to_cpu(in->e_id));
 			p += sizeof(bch_acl_entry);
 			break;
 		}

 		out++;
 	}

 	BUG_ON(out != acl->a_entries + acl->a_count);

 	return acl;
 invalid:
 	pr_err("invalid acl entry");
 	return ERR_PTR(-EINVAL);
 }

 #define acl_for_each_entry(acl, acl_e)			\
 	for (acl_e = acl->a_entries;			\
 	     acl_e < acl->a_entries + acl->a_count;	\
 	     acl_e++)

 /*
  * Convert from in-memory to filesystem representation.
  */
 static struct bkey_i_xattr *
 bch2_acl_to_xattr(struct btree_trans *trans,
 		  const struct posix_acl *acl,
 		  int type)
 {
 	struct bkey_i_xattr *xattr;
 	bch_acl_header *acl_header;
 	const struct posix_acl_entry *acl_e;
 	void *outptr;
 	unsigned nr_short = 0, nr_long = 0, acl_len, u64s;

 	acl_for_each_entry(acl, acl_e) {
 		switch (acl_e->e_tag) {
 		case ACL_USER:
 		case ACL_GROUP:
 			nr_long++;
 			break;
 		case ACL_USER_OBJ:
 		case ACL_GROUP_OBJ:
 		case ACL_MASK:
 		case ACL_OTHER:
 			nr_short++;
 			break;
 		default:
 			return ERR_PTR(-EINVAL);
 		}
 	}

 	acl_len = bch2_acl_size(nr_short, nr_long);
 	u64s = BKEY_U64s + xattr_val_u64s(0, acl_len);

 	if (u64s > U8_MAX)
 		return ERR_PTR(-E2BIG);

 	xattr = bch2_trans_kmalloc(trans, u64s * sizeof(u64));
 	if (IS_ERR(xattr))
 		return xattr;

 	bkey_xattr_init(&xattr->k_i);
 	xattr->k.u64s		= u64s;
 	xattr->v.x_type		= acl_to_xattr_type(type);
 	xattr->v.x_name_len	= 0;
 	xattr->v.x_val_len	= cpu_to_le16(acl_len);

 	acl_header = xattr_val(&xattr->v);
 	acl_header->a_version = cpu_to_le32(BCH_ACL_VERSION);

 	outptr = (void *) acl_header + sizeof(*acl_header);

 	acl_for_each_entry(acl, acl_e) {
 		bch_acl_entry *entry = outptr;

 		entry->e_tag = cpu_to_le16(acl_e->e_tag);
 		entry->e_perm = cpu_to_le16(acl_e->e_perm);
 		switch (acl_e->e_tag) {
 		case ACL_USER:
 			entry->e_id = cpu_to_le32(
 				from_kuid(&init_user_ns, acl_e->e_uid));
 			outptr += sizeof(bch_acl_entry);
 			break;
 		case ACL_GROUP:
 			entry->e_id = cpu_to_le32(
 				from_kgid(&init_user_ns, acl_e->e_gid));
 			outptr += sizeof(bch_acl_entry);
 			break;

 		case ACL_USER_OBJ:
 		case ACL_GROUP_OBJ:
 		case ACL_MASK:
 		case ACL_OTHER:
 			outptr += sizeof(bch_acl_entry_short);
 			break;
 		}
 	}

 	BUG_ON(outptr != xattr_val(&xattr->v) + acl_len);

 	return xattr;
 }

 struct posix_acl *bch2_get_acl(struct mnt_idmap *idmap,
 			       struct dentry *dentry, int type)
 {
 	struct bch_inode_info *inode = to_bch_ei(dentry->d_inode);
 	struct bch_fs *c = inode->v.i_sb->s_fs_info;
 	struct bch_hash_info hash = bch2_hash_info_init(c, &inode->ei_inode);
 	struct xattr_search_key search = X_SEARCH(acl_to_xattr_type(type), "", 0);
 	struct btree_trans *trans = bch2_trans_get(c);
 	struct btree_iter iter = { NULL };
 	struct posix_acl *acl = NULL;
 retry:
 	bch2_trans_begin(trans);

 	struct bkey_s_c k = bch2_hash_lookup(trans, &iter, bch2_xattr_hash_desc,
 					     &hash, inode_inum(inode), &search, 0);
 	int ret = bkey_err(k);
 	if (ret)
 		goto err;

 	struct bkey_s_c_xattr xattr = bkey_s_c_to_xattr(k);
 	acl = bch2_acl_from_disk(trans, xattr_val(xattr.v),
 				 le16_to_cpu(xattr.v->x_val_len));
 	ret = PTR_ERR_OR_ZERO(acl);
 err:
 	if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
 		goto retry;

 	if (ret)
 		acl = !bch2_err_matches(ret, ENOENT) ? ERR_PTR(ret) : NULL;

 	if (!IS_ERR_OR_NULL(acl))
 		set_cached_acl(&inode->v, type, acl);

 	bch2_trans_iter_exit(trans, &iter);
 	bch2_trans_put(trans);
 	return acl;
 }

 int bch2_set_acl_trans(struct btree_trans *trans, subvol_inum inum,
 		       struct bch_inode_unpacked *inode_u,
 		       struct posix_acl *acl, int type)
 {
 	struct bch_hash_info hash_info = bch2_hash_info_init(trans->c, inode_u);
 	int ret;

 	if (type == ACL_TYPE_DEFAULT &&
 	    !S_ISDIR(inode_u->bi_mode))
 		return acl ? -EACCES : 0;

 	if (acl) {
 		struct bkey_i_xattr *xattr =
 			bch2_acl_to_xattr(trans, acl, type);
 		if (IS_ERR(xattr))
 			return PTR_ERR(xattr);

 		ret = bch2_hash_set(trans, bch2_xattr_hash_desc, &hash_info,
 				    inum, &xattr->k_i, 0);
 	} else {
 		struct xattr_search_key search =
 			X_SEARCH(acl_to_xattr_type(type), "", 0);

 		ret = bch2_hash_delete(trans, bch2_xattr_hash_desc, &hash_info,
 				       inum, &search);
 	}

 	return bch2_err_matches(ret, ENOENT) ? 0 : ret;
 }

 int bch2_set_acl(struct mnt_idmap *idmap,
 		 struct dentry *dentry,
 		 struct posix_acl *_acl, int type)
 {
 	struct bch_inode_info *inode = to_bch_ei(dentry->d_inode);
 	struct bch_fs *c = inode->v.i_sb->s_fs_info;
 	struct btree_iter inode_iter = { NULL };
 	struct bch_inode_unpacked inode_u;
 	struct posix_acl *acl;
 	umode_t mode;
 	int ret;

 	mutex_lock(&inode->ei_update_lock);
 	struct btree_trans *trans = bch2_trans_get(c);
 retry:
 	bch2_trans_begin(trans);
 	acl = _acl;

 	ret   = bch2_subvol_is_ro_trans(trans, inode->ei_subvol) ?:
 		bch2_inode_peek(trans, &inode_iter, &inode_u, inode_inum(inode),
 			      BTREE_ITER_intent);
 	if (ret)
 		goto btree_err;

 	mode = inode_u.bi_mode;

 	if (type == ACL_TYPE_ACCESS) {
 		ret = posix_acl_update_mode(idmap, &inode->v, &mode, &acl);
 		if (ret)
 			goto btree_err;
 	}

 	ret = bch2_set_acl_trans(trans, inode_inum(inode), &inode_u, acl, type);
 	if (ret)
 		goto btree_err;

 	inode_u.bi_ctime	= bch2_current_time(c);
 	inode_u.bi_mode		= mode;

 	ret =   bch2_inode_write(trans, &inode_iter, &inode_u) ?:
 		bch2_trans_commit(trans, NULL, NULL, 0);
 btree_err:
 	bch2_trans_iter_exit(trans, &inode_iter);

 	if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
 		goto retry;
 	if (unlikely(ret))
 		goto err;

 	bch2_inode_update_after_write(trans, inode, &inode_u,
 				      ATTR_CTIME|ATTR_MODE);

 	set_cached_acl(&inode->v, type, acl);
 err:
 	bch2_trans_put(trans);
 	mutex_unlock(&inode->ei_update_lock);

 	return ret;
 }

 int bch2_acl_chmod(struct btree_trans *trans, subvol_inum inum,
 		   struct bch_inode_unpacked *inode,
 		   umode_t mode,
 		   struct posix_acl **new_acl)
 {
 	struct bch_hash_info hash_info = bch2_hash_info_init(trans->c, inode);
 	struct xattr_search_key search = X_SEARCH(KEY_TYPE_XATTR_INDEX_POSIX_ACL_ACCESS, "", 0);
 	struct btree_iter iter;
 	struct posix_acl *acl = NULL;

 	struct bkey_s_c k = bch2_hash_lookup(trans, &iter, bch2_xattr_hash_desc,
 			       &hash_info, inum, &search, BTREE_ITER_intent);
 	int ret = bkey_err(k);
 	if (ret)
 		return bch2_err_matches(ret, ENOENT) ? 0 : ret;

 	struct bkey_s_c_xattr xattr = bkey_s_c_to_xattr(k);

 	acl = bch2_acl_from_disk(trans, xattr_val(xattr.v),
 			le16_to_cpu(xattr.v->x_val_len));
 	ret = PTR_ERR_OR_ZERO(acl);
 	if (ret)
 		goto err;

 	ret = allocate_dropping_locks_errcode(trans, __posix_acl_chmod(&acl, _gfp, mode));
 	if (ret)
 		goto err;

 	struct bkey_i_xattr *new = bch2_acl_to_xattr(trans, acl, ACL_TYPE_ACCESS);
 	ret = PTR_ERR_OR_ZERO(new);
 	if (ret)
 		goto err;

 	new->k.p = iter.pos;
 	ret = bch2_trans_update(trans, &iter, &new->k_i, 0);
 	*new_acl = acl;
 	acl = NULL;
 err:
 	bch2_trans_iter_exit(trans, &iter);
 	if (!IS_ERR_OR_NULL(acl))
 		kfree(acl);
 	return ret;
 }

 #endif /* CONFIG_BCACHEFS_POSIX_ACL */
	// SPDX-License-Identifier: GPL-2.0

	#include "bcachefs.h"

	#include "acl.h"
	#include "xattr.h"

	#include <linux/posix_acl.h>

	static const char * const acl_types[] = {
	[ACL_USER_OBJ] = "user_obj",
	[ACL_USER] = "user",
	[ACL_GROUP_OBJ] = "group_obj",
	[ACL_GROUP] = "group",
	[ACL_MASK] = "mask",
	[ACL_OTHER] = "other",
	NULL,
	};

	void bch2_acl_to_text(struct printbuf out, const void value, size_t size)
	{
	const void p, end = value + size;

	if (!value \|\|
	size < sizeof(bch_acl_header) \|\|
	((bch_acl_header *)value)->a_version != cpu_to_le32(BCH_ACL_VERSION))
	return;

	p = value + sizeof(bch_acl_header);
	while (p < end) {
	const bch_acl_entry *in = p;
	unsigned tag = le16_to_cpu(in->e_tag);

	prt_str(out, acl_types[tag]);

	switch (tag) {
	case ACL_USER_OBJ:
	case ACL_GROUP_OBJ:
	case ACL_MASK:
	case ACL_OTHER:
	p += sizeof(bch_acl_entry_short);
	break;
	case ACL_USER:
	prt_printf(out, " uid %u", le32_to_cpu(in->e_id));
	p += sizeof(bch_acl_entry);
	break;
	case ACL_GROUP:
	prt_printf(out, " gid %u", le32_to_cpu(in->e_id));
	p += sizeof(bch_acl_entry);
	break;
	}

	prt_printf(out, " %o", le16_to_cpu(in->e_perm));

	if (p != end)
	prt_char(out, ' ');
	}
	}

	#ifdef CONFIG_BCACHEFS_POSIX_ACL

	#include "fs.h"

	#include <linux/fs.h>
	#include <linux/posix_acl_xattr.h>
	#include <linux/sched.h>
	#include <linux/slab.h>

	static inline size_t bch2_acl_size(unsigned nr_short, unsigned nr_long)
	{
	return sizeof(bch_acl_header) +
	sizeof(bch_acl_entry_short) * nr_short +
	sizeof(bch_acl_entry) * nr_long;
	}

	static inline int acl_to_xattr_type(int type)
	{
	switch (type) {
	case ACL_TYPE_ACCESS:
	return KEY_TYPE_XATTR_INDEX_POSIX_ACL_ACCESS;
	case ACL_TYPE_DEFAULT:
	return KEY_TYPE_XATTR_INDEX_POSIX_ACL_DEFAULT;
	default:
	BUG();
	}
	}

	/*
	* Convert from filesystem to in-memory representation.
	*/
	static struct posix_acl bch2_acl_from_disk(struct btree_trans trans,
	const void *value, size_t size)
	{
	const void p, end = value + size;
	struct posix_acl *acl;
	struct posix_acl_entry *out;
	unsigned count = 0;
	int ret;

	if (!value)
	return NULL;
	if (size < sizeof(bch_acl_header))
	goto invalid;
	if (((bch_acl_header *)value)->a_version !=
	cpu_to_le32(BCH_ACL_VERSION))
	goto invalid;

	p = value + sizeof(bch_acl_header);
	while (p < end) {
	const bch_acl_entry *entry = p;

	if (p + sizeof(bch_acl_entry_short) > end)
	goto invalid;

	switch (le16_to_cpu(entry->e_tag)) {
	case ACL_USER_OBJ:
	case ACL_GROUP_OBJ:
	case ACL_MASK:
	case ACL_OTHER:
	p += sizeof(bch_acl_entry_short);
	break;
	case ACL_USER:
	case ACL_GROUP:
	p += sizeof(bch_acl_entry);
	break;
	default:
	goto invalid;
	}

	count++;
	}

	if (p > end)
	goto invalid;

	if (!count)
	return NULL;

	acl = allocate_dropping_locks(trans, ret,
	posix_acl_alloc(count, _gfp));
	if (!acl)
	return ERR_PTR(-ENOMEM);
	if (ret) {
	kfree(acl);
	return ERR_PTR(ret);
	}

	out = acl->a_entries;

	p = value + sizeof(bch_acl_header);
	while (p < end) {
	const bch_acl_entry *in = p;

	out->e_tag = le16_to_cpu(in->e_tag);
	out->e_perm = le16_to_cpu(in->e_perm);

	switch (out->e_tag) {
	case ACL_USER_OBJ:
	case ACL_GROUP_OBJ:
	case ACL_MASK:
	case ACL_OTHER:
	p += sizeof(bch_acl_entry_short);
	break;
	case ACL_USER:
	out->e_uid = make_kuid(&init_user_ns,
	le32_to_cpu(in->e_id));
	p += sizeof(bch_acl_entry);
	break;
	case ACL_GROUP:
	out->e_gid = make_kgid(&init_user_ns,
	le32_to_cpu(in->e_id));
	p += sizeof(bch_acl_entry);
	break;
	}

	out++;
	}

	BUG_ON(out != acl->a_entries + acl->a_count);

	return acl;
	invalid:
	pr_err("invalid acl entry");
	return ERR_PTR(-EINVAL);
	}

	#define acl_for_each_entry(acl, acl_e) \
	for (acl_e = acl->a_entries; \
	acl_e < acl->a_entries + acl->a_count; \
	acl_e++)

	/*
	* Convert from in-memory to filesystem representation.
	*/
	static struct bkey_i_xattr *
	bch2_acl_to_xattr(struct btree_trans *trans,
	const struct posix_acl *acl,
	int type)
	{
	struct bkey_i_xattr *xattr;
	bch_acl_header *acl_header;
	const struct posix_acl_entry *acl_e;
	void *outptr;
	unsigned nr_short = 0, nr_long = 0, acl_len, u64s;

	acl_for_each_entry(acl, acl_e) {
	switch (acl_e->e_tag) {
	case ACL_USER:
	case ACL_GROUP:
	nr_long++;
	break;
	case ACL_USER_OBJ:
	case ACL_GROUP_OBJ:
	case ACL_MASK:
	case ACL_OTHER:
	nr_short++;
	break;
	default:
	return ERR_PTR(-EINVAL);
	}
	}

	acl_len = bch2_acl_size(nr_short, nr_long);
	u64s = BKEY_U64s + xattr_val_u64s(0, acl_len);

	if (u64s > U8_MAX)
	return ERR_PTR(-E2BIG);

	xattr = bch2_trans_kmalloc(trans, u64s * sizeof(u64));
	if (IS_ERR(xattr))
	return xattr;

	bkey_xattr_init(&xattr->k_i);
	xattr->k.u64s = u64s;
	xattr->v.x_type = acl_to_xattr_type(type);
	xattr->v.x_name_len = 0;
	xattr->v.x_val_len = cpu_to_le16(acl_len);

	acl_header = xattr_val(&xattr->v);
	acl_header->a_version = cpu_to_le32(BCH_ACL_VERSION);

	outptr = (void ) acl_header + sizeof(acl_header);

	acl_for_each_entry(acl, acl_e) {
	bch_acl_entry *entry = outptr;

	entry->e_tag = cpu_to_le16(acl_e->e_tag);
	entry->e_perm = cpu_to_le16(acl_e->e_perm);
	switch (acl_e->e_tag) {
	case ACL_USER:
	entry->e_id = cpu_to_le32(
	from_kuid(&init_user_ns, acl_e->e_uid));
	outptr += sizeof(bch_acl_entry);
	break;
	case ACL_GROUP:
	entry->e_id = cpu_to_le32(
	from_kgid(&init_user_ns, acl_e->e_gid));
	outptr += sizeof(bch_acl_entry);
	break;

	case ACL_USER_OBJ:
	case ACL_GROUP_OBJ:
	case ACL_MASK:
	case ACL_OTHER:
	outptr += sizeof(bch_acl_entry_short);
	break;
	}
	}

	BUG_ON(outptr != xattr_val(&xattr->v) + acl_len);

	return xattr;
	}

	struct posix_acl bch2_get_acl(struct mnt_idmap idmap,
	struct dentry *dentry, int type)
	{
	struct bch_inode_info *inode = to_bch_ei(dentry->d_inode);
	struct bch_fs *c = inode->v.i_sb->s_fs_info;
	struct bch_hash_info hash = bch2_hash_info_init(c, &inode->ei_inode);
	struct xattr_search_key search = X_SEARCH(acl_to_xattr_type(type), "", 0);
	struct btree_trans *trans = bch2_trans_get(c);
	struct btree_iter iter = { NULL };
	struct posix_acl *acl = NULL;
	retry:
	bch2_trans_begin(trans);

	struct bkey_s_c k = bch2_hash_lookup(trans, &iter, bch2_xattr_hash_desc,
	&hash, inode_inum(inode), &search, 0);
	int ret = bkey_err(k);
	if (ret)
	goto err;

	struct bkey_s_c_xattr xattr = bkey_s_c_to_xattr(k);
	acl = bch2_acl_from_disk(trans, xattr_val(xattr.v),
	le16_to_cpu(xattr.v->x_val_len));
	ret = PTR_ERR_OR_ZERO(acl);
	err:
	if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
	goto retry;

	if (ret)
	acl = !bch2_err_matches(ret, ENOENT) ? ERR_PTR(ret) : NULL;

	if (!IS_ERR_OR_NULL(acl))
	set_cached_acl(&inode->v, type, acl);

	bch2_trans_iter_exit(trans, &iter);
	bch2_trans_put(trans);
	return acl;
	}

	int bch2_set_acl_trans(struct btree_trans *trans, subvol_inum inum,
	struct bch_inode_unpacked *inode_u,
	struct posix_acl *acl, int type)
	{
	struct bch_hash_info hash_info = bch2_hash_info_init(trans->c, inode_u);
	int ret;

	if (type == ACL_TYPE_DEFAULT &&
	!S_ISDIR(inode_u->bi_mode))
	return acl ? -EACCES : 0;

	if (acl) {
	struct bkey_i_xattr *xattr =
	bch2_acl_to_xattr(trans, acl, type);
	if (IS_ERR(xattr))
	return PTR_ERR(xattr);

	ret = bch2_hash_set(trans, bch2_xattr_hash_desc, &hash_info,
	inum, &xattr->k_i, 0);
	} else {
	struct xattr_search_key search =
	X_SEARCH(acl_to_xattr_type(type), "", 0);

	ret = bch2_hash_delete(trans, bch2_xattr_hash_desc, &hash_info,
	inum, &search);
	}

	return bch2_err_matches(ret, ENOENT) ? 0 : ret;
	}

	int bch2_set_acl(struct mnt_idmap *idmap,
	struct dentry *dentry,
	struct posix_acl *_acl, int type)
	{
	struct bch_inode_info *inode = to_bch_ei(dentry->d_inode);
	struct bch_fs *c = inode->v.i_sb->s_fs_info;
	struct btree_iter inode_iter = { NULL };
	struct bch_inode_unpacked inode_u;
	struct posix_acl *acl;
	umode_t mode;
	int ret;

	mutex_lock(&inode->ei_update_lock);
	struct btree_trans *trans = bch2_trans_get(c);
	retry:
	bch2_trans_begin(trans);
	acl = _acl;

	ret = bch2_subvol_is_ro_trans(trans, inode->ei_subvol) ?:
	bch2_inode_peek(trans, &inode_iter, &inode_u, inode_inum(inode),
	BTREE_ITER_intent);
	if (ret)
	goto btree_err;

	mode = inode_u.bi_mode;

	if (type == ACL_TYPE_ACCESS) {
	ret = posix_acl_update_mode(idmap, &inode->v, &mode, &acl);
	if (ret)
	goto btree_err;
	}

	ret = bch2_set_acl_trans(trans, inode_inum(inode), &inode_u, acl, type);
	if (ret)
	goto btree_err;

	inode_u.bi_ctime = bch2_current_time(c);
	inode_u.bi_mode = mode;

	ret = bch2_inode_write(trans, &inode_iter, &inode_u) ?:
	bch2_trans_commit(trans, NULL, NULL, 0);
	btree_err:
	bch2_trans_iter_exit(trans, &inode_iter);

	if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
	goto retry;
	if (unlikely(ret))
	goto err;

	bch2_inode_update_after_write(trans, inode, &inode_u,
	ATTR_CTIME\|ATTR_MODE);

	set_cached_acl(&inode->v, type, acl);
	err:
	bch2_trans_put(trans);
	mutex_unlock(&inode->ei_update_lock);

	return ret;
	}

	int bch2_acl_chmod(struct btree_trans *trans, subvol_inum inum,
	struct bch_inode_unpacked *inode,
	umode_t mode,
	struct posix_acl **new_acl)
	{
	struct bch_hash_info hash_info = bch2_hash_info_init(trans->c, inode);
	struct xattr_search_key search = X_SEARCH(KEY_TYPE_XATTR_INDEX_POSIX_ACL_ACCESS, "", 0);
	struct btree_iter iter;
	struct posix_acl *acl = NULL;

	struct bkey_s_c k = bch2_hash_lookup(trans, &iter, bch2_xattr_hash_desc,
	&hash_info, inum, &search, BTREE_ITER_intent);
	int ret = bkey_err(k);
	if (ret)
	return bch2_err_matches(ret, ENOENT) ? 0 : ret;

	struct bkey_s_c_xattr xattr = bkey_s_c_to_xattr(k);

	acl = bch2_acl_from_disk(trans, xattr_val(xattr.v),
	le16_to_cpu(xattr.v->x_val_len));
	ret = PTR_ERR_OR_ZERO(acl);
	if (ret)
	goto err;

	ret = allocate_dropping_locks_errcode(trans, __posix_acl_chmod(&acl, _gfp, mode));
	if (ret)
	goto err;

	struct bkey_i_xattr *new = bch2_acl_to_xattr(trans, acl, ACL_TYPE_ACCESS);
	ret = PTR_ERR_OR_ZERO(new);
	if (ret)
	goto err;

	new->k.p = iter.pos;
	ret = bch2_trans_update(trans, &iter, &new->k_i, 0);
	*new_acl = acl;
	acl = NULL;
	err:
	bch2_trans_iter_exit(trans, &iter);
	if (!IS_ERR_OR_NULL(acl))
	kfree(acl);
	return ret;
	}

	#endif /* CONFIG_BCACHEFS_POSIX_ACL */