/* 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;
}
/*
 * 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++) {
		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);
}
Example #3
0
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));
		int depth;

		depth = reiserfs_write_lock_once(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_once(inode->i_sb, depth);
	}
	posix_acl_release(clone);
	return error;
}