Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
[cris-mirror.git] / drivers / block / drbd / drbd_nla.c
blob8e261cb5198bd1ab03f4926ccb0ebc35da766d67
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/kernel.h>
3 #include <net/netlink.h>
4 #include <linux/drbd_genl_api.h>
5 #include "drbd_nla.h"
7 static int drbd_nla_check_mandatory(int maxtype, struct nlattr *nla)
9 struct nlattr *head = nla_data(nla);
10 int len = nla_len(nla);
11 int rem;
14 * validate_nla (called from nla_parse_nested) ignores attributes
15 * beyond maxtype, and does not understand the DRBD_GENLA_F_MANDATORY flag.
16 * In order to have it validate attributes with the DRBD_GENLA_F_MANDATORY
17 * flag set also, check and remove that flag before calling
18 * nla_parse_nested.
21 nla_for_each_attr(nla, head, len, rem) {
22 if (nla->nla_type & DRBD_GENLA_F_MANDATORY) {
23 nla->nla_type &= ~DRBD_GENLA_F_MANDATORY;
24 if (nla_type(nla) > maxtype)
25 return -EOPNOTSUPP;
28 return 0;
31 int drbd_nla_parse_nested(struct nlattr *tb[], int maxtype, struct nlattr *nla,
32 const struct nla_policy *policy)
34 int err;
36 err = drbd_nla_check_mandatory(maxtype, nla);
37 if (!err)
38 err = nla_parse_nested(tb, maxtype, nla, policy, NULL);
40 return err;
43 struct nlattr *drbd_nla_find_nested(int maxtype, struct nlattr *nla, int attrtype)
45 int err;
47 * If any nested attribute has the DRBD_GENLA_F_MANDATORY flag set and
48 * we don't know about that attribute, reject all the nested
49 * attributes.
51 err = drbd_nla_check_mandatory(maxtype, nla);
52 if (err)
53 return ERR_PTR(err);
54 return nla_find_nested(nla, attrtype);