quota/genetlink: use proper genetlink multicast APIs

[~andy/linux] / net / netlink / genetlink.c

diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c
index 353909d46dda86d810bb00248de49bdd1ab0acbd..bee91a7527a58ae002b5464471f14b93f875e511 100644 (file)
--- a/net/netlink/genetlink.c
+++ b/net/netlink/genetlink.c
@@ -69,8 +69,11 @@ static struct list_head family_ht[GENL_FAM_TAB_SIZE];
  * abuses the API and thinks it can statically use group 1.
  * That group will typically conflict with other groups that
  * any proper users use.
+ * Bit 17 is marked as already used since the VFS quota code
+ * also abused this API and relied on family == group ID, we
+ * cater to that by giving it a static family and group ID.
  */
-static unsigned long mc_group_start = 0x3;
+static unsigned long mc_group_start = 0x3 | BIT(GENL_ID_VFS_DQUOT);
 static unsigned long *mc_groups = &mc_group_start;
 static unsigned long mc_groups_longs = 1;
 
@@ -130,7 +133,8 @@ static u16 genl_generate_id(void)
        int i;
 
        for (i = 0; i <= GENL_MAX_ID - GENL_MIN_ID; i++) {
-               if (!genl_family_find_byid(id_gen_idx))
+               if (id_gen_idx != GENL_ID_VFS_DQUOT &&
+                   !genl_family_find_byid(id_gen_idx))
                        return id_gen_idx;
                if (++id_gen_idx > GENL_MAX_ID)
                        id_gen_idx = GENL_MIN_ID;
@@ -169,6 +173,8 @@ int genl_register_mc_group(struct genl_family *family,
                id = GENL_ID_CTRL;
        else if (strcmp(family->name, "NET_DM") == 0)
                id = 1;
+       else if (strcmp(family->name, "VFS_DQUOT") == 0)
+               id = GENL_ID_VFS_DQUOT;
        else
                id = find_first_zero_bit(mc_groups,
                                         mc_groups_longs * BITS_PER_LONG);