Merge branch 'Refactor cgroup_bpf internals to use more specific attach_type'

Dave Marchevsky says:

====================

The cgroup_bpf struct has a few arrays (effective, progs, and flags) of
size MAX_BPF_ATTACH_TYPE. These are meant to separate progs by their
attach type, currently represented by the bpf_attach_type enum.

There are some bpf_attach_type values which are not valid attach types
for cgroup bpf programs. Programs with these attach types will never be
handled by cgroup_bpf_{attach,detach} and thus will never be held in
cgroup_bpf structs. Even if such programs did make it into their
reserved slot in those arrays, they would never be executed.

Accordingly we can migrate to a new internal cgroup_bpf-specific enum
for these arrays, saving some bytes per cgroup and making it more
obvious which BPF programs belong there. netns_bpf_attach_type is an
existing example of this pattern, let's do similar for cgroup_bpf.

v1->v2: Address Daniel's comments
	* Reverse xmas tree ordering for def changes
	* Helper macro to reduce to_cgroup_bpf_attach_type boilerplate
		* checkpatch.pl complains: "ERROR: Macros with complex values should
		be enclosed in parentheses". Found some existing macros (do 'git grep
		"define case"') which get same complaint. Think it's fine to keep
		as-is since it's immediately undef'd.
	* Remove CG_BPF_ prefix from cgroup_bpf_attach_type
		* Although I agree that the prefix is redundant, the de-prefixed
		names feel a bit too 'general' given the internal use of the enum.
		e.g. when someone sees CGROUP_INET6_BIND it's not obvious that it
		should only be used in certain ways internally.
		* Don't feel strongly about this, just my thoughts as a noob to the
		internals.
	* Rebase onto latest bpf-next/master
		* No significant conflicts, some small boilerplate adjustments
		needed to catch up to Andrii's "bpf: Refactor BPF_PROG_RUN_ARRAY
		family of macros into functions" change
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

include/uapi/linux/bpf.h

@@ -84,7 +84,7 @@ struct bpf_lpm_trie_key {
 
 struct bpf_cgroup_storage_key {
 	__u64	cgroup_inode_id;	/* cgroup inode id */
-	__u32	attach_type;		/* program attach type */
+	__u32	attach_type;		/* program attach type (enum bpf_attach_type) */
 };
 
 union bpf_iter_link_info {

net/ipv4/af_inet.c

@@ -452,7 +452,7 @@ int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 	 * changes context in a wrong way it will be caught.
 	 */
 	err = BPF_CGROUP_RUN_PROG_INET_BIND_LOCK(sk, uaddr,
-						 BPF_CGROUP_INET4_BIND, &flags);
+						 CGROUP_INET4_BIND, &flags);
 	if (err)
 		return err;
 
@@ -781,7 +781,7 @@ int inet_getname(struct socket *sock, struct sockaddr *uaddr,
 		sin->sin_port = inet->inet_dport;
 		sin->sin_addr.s_addr = inet->inet_daddr;
 		BPF_CGROUP_RUN_SA_PROG_LOCK(sk, (struct sockaddr *)sin,
-					    BPF_CGROUP_INET4_GETPEERNAME,
+					    CGROUP_INET4_GETPEERNAME,
 					    NULL);
 	} else {
 		__be32 addr = inet->inet_rcv_saddr;
@@ -790,7 +790,7 @@ int inet_getname(struct socket *sock, struct sockaddr *uaddr,
 		sin->sin_port = inet->inet_sport;
 		sin->sin_addr.s_addr = addr;
 		BPF_CGROUP_RUN_SA_PROG_LOCK(sk, (struct sockaddr *)sin,
-					    BPF_CGROUP_INET4_GETSOCKNAME,
+					    CGROUP_INET4_GETSOCKNAME,
 					    NULL);
 	}
 	memset(sin->sin_zero, 0, sizeof(sin->sin_zero));

net/ipv4/udp.c

@@ -1143,7 +1143,7 @@ int udp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 		rcu_read_unlock();
 	}
 
-	if (cgroup_bpf_enabled(BPF_CGROUP_UDP4_SENDMSG) && !connected) {
+	if (cgroup_bpf_enabled(CGROUP_UDP4_SENDMSG) && !connected) {
 		err = BPF_CGROUP_RUN_PROG_UDP4_SENDMSG_LOCK(sk,
 					    (struct sockaddr *)usin, &ipc.addr);
 		if (err)

net/ipv6/af_inet6.c

@@ -455,7 +455,7 @@ int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 	 * changes context in a wrong way it will be caught.
 	 */
 	err = BPF_CGROUP_RUN_PROG_INET_BIND_LOCK(sk, uaddr,
-						 BPF_CGROUP_INET6_BIND, &flags);
+						 CGROUP_INET6_BIND, &flags);
 	if (err)
 		return err;
 
@@ -532,7 +532,7 @@ int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
 		if (np->sndflow)
 			sin->sin6_flowinfo = np->flow_label;
 		BPF_CGROUP_RUN_SA_PROG_LOCK(sk, (struct sockaddr *)sin,
-					    BPF_CGROUP_INET6_GETPEERNAME,
+					    CGROUP_INET6_GETPEERNAME,
 					    NULL);
 	} else {
 		if (ipv6_addr_any(&sk->sk_v6_rcv_saddr))
@@ -541,7 +541,7 @@ int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
 			sin->sin6_addr = sk->sk_v6_rcv_saddr;
 		sin->sin6_port = inet->inet_sport;
 		BPF_CGROUP_RUN_SA_PROG_LOCK(sk, (struct sockaddr *)sin,
-					    BPF_CGROUP_INET6_GETSOCKNAME,
+					    CGROUP_INET6_GETSOCKNAME,
 					    NULL);
 	}
 	sin->sin6_scope_id = ipv6_iface_scope_id(&sin->sin6_addr,

net/ipv6/udp.c

@@ -1475,7 +1475,7 @@ int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 		fl6.saddr = np->saddr;
 	fl6.fl6_sport = inet->inet_sport;
 
-	if (cgroup_bpf_enabled(BPF_CGROUP_UDP6_SENDMSG) && !connected) {
+	if (cgroup_bpf_enabled(CGROUP_UDP6_SENDMSG) && !connected) {
 		err = BPF_CGROUP_RUN_PROG_UDP6_SENDMSG_LOCK(sk,
 					   (struct sockaddr *)sin6, &fl6.saddr);
 		if (err)

tools/include/uapi/linux/bpf.h

@@ -84,7 +84,7 @@ struct bpf_lpm_trie_key {
 
 struct bpf_cgroup_storage_key {
 	__u64	cgroup_inode_id;	/* cgroup inode id */
-	__u32	attach_type;		/* program attach type */
+	__u32	attach_type;		/* program attach type (enum bpf_attach_type) */
 };
 
 union bpf_iter_link_info {