bpf: Sync bpf.h to tools/

Sync BPF_PROG_TYPE_CGROUP_SYSCTL related bpf UAPI changes to tools/.

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 2e96d0b..89976de 100644 (file)
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -167,6 +167,7 @@ enum bpf_prog_type {
        BPF_PROG_TYPE_LIRC_MODE2,
        BPF_PROG_TYPE_SK_REUSEPORT,
        BPF_PROG_TYPE_FLOW_DISSECTOR,
+       BPF_PROG_TYPE_CGROUP_SYSCTL,
 };
 
 enum bpf_attach_type {
@@ -188,6 +189,7 @@ enum bpf_attach_type {
        BPF_CGROUP_UDP6_SENDMSG,
        BPF_LIRC_MODE2,
        BPF_FLOW_DISSECTOR,
+       BPF_CGROUP_SYSCTL,
        __MAX_BPF_ATTACH_TYPE
 };
 
@@ -2504,6 +2506,75 @@ union bpf_attr {
  *     Return
  *             0 if iph and th are a valid SYN cookie ACK, or a negative error
  *             otherwise.
+ *
+ * int bpf_sysctl_get_name(struct bpf_sysctl *ctx, char *buf, size_t buf_len, u64 flags)
+ *     Description
+ *             Get name of sysctl in /proc/sys/ and copy it into provided by
+ *             program buffer *buf* of size *buf_len*.
+ *
+ *             The buffer is always NUL terminated, unless it's zero-sized.
+ *
+ *             If *flags* is zero, full name (e.g. "net/ipv4/tcp_mem") is
+ *             copied. Use **BPF_F_SYSCTL_BASE_NAME** flag to copy base name
+ *             only (e.g. "tcp_mem").
+ *     Return
+ *             Number of character copied (not including the trailing NUL).
+ *
+ *             **-E2BIG** if the buffer wasn't big enough (*buf* will contain
+ *             truncated name in this case).
+ *
+ * int bpf_sysctl_get_current_value(struct bpf_sysctl *ctx, char *buf, size_t buf_len)
+ *     Description
+ *             Get current value of sysctl as it is presented in /proc/sys
+ *             (incl. newline, etc), and copy it as a string into provided
+ *             by program buffer *buf* of size *buf_len*.
+ *
+ *             The whole value is copied, no matter what file position user
+ *             space issued e.g. sys_read at.
+ *
+ *             The buffer is always NUL terminated, unless it's zero-sized.
+ *     Return
+ *             Number of character copied (not including the trailing NUL).
+ *
+ *             **-E2BIG** if the buffer wasn't big enough (*buf* will contain
+ *             truncated name in this case).
+ *
+ *             **-EINVAL** if current value was unavailable, e.g. because
+ *             sysctl is uninitialized and read returns -EIO for it.
+ *
+ * int bpf_sysctl_get_new_value(struct bpf_sysctl *ctx, char *buf, size_t buf_len)
+ *     Description
+ *             Get new value being written by user space to sysctl (before
+ *             the actual write happens) and copy it as a string into
+ *             provided by program buffer *buf* of size *buf_len*.
+ *
+ *             User space may write new value at file position > 0.
+ *
+ *             The buffer is always NUL terminated, unless it's zero-sized.
+ *     Return
+ *             Number of character copied (not including the trailing NUL).
+ *
+ *             **-E2BIG** if the buffer wasn't big enough (*buf* will contain
+ *             truncated name in this case).
+ *
+ *             **-EINVAL** if sysctl is being read.
+ *
+ * int bpf_sysctl_set_new_value(struct bpf_sysctl *ctx, const char *buf, size_t buf_len)
+ *     Description
+ *             Override new value being written by user space to sysctl with
+ *             value provided by program in buffer *buf* of size *buf_len*.
+ *
+ *             *buf* should contain a string in same form as provided by user
+ *             space on sysctl write.
+ *
+ *             User space may write new value at file position > 0. To override
+ *             the whole sysctl value file position should be set to zero.
+ *     Return
+ *             0 on success.
+ *
+ *             **-E2BIG** if the *buf_len* is too big.
+ *
+ *             **-EINVAL** if sysctl is being read.
  */
 #define __BPF_FUNC_MAPPER(FN)          \
        FN(unspec),                     \
@@ -2606,7 +2677,11 @@ union bpf_attr {
        FN(skb_ecn_set_ce),             \
        FN(get_listener_sock),          \
        FN(skc_lookup_tcp),             \
-       FN(tcp_check_syncookie),
+       FN(tcp_check_syncookie),        \
+       FN(sysctl_get_name),            \
+       FN(sysctl_get_current_value),   \
+       FN(sysctl_get_new_value),       \
+       FN(sysctl_set_new_value),
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper
  * function eBPF program intends to call
@@ -2679,6 +2754,9 @@ enum bpf_func_id {
                                          BPF_ADJ_ROOM_ENCAP_L2_MASK) \
                                         << BPF_ADJ_ROOM_ENCAP_L2_SHIFT)
 
+/* BPF_FUNC_sysctl_get_name flags. */
+#define BPF_F_SYSCTL_BASE_NAME         (1ULL << 0)
+
 /* Mode for BPF_FUNC_skb_adjust_room helper. */
 enum bpf_adj_room_mode {
        BPF_ADJ_ROOM_NET,
@@ -3308,4 +3386,14 @@ struct bpf_line_info {
 struct bpf_spin_lock {
        __u32   val;
 };
+
+struct bpf_sysctl {
+       __u32   write;          /* Sysctl is being read (= 0) or written (= 1).
+                                * Allows 1,2,4-byte read, but no write.
+                                */
+       __u32   file_pos;       /* Sysctl file position to read from, write to.
+                                * Allows 1,2,4-byte read an 4-byte write.
+                                */
+};
+
 #endif /* _UAPI__LINUX_BPF_H__ */