IB/uverbs: Add flow_action create and destroy verbs

A verbs application may receive and transmits packets using a data
path pipeline. Sometimes, the first stage in the receive pipeline or
the last stage in the transmit pipeline involves transforming a
packet, either in order to make it easier for later stages to process
it or to prepare it for transmission over the wire. Such transformation
could be stripping/encapsulating the packet (i.e. vxlan),
decrypting/encrypting it (i.e. ipsec), altering headers, doing some
complex FPGA changes, etc.

Some hardware could do such transformations without software data path
intervention at all. The flow steering API supports steering a
packet (either to a QP or dropping it) and some simple packet
immutable actions (i.e. tagging a packet). Complex actions, that may
change the packet, could bloat the flow steering API extensively.
Sometimes the same action should be applied to several flows.
In this case, it's easier to bind several flows to the same action and
modify it than change all matching flows.

Introducing a new flow_action object that abstracts any packet
transformation (out of a standard and well defined set of actions).
This flow_action object could be tied to a flow steering rule via a
new specification.

Currently, we support esp flow_action, which encrypts or decrypts a
packet according to the given parameters. However, we present a
flexible schema that could be used to other transformation actions tied
to flow rules.

Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

1 files changed, 65 insertions, 0 deletions

diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index 1e3059ce73b6..49da92143341 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -65,6 +65,7 @@
 #include <uapi/rdma/ib_user_verbs.h>
 #include <rdma/restrack.h>
 #include <uapi/rdma/rdma_user_ioctl.h>
+#include <uapi/rdma/ib_user_ioctl_verbs.h>
 
 #define IB_FW_VERSION_NAME_MAX	ETHTOOL_FWVERS_LEN
 
@@ -2001,6 +2002,63 @@ struct ib_flow {
 	struct ib_uobject	*uobject;
 };
 
+enum ib_flow_action_type {
+	IB_FLOW_ACTION_UNSPECIFIED,
+	IB_FLOW_ACTION_ESP = 1,
+};
+
+struct ib_flow_action_attrs_esp_keymats {
+	enum ib_uverbs_flow_action_esp_keymat			protocol;
+	union {
+		struct ib_uverbs_flow_action_esp_keymat_aes_gcm aes_gcm;
+	} keymat;
+};
+
+struct ib_flow_action_attrs_esp_replays {
+	enum ib_uverbs_flow_action_esp_replay			protocol;
+	union {
+		struct ib_uverbs_flow_action_esp_replay_bmp	bmp;
+	} replay;
+};
+
+enum ib_flow_action_attrs_esp_flags {
+	/* All user-space flags at the top: Use enum ib_uverbs_flow_action_esp_flags
+	 * This is done in order to share the same flags between user-space and
+	 * kernel and spare an unnecessary translation.
+	 */
+
+	/* Kernel flags */
+	IB_FLOW_ACTION_ESP_FLAGS_ESN_TRIGGERED	= 1ULL << 32,
+};
+
+struct ib_flow_spec_list {
+	struct ib_flow_spec_list	*next;
+	union ib_flow_spec		spec;
+};
+
+struct ib_flow_action_attrs_esp {
+	struct ib_flow_action_attrs_esp_keymats		*keymat;
+	struct ib_flow_action_attrs_esp_replays		*replay;
+	struct ib_flow_spec_list			*encap;
+	/* Used only if IB_FLOW_ACTION_ESP_FLAGS_ESN_TRIGGERED is enabled.
+	 * Value of 0 is a valid value.
+	 */
+	u32						esn;
+	u32						spi;
+	u32						seq;
+	u32						tfc_pad;
+	/* Use enum ib_flow_action_attrs_esp_flags */
+	u64						flags;
+	u64						hard_limit_pkts;
+};
+
+struct ib_flow_action {
+	struct ib_device		*device;
+	struct ib_uobject		*uobject;
+	enum ib_flow_action_type	type;
+	atomic_t			usecnt;
+};
+
 struct ib_mad_hdr;
 struct ib_grh;
 
@@ -2077,6 +2135,8 @@ struct ib_port_pkey_list {
 	struct list_head              pkey_list;
 };
 
+struct uverbs_attr_bundle;
+
 struct ib_device {
 	/* Do not access @dma_device directly from ULP nor from HW drivers. */
 	struct device                *dma_device;
@@ -2331,6 +2391,11 @@ struct ib_device {
 							   struct ib_rwq_ind_table_init_attr *init_attr,
 							   struct ib_udata *udata);
 	int                        (*destroy_rwq_ind_table)(struct ib_rwq_ind_table *wq_ind_table);
+	struct ib_flow_action *	   (*create_flow_action_esp)(struct ib_device *device,
+							     const struct ib_flow_action_attrs_esp *attr,
+							     struct uverbs_attr_bundle *attrs);
+	int			   (*destroy_flow_action)(struct ib_flow_action *action);
+
 	/**
 	 * rdma netdev operation
 	 *