net/mlx5: Refactor accel IPSec code

The current code has one layer that executed FPGA commands and
the Ethernet part directly used this code. Since downstream patches
introduces support for IPSec in mlx5_ib, we need to provide some
abstractions. This patch refactors the accel code into one layer
that creates a software IPSec transformation and another one which
creates the actual hardware context.
The internal command implementation is now hidden in the FPGA
core layer. The code also adds the ability to share FPGA hardware
contexts. If two contexts are the same, only a reference count
is taken.

Signed-off-by: Aviad Yehezkel <aviadye@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

drivers/net/ethernet/mellanox/mlx5/core/accel/ipsec.c

@@ -37,27 +37,6 @@
 #include "mlx5_core.h"
 #include "fpga/ipsec.h"
 
-void *mlx5_accel_ipsec_sa_cmd_exec(struct mlx5_core_dev *mdev,
-				   struct mlx5_accel_ipsec_sa *cmd)
-{
-	int cmd_size;
-
-	if (!MLX5_IPSEC_DEV(mdev))
-		return ERR_PTR(-EOPNOTSUPP);
-
-	if (mlx5_accel_ipsec_device_caps(mdev) & MLX5_ACCEL_IPSEC_CAP_V2_CMD)
-		cmd_size = sizeof(*cmd);
-	else
-		cmd_size = sizeof(cmd->ipsec_sa_v1);
-
-	return mlx5_fpga_ipsec_sa_cmd_exec(mdev, cmd, cmd_size);
-}
-
-int mlx5_accel_ipsec_sa_cmd_wait(void *ctx)
-{
-	return mlx5_fpga_ipsec_sa_cmd_wait(ctx);
-}
-
 u32 mlx5_accel_ipsec_device_caps(struct mlx5_core_dev *mdev)
 {
 	return mlx5_fpga_ipsec_device_caps(mdev);
@@ -75,6 +54,21 @@ int mlx5_accel_ipsec_counters_read(struct mlx5_core_dev *mdev, u64 *counters,
 	return mlx5_fpga_ipsec_counters_read(mdev, counters, count);
 }
 
+void *mlx5_accel_esp_create_hw_context(struct mlx5_core_dev *mdev,
+				       struct mlx5_accel_esp_xfrm *xfrm,
+				       const __be32 saddr[4],
+				       const __be32 daddr[4],
+				       const __be32 spi, bool is_ipv6)
+{
+	return mlx5_fpga_ipsec_create_sa_ctx(mdev, xfrm, saddr, daddr,
+					     spi, is_ipv6);
+}
+
+void mlx5_accel_esp_free_hw_context(void *context)
+{
+	mlx5_fpga_ipsec_delete_sa_ctx(context);
+}
+
 int mlx5_accel_ipsec_init(struct mlx5_core_dev *mdev)
 {
 	return mlx5_fpga_ipsec_init(mdev);
@@ -84,3 +78,25 @@ void mlx5_accel_ipsec_cleanup(struct mlx5_core_dev *mdev)
 {
 	mlx5_fpga_ipsec_cleanup(mdev);
 }
+
+struct mlx5_accel_esp_xfrm *
+mlx5_accel_esp_create_xfrm(struct mlx5_core_dev *mdev,
+			   const struct mlx5_accel_esp_xfrm_attrs *attrs,
+			   u32 flags)
+{
+	struct mlx5_accel_esp_xfrm *xfrm;
+
+	xfrm = mlx5_fpga_esp_create_xfrm(mdev, attrs, flags);
+	if (IS_ERR(xfrm))
+		return xfrm;
+
+	xfrm->mdev = mdev;
+	return xfrm;
+}
+EXPORT_SYMBOL_GPL(mlx5_accel_esp_create_xfrm);
+
+void mlx5_accel_esp_destroy_xfrm(struct mlx5_accel_esp_xfrm *xfrm)
+{
+	mlx5_fpga_esp_destroy_xfrm(xfrm);
+}
+EXPORT_SYMBOL_GPL(mlx5_accel_esp_destroy_xfrm);

drivers/net/ethernet/mellanox/mlx5/core/accel/ipsec.h

@@ -39,96 +39,41 @@
 
 #ifdef CONFIG_MLX5_ACCEL
 
-#define MLX5_IPSEC_SADB_IP_AH       BIT(7)
-#define MLX5_IPSEC_SADB_IP_ESP      BIT(6)
-#define MLX5_IPSEC_SADB_SA_VALID    BIT(5)
-#define MLX5_IPSEC_SADB_SPI_EN      BIT(4)
-#define MLX5_IPSEC_SADB_DIR_SX      BIT(3)
-#define MLX5_IPSEC_SADB_IPV6        BIT(2)
-
-enum {
-	MLX5_IPSEC_CMD_ADD_SA = 0,
-	MLX5_IPSEC_CMD_DEL_SA = 1,
-	MLX5_IPSEC_CMD_ADD_SA_V2 = 2,
-	MLX5_IPSEC_CMD_DEL_SA_V2 = 3,
-	MLX5_IPSEC_CMD_MOD_SA_V2 = 4,
-	MLX5_IPSEC_CMD_SET_CAP = 5,
-};
-
-enum mlx5_accel_ipsec_enc_mode {
-	MLX5_IPSEC_SADB_MODE_NONE = 0,
-	MLX5_IPSEC_SADB_MODE_AES_GCM_128_AUTH_128 = 1,
-	MLX5_IPSEC_SADB_MODE_AES_GCM_256_AUTH_128 = 3,
-};
-
 #define MLX5_IPSEC_DEV(mdev) (mlx5_accel_ipsec_device_caps(mdev) & \
 			      MLX5_ACCEL_IPSEC_CAP_DEVICE)
 
-struct mlx5_accel_ipsec_sa_v1 {
-	__be32 cmd;
-	u8 key_enc[32];
-	u8 key_auth[32];
-	__be32 sip[4];
-	__be32 dip[4];
-	union {
-		struct {
-			__be32 reserved;
-			u8 salt_iv[8];
-			__be32 salt;
-		} __packed gcm;
-		struct {
-			u8 salt[16];
-		} __packed cbc;
-	};
-	__be32 spi;
-	__be32 sw_sa_handle;
-	__be16 tfclen;
-	u8 enc_mode;
-	u8 reserved1[2];
-	u8 flags;
-	u8 reserved2[2];
-};
-
-struct mlx5_accel_ipsec_sa {
-	struct mlx5_accel_ipsec_sa_v1 ipsec_sa_v1;
-	__be16 udp_sp;
-	__be16 udp_dp;
-	u8 reserved1[4];
-	__be32 esn;
-	__be16 vid;     /* only 12 bits, rest is reserved */
-	__be16 reserved2;
-} __packed;
-
-/**
- * mlx5_accel_ipsec_sa_cmd_exec - Execute an IPSec SADB command
- * @mdev: mlx5 device
- * @cmd: command to execute
- * May be called from atomic context. Returns context pointer, or error
- * Caller must eventually call mlx5_accel_ipsec_sa_cmd_wait from non-atomic
- * context, to cleanup the context pointer
- */
-void *mlx5_accel_ipsec_sa_cmd_exec(struct mlx5_core_dev *mdev,
-				   struct mlx5_accel_ipsec_sa *cmd);
-
-/**
- * mlx5_accel_ipsec_sa_cmd_wait - Wait for command execution completion
- * @context: Context pointer returned from call to mlx5_accel_ipsec_sa_cmd_exec
- * Sleeps (killable) until command execution is complete.
- * Returns the command result, or -EINTR if killed
- */
-int mlx5_accel_ipsec_sa_cmd_wait(void *context);
-
 unsigned int mlx5_accel_ipsec_counters_count(struct mlx5_core_dev *mdev);
 int mlx5_accel_ipsec_counters_read(struct mlx5_core_dev *mdev, u64 *counters,
 				   unsigned int count);
 
+void *mlx5_accel_esp_create_hw_context(struct mlx5_core_dev *mdev,
+				       struct mlx5_accel_esp_xfrm *xfrm,
+				       const __be32 saddr[4],
+				       const __be32 daddr[4],
+				       const __be32 spi, bool is_ipv6);
+void mlx5_accel_esp_free_hw_context(void *context);
+
 int mlx5_accel_ipsec_init(struct mlx5_core_dev *mdev);
 void mlx5_accel_ipsec_cleanup(struct mlx5_core_dev *mdev);
 
 #else
 
 #define MLX5_IPSEC_DEV(mdev) false
 
+static inline void *
+mlx5_accel_esp_create_hw_context(struct mlx5_core_dev *mdev,
+				 struct mlx5_accel_esp_xfrm *xfrm,
+				 const __be32 saddr[4],
+				 const __be32 daddr[4],
+				 const __be32 spi, bool is_ipv6)
+{
+	return NULL;
+}
+
+static inline void mlx5_accel_esp_free_hw_context(void *context)
+{
+}
+
 static inline int mlx5_accel_ipsec_init(struct mlx5_core_dev *mdev)
 {
 	return 0;