Re: [PATCH v3 11/19] net/mlx5e: Support PSP offload functionality

[Cosmin Ratiu <cratiu@nvidia.com>]

On Wed, 2025-07-02 at 10:13 -0700, Daniel Zahka wrote:
> From: Raed Salem <raeds@nvidia.com>
> 
> Add PSP offload related IFC structs, layouts, and enumerations.
> Implement
> .set_config and .rx_spi_alloc PSP device operations. Driver does not
> need
> to make use of the .set_config operation. Stub .assoc_add and
> .assoc_del
> PSP operations.
> 
> Introduce the MLX5_EN_PSP configuration option for enabling PSP
> offload
> support on mlx5 devices.
> 
> Signed-off-by: Raed Salem <raeds@nvidia.com>
> Signed-off-by: Rahul Rameshbabu <rrameshbabu@nvidia.com>
> Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
> ---
> 
> Notes:
>     v1:
>     -
> https://lore.kernel.org/netdev/20240510030435.120935-10-kuba@kernel.org/
> 
>  .../net/ethernet/mellanox/mlx5/core/Kconfig   |  11 ++
>  .../net/ethernet/mellanox/mlx5/core/Makefile  |   4 +-
>  drivers/net/ethernet/mellanox/mlx5/core/en.h  |   3 +
>  .../ethernet/mellanox/mlx5/core/en/params.c   |   4 +-
>  .../mellanox/mlx5/core/en_accel/psp.c         | 149
> ++++++++++++++++++
>  .../mellanox/mlx5/core/en_accel/psp.h         |  53 +++++++
>  .../mellanox/mlx5/core/en_accel/psp_offload.c |  52 ++++++
>  .../net/ethernet/mellanox/mlx5/core/en_main.c |   9 ++
>  drivers/net/ethernet/mellanox/mlx5/core/fw.c  |   6 +
>  .../net/ethernet/mellanox/mlx5/core/main.c    |   5 +
>  drivers/net/ethernet/mellanox/mlx5/core/psp.c |  24 +++
>  drivers/net/ethernet/mellanox/mlx5/core/psp.h |  15 ++
>  include/linux/mlx5/device.h                   |   4 +
>  include/linux/mlx5/driver.h                   |   2 +
>  include/linux/mlx5/mlx5_ifc.h                 |  94 ++++++++++-
>  15 files changed, 428 insertions(+), 7 deletions(-)
>  create mode 100644
> drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp.c
>  create mode 100644
> drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp.h
>  create mode 100644
> drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp_offload.c
>  create mode 100644 drivers/net/ethernet/mellanox/mlx5/core/psp.c
>  create mode 100644 drivers/net/ethernet/mellanox/mlx5/core/psp.h
> 
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/Kconfig
> b/drivers/net/ethernet/mellanox/mlx5/core/Kconfig
> index 6ec7d6e0181d..79a64489da89 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/Kconfig
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/Kconfig
> @@ -208,3 +208,14 @@ config MLX5_DPLL
>  	help
>  	  DPLL support in Mellanox Technologies ConnectX NICs.
>  
> +config MLX5_EN_PSP
> +	bool "Mellanox Technologies support for PSP cryptography-
> offload acceleration"
> +	depends on INET_PSP
> +	depends on MLX5_CORE_EN
> +	default y
> +	help
> +	  mlx5 device offload support for Google PSP Security
> Protocol offload.
> +	  Adds support for PSP encryption offload and for SPI and
> key generation
> +	  interfaces to PSP Stack which supports PSP crypto offload.
> +
> +	  If unsure, say Y.
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/Makefile
> b/drivers/net/ethernet/mellanox/mlx5/core/Makefile
> index d292e6a9e22c..e27de74ef028 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/Makefile
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/Makefile
> @@ -17,7 +17,7 @@ mlx5_core-y :=	main.o cmd.o debugfs.o fw.o
> eq.o uar.o pagealloc.o \
>  		fs_counters.o fs_ft_pool.o rl.o lag/debugfs.o
> lag/lag.o dev.o events.o wq.o lib/gid.o \
>  		lib/devcom.o lib/pci_vsc.o lib/dm.o lib/fs_ttc.o
> diag/fs_tracepoint.o \
>  		diag/fw_tracer.o diag/crdump.o devlink.o
> diag/rsc_dump.o diag/reporter_vnic.o \
> -		fw_reset.o qos.o lib/tout.o lib/aso.o wc.o fs_pool.o
> +		fw_reset.o qos.o lib/tout.o lib/aso.o wc.o fs_pool.o
> psp.o

Turns out, psp.c/psp.h and struct mlx5_psp aren't needed at all.
Please remove them, to avoid maintaining unnecessary boilerplate.
Here's a fixup patch which does this:

From ca3310c747dca55f7a139828e71457ac27b77889 Mon Sep 17 00:00:00 2001
From: Cosmin Ratiu <cratiu@nvidia.com>
Date: Fri, 11 Jul 2025 15:35:15 +0300
Subject: [PATCH 1/3] net/mlx5: fixup for unneded struct mlx5_psp

Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Change-Id: I8fcef314c53db25c0f3a73ff2daecf34d4d28fce
---
 .../net/ethernet/mellanox/mlx5/core/Makefile  |  2 +-
 .../net/ethernet/mellanox/mlx5/core/main.c    |  4 ----
 drivers/net/ethernet/mellanox/mlx5/core/psp.c | 24 -------------------
 drivers/net/ethernet/mellanox/mlx5/core/psp.h | 15 ------------
 include/linux/mlx5/driver.h                   |  2 --
 5 files changed, 1 insertion(+), 46 deletions(-)
 delete mode 100644 drivers/net/ethernet/mellanox/mlx5/core/psp.c
 delete mode 100644 drivers/net/ethernet/mellanox/mlx5/core/psp.h

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/Makefile
b/drivers/net/ethernet/mellanox/mlx5/core/Makefile
index 3761f5c104d3..ab35efdb7052 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/Makefile
+++ b/drivers/net/ethernet/mellanox/mlx5/core/Makefile
@@ -17,7 +17,7 @@ mlx5_core-y :=	main.o cmd.o debugfs.o fw.o
eq.o uar.o pagealloc.o \
 		fs_counters.o fs_ft_pool.o rl.o lag/debugfs.o
lag/lag.o dev.o events.o wq.o lib/gid.o \
 		lib/devcom.o lib/pci_vsc.o lib/dm.o lib/fs_ttc.o
diag/fs_tracepoint.o \
 		diag/fw_tracer.o diag/crdump.o devlink.o
diag/rsc_dump.o diag/reporter_vnic.o \
-		fw_reset.o qos.o lib/tout.o lib/aso.o wc.o fs_pool.o
psp.o
+		fw_reset.o qos.o lib/tout.o lib/aso.o wc.o fs_pool.o
 
 #
 # Netdev basic
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/main.c
b/drivers/net/ethernet/mellanox/mlx5/core/main.c
index 1890e4b09ffe..dc37b410799f 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/main.c
@@ -74,7 +74,6 @@
 #include "mlx5_irq.h"
 #include "hwmon.h"
 #include "lag/lag.h"
-#include "psp.h"
 
 MODULE_AUTHOR("Eli Cohen <eli@mellanox.com>");
 MODULE_DESCRIPTION("Mellanox 5th generation network adapters (ConnectX
series) core driver");
@@ -1047,7 +1046,6 @@ static int mlx5_init_once(struct mlx5_core_dev
*dev)
 
 	dev->vxlan = mlx5_vxlan_create(dev);
 	dev->geneve = mlx5_geneve_create(dev);
-	dev->psp = mlx5_psp_create(dev);
 
 	err = mlx5_init_rl_table(dev);
 	if (err) {
@@ -1130,7 +1128,6 @@ static int mlx5_init_once(struct mlx5_core_dev
*dev)
 err_rl_cleanup:
 	mlx5_cleanup_rl_table(dev);
 err_clock_cleanup:
-	mlx5_psp_destroy(dev->psp);
 	mlx5_geneve_destroy(dev->geneve);
 	mlx5_vxlan_destroy(dev->vxlan);
 	mlx5_cleanup_clock(dev);
@@ -1166,7 +1163,6 @@ static void mlx5_cleanup_once(struct
mlx5_core_dev *dev)
 	mlx5_sriov_cleanup(dev);
 	mlx5_mpfs_cleanup(dev);
 	mlx5_cleanup_rl_table(dev);
-	mlx5_psp_destroy(dev->psp);
 	mlx5_geneve_destroy(dev->geneve);
 	mlx5_vxlan_destroy(dev->vxlan);
 	mlx5_cleanup_clock(dev);
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/psp.c
b/drivers/net/ethernet/mellanox/mlx5/core/psp.c
deleted file mode 100644
index 15df8bde3632..000000000000
--- a/drivers/net/ethernet/mellanox/mlx5/core/psp.c
+++ /dev/null
@@ -1,24 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
-/* Copyright (c) 2023, NVIDIA CORPORATION & AFFILIATES. All rights
reserved. */
-
-#include "psp.h"
-
-struct mlx5_psp *mlx5_psp_create(struct mlx5_core_dev *mdev)
-{
-	struct mlx5_psp *psp = kzalloc(sizeof(*psp), GFP_KERNEL);
-
-	if (!psp)
-		return ERR_PTR(-ENOMEM);
-
-	psp->mdev = mdev;
-
-	return psp;
-}
-
-void mlx5_psp_destroy(struct mlx5_psp *psp)
-{
-	if (IS_ERR_OR_NULL(psp))
-		return;
-
-	kfree(psp);
-}
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/psp.h
b/drivers/net/ethernet/mellanox/mlx5/core/psp.h
deleted file mode 100644
index 1d7927c4ea72..000000000000
--- a/drivers/net/ethernet/mellanox/mlx5/core/psp.h
+++ /dev/null
@@ -1,15 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
-/* Copyright (c) 2023, NVIDIA CORPORATION & AFFILIATES. All rights
reserved. */
-
-#ifndef __MLX5_PSP_H__
-#define __MLX5_PSP_H__
-#include <linux/mlx5/driver.h>
-
-struct mlx5_psp {
-	struct mlx5_core_dev *mdev;
-};
-
-struct mlx5_psp *mlx5_psp_create(struct mlx5_core_dev *mdev);
-void mlx5_psp_destroy(struct mlx5_psp *psp);
-
-#endif /* __MLX5_PSP_H__ */
diff --git a/include/linux/mlx5/driver.h b/include/linux/mlx5/driver.h
index 671512699a92..e6ba8f4f4bd1 100644
--- a/include/linux/mlx5/driver.h
+++ b/include/linux/mlx5/driver.h
@@ -491,7 +491,6 @@ struct mlx5_sf_dev_table;
 struct mlx5_sf_hw_table;
 struct mlx5_sf_table;
 struct mlx5_crypto_dek_priv;
-struct mlx5_psp;
 
 struct mlx5_rate_limit {
 	u32			rate;
@@ -787,7 +786,6 @@ struct mlx5_core_dev {
 	enum mlx5_wc_state wc_state;
 	/* sync write combining state */
 	struct mutex wc_state_lock;
-	struct mlx5_psp         *psp;
 };
 
 struct mlx5_db {
-- 
2.45.0


> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp.h
> b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp.h
> new file mode 100644
> index 000000000000..9707f50029ed
> --- /dev/null
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp.h
> @@ -0,0 +1,53 @@
> +/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
> +/* Copyright (c) 2023, NVIDIA CORPORATION & AFFILIATES. All rights
> reserved. */
> +
> +#ifndef __MLX5E_ACCEL_PSP_H__
> +#define __MLX5E_ACCEL_PSP_H__
> +#if IS_ENABLED(CONFIG_MLX5_EN_PSP)
> +#include <net/psp/types.h>
> +#include "en.h"
> +
> +struct mlx5e_psp {
> +	struct psp_dev *psp;
> +	struct psp_dev_caps caps;
> +};
> +
> +struct psp_key_spi {
> +	u32 spi;
> +	__be32 key[PSP_MAX_KEY / sizeof(u32)];
> +	u16 keysz;
> +};

This intermediate structure doesn't help much, it's only used during
key generation and psp_key_parsed could be used directly. Here's a
fixup patch which simplifies things, and avoids boilerplate:

From 1ea9823416548f6ec673ed51ec05590fc4f910ab Mon Sep 17 00:00:00 2001
From: Cosmin Ratiu <cratiu@nvidia.com>
Date: Fri, 11 Jul 2025 15:37:00 +0300
Subject: [PATCH 2/2] net/mlx5e: fixup for mlx5e_psp_generate_key_spi

- use psp_key_parsed directly

Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Change-Id: Ie26552386fc415d23c0fbddb2408e8c7ecc05d8f
---
 .../mellanox/mlx5/core/en_accel/psp.c         | 12 ++------
 .../mellanox/mlx5/core/en_accel/psp.h         |  8 +----
 .../mellanox/mlx5/core/en_accel/psp_offload.c | 29 +++++++------------
 3 files changed, 13 insertions(+), 36 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp.c
b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp.c
index 288ed296b74c..cb429abc6b4b 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp.c
@@ -23,9 +23,7 @@ mlx5e_psp_rx_spi_alloc(struct psp_dev *psd, u32
version,
 {
 	struct mlx5e_priv *priv = netdev_priv(psd->main_netdev);
 	enum mlx5_psp_gen_spi_in_key_size keysz;
-	struct psp_key_spi key_spi = {};
 	u8 keysz_bytes;
-	int err;
 
 	switch (version) {
 	case PSP_VERSION_HDR0_AES_GCM_128:
@@ -40,14 +38,8 @@ mlx5e_psp_rx_spi_alloc(struct psp_dev *psd, u32
version,
 		return -EINVAL;
 	}
 
-	err = mlx5e_psp_generate_key_spi(priv->mdev, keysz,
keysz_bytes,
-					 &key_spi);
-	if (err)
-		return err;
-
-	assoc->spi = cpu_to_be32(key_spi.spi);
-	memcpy(assoc->key, key_spi.key, keysz_bytes);
-	return 0;
+	return mlx5e_psp_generate_key_spi(priv->mdev, keysz,
keysz_bytes,
+					  assoc);
 }
 
 struct psp_key {
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp.h
b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp.h
index 16e5ba591307..3f64a162f503 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp.h
@@ -14,12 +14,6 @@ struct mlx5e_psp {
 	atomic_t tx_key_cnt;
 };
 
-struct psp_key_spi {
-	u32 spi;
-	__be32 key[PSP_MAX_KEY / sizeof(u32)];
-	u16 keysz;
-};
-
 static inline bool mlx5_is_psp_device(struct mlx5_core_dev *mdev)
 {
 	if (!MLX5_CAP_GEN(mdev, psp))
@@ -40,7 +34,7 @@ int mlx5e_psp_rotate_key(struct mlx5_core_dev *mdev);
 int mlx5e_psp_generate_key_spi(struct mlx5_core_dev *mdev,
 			       enum mlx5_psp_gen_spi_in_key_size
keysz,
 			       unsigned int keysz_bytes,
-			       struct psp_key_spi *keys);
+			       struct psp_key_parsed *key);
 #else
 static inline bool mlx5_is_psp_device(struct mlx5_core_dev *mdev)
 {
diff --git
a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp_offload.c
b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp_offload.c
index c3c21a99a92b..a158ae407455 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp_offload.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp_offload.c
@@ -19,34 +19,25 @@ int mlx5e_psp_rotate_key(struct mlx5_core_dev
*mdev)
 int mlx5e_psp_generate_key_spi(struct mlx5_core_dev *mdev,
 			       enum mlx5_psp_gen_spi_in_key_size
keysz,
 			       unsigned int keysz_bytes,
-			       struct psp_key_spi *keys)
+			       struct psp_key_parsed *key)
 {
+	u32 out[MLX5_ST_SZ_DW(psp_gen_spi_out) +
MLX5_ST_SZ_DW(key_spi)] = {};
 	u32 in[MLX5_ST_SZ_DW(psp_gen_spi_in)] = {};
-	int err, outlen, i;
-	void *out, *outkey;
+	void *outkey;
+	int err;
 
 	WARN_ON_ONCE(keysz_bytes > PSP_MAX_KEY);
 
-	outlen = MLX5_ST_SZ_BYTES(psp_gen_spi_out) +
MLX5_ST_SZ_BYTES(key_spi);
-	out = kzalloc(outlen, GFP_KERNEL);
-	if (!out)
-		return -ENOMEM;
-
 	MLX5_SET(psp_gen_spi_in, in, opcode, MLX5_CMD_OP_PSP_GEN_SPI);
 	MLX5_SET(psp_gen_spi_in, in, key_size, keysz);
 	MLX5_SET(psp_gen_spi_in, in, num_of_spi, 1);
-	err = mlx5_cmd_exec(mdev, in, sizeof(in), out, outlen);
+	err = mlx5_cmd_exec(mdev, in, sizeof(in), out, sizeof(out));
 	if (err)
-		goto out;
+		return err;
 
 	outkey = MLX5_ADDR_OF(psp_gen_spi_out, out, key_spi);
-	keys->keysz = keysz_bytes * BITS_PER_BYTE;
-	keys->spi = MLX5_GET(key_spi, outkey, spi);
-	for (i = 0; i < keysz_bytes / sizeof(*keys->key); ++i)
-		keys->key[i] = cpu_to_be32(MLX5_GET(key_spi,
-						    outkey + (32 -
keysz_bytes), key[i]));
-
-out:
-	kfree(out);
-	return err;
+	key->spi = cpu_to_be32(MLX5_GET(key_spi, outkey, spi));
+	memcpy(key->key, MLX5_ADDR_OF(key_spi, outkey, key),
keysz_bytes);
+
+	return 0;
 }
-- 
2.45.0

Cosmin.