[PATCH v2 3/6] common/mlx5: add remote PD and CTX support

[Michael Baum <michaelba@nvidia.com>]

Add option to probe common device using import CTX/PD functions instead
of create functions.
This option requires accepting the context FD and the PD handle as
devargs.

This sharing can be useful for applications that use PMD for only some
operations. For example, an app that generates queues itself and uses
PMD just to configure flow rules.

Signed-off-by: Michael Baum <michaelba@nvidia.com>
---
 doc/guides/platform/mlx5.rst                 |  37 +++-
 drivers/common/mlx5/linux/mlx5_common_os.c   | 196 ++++++++++++++++---
 drivers/common/mlx5/linux/mlx5_common_os.h   |   6 -
 drivers/common/mlx5/mlx5_common.c            |  64 ++++--
 drivers/common/mlx5/mlx5_common.h            |  23 ++-
 drivers/common/mlx5/windows/mlx5_common_os.c |  37 +++-
 drivers/common/mlx5/windows/mlx5_common_os.h |   1 -
 7 files changed, 313 insertions(+), 51 deletions(-)

diff --git a/doc/guides/platform/mlx5.rst b/doc/guides/platform/mlx5.rst
index d073c213ca..d2ed094357 100644
--- a/doc/guides/platform/mlx5.rst
+++ b/doc/guides/platform/mlx5.rst
@@ -81,6 +81,12 @@ Limitations
 - On Windows, only ``eth`` and ``crypto`` are supported.
 
 
+Features
+--------
+
+- Remote PD and CTX - Linux only.
+
+
 .. _mlx5_common_compilation:
 
 Compilation Prerequisites
@@ -638,4 +644,33 @@ and below are the arguments supported by the common mlx5 layer.
 
   If ``sq_db_nc`` is omitted, the preset (if any) environment variable
   "MLX5_SHUT_UP_BF" value is used. If there is no "MLX5_SHUT_UP_BF", the
-  default ``sq_db_nc`` value is zero for ARM64 hosts and one for others.
\ No newline at end of file
+  default ``sq_db_nc`` value is zero for ARM64 hosts and one for others.
+
+- ``cmd_fd`` parameter [int]
+
+  File descriptor of ibv_context created outside the PMD.
+  PMD will use this FD to import remote CTX. The ``cmd_fd`` is obtained from
+  the ibv_context cmd_fd member, which must be dup'd before being passed.
+  This parameter is valid only if ``pd_handle`` parameter is specified.
+
+  By default, the PMD will ignore this parameter and create a new ibv_context.
+
+  .. note::
+
+     When FD comes from another process, it is on the user responsibility to
+     share the FD between the processes (e.g. by SCM_RIGHTS).
+
+- ``pd_handle`` parameter [int]
+
+  Protection domain handle of ibv_pd created outside the PMD.
+  PMD will use this handle to import remote PD. The ``pd_handle`` can be
+  achieved from the original PD by getting its ibv_pd->handle member value.
+  This parameter is valid only if ``cmd_fd`` parameter is specified, and its
+  value must be a valid kernel handle for a PD object in the context represented
+  by given ``cmd_fd``.
+
+  By default, the PMD will ignore this parameter and allocate a new PD.
+
+  .. note::
+
+     The ibv_pd->handle member is different then mlx5dv_pd->pdn member.
\ No newline at end of file
diff --git a/drivers/common/mlx5/linux/mlx5_common_os.c b/drivers/common/mlx5/linux/mlx5_common_os.c
index a752d79e8e..a3c25638da 100644
--- a/drivers/common/mlx5/linux/mlx5_common_os.c
+++ b/drivers/common/mlx5/linux/mlx5_common_os.c
@@ -408,27 +408,128 @@ mlx5_glue_constructor(void)
 }
 
 /**
- * Allocate Protection Domain object and extract its pdn using DV API.
+ * Validate user arguments for remote PD and CTX.
+ *
+ * @param config
+ *   Pointer to device configuration structure.
+ *
+ * @return
+ *   0 on success, a negative errno value otherwise and rte_errno is set.
+ */
+int
+mlx5_os_remote_pd_and_ctx_validate(struct mlx5_common_dev_config *config)
+{
+	int device_fd = config->device_fd;
+	int pd_handle = config->pd_handle;
+
+#ifdef HAVE_MLX5_IBV_IMPORT_CTX_PD_AND_MR
+	if (device_fd == MLX5_ARG_UNSET && pd_handle != MLX5_ARG_UNSET) {
+		DRV_LOG(ERR, "Remote PD without CTX is not supported.");
+		rte_errno = EINVAL;
+		return -rte_errno;
+	}
+	if (device_fd != MLX5_ARG_UNSET && pd_handle == MLX5_ARG_UNSET) {
+		DRV_LOG(ERR, "Remote CTX without PD is not supported.");
+		rte_errno = EINVAL;
+		return -rte_errno;
+	}
+	DRV_LOG(DEBUG, "Remote PD and CTX is supported: (cmd_fd=%d, "
+		"pd_handle=%d).", device_fd, pd_handle);
+#else
+	if (pd_handle != MLX5_ARG_UNSET || device_fd != MLX5_ARG_UNSET) {
+		DRV_LOG(ERR,
+			"Remote PD and CTX is not supported - maybe old rdma-core version?");
+		rte_errno = ENOTSUP;
+		return -rte_errno;
+	}
+#endif
+	return 0;
+}
+
+/**
+ * Release Protection Domain object.
  *
  * @param[out] cdev
  *   Pointer to the mlx5 device.
  *
  * @return
- *   0 on success, a negative errno value otherwise and rte_errno is set.
+ *   0 on success, a negative errno value otherwise.
  */
 int
+mlx5_os_pd_release(struct mlx5_common_device *cdev)
+{
+	if (cdev->config.pd_handle == MLX5_ARG_UNSET)
+		return mlx5_glue->dealloc_pd(cdev->pd);
+	else
+		return mlx5_glue->unimport_pd(cdev->pd);
+}
+
+/**
+ * Allocate Protection Domain object.
+ *
+ * @param[out] cdev
+ *   Pointer to the mlx5 device.
+ *
+ * @return
+ *   0 on success, a negative errno value otherwise.
+ */
+static int
 mlx5_os_pd_create(struct mlx5_common_device *cdev)
+{
+	cdev->pd = mlx5_glue->alloc_pd(cdev->ctx);
+	if (cdev->pd == NULL) {
+		DRV_LOG(ERR, "Failed to allocate PD: %s", rte_strerror(errno));
+		return errno ? -errno : -ENOMEM;
+	}
+	return 0;
+}
+
+/**
+ * Import Protection Domain object according to given PD handle.
+ *
+ * @param[out] cdev
+ *   Pointer to the mlx5 device.
+ *
+ * @return
+ *   0 on success, a negative errno value otherwise.
+ */
+static int
+mlx5_os_pd_import(struct mlx5_common_device *cdev)
+{
+	cdev->pd = mlx5_glue->import_pd(cdev->ctx, cdev->config.pd_handle);
+	if (cdev->pd == NULL) {
+		DRV_LOG(ERR, "Failed to import PD using handle=%d: %s",
+			cdev->config.pd_handle, rte_strerror(errno));
+		return errno ? -errno : -ENOMEM;
+	}
+	return 0;
+}
+
+/**
+ * Prepare Protection Domain object and extract its pdn using DV API.
+ *
+ * @param[out] cdev
+ *   Pointer to the mlx5 device.
+ *
+ * @return
+ *   0 on success, a negative errno value otherwise and rte_errno is set.
+ */
+int
+mlx5_os_pd_prepare(struct mlx5_common_device *cdev)
 {
 #ifdef HAVE_IBV_FLOW_DV_SUPPORT
 	struct mlx5dv_obj obj;
 	struct mlx5dv_pd pd_info;
-	int ret;
 #endif
+	int ret;
 
-	cdev->pd = mlx5_glue->alloc_pd(cdev->ctx);
-	if (cdev->pd == NULL) {
-		DRV_LOG(ERR, "Failed to allocate PD.");
-		return errno ? -errno : -ENOMEM;
+	if (cdev->config.pd_handle == MLX5_ARG_UNSET)
+		ret = mlx5_os_pd_create(cdev);
+	else
+		ret = mlx5_os_pd_import(cdev);
+	if (ret) {
+		rte_errno = -ret;
+		return ret;
 	}
 	if (cdev->config.devx == 0)
 		return 0;
@@ -438,15 +539,17 @@ mlx5_os_pd_create(struct mlx5_common_device *cdev)
 	ret = mlx5_glue->dv_init_obj(&obj, MLX5DV_OBJ_PD);
 	if (ret != 0) {
 		DRV_LOG(ERR, "Fail to get PD object info.");
-		mlx5_glue->dealloc_pd(cdev->pd);
+		rte_errno = errno;
+		claim_zero(mlx5_os_pd_release(cdev));
 		cdev->pd = NULL;
-		return -errno;
+		return -rte_errno;
 	}
 	cdev->pdn = pd_info.pdn;
 	return 0;
 #else
 	DRV_LOG(ERR, "Cannot get pdn - no DV support.");
-	return -ENOTSUP;
+	rte_errno = ENOTSUP;
+	return -rte_errno;
 #endif /* HAVE_IBV_FLOW_DV_SUPPORT */
 }
 
@@ -648,28 +751,28 @@ mlx5_restore_doorbell_mapping_env(int value)
 /**
  * Function API to open IB device.
  *
- *
  * @param cdev
  *   Pointer to the mlx5 device.
  * @param classes
  *   Chosen classes come from device arguments.
  *
  * @return
- *   0 on success, a negative errno value otherwise and rte_errno is set.
+ *   Pointer to ibv_context on success, NULL otherwise and rte_errno is set.
  */
-int
-mlx5_os_open_device(struct mlx5_common_device *cdev, uint32_t classes)
+static struct ibv_context *
+mlx5_open_device(struct mlx5_common_device *cdev, uint32_t classes)
 {
 	struct ibv_device *ibv;
 	struct ibv_context *ctx = NULL;
 	int dbmap_env;
 
+	MLX5_ASSERT(cdev->config.device_fd == MLX5_ARG_UNSET);
 	if (classes & MLX5_CLASS_VDPA)
 		ibv = mlx5_vdpa_get_ibv_dev(cdev->dev);
 	else
 		ibv = mlx5_os_get_ibv_dev(cdev->dev);
 	if (!ibv)
-		return -rte_errno;
+		return NULL;
 	DRV_LOG(INFO, "Dev information matches for device \"%s\".", ibv->name);
 	/*
 	 * Configure environment variable "MLX5_BF_SHUT_UP" before the device
@@ -682,29 +785,78 @@ mlx5_os_open_device(struct mlx5_common_device *cdev, uint32_t classes)
 	ctx = mlx5_glue->dv_open_device(ibv);
 	if (ctx) {
 		cdev->config.devx = 1;
-		DRV_LOG(DEBUG, "DevX is supported.");
 	} else if (classes == MLX5_CLASS_ETH) {
 		/* The environment variable is still configured. */
 		ctx = mlx5_glue->open_device(ibv);
 		if (ctx == NULL)
 			goto error;
-		DRV_LOG(DEBUG, "DevX is NOT supported.");
 	} else {
 		goto error;
 	}
 	/* The device is created, no need for environment. */
 	mlx5_restore_doorbell_mapping_env(dbmap_env);
-	/* Hint libmlx5 to use PMD allocator for data plane resources */
-	mlx5_set_context_attr(cdev->dev, ctx);
-	cdev->ctx = ctx;
-	return 0;
+	return ctx;
 error:
 	rte_errno = errno ? errno : ENODEV;
 	/* The device creation is failed, no need for environment. */
 	mlx5_restore_doorbell_mapping_env(dbmap_env);
 	DRV_LOG(ERR, "Failed to open IB device \"%s\".", ibv->name);
-	return -rte_errno;
+	return NULL;
+}
+
+/**
+ * Function API to import IB device.
+ *
+ * @param cdev
+ *   Pointer to the mlx5 device.
+ *
+ * @return
+ *   Pointer to ibv_context on success, NULL otherwise and rte_errno is set.
+ */
+static struct ibv_context *
+mlx5_import_device(struct mlx5_common_device *cdev)
+{
+	struct ibv_context *ctx = NULL;
+
+	MLX5_ASSERT(cdev->config.device_fd != MLX5_ARG_UNSET);
+	ctx = mlx5_glue->import_device(cdev->config.device_fd);
+	if (!ctx) {
+		DRV_LOG(ERR, "Failed to import device for fd=%d: %s",
+			cdev->config.device_fd, rte_strerror(errno));
+		rte_errno = errno;
+	}
+	return ctx;
+}
+
+/**
+ * Function API to prepare IB device.
+ *
+ * @param cdev
+ *   Pointer to the mlx5 device.
+ * @param classes
+ *   Chosen classes come from device arguments.
+ *
+ * @return
+ *   0 on success, a negative errno value otherwise and rte_errno is set.
+ */
+int
+mlx5_os_open_device(struct mlx5_common_device *cdev, uint32_t classes)
+{
+
+	struct ibv_context *ctx = NULL;
+
+	if (cdev->config.device_fd == MLX5_ARG_UNSET)
+		ctx = mlx5_open_device(cdev, classes);
+	else
+		ctx = mlx5_import_device(cdev);
+	if (ctx == NULL)
+		return -rte_errno;
+	/* Hint libmlx5 to use PMD allocator for data plane resources */
+	mlx5_set_context_attr(cdev->dev, ctx);
+	cdev->ctx = ctx;
+	return 0;
 }
+
 int
 mlx5_get_device_guid(const struct rte_pci_addr *dev, uint8_t *guid, size_t len)
 {
diff --git a/drivers/common/mlx5/linux/mlx5_common_os.h b/drivers/common/mlx5/linux/mlx5_common_os.h
index edf356a30a..a85f3b5f3c 100644
--- a/drivers/common/mlx5/linux/mlx5_common_os.h
+++ b/drivers/common/mlx5/linux/mlx5_common_os.h
@@ -203,12 +203,6 @@ mlx5_os_get_devx_uar_page_id(void *uar)
 #endif
 }
 
-static inline int
-mlx5_os_dealloc_pd(void *pd)
-{
-	return mlx5_glue->dealloc_pd(pd);
-}
-
 __rte_internal
 static inline void *
 mlx5_os_umem_reg(void *ctx, void *addr, size_t size, uint32_t access)
diff --git a/drivers/common/mlx5/mlx5_common.c b/drivers/common/mlx5/mlx5_common.c
index 8cf391df13..2175cea25d 100644
--- a/drivers/common/mlx5/mlx5_common.c
+++ b/drivers/common/mlx5/mlx5_common.c
@@ -24,6 +24,12 @@ uint8_t haswell_broadwell_cpu;
 /* Driver type key for new device global syntax. */
 #define MLX5_DRIVER_KEY "driver"
 
+/* Device parameter to get file descriptor for import device. */
+#define MLX5_DEVICE_FD "cmd_fd"
+
+/* Device parameter to get PD number for import Protection Domain. */
+#define MLX5_PD_HANDLE "pd_handle"
+
 /* Enable extending memsegs when creating a MR. */
 #define MLX5_MR_EXT_MEMSEG_EN "mr_ext_memseg_en"
 
@@ -283,6 +289,10 @@ mlx5_common_args_check_handler(const char *key, const char *val, void *opaque)
 		config->mr_mempool_reg_en = !!tmp;
 	} else if (strcmp(key, MLX5_SYS_MEM_EN) == 0) {
 		config->sys_mem_en = !!tmp;
+	} else if (strcmp(key, MLX5_DEVICE_FD) == 0) {
+		config->device_fd = tmp;
+	} else if (strcmp(key, MLX5_PD_HANDLE) == 0) {
+		config->pd_handle = tmp;
 	}
 	return 0;
 }
@@ -310,6 +320,8 @@ mlx5_common_config_get(struct mlx5_kvargs_ctrl *mkvlist,
 		MLX5_MR_EXT_MEMSEG_EN,
 		MLX5_SYS_MEM_EN,
 		MLX5_MR_MEMPOOL_REG_EN,
+		MLX5_DEVICE_FD,
+		MLX5_PD_HANDLE,
 		NULL,
 	};
 	int ret = 0;
@@ -321,13 +333,19 @@ mlx5_common_config_get(struct mlx5_kvargs_ctrl *mkvlist,
 	config->mr_mempool_reg_en = 1;
 	config->sys_mem_en = 0;
 	config->dbnc = MLX5_ARG_UNSET;
+	config->device_fd = MLX5_ARG_UNSET;
+	config->pd_handle = MLX5_ARG_UNSET;
 	/* Process common parameters. */
 	ret = mlx5_kvargs_process(mkvlist, params,
 				  mlx5_common_args_check_handler, config);
 	if (ret) {
 		rte_errno = EINVAL;
-		ret = -rte_errno;
+		return -rte_errno;
 	}
+	/* Validate user arguments for remote PD and CTX if it is given. */
+	ret = mlx5_os_remote_pd_and_ctx_validate(config);
+	if (ret)
+		return ret;
 	DRV_LOG(DEBUG, "mr_ext_memseg_en is %u.", config->mr_ext_memseg_en);
 	DRV_LOG(DEBUG, "mr_mempool_reg_en is %u.", config->mr_mempool_reg_en);
 	DRV_LOG(DEBUG, "sys_mem_en is %u.", config->sys_mem_en);
@@ -645,7 +663,7 @@ static void
 mlx5_dev_hw_global_release(struct mlx5_common_device *cdev)
 {
 	if (cdev->pd != NULL) {
-		claim_zero(mlx5_os_dealloc_pd(cdev->pd));
+		claim_zero(mlx5_os_pd_release(cdev));
 		cdev->pd = NULL;
 	}
 	if (cdev->ctx != NULL) {
@@ -674,20 +692,27 @@ mlx5_dev_hw_global_prepare(struct mlx5_common_device *cdev, uint32_t classes)
 	ret = mlx5_os_open_device(cdev, classes);
 	if (ret < 0)
 		return ret;
-	/* Allocate Protection Domain object and extract its pdn. */
-	ret = mlx5_os_pd_create(cdev);
+	/*
+	 * When CTX is created by Verbs, query HCA attribute is unsupported.
+	 * When CTX is imported, we cannot know if it is created by DevX or
+	 * Verbs. So, we use query HCA attribute function to check it.
+	 */
+	if (cdev->config.devx || cdev->config.device_fd != MLX5_ARG_UNSET) {
+		/* Query HCA attributes. */
+		ret = mlx5_devx_cmd_query_hca_attr(cdev->ctx,
+						   &cdev->config.hca_attr);
+		if (ret) {
+			DRV_LOG(ERR, "Unable to read HCA caps in DevX mode.");
+			rte_errno = ENOTSUP;
+			goto error;
+		}
+		cdev->config.devx = 1;
+	}
+	DRV_LOG(DEBUG, "DevX is %ssupported.", cdev->config.devx ? "" : "NOT ");
+	/* Prepare Protection Domain object and extract its pdn. */
+	ret = mlx5_os_pd_prepare(cdev);
 	if (ret)
 		goto error;
-	/* All actions taken below are relevant only when DevX is supported */
-	if (cdev->config.devx == 0)
-		return 0;
-	/* Query HCA attributes. */
-	ret = mlx5_devx_cmd_query_hca_attr(cdev->ctx, &cdev->config.hca_attr);
-	if (ret) {
-		DRV_LOG(ERR, "Unable to read HCA capabilities.");
-		rte_errno = ENOTSUP;
-		goto error;
-	}
 	return 0;
 error:
 	mlx5_dev_hw_global_release(cdev);
@@ -826,6 +851,17 @@ mlx5_common_probe_again_args_validate(struct mlx5_common_device *cdev,
 			cdev->dev->name);
 		goto error;
 	}
+	if (cdev->config.device_fd ^ config->device_fd) {
+		DRV_LOG(ERR, "\"cmd_fd\" configuration mismatch for device %s.",
+			cdev->dev->name);
+		goto error;
+	}
+	if (cdev->config.pd_handle ^ config->pd_handle) {
+		DRV_LOG(ERR,
+			"\"pd_handle\" configuration mismatch for device %s.",
+			cdev->dev->name);
+		goto error;
+	}
 	if (cdev->config.sys_mem_en ^ config->sys_mem_en) {
 		DRV_LOG(ERR,
 			"\"sys_mem_en\" configuration mismatch for device %s.",
diff --git a/drivers/common/mlx5/mlx5_common.h b/drivers/common/mlx5/mlx5_common.h
index 49bcea1d91..451cdb4fad 100644
--- a/drivers/common/mlx5/mlx5_common.h
+++ b/drivers/common/mlx5/mlx5_common.h
@@ -446,6 +446,8 @@ void mlx5_common_init(void);
 struct mlx5_common_dev_config {
 	struct mlx5_hca_attr hca_attr; /* HCA attributes. */
 	int dbnc; /* Skip doorbell register write barrier. */
+	int device_fd; /* Device file descriptor for importation. */
+	int pd_handle; /* Protection Domain handle for importation.  */
 	unsigned int devx:1; /* Whether devx interface is available or not. */
 	unsigned int sys_mem_en:1; /* The default memory allocator. */
 	unsigned int mr_mempool_reg_en:1;
@@ -465,6 +467,23 @@ struct mlx5_common_device {
 	struct mlx5_common_dev_config config; /* Device configuration. */
 };
 
+/**
+ * Indicates whether PD and CTX are imported from another process,
+ * or created by this process.
+ *
+ * @param cdev
+ *   Pointer to common device.
+ *
+ * @return
+ *   True if PD and CTX are imported from another process, False otherwise.
+ */
+static inline bool
+mlx5_imported_pd_and_ctx(struct mlx5_common_device *cdev)
+{
+	return (cdev->config.device_fd != MLX5_ARG_UNSET &&
+		cdev->config.pd_handle != MLX5_ARG_UNSET);
+}
+
 /**
  * Initialization function for the driver called during device probing.
  */
@@ -554,7 +573,9 @@ mlx5_devx_uar_release(struct mlx5_uar *uar);
 /* mlx5_common_os.c */
 
 int mlx5_os_open_device(struct mlx5_common_device *cdev, uint32_t classes);
-int mlx5_os_pd_create(struct mlx5_common_device *cdev);
+int mlx5_os_pd_prepare(struct mlx5_common_device *cdev);
+int mlx5_os_pd_release(struct mlx5_common_device *cdev);
+int mlx5_os_remote_pd_and_ctx_validate(struct mlx5_common_dev_config *config);
 
 /* mlx5 PMD wrapped MR struct. */
 struct mlx5_pmd_wrapped_mr {
diff --git a/drivers/common/mlx5/windows/mlx5_common_os.c b/drivers/common/mlx5/windows/mlx5_common_os.c
index c3cfc315f2..f2fc7cd494 100644
--- a/drivers/common/mlx5/windows/mlx5_common_os.c
+++ b/drivers/common/mlx5/windows/mlx5_common_os.c
@@ -25,21 +25,46 @@ mlx5_glue_constructor(void)
 {
 }
 
+/**
+ * Validate user arguments for remote PD and CTX.
+ *
+ * @param config
+ *   Pointer to device configuration structure.
+ *
+ * @return
+ *   0 on success, a negative errno value otherwise and rte_errno is set.
+ */
+int
+mlx5_os_remote_pd_and_ctx_validate(struct mlx5_common_dev_config *config)
+{
+	int device_fd = config->device_fd;
+	int pd_handle = config->pd_handle;
+
+	if (pd_handle != MLX5_ARG_UNSET || device_fd != MLX5_ARG_UNSET) {
+		DRV_LOG(ERR, "Remote PD and CTX is not supported on Windows.");
+		rte_errno = ENOTSUP;
+		return -rte_errno;
+	}
+	return 0;
+}
+
 /**
  * Release PD. Releases a given mlx5_pd object
  *
- * @param[in] pd
- *   Pointer to mlx5_pd.
+ * @param[in] cdev
+ *   Pointer to the mlx5 device.
  *
  * @return
  *   Zero if pd is released successfully, negative number otherwise.
  */
 int
-mlx5_os_dealloc_pd(void *pd)
+mlx5_os_pd_release(struct mlx5_common_device *cdev)
 {
+	struct mlx5_pd *pd = cdev->pd;
+
 	if (!pd)
 		return -EINVAL;
-	mlx5_devx_cmd_destroy(((struct mlx5_pd *)pd)->obj);
+	mlx5_devx_cmd_destroy(pd->obj);
 	mlx5_free(pd);
 	return 0;
 }
@@ -47,14 +72,14 @@ mlx5_os_dealloc_pd(void *pd)
 /**
  * Allocate Protection Domain object and extract its pdn using DV API.
  *
- * @param[out] dev
+ * @param[out] cdev
  *   Pointer to the mlx5 device.
  *
  * @return
  *   0 on success, a negative value otherwise.
  */
 int
-mlx5_os_pd_create(struct mlx5_common_device *cdev)
+mlx5_os_pd_prepare(struct mlx5_common_device *cdev)
 {
 	struct mlx5_pd *pd;
 
diff --git a/drivers/common/mlx5/windows/mlx5_common_os.h b/drivers/common/mlx5/windows/mlx5_common_os.h
index 61fc8dd761..ee7973f1ec 100644
--- a/drivers/common/mlx5/windows/mlx5_common_os.h
+++ b/drivers/common/mlx5/windows/mlx5_common_os.h
@@ -248,7 +248,6 @@ mlx5_os_devx_subscribe_devx_event(void *eventc,
 	return -ENOTSUP;
 }
 
-int mlx5_os_dealloc_pd(void *pd);
 __rte_internal
 void *mlx5_os_umem_reg(void *ctx, void *addr, size_t size, uint32_t access);
 __rte_internal
-- 
2.25.1