path: root/meta-v1000/recipes-kernel/linux/linux-yocto-4.14.71/1132-drm-amdkfd-Automatically-detect-and-enable-PeerDirec.patch

From 35ed769b72218c7f3bcc4d36de2ca3ee68be1eb7 Mon Sep 17 00:00:00 2001
From: Serguei Sagalovitch <Serguei.Sagalovitch@amd.com>
Date: Tue, 26 Apr 2016 15:23:28 -0400
Subject: [PATCH 1132/4131] drm/amdkfd: Automatically detect and enable
 PeerDirect support v3

Normally PeerDirect is delivered  as part of OFED package. Accordingly
we are not able to rely on the fact that PeerDirect is present
in the system. To improve user experience and to be "PeerDirect"
-ready the logic implemented to detect PeerDirect interface presence
and creating  PeerDirect "bridge".

v2: Switch to use "symbol_request"/"symbol_put" instead of relying on
kallsyms support. Use PAGE_SIZE macro instead of hardcoded value.
Fix grammar errors. Update comments.
v3: Fixed errors in kfd_close_peer_direct() function

Change-Id: I49ea6b0a1d80d7189eef4a16e15e4b7237b00168
Signed-off-by: Serguei Sagalovitch <Serguei.Sagalovitch@amd.com>
---
 drivers/gpu/drm/amd/amdkfd/Makefile         |   3 +-
 drivers/gpu/drm/amd/amdkfd/kfd_module.c     |   4 +
 drivers/gpu/drm/amd/amdkfd/kfd_peerdirect.c | 488 ++++++++++++++++++++++++++++
 drivers/gpu/drm/amd/amdkfd/kfd_priv.h       |   5 +
 4 files changed, 499 insertions(+), 1 deletion(-)
 create mode 100644 drivers/gpu/drm/amd/amdkfd/kfd_peerdirect.c

diff --git a/drivers/gpu/drm/amd/amdkfd/Makefile b/drivers/gpu/drm/amd/amdkfd/Makefile
index b5d3db9..59d284e 100644
--- a/drivers/gpu/drm/amd/amdkfd/Makefile
+++ b/drivers/gpu/drm/amd/amdkfd/Makefile
@@ -15,6 +15,7 @@ amdkfd-y	:= kfd_module.o kfd_device.o kfd_chardev.o kfd_topology.o \
 		kfd_process_queue_manager.o kfd_device_queue_manager.o \
 		kfd_device_queue_manager_cik.o kfd_device_queue_manager_vi.o \
 		kfd_interrupt.o kfd_events.o cik_event_interrupt.o \
-		kfd_dbgdev.o kfd_dbgmgr.o kfd_flat_memory.o kfd_crat.o kfd_rdma.o
+		kfd_dbgdev.o kfd_dbgmgr.o kfd_flat_memory.o kfd_crat.o kfd_rdma.o \
+		kfd_peerdirect.o
 
 obj-$(CONFIG_HSA_AMD)	+= amdkfd.o
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_module.c b/drivers/gpu/drm/amd/amdkfd/kfd_module.c
index bb0b00d..3109273 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_module.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_module.c
@@ -137,6 +137,9 @@ static int __init kfd_module_init(void)
 
 	amdkfd_init_completed = 1;
 
+	if (!kfd_init_peer_direct())
+		pr_info("PeerDirect support was enabled\n");
+
 	dev_info(kfd_device, "Initialized module\n");
 
 	return 0;
@@ -153,6 +156,7 @@ static void __exit kfd_module_exit(void)
 {
 	amdkfd_init_completed = 0;
 
+	kfd_close_peer_direct();
 	kfd_process_destroy_wq();
 	kfd_topology_shutdown();
 	kfd_chardev_exit();
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_peerdirect.c b/drivers/gpu/drm/amd/amdkfd/kfd_peerdirect.c
new file mode 100644
index 0000000..ffbccb3
--- /dev/null
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_peerdirect.c
@@ -0,0 +1,488 @@
+/*
+ * Copyright 2016 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+
+/* NOTE:
+ *
+ * This file contains logic to dynamically detect and enable PeerDirect
+ * suppor. PeerDirect support is delivered e.g. as part of OFED
+ * from Mellanox. Because we are not able to rely on the fact that the
+ * corresponding OFED will be installed we should:
+ *  - copy PeerDirect definitions locally to avoid dependency on
+ *    corresponding header file
+ *  - try dynamically detect address of PeerDirect function
+ *    pointers.
+ *
+ * If dynamic detection failed then PeerDirect support should be
+ * enabled using the standard PeerDirect bridge driver from:
+ * https://github.com/RadeonOpenCompute/ROCnRDMA
+ *
+ *
+ * Logic to support PeerDirect relies only on official public API to be
+ * non-intrusive as much as possible.
+ *
+ **/
+
+#include <linux/device.h>
+#include <linux/export.h>
+#include <linux/pid.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/scatterlist.h>
+#include <linux/module.h>
+#include "amd_rdma.h"
+
+
+
+/* ----------------------- PeerDirect interface ------------------------------*/
+
+/*
+ * Copyright (c) 2013,  Mellanox Technologies. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer in the documentation and/or other materials
+ *        provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+#define IB_PEER_MEMORY_NAME_MAX 64
+#define IB_PEER_MEMORY_VER_MAX 16
+
+struct peer_memory_client {
+	char	name[IB_PEER_MEMORY_NAME_MAX];
+	char	version[IB_PEER_MEMORY_VER_MAX];
+	/* acquire return code: 1-mine, 0-not mine */
+	int (*acquire)(unsigned long addr, size_t size,
+			void *peer_mem_private_data,
+					char *peer_mem_name,
+					void **client_context);
+	int (*get_pages)(unsigned long addr,
+			  size_t size, int write, int force,
+			  struct sg_table *sg_head,
+			  void *client_context, void *core_context);
+	int (*dma_map)(struct sg_table *sg_head, void *client_context,
+			struct device *dma_device, int dmasync, int *nmap);
+	int (*dma_unmap)(struct sg_table *sg_head, void *client_context,
+			   struct device  *dma_device);
+	void (*put_pages)(struct sg_table *sg_head, void *client_context);
+	unsigned long (*get_page_size)(void *client_context);
+	void (*release)(void *client_context);
+
+};
+
+typedef int (*invalidate_peer_memory)(void *reg_handle,
+					  void *core_context);
+
+void *ib_register_peer_memory_client(struct peer_memory_client *peer_client,
+				  invalidate_peer_memory *invalidate_callback);
+void ib_unregister_peer_memory_client(void *reg_handle);
+
+
+/*------------------- PeerDirect bridge driver ------------------------------*/
+
+#define AMD_PEER_BRIDGE_DRIVER_VERSION	"1.0"
+#define AMD_PEER_BRIDGE_DRIVER_NAME	"amdkfd"
+
+
+static void* (*pfn_ib_register_peer_memory_client)(struct peer_memory_client
+							*peer_client,
+					invalidate_peer_memory
+							*invalidate_callback);
+
+static void (*pfn_ib_unregister_peer_memory_client)(void *reg_handle);
+
+static const struct amd_rdma_interface *rdma_interface;
+
+static invalidate_peer_memory ib_invalidate_callback;
+static void *ib_reg_handle;
+
+struct amd_mem_context {
+	uint64_t	va;
+	uint64_t	size;
+	struct pid	*pid;
+
+	struct amd_p2p_info  *p2p_info;
+
+	/* Flag that free callback was called */
+	int free_callback_called;
+
+	/* Context received from PeerDirect call */
+	void *core_context;
+};
+
+
+static void free_callback(void *client_priv)
+{
+	struct amd_mem_context *mem_context =
+		(struct amd_mem_context *)client_priv;
+
+	pr_debug("free_callback: data 0x%p\n", mem_context);
+
+	if (!mem_context) {
+		pr_warn("free_callback: Invalid client context\n");
+		return;
+	}
+
+	pr_debug("mem_context->core_context 0x%p\n", mem_context->core_context);
+
+	/* Call back IB stack asking to invalidate memory */
+	(*ib_invalidate_callback) (ib_reg_handle, mem_context->core_context);
+
+	/* amdkfd will free resources when we return from this callback.
+	 * Set flag to inform that there is nothing to do on "put_pages", etc.
+	 */
+	ACCESS_ONCE(mem_context->free_callback_called) = 1;
+}
+
+
+static int amd_acquire(unsigned long addr, size_t size,
+			void *peer_mem_private_data,
+			char *peer_mem_name, void **client_context)
+{
+	int ret;
+	struct amd_mem_context *mem_context;
+	struct pid *pid;
+
+	/* Get pointer to structure describing current process */
+	pid = get_task_pid(current, PIDTYPE_PID);
+
+	pr_debug("acquire: addr:0x%lx,size:0x%x, pid 0x%p\n",
+					addr, (unsigned int)size, pid);
+
+	/* Check if address is handled by AMD GPU driver */
+	ret = rdma_interface->is_gpu_address(addr, pid);
+
+	if (!ret) {
+		pr_debug("acquire: Not GPU Address\n");
+		/* This is not GPU address */
+		return 0;
+	}
+
+	pr_debug("acquire: GPU address\n");
+
+	/* Initialize context used for operation with given address */
+	mem_context = kzalloc(sizeof(struct amd_mem_context), GFP_KERNEL);
+
+	if (!mem_context)
+		return 0;	/* Error case handled as not GPU address  */
+
+	mem_context->free_callback_called = 0;
+	mem_context->va   = addr;
+	mem_context->size = size;
+
+	/* Save PID. It is guaranteed that the function will be
+	 * called in the correct process context as opposite to others.
+	 */
+	mem_context->pid  = pid;
+
+	pr_debug("acquire: Client context %p\n", mem_context);
+
+	/* Return pointer to allocated context */
+	*client_context = mem_context;
+
+	/* Return 1 to inform that this address which will be handled
+	 * by AMD GPU driver
+	 */
+	return 1;
+}
+
+static int amd_get_pages(unsigned long addr, size_t size, int write, int force,
+			  struct sg_table *sg_head,
+			  void *client_context, void *core_context)
+{
+	int ret;
+	struct amd_mem_context *mem_context =
+		(struct amd_mem_context *)client_context;
+
+	pr_debug("get_pages: addr:0x%lx,size:0x%x, core_context:%p\n",
+		addr, (unsigned int)size, core_context);
+
+	if (!mem_context) {
+		pr_warn("get_pages: Invalid client context");
+		return -EINVAL;
+	}
+
+	pr_debug("get_pages: pid :0x%p\n", mem_context->pid);
+
+
+	if (addr != mem_context->va) {
+		pr_warn("get_pages: Context address (0x%llx) is not the same\n",
+			mem_context->va);
+		return -EINVAL;
+	}
+
+	if (size != mem_context->size) {
+		pr_warn("get_pages: Context size (0x%llx) is not the same\n",
+			mem_context->size);
+		return -EINVAL;
+	}
+
+	ret = rdma_interface->get_pages(addr,
+					size,
+					mem_context->pid,
+					&mem_context->p2p_info,
+					free_callback,
+					mem_context);
+
+	if (ret || !mem_context->p2p_info) {
+		pr_err("Could not rdma::get_pages failure: %d\n", ret);
+		return ret;
+	}
+
+	mem_context->core_context = core_context;
+
+	/* Note: At this stage it is OK not to fill sg_table */
+	return 0;
+}
+
+
+static int amd_dma_map(struct sg_table *sg_head, void *client_context,
+			struct device *dma_device, int dmasync, int *nmap)
+{
+	/*
+	 * NOTE/TODO:
+	 * We could have potentially three cases for real memory
+	 *	location:
+	 *		- all memory in the local
+	 *		- all memory in the system (RAM)
+	 *		- memory is spread (s/g) between local and system.
+	 *
+	 *	In the case of all memory in the system we could use
+	 *	iommu driver to build DMA addresses but not in the case
+	 *	of local memory because currently iommu driver doesn't
+	 *	deal with local/device memory addresses (it requires "struct
+	 *	page").
+	 *
+	 *	Accordingly returning assumes that iommu funcutionality
+	 *	should be disabled so we can assume that sg_table already
+	 *	contains DMA addresses.
+	 *
+	 */
+	struct amd_mem_context *mem_context =
+		(struct amd_mem_context *)client_context;
+
+	pr_debug("dma_map: Context 0x%p, sg_head 0x%p\n",
+			client_context, sg_head);
+
+	pr_debug("dma_map: pid 0x%p, address 0x%llx, size:0x%llx\n",
+			mem_context->pid,
+			mem_context->va,
+			mem_context->size);
+
+	if (!mem_context->p2p_info) {
+		pr_err("dma_map: No sg table were allocated\n");
+		return -EINVAL;
+	}
+
+	/* Copy information about previosly allocated sg_table */
+	*sg_head = *mem_context->p2p_info->pages;
+
+	/* Return number of pages */
+	*nmap = mem_context->p2p_info->pages->nents;
+
+	return 0;
+}
+
+static int amd_dma_unmap(struct sg_table *sg_head, void *client_context,
+			   struct device  *dma_device)
+{
+	struct amd_mem_context *mem_context =
+		(struct amd_mem_context *)client_context;
+
+	pr_debug("dma_unmap: Context 0x%p, sg_table 0x%p\n",
+			client_context, sg_head);
+
+	pr_debug("dma_unmap: pid 0x%p, address 0x%llx, size:0x%llx\n",
+			mem_context->pid,
+			mem_context->va,
+			mem_context->size);
+
+	/* Assume success */
+	return 0;
+}
+static void amd_put_pages(struct sg_table *sg_head, void *client_context)
+{
+	int ret = 0;
+	struct amd_mem_context *mem_context =
+		(struct amd_mem_context *)client_context;
+
+	pr_debug("put_pages: sg_head %p client_context: 0x%p\n",
+			sg_head, client_context);
+	pr_debug("put_pages: pid 0x%p, address 0x%llx, size:0x%llx\n",
+			mem_context->pid,
+			mem_context->va,
+			mem_context->size);
+
+	pr_debug("put_pages: mem_context->p2p_info %p\n",
+				mem_context->p2p_info);
+
+	if (ACCESS_ONCE(mem_context->free_callback_called)) {
+		pr_debug("put_pages: free callback was called\n");
+		return;
+	}
+
+	if (mem_context->p2p_info) {
+		ret = rdma_interface->put_pages(&mem_context->p2p_info);
+		mem_context->p2p_info = NULL;
+
+		if (ret)
+			pr_err("put_pages failure: %d (callback status %d)\n",
+					ret, mem_context->free_callback_called);
+	} else
+		pr_err("put_pages: Pointer to p2p info is null\n");
+}
+static unsigned long amd_get_page_size(void *client_context)
+{
+	unsigned long page_size;
+	int result;
+	struct amd_mem_context *mem_context =
+		(struct amd_mem_context *)client_context;
+
+	pr_debug("get_page_size: context: %p\n", client_context);
+	pr_debug("get_page_size: pid 0x%p, address 0x%llx, size:0x%llx\n",
+			mem_context->pid,
+			mem_context->va,
+			mem_context->size);
+
+
+	result = rdma_interface->get_page_size(
+				mem_context->va,
+				mem_context->size,
+				mem_context->pid,
+				&page_size);
+
+	if (result) {
+		pr_err("Could not get page size. %d\n", result);
+		/* If we failed to get page size then do not know what to do.
+		 * Let's return some default value
+		 */
+		return PAGE_SIZE;
+	}
+
+	return page_size;
+}
+
+static void amd_release(void *client_context)
+{
+	struct amd_mem_context *mem_context =
+		(struct amd_mem_context *)client_context;
+
+	pr_debug("release: context: 0x%p\n", client_context);
+	pr_debug("release: pid 0x%p, address 0x%llx, size:0x%llx\n",
+			mem_context->pid,
+			mem_context->va,
+			mem_context->size);
+
+	kfree(mem_context);
+}
+
+
+static struct peer_memory_client amd_mem_client = {
+	.acquire = amd_acquire,
+	.get_pages = amd_get_pages,
+	.dma_map = amd_dma_map,
+	.dma_unmap = amd_dma_unmap,
+	.put_pages = amd_put_pages,
+	.get_page_size = amd_get_page_size,
+	.release = amd_release,
+};
+
+
+int kfd_init_peer_direct(void)
+{
+	int result;
+
+	pr_debug("Try to initialize PeerDirect support\n");
+
+	pfn_ib_register_peer_memory_client =
+		(void *(*)(struct peer_memory_client *,
+			  invalidate_peer_memory *))
+		symbol_request(ib_register_peer_memory_client);
+
+	pfn_ib_unregister_peer_memory_client = (void (*)(void *))
+		symbol_request(ib_unregister_peer_memory_client);
+
+	if (!pfn_ib_register_peer_memory_client ||
+		!pfn_ib_unregister_peer_memory_client) {
+		pr_warn("amdkfd: PeerDirect interface was not detected\n");
+		return -EINVAL;
+	}
+
+	result = amdkfd_query_rdma_interface(&rdma_interface);
+
+	if (result < 0) {
+		pr_err("amdkfd: Cannot get RDMA Interface (result = %d)\n",
+				result);
+		return result;
+	}
+
+	strcpy(amd_mem_client.name,    AMD_PEER_BRIDGE_DRIVER_NAME);
+	strcpy(amd_mem_client.version, AMD_PEER_BRIDGE_DRIVER_VERSION);
+
+	ib_reg_handle = pfn_ib_register_peer_memory_client(&amd_mem_client,
+						&ib_invalidate_callback);
+
+	if (!ib_reg_handle) {
+		pr_err("amdkfd: Cannot register peer memory client\n");
+		return -EINVAL;
+	}
+
+	pr_info("amdkfd: PeerDirect support was initialized successfully\n");
+	return 0;
+}
+
+void kfd_close_peer_direct(void)
+{
+	if (pfn_ib_unregister_peer_memory_client) {
+		if (ib_reg_handle)
+			pfn_ib_unregister_peer_memory_client(ib_reg_handle);
+
+		symbol_put(ib_unregister_peer_memory_client);
+	}
+
+	if (pfn_ib_register_peer_memory_client)
+		symbol_put(ib_register_peer_memory_client);
+
+}
+
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_priv.h b/drivers/gpu/drm/amd/amdkfd/kfd_priv.h
index cfa2283..3ec7914 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_priv.h
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_priv.h
@@ -913,4 +913,9 @@ int restore(struct kfd_dev *kfd);
 #define KFD_MULTI_PROC_MAPPING_HWS_SUPPORT 600
 #define KFD_CWSR_CZ_FW_VER 625
 
+/* PeerDirect support */
+int kfd_init_peer_direct(void);
+void kfd_close_peer_direct(void);
+
+
 #endif
-- 
2.7.4