path: root/drivers/gpu/drm/nouveau/nouveau_svm.c

/*
 * Copyright 2018 Red Hat 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.
 */
#include "nouveau_svm.h"
#include "nouveau_drv.h"
#include "nouveau_chan.h"
#include "nouveau_dmem.h"

#include <nvif/event.h>
#include <nvif/object.h>
#include <nvif/vmm.h>

#include <nvif/class.h>
#include <nvif/clb069.h>
#include <nvif/ifc00d.h>

#include <linux/sched/mm.h>
#include <linux/sort.h>
#include <linux/hmm.h>
#include <linux/memremap.h>
#include <linux/rmap.h>

struct nouveau_svm {
	struct nouveau_drm *drm;
	struct mutex mutex;
	struct list_head inst;

	struct nouveau_svm_fault_buffer {
		int id;
		struct nvif_object object;
		u32 entries;
		u32 getaddr;
		u32 putaddr;
		u32 get;
		u32 put;
		struct nvif_event notify;
		struct work_struct work;

		struct nouveau_svm_fault {
			u64 inst;
			u64 addr;
			u64 time;
			u32 engine;
			u8  gpc;
			u8  hub;
			u8  access;
			u8  client;
			u8  fault;
			struct nouveau_svmm *svmm;
		} **fault;
		int fault_nr;
	} buffer[];
};

#define FAULT_ACCESS_READ 0
#define FAULT_ACCESS_WRITE 1
#define FAULT_ACCESS_ATOMIC 2
#define FAULT_ACCESS_PREFETCH 3

#define SVM_DBG(s,f,a...) NV_DEBUG((s)->drm, "svm: "f"\n", ##a)
#define SVM_ERR(s,f,a...) NV_WARN((s)->drm, "svm: "f"\n", ##a)

struct nouveau_pfnmap_args {
	struct nvif_ioctl_v0 i;
	struct nvif_ioctl_mthd_v0 m;
	struct nvif_vmm_pfnmap_v0 p;
};

struct nouveau_ivmm {
	struct nouveau_svmm *svmm;
	u64 inst;
	struct list_head head;
};

static struct nouveau_ivmm *
nouveau_ivmm_find(struct nouveau_svm *svm, u64 inst)
{
	struct nouveau_ivmm *ivmm;
	list_for_each_entry(ivmm, &svm->inst, head) {
		if (ivmm->inst == inst)
			return ivmm;
	}
	return NULL;
}

#define SVMM_DBG(s,f,a...)                                                     \
	NV_DEBUG((s)->vmm->cli->drm, "svm-%p: "f"\n", (s), ##a)
#define SVMM_ERR(s,f,a...)                                                     \
	NV_WARN((s)->vmm->cli->drm, "svm-%p: "f"\n", (s), ##a)

int
nouveau_svmm_bind(struct drm_device *dev, void *data,
		  struct drm_file *file_priv)
{
	struct nouveau_cli *cli = nouveau_cli(file_priv);
	struct drm_nouveau_svm_bind *args = data;
	unsigned target, cmd, priority;
	unsigned long addr, end;
	struct mm_struct *mm;

	args->va_start &= PAGE_MASK;
	args->va_end = ALIGN(args->va_end, PAGE_SIZE);

	/* Sanity check arguments */
	if (args->reserved0 || args->reserved1)
		return -EINVAL;
	if (args->header & (~NOUVEAU_SVM_BIND_VALID_MASK))
		return -EINVAL;
	if (args->va_start >= args->va_end)
		return -EINVAL;

	cmd = args->header >> NOUVEAU_SVM_BIND_COMMAND_SHIFT;
	cmd &= NOUVEAU_SVM_BIND_COMMAND_MASK;
	switch (cmd) {
	case NOUVEAU_SVM_BIND_COMMAND__MIGRATE:
		break;
	default:
		return -EINVAL;
	}

	priority = args->header >> NOUVEAU_SVM_BIND_PRIORITY_SHIFT;
	priority &= NOUVEAU_SVM_BIND_PRIORITY_MASK;

	/* FIXME support CPU target ie all target value < GPU_VRAM */
	target = args->header >> NOUVEAU_SVM_BIND_TARGET_SHIFT;
	target &= NOUVEAU_SVM_BIND_TARGET_MASK;
	switch (target) {
	case NOUVEAU_SVM_BIND_TARGET__GPU_VRAM:
		break;
	default:
		return -EINVAL;
	}

	/*
	 * FIXME: For now refuse non 0 stride, we need to change the migrate
	 * kernel function to handle stride to avoid to create a mess within
	 * each device driver.
	 */
	if (args->stride)
		return -EINVAL;

	/*
	 * Ok we are ask to do something sane, for now we only support migrate
	 * commands but we will add things like memory policy (what to do on
	 * page fault) and maybe some other commands.
	 */

	mm = get_task_mm(current);
	if (!mm) {
		return -EINVAL;
	}
	mmap_read_lock(mm);

	if (!cli->svm.svmm) {
		mmap_read_unlock(mm);
		mmput(mm);
		return -EINVAL;
	}

	for (addr = args->va_start, end = args->va_end; addr < end;) {
		struct vm_area_struct *vma;
		unsigned long next;

		vma = find_vma_intersection(mm, addr, end);
		if (!vma)
			break;

		addr = max(addr, vma->vm_start);
		next = min(vma->vm_end, end);
		/* This is a best effort so we ignore errors */
		nouveau_dmem_migrate_vma(cli->drm, cli->svm.svmm, vma, addr,
					 next);
		addr = next;
	}

	/*
	 * FIXME Return the number of page we have migrated, again we need to
	 * update the migrate API to return that information so that we can