blob: 9b9c2b9bf2ef089a81775bece991f65a990dd5dc [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0 OR MIT
/*
* Copyright 2020-2021 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.
*/
#include <linux/types.h>
#include <linux/hmm.h>
#include <linux/dma-direction.h>
#include <linux/dma-mapping.h>
#include "amdgpu_sync.h"
#include "amdgpu_object.h"
#include "amdgpu_vm.h"
#include "amdgpu_mn.h"
#include "amdgpu_res_cursor.h"
#include "kfd_priv.h"
#include "kfd_svm.h"
#include "kfd_migrate.h"
#ifdef dev_fmt
#undef dev_fmt
#endif
#define dev_fmt(fmt) "kfd_migrate: %s: " fmt, __func__
static uint64_t
svm_migrate_direct_mapping_addr(struct amdgpu_device *adev, uint64_t addr)
{
return addr + amdgpu_ttm_domain_start(adev, TTM_PL_VRAM);
}
static int
svm_migrate_gart_map(struct amdgpu_ring *ring, uint64_t npages,
dma_addr_t *addr, uint64_t *gart_addr, uint64_t flags)
{
struct amdgpu_device *adev = ring->adev;
struct amdgpu_job *job;
unsigned int num_dw, num_bytes;
struct dma_fence *fence;
uint64_t src_addr, dst_addr;
uint64_t pte_flags;
void *cpu_addr;
int r;
/* use gart window 0 */
*gart_addr = adev->gmc.gart_start;
num_dw = ALIGN(adev->mman.buffer_funcs->copy_num_dw, 8);
num_bytes = npages * 8;
r = amdgpu_job_alloc_with_ib(adev, num_dw * 4 + num_bytes,
AMDGPU_IB_POOL_DELAYED, &job);
if (r)
return r;
src_addr = num_dw * 4;
src_addr += job->ibs[0].gpu_addr;
dst_addr = amdgpu_bo_gpu_offset(adev->gart.bo);
amdgpu_emit_copy_buffer(adev, &job->ibs[0], src_addr,
dst_addr, num_bytes, false);
amdgpu_ring_pad_ib(ring, &job->ibs[0]);
WARN_ON(job->ibs[0].length_dw > num_dw);
pte_flags = AMDGPU_PTE_VALID | AMDGPU_PTE_READABLE;
pte_flags |= AMDGPU_PTE_SYSTEM | AMDGPU_PTE_SNOOPED;
if (!(flags & KFD_IOCTL_SVM_FLAG_GPU_RO))
pte_flags |= AMDGPU_PTE_WRITEABLE;
pte_flags |= adev->gart.gart_pte_flags;
cpu_addr = &job->ibs[0].ptr[num_dw];
r = amdgpu_gart_map(adev, 0, npages, addr, pte_flags, cpu_addr);
if (r)
goto error_free;
r = amdgpu_job_submit(job, &adev->mman.entity,
AMDGPU_FENCE_OWNER_UNDEFINED, &fence);
if (r)
goto error_free;
dma_fence_put(fence);
return r;
error_free:
amdgpu_job_free(job);
return r;
}
/**
* svm_migrate_copy_memory_gart - sdma copy data between ram and vram
*
* @adev: amdgpu device the sdma ring running
* @src: source page address array
* @dst: destination page address array
* @npages: number of pages to copy
* @direction: enum MIGRATION_COPY_DIR
* @mfence: output, sdma fence to signal after sdma is done
*
* ram address uses GART table continuous entries mapping to ram pages,
* vram address uses direct mapping of vram pages, which must have npages
* number of continuous pages.
* GART update and sdma uses same buf copy function ring, sdma is splited to
* multiple GTT_MAX_PAGES transfer, all sdma operations are serialized, wait for
* the last sdma finish fence which is returned to check copy memory is done.
*
* Context: Process context, takes and releases gtt_window_lock
*
* Return:
* 0 - OK, otherwise error code
*/
static int
svm_migrate_copy_memory_gart(struct amdgpu_device *adev, dma_addr_t *sys,
uint64_t *vram, uint64_t npages,
enum MIGRATION_COPY_DIR direction,
struct dma_fence **mfence)
{
const uint64_t GTT_MAX_PAGES = AMDGPU_GTT_MAX_TRANSFER_SIZE;
struct amdgpu_ring *ring = adev->mman.buffer_funcs_ring;
uint64_t gart_s, gart_d;
struct dma_fence *next;
uint64_t size;
int r;
mutex_lock(&adev->mman.gtt_window_lock);
while (npages) {
size = min(GTT_MAX_PAGES, npages);
if (direction == FROM_VRAM_TO_RAM) {
gart_s = svm_migrate_direct_mapping_addr(adev, *vram);
r = svm_migrate_gart_map(ring, size, sys, &gart_d, 0);
} else if (direction == FROM_RAM_TO_VRAM) {
r = svm_migrate_gart_map(ring, size, sys, &gart_s,
KFD_IOCTL_SVM_FLAG_GPU_RO);
gart_d = svm_migrate_direct_mapping_addr(adev, *vram);
}
if (r) {
dev_err(adev->dev, "fail %d create gart mapping\n", r);
goto out_unlock;
}
r = amdgpu_copy_buffer(ring, gart_s, gart_d, size * PAGE_SIZE,
NULL, &next, false, true, false);
if (r) {
dev_err(adev->dev, "fail %d to copy memory\n", r);
goto out_unlock;
}
dma_fence_put(*mfence);
*mfence = next;
npages -= size;
if (npages) {
sys += size;
vram += size;
}
}
out_unlock:
mutex_unlock(&adev->mman.gtt_window_lock);
return r;
}
/**
* svm_migrate_copy_done - wait for memory copy sdma is done
*
* @adev: amdgpu device the sdma memory copy is executing on
* @mfence: migrate fence
*
* Wait for dma fence is signaled, if the copy ssplit into multiple sdma
* operations, this is the last sdma operation fence.
*
* Context: called after svm_migrate_copy_memory
*
* Return:
* 0 - success
* otherwise - error code from dma fence signal
*/
static int
svm_migrate_copy_done(struct amdgpu_device *adev, struct dma_fence *mfence)
{
int r = 0;
if (mfence) {
r = dma_fence_wait(mfence, false);
dma_fence_put(mfence);
pr_debug("sdma copy memory fence done\n");
}
return r;
}
unsigned long
svm_migrate_addr_to_pfn(struct amdgpu_device *adev, unsigned long addr)
{
return (addr + adev->kfd.dev->pgmap.range.start) >> PAGE_SHIFT;
}
static void
svm_migrate_get_vram_page(struct svm_range *prange, unsigned long pfn)
{
struct page *page;
page = pfn_to_page(pfn);
svm_range_bo_ref(prange->svm_bo);
page->zone_device_data = prange->svm_bo;
get_page(page);
lock_page(page);
}
static void
svm_migrate_put_vram_page(struct amdgpu_device *adev, unsigned long addr)
{
struct page *page;
page = pfn_to_page(svm_migrate_addr_to_pfn(adev, addr));
unlock_page(page);
put_page(page);
}
static unsigned long
svm_migrate_addr(struct amdgpu_device *adev, struct page *page)
{
unsigned long addr;
addr = page_to_pfn(page) << PAGE_SHIFT;
return (addr - adev->kfd.dev->pgmap.range.start);
}
static struct page *
svm_migrate_get_sys_page(struct vm_area_struct *vma, unsigned long addr)
{
struct page *page;
page = alloc_page_vma(GFP_HIGHUSER, vma, addr);
if (page)
lock_page(page);
return page;
}
static void svm_migrate_put_sys_page(unsigned long addr)
{
struct page *page;
page = pfn_to_page(addr >> PAGE_SHIFT);
unlock_page(page);
put_page(page);
}
static unsigned long svm_migrate_successful_pages(struct migrate_vma *migrate)
{
unsigned long cpages = 0;
unsigned long i;
for (i = 0; i < migrate->npages; i++) {
if (migrate->src[i] & MIGRATE_PFN_VALID &&
migrate->src[i] & MIGRATE_PFN_MIGRATE)
cpages++;
}
return cpages;
}
static unsigned long svm_migrate_unsuccessful_pages(struct migrate_vma *migrate)
{
unsigned long upages = 0;
unsigned long i;
for (i = 0; i < migrate->npages; i++) {
if (migrate->src[i] & MIGRATE_PFN_VALID &&
!(migrate->src[i] & MIGRATE_PFN_MIGRATE))
upages++;
}
return upages;
}
static int
svm_migrate_copy_to_vram(struct amdgpu_device *adev, struct svm_range *prange,
struct migrate_vma *migrate, struct dma_fence **mfence,
dma_addr_t *scratch)
{
uint64_t npages = migrate->cpages;
struct device *dev = adev->dev;
struct amdgpu_res_cursor cursor;
dma_addr_t *src;
uint64_t *dst;
uint64_t i, j;
int r;
pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms, prange->start,
prange->last);
src = scratch;
dst = (uint64_t *)(scratch + npages);
r = svm_range_vram_node_new(adev, prange, true);
if (r) {
dev_err(adev->dev, "fail %d to alloc vram\n", r);
goto out;
}
amdgpu_res_first(prange->ttm_res, prange->offset << PAGE_SHIFT,
npages << PAGE_SHIFT, &cursor);
for (i = j = 0; i < npages; i++) {
struct page *spage;
spage = migrate_pfn_to_page(migrate->src[i]);
if (spage && !is_zone_device_page(spage)) {
dst[i] = cursor.start + (j << PAGE_SHIFT);
migrate->dst[i] = svm_migrate_addr_to_pfn(adev, dst[i]);
svm_migrate_get_vram_page(prange, migrate->dst[i]);
migrate->dst[i] = migrate_pfn(migrate->dst[i]);
src[i] = dma_map_page(dev, spage, 0, PAGE_SIZE,
DMA_TO_DEVICE);
r = dma_mapping_error(dev, src[i]);
if (r) {
dev_err(adev->dev, "fail %d dma_map_page\n", r);
goto out_free_vram_pages;
}
} else {
if (j) {
r = svm_migrate_copy_memory_gart(
adev, src + i - j,
dst + i - j, j,
FROM_RAM_TO_VRAM,
mfence);
if (r)
goto out_free_vram_pages;
amdgpu_res_next(&cursor, j << PAGE_SHIFT);
j = 0;
} else {
amdgpu_res_next(&cursor, PAGE_SIZE);
}
continue;
}
pr_debug_ratelimited("dma mapping src to 0x%llx, pfn 0x%lx\n",
src[i] >> PAGE_SHIFT, page_to_pfn(spage));
if (j >= (cursor.size >> PAGE_SHIFT) - 1 && i < npages - 1) {
r = svm_migrate_copy_memory_gart(adev, src + i - j,
dst + i - j, j + 1,
FROM_RAM_TO_VRAM,
mfence);
if (r)
goto out_free_vram_pages;
amdgpu_res_next(&cursor, (j + 1) * PAGE_SIZE);
j= 0;
} else {
j++;
}
}
r = svm_migrate_copy_memory_gart(adev, src + i - j, dst + i - j, j,
FROM_RAM_TO_VRAM, mfence);
out_free_vram_pages:
if (r) {
pr_debug("failed %d to copy memory to vram\n", r);
while (i--) {
svm_migrate_put_vram_page(adev, dst[i]);
migrate->dst[i] = 0;
}
}
#ifdef DEBUG_FORCE_MIXED_DOMAINS
for (i = 0, j = 0; i < npages; i += 4, j++) {
if (j & 1)
continue;
svm_migrate_put_vram_page(adev, dst[i]);
migrate->dst[i] = 0;
svm_migrate_put_vram_page(adev, dst[i + 1]);
migrate->dst[i + 1] = 0;
svm_migrate_put_vram_page(adev, dst[i + 2]);
migrate->dst[i + 2] = 0;
svm_migrate_put_vram_page(adev, dst[i + 3]);
migrate->dst[i + 3] = 0;
}
#endif
out:
return r;
}
static long
svm_migrate_vma_to_vram(struct amdgpu_device *adev, struct svm_range *prange,
struct vm_area_struct *vma, uint64_t start,
uint64_t end)
{
uint64_t npages = (end - start) >> PAGE_SHIFT;
struct kfd_process_device *pdd;
struct dma_fence *mfence = NULL;
struct migrate_vma migrate;
unsigned long cpages = 0;
dma_addr_t *scratch;
size_t size;
void *buf;
int r = -ENOMEM;
memset(&migrate, 0, sizeof(migrate));
migrate.vma = vma;
migrate.start = start;
migrate.end = end;
migrate.flags = MIGRATE_VMA_SELECT_SYSTEM;
migrate.pgmap_owner = SVM_ADEV_PGMAP_OWNER(adev);
size = 2 * sizeof(*migrate.src) + sizeof(uint64_t) + sizeof(dma_addr_t);
size *= npages;
buf = kvmalloc(size, GFP_KERNEL | __GFP_ZERO);
if (!buf)
goto out;
migrate.src = buf;
migrate.dst = migrate.src + npages;
scratch = (dma_addr_t *)(migrate.dst + npages);
r = migrate_vma_setup(&migrate);
if (r) {
dev_err(adev->dev, "vma setup fail %d range [0x%lx 0x%lx]\n", r,
prange->start, prange->last);
goto out_free;
}
cpages = migrate.cpages;
if (!cpages) {
pr_debug("failed collect migrate sys pages [0x%lx 0x%lx]\n",
prange->start, prange->last);
goto out_free;
}
if (cpages != npages)
pr_debug("partial migration, 0x%lx/0x%llx pages migrated\n",
cpages, npages);
else
pr_debug("0x%lx pages migrated\n", cpages);
r = svm_migrate_copy_to_vram(adev, prange, &migrate, &mfence, scratch);
migrate_vma_pages(&migrate);
pr_debug("successful/cpages/npages 0x%lx/0x%lx/0x%lx\n",
svm_migrate_successful_pages(&migrate), cpages, migrate.npages);
svm_migrate_copy_done(adev, mfence);
migrate_vma_finalize(&migrate);
svm_range_dma_unmap(adev->dev, scratch, 0, npages);
svm_range_free_dma_mappings(prange);
out_free:
kvfree(buf);
out:
if (!r && cpages) {
pdd = svm_range_get_pdd_by_adev(prange, adev);
if (pdd)
WRITE_ONCE(pdd->page_in, pdd->page_in + cpages);
return cpages;
}
return r;
}
/**
* svm_migrate_ram_to_vram - migrate svm range from system to device
* @prange: range structure
* @best_loc: the device to migrate to
* @mm: the process mm structure
*
* Context: Process context, caller hold mmap read lock, svms lock, prange lock
*
* Return:
* 0 - OK, otherwise error code
*/
static int
svm_migrate_ram_to_vram(struct svm_range *prange, uint32_t best_loc,
struct mm_struct *mm)
{
unsigned long addr, start, end;
struct vm_area_struct *vma;
struct amdgpu_device *adev;
unsigned long cpages = 0;
long r = 0;
if (prange->actual_loc == best_loc) {
pr_debug("svms 0x%p [0x%lx 0x%lx] already on best_loc 0x%x\n",
prange->svms, prange->start, prange->last, best_loc);
return 0;
}
adev = svm_range_get_adev_by_id(prange, best_loc);
if (!adev) {
pr_debug("failed to get device by id 0x%x\n", best_loc);
return -ENODEV;
}
pr_debug("svms 0x%p [0x%lx 0x%lx] to gpu 0x%x\n", prange->svms,
prange->start, prange->last, best_loc);
/* FIXME: workaround for page locking bug with invalid pages */
svm_range_prefault(prange, mm, SVM_ADEV_PGMAP_OWNER(adev));
start = prange->start << PAGE_SHIFT;
end = (prange->last + 1) << PAGE_SHIFT;
for (addr = start; addr < end;) {
unsigned long next;
vma = find_vma(mm, addr);
if (!vma || addr < vma->vm_start)
break;
next = min(vma->vm_end, end);
r = svm_migrate_vma_to_vram(adev, prange, vma, addr, next);
if (r < 0) {
pr_debug("failed %ld to migrate\n", r);
break;
} else {
cpages += r;
}
addr = next;
}
if (cpages)
prange->actual_loc = best_loc;
return r < 0 ? r : 0;
}
static void svm_migrate_page_free(struct page *page)
{
struct svm_range_bo *svm_bo = page->zone_device_data;
if (svm_bo) {
pr_debug_ratelimited("ref: %d\n", kref_read(&svm_bo->kref));
svm_range_bo_unref(svm_bo);
}
}
static int
svm_migrate_copy_to_ram(struct amdgpu_device *adev, struct svm_range *prange,
struct migrate_vma *migrate, struct dma_fence **mfence,
dma_addr_t *scratch, uint64_t npages)
{
struct device *dev = adev->dev;
uint64_t *src;
dma_addr_t *dst;
struct page *dpage;
uint64_t i = 0, j;
uint64_t addr;
int r = 0;
pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms, prange->start,
prange->last);
addr = prange->start << PAGE_SHIFT;
src = (uint64_t *)(scratch + npages);
dst = scratch;
for (i = 0, j = 0; i < npages; i++, addr += PAGE_SIZE) {
struct page *spage;
spage = migrate_pfn_to_page(migrate->src[i]);
if (!spage || !is_zone_device_page(spage)) {
pr_debug("invalid page. Could be in CPU already svms 0x%p [0x%lx 0x%lx]\n",
prange->svms, prange->start, prange->last);
if (j) {
r = svm_migrate_copy_memory_gart(adev, dst + i - j,
src + i - j, j,
FROM_VRAM_TO_RAM,
mfence);
if (r)
goto out_oom;
j = 0;
}
continue;
}
src[i] = svm_migrate_addr(adev, spage);
if (i > 0 && src[i] != src[i - 1] + PAGE_SIZE) {
r = svm_migrate_copy_memory_gart(adev, dst + i - j,
src + i - j, j,
FROM_VRAM_TO_RAM,
mfence);
if (r)
goto out_oom;
j = 0;
}
dpage = svm_migrate_get_sys_page(migrate->vma, addr);
if (!dpage) {
pr_debug("failed get page svms 0x%p [0x%lx 0x%lx]\n",
prange->svms, prange->start, prange->last);
r = -ENOMEM;
goto out_oom;
}
dst[i] = dma_map_page(dev, dpage, 0, PAGE_SIZE, DMA_FROM_DEVICE);
r = dma_mapping_error(dev, dst[i]);
if (r) {
dev_err(adev->dev, "fail %d dma_map_page\n", r);
goto out_oom;
}
pr_debug_ratelimited("dma mapping dst to 0x%llx, pfn 0x%lx\n",
dst[i] >> PAGE_SHIFT, page_to_pfn(dpage));
migrate->dst[i] = migrate_pfn(page_to_pfn(dpage));
j++;
}
r = svm_migrate_copy_memory_gart(adev, dst + i - j, src + i - j, j,
FROM_VRAM_TO_RAM, mfence);
out_oom:
if (r) {
pr_debug("failed %d copy to ram\n", r);
while (i--) {
svm_migrate_put_sys_page(dst[i]);
migrate->dst[i] = 0;
}
}
return r;
}
static long
svm_migrate_vma_to_ram(struct amdgpu_device *adev, struct svm_range *prange,
struct vm_area_struct *vma, uint64_t start, uint64_t end)
{
uint64_t npages = (end - start) >> PAGE_SHIFT;
unsigned long upages = npages;
unsigned long cpages = 0;
struct kfd_process_device *pdd;
struct dma_fence *mfence = NULL;
struct migrate_vma migrate;
dma_addr_t *scratch;
size_t size;
void *buf;
int r = -ENOMEM;
memset(&migrate, 0, sizeof(migrate));
migrate.vma = vma;
migrate.start = start;
migrate.end = end;
migrate.flags = MIGRATE_VMA_SELECT_DEVICE_PRIVATE;
migrate.pgmap_owner = SVM_ADEV_PGMAP_OWNER(adev);
size = 2 * sizeof(*migrate.src) + sizeof(uint64_t) + sizeof(dma_addr_t);
size *= npages;
buf = kvmalloc(size, GFP_KERNEL | __GFP_ZERO);
if (!buf)
goto out;
migrate.src = buf;
migrate.dst = migrate.src + npages;
scratch = (dma_addr_t *)(migrate.dst + npages);
r = migrate_vma_setup(&migrate);
if (r) {
dev_err(adev->dev, "vma setup fail %d range [0x%lx 0x%lx]\n", r,
prange->start, prange->last);
goto out_free;
}
cpages = migrate.cpages;
if (!cpages) {
pr_debug("failed collect migrate device pages [0x%lx 0x%lx]\n",
prange->start, prange->last);
upages = svm_migrate_unsuccessful_pages(&migrate);
goto out_free;
}
if (cpages != npages)
pr_debug("partial migration, 0x%lx/0x%llx pages migrated\n",
cpages, npages);
else
pr_debug("0x%lx pages migrated\n", cpages);
r = svm_migrate_copy_to_ram(adev, prange, &migrate, &mfence,
scratch, npages);
migrate_vma_pages(&migrate);
upages = svm_migrate_unsuccessful_pages(&migrate);
pr_debug("unsuccessful/cpages/npages 0x%lx/0x%lx/0x%lx\n",
upages, cpages, migrate.npages);
svm_migrate_copy_done(adev, mfence);
migrate_vma_finalize(&migrate);
svm_range_dma_unmap(adev->dev, scratch, 0, npages);
out_free:
kvfree(buf);
out:
if (!r && cpages) {
pdd = svm_range_get_pdd_by_adev(prange, adev);
if (pdd)
WRITE_ONCE(pdd->page_out, pdd->page_out + cpages);
return upages;
}
return r ? r : upages;
}
/**
* svm_migrate_vram_to_ram - migrate svm range from device to system
* @prange: range structure
* @mm: process mm, use current->mm if NULL
*
* Context: Process context, caller hold mmap read lock, svms lock, prange lock
*
* Return:
* 0 - OK, otherwise error code
*/
int svm_migrate_vram_to_ram(struct svm_range *prange, struct mm_struct *mm)
{
struct amdgpu_device *adev;
struct vm_area_struct *vma;
unsigned long addr;
unsigned long start;
unsigned long end;
unsigned long upages = 0;
long r = 0;
if (!prange->actual_loc) {
pr_debug("[0x%lx 0x%lx] already migrated to ram\n",
prange->start, prange->last);
return 0;
}
adev = svm_range_get_adev_by_id(prange, prange->actual_loc);
if (!adev) {
pr_debug("failed to get device by id 0x%x\n",
prange->actual_loc);
return -ENODEV;
}
pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] from gpu 0x%x to ram\n",
prange->svms, prange, prange->start, prange->last,
prange->actual_loc);
start = prange->start << PAGE_SHIFT;
end = (prange->last + 1) << PAGE_SHIFT;
for (addr = start; addr < end;) {
unsigned long next;
vma = find_vma(mm, addr);
if (!vma || addr < vma->vm_start)
break;
next = min(vma->vm_end, end);
r = svm_migrate_vma_to_ram(adev, prange, vma, addr, next);
if (r < 0) {
pr_debug("failed %ld to migrate\n", r);
break;
} else {
upages += r;
}
addr = next;
}
if (!upages) {
svm_range_vram_node_free(prange);
prange->actual_loc = 0;
}
return r < 0 ? r : 0;
}
/**
* svm_migrate_vram_to_vram - migrate svm range from device to device
* @prange: range structure
* @best_loc: the device to migrate to
* @mm: process mm, use current->mm if NULL
*
* Context: Process context, caller hold mmap read lock, svms lock, prange lock
*
* Return:
* 0 - OK, otherwise error code
*/
static int
svm_migrate_vram_to_vram(struct svm_range *prange, uint32_t best_loc,
struct mm_struct *mm)
{
int r, retries = 3;
/*
* TODO: for both devices with PCIe large bar or on same xgmi hive, skip
* system memory as migration bridge
*/
pr_debug("from gpu 0x%x to gpu 0x%x\n", prange->actual_loc, best_loc);
do {
r = svm_migrate_vram_to_ram(prange, mm);
if (r)
return r;
} while (prange->actual_loc && --retries);
if (prange->actual_loc)
return -EDEADLK;
return svm_migrate_ram_to_vram(prange, best_loc, mm);
}
int
svm_migrate_to_vram(struct svm_range *prange, uint32_t best_loc,
struct mm_struct *mm)
{
if (!prange->actual_loc)
return svm_migrate_ram_to_vram(prange, best_loc, mm);
else
return svm_migrate_vram_to_vram(prange, best_loc, mm);
}
/**
* svm_migrate_to_ram - CPU page fault handler
* @vmf: CPU vm fault vma, address
*
* Context: vm fault handler, caller holds the mmap read lock
*
* Return:
* 0 - OK
* VM_FAULT_SIGBUS - notice application to have SIGBUS page fault
*/
static vm_fault_t svm_migrate_to_ram(struct vm_fault *vmf)
{
unsigned long addr = vmf->address;
struct vm_area_struct *vma;
enum svm_work_list_ops op;
struct svm_range *parent;
struct svm_range *prange;
struct kfd_process *p;
struct mm_struct *mm;
int r = 0;
vma = vmf->vma;
mm = vma->vm_mm;
p = kfd_lookup_process_by_mm(vma->vm_mm);
if (!p) {
pr_debug("failed find process at fault address 0x%lx\n", addr);
return VM_FAULT_SIGBUS;
}
if (READ_ONCE(p->svms.faulting_task) == current) {
pr_debug("skipping ram migration\n");
kfd_unref_process(p);
return 0;
}
addr >>= PAGE_SHIFT;
pr_debug("CPU page fault svms 0x%p address 0x%lx\n", &p->svms, addr);
mutex_lock(&p->svms.lock);
prange = svm_range_from_addr(&p->svms, addr, &parent);
if (!prange) {
pr_debug("cannot find svm range at 0x%lx\n", addr);
r = -EFAULT;
goto out;
}
mutex_lock(&parent->migrate_mutex);
if (prange != parent)
mutex_lock_nested(&prange->migrate_mutex, 1);
if (!prange->actual_loc)
goto out_unlock_prange;
svm_range_lock(parent);
if (prange != parent)
mutex_lock_nested(&prange->lock, 1);
r = svm_range_split_by_granularity(p, mm, addr, parent, prange);
if (prange != parent)
mutex_unlock(&prange->lock);
svm_range_unlock(parent);
if (r) {
pr_debug("failed %d to split range by granularity\n", r);
goto out_unlock_prange;
}
r = svm_migrate_vram_to_ram(prange, mm);
if (r)
pr_debug("failed %d migrate 0x%p [0x%lx 0x%lx] to ram\n", r,
prange, prange->start, prange->last);
/* xnack on, update mapping on GPUs with ACCESS_IN_PLACE */
if (p->xnack_enabled && parent == prange)
op = SVM_OP_UPDATE_RANGE_NOTIFIER_AND_MAP;
else
op = SVM_OP_UPDATE_RANGE_NOTIFIER;
svm_range_add_list_work(&p->svms, parent, mm, op);
schedule_deferred_list_work(&p->svms);
out_unlock_prange:
if (prange != parent)
mutex_unlock(&prange->migrate_mutex);
mutex_unlock(&parent->migrate_mutex);
out:
mutex_unlock(&p->svms.lock);
kfd_unref_process(p);
pr_debug("CPU fault svms 0x%p address 0x%lx done\n", &p->svms, addr);
return r ? VM_FAULT_SIGBUS : 0;
}
static const struct dev_pagemap_ops svm_migrate_pgmap_ops = {
.page_free = svm_migrate_page_free,
.migrate_to_ram = svm_migrate_to_ram,
};
/* Each VRAM page uses sizeof(struct page) on system memory */
#define SVM_HMM_PAGE_STRUCT_SIZE(size) ((size)/PAGE_SIZE * sizeof(struct page))
int svm_migrate_init(struct amdgpu_device *adev)
{
struct kfd_dev *kfddev = adev->kfd.dev;
struct dev_pagemap *pgmap;
struct resource *res;
unsigned long size;
void *r;
/* Page migration works on Vega10 or newer */
if (kfddev->device_info->asic_family < CHIP_VEGA10)
return -EINVAL;
pgmap = &kfddev->pgmap;
memset(pgmap, 0, sizeof(*pgmap));
/* TODO: register all vram to HMM for now.
* should remove reserved size
*/
size = ALIGN(adev->gmc.real_vram_size, 2ULL << 20);
res = devm_request_free_mem_region(adev->dev, &iomem_resource, size);
if (IS_ERR(res))
return -ENOMEM;
pgmap->type = MEMORY_DEVICE_PRIVATE;
pgmap->nr_range = 1;
pgmap->range.start = res->start;
pgmap->range.end = res->end;
pgmap->ops = &svm_migrate_pgmap_ops;
pgmap->owner = SVM_ADEV_PGMAP_OWNER(adev);
pgmap->flags = MIGRATE_VMA_SELECT_DEVICE_PRIVATE;
/* Device manager releases device-specific resources, memory region and
* pgmap when driver disconnects from device.
*/
r = devm_memremap_pages(adev->dev, pgmap);
if (IS_ERR(r)) {
pr_err("failed to register HMM device memory\n");
/* Disable SVM support capability */
pgmap->type = 0;
devm_release_mem_region(adev->dev, res->start, resource_size(res));
return PTR_ERR(r);
}
pr_debug("reserve %ldMB system memory for VRAM pages struct\n",
SVM_HMM_PAGE_STRUCT_SIZE(size) >> 20);
amdgpu_amdkfd_reserve_system_mem(SVM_HMM_PAGE_STRUCT_SIZE(size));
pr_info("HMM registered %ldMB device memory\n", size >> 20);
return 0;
}