The patch titled
Subject: nouveau/dmem: refactor nouveau_dmem_fault_copy_one()
has been added to the -mm mm-unstable branch. Its filename is
nouveau-dmem-refactor-nouveau_dmem_fault_copy_one.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/nouveau-dmem-refactor-nouveau_dmem_fault_copy_one.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Alistair Popple <apopple@xxxxxxxxxx>
Subject: nouveau/dmem: refactor nouveau_dmem_fault_copy_one()
Date: Wed, 28 Sep 2022 22:01:20 +1000
nouveau_dmem_fault_copy_one() is used during handling of CPU faults via
the migrate_to_ram() callback and is used to copy data from GPU to CPU
memory. It is currently specific to fault handling, however a future
patch implementing eviction of data during teardown needs similar
functionality.
Refactor out the core functionality so that it is not specific to fault
handling.
Link: https://lkml.kernel.org/r/20573d7b4e641a78fde9935f948e64e71c9e709e.1664366292.git-series.apopple@xxxxxxxxxx
Signed-off-by: Alistair Popple <apopple@xxxxxxxxxx>
Reviewed-by: Lyude Paul <lyude@xxxxxxxxxx>
Cc: Ben Skeggs <bskeggs@xxxxxxxxxx>
Cc: Ralph Campbell <rcampbell@xxxxxxxxxx>
Cc: John Hubbard <jhubbard@xxxxxxxxxx>
Cc: Alex Deucher <alexander.deucher@xxxxxxx>
Cc: Alex Sierra <alex.sierra@xxxxxxx>
Cc: Christian König <christian.koenig@xxxxxxx>
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Felix Kuehling <Felix.Kuehling@xxxxxxx>
Cc: "Huang, Ying" <ying.huang@xxxxxxxxx>
Cc: Jason Gunthorpe <jgg@xxxxxxxxxx>
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Yang Shi <shy828301@xxxxxxxxx>
Cc: Zi Yan <ziy@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
--- a/drivers/gpu/drm/nouveau/nouveau_dmem.c~nouveau-dmem-refactor-nouveau_dmem_fault_copy_one
+++ a/drivers/gpu/drm/nouveau/nouveau_dmem.c
@@ -139,44 +139,24 @@ static void nouveau_dmem_fence_done(stru
}
}
-static vm_fault_t nouveau_dmem_fault_copy_one(struct nouveau_drm *drm,
- struct vm_fault *vmf, struct migrate_vma *args,
- dma_addr_t *dma_addr)
+static int nouveau_dmem_copy_one(struct nouveau_drm *drm, struct page *spage,
+ struct page *dpage, dma_addr_t *dma_addr)
{
struct device *dev = drm->dev->dev;
- struct page *dpage, *spage;
- struct nouveau_svmm *svmm;
-
- spage = migrate_pfn_to_page(args->src[0]);
- if (!spage || !(args->src[0] & MIGRATE_PFN_MIGRATE))
- return 0;
- dpage = alloc_page_vma(GFP_HIGHUSER, vmf->vma, vmf->address);
- if (!dpage)
- return VM_FAULT_SIGBUS;
lock_page(dpage);
*dma_addr = dma_map_page(dev, dpage, 0, PAGE_SIZE, DMA_BIDIRECTIONAL);
if (dma_mapping_error(dev, *dma_addr))
- goto error_free_page;
+ return -EIO;
- svmm = spage->zone_device_data;
- mutex_lock(&svmm->mutex);
- nouveau_svmm_invalidate(svmm, args->start, args->end);
if (drm->dmem->migrate.copy_func(drm, 1, NOUVEAU_APER_HOST, *dma_addr,
- NOUVEAU_APER_VRAM, nouveau_dmem_page_addr(spage)))
- goto error_dma_unmap;
- mutex_unlock(&svmm->mutex);
+ NOUVEAU_APER_VRAM, nouveau_dmem_page_addr(spage))) {
+ dma_unmap_page(dev, *dma_addr, PAGE_SIZE, DMA_BIDIRECTIONAL);
+ return -EIO;
+ }
- args->dst[0] = migrate_pfn(page_to_pfn(dpage));
return 0;
-
-error_dma_unmap:
- mutex_unlock(&svmm->mutex);
- dma_unmap_page(dev, *dma_addr, PAGE_SIZE, DMA_BIDIRECTIONAL);
-error_free_page:
- __free_page(dpage);
- return VM_FAULT_SIGBUS;
}
static vm_fault_t nouveau_dmem_migrate_to_ram(struct vm_fault *vmf)
@@ -184,9 +164,11 @@ static vm_fault_t nouveau_dmem_migrate_t
struct nouveau_drm *drm = page_to_drm(vmf->page);
struct nouveau_dmem *dmem = drm->dmem;
struct nouveau_fence *fence;
+ struct nouveau_svmm *svmm;
+ struct page *spage, *dpage;
unsigned long src = 0, dst = 0;
dma_addr_t dma_addr = 0;
- vm_fault_t ret;
+ vm_fault_t ret = 0;
struct migrate_vma args = {
.vma = vmf->vma,
.start = vmf->address,
@@ -207,9 +189,25 @@ static vm_fault_t nouveau_dmem_migrate_t
if (!args.cpages)
return 0;
- ret = nouveau_dmem_fault_copy_one(drm, vmf, &args, &dma_addr);
- if (ret || dst == 0)
+ spage = migrate_pfn_to_page(src);
+ if (!spage || !(src & MIGRATE_PFN_MIGRATE))
+ goto done;
+
+ dpage = alloc_page_vma(GFP_HIGHUSER, vmf->vma, vmf->address);
+ if (!dpage)
+ goto done;
+
+ dst = migrate_pfn(page_to_pfn(dpage));
+
+ svmm = spage->zone_device_data;
+ mutex_lock(&svmm->mutex);
+ nouveau_svmm_invalidate(svmm, args.start, args.end);
+ ret = nouveau_dmem_copy_one(drm, spage, dpage, &dma_addr);
+ mutex_unlock(&svmm->mutex);
+ if (ret) {
+ ret = VM_FAULT_SIGBUS;
goto done;
+ }
nouveau_fence_new(dmem->migrate.chan, false, &fence);
migrate_vma_pages(&args);
_
Patches currently in -mm which might be from apopple@xxxxxxxxxx are
mm-memoryc-fix-race-when-faulting-a-device-private-page.patch
mm-free-device-private-pages-have-zero-refcount.patch
mm-memremapc-take-a-pgmap-reference-on-page-allocation.patch
mm-migrate_devicec-refactor-migrate_vma-and-migrate_deivce_coherent_page.patch
mm-migrate_devicec-add-migrate_device_range.patch
nouveau-dmem-refactor-nouveau_dmem_fault_copy_one.patch
nouveau-dmem-evict-device-private-memory-during-release.patch
hmm-tests-add-test-for-migrate_device_range.patch
