Remove the code to fault device private pages back into system memory
that has never been used by any driver. Also replace the usage of the
HMM_PFN_DEVICE_PRIVATE flag in the pfns array with a simple
is_device_private_page check in nouveau.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 1 -
drivers/gpu/drm/nouveau/nouveau_dmem.c | 5 +++--
drivers/gpu/drm/nouveau/nouveau_svm.c | 1 -
include/linux/hmm.h | 2 --
mm/hmm.c | 25 +++++--------------------
5 files changed, 8 insertions(+), 26 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
index dee446278417..90821ce5e6ca 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
@@ -776,7 +776,6 @@ struct amdgpu_ttm_tt {
static const uint64_t hmm_range_flags[HMM_PFN_FLAG_MAX] = {
(1 << 0), /* HMM_PFN_VALID */
(1 << 1), /* HMM_PFN_WRITE */
- 0 /* HMM_PFN_DEVICE_PRIVATE */
};
static const uint64_t hmm_range_values[HMM_PFN_VALUE_MAX] = {
diff --git a/drivers/gpu/drm/nouveau/nouveau_dmem.c b/drivers/gpu/drm/nouveau/nouveau_dmem.c
index 0e36345d395c..edfd0805fba4 100644
--- a/drivers/gpu/drm/nouveau/nouveau_dmem.c
+++ b/drivers/gpu/drm/nouveau/nouveau_dmem.c
@@ -28,6 +28,7 @@
#include <nvif/class.h>
#include <nvif/object.h>
+#include <nvif/if000c.h>
#include <nvif/if500b.h>
#include <nvif/if900b.h>
@@ -692,9 +693,8 @@ nouveau_dmem_convert_pfn(struct nouveau_drm *drm,
if (page == NULL)
continue;
- if (!(range->pfns[i] & range->flags[HMM_PFN_DEVICE_PRIVATE])) {
+ if (!is_device_private_page(page))
continue;
- }
if (!nouveau_dmem_page(drm, page)) {
WARN(1, "Some unknown device memory !\n");
@@ -705,5 +705,6 @@ nouveau_dmem_convert_pfn(struct nouveau_drm *drm,
addr = nouveau_dmem_page_addr(page);
range->pfns[i] &= ((1UL << range->pfn_shift) - 1);
range->pfns[i] |= (addr >> PAGE_SHIFT) << range->pfn_shift;
+ range->pfns[i] |= NVIF_VMM_PFNMAP_V0_VRAM;
}
}
diff --git a/drivers/gpu/drm/nouveau/nouveau_svm.c b/drivers/gpu/drm/nouveau/nouveau_svm.c
index df9bf1fd1bc0..39c731a99937 100644
--- a/drivers/gpu/drm/nouveau/nouveau_svm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_svm.c
@@ -367,7 +367,6 @@ static const u64
nouveau_svm_pfn_flags[HMM_PFN_FLAG_MAX] = {
[HMM_PFN_VALID ] = NVIF_VMM_PFNMAP_V0_V,
[HMM_PFN_WRITE ] = NVIF_VMM_PFNMAP_V0_W,
- [HMM_PFN_DEVICE_PRIVATE] = NVIF_VMM_PFNMAP_V0_VRAM,
};
static const u64
diff --git a/include/linux/hmm.h b/include/linux/hmm.h
index 4bf8d6997b12..5e6034f105c3 100644
--- a/include/linux/hmm.h
+++ b/include/linux/hmm.h
@@ -74,7 +74,6 @@
* Flags:
* HMM_PFN_VALID: pfn is valid. It has, at least, read permission.
* HMM_PFN_WRITE: CPU page table has write permission set
- * HMM_PFN_DEVICE_PRIVATE: private device memory (ZONE_DEVICE)
*
* The driver provides a flags array for mapping page protections to device
* PTE bits. If the driver valid bit for an entry is bit 3,
@@ -86,7 +85,6 @@
enum hmm_pfn_flag_e {
HMM_PFN_VALID = 0,
HMM_PFN_WRITE,
- HMM_PFN_DEVICE_PRIVATE,
HMM_PFN_FLAG_MAX
};
diff --git a/mm/hmm.c b/mm/hmm.c
index 180e398170b0..cfad65f6a67b 100644
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -118,15 +118,6 @@ static inline void hmm_pte_need_fault(const struct hmm_vma_walk *hmm_vma_walk,
/* We aren't ask to do anything ... */
if (!(pfns & range->flags[HMM_PFN_VALID]))
return;
- /* If this is device memory then only fault if explicitly requested */
- if ((cpu_flags & range->flags[HMM_PFN_DEVICE_PRIVATE])) {
- /* Do we fault on device memory ? */
- if (pfns & range->flags[HMM_PFN_DEVICE_PRIVATE]) {
- *write_fault = pfns & range->flags[HMM_PFN_WRITE];
- *fault = true;
- }
- return;
- }
/* If CPU page table is not valid then we need to fault */
*fault = !(cpu_flags & range->flags[HMM_PFN_VALID]);
@@ -260,21 +251,15 @@ static int hmm_vma_handle_pte(struct mm_walk *walk, unsigned long addr,
swp_entry_t entry = pte_to_swp_entry(pte);
/*
- * This is a special swap entry, ignore migration, use
- * device and report anything else as error.
+ * Never fault in device private pages pages, but just report
+ * the PFN even if not present.
*/
if (is_device_private_entry(entry)) {
- cpu_flags = range->flags[HMM_PFN_VALID] |
- range->flags[HMM_PFN_DEVICE_PRIVATE];
- cpu_flags |= is_write_device_private_entry(entry) ?
- range->flags[HMM_PFN_WRITE] : 0;
- hmm_pte_need_fault(hmm_vma_walk, orig_pfn, cpu_flags,
- &fault, &write_fault);
- if (fault || write_fault)
- goto fault;
*pfn = hmm_device_entry_from_pfn(range,
swp_offset(entry));
- *pfn |= cpu_flags;
+ *pfn |= range->flags[HMM_PFN_VALID];
+ if (is_write_device_private_entry(entry))
+ *pfn |= range->flags[HMM_PFN_WRITE];
return 0;
}
--
2.24.1
