xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

mm/hmm: Use hmm_mirror not mm as an argument for hmm_range_register

Browse Source 
Ralph observes that hmm_range_register() can only be called by a driver
while a mirror is registered. Make this clear in the API by passing in the
mirror structure as a parameter.

This also simplifies understanding the lifetime model for struct hmm, as
the hmm pointer must be valid as part of a registered mirror so all we
need in hmm_register_range() is a simple kref_get.

Suggested-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Philip Yang <Philip.Yang@amd.com>
This commit is contained in:
Jason Gunthorpe
2019-05-23 09:41:19 -03:00
parent 6d7c3cde93
commit e36acfe6c8
3 changed files with 9 additions and 13 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
drivers/gpu/drm/nouveau/nouveau_svm.c
View File

@@ -649,7 +649,7 @@ nouveau_svm_fault(struct nvif_notify *notify)
range.values = nouveau_svm_pfn_values; range.values = nouveau_svm_pfn_values;
range.pfn_shift = NVIF_VMM_PFNMAP_V0_ADDR_SHIFT; range.pfn_shift = NVIF_VMM_PFNMAP_V0_ADDR_SHIFT;
again: again:
ret = hmm_vma_fault(&range, true); ret = hmm_vma_fault(&svmm->mirror, &range, true);
if (ret == 0) { if (ret == 0) {
mutex_lock(&svmm->mutex); mutex_lock(&svmm->mutex);
if (!hmm_vma_range_done(&range)) { if (!hmm_vma_range_done(&range)) {

7
include/linux/hmm.h
View File

@@ -496,7 +496,7 @@ static inline bool hmm_mirror_mm_is_alive(struct hmm_mirror *mirror)
* Please see Documentation/vm/hmm.rst for how to use the range API. * Please see Documentation/vm/hmm.rst for how to use the range API.
*/ */
int hmm_range_register(struct hmm_range *range, int hmm_range_register(struct hmm_range *range,
struct mm_struct *mm, struct hmm_mirror *mirror,
unsigned long start, unsigned long start,
unsigned long end, unsigned long end,
unsigned page_shift); unsigned page_shift);
@@ -532,7 +532,8 @@ static inline bool hmm_vma_range_done(struct hmm_range *range)
} }
/* This is a temporary helper to avoid merge conflict between trees. */ /* This is a temporary helper to avoid merge conflict between trees. */
static inline int hmm_vma_fault(struct hmm_range *range, bool block) static inline int hmm_vma_fault(struct hmm_mirror *mirror,
struct hmm_range *range, bool block)
{ {
long ret; long ret;
@@ -545,7 +546,7 @@ static inline int hmm_vma_fault(struct hmm_range *range, bool block)
range->default_flags = 0; range->default_flags = 0;
range->pfn_flags_mask = -1UL; range->pfn_flags_mask = -1UL;
ret = hmm_range_register(range, range->vma->vm_mm, ret = hmm_range_register(range, mirror,
range->start, range->end, range->start, range->end,
PAGE_SHIFT); PAGE_SHIFT);
if (ret) if (ret)

13
mm/hmm.c
View File

@@ -914,13 +914,13 @@ static void hmm_pfns_clear(struct hmm_range *range,
* Track updates to the CPU page table see include/linux/hmm.h * Track updates to the CPU page table see include/linux/hmm.h
*/ */
int hmm_range_register(struct hmm_range *range, int hmm_range_register(struct hmm_range *range,
struct mm_struct *mm, struct hmm_mirror *mirror,
unsigned long start, unsigned long start,
unsigned long end, unsigned long end,
unsigned page_shift) unsigned page_shift)
{ {
unsigned long mask = ((1UL << page_shift) - 1UL); unsigned long mask = ((1UL << page_shift) - 1UL);
struct hmm *hmm; struct hmm *hmm = mirror->hmm;
range->valid = false; range->valid = false;
range->hmm = NULL; range->hmm = NULL;
@@ -934,20 +934,15 @@ int hmm_range_register(struct hmm_range *range,
range->start = start; range->start = start;
range->end = end; range->end = end;
hmm = hmm_get_or_create(mm);
if (!hmm)
return -EFAULT;
/* Check if hmm_mm_destroy() was call. */ /* Check if hmm_mm_destroy() was call. */
if (hmm->mm == NULL || hmm->dead) { if (hmm->mm == NULL || hmm->dead)
hmm_put(hmm);
return -EFAULT; return -EFAULT;
}
/* Initialize range to track CPU page table updates. */ /* Initialize range to track CPU page table updates. */
mutex_lock(&hmm->lock); mutex_lock(&hmm->lock);
range->hmm = hmm; range->hmm = hmm;
kref_get(&hmm->kref);
list_add_rcu(&range->list, &hmm->ranges); list_add_rcu(&range->list, &hmm->ranges);
/* /*