From: Jérôme Glisse <jgli...@redhat.com>
All device driver we care about are using 64bits page table entry. In
order to match this and to avoid useless define convert all HMM pfn to
directly use uint64_t. It is a first step on the road to allow driver
to directly use pfn value return by HMM (saving memory and CPU cycles
use for convertion between the two).
Signed-off-by: Jérôme Glisse <jgli...@redhat.com>
Cc: Evgeny Baskakov <ebaska...@nvidia.com>
Cc: Ralph Campbell <rcampb...@nvidia.com>
Cc: Mark Hairgrove <mhairgr...@nvidia.com>
Cc: John Hubbard <jhubb...@nvidia.com>
---
include/linux/hmm.h | 46 +++++++++++++++++++++-------------------------
mm/hmm.c | 26 +++++++++++++-------------
2 files changed, 34 insertions(+), 38 deletions(-)
diff --git a/include/linux/hmm.h b/include/linux/hmm.h
index 4bdc58ffe9f3..78b3ed6d7977 100644
--- a/include/linux/hmm.h
+++ b/include/linux/hmm.h
@@ -80,8 +80,6 @@
struct hmm;
/*
- * hmm_pfn_t - HMM uses its own pfn type to keep several flags per page
- *
* Flags:
* HMM_PFN_VALID: pfn is valid
* HMM_PFN_WRITE: CPU page table has write permission set
@@ -93,8 +91,6 @@ struct hmm;
* set and the pfn value is undefined.
* HMM_PFN_DEVICE_UNADDRESSABLE: unaddressable device memory (ZONE_DEVICE)
*/
-typedef unsigned long hmm_pfn_t;
-
#define HMM_PFN_VALID (1 << 0)
#define HMM_PFN_WRITE (1 << 1)
#define HMM_PFN_ERROR (1 << 2)
@@ -104,14 +100,14 @@ typedef unsigned long hmm_pfn_t;
#define HMM_PFN_SHIFT 6
/*
- * hmm_pfn_t_to_page() - return struct page pointed to by a valid hmm_pfn_t
- * @pfn: hmm_pfn_t to convert to struct page
- * Returns: struct page pointer if pfn is a valid hmm_pfn_t, NULL otherwise
+ * hmm_pfn_to_page() - return struct page pointed to by a valid HMM pfn
+ * @pfn: HMM pfn value to get corresponding struct page from
+ * Returns: struct page pointer if pfn is a valid HMM pfn, NULL otherwise
*
- * If the hmm_pfn_t is valid (ie valid flag set) then return the struct page
- * matching the pfn value stored in the hmm_pfn_t. Otherwise return NULL.
+ * If the uint64_t is valid (ie valid flag set) then return the struct page
+ * matching the pfn value stored in the HMM pfn. Otherwise return NULL.
*/
-static inline struct page *hmm_pfn_t_to_page(hmm_pfn_t pfn)
+static inline struct page *hmm_pfn_to_page(uint64_t pfn)
{
if (!(pfn & HMM_PFN_VALID))
return NULL;
@@ -119,11 +115,11 @@ static inline struct page *hmm_pfn_t_to_page(hmm_pfn_t
pfn)
}
/*
- * hmm_pfn_t_to_pfn() - return pfn value store in a hmm_pfn_t
- * @pfn: hmm_pfn_t to extract pfn from
- * Returns: pfn value if hmm_pfn_t is valid, -1UL otherwise
+ * hmm_pfn_to_pfn() - return pfn value store in a HMM pfn
+ * @pfn: HMM pfn value to extract pfn from
+ * Returns: pfn value if HMM pfn is valid, -1UL otherwise
*/
-static inline unsigned long hmm_pfn_t_to_pfn(hmm_pfn_t pfn)
+static inline unsigned long hmm_pfn_to_pfn(uint64_t pfn)
{
if (!(pfn & HMM_PFN_VALID))
return -1UL;
@@ -131,21 +127,21 @@ static inline unsigned long hmm_pfn_t_to_pfn(hmm_pfn_t
pfn)
}
/*
- * hmm_pfn_t_from_page() - create a valid hmm_pfn_t value from struct page
- * @page: struct page pointer for which to create the hmm_pfn_t
- * Returns: valid hmm_pfn_t for the page
+ * hmm_pfn_from_page() - create a valid HMM pfn value from struct page
+ * @page: struct page pointer for which to create the HMM pfn
+ * Returns: valid HMM pfn for the page
*/
-static inline hmm_pfn_t hmm_pfn_t_from_page(struct page *page)
+static inline uint64_t hmm_pfn_from_page(struct page *page)
{
return (page_to_pfn(page) << HMM_PFN_SHIFT) | HMM_PFN_VALID;
}
/*
- * hmm_pfn_t_from_pfn() - create a valid hmm_pfn_t value from pfn
- * @pfn: pfn value for which to create the hmm_pfn_t
- * Returns: valid hmm_pfn_t for the pfn
+ * hmm_pfn_from_pfn() - create a valid HMM pfn value from pfn
+ * @pfn: pfn value for which to create the HMM pfn
+ * Returns: valid HMM pfn for the pfn
*/
-static inline hmm_pfn_t hmm_pfn_t_from_pfn(unsigned long pfn)
+static inline uint64_t hmm_pfn_from_pfn(unsigned long pfn)
{
return (pfn << HMM_PFN_SHIFT) | HMM_PFN_VALID;
}
@@ -284,7 +280,7 @@ struct hmm_range {
struct list_head list;
unsigned long start;
unsigned long end;
- hmm_pfn_t *pfns;
+ uint64_t *pfns;
bool valid;
};
@@ -307,7 +303,7 @@ bool hmm_vma_range_done(struct hmm_range *range);
/*
* Fault memory on behalf of device driver. Unlike handle_mm_fault(), this will
- * not migrate any device memory back to system memory. The hmm_pfn_t array
will
+ * not migrate any device memory back to system memory. The HMM pfn array will
* be updated with the fault result and current snapshot of the CPU page table
* for the range.
*
@@ -316,7 +312,7 @@ bool hmm_vma_range_done(struct hmm_range *range);
* function returns -EAGAIN.
*
* Return value does not reflect if the fault was successful for every single
- * address or not. Therefore, the caller must to inspect the hmm_pfn_t array to
+ * address or not. Therefore, the caller must to inspect the HMM pfn array to
* determine fault status for each address.
*
* Trying to fault inside an invalid vma will result in -EINVAL.
diff --git a/mm/hmm.c b/mm/hmm.c
index fa3c605c4b96..f674b73e7f4a 100644
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -261,7 +261,7 @@ struct hmm_vma_walk {
static int hmm_vma_do_fault(struct mm_walk *walk,
unsigned long addr,
- hmm_pfn_t *pfn)
+ uint64_t *pfn)
{
unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_REMOTE;
struct hmm_vma_walk *hmm_vma_walk = walk->private;
@@ -281,7 +281,7 @@ static int hmm_vma_do_fault(struct mm_walk *walk,
return -EAGAIN;
}
-static void hmm_pfns_special(hmm_pfn_t *pfns,
+static void hmm_pfns_special(uint64_t *pfns,
unsigned long addr,
unsigned long end)
{
@@ -295,7 +295,7 @@ static int hmm_pfns_bad(unsigned long addr,
{
struct hmm_vma_walk *hmm_vma_walk = walk->private;
struct hmm_range *range = hmm_vma_walk->range;
- hmm_pfn_t *pfns = range->pfns;
+ uint64_t *pfns = range->pfns;
unsigned long i;
i = (addr - range->start) >> PAGE_SHIFT;
@@ -305,7 +305,7 @@ static int hmm_pfns_bad(unsigned long addr,
return 0;
}
-static void hmm_pfns_clear(hmm_pfn_t *pfns,
+static void hmm_pfns_clear(uint64_t *pfns,
unsigned long addr,
unsigned long end)
{
@@ -319,7 +319,7 @@ static int hmm_vma_walk_hole(unsigned long addr,
{
struct hmm_vma_walk *hmm_vma_walk = walk->private;
struct hmm_range *range = hmm_vma_walk->range;
- hmm_pfn_t *pfns = range->pfns;
+ uint64_t *pfns = range->pfns;
unsigned long i;
hmm_vma_walk->last = addr;
@@ -344,7 +344,7 @@ static int hmm_vma_walk_clear(unsigned long addr,
{
struct hmm_vma_walk *hmm_vma_walk = walk->private;
struct hmm_range *range = hmm_vma_walk->range;
- hmm_pfn_t *pfns = range->pfns;
+ uint64_t *pfns = range->pfns;
unsigned long i;
hmm_vma_walk->last = addr;
@@ -371,7 +371,7 @@ static int hmm_vma_walk_pmd(pmd_t *pmdp,
struct hmm_vma_walk *hmm_vma_walk = walk->private;
struct hmm_range *range = hmm_vma_walk->range;
struct vm_area_struct *vma = walk->vma;
- hmm_pfn_t *pfns = range->pfns;
+ uint64_t *pfns = range->pfns;
unsigned long addr = start, i;
bool write_fault;
pte_t *ptep;
@@ -388,7 +388,7 @@ static int hmm_vma_walk_pmd(pmd_t *pmdp,
if (pmd_devmap(*pmdp) || pmd_trans_huge(*pmdp)) {
unsigned long pfn;
- hmm_pfn_t flag = 0;
+ uint64_t flag = 0;
pmd_t pmd;
/*
@@ -413,7 +413,7 @@ static int hmm_vma_walk_pmd(pmd_t *pmdp,
pfn = pmd_pfn(pmd) + pte_index(addr);
flag |= pmd_write(pmd) ? HMM_PFN_WRITE : 0;
for (; addr < end; addr += PAGE_SIZE, i++, pfn++)
- pfns[i] = hmm_pfn_t_from_pfn(pfn) | flag;
+ pfns[i] = hmm_pfn_from_pfn(pfn) | flag;
return 0;
}
@@ -447,7 +447,7 @@ static int hmm_vma_walk_pmd(pmd_t *pmdp,
* device and report anything else as error.
*/
if (is_device_private_entry(entry)) {
- pfns[i] = hmm_pfn_t_from_pfn(swp_offset(entry));
+ pfns[i] = hmm_pfn_from_pfn(swp_offset(entry));
if (is_write_device_private_entry(entry)) {
pfns[i] |= HMM_PFN_WRITE;
} else if (write_fault)
@@ -472,7 +472,7 @@ static int hmm_vma_walk_pmd(pmd_t *pmdp,
if (write_fault && !pte_write(pte))
goto fault;
- pfns[i] = hmm_pfn_t_from_pfn(pte_pfn(pte));
+ pfns[i] = hmm_pfn_from_pfn(pte_pfn(pte));
pfns[i] |= pte_write(pte) ? HMM_PFN_WRITE : 0;
continue;
@@ -634,8 +634,8 @@ EXPORT_SYMBOL(hmm_vma_range_done);
* This is similar to a regular CPU page fault except that it will not trigger
* any memory migration if the memory being faulted is not accessible by CPUs.
*
- * On error, for one virtual address in the range, the function will set the
- * hmm_pfn_t error flag for the corresponding pfn entry.
+ * On error, for one virtual address in the range, the function will mark the
+ * correspond HMM pfn entry with error flag.
*
* Expected use pattern:
* retry:
--
2.14.3
