diff mbox series

[RFC,1/3] mm: add function folio_in_range()

Message ID 20230707165221.4076590-2-fengwei.yin@intel.com
State New
Headers
Series support large folio for mlock |

Commit Message

Yin Fengwei July 7, 2023, 4:52 p.m. UTC 
  It will be used to check whether the folio is mapped to specific
VMA and whether the mapping address of folio is in the range.

Signed-off-by: Yin Fengwei <fengwei.yin@intel.com>
---
 mm/internal.h | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

Comments

Yu Zhao July 8, 2023, 5:47 a.m. UTC | #1 
On Fri, Jul 7, 2023 at 10:52 AM Yin Fengwei <fengwei.yin@intel.com> wrote:
>
> It will be used to check whether the folio is mapped to specific
> VMA and whether the mapping address of folio is in the range.
>
> Signed-off-by: Yin Fengwei <fengwei.yin@intel.com>
> ---
>  mm/internal.h | 26 ++++++++++++++++++++++++++
>  1 file changed, 26 insertions(+)
>
> diff --git a/mm/internal.h b/mm/internal.h
> index f1276d90484ad..66117523d7d71 100644
> --- a/mm/internal.h
> +++ b/mm/internal.h
> @@ -585,6 +585,32 @@ extern long faultin_vma_page_range(struct vm_area_struct *vma,
>                                    bool write, int *locked);
>  extern bool mlock_future_ok(struct mm_struct *mm, unsigned long flags,
>                                unsigned long bytes);
> +
> +static inline bool
> +folio_in_range(struct folio *folio, struct vm_area_struct *vma,
> +               unsigned long start, unsigned long end)

Is there a caller that's not "folio_in_range(folio, vma,
vma->vm_start, vma->vm_end)"?

If not, then just "folio_within_vma(folio, vma)" or a wrapper on top
of  folio_in_range().
Yin Fengwei July 8, 2023, 6:44 a.m. UTC | #2 
On 7/8/2023 1:47 PM, Yu Zhao wrote:
> On Fri, Jul 7, 2023 at 10:52 AM Yin Fengwei <fengwei.yin@intel.com> wrote:
>>
>> It will be used to check whether the folio is mapped to specific
>> VMA and whether the mapping address of folio is in the range.
>>
>> Signed-off-by: Yin Fengwei <fengwei.yin@intel.com>
>> ---
>>  mm/internal.h | 26 ++++++++++++++++++++++++++
>>  1 file changed, 26 insertions(+)
>>
>> diff --git a/mm/internal.h b/mm/internal.h
>> index f1276d90484ad..66117523d7d71 100644
>> --- a/mm/internal.h
>> +++ b/mm/internal.h
>> @@ -585,6 +585,32 @@ extern long faultin_vma_page_range(struct vm_area_struct *vma,
>>                                    bool write, int *locked);
>>  extern bool mlock_future_ok(struct mm_struct *mm, unsigned long flags,
>>                                unsigned long bytes);
>> +
>> +static inline bool
>> +folio_in_range(struct folio *folio, struct vm_area_struct *vma,
>> +               unsigned long start, unsigned long end)
> 
> Is there a caller that's not "folio_in_range(folio, vma,
> vma->vm_start, vma->vm_end)"?
I believe madvise() will use start/end from user space instead of vma start/end.

> 
> If not, then just "folio_within_vma(folio, vma)" or a wrapper on top
> of  folio_in_range().
Will add folio_within_vma() based on folio_in_range(). Thanks.

Regards
Yin, Fengwei
diff mbox series

Patch

diff --git a/mm/internal.h b/mm/internal.h
index f1276d90484ad..66117523d7d71 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -585,6 +585,32 @@  extern long faultin_vma_page_range(struct vm_area_struct *vma,
 				   bool write, int *locked);
 extern bool mlock_future_ok(struct mm_struct *mm, unsigned long flags,
 			       unsigned long bytes);
+
+static inline bool
+folio_in_range(struct folio *folio, struct vm_area_struct *vma,
+		unsigned long start, unsigned long end)
+{
+	pgoff_t pgoff, addr;
+	unsigned long vma_pglen = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
+
+	VM_WARN_ON_FOLIO(folio_test_ksm(folio), folio);
+	if (start < vma->vm_start)
+		start = vma->vm_start;
+
+	if (end > vma->vm_end)
+		end = vma->vm_end;
+
+	pgoff = folio_pgoff(folio);
+
+	/* if folio start address is not in vma range */
+	if (pgoff < vma->vm_pgoff || pgoff > vma->vm_pgoff + vma_pglen)
+		return false;
+
+	addr = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
+
+	return ((addr >= start) && (addr + folio_size(folio) <= end));
+}
+
 /*
  * mlock_vma_folio() and munlock_vma_folio():
  * should be called with vma's mmap_lock held for read or write,