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| author | Dan Williams | 2016-01-16 01:56:55 +0100 |
|---|---|---|
| committer | Linus Torvalds | 2016-01-16 02:56:32 +0100 |
| commit | 3565fce3a6597e91b8dee3e8e36ebf70f8b7ef9b (patch) | |
| tree | 54f05861c87cb2c2710552b61a46cb5831b06296 /include/linux/huge_mm.h | |
| parent | mm, dax: dax-pmd vs thp-pmd vs hugetlbfs-pmd (diff) | |
| download | kernel-qcow2-linux-3565fce3a6597e91b8dee3e8e36ebf70f8b7ef9b.tar.gz kernel-qcow2-linux-3565fce3a6597e91b8dee3e8e36ebf70f8b7ef9b.tar.xz kernel-qcow2-linux-3565fce3a6597e91b8dee3e8e36ebf70f8b7ef9b.zip | |
mm, x86: get_user_pages() for dax mappings
A dax mapping establishes a pte with _PAGE_DEVMAP set when the driver
has established a devm_memremap_pages() mapping, i.e. when the pfn_t
return from ->direct_access() has PFN_DEV and PFN_MAP set. Later, when
encountering _PAGE_DEVMAP during a page table walk we lookup and pin a
struct dev_pagemap instance to keep the result of pfn_to_page() valid
until put_page().
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Logan Gunthorpe <logang@deltatee.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux/huge_mm.h')
| -rw-r--r-- | include/linux/huge_mm.h | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h index d39fa60bd6bf..cfe81e10bd54 100644 --- a/include/linux/huge_mm.h +++ b/include/linux/huge_mm.h @@ -38,7 +38,6 @@ extern int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, int prot_numa); int vmf_insert_pfn_pmd(struct vm_area_struct *, unsigned long addr, pmd_t *, pfn_t pfn, bool write); - enum transparent_hugepage_flag { TRANSPARENT_HUGEPAGE_FLAG, TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG, @@ -55,6 +54,9 @@ enum transparent_hugepage_flag { #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER) #ifdef CONFIG_TRANSPARENT_HUGEPAGE +struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr, + pmd_t *pmd, int flags); + #define HPAGE_PMD_SHIFT PMD_SHIFT #define HPAGE_PMD_SIZE ((1UL) << HPAGE_PMD_SHIFT) #define HPAGE_PMD_MASK (~(HPAGE_PMD_SIZE - 1)) @@ -205,6 +207,12 @@ static inline bool is_huge_zero_page(struct page *page) return false; } + +static inline struct page *follow_devmap_pmd(struct vm_area_struct *vma, + unsigned long addr, pmd_t *pmd, int flags) +{ + return NULL; +} #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ #endif /* _LINUX_HUGE_MM_H */ |