diff options
Diffstat (limited to 'include/linux/pgtable.h')
| -rw-r--r-- | include/linux/pgtable.h | 28 |
1 files changed, 22 insertions, 6 deletions
diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h index 787c632ee2c9..e2b705c14945 100644 --- a/include/linux/pgtable.h +++ b/include/linux/pgtable.h @@ -1510,15 +1510,26 @@ static inline void track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot, } /* - * track_pfn_copy is called when vma that is covering the pfnmap gets - * copied through copy_page_range(). + * track_pfn_copy is called when a VM_PFNMAP VMA is about to get the page + * tables copied during copy_page_range(). On success, stores the pfn to be + * passed to untrack_pfn_copy(). */ -static inline int track_pfn_copy(struct vm_area_struct *vma) +static inline int track_pfn_copy(struct vm_area_struct *dst_vma, + struct vm_area_struct *src_vma, unsigned long *pfn) { return 0; } /* + * untrack_pfn_copy is called when a VM_PFNMAP VMA failed to copy during + * copy_page_range(), but after track_pfn_copy() was already called. + */ +static inline void untrack_pfn_copy(struct vm_area_struct *dst_vma, + unsigned long pfn) +{ +} + +/* * untrack_pfn is called while unmapping a pfnmap for a region. * untrack can be called for a specific region indicated by pfn and size or * can be for the entire vma (in which case pfn, size are zero). @@ -1530,8 +1541,10 @@ static inline void untrack_pfn(struct vm_area_struct *vma, } /* - * untrack_pfn_clear is called while mremapping a pfnmap for a new region - * or fails to copy pgtable during duplicate vm area. + * untrack_pfn_clear is called in the following cases on a VM_PFNMAP VMA: + * + * 1) During mremap() on the src VMA after the page tables were moved. + * 2) During fork() on the dst VMA, immediately after duplicating the src VMA. */ static inline void untrack_pfn_clear(struct vm_area_struct *vma) { @@ -1542,7 +1555,10 @@ extern int track_pfn_remap(struct vm_area_struct *vma, pgprot_t *prot, unsigned long size); extern void track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot, pfn_t pfn); -extern int track_pfn_copy(struct vm_area_struct *vma); +extern int track_pfn_copy(struct vm_area_struct *dst_vma, + struct vm_area_struct *src_vma, unsigned long *pfn); +extern void untrack_pfn_copy(struct vm_area_struct *dst_vma, + unsigned long pfn); extern void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn, unsigned long size, bool mm_wr_locked); extern void untrack_pfn_clear(struct vm_area_struct *vma); |