diff options
| -rw-r--r-- | mm/memory.c | 27 |
1 files changed, 22 insertions, 5 deletions
diff --git a/mm/memory.c b/mm/memory.c index 3c01d68065be..ebfc9768f801 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -2632,11 +2632,7 @@ static inline int remap_p4d_range(struct mm_struct *mm, pgd_t *pgd, return 0; } -/* - * Variant of remap_pfn_range that does not call track_pfn_remap. The caller - * must have pre-validated the caching bits of the pgprot_t. - */ -int remap_pfn_range_notrack(struct vm_area_struct *vma, unsigned long addr, +static int remap_pfn_range_internal(struct vm_area_struct *vma, unsigned long addr, unsigned long pfn, unsigned long size, pgprot_t prot) { pgd_t *pgd; @@ -2689,6 +2685,27 @@ int remap_pfn_range_notrack(struct vm_area_struct *vma, unsigned long addr, return 0; } +/* + * Variant of remap_pfn_range that does not call track_pfn_remap. The caller + * must have pre-validated the caching bits of the pgprot_t. + */ +int remap_pfn_range_notrack(struct vm_area_struct *vma, unsigned long addr, + unsigned long pfn, unsigned long size, pgprot_t prot) +{ + int error = remap_pfn_range_internal(vma, addr, pfn, size, prot); + + if (!error) + return 0; + + /* + * A partial pfn range mapping is dangerous: it does not + * maintain page reference counts, and callers may free + * pages due to the error. So zap it early. + */ + zap_page_range_single(vma, addr, size, NULL); + return error; +} + /** * remap_pfn_range - remap kernel memory to userspace * @vma: user vma to map to |