diff options
| -rw-r--r-- | include/linux/mm.h | 2 | ||||
| -rw-r--r-- | include/linux/mm_types.h | 7 | ||||
| -rw-r--r-- | mm/memory.c | 57 |
3 files changed, 19 insertions, 47 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index c3abad7e6ccb..55d02356146c 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3179,8 +3179,6 @@ vm_fault_t vmf_insert_pfn_prot(struct vm_area_struct *vma, unsigned long addr, unsigned long pfn, pgprot_t pgprot); vm_fault_t vmf_insert_mixed(struct vm_area_struct *vma, unsigned long addr, pfn_t pfn); -vm_fault_t vmf_insert_mixed_prot(struct vm_area_struct *vma, unsigned long addr, - pfn_t pfn, pgprot_t pgprot); vm_fault_t vmf_insert_mixed_mkwrite(struct vm_area_struct *vma, unsigned long addr, pfn_t pfn); int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long len); diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 0722859c3647..651a5c256732 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -485,12 +485,7 @@ struct vm_area_struct { within vm_mm. */ struct mm_struct *vm_mm; /* The address space we belong to. */ - - /* - * Access permissions of this VMA. - * See vmf_insert_mixed_prot() for discussion. - */ - pgprot_t vm_page_prot; + pgprot_t vm_page_prot; /* Access permissions of this VMA. */ /* * Flags, see mm.h. diff --git a/mm/memory.c b/mm/memory.c index 0ee13d3de88c..7716f2cc4b68 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -2165,8 +2165,20 @@ out_unlock: * vmf_insert_pfn_prot should only be used if using multiple VMAs is * impractical. * - * See vmf_insert_mixed_prot() for a discussion of the implication of using - * a value of @pgprot different from that of @vma->vm_page_prot. + * pgprot typically only differs from @vma->vm_page_prot when drivers set + * caching- and encryption bits different than those of @vma->vm_page_prot, + * because the caching- or encryption mode may not be known at mmap() time. + * + * This is ok as long as @vma->vm_page_prot is not used by the core vm + * to set caching and encryption bits for those vmas (except for COW pages). + * This is ensured by core vm only modifying these page table entries using + * functions that don't touch caching- or encryption bits, using pte_modify() + * if needed. (See for example mprotect()). + * + * Also when new page-table entries are created, this is only done using the + * fault() callback, and never using the value of vma->vm_page_prot, + * except for page-table entries that point to anonymous pages as the result + * of COW. * * Context: Process context. May allocate using %GFP_KERNEL. * Return: vm_fault_t value. @@ -2241,9 +2253,9 @@ static bool vm_mixed_ok(struct vm_area_struct *vma, pfn_t pfn) } static vm_fault_t __vm_insert_mixed(struct vm_area_struct *vma, - unsigned long addr, pfn_t pfn, pgprot_t pgprot, - bool mkwrite) + unsigned long addr, pfn_t pfn, bool mkwrite) { + pgprot_t pgprot = vma->vm_page_prot; int err; BUG_ON(!vm_mixed_ok(vma, pfn)); @@ -2286,43 +2298,10 @@ static vm_fault_t __vm_insert_mixed(struct vm_area_struct *vma, return VM_FAULT_NOPAGE; } -/** - * vmf_insert_mixed_prot - insert single pfn into user vma with specified pgprot - * @vma: user vma to map to - * @addr: target user address of this page - * @pfn: source kernel pfn - * @pgprot: pgprot flags for the inserted page - * - * This is exactly like vmf_insert_mixed(), except that it allows drivers - * to override pgprot on a per-page basis. - * - * Typically this function should be used by drivers to set caching- and - * encryption bits different than those of @vma->vm_page_prot, because - * the caching- or encryption mode may not be known at mmap() time. - * This is ok as long as @vma->vm_page_prot is not used by the core vm - * to set caching and encryption bits for those vmas (except for COW pages). - * This is ensured by core vm only modifying these page table entries using - * functions that don't touch caching- or encryption bits, using pte_modify() - * if needed. (See for example mprotect()). - * Also when new page-table entries are created, this is only done using the - * fault() callback, and never using the value of vma->vm_page_prot, - * except for page-table entries that point to anonymous pages as the result - * of COW. - * - * Context: Process context. May allocate using %GFP_KERNEL. - * Return: vm_fault_t value. - */ -vm_fault_t vmf_insert_mixed_prot(struct vm_area_struct *vma, unsigned long addr, - pfn_t pfn, pgprot_t pgprot) -{ - return __vm_insert_mixed(vma, addr, pfn, pgprot, false); -} -EXPORT_SYMBOL(vmf_insert_mixed_prot); - vm_fault_t vmf_insert_mixed(struct vm_area_struct *vma, unsigned long addr, pfn_t pfn) { - return __vm_insert_mixed(vma, addr, pfn, vma->vm_page_prot, false); + return __vm_insert_mixed(vma, addr, pfn, false); } EXPORT_SYMBOL(vmf_insert_mixed); @@ -2334,7 +2313,7 @@ EXPORT_SYMBOL(vmf_insert_mixed); vm_fault_t vmf_insert_mixed_mkwrite(struct vm_area_struct *vma, unsigned long addr, pfn_t pfn) { - return __vm_insert_mixed(vma, addr, pfn, vma->vm_page_prot, true); + return __vm_insert_mixed(vma, addr, pfn, true); } EXPORT_SYMBOL(vmf_insert_mixed_mkwrite); |