From b845f313d78e4e259ec449909e3bbadf77b53a6d Mon Sep 17 00:00:00 2001 From: Dave Kleikamp Date: Tue, 8 Jul 2008 00:28:51 +1000 Subject: mm: Allow architectures to define additional protection bits This patch allows architectures to define functions to deal with additional protections bits for mmap() and mprotect(). arch_calc_vm_prot_bits() maps additonal protection bits to vm_flags arch_vm_get_page_prot() maps additional vm_flags to the vma's vm_page_prot arch_validate_prot() checks for valid values of the protection bits Note: vm_get_page_prot() is now pretty ugly, but the generated code should be identical for architectures that don't define additional protection bits. Signed-off-by: Dave Kleikamp Acked-by: Andrew Morton Acked-by: Hugh Dickins Signed-off-by: Benjamin Herrenschmidt --- mm/mmap.c | 5 +++-- mm/mprotect.c | 2 +- 2 files changed, 4 insertions(+), 3 deletions(-) (limited to 'mm') diff --git a/mm/mmap.c b/mm/mmap.c index 3354fdd83d4..1d102b956fd 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -72,8 +72,9 @@ pgprot_t protection_map[16] = { pgprot_t vm_get_page_prot(unsigned long vm_flags) { - return protection_map[vm_flags & - (VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)]; + return __pgprot(pgprot_val(protection_map[vm_flags & + (VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)]) | + pgprot_val(arch_vm_get_page_prot(vm_flags))); } EXPORT_SYMBOL(vm_get_page_prot); diff --git a/mm/mprotect.c b/mm/mprotect.c index a5bf31c2737..ecfaa5844b5 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -239,7 +239,7 @@ sys_mprotect(unsigned long start, size_t len, unsigned long prot) end = start + len; if (end <= start) return -ENOMEM; - if (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM)) + if (!arch_validate_prot(prot)) return -EINVAL; reqprot = prot; -- cgit v1.2.3