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author | Dave Kleikamp <shaggy@linux.vnet.ibm.com> | 2008-07-07 16:28:51 +0200 |
---|---|---|
committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2008-07-09 08:30:45 +0200 |
commit | b845f313d78e4e259ec449909e3bbadf77b53a6d (patch) | |
tree | 03239e77dbc43f627ce112963736c8b4c53117e6 /mm | |
parent | powerpc: Implement task_pt_regs() accessor (diff) | |
download | linux-b845f313d78e4e259ec449909e3bbadf77b53a6d.tar.xz linux-b845f313d78e4e259ec449909e3bbadf77b53a6d.zip |
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 <shaggy@linux.vnet.ibm.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'mm')
-rw-r--r-- | mm/mmap.c | 5 | ||||
-rw-r--r-- | mm/mprotect.c | 2 |
2 files changed, 4 insertions, 3 deletions
diff --git a/mm/mmap.c b/mm/mmap.c index 3354fdd83d4b..1d102b956fd8 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 a5bf31c27375..ecfaa5844b5f 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; |