From b1e10575aa4d52c5955aedd828eb84a07f35ca4b Mon Sep 17 00:00:00 2001
From: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Date: Tue, 8 Jul 2008 00:28:51 +1000
Subject: [PATCH] --- yaml --- r: 101771 b: refs/heads/master c:
 b845f313d78e4e259ec449909e3bbadf77b53a6d h: refs/heads/master i:   101769:
 55cf247b064c24c033b5b0dd81e43a09248467f0   101767:
 cd3aae277f7436f4f92a6f3bfb5d1f3983832c69 v: v3

---
 [refs]                     |  2 +-
 trunk/include/linux/mman.h | 29 ++++++++++++++++++++++++++++-
 trunk/mm/mmap.c            |  5 +++--
 trunk/mm/mprotect.c        |  2 +-
 4 files changed, 33 insertions(+), 5 deletions(-)

diff --git a/[refs] b/[refs]
index a658b1ec2e1d..43069ef7c2ed 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: e5093ff05d36c64e8f36a9ddb26358256dc133ea
+refs/heads/master: b845f313d78e4e259ec449909e3bbadf77b53a6d
diff --git a/trunk/include/linux/mman.h b/trunk/include/linux/mman.h
index dab8892e6ff1..30d1073bac3b 100644
--- a/trunk/include/linux/mman.h
+++ b/trunk/include/linux/mman.h
@@ -33,6 +33,32 @@ static inline void vm_unacct_memory(long pages)
 	vm_acct_memory(-pages);
 }
 
+/*
+ * Allow architectures to handle additional protection bits
+ */
+
+#ifndef arch_calc_vm_prot_bits
+#define arch_calc_vm_prot_bits(prot) 0
+#endif
+
+#ifndef arch_vm_get_page_prot
+#define arch_vm_get_page_prot(vm_flags) __pgprot(0)
+#endif
+
+#ifndef arch_validate_prot
+/*
+ * This is called from mprotect().  PROT_GROWSDOWN and PROT_GROWSUP have
+ * already been masked out.
+ *
+ * Returns true if the prot flags are valid
+ */
+static inline int arch_validate_prot(unsigned long prot)
+{
+	return (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM)) == 0;
+}
+#define arch_validate_prot arch_validate_prot
+#endif
+
 /*
  * Optimisation macro.  It is equivalent to:
  *      (x & bit1) ? bit2 : 0
@@ -51,7 +77,8 @@ calc_vm_prot_bits(unsigned long prot)
 {
 	return _calc_vm_trans(prot, PROT_READ,  VM_READ ) |
 	       _calc_vm_trans(prot, PROT_WRITE, VM_WRITE) |
-	       _calc_vm_trans(prot, PROT_EXEC,  VM_EXEC );
+	       _calc_vm_trans(prot, PROT_EXEC,  VM_EXEC) |
+	       arch_calc_vm_prot_bits(prot);
 }
 
 /*
diff --git a/trunk/mm/mmap.c b/trunk/mm/mmap.c
index 3354fdd83d4b..1d102b956fd8 100644
--- a/trunk/mm/mmap.c
+++ b/trunk/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/trunk/mm/mprotect.c b/trunk/mm/mprotect.c
index a5bf31c27375..ecfaa5844b5f 100644
--- a/trunk/mm/mprotect.c
+++ b/trunk/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;