powerpc/mm: Cleanup handling of execute permission
This is an attempt at cleaning up a bit the way we handle execute
permission on powerpc. _PAGE_HWEXEC is gone, _PAGE_EXEC is now only
defined by CPUs that can do something with it, and the myriad of
#ifdef's in the I$/D$ coherency code is reduced to 2 cases that
hopefully should cover everything.
The logic on BookE is a little bit different than what it was though
not by much. Since now, _PAGE_EXEC will be set by the generic code
for executable pages, we need to filter out if they are unclean and
recover it. However, I don't expect the code to be more bloated than
it already was in that area due to that change.
I could boast that this brings proper enforcing of per-page execute
permissions to all BookE and 40x but in fact, we've had that now for
some time as a side effect of my previous rework in that area (and
I didn't even know it :-) We would only enable execute permission if
the page was cache clean and we would only cache clean it if we took
and exec fault. Since we now enforce that the later only work if
VM_EXEC is part of the VMA flags, we de-fact already enforce per-page
execute permissions... Unless I missed something
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/include/asm/pgtable-ppc32.h b/arch/powerpc/include/asm/pgtable-ppc32.h
index c9ff9d7..f2c52e2 100644
--- a/arch/powerpc/include/asm/pgtable-ppc32.h
+++ b/arch/powerpc/include/asm/pgtable-ppc32.h
@@ -186,7 +186,7 @@
#endif /* !PTE_ATOMIC_UPDATES */
#ifdef CONFIG_44x
- if ((old & _PAGE_USER) && (old & _PAGE_HWEXEC))
+ if ((old & _PAGE_USER) && (old & _PAGE_EXEC))
icache_44x_need_flush = 1;
#endif
return old;
@@ -217,7 +217,7 @@
#endif /* !PTE_ATOMIC_UPDATES */
#ifdef CONFIG_44x
- if ((old & _PAGE_USER) && (old & _PAGE_HWEXEC))
+ if ((old & _PAGE_USER) && (old & _PAGE_EXEC))
icache_44x_need_flush = 1;
#endif
return old;
@@ -267,8 +267,7 @@
static inline void __ptep_set_access_flags(pte_t *ptep, pte_t entry)
{
unsigned long bits = pte_val(entry) &
- (_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW |
- _PAGE_HWEXEC | _PAGE_EXEC);
+ (_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW | _PAGE_EXEC);
pte_update(ptep, 0, bits);
}
diff --git a/arch/powerpc/include/asm/pgtable-ppc64.h b/arch/powerpc/include/asm/pgtable-ppc64.h
index 200ec2df..806abe7 100644
--- a/arch/powerpc/include/asm/pgtable-ppc64.h
+++ b/arch/powerpc/include/asm/pgtable-ppc64.h
@@ -313,8 +313,7 @@
static inline void __ptep_set_access_flags(pte_t *ptep, pte_t entry)
{
unsigned long bits = pte_val(entry) &
- (_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW |
- _PAGE_EXEC | _PAGE_HWEXEC);
+ (_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW | _PAGE_EXEC);
#ifdef PTE_ATOMIC_UPDATES
unsigned long old, tmp;
diff --git a/arch/powerpc/include/asm/pte-40x.h b/arch/powerpc/include/asm/pte-40x.h
index 07630fa..6c3e1f4 100644
--- a/arch/powerpc/include/asm/pte-40x.h
+++ b/arch/powerpc/include/asm/pte-40x.h
@@ -46,7 +46,7 @@
#define _PAGE_RW 0x040 /* software: Writes permitted */
#define _PAGE_DIRTY 0x080 /* software: dirty page */
#define _PAGE_HWWRITE 0x100 /* hardware: Dirty & RW, set in exception */
-#define _PAGE_HWEXEC 0x200 /* hardware: EX permission */
+#define _PAGE_EXEC 0x200 /* hardware: EX permission */
#define _PAGE_ACCESSED 0x400 /* software: R: page referenced */
#define _PMD_PRESENT 0x400 /* PMD points to page of PTEs */
diff --git a/arch/powerpc/include/asm/pte-44x.h b/arch/powerpc/include/asm/pte-44x.h
index 37e98bc..4192b9b 100644
--- a/arch/powerpc/include/asm/pte-44x.h
+++ b/arch/powerpc/include/asm/pte-44x.h
@@ -78,7 +78,7 @@
#define _PAGE_PRESENT 0x00000001 /* S: PTE valid */
#define _PAGE_RW 0x00000002 /* S: Write permission */
#define _PAGE_FILE 0x00000004 /* S: nonlinear file mapping */
-#define _PAGE_HWEXEC 0x00000004 /* H: Execute permission */
+#define _PAGE_EXEC 0x00000004 /* H: Execute permission */
#define _PAGE_ACCESSED 0x00000008 /* S: Page referenced */
#define _PAGE_DIRTY 0x00000010 /* S: Page dirty */
#define _PAGE_SPECIAL 0x00000020 /* S: Special page */
diff --git a/arch/powerpc/include/asm/pte-8xx.h b/arch/powerpc/include/asm/pte-8xx.h
index 8c6e312..94e9797 100644
--- a/arch/powerpc/include/asm/pte-8xx.h
+++ b/arch/powerpc/include/asm/pte-8xx.h
@@ -36,7 +36,6 @@
/* These five software bits must be masked out when the entry is loaded
* into the TLB.
*/
-#define _PAGE_EXEC 0x0008 /* software: i-cache coherency required */
#define _PAGE_GUARDED 0x0010 /* software: guarded access */
#define _PAGE_DIRTY 0x0020 /* software: page changed */
#define _PAGE_RW 0x0040 /* software: user write access allowed */
diff --git a/arch/powerpc/include/asm/pte-book3e.h b/arch/powerpc/include/asm/pte-book3e.h
index 1d27c77..9800565 100644
--- a/arch/powerpc/include/asm/pte-book3e.h
+++ b/arch/powerpc/include/asm/pte-book3e.h
@@ -37,12 +37,13 @@
#define _PAGE_WRITETHRU 0x800000 /* W: cache write-through */
/* "Higher level" linux bit combinations */
-#define _PAGE_EXEC _PAGE_BAP_SX /* Can be executed from potentially */
-#define _PAGE_HWEXEC _PAGE_BAP_UX /* .. and was cache cleaned */
-#define _PAGE_RW (_PAGE_BAP_SW | _PAGE_BAP_UW) /* User write permission */
-#define _PAGE_KERNEL_RW (_PAGE_BAP_SW | _PAGE_BAP_SR | _PAGE_DIRTY)
-#define _PAGE_KERNEL_RO (_PAGE_BAP_SR)
-#define _PAGE_USER (_PAGE_BAP_UR | _PAGE_BAP_SR) /* Can be read */
+#define _PAGE_EXEC _PAGE_BAP_UX /* .. and was cache cleaned */
+#define _PAGE_RW (_PAGE_BAP_SW | _PAGE_BAP_UW) /* User write permission */
+#define _PAGE_KERNEL_RW (_PAGE_BAP_SW | _PAGE_BAP_SR | _PAGE_DIRTY)
+#define _PAGE_KERNEL_RO (_PAGE_BAP_SR)
+#define _PAGE_KERNEL_RWX (_PAGE_BAP_SW | _PAGE_BAP_SR | _PAGE_DIRTY | _PAGE_BAP_SX)
+#define _PAGE_KERNEL_ROX (_PAGE_BAP_SR | _PAGE_BAP_SX)
+#define _PAGE_USER (_PAGE_BAP_UR | _PAGE_BAP_SR) /* Can be read */
#define _PAGE_HASHPTE 0
#define _PAGE_BUSY 0
diff --git a/arch/powerpc/include/asm/pte-common.h b/arch/powerpc/include/asm/pte-common.h
index 8bb6464..c3b6507 100644
--- a/arch/powerpc/include/asm/pte-common.h
+++ b/arch/powerpc/include/asm/pte-common.h
@@ -13,9 +13,6 @@
#ifndef _PAGE_HWWRITE
#define _PAGE_HWWRITE 0
#endif
-#ifndef _PAGE_HWEXEC
-#define _PAGE_HWEXEC 0
-#endif
#ifndef _PAGE_EXEC
#define _PAGE_EXEC 0
#endif
@@ -48,10 +45,16 @@
#define PMD_PAGE_SIZE(pmd) bad_call_to_PMD_PAGE_SIZE()
#endif
#ifndef _PAGE_KERNEL_RO
-#define _PAGE_KERNEL_RO 0
+#define _PAGE_KERNEL_RO 0
+#endif
+#ifndef _PAGE_KERNEL_ROX
+#define _PAGE_KERNEL_ROX (_PAGE_EXEC)
#endif
#ifndef _PAGE_KERNEL_RW
-#define _PAGE_KERNEL_RW (_PAGE_DIRTY | _PAGE_RW | _PAGE_HWWRITE)
+#define _PAGE_KERNEL_RW (_PAGE_DIRTY | _PAGE_RW | _PAGE_HWWRITE)
+#endif
+#ifndef _PAGE_KERNEL_RWX
+#define _PAGE_KERNEL_RWX (_PAGE_DIRTY | _PAGE_RW | _PAGE_HWWRITE | _PAGE_EXEC)
#endif
#ifndef _PAGE_HPTEFLAGS
#define _PAGE_HPTEFLAGS _PAGE_HASHPTE
@@ -96,8 +99,7 @@
#define PAGE_PROT_BITS (_PAGE_GUARDED | _PAGE_COHERENT | _PAGE_NO_CACHE | \
_PAGE_WRITETHRU | _PAGE_ENDIAN | _PAGE_4K_PFN | \
_PAGE_USER | _PAGE_ACCESSED | \
- _PAGE_RW | _PAGE_HWWRITE | _PAGE_DIRTY | \
- _PAGE_EXEC | _PAGE_HWEXEC)
+ _PAGE_RW | _PAGE_HWWRITE | _PAGE_DIRTY | _PAGE_EXEC)
/*
* We define 2 sets of base prot bits, one for basic pages (ie,
@@ -154,11 +156,9 @@
_PAGE_NO_CACHE)
#define PAGE_KERNEL_NCG __pgprot(_PAGE_BASE_NC | _PAGE_KERNEL_RW | \
_PAGE_NO_CACHE | _PAGE_GUARDED)
-#define PAGE_KERNEL_X __pgprot(_PAGE_BASE | _PAGE_KERNEL_RW | _PAGE_EXEC | \
- _PAGE_HWEXEC)
+#define PAGE_KERNEL_X __pgprot(_PAGE_BASE | _PAGE_KERNEL_RWX)
#define PAGE_KERNEL_RO __pgprot(_PAGE_BASE | _PAGE_KERNEL_RO)
-#define PAGE_KERNEL_ROX __pgprot(_PAGE_BASE | _PAGE_KERNEL_RO | _PAGE_EXEC | \
- _PAGE_HWEXEC)
+#define PAGE_KERNEL_ROX __pgprot(_PAGE_BASE | _PAGE_KERNEL_ROX)
/* Protection used for kernel text. We want the debuggers to be able to
* set breakpoints anywhere, so don't write protect the kernel text
diff --git a/arch/powerpc/include/asm/pte-fsl-booke.h b/arch/powerpc/include/asm/pte-fsl-booke.h
index 10820f5..ce8a9e9 100644
--- a/arch/powerpc/include/asm/pte-fsl-booke.h
+++ b/arch/powerpc/include/asm/pte-fsl-booke.h
@@ -23,7 +23,7 @@
#define _PAGE_FILE 0x00002 /* S: when !present: nonlinear file mapping */
#define _PAGE_RW 0x00004 /* S: Write permission (SW) */
#define _PAGE_DIRTY 0x00008 /* S: Page dirty */
-#define _PAGE_HWEXEC 0x00010 /* H: SX permission */
+#define _PAGE_EXEC 0x00010 /* H: SX permission */
#define _PAGE_ACCESSED 0x00020 /* S: Page referenced */
#define _PAGE_ENDIAN 0x00040 /* H: E bit */
diff --git a/arch/powerpc/include/asm/pte-hash32.h b/arch/powerpc/include/asm/pte-hash32.h
index 16e571c..4aad413 100644
--- a/arch/powerpc/include/asm/pte-hash32.h
+++ b/arch/powerpc/include/asm/pte-hash32.h
@@ -26,7 +26,6 @@
#define _PAGE_WRITETHRU 0x040 /* W: cache write-through */
#define _PAGE_DIRTY 0x080 /* C: page changed */
#define _PAGE_ACCESSED 0x100 /* R: page referenced */
-#define _PAGE_EXEC 0x200 /* software: i-cache coherency required */
#define _PAGE_RW 0x400 /* software: user write access allowed */
#define _PAGE_SPECIAL 0x800 /* software: Special page */