[PATCH v3 20/24] powerpc/mm: Allow platforms to redefine some helpers

Christophe Leroy
2018-10-09T13:52:25Z

The 40xx defines _PAGE_HWWRITE while others don't.
The 8xx defines _PAGE_RO instead of _PAGE_RW.
The 8xx defines _PAGE_PRIVILEGED instead of _PAGE_USER.
The 8xx defines _PAGE_HUGE and _PAGE_NA while others don't.

Lets those platforms redefine pte_write(), pte_wrprotect() and
pte_mkwrite() and get _PAGE_RO and _PAGE_HWWRITE off the common
helpers.

Lets the 8xx redefine pte_user(), pte_mkprivileged() and pte_mkuser()
and get rid of _PAGE_PRIVILEGED and _PAGE_USER default values.

Lets the 8xx redefine pte_mkhuge() and get rid of
_PAGE_HUGE default value.

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
arch/powerpc/include/asm/nohash/32/pgtable.h | 16 ++++-----
arch/powerpc/include/asm/nohash/32/pte-40x.h | 16 +++++++++
arch/powerpc/include/asm/nohash/32/pte-8xx.h | 51 ++++++++++++++++++++++++++++
arch/powerpc/include/asm/nohash/64/pgtable.h | 4 ---
arch/powerpc/include/asm/nohash/pgtable.h | 24 +++++++++----
arch/powerpc/include/asm/pte-common.h | 24 -------------
6 files changed, 91 insertions(+), 44 deletions(-)

diff --git a/arch/powerpc/include/asm/nohash/32/pgtable.h b/arch/powerpc/include/asm/nohash/32/pgtable.h
index a4156da4a7a4..ce9270a0ea42 100644
--- a/arch/powerpc/include/asm/nohash/32/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/32/pgtable.h
@@ -136,14 +136,12 @@ extern int icache_44x_need_flush;
#define pte_clear(mm, addr, ptep) \
do { pte_update(ptep, ~0, 0); } while (0)

+#ifndef pte_mkwrite
static inline pte_t pte_mkwrite(pte_t pte)
{
- pte_basic_t ptev;
-
- ptev = pte_val(pte) & ~_PAGE_RO;
- ptev |= _PAGE_RW;
- return __pte(ptev);
+ return __pte(pte_val(pte) | _PAGE_RW);
}
+#endif

static inline pte_t pte_mkdirty(pte_t pte)
{
@@ -155,14 +153,12 @@ static inline pte_t pte_mkyoung(pte_t pte)
return __pte(pte_val(pte) | _PAGE_ACCESSED);
}

+#ifndef pte_wrprotect
static inline pte_t pte_wrprotect(pte_t pte)
{
- pte_basic_t ptev;
-
- ptev = pte_val(pte) & ~(_PAGE_RW | _PAGE_HWWRITE);
- ptev |= _PAGE_RO;
- return __pte(ptev);
+ return __pte(pte_val(pte) & ~_PAGE_RW);
}
+#endif

static inline pte_t pte_mkexec(pte_t pte)
{
diff --git a/arch/powerpc/include/asm/nohash/32/pte-40x.h b/arch/powerpc/include/asm/nohash/32/pte-40x.h
index 2b48bc289a4d..ab043b3e9b99 100644
--- a/arch/powerpc/include/asm/nohash/32/pte-40x.h
+++ b/arch/powerpc/include/asm/nohash/32/pte-40x.h
@@ -87,5 +87,21 @@
#define PAGE_READONLY __pgprot(_PAGE_BASE | _PAGE_USER)
#define PAGE_READONLY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC)

+#ifndef __ASSEMBLY__
+static inline pte_t pte_wrprotect(pte_t pte)
+{
+ return __pte(pte_val(pte) & ~(_PAGE_RW | _PAGE_HWWRITE));
+}
+
+#define pte_wrprotect pte_wrprotect
+
+static inline pte_t pte_mkclean(pte_t pte)
+{
+ return __pte(pte_val(pte) & ~(_PAGE_DIRTY | _PAGE_HWWRITE));
+}
+
+#define pte_mkclean pte_mkclean
+#endif
+
#endif /* __KERNEL__ */
#endif /* _ASM_POWERPC_NOHASH_32_PTE_40x_H */
diff --git a/arch/powerpc/include/asm/nohash/32/pte-8xx.h b/arch/powerpc/include/asm/nohash/32/pte-8xx.h
index d06fc45bd9ac..b899c3c877ac 100644
--- a/arch/powerpc/include/asm/nohash/32/pte-8xx.h
+++ b/arch/powerpc/include/asm/nohash/32/pte-8xx.h
@@ -87,5 +87,56 @@
#define PAGE_READONLY __pgprot(_PAGE_BASE | _PAGE_RO)
#define PAGE_READONLY_X __pgprot(_PAGE_BASE | _PAGE_RO | _PAGE_EXEC)

+#ifndef __ASSEMBLY__
+static inline pte_t pte_wrprotect(pte_t pte)
+{
+ return __pte(pte_val(pte) | _PAGE_RO);
+}
+
+#define pte_wrprotect pte_wrprotect
+
+static inline int pte_write(pte_t pte)
+{
+ return !(pte_val(pte) & _PAGE_RO);
+}
+
+#define pte_write pte_write
+
+static inline pte_t pte_mkwrite(pte_t pte)
+{
+ return __pte(pte_val(pte) & ~_PAGE_RO);
+}
+
+#define pte_mkwrite pte_mkwrite
+
+static inline bool pte_user(pte_t pte)
+{
+ return !(pte_val(pte) & _PAGE_PRIVILEGED);
+}
+
+#define pte_user pte_user
+
+static inline pte_t pte_mkprivileged(pte_t pte)
+{
+ return __pte(pte_val(pte) | _PAGE_PRIVILEGED);
+}
+
+#define pte_mkprivileged pte_mkprivileged
+
+static inline pte_t pte_mkuser(pte_t pte)
+{
+ return __pte(pte_val(pte) & ~_PAGE_PRIVILEGED);
+}
+
+#define pte_mkuser pte_mkuser
+
+static inline pte_t pte_mkhuge(pte_t pte)
+{
+ return __pte(pte_val(pte) | _PAGE_HUGE);
+}
+
+#define pte_mkhuge pte_mkhuge
+#endif
+
#endif /* __KERNEL__ */
#endif /* _ASM_POWERPC_NOHASH_32_PTE_8xx_H */
diff --git a/arch/powerpc/include/asm/nohash/64/pgtable.h b/arch/powerpc/include/asm/nohash/64/pgtable.h
index 9ccea94b3d4e..f272e4599803 100644
--- a/arch/powerpc/include/asm/nohash/64/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/64/pgtable.h
@@ -90,11 +90,7 @@
*/
#include <asm/nohash/pte-book3e.h>

-#define _PAGE_HWWRITE 0
#define _PAGE_SAO 0
-#define _PAGE_RO 0
-#define _PAGE_NA 0
-#define _PAGE_HUGE 0

#define PTE_RPN_MASK (~((1UL << PTE_RPN_SHIFT) - 1))

diff --git a/arch/powerpc/include/asm/nohash/pgtable.h b/arch/powerpc/include/asm/nohash/pgtable.h
index d3feeac19467..d7bc904bd231 100644
--- a/arch/powerpc/include/asm/nohash/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/pgtable.h
@@ -38,10 +38,12 @@
#ifndef __ASSEMBLY__

/* Generic accessors to PTE bits */
+#ifndef pte_write
static inline int pte_write(pte_t pte)
{
- return (pte_val(pte) & (_PAGE_RW | _PAGE_RO)) != _PAGE_RO;
+ return pte_val(pte) & _PAGE_RW;
}
+#endif
static inline int pte_read(pte_t pte) { return 1; }
static inline int pte_dirty(pte_t pte) { return pte_val(pte) & _PAGE_DIRTY; }
static inline int pte_special(pte_t pte) { return pte_val(pte) & _PAGE_SPECIAL; }
@@ -83,10 +85,12 @@ static inline bool pte_hw_valid(pte_t pte)
* and PTE_64BIT, PAGE_KERNEL_X contains _PAGE_BAP_SR which is also in
* _PAGE_USER. Need to explicitly match _PAGE_BAP_UR bit in that case too.
*/
+#ifndef pte_user
static inline bool pte_user(pte_t pte)
{
- return (pte_val(pte) & (_PAGE_USER | _PAGE_PRIVILEGED)) == _PAGE_USER;
+ return (pte_val(pte) & _PAGE_USER) == _PAGE_USER;
}
+#endif

/*
* We only find page table entry in the last level
@@ -126,10 +130,12 @@ static inline pte_t pte_exprotect(pte_t pte)
return __pte(pte_val(pte) & ~_PAGE_EXEC);
}

+#ifndef pte_mkclean
static inline pte_t pte_mkclean(pte_t pte)
{
- return __pte(pte_val(pte) & ~(_PAGE_DIRTY | _PAGE_HWWRITE));
+ return __pte(pte_val(pte) & ~_PAGE_DIRTY);
}
+#endif

static inline pte_t pte_mkold(pte_t pte)
{
@@ -146,20 +152,26 @@ static inline pte_t pte_mkspecial(pte_t pte)
return __pte(pte_val(pte) | _PAGE_SPECIAL);
}

+#ifndef pte_mkhuge
static inline pte_t pte_mkhuge(pte_t pte)
{
- return __pte(pte_val(pte) | _PAGE_HUGE);
+ return __pte(pte_val(pte));
}
+#endif

+#ifndef pte_mkprivileged
static inline pte_t pte_mkprivileged(pte_t pte)
{
- return __pte((pte_val(pte) & ~_PAGE_USER) | _PAGE_PRIVILEGED);
+ return __pte(pte_val(pte) & ~_PAGE_USER);
}
+#endif

+#ifndef pte_mkuser
static inline pte_t pte_mkuser(pte_t pte)
{
- return __pte((pte_val(pte) & ~_PAGE_PRIVILEGED) | _PAGE_USER);
+ return __pte(pte_val(pte) | _PAGE_USER);
}
+#endif

static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
{
diff --git a/arch/powerpc/include/asm/pte-common.h b/arch/powerpc/include/asm/pte-common.h
index 4d594039bca5..1a2102f8b1e7 100644
--- a/arch/powerpc/include/asm/pte-common.h
+++ b/arch/powerpc/include/asm/pte-common.h
@@ -5,36 +5,12 @@
* Some bits are only used on some cpu families... Make sure that all
* the undefined gets a sensible default
*/
-#ifndef _PAGE_HWWRITE
-#define _PAGE_HWWRITE 0
-#endif
#ifndef _PAGE_COHERENT
#define _PAGE_COHERENT 0
#endif
#ifndef _PAGE_WRITETHRU
#define _PAGE_WRITETHRU 0
#endif
-/* _PAGE_RO and _PAGE_RW shall not be defined at the same time */
-#ifndef _PAGE_RO
-#define _PAGE_RO 0
-#else
-#define _PAGE_RW 0
-#endif
-
-/* At least one of _PAGE_PRIVILEGED or _PAGE_USER must be defined */
-#ifndef _PAGE_PRIVILEGED
-#define _PAGE_PRIVILEGED 0
-#else
-#ifndef _PAGE_USER
-#define _PAGE_USER 0
-#endif
-#endif
-#ifndef _PAGE_NA
-#define _PAGE_NA 0
-#endif
-#ifndef _PAGE_HUGE
-#define _PAGE_HUGE 0
-#endif

/* Location of the PFN in the PTE. Most 32-bit platforms use the same
* as _PAGE_SHIFT here (ie, naturally aligned).
--
2.13.3