[PATCH V2 05/68] powerpc/mm: use _PAGE_READ to indicate Read access
Aneesh Kumar K.V
aneesh.kumar at linux.vnet.ibm.com
Sat Apr 9 16:13:01 AEST 2016
This split _PAGE_RW bit to _PAGE_READ and _PAGE_WRITE. It also remove
the dependency on _PAGE_USER for implying read only. Few things to note
here is that, we have read implied with write and execute permission.
Hence we should always find _PAGE_READ set on hash pte fault.
We still can't switch PROT_NONE to !(_PAGE_RWX). Auto numa do depend
on marking a prot none pte _PAGE_WRITE. (For more details look at
b191f9b106ea "mm: numa: preserve PTE write permissions across a NUMA hinting fault")
Cc: Arnd Bergmann <arnd at arndb.de>
Cc: Jeremy Kerr <jk at ozlabs.org>
Cc: Frederic Barrat <fbarrat at linux.vnet.ibm.com>
Acked-by: Ian Munsie <imunsie at au1.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar at linux.vnet.ibm.com>
---
arch/powerpc/include/asm/book3s/64/hash-64k.h | 4 +--
arch/powerpc/include/asm/book3s/64/hash.h | 35 ++++++++++++++++-----------
arch/powerpc/include/asm/pte-common.h | 5 ++++
arch/powerpc/mm/hash64_4k.c | 2 +-
arch/powerpc/mm/hash64_64k.c | 4 +--
arch/powerpc/mm/hash_utils_64.c | 9 ++++---
arch/powerpc/mm/hugepage-hash64.c | 2 +-
arch/powerpc/mm/hugetlbpage-hash64.c | 2 +-
arch/powerpc/mm/hugetlbpage.c | 4 +--
arch/powerpc/mm/pgtable.c | 4 +--
arch/powerpc/mm/pgtable_64.c | 5 ++--
arch/powerpc/platforms/cell/spu_base.c | 2 +-
arch/powerpc/platforms/cell/spufs/fault.c | 4 +--
drivers/misc/cxl/fault.c | 4 +--
14 files changed, 49 insertions(+), 37 deletions(-)
diff --git a/arch/powerpc/include/asm/book3s/64/hash-64k.h b/arch/powerpc/include/asm/book3s/64/hash-64k.h
index 0a7956a80a08..279ded72f1db 100644
--- a/arch/powerpc/include/asm/book3s/64/hash-64k.h
+++ b/arch/powerpc/include/asm/book3s/64/hash-64k.h
@@ -291,10 +291,10 @@ static inline void pmdp_set_wrprotect(struct mm_struct *mm, unsigned long addr,
pmd_t *pmdp)
{
- if ((pmd_val(*pmdp) & _PAGE_RW) == 0)
+ if ((pmd_val(*pmdp) & _PAGE_WRITE) == 0)
return;
- pmd_hugepage_update(mm, addr, pmdp, _PAGE_RW, 0);
+ pmd_hugepage_update(mm, addr, pmdp, _PAGE_WRITE, 0);
}
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
diff --git a/arch/powerpc/include/asm/book3s/64/hash.h b/arch/powerpc/include/asm/book3s/64/hash.h
index 2113de051824..f092d83fa623 100644
--- a/arch/powerpc/include/asm/book3s/64/hash.h
+++ b/arch/powerpc/include/asm/book3s/64/hash.h
@@ -16,8 +16,10 @@
#define _PAGE_BIT_SWAP_TYPE 0
#define _PAGE_EXEC 0x00001 /* execute permission */
-#define _PAGE_RW 0x00002 /* read & write access allowed */
+#define _PAGE_WRITE 0x00002 /* write access allowed */
#define _PAGE_READ 0x00004 /* read access allowed */
+#define _PAGE_RW (_PAGE_READ | _PAGE_WRITE)
+#define _PAGE_RWX (_PAGE_READ | _PAGE_WRITE | _PAGE_EXEC)
#define _PAGE_USER 0x00008 /* page may be accessed by userspace */
#define _PAGE_GUARDED 0x00010 /* G: guarded (side-effect) page */
/* M (memory coherence) is always set in the HPTE, so we don't need it here */
@@ -147,8 +149,8 @@
*/
#define PAGE_PROT_BITS (_PAGE_GUARDED | _PAGE_COHERENT | _PAGE_NO_CACHE | \
_PAGE_WRITETHRU | _PAGE_4K_PFN | \
- _PAGE_USER | _PAGE_ACCESSED | \
- _PAGE_RW | _PAGE_DIRTY | _PAGE_EXEC | \
+ _PAGE_USER | _PAGE_ACCESSED | _PAGE_READ |\
+ _PAGE_WRITE | _PAGE_DIRTY | _PAGE_EXEC | \
_PAGE_SOFT_DIRTY)
/*
* We define 2 sets of base prot bits, one for basic pages (ie,
@@ -173,10 +175,12 @@
#define PAGE_SHARED __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW)
#define PAGE_SHARED_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW | \
_PAGE_EXEC)
-#define PAGE_COPY __pgprot(_PAGE_BASE | _PAGE_USER )
-#define PAGE_COPY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC)
-#define PAGE_READONLY __pgprot(_PAGE_BASE | _PAGE_USER )
-#define PAGE_READONLY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC)
+#define PAGE_COPY __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_READ)
+#define PAGE_COPY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_READ| \
+ _PAGE_EXEC)
+#define PAGE_READONLY __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_READ)
+#define PAGE_READONLY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_READ| \
+ _PAGE_EXEC)
#define __P000 PAGE_NONE
#define __P001 PAGE_READONLY
@@ -300,19 +304,19 @@ static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr,
pte_t *ptep)
{
- if ((pte_val(*ptep) & _PAGE_RW) == 0)
+ if ((pte_val(*ptep) & _PAGE_WRITE) == 0)
return;
- pte_update(mm, addr, ptep, _PAGE_RW, 0, 0);
+ pte_update(mm, addr, ptep, _PAGE_WRITE, 0, 0);
}
static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
unsigned long addr, pte_t *ptep)
{
- if ((pte_val(*ptep) & _PAGE_RW) == 0)
+ if ((pte_val(*ptep) & _PAGE_WRITE) == 0)
return;
- pte_update(mm, addr, ptep, _PAGE_RW, 0, 1);
+ pte_update(mm, addr, ptep, _PAGE_WRITE, 0, 1);
}
/*
@@ -352,7 +356,7 @@ static inline void pte_clear(struct mm_struct *mm, unsigned long addr,
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_DIRTY | _PAGE_ACCESSED | _PAGE_READ | _PAGE_WRITE | _PAGE_EXEC |
_PAGE_SOFT_DIRTY);
unsigned long old, tmp;
@@ -386,7 +390,7 @@ static inline unsigned long pgd_page_vaddr(pgd_t pgd)
/* Generic accessors to PTE bits */
-static inline int pte_write(pte_t pte) { return !!(pte_val(pte) & _PAGE_RW);}
+static inline int pte_write(pte_t pte) { return !!(pte_val(pte) & _PAGE_WRITE);}
static inline int pte_dirty(pte_t pte) { return !!(pte_val(pte) & _PAGE_DIRTY); }
static inline int pte_young(pte_t pte) { return !!(pte_val(pte) & _PAGE_ACCESSED); }
static inline int pte_special(pte_t pte) { return !!(pte_val(pte) & _PAGE_SPECIAL); }
@@ -447,7 +451,7 @@ static inline unsigned long pte_pfn(pte_t pte)
/* Generic modifiers for PTE bits */
static inline pte_t pte_wrprotect(pte_t pte)
{
- return __pte(pte_val(pte) & ~_PAGE_RW);
+ return __pte(pte_val(pte) & ~_PAGE_WRITE);
}
static inline pte_t pte_mkclean(pte_t pte)
@@ -462,6 +466,9 @@ static inline pte_t pte_mkold(pte_t pte)
static inline pte_t pte_mkwrite(pte_t pte)
{
+ /*
+ * write implies read, hence set both
+ */
return __pte(pte_val(pte) | _PAGE_RW);
}
diff --git a/arch/powerpc/include/asm/pte-common.h b/arch/powerpc/include/asm/pte-common.h
index 1ec67b043065..9f5dea58b0db 100644
--- a/arch/powerpc/include/asm/pte-common.h
+++ b/arch/powerpc/include/asm/pte-common.h
@@ -198,3 +198,8 @@ extern unsigned long bad_call_to_PMD_PAGE_SIZE(void);
/* Advertise support for _PAGE_SPECIAL */
#define __HAVE_ARCH_PTE_SPECIAL
+#ifndef _PAGE_READ
+/* if not defined, we should not find _PAGE_WRITE too */
+#define _PAGE_READ 0
+#define _PAGE_WRITE _PAGE_RW
+#endif
diff --git a/arch/powerpc/mm/hash64_4k.c b/arch/powerpc/mm/hash64_4k.c
index 71abd4c44c27..7ebac279d38e 100644
--- a/arch/powerpc/mm/hash64_4k.c
+++ b/arch/powerpc/mm/hash64_4k.c
@@ -46,7 +46,7 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
* also add _PAGE_COMBO
*/
new_pte = old_pte | _PAGE_BUSY | _PAGE_ACCESSED;
- if (access & _PAGE_RW)
+ if (access & _PAGE_WRITE)
new_pte |= _PAGE_DIRTY;
opte = cpu_to_be64(old_pte);
diff --git a/arch/powerpc/mm/hash64_64k.c b/arch/powerpc/mm/hash64_64k.c
index 6f9b3c34a5c0..83ac9f658733 100644
--- a/arch/powerpc/mm/hash64_64k.c
+++ b/arch/powerpc/mm/hash64_64k.c
@@ -78,7 +78,7 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
* also add _PAGE_COMBO
*/
new_pte = old_pte | _PAGE_BUSY | _PAGE_ACCESSED | _PAGE_COMBO;
- if (access & _PAGE_RW)
+ if (access & _PAGE_WRITE)
new_pte |= _PAGE_DIRTY;
opte = cpu_to_be64(old_pte);
@@ -255,7 +255,7 @@ int __hash_page_64K(unsigned long ea, unsigned long access,
* a write access.
*/
new_pte = old_pte | _PAGE_BUSY | _PAGE_ACCESSED;
- if (access & _PAGE_RW)
+ if (access & _PAGE_WRITE)
new_pte |= _PAGE_DIRTY;
opte = cpu_to_be64(old_pte);
npte = cpu_to_be64(new_pte);
diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index 90dd9280894f..ea23403b3fc0 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -175,8 +175,9 @@ unsigned long htab_convert_pte_flags(unsigned long pteflags)
* or PP=0x3 for read-only (including writeable but clean pages).
*/
if (pteflags & _PAGE_USER) {
- rflags |= 0x2;
- if (!((pteflags & _PAGE_RW) && (pteflags & _PAGE_DIRTY)))
+ if (pteflags & _PAGE_RWX)
+ rflags |= 0x2;
+ if (!((pteflags & _PAGE_WRITE) && (pteflags & _PAGE_DIRTY)))
rflags |= 0x1;
}
/*
@@ -1205,7 +1206,7 @@ EXPORT_SYMBOL_GPL(hash_page);
int __hash_page(unsigned long ea, unsigned long msr, unsigned long trap,
unsigned long dsisr)
{
- unsigned long access = _PAGE_PRESENT;
+ unsigned long access = _PAGE_PRESENT | _PAGE_READ;
unsigned long flags = 0;
struct mm_struct *mm = current->mm;
@@ -1216,7 +1217,7 @@ int __hash_page(unsigned long ea, unsigned long msr, unsigned long trap,
flags |= HPTE_NOHPTE_UPDATE;
if (dsisr & DSISR_ISSTORE)
- access |= _PAGE_RW;
+ access |= _PAGE_WRITE;
/*
* We need to set the _PAGE_USER bit if MSR_PR is set or if we are
* accessing a userspace segment (even from the kernel). We assume
diff --git a/arch/powerpc/mm/hugepage-hash64.c b/arch/powerpc/mm/hugepage-hash64.c
index 98891139c044..39342638a498 100644
--- a/arch/powerpc/mm/hugepage-hash64.c
+++ b/arch/powerpc/mm/hugepage-hash64.c
@@ -48,7 +48,7 @@ int __hash_page_thp(unsigned long ea, unsigned long access, unsigned long vsid,
* a write access
*/
new_pmd = old_pmd | _PAGE_BUSY | _PAGE_ACCESSED;
- if (access & _PAGE_RW)
+ if (access & _PAGE_WRITE)
new_pmd |= _PAGE_DIRTY;
opmd = cpu_to_be64(old_pmd);
npmd = cpu_to_be64(new_pmd);
diff --git a/arch/powerpc/mm/hugetlbpage-hash64.c b/arch/powerpc/mm/hugetlbpage-hash64.c
index 5bcb28606158..e6e54a04bd32 100644
--- a/arch/powerpc/mm/hugetlbpage-hash64.c
+++ b/arch/powerpc/mm/hugetlbpage-hash64.c
@@ -56,7 +56,7 @@ int __hash_page_huge(unsigned long ea, unsigned long access, unsigned long vsid,
/* Try to lock the PTE, add ACCESSED and DIRTY if it was
* a write access */
new_pte = old_pte | _PAGE_BUSY | _PAGE_ACCESSED;
- if (access & _PAGE_RW)
+ if (access & _PAGE_WRITE)
new_pte |= _PAGE_DIRTY;
opte = cpu_to_be64(old_pte);
npte = cpu_to_be64(new_pte);
diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index 6dd272b6196f..6e52e722d3f2 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -1003,9 +1003,9 @@ int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr,
end = pte_end;
pte = READ_ONCE(*ptep);
- mask = _PAGE_PRESENT | _PAGE_USER;
+ mask = _PAGE_PRESENT | _PAGE_USER | _PAGE_READ;
if (write)
- mask |= _PAGE_RW;
+ mask |= _PAGE_WRITE;
if ((pte_val(pte) & mask) != mask)
return 0;
diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c
index 83dfd7925c72..98b5c03e344d 100644
--- a/arch/powerpc/mm/pgtable.c
+++ b/arch/powerpc/mm/pgtable.c
@@ -177,8 +177,8 @@ void set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep,
* _PAGE_PRESENT, but we can be sure that it is not in hpte.
* Hence we can use set_pte_at for them.
*/
- VM_WARN_ON((pte_val(*ptep) & (_PAGE_PRESENT | _PAGE_USER)) ==
- (_PAGE_PRESENT | _PAGE_USER));
+ VM_WARN_ON(pte_present(*ptep) && !pte_protnone(*ptep));
+
/*
* Add the pte bit when tryint set a pte
*/
diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c
index aa742aa35b64..00d8d985bba3 100644
--- a/arch/powerpc/mm/pgtable_64.c
+++ b/arch/powerpc/mm/pgtable_64.c
@@ -277,7 +277,7 @@ void __iomem * ioremap_prot(phys_addr_t addr, unsigned long size,
void *caller = __builtin_return_address(0);
/* writeable implies dirty for kernel addresses */
- if (flags & _PAGE_RW)
+ if (flags & _PAGE_WRITE)
flags |= _PAGE_DIRTY;
/* we don't want to let _PAGE_USER and _PAGE_EXEC leak out */
@@ -681,8 +681,7 @@ void set_pmd_at(struct mm_struct *mm, unsigned long addr,
pmd_t *pmdp, pmd_t pmd)
{
#ifdef CONFIG_DEBUG_VM
- WARN_ON((pmd_val(*pmdp) & (_PAGE_PRESENT | _PAGE_USER)) ==
- (_PAGE_PRESENT | _PAGE_USER));
+ WARN_ON(pte_present(pmd_pte(*pmdp)) && !pte_protnone(pmd_pte(*pmdp)));
assert_spin_locked(&mm->page_table_lock);
WARN_ON(!pmd_trans_huge(pmd));
#endif
diff --git a/arch/powerpc/platforms/cell/spu_base.c b/arch/powerpc/platforms/cell/spu_base.c
index f7af74f83693..7bc00b508128 100644
--- a/arch/powerpc/platforms/cell/spu_base.c
+++ b/arch/powerpc/platforms/cell/spu_base.c
@@ -197,7 +197,7 @@ static int __spu_trap_data_map(struct spu *spu, unsigned long ea, u64 dsisr)
(REGION_ID(ea) != USER_REGION_ID)) {
spin_unlock(&spu->register_lock);
- ret = hash_page(ea, _PAGE_PRESENT, 0x300, dsisr);
+ ret = hash_page(ea, _PAGE_PRESENT | _PAGE_READ, 0x300, dsisr);
spin_lock(&spu->register_lock);
if (!ret) {
diff --git a/arch/powerpc/platforms/cell/spufs/fault.c b/arch/powerpc/platforms/cell/spufs/fault.c
index d98f845ac777..c3a3bf1745b7 100644
--- a/arch/powerpc/platforms/cell/spufs/fault.c
+++ b/arch/powerpc/platforms/cell/spufs/fault.c
@@ -141,8 +141,8 @@ int spufs_handle_class1(struct spu_context *ctx)
/* we must not hold the lock when entering copro_handle_mm_fault */
spu_release(ctx);
- access = (_PAGE_PRESENT | _PAGE_USER);
- access |= (dsisr & MFC_DSISR_ACCESS_PUT) ? _PAGE_RW : 0UL;
+ access = (_PAGE_PRESENT | _PAGE_READ | _PAGE_USER);
+ access |= (dsisr & MFC_DSISR_ACCESS_PUT) ? _PAGE_WRITE : 0UL;
local_irq_save(flags);
ret = hash_page(ea, access, 0x300, dsisr);
local_irq_restore(flags);
diff --git a/drivers/misc/cxl/fault.c b/drivers/misc/cxl/fault.c
index 9a236543da23..0feeacedcef1 100644
--- a/drivers/misc/cxl/fault.c
+++ b/drivers/misc/cxl/fault.c
@@ -149,9 +149,9 @@ static void cxl_handle_page_fault(struct cxl_context *ctx,
* update_mmu_cache() will not have loaded the hash since current->trap
* is not a 0x400 or 0x300, so just call hash_page_mm() here.
*/
- access = _PAGE_PRESENT;
+ access = _PAGE_PRESENT | _PAGE_READ;
if (dsisr & CXL_PSL_DSISR_An_S)
- access |= _PAGE_RW;
+ access |= _PAGE_WRITE;
if ((!ctx->kernel) || (REGION_ID(dar) == USER_REGION_ID))
access |= _PAGE_USER;
--
2.5.0
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