[PATCH 1/6] powerpc/mm: Remove duplicate declaration of setbat()

[PATCH 1/6] powerpc/mm: Remove duplicate declaration of setbat()

[Michael Ellerman]

This is already declared in mmu_decl.h, so we don't need a second
version in the C file.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/mm/pgtable_32.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c
index 03b1a3b0fbd5..72555ab145cd 100644
--- a/arch/powerpc/mm/pgtable_32.c
+++ b/arch/powerpc/mm/pgtable_32.c
@@ -54,9 +54,6 @@ extern char etext[], _stext[];
 #ifdef HAVE_BATS
 extern phys_addr_t v_mapped_by_bats(unsigned long va);
 extern unsigned long p_mapped_by_bats(phys_addr_t pa);
-void setbat(int index, unsigned long virt, phys_addr_t phys,
-	    unsigned int size, int flags);
-
 #else /* !HAVE_BATS */
 #define v_mapped_by_bats(x)	(0UL)
 #define p_mapped_by_bats(x)	(0UL)
-- 
2.1.0

[PATCH 2/6] powerpc/mm: Change setbat() to take a pgprot_t rather than flags

[Michael Ellerman]

The callers of setbat() are actually passing a pgprot_t for the flags
parameter. This doesn't matter unless STRICT_MM_TYPECHECKS is enabled.
So we can turn that on without breaking the build, change setbat() to
take a pgprot_t and have it convert it to an unsigned long internally.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/mm/mmu_decl.h   | 2 +-
 arch/powerpc/mm/ppc_mmu_32.c | 3 ++-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/mm/mmu_decl.h b/arch/powerpc/mm/mmu_decl.h
index 78c45f392f5b..085b66b10891 100644
--- a/arch/powerpc/mm/mmu_decl.h
+++ b/arch/powerpc/mm/mmu_decl.h
@@ -96,7 +96,7 @@ extern void _tlbia(void);
 extern void mapin_ram(void);
 extern int map_page(unsigned long va, phys_addr_t pa, int flags);
 extern void setbat(int index, unsigned long virt, phys_addr_t phys,
-		   unsigned int size, int flags);
+		   unsigned int size, pgprot_t prot);
 
 extern int __map_without_bats;
 extern int __allow_ioremap_reserved;
diff --git a/arch/powerpc/mm/ppc_mmu_32.c b/arch/powerpc/mm/ppc_mmu_32.c
index 5029dc19b517..94f33721d382 100644
--- a/arch/powerpc/mm/ppc_mmu_32.c
+++ b/arch/powerpc/mm/ppc_mmu_32.c
@@ -113,11 +113,12 @@ unsigned long __init mmu_mapin_ram(unsigned long top)
  * of 2 between 128k and 256M.
  */
 void __init setbat(int index, unsigned long virt, phys_addr_t phys,
-		   unsigned int size, int flags)
+		   unsigned int size, pgprot_t prot)
 {
 	unsigned int bl;
 	int wimgxpp;
 	struct ppc_bat *bat = BATS[index];
+	unsigned long flags = pgprot_val(prot);
 
 	if ((flags & _PAGE_NO_CACHE) ||
 	    (cpu_has_feature(CPU_FTR_NEED_COHERENT) == 0))
-- 
2.1.0

[PATCH 3/6] powerpc: Make STRICT_MM_TYPECHECKS a config option

[Michael Ellerman]

The STRICT_MM_TYPECHECKS code has bit-rotted over the years. To make it
possible to easily build test it, make it a CONFIG option.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/Kconfig.debug               | 8 ++++++++
 arch/powerpc/include/asm/page.h          | 4 +---
 arch/powerpc/include/asm/pgtable-ppc64.h | 2 +-
 3 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/Kconfig.debug b/arch/powerpc/Kconfig.debug
index ec2e40f2cc11..777108f4acab 100644
--- a/arch/powerpc/Kconfig.debug
+++ b/arch/powerpc/Kconfig.debug
@@ -19,6 +19,14 @@ config PPC_WERROR
 	depends on !PPC_DISABLE_WERROR
 	default y
 
+config STRICT_MM_TYPECHECKS
+	bool "Do extra type checking on mm types"
+	default n
+	help
+	  This option turns on extra type checking for some mm related types.
+
+	  If you don't know what this means, say N.
+
 config PRINT_STACK_DEPTH
 	int "Stack depth to print" if DEBUG_KERNEL
 	default 64
diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
index 69c059887a2c..71294a6e976e 100644
--- a/arch/powerpc/include/asm/page.h
+++ b/arch/powerpc/include/asm/page.h
@@ -278,9 +278,7 @@ extern long long virt_phys_offset;
 
 #ifndef __ASSEMBLY__
 
-#undef STRICT_MM_TYPECHECKS
-
-#ifdef STRICT_MM_TYPECHECKS
+#ifdef CONFIG_STRICT_MM_TYPECHECKS
 /* These are used to make use of C type-checking. */
 
 /* PTE level */
diff --git a/arch/powerpc/include/asm/pgtable-ppc64.h b/arch/powerpc/include/asm/pgtable-ppc64.h
index 43e6ad424c7f..f951d9cf358a 100644
--- a/arch/powerpc/include/asm/pgtable-ppc64.h
+++ b/arch/powerpc/include/asm/pgtable-ppc64.h
@@ -118,7 +118,7 @@
  */
 #ifndef __real_pte
 
-#ifdef STRICT_MM_TYPECHECKS
+#ifdef CONFIG_STRICT_MM_TYPECHECKS
 #define __real_pte(e,p)		((real_pte_t){(e)})
 #define __rpte_to_pte(r)	((r).pte)
 #else
-- 
2.1.0

[PATCH 4/6] powerpc: Fix compile errors with STRICT_MM_TYPECHECKS enabled

[Michael Ellerman]

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Fix the 32-bit code also]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/include/asm/kvm_book3s_64.h | 12 +++++++-----
 arch/powerpc/mm/dma-noncoherent.c        |  2 +-
 arch/powerpc/mm/fsl_booke_mmu.c          |  2 +-
 arch/powerpc/mm/hugepage-hash64.c        |  2 +-
 arch/powerpc/mm/hugetlbpage.c            |  4 ++--
 arch/powerpc/mm/pgtable_32.c             |  4 ++--
 arch/powerpc/mm/pgtable_64.c             |  2 +-
 arch/powerpc/mm/tlb_hash64.c             |  2 +-
 8 files changed, 16 insertions(+), 14 deletions(-)

diff --git a/arch/powerpc/include/asm/kvm_book3s_64.h b/arch/powerpc/include/asm/kvm_book3s_64.h
index 2d81e202bdcc..cc073a7ac2b7 100644
--- a/arch/powerpc/include/asm/kvm_book3s_64.h
+++ b/arch/powerpc/include/asm/kvm_book3s_64.h
@@ -290,11 +290,11 @@ static inline pte_t kvmppc_read_update_linux_pte(pte_t *ptep, int writing,
 	pte_t old_pte, new_pte = __pte(0);
 
 	while (1) {
-		old_pte = pte_val(*ptep);
+		old_pte = *ptep;
 		/*
 		 * wait until _PAGE_BUSY is clear then set it atomically
 		 */
-		if (unlikely(old_pte & _PAGE_BUSY)) {
+		if (unlikely(pte_val(old_pte) & _PAGE_BUSY)) {
 			cpu_relax();
 			continue;
 		}
@@ -305,16 +305,18 @@ static inline pte_t kvmppc_read_update_linux_pte(pte_t *ptep, int writing,
 			return __pte(0);
 #endif
 		/* If pte is not present return None */
-		if (unlikely(!(old_pte & _PAGE_PRESENT)))
+		if (unlikely(!(pte_val(old_pte) & _PAGE_PRESENT)))
 			return __pte(0);
 
 		new_pte = pte_mkyoung(old_pte);
 		if (writing && pte_write(old_pte))
 			new_pte = pte_mkdirty(new_pte);
 
-		if (old_pte == __cmpxchg_u64((unsigned long *)ptep, old_pte,
-					     new_pte))
+		if (pte_val(old_pte) == __cmpxchg_u64((unsigned long *)ptep,
+						      pte_val(old_pte),
+						      pte_val(new_pte))) {
 			break;
+		}
 	}
 	return new_pte;
 }
diff --git a/arch/powerpc/mm/dma-noncoherent.c b/arch/powerpc/mm/dma-noncoherent.c
index d85e86aac7fb..169aba446a74 100644
--- a/arch/powerpc/mm/dma-noncoherent.c
+++ b/arch/powerpc/mm/dma-noncoherent.c
@@ -228,7 +228,7 @@ __dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *handle, gfp_t
 		do {
 			SetPageReserved(page);
 			map_page(vaddr, page_to_phys(page),
-				 pgprot_noncached(PAGE_KERNEL));
+				 pgprot_val(pgprot_noncached(PAGE_KERNEL)));
 			page++;
 			vaddr += PAGE_SIZE;
 		} while (size -= PAGE_SIZE);
diff --git a/arch/powerpc/mm/fsl_booke_mmu.c b/arch/powerpc/mm/fsl_booke_mmu.c
index b46912fee7cd..9c90e66cffb6 100644
--- a/arch/powerpc/mm/fsl_booke_mmu.c
+++ b/arch/powerpc/mm/fsl_booke_mmu.c
@@ -181,7 +181,7 @@ static unsigned long map_mem_in_cams_addr(phys_addr_t phys, unsigned long virt,
 		unsigned long cam_sz;
 
 		cam_sz = calc_cam_sz(ram, virt, phys);
-		settlbcam(i, virt, phys, cam_sz, PAGE_KERNEL_X, 0);
+		settlbcam(i, virt, phys, cam_sz, pgprot_val(PAGE_KERNEL_X), 0);
 
 		ram -= cam_sz;
 		amount_mapped += cam_sz;
diff --git a/arch/powerpc/mm/hugepage-hash64.c b/arch/powerpc/mm/hugepage-hash64.c
index 86686514ae13..43dafb9d6a46 100644
--- a/arch/powerpc/mm/hugepage-hash64.c
+++ b/arch/powerpc/mm/hugepage-hash64.c
@@ -33,7 +33,7 @@ int __hash_page_thp(unsigned long ea, unsigned long access, unsigned long vsid,
 	 * atomically mark the linux large page PMD busy and dirty
 	 */
 	do {
-		pmd_t pmd = ACCESS_ONCE(*pmdp);
+		pmd_t pmd = READ_ONCE(*pmdp);
 
 		old_pmd = pmd_val(pmd);
 		/* If PMD busy, retry the access */
diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index 7e408bfc7948..fa9d5c238d22 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -964,7 +964,7 @@ pte_t *find_linux_pte_or_hugepte(pgd_t *pgdir, unsigned long ea, unsigned *shift
 		*shift = 0;
 
 	pgdp = pgdir + pgd_index(ea);
-	pgd  = ACCESS_ONCE(*pgdp);
+	pgd  = READ_ONCE(*pgdp);
 	/*
 	 * Always operate on the local stack value. This make sure the
 	 * value don't get updated by a parallel THP split/collapse,
@@ -1045,7 +1045,7 @@ int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr,
 	if (pte_end < end)
 		end = pte_end;
 
-	pte = ACCESS_ONCE(*ptep);
+	pte = READ_ONCE(*ptep);
 	mask = _PAGE_PRESENT | _PAGE_USER;
 	if (write)
 		mask |= _PAGE_RW;
diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c
index 72555ab145cd..ecc503cb78ed 100644
--- a/arch/powerpc/mm/pgtable_32.c
+++ b/arch/powerpc/mm/pgtable_32.c
@@ -189,7 +189,7 @@ __ioremap_caller(phys_addr_t addr, unsigned long size, unsigned long flags,
 
 	/* Make sure we have the base flags */
 	if ((flags & _PAGE_PRESENT) == 0)
-		flags |= PAGE_KERNEL;
+		flags |= pgprot_val(PAGE_KERNEL);
 
 	/* Non-cacheable page cannot be coherent */
 	if (flags & _PAGE_NO_CACHE)
@@ -324,7 +324,7 @@ void __init __mapin_ram_chunk(unsigned long offset, unsigned long top)
 	p = memstart_addr + s;
 	for (; s < top; s += PAGE_SIZE) {
 		ktext = ((char *) v >= _stext && (char *) v < etext);
-		f = ktext ? PAGE_KERNEL_TEXT : PAGE_KERNEL;
+		f = ktext ? pgprot_val(PAGE_KERNEL_TEXT) : pgprot_val(PAGE_KERNEL);
 		map_page(v, p, f);
 #ifdef CONFIG_PPC_STD_MMU_32
 		if (ktext)
diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c
index 6957cc1ca0a7..3ac3a0a1edfb 100644
--- a/arch/powerpc/mm/pgtable_64.c
+++ b/arch/powerpc/mm/pgtable_64.c
@@ -723,7 +723,7 @@ void set_pmd_at(struct mm_struct *mm, unsigned long addr,
 	assert_spin_locked(&mm->page_table_lock);
 	WARN_ON(!pmd_trans_huge(pmd));
 #endif
-	trace_hugepage_set_pmd(addr, pmd);
+	trace_hugepage_set_pmd(addr, pmd_val(pmd));
 	return set_pte_at(mm, addr, pmdp_ptep(pmdp), pmd_pte(pmd));
 }
 
diff --git a/arch/powerpc/mm/tlb_hash64.c b/arch/powerpc/mm/tlb_hash64.c
index d2a94b85dbc2..c522969f012d 100644
--- a/arch/powerpc/mm/tlb_hash64.c
+++ b/arch/powerpc/mm/tlb_hash64.c
@@ -216,7 +216,7 @@ void __flush_hash_table_range(struct mm_struct *mm, unsigned long start,
 			continue;
 		pte = pte_val(*ptep);
 		if (hugepage_shift)
-			trace_hugepage_invalidate(start, pte_val(pte));
+			trace_hugepage_invalidate(start, pte);
 		if (!(pte & _PAGE_HASHPTE))
 			continue;
 		if (unlikely(hugepage_shift && pmd_trans_huge(*(pmd_t *)pte)))
-- 
2.1.0

[PATCH 5/6] mm/gup: Replace ACCESS_ONCE with READ_ONCE for STRICT_MM_TYPECHECKS

[Michael Ellerman]

If STRICT_MM_TYPECHECKS is enabled the generic gup code fails to build
because we are using ACCESS_ONCE on non-scalar types.

Convert all uses to READ_ONCE.

Cc: akpm@linux-foundation.org
Cc: kirill.shutemov@linux.intel.com
Cc: aarcange@redhat.com
Cc: borntraeger@de.ibm.com
Cc: steve.capper@linaro.org
Cc: linux-mm@kvack.org
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 mm/gup.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/mm/gup.c b/mm/gup.c
index a6e24e246f86..120c3adc843c 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -901,7 +901,7 @@ static int gup_pte_range(pmd_t pmd, unsigned long addr, unsigned long end,
 		 *
 		 * for an example see gup_get_pte in arch/x86/mm/gup.c
 		 */
-		pte_t pte = ACCESS_ONCE(*ptep);
+		pte_t pte = READ_ONCE(*ptep);
 		struct page *page;
 
 		/*
@@ -1191,7 +1191,7 @@ int __get_user_pages_fast(unsigned long start, int nr_pages, int write,
 	local_irq_save(flags);
 	pgdp = pgd_offset(mm, addr);
 	do {
-		pgd_t pgd = ACCESS_ONCE(*pgdp);
+		pgd_t pgd = READ_ONCE(*pgdp);
 
 		next = pgd_addr_end(addr, end);
 		if (pgd_none(pgd))
-- 
2.1.0

[RFC PATCH 6/6] powerpc: Always enable STRICT_MM_TYPECHECKS

[Michael Ellerman]

The argument for making this an option was that gcc produced inferior
code with it enabled. That doesn't seem to be the case anymore (gcc
4.9), so turn it on always.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/Kconfig.debug               |  8 -------
 arch/powerpc/include/asm/page.h          | 40 --------------------------------
 arch/powerpc/include/asm/pgtable-ppc64.h |  5 ----
 3 files changed, 53 deletions(-)

diff --git a/arch/powerpc/Kconfig.debug b/arch/powerpc/Kconfig.debug
index 777108f4acab..ec2e40f2cc11 100644
--- a/arch/powerpc/Kconfig.debug
+++ b/arch/powerpc/Kconfig.debug
@@ -19,14 +19,6 @@ config PPC_WERROR
 	depends on !PPC_DISABLE_WERROR
 	default y
 
-config STRICT_MM_TYPECHECKS
-	bool "Do extra type checking on mm types"
-	default n
-	help
-	  This option turns on extra type checking for some mm related types.
-
-	  If you don't know what this means, say N.
-
 config PRINT_STACK_DEPTH
 	int "Stack depth to print" if DEBUG_KERNEL
 	default 64
diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
index 71294a6e976e..6af9514106ab 100644
--- a/arch/powerpc/include/asm/page.h
+++ b/arch/powerpc/include/asm/page.h
@@ -278,7 +278,6 @@ extern long long virt_phys_offset;
 
 #ifndef __ASSEMBLY__
 
-#ifdef CONFIG_STRICT_MM_TYPECHECKS
 /* These are used to make use of C type-checking. */
 
 /* PTE level */
@@ -319,45 +318,6 @@ typedef struct { unsigned long pgprot; } pgprot_t;
 #define pgprot_val(x)	((x).pgprot)
 #define __pgprot(x)	((pgprot_t) { (x) })
 
-#else
-
-/*
- * .. while these make it easier on the compiler
- */
-
-typedef pte_basic_t pte_t;
-#define pte_val(x)	(x)
-#define __pte(x)	(x)
-
-#if defined(CONFIG_PPC_64K_PAGES) && defined(CONFIG_PPC_STD_MMU_64)
-typedef struct { pte_t pte; unsigned long hidx; } real_pte_t;
-#else
-typedef pte_t real_pte_t;
-#endif
-
-
-#ifdef CONFIG_PPC64
-typedef unsigned long pmd_t;
-#define pmd_val(x)	(x)
-#define __pmd(x)	(x)
-
-#ifndef CONFIG_PPC_64K_PAGES
-typedef unsigned long pud_t;
-#define pud_val(x)	(x)
-#define __pud(x)	(x)
-#endif /* !CONFIG_PPC_64K_PAGES */
-#endif /* CONFIG_PPC64 */
-
-typedef unsigned long pgd_t;
-#define pgd_val(x)	(x)
-#define pgprot_val(x)	(x)
-
-typedef unsigned long pgprot_t;
-#define __pgd(x)	(x)
-#define __pgprot(x)	(x)
-
-#endif
-
 typedef struct { signed long pd; } hugepd_t;
 
 #ifdef CONFIG_HUGETLB_PAGE
diff --git a/arch/powerpc/include/asm/pgtable-ppc64.h b/arch/powerpc/include/asm/pgtable-ppc64.h
index f951d9cf358a..4fa3035d8449 100644
--- a/arch/powerpc/include/asm/pgtable-ppc64.h
+++ b/arch/powerpc/include/asm/pgtable-ppc64.h
@@ -118,13 +118,8 @@
  */
 #ifndef __real_pte
 
-#ifdef CONFIG_STRICT_MM_TYPECHECKS
 #define __real_pte(e,p)		((real_pte_t){(e)})
 #define __rpte_to_pte(r)	((r).pte)
-#else
-#define __real_pte(e,p)		(e)
-#define __rpte_to_pte(r)	(__pte(r))
-#endif
 #define __rpte_to_hidx(r,index)	(pte_val(__rpte_to_pte(r)) >> 12)
 
 #define pte_iterate_hashed_subpages(rpte, psize, va, index, shift)       \
-- 
2.1.0

Re: [PATCH 5/6] mm/gup: Replace ACCESS_ONCE with READ_ONCE for STRICT_MM_TYPECHECKS

[Christian Borntraeger]

Am 25.03.2015 um 10:11 schrieb Michael Ellerman:
> If STRICT_MM_TYPECHECKS is enabled the generic gup code fails to build
> because we are using ACCESS_ONCE on non-scalar types.
> 
> Convert all uses to READ_ONCE.

There is a similar patch from Jason Low in Andrews patch.
If that happens in 4.0-rc, we probably want to merge this before 4.0.


> 
> Cc: akpm@linux-foundation.org
> Cc: kirill.shutemov@linux.intel.com
> Cc: aarcange@redhat.com
> Cc: borntraeger@de.ibm.com
> Cc: steve.capper@linaro.org
> Cc: linux-mm@kvack.org
> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
> ---
>  mm/gup.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/mm/gup.c b/mm/gup.c
> index a6e24e246f86..120c3adc843c 100644
> --- a/mm/gup.c
> +++ b/mm/gup.c
> @@ -901,7 +901,7 @@ static int gup_pte_range(pmd_t pmd, unsigned long addr, unsigned long end,
>  		 *
>  		 * for an example see gup_get_pte in arch/x86/mm/gup.c
>  		 */
> -		pte_t pte = ACCESS_ONCE(*ptep);
> +		pte_t pte = READ_ONCE(*ptep);
>  		struct page *page;
> 
>  		/*
> @@ -1191,7 +1191,7 @@ int __get_user_pages_fast(unsigned long start, int nr_pages, int write,
>  	local_irq_save(flags);
>  	pgdp = pgd_offset(mm, addr);
>  	do {
> -		pgd_t pgd = ACCESS_ONCE(*pgdp);
> +		pgd_t pgd = READ_ONCE(*pgdp);
> 
>  		next = pgd_addr_end(addr, end);
>  		if (pgd_none(pgd))
> 

Re: [PATCH 5/6] mm/gup: Replace ACCESS_ONCE with READ_ONCE for STRICT_MM_TYPECHECKS

[Michael Ellerman]

On Wed, 2015-03-25 at 10:18 +0100, Christian Borntraeger wrote:
> Am 25.03.2015 um 10:11 schrieb Michael Ellerman:
> > If STRICT_MM_TYPECHECKS is enabled the generic gup code fails to build
> > because we are using ACCESS_ONCE on non-scalar types.
> > 
> > Convert all uses to READ_ONCE.
> 
> There is a similar patch from Jason Low in Andrews patch.

Ah sorry, I didn't think to check.

> If that happens in 4.0-rc, we probably want to merge this before 4.0.

My series can wait, it's not urgent. So I'll plan to merge mine once Andrew's
tree has gone into Linus' tree for 4.1.

cheers