[PATCH v7 08/16] powerpc/mm: Extend pte_fragment functionality to PPC32

From: Christophe Leroy
Date: Wed Nov 28 2018 - 06:47:23 EST


In order to allow the 8xx to handle pte_fragments, this patch
extends the use of pte_fragments to PPC32 platforms.

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
---
arch/powerpc/include/asm/book3s/32/mmu-hash.h | 5 ++++-
arch/powerpc/include/asm/book3s/32/pgalloc.h | 18 ++++++++++--------
arch/powerpc/include/asm/book3s/32/pgtable.h | 5 +++--
arch/powerpc/include/asm/mmu_context.h | 2 +-
arch/powerpc/include/asm/nohash/32/mmu.h | 4 +++-
arch/powerpc/include/asm/nohash/32/pgalloc.h | 23 ++++++++++++-----------
arch/powerpc/include/asm/nohash/32/pgtable.h | 8 +++++---
arch/powerpc/mm/Makefile | 1 +
arch/powerpc/mm/mmu_context.c | 10 ++++++++++
arch/powerpc/mm/mmu_context_nohash.c | 2 +-
arch/powerpc/mm/pgtable_32.c | 25 ++++---------------------
11 files changed, 54 insertions(+), 49 deletions(-)

diff --git a/arch/powerpc/include/asm/book3s/32/mmu-hash.h b/arch/powerpc/include/asm/book3s/32/mmu-hash.h
index 5bd26c218b94..2bb500d25de6 100644
--- a/arch/powerpc/include/asm/book3s/32/mmu-hash.h
+++ b/arch/powerpc/include/asm/book3s/32/mmu-hash.h
@@ -1,6 +1,7 @@
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_POWERPC_BOOK3S_32_MMU_HASH_H_
#define _ASM_POWERPC_BOOK3S_32_MMU_HASH_H_
+
/*
* 32-bit hash table MMU support
*/
@@ -9,6 +10,8 @@
* BATs
*/

+#include <asm/page.h>
+
/* Block size masks */
#define BL_128K 0x000
#define BL_256K 0x001
@@ -43,7 +46,7 @@ struct ppc_bat {
u32 batl;
};

-typedef struct page *pgtable_t;
+typedef pte_t *pgtable_t;
#endif /* !__ASSEMBLY__ */

/*
diff --git a/arch/powerpc/include/asm/book3s/32/pgalloc.h b/arch/powerpc/include/asm/book3s/32/pgalloc.h
index a70f3cf16dc8..56e805107352 100644
--- a/arch/powerpc/include/asm/book3s/32/pgalloc.h
+++ b/arch/powerpc/include/asm/book3s/32/pgalloc.h
@@ -27,6 +27,10 @@ extern void __bad_pte(pmd_t *pmd);
extern struct kmem_cache *pgtable_cache[];
#define PGT_CACHE(shift) pgtable_cache[shift]

+void pte_frag_destroy(void *pte_frag);
+pte_t *pte_fragment_alloc(struct mm_struct *mm, unsigned long vmaddr, int kernel);
+void pte_fragment_free(unsigned long *table, int kernel);
+
static inline pgd_t *pgd_alloc(struct mm_struct *mm)
{
return kmem_cache_alloc(PGT_CACHE(PGD_INDEX_SIZE),
@@ -56,30 +60,28 @@ static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp,
static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmdp,
pgtable_t pte_page)
{
- *pmdp = __pmd((page_to_pfn(pte_page) << PAGE_SHIFT) | _PMD_PRESENT);
+ *pmdp = __pmd(__pa(pte_page) | _PMD_PRESENT);
}

-#define pmd_pgtable(pmd) pmd_page(pmd)
+#define pmd_pgtable(pmd) ((pgtable_t)pmd_page_vaddr(pmd))

extern pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr);
extern pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long addr);

static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
{
- free_page((unsigned long)pte);
+ pte_fragment_free((unsigned long *)pte, 1);
}

static inline void pte_free(struct mm_struct *mm, pgtable_t ptepage)
{
- pgtable_page_dtor(ptepage);
- __free_page(ptepage);
+ pte_fragment_free((unsigned long *)ptepage, 0);
}

static inline void pgtable_free(void *table, unsigned index_size)
{
if (!index_size) {
- pgtable_page_dtor(virt_to_page(table));
- free_page((unsigned long)table);
+ pte_fragment_free((unsigned long *)table, 0);
} else {
BUG_ON(index_size > MAX_PGTABLE_INDEX_SIZE);
kmem_cache_free(PGT_CACHE(index_size), table);
@@ -117,6 +119,6 @@ static inline void pgtable_free_tlb(struct mmu_gather *tlb,
static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t table,
unsigned long address)
{
- pgtable_free_tlb(tlb, page_address(table), 0);
+ pgtable_free_tlb(tlb, table, 0);
}
#endif /* _ASM_POWERPC_BOOK3S_32_PGALLOC_H */
diff --git a/arch/powerpc/include/asm/book3s/32/pgtable.h b/arch/powerpc/include/asm/book3s/32/pgtable.h
index 32c33eccc0e2..47156b93f9af 100644
--- a/arch/powerpc/include/asm/book3s/32/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/32/pgtable.h
@@ -329,7 +329,7 @@ static inline void __ptep_set_access_flags(struct vm_area_struct *vma,
#define pte_same(A,B) (((pte_val(A) ^ pte_val(B)) & ~_PAGE_HASHPTE) == 0)

#define pmd_page_vaddr(pmd) \
- ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
+ ((unsigned long)__va(pmd_val(pmd) & ~(PTE_TABLE_SIZE - 1)))
#define pmd_page(pmd) \
pfn_to_page(pmd_val(pmd) >> PAGE_SHIFT)

@@ -346,7 +346,8 @@ static inline void __ptep_set_access_flags(struct vm_area_struct *vma,
#define pte_offset_kernel(dir, addr) \
((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(addr))
#define pte_offset_map(dir, addr) \
- ((pte_t *) kmap_atomic(pmd_page(*(dir))) + pte_index(addr))
+ ((pte_t *)(kmap_atomic(pmd_page(*(dir))) + \
+ (pmd_page_vaddr(*(dir)) & ~PAGE_MASK)) + pte_index(addr))
#define pte_unmap(pte) kunmap_atomic(pte)

/*
diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h
index 0381394a425b..c05efd2e8736 100644
--- a/arch/powerpc/include/asm/mmu_context.h
+++ b/arch/powerpc/include/asm/mmu_context.h
@@ -223,7 +223,7 @@ static inline int arch_dup_mmap(struct mm_struct *oldmm,
return 0;
}

-#ifndef CONFIG_PPC_BOOK3S_64
+#ifdef CONFIG_PPC_BOOK3E_64
static inline void arch_exit_mmap(struct mm_struct *mm)
{
}
diff --git a/arch/powerpc/include/asm/nohash/32/mmu.h b/arch/powerpc/include/asm/nohash/32/mmu.h
index f61f933a4cd8..7d94a36d57d2 100644
--- a/arch/powerpc/include/asm/nohash/32/mmu.h
+++ b/arch/powerpc/include/asm/nohash/32/mmu.h
@@ -2,6 +2,8 @@
#ifndef _ASM_POWERPC_NOHASH_32_MMU_H_
#define _ASM_POWERPC_NOHASH_32_MMU_H_

+#include <asm/page.h>
+
#if defined(CONFIG_40x)
/* 40x-style software loaded TLB */
#include <asm/nohash/32/mmu-40x.h>
@@ -17,7 +19,7 @@
#endif

#ifndef __ASSEMBLY__
-typedef struct page *pgtable_t;
+typedef pte_t *pgtable_t;
#endif

#endif /* _ASM_POWERPC_NOHASH_32_MMU_H_ */
diff --git a/arch/powerpc/include/asm/nohash/32/pgalloc.h b/arch/powerpc/include/asm/nohash/32/pgalloc.h
index 6fbbb90043c0..7b8d0a3ab0fd 100644
--- a/arch/powerpc/include/asm/nohash/32/pgalloc.h
+++ b/arch/powerpc/include/asm/nohash/32/pgalloc.h
@@ -27,6 +27,10 @@ extern void __bad_pte(pmd_t *pmd);
extern struct kmem_cache *pgtable_cache[];
#define PGT_CACHE(shift) pgtable_cache[shift]

+void pte_frag_destroy(void *pte_frag);
+pte_t *pte_fragment_alloc(struct mm_struct *mm, unsigned long vmaddr, int kernel);
+void pte_fragment_free(unsigned long *table, int kernel);
+
static inline pgd_t *pgd_alloc(struct mm_struct *mm)
{
return kmem_cache_alloc(PGT_CACHE(PGD_INDEX_SIZE),
@@ -58,11 +62,10 @@ static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp,
static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmdp,
pgtable_t pte_page)
{
- *pmdp = __pmd((page_to_pfn(pte_page) << PAGE_SHIFT) | _PMD_USER |
- _PMD_PRESENT);
+ *pmdp = __pmd(__pa(pte_page) | _PMD_USER | _PMD_PRESENT);
}

-#define pmd_pgtable(pmd) pmd_page(pmd)
+#define pmd_pgtable(pmd) ((pgtable_t)pmd_page_vaddr(pmd))
#else

static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp,
@@ -74,10 +77,10 @@ static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp,
static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmdp,
pgtable_t pte_page)
{
- *pmdp = __pmd((unsigned long)lowmem_page_address(pte_page) | _PMD_PRESENT);
+ *pmdp = __pmd((unsigned long)pte_page | _PMD_PRESENT);
}

-#define pmd_pgtable(pmd) pmd_page(pmd)
+#define pmd_pgtable(pmd) ((pgtable_t)pmd_page_vaddr(pmd))
#endif

extern pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr);
@@ -85,20 +88,18 @@ extern pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long addr);

static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
{
- free_page((unsigned long)pte);
+ pte_fragment_free((unsigned long *)pte, 1);
}

static inline void pte_free(struct mm_struct *mm, pgtable_t ptepage)
{
- pgtable_page_dtor(ptepage);
- __free_page(ptepage);
+ pte_fragment_free((unsigned long *)ptepage, 0);
}

static inline void pgtable_free(void *table, unsigned index_size)
{
if (!index_size) {
- pgtable_page_dtor(virt_to_page(table));
- free_page((unsigned long)table);
+ pte_fragment_free((unsigned long *)table, 0);
} else {
BUG_ON(index_size > MAX_PGTABLE_INDEX_SIZE);
kmem_cache_free(PGT_CACHE(index_size), table);
@@ -137,6 +138,6 @@ static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t table,
unsigned long address)
{
tlb_flush_pgtable(tlb, address);
- pgtable_free_tlb(tlb, page_address(table), 0);
+ pgtable_free_tlb(tlb, table, 0);
}
#endif /* _ASM_POWERPC_PGALLOC_32_H */
diff --git a/arch/powerpc/include/asm/nohash/32/pgtable.h b/arch/powerpc/include/asm/nohash/32/pgtable.h
index 3ffb0ff5a038..31a03e9a42c4 100644
--- a/arch/powerpc/include/asm/nohash/32/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/32/pgtable.h
@@ -20,6 +20,7 @@ extern int icache_44x_need_flush;
#endif /* __ASSEMBLY__ */

#define PTE_INDEX_SIZE PTE_SHIFT
+
#define PMD_INDEX_SIZE 0
#define PUD_INDEX_SIZE 0
#define PGD_INDEX_SIZE (32 - PGDIR_SHIFT)
@@ -333,12 +334,12 @@ static inline int pte_young(pte_t pte)
*/
#ifndef CONFIG_BOOKE
#define pmd_page_vaddr(pmd) \
- ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
+ ((unsigned long)__va(pmd_val(pmd) & ~(PTE_TABLE_SIZE - 1)))
#define pmd_page(pmd) \
pfn_to_page(pmd_val(pmd) >> PAGE_SHIFT)
#else
#define pmd_page_vaddr(pmd) \
- ((unsigned long) (pmd_val(pmd) & PAGE_MASK))
+ ((unsigned long)(pmd_val(pmd) & ~(PTE_TABLE_SIZE - 1)))
#define pmd_page(pmd) \
pfn_to_page((__pa(pmd_val(pmd)) >> PAGE_SHIFT))
#endif
@@ -357,7 +358,8 @@ static inline int pte_young(pte_t pte)
(pmd_bad(*(dir)) ? NULL : (pte_t *)pmd_page_vaddr(*(dir)) + \
pte_index(addr))
#define pte_offset_map(dir, addr) \
- ((pte_t *) kmap_atomic(pmd_page(*(dir))) + pte_index(addr))
+ ((pte_t *)(kmap_atomic(pmd_page(*(dir))) + \
+ (pmd_page_vaddr(*(dir)) & ~PAGE_MASK)) + pte_index(addr))
#define pte_unmap(pte) kunmap_atomic(pte)

/*
diff --git a/arch/powerpc/mm/Makefile b/arch/powerpc/mm/Makefile
index 3cbb1acf0745..c8778a640d68 100644
--- a/arch/powerpc/mm/Makefile
+++ b/arch/powerpc/mm/Makefile
@@ -18,6 +18,7 @@ obj-$(CONFIG_PPC_BOOK3E_64) += pgtable-book3e.o
obj-$(CONFIG_PPC_BOOK3S_64) += pgtable-hash64.o hash_utils_64.o slb.o \
$(hash64-y) mmu_context_book3s64.o \
pgtable-book3s64.o pgtable-frag.o
+obj-$(CONFIG_PPC32) += pgtable-frag.o
obj-$(CONFIG_PPC_RADIX_MMU) += pgtable-radix.o tlb-radix.o
obj-$(CONFIG_PPC_STD_MMU_32) += ppc_mmu_32.o hash_low_32.o mmu_context_hash32.o
obj-$(CONFIG_PPC_STD_MMU) += tlb_hash$(BITS).o
diff --git a/arch/powerpc/mm/mmu_context.c b/arch/powerpc/mm/mmu_context.c
index f84e14f23e50..bb52320b7369 100644
--- a/arch/powerpc/mm/mmu_context.c
+++ b/arch/powerpc/mm/mmu_context.c
@@ -15,6 +15,7 @@
#include <linux/sched/mm.h>

#include <asm/mmu_context.h>
+#include <asm/pgalloc.h>

#if defined(CONFIG_PPC32)
static inline void switch_mm_pgdir(struct task_struct *tsk,
@@ -97,3 +98,12 @@ void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next,
switch_mmu_context(prev, next, tsk);
}

+#ifdef CONFIG_PPC32
+void arch_exit_mmap(struct mm_struct *mm)
+{
+ void *frag = pte_frag_get(&mm->context);
+
+ if (frag)
+ pte_frag_destroy(frag);
+}
+#endif
diff --git a/arch/powerpc/mm/mmu_context_nohash.c b/arch/powerpc/mm/mmu_context_nohash.c
index 2faca46ad720..431ecf37f17c 100644
--- a/arch/powerpc/mm/mmu_context_nohash.c
+++ b/arch/powerpc/mm/mmu_context_nohash.c
@@ -385,6 +385,7 @@ int init_new_context(struct task_struct *t, struct mm_struct *mm)
#endif
mm->context.id = MMU_NO_CONTEXT;
mm->context.active = 0;
+ pte_frag_set(&mm->context, NULL);
return 0;
}

@@ -487,4 +488,3 @@ void __init mmu_context_init(void)
next_context = FIRST_CONTEXT;
nr_free_contexts = LAST_CONTEXT - FIRST_CONTEXT + 1;
}
-
diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c
index bda3c6f1bd32..deb49a6e9cad 100644
--- a/arch/powerpc/mm/pgtable_32.c
+++ b/arch/powerpc/mm/pgtable_32.c
@@ -45,32 +45,15 @@ extern char etext[], _stext[], _sinittext[], _einittext[];

__ref pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
{
- pte_t *pte;
+ if (!slab_is_available())
+ return memblock_alloc(PTE_FRAG_SIZE, PTE_FRAG_SIZE);

- if (slab_is_available()) {
- pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_ZERO);
- } else {
- pte = __va(memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE));
- if (pte)
- clear_page(pte);
- }
- return pte;
+ return (pte_t *)pte_fragment_alloc(mm, address, 1);
}

pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
{
- struct page *ptepage;
-
- gfp_t flags = GFP_KERNEL | __GFP_ZERO | __GFP_ACCOUNT;
-
- ptepage = alloc_pages(flags, 0);
- if (!ptepage)
- return NULL;
- if (!pgtable_page_ctor(ptepage)) {
- __free_page(ptepage);
- return NULL;
- }
- return ptepage;
+ return (pgtable_t)pte_fragment_alloc(mm, address, 0);
}

void __iomem *
--
2.13.3