[PATCH v4 20/36] powerpc: Implement the new page table range API

From: Matthew Wilcox (Oracle)
Date: Wed Mar 15 2023 - 01:16:31 EST


Add set_ptes(), update_mmu_cache_range() and flush_dcache_folio().
Change the PG_arch_1 (aka PG_dcache_dirty) flag from being per-page to
per-folio.

Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Nicholas Piggin <npiggin@xxxxxxxxx>
Cc: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
---
arch/powerpc/include/asm/book3s/pgtable.h | 10 +----
arch/powerpc/include/asm/cacheflush.h | 14 +++++--
arch/powerpc/include/asm/kvm_ppc.h | 10 ++---
arch/powerpc/include/asm/nohash/pgtable.h | 13 ++----
arch/powerpc/include/asm/pgtable.h | 6 +++
arch/powerpc/mm/book3s64/hash_utils.c | 11 ++---
arch/powerpc/mm/cacheflush.c | 40 ++++++------------
arch/powerpc/mm/nohash/e500_hugetlbpage.c | 3 +-
arch/powerpc/mm/pgtable.c | 51 +++++++++++++----------
9 files changed, 77 insertions(+), 81 deletions(-)

diff --git a/arch/powerpc/include/asm/book3s/pgtable.h b/arch/powerpc/include/asm/book3s/pgtable.h
index d18b748ea3ae..c2ef811505b0 100644
--- a/arch/powerpc/include/asm/book3s/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/pgtable.h
@@ -9,13 +9,6 @@
#endif

#ifndef __ASSEMBLY__
-/* Insert a PTE, top-level function is out of line. It uses an inline
- * low level function in the respective pgtable-* files
- */
-extern void set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep,
- pte_t pte);
-
-
#define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
extern int ptep_set_access_flags(struct vm_area_struct *vma, unsigned long address,
pte_t *ptep, pte_t entry, int dirty);
@@ -36,7 +29,8 @@ void __update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t
* corresponding HPTE into the hash table ahead of time, instead of
* waiting for the inevitable extra hash-table miss exception.
*/
-static inline void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *ptep)
+static inline void update_mmu_cache_range(struct vm_area_struct *vma,
+ unsigned long address, pte_t *ptep, unsigned int nr)
{
if (IS_ENABLED(CONFIG_PPC32) && !mmu_has_feature(MMU_FTR_HPTE_TABLE))
return;
diff --git a/arch/powerpc/include/asm/cacheflush.h b/arch/powerpc/include/asm/cacheflush.h
index 7564dd4fd12b..ef7d2de33b89 100644
--- a/arch/powerpc/include/asm/cacheflush.h
+++ b/arch/powerpc/include/asm/cacheflush.h
@@ -35,13 +35,19 @@ static inline void flush_cache_vmap(unsigned long start, unsigned long end)
* It just marks the page as not i-cache clean. We do the i-cache
* flush later when the page is given to a user process, if necessary.
*/
-static inline void flush_dcache_page(struct page *page)
+static inline void flush_dcache_folio(struct folio *folio)
{
if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
return;
/* avoid an atomic op if possible */
- if (test_bit(PG_dcache_clean, &page->flags))
- clear_bit(PG_dcache_clean, &page->flags);
+ if (test_bit(PG_dcache_clean, &folio->flags))
+ clear_bit(PG_dcache_clean, &folio->flags);
+}
+#define flush_dcache_folio flush_dcache_folio
+
+static inline void flush_dcache_page(struct page *page)
+{
+ flush_dcache_folio(page_folio(page));
}

void flush_icache_range(unsigned long start, unsigned long stop);
@@ -51,7 +57,7 @@ void flush_icache_user_page(struct vm_area_struct *vma, struct page *page,
unsigned long addr, int len);
#define flush_icache_user_page flush_icache_user_page

-void flush_dcache_icache_page(struct page *page);
+void flush_dcache_icache_folio(struct folio *folio);

/**
* flush_dcache_range(): Write any modified data cache blocks out to memory and
diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
index 6bef23d6d0e3..e91dd8e88bb7 100644
--- a/arch/powerpc/include/asm/kvm_ppc.h
+++ b/arch/powerpc/include/asm/kvm_ppc.h
@@ -868,7 +868,7 @@ void kvmppc_init_lpid(unsigned long nr_lpids);

static inline void kvmppc_mmu_flush_icache(kvm_pfn_t pfn)
{
- struct page *page;
+ struct folio *folio;
/*
* We can only access pages that the kernel maps
* as memory. Bail out for unmapped ones.
@@ -877,10 +877,10 @@ static inline void kvmppc_mmu_flush_icache(kvm_pfn_t pfn)
return;

/* Clear i-cache for new pages */
- page = pfn_to_page(pfn);
- if (!test_bit(PG_dcache_clean, &page->flags)) {
- flush_dcache_icache_page(page);
- set_bit(PG_dcache_clean, &page->flags);
+ folio = page_folio(pfn_to_page(pfn));
+ if (!test_bit(PG_dcache_clean, &folio->flags)) {
+ flush_dcache_icache_folio(folio);
+ set_bit(PG_dcache_clean, &folio->flags);
}
}

diff --git a/arch/powerpc/include/asm/nohash/pgtable.h b/arch/powerpc/include/asm/nohash/pgtable.h
index a6caaaab6f92..69a7dd47a9f0 100644
--- a/arch/powerpc/include/asm/nohash/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/pgtable.h
@@ -166,12 +166,6 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
return __pte(pte_val(pte) & ~_PAGE_SWP_EXCLUSIVE);
}

-/* Insert a PTE, top-level function is out of line. It uses an inline
- * low level function in the respective pgtable-* files
- */
-extern void set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep,
- pte_t pte);
-
/* This low level function performs the actual PTE insertion
* Setting the PTE depends on the MMU type and other factors. It's
* an horrible mess that I'm not going to try to clean up now but
@@ -282,10 +276,11 @@ static inline int pud_huge(pud_t pud)
* for the page which has just been mapped in.
*/
#if defined(CONFIG_PPC_E500) && defined(CONFIG_HUGETLB_PAGE)
-void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *ptep);
+void update_mmu_cache_range(struct vm_area_struct *vma, unsigned long address,
+ pte_t *ptep, unsigned int nr);
#else
-static inline
-void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *ptep) {}
+static inline void update_mmu_cache(struct vm_area_struct *vma,
+ unsigned long address, pte_t *ptep, unsigned int nr) {}
#endif

#endif /* __ASSEMBLY__ */
diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h
index 9972626ddaf6..656ecf2b10cd 100644
--- a/arch/powerpc/include/asm/pgtable.h
+++ b/arch/powerpc/include/asm/pgtable.h
@@ -41,6 +41,12 @@ struct mm_struct;

#ifndef __ASSEMBLY__

+void set_ptes(struct mm_struct *mm, unsigned long addr, pte_t *ptep,
+ pte_t pte, unsigned int nr);
+#define set_ptes set_ptes
+#define update_mmu_cache(vma, addr, ptep) \
+ update_mmu_cache_range(vma, addr, ptep, 1)
+
#ifndef MAX_PTRS_PER_PGD
#define MAX_PTRS_PER_PGD PTRS_PER_PGD
#endif
diff --git a/arch/powerpc/mm/book3s64/hash_utils.c b/arch/powerpc/mm/book3s64/hash_utils.c
index fedffe3ae136..ad2afa08e62e 100644
--- a/arch/powerpc/mm/book3s64/hash_utils.c
+++ b/arch/powerpc/mm/book3s64/hash_utils.c
@@ -1307,18 +1307,19 @@ void hash__early_init_mmu_secondary(void)
*/
unsigned int hash_page_do_lazy_icache(unsigned int pp, pte_t pte, int trap)
{
- struct page *page;
+ struct folio *folio;

if (!pfn_valid(pte_pfn(pte)))
return pp;

- page = pte_page(pte);
+ folio = page_folio(pte_page(pte));

/* page is dirty */
- if (!test_bit(PG_dcache_clean, &page->flags) && !PageReserved(page)) {
+ if (!test_bit(PG_dcache_clean, &folio->flags) &&
+ !folio_test_reserved(folio)) {
if (trap == INTERRUPT_INST_STORAGE) {
- flush_dcache_icache_page(page);
- set_bit(PG_dcache_clean, &page->flags);
+ flush_dcache_icache_folio(folio);
+ set_bit(PG_dcache_clean, &folio->flags);
} else
pp |= HPTE_R_N;
}
diff --git a/arch/powerpc/mm/cacheflush.c b/arch/powerpc/mm/cacheflush.c
index 0e9b4879c0f9..8760d2223abe 100644
--- a/arch/powerpc/mm/cacheflush.c
+++ b/arch/powerpc/mm/cacheflush.c
@@ -148,44 +148,30 @@ static void __flush_dcache_icache(void *p)
invalidate_icache_range(addr, addr + PAGE_SIZE);
}

-static void flush_dcache_icache_hugepage(struct page *page)
+void flush_dcache_icache_folio(struct folio *folio)
{
- int i;
- int nr = compound_nr(page);
+ unsigned int i, nr = folio_nr_pages(folio);

- if (!PageHighMem(page)) {
+ if (flush_coherent_icache())
+ return;
+
+ if (!folio_test_highmem(folio)) {
+ void *addr = folio_address(folio);
for (i = 0; i < nr; i++)
- __flush_dcache_icache(lowmem_page_address(page + i));
- } else {
+ __flush_dcache_icache(addr + i * PAGE_SIZE);
+ } else if (IS_ENABLED(CONFIG_BOOKE) || sizeof(phys_addr_t) > sizeof(void *)) {
for (i = 0; i < nr; i++) {
- void *start = kmap_local_page(page + i);
+ void *start = kmap_local_folio(folio, i * PAGE_SIZE);

__flush_dcache_icache(start);
kunmap_local(start);
}
- }
-}
-
-void flush_dcache_icache_page(struct page *page)
-{
- if (flush_coherent_icache())
- return;
-
- if (PageCompound(page))
- return flush_dcache_icache_hugepage(page);
-
- if (!PageHighMem(page)) {
- __flush_dcache_icache(lowmem_page_address(page));
- } else if (IS_ENABLED(CONFIG_BOOKE) || sizeof(phys_addr_t) > sizeof(void *)) {
- void *start = kmap_local_page(page);
-
- __flush_dcache_icache(start);
- kunmap_local(start);
} else {
- flush_dcache_icache_phys(page_to_phys(page));
+ unsigned long pfn = folio_pfn(folio);
+ for (i = 0; i < nr; i++)
+ flush_dcache_icache_phys((pfn + i) * PAGE_SIZE);
}
}
-EXPORT_SYMBOL(flush_dcache_icache_page);

void clear_user_page(void *page, unsigned long vaddr, struct page *pg)
{
diff --git a/arch/powerpc/mm/nohash/e500_hugetlbpage.c b/arch/powerpc/mm/nohash/e500_hugetlbpage.c
index 58c8d9849cb1..f3cb91107a47 100644
--- a/arch/powerpc/mm/nohash/e500_hugetlbpage.c
+++ b/arch/powerpc/mm/nohash/e500_hugetlbpage.c
@@ -178,7 +178,8 @@ book3e_hugetlb_preload(struct vm_area_struct *vma, unsigned long ea, pte_t pte)
*
* This must always be called with the pte lock held.
*/
-void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *ptep)
+void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
+ pte_t *ptep, unsigned int nr)
{
if (is_vm_hugetlb_page(vma))
book3e_hugetlb_preload(vma, address, *ptep);
diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c
index cb2dcdb18f8e..b3c7b874a7a2 100644
--- a/arch/powerpc/mm/pgtable.c
+++ b/arch/powerpc/mm/pgtable.c
@@ -58,7 +58,7 @@ static inline int pte_looks_normal(pte_t pte)
return 0;
}

-static struct page *maybe_pte_to_page(pte_t pte)
+static struct folio *maybe_pte_to_folio(pte_t pte)
{
unsigned long pfn = pte_pfn(pte);
struct page *page;
@@ -68,7 +68,7 @@ static struct page *maybe_pte_to_page(pte_t pte)
page = pfn_to_page(pfn);
if (PageReserved(page))
return NULL;
- return page;
+ return page_folio(page);
}

#ifdef CONFIG_PPC_BOOK3S
@@ -84,12 +84,12 @@ static pte_t set_pte_filter_hash(pte_t pte)
pte = __pte(pte_val(pte) & ~_PAGE_HPTEFLAGS);
if (pte_looks_normal(pte) && !(cpu_has_feature(CPU_FTR_COHERENT_ICACHE) ||
cpu_has_feature(CPU_FTR_NOEXECUTE))) {
- struct page *pg = maybe_pte_to_page(pte);
- if (!pg)
+ struct folio *folio = maybe_pte_to_folio(pte);
+ if (!folio)
return pte;
- if (!test_bit(PG_dcache_clean, &pg->flags)) {
- flush_dcache_icache_page(pg);
- set_bit(PG_dcache_clean, &pg->flags);
+ if (!test_bit(PG_dcache_clean, &folio->flags)) {
+ flush_dcache_icache_folio(folio);
+ set_bit(PG_dcache_clean, &folio->flags);
}
}
return pte;
@@ -107,7 +107,7 @@ static pte_t set_pte_filter_hash(pte_t pte) { return pte; }
*/
static inline pte_t set_pte_filter(pte_t pte)
{
- struct page *pg;
+ struct folio *folio;

if (radix_enabled())
return pte;
@@ -120,18 +120,18 @@ static inline pte_t set_pte_filter(pte_t pte)
return pte;

/* If you set _PAGE_EXEC on weird pages you're on your own */
- pg = maybe_pte_to_page(pte);
- if (unlikely(!pg))
+ folio = maybe_pte_to_folio(pte);
+ if (unlikely(!folio))
return pte;

/* If the page clean, we move on */
- if (test_bit(PG_dcache_clean, &pg->flags))
+ if (test_bit(PG_dcache_clean, &folio->flags))
return pte;

/* If it's an exec fault, we flush the cache and make it clean */
if (is_exec_fault()) {
- flush_dcache_icache_page(pg);
- set_bit(PG_dcache_clean, &pg->flags);
+ flush_dcache_icache_folio(folio);
+ set_bit(PG_dcache_clean, &folio->flags);
return pte;
}

@@ -142,7 +142,7 @@ static inline pte_t set_pte_filter(pte_t pte)
static pte_t set_access_flags_filter(pte_t pte, struct vm_area_struct *vma,
int dirty)
{
- struct page *pg;
+ struct folio *folio;

if (IS_ENABLED(CONFIG_PPC_BOOK3S_64))
return pte;
@@ -168,17 +168,17 @@ static pte_t set_access_flags_filter(pte_t pte, struct vm_area_struct *vma,
#endif /* CONFIG_DEBUG_VM */

/* If you set _PAGE_EXEC on weird pages you're on your own */
- pg = maybe_pte_to_page(pte);
- if (unlikely(!pg))
+ folio = maybe_pte_to_folio(pte);
+ if (unlikely(!folio))
goto bail;

/* If the page is already clean, we move on */
- if (test_bit(PG_dcache_clean, &pg->flags))
+ if (test_bit(PG_dcache_clean, &folio->flags))
goto bail;

/* Clean the page and set PG_dcache_clean */
- flush_dcache_icache_page(pg);
- set_bit(PG_dcache_clean, &pg->flags);
+ flush_dcache_icache_folio(folio);
+ set_bit(PG_dcache_clean, &folio->flags);

bail:
return pte_mkexec(pte);
@@ -187,8 +187,8 @@ static pte_t set_access_flags_filter(pte_t pte, struct vm_area_struct *vma,
/*
* set_pte stores a linux PTE into the linux page table.
*/
-void set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep,
- pte_t pte)
+void set_ptes(struct mm_struct *mm, unsigned long addr, pte_t *ptep,
+ pte_t pte, unsigned int nr)
{
/*
* Make sure hardware valid bit is not set. We don't do
@@ -203,7 +203,14 @@ void set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep,
pte = set_pte_filter(pte);

/* Perform the setting of the PTE */
- __set_pte_at(mm, addr, ptep, pte, 0);
+ for (;;) {
+ __set_pte_at(mm, addr, ptep, pte, 0);
+ if (--nr == 0)
+ break;
+ ptep++;
+ pte = __pte(pte_val(pte) + PAGE_SIZE);
+ addr += PAGE_SIZE;
+ }
}

void unmap_kernel_page(unsigned long va)
--
2.39.2