In order to fit better with standard Linux page tables layout, add support for 8M pages using contiguous PTE entries in a standard page table. Page tables will then be populated with 1024 similar entries and two PMD entries will point to that page table. The PMD entries also get a flag to tell it is addressing an 8M page, this is required for the HW tablewalk assistance. Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx> Reviewed-by: Oscar Salvador <osalvador@xxxxxxx> --- v3: - Move huge_ptep_get() for a more readable commit diff - Flag PMD as 8Mbytes in set_huge_pte_at() - Define __pte_leaf_size() - Change pte_update() instead of all huge callers of pte_update() - Added ptep_is_8m_pmdp() helper - Fixed kasan early memory 8M allocation v5: - In huge_ptep_get(), change pte_offset_kernel((pmd_t *)ptep, 0) to pte_offset_kernel((pmd_t *)ptep, ALIGN_DOWN(addr, SZ_8M)) which is more correct allthough not different. --- .../include/asm/nohash/32/hugetlb-8xx.h | 38 +++---------- arch/powerpc/include/asm/nohash/32/pte-8xx.h | 53 ++++++++++++------- arch/powerpc/include/asm/nohash/pgtable.h | 4 -- arch/powerpc/include/asm/page.h | 5 -- arch/powerpc/include/asm/pgtable.h | 3 ++ arch/powerpc/kernel/head_8xx.S | 10 +--- arch/powerpc/mm/hugetlbpage.c | 21 +++++--- arch/powerpc/mm/kasan/8xx.c | 21 +++++--- arch/powerpc/mm/nohash/8xx.c | 40 +++++++------- arch/powerpc/mm/pgtable.c | 27 +++++++--- arch/powerpc/mm/pgtable_32.c | 2 +- arch/powerpc/platforms/Kconfig.cputype | 1 - 12 files changed, 111 insertions(+), 114 deletions(-) diff --git a/arch/powerpc/include/asm/nohash/32/hugetlb-8xx.h b/arch/powerpc/include/asm/nohash/32/hugetlb-8xx.h index 92df40c6cc6b..014799557f60 100644 --- a/arch/powerpc/include/asm/nohash/32/hugetlb-8xx.h +++ b/arch/powerpc/include/asm/nohash/32/hugetlb-8xx.h @@ -4,42 +4,12 @@ #define PAGE_SHIFT_8M 23 -static inline pte_t *hugepd_page(hugepd_t hpd) -{ - BUG_ON(!hugepd_ok(hpd)); - - return (pte_t *)__va(hpd_val(hpd) & ~HUGEPD_SHIFT_MASK); -} - -static inline unsigned int hugepd_shift(hugepd_t hpd) -{ - return PAGE_SHIFT_8M; -} - -static inline pte_t *hugepte_offset(hugepd_t hpd, unsigned long addr, - unsigned int pdshift) -{ - unsigned long idx = (addr & (SZ_4M - 1)) >> PAGE_SHIFT; - - return hugepd_page(hpd) + idx; -} - static inline void flush_hugetlb_page(struct vm_area_struct *vma, unsigned long vmaddr) { flush_tlb_page(vma, vmaddr); } -static inline void hugepd_populate(hugepd_t *hpdp, pte_t *new, unsigned int pshift) -{ - *hpdp = __hugepd(__pa(new) | _PMD_USER | _PMD_PRESENT | _PMD_PAGE_8M); -} - -static inline void hugepd_populate_kernel(hugepd_t *hpdp, pte_t *new, unsigned int pshift) -{ - *hpdp = __hugepd(__pa(new) | _PMD_PRESENT | _PMD_PAGE_8M); -} - static inline int check_and_get_huge_psize(int shift) { return shift_to_mmu_psize(shift); @@ -49,6 +19,14 @@ static inline int check_and_get_huge_psize(int shift) void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, pte_t pte, unsigned long sz); +#define __HAVE_ARCH_HUGE_PTEP_GET +static inline pte_t huge_ptep_get(struct mm_struct *mm, unsigned long addr, pte_t *ptep) +{ + if (ptep_is_8m_pmdp(mm, addr, ptep)) + ptep = pte_offset_kernel((pmd_t *)ptep, ALIGN_DOWN(addr, SZ_8M)); + return ptep_get(ptep); +} + #define __HAVE_ARCH_HUGE_PTE_CLEAR static inline void huge_pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep, unsigned long sz) diff --git a/arch/powerpc/include/asm/nohash/32/pte-8xx.h b/arch/powerpc/include/asm/nohash/32/pte-8xx.h index 625c31d6ce5c..54ebb91dbdcf 100644 --- a/arch/powerpc/include/asm/nohash/32/pte-8xx.h +++ b/arch/powerpc/include/asm/nohash/32/pte-8xx.h @@ -119,7 +119,7 @@ static inline pte_t pte_mkhuge(pte_t pte) #define pte_mkhuge pte_mkhuge -static inline pte_basic_t pte_update(struct mm_struct *mm, unsigned long addr, pte_t *p, +static inline pte_basic_t pte_update(struct mm_struct *mm, unsigned long addr, pte_t *ptep, unsigned long clr, unsigned long set, int huge); static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep) @@ -141,19 +141,12 @@ static inline void __ptep_set_access_flags(struct vm_area_struct *vma, pte_t *pt } #define __ptep_set_access_flags __ptep_set_access_flags -static inline unsigned long pgd_leaf_size(pgd_t pgd) -{ - if (pgd_val(pgd) & _PMD_PAGE_8M) - return SZ_8M; - return SZ_4M; -} - -#define pgd_leaf_size pgd_leaf_size - -static inline unsigned long pte_leaf_size(pte_t pte) +static inline unsigned long __pte_leaf_size(pmd_t pmd, pte_t pte) { pte_basic_t val = pte_val(pte); + if (pmd_val(pmd) & _PMD_PAGE_8M) + return SZ_8M; if (val & _PAGE_HUGE) return SZ_512K; if (val & _PAGE_SPS) @@ -161,31 +154,38 @@ static inline unsigned long pte_leaf_size(pte_t pte) return SZ_4K; } -#define pte_leaf_size pte_leaf_size +#define __pte_leaf_size __pte_leaf_size /* * On the 8xx, the page tables are a bit special. For 16k pages, we have * 4 identical entries. For 512k pages, we have 128 entries as if it was * 4k pages, but they are flagged as 512k pages for the hardware. - * For other page sizes, we have a single entry in the table. + * For 8M pages, we have 1024 entries as if it was 4M pages (PMD_SIZE) + * but they are flagged as 8M pages for the hardware. + * For 4k pages, we have a single entry in the table. */ static pmd_t *pmd_off(struct mm_struct *mm, unsigned long addr); -static int hugepd_ok(hugepd_t hpd); +static inline pte_t *pte_offset_kernel(pmd_t *pmd, unsigned long address); + +static inline bool ptep_is_8m_pmdp(struct mm_struct *mm, unsigned long addr, pte_t *ptep) +{ + return (pmd_t *)ptep == pmd_off(mm, ALIGN_DOWN(addr, SZ_8M)); +} static inline int number_of_cells_per_pte(pmd_t *pmd, pte_basic_t val, int huge) { if (!huge) return PAGE_SIZE / SZ_4K; - else if (hugepd_ok(*((hugepd_t *)pmd))) - return 1; + else if ((pmd_val(*pmd) & _PMD_PAGE_MASK) == _PMD_PAGE_8M) + return SZ_4M / SZ_4K; else if (IS_ENABLED(CONFIG_PPC_4K_PAGES) && !(val & _PAGE_HUGE)) return SZ_16K / SZ_4K; else return SZ_512K / SZ_4K; } -static inline pte_basic_t pte_update(struct mm_struct *mm, unsigned long addr, pte_t *p, - unsigned long clr, unsigned long set, int huge) +static inline pte_basic_t __pte_update(struct mm_struct *mm, unsigned long addr, pte_t *p, + unsigned long clr, unsigned long set, int huge) { pte_basic_t *entry = (pte_basic_t *)p; pte_basic_t old = pte_val(*p); @@ -197,7 +197,7 @@ static inline pte_basic_t pte_update(struct mm_struct *mm, unsigned long addr, p for (i = 0; i < num; i += PAGE_SIZE / SZ_4K, new += PAGE_SIZE) { *entry++ = new; - if (IS_ENABLED(CONFIG_PPC_16K_PAGES) && num != 1) { + if (IS_ENABLED(CONFIG_PPC_16K_PAGES)) { *entry++ = new; *entry++ = new; *entry++ = new; @@ -207,6 +207,21 @@ static inline pte_basic_t pte_update(struct mm_struct *mm, unsigned long addr, p return old; } +static inline pte_basic_t pte_update(struct mm_struct *mm, unsigned long addr, pte_t *ptep, + unsigned long clr, unsigned long set, int huge) +{ + pte_basic_t old; + + if (huge && ptep_is_8m_pmdp(mm, addr, ptep)) { + pmd_t *pmdp = (pmd_t *)ptep; + + old = __pte_update(mm, addr, pte_offset_kernel(pmdp, 0), clr, set, huge); + __pte_update(mm, addr, pte_offset_kernel(pmdp + 1, 0), clr, set, huge); + } else { + old = __pte_update(mm, addr, ptep, clr, set, huge); + } + return old; +} #define pte_update pte_update #ifdef CONFIG_PPC_16K_PAGES diff --git a/arch/powerpc/include/asm/nohash/pgtable.h b/arch/powerpc/include/asm/nohash/pgtable.h index e7fc1314c23e..90d6a0943b35 100644 --- a/arch/powerpc/include/asm/nohash/pgtable.h +++ b/arch/powerpc/include/asm/nohash/pgtable.h @@ -343,12 +343,8 @@ static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr, #ifdef CONFIG_ARCH_HAS_HUGEPD static inline int hugepd_ok(hugepd_t hpd) { -#ifdef CONFIG_PPC_8xx - return ((hpd_val(hpd) & _PMD_PAGE_MASK) == _PMD_PAGE_8M); -#else /* We clear the top bit to indicate hugepd */ return (hpd_val(hpd) && (hpd_val(hpd) & PD_HUGE) == 0); -#endif } #define is_hugepd(hpd) (hugepd_ok(hpd)) diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h index e411e5a70ea3..018c3d55232c 100644 --- a/arch/powerpc/include/asm/page.h +++ b/arch/powerpc/include/asm/page.h @@ -293,13 +293,8 @@ static inline const void *pfn_to_kaddr(unsigned long pfn) /* * Some number of bits at the level of the page table that points to * a hugepte are used to encode the size. This masks those bits. - * On 8xx, HW assistance requires 4k alignment for the hugepte. */ -#ifdef CONFIG_PPC_8xx -#define HUGEPD_SHIFT_MASK 0xfff -#else #define HUGEPD_SHIFT_MASK 0x3f -#endif #ifndef __ASSEMBLY__ diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h index 239709a2f68e..264a6c09517a 100644 --- a/arch/powerpc/include/asm/pgtable.h +++ b/arch/powerpc/include/asm/pgtable.h @@ -106,6 +106,9 @@ unsigned long vmalloc_to_phys(void *vmalloc_addr); void pgtable_cache_add(unsigned int shift); +#ifdef CONFIG_PPC32 +void __init *early_alloc_pgtable(unsigned long size); +#endif pte_t *early_pte_alloc_kernel(pmd_t *pmdp, unsigned long va); #if defined(CONFIG_STRICT_KERNEL_RWX) || defined(CONFIG_PPC32) diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S index edc479a7c2bc..ac74321b1192 100644 --- a/arch/powerpc/kernel/head_8xx.S +++ b/arch/powerpc/kernel/head_8xx.S @@ -415,14 +415,13 @@ FixupDAR:/* Entry point for dcbx workaround. */ oris r11, r11, (swapper_pg_dir - PAGE_OFFSET)@ha 3: lwz r11, (swapper_pg_dir-PAGE_OFFSET)@l(r11) /* Get the level 1 entry */ + rlwinm r11, r11, 0, ~_PMD_PAGE_8M mtspr SPRN_MD_TWC, r11 - mtcrf 0x01, r11 mfspr r11, SPRN_MD_TWC lwz r11, 0(r11) /* Get the pte */ - bt 28,200f /* bit 28 = Large page (8M) */ /* concat physical page address(r11) and page offset(r10) */ rlwimi r11, r10, 0, 32 - PAGE_SHIFT, 31 -201: lwz r11,0(r11) + lwz r11,0(r11) /* Check if it really is a dcbx instruction. */ /* dcbt and dcbtst does not generate DTLB Misses/Errors, * no need to include them here */ @@ -441,11 +440,6 @@ FixupDAR:/* Entry point for dcbx workaround. */ 141: mfspr r10,SPRN_M_TW b DARFixed /* Nope, go back to normal TLB processing */ -200: - /* concat physical page address(r11) and page offset(r10) */ - rlwimi r11, r10, 0, 32 - PAGE_SHIFT_8M, 31 - b 201b - 144: mfspr r10, SPRN_DSISR rlwinm r10, r10,0,7,5 /* Clear store bit for buggy dcbst insn */ mtspr SPRN_DSISR, r10 diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c index 20fad59ff9f5..394846197974 100644 --- a/arch/powerpc/mm/hugetlbpage.c +++ b/arch/powerpc/mm/hugetlbpage.c @@ -183,9 +183,6 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, if (!hpdp) return NULL; - if (IS_ENABLED(CONFIG_PPC_8xx) && pshift < PMD_SHIFT) - return pte_alloc_huge(mm, (pmd_t *)hpdp, addr); - BUG_ON(!hugepd_none(*hpdp) && !hugepd_ok(*hpdp)); if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr, @@ -218,8 +215,18 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, if (!pmd) return NULL; - if (sz >= PMD_SIZE) + if (sz >= PMD_SIZE) { + /* On 8xx, all hugepages are handled as contiguous PTEs */ + if (IS_ENABLED(CONFIG_PPC_8xx)) { + int i; + + for (i = 0; i < sz / PMD_SIZE; i++) { + if (!pte_alloc_huge(mm, pmd + i, addr)) + return NULL; + } + } return (pte_t *)pmd; + } return pte_alloc_huge(mm, pmd, addr); } @@ -617,10 +624,8 @@ static int __init hugetlbpage_init(void) * use pgt cache for hugepd. */ if (pdshift > shift) { - if (!IS_ENABLED(CONFIG_PPC_8xx)) - pgtable_cache_add(pdshift - shift); - } else if (IS_ENABLED(CONFIG_PPC_E500) || - IS_ENABLED(CONFIG_PPC_8xx)) { + pgtable_cache_add(pdshift - shift); + } else if (IS_ENABLED(CONFIG_PPC_E500)) { pgtable_cache_add(PTE_T_ORDER); } diff --git a/arch/powerpc/mm/kasan/8xx.c b/arch/powerpc/mm/kasan/8xx.c index 2784224054f8..989d6cdf4141 100644 --- a/arch/powerpc/mm/kasan/8xx.c +++ b/arch/powerpc/mm/kasan/8xx.c @@ -6,28 +6,33 @@ #include <linux/memblock.h> #include <linux/hugetlb.h> +#include <asm/pgalloc.h> + static int __init kasan_init_shadow_8M(unsigned long k_start, unsigned long k_end, void *block) { pmd_t *pmd = pmd_off_k(k_start); unsigned long k_cur, k_next; - for (k_cur = k_start; k_cur != k_end; k_cur = k_next, pmd += 2, block += SZ_8M) { - pte_basic_t *new; + for (k_cur = k_start; k_cur != k_end; k_cur = k_next, pmd++, block += SZ_4M) { + pte_t *ptep; + int i; k_next = pgd_addr_end(k_cur, k_end); - k_next = pgd_addr_end(k_next, k_end); if ((void *)pmd_page_vaddr(*pmd) != kasan_early_shadow_pte) continue; - new = memblock_alloc(sizeof(pte_basic_t), SZ_4K); - if (!new) + ptep = memblock_alloc(PTE_FRAG_SIZE, PTE_FRAG_SIZE); + if (!ptep) return -ENOMEM; - *new = pte_val(pte_mkhuge(pfn_pte(PHYS_PFN(__pa(block)), PAGE_KERNEL))); + for (i = 0; i < PTRS_PER_PTE; i++) { + pte_t pte = pte_mkhuge(pfn_pte(PHYS_PFN(__pa(block + i * PAGE_SIZE)), PAGE_KERNEL)); - hugepd_populate_kernel((hugepd_t *)pmd, (pte_t *)new, PAGE_SHIFT_8M); - hugepd_populate_kernel((hugepd_t *)pmd + 1, (pte_t *)new, PAGE_SHIFT_8M); + __set_pte_at(&init_mm, k_cur, ptep + i, pte, 1); + } + pmd_populate_kernel(&init_mm, pmd, ptep); + *pmd = __pmd(pmd_val(*pmd) | _PMD_PAGE_8M); } return 0; } diff --git a/arch/powerpc/mm/nohash/8xx.c b/arch/powerpc/mm/nohash/8xx.c index d93433e26ded..388bba0ab3e7 100644 --- a/arch/powerpc/mm/nohash/8xx.c +++ b/arch/powerpc/mm/nohash/8xx.c @@ -11,6 +11,7 @@ #include <linux/hugetlb.h> #include <asm/fixmap.h> +#include <asm/pgalloc.h> #include <mm/mmu_decl.h> @@ -48,20 +49,6 @@ unsigned long p_block_mapped(phys_addr_t pa) return 0; } -static pte_t __init *early_hugepd_alloc_kernel(hugepd_t *pmdp, unsigned long va) -{ - if (hpd_val(*pmdp) == 0) { - pte_t *ptep = memblock_alloc(sizeof(pte_basic_t), SZ_4K); - - if (!ptep) - return NULL; - - hugepd_populate_kernel((hugepd_t *)pmdp, ptep, PAGE_SHIFT_8M); - hugepd_populate_kernel((hugepd_t *)pmdp + 1, ptep, PAGE_SHIFT_8M); - } - return hugepte_offset(*(hugepd_t *)pmdp, va, PGDIR_SHIFT); -} - static int __ref __early_map_kernel_hugepage(unsigned long va, phys_addr_t pa, pgprot_t prot, int psize, bool new) { @@ -75,24 +62,33 @@ static int __ref __early_map_kernel_hugepage(unsigned long va, phys_addr_t pa, if (WARN_ON(slab_is_available())) return -EINVAL; - if (psize == MMU_PAGE_512K) + if (psize == MMU_PAGE_512K) { ptep = early_pte_alloc_kernel(pmdp, va); - else - ptep = early_hugepd_alloc_kernel((hugepd_t *)pmdp, va); + /* The PTE should never be already present */ + if (WARN_ON(pte_present(*ptep) && pgprot_val(prot))) + return -EINVAL; + } else { + if (WARN_ON(!pmd_none(*pmdp) || !pmd_none(*(pmdp + 1)))) + return -EINVAL; + + ptep = early_alloc_pgtable(PTE_FRAG_SIZE); + pmd_populate_kernel(&init_mm, pmdp, ptep); + + ptep = early_alloc_pgtable(PTE_FRAG_SIZE); + pmd_populate_kernel(&init_mm, pmdp + 1, ptep); + + ptep = (pte_t *)pmdp; + } } else { if (psize == MMU_PAGE_512K) ptep = pte_offset_kernel(pmdp, va); else - ptep = hugepte_offset(*(hugepd_t *)pmdp, va, PGDIR_SHIFT); + ptep = (pte_t *)pmdp; } if (WARN_ON(!ptep)) return -ENOMEM; - /* The PTE should never be already present */ - if (new && WARN_ON(pte_present(*ptep) && pgprot_val(prot))) - return -EINVAL; - set_huge_pte_at(&init_mm, va, ptep, pte_mkhuge(pfn_pte(pa >> PAGE_SHIFT, prot)), 1UL << mmu_psize_to_shift(psize)); diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c index 9010973f036c..294775c793ab 100644 --- a/arch/powerpc/mm/pgtable.c +++ b/arch/powerpc/mm/pgtable.c @@ -297,11 +297,8 @@ int huge_ptep_set_access_flags(struct vm_area_struct *vma, } #if defined(CONFIG_PPC_8xx) -void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, - pte_t pte, unsigned long sz) +static void __set_huge_pte_at(pmd_t *pmd, pte_t *ptep, pte_basic_t val) { - pmd_t *pmd = pmd_off(mm, addr); - pte_basic_t val; pte_basic_t *entry = (pte_basic_t *)ptep; int num, i; @@ -311,15 +308,29 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, */ VM_WARN_ON(pte_hw_valid(*ptep) && !pte_protnone(*ptep)); - pte = set_pte_filter(pte, addr); - - val = pte_val(pte); - num = number_of_cells_per_pte(pmd, val, 1); for (i = 0; i < num; i++, entry++, val += SZ_4K) *entry = val; } + +void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, + pte_t pte, unsigned long sz) +{ + pmd_t *pmdp = pmd_off(mm, addr); + + pte = set_pte_filter(pte, addr); + + if (sz == SZ_8M) { /* Flag both PMD entries as 8M and fill both page tables */ + *pmdp = __pmd(pmd_val(*pmdp) | _PMD_PAGE_8M); + *(pmdp + 1) = __pmd(pmd_val(*(pmdp + 1)) | _PMD_PAGE_8M); + + __set_huge_pte_at(pmdp, pte_offset_kernel(pmdp, 0), pte_val(pte)); + __set_huge_pte_at(pmdp, pte_offset_kernel(pmdp + 1, 0), pte_val(pte) + SZ_4M); + } else { + __set_huge_pte_at(pmdp, ptep, pte_val(pte)); + } +} #endif #endif /* CONFIG_HUGETLB_PAGE */ diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c index cfd622ebf774..787b22206386 100644 --- a/arch/powerpc/mm/pgtable_32.c +++ b/arch/powerpc/mm/pgtable_32.c @@ -48,7 +48,7 @@ notrace void __init early_ioremap_init(void) early_ioremap_setup(); } -static void __init *early_alloc_pgtable(unsigned long size) +void __init *early_alloc_pgtable(unsigned long size) { void *ptr = memblock_alloc(size, size); diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype index 0c3c69ebf19f..fa4bb096b3ae 100644 --- a/arch/powerpc/platforms/Kconfig.cputype +++ b/arch/powerpc/platforms/Kconfig.cputype @@ -37,7 +37,6 @@ config PPC_85xx config PPC_8xx bool "Freescale 8xx" - select ARCH_HAS_HUGEPD if HUGETLB_PAGE select ARCH_SUPPORTS_HUGETLBFS select FSL_SOC select PPC_KUEP -- 2.44.0