From: Mike Rapoport <rppt@xxxxxxxxxxxxx> Subject: arm: add support for folded p4d page tables Implement primitives necessary for the 4th level folding, add walks of p4d level where appropriate, and remove __ARCH_USE_5LEVEL_HACK. [rppt@xxxxxxxxxxxxx: fix kexec] Link: http://lkml.kernel.org/r/20200508174232.GA759899@xxxxxxxxxxxxx Link: http://lkml.kernel.org/r/20200414153455.21744-3-rppt@xxxxxxxxxx Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxx> Tested-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> Cc: Arnd Bergmann <arnd@xxxxxxxx> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: Brian Cain <bcain@xxxxxxxxxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: Christophe Leroy <christophe.leroy@xxxxxx> Cc: Fenghua Yu <fenghua.yu@xxxxxxxxx> Cc: Geert Uytterhoeven <geert+renesas@xxxxxxxxx> Cc: Guan Xuetao <gxt@xxxxxxxxxx> Cc: James Morse <james.morse@xxxxxxx> Cc: Jonas Bonn <jonas@xxxxxxxxxxxx> Cc: Julien Thierry <julien.thierry.kdev@xxxxxxxxx> Cc: Ley Foon Tan <ley.foon.tan@xxxxxxxxx> Cc: Marc Zyngier <maz@xxxxxxxxxx> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Rich Felker <dalias@xxxxxxxx> Cc: Russell King <linux@xxxxxxxxxxxxxxx> Cc: Stafford Horne <shorne@xxxxxxxxx> Cc: Stefan Kristiansson <stefan.kristiansson@xxxxxxxxxxxxx> Cc: Suzuki K Poulose <suzuki.poulose@xxxxxxx> Cc: Tony Luck <tony.luck@xxxxxxxxx> Cc: Will Deacon <will@xxxxxxxxxx> Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/arm/include/asm/pgtable.h | 1 arch/arm/lib/uaccess_with_memcpy.c | 7 ++++ arch/arm/mach-sa1100/assabet.c | 2 - arch/arm/mm/dump.c | 29 +++++++++++++++---- arch/arm/mm/fault-armv.c | 7 ++++ arch/arm/mm/fault.c | 22 +++++++++----- arch/arm/mm/idmap.c | 3 +- arch/arm/mm/init.c | 2 - arch/arm/mm/ioremap.c | 12 ++++++-- arch/arm/mm/mm.h | 2 - arch/arm/mm/mmu.c | 35 +++++++++++++++++++---- arch/arm/mm/pgd.c | 40 ++++++++++++++++++++++----- 12 files changed, 125 insertions(+), 37 deletions(-) --- a/arch/arm/include/asm/pgtable.h~arm-add-support-for-folded-p4d-page-tables +++ a/arch/arm/include/asm/pgtable.h @@ -17,7 +17,6 @@ #else -#define __ARCH_USE_5LEVEL_HACK #include <asm-generic/pgtable-nopud.h> #include <asm/memory.h> #include <asm/pgtable-hwdef.h> --- a/arch/arm/lib/uaccess_with_memcpy.c~arm-add-support-for-folded-p4d-page-tables +++ a/arch/arm/lib/uaccess_with_memcpy.c @@ -24,6 +24,7 @@ pin_page_for_write(const void __user *_a { unsigned long addr = (unsigned long)_addr; pgd_t *pgd; + p4d_t *p4d; pmd_t *pmd; pte_t *pte; pud_t *pud; @@ -33,7 +34,11 @@ pin_page_for_write(const void __user *_a if (unlikely(pgd_none(*pgd) || pgd_bad(*pgd))) return 0; - pud = pud_offset(pgd, addr); + p4d = p4d_offset(pgd, addr); + if (unlikely(p4d_none(*p4d) || p4d_bad(*p4d))) + return 0; + + pud = pud_offset(p4d, addr); if (unlikely(pud_none(*pud) || pud_bad(*pud))) return 0; --- a/arch/arm/mach-sa1100/assabet.c~arm-add-support-for-folded-p4d-page-tables +++ a/arch/arm/mach-sa1100/assabet.c @@ -633,7 +633,7 @@ static void __init map_sa1100_gpio_regs( int prot = PMD_TYPE_SECT | PMD_SECT_AP_WRITE | PMD_DOMAIN(DOMAIN_IO); pmd_t *pmd; - pmd = pmd_offset(pud_offset(pgd_offset_k(virt), virt), virt); + pmd = pmd_offset(pud_offset(p4d_offset(pgd_offset_k(virt), virt), virt), virt); *pmd = __pmd(phys | prot); flush_pmd_entry(pmd); } --- a/arch/arm/mm/dump.c~arm-add-support-for-folded-p4d-page-tables +++ a/arch/arm/mm/dump.c @@ -207,6 +207,7 @@ struct pg_level { static struct pg_level pg_level[] = { { }, { /* pgd */ + }, { /* p4d */ }, { /* pud */ }, { /* pmd */ .bits = section_bits, @@ -308,7 +309,7 @@ static void walk_pte(struct pg_state *st for (i = 0; i < PTRS_PER_PTE; i++, pte++) { addr = start + i * PAGE_SIZE; - note_page(st, addr, 4, pte_val(*pte), domain); + note_page(st, addr, 5, pte_val(*pte), domain); } } @@ -350,14 +351,14 @@ static void walk_pmd(struct pg_state *st addr += SECTION_SIZE; pmd++; domain = get_domain_name(pmd); - note_page(st, addr, 3, pmd_val(*pmd), domain); + note_page(st, addr, 4, pmd_val(*pmd), domain); } } } -static void walk_pud(struct pg_state *st, pgd_t *pgd, unsigned long start) +static void walk_pud(struct pg_state *st, p4d_t *p4d, unsigned long start) { - pud_t *pud = pud_offset(pgd, 0); + pud_t *pud = pud_offset(p4d, 0); unsigned long addr; unsigned i; @@ -366,7 +367,23 @@ static void walk_pud(struct pg_state *st if (!pud_none(*pud)) { walk_pmd(st, pud, addr); } else { - note_page(st, addr, 2, pud_val(*pud), NULL); + note_page(st, addr, 3, pud_val(*pud), NULL); + } + } +} + +static void walk_p4d(struct pg_state *st, pgd_t *pgd, unsigned long start) +{ + p4d_t *p4d = p4d_offset(pgd, 0); + unsigned long addr; + unsigned i; + + for (i = 0; i < PTRS_PER_P4D; i++, p4d++) { + addr = start + i * P4D_SIZE; + if (!p4d_none(*p4d)) { + walk_pud(st, p4d, addr); + } else { + note_page(st, addr, 2, p4d_val(*p4d), NULL); } } } @@ -381,7 +398,7 @@ static void walk_pgd(struct pg_state *st for (i = 0; i < PTRS_PER_PGD; i++, pgd++) { addr = start + i * PGDIR_SIZE; if (!pgd_none(*pgd)) { - walk_pud(st, pgd, addr); + walk_p4d(st, pgd, addr); } else { note_page(st, addr, 1, pgd_val(*pgd), NULL); } --- a/arch/arm/mm/fault-armv.c~arm-add-support-for-folded-p4d-page-tables +++ a/arch/arm/mm/fault-armv.c @@ -91,6 +91,7 @@ static int adjust_pte(struct vm_area_str { spinlock_t *ptl; pgd_t *pgd; + p4d_t *p4d; pud_t *pud; pmd_t *pmd; pte_t *pte; @@ -100,7 +101,11 @@ static int adjust_pte(struct vm_area_str if (pgd_none_or_clear_bad(pgd)) return 0; - pud = pud_offset(pgd, address); + p4d = p4d_offset(pgd, address); + if (p4d_none_or_clear_bad(p4d)) + return 0; + + pud = pud_offset(p4d, address); if (pud_none_or_clear_bad(pud)) return 0; --- a/arch/arm/mm/fault.c~arm-add-support-for-folded-p4d-page-tables +++ a/arch/arm/mm/fault.c @@ -43,19 +43,21 @@ void show_pte(const char *lvl, struct mm printk("%s[%08lx] *pgd=%08llx", lvl, addr, (long long)pgd_val(*pgd)); do { + p4d_t *p4d; pud_t *pud; pmd_t *pmd; pte_t *pte; - if (pgd_none(*pgd)) + p4d = p4d_offset(pgd, addr); + if (p4d_none(*p4d)) break; - if (pgd_bad(*pgd)) { + if (p4d_bad(*p4d)) { pr_cont("(bad)"); break; } - pud = pud_offset(pgd, addr); + pud = pud_offset(p4d, addr); if (PTRS_PER_PUD != 1) pr_cont(", *pud=%08llx", (long long)pud_val(*pud)); @@ -405,6 +407,7 @@ do_translation_fault(unsigned long addr, { unsigned int index; pgd_t *pgd, *pgd_k; + p4d_t *p4d, *p4d_k; pud_t *pud, *pud_k; pmd_t *pmd, *pmd_k; @@ -419,13 +422,16 @@ do_translation_fault(unsigned long addr, pgd = cpu_get_pgd() + index; pgd_k = init_mm.pgd + index; - if (pgd_none(*pgd_k)) + p4d = p4d_offset(pgd, addr); + p4d_k = p4d_offset(pgd_k, addr); + + if (p4d_none(*p4d_k)) goto bad_area; - if (!pgd_present(*pgd)) - set_pgd(pgd, *pgd_k); + if (!p4d_present(*p4d)) + set_p4d(p4d, *p4d_k); - pud = pud_offset(pgd, addr); - pud_k = pud_offset(pgd_k, addr); + pud = pud_offset(p4d, addr); + pud_k = pud_offset(p4d_k, addr); if (pud_none(*pud_k)) goto bad_area; --- a/arch/arm/mm/idmap.c~arm-add-support-for-folded-p4d-page-tables +++ a/arch/arm/mm/idmap.c @@ -68,7 +68,8 @@ static void idmap_add_pmd(pud_t *pud, un static void idmap_add_pud(pgd_t *pgd, unsigned long addr, unsigned long end, unsigned long prot) { - pud_t *pud = pud_offset(pgd, addr); + p4d_t *p4d = p4d_offset(pgd, addr); + pud_t *pud = pud_offset(p4d, addr); unsigned long next; do { --- a/arch/arm/mm/init.c~arm-add-support-for-folded-p4d-page-tables +++ a/arch/arm/mm/init.c @@ -519,7 +519,7 @@ static inline void section_update(unsign { pmd_t *pmd; - pmd = pmd_offset(pud_offset(pgd_offset(mm, addr), addr), addr); + pmd = pmd_offset(pud_offset(p4d_offset(pgd_offset(mm, addr), addr), addr), addr); #ifdef CONFIG_ARM_LPAE pmd[0] = __pmd((pmd_val(pmd[0]) & mask) | prot); --- a/arch/arm/mm/ioremap.c~arm-add-support-for-folded-p4d-page-tables +++ a/arch/arm/mm/ioremap.c @@ -142,12 +142,14 @@ static void unmap_area_sections(unsigned { unsigned long addr = virt, end = virt + (size & ~(SZ_1M - 1)); pgd_t *pgd; + p4d_t *p4d; pud_t *pud; pmd_t *pmdp; flush_cache_vunmap(addr, end); pgd = pgd_offset_k(addr); - pud = pud_offset(pgd, addr); + p4d = p4d_offset(pgd, addr); + pud = pud_offset(p4d, addr); pmdp = pmd_offset(pud, addr); do { pmd_t pmd = *pmdp; @@ -190,6 +192,7 @@ remap_area_sections(unsigned long virt, { unsigned long addr = virt, end = virt + size; pgd_t *pgd; + p4d_t *p4d; pud_t *pud; pmd_t *pmd; @@ -200,7 +203,8 @@ remap_area_sections(unsigned long virt, unmap_area_sections(virt, size); pgd = pgd_offset_k(addr); - pud = pud_offset(pgd, addr); + p4d = p4d_offset(pgd, addr); + pud = pud_offset(p4d, addr); pmd = pmd_offset(pud, addr); do { pmd[0] = __pmd(__pfn_to_phys(pfn) | type->prot_sect); @@ -222,6 +226,7 @@ remap_area_supersections(unsigned long v { unsigned long addr = virt, end = virt + size; pgd_t *pgd; + p4d_t *p4d; pud_t *pud; pmd_t *pmd; @@ -232,7 +237,8 @@ remap_area_supersections(unsigned long v unmap_area_sections(virt, size); pgd = pgd_offset_k(virt); - pud = pud_offset(pgd, addr); + p4d = p4d_offset(pgd, addr); + pud = pud_offset(p4d, addr); pmd = pmd_offset(pud, addr); do { unsigned long super_pmd_val, i; --- a/arch/arm/mm/mm.h~arm-add-support-for-folded-p4d-page-tables +++ a/arch/arm/mm/mm.h @@ -38,7 +38,7 @@ static inline pte_t get_top_pte(unsigned static inline pmd_t *pmd_off_k(unsigned long virt) { - return pmd_offset(pud_offset(pgd_offset_k(virt), virt), virt); + return pmd_offset(pud_offset(p4d_offset(pgd_offset_k(virt), virt), virt), virt); } struct mem_type { --- a/arch/arm/mm/mmu.c~arm-add-support-for-folded-p4d-page-tables +++ a/arch/arm/mm/mmu.c @@ -357,7 +357,8 @@ static pte_t *pte_offset_late_fixmap(pmd static inline pmd_t * __init fixmap_pmd(unsigned long addr) { pgd_t *pgd = pgd_offset_k(addr); - pud_t *pud = pud_offset(pgd, addr); + p4d_t *p4d = p4d_offset(pgd, addr); + pud_t *pud = pud_offset(p4d, addr); pmd_t *pmd = pmd_offset(pud, addr); return pmd; @@ -801,12 +802,12 @@ static void __init alloc_init_pmd(pud_t } while (pmd++, addr = next, addr != end); } -static void __init alloc_init_pud(pgd_t *pgd, unsigned long addr, +static void __init alloc_init_pud(p4d_t *p4d, unsigned long addr, unsigned long end, phys_addr_t phys, const struct mem_type *type, void *(*alloc)(unsigned long sz), bool ng) { - pud_t *pud = pud_offset(pgd, addr); + pud_t *pud = pud_offset(p4d, addr); unsigned long next; do { @@ -816,6 +817,21 @@ static void __init alloc_init_pud(pgd_t } while (pud++, addr = next, addr != end); } +static void __init alloc_init_p4d(pgd_t *pgd, unsigned long addr, + unsigned long end, phys_addr_t phys, + const struct mem_type *type, + void *(*alloc)(unsigned long sz), bool ng) +{ + p4d_t *p4d = p4d_offset(pgd, addr); + unsigned long next; + + do { + next = p4d_addr_end(addr, end); + alloc_init_pud(p4d, addr, next, phys, type, alloc, ng); + phys += next - addr; + } while (p4d++, addr = next, addr != end); +} + #ifndef CONFIG_ARM_LPAE static void __init create_36bit_mapping(struct mm_struct *mm, struct map_desc *md, @@ -863,7 +879,8 @@ static void __init create_36bit_mapping( pgd = pgd_offset(mm, addr); end = addr + length; do { - pud_t *pud = pud_offset(pgd, addr); + p4d_t *p4d = p4d_offset(pgd, addr); + pud_t *pud = pud_offset(p4d, addr); pmd_t *pmd = pmd_offset(pud, addr); int i; @@ -914,7 +931,7 @@ static void __init __create_mapping(stru do { unsigned long next = pgd_addr_end(addr, end); - alloc_init_pud(pgd, addr, next, phys, type, alloc, ng); + alloc_init_p4d(pgd, addr, next, phys, type, alloc, ng); phys += next - addr; addr = next; @@ -950,7 +967,13 @@ void __init create_mapping_late(struct m bool ng) { #ifdef CONFIG_ARM_LPAE - pud_t *pud = pud_alloc(mm, pgd_offset(mm, md->virtual), md->virtual); + p4d_t *p4d; + pud_t *pud; + + p4d = p4d_alloc(mm, pgd_offset(mm, md->virtual), md->virtual); + if (!WARN_ON(!p4d)) + return; + pud = pud_alloc(mm, p4d, md->virtual); if (WARN_ON(!pud)) return; pmd_alloc(mm, pud, 0); --- a/arch/arm/mm/pgd.c~arm-add-support-for-folded-p4d-page-tables +++ a/arch/arm/mm/pgd.c @@ -30,6 +30,7 @@ pgd_t *pgd_alloc(struct mm_struct *mm) { pgd_t *new_pgd, *init_pgd; + p4d_t *new_p4d, *init_p4d; pud_t *new_pud, *init_pud; pmd_t *new_pmd, *init_pmd; pte_t *new_pte, *init_pte; @@ -53,8 +54,12 @@ pgd_t *pgd_alloc(struct mm_struct *mm) /* * Allocate PMD table for modules and pkmap mappings. */ - new_pud = pud_alloc(mm, new_pgd + pgd_index(MODULES_VADDR), + new_p4d = p4d_alloc(mm, new_pgd + pgd_index(MODULES_VADDR), MODULES_VADDR); + if (!new_p4d) + goto no_p4d; + + new_pud = pud_alloc(mm, new_p4d, MODULES_VADDR); if (!new_pud) goto no_pud; @@ -69,7 +74,11 @@ pgd_t *pgd_alloc(struct mm_struct *mm) * contains the machine vectors. The vectors are always high * with LPAE. */ - new_pud = pud_alloc(mm, new_pgd, 0); + new_p4d = p4d_alloc(mm, new_pgd, 0); + if (!new_p4d) + goto no_p4d; + + new_pud = pud_alloc(mm, new_p4d, 0); if (!new_pud) goto no_pud; @@ -91,7 +100,8 @@ pgd_t *pgd_alloc(struct mm_struct *mm) pmd_val(*new_pmd) |= PMD_DOMAIN(DOMAIN_VECTORS); #endif - init_pud = pud_offset(init_pgd, 0); + init_p4d = p4d_offset(init_pgd, 0); + init_pud = pud_offset(init_p4d, 0); init_pmd = pmd_offset(init_pud, 0); init_pte = pte_offset_map(init_pmd, 0); set_pte_ext(new_pte + 0, init_pte[0], 0); @@ -108,6 +118,8 @@ no_pte: no_pmd: pud_free(mm, new_pud); no_pud: + p4d_free(mm, new_p4d); +no_p4d: __pgd_free(new_pgd); no_pgd: return NULL; @@ -116,6 +128,7 @@ no_pgd: void pgd_free(struct mm_struct *mm, pgd_t *pgd_base) { pgd_t *pgd; + p4d_t *p4d; pud_t *pud; pmd_t *pmd; pgtable_t pte; @@ -127,7 +140,11 @@ void pgd_free(struct mm_struct *mm, pgd_ if (pgd_none_or_clear_bad(pgd)) goto no_pgd; - pud = pud_offset(pgd, 0); + p4d = p4d_offset(pgd, 0); + if (p4d_none_or_clear_bad(p4d)) + goto no_p4d; + + pud = pud_offset(p4d, 0); if (pud_none_or_clear_bad(pud)) goto no_pud; @@ -144,8 +161,11 @@ no_pmd: pmd_free(mm, pmd); mm_dec_nr_pmds(mm); no_pud: - pgd_clear(pgd); + p4d_clear(p4d); pud_free(mm, pud); +no_p4d: + pgd_clear(pgd); + p4d_free(mm, p4d); no_pgd: #ifdef CONFIG_ARM_LPAE /* @@ -156,15 +176,21 @@ no_pgd: continue; if (pgd_val(*pgd) & L_PGD_SWAPPER) continue; - pud = pud_offset(pgd, 0); + p4d = p4d_offset(pgd, 0); + if (p4d_none_or_clear_bad(p4d)) + continue; + pud = pud_offset(p4d, 0); if (pud_none_or_clear_bad(pud)) continue; pmd = pmd_offset(pud, 0); pud_clear(pud); pmd_free(mm, pmd); mm_dec_nr_pmds(mm); - pgd_clear(pgd); + p4d_clear(p4d); pud_free(mm, pud); + mm_dec_nr_puds(mm); + pgd_clear(pgd); + p4d_free(mm, p4d); } #endif __pgd_free(pgd_base); _
