Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753325AbaDPEdi (ORCPT ); Wed, 16 Apr 2014 00:33:38 -0400 Received: from mailout2.samsung.com ([203.254.224.25]:41827 "EHLO mailout2.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753131AbaDPEda (ORCPT ); Wed, 16 Apr 2014 00:33:30 -0400 X-AuditID: cbfee68d-b7fcd6d00000315b-0c-534e081826a8 From: Jungseok Lee To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, Catalin.Marinas@arm.com, Marc Zyngier , Christoffer Dall Cc: linux-kernel@vger.kernel.org, linux-samsung-soc , steve.capper@linaro.org, sungjinn.chung@samsung.com, Arnd Bergmann , kgene.kim@samsung.com, ilho215.lee@samsung.com Subject: [PATCH v2 6/7] arm64: mm: Implement 4 levels of translation tables Date: Wed, 16 Apr 2014 13:33:28 +0900 Message-id: <004601cf592d$037c1e60$0a745b20$@samsung.com> MIME-version: 1.0 Content-type: text/plain; charset=us-ascii Content-transfer-encoding: 7bit X-Mailer: Microsoft Outlook 14.0 Thread-index: Ac9ZK4lVtBsXehYdRCGfuscDDk6Eog== Content-language: ko X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrHIsWRmVeSWpSXmKPExsVy+t8zQ10JDr9gg/7HBhZ/Jx1jt3i/rIfR 4sXrf4wWR/8tZLToXXCVzeLjqePsFpseX2O1uLxrDpvFjPP7mCz+3vnHZrFi3jI2iw8zVjI6 8HismbeG0eP3r0mMHneu7WHzOL9pDbPH5iX1Hn1bVjF6fN4kF8AexWWTkpqTWZZapG+XwJWx du01xoL+/IqHDZeYGxhPRXUxcnJICJhIvDqwmwnCFpO4cG89WxcjF4eQwDJGiQWHf7LDFP38 vAMqMZ1R4vDxx8wQzh9GiTMfZzCCVLEJaEo8utvDDpIQEdjBKDF57SJWEIdZ4CGjxM+3+5lB qoQFvCVO3esEW8gioCqxc/JHVhCbV8BSYtLE38wQtqDEj8n3WEBsZgEtifU7jzNB2PISm9e8 ZYa4SUFix9nXQJs5gLbpSXQts4YoEZHY9+IdI8heCYFODomP6/ZB7RKQ+Db5EAtIvYSArMSm A1BjJCUOrrjBMoFRbBaSzbOQbJ6FZPMsJCsWMLKsYhRNLUguKE5KLzLUK07MLS7NS9dLzs/d xAiJ694djLcPWB9iTAZaP5FZSjQ5H5gW8kriDY3NjCxMTUyNjcwtzUgTVhLnTXqYFCQkkJ5Y kpqdmlqQWhRfVJqTWnyIkYmDU6qBceWNU695v/n+l51r0d3WejHzncIN64LsxMvNfSUS/wSs X68sfn911w72PUknX2k9rJs23cXIKHW2mtetoOYgK5mGstm2a9dG+H9O+rLfY33F59IVTtmP 1orWe29lelTDHTLvaVjz2cm8MyWK1I5dj+nwO3nq+ny3B14pWp36ka/OZic9E9dQV2Ipzkg0 1GIuKk4EAIs7cXoBAwAA X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFjrNKsWRmVeSWpSXmKPExsVy+t9jQV0JDr9ggw87tSz+TjrGbvF+WQ+j xYvX/xgtjv5byGjRu+Aqm8XHU8fZLTY9vsZqcXnXHDaLGef3MVn8vfOPzWLFvGVsFh9mrGR0 4PFYM28No8fvX5MYPe5c28PmcX7TGmaPzUvqPfq2rGL0+LxJLoA9qoHRJiM1MSW1SCE1Lzk/ JTMv3VbJOzjeOd7UzMBQ19DSwlxJIS8xN9VWycUnQNctMwfoUiWFssScUqBQQGJxsZK+HaYJ oSFuuhYwjRG6viFBcD1GBmggYR1jxtq11xgL+vMrHjZcYm5gPBXVxcjJISFgIvHz8w42CFtM 4sK99UA2F4eQwHRGicPHHzNDOH8YJc58nMEIUsUmoCnx6G4PO0hCRGAHo8TktYtYQRxmgYeM Ej/f7mcGqRIW8JY4da+TCcRmEVCV2Dn5IyuIzStgKTFp4m9mCFtQ4sfkeywgNrOAlsT6nceZ IGx5ic1r3jJD3KQgsePsa6DNHEDb9CS6lllDlIhI7HvxjnECo8AsJJNmIZk0C8mkWUhaFjCy rGIUTS1ILihOSs811CtOzC0uzUvXS87P3cQIThrPpHYwrmywOMQowMGoxMM7I8c3WIg1say4 MvcQowQHs5II75cvQCHelMTKqtSi/Pii0pzU4kOMyUCPTmSWEk3OBya0vJJ4Q2MTMyNLIzML IxNzc9KElcR5D7RaBwoJpCeWpGanphakFsFsYeLglGpg3LpHfL5t2ouHNzLKvrQsz4rhuJCy oM5UUkb7xv1595cq/zkd5sS1LYOh49LV/apHmJT0LHdVeJxTPMObkNKYPXvt1DXpgS66R1OZ 5qfvM57YxvFQ5CHzIzFLuW9Pk5ec4l3yj+nnxvZ/xpseWlzdacRv+/rA938HZOTD3Dxcr/jm Pv2wT5hxkRJLcUaioRZzUXEiALYg/Q5eAwAA DLP-Filter: Pass X-MTR: 20000000000000000@CPGS X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch implements 4 levels of translation tables since 3 levels of page tables with 4KB pages cannot support 40-bit physical address space described in [1] due to the following issue. It is a restriction that kernel logical memory map with 4KB + 3 levels (0xffffffc000000000-0xffffffffffffffff) cannot cover RAM region from 544GB to 1024GB in [1]. Specifically, ARM64 kernel fails to create mapping for this region in map_mem function since __phys_to_virt for this region reaches to address overflow. If SoC design follows the document, [1], over 32GB RAM would be placed from 544GB. Even 64GB system is supposed to use the region from 544GB to 576GB for only 32GB RAM. Naturally, it would reach to enable 4 levels of page tables to avoid hacking __virt_to_phys and __phys_to_virt. However, it is recommended 4 levels of page table should be only enabled if memory map is too sparse or there is about 512GB RAM. References ---------- [1]: Principles of ARM Memory Maps, White Paper, Issue C Signed-off-by: Jungseok Lee Reviewed-by: Sungjinn Chung --- arch/arm64/Kconfig | 7 +++++ arch/arm64/include/asm/memblock.h | 6 +++++ arch/arm64/include/asm/page.h | 4 ++- arch/arm64/include/asm/pgalloc.h | 20 +++++++++++++++ arch/arm64/include/asm/pgtable-hwdef.h | 6 +++-- arch/arm64/include/asm/pgtable.h | 44 ++++++++++++++++++++++++++++++-- arch/arm64/include/asm/tlb.h | 8 ++++++ arch/arm64/kernel/head.S | 40 ++++++++++++++++++++--------- arch/arm64/kernel/traps.c | 5 ++++ arch/arm64/mm/fault.c | 1 + arch/arm64/mm/mmu.c | 16 +++++++++--- 11 files changed, 136 insertions(+), 21 deletions(-) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 431acbc..7f5270b 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -184,12 +184,19 @@ config ARM64_3_LEVELS help This feature enables 3 levels of translation tables. +config ARM64_4_LEVELS + bool "4 level" + depends on ARM64_4K_PAGES + help + This feature enables 4 levels of translation tables. + endchoice config ARM64_VA_BITS int "Virtual address space size" range 39 39 if ARM64_4K_PAGES && ARM64_3_LEVELS range 42 42 if ARM64_64K_PAGES && ARM64_2_LEVELS + range 48 48 if ARM64_4K_PAGES && ARM64_4_LEVELS help This feature is determined by a combination of page size and level of translation tables. diff --git a/arch/arm64/include/asm/memblock.h b/arch/arm64/include/asm/memblock.h index 6afeed2..e4ac8bf 100644 --- a/arch/arm64/include/asm/memblock.h +++ b/arch/arm64/include/asm/memblock.h @@ -16,6 +16,12 @@ #ifndef __ASM_MEMBLOCK_H #define __ASM_MEMBLOCK_H +#ifndef CONFIG_ARM64_4_LEVELS +#define MEMBLOCK_INITIAL_LIMIT PGDIR_SIZE +#else +#define MEMBLOCK_INITIAL_LIMIT PUD_SIZE +#endif + extern void arm64_memblock_init(void); #endif diff --git a/arch/arm64/include/asm/page.h b/arch/arm64/include/asm/page.h index 268e53d..83b5289 100644 --- a/arch/arm64/include/asm/page.h +++ b/arch/arm64/include/asm/page.h @@ -35,8 +35,10 @@ #ifdef CONFIG_ARM64_2_LEVELS #include -#else +#elif defined(CONFIG_ARM64_3_LEVELS) #include +#else +#include #endif extern void __cpu_clear_user_page(void *p, unsigned long user); diff --git a/arch/arm64/include/asm/pgalloc.h b/arch/arm64/include/asm/pgalloc.h index 4829837..8d745fa 100644 --- a/arch/arm64/include/asm/pgalloc.h +++ b/arch/arm64/include/asm/pgalloc.h @@ -26,6 +26,26 @@ #define check_pgt_cache() do { } while (0) +#ifdef CONFIG_ARM64_4_LEVELS + +static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr) +{ + return (pud_t *)get_zeroed_page(GFP_KERNEL | __GFP_REPEAT); +} + +static inline void pud_free(struct mm_struct *mm, pud_t *pud) +{ + BUG_ON((unsigned long)pud & (PAGE_SIZE-1)); + free_page((unsigned long)pud); +} + +static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pud_t *pud) +{ + set_pgd(pgd, __pgd(__pa(pud) | PUD_TYPE_TABLE)); +} + +#endif /* CONFIG_ARM64_4_LEVELS */ + #ifndef CONFIG_ARM64_2_LEVELS static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr) diff --git a/arch/arm64/include/asm/pgtable-hwdef.h b/arch/arm64/include/asm/pgtable-hwdef.h index 9cd86c6..ba30053 100644 --- a/arch/arm64/include/asm/pgtable-hwdef.h +++ b/arch/arm64/include/asm/pgtable-hwdef.h @@ -18,8 +18,10 @@ #ifdef CONFIG_ARM64_2_LEVELS #include -#else +#elif defined(CONFIG_ARM64_3_LEVELS) #include +#else +#include #endif /* @@ -27,7 +29,7 @@ * * Level 1 descriptor (PUD). */ - +#define PUD_TYPE_TABLE (_AT(pudval_t, 3) << 0) #define PUD_TABLE_BIT (_AT(pgdval_t, 1) << 1) /* diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index a64ce5e..efc40d1 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -35,7 +35,11 @@ * VMALLOC and SPARSEMEM_VMEMMAP ranges. */ #define VMALLOC_START (UL(0xffffffffffffffff) << VA_BITS) +#ifndef CONFIG_ARM64_4_LEVELS #define VMALLOC_END (PAGE_OFFSET - UL(0x400000000) - SZ_64K) +#else +#define VMALLOC_END (PAGE_OFFSET - UL(0x40000000000) - SZ_64K) +#endif #define vmemmap ((struct page *)(VMALLOC_END + SZ_64K)) @@ -44,12 +48,16 @@ #ifndef __ASSEMBLY__ extern void __pte_error(const char *file, int line, unsigned long val); extern void __pmd_error(const char *file, int line, unsigned long val); +extern void __pud_error(const char *file, int line, unsigned long val); extern void __pgd_error(const char *file, int line, unsigned long val); #define pte_ERROR(pte) __pte_error(__FILE__, __LINE__, pte_val(pte)) #ifndef CONFIG_ARM64_2_LEVELS #define pmd_ERROR(pmd) __pmd_error(__FILE__, __LINE__, pmd_val(pmd)) #endif +#ifdef CONFIG_ARM64_4_LEVELS +#define pud_ERROR(pud) __pud_error(__FILE__, __LINE__, pud_val(pud)) +#endif #define pgd_ERROR(pgd) __pgd_error(__FILE__, __LINE__, pgd_val(pgd)) /* @@ -344,6 +352,30 @@ static inline pmd_t *pud_page_vaddr(pud_t pud) #endif /* CONFIG_ARM64_2_LEVELS */ +#ifdef CONFIG_ARM64_4_LEVELS + +#define pgd_none(pgd) (!pgd_val(pgd)) +#define pgd_bad(pgd) (!(pgd_val(pgd) & 2)) +#define pgd_present(pgd) (pgd_val(pgd)) + +static inline void set_pgd(pgd_t *pgdp, pgd_t pgd) +{ + *pgdp = pgd; + dsb(); +} + +static inline void pgd_clear(pgd_t *pgdp) +{ + set_pgd(pgdp, __pgd(0)); +} + +static inline pud_t *pgd_page_vaddr(pgd_t pgd) +{ + return __va(pgd_val(pgd) & PHYS_MASK & (s32)PAGE_MASK); +} + +#endif /* CONFIG_ARM64_4_LEVELS */ + /* to find an entry in a page-table-directory */ #define pgd_index(addr) (((addr) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1)) @@ -352,6 +384,14 @@ static inline pmd_t *pud_page_vaddr(pud_t pud) /* to find an entry in a kernel page-table-directory */ #define pgd_offset_k(addr) pgd_offset(&init_mm, addr) +#ifdef CONFIG_ARM64_4_LEVELS +#define pud_index(addr) (((addr) >> PUD_SHIFT) & (PTRS_PER_PUD - 1)) +static inline pud_t *pud_offset(pgd_t *pgd, unsigned long addr) +{ + return (pud_t *)pgd_page_vaddr(*pgd) + pud_index(addr); +} +#endif + /* Find an entry in the second-level page table.. */ #ifndef CONFIG_ARM64_2_LEVELS #define pmd_index(addr) (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1)) @@ -380,8 +420,8 @@ static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot) extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; extern pgd_t idmap_pg_dir[PTRS_PER_PGD]; -#define SWAPPER_DIR_SIZE (3 * PAGE_SIZE) -#define IDMAP_DIR_SIZE (2 * PAGE_SIZE) +#define SWAPPER_DIR_SIZE (4 * PAGE_SIZE) +#define IDMAP_DIR_SIZE (3 * PAGE_SIZE) /* * Encode and decode a swap entry: diff --git a/arch/arm64/include/asm/tlb.h b/arch/arm64/include/asm/tlb.h index df378b2..dedfb04 100644 --- a/arch/arm64/include/asm/tlb.h +++ b/arch/arm64/include/asm/tlb.h @@ -99,5 +99,13 @@ static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmdp, } #endif +#ifdef CONFIG_ARM64_4_LEVELS +static inline void __pud_free_tlb(struct mmu_gather *tlb, pmd_t *pudp, + unsigned long addr) +{ + tlb_add_flush(tlb, addr); + tlb_remove_page(tlb, virt_to_page(pudp)); +} +#endif #endif diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index 0fd5650..0b9d931 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -37,8 +37,8 @@ /* * swapper_pg_dir is the virtual address of the initial page table. We place - * the page tables 3 * PAGE_SIZE below KERNEL_RAM_VADDR. The idmap_pg_dir has - * 2 pages and is placed below swapper_pg_dir. + * the page tables 4 * PAGE_SIZE below KERNEL_RAM_VADDR. The idmap_pg_dir has + * 3 pages and is placed below swapper_pg_dir. */ #define KERNEL_RAM_VADDR (PAGE_OFFSET + TEXT_OFFSET) @@ -46,8 +46,8 @@ #error KERNEL_RAM_VADDR must start at 0xXXX80000 #endif -#define SWAPPER_DIR_SIZE (3 * PAGE_SIZE) -#define IDMAP_DIR_SIZE (2 * PAGE_SIZE) +#define SWAPPER_DIR_SIZE (4 * PAGE_SIZE) +#define IDMAP_DIR_SIZE (3 * PAGE_SIZE) .globl swapper_pg_dir .equ swapper_pg_dir, KERNEL_RAM_VADDR - SWAPPER_DIR_SIZE @@ -371,16 +371,29 @@ ENDPROC(__calc_phys_offset) /* * Macro to populate the PGD for the corresponding block entry in the next - * level (tbl) for the given virtual address. + * levels (tbl1 and tbl2) for the given virtual address. * - * Preserves: pgd, tbl, virt + * Preserves: pgd, tbl1, tbl2, virt * Corrupts: tmp1, tmp2 */ - .macro create_pgd_entry, pgd, tbl, virt, tmp1, tmp2 + .macro create_pgd_entry, pgd, tbl1, tbl2, virt, tmp1, tmp2 lsr \tmp1, \virt, #PGDIR_SHIFT and \tmp1, \tmp1, #PTRS_PER_PGD - 1 // PGD index - orr \tmp2, \tbl, #3 // PGD entry table type + orr \tmp2, \tbl1, #3 // PGD entry table type str \tmp2, [\pgd, \tmp1, lsl #3] +#ifdef CONFIG_ARM64_4_LEVELS + ldr \tbl2, =FIXADDR_TOP + cmp \tbl2, \virt + add \tbl2, \tbl1, #PAGE_SIZE + b.ne 1f + add \tbl2, \tbl2, #PAGE_SIZE +1: + lsr \tmp1, \virt, #PUD_SHIFT + and \tmp1, \tmp1, #PTRS_PER_PUD - 1 // PUD index + orr \tmp2, \tbl2, #3 // PUD entry table type + str \tmp2, [\tbl1, \tmp1, lsl #3] + mov \tbl1, \tbl2 +#endif .endm /* @@ -444,7 +457,7 @@ __create_page_tables: add x0, x25, #PAGE_SIZE // section table address ldr x3, =KERNEL_START add x3, x3, x28 // __pa(KERNEL_START) - create_pgd_entry x25, x0, x3, x5, x6 + create_pgd_entry x25, x0, x1, x3, x5, x6 ldr x6, =KERNEL_END mov x5, x3 // __pa(KERNEL_START) add x6, x6, x28 // __pa(KERNEL_END) @@ -455,7 +468,7 @@ __create_page_tables: */ add x0, x26, #PAGE_SIZE // section table address mov x5, #PAGE_OFFSET - create_pgd_entry x26, x0, x5, x3, x6 + create_pgd_entry x26, x0, x1, x5, x3, x6 ldr x6, =KERNEL_END mov x3, x24 // phys offset create_block_map x0, x7, x3, x5, x6 @@ -480,8 +493,11 @@ __create_page_tables: * Create the pgd entry for the fixed mappings. */ ldr x5, =FIXADDR_TOP // Fixed mapping virtual address - add x0, x26, #2 * PAGE_SIZE // section table address - create_pgd_entry x26, x0, x5, x6, x7 + add x0, x26, #PAGE_SIZE +#ifndef CONFIG_ARM64_4_LEVELS + add x0, x26, #PAGE_SIZE +#endif + create_pgd_entry x26, x0, x1, x5, x6, x7 /* * Since the page tables have been populated with non-cacheable diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c index 0484e81..16d5ee5 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -336,6 +336,11 @@ void __pmd_error(const char *file, int line, unsigned long val) pr_crit("%s:%d: bad pmd %016lx.\n", file, line, val); } +void __pud_error(const char *file, int line, unsigned long val) +{ + pr_crit("%s:%d: bad pud %016lx.\n", file, line, val); +} + void __pgd_error(const char *file, int line, unsigned long val) { pr_crit("%s:%d: bad pgd %016lx.\n", file, line, val); diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index c23751b..ed4a343 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -61,6 +61,7 @@ void show_pte(struct mm_struct *mm, unsigned long addr) break; pud = pud_offset(pgd, addr); + printk(", *pud=%016llx", pud_val(*pud)); if (pud_none(*pud) || pud_bad(*pud)) break; diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 6b7e895..4d29332 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -32,6 +32,7 @@ #include #include #include +#include #include #include "mm.h" @@ -222,9 +223,15 @@ static void __init alloc_init_pmd(pud_t *pud, unsigned long addr, static void __init alloc_init_pud(pgd_t *pgd, unsigned long addr, unsigned long end, unsigned long phys) { - pud_t *pud = pud_offset(pgd, addr); + pud_t *pud; unsigned long next; + if (pgd_none(*pgd) || pgd_bad(*pgd)) { + pud = early_alloc(PTRS_PER_PUD * sizeof(pud_t)); + pgd_populate(&init_mm, pgd, pud); + } + + pud = pud_offset(pgd, addr); do { next = pud_addr_end(addr, end); alloc_init_pmd(pud, addr, next, phys); @@ -271,10 +278,11 @@ static void __init map_mem(void) * memory addressable from the initial direct kernel mapping. * * The initial direct kernel mapping, located at swapper_pg_dir, - * gives us PGDIR_SIZE memory starting from PHYS_OFFSET (which must be - * aligned to 2MB as per Documentation/arm64/booting.txt). + * gives us PGDIR_SIZE (2 and 3 levels) or PUD_SIZE (4 levels) memory + * starting from PHYS_OFFSET (which must be aligned to 2MB as per + * Documentation/arm64/booting.txt). */ - limit = PHYS_OFFSET + PGDIR_SIZE; + limit = PHYS_OFFSET + MEMBLOCK_INITIAL_LIMIT; memblock_set_current_limit(limit); /* map all the memory banks */ -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/