From fd062c847a8cea2821347d7e18165dfa658f7dce Mon Sep 17 00:00:00 2001 From: David Daney Date: Wed, 27 May 2009 17:47:44 -0700 Subject: [PATCH] MIPS: TLB support for hugetlbfs. The TLB handlers need to check for huge pages and give them special handling. Huge pages consist of two contiguous sub-pages of physical memory. * Loading entrylo0 and entrylo1 need to be handled specially. * The page mask must be set for huge pages and then restored after writing the TLB entries. * The PTE for huge pages resides in the PMD, we halt traversal of the tables there. Signed-off-by: David Daney Signed-off-by: Ralf Baechle --- arch/mips/mm/tlb-r4k.c | 43 ++++++++--- arch/mips/mm/tlbex.c | 165 ++++++++++++++++++++++++++++++++++++++++- 2 files changed, 196 insertions(+), 12 deletions(-) diff --git a/arch/mips/mm/tlb-r4k.c b/arch/mips/mm/tlb-r4k.c index 892be426787c..f60fe513eb60 100644 --- a/arch/mips/mm/tlb-r4k.c +++ b/arch/mips/mm/tlb-r4k.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include @@ -295,21 +296,41 @@ void __update_tlb(struct vm_area_struct * vma, unsigned long address, pte_t pte) pudp = pud_offset(pgdp, address); pmdp = pmd_offset(pudp, address); idx = read_c0_index(); - ptep = pte_offset_map(pmdp, address); +#ifdef CONFIG_HUGETLB_PAGE + /* this could be a huge page */ + if (pmd_huge(*pmdp)) { + unsigned long lo; + write_c0_pagemask(PM_HUGE_MASK); + ptep = (pte_t *)pmdp; + lo = pte_val(*ptep) >> 6; + write_c0_entrylo0(lo); + write_c0_entrylo1(lo + (HPAGE_SIZE >> 7)); + + mtc0_tlbw_hazard(); + if (idx < 0) + tlb_write_random(); + else + tlb_write_indexed(); + write_c0_pagemask(PM_DEFAULT_MASK); + } else +#endif + { + ptep = pte_offset_map(pmdp, address); #if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32) - write_c0_entrylo0(ptep->pte_high); - ptep++; - write_c0_entrylo1(ptep->pte_high); + write_c0_entrylo0(ptep->pte_high); + ptep++; + write_c0_entrylo1(ptep->pte_high); #else - write_c0_entrylo0(pte_val(*ptep++) >> 6); - write_c0_entrylo1(pte_val(*ptep) >> 6); + write_c0_entrylo0(pte_val(*ptep++) >> 6); + write_c0_entrylo1(pte_val(*ptep) >> 6); #endif - mtc0_tlbw_hazard(); - if (idx < 0) - tlb_write_random(); - else - tlb_write_indexed(); + mtc0_tlbw_hazard(); + if (idx < 0) + tlb_write_random(); + else + tlb_write_indexed(); + } tlbw_use_hazard(); FLUSH_ITLB_VM(vma); EXIT_CRITICAL(flags); diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c index 62fbd0d89aeb..8f606ead826e 100644 --- a/arch/mips/mm/tlbex.c +++ b/arch/mips/mm/tlbex.c @@ -8,6 +8,7 @@ * Copyright (C) 2004, 2005, 2006, 2008 Thiemo Seufer * Copyright (C) 2005, 2007, 2008, 2009 Maciej W. Rozycki * Copyright (C) 2006 Ralf Baechle (ralf@linux-mips.org) + * Copyright (C) 2008, 2009 Cavium Networks, Inc. * * ... and the days got worse and worse and now you see * I've gone completly out of my mind. @@ -83,6 +84,9 @@ enum label_id { label_nopage_tlbm, label_smp_pgtable_change, label_r3000_write_probe_fail, +#ifdef CONFIG_HUGETLB_PAGE + label_tlb_huge_update, +#endif }; UASM_L_LA(_second_part) @@ -99,6 +103,9 @@ UASM_L_LA(_nopage_tlbs) UASM_L_LA(_nopage_tlbm) UASM_L_LA(_smp_pgtable_change) UASM_L_LA(_r3000_write_probe_fail) +#ifdef CONFIG_HUGETLB_PAGE +UASM_L_LA(_tlb_huge_update) +#endif /* * For debug purposes. @@ -126,6 +133,7 @@ static inline void dump_handler(const u32 *handler, int count) #define C0_TCBIND 2, 2 #define C0_ENTRYLO1 3, 0 #define C0_CONTEXT 4, 0 +#define C0_PAGEMASK 5, 0 #define C0_BADVADDR 8, 0 #define C0_ENTRYHI 10, 0 #define C0_EPC 14, 0 @@ -383,6 +391,98 @@ static void __cpuinit build_tlb_write_entry(u32 **p, struct uasm_label **l, } } +#ifdef CONFIG_HUGETLB_PAGE +static __cpuinit void build_huge_tlb_write_entry(u32 **p, + struct uasm_label **l, + struct uasm_reloc **r, + unsigned int tmp, + enum tlb_write_entry wmode) +{ + /* Set huge page tlb entry size */ + uasm_i_lui(p, tmp, PM_HUGE_MASK >> 16); + uasm_i_ori(p, tmp, tmp, PM_HUGE_MASK & 0xffff); + uasm_i_mtc0(p, tmp, C0_PAGEMASK); + + build_tlb_write_entry(p, l, r, wmode); + + /* Reset default page size */ + if (PM_DEFAULT_MASK >> 16) { + uasm_i_lui(p, tmp, PM_DEFAULT_MASK >> 16); + uasm_i_ori(p, tmp, tmp, PM_DEFAULT_MASK & 0xffff); + uasm_il_b(p, r, label_leave); + uasm_i_mtc0(p, tmp, C0_PAGEMASK); + } else if (PM_DEFAULT_MASK) { + uasm_i_ori(p, tmp, 0, PM_DEFAULT_MASK); + uasm_il_b(p, r, label_leave); + uasm_i_mtc0(p, tmp, C0_PAGEMASK); + } else { + uasm_il_b(p, r, label_leave); + uasm_i_mtc0(p, 0, C0_PAGEMASK); + } +} + +/* + * Check if Huge PTE is present, if so then jump to LABEL. + */ +static void __cpuinit +build_is_huge_pte(u32 **p, struct uasm_reloc **r, unsigned int tmp, + unsigned int pmd, int lid) +{ + UASM_i_LW(p, tmp, 0, pmd); + uasm_i_andi(p, tmp, tmp, _PAGE_HUGE); + uasm_il_bnez(p, r, tmp, lid); +} + +static __cpuinit void build_huge_update_entries(u32 **p, + unsigned int pte, + unsigned int tmp) +{ + int small_sequence; + + /* + * A huge PTE describes an area the size of the + * configured huge page size. This is twice the + * of the large TLB entry size we intend to use. + * A TLB entry half the size of the configured + * huge page size is configured into entrylo0 + * and entrylo1 to cover the contiguous huge PTE + * address space. + */ + small_sequence = (HPAGE_SIZE >> 7) < 0x10000; + + /* We can clobber tmp. It isn't used after this.*/ + if (!small_sequence) + uasm_i_lui(p, tmp, HPAGE_SIZE >> (7 + 16)); + + UASM_i_SRL(p, pte, pte, 6); /* convert to entrylo */ + uasm_i_mtc0(p, pte, C0_ENTRYLO0); /* load it */ + /* convert to entrylo1 */ + if (small_sequence) + UASM_i_ADDIU(p, pte, pte, HPAGE_SIZE >> 7); + else + UASM_i_ADDU(p, pte, pte, tmp); + + uasm_i_mtc0(p, pte, C0_ENTRYLO1); /* load it */ +} + +static __cpuinit void build_huge_handler_tail(u32 **p, + struct uasm_reloc **r, + struct uasm_label **l, + unsigned int pte, + unsigned int ptr) +{ +#ifdef CONFIG_SMP + UASM_i_SC(p, pte, 0, ptr); + uasm_il_beqz(p, r, pte, label_tlb_huge_update); + UASM_i_LW(p, pte, 0, ptr); /* Needed because SC killed our PTE */ +#else + UASM_i_SW(p, pte, 0, ptr); +#endif + build_huge_update_entries(p, pte, ptr); + build_huge_tlb_write_entry(p, l, r, pte, tlb_indexed); +} +#endif /* CONFIG_HUGETLB_PAGE */ + #ifdef CONFIG_64BIT /* * TMP and PTR are scratch. @@ -689,12 +789,23 @@ static void __cpuinit build_r4000_tlb_refill_handler(void) build_get_pgde32(&p, K0, K1); /* get pgd in K1 */ #endif +#ifdef CONFIG_HUGETLB_PAGE + build_is_huge_pte(&p, &r, K0, K1, label_tlb_huge_update); +#endif + build_get_ptep(&p, K0, K1); build_update_entries(&p, K0, K1); build_tlb_write_entry(&p, &l, &r, tlb_random); uasm_l_leave(&l, p); uasm_i_eret(&p); /* return from trap */ +#ifdef CONFIG_HUGETLB_PAGE + uasm_l_tlb_huge_update(&l, p); + UASM_i_LW(&p, K0, 0, K1); + build_huge_update_entries(&p, K0, K1); + build_huge_tlb_write_entry(&p, &l, &r, K0, tlb_random); +#endif + #ifdef CONFIG_64BIT build_get_pgd_vmalloc64(&p, &l, &r, K0, K1); #endif @@ -733,7 +844,9 @@ static void __cpuinit build_r4000_tlb_refill_handler(void) uasm_copy_handler(relocs, labels, tlb_handler, p, f); final_len = p - tlb_handler; } else { -#ifdef MODULE_START +#if defined(CONFIG_HUGETLB_PAGE) + const enum label_id ls = label_tlb_huge_update; +#elif defined(MODULE_START) const enum label_id ls = label_module_alloc; #else const enum label_id ls = label_vmalloc; @@ -1130,6 +1243,15 @@ build_r4000_tlbchange_handler_head(u32 **p, struct uasm_label **l, build_get_pgde32(p, pte, ptr); /* get pgd in ptr */ #endif +#ifdef CONFIG_HUGETLB_PAGE + /* + * For huge tlb entries, pmd doesn't contain an address but + * instead contains the tlb pte. Check the PAGE_HUGE bit and + * see if we need to jump to huge tlb processing. + */ + build_is_huge_pte(p, r, pte, ptr, label_tlb_huge_update); +#endif + UASM_i_MFC0(p, pte, C0_BADVADDR); UASM_i_LW(p, ptr, 0, ptr); UASM_i_SRL(p, pte, pte, PAGE_SHIFT + PTE_ORDER - PTE_T_LOG2); @@ -1187,6 +1309,19 @@ static void __cpuinit build_r4000_tlb_load_handler(void) build_make_valid(&p, &r, K0, K1); build_r4000_tlbchange_handler_tail(&p, &l, &r, K0, K1); +#ifdef CONFIG_HUGETLB_PAGE + /* + * This is the entry point when build_r4000_tlbchange_handler_head + * spots a huge page. + */ + uasm_l_tlb_huge_update(&l, p); + iPTE_LW(&p, K0, K1); + build_pte_present(&p, &r, K0, K1, label_nopage_tlbl); + build_tlb_probe_entry(&p); + uasm_i_ori(&p, K0, K0, (_PAGE_ACCESSED | _PAGE_VALID)); + build_huge_handler_tail(&p, &r, &l, K0, K1); +#endif + uasm_l_nopage_tlbl(&l, p); uasm_i_j(&p, (unsigned long)tlb_do_page_fault_0 & 0x0fffffff); uasm_i_nop(&p); @@ -1218,6 +1353,20 @@ static void __cpuinit build_r4000_tlb_store_handler(void) build_make_write(&p, &r, K0, K1); build_r4000_tlbchange_handler_tail(&p, &l, &r, K0, K1); +#ifdef CONFIG_HUGETLB_PAGE + /* + * This is the entry point when + * build_r4000_tlbchange_handler_head spots a huge page. + */ + uasm_l_tlb_huge_update(&l, p); + iPTE_LW(&p, K0, K1); + build_pte_writable(&p, &r, K0, K1, label_nopage_tlbs); + build_tlb_probe_entry(&p); + uasm_i_ori(&p, K0, K0, + _PAGE_ACCESSED | _PAGE_MODIFIED | _PAGE_VALID | _PAGE_DIRTY); + build_huge_handler_tail(&p, &r, &l, K0, K1); +#endif + uasm_l_nopage_tlbs(&l, p); uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff); uasm_i_nop(&p); @@ -1250,6 +1399,20 @@ static void __cpuinit build_r4000_tlb_modify_handler(void) build_make_write(&p, &r, K0, K1); build_r4000_tlbchange_handler_tail(&p, &l, &r, K0, K1); +#ifdef CONFIG_HUGETLB_PAGE + /* + * This is the entry point when + * build_r4000_tlbchange_handler_head spots a huge page. + */ + uasm_l_tlb_huge_update(&l, p); + iPTE_LW(&p, K0, K1); + build_pte_modifiable(&p, &r, K0, K1, label_nopage_tlbm); + build_tlb_probe_entry(&p); + uasm_i_ori(&p, K0, K0, + _PAGE_ACCESSED | _PAGE_MODIFIED | _PAGE_VALID | _PAGE_DIRTY); + build_huge_handler_tail(&p, &r, &l, K0, K1); +#endif + uasm_l_nopage_tlbm(&l, p); uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff); uasm_i_nop(&p);