From 9e9a367c29cebd25a356d53414612e115efdadcf Mon Sep 17 00:00:00 2001 From: Christoffer Dall Date: Sun, 20 Jan 2013 18:43:10 -0500 Subject: ARM: Section based HYP idmap Add a method (hyp_idmap_setup) to populate a hyp pgd with an identity mapping of the code contained in the .hyp.idmap.text section. Offer a method to drop this identity mapping through hyp_idmap_teardown. Make all the above depend on CONFIG_ARM_VIRT_EXT and CONFIG_ARM_LPAE. Reviewed-by: Will Deacon Reviewed-by: Marcelo Tosatti Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall --- arch/arm/mm/idmap.c | 55 ++++++++++++++++++++++++++++++++++++++++++----------- 1 file changed, 44 insertions(+), 11 deletions(-) (limited to 'arch/arm/mm/idmap.c') diff --git a/arch/arm/mm/idmap.c b/arch/arm/mm/idmap.c index 99db769307ec..2dffc010cc41 100644 --- a/arch/arm/mm/idmap.c +++ b/arch/arm/mm/idmap.c @@ -1,4 +1,6 @@ +#include #include +#include #include #include @@ -6,6 +8,7 @@ #include #include #include +#include pgd_t *idmap_pgd; @@ -59,11 +62,17 @@ static void idmap_add_pud(pgd_t *pgd, unsigned long addr, unsigned long end, } while (pud++, addr = next, addr != end); } -static void identity_mapping_add(pgd_t *pgd, unsigned long addr, unsigned long end) +static void identity_mapping_add(pgd_t *pgd, const char *text_start, + const char *text_end, unsigned long prot) { - unsigned long prot, next; + unsigned long addr, end; + unsigned long next; + + addr = virt_to_phys(text_start); + end = virt_to_phys(text_end); + + prot |= PMD_TYPE_SECT | PMD_SECT_AP_WRITE | PMD_SECT_AF; - prot = PMD_TYPE_SECT | PMD_SECT_AP_WRITE | PMD_SECT_AF; if (cpu_architecture() <= CPU_ARCH_ARMv5TEJ && !cpu_is_xscale()) prot |= PMD_BIT4; @@ -74,28 +83,52 @@ static void identity_mapping_add(pgd_t *pgd, unsigned long addr, unsigned long e } while (pgd++, addr = next, addr != end); } +#if defined(CONFIG_ARM_VIRT_EXT) && defined(CONFIG_ARM_LPAE) +pgd_t *hyp_pgd; + +extern char __hyp_idmap_text_start[], __hyp_idmap_text_end[]; + +static int __init init_static_idmap_hyp(void) +{ + hyp_pgd = kzalloc(PTRS_PER_PGD * sizeof(pgd_t), GFP_KERNEL); + if (!hyp_pgd) + return -ENOMEM; + + pr_info("Setting up static HYP identity map for 0x%p - 0x%p\n", + __hyp_idmap_text_start, __hyp_idmap_text_end); + identity_mapping_add(hyp_pgd, __hyp_idmap_text_start, + __hyp_idmap_text_end, PMD_SECT_AP1); + + return 0; +} +#else +static int __init init_static_idmap_hyp(void) +{ + return 0; +} +#endif + extern char __idmap_text_start[], __idmap_text_end[]; static int __init init_static_idmap(void) { - phys_addr_t idmap_start, idmap_end; + int ret; idmap_pgd = pgd_alloc(&init_mm); if (!idmap_pgd) return -ENOMEM; - /* Add an identity mapping for the physical address of the section. */ - idmap_start = virt_to_phys((void *)__idmap_text_start); - idmap_end = virt_to_phys((void *)__idmap_text_end); + pr_info("Setting up static identity map for 0x%p - 0x%p\n", + __idmap_text_start, __idmap_text_end); + identity_mapping_add(idmap_pgd, __idmap_text_start, + __idmap_text_end, 0); - pr_info("Setting up static identity map for 0x%llx - 0x%llx\n", - (long long)idmap_start, (long long)idmap_end); - identity_mapping_add(idmap_pgd, idmap_start, idmap_end); + ret = init_static_idmap_hyp(); /* Flush L1 for the hardware to see this page table content */ flush_cache_louis(); - return 0; + return ret; } early_initcall(init_static_idmap); -- cgit v1.2.3 From 89c7e4b8bbb3d4fa52df5746a8ad38e610143651 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Thu, 28 Feb 2013 17:48:40 +0100 Subject: ARM: 7661/1: mm: perform explicit branch predictor maintenance when required The ARM ARM requires branch predictor maintenance if, for a given ASID, the instructions at a specific virtual address appear to change. From the kernel's point of view, that means: - Changing the kernel's view of memory (e.g. switching to the identity map) - ASID rollover (since ASIDs will be re-allocated to new tasks) This patch adds explicit branch predictor maintenance when either of the two conditions above are met. Reviewed-by: Catalin Marinas Signed-off-by: Will Deacon Signed-off-by: Russell King --- arch/arm/kernel/smp.c | 1 + arch/arm/kernel/suspend.c | 1 + arch/arm/mm/context.c | 4 +++- arch/arm/mm/idmap.c | 1 + 4 files changed, 6 insertions(+), 1 deletion(-) (limited to 'arch/arm/mm/idmap.c') diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 1bdfd87c8e41..31644f1978d5 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -285,6 +285,7 @@ asmlinkage void __cpuinit secondary_start_kernel(void) * switch away from it before attempting any exclusive accesses. */ cpu_switch_mm(mm->pgd, mm); + local_flush_bp_all(); enter_lazy_tlb(mm, current); local_flush_tlb_all(); diff --git a/arch/arm/kernel/suspend.c b/arch/arm/kernel/suspend.c index 358bca3a995e..c59c97ea8268 100644 --- a/arch/arm/kernel/suspend.c +++ b/arch/arm/kernel/suspend.c @@ -68,6 +68,7 @@ int cpu_suspend(unsigned long arg, int (*fn)(unsigned long)) ret = __cpu_suspend(arg, fn); if (ret == 0) { cpu_switch_mm(mm->pgd, mm); + local_flush_bp_all(); local_flush_tlb_all(); } diff --git a/arch/arm/mm/context.c b/arch/arm/mm/context.c index 44d4ee52f3e2..a5a4b2bc42ba 100644 --- a/arch/arm/mm/context.c +++ b/arch/arm/mm/context.c @@ -212,8 +212,10 @@ void check_and_switch_context(struct mm_struct *mm, struct task_struct *tsk) atomic64_set(&mm->context.id, asid); } - if (cpumask_test_and_clear_cpu(cpu, &tlb_flush_pending)) + if (cpumask_test_and_clear_cpu(cpu, &tlb_flush_pending)) { + local_flush_bp_all(); local_flush_tlb_all(); + } atomic64_set(&per_cpu(active_asids, cpu), asid); cpumask_set_cpu(cpu, mm_cpumask(mm)); diff --git a/arch/arm/mm/idmap.c b/arch/arm/mm/idmap.c index 2dffc010cc41..5ee505c937d1 100644 --- a/arch/arm/mm/idmap.c +++ b/arch/arm/mm/idmap.c @@ -141,6 +141,7 @@ void setup_mm_for_reboot(void) { /* Switch to the identity mapping. */ cpu_switch_mm(idmap_pgd, &init_mm); + local_flush_bp_all(); #ifdef CONFIG_CPU_HAS_ASID /* -- cgit v1.2.3