diff options
Diffstat (limited to 'arch/x86/kernel/paravirt.c')
| -rw-r--r-- | arch/x86/kernel/paravirt.c | 177 |
1 files changed, 23 insertions, 154 deletions
diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c index 975f98d5eee5..ab3e172dcc69 100644 --- a/arch/x86/kernel/paravirt.c +++ b/arch/x86/kernel/paravirt.c @@ -33,15 +33,10 @@ #include <asm/tlb.h> #include <asm/io_bitmap.h> #include <asm/gsseg.h> - -/* - * nop stub, which must not clobber anything *including the stack* to - * avoid confusing the entry prologues. - */ -DEFINE_PARAVIRT_ASM(_paravirt_nop, "", .entry.text); +#include <asm/msr.h> /* stub always returning 0. */ -DEFINE_PARAVIRT_ASM(paravirt_ret0, "xor %eax,%eax", .entry.text); +DEFINE_ASM_FUNC(paravirt_ret0, "xor %eax,%eax", .entry.text); void __init default_banner(void) { @@ -49,62 +44,20 @@ void __init default_banner(void) pv_info.name); } -/* Undefined instruction for dealing with missing ops pointers. */ -noinstr void paravirt_BUG(void) -{ - BUG(); -} - -static unsigned paravirt_patch_call(void *insn_buff, const void *target, - unsigned long addr, unsigned len) -{ - __text_gen_insn(insn_buff, CALL_INSN_OPCODE, - (void *)addr, target, CALL_INSN_SIZE); - return CALL_INSN_SIZE; -} - #ifdef CONFIG_PARAVIRT_XXL -DEFINE_PARAVIRT_ASM(_paravirt_ident_64, "mov %rdi, %rax", .text); -DEFINE_PARAVIRT_ASM(pv_native_save_fl, "pushf; pop %rax", .noinstr.text); -DEFINE_PARAVIRT_ASM(pv_native_irq_disable, "cli", .noinstr.text); -DEFINE_PARAVIRT_ASM(pv_native_irq_enable, "sti", .noinstr.text); -DEFINE_PARAVIRT_ASM(pv_native_read_cr2, "mov %cr2, %rax", .noinstr.text); +DEFINE_ASM_FUNC(_paravirt_ident_64, "mov %rdi, %rax", .text); +DEFINE_ASM_FUNC(pv_native_save_fl, "pushf; pop %rax", .noinstr.text); +DEFINE_ASM_FUNC(pv_native_irq_disable, "cli", .noinstr.text); +DEFINE_ASM_FUNC(pv_native_irq_enable, "sti", .noinstr.text); +DEFINE_ASM_FUNC(pv_native_read_cr2, "mov %cr2, %rax", .noinstr.text); #endif -DEFINE_STATIC_KEY_TRUE(virt_spin_lock_key); +DEFINE_STATIC_KEY_FALSE(virt_spin_lock_key); void __init native_pv_lock_init(void) { - if (IS_ENABLED(CONFIG_PARAVIRT_SPINLOCKS) && - !boot_cpu_has(X86_FEATURE_HYPERVISOR)) - static_branch_disable(&virt_spin_lock_key); -} - -static void native_tlb_remove_table(struct mmu_gather *tlb, void *table) -{ - tlb_remove_page(tlb, table); -} - -unsigned int paravirt_patch(u8 type, void *insn_buff, unsigned long addr, - unsigned int len) -{ - /* - * Neat trick to map patch type back to the call within the - * corresponding structure. - */ - void *opfunc = *((void **)&pv_ops + type); - unsigned ret; - - if (opfunc == NULL) - /* If there's no function, patch it with paravirt_BUG() */ - ret = paravirt_patch_call(insn_buff, paravirt_BUG, addr, len); - else if (opfunc == _paravirt_nop) - ret = 0; - else - /* Otherwise call the function. */ - ret = paravirt_patch_call(insn_buff, opfunc, addr, len); - - return ret; + if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) + static_branch_enable(&virt_spin_lock_key); } struct static_key paravirt_steal_enabled; @@ -123,89 +76,25 @@ void paravirt_set_sched_clock(u64 (*func)(void)) static_call_update(pv_sched_clock, func); } -/* These are in entry.S */ -static struct resource reserve_ioports = { - .start = 0, - .end = IO_SPACE_LIMIT, - .name = "paravirt-ioport", - .flags = IORESOURCE_IO | IORESOURCE_BUSY, -}; - -/* - * Reserve the whole legacy IO space to prevent any legacy drivers - * from wasting time probing for their hardware. This is a fairly - * brute-force approach to disabling all non-virtual drivers. - * - * Note that this must be called very early to have any effect. - */ -int paravirt_disable_iospace(void) -{ - return request_resource(&ioport_resource, &reserve_ioports); -} - -static DEFINE_PER_CPU(enum paravirt_lazy_mode, paravirt_lazy_mode) = PARAVIRT_LAZY_NONE; - -static inline void enter_lazy(enum paravirt_lazy_mode mode) -{ - BUG_ON(this_cpu_read(paravirt_lazy_mode) != PARAVIRT_LAZY_NONE); - - this_cpu_write(paravirt_lazy_mode, mode); -} - -static void leave_lazy(enum paravirt_lazy_mode mode) -{ - BUG_ON(this_cpu_read(paravirt_lazy_mode) != mode); - - this_cpu_write(paravirt_lazy_mode, PARAVIRT_LAZY_NONE); -} - -void paravirt_enter_lazy_mmu(void) -{ - enter_lazy(PARAVIRT_LAZY_MMU); -} - -void paravirt_leave_lazy_mmu(void) -{ - leave_lazy(PARAVIRT_LAZY_MMU); -} - -void paravirt_flush_lazy_mmu(void) +static noinstr void pv_native_safe_halt(void) { - preempt_disable(); - - if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU) { - arch_leave_lazy_mmu_mode(); - arch_enter_lazy_mmu_mode(); - } - - preempt_enable(); + native_safe_halt(); } #ifdef CONFIG_PARAVIRT_XXL -void paravirt_start_context_switch(struct task_struct *prev) +static noinstr void pv_native_write_cr2(unsigned long val) { - BUG_ON(preemptible()); - - if (this_cpu_read(paravirt_lazy_mode) == PARAVIRT_LAZY_MMU) { - arch_leave_lazy_mmu_mode(); - set_ti_thread_flag(task_thread_info(prev), TIF_LAZY_MMU_UPDATES); - } - enter_lazy(PARAVIRT_LAZY_CPU); + native_write_cr2(val); } -void paravirt_end_context_switch(struct task_struct *next) +static noinstr unsigned long pv_native_read_cr3(void) { - BUG_ON(preemptible()); - - leave_lazy(PARAVIRT_LAZY_CPU); - - if (test_and_clear_ti_thread_flag(task_thread_info(next), TIF_LAZY_MMU_UPDATES)) - arch_enter_lazy_mmu_mode(); + return __native_read_cr3(); } -static noinstr void pv_native_write_cr2(unsigned long val) +static noinstr void pv_native_write_cr3(unsigned long cr3) { - native_write_cr2(val); + native_write_cr3(cr3); } static noinstr unsigned long pv_native_get_debugreg(int regno) @@ -217,26 +106,8 @@ static noinstr void pv_native_set_debugreg(int regno, unsigned long val) { native_set_debugreg(regno, val); } - -noinstr void pv_native_wbinvd(void) -{ - native_wbinvd(); -} - -static noinstr void pv_native_safe_halt(void) -{ - native_safe_halt(); -} #endif -enum paravirt_lazy_mode paravirt_get_lazy_mode(void) -{ - if (in_interrupt()) - return PARAVIRT_LAZY_NONE; - - return this_cpu_read(paravirt_lazy_mode); -} - struct pv_info pv_info = { .name = "bare hardware", #ifdef CONFIG_PARAVIRT_XXL @@ -258,7 +129,6 @@ struct paravirt_patch_template pv_ops = { .cpu.read_cr0 = native_read_cr0, .cpu.write_cr0 = native_write_cr0, .cpu.write_cr4 = native_write_cr4, - .cpu.wbinvd = pv_native_wbinvd, .cpu.read_msr = native_read_msr, .cpu.write_msr = native_write_msr, .cpu.read_msr_safe = native_read_msr_safe, @@ -292,16 +162,17 @@ struct paravirt_patch_template pv_ops = { .irq.save_fl = __PV_IS_CALLEE_SAVE(pv_native_save_fl), .irq.irq_disable = __PV_IS_CALLEE_SAVE(pv_native_irq_disable), .irq.irq_enable = __PV_IS_CALLEE_SAVE(pv_native_irq_enable), +#endif /* CONFIG_PARAVIRT_XXL */ + + /* Irq HLT ops. */ .irq.safe_halt = pv_native_safe_halt, .irq.halt = native_halt, -#endif /* CONFIG_PARAVIRT_XXL */ /* Mmu ops. */ .mmu.flush_tlb_user = native_flush_tlb_local, .mmu.flush_tlb_kernel = native_flush_tlb_global, .mmu.flush_tlb_one_user = native_flush_tlb_one_user, .mmu.flush_tlb_multi = native_flush_tlb_multi, - .mmu.tlb_remove_table = native_tlb_remove_table, .mmu.exit_mmap = paravirt_nop, .mmu.notify_page_enc_status_changed = paravirt_nop, @@ -309,8 +180,8 @@ struct paravirt_patch_template pv_ops = { #ifdef CONFIG_PARAVIRT_XXL .mmu.read_cr2 = __PV_IS_CALLEE_SAVE(pv_native_read_cr2), .mmu.write_cr2 = pv_native_write_cr2, - .mmu.read_cr3 = __native_read_cr3, - .mmu.write_cr3 = native_write_cr3, + .mmu.read_cr3 = pv_native_read_cr3, + .mmu.write_cr3 = pv_native_write_cr3, .mmu.pgd_alloc = __paravirt_pgd_alloc, .mmu.pgd_free = paravirt_nop, @@ -340,12 +211,10 @@ struct paravirt_patch_template pv_ops = { .mmu.set_p4d = native_set_p4d, -#if CONFIG_PGTABLE_LEVELS >= 5 .mmu.p4d_val = PTE_IDENT, .mmu.make_p4d = PTE_IDENT, .mmu.set_pgd = native_set_pgd, -#endif /* CONFIG_PGTABLE_LEVELS >= 5 */ .mmu.pte_val = PTE_IDENT, .mmu.pgd_val = PTE_IDENT, |