398 lines
9.5 KiB
C
398 lines
9.5 KiB
C
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// SPDX-License-Identifier: GPL-2.0-or-later
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/* Paravirtualization interfaces
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Copyright (C) 2006 Rusty Russell IBM Corporation
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2007 - x86_64 support added by Glauber de Oliveira Costa, Red Hat Inc
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*/
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#include <linux/errno.h>
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#include <linux/init.h>
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#include <linux/export.h>
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#include <linux/efi.h>
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#include <linux/bcd.h>
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#include <linux/highmem.h>
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#include <linux/kprobes.h>
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#include <linux/pgtable.h>
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#include <linux/static_call.h>
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#include <asm/bug.h>
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#include <asm/paravirt.h>
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#include <asm/debugreg.h>
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#include <asm/desc.h>
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#include <asm/setup.h>
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#include <asm/time.h>
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#include <asm/pgalloc.h>
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#include <asm/irq.h>
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#include <asm/delay.h>
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#include <asm/fixmap.h>
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#include <asm/apic.h>
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#include <asm/tlbflush.h>
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#include <asm/timer.h>
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#include <asm/special_insns.h>
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#include <asm/tlb.h>
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#include <asm/io_bitmap.h>
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#include <asm/gsseg.h>
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/*
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* nop stub, which must not clobber anything *including the stack* to
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* avoid confusing the entry prologues.
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*/
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DEFINE_PARAVIRT_ASM(_paravirt_nop, "", .entry.text);
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/* stub always returning 0. */
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DEFINE_PARAVIRT_ASM(paravirt_ret0, "xor %eax,%eax", .entry.text);
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void __init default_banner(void)
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{
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printk(KERN_INFO "Booting paravirtualized kernel on %s\n",
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pv_info.name);
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}
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/* Undefined instruction for dealing with missing ops pointers. */
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noinstr void paravirt_BUG(void)
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{
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BUG();
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}
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static unsigned paravirt_patch_call(void *insn_buff, const void *target,
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unsigned long addr, unsigned len)
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{
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__text_gen_insn(insn_buff, CALL_INSN_OPCODE,
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(void *)addr, target, CALL_INSN_SIZE);
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return CALL_INSN_SIZE;
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}
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#ifdef CONFIG_PARAVIRT_XXL
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/* identity function, which can be inlined */
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u64 notrace _paravirt_ident_64(u64 x)
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{
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return x;
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}
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#endif
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DEFINE_STATIC_KEY_TRUE(virt_spin_lock_key);
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void __init native_pv_lock_init(void)
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{
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if (!boot_cpu_has(X86_FEATURE_HYPERVISOR))
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static_branch_disable(&virt_spin_lock_key);
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}
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unsigned int paravirt_patch(u8 type, void *insn_buff, unsigned long addr,
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unsigned int len)
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{
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/*
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* Neat trick to map patch type back to the call within the
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* corresponding structure.
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*/
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void *opfunc = *((void **)&pv_ops + type);
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unsigned ret;
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if (opfunc == NULL)
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/* If there's no function, patch it with paravirt_BUG() */
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ret = paravirt_patch_call(insn_buff, paravirt_BUG, addr, len);
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else if (opfunc == _paravirt_nop)
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ret = 0;
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else
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/* Otherwise call the function. */
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ret = paravirt_patch_call(insn_buff, opfunc, addr, len);
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return ret;
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}
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struct static_key paravirt_steal_enabled;
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struct static_key paravirt_steal_rq_enabled;
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static u64 native_steal_clock(int cpu)
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{
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return 0;
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}
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DEFINE_STATIC_CALL(pv_steal_clock, native_steal_clock);
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DEFINE_STATIC_CALL(pv_sched_clock, native_sched_clock);
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void paravirt_set_sched_clock(u64 (*func)(void))
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{
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static_call_update(pv_sched_clock, func);
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}
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/* These are in entry.S */
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static struct resource reserve_ioports = {
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.start = 0,
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.end = IO_SPACE_LIMIT,
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.name = "paravirt-ioport",
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.flags = IORESOURCE_IO | IORESOURCE_BUSY,
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};
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/*
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* Reserve the whole legacy IO space to prevent any legacy drivers
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* from wasting time probing for their hardware. This is a fairly
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* brute-force approach to disabling all non-virtual drivers.
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*
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* Note that this must be called very early to have any effect.
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*/
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int paravirt_disable_iospace(void)
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{
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return request_resource(&ioport_resource, &reserve_ioports);
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}
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static DEFINE_PER_CPU(enum paravirt_lazy_mode, paravirt_lazy_mode) = PARAVIRT_LAZY_NONE;
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static inline void enter_lazy(enum paravirt_lazy_mode mode)
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{
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BUG_ON(this_cpu_read(paravirt_lazy_mode) != PARAVIRT_LAZY_NONE);
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this_cpu_write(paravirt_lazy_mode, mode);
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}
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static void leave_lazy(enum paravirt_lazy_mode mode)
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{
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BUG_ON(this_cpu_read(paravirt_lazy_mode) != mode);
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this_cpu_write(paravirt_lazy_mode, PARAVIRT_LAZY_NONE);
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}
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void paravirt_enter_lazy_mmu(void)
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{
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enter_lazy(PARAVIRT_LAZY_MMU);
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}
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void paravirt_leave_lazy_mmu(void)
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{
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leave_lazy(PARAVIRT_LAZY_MMU);
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}
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void paravirt_flush_lazy_mmu(void)
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{
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preempt_disable();
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if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU) {
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arch_leave_lazy_mmu_mode();
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arch_enter_lazy_mmu_mode();
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}
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preempt_enable();
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}
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#ifdef CONFIG_PARAVIRT_XXL
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void paravirt_start_context_switch(struct task_struct *prev)
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{
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BUG_ON(preemptible());
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if (this_cpu_read(paravirt_lazy_mode) == PARAVIRT_LAZY_MMU) {
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arch_leave_lazy_mmu_mode();
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set_ti_thread_flag(task_thread_info(prev), TIF_LAZY_MMU_UPDATES);
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}
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enter_lazy(PARAVIRT_LAZY_CPU);
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}
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void paravirt_end_context_switch(struct task_struct *next)
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{
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BUG_ON(preemptible());
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leave_lazy(PARAVIRT_LAZY_CPU);
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if (test_and_clear_ti_thread_flag(task_thread_info(next), TIF_LAZY_MMU_UPDATES))
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arch_enter_lazy_mmu_mode();
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}
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static noinstr unsigned long pv_native_read_cr2(void)
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{
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return native_read_cr2();
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}
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static noinstr void pv_native_write_cr2(unsigned long val)
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{
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native_write_cr2(val);
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}
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static noinstr unsigned long pv_native_get_debugreg(int regno)
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{
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return native_get_debugreg(regno);
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}
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static noinstr void pv_native_set_debugreg(int regno, unsigned long val)
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{
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native_set_debugreg(regno, val);
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}
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noinstr void pv_native_wbinvd(void)
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{
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native_wbinvd();
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}
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static noinstr void pv_native_irq_enable(void)
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{
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native_irq_enable();
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}
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static noinstr void pv_native_irq_disable(void)
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{
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native_irq_disable();
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}
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static noinstr void pv_native_safe_halt(void)
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{
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native_safe_halt();
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}
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#endif
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enum paravirt_lazy_mode paravirt_get_lazy_mode(void)
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{
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if (in_interrupt())
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return PARAVIRT_LAZY_NONE;
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return this_cpu_read(paravirt_lazy_mode);
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}
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struct pv_info pv_info = {
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.name = "bare hardware",
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#ifdef CONFIG_PARAVIRT_XXL
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.extra_user_64bit_cs = __USER_CS,
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#endif
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};
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/* 64-bit pagetable entries */
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#define PTE_IDENT __PV_IS_CALLEE_SAVE(_paravirt_ident_64)
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struct paravirt_patch_template pv_ops = {
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/* Cpu ops. */
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.cpu.io_delay = native_io_delay,
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#ifdef CONFIG_PARAVIRT_XXL
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.cpu.cpuid = native_cpuid,
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.cpu.get_debugreg = pv_native_get_debugreg,
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.cpu.set_debugreg = pv_native_set_debugreg,
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.cpu.read_cr0 = native_read_cr0,
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.cpu.write_cr0 = native_write_cr0,
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.cpu.write_cr4 = native_write_cr4,
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.cpu.wbinvd = pv_native_wbinvd,
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.cpu.read_msr = native_read_msr,
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.cpu.write_msr = native_write_msr,
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.cpu.read_msr_safe = native_read_msr_safe,
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.cpu.write_msr_safe = native_write_msr_safe,
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.cpu.read_pmc = native_read_pmc,
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.cpu.load_tr_desc = native_load_tr_desc,
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.cpu.set_ldt = native_set_ldt,
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.cpu.load_gdt = native_load_gdt,
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.cpu.load_idt = native_load_idt,
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.cpu.store_tr = native_store_tr,
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.cpu.load_tls = native_load_tls,
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.cpu.load_gs_index = native_load_gs_index,
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.cpu.write_ldt_entry = native_write_ldt_entry,
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.cpu.write_gdt_entry = native_write_gdt_entry,
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.cpu.write_idt_entry = native_write_idt_entry,
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.cpu.alloc_ldt = paravirt_nop,
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.cpu.free_ldt = paravirt_nop,
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.cpu.load_sp0 = native_load_sp0,
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#ifdef CONFIG_X86_IOPL_IOPERM
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.cpu.invalidate_io_bitmap = native_tss_invalidate_io_bitmap,
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.cpu.update_io_bitmap = native_tss_update_io_bitmap,
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#endif
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.cpu.start_context_switch = paravirt_nop,
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.cpu.end_context_switch = paravirt_nop,
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/* Irq ops. */
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.irq.save_fl = __PV_IS_CALLEE_SAVE(native_save_fl),
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.irq.irq_disable = __PV_IS_CALLEE_SAVE(pv_native_irq_disable),
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.irq.irq_enable = __PV_IS_CALLEE_SAVE(pv_native_irq_enable),
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.irq.safe_halt = pv_native_safe_halt,
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.irq.halt = native_halt,
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#endif /* CONFIG_PARAVIRT_XXL */
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/* Mmu ops. */
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.mmu.flush_tlb_user = native_flush_tlb_local,
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.mmu.flush_tlb_kernel = native_flush_tlb_global,
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.mmu.flush_tlb_one_user = native_flush_tlb_one_user,
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.mmu.flush_tlb_multi = native_flush_tlb_multi,
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.mmu.tlb_remove_table =
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(void (*)(struct mmu_gather *, void *))tlb_remove_page,
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.mmu.exit_mmap = paravirt_nop,
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.mmu.notify_page_enc_status_changed = paravirt_nop,
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#ifdef CONFIG_PARAVIRT_XXL
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.mmu.read_cr2 = __PV_IS_CALLEE_SAVE(pv_native_read_cr2),
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.mmu.write_cr2 = pv_native_write_cr2,
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.mmu.read_cr3 = __native_read_cr3,
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.mmu.write_cr3 = native_write_cr3,
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.mmu.pgd_alloc = __paravirt_pgd_alloc,
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.mmu.pgd_free = paravirt_nop,
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.mmu.alloc_pte = paravirt_nop,
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.mmu.alloc_pmd = paravirt_nop,
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.mmu.alloc_pud = paravirt_nop,
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.mmu.alloc_p4d = paravirt_nop,
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.mmu.release_pte = paravirt_nop,
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.mmu.release_pmd = paravirt_nop,
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.mmu.release_pud = paravirt_nop,
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.mmu.release_p4d = paravirt_nop,
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.mmu.set_pte = native_set_pte,
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.mmu.set_pmd = native_set_pmd,
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.mmu.ptep_modify_prot_start = __ptep_modify_prot_start,
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.mmu.ptep_modify_prot_commit = __ptep_modify_prot_commit,
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.mmu.set_pud = native_set_pud,
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.mmu.pmd_val = PTE_IDENT,
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.mmu.make_pmd = PTE_IDENT,
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.mmu.pud_val = PTE_IDENT,
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.mmu.make_pud = PTE_IDENT,
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.mmu.set_p4d = native_set_p4d,
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#if CONFIG_PGTABLE_LEVELS >= 5
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.mmu.p4d_val = PTE_IDENT,
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.mmu.make_p4d = PTE_IDENT,
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.mmu.set_pgd = native_set_pgd,
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#endif /* CONFIG_PGTABLE_LEVELS >= 5 */
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.mmu.pte_val = PTE_IDENT,
|
||
|
|
.mmu.pgd_val = PTE_IDENT,
|
||
|
|
|
||
|
|
.mmu.make_pte = PTE_IDENT,
|
||
|
|
.mmu.make_pgd = PTE_IDENT,
|
||
|
|
|
||
|
|
.mmu.dup_mmap = paravirt_nop,
|
||
|
|
.mmu.activate_mm = paravirt_nop,
|
||
|
|
|
||
|
|
.mmu.lazy_mode = {
|
||
|
|
.enter = paravirt_nop,
|
||
|
|
.leave = paravirt_nop,
|
||
|
|
.flush = paravirt_nop,
|
||
|
|
},
|
||
|
|
|
||
|
|
.mmu.set_fixmap = native_set_fixmap,
|
||
|
|
#endif /* CONFIG_PARAVIRT_XXL */
|
||
|
|
|
||
|
|
#if defined(CONFIG_PARAVIRT_SPINLOCKS)
|
||
|
|
/* Lock ops. */
|
||
|
|
#ifdef CONFIG_SMP
|
||
|
|
.lock.queued_spin_lock_slowpath = native_queued_spin_lock_slowpath,
|
||
|
|
.lock.queued_spin_unlock =
|
||
|
|
PV_CALLEE_SAVE(__native_queued_spin_unlock),
|
||
|
|
.lock.wait = paravirt_nop,
|
||
|
|
.lock.kick = paravirt_nop,
|
||
|
|
.lock.vcpu_is_preempted =
|
||
|
|
PV_CALLEE_SAVE(__native_vcpu_is_preempted),
|
||
|
|
#endif /* SMP */
|
||
|
|
#endif
|
||
|
|
};
|
||
|
|
|
||
|
|
#ifdef CONFIG_PARAVIRT_XXL
|
||
|
|
NOKPROBE_SYMBOL(native_load_idt);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
EXPORT_SYMBOL(pv_ops);
|
||
|
|
EXPORT_SYMBOL_GPL(pv_info);
|