466 строки
11 KiB
C
466 строки
11 KiB
C
/* Paravirtualization interfaces
|
|
Copyright (C) 2006 Rusty Russell IBM Corporation
|
|
|
|
This program is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 2 of the License, or
|
|
(at your option) any later version.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program; if not, write to the Free Software
|
|
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
|
|
|
2007 - x86_64 support added by Glauber de Oliveira Costa, Red Hat Inc
|
|
*/
|
|
|
|
#include <linux/errno.h>
|
|
#include <linux/init.h>
|
|
#include <linux/export.h>
|
|
#include <linux/efi.h>
|
|
#include <linux/bcd.h>
|
|
#include <linux/highmem.h>
|
|
#include <linux/kprobes.h>
|
|
|
|
#include <asm/bug.h>
|
|
#include <asm/paravirt.h>
|
|
#include <asm/debugreg.h>
|
|
#include <asm/desc.h>
|
|
#include <asm/setup.h>
|
|
#include <asm/pgtable.h>
|
|
#include <asm/time.h>
|
|
#include <asm/pgalloc.h>
|
|
#include <asm/irq.h>
|
|
#include <asm/delay.h>
|
|
#include <asm/fixmap.h>
|
|
#include <asm/apic.h>
|
|
#include <asm/tlbflush.h>
|
|
#include <asm/timer.h>
|
|
#include <asm/special_insns.h>
|
|
|
|
/*
|
|
* nop stub, which must not clobber anything *including the stack* to
|
|
* avoid confusing the entry prologues.
|
|
*/
|
|
extern void _paravirt_nop(void);
|
|
asm (".pushsection .entry.text, \"ax\"\n"
|
|
".global _paravirt_nop\n"
|
|
"_paravirt_nop:\n\t"
|
|
"ret\n\t"
|
|
".size _paravirt_nop, . - _paravirt_nop\n\t"
|
|
".type _paravirt_nop, @function\n\t"
|
|
".popsection");
|
|
|
|
/* identity function, which can be inlined */
|
|
u32 _paravirt_ident_32(u32 x)
|
|
{
|
|
return x;
|
|
}
|
|
|
|
u64 _paravirt_ident_64(u64 x)
|
|
{
|
|
return x;
|
|
}
|
|
|
|
void __init default_banner(void)
|
|
{
|
|
printk(KERN_INFO "Booting paravirtualized kernel on %s\n",
|
|
pv_info.name);
|
|
}
|
|
|
|
/* Undefined instruction for dealing with missing ops pointers. */
|
|
static const unsigned char ud2a[] = { 0x0f, 0x0b };
|
|
|
|
struct branch {
|
|
unsigned char opcode;
|
|
u32 delta;
|
|
} __attribute__((packed));
|
|
|
|
unsigned paravirt_patch_call(void *insnbuf,
|
|
const void *target, u16 tgt_clobbers,
|
|
unsigned long addr, u16 site_clobbers,
|
|
unsigned len)
|
|
{
|
|
struct branch *b = insnbuf;
|
|
unsigned long delta = (unsigned long)target - (addr+5);
|
|
|
|
if (tgt_clobbers & ~site_clobbers)
|
|
return len; /* target would clobber too much for this site */
|
|
if (len < 5)
|
|
return len; /* call too long for patch site */
|
|
|
|
b->opcode = 0xe8; /* call */
|
|
b->delta = delta;
|
|
BUILD_BUG_ON(sizeof(*b) != 5);
|
|
|
|
return 5;
|
|
}
|
|
|
|
unsigned paravirt_patch_jmp(void *insnbuf, const void *target,
|
|
unsigned long addr, unsigned len)
|
|
{
|
|
struct branch *b = insnbuf;
|
|
unsigned long delta = (unsigned long)target - (addr+5);
|
|
|
|
if (len < 5)
|
|
return len; /* call too long for patch site */
|
|
|
|
b->opcode = 0xe9; /* jmp */
|
|
b->delta = delta;
|
|
|
|
return 5;
|
|
}
|
|
|
|
/* Neat trick to map patch type back to the call within the
|
|
* corresponding structure. */
|
|
static void *get_call_destination(u8 type)
|
|
{
|
|
struct paravirt_patch_template tmpl = {
|
|
.pv_init_ops = pv_init_ops,
|
|
.pv_time_ops = pv_time_ops,
|
|
.pv_cpu_ops = pv_cpu_ops,
|
|
.pv_irq_ops = pv_irq_ops,
|
|
.pv_mmu_ops = pv_mmu_ops,
|
|
#ifdef CONFIG_PARAVIRT_SPINLOCKS
|
|
.pv_lock_ops = pv_lock_ops,
|
|
#endif
|
|
};
|
|
return *((void **)&tmpl + type);
|
|
}
|
|
|
|
unsigned paravirt_patch_default(u8 type, u16 clobbers, void *insnbuf,
|
|
unsigned long addr, unsigned len)
|
|
{
|
|
void *opfunc = get_call_destination(type);
|
|
unsigned ret;
|
|
|
|
if (opfunc == NULL)
|
|
/* If there's no function, patch it with a ud2a (BUG) */
|
|
ret = paravirt_patch_insns(insnbuf, len, ud2a, ud2a+sizeof(ud2a));
|
|
else if (opfunc == _paravirt_nop)
|
|
ret = 0;
|
|
|
|
/* identity functions just return their single argument */
|
|
else if (opfunc == _paravirt_ident_32)
|
|
ret = paravirt_patch_ident_32(insnbuf, len);
|
|
else if (opfunc == _paravirt_ident_64)
|
|
ret = paravirt_patch_ident_64(insnbuf, len);
|
|
|
|
else if (type == PARAVIRT_PATCH(pv_cpu_ops.iret) ||
|
|
type == PARAVIRT_PATCH(pv_cpu_ops.usergs_sysret64))
|
|
/* If operation requires a jmp, then jmp */
|
|
ret = paravirt_patch_jmp(insnbuf, opfunc, addr, len);
|
|
else
|
|
/* Otherwise call the function; assume target could
|
|
clobber any caller-save reg */
|
|
ret = paravirt_patch_call(insnbuf, opfunc, CLBR_ANY,
|
|
addr, clobbers, len);
|
|
|
|
return ret;
|
|
}
|
|
|
|
unsigned paravirt_patch_insns(void *insnbuf, unsigned len,
|
|
const char *start, const char *end)
|
|
{
|
|
unsigned insn_len = end - start;
|
|
|
|
if (insn_len > len || start == NULL)
|
|
insn_len = len;
|
|
else
|
|
memcpy(insnbuf, start, insn_len);
|
|
|
|
return insn_len;
|
|
}
|
|
|
|
static void native_flush_tlb(void)
|
|
{
|
|
__native_flush_tlb();
|
|
}
|
|
|
|
/*
|
|
* Global pages have to be flushed a bit differently. Not a real
|
|
* performance problem because this does not happen often.
|
|
*/
|
|
static void native_flush_tlb_global(void)
|
|
{
|
|
__native_flush_tlb_global();
|
|
}
|
|
|
|
static void native_flush_tlb_single(unsigned long addr)
|
|
{
|
|
__native_flush_tlb_single(addr);
|
|
}
|
|
|
|
struct static_key paravirt_steal_enabled;
|
|
struct static_key paravirt_steal_rq_enabled;
|
|
|
|
static u64 native_steal_clock(int cpu)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
/* These are in entry.S */
|
|
extern void native_iret(void);
|
|
extern void native_usergs_sysret64(void);
|
|
|
|
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)
|
|
{
|
|
preempt_disable();
|
|
|
|
if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU) {
|
|
arch_leave_lazy_mmu_mode();
|
|
arch_enter_lazy_mmu_mode();
|
|
}
|
|
|
|
preempt_enable();
|
|
}
|
|
|
|
void paravirt_start_context_switch(struct task_struct *prev)
|
|
{
|
|
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);
|
|
}
|
|
|
|
void paravirt_end_context_switch(struct task_struct *next)
|
|
{
|
|
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();
|
|
}
|
|
|
|
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",
|
|
.kernel_rpl = 0,
|
|
.shared_kernel_pmd = 1, /* Only used when CONFIG_X86_PAE is set */
|
|
|
|
#ifdef CONFIG_X86_64
|
|
.extra_user_64bit_cs = __USER_CS,
|
|
#endif
|
|
};
|
|
|
|
struct pv_init_ops pv_init_ops = {
|
|
.patch = native_patch,
|
|
};
|
|
|
|
struct pv_time_ops pv_time_ops = {
|
|
.sched_clock = native_sched_clock,
|
|
.steal_clock = native_steal_clock,
|
|
};
|
|
|
|
__visible struct pv_irq_ops pv_irq_ops = {
|
|
.save_fl = __PV_IS_CALLEE_SAVE(native_save_fl),
|
|
.restore_fl = __PV_IS_CALLEE_SAVE(native_restore_fl),
|
|
.irq_disable = __PV_IS_CALLEE_SAVE(native_irq_disable),
|
|
.irq_enable = __PV_IS_CALLEE_SAVE(native_irq_enable),
|
|
.safe_halt = native_safe_halt,
|
|
.halt = native_halt,
|
|
#ifdef CONFIG_X86_64
|
|
.adjust_exception_frame = paravirt_nop,
|
|
#endif
|
|
};
|
|
|
|
__visible struct pv_cpu_ops pv_cpu_ops = {
|
|
.cpuid = native_cpuid,
|
|
.get_debugreg = native_get_debugreg,
|
|
.set_debugreg = native_set_debugreg,
|
|
.clts = native_clts,
|
|
.read_cr0 = native_read_cr0,
|
|
.write_cr0 = native_write_cr0,
|
|
.read_cr4 = native_read_cr4,
|
|
.read_cr4_safe = native_read_cr4_safe,
|
|
.write_cr4 = native_write_cr4,
|
|
#ifdef CONFIG_X86_64
|
|
.read_cr8 = native_read_cr8,
|
|
.write_cr8 = native_write_cr8,
|
|
#endif
|
|
.wbinvd = native_wbinvd,
|
|
.read_msr = native_read_msr,
|
|
.write_msr = native_write_msr,
|
|
.read_msr_safe = native_read_msr_safe,
|
|
.write_msr_safe = native_write_msr_safe,
|
|
.read_pmc = native_read_pmc,
|
|
.load_tr_desc = native_load_tr_desc,
|
|
.set_ldt = native_set_ldt,
|
|
.load_gdt = native_load_gdt,
|
|
.load_idt = native_load_idt,
|
|
.store_idt = native_store_idt,
|
|
.store_tr = native_store_tr,
|
|
.load_tls = native_load_tls,
|
|
#ifdef CONFIG_X86_64
|
|
.load_gs_index = native_load_gs_index,
|
|
#endif
|
|
.write_ldt_entry = native_write_ldt_entry,
|
|
.write_gdt_entry = native_write_gdt_entry,
|
|
.write_idt_entry = native_write_idt_entry,
|
|
|
|
.alloc_ldt = paravirt_nop,
|
|
.free_ldt = paravirt_nop,
|
|
|
|
.load_sp0 = native_load_sp0,
|
|
|
|
#ifdef CONFIG_X86_64
|
|
.usergs_sysret64 = native_usergs_sysret64,
|
|
#endif
|
|
.iret = native_iret,
|
|
.swapgs = native_swapgs,
|
|
|
|
.set_iopl_mask = native_set_iopl_mask,
|
|
.io_delay = native_io_delay,
|
|
|
|
.start_context_switch = paravirt_nop,
|
|
.end_context_switch = paravirt_nop,
|
|
};
|
|
|
|
/* At this point, native_get/set_debugreg has real function entries */
|
|
NOKPROBE_SYMBOL(native_get_debugreg);
|
|
NOKPROBE_SYMBOL(native_set_debugreg);
|
|
NOKPROBE_SYMBOL(native_load_idt);
|
|
|
|
#if defined(CONFIG_X86_32) && !defined(CONFIG_X86_PAE)
|
|
/* 32-bit pagetable entries */
|
|
#define PTE_IDENT __PV_IS_CALLEE_SAVE(_paravirt_ident_32)
|
|
#else
|
|
/* 64-bit pagetable entries */
|
|
#define PTE_IDENT __PV_IS_CALLEE_SAVE(_paravirt_ident_64)
|
|
#endif
|
|
|
|
struct pv_mmu_ops pv_mmu_ops = {
|
|
|
|
.read_cr2 = native_read_cr2,
|
|
.write_cr2 = native_write_cr2,
|
|
.read_cr3 = native_read_cr3,
|
|
.write_cr3 = native_write_cr3,
|
|
|
|
.flush_tlb_user = native_flush_tlb,
|
|
.flush_tlb_kernel = native_flush_tlb_global,
|
|
.flush_tlb_single = native_flush_tlb_single,
|
|
.flush_tlb_others = native_flush_tlb_others,
|
|
|
|
.pgd_alloc = __paravirt_pgd_alloc,
|
|
.pgd_free = paravirt_nop,
|
|
|
|
.alloc_pte = paravirt_nop,
|
|
.alloc_pmd = paravirt_nop,
|
|
.alloc_pud = paravirt_nop,
|
|
.release_pte = paravirt_nop,
|
|
.release_pmd = paravirt_nop,
|
|
.release_pud = paravirt_nop,
|
|
|
|
.set_pte = native_set_pte,
|
|
.set_pte_at = native_set_pte_at,
|
|
.set_pmd = native_set_pmd,
|
|
.set_pmd_at = native_set_pmd_at,
|
|
.pte_update = paravirt_nop,
|
|
|
|
.ptep_modify_prot_start = __ptep_modify_prot_start,
|
|
.ptep_modify_prot_commit = __ptep_modify_prot_commit,
|
|
|
|
#if CONFIG_PGTABLE_LEVELS >= 3
|
|
#ifdef CONFIG_X86_PAE
|
|
.set_pte_atomic = native_set_pte_atomic,
|
|
.pte_clear = native_pte_clear,
|
|
.pmd_clear = native_pmd_clear,
|
|
#endif
|
|
.set_pud = native_set_pud,
|
|
|
|
.pmd_val = PTE_IDENT,
|
|
.make_pmd = PTE_IDENT,
|
|
|
|
#if CONFIG_PGTABLE_LEVELS == 4
|
|
.pud_val = PTE_IDENT,
|
|
.make_pud = PTE_IDENT,
|
|
|
|
.set_pgd = native_set_pgd,
|
|
#endif
|
|
#endif /* CONFIG_PGTABLE_LEVELS >= 3 */
|
|
|
|
.pte_val = PTE_IDENT,
|
|
.pgd_val = PTE_IDENT,
|
|
|
|
.make_pte = PTE_IDENT,
|
|
.make_pgd = PTE_IDENT,
|
|
|
|
.dup_mmap = paravirt_nop,
|
|
.exit_mmap = paravirt_nop,
|
|
.activate_mm = paravirt_nop,
|
|
|
|
.lazy_mode = {
|
|
.enter = paravirt_nop,
|
|
.leave = paravirt_nop,
|
|
.flush = paravirt_nop,
|
|
},
|
|
|
|
.set_fixmap = native_set_fixmap,
|
|
};
|
|
|
|
EXPORT_SYMBOL_GPL(pv_time_ops);
|
|
EXPORT_SYMBOL (pv_cpu_ops);
|
|
EXPORT_SYMBOL (pv_mmu_ops);
|
|
EXPORT_SYMBOL_GPL(pv_info);
|
|
EXPORT_SYMBOL (pv_irq_ops);
|