paravirt: refactor struct paravirt_ops into smaller pv_*_ops
This patch refactors the paravirt_ops structure into groups of
functionally related ops:
pv_info - random info, rather than function entrypoints
pv_init_ops - functions used at boot time (some for module_init too)
pv_misc_ops - lazy mode, which didn't fit well anywhere else
pv_time_ops - time-related functions
pv_cpu_ops - various privileged instruction ops
pv_irq_ops - operations for managing interrupt state
pv_apic_ops - APIC operations
pv_mmu_ops - operations for managing pagetables
There are several motivations for this:
1. Some of these ops will be general to all x86, and some will be
i386/x86-64 specific. This makes it easier to share common stuff
while allowing separate implementations where needed.
2. At the moment we must export all of paravirt_ops, but modules only
need selected parts of it. This allows us to export on a case by case
basis (and also choose which export license we want to apply).
3. Functional groupings make things a bit more readable.
Struct paravirt_ops is now only used as a template to generate
patch-site identifiers, and to extract function pointers for inserting
into jmp/calls when patching. It is only instantiated when needed.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@suse.de>
Cc: Zach Amsden <zach@vmware.com>
Cc: Avi Kivity <avi@qumranet.com>
Cc: Anthony Liguory <aliguori@us.ibm.com>
Cc: "Glauber de Oliveira Costa" <glommer@gmail.com>
Cc: Jun Nakajima <jun.nakajima@intel.com>
diff --git a/arch/x86/kernel/paravirt_32.c b/arch/x86/kernel/paravirt_32.c
index 739cfb2..fa41251 100644
--- a/arch/x86/kernel/paravirt_32.c
+++ b/arch/x86/kernel/paravirt_32.c
@@ -42,32 +42,33 @@
static void __init default_banner(void)
{
printk(KERN_INFO "Booting paravirtualized kernel on %s\n",
- paravirt_ops.name);
+ pv_info.name);
}
char *memory_setup(void)
{
- return paravirt_ops.memory_setup();
+ return pv_init_ops.memory_setup();
}
/* Simple instruction patching code. */
-#define DEF_NATIVE(name, code) \
- extern const char start_##name[], end_##name[]; \
- asm("start_" #name ": " code "; end_" #name ":")
+#define DEF_NATIVE(ops, name, code) \
+ extern const char start_##ops##_##name[], end_##ops##_##name[]; \
+ asm("start_" #ops "_" #name ": " code "; end_" #ops "_" #name ":")
-DEF_NATIVE(irq_disable, "cli");
-DEF_NATIVE(irq_enable, "sti");
-DEF_NATIVE(restore_fl, "push %eax; popf");
-DEF_NATIVE(save_fl, "pushf; pop %eax");
-DEF_NATIVE(iret, "iret");
-DEF_NATIVE(irq_enable_sysexit, "sti; sysexit");
-DEF_NATIVE(read_cr2, "mov %cr2, %eax");
-DEF_NATIVE(write_cr3, "mov %eax, %cr3");
-DEF_NATIVE(read_cr3, "mov %cr3, %eax");
-DEF_NATIVE(clts, "clts");
-DEF_NATIVE(read_tsc, "rdtsc");
+DEF_NATIVE(pv_irq_ops, irq_disable, "cli");
+DEF_NATIVE(pv_irq_ops, irq_enable, "sti");
+DEF_NATIVE(pv_irq_ops, restore_fl, "push %eax; popf");
+DEF_NATIVE(pv_irq_ops, save_fl, "pushf; pop %eax");
+DEF_NATIVE(pv_cpu_ops, iret, "iret");
+DEF_NATIVE(pv_cpu_ops, irq_enable_sysexit, "sti; sysexit");
+DEF_NATIVE(pv_mmu_ops, read_cr2, "mov %cr2, %eax");
+DEF_NATIVE(pv_mmu_ops, write_cr3, "mov %eax, %cr3");
+DEF_NATIVE(pv_mmu_ops, read_cr3, "mov %cr3, %eax");
+DEF_NATIVE(pv_cpu_ops, clts, "clts");
+DEF_NATIVE(pv_cpu_ops, read_tsc, "rdtsc");
-DEF_NATIVE(ud2a, "ud2a");
+/* Undefined instruction for dealing with missing ops pointers. */
+static const unsigned char ud2a[] = { 0x0f, 0x0b };
static unsigned native_patch(u8 type, u16 clobbers, void *ibuf,
unsigned long addr, unsigned len)
@@ -76,37 +77,29 @@
unsigned ret;
switch(type) {
-#define SITE(x) case PARAVIRT_PATCH(x): start = start_##x; end = end_##x; goto patch_site
- SITE(irq_disable);
- SITE(irq_enable);
- SITE(restore_fl);
- SITE(save_fl);
- SITE(iret);
- SITE(irq_enable_sysexit);
- SITE(read_cr2);
- SITE(read_cr3);
- SITE(write_cr3);
- SITE(clts);
- SITE(read_tsc);
+#define SITE(ops, x) \
+ case PARAVIRT_PATCH(ops.x): \
+ start = start_##ops##_##x; \
+ end = end_##ops##_##x; \
+ goto patch_site
+
+ SITE(pv_irq_ops, irq_disable);
+ SITE(pv_irq_ops, irq_enable);
+ SITE(pv_irq_ops, restore_fl);
+ SITE(pv_irq_ops, save_fl);
+ SITE(pv_cpu_ops, iret);
+ SITE(pv_cpu_ops, irq_enable_sysexit);
+ SITE(pv_mmu_ops, read_cr2);
+ SITE(pv_mmu_ops, read_cr3);
+ SITE(pv_mmu_ops, write_cr3);
+ SITE(pv_cpu_ops, clts);
+ SITE(pv_cpu_ops, read_tsc);
#undef SITE
patch_site:
ret = paravirt_patch_insns(ibuf, len, start, end);
break;
- case PARAVIRT_PATCH(make_pgd):
- case PARAVIRT_PATCH(make_pte):
- case PARAVIRT_PATCH(pgd_val):
- case PARAVIRT_PATCH(pte_val):
-#ifdef CONFIG_X86_PAE
- case PARAVIRT_PATCH(make_pmd):
- case PARAVIRT_PATCH(pmd_val):
-#endif
- /* These functions end up returning exactly what
- they're passed, in the same registers. */
- ret = paravirt_patch_nop();
- break;
-
default:
ret = paravirt_patch_default(type, clobbers, ibuf, addr, len);
break;
@@ -150,7 +143,7 @@
return 5;
}
-unsigned paravirt_patch_jmp(const void *target, void *insnbuf,
+unsigned paravirt_patch_jmp(void *insnbuf, const void *target,
unsigned long addr, unsigned len)
{
struct branch *b = insnbuf;
@@ -165,22 +158,38 @@
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_misc_ops = pv_misc_ops,
+ .pv_time_ops = pv_time_ops,
+ .pv_cpu_ops = pv_cpu_ops,
+ .pv_irq_ops = pv_irq_ops,
+ .pv_apic_ops = pv_apic_ops,
+ .pv_mmu_ops = pv_mmu_ops,
+ };
+ return *((void **)&tmpl + type);
+}
+
unsigned paravirt_patch_default(u8 type, u16 clobbers, void *insnbuf,
unsigned long addr, unsigned len)
{
- void *opfunc = *((void **)¶virt_ops + type);
+ 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, start_ud2a, end_ud2a);
+ ret = paravirt_patch_insns(insnbuf, len, ud2a, ud2a+sizeof(ud2a));
else if (opfunc == paravirt_nop)
/* If the operation is a nop, then nop the callsite */
ret = paravirt_patch_nop();
- else if (type == PARAVIRT_PATCH(iret) ||
- type == PARAVIRT_PATCH(irq_enable_sysexit))
+ else if (type == PARAVIRT_PATCH(pv_cpu_ops.iret) ||
+ type == PARAVIRT_PATCH(pv_cpu_ops.irq_enable_sysexit))
/* If operation requires a jmp, then jmp */
- ret = paravirt_patch_jmp(opfunc, insnbuf, addr, len);
+ ret = paravirt_patch_jmp(insnbuf, opfunc, addr, len);
else
/* Otherwise call the function; assume target could
clobber any caller-save reg */
@@ -205,7 +214,7 @@
void init_IRQ(void)
{
- paravirt_ops.init_IRQ();
+ pv_irq_ops.init_IRQ();
}
static void native_flush_tlb(void)
@@ -233,7 +242,7 @@
static int __init print_banner(void)
{
- paravirt_ops.banner();
+ pv_init_ops.banner();
return 0;
}
core_initcall(print_banner);
@@ -273,47 +282,53 @@
return ret;
}
-struct paravirt_ops paravirt_ops = {
+struct pv_info pv_info = {
.name = "bare hardware",
.paravirt_enabled = 0,
.kernel_rpl = 0,
.shared_kernel_pmd = 1, /* Only used when CONFIG_X86_PAE is set */
+};
- .patch = native_patch,
+struct pv_init_ops pv_init_ops = {
+ .patch = native_patch,
.banner = default_banner,
.arch_setup = paravirt_nop,
.memory_setup = machine_specific_memory_setup,
+};
+
+struct pv_time_ops pv_time_ops = {
+ .time_init = hpet_time_init,
.get_wallclock = native_get_wallclock,
.set_wallclock = native_set_wallclock,
- .time_init = hpet_time_init,
- .init_IRQ = native_init_IRQ,
+ .sched_clock = native_sched_clock,
+ .get_cpu_khz = native_calculate_cpu_khz,
+};
- .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_cr2 = native_read_cr2,
- .write_cr2 = native_write_cr2,
- .read_cr3 = native_read_cr3,
- .write_cr3 = native_write_cr3,
- .read_cr4 = native_read_cr4,
- .read_cr4_safe = native_read_cr4_safe,
- .write_cr4 = native_write_cr4,
+struct pv_irq_ops pv_irq_ops = {
+ .init_IRQ = native_init_IRQ,
.save_fl = native_save_fl,
.restore_fl = native_restore_fl,
.irq_disable = native_irq_disable,
.irq_enable = native_irq_enable,
.safe_halt = native_safe_halt,
.halt = native_halt,
+};
+
+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,
.wbinvd = native_wbinvd,
.read_msr = native_read_msr_safe,
.write_msr = native_write_msr_safe,
.read_tsc = native_read_tsc,
.read_pmc = native_read_pmc,
- .sched_clock = native_sched_clock,
- .get_cpu_khz = native_calculate_cpu_khz,
.load_tr_desc = native_load_tr_desc,
.set_ldt = native_set_ldt,
.load_gdt = native_load_gdt,
@@ -327,9 +342,14 @@
.write_idt_entry = write_dt_entry,
.load_esp0 = native_load_esp0,
+ .irq_enable_sysexit = native_irq_enable_sysexit,
+ .iret = native_iret,
+
.set_iopl_mask = native_set_iopl_mask,
.io_delay = native_io_delay,
+};
+struct pv_apic_ops pv_apic_ops = {
#ifdef CONFIG_X86_LOCAL_APIC
.apic_write = native_apic_write,
.apic_write_atomic = native_apic_write_atomic,
@@ -338,11 +358,21 @@
.setup_secondary_clock = setup_secondary_APIC_clock,
.startup_ipi_hook = paravirt_nop,
#endif
- .set_lazy_mode = paravirt_nop,
+};
+struct pv_misc_ops pv_misc_ops = {
+ .set_lazy_mode = paravirt_nop,
+};
+
+struct pv_mmu_ops pv_mmu_ops = {
.pagetable_setup_start = native_pagetable_setup_start,
.pagetable_setup_done = native_pagetable_setup_done,
+ .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,
@@ -381,12 +411,14 @@
.make_pte = native_make_pte,
.make_pgd = native_make_pgd,
- .irq_enable_sysexit = native_irq_enable_sysexit,
- .iret = native_iret,
-
.dup_mmap = paravirt_nop,
.exit_mmap = paravirt_nop,
.activate_mm = paravirt_nop,
};
-EXPORT_SYMBOL(paravirt_ops);
+EXPORT_SYMBOL_GPL(pv_time_ops);
+EXPORT_SYMBOL_GPL(pv_cpu_ops);
+EXPORT_SYMBOL_GPL(pv_mmu_ops);
+EXPORT_SYMBOL_GPL(pv_apic_ops);
+EXPORT_SYMBOL_GPL(pv_info);
+EXPORT_SYMBOL (pv_irq_ops);