#include <linux/module.h>
+#include <linux/sched.h>
#include <linux/spinlock.h>
#include <linux/list.h>
#include <asm/alternative.h>
#include <asm/sections.h>
-static int no_replacement = 0;
+static int noreplace_smp = 0;
static int smp_alt_once = 0;
static int debug_alternative = 0;
-static int __init noreplacement_setup(char *s)
-{
- no_replacement = 1;
- return 1;
-}
static int __init bootonly(char *str)
{
smp_alt_once = 1;
return 1;
}
+__setup("smp-alt-boot", bootonly);
+
static int __init debug_alt(char *str)
{
debug_alternative = 1;
return 1;
}
-
-__setup("noreplacement", noreplacement_setup);
-__setup("smp-alt-boot", bootonly);
__setup("debug-alternative", debug_alt);
+static int __init setup_noreplace_smp(char *str)
+{
+ noreplace_smp = 1;
+ return 1;
+}
+__setup("noreplace-smp", setup_noreplace_smp);
+
+#ifdef CONFIG_PARAVIRT
+static int noreplace_paravirt = 0;
+
+static int __init setup_noreplace_paravirt(char *str)
+{
+ noreplace_paravirt = 1;
+ return 1;
+}
+__setup("noreplace-paravirt", setup_noreplace_paravirt);
+#endif
+
#define DPRINTK(fmt, args...) if (debug_alternative) \
printk(KERN_DEBUG fmt, args)
#endif /* CONFIG_X86_64 */
+static void nop_out(void *insns, unsigned int len)
+{
+ unsigned char **noptable = find_nop_table();
+
+ while (len > 0) {
+ unsigned int noplen = len;
+ if (noplen > ASM_NOP_MAX)
+ noplen = ASM_NOP_MAX;
+ memcpy(insns, noptable[noplen], noplen);
+ insns += noplen;
+ len -= noplen;
+ }
+}
+
extern struct alt_instr __alt_instructions[], __alt_instructions_end[];
-extern struct alt_instr __smp_alt_instructions[], __smp_alt_instructions_end[];
extern u8 *__smp_locks[], *__smp_locks_end[];
-extern u8 __smp_alt_begin[], __smp_alt_end[];
-
/* Replace instructions with better alternatives for this CPU type.
This runs before SMP is initialized to avoid SMP problems with
self modifying code. This implies that assymetric systems where
void apply_alternatives(struct alt_instr *start, struct alt_instr *end)
{
- unsigned char **noptable = find_nop_table();
struct alt_instr *a;
u8 *instr;
- int diff, i, k;
+ int diff;
DPRINTK("%s: alt table %p -> %p\n", __FUNCTION__, start, end);
for (a = start; a < end; a++) {
#endif
memcpy(instr, a->replacement, a->replacementlen);
diff = a->instrlen - a->replacementlen;
- /* Pad the rest with nops */
- for (i = a->replacementlen; diff > 0; diff -= k, i += k) {
- k = diff;
- if (k > ASM_NOP_MAX)
- k = ASM_NOP_MAX;
- memcpy(a->instr + i, noptable[k], k);
- }
+ nop_out(instr + a->replacementlen, diff);
}
}
#ifdef CONFIG_SMP
-static void alternatives_smp_save(struct alt_instr *start, struct alt_instr *end)
-{
- struct alt_instr *a;
-
- DPRINTK("%s: alt table %p-%p\n", __FUNCTION__, start, end);
- for (a = start; a < end; a++) {
- memcpy(a->replacement + a->replacementlen,
- a->instr,
- a->instrlen);
- }
-}
-
-static void alternatives_smp_apply(struct alt_instr *start, struct alt_instr *end)
-{
- struct alt_instr *a;
-
- for (a = start; a < end; a++) {
- memcpy(a->instr,
- a->replacement + a->replacementlen,
- a->instrlen);
- }
-}
-
static void alternatives_smp_lock(u8 **start, u8 **end, u8 *text, u8 *text_end)
{
u8 **ptr;
static void alternatives_smp_unlock(u8 **start, u8 **end, u8 *text, u8 *text_end)
{
- unsigned char **noptable = find_nop_table();
u8 **ptr;
+ if (noreplace_smp)
+ return;
+
for (ptr = start; ptr < end; ptr++) {
if (*ptr < text)
continue;
if (*ptr > text_end)
continue;
- **ptr = noptable[1][0];
+ nop_out(*ptr, 1);
};
}
struct smp_alt_module *smp;
unsigned long flags;
- if (no_replacement)
+ if (noreplace_smp)
return;
if (smp_alt_once) {
struct smp_alt_module *item;
unsigned long flags;
- if (no_replacement || smp_alt_once)
+ if (smp_alt_once || noreplace_smp)
return;
spin_lock_irqsave(&smp_alt, flags);
return;
#endif
- if (no_replacement || smp_alt_once)
+ if (noreplace_smp || smp_alt_once)
return;
BUG_ON(!smp && (num_online_cpus() > 1));
printk(KERN_INFO "SMP alternatives: switching to SMP code\n");
clear_bit(X86_FEATURE_UP, boot_cpu_data.x86_capability);
clear_bit(X86_FEATURE_UP, cpu_data[0].x86_capability);
- alternatives_smp_apply(__smp_alt_instructions,
- __smp_alt_instructions_end);
list_for_each_entry(mod, &smp_alt_modules, next)
alternatives_smp_lock(mod->locks, mod->locks_end,
mod->text, mod->text_end);
printk(KERN_INFO "SMP alternatives: switching to UP code\n");
set_bit(X86_FEATURE_UP, boot_cpu_data.x86_capability);
set_bit(X86_FEATURE_UP, cpu_data[0].x86_capability);
- apply_alternatives(__smp_alt_instructions,
- __smp_alt_instructions_end);
list_for_each_entry(mod, &smp_alt_modules, next)
alternatives_smp_unlock(mod->locks, mod->locks_end,
mod->text, mod->text_end);
#endif
-void __init alternative_instructions(void)
+#ifdef CONFIG_PARAVIRT
+void apply_paravirt(struct paravirt_patch_site *start,
+ struct paravirt_patch_site *end)
{
- unsigned long flags;
- if (no_replacement) {
- printk(KERN_INFO "(SMP-)alternatives turned off\n");
- free_init_pages("SMP alternatives",
- (unsigned long)__smp_alt_begin,
- (unsigned long)__smp_alt_end);
+ struct paravirt_patch_site *p;
+
+ if (noreplace_paravirt)
return;
+
+ for (p = start; p < end; p++) {
+ unsigned int used;
+
+ used = paravirt_ops.patch(p->instrtype, p->clobbers, p->instr,
+ p->len);
+
+ BUG_ON(used > p->len);
+
+ /* Pad the rest with nops */
+ nop_out(p->instr + used, p->len - used);
}
+ /* Sync to be conservative, in case we patched following
+ * instructions */
+ sync_core();
+}
+extern struct paravirt_patch_site __start_parainstructions[],
+ __stop_parainstructions[];
+#endif /* CONFIG_PARAVIRT */
+
+void __init alternative_instructions(void)
+{
+ unsigned long flags;
+
local_irq_save(flags);
apply_alternatives(__alt_instructions, __alt_instructions_end);
printk(KERN_INFO "SMP alternatives: switching to UP code\n");
set_bit(X86_FEATURE_UP, boot_cpu_data.x86_capability);
set_bit(X86_FEATURE_UP, cpu_data[0].x86_capability);
- apply_alternatives(__smp_alt_instructions,
- __smp_alt_instructions_end);
alternatives_smp_unlock(__smp_locks, __smp_locks_end,
_text, _etext);
}
free_init_pages("SMP alternatives",
- (unsigned long)__smp_alt_begin,
- (unsigned long)__smp_alt_end);
+ (unsigned long)__smp_locks,
+ (unsigned long)__smp_locks_end);
} else {
- alternatives_smp_save(__smp_alt_instructions,
- __smp_alt_instructions_end);
alternatives_smp_module_add(NULL, "core kernel",
__smp_locks, __smp_locks_end,
_text, _etext);
alternatives_smp_switch(0);
}
#endif
+ apply_paravirt(__parainstructions, __parainstructions_end);
local_irq_restore(flags);
}