#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 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("noreplacement", noreplacement_setup);
__setup("smp-alt-boot", bootonly);
__setup("debug-alternative", debug_alt);
#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[];
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);
}
}
static void alternatives_smp_unlock(u8 **start, u8 **end, u8 *text, u8 *text_end)
{
- unsigned char **noptable = find_nop_table();
u8 **ptr;
for (ptr = start; ptr < end; ptr++) {
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)
- return;
-
if (smp_alt_once) {
if (boot_cpu_has(X86_FEATURE_UP))
alternatives_smp_unlock(locks, locks_end,
struct smp_alt_module *item;
unsigned long flags;
- if (no_replacement || smp_alt_once)
+ if (smp_alt_once)
return;
spin_lock_irqsave(&smp_alt, flags);
return;
#endif
- if (no_replacement || smp_alt_once)
+ if (smp_alt_once)
return;
BUG_ON(!smp && (num_online_cpus() > 1));
#endif
+#ifdef CONFIG_PARAVIRT
+void apply_paravirt(struct paravirt_patch *start, struct paravirt_patch *end)
+{
+ struct paravirt_patch *p;
+
+ for (p = start; p < end; p++) {
+ unsigned int used;
+
+ used = paravirt_ops.patch(p->instrtype, p->clobbers, p->instr,
+ p->len);
+#ifdef CONFIG_DEBUG_PARAVIRT
+ {
+ int i;
+ /* Deliberately clobber regs using "not %reg" to find bugs. */
+ for (i = 0; i < 3; i++) {
+ if (p->len - used >= 2 && (p->clobbers & (1 << i))) {
+ memcpy(p->instr + used, "\xf7\xd0", 2);
+ p->instr[used+1] |= i;
+ used += 2;
+ }
+ }
+ }
+#endif
+ /* 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 __start_parainstructions[],
+ __stop_parainstructions[];
+#endif /* CONFIG_PARAVIRT */
+
void __init alternative_instructions(void)
{
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);
- return;
- }
local_irq_save(flags);
apply_alternatives(__alt_instructions, __alt_instructions_end);
alternatives_smp_switch(0);
}
#endif
+ apply_paravirt(__start_parainstructions, __stop_parainstructions);
local_irq_restore(flags);
}