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Diffstat (limited to 'arch/i386/kernel/paravirt.c')
-rw-r--r--arch/i386/kernel/paravirt.c55
1 files changed, 50 insertions, 5 deletions
diff --git a/arch/i386/kernel/paravirt.c b/arch/i386/kernel/paravirt.c
index faab09abca5..ea962c0667d 100644
--- a/arch/i386/kernel/paravirt.c
+++ b/arch/i386/kernel/paravirt.c
@@ -124,20 +124,28 @@ unsigned paravirt_patch_ignore(unsigned len)
return len;
}
+struct branch {
+ unsigned char opcode;
+ u32 delta;
+} __attribute__((packed));
+
unsigned paravirt_patch_call(void *target, u16 tgt_clobbers,
void *site, u16 site_clobbers,
unsigned len)
{
unsigned char *call = site;
unsigned long delta = (unsigned long)target - (unsigned long)(call+5);
+ struct branch b;
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 */
- *call++ = 0xe8; /* call */
- *(unsigned long *)call = delta;
+ b.opcode = 0xe8; /* call */
+ b.delta = delta;
+ BUILD_BUG_ON(sizeof(b) != 5);
+ text_poke(call, (unsigned char *)&b, 5);
return 5;
}
@@ -146,12 +154,14 @@ unsigned paravirt_patch_jmp(void *target, void *site, unsigned len)
{
unsigned char *jmp = site;
unsigned long delta = (unsigned long)target - (unsigned long)(jmp+5);
+ struct branch b;
if (len < 5)
return len; /* call too long for patch site */
- *jmp++ = 0xe9; /* jmp */
- *(unsigned long *)jmp = delta;
+ b.opcode = 0xe9; /* jmp */
+ b.delta = delta;
+ text_poke(jmp, (unsigned char *)&b, 5);
return 5;
}
@@ -228,6 +238,41 @@ static int __init print_banner(void)
}
core_initcall(print_banner);
+static struct resource reserve_ioports = {
+ .start = 0,
+ .end = IO_SPACE_LIMIT,
+ .name = "paravirt-ioport",
+ .flags = IORESOURCE_IO | IORESOURCE_BUSY,
+};
+
+static struct resource reserve_iomem = {
+ .start = 0,
+ .end = -1,
+ .name = "paravirt-iomem",
+ .flags = IORESOURCE_MEM | 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)
+{
+ int ret;
+
+ ret = request_resource(&ioport_resource, &reserve_ioports);
+ if (ret == 0) {
+ ret = request_resource(&iomem_resource, &reserve_iomem);
+ if (ret)
+ release_resource(&reserve_ioports);
+ }
+
+ return ret;
+}
+
struct paravirt_ops paravirt_ops = {
.name = "bare hardware",
.paravirt_enabled = 0,
@@ -267,7 +312,7 @@ struct paravirt_ops paravirt_ops = {
.write_msr = native_write_msr_safe,
.read_tsc = native_read_tsc,
.read_pmc = native_read_pmc,
- .get_scheduled_cycles = native_read_tsc,
+ .sched_clock = native_sched_clock,
.get_cpu_khz = native_calculate_cpu_khz,
.load_tr_desc = native_load_tr_desc,
.set_ldt = native_set_ldt,