diff options
Diffstat (limited to 'arch/i386/kernel/paravirt.c')
| -rw-r--r-- | arch/i386/kernel/paravirt.c | 55 |
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, |