diff options
Diffstat (limited to 'arch/i386/kernel/paravirt.c')
| -rw-r--r-- | arch/i386/kernel/paravirt.c | 89 |
1 files changed, 67 insertions, 22 deletions
diff --git a/arch/i386/kernel/paravirt.c b/arch/i386/kernel/paravirt.c index faab09abca5e..739cfb207dd7 100644 --- a/arch/i386/kernel/paravirt.c +++ b/arch/i386/kernel/paravirt.c @@ -69,7 +69,8 @@ DEF_NATIVE(read_tsc, "rdtsc"); DEF_NATIVE(ud2a, "ud2a"); -static unsigned native_patch(u8 type, u16 clobbers, void *insns, unsigned len) +static unsigned native_patch(u8 type, u16 clobbers, void *ibuf, + unsigned long addr, unsigned len) { const unsigned char *start, *end; unsigned ret; @@ -90,7 +91,7 @@ static unsigned native_patch(u8 type, u16 clobbers, void *insns, unsigned len) #undef SITE patch_site: - ret = paravirt_patch_insns(insns, len, start, end); + ret = paravirt_patch_insns(ibuf, len, start, end); break; case PARAVIRT_PATCH(make_pgd): @@ -107,7 +108,7 @@ static unsigned native_patch(u8 type, u16 clobbers, void *insns, unsigned len) break; default: - ret = paravirt_patch_default(type, clobbers, insns, len); + ret = paravirt_patch_default(type, clobbers, ibuf, addr, len); break; } @@ -124,63 +125,72 @@ unsigned paravirt_patch_ignore(unsigned len) return len; } -unsigned paravirt_patch_call(void *target, u16 tgt_clobbers, - void *site, u16 site_clobbers, +struct branch { + unsigned char opcode; + u32 delta; +} __attribute__((packed)); + +unsigned paravirt_patch_call(void *insnbuf, + const void *target, u16 tgt_clobbers, + unsigned long addr, u16 site_clobbers, unsigned len) { - unsigned char *call = site; - unsigned long delta = (unsigned long)target - (unsigned long)(call+5); + struct branch *b = insnbuf; + unsigned long delta = (unsigned long)target - (addr+5); 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); return 5; } -unsigned paravirt_patch_jmp(void *target, void *site, unsigned len) +unsigned paravirt_patch_jmp(const void *target, void *insnbuf, + unsigned long addr, unsigned len) { - unsigned char *jmp = site; - unsigned long delta = (unsigned long)target - (unsigned long)(jmp+5); + struct branch *b = insnbuf; + unsigned long delta = (unsigned long)target - (addr+5); 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; return 5; } -unsigned paravirt_patch_default(u8 type, u16 clobbers, void *site, unsigned len) +unsigned paravirt_patch_default(u8 type, u16 clobbers, void *insnbuf, + unsigned long addr, unsigned len) { void *opfunc = *((void **)¶virt_ops + type); unsigned ret; if (opfunc == NULL) /* If there's no function, patch it with a ud2a (BUG) */ - ret = paravirt_patch_insns(site, len, start_ud2a, end_ud2a); + ret = paravirt_patch_insns(insnbuf, len, start_ud2a, end_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)) /* If operation requires a jmp, then jmp */ - ret = paravirt_patch_jmp(opfunc, site, len); + ret = paravirt_patch_jmp(opfunc, insnbuf, addr, len); else /* Otherwise call the function; assume target could clobber any caller-save reg */ - ret = paravirt_patch_call(opfunc, CLBR_ANY, - site, clobbers, len); + ret = paravirt_patch_call(insnbuf, opfunc, CLBR_ANY, + addr, clobbers, len); return ret; } -unsigned paravirt_patch_insns(void *site, unsigned len, +unsigned paravirt_patch_insns(void *insnbuf, unsigned len, const char *start, const char *end) { unsigned insn_len = end - start; @@ -188,7 +198,7 @@ unsigned paravirt_patch_insns(void *site, unsigned len, if (insn_len > len || start == NULL) insn_len = len; else - memcpy(site, start, insn_len); + memcpy(insnbuf, start, insn_len); return insn_len; } @@ -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, |