diff options
Diffstat (limited to 'xen/arch/x86/mm/shadow/multi.c')
| -rw-r--r-- | xen/arch/x86/mm/shadow/multi.c | 122 |
1 files changed, 74 insertions, 48 deletions
diff --git a/xen/arch/x86/mm/shadow/multi.c b/xen/arch/x86/mm/shadow/multi.c index f12a97fbde..8407beacf7 100644 --- a/xen/arch/x86/mm/shadow/multi.c +++ b/xen/arch/x86/mm/shadow/multi.c @@ -1470,10 +1470,14 @@ void sh_install_xen_entries_in_l4(struct vcpu *v, mfn_t gl4mfn, mfn_t sl4mfn) shadow_l4e_from_mfn(page_to_mfn(virt_to_page(d->arch.mm_perdomain_l3)), __PAGE_HYPERVISOR); - /* Linear mapping */ + /* Shadow linear mapping for 4-level shadows. N.B. for 3-level + * shadows on 64-bit xen, this linear mapping is later replaced by the + * monitor pagetable structure, which is built in make_monitor_table + * and maintained by sh_update_linear_entries. */ sl4e[shadow_l4_table_offset(SH_LINEAR_PT_VIRT_START)] = shadow_l4e_from_mfn(sl4mfn, __PAGE_HYPERVISOR); + /* Self linear mapping. */ if ( shadow_mode_translate(v->domain) && !shadow_mode_external(v->domain) ) { // linear tables may not be used with translated PV guests @@ -1745,7 +1749,7 @@ sh_make_monitor_table(struct vcpu *v) ASSERT(pagetable_get_pfn(v->arch.monitor_table) == 0); /* Guarantee we can get the memory we need */ - shadow_prealloc(d, SH_type_monitor_table, CONFIG_PAGING_LEVELS - 1); + shadow_prealloc(d, SH_type_monitor_table, CONFIG_PAGING_LEVELS); #if CONFIG_PAGING_LEVELS == 4 { @@ -1755,22 +1759,34 @@ sh_make_monitor_table(struct vcpu *v) /* Remember the level of this table */ mfn_to_page(m4mfn)->shadow_flags = 4; #if SHADOW_PAGING_LEVELS < 4 - // Install a monitor l3 table in slot 0 of the l4 table. - // This is used for shadow linear maps. { - mfn_t m3mfn; + mfn_t m3mfn, m2mfn; l4_pgentry_t *l4e; + l3_pgentry_t *l3e; + /* Install an l3 table and an l2 table that will hold the shadow + * linear map entries. This overrides the linear map entry that + * was installed by sh_install_xen_entries_in_l4. */ + l4e = sh_map_domain_page(m4mfn); + m3mfn = shadow_alloc(d, SH_type_monitor_table, 0); mfn_to_page(m3mfn)->shadow_flags = 3; - l4e = sh_map_domain_page(m4mfn); - l4e[0] = l4e_from_pfn(mfn_x(m3mfn), __PAGE_HYPERVISOR); - sh_unmap_domain_page(l4e); + l4e[shadow_l4_table_offset(SH_LINEAR_PT_VIRT_START)] + = l4e_from_pfn(mfn_x(m3mfn), __PAGE_HYPERVISOR); + + m2mfn = shadow_alloc(d, SH_type_monitor_table, 0); + mfn_to_page(m2mfn)->shadow_flags = 2; + l3e = sh_map_domain_page(m3mfn); + l3e[0] = l3e_from_pfn(mfn_x(m2mfn), __PAGE_HYPERVISOR); + sh_unmap_domain_page(l3e); + if ( is_pv_32on64_vcpu(v) ) { - // Install a monitor l2 table in slot 3 of the l3 table. - // This is used for all Xen entries. - mfn_t m2mfn; - l3_pgentry_t *l3e; + /* For 32-on-64 PV guests, we need to map the 32-bit Xen + * area into its usual VAs in the monitor tables */ + m3mfn = shadow_alloc(d, SH_type_monitor_table, 0); + mfn_to_page(m3mfn)->shadow_flags = 3; + l4e[0] = l4e_from_pfn(mfn_x(m3mfn), __PAGE_HYPERVISOR); + m2mfn = shadow_alloc(d, SH_type_monitor_table, 0); mfn_to_page(m2mfn)->shadow_flags = 2; l3e = sh_map_domain_page(m3mfn); @@ -1778,6 +1794,8 @@ sh_make_monitor_table(struct vcpu *v) sh_install_xen_entries_in_l2h(v, m2mfn); sh_unmap_domain_page(l3e); } + + sh_unmap_domain_page(l4e); } #endif /* SHADOW_PAGING_LEVELS < 4 */ return m4mfn; @@ -2181,21 +2199,34 @@ void sh_destroy_monitor_table(struct vcpu *v, mfn_t mmfn) ASSERT(mfn_to_shadow_page(mmfn)->type == SH_type_monitor_table); #if (CONFIG_PAGING_LEVELS == 4) && (SHADOW_PAGING_LEVELS != 4) - /* Need to destroy the l3 monitor page in slot 0 too */ { mfn_t m3mfn; l4_pgentry_t *l4e = sh_map_domain_page(mmfn); - ASSERT(l4e_get_flags(l4e[0]) & _PAGE_PRESENT); - m3mfn = _mfn(l4e_get_pfn(l4e[0])); + l3_pgentry_t *l3e; + int linear_slot = shadow_l4_table_offset(SH_LINEAR_PT_VIRT_START); + + /* Need to destroy the l3 and l2 monitor pages used + * for the linear map */ + ASSERT(l4e_get_flags(l4e[linear_slot]) & _PAGE_PRESENT); + m3mfn = _mfn(l4e_get_pfn(l4e[linear_slot])); + l3e = sh_map_domain_page(m3mfn); + ASSERT(l3e_get_flags(l3e[0]) & _PAGE_PRESENT); + shadow_free(d, _mfn(l3e_get_pfn(l3e[0]))); + sh_unmap_domain_page(l3e); + shadow_free(d, m3mfn); + if ( is_pv_32on64_vcpu(v) ) { - /* Need to destroy the l2 monitor page in slot 3 too */ - l3_pgentry_t *l3e = sh_map_domain_page(m3mfn); + /* Need to destroy the l3 and l2 monitor pages that map the + * Xen VAs at 3GB-4GB */ + ASSERT(l4e_get_flags(l4e[0]) & _PAGE_PRESENT); + m3mfn = _mfn(l4e_get_pfn(l4e[0])); + l3e = sh_map_domain_page(m3mfn); ASSERT(l3e_get_flags(l3e[3]) & _PAGE_PRESENT); shadow_free(d, _mfn(l3e_get_pfn(l3e[3]))); sh_unmap_domain_page(l3e); + shadow_free(d, m3mfn); } - shadow_free(d, m3mfn); sh_unmap_domain_page(l4e); } #elif CONFIG_PAGING_LEVELS == 3 @@ -3222,28 +3253,33 @@ sh_update_linear_entries(struct vcpu *v) if ( shadow_mode_external(d) ) { - /* Install copies of the shadow l3es into the monitor l3 table. - * The monitor l3 table is hooked into slot 0 of the monitor - * l4 table, so we use l3 linear indices 0 to 3 */ + /* Install copies of the shadow l3es into the monitor l2 table + * that maps SH_LINEAR_PT_VIRT_START. */ shadow_l3e_t *sl3e; - l3_pgentry_t *ml3e; - mfn_t l3mfn; + l2_pgentry_t *ml2e; int i; /* Use linear mappings if we can; otherwise make new mappings */ - if ( v == current ) - { - ml3e = __linear_l3_table; - l3mfn = _mfn(l4e_get_pfn(__linear_l4_table[0])); - } + if ( v == current ) + ml2e = __linear_l2_table + + l2_linear_offset(SH_LINEAR_PT_VIRT_START); else { + mfn_t l3mfn, l2mfn; l4_pgentry_t *ml4e; + l3_pgentry_t *ml3e; + int linear_slot = shadow_l4_table_offset(SH_LINEAR_PT_VIRT_START); ml4e = sh_map_domain_page(pagetable_get_mfn(v->arch.monitor_table)); - ASSERT(l4e_get_flags(ml4e[0]) & _PAGE_PRESENT); - l3mfn = _mfn(l4e_get_pfn(ml4e[0])); + + ASSERT(l4e_get_flags(ml4e[linear_slot]) & _PAGE_PRESENT); + l3mfn = _mfn(l4e_get_pfn(ml4e[linear_slot])); ml3e = sh_map_domain_page(l3mfn); sh_unmap_domain_page(ml4e); + + ASSERT(l3e_get_flags(ml3e[0]) & _PAGE_PRESENT); + l2mfn = _mfn(l3e_get_pfn(ml3e[0])); + ml2e = sh_map_domain_page(l2mfn); + sh_unmap_domain_page(ml3e); } /* Shadow l3 tables are made up by sh_update_cr3 */ @@ -3251,15 +3287,15 @@ sh_update_linear_entries(struct vcpu *v) for ( i = 0; i < SHADOW_L3_PAGETABLE_ENTRIES; i++ ) { - ml3e[i] = + ml2e[i] = (shadow_l3e_get_flags(sl3e[i]) & _PAGE_PRESENT) - ? l3e_from_pfn(mfn_x(shadow_l3e_get_mfn(sl3e[i])), + ? l2e_from_pfn(mfn_x(shadow_l3e_get_mfn(sl3e[i])), __PAGE_HYPERVISOR) - : l3e_empty(); + : l2e_empty(); } if ( v != current ) - sh_unmap_domain_page(ml3e); + sh_unmap_domain_page(ml2e); } else domain_crash(d); /* XXX */ @@ -4180,15 +4216,12 @@ sh_x86_emulate_write(struct vcpu *v, unsigned long vaddr, void *src, if ( (vaddr & (bytes - 1)) && !is_hvm_vcpu(v) ) return X86EMUL_UNHANDLEABLE; - shadow_lock(v->domain); addr = emulate_map_dest(v, vaddr, bytes, sh_ctxt); if ( emulate_map_dest_failed(addr) ) - { - shadow_unlock(v->domain); return ((addr == MAPPING_EXCEPTION) ? X86EMUL_EXCEPTION : X86EMUL_UNHANDLEABLE); - } + shadow_lock(v->domain); memcpy(addr, src, bytes); emulate_unmap_dest(v, addr, bytes, sh_ctxt); @@ -4210,16 +4243,12 @@ sh_x86_emulate_cmpxchg(struct vcpu *v, unsigned long vaddr, if ( (vaddr & (bytes - 1)) && !is_hvm_vcpu(v) ) return X86EMUL_UNHANDLEABLE; - shadow_lock(v->domain); - addr = emulate_map_dest(v, vaddr, bytes, sh_ctxt); if ( emulate_map_dest_failed(addr) ) - { - shadow_unlock(v->domain); return ((addr == MAPPING_EXCEPTION) ? X86EMUL_EXCEPTION : X86EMUL_UNHANDLEABLE); - } + shadow_lock(v->domain); switch ( bytes ) { case 1: prev = cmpxchg(((u8 *)addr), old, new); break; @@ -4258,18 +4287,15 @@ sh_x86_emulate_cmpxchg8b(struct vcpu *v, unsigned long vaddr, if ( (vaddr & 7) && !is_hvm_vcpu(v) ) return X86EMUL_UNHANDLEABLE; - shadow_lock(v->domain); - addr = emulate_map_dest(v, vaddr, 8, sh_ctxt); if ( emulate_map_dest_failed(addr) ) - { - shadow_unlock(v->domain); return ((addr == MAPPING_EXCEPTION) ? X86EMUL_EXCEPTION : X86EMUL_UNHANDLEABLE); - } old = (((u64) old_hi) << 32) | (u64) old_lo; new = (((u64) new_hi) << 32) | (u64) new_lo; + + shadow_lock(v->domain); prev = cmpxchg(((u64 *)addr), old, new); if ( prev != old ) |