From: Jack Lange Date: Thu, 30 Oct 2008 05:30:57 +0000 (-0500) Subject: unified and simplified the control register handlers to operate in all CPU modes X-Git-Url: http://v3vee.org/palacios/gitweb/gitweb.cgi?p=palacios.git;a=commitdiff_plain;h=207e3b36648e4019ad8505c75ae6ef0778464a26 unified and simplified the control register handlers to operate in all CPU modes --- diff --git a/palacios/include/palacios/vmm_types.h b/palacios/include/palacios/vmm_types.h index fd13ab7..1c2f958 100644 --- a/palacios/include/palacios/vmm_types.h +++ b/palacios/include/palacios/vmm_types.h @@ -23,6 +23,9 @@ #ifdef __V3VEE__ #include + + + typedef enum {SHADOW_PAGING, NESTED_PAGING} v3_paging_mode_t; typedef enum {VM_RUNNING, VM_STOPPED, VM_SUSPENDED, VM_ERROR, VM_EMULATING} v3_vm_operating_mode_t; @@ -32,8 +35,6 @@ typedef enum {PHYSICAL_MEM, VIRTUAL_MEM} v3_vm_mem_mode_t; - - typedef signed char schar_t; typedef unsigned char uchar_t; diff --git a/palacios/src/palacios/vm_guest.c b/palacios/src/palacios/vm_guest.c index 5666fef..614c6a5 100644 --- a/palacios/src/palacios/vm_guest.c +++ b/palacios/src/palacios/vm_guest.c @@ -56,6 +56,33 @@ v3_vm_cpu_mode_t v3_get_cpu_mode(struct guest_info * info) { } } + +static const uchar_t REAL_STR[] = "Real"; +static const uchar_t PROTECTED_STR[] = "Protected"; +static const uchar_t PROTECTED_PAE_STR[] = "Protected+PAE"; +static const uchar_t LONG_STR[] = "Long"; +static const uchar_t LONG_32_COMPAT_STR[] = "32bit Compat"; +static const uchar_t LONG_16_COMPAT_STR[] = "16bit Compat"; + +const uchar_t * v3_cpu_mode_to_str(v3_vm_cpu_mode_t mode) { + switch (mode) { + case REAL: + return REAL_STR; + case PROTECTED: + return PROTECTED_STR; + case PROTECTED_PAE: + return PROTECTED_PAE_STR; + case LONG: + return LONG_STR; + case LONG_32_COMPAT: + return LONG_32_COMPAT_STR; + case LONG_16_COMPAT: + return LONG_16_COMPAT_STR; + default: + return NULL; + } +} + v3_vm_mem_mode_t v3_get_mem_mode(struct guest_info * info) { struct cr0_32 * cr0; @@ -69,8 +96,6 @@ v3_vm_mem_mode_t v3_get_mem_mode(struct guest_info * info) { return -1; } - - if (cr0->pg == 0) { return PHYSICAL_MEM; } else { @@ -78,6 +103,20 @@ v3_vm_mem_mode_t v3_get_mem_mode(struct guest_info * info) { } } +static const uchar_t PHYS_MEM_STR[] = "Physical Memory"; +static const uchar_t VIRT_MEM_STR[] = "Virtual Memory"; + +const uchar_t * v3_mem_mode_to_str(v3_vm_mem_mode_t mode) { + switch (mode) { + case PHYSICAL_MEM: + return PHYS_MEM_STR; + case VIRTUAL_MEM: + return VIRT_MEM_STR; + default: + return NULL; + } +} + void v3_print_segments(struct guest_info * info) { struct v3_segments * segs = &(info->segments); diff --git a/palacios/src/palacios/vmm_ctrl_regs.c b/palacios/src/palacios/vmm_ctrl_regs.c index 4cb40d8..894bfc2 100644 --- a/palacios/src/palacios/vmm_ctrl_regs.c +++ b/palacios/src/palacios/vmm_ctrl_regs.c @@ -41,19 +41,7 @@ static int handle_lmsw(struct guest_info * info, struct x86_instr * dec_instr); static int handle_clts(struct guest_info * info, struct x86_instr * dec_instr); - static int handle_mov_to_cr0(struct guest_info * info, struct x86_instr * dec_instr); -static int handle_mov_to_cr0_32(struct guest_info * info, struct x86_instr * dec_instr); -static int handle_mov_to_cr0_32pae(struct guest_info * info, struct x86_instr * dec_instr); -static int handle_mov_to_cr0_64(struct guest_info * info, struct x86_instr * dec_instr); -static int handle_mov_to_cr0_64compat(struct guest_info * info, struct x86_instr * dec_instr); - -static int handle_mov_to_cr3_32(struct guest_info * info, struct x86_instr * dec_instr); -static int handle_mov_to_cr3_32pae(struct guest_info * info, struct x86_instr * dec_instr); -static int handle_mov_to_cr3_64(struct guest_info * info, struct x86_instr * dec_instr); -static int handle_mov_to_cr3_64compat(struct guest_info * info, struct x86_instr * dec_instr); - - // First Attempt = 494 lines @@ -69,8 +57,6 @@ int v3_handle_cr0_write(struct guest_info * info) { ret = read_guest_va_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr); } - - if (v3_decode(info, (addr_t)instr, &dec_instr) == -1) { PrintError("Could not decode instruction\n"); return -1; @@ -107,53 +93,29 @@ int v3_handle_cr0_write(struct guest_info * info) { +// The CR0 register only has flags in the low 32 bits +// The hardware does a format check to make sure the high bits are zero +// Because of this we can ignore the high 32 bits here static int handle_mov_to_cr0(struct guest_info * info, struct x86_instr * dec_instr) { - PrintDebug("MOV2CR0\n"); - - switch (info->cpu_mode) { - case REAL: - case PROTECTED: - return handle_mov_to_cr0_32(info, dec_instr); - case PROTECTED_PAE: - return handle_mov_to_cr0_32pae(info, dec_instr); - case LONG: - return handle_mov_to_cr0_64(info, dec_instr); - case LONG_32_COMPAT: - return handle_mov_to_cr0_64compat(info, dec_instr); - default: - PrintError("Invalid CPU Operating Mode: %d\n", info->cpu_mode); - return -1; - - } -} - -static int handle_mov_to_cr0_32pae(struct guest_info * info, struct x86_instr * dec_instr) { - PrintError("32 bit PAE mov to CR0 not implemented\n"); - return -1; -} - -static int handle_mov_to_cr0_64(struct guest_info * info, struct x86_instr * dec_instr) { - PrintError("64 bit mov to CR0 not implemented\n"); - return -1; -} - -static int handle_mov_to_cr0_64compat(struct guest_info * info, struct x86_instr * dec_instr) { - PrintError("64 bit compatibility mode move to CR0 not implemented\n"); - return -1; -} - - -static int handle_mov_to_cr0_32(struct guest_info * info, struct x86_instr * dec_instr) { // 32 bit registers struct cr0_32 * shadow_cr0 = (struct cr0_32 *)&(info->ctrl_regs.cr0); struct cr0_32 * new_cr0 = (struct cr0_32 *)(dec_instr->src_operand.operand); struct cr0_32 * guest_cr0 = (struct cr0_32 *)&(info->shdw_pg_state.guest_cr0); + uint_t paging_transition = 0; + + PrintDebug("MOV2CR0 (MODE=%s)\n", v3_cpu_mode_to_str(info->cpu_mode)); PrintDebug("OperandVal = %x, length=%d\n", *(uint_t *)new_cr0, dec_instr->src_operand.size); PrintDebug("Old CR0=%x\n", *(uint_t *)shadow_cr0); PrintDebug("Old Guest CR0=%x\n", *(uint_t *)guest_cr0); + + // We detect if this is a paging transition + if (guest_cr0->pg != new_cr0->pg) { + paging_transition = 1; + } + // Guest always sees the value they wrote *guest_cr0 = *new_cr0; @@ -162,31 +124,33 @@ static int handle_mov_to_cr0_32(struct guest_info * info, struct x86_instr * dec // Set the shadow register to catch non-virtualized flags *shadow_cr0 = *guest_cr0; - - if (v3_get_mem_mode(info) == VIRTUAL_MEM) { - /* struct cr3_32 * guest_cr3 = (struct cr3_32 *)&(info->shdw_pg_state.guest_cr3); - info->ctrl_regs.cr3 = *(addr_t*)guest_cr3; - */ - PrintDebug("Activating Shadow Page Tables\n"); + // Paging is always enabled + shadow_cr0->pg = 1; - if (v3_activate_shadow_pt(info) == -1) { - PrintError("Failed to activate shadow page tables\n"); - return -1; - } - } else { + // Was there a paging transition + // Meaning we need to change the page tables + if (paging_transition) { + if (v3_get_mem_mode(info) == VIRTUAL_MEM) { - if (v3_activate_passthrough_pt(info) == -1) { - PrintError("Failed to activate passthrough page tables\n"); - return -1; + PrintDebug("Activating Shadow Page Tables\n"); + + if (v3_activate_shadow_pt(info) == -1) { + PrintError("Failed to activate shadow page tables\n"); + return -1; + } + } else { + + if (v3_activate_passthrough_pt(info) == -1) { + PrintError("Failed to activate passthrough page tables\n"); + return -1; + } } - shadow_cr0->pg = 1; } - - PrintDebug("New Guest CR0=%x\n",*(uint_t *)guest_cr0); - + + PrintDebug("New Guest CR0=%x\n",*(uint_t *)guest_cr0); PrintDebug("New CR0=%x\n", *(uint_t *)shadow_cr0); - + return 0; } @@ -265,7 +229,7 @@ int v3_handle_cr0_read(struct guest_info * info) { struct cr0_32 * dst_reg = (struct cr0_32 *)(dec_instr.dst_operand.operand); struct cr0_32 * shadow_cr0 = (struct cr0_32 *)&(info->ctrl_regs.cr0); - PrintDebug("MOVCR2\n"); + PrintDebug("MOVCR2 (mode=%s)\n", info->cpu_mode); if (info->shdw_pg_mode == SHADOW_PAGING) { struct cr0_32 * guest_cr0 = (struct cr0_32 *)&(info->shdw_pg_state.guest_cr0); @@ -320,11 +284,15 @@ int v3_handle_cr3_write(struct guest_info * info) { } if (v3_opcode_cmp(V3_OPCODE_MOV2CR, (const uchar_t *)(dec_instr.opcode)) == 0) { - PrintDebug("MOV2CR3\n"); - - if (info->mem_mode == PHYSICAL_MEM) { - // All we do is update the guest CR3 + PrintDebug("MOV2CR3 (cpu_mode=%s)\n", v3_cpu_mode_to_str(info->cpu_mode)); + if (info->shdw_pg_mode == SHADOW_PAGING) { + PrintDebug("Old Shadow CR3=%p; Old Guest CR3=%p\n", + (void *)(addr_t)(info->ctrl_regs.cr3), + (void*)(addr_t)(info->shdw_pg_state.guest_cr3)); + + + // We update the guest CR3 if (info->cpu_mode == LONG) { struct cr3_64 * new_cr3 = (struct cr3_64 *)(dec_instr.src_operand.operand); struct cr3_64 * guest_cr3 = (struct cr3_64 *)&(info->shdw_pg_state.guest_cr3); @@ -334,34 +302,32 @@ int v3_handle_cr3_write(struct guest_info * info) { struct cr3_32 * guest_cr3 = (struct cr3_32 *)&(info->shdw_pg_state.guest_cr3); *guest_cr3 = *new_cr3; } - - } else { - - switch (info->cpu_mode) { - case PROTECTED: - if (handle_mov_to_cr3_32(info, &dec_instr) == -1) { - return -1; - } - break; - case PROTECTED_PAE: - if (handle_mov_to_cr3_32pae(info, &dec_instr) == -1) { - return -1; - } - break; - case LONG: - if (handle_mov_to_cr3_64(info, &dec_instr) == -1) { - return -1; - } - break; - case LONG_32_COMPAT: - if (handle_mov_to_cr3_64compat(info, &dec_instr) == -1) { + + // If Paging is enabled in the guest then we need to change the shadow page tables + if (info->mem_mode == VIRTUAL_MEM) { + if (v3_activate_shadow_pt(info) == -1) { + PrintError("Failed to activate 32 bit shadow page table\n"); return -1; } - break; - default: - PrintError("Unhandled CPU mode: %d\n", info->cpu_mode); - return -1; + } + + PrintDebug("New Shadow CR3=%p; New Guest CR3=%p\n", + (void *)(addr_t)(info->ctrl_regs.cr3), + (void*)(addr_t)(info->shdw_pg_state.guest_cr3)); + + } else if (info->shdw_pg_mode == NESTED_PAGING) { + + // This is just a passthrough operation which we probably don't need here + if (info->cpu_mode == LONG) { + struct cr3_64 * new_cr3 = (struct cr3_64 *)(dec_instr.src_operand.operand); + struct cr3_64 * guest_cr3 = (struct cr3_64 *)&(info->ctrl_regs.cr3); + *guest_cr3 = *new_cr3; + } else { + struct cr3_32 * new_cr3 = (struct cr3_32 *)(dec_instr.src_operand.operand); + struct cr3_32 * guest_cr3 = (struct cr3_32 *)&(info->ctrl_regs.cr3); + *guest_cr3 = *new_cr3; } + } } else { PrintError("Unhandled opcode in handle_cr3_write\n"); @@ -375,56 +341,6 @@ int v3_handle_cr3_write(struct guest_info * info) { - - - - -static int handle_mov_to_cr3_32(struct guest_info * info, struct x86_instr * dec_instr) { - PrintDebug("CR3 at 0x%p\n", &(info->ctrl_regs.cr3)); - - if (info->shdw_pg_mode == SHADOW_PAGING) { - struct cr3_32 * new_cr3 = (struct cr3_32 *)(dec_instr->src_operand.operand); - struct cr3_32 * guest_cr3 = (struct cr3_32 *)&(info->shdw_pg_state.guest_cr3); -#ifdef DEBUG_CTRL_REGS - struct cr3_32 * shadow_cr3 = (struct cr3_32 *)&(info->ctrl_regs.cr3); -#endif - - PrintDebug("Old Shadow CR3=%x; Old Guest CR3=%x\n", - *(uint_t*)shadow_cr3, *(uint_t*)guest_cr3); - - - // Store the write value to virtualize CR3 - *guest_cr3 = *new_cr3; - - if (v3_activate_shadow_pt(info) == -1) { - PrintError("Failed to activate 32 bit shadow page table\n"); - return -1; - } - - PrintDebug("New Shadow CR3=%x; New Guest CR3=%x\n", - *(uint_t*)shadow_cr3, *(uint_t*)guest_cr3); - } - return 0; -} - - -static int handle_mov_to_cr3_32pae(struct guest_info * info, struct x86_instr * dec_instr) { - PrintError("32 Bit PAE mode Mov to CR3 not implemented\n"); - return -1; -} - -static int handle_mov_to_cr3_64(struct guest_info * info, struct x86_instr * dec_instr) { - PrintError("Long mode Mov to CR3 not implemented\n"); - return -1; -} - -static int handle_mov_to_cr3_64compat(struct guest_info * info, struct x86_instr * dec_instr) { - PrintError("Long compatiblity mode move to CR3 not implemented\n"); - return -1; -} - - - // first attempt = 156 lines // current = 36 lines int v3_handle_cr3_read(struct guest_info * info) { @@ -438,24 +354,40 @@ int v3_handle_cr3_read(struct guest_info * info) { ret = read_guest_va_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr); } - - if (v3_decode(info, (addr_t)instr, &dec_instr) == -1) { PrintError("Could not decode instruction\n"); return -1; } if (v3_opcode_cmp(V3_OPCODE_MOVCR2, (const uchar_t *)(dec_instr.opcode)) == 0) { - PrintDebug("MOVCR32\n"); - struct cr3_32 * dst_reg = (struct cr3_32 *)(dec_instr.dst_operand.operand); - - PrintDebug("CR3 at 0x%p\n", &(info->ctrl_regs.cr3)); + PrintDebug("MOVCR32 (mode=%s)\n", v3_cpu_mode_to_str(info->cpu_mode)); if (info->shdw_pg_mode == SHADOW_PAGING) { - *dst_reg = *(struct cr3_32 *)&(info->shdw_pg_state.guest_cr3); - } else { - *dst_reg = *(struct cr3_32 *)&(info->ctrl_regs.cr3); + + if (info->cpu_mode == LONG) { + struct cr3_64 * dst_reg = (struct cr3_64 *)(dec_instr.dst_operand.operand); + struct cr3_64 * guest_cr3 = (struct cr3_64 *)&(info->shdw_pg_state.guest_cr3); + *dst_reg = *guest_cr3; + } else { + struct cr3_32 * dst_reg = (struct cr3_32 *)(dec_instr.dst_operand.operand); + struct cr3_32 * guest_cr3 = (struct cr3_32 *)&(info->shdw_pg_state.guest_cr3); + *dst_reg = *guest_cr3; + } + + } else if (info->shdw_pg_mode == NESTED_PAGING) { + + // This is just a passthrough operation which we probably don't need here + if (info->cpu_mode == LONG) { + struct cr3_64 * dst_reg = (struct cr3_64 *)(dec_instr.dst_operand.operand); + struct cr3_64 * guest_cr3 = (struct cr3_64 *)&(info->ctrl_regs.cr3); + *dst_reg = *guest_cr3; + } else { + struct cr3_32 * dst_reg = (struct cr3_32 *)(dec_instr.dst_operand.operand); + struct cr3_32 * guest_cr3 = (struct cr3_32 *)&(info->ctrl_regs.cr3); + *dst_reg = *guest_cr3; + } } + } else { PrintError("Unhandled opcode in handle_cr3_read\n"); return -1;