| 179 | } |
| 180 | |
| 181 | int |
| 182 | vm86_emulate(struct vm86frame *vmf) |
| 183 | { |
| 184 | struct vm86_kernel *vm86; |
| 185 | caddr_t addr; |
| 186 | u_char i_byte; |
| 187 | u_int temp_flags; |
| 188 | int inc_ip = 1; |
| 189 | int retcode = 0; |
| 190 | |
| 191 | /* |
| 192 | * pcb_ext contains the address of the extension area, or zero if |
| 193 | * the extension is not present. (This check should not be needed, |
| 194 | * as we can't enter vm86 mode until we set up an extension area) |
| 195 | */ |
| 196 | if (curpcb->pcb_ext == 0) |
| 197 | return (SIGBUS); |
| 198 | vm86 = &curpcb->pcb_ext->ext_vm86; |
| 199 | |
| 200 | if (vmf->vmf_eflags & PSL_T) |
| 201 | retcode = SIGTRAP; |
| 202 | |
| 203 | addr = MAKE_ADDR(vmf->vmf_cs, vmf->vmf_ip); |
| 204 | i_byte = vm86_fubyte(addr); |
| 205 | if (i_byte == ADDRESS_SIZE_PREFIX) { |
| 206 | i_byte = vm86_fubyte(++addr); |
| 207 | inc_ip++; |
| 208 | } |
| 209 | |
| 210 | if (vm86->vm86_has_vme) { |
| 211 | switch (i_byte) { |
| 212 | case OPERAND_SIZE_PREFIX: |
| 213 | i_byte = vm86_fubyte(++addr); |
| 214 | inc_ip++; |
| 215 | switch (i_byte) { |
| 216 | case PUSHF: |
| 217 | if (vmf->vmf_eflags & PSL_VIF) |
| 218 | PUSHL((vmf->vmf_eflags & PUSH_MASK) |
| 219 | | PSL_IOPL | PSL_I, vmf); |
| 220 | else |
| 221 | PUSHL((vmf->vmf_eflags & PUSH_MASK) |
| 222 | | PSL_IOPL, vmf); |
| 223 | vmf->vmf_ip += inc_ip; |
| 224 | return (retcode); |
| 225 | |
| 226 | case POPF: |
| 227 | temp_flags = POPL(vmf) & POP_MASK; |
| 228 | vmf->vmf_eflags = (vmf->vmf_eflags & ~POP_MASK) |
| 229 | | temp_flags | PSL_VM | PSL_I; |
| 230 | vmf->vmf_ip += inc_ip; |
| 231 | if (temp_flags & PSL_I) { |
| 232 | vmf->vmf_eflags |= PSL_VIF; |
| 233 | if (vmf->vmf_eflags & PSL_VIP) |
| 234 | break; |
| 235 | } else { |
| 236 | vmf->vmf_eflags &= ~PSL_VIF; |
| 237 | } |
| 238 | return (retcode); |
no test coverage detected