1 #ifndef _LINUX_VM86_H 2 #define _LINUX_VM86_H 3 4 /* 5 * I'm guessing at the VIF/VIP flag usage, but hope that this is how 6 * the Pentium uses them. Linux will return from vm86 mode when both 7 * VIF and VIP is set. 8 * 9 * On a Pentium, we could probably optimize the virtual flags directly 10 * in the eflags register instead of doing it "by hand" in vflags... 11 * 12 * Linus 13 */ 14 15 #define TF_MASK 0x00000100 16 #define IF_MASK 0x00000200 17 #define IOPL_MASK 0x00003000 18 #define NT_MASK 0x00004000 19 #ifdef CONFIG_VM86 20 #define VM_MASK 0x00020000 21 #else 22 #define VM_MASK 0 /* ignored */ 23 #endif 24 #define AC_MASK 0x00040000 25 #define VIF_MASK 0x00080000 /* virtual interrupt flag */ 26 #define VIP_MASK 0x00100000 /* virtual interrupt pending */ 27 #define ID_MASK 0x00200000 28 29 #define BIOSSEG 0x0f000 30 31 #define CPU_086 0 32 #define CPU_186 1 33 #define CPU_286 2 34 #define CPU_386 3 35 #define CPU_486 4 36 #define CPU_586 5 37 38 /* 39 * Return values for the 'vm86()' system call 40 */ 41 #define VM86_TYPE(retval) ((retval) & 0xff) 42 #define VM86_ARG(retval) ((retval) >> 8) 43 44 #define VM86_SIGNAL 0 /* return due to signal */ 45 #define VM86_UNKNOWN 1 /* unhandled GP fault - IO-instruction or similar */ 46 #define VM86_INTx 2 /* int3/int x instruction (ARG = x) */ 47 #define VM86_STI 3 /* sti/popf/iret instruction enabled virtual interrupts */ 48 49 /* 50 * Additional return values when invoking new vm86() 51 */ 52 #define VM86_PICRETURN 4 /* return due to pending PIC request */ 53 #define VM86_TRAP 6 /* return due to DOS-debugger request */ 54 55 /* 56 * function codes when invoking new vm86() 57 */ 58 #define VM86_PLUS_INSTALL_CHECK 0 59 #define VM86_ENTER 1 60 #define VM86_ENTER_NO_BYPASS 2 61 #define VM86_REQUEST_IRQ 3 62 #define VM86_FREE_IRQ 4 63 #define VM86_GET_IRQ_BITS 5 64 #define VM86_GET_AND_RESET_IRQ 6 65 66 /* 67 * This is the stack-layout seen by the user space program when we have 68 * done a translation of "SAVE_ALL" from vm86 mode. The real kernel layout 69 * is 'kernel_vm86_regs' (see below). 70 */ 71 72 struct vm86_regs { 73 /* 74 * normal regs, with special meaning for the segment descriptors.. 75 */ 76 long ebx; 77 long ecx; 78 long edx; 79 long esi; 80 long edi; 81 long ebp; 82 long eax; 83 long __null_ds; 84 long __null_es; 85 long __null_fs; 86 long __null_gs; 87 long orig_eax; 88 long eip; 89 unsigned short cs, __csh; 90 long eflags; 91 long esp; 92 unsigned short ss, __ssh; 93 /* 94 * these are specific to v86 mode: 95 */ 96 unsigned short es, __esh; 97 unsigned short ds, __dsh; 98 unsigned short fs, __fsh; 99 unsigned short gs, __gsh; 100 }; 101 102 struct revectored_struct { 103 unsigned long __map[8]; /* 256 bits */ 104 }; 105 106 struct vm86_struct { 107 struct vm86_regs regs; 108 unsigned long flags; 109 unsigned long screen_bitmap; 110 unsigned long cpu_type; 111 struct revectored_struct int_revectored; 112 struct revectored_struct int21_revectored; 113 }; 114 115 /* 116 * flags masks 117 */ 118 #define VM86_SCREEN_BITMAP 0x0001 119 120 struct vm86plus_info_struct { 121 unsigned long force_return_for_pic:1; 122 unsigned long vm86dbg_active:1; /* for debugger */ 123 unsigned long vm86dbg_TFpendig:1; /* for debugger */ 124 unsigned long unused:28; 125 unsigned long is_vm86pus:1; /* for vm86 internal use */ 126 unsigned char vm86dbg_intxxtab[32]; /* for debugger */ 127 }; 128 129 struct vm86plus_struct { 130 struct vm86_regs regs; 131 unsigned long flags; 132 unsigned long screen_bitmap; 133 unsigned long cpu_type; 134 struct revectored_struct int_revectored; 135 struct revectored_struct int21_revectored; 136 struct vm86plus_info_struct vm86plus; 137 }; 138 139 #ifdef __KERNEL__ 140 /* 141 * This is the (kernel) stack-layout when we have done a "SAVE_ALL" from vm86 142 * mode - the main change is that the old segment descriptors aren't 143 * useful any more and are forced to be zero by the kernel (and the 144 * hardware when a trap occurs), and the real segment descriptors are 145 * at the end of the structure. Look at ptrace.h to see the "normal" 146 * setup. For user space layout see 'struct vm86_regs' above. 147 */ 148 #include <asm/ptrace.h> 149 150 struct kernel_vm86_regs { 151 /* 152 * normal regs, with special meaning for the segment descriptors.. 153 */ 154 struct pt_regs pt; 155 /* 156 * these are specific to v86 mode: 157 */ 158 unsigned short es, __esh; 159 unsigned short ds, __dsh; 160 unsigned short fs, __fsh; 161 unsigned short gs, __gsh; 162 }; 163 164 struct kernel_vm86_struct { 165 struct kernel_vm86_regs regs; 166 /* 167 * the below part remains on the kernel stack while we are in VM86 mode. 168 * 'tss.esp0' then contains the address of VM86_TSS_ESP0 below, and when we 169 * get forced back from VM86, the CPU and "SAVE_ALL" will restore the above 170 * 'struct kernel_vm86_regs' with the then actual values. 171 * Therefore, pt_regs in fact points to a complete 'kernel_vm86_struct' 172 * in kernelspace, hence we need not reget the data from userspace. 173 */ 174 #define VM86_TSS_ESP0 flags 175 unsigned long flags; 176 unsigned long screen_bitmap; 177 unsigned long cpu_type; 178 struct revectored_struct int_revectored; 179 struct revectored_struct int21_revectored; 180 struct vm86plus_info_struct vm86plus; 181 struct pt_regs *regs32; /* here we save the pointer to the old regs */ 182 /* 183 * The below is not part of the structure, but the stack layout continues 184 * this way. In front of 'return-eip' may be some data, depending on 185 * compilation, so we don't rely on this and save the pointer to 'oldregs' 186 * in 'regs32' above. 187 * However, with GCC-2.7.2 and the current CFLAGS you see exactly this: 188 189 long return-eip; from call to vm86() 190 struct pt_regs oldregs; user space registers as saved by syscall 191 */ 192 }; 193 194 #ifdef CONFIG_VM86 195 196 void handle_vm86_fault(struct kernel_vm86_regs *, long); 197 int handle_vm86_trap(struct kernel_vm86_regs *, long, int); 198 199 struct task_struct; 200 void release_vm86_irqs(struct task_struct *); 201 202 #else 203 204 #define handle_vm86_fault(a, b) 205 #define release_vm86_irqs(a) 206 207 static inline int handle_vm86_trap(struct kernel_vm86_regs *a, long b, int c) { 208 return 0; 209 } 210 211 #endif /* CONFIG_VM86 */ 212 213 #endif /* __KERNEL__ */ 214 215 #endif 216
