diff options
Diffstat (limited to 'arch/i386/math-emu/get_address.c')
-rw-r--r-- | arch/i386/math-emu/get_address.c | 438 |
1 files changed, 0 insertions, 438 deletions
diff --git a/arch/i386/math-emu/get_address.c b/arch/i386/math-emu/get_address.c deleted file mode 100644 index 2e2c51a8bd3..00000000000 --- a/arch/i386/math-emu/get_address.c +++ /dev/null @@ -1,438 +0,0 @@ -/*---------------------------------------------------------------------------+ - | get_address.c | - | | - | Get the effective address from an FPU instruction. | - | | - | Copyright (C) 1992,1993,1994,1997 | - | W. Metzenthen, 22 Parker St, Ormond, Vic 3163, | - | Australia. E-mail billm@suburbia.net | - | | - | | - +---------------------------------------------------------------------------*/ - -/*---------------------------------------------------------------------------+ - | Note: | - | The file contains code which accesses user memory. | - | Emulator static data may change when user memory is accessed, due to | - | other processes using the emulator while swapping is in progress. | - +---------------------------------------------------------------------------*/ - - -#include <linux/stddef.h> - -#include <asm/uaccess.h> -#include <asm/desc.h> - -#include "fpu_system.h" -#include "exception.h" -#include "fpu_emu.h" - - -#define FPU_WRITE_BIT 0x10 - -static int reg_offset[] = { - offsetof(struct info,___eax), - offsetof(struct info,___ecx), - offsetof(struct info,___edx), - offsetof(struct info,___ebx), - offsetof(struct info,___esp), - offsetof(struct info,___ebp), - offsetof(struct info,___esi), - offsetof(struct info,___edi) -}; - -#define REG_(x) (*(long *)(reg_offset[(x)]+(u_char *) FPU_info)) - -static int reg_offset_vm86[] = { - offsetof(struct info,___cs), - offsetof(struct info,___vm86_ds), - offsetof(struct info,___vm86_es), - offsetof(struct info,___vm86_fs), - offsetof(struct info,___vm86_gs), - offsetof(struct info,___ss), - offsetof(struct info,___vm86_ds) - }; - -#define VM86_REG_(x) (*(unsigned short *) \ - (reg_offset_vm86[((unsigned)x)]+(u_char *) FPU_info)) - -/* This dummy, gs is not saved on the stack. */ -#define ___GS ___ds - -static int reg_offset_pm[] = { - offsetof(struct info,___cs), - offsetof(struct info,___ds), - offsetof(struct info,___es), - offsetof(struct info,___fs), - offsetof(struct info,___GS), - offsetof(struct info,___ss), - offsetof(struct info,___ds) - }; - -#define PM_REG_(x) (*(unsigned short *) \ - (reg_offset_pm[((unsigned)x)]+(u_char *) FPU_info)) - - -/* Decode the SIB byte. This function assumes mod != 0 */ -static int sib(int mod, unsigned long *fpu_eip) -{ - u_char ss,index,base; - long offset; - - RE_ENTRANT_CHECK_OFF; - FPU_code_access_ok(1); - FPU_get_user(base, (u_char __user *) (*fpu_eip)); /* The SIB byte */ - RE_ENTRANT_CHECK_ON; - (*fpu_eip)++; - ss = base >> 6; - index = (base >> 3) & 7; - base &= 7; - - if ((mod == 0) && (base == 5)) - offset = 0; /* No base register */ - else - offset = REG_(base); - - if (index == 4) - { - /* No index register */ - /* A non-zero ss is illegal */ - if ( ss ) - EXCEPTION(EX_Invalid); - } - else - { - offset += (REG_(index)) << ss; - } - - if (mod == 1) - { - /* 8 bit signed displacement */ - long displacement; - RE_ENTRANT_CHECK_OFF; - FPU_code_access_ok(1); - FPU_get_user(displacement, (signed char __user *) (*fpu_eip)); - offset += displacement; - RE_ENTRANT_CHECK_ON; - (*fpu_eip)++; - } - else if (mod == 2 || base == 5) /* The second condition also has mod==0 */ - { - /* 32 bit displacement */ - long displacement; - RE_ENTRANT_CHECK_OFF; - FPU_code_access_ok(4); - FPU_get_user(displacement, (long __user *) (*fpu_eip)); - offset += displacement; - RE_ENTRANT_CHECK_ON; - (*fpu_eip) += 4; - } - - return offset; -} - - -static unsigned long vm86_segment(u_char segment, - struct address *addr) -{ - segment--; -#ifdef PARANOID - if ( segment > PREFIX_SS_ ) - { - EXCEPTION(EX_INTERNAL|0x130); - math_abort(FPU_info,SIGSEGV); - } -#endif /* PARANOID */ - addr->selector = VM86_REG_(segment); - return (unsigned long)VM86_REG_(segment) << 4; -} - - -/* This should work for 16 and 32 bit protected mode. */ -static long pm_address(u_char FPU_modrm, u_char segment, - struct address *addr, long offset) -{ - struct desc_struct descriptor; - unsigned long base_address, limit, address, seg_top; - - segment--; - -#ifdef PARANOID - /* segment is unsigned, so this also detects if segment was 0: */ - if ( segment > PREFIX_SS_ ) - { - EXCEPTION(EX_INTERNAL|0x132); - math_abort(FPU_info,SIGSEGV); - } -#endif /* PARANOID */ - - switch ( segment ) - { - /* gs isn't used by the kernel, so it still has its - user-space value. */ - case PREFIX_GS_-1: - /* N.B. - movl %seg, mem is a 2 byte write regardless of prefix */ - savesegment(gs, addr->selector); - break; - default: - addr->selector = PM_REG_(segment); - } - - descriptor = LDT_DESCRIPTOR(PM_REG_(segment)); - base_address = SEG_BASE_ADDR(descriptor); - address = base_address + offset; - limit = base_address - + (SEG_LIMIT(descriptor)+1) * SEG_GRANULARITY(descriptor) - 1; - if ( limit < base_address ) limit = 0xffffffff; - - if ( SEG_EXPAND_DOWN(descriptor) ) - { - if ( SEG_G_BIT(descriptor) ) - seg_top = 0xffffffff; - else - { - seg_top = base_address + (1 << 20); - if ( seg_top < base_address ) seg_top = 0xffffffff; - } - access_limit = - (address <= limit) || (address >= seg_top) ? 0 : - ((seg_top-address) >= 255 ? 255 : seg_top-address); - } - else - { - access_limit = - (address > limit) || (address < base_address) ? 0 : - ((limit-address) >= 254 ? 255 : limit-address+1); - } - if ( SEG_EXECUTE_ONLY(descriptor) || - (!SEG_WRITE_PERM(descriptor) && (FPU_modrm & FPU_WRITE_BIT)) ) - { - access_limit = 0; - } - return address; -} - - -/* - MOD R/M byte: MOD == 3 has a special use for the FPU - SIB byte used iff R/M = 100b - - 7 6 5 4 3 2 1 0 - ..... ......... ......... - MOD OPCODE(2) R/M - - - SIB byte - - 7 6 5 4 3 2 1 0 - ..... ......... ......... - SS INDEX BASE - -*/ - -void __user *FPU_get_address(u_char FPU_modrm, unsigned long *fpu_eip, - struct address *addr, - fpu_addr_modes addr_modes) -{ - u_char mod; - unsigned rm = FPU_modrm & 7; - long *cpu_reg_ptr; - int address = 0; /* Initialized just to stop compiler warnings. */ - - /* Memory accessed via the cs selector is write protected - in `non-segmented' 32 bit protected mode. */ - if ( !addr_modes.default_mode && (FPU_modrm & FPU_WRITE_BIT) - && (addr_modes.override.segment == PREFIX_CS_) ) - { - math_abort(FPU_info,SIGSEGV); - } - - addr->selector = FPU_DS; /* Default, for 32 bit non-segmented mode. */ - - mod = (FPU_modrm >> 6) & 3; - - if (rm == 4 && mod != 3) - { - address = sib(mod, fpu_eip); - } - else - { - cpu_reg_ptr = & REG_(rm); - switch (mod) - { - case 0: - if (rm == 5) - { - /* Special case: disp32 */ - RE_ENTRANT_CHECK_OFF; - FPU_code_access_ok(4); - FPU_get_user(address, (unsigned long __user *) (*fpu_eip)); - (*fpu_eip) += 4; - RE_ENTRANT_CHECK_ON; - addr->offset = address; - return (void __user *) address; - } - else - { - address = *cpu_reg_ptr; /* Just return the contents - of the cpu register */ - addr->offset = address; - return (void __user *) address; - } - case 1: - /* 8 bit signed displacement */ - RE_ENTRANT_CHECK_OFF; - FPU_code_access_ok(1); - FPU_get_user(address, (signed char __user *) (*fpu_eip)); - RE_ENTRANT_CHECK_ON; - (*fpu_eip)++; - break; - case 2: - /* 32 bit displacement */ - RE_ENTRANT_CHECK_OFF; - FPU_code_access_ok(4); - FPU_get_user(address, (long __user *) (*fpu_eip)); - (*fpu_eip) += 4; - RE_ENTRANT_CHECK_ON; - break; - case 3: - /* Not legal for the FPU */ - EXCEPTION(EX_Invalid); - } - address += *cpu_reg_ptr; - } - - addr->offset = address; - - switch ( addr_modes.default_mode ) - { - case 0: - break; - case VM86: - address += vm86_segment(addr_modes.override.segment, addr); - break; - case PM16: - case SEG32: - address = pm_address(FPU_modrm, addr_modes.override.segment, - addr, address); - break; - default: - EXCEPTION(EX_INTERNAL|0x133); - } - - return (void __user *)address; -} - - -void __user *FPU_get_address_16(u_char FPU_modrm, unsigned long *fpu_eip, - struct address *addr, - fpu_addr_modes addr_modes) -{ - u_char mod; - unsigned rm = FPU_modrm & 7; - int address = 0; /* Default used for mod == 0 */ - - /* Memory accessed via the cs selector is write protected - in `non-segmented' 32 bit protected mode. */ - if ( !addr_modes.default_mode && (FPU_modrm & FPU_WRITE_BIT) - && (addr_modes.override.segment == PREFIX_CS_) ) - { - math_abort(FPU_info,SIGSEGV); - } - - addr->selector = FPU_DS; /* Default, for 32 bit non-segmented mode. */ - - mod = (FPU_modrm >> 6) & 3; - - switch (mod) - { - case 0: - if (rm == 6) - { - /* Special case: disp16 */ - RE_ENTRANT_CHECK_OFF; - FPU_code_access_ok(2); - FPU_get_user(address, (unsigned short __user *) (*fpu_eip)); - (*fpu_eip) += 2; - RE_ENTRANT_CHECK_ON; - goto add_segment; - } - break; - case 1: - /* 8 bit signed displacement */ - RE_ENTRANT_CHECK_OFF; - FPU_code_access_ok(1); - FPU_get_user(address, (signed char __user *) (*fpu_eip)); - RE_ENTRANT_CHECK_ON; - (*fpu_eip)++; - break; - case 2: - /* 16 bit displacement */ - RE_ENTRANT_CHECK_OFF; - FPU_code_access_ok(2); - FPU_get_user(address, (unsigned short __user *) (*fpu_eip)); - (*fpu_eip) += 2; - RE_ENTRANT_CHECK_ON; - break; - case 3: - /* Not legal for the FPU */ - EXCEPTION(EX_Invalid); - break; - } - switch ( rm ) - { - case 0: - address += FPU_info->___ebx + FPU_info->___esi; - break; - case 1: - address += FPU_info->___ebx + FPU_info->___edi; - break; - case 2: - address += FPU_info->___ebp + FPU_info->___esi; - if ( addr_modes.override.segment == PREFIX_DEFAULT ) - addr_modes.override.segment = PREFIX_SS_; - break; - case 3: - address += FPU_info->___ebp + FPU_info->___edi; - if ( addr_modes.override.segment == PREFIX_DEFAULT ) - addr_modes.override.segment = PREFIX_SS_; - break; - case 4: - address += FPU_info->___esi; - break; - case 5: - address += FPU_info->___edi; - break; - case 6: - address += FPU_info->___ebp; - if ( addr_modes.override.segment == PREFIX_DEFAULT ) - addr_modes.override.segment = PREFIX_SS_; - break; - case 7: - address += FPU_info->___ebx; - break; - } - - add_segment: - address &= 0xffff; - - addr->offset = address; - - switch ( addr_modes.default_mode ) - { - case 0: - break; - case VM86: - address += vm86_segment(addr_modes.override.segment, addr); - break; - case PM16: - case SEG32: - address = pm_address(FPU_modrm, addr_modes.override.segment, - addr, address); - break; - default: - EXCEPTION(EX_INTERNAL|0x131); - } - - return (void __user *)address ; -} |