diff options
Diffstat (limited to 'arch/x86/math-emu/get_address.c')
| -rw-r--r-- | arch/x86/math-emu/get_address.c | 650 |
1 files changed, 308 insertions, 342 deletions
diff --git a/arch/x86/math-emu/get_address.c b/arch/x86/math-emu/get_address.c index 2e2c51a8bd3a..d701e2b39e44 100644 --- a/arch/x86/math-emu/get_address.c +++ b/arch/x86/math-emu/get_address.c @@ -17,7 +17,6 @@ | other processes using the emulator while swapping is in progress. | +---------------------------------------------------------------------------*/ - #include <linux/stddef.h> #include <asm/uaccess.h> @@ -27,31 +26,30 @@ #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) + 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) - }; + 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)) @@ -60,158 +58,141 @@ static int reg_offset_vm86[] = { #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) - }; + 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; -} + 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) +static unsigned long vm86_segment(u_char segment, struct address *addr) { - segment--; + segment--; #ifdef PARANOID - if ( segment > PREFIX_SS_ ) - { - EXCEPTION(EX_INTERNAL|0x130); - math_abort(FPU_info,SIGSEGV); - } + 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; + 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; +{ + struct desc_struct descriptor; + unsigned long base_address, limit, address, seg_top; - segment--; + 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); - } + /* 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; + 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); } - 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; -} + 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 @@ -221,7 +202,6 @@ static long pm_address(u_char FPU_modrm, u_char segment, ..... ......... ......... MOD OPCODE(2) R/M - SIB byte 7 6 5 4 3 2 1 0 @@ -231,208 +211,194 @@ static long pm_address(u_char FPU_modrm, u_char segment, */ void __user *FPU_get_address(u_char FPU_modrm, unsigned long *fpu_eip, - struct address *addr, - fpu_addr_modes addr_modes) + 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 = ®_(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; - 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) - { + 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 == 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; - } + 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; + /* 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; + /* 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); + /* 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; } - 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; -} + add_segment: + address &= 0xffff; -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; + 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); } - 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 ; + + return (void __user *)address; } |
