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Diffstat (limited to 'arch/i386/math-emu/get_address.c')
-rw-r--r--arch/i386/math-emu/get_address.c438
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 ;
-}
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