diff options
| -rw-r--r-- | arch/x86/math-emu/fpu_entry.c | 11 | ||||
| -rw-r--r-- | arch/x86/math-emu/fpu_system.h | 48 | ||||
| -rw-r--r-- | arch/x86/math-emu/get_address.c | 17 |
3 files changed, 51 insertions, 25 deletions
diff --git a/arch/x86/math-emu/fpu_entry.c b/arch/x86/math-emu/fpu_entry.c index 0203baefb5c0..d4a7df2205b8 100644 --- a/arch/x86/math-emu/fpu_entry.c +++ b/arch/x86/math-emu/fpu_entry.c @@ -147,7 +147,7 @@ void math_emulate(struct math_emu_info *info) } code_descriptor = FPU_get_ldt_descriptor(FPU_CS); - if (SEG_D_SIZE(code_descriptor)) { + if (code_descriptor.d) { /* The above test may be wrong, the book is not clear */ /* Segmented 32 bit protected mode */ addr_modes.default_mode = SEG32; @@ -155,11 +155,10 @@ void math_emulate(struct math_emu_info *info) /* 16 bit protected mode */ addr_modes.default_mode = PM16; } - FPU_EIP += code_base = SEG_BASE_ADDR(code_descriptor); - code_limit = code_base - + (SEG_LIMIT(code_descriptor) + - 1) * SEG_GRANULARITY(code_descriptor) - - 1; + FPU_EIP += code_base = seg_get_base(&code_descriptor); + code_limit = seg_get_limit(&code_descriptor) + 1; + code_limit *= seg_get_granularity(&code_descriptor); + code_limit += code_base - 1; if (code_limit < code_base) code_limit = 0xffffffff; } diff --git a/arch/x86/math-emu/fpu_system.h b/arch/x86/math-emu/fpu_system.h index a179254a5122..2319a257ec32 100644 --- a/arch/x86/math-emu/fpu_system.h +++ b/arch/x86/math-emu/fpu_system.h @@ -34,17 +34,43 @@ static inline struct desc_struct FPU_get_ldt_descriptor(unsigned seg) return ret; } -#define SEG_D_SIZE(x) ((x).b & (3 << 21)) -#define SEG_G_BIT(x) ((x).b & (1 << 23)) -#define SEG_GRANULARITY(x) (((x).b & (1 << 23)) ? 4096 : 1) -#define SEG_286_MODE(x) ((x).b & ( 0xff000000 | 0xf0000 | (1 << 23))) -#define SEG_BASE_ADDR(s) (((s).b & 0xff000000) \ - | (((s).b & 0xff) << 16) | ((s).a >> 16)) -#define SEG_LIMIT(s) (((s).b & 0xff0000) | ((s).a & 0xffff)) -#define SEG_EXECUTE_ONLY(s) (((s).b & ((1 << 11) | (1 << 9))) == (1 << 11)) -#define SEG_WRITE_PERM(s) (((s).b & ((1 << 11) | (1 << 9))) == (1 << 9)) -#define SEG_EXPAND_DOWN(s) (((s).b & ((1 << 11) | (1 << 10))) \ - == (1 << 10)) +#define SEG_TYPE_WRITABLE (1U << 1) +#define SEG_TYPE_EXPANDS_DOWN (1U << 2) +#define SEG_TYPE_EXECUTE (1U << 3) +#define SEG_TYPE_EXPAND_MASK (SEG_TYPE_EXPANDS_DOWN | SEG_TYPE_EXECUTE) +#define SEG_TYPE_EXECUTE_MASK (SEG_TYPE_WRITABLE | SEG_TYPE_EXECUTE) + +static inline unsigned long seg_get_base(struct desc_struct *d) +{ + unsigned long base = (unsigned long)d->base2 << 24; + + return base | ((unsigned long)d->base1 << 16) | d->base0; +} + +static inline unsigned long seg_get_limit(struct desc_struct *d) +{ + return ((unsigned long)d->limit << 16) | d->limit0; +} + +static inline unsigned long seg_get_granularity(struct desc_struct *d) +{ + return d->g ? 4096 : 1; +} + +static inline bool seg_expands_down(struct desc_struct *d) +{ + return (d->type & SEG_TYPE_EXPAND_MASK) == SEG_TYPE_EXPANDS_DOWN; +} + +static inline bool seg_execute_only(struct desc_struct *d) +{ + return (d->type & SEG_TYPE_EXECUTE_MASK) == SEG_TYPE_EXECUTE; +} + +static inline bool seg_writable(struct desc_struct *d) +{ + return (d->type & SEG_TYPE_EXECUTE_MASK) == SEG_TYPE_WRITABLE; +} #define I387 (¤t->thread.fpu.state) #define FPU_info (I387->soft.info) diff --git a/arch/x86/math-emu/get_address.c b/arch/x86/math-emu/get_address.c index b8ef9f9d2ffc..c48967c6a0e2 100644 --- a/arch/x86/math-emu/get_address.c +++ b/arch/x86/math-emu/get_address.c @@ -159,17 +159,18 @@ static long pm_address(u_char FPU_modrm, u_char segment, } descriptor = FPU_get_ldt_descriptor(addr->selector); - base_address = SEG_BASE_ADDR(descriptor); + base_address = seg_get_base(&descriptor); address = base_address + offset; - limit = base_address - + (SEG_LIMIT(descriptor) + 1) * SEG_GRANULARITY(descriptor) - 1; + limit = seg_get_limit(&descriptor) + 1; + limit *= seg_get_granularity(&descriptor); + limit += base_address - 1; if (limit < base_address) limit = 0xffffffff; - if (SEG_EXPAND_DOWN(descriptor)) { - if (SEG_G_BIT(descriptor)) + if (seg_expands_down(&descriptor)) { + if (descriptor.g) { seg_top = 0xffffffff; - else { + } else { seg_top = base_address + (1 << 20); if (seg_top < base_address) seg_top = 0xffffffff; @@ -182,8 +183,8 @@ static long pm_address(u_char FPU_modrm, u_char segment, (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))) { + if (seg_execute_only(&descriptor) || + (!seg_writable(&descriptor) && (FPU_modrm & FPU_WRITE_BIT))) { access_limit = 0; } return address; |