/* SPDX-License-Identifier: GPL-2.0 */ /*---------------------------------------------------------------------------+ | fpu_system.h | | | | Copyright (C) 1992,1994,1997 | | W. Metzenthen, 22 Parker St, Ormond, Vic 3163, | | Australia. E-mail billm@suburbia.net | | | +---------------------------------------------------------------------------*/ #ifndef _FPU_SYSTEM_H #define _FPU_SYSTEM_H /* system dependent definitions */ #include <linux/sched.h> #include <linux/kernel.h> #include <linux/mm.h> #include <asm/desc.h> #include <asm/mmu_context.h> static inline struct desc_struct FPU_get_ldt_descriptor(unsigned seg) { static struct desc_struct zero_desc; struct desc_struct ret = zero_desc; #ifdef CONFIG_MODIFY_LDT_SYSCALL seg >>= 3; mutex_lock(¤t->mm->context.lock); if (current->mm->context.ldt && seg < current->mm->context.ldt->nr_entries) ret = current->mm->context.ldt->entries[seg]; mutex_unlock(¤t->mm->context.lock); #endif return ret; } #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->limit1 << 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) #define FPU_CS (*(unsigned short *) &(FPU_info->regs->cs)) #define FPU_SS (*(unsigned short *) &(FPU_info->regs->ss)) #define FPU_DS (*(unsigned short *) &(FPU_info->regs->ds)) #define FPU_EAX (FPU_info->regs->ax) #define FPU_EFLAGS (FPU_info->regs->flags) #define FPU_EIP (FPU_info->regs->ip) #define FPU_ORIG_EIP (FPU_info->___orig_eip) #define FPU_lookahead (I387->soft.lookahead) /* nz if ip_offset and cs_selector are not to be set for the current instruction. */ #define no_ip_update (*(u_char *)&(I387->soft.no_update)) #define FPU_rm (*(u_char *)&(I387->soft.rm)) /* Number of bytes of data which can be legally accessed by the current instruction. This only needs to hold a number <= 108, so a byte will do. */ #define access_limit (*(u_char *)&(I387->soft.alimit)) #define partial_status (I387->soft.swd) #define control_word (I387->soft.cwd) #define fpu_tag_word (I387->soft.twd) #define registers (I387->soft.st_space) #define top (I387->soft.ftop) #define instruction_address (*(struct address *)&I387->soft.fip) #define operand_address (*(struct address *)&I387->soft.foo) #define FPU_access_ok(y,z) if ( !access_ok(y,z) ) \ math_abort(FPU_info,SIGSEGV) #define FPU_abort math_abort(FPU_info, SIGSEGV) #define FPU_copy_from_user(to, from, n) \ do { if (copy_from_user(to, from, n)) FPU_abort; } while (0) #undef FPU_IGNORE_CODE_SEGV #ifdef FPU_IGNORE_CODE_SEGV /* access_ok() is very expensive, and causes the emulator to run about 20% slower if applied to the code. Anyway, errors due to bad code addresses should be much rarer than errors due to bad data addresses. */ #define FPU_code_access_ok(z) #else /* A simpler test than access_ok() can probably be done for FPU_code_access_ok() because the only possible error is to step past the upper boundary of a legal code area. */ #define FPU_code_access_ok(z) FPU_access_ok((void __user *)FPU_EIP,z) #endif #define FPU_get_user(x,y) do { if (get_user((x),(y))) FPU_abort; } while (0) #define FPU_put_user(x,y) do { if (put_user((x),(y))) FPU_abort; } while (0) #endif