[mirror_ubuntu-bionic-kernel.git] / arch / x86 / math-emu / fpu_system.h

/*---------------------------------------------------------------------------+
 |  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(&current->mm->context.lock);
	if (current->mm->context.ldt && seg < current->mm->context.ldt->nr_entries)
		ret = current->mm->context.ldt->entries[seg];
	mutex_unlock(&current->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			(&current->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(x,y,z)	if ( !access_ok(x,y,z) ) \
				math_abort(FPU_info,SIGSEGV)
#define FPU_abort		math_abort(FPU_info, SIGSEGV)

#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(VERIFY_READ,(void __user *)FPU_EIP,z)
#endif

#define FPU_get_user(x,y)       get_user((x),(y))
#define FPU_put_user(x,y)       put_user((x),(y))

#endif
Commit	Line	Data
1da177e4 LT	1	/*---------------------------------------------------------------------------+
	2	\| fpu_system.h \|
	3	\| \|
	4	\| Copyright (C) 1992,1994,1997 \|
	5	\| W. Metzenthen, 22 Parker St, Ormond, Vic 3163, \|
	6	\| Australia. E-mail billm@suburbia.net \|
	7	\| \|
	8	+---------------------------------------------------------------------------*/
	9
	10	#ifndef _FPU_SYSTEM_H
	11	#define _FPU_SYSTEM_H
	12
	13	/* system dependent definitions */
	14
	15	#include <linux/sched.h>
	16	#include <linux/kernel.h>
	17	#include <linux/mm.h>
	18
4809146b JG	19	#include <asm/desc.h>
	20	#include <asm/mmu_context.h>
	21
	22	static inline struct desc_struct FPU_get_ldt_descriptor(unsigned seg)
	23	{
	24	static struct desc_struct zero_desc;
	25	struct desc_struct ret = zero_desc;
	26
	27	#ifdef CONFIG_MODIFY_LDT_SYSCALL
	28	seg >>= 3;
	29	mutex_lock(&current->mm->context.lock);
bbf79d21	30	if (current->mm->context.ldt && seg < current->mm->context.ldt->nr_entries)
4809146b JG	31	ret = current->mm->context.ldt->entries[seg];
	32	mutex_unlock(&current->mm->context.lock);
	33	#endif
	34	return ret;
	35	}
	36
718f5d00 TG	37	#define SEG_TYPE_WRITABLE (1U << 1)
	38	#define SEG_TYPE_EXPANDS_DOWN (1U << 2)
	39	#define SEG_TYPE_EXECUTE (1U << 3)
	40	#define SEG_TYPE_EXPAND_MASK (SEG_TYPE_EXPANDS_DOWN \| SEG_TYPE_EXECUTE)
	41	#define SEG_TYPE_EXECUTE_MASK (SEG_TYPE_WRITABLE \| SEG_TYPE_EXECUTE)
	42
	43	static inline unsigned long seg_get_base(struct desc_struct *d)
	44	{
	45	unsigned long base = (unsigned long)d->base2 << 24;
	46
	47	return base \| ((unsigned long)d->base1 << 16) \| d->base0;
	48	}
	49
	50	static inline unsigned long seg_get_limit(struct desc_struct *d)
	51	{
38e9e81f	52	return ((unsigned long)d->limit1 << 16) \| d->limit0;
718f5d00 TG	53	}
	54
	55	static inline unsigned long seg_get_granularity(struct desc_struct *d)
	56	{
	57	return d->g ? 4096 : 1;
	58	}
	59
	60	static inline bool seg_expands_down(struct desc_struct *d)
	61	{
	62	return (d->type & SEG_TYPE_EXPAND_MASK) == SEG_TYPE_EXPANDS_DOWN;
	63	}
	64
	65	static inline bool seg_execute_only(struct desc_struct *d)
	66	{
	67	return (d->type & SEG_TYPE_EXECUTE_MASK) == SEG_TYPE_EXECUTE;
	68	}
	69
	70	static inline bool seg_writable(struct desc_struct *d)
	71	{
	72	return (d->type & SEG_TYPE_EXECUTE_MASK) == SEG_TYPE_WRITABLE;
	73	}
1da177e4	74
7366ed77	75	#define I387 (&current->thread.fpu.state)
61c4628b	76	#define FPU_info (I387->soft.info)
1da177e4	77
d315760f TH	78	#define FPU_CS ((unsigned short ) &(FPU_info->regs->cs))
	79	#define FPU_SS ((unsigned short ) &(FPU_info->regs->ss))
	80	#define FPU_DS ((unsigned short ) &(FPU_info->regs->ds))
	81	#define FPU_EAX (FPU_info->regs->ax)
	82	#define FPU_EFLAGS (FPU_info->regs->flags)
	83	#define FPU_EIP (FPU_info->regs->ip)
1da177e4 LT	84	#define FPU_ORIG_EIP (FPU_info->___orig_eip)
1da177e4 LT	85
61c4628b	86	#define FPU_lookahead (I387->soft.lookahead)
1da177e4 LT	87
	88	/* nz if ip_offset and cs_selector are not to be set for the current
	89	instruction. */
61c4628b SS	90	#define no_ip_update ((u_char )&(I387->soft.no_update))
61c4628b SS	91	#define FPU_rm ((u_char )&(I387->soft.rm))
1da177e4 LT	92
	93	/* Number of bytes of data which can be legally accessed by the current
	94	instruction. This only needs to hold a number <= 108, so a byte will do. */
61c4628b	95	#define access_limit ((u_char )&(I387->soft.alimit))
1da177e4	96
61c4628b SS	97	#define partial_status (I387->soft.swd)
	98	#define control_word (I387->soft.cwd)
	99	#define fpu_tag_word (I387->soft.twd)
	100	#define registers (I387->soft.st_space)
	101	#define top (I387->soft.ftop)
1da177e4	102
61c4628b SS	103	#define instruction_address ((struct address )&I387->soft.fip)
61c4628b SS	104	#define operand_address ((struct address )&I387->soft.foo)
1da177e4 LT	105
	106	#define FPU_access_ok(x,y,z) if ( !access_ok(x,y,z) ) \
	107	math_abort(FPU_info,SIGSEGV)
d606f88f	108	#define FPU_abort math_abort(FPU_info, SIGSEGV)
1da177e4 LT	109
	110	#undef FPU_IGNORE_CODE_SEGV
	111	#ifdef FPU_IGNORE_CODE_SEGV
	112	/* access_ok() is very expensive, and causes the emulator to run
	113	about 20% slower if applied to the code. Anyway, errors due to bad
	114	code addresses should be much rarer than errors due to bad data
	115	addresses. */
	116	#define FPU_code_access_ok(z)
	117	#else
	118	/* A simpler test than access_ok() can probably be done for
	119	FPU_code_access_ok() because the only possible error is to step
	120	past the upper boundary of a legal code area. */
	121	#define FPU_code_access_ok(z) FPU_access_ok(VERIFY_READ,(void __user *)FPU_EIP,z)
	122	#endif
	123
	124	#define FPU_get_user(x,y) get_user((x),(y))
	125	#define FPU_put_user(x,y) put_user((x),(y))
	126
	127	#endif