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-rw-r--r--arch/x86/math-emu/fpu_system.h130
1 files changed, 130 insertions, 0 deletions
diff --git a/arch/x86/math-emu/fpu_system.h b/arch/x86/math-emu/fpu_system.h
new file mode 100644
index 000000000..eec3e4805
--- /dev/null
+++ b/arch/x86/math-emu/fpu_system.h
@@ -0,0 +1,130 @@
+/* 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(&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.fpstate->regs)
+#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