/arch/x86/include/asm/syscall.h
https://bitbucket.org/ndreys/linux-sunxi · C++ Header · 215 lines · 175 code · 16 blank · 24 comment · 35 complexity · 744f57efa6977edbcc85e42da1e99478 MD5 · raw file
- /*
- * Access to user system call parameters and results
- *
- * Copyright (C) 2008-2009 Red Hat, Inc. All rights reserved.
- *
- * This copyrighted material is made available to anyone wishing to use,
- * modify, copy, or redistribute it subject to the terms and conditions
- * of the GNU General Public License v.2.
- *
- * See asm-generic/syscall.h for descriptions of what we must do here.
- */
- #ifndef _ASM_X86_SYSCALL_H
- #define _ASM_X86_SYSCALL_H
- #include <linux/sched.h>
- #include <linux/err.h>
- extern const unsigned long sys_call_table[];
- /*
- * Only the low 32 bits of orig_ax are meaningful, so we return int.
- * This importantly ignores the high bits on 64-bit, so comparisons
- * sign-extend the low 32 bits.
- */
- static inline int syscall_get_nr(struct task_struct *task, struct pt_regs *regs)
- {
- return regs->orig_ax;
- }
- static inline void syscall_rollback(struct task_struct *task,
- struct pt_regs *regs)
- {
- regs->ax = regs->orig_ax;
- }
- static inline long syscall_get_error(struct task_struct *task,
- struct pt_regs *regs)
- {
- unsigned long error = regs->ax;
- #ifdef CONFIG_IA32_EMULATION
- /*
- * TS_COMPAT is set for 32-bit syscall entries and then
- * remains set until we return to user mode.
- */
- if (task_thread_info(task)->status & TS_COMPAT)
- /*
- * Sign-extend the value so (int)-EFOO becomes (long)-EFOO
- * and will match correctly in comparisons.
- */
- error = (long) (int) error;
- #endif
- return IS_ERR_VALUE(error) ? error : 0;
- }
- static inline long syscall_get_return_value(struct task_struct *task,
- struct pt_regs *regs)
- {
- return regs->ax;
- }
- static inline void syscall_set_return_value(struct task_struct *task,
- struct pt_regs *regs,
- int error, long val)
- {
- regs->ax = (long) error ?: val;
- }
- #ifdef CONFIG_X86_32
- static inline void syscall_get_arguments(struct task_struct *task,
- struct pt_regs *regs,
- unsigned int i, unsigned int n,
- unsigned long *args)
- {
- BUG_ON(i + n > 6);
- memcpy(args, ®s->bx + i, n * sizeof(args[0]));
- }
- static inline void syscall_set_arguments(struct task_struct *task,
- struct pt_regs *regs,
- unsigned int i, unsigned int n,
- const unsigned long *args)
- {
- BUG_ON(i + n > 6);
- memcpy(®s->bx + i, args, n * sizeof(args[0]));
- }
- #else /* CONFIG_X86_64 */
- static inline void syscall_get_arguments(struct task_struct *task,
- struct pt_regs *regs,
- unsigned int i, unsigned int n,
- unsigned long *args)
- {
- # ifdef CONFIG_IA32_EMULATION
- if (task_thread_info(task)->status & TS_COMPAT)
- switch (i) {
- case 0:
- if (!n--) break;
- *args++ = regs->bx;
- case 1:
- if (!n--) break;
- *args++ = regs->cx;
- case 2:
- if (!n--) break;
- *args++ = regs->dx;
- case 3:
- if (!n--) break;
- *args++ = regs->si;
- case 4:
- if (!n--) break;
- *args++ = regs->di;
- case 5:
- if (!n--) break;
- *args++ = regs->bp;
- case 6:
- if (!n--) break;
- default:
- BUG();
- break;
- }
- else
- # endif
- switch (i) {
- case 0:
- if (!n--) break;
- *args++ = regs->di;
- case 1:
- if (!n--) break;
- *args++ = regs->si;
- case 2:
- if (!n--) break;
- *args++ = regs->dx;
- case 3:
- if (!n--) break;
- *args++ = regs->r10;
- case 4:
- if (!n--) break;
- *args++ = regs->r8;
- case 5:
- if (!n--) break;
- *args++ = regs->r9;
- case 6:
- if (!n--) break;
- default:
- BUG();
- break;
- }
- }
- static inline void syscall_set_arguments(struct task_struct *task,
- struct pt_regs *regs,
- unsigned int i, unsigned int n,
- const unsigned long *args)
- {
- # ifdef CONFIG_IA32_EMULATION
- if (task_thread_info(task)->status & TS_COMPAT)
- switch (i) {
- case 0:
- if (!n--) break;
- regs->bx = *args++;
- case 1:
- if (!n--) break;
- regs->cx = *args++;
- case 2:
- if (!n--) break;
- regs->dx = *args++;
- case 3:
- if (!n--) break;
- regs->si = *args++;
- case 4:
- if (!n--) break;
- regs->di = *args++;
- case 5:
- if (!n--) break;
- regs->bp = *args++;
- case 6:
- if (!n--) break;
- default:
- BUG();
- break;
- }
- else
- # endif
- switch (i) {
- case 0:
- if (!n--) break;
- regs->di = *args++;
- case 1:
- if (!n--) break;
- regs->si = *args++;
- case 2:
- if (!n--) break;
- regs->dx = *args++;
- case 3:
- if (!n--) break;
- regs->r10 = *args++;
- case 4:
- if (!n--) break;
- regs->r8 = *args++;
- case 5:
- if (!n--) break;
- regs->r9 = *args++;
- case 6:
- if (!n--) break;
- default:
- BUG();
- break;
- }
- }
- #endif /* CONFIG_X86_32 */
- #endif /* _ASM_X86_SYSCALL_H */