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-rw-r--r--arch/x86/include/asm/syscall.h213
1 files changed, 213 insertions, 0 deletions
diff --git a/arch/x86/include/asm/syscall.h b/arch/x86/include/asm/syscall.h
new file mode 100644
index 000000000000..d82f39bb7905
--- /dev/null
+++ b/arch/x86/include/asm/syscall.h
@@ -0,0 +1,213 @@
+/*
+ * Access to user system call parameters and results
+ *
+ * Copyright (C) 2008 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>
+
+static inline long syscall_get_nr(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ /*
+ * We always sign-extend a -1 value being set here,
+ * so this is always either -1L or a syscall number.
+ */
+ 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, &regs->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(&regs->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 */