x86, um: ... and asm-x86 move

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

1 files changed, 211 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..04c47dc5597c
--- /dev/null
+++ b/arch/x86/include/asm/syscall.h
@@ -0,0 +1,211 @@
+/*
+ * 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_SYSCALL_H
+#define _ASM_SYSCALL_H	1
+
+#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 + n) {
+		case 6:
+			if (!n--) break;
+			*args++ = regs->bp;
+		case 5:
+			if (!n--) break;
+			*args++ = regs->di;
+		case 4:
+			if (!n--) break;
+			*args++ = regs->si;
+		case 3:
+			if (!n--) break;
+			*args++ = regs->dx;
+		case 2:
+			if (!n--) break;
+			*args++ = regs->cx;
+		case 1:
+			if (!n--) break;
+			*args++ = regs->bx;
+		case 0:
+			if (!n--) break;
+		default:
+			BUG();
+			break;
+		}
+	else
+# endif
+		switch (i + n) {
+		case 6:
+			if (!n--) break;
+			*args++ = regs->r9;
+		case 5:
+			if (!n--) break;
+			*args++ = regs->r8;
+		case 4:
+			if (!n--) break;
+			*args++ = regs->r10;
+		case 3:
+			if (!n--) break;
+			*args++ = regs->dx;
+		case 2:
+			if (!n--) break;
+			*args++ = regs->si;
+		case 1:
+			if (!n--) break;
+			*args++ = regs->di;
+		case 0:
+			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 + n) {
+		case 6:
+			if (!n--) break;
+			regs->bp = *args++;
+		case 5:
+			if (!n--) break;
+			regs->di = *args++;
+		case 4:
+			if (!n--) break;
+			regs->si = *args++;
+		case 3:
+			if (!n--) break;
+			regs->dx = *args++;
+		case 2:
+			if (!n--) break;
+			regs->cx = *args++;
+		case 1:
+			if (!n--) break;
+			regs->bx = *args++;
+		case 0:
+			if (!n--) break;
+		default:
+			BUG();
+		}
+	else
+# endif
+		switch (i + n) {
+		case 6:
+			if (!n--) break;
+			regs->r9 = *args++;
+		case 5:
+			if (!n--) break;
+			regs->r8 = *args++;
+		case 4:
+			if (!n--) break;
+			regs->r10 = *args++;
+		case 3:
+			if (!n--) break;
+			regs->dx = *args++;
+		case 2:
+			if (!n--) break;
+			regs->si = *args++;
+		case 1:
+			if (!n--) break;
+			regs->di = *args++;
+		case 0:
+			if (!n--) break;
+		default:
+			BUG();
+		}
+}
+
+#endif	/* CONFIG_X86_32 */
+
+#endif	/* _ASM_SYSCALL_H */