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-rw-r--r--arch/x86/include/asm/syscall.h137
1 files changed, 137 insertions, 0 deletions
diff --git a/arch/x86/include/asm/syscall.h b/arch/x86/include/asm/syscall.h
new file mode 100644
index 0000000000..4fb36fba4b
--- /dev/null
+++ b/arch/x86/include/asm/syscall.h
@@ -0,0 +1,137 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Access to user system call parameters and results
+ *
+ * Copyright (C) 2008-2009 Red Hat, Inc. All rights reserved.
+ *
+ * See asm-generic/syscall.h for descriptions of what we must do here.
+ */
+
+#ifndef _ASM_X86_SYSCALL_H
+#define _ASM_X86_SYSCALL_H
+
+#include <uapi/linux/audit.h>
+#include <linux/sched.h>
+#include <linux/err.h>
+#include <asm/thread_info.h> /* for TS_COMPAT */
+#include <asm/unistd.h>
+
+typedef long (*sys_call_ptr_t)(const struct pt_regs *);
+extern const sys_call_ptr_t sys_call_table[];
+
+#if defined(CONFIG_X86_32)
+#define ia32_sys_call_table sys_call_table
+#else
+/*
+ * These may not exist, but still put the prototypes in so we
+ * can use IS_ENABLED().
+ */
+extern const sys_call_ptr_t ia32_sys_call_table[];
+extern const sys_call_ptr_t x32_sys_call_table[];
+#endif
+
+/*
+ * 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.status & (TS_COMPAT|TS_I386_REGS_POKED))
+ /*
+ * 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 long *args)
+{
+ memcpy(args, &regs->bx, 6 * sizeof(args[0]));
+}
+
+static inline int syscall_get_arch(struct task_struct *task)
+{
+ return AUDIT_ARCH_I386;
+}
+
+#else /* CONFIG_X86_64 */
+
+static inline void syscall_get_arguments(struct task_struct *task,
+ struct pt_regs *regs,
+ unsigned long *args)
+{
+# ifdef CONFIG_IA32_EMULATION
+ if (task->thread_info.status & TS_COMPAT) {
+ *args++ = regs->bx;
+ *args++ = regs->cx;
+ *args++ = regs->dx;
+ *args++ = regs->si;
+ *args++ = regs->di;
+ *args = regs->bp;
+ } else
+# endif
+ {
+ *args++ = regs->di;
+ *args++ = regs->si;
+ *args++ = regs->dx;
+ *args++ = regs->r10;
+ *args++ = regs->r8;
+ *args = regs->r9;
+ }
+}
+
+static inline int syscall_get_arch(struct task_struct *task)
+{
+ /* x32 tasks should be considered AUDIT_ARCH_X86_64. */
+ return (IS_ENABLED(CONFIG_IA32_EMULATION) &&
+ task->thread_info.status & TS_COMPAT)
+ ? AUDIT_ARCH_I386 : AUDIT_ARCH_X86_64;
+}
+
+void do_syscall_64(struct pt_regs *regs, int nr);
+
+#endif /* CONFIG_X86_32 */
+
+void do_int80_syscall_32(struct pt_regs *regs);
+long do_fast_syscall_32(struct pt_regs *regs);
+long do_SYSENTER_32(struct pt_regs *regs);
+
+#endif /* _ASM_X86_SYSCALL_H */