move x86 copy_user.[ch] to ipc/ and make it arch-indipendent

Message-ID: <20240309140244.347835-3-luca@orpolo.org>

1 files changed, 100 insertions, 0 deletions

diff --git a/ipc/copy_user.h b/ipc/copy_user.h
new file mode 100644
index 00000000..a57b3ee5
--- /dev/null
+++ b/ipc/copy_user.h
@@ -0,0 +1,100 @@
+/*
+ *  Copyright (C) 2023 Free Software Foundation
+ *
+ * This program is free software ; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation ; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY ; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with the program ; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#ifndef COPY_USER_H
+#define COPY_USER_H
+
+#include <stdint.h>
+#include <sys/types.h>
+
+#include <machine/locore.h>
+#include <mach/message.h>
+
+/*
+ * The copyin_32to64() and copyout_64to32() routines are meant for data types
+ * that have different size in kernel and user space. They should be independent
+ * of endianness and hopefully can be reused on all archs.
+ * These types are e.g.:
+ * - port names vs port pointers, on a 64-bit kernel
+ * - memory addresses, on a 64-bit kernel and 32-bit user
+ */
+
+static inline int copyin_32to64(const uint32_t *uaddr, uint64_t *kaddr)
+{
+  uint32_t rkaddr;
+  int ret;
+  ret = copyin(uaddr, &rkaddr, sizeof(uint32_t));
+  if (ret)
+    return ret;
+  *kaddr = rkaddr;
+  return 0;
+}
+
+static inline int copyout_64to32(const uint64_t *kaddr, uint32_t *uaddr)
+{
+  uint32_t rkaddr=*kaddr;
+  return copyout(&rkaddr, uaddr, sizeof(uint32_t));
+}
+
+static inline int copyin_address(const rpc_vm_offset_t *uaddr, vm_offset_t *kaddr)
+{
+#ifdef USER32
+  return copyin_32to64(uaddr, kaddr);
+#else /* USER32 */
+  return copyin(uaddr, kaddr, sizeof(*uaddr));
+#endif /* USER32 */
+}
+
+static inline int copyout_address(const vm_offset_t *kaddr, rpc_vm_offset_t *uaddr)
+{
+#ifdef USER32
+  return copyout_64to32(kaddr, uaddr);
+#else /* USER32 */
+  return copyout(kaddr, uaddr, sizeof(*kaddr));
+#endif /* USER32 */
+}
+
+static inline int copyin_port(const mach_port_name_t *uaddr, mach_port_t *kaddr)
+{
+#ifdef __LP64__
+  return copyin_32to64(uaddr, kaddr);
+#else /* __LP64__ */
+  return copyin(uaddr, kaddr, sizeof(*uaddr));
+#endif /* __LP64__ */
+}
+
+static inline int copyout_port(const mach_port_t *kaddr, mach_port_name_t *uaddr)
+{
+#ifdef __LP64__
+  return copyout_64to32(kaddr, uaddr);
+#else /* __LP64__ */
+  return copyout(kaddr, uaddr, sizeof(*kaddr));
+#endif /* __LP64__ */
+}
+
+#if defined(__LP64__) && defined(USER32)
+/* For 32 bit userland, kernel and user land messages are not the same size. */
+size_t msg_usize(const mach_msg_header_t *kmsg);
+#else
+static inline size_t msg_usize(const mach_msg_header_t *kmsg)
+{
+  return kmsg->msgh_size;
+}
+#endif /* __LP64__ && USER32 */
+
+#endif /* COPY_USER_H */