[21/28] linux: Implement mremap in C

Message ID 20201118195552.2687336-22-adhemerval.zanella@linaro.org
State Superseded
Headers
Series More Linux syscall refactor |

Commit Message

Adhemerval Zanella Nov. 18, 2020, 7:55 p.m. UTC
  This avoid variadic function in syscalls.list and the possible mismatch
between the asm syscall macros the required ABI to handle the variadic
argument.

Checked on x86_64-linux-gnu.
---
 sysdeps/unix/sysv/linux/Makefile      |  2 +-
 sysdeps/unix/sysv/linux/mremap.c      | 41 +++++++++++++++++++++++++++
 sysdeps/unix/sysv/linux/syscalls.list |  1 -
 3 files changed, 42 insertions(+), 2 deletions(-)
 create mode 100644 sysdeps/unix/sysv/linux/mremap.c
  

Patch

diff --git a/sysdeps/unix/sysv/linux/Makefile b/sysdeps/unix/sysv/linux/Makefile
index c3b24f9332..68818862dd 100644
--- a/sysdeps/unix/sysv/linux/Makefile
+++ b/sysdeps/unix/sysv/linux/Makefile
@@ -61,7 +61,7 @@  sysdep_routines += adjtimex clone umount umount2 readahead sysctl \
 		   open_by_handle_at mlock2 pkey_mprotect pkey_set pkey_get \
 		   timerfd_gettime timerfd_settime prctl \
 		   process_vm_readv process_vm_writev clock_adjtime \
-		   time64-support pselect32 fanotify_mark
+		   time64-support pselect32 fanotify_mark mremap
 
 CFLAGS-gethostid.c = -fexceptions
 CFLAGS-tee.c = -fexceptions -fasynchronous-unwind-tables
diff --git a/sysdeps/unix/sysv/linux/mremap.c b/sysdeps/unix/sysv/linux/mremap.c
new file mode 100644
index 0000000000..83b4e95338
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/mremap.c
@@ -0,0 +1,41 @@ 
+/* Remap a virtual memory address.  Linux specific syscall.
+   Copyright (C) 2020 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <sys/mman.h>
+#include <sysdep.h>
+#include <stdarg.h>
+#include <stddef.h>
+
+void *
+__mremap (void *addr, size_t old_len, size_t new_len, int flags, ...)
+{
+  va_list va;
+  void *new_addr = NULL;
+
+  if (flags & MREMAP_FIXED)
+    {
+      va_start (va, flags);
+      new_addr = va_arg (va, void *);
+      va_end (va);
+    }
+
+  return (void *) INLINE_SYSCALL_CALL (mremap, addr, old_len, new_len, flags,
+				       new_addr);
+}
+libc_hidden_def (__mremap)
+weak_alias (__mremap, mremap)
diff --git a/sysdeps/unix/sysv/linux/syscalls.list b/sysdeps/unix/sysv/linux/syscalls.list
index 01ec2bfa95..7a0172a422 100644
--- a/sysdeps/unix/sysv/linux/syscalls.list
+++ b/sysdeps/unix/sysv/linux/syscalls.list
@@ -35,7 +35,6 @@  mincore		-	mincore		i:aUV	mincore
 mlock		-	mlock		i:bU	mlock
 mlockall	-	mlockall	i:i	mlockall
 mount		EXTRA	mount		i:sssUp	__mount	mount
-mremap		EXTRA	mremap		b:aUUip	__mremap	mremap
 munlock		-	munlock		i:aU	munlock
 munlockall	-	munlockall	i:	munlockall
 nfsservctl	EXTRA	nfsservctl	i:ipp	__compat_nfsservctl	nfsservctl@GLIBC_2.0:GLIBC_2.28