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Fix MIPS mmap negative offset handling for consistency (bug 19550) [committed]

The handling of negative offsets in MIPS mmap is inconsistent with
other architectures, as shown by failure of the test
posix/tst-mmap-offset for o32 and n32.  The MIPS mmap syscall uses a
signed argument and does a signed arithmetic shift on it, whereas the
glibc semantics expected by that test are for the offset to be
considered as a large positive offset.  This patch makes MIPS
consistent with other architectures as far as possible by using the
mmap2 syscall on o32 (#including the generic implementation), and
making mmap not an alias for mmap64 for n32, with a custom
implementation for n32 that zero-extends the offset argument to 64-bit
before calling the mmap syscall.

Tested for MIPS64 (o32, n32, n64).  Committed.

2016-02-01  Joseph Myers  <>

	[BZ #19550]
	* sysdeps/unix/sysv/linux/mips/mips32/mmap.c: New file.
	* sysdeps/unix/sysv/linux/mips/mips64/mmap64.c: Move to ....
	* sysdeps/unix/sysv/linux/mips/mips64/n64/mmap64.c: ... here.
	* sysdeps/unix/sysv/linux/mips/mips64/n32/mmap.c: New file.
	* sysdeps/unix/sysv/linux/mips/mips64/n32/syscalls.list (mmap64):
	New syscall entry.
	* sysdeps/unix/sysv/linux/mips/mips64/n64/syscalls.list (mmap):
	New syscall entry.
	* sysdeps/unix/sysv/linux/mips/mips64/syscalls.list (mmap): Remove
	syscall entry.

diff --git a/sysdeps/unix/sysv/linux/mips/mips32/mmap.c b/sysdeps/unix/sysv/linux/mips/mips32/mmap.c
new file mode 100644
index 0000000..f30b1da
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/mips/mips32/mmap.c
@@ -0,0 +1 @@
+#include <sysdeps/unix/sysv/linux/generic/wordsize-32/mmap.c>
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/mmap64.c b/sysdeps/unix/sysv/linux/mips/mips64/mmap64.c
deleted file mode 100644
index 0dbd384..0000000
--- a/sysdeps/unix/sysv/linux/mips/mips64/mmap64.c
+++ /dev/null
@@ -1 +0,0 @@
-/* mmap64 is the same as mmap. */
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n32/mmap.c b/sysdeps/unix/sysv/linux/mips/mips64/n32/mmap.c
new file mode 100644
index 0000000..7afe776
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n32/mmap.c
@@ -0,0 +1,35 @@
+/* mmap for MIPS n32.
+   Copyright (C) 2016 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
+   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
+   <>.  */
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <errno.h>
+#include <stdint.h>
+#include <sysdep.h>
+__mmap (__ptr_t addr, size_t len, int prot, int flags, int fd, off_t offset)
+  /* To handle negative offsets consistently with other architectures,
+     the offset must be zero-extended to 64-bit.  */
+  uint64_t offset_adj = (uint64_t) (uint32_t) offset;
+  return (__ptr_t) INLINE_SYSCALL (mmap, 6, addr, len, prot, flags, fd,
+				   offset_adj);
+weak_alias (__mmap, mmap)
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n32/syscalls.list b/sysdeps/unix/sysv/linux/mips/mips64/n32/syscalls.list
index 584ad1f..f55a94a 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n32/syscalls.list
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n32/syscalls.list
@@ -1,5 +1,7 @@
 # File name	Caller	Syscall name	# args	Strong name	Weak names
+mmap64		-	mmap		b:aniiii __mmap64	mmap64
 readahead	-	readahead	i:iii	__readahead	readahead
 sync_file_range	-	sync_file_range	Ci:iiii	sync_file_range
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n64/mmap64.c b/sysdeps/unix/sysv/linux/mips/mips64/n64/mmap64.c
new file mode 100644
index 0000000..0dbd384
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n64/mmap64.c
@@ -0,0 +1 @@
+/* mmap64 is the same as mmap. */
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n64/syscalls.list b/sysdeps/unix/sysv/linux/mips/mips64/n64/syscalls.list
index b23a2a1..890a744 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n64/syscalls.list
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n64/syscalls.list
@@ -1,5 +1,7 @@
 # File name	Caller	Syscall name	# args	Strong name	Weak names
+mmap		-	mmap		b:aniiii __mmap		mmap __mmap64 mmap64
 sync_file_range	-	sync_file_range	Ci:iiii	sync_file_range
 prlimit		EXTRA	prlimit64	i:iipp	prlimit		prlimit64
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/syscalls.list b/sysdeps/unix/sysv/linux/mips/mips64/syscalls.list
index 6c80e27..66cc687 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/syscalls.list
+++ b/sysdeps/unix/sysv/linux/mips/mips64/syscalls.list
@@ -2,8 +2,6 @@
 lseek		-	lseek		i:iii	__libc_lseek	__lseek lseek __llseek llseek __libc_lseek64 __lseek64 lseek64
-mmap		-	mmap		b:aniiii __mmap		mmap __mmap64 mmap64
 ftruncate	-	ftruncate	i:ii	__ftruncate	ftruncate ftruncate64 __ftruncate64
 truncate	-	truncate	i:si	truncate	truncate64

Joseph S. Myers

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