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[PATCH] Change sync_file_range to be non-cancellable

This patch changes the linux specific sync_file_range syscalls to be
non-cancellable.  The rationale is:

1. This is a Linux specific syscall that is not mentioned in POSIX
   cancellable entrypoints [1] and the standard states and implementation
   shall not introduce cancellation points into any other functions
   specified.

2. For mips it requires 7 arguments, which will make the new
   cancellation code require very specific handling for the platform.

3. It aligns with other implementations (musl) which does not set
   sync_file_range as cancellable.

Also since GLIBC requires a minimum 2.6.32 kernel, the patch also
cleanups the mips code to assume __NR_sync_file_range and the
powerpc one to either assume __NR_sync_file_range2 or __NR_sync_file_range.

Checked on x86_64, i386, powerpc64le and build for mips (ABIO32, ABIN32,
and ABI64).

[1] http://pubs.opengroup.org/onlinepubs/9699919799/

	* sysdeps/unix/sysv/linux/powerpc/powerpc64/sync_file_range.c
	(__NR_sync_file_range2): Assume it is always defined.
	(sync_file_range): Make syscall non-cancellable.
	* sysdeps/unix/sysv/linux/mips/mips32/sync_file_range.c
	(__NR_sync_file_range): Assume it is always defined.
	(sync_file_range): Make syscall non-cancellable.
	* sysdeps/unix/sysv/linux/mips/mips64/n32/syscalls.list
	(sync_file_range): Likewise.
	* sysdeps/unix/sysv/linux/mips/mips64/n64/syscalls.list
	(sync_file_range): Likewise.
	* sysdeps/unix/sysv/linux/sync_file_range.c (sync_file_range):
	Likewise.
	* sysdeps/unix/sysv/linux/wordsize-64/syscalls.list (sync_file_range):
	Likewise.
---
 ChangeLog                                                 | 15 +++++++++++++++
 sysdeps/unix/sysv/linux/mips/mips32/sync_file_range.c     | 13 +------------
 sysdeps/unix/sysv/linux/mips/mips64/n32/syscalls.list     |  2 +-
 sysdeps/unix/sysv/linux/mips/mips64/n64/syscalls.list     |  2 +-
 .../unix/sysv/linux/powerpc/powerpc64/sync_file_range.c   | 13 +------------
 sysdeps/unix/sysv/linux/sync_file_range.c                 |  4 ++--
 sysdeps/unix/sysv/linux/wordsize-64/syscalls.list         |  2 +-
 7 files changed, 22 insertions(+), 29 deletions(-)

diff --git a/sysdeps/unix/sysv/linux/mips/mips32/sync_file_range.c b/sysdeps/unix/sysv/linux/mips/mips32/sync_file_range.c
index b79e44d..ce82f30 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/sync_file_range.c
+++ b/sysdeps/unix/sysv/linux/mips/mips32/sync_file_range.c
@@ -23,22 +23,11 @@
 #include <sysdep-cancel.h>
 #include <sys/syscall.h>
 
-
-#ifdef __NR_sync_file_range
 int
 sync_file_range (int fd, __off64_t from, __off64_t to, unsigned int flags)
 {
-  return SYSCALL_CANCEL (sync_file_range, fd, 0,
+  return INLINE_SYSCALL (sync_file_range, 7, fd, 0,
 			 __LONG_LONG_PAIR ((long) (from >> 32), (long) from),
 			 __LONG_LONG_PAIR ((long) (to >> 32), (long) to),
 			 flags);
 }
-#else
-int
-sync_file_range (int fd, __off64_t from, __off64_t to, unsigned int flags)
-{
-  __set_errno (ENOSYS);
-  return -1;
-}
-stub_warning (sync_file_range)
-#endif
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n32/syscalls.list b/sysdeps/unix/sysv/linux/mips/mips64/n32/syscalls.list
index 7ad5523..0148e42 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n32/syscalls.list
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n32/syscalls.list
@@ -1,7 +1,7 @@
 # File name	Caller	Syscall name	# args	Strong name	Weak names
 
 readahead	-	readahead	i:iii	__readahead	readahead
-sync_file_range	-	sync_file_range	Ci:iiii	sync_file_range
+sync_file_range	-	sync_file_range	i:iiii	sync_file_range
 
 prlimit64	EXTRA	prlimit64	i:iipp	prlimit64
 
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n64/syscalls.list b/sysdeps/unix/sysv/linux/mips/mips64/n64/syscalls.list
index b23a2a1..e4fac08 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n64/syscalls.list
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n64/syscalls.list
@@ -1,6 +1,6 @@
 # File name	Caller	Syscall name	# args	Strong name	Weak names
 
-sync_file_range	-	sync_file_range	Ci:iiii	sync_file_range
+sync_file_range	-	sync_file_range	i:iiii	sync_file_range
 
 prlimit		EXTRA	prlimit64	i:iipp	prlimit		prlimit64
 
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/sync_file_range.c b/sysdeps/unix/sysv/linux/powerpc/powerpc64/sync_file_range.c
index 9f46458..d3d54ef 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/sync_file_range.c
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/sync_file_range.c
@@ -23,19 +23,8 @@
 #include <sysdep-cancel.h>
 #include <sys/syscall.h>
 
-
-#if defined __NR_sync_file_range2
-int
-sync_file_range (int fd, __off64_t from, __off64_t to, unsigned int flags)
-{
-  return SYSCALL_CANCEL (sync_file_range2, fd, flags, from, to);
-}
-#else
 int
 sync_file_range (int fd, __off64_t from, __off64_t to, unsigned int flags)
 {
-  __set_errno (ENOSYS);
-  return -1;
+  return INLINE_SYSCALL (sync_file_range2, 4, fd, flags, from, to);
 }
-stub_warning (sync_file_range)
-#endif
diff --git a/sysdeps/unix/sysv/linux/sync_file_range.c b/sysdeps/unix/sysv/linux/sync_file_range.c
index 2ea6dcf..69b128a 100644
--- a/sysdeps/unix/sysv/linux/sync_file_range.c
+++ b/sysdeps/unix/sysv/linux/sync_file_range.c
@@ -28,7 +28,7 @@
 int
 sync_file_range (int fd, __off64_t from, __off64_t to, unsigned int flags)
 {
-  return SYSCALL_CANCEL (sync_file_range, fd,
+  return INLINE_SYSCALL (sync_file_range, 6, fd,
 			 __LONG_LONG_PAIR ((long) (from >> 32), (long) from),
 			 __LONG_LONG_PAIR ((long) (to >> 32), (long) to),
 			 flags);
@@ -37,7 +37,7 @@ sync_file_range (int fd, __off64_t from, __off64_t to, unsigned int flags)
 int
 sync_file_range (int fd, __off64_t from, __off64_t to, unsigned int flags)
 {
-  return SYSCALL_CANCEL (sync_file_range2, fd, flags,
+  return INLINE_SYSCALL (sync_file_range2, 6, fd, flags,
 			 __LONG_LONG_PAIR ((long) (from >> 32), (long) from),
 			 __LONG_LONG_PAIR ((long) (to >> 32), (long) to));
 }
diff --git a/sysdeps/unix/sysv/linux/wordsize-64/syscalls.list b/sysdeps/unix/sysv/linux/wordsize-64/syscalls.list
index 51ee8d8..55e62f3 100644
--- a/sysdeps/unix/sysv/linux/wordsize-64/syscalls.list
+++ b/sysdeps/unix/sysv/linux/wordsize-64/syscalls.list
@@ -14,7 +14,7 @@ getrlimit	-	getrlimit	i:ip	__getrlimit	getrlimit getrlimit64 __getrlimit64
 setrlimit	-	setrlimit	i:ip	__setrlimit	setrlimit setrlimit64
 readahead	-	readahead	i:iii	__readahead	readahead
 sendfile	-	sendfile	i:iipi	sendfile	sendfile64
-sync_file_range	-	sync_file_range	Ci:iiii	sync_file_range
+sync_file_range	-	sync_file_range	i:iiii	sync_file_range
 creat		-	creat		Ci:si	creat		creat64
 open		-	open		Ci:siv	__libc_open	__open open __open64 open64
 prlimit		EXTRA	prlimit64	i:iipp	prlimit		prlimit64
-- 
1.9.1
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