[glibc/google/grte/v5-2.27/master] Update RWF_SUPPORTED for Linux kernel 4.16 [BZ #22947]

[glibc/google/grte/v5-2.27/master] Update RWF_SUPPORTED for Linux kernel 4.16 [BZ #22947]

[Fangrui Song]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=c01dc8b1ff12ff99ca9754d339845bf21ee7f8bb

commit c01dc8b1ff12ff99ca9754d339845bf21ee7f8bb
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Tue Apr 3 12:19:20 2018 -0700

    Update RWF_SUPPORTED for Linux kernel 4.16 [BZ #22947]
    
    Add RWF_APPEND to RWF_SUPPORTED to support Linux kernel 4.16.
    
            [BZ #22947]
            * bits/uio-ext.h (RWF_APPEND): New.
            * sysdeps/unix/sysv/linux/bits/uio-ext.h (RWF_APPEND): Likewise.
            * manual/llio.texi: Document RWF_APPEND.
            * misc/tst-preadvwritev2-common.c (RWF_APPEND): New.
            (RWF_SUPPORTED): Add RWF_APPEND.
    
    (cherry picked from commit f2652643d7234c08205b75f527191c2e2b35251f)

Diff:
---
 ChangeLog                              | 9 +++++++++
 bits/uio-ext.h                         | 1 +
 manual/llio.texi                       | 3 +++
 misc/tst-preadvwritev2-common.c        | 6 +++++-
 sysdeps/unix/sysv/linux/bits/uio-ext.h | 1 +
 5 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/ChangeLog b/ChangeLog
index 670c6d94b8..bbf9af1fb8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2018-04-03  H.J. Lu  <hongjiu.lu@intel.com>
+
+	[BZ #22947]
+	* bits/uio-ext.h (RWF_APPEND): New.
+	* sysdeps/unix/sysv/linux/bits/uio-ext.h (RWF_APPEND): Likewise.
+	* manual/llio.texi: Document RWF_APPEND.
+	* misc/tst-preadvwritev2-common.c (RWF_APPEND): New.
+	(RWF_SUPPORTED): Add RWF_APPEND.
+
 2018-03-27  Jesse Hathaway  <jesse@mbuki-mvuki.org>
 
 	* sysdeps/unix/sysv/linux/getlogin_r.c (__getlogin_r_loginuid): Return
diff --git a/bits/uio-ext.h b/bits/uio-ext.h
index 8c15a05d9a..d5aa06fd08 100644
--- a/bits/uio-ext.h
+++ b/bits/uio-ext.h
@@ -28,5 +28,6 @@
 #define RWF_DSYNC	0x00000002 /* per-IO O_DSYNC.  */
 #define RWF_SYNC	0x00000004 /* per-IO O_SYNC.  */
 #define RWF_NOWAIT	0x00000008 /* per-IO nonblocking mode.  */
+#define RWF_APPEND	0x00000010 /* per-IO O_APPEND.  */
 
 #endif /* sys/uio_ext.h */
diff --git a/manual/llio.texi b/manual/llio.texi
index 642e56e710..7d877992d9 100644
--- a/manual/llio.texi
+++ b/manual/llio.texi
@@ -1271,6 +1271,9 @@ Per-IO synchronization as if the file was opened with @code{O_SYNC} flag.
 @item RWF_NOWAIT
 Use nonblocking mode for this operation; that is, this call to @code{preadv2}
 will fail and set @code{errno} to @code{EAGAIN} if the operation would block.
+
+@item RWF_APPEND
+Per-IO synchronization as if the file was opened with @code{O_APPEND} flag.
 @end vtable
 
 When the source file is compiled with @code{_FILE_OFFSET_BITS == 64} the
diff --git a/misc/tst-preadvwritev2-common.c b/misc/tst-preadvwritev2-common.c
index 89fd0a3ff5..f889a21544 100644
--- a/misc/tst-preadvwritev2-common.c
+++ b/misc/tst-preadvwritev2-common.c
@@ -34,7 +34,11 @@ do_test_with_invalid_flags (void)
 #ifndef RWF_NOWAIT
 # define RWF_NOWAIT 0
 #endif
-#define RWF_SUPPORTED	(RWF_HIPRI | RWF_DSYNC | RWF_SYNC | RWF_NOWAIT)
+#ifndef RWF_APPEND
+# define RWF_APPEND 0
+#endif
+#define RWF_SUPPORTED	(RWF_HIPRI | RWF_DSYNC | RWF_SYNC | RWF_NOWAIT \
+			 | RWF_APPEND)
   /* Set the next bit from the mask of all supported flags.  */
   int invalid_flag = RWF_SUPPORTED != 0 ? __builtin_clz (RWF_SUPPORTED) : 2;
   invalid_flag = 0x1 << ((sizeof (int) * CHAR_BIT) - invalid_flag);
diff --git a/sysdeps/unix/sysv/linux/bits/uio-ext.h b/sysdeps/unix/sysv/linux/bits/uio-ext.h
index 53663ed1a2..8698bc1200 100644
--- a/sysdeps/unix/sysv/linux/bits/uio-ext.h
+++ b/sysdeps/unix/sysv/linux/bits/uio-ext.h
@@ -46,6 +46,7 @@ extern ssize_t process_vm_writev (pid_t __pid, const struct iovec *__lvec,
 #define RWF_DSYNC	0x00000002 /* per-IO O_DSYNC.  */
 #define RWF_SYNC	0x00000004 /* per-IO O_SYNC.  */
 #define RWF_NOWAIT	0x00000008 /* per-IO nonblocking mode.  */
+#define RWF_APPEND	0x00000010 /* per-IO O_APPEND.  */
 
 __END_DECLS