* misc/Makefile (routines): Add preadv, preadv64, pwritev, pwritev64.

	* misc/Versions: Export preadv, preadv64, pwritev, pwritev64 for
	GLIBC_2.10.
	* misc/sys/uio.h: Declare preadv, preadv64, pwritev, pwritev64.
	* sysdeps/unix/sysv/linux/kernel-features.h: Add entries for preadv
	and pwritev.
	* misc/preadv.c: New file.
	* misc/preadv64.c: New file.
	* misc/pwritev.c: New file.
	* misc/pwritev64.c: New file.
	* sysdeps/posx/preadv.c: New file.
	* sysdeps/posx/preadv64.c: New file.
	* sysdeps/posx/pwritev.c: New file.
	* sysdeps/posx/pwritev64.c: New file.
	* sysdeps/unix/sysv/linux/preadv.c: New file.
	* sysdeps/unix/sysv/linux/preadv64.c: New file.
	* sysdeps/unix/sysv/linux/pwritev.c: New file.
	* sysdeps/unix/sysv/linux/pwritev64.c: New file.
	* sysdeps/unix/sysv/linux/wordsize-64/preadv64.c: New file.
	* sysdeps/unix/sysv/linux/wordsize-64/pwritev64.c: New file.

20 files changed, 708 insertions, 9 deletions

diff --git a/ChangeLog b/ChangeLog
index 8b4217a..3463b94 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,26 @@
 2009-04-03  Ulrich Drepper  <drepper@redhat.com>
 
+	* misc/Makefile (routines): Add preadv, preadv64, pwritev, pwritev64.
+	* misc/Versions: Export preadv, preadv64, pwritev, pwritev64 for
+	GLIBC_2.10.
+	* misc/sys/uio.h: Declare preadv, preadv64, pwritev, pwritev64.
+	* sysdeps/unix/sysv/linux/kernel-features.h: Add entries for preadv
+	and pwritev.
+	* misc/preadv.c: New file.
+	* misc/preadv64.c: New file.
+	* misc/pwritev.c: New file.
+	* misc/pwritev64.c: New file.
+	* sysdeps/posx/preadv.c: New file.
+	* sysdeps/posx/preadv64.c: New file.
+	* sysdeps/posx/pwritev.c: New file.
+	* sysdeps/posx/pwritev64.c: New file.
+	* sysdeps/unix/sysv/linux/preadv.c: New file.
+	* sysdeps/unix/sysv/linux/preadv64.c: New file.
+	* sysdeps/unix/sysv/linux/pwritev.c: New file.
+	* sysdeps/unix/sysv/linux/pwritev64.c: New file.
+	* sysdeps/unix/sysv/linux/wordsize-64/preadv64.c: New file.
+	* sysdeps/unix/sysv/linux/wordsize-64/pwritev64.c: New file.
+
 	* sysdeps/unix/sysv/linux/readv.c (__libc_readv): Fix calling of
 	compatibility code.
 	* sysdeps/unix/sysv/linux/writev.c (__libc_writev): Likewise.
diff --git a/NEWS b/NEWS
index 686d5df..a91af3b 100644
--- a/NEWS
+++ b/NEWS
@@ -1,4 +1,4 @@
-GNU C Library NEWS -- history of user-visible changes.  2009-3-14
+GNU C Library NEWS -- history of user-visible changes.  2009-4-3
 Copyright (C) 1992-2008, 2009 Free Software Foundation, Inc.
 See the end for copying conditions.
 
@@ -7,7 +7,11 @@ using `glibc' in the "product" field.
 
 Version 2.10
 
+* New interfaces: preadv, preadv64, pwritev, pwritev64
+  Implemented by Ulrich Drepper.
+
 * New Linux interfaces: accept4, fallocate, fallocate64.
+  Implemented by Ulrich Drepper.
 
 * Correct declarations of string function when used in C++ code.  This
   could lead to compile error for invalid C++ code.
@@ -24,6 +28,13 @@ Version 2.10
 * Support for selecting between multiple function definitions at runtime
   using STT_GNU_IFUNC symbols.  Implemented by Ulrich Drepper.
 
+* The libcrypt library can now use the hash function implementations in
+  NSS.  Implemented by Ulrich Drepper.
+
+* The malloc implementation can be compiled to be less memory efficient
+  but higher performing in multi-threaded programs.
+  Implemented by Ulrich Drepper.
+
 * New locale: nan_TW@latin
 
 
diff --git a/misc/Makefile b/misc/Makefile
index a256068..1357634 100644
--- a/misc/Makefile
+++ b/misc/Makefile
@@ -34,7 +34,7 @@ headers	:= sys/uio.h bits/uio.h sys/ioctl.h bits/ioctls.h bits/ioctl-types.h \
 	   bits/syslog.h bits/syslog-ldbl.h bits/syslog-path.h bits/error.h
 
 routines := brk sbrk sstk ioctl \
-	    readv writev \
+	    readv writev preadv preadv64 pwritev pwritev64 \
 	    setreuid setregid \
 	    seteuid setegid \
 	    getpagesize \
diff --git a/misc/Versions b/misc/Versions
index b182f12..c930eea 100644
--- a/misc/Versions
+++ b/misc/Versions
@@ -137,4 +137,7 @@ libc {
   GLIBC_2.7 {
     mkostemp; mkostemp64;
   }
+  GLIBC_2.10 {
+    preadv; preadv64; pwritev; pwritev64;
+  }
 }
diff --git a/misc/preadv.c b/misc/preadv.c
new file mode 100644
index 0000000..3e2cc68
--- /dev/null
+++ b/misc/preadv.c
@@ -0,0 +1,41 @@
+/* Copyright (C) 2009 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <errno.h>
+#include <unistd.h>
+#include <sys/uio.h>
+
+/* Read data from file descriptor FD at the given position OFFSET
+   without change the file pointer, and put the result in the buffers
+   described by VECTOR, which is a vector of COUNT 'struct iovec's.
+   The buffers are filled in the order specified.  Operates just like
+   'read' (see <unistd.h>) except that data are put in VECTOR instead
+   of a contiguous buffer.  */
+ssize_t
+preadv (fd, vector, count, offset)
+     int fd;
+     const struct iovec *vector;
+     int count;
+     off_t offset;
+{
+  __set_errno (ENOSYS);
+  return -1;
+}
+
+stub_warning (preadv)
+#include <stub-tag.h>
diff --git a/misc/preadv64.c b/misc/preadv64.c
new file mode 100644
index 0000000..ea675bb
--- /dev/null
+++ b/misc/preadv64.c
@@ -0,0 +1,41 @@
+/* Copyright (C) 2009 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <errno.h>
+#include <unistd.h>
+#include <sys/uio.h>
+
+/* Read data from file descriptor FD at the given position OFFSET
+   without change the file pointer, and put the result in the buffers
+   described by VECTOR, which is a vector of COUNT 'struct iovec's.
+   The buffers are filled in the order specified.  Operates just like
+   'read' (see <unistd.h>) except that data are put in VECTOR instead
+   of a contiguous buffer.  */
+ssize_t
+preadv64 (fd, vector, count, offset)
+     int fd;
+     const struct iovec *vector;
+     int count;
+     off64_t offset;
+{
+  __set_errno (ENOSYS);
+  return -1;
+}
+
+stub_warning (preadv64)
+#include <stub-tag.h>
diff --git a/misc/pwritev.c b/misc/pwritev.c
new file mode 100644
index 0000000..d45ed23
--- /dev/null
+++ b/misc/pwritev.c
@@ -0,0 +1,41 @@
+/* Copyright (C) 2009 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <errno.h>
+#include <unistd.h>
+#include <sys/uio.h>
+
+/* Write data pointed by the buffers described by VECTOR, which is a
+   vector of COUNT 'struct iovec's, to file descriptor FD at the given
+   position OFFSET without change the file pointer.  The data is
+   written in the order specified.  Operates just like 'write' (see
+   <unistd.h>) except that the data are taken from VECTOR instead of a
+   contiguous buffer.  */
+ssize_t
+pwritev (fd, vector, count, offset)
+     int fd;
+     const struct iovec *vector;
+     int count;
+     off_t offset;
+{
+  __set_errno (ENOSYS);
+  return -1;
+}
+
+stub_warning (pwritev)
+#include <stub-tag.h>
diff --git a/misc/pwritev64.c b/misc/pwritev64.c
new file mode 100644
index 0000000..fe95857
--- /dev/null
+++ b/misc/pwritev64.c
@@ -0,0 +1,41 @@
+/* Copyright (C) 2009 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <errno.h>
+#include <unistd.h>
+#include <sys/uio.h>
+
+/* Write data pointed by the buffers described by VECTOR, which is a
+   vector of COUNT 'struct iovec's, to file descriptor FD at the given
+   position OFFSET without change the file pointer.  The data is
+   written in the order specified.  Operates just like 'write' (see
+   <unistd.h>) except that the data are taken from VECTOR instead of a
+   contiguous buffer.  */
+ssize_t
+pwritev64 (fd, vector, count, offset)
+     int fd;
+     const struct iovec *vector;
+     int count;
+     off64_t offset;
+{
+  __set_errno (ENOSYS);
+  return -1;
+}
+
+stub_warning (pwritev64)
+#include <stub-tag.h>
diff --git a/misc/sys/uio.h b/misc/sys/uio.h
index 1b203f7..a3c7829 100644
--- a/misc/sys/uio.h
+++ b/misc/sys/uio.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 1991, 92, 96, 97, 98, 99, 2003 Free Software Foundation, Inc.
+/* Copyright (C) 1991,1992,1996-1999,2003,2009 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
@@ -30,24 +30,93 @@ __BEGIN_DECLS
 
 
 /* Read data from file descriptor FD, and put the result in the
-   buffers described by IOVEC, which is a vector of COUNT `struct iovec's.
+   buffers described by IOVEC, which is a vector of COUNT 'struct iovec's.
    The buffers are filled in the order specified.
-   Operates just like `read' (see <unistd.h>) except that data are
+   Operates just like 'read' (see <unistd.h>) except that data are
    put in IOVEC instead of a contiguous buffer.
 
    This function is a cancellation point and therefore not marked with
    __THROW.  */
-extern ssize_t readv (int __fd, __const struct iovec *__iovec, int __count);
+extern ssize_t readv (int __fd, __const struct iovec *__iovec, int __count)
+  __wur;
 
 /* Write data pointed by the buffers described by IOVEC, which
-   is a vector of COUNT `struct iovec's, to file descriptor FD.
+   is a vector of COUNT 'struct iovec's, to file descriptor FD.
    The data is written in the order specified.
-   Operates just like `write' (see <unistd.h>) except that the data
+   Operates just like 'write' (see <unistd.h>) except that the data
    are taken from IOVEC instead of a contiguous buffer.
 
    This function is a cancellation point and therefore not marked with
    __THROW.  */
-extern ssize_t writev (int __fd, __const struct iovec *__iovec, int __count);
+extern ssize_t writev (int __fd, __const struct iovec *__iovec, int __count)
+  __wur;
+
+
+#ifdef __USE_BSD
+# ifndef __USE_FILE_OFFSET64
+/* Read data from file descriptor FD at the given position OFFSET
+   without change the file pointer, and put the result in the buffers
+   described by IOVEC, which is a vector of COUNT 'struct iovec's.
+   The buffers are filled in the order specified.  Operates just like
+   'read' (see <unistd.h>) except that data are put in IOVEC instead
+   of a contiguous buffer.
+
+   This function is a cancellation point and therefore not marked with
+   __THROW.  */
+extern ssize_t preadv (int __fd, __const struct iovec *__iovec, int __count,
+		       __off_t __offset) __wur;
+
+/* Write data pointed by the buffers described by IOVEC, which is a
+   vector of COUNT 'struct iovec's, to file descriptor FD at the given
+   position OFFSET without change the file pointer.  The data is
+   written in the order specified.  Operates just like 'write' (see
+   <unistd.h>) except that the data are taken from IOVEC instead of a
+   contiguous buffer.
+
+   This function is a cancellation point and therefore not marked with
+   __THROW.  */
+extern ssize_t pwritev (int __fd, __const struct iovec *__iovec, int __count,
+			__off_t __offset) __wur;
+# else
+#  ifdef __REDIRECT
+extern ssize_t __REDIRECT (preadv, (int __fd, __const struct iovec *__iovec,
+				    int __count, __off_t __offset),
+			   preadv64) __wur;
+extern ssize_t __REDIRECT (pwritev, (int __fd, __const struct iovec *__iovec,
+				     int __count, __off_t __offset),
+			   pwritev64) __wur;
+#  else
+#   define preadv preadv64
+#   define pwritev pwritev64
+#  endif
+# endif
+
+# ifdef __USE_LARGEFILE64
+/* Read data from file descriptor FD at the given position OFFSET
+   without change the file pointer, and put the result in the buffers
+   described by IOVEC, which is a vector of COUNT 'struct iovec's.
+   The buffers are filled in the order specified.  Operates just like
+   'read' (see <unistd.h>) except that data are put in IOVEC instead
+   of a contiguous buffer.
+
+   This function is a cancellation point and therefore not marked with
+   __THROW.  */
+extern ssize_t preadv64 (int __fd, __const struct iovec *__iovec, int __count,
+			 __off64_t __offset) __wur;
+
+/* Write data pointed by the buffers described by IOVEC, which is a
+   vector of COUNT 'struct iovec's, to file descriptor FD at the given
+   position OFFSET without change the file pointer.  The data is
+   written in the order specified.  Operates just like 'write' (see
+   <unistd.h>) except that the data are taken from IOVEC instead of a
+   contiguous buffer.
+
+   This function is a cancellation point and therefore not marked with
+   __THROW.  */
+extern ssize_t pwritev64 (int __fd, __const struct iovec *__iovec, int __count,
+			  __off64_t __offset) __wur;
+# endif
+#endif	/* Use BSD */
 
 __END_DECLS
 
diff --git a/sysdeps/posix/preadv.c b/sysdeps/posix/preadv.c
new file mode 100644
index 0000000..e697604
--- /dev/null
+++ b/sysdeps/posix/preadv.c
@@ -0,0 +1,108 @@
+/* Copyright (C) 2009 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <errno.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <limits.h>
+#include <stdbool.h>
+#include <sys/param.h>
+#if __WORDSIZE == 64 && !defined PREADV
+/* Hide the preadv64 declaration.  */
+# define preadv64 __redirect_preadv64
+#endif
+#include <sys/uio.h>
+#include <bits/wordsize.h>
+
+#ifndef PREADV
+# define PREADV preadv
+# define PREAD __pread
+# define OFF_T off_t
+#endif
+
+
+static void
+ifree (char **ptrp)
+{
+  free (*ptrp);
+}
+
+
+/* Read data from file descriptor FD at the given position OFFSET
+   without change the file pointer, and put the result in the buffers
+   described by VECTOR, which is a vector of COUNT 'struct iovec's.
+   The buffers are filled in the order specified.  Operates just like
+   'read' (see <unistd.h>) except that data are put in VECTOR instead
+   of a contiguous buffer.  */
+ssize_t
+PREADV (int fd, const struct iovec *vector, int count, OFF_T offset)
+{
+  /* Find the total number of bytes to be read.  */
+  size_t bytes = 0;
+  for (int i = 0; i < count; ++i)
+    {
+      /* Check for ssize_t overflow.  */
+      if (SSIZE_MAX - bytes < vector[i].iov_len)
+	{
+	  __set_errno (EINVAL);
+	  return -1;
+	}
+      bytes += vector[i].iov_len;
+    }
+
+  /* Allocate a temporary buffer to hold the data.  We should normally
+     use alloca since it's faster and does not require synchronization
+     with other threads.  But we cannot if the amount of memory
+     required is too large.  */
+  char *buffer;
+  char *malloced_buffer __attribute__ ((__cleanup__ (ifree))) = NULL;
+  if (__libc_use_alloca (bytes))
+    buffer = (char *) __alloca (bytes);
+  else
+    {
+      malloced_buffer = buffer = (char *) malloc (bytes);
+      if (buffer == NULL)
+	return -1;
+    }
+
+  /* Read the data.  */
+  ssize_t bytes_read = PREAD (fd, buffer, bytes, offset);
+  if (bytes_read <= 0)
+    return -1;
+
+  /* Copy the data from BUFFER into the memory specified by VECTOR.  */
+  bytes = bytes_read;
+  for (int i = 0; i < count; ++i)
+    {
+      size_t copy = MIN (vector[i].iov_len, bytes);
+
+      (void) memcpy ((void *) vector[i].iov_base, (void *) buffer, copy);
+
+      buffer += copy;
+      bytes -= copy;
+      if (bytes == 0)
+	break;
+    }
+
+  return bytes_read;
+}
+#if __WORDSIZE == 64 && defined preadv64
+# undef preadv64
+strong_alias (preadv, preadv64)
+#endif
diff --git a/sysdeps/posix/preadv64.c b/sysdeps/posix/preadv64.c
new file mode 100644
index 0000000..1986223
--- /dev/null
+++ b/sysdeps/posix/preadv64.c
@@ -0,0 +1,9 @@
+#include <bits/wordsize.h>
+
+#if __WORDSIZE == 32
+# define PREADV preadv64
+# define PREAD __pread64
+# define OFF_T off64_t
+
+# include "preadv.c"
+#endif
diff --git a/sysdeps/posix/pwritev.c b/sysdeps/posix/pwritev.c
new file mode 100644
index 0000000..0b6627d
--- /dev/null
+++ b/sysdeps/posix/pwritev.c
@@ -0,0 +1,108 @@
+/* Copyright (C) 2009 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <errno.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <limits.h>
+#include <stdbool.h>
+#include <sys/param.h>
+#if __WORDSIZE == 64 && !defined PWRITEV
+/* Hide the pwritev64 declaration.  */
+# define pwritev64 __redirect_pwritev64
+#endif
+#include <sys/uio.h>
+#include <bits/wordsize.h>
+
+#ifndef PWRITEV
+# define PWRITEV pwritev
+# define PWRITE __pwrite
+# define OFF_T off_t
+#endif
+
+
+static void
+ifree (char **ptrp)
+{
+  free (*ptrp);
+}
+
+
+/* Read data from file descriptor FD at the given position OFFSET
+   without change the file pointer, and put the result in the buffers
+   described by VECTOR, which is a vector of COUNT 'struct iovec's.
+   The buffers are filled in the order specified.  Operates just like
+   'read' (see <unistd.h>) except that data are put in VECTOR instead
+   of a contiguous buffer.  */
+ssize_t
+PWRITEV (int fd, const struct iovec *vector, int count, OFF_T offset)
+{
+  /* Find the total number of bytes to be read.  */
+  size_t bytes = 0;
+  for (int i = 0; i < count; ++i)
+    {
+      /* Check for ssize_t overflow.  */
+      if (SSIZE_MAX - bytes < vector[i].iov_len)
+	{
+	  __set_errno (EINVAL);
+	  return -1;
+	}
+      bytes += vector[i].iov_len;
+    }
+
+  /* Allocate a temporary buffer to hold the data.  We should normally
+     use alloca since it's faster and does not require synchronization
+     with other threads.  But we cannot if the amount of memory
+     required is too large.  */
+  char *buffer;
+  char *malloced_buffer __attribute__ ((__cleanup__ (ifree))) = NULL;
+  if (__libc_use_alloca (bytes))
+    buffer = (char *) __alloca (bytes);
+  else
+    {
+      malloced_buffer = buffer = (char *) malloc (bytes);
+      if (buffer == NULL)
+	return -1;
+    }
+
+  /* Read the data.  */
+  ssize_t bytes_read = PWRITE (fd, buffer, bytes, offset);
+  if (bytes_read <= 0)
+    return -1;
+
+  /* Copy the data from BUFFER into the memory specified by VECTOR.  */
+  bytes = bytes_read;
+  for (int i = 0; i < count; ++i)
+    {
+      size_t copy = MIN (vector[i].iov_len, bytes);
+
+      (void) memcpy ((void *) vector[i].iov_base, (void *) buffer, copy);
+
+      buffer += copy;
+      bytes -= copy;
+      if (bytes == 0)
+	break;
+    }
+
+  return bytes_read;
+}
+#if __WORDSIZE == 64 && defined pwritev64
+# undef pwritev64
+strong_alias (pwritev, pwritev64)
+#endif
diff --git a/sysdeps/posix/pwritev64.c b/sysdeps/posix/pwritev64.c
new file mode 100644
index 0000000..4948d2e
--- /dev/null
+++ b/sysdeps/posix/pwritev64.c
@@ -0,0 +1,9 @@
+#include <bits/wordsize.h>
+
+#if __WORDSIZE == 32
+# define PWRITEV pwritev64
+# define PWRITE __pwrite64
+# define OFF_T off64_t
+
+# include "pwritev.c"
+#endif
diff --git a/sysdeps/unix/sysv/linux/kernel-features.h b/sysdeps/unix/sysv/linux/kernel-features.h
index 9053df1..a640765 100644
--- a/sysdeps/unix/sysv/linux/kernel-features.h
+++ b/sysdeps/unix/sysv/linux/kernel-features.h
@@ -529,3 +529,10 @@
 #if __LINUX_KERNEL_VERSION >= 0x02061d
 # define __ASSUME_FUTEX_CLOCK_REALTIME	1
 #endif
+
+/* Support for preadv and pwritev was added in 2.6.30.  */
+#if __LINUX_KERNEL_VERSION >= 0x02061e \
+    && (defined __i386__ || defined __x86_64__)
+# define __ASSUME_PREADV	1
+# define __ASSUME_PWRITEV	1
+#endif
diff --git a/sysdeps/unix/sysv/linux/preadv.c b/sysdeps/unix/sysv/linux/preadv.c
new file mode 100644
index 0000000..e2f8238
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/preadv.c
@@ -0,0 +1,88 @@
+/* Copyright (C) 2009 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <errno.h>
+#include <stddef.h>
+#include <sys/param.h>
+#if __WORDSIZE == 64
+/* Hide the preadv64 declaration.  */
+# define preadv64 __redirect_preadv64
+#endif
+#include <sys/uio.h>
+
+#include <sysdep-cancel.h>
+#include <sys/syscall.h>
+#include <kernel-features.h>
+
+#ifndef PREADV
+# define PREADV preadv
+# define PREADV_REPLACEMENT __atomic_preadv_replacement
+# define PREAD __pread
+# define OFF_T off_t
+#endif
+
+static ssize_t PREADV_REPLACEMENT (int, __const struct iovec *,
+				   int, OFF_T) internal_function;
+
+
+ssize_t
+PREADV (fd, vector, count, offset)
+     int fd;
+     const struct iovec *vector;
+     int count;
+     OFF_T offset;
+{
+#ifdef __NR_preadv
+  ssize_t result;
+
+  if (SINGLE_THREAD_P)
+    result = INLINE_SYSCALL (preadv, 5, fd, vector, count, offset >> 32,
+			     offset & 0xffffffff);
+  else
+    {
+      int oldtype = LIBC_CANCEL_ASYNC ();
+
+      result = INLINE_SYSCALL (preadv, 5, fd, vector, count, offset >> 32,
+			       offset & 0xffffffff);
+
+      LIBC_CANCEL_RESET (oldtype);
+    }
+# ifdef __ASSUME_PREADV
+  return result;
+# endif
+#endif
+
+#ifndef __ASSUME_PREADV
+# ifdef __NR_preadv
+  if (result >= 0 || errno != ENOSYS)
+    return result;
+# endif
+
+  return PREADV_REPLACEMENT (fd, vector, count, offset);
+#endif
+}
+#if __WORDSIZE == 64
+# undef preadv64
+strong_alias (preadv, preadv64)
+#endif
+
+#ifndef __ASSUME_PREADV
+# undef PREADV
+# define PREADV static internal_function PREADV_REPLACEMENT
+# include <sysdeps/posix/preadv.c>
+#endif
diff --git a/sysdeps/unix/sysv/linux/preadv64.c b/sysdeps/unix/sysv/linux/preadv64.c
new file mode 100644
index 0000000..739df00
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/preadv64.c
@@ -0,0 +1,6 @@
+#define PREADV preadv64
+#define PREADV_REPLACEMENT __atomic_preadv64_replacement
+#define PREAD __pread64
+#define OFF_T off64_t
+
+#include "preadv.c"
diff --git a/sysdeps/unix/sysv/linux/pwritev.c b/sysdeps/unix/sysv/linux/pwritev.c
new file mode 100644
index 0000000..df430ff
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/pwritev.c
@@ -0,0 +1,88 @@
+/* Copyright (C) 2009 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <errno.h>
+#include <stddef.h>
+#include <sys/param.h>
+#if __WORDSIZE == 64 && !defined PWRITEV
+/* Hide the pwritev64 declaration.  */
+# define pwritev64 __redirect_pwritev64
+#endif
+#include <sys/uio.h>
+
+#include <sysdep-cancel.h>
+#include <sys/syscall.h>
+#include <kernel-features.h>
+
+#ifndef PWRITEV
+# define PWRITEV pwritev
+# define PWRITEV_REPLACEMENT __atomic_pwritev_replacement
+# define PWRITE __pwrite
+# define OFF_T off_t
+#endif
+
+static ssize_t PWRITEV_REPLACEMENT (int, __const struct iovec *,
+				    int, OFF_T) internal_function;
+
+
+ssize_t
+PWRITEV (fd, vector, count, offset)
+     int fd;
+     const struct iovec *vector;
+     int count;
+     OFF_T offset;
+{
+#ifdef __NR_pwritev
+  ssize_t result;
+
+  if (SINGLE_THREAD_P)
+    result = INLINE_SYSCALL (pwritev, 5, fd, vector, count, offset >> 32,
+			     offset & 0xffffffff);
+  else
+    {
+      int oldtype = LIBC_CANCEL_ASYNC ();
+
+      result = INLINE_SYSCALL (pwritev, 5, fd, vector, count, offset >> 32,
+			       offset & 0xffffffff);
+
+      LIBC_CANCEL_RESET (oldtype);
+    }
+# ifdef __ASSUME_PWRITEV
+  return result;
+# endif
+#endif
+
+#ifndef __ASSUME_PWRITEV
+# ifdef __NR_pwritev
+  if (result >= 0 || errno != ENOSYS)
+    return result;
+# endif
+
+  return PWRITEV_REPLACEMENT (fd, vector, count, offset);
+#endif
+}
+#if __WORDSIZE == 64 && defined pwritev64
+# undef pwritev64
+strong_alias (pwritev, pwritev64)
+#endif
+
+#ifndef __ASSUME_PWRITEV
+# undef PWRITEV
+# define PWRITEV static internal_function PWRITEV_REPLACEMENT
+# include <sysdeps/posix/pwritev.c>
+#endif
diff --git a/sysdeps/unix/sysv/linux/pwritev64.c b/sysdeps/unix/sysv/linux/pwritev64.c
new file mode 100644
index 0000000..1e8168f
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/pwritev64.c
@@ -0,0 +1,6 @@
+#define PWRITEV pwritev64
+#define PWRITEV_REPLACEMENT __atomic_pwritev64_replacement
+#define PWRITE __pwrite64
+#define OFF_T off64_t
+
+#include "pwritev.c"
diff --git a/sysdeps/unix/sysv/linux/wordsize-64/preadv64.c b/sysdeps/unix/sysv/linux/wordsize-64/preadv64.c
new file mode 100644
index 0000000..fd9320c
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/wordsize-64/preadv64.c
@@ -0,0 +1 @@
+/* Empty since the preadv syscall is equivalent.  */
diff --git a/sysdeps/unix/sysv/linux/wordsize-64/pwritev64.c b/sysdeps/unix/sysv/linux/wordsize-64/pwritev64.c
new file mode 100644
index 0000000..8b72a29
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/wordsize-64/pwritev64.c
@@ -0,0 +1 @@
+/* Empty since the pwritev syscall is equivalent.  */