Bug#480354: sendfile support missing in aufs

[Laszlo Bako-Szabo <lazics@gmail.com>]

Package: linux-image-2.6.24-1-amd64
Severity: important


aufs no longer has the sendfile capability, which seems to be 
because the kernel is missing a patch, that is needed for 2.6.23+ kernels.
( http://aufs.cvs.sourceforge.net/aufs/aufs/patch/splice-2.6.23.patch?view=markup )
The function returns with 'Invalid argument' if I try to use it 
on an aufs filesystem. The last working kernel is 2.6.22-3.

Tests were made with lighttpd and a small test program (attached).


-- Package-specific info:

-- System Information:
Debian Release: lenny/sid
  APT prefers testing
  APT policy: (990, 'testing'), (500, 'stable')
Architecture: amd64 (x86_64)

Kernel: Linux 2.6.22-3-amd64 (SMP w/2 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/bash

/* 
 * SENDFILE TEST 
 *
 * mkdir -p /tmp/aufs /tmp/aufs1; echo "test" > /tmp/aufs1/test.txt; mount -t aufs none /tmp/aufs -o rw,br:/tmp/aufs1
 *
 * ./sendfile-test2 /tmp/aufs/test.txt
 *
 */

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/sendfile.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <netinet/in.h>

int main(int argc, char **argv)
{
  int port = 54321, sock_srv, sock_clnt, fd, addrlen;
  struct sockaddr_in addr;	 off_t offset = 0;
  char buf[1];

  if (argc!=2) { printf("Usage: %s <file-on-aufs>\n", argv[0]); }

  if ( (sock_srv = socket(AF_INET, SOCK_DGRAM, 0)) == -1) { fprintf(stderr, "server socket error: %s\n", strerror(errno)); exit(1); }
  memset(&addr, 0, sizeof(addr)); addr.sin_family = AF_INET;  addr.sin_addr.s_addr = inet_addr("127.0.0.1");  addr.sin_port = htons(port);
  if ( bind(sock_srv, (struct sockaddr *)&addr, sizeof(addr)) == -1 ) { fprintf(stderr, "server bind error: %s\n", strerror(errno)); exit(1); }

  if ( (sock_clnt = socket(AF_INET, SOCK_DGRAM, 0)) == -1) { fprintf(stderr, "client socket error: %s\n", strerror(errno)); exit(1); }
  if ( connect(sock_clnt, (struct sockaddr *)&addr, sizeof(addr)) == -1 ) { fprintf(stderr, "client connect error: %s\n", strerror(errno)); exit(1); }

  if ( (fd = open(argv[1], O_RDONLY)) == -1) { fprintf(stderr, "open error: %s\n",  strerror(errno)); exit(1); }
  offset = 0;
  if ( sendfile (sock_clnt, fd, &offset, 1) == -1) { fprintf(stderr, "sendfile error: %s\n",  strerror(errno)); exit(1); }
  if ( read(sock_srv, buf, 1) < 1 ) { fprintf(stderr, "read error: %s\n", strerror(errno)); exit(1); }
  printf("sendfile seems OK!\n");
  close(fd); close(sock_srv); close(sock_clnt);  return 0;
}