[PATCH v2 0/3] xfs: add O_TMPFILE support

[Zhi Yong Wu]

From: Zhi Yong Wu <wuzhy at linux.vnet.ibm.com>

HI, folks

  It's time to post the latest revision out, welcome to any constructive comment, thanks.

  If anyone is interested in playing with it, you can get this patchset from my dev git on github:
  git://github.com/wuzhy/kernel.git xfs_tmpfile

  The patchset was tested against the code snippet from Andy Lutomirski and other test cases:
  http://lwn.net/Articles/562296/
  If you have any other better test cases, please let me know, thanks.

#include <stdio.h>
#include <err.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>

#define __O_TMPFILE 020000000
#define O_DIRECTORY 0200000
#define O_TMPFILE (__O_TMPFILE | O_DIRECTORY)
#define AT_EMPTY_PATH 0x1000

int main(int argc, char **argv)
{
   char buf[128];

   if (argc != 3)
     errx(1, "Usage: flinktest PATH linkat|proc");

   int fd = open(".", O_TMPFILE | O_RDWR, 0600);
   if (fd == -1)
     err(1, "O_TMPFILE");
   else
     printf("fd #: %d\n", fd);

   write(fd, "test", 4);

   if (!strcmp(argv[2], "linkat")) {
     if (linkat(fd, "", AT_FDCWD, argv[1], AT_EMPTY_PATH) != 0)
       err(1, "linkat");
   } else if (!strcmp(argv[2], "proc")) {
     sprintf(buf, "/proc/self/fd/%d", fd);
     if (linkat(AT_FDCWD, buf, AT_FDCWD, argv[1], AT_SYMLINK_FOLLOW) != 0)
       err(1, "linkat");
   } else {
     errx(1, "invalid mode");
   }

   return 0;
}

Changelog from v1:
 - Fixed one chunk of the comments from Christoph Hellwig and Jeff Liu.

v1:
 - Addressed the comments from Dave Chinner and Christoph Hellwig.

Zhi Yong Wu (3):
  xfs: factor prid related codes into xfs_get_initial_prid()
  xfs: add O_TMPFILE support
  xfs: allow linkat() on O_TMPFILE files

 fs/xfs/xfs_inode.c      |  123 ++++++++++++++++++++++++++++++++++++++++++++--
 fs/xfs/xfs_inode.h      |   12 +++++
 fs/xfs/xfs_iops.c       |   16 ++++++
 fs/xfs/xfs_shared.h     |    4 +-
 fs/xfs/xfs_symlink.c    |    5 +--
 fs/xfs/xfs_trans_resv.c |   55 +++++++++++++++++++--
 fs/xfs/xfs_trans_resv.h |    3 +
 7 files changed, 203 insertions(+), 15 deletions(-)

-- 
1.7.6.5