Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1391089

[PATCH 4/6] statx: NFS: Return enhanced file attributes

From David Howells <dhowells@redhat.com>
Newsgroups linux.kernel
Subject [PATCH 4/6] statx: NFS: Return enhanced file attributes
Date 2016-04-29 15:00 +0200
Message-ID <rtgbv-69i-13@gated-at.bofh.it> (permalink)
References <rtgbv-69i-7@gated-at.bofh.it>
Organization Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903

Show all headers | View raw

Return enhanced file atrributes from the NFS filesystem.  This includes the
following:

 (1) The change attribute as st_version if NFSv4.

 (2) STATX_INFO_AUTOMOUNT and STATX_INFO_FABRICATED are set on referral or
     submount directories that are automounted upon.  NFS shows one
     directory with a different FSID, but the local filesystem has two: the
     mountpoint directory and the root of the filesystem mounted upon it.

 (3) STATX_INFO_REMOTE is set on files acquired over NFS.

 (4) STATX_IOC_FLAGS is set and if the atime is unavailable on a file,
     st_ioc_flags will have FL_NOATIME_FL set in it.

Furthermore, what nfs_getattr() does can be controlled as follows:

 (1) If AT_NO_ATTR_SYNC is indicated then this will suppress the flushing
     of outstanding writes and the rereading of the inode's attributes with
     the server as detailed below.

 (2) Otherwise:

     (a) If AT_FORCE_ATTR_SYNC is indicated, or mtime, ctime or
     	 data_version (NFSv4 only) are requested then the outstanding
     	 writes will be written to the server first.

     (b) The inode's attributes will be reread from the server:

     	 (i) if AT_FORCE_ATTR_SYNC is indicated;

        (ii) if atime is requested (and atime updating is not suppressed by
     	     a mount flag); or

       (iii) if the cached attributes have expired;

If the inode isn't synchronised, then the cached attributes will be used -
even if expired - without reference to the server.

Example output:

	[root@andromeda ~]# ./samples/statx/test-statx /warthog/
	statx(/warthog/) = 0
	results=37ef
	  Size: 4096            Blocks: 8          IO Block: 1048576  directory
	Device: 00:26           Inode: 2           Links: 122
	Access: (3777/drwxrwxrwx)  Uid:     0   Gid:  4041
	Access: 2015-10-30 16:15:41.730925545+0000
	Modify: 2015-10-07 10:33:19.896108112+0100
	Change: 2015-10-07 10:33:19.896108112+0100
	Data version: 5614e6df35698650h
	Inode flags: 00000000 (-------- -------- -------- --------)
	Information: 00000010 (-------- -------- -------- ---r----)
	IO-blocksize: blksize=1048576

Note that the NFS4 protocol potentially provides a creation time that could
be passed through this interface and system, hidden and archive values that
could be passed as IOC flags.  There is also a backup time that could be
added.

Signed-off-by: David Howells <dhowells@redhat.com>
---

 fs/nfs/inode.c |   41 ++++++++++++++++++++++++++++++++++-------
 1 file changed, 34 insertions(+), 7 deletions(-)

diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 738c84a42eb0..8637236bca0c 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -655,12 +655,23 @@ static bool nfs_need_revalidate_inode(struct inode *inode)
 int nfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
 {
 	struct inode *inode = d_inode(dentry);
-	int need_atime = NFS_I(inode)->cache_validity & NFS_INO_INVALID_ATIME;
+	bool force_sync = stat->query_flags & AT_FORCE_ATTR_SYNC;
+	bool suppress_sync = stat->query_flags & AT_NO_ATTR_SYNC;
+	bool need_atime = NFS_I(inode)->cache_validity & NFS_INO_INVALID_ATIME;
 	int err = 0;
 
 	trace_nfs_getattr_enter(inode);
-	/* Flush out writes to the server in order to update c/mtime.  */
-	if (S_ISREG(inode->i_mode)) {
+
+	if (NFS_SERVER(inode)->nfs_client->rpc_ops->version < 4)
+		stat->request_mask &= ~STATX_VERSION;
+
+	/* Flush out writes to the server in order to update c/mtime or data
+	 * version if the user wants them.
+	 */
+	if (S_ISREG(inode->i_mode) && !suppress_sync &&
+	    (force_sync || (stat->request_mask &
+			    (STATX_MTIME | STATX_CTIME | STATX_VERSION)))
+	    ) {
 		inode_lock(inode);
 		err = nfs_sync_inode(inode);
 		inode_unlock(inode);
@@ -677,11 +688,13 @@ int nfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
 	 *  - NFS never sets MS_NOATIME or MS_NODIRATIME so there is
 	 *    no point in checking those.
 	 */
- 	if ((mnt->mnt_flags & MNT_NOATIME) ||
- 	    ((mnt->mnt_flags & MNT_NODIRATIME) && S_ISDIR(inode->i_mode)))
-		need_atime = 0;
+	if (!(stat->request_mask & STATX_ATIME) ||
+	    (mnt->mnt_flags & MNT_NOATIME) ||
+	    ((mnt->mnt_flags & MNT_NODIRATIME) && S_ISDIR(inode->i_mode)))
+		need_atime = false;
 
-	if (need_atime || nfs_need_revalidate_inode(inode)) {
+	if (!suppress_sync &&
+	    (force_sync || need_atime || nfs_need_revalidate_inode(inode))) {
 		struct nfs_server *server = NFS_SERVER(inode);
 
 		if (server->caps & NFS_CAP_READDIRPLUS)
@@ -694,6 +707,20 @@ int nfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
 		if (S_ISDIR(inode->i_mode))
 			stat->blksize = NFS_SERVER(inode)->dtsize;
 	}
+
+	generic_fillattr(inode, stat);
+	stat->ino = nfs_compat_user_ino64(NFS_FILEID(inode));
+
+	if (stat->request_mask & STATX_VERSION) {
+		stat->version = inode->i_version;
+		stat->result_mask |= STATX_VERSION;
+	}
+
+	if (IS_AUTOMOUNT(inode))
+		stat->information |= STATX_INFO_FABRICATED;
+
+	stat->information |= STATX_INFO_REMOTE;
+
 out:
 	trace_nfs_getattr_exit(inode, err);
 	return err;

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[RFC][PATCH 0/6] Enhanced file stat system call David Howells <dhowells@redhat.com> - 2016-04-29 15:00 +0200
  [PATCH 4/6] statx: NFS: Return enhanced file attributes David Howells <dhowells@redhat.com> - 2016-04-29 15:00 +0200
    Re: [PATCH 4/6] statx: NFS: Return enhanced file attributes Andreas Dilger <adilger@dilger.ca> - 2016-05-03 00:50 +0200
  [PATCH 6/6] statx: CIFS: Return enhanced attributes David Howells <dhowells@redhat.com> - 2016-04-29 15:00 +0200
  [PATCH 3/6] statx: Ext4: Return enhanced file attributes David Howells <dhowells@redhat.com> - 2016-04-29 15:00 +0200
    Re: [PATCH 3/6] statx: Ext4: Return enhanced file attributes Andreas Dilger <adilger@dilger.ca> - 2016-05-03 00:50 +0200
      Re: [PATCH 3/6] statx: Ext4: Return enhanced file attributes David Howells <dhowells@redhat.com> - 2016-05-03 22:30 +0200
    Re: [PATCH 3/6] statx: Ext4: Return enhanced file attributes Christoph Hellwig <hch@infradead.org> - 2016-05-08 10:40 +0200
  [PATCH 5/6] statx: Make windows attributes available for CIFS,  NTFS and FAT to use David Howells <dhowells@redhat.com> - 2016-04-29 15:10 +0200
    Re: [PATCH 5/6] statx: Make windows attributes available for CIFS, NTFS and FAT to use Andreas Dilger <adilger@dilger.ca> - 2016-05-03 01:00 +0200
      Re: [PATCH 5/6] statx: Make windows attributes available for CIFS, NTFS and FAT to use David Howells <dhowells@redhat.com> - 2016-05-03 22:30 +0200
    Re: [PATCH 5/6] statx: Make windows attributes available for CIFS,  NTFS and FAT to use Christoph Hellwig <hch@infradead.org> - 2016-05-08 10:40 +0200
  [PATCH 2/6] statx: AFS: Return enhanced file attributes David Howells <dhowells@redhat.com> - 2016-04-29 15:20 +0200
  Re: [RFC][PATCH 0/6] Enhanced file stat system call Jeff Layton <jlayton@poochiereds.net> - 2016-04-30 23:10 +0200
  Re: [PATCH 1/6] statx: Add a system call to make enhanced file info available David Howells <dhowells@redhat.com> - 2016-05-03 18:00 +0200
  Re: [RFC][PATCH 0/6] Enhanced file stat system call Arnd Bergmann <arnd@arndb.de> - 2016-05-04 15:50 +0200
    Re: [RFC][PATCH 0/6] Enhanced file stat system call Steve French <smfrench@gmail.com> - 2016-05-06 04:10 +0200
      Re: [RFC][PATCH 0/6] Enhanced file stat system call Arnd Bergmann <arnd@arndb.de> - 2016-05-09 15:10 +0200
  Re: [PATCH 1/6] statx: Add a system call to make enhanced file info  available Dave Chinner <david@fromorbit.com> - 2016-05-05 01:00 +0200
    Re: [PATCH 1/6] statx: Add a system call to make enhanced file info available NeilBrown <nfbrown@novell.com> - 2016-05-05 02:20 +0200
      Re: [PATCH 1/6] statx: Add a system call to make enhanced file info  available Jeff Layton <jlayton@poochiereds.net> - 2016-05-05 21:50 +0200
        Re: [PATCH 1/6] statx: Add a system call to make enhanced file info available David Howells <dhowells@redhat.com> - 2016-05-05 22:10 +0200
          Re: [PATCH 1/6] statx: Add a system call to make enhanced file info  available Dave Chinner <david@fromorbit.com> - 2016-05-06 03:50 +0200
        Re: [PATCH 1/6] statx: Add a system call to make enhanced file info  available bfields@fieldses.org (J. Bruce Fields) - 2016-05-06 20:10 +0200
    Re: [PATCH 1/6] statx: Add a system call to make enhanced file info  available bfields@fieldses.org (J. Bruce Fields) - 2016-05-06 20:30 +0200
      Re: [PATCH 1/6] statx: Add a system call to make enhanced file info  available Dave Chinner <david@fromorbit.com> - 2016-05-09 03:50 +0200
        Re: [PATCH 1/6] statx: Add a system call to make enhanced file info  available "J. Bruce Fields" <bfields@fieldses.org> - 2016-05-09 04:50 +0200
  Re: [PATCH 1/6] statx: Add a system call to make enhanced file info available NeilBrown <nfbrown@novell.com> - 2016-05-05 02:00 +0200
  Re: [PATCH 1/6] statx: Add a system call to make enhanced file info  available Christoph Hellwig <hch@infradead.org> - 2016-05-08 10:40 +0200
    Re: [PATCH 1/6] statx: Add a system call to make enhanced file info  available Jeff Layton <jlayton@poochiereds.net> - 2016-05-09 14:10 +0200
      Re: [PATCH 1/6] statx: Add a system call to make enhanced file info  available Christoph Hellwig <hch@infradead.org> - 2016-05-10 09:10 +0200
        Re: [PATCH 1/6] statx: Add a system call to make enhanced file info  available Jeff Layton <jlayton@poochiereds.net> - 2016-05-10 15:30 +0200
    Re: [PATCH 1/6] statx: Add a system call to make enhanced file info available David Howells <dhowells@redhat.com> - 2016-05-09 15:00 +0200
      Re: [PATCH 1/6] statx: Add a system call to make enhanced file info available David Howells <dhowells@redhat.com> - 2016-05-09 15:10 +0200
      Re: [PATCH 1/6] statx: Add a system call to make enhanced file info  available Trond Myklebust <trondmy@primarydata.com> - 2016-05-09 15:40 +0200
      Re: [PATCH 1/6] statx: Add a system call to make enhanced file info  available Christoph Hellwig <hch@infradead.org> - 2016-05-10 09:10 +0200
        Re: [PATCH 1/6] statx: Add a system call to make enhanced file info available David Howells <dhowells@redhat.com> - 2016-05-10 10:30 +0200
          Re: [PATCH 1/6] statx: Add a system call to make enhanced file info  available Christoph Hellwig <hch@infradead.org> - 2016-05-12 11:20 +0200
    Re: [PATCH 1/6] statx: Add a system call to make enhanced file info available David Howells <dhowells@redhat.com> - 2016-05-09 15:40 +0200
      Re: [PATCH 1/6] statx: Add a system call to make enhanced file info  available Christoph Hellwig <hch@infradead.org> - 2016-05-10 09:10 +0200
        Re: [PATCH 1/6] statx: Add a system call to make enhanced file info available David Howells <dhowells@redhat.com> - 2016-05-10 10:50 +0200
          Re: [PATCH 1/6] statx: Add a system call to make enhanced file info  available Christoph Hellwig <hch@infradead.org> - 2016-05-12 11:20 +0200
    Re: [PATCH 1/6] statx: Add a system call to make enhanced file info available David Howells <dhowells@redhat.com> - 2016-05-09 15:50 +0200

csiph-web