2ef47eb1 (NFS: Fix use of nfs_attr_use_mounted_on_fileid()) was a good
start to fixing a circular directory structure warning for NFS v4
"junctioned" mountpoints. Unfortunately, further testing continued to
generate this error.
My server is configured like this:
anna@nfsd ~ % df
Filesystem Size Used Avail Use% Mounted on
/dev/vda1 9.1G 2.0G 6.5G 24% /
/dev/vdc1 1014M 33M 982M 4% /exports
/dev/vdc2 1014M 33M 982M 4% /exports/vol1
/dev/vdc3 1014M 33M 982M 4% /exports/vol1/vol2
anna@nfsd ~ % cat /etc/exports
/exports/ *(rw,async,no_subtree_check,no_root_squash)
/exports/vol1/ *(rw,async,no_subtree_check,no_root_squash)
/exports/vol1/vol2 *(rw,async,no_subtree_check,no_root_squash)
I've been running chown across the entire mountpoint twice in a row to
hit this problem. The first run succeeds, but the second one fails with
the circular directory warning along with:
anna@client ~ % dmesg
[Apr 3 14:28] NFS: server 192.168.100.204 error: fileid changed
fsid 0:39: expected fileid 0x100080, got 0x80
WHere 0x80 is the mountpoint's fileid and 0x100080 is the mounted-on
fileid.
This patch fixes the issue by requesting an updated mounted-on fileid
from the server during nfs_update_inode(), and then checking that the
fileid stored in the nfs_inode matches either the fileid or mounted-on
fileid returned by the server.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
ea96d1ecbe