diff options
| author | J. Bruce Fields <bfields@redhat.com> | 2020-11-30 17:46:14 -0500 |
|---|---|---|
| committer | Chuck Lever <chuck.lever@oracle.com> | 2020-12-09 09:39:37 -0500 |
| commit | 70b87f77294d16d3e567056ba4c9ee2b091a5b50 (patch) | |
| tree | 557e788075d69a9eb9248a8cc6aeb3486dd5c348 /fs/nfsd/nfs3xdr.c | |
| parent | 4a9d81caf841cd2c0ae36abec9c2963bf21d0284 (diff) | |
nfsd: only call inode_query_iversion in the I_VERSION case
inode_query_iversion() can modify i_version. Depending on the exported
filesystem, that may not be safe. For example, if you're re-exporting
NFS, NFS stores the server's change attribute in i_version and does not
expect it to be modified locally. This has been observed causing
unnecessary cache invalidations.
The way a filesystem indicates that it's OK to call
inode_query_iverson() is by setting SB_I_VERSION.
So, move the I_VERSION check out of encode_change(), where it's used
only in GETATTR responses, to nfsd4_change_attribute(), which is
also called for pre- and post- operation attributes.
(Note we could also pull the NFSEXP_V4ROOT case into
nfsd4_change_attribute() as well. That would actually be a no-op,
since pre/post attrs are only used for metadata-modifying operations,
and V4ROOT exports are read-only. But we might make the change in
the future just for simplicity.)
Reported-by: Daire Byrne <daire@dneg.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Diffstat (limited to 'fs/nfsd/nfs3xdr.c')
| -rw-r--r-- | fs/nfsd/nfs3xdr.c | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/fs/nfsd/nfs3xdr.c b/fs/nfsd/nfs3xdr.c index a6718b952975..4599de24ef1a 100644 --- a/fs/nfsd/nfs3xdr.c +++ b/fs/nfsd/nfs3xdr.c @@ -291,14 +291,13 @@ void fill_post_wcc(struct svc_fh *fhp) printk("nfsd: inode locked twice during operation.\n"); err = fh_getattr(fhp, &fhp->fh_post_attr); - fhp->fh_post_change = nfsd4_change_attribute(&fhp->fh_post_attr, - d_inode(fhp->fh_dentry)); if (err) { fhp->fh_post_saved = false; - /* Grab the ctime anyway - set_change_info might use it */ fhp->fh_post_attr.ctime = d_inode(fhp->fh_dentry)->i_ctime; } else fhp->fh_post_saved = true; + fhp->fh_post_change = nfsd4_change_attribute(&fhp->fh_post_attr, + d_inode(fhp->fh_dentry)); } /* |