diff options
| author | J. Bruce Fields <bfields@citi.umich.edu> | 2009-04-16 17:33:25 -0400 |
|---|---|---|
| committer | J. Bruce Fields <bfields@citi.umich.edu> | 2009-04-29 11:35:49 -0400 |
| commit | c654b8a9cba6002aad1c01919e4928a79a4a6dcf (patch) | |
| tree | fee411bb42ec86e72a9e843529551e559c1f2749 /include/linux/nfsd/xdr4.h | |
| parent | 3352d2c2d0540955a7bbb3421a28330af7f9d79c (diff) | |
nfsd: support ext4 i_version
ext4 supports a real NFSv4 change attribute, which is bumped whenever
the ctime would be updated, including times when two updates arrive
within a jiffy of each other. (Note that although ext4 has space for
nanosecond-precision ctime, the real resolution is lower: it actually
uses jiffies as the time-source.) This ensures clients will invalidate
their caches when they need to.
There is some fear that keeping the i_version up-to-date could have
performance drawbacks, so for now it's turned on only by a mount option.
We hope to do something better eventually.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: Theodore Tso <tytso@mit.edu>
Diffstat (limited to 'include/linux/nfsd/xdr4.h')
| -rw-r--r-- | include/linux/nfsd/xdr4.h | 17 |
1 files changed, 13 insertions, 4 deletions
diff --git a/include/linux/nfsd/xdr4.h b/include/linux/nfsd/xdr4.h index f80d6013fdc..d0f050f01ec 100644 --- a/include/linux/nfsd/xdr4.h +++ b/include/linux/nfsd/xdr4.h @@ -64,10 +64,13 @@ static inline bool nfsd4_has_session(struct nfsd4_compound_state *cs) struct nfsd4_change_info { u32 atomic; + bool change_supported; u32 before_ctime_sec; u32 before_ctime_nsec; + u64 before_change; u32 after_ctime_sec; u32 after_ctime_nsec; + u64 after_change; }; struct nfsd4_access { @@ -503,10 +506,16 @@ set_change_info(struct nfsd4_change_info *cinfo, struct svc_fh *fhp) { BUG_ON(!fhp->fh_pre_saved || !fhp->fh_post_saved); cinfo->atomic = 1; - cinfo->before_ctime_sec = fhp->fh_pre_ctime.tv_sec; - cinfo->before_ctime_nsec = fhp->fh_pre_ctime.tv_nsec; - cinfo->after_ctime_sec = fhp->fh_post_attr.ctime.tv_sec; - cinfo->after_ctime_nsec = fhp->fh_post_attr.ctime.tv_nsec; + cinfo->change_supported = IS_I_VERSION(fhp->fh_dentry->d_inode); + if (cinfo->change_supported) { + cinfo->before_change = fhp->fh_pre_change; + cinfo->after_change = fhp->fh_post_change; + } else { + cinfo->before_ctime_sec = fhp->fh_pre_ctime.tv_sec; + cinfo->before_ctime_nsec = fhp->fh_pre_ctime.tv_nsec; + cinfo->after_ctime_sec = fhp->fh_post_attr.ctime.tv_sec; + cinfo->after_ctime_nsec = fhp->fh_post_attr.ctime.tv_nsec; + } } int nfs4svc_encode_voidres(struct svc_rqst *, __be32 *, void *); |