NFSD add vfs_fsync after async copy is done

Currently, the server does all copies as NFS_UNSTABLE. For synchronous
copies linux client will append a COMMIT to the COPY compound but for
async copies it does not (because COMMIT needs to be done after all
bytes are copied and not as a reply to the COPY operation).

However, in order to save the client doing a COMMIT as a separate
rpc, the server can reply back with NFS_FILE_SYNC copy. This patch
proposed to add vfs_fsync() call at the end of the async copy.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 426b232ca9fd90b98d1cd28c28a9191db5fb1e2c..48c0992cb65cd8592b43af5e3f9674b0680c410f 100644 (file)
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -1375,7 +1375,8 @@ static const struct nfsd4_callback_ops nfsd4_cb_offload_ops = {
 
 static void nfsd4_init_copy_res(struct nfsd4_copy *copy, bool sync)
 {
-       copy->cp_res.wr_stable_how = NFS_UNSTABLE;
+       copy->cp_res.wr_stable_how =
+               copy->committed ? NFS_FILE_SYNC : NFS_UNSTABLE;
        copy->cp_synchronous = sync;
        gen_boot_verifier(&copy->cp_res.wr_verifier, copy->cp_clp->net);
 }
@@ -1386,6 +1387,7 @@ static ssize_t _nfsd_copy_file_range(struct nfsd4_copy *copy)
        u64 bytes_total = copy->cp_count;
        u64 src_pos = copy->cp_src_pos;
        u64 dst_pos = copy->cp_dst_pos;
+       __be32 status;
 
        /* See RFC 7862 p.67: */
        if (bytes_total == 0)
@@ -1403,6 +1405,16 @@ static ssize_t _nfsd_copy_file_range(struct nfsd4_copy *copy)
                src_pos += bytes_copied;
                dst_pos += bytes_copied;
        } while (bytes_total > 0 && !copy->cp_synchronous);
+       /* for a non-zero asynchronous copy do a commit of data */
+       if (!copy->cp_synchronous && copy->cp_res.wr_bytes_written > 0) {
+               down_write(&copy->nf_dst->nf_rwsem);
+               status = vfs_fsync_range(copy->nf_dst->nf_file,
+                                        copy->cp_dst_pos,
+                                        copy->cp_res.wr_bytes_written, 0);
+               up_write(&copy->nf_dst->nf_rwsem);
+               if (!status)
+                       copy->committed = true;
+       }
        return bytes_copied;
 }
 

diff --git a/fs/nfsd/xdr4.h b/fs/nfsd/xdr4.h
index a7c425254fee53c6e8b1b7fe10386f2dc0aaa93e..3e4052e3bd50eebf43327842fd9822deb36285e1 100644 (file)
--- a/fs/nfsd/xdr4.h
+++ b/fs/nfsd/xdr4.h
@@ -567,6 +567,7 @@ struct nfsd4_copy {
        struct vfsmount         *ss_mnt;
        struct nfs_fh           c_fh;
        nfs4_stateid            stateid;
+       bool                    committed;
 };
 
 struct nfsd4_seek {