NFSD: Use vfs_iocb_iter_write()

Refactor: Enable the use of IOCB flags to control NFSD's individual
write operations. This allows the eventual use of atomic, uncached,
direct, or asynchronous writes.

Suggested-by: NeilBrown <neil@brown.name>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: NeilBrown <neil@brown.name>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 3e21599294fe149a5e03364d5d597d9bbc238640..ee78b6fb17098b788b07f5cd90598e678244b57e 100644 (file)
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -1173,15 +1173,14 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp,
        struct nfsd_net         *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
        struct file             *file = nf->nf_file;
        struct super_block      *sb = file_inode(file)->i_sb;
+       struct kiocb            kiocb;
        struct svc_export       *exp;
        struct iov_iter         iter;
        errseq_t                since;
        __be32                  nfserr;
        int                     host_err;
-       loff_t                  pos = offset;
        unsigned long           exp_op_flags = 0;
        unsigned int            pflags = current->flags;
-       rwf_t                   flags = 0;
        bool                    restore_flags = false;
        unsigned int            nvecs;
 
@@ -1207,16 +1206,17 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp,
 
        if (!EX_ISSYNC(exp))
                stable = NFS_UNSTABLE;
-
+       init_sync_kiocb(&kiocb, file);
+       kiocb.ki_pos = offset;
        if (stable && !fhp->fh_use_wgather)
-               flags |= RWF_SYNC;
+               kiocb.ki_flags |= IOCB_DSYNC;
 
        nvecs = xdr_buf_to_bvec(rqstp->rq_bvec, rqstp->rq_maxpages, payload);
        iov_iter_bvec(&iter, ITER_SOURCE, rqstp->rq_bvec, nvecs, *cnt);
        since = READ_ONCE(file->f_wb_err);
        if (verf)
                nfsd_copy_write_verifier(verf, nn);
-       host_err = vfs_iter_write(file, &iter, &pos, flags);
+       host_err = vfs_iocb_iter_write(file, &kiocb, &iter);
        if (host_err < 0) {
                commit_reset_write_verifier(nn, rqstp, host_err);
                goto out_nfserr;