NFS append COMMIT after synchronous COPY

Instead of messing with the commit path which has been causing issues,
add a COMMIT op after the COPY and ask for stable copies in the first
space.

It saves a round trip, since after the COPY, the client sends a COMMIT
anyway.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

5 files changed, 36 insertions, 39 deletions

diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 31b26cf1b476..e9b4c3320e37 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -495,7 +495,6 @@ void nfs_mark_request_commit(struct nfs_page *req,
                              u32 ds_commit_idx);
 int nfs_write_need_commit(struct nfs_pgio_header *);
 void nfs_writeback_update_inode(struct nfs_pgio_header *hdr);
-int nfs_commit_file(struct file *file, struct nfs_write_verifier *verf);
 int nfs_generic_commit_list(struct inode *inode, struct list_head *head,
                             int how, struct nfs_commit_info *cinfo);
 void nfs_retry_commit(struct list_head *page_list,
diff --git a/fs/nfs/nfs42proc.c b/fs/nfs/nfs42proc.c
index 87f5b7b971ca..929d09a5310a 100644
--- a/fs/nfs/nfs42proc.c
+++ b/fs/nfs/nfs42proc.c
@@ -167,23 +167,29 @@ static ssize_t _nfs42_proc_copy(struct file *src,
         if (status)
                 return status;
 
+        res->commit_res.verf = kzalloc(sizeof(struct nfs_writeverf), GFP_NOFS);
+        if (!res->commit_res.verf)
+                return -ENOMEM;
         status = nfs4_call_sync(server->client, server, &msg,
                                 &args->seq_args, &res->seq_res, 0);
         if (status == -ENOTSUPP)
                 server->caps &= ~NFS_CAP_COPY;
         if (status)
-                return status;
+                goto out;
 
-        if (res->write_res.verifier.committed != NFS_FILE_SYNC) {
-                status = nfs_commit_file(dst, &res->write_res.verifier.verifier);
-                if (status)
-                        return status;
+        if (!nfs_write_verifier_cmp(&res->write_res.verifier.verifier,
+                                    &res->commit_res.verf->verifier)) {
+                status = -EAGAIN;
+                goto out;
         }
 
         truncate_pagecache_range(dst_inode, pos_dst,
                                  pos_dst + res->write_res.count);
 
-        return res->write_res.count;
+        status = res->write_res.count;
+out:
+        kfree(res->commit_res.verf);
+        return status;
 }
 
 ssize_t nfs42_proc_copy(struct file *src, loff_t pos_src,
@@ -240,6 +246,9 @@ ssize_t nfs42_proc_copy(struct file *src, loff_t pos_src,
                 if (err == -ENOTSUPP) {
                         err = -EOPNOTSUPP;
                         break;
+                } if (err == -EAGAIN) {
+                        dst_exception.retry = 1;
+                        continue;
                 }
 
                 err2 = nfs4_handle_exception(server, err, &src_exception);
diff --git a/fs/nfs/nfs42xdr.c b/fs/nfs/nfs42xdr.c
index 6c7296454bbc..528362f69cc1 100644
--- a/fs/nfs/nfs42xdr.c
+++ b/fs/nfs/nfs42xdr.c
@@ -66,12 +66,14 @@
                                          encode_putfh_maxsz + \
                                          encode_savefh_maxsz + \
                                          encode_putfh_maxsz + \
-                                         encode_copy_maxsz)
+                                         encode_copy_maxsz + \
+                                         encode_commit_maxsz)
 #define NFS4_dec_copy_sz                (compound_decode_hdr_maxsz + \
                                          decode_putfh_maxsz + \
                                          decode_savefh_maxsz + \
                                          decode_putfh_maxsz + \
-                                         decode_copy_maxsz)
+                                         decode_copy_maxsz + \
+                                         decode_commit_maxsz)
 #define NFS4_enc_deallocate_sz          (compound_encode_hdr_maxsz + \
                                          encode_putfh_maxsz + \
                                          encode_deallocate_maxsz + \
@@ -222,6 +224,18 @@ static void nfs4_xdr_enc_allocate(struct rpc_rqst *req,
         encode_nops(&hdr);
 }
 
+static void encode_copy_commit(struct xdr_stream *xdr,
+                          struct nfs42_copy_args *args,
+                          struct compound_hdr *hdr)
+{
+        __be32 *p;
+
+        encode_op_hdr(xdr, OP_COMMIT, decode_commit_maxsz, hdr);
+        p = reserve_space(xdr, 12);
+        p = xdr_encode_hyper(p, args->dst_pos);
+        *p = cpu_to_be32(args->count);
+}
+
 /*
  * Encode COPY request
  */
@@ -239,6 +253,7 @@ static void nfs4_xdr_enc_copy(struct rpc_rqst *req,
         encode_savefh(xdr, &hdr);
         encode_putfh(xdr, args->dst_fh, &hdr);
         encode_copy(xdr, args, &hdr);
+        encode_copy_commit(xdr, args, &hdr);
         encode_nops(&hdr);
 }
 
@@ -481,6 +496,9 @@ static int nfs4_xdr_dec_copy(struct rpc_rqst *rqstp,
         if (status)
                 goto out;
         status = decode_copy(xdr, res);
+        if (status)
+                goto out;
+        status = decode_commit(xdr, &res->commit_res);
 out:
         return status;
 }
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 59e21cc0a266..85bfa416fcc8 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -1742,36 +1742,6 @@ nfs_commit_list(struct inode *inode, struct list_head *head, int how,
                                    data->mds_ops, how, 0);
 }
 
-int nfs_commit_file(struct file *file, struct nfs_write_verifier *verf)
-{
-        struct inode *inode = file_inode(file);
-        struct nfs_open_context *open;
-        struct nfs_commit_info cinfo;
-        struct nfs_page *req;
-        int ret;
-
-        open = get_nfs_open_context(nfs_file_open_context(file));
-        req  = nfs_create_request(open, NULL, NULL, 0, i_size_read(inode));
-        if (IS_ERR(req)) {
-                ret = PTR_ERR(req);
-                goto out_put;
-        }
-
-        nfs_init_cinfo_from_inode(&cinfo, inode);
-
-        memcpy(&req->wb_verf, verf, sizeof(struct nfs_write_verifier));
-        nfs_request_add_commit_list(req, &cinfo);
-        ret = nfs_commit_inode(inode, FLUSH_SYNC);
-        if (ret > 0)
-                ret = 0;
-
-        nfs_free_request(req);
-out_put:
-        put_nfs_open_context(open);
-        return ret;
-}
-EXPORT_SYMBOL_GPL(nfs_commit_file);
-
 /*
  * COMMIT call returned
  */
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 677c6b91dfcd..b28c83475ee8 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -1383,6 +1383,7 @@ struct nfs42_copy_res {
         struct nfs42_write_res          write_res;
         bool                            consecutive;
         bool                            synchronous;
+        struct nfs_commitres            commit_res;
 };
 
 struct nfs42_seek_args {