NFS: add COPY_NOTIFY operation

Try using the delegation stateid, then the open stateid.

Only NL4_NETATTR, No support for NL4_NAME and NL4_URL.
Allow only one source server address to be returned for now.

To distinguish between same server copy offload ("intra") and
a copy between different server ("inter"), do a check of server
owner identity and also make sure server is capable of doing
a copy offload.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>

1 files changed, 91 insertions, 0 deletions

diff --git a/fs/nfs/nfs42proc.c b/fs/nfs/nfs42proc.c
index 5196bfa7894d..6317dd89cf43 100644
--- a/fs/nfs/nfs42proc.c
+++ b/fs/nfs/nfs42proc.c
@@ -3,6 +3,7 @@
  * Copyright (c) 2014 Anna Schumaker <Anna.Schumaker@Netapp.com>
  */
 #include <linux/fs.h>
+#include <linux/sunrpc/addr.h>
 #include <linux/sunrpc/sched.h>
 #include <linux/nfs.h>
 #include <linux/nfs3.h>
@@ -15,10 +16,30 @@
 #include "pnfs.h"
 #include "nfs4session.h"
 #include "internal.h"
+#include "delegation.h"
 
 #define NFSDBG_FACILITY NFSDBG_PROC
 static int nfs42_do_offload_cancel_async(struct file *dst, nfs4_stateid *std);
 
+static void nfs42_set_netaddr(struct file *filep, struct nfs42_netaddr *naddr)
+{
+	struct nfs_client *clp = (NFS_SERVER(file_inode(filep)))->nfs_client;
+	unsigned short port = 2049;
+
+	rcu_read_lock();
+	naddr->netid_len = scnprintf(naddr->netid,
+					sizeof(naddr->netid), "%s",
+					rpc_peeraddr2str(clp->cl_rpcclient,
+					RPC_DISPLAY_NETID));
+	naddr->addr_len = scnprintf(naddr->addr,
+					sizeof(naddr->addr),
+					"%s.%u.%u",
+					rpc_peeraddr2str(clp->cl_rpcclient,
+					RPC_DISPLAY_ADDR),
+					port >> 8, port & 255);
+	rcu_read_unlock();
+}
+
 static int _nfs42_proc_fallocate(struct rpc_message *msg, struct file *filep,
 		struct nfs_lock_context *lock, loff_t offset, loff_t len)
 {
@@ -459,6 +480,76 @@ static int nfs42_do_offload_cancel_async(struct file *dst,
 	return status;
 }
 
+int _nfs42_proc_copy_notify(struct file *src, struct file *dst,
+			    struct nfs42_copy_notify_args *args,
+			    struct nfs42_copy_notify_res *res)
+{
+	struct nfs_server *src_server = NFS_SERVER(file_inode(src));
+	struct rpc_message msg = {
+		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_COPY_NOTIFY],
+		.rpc_argp = args,
+		.rpc_resp = res,
+	};
+	int status;
+	struct nfs_open_context *ctx;
+	struct nfs_lock_context *l_ctx;
+
+	ctx = get_nfs_open_context(nfs_file_open_context(src));
+	l_ctx = nfs_get_lock_context(ctx);
+	if (IS_ERR(l_ctx))
+		return PTR_ERR(l_ctx);
+
+	status = nfs4_set_rw_stateid(&args->cna_src_stateid, ctx, l_ctx,
+				     FMODE_READ);
+	nfs_put_lock_context(l_ctx);
+	if (status)
+		return status;
+
+	status = nfs4_call_sync(src_server->client, src_server, &msg,
+				&args->cna_seq_args, &res->cnr_seq_res, 0);
+	if (status == -ENOTSUPP)
+		src_server->caps &= ~NFS_CAP_COPY_NOTIFY;
+
+	put_nfs_open_context(nfs_file_open_context(src));
+	return status;
+}
+
+int nfs42_proc_copy_notify(struct file *src, struct file *dst,
+				struct nfs42_copy_notify_res *res)
+{
+	struct nfs_server *src_server = NFS_SERVER(file_inode(src));
+	struct nfs42_copy_notify_args *args;
+	struct nfs4_exception exception = {
+		.inode = file_inode(src),
+	};
+	int status;
+
+	if (!(src_server->caps & NFS_CAP_COPY_NOTIFY))
+		return -EOPNOTSUPP;
+
+	args = kzalloc(sizeof(struct nfs42_copy_notify_args), GFP_NOFS);
+	if (args == NULL)
+		return -ENOMEM;
+
+	args->cna_src_fh  = NFS_FH(file_inode(src)),
+	args->cna_dst.nl4_type = NL4_NETADDR;
+	nfs42_set_netaddr(dst, &args->cna_dst.u.nl4_addr);
+	exception.stateid = &args->cna_src_stateid;
+
+	do {
+		status = _nfs42_proc_copy_notify(src, dst, args, res);
+		if (status == -ENOTSUPP) {
+			status = -EOPNOTSUPP;
+			goto out;
+		}
+		status = nfs4_handle_exception(src_server, status, &exception);
+	} while (exception.retry);
+
+out:
+	kfree(args);
+	return status;
+}
+
 static loff_t _nfs42_proc_llseek(struct file *filep,
 		struct nfs_lock_context *lock, loff_t offset, int whence)
 {