Merge tag 'nfs-for-4.4-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client updates from Trond Myklebust:
 "Highlights include:

  New features:
   - RDMA client backchannel from Chuck
   - Support for NFSv4.2 file CLONE using the btrfs ioctl

  Bugfixes + cleanups:
   - Move socket data receive out of the bottom halves and into a
     workqueue
   - Refactor NFSv4 error handling so synchronous and asynchronous RPC
     handles errors identically.
   - Fix a panic when blocks or object layouts reads return a bad data
     length
   - Fix nfsroot so it can handle a 1024 byte long path.
   - Fix bad usage of page offset in bl_read_pagelist
   - Various NFSv4 callback cleanups+fixes
   - Fix GETATTR bitmap verification
   - Support hexadecimal number for sunrpc debug sysctl files"

* tag 'nfs-for-4.4-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (53 commits)
  Sunrpc: Supports hexadecimal number for sysctl files of sunrpc debug
  nfs: Fix GETATTR bitmap verification
  nfs: Remove unused xdr page offsets in getacl/setacl arguments
  fs/nfs: remove unnecessary new_valid_dev check
  SUNRPC: fix variable type
  NFS: Enable client side NFSv4.1 backchannel to use other transports
  pNFS/flexfiles: Add support for FF_FLAGS_NO_IO_THRU_MDS
  pNFS/flexfiles: When mirrored, retry failed reads by switching mirrors
  SUNRPC: Remove the TCP-only restriction in bc_svc_process()
  svcrdma: Add backward direction service for RPC/RDMA transport
  xprtrdma: Handle incoming backward direction RPC calls
  xprtrdma: Add support for sending backward direction RPC replies
  xprtrdma: Pre-allocate Work Requests for backchannel
  xprtrdma: Pre-allocate backward rpc_rqst and send/receive buffers
  SUNRPC: Abstract backchannel operations
  xprtrdma: Saving IRQs no longer needed for rb_lock
  xprtrdma: Remove reply tasklet
  xprtrdma: Use workqueue to process RPC/RDMA replies
  xprtrdma: Replace send and receive arrays
  xprtrdma: Refactor reply handler error handling
  ...

1 files changed, 71 insertions, 0 deletions

diff --git a/fs/nfs/nfs42proc.c b/fs/nfs/nfs42proc.c
index 0f020e4d8421..3e92a3cde15d 100644
--- a/fs/nfs/nfs42proc.c
+++ b/fs/nfs/nfs42proc.c
@@ -271,3 +271,74 @@ int nfs42_proc_layoutstats_generic(struct nfs_server *server,
                 return PTR_ERR(task);
         return 0;
 }
+
+static int _nfs42_proc_clone(struct rpc_message *msg, struct file *src_f,
+                             struct file *dst_f, loff_t src_offset,
+                             loff_t dst_offset, loff_t count)
+{
+        struct inode *src_inode = file_inode(src_f);
+        struct inode *dst_inode = file_inode(dst_f);
+        struct nfs_server *server = NFS_SERVER(dst_inode);
+        struct nfs42_clone_args args = {
+                .src_fh = NFS_FH(src_inode),
+                .dst_fh = NFS_FH(dst_inode),
+                .src_offset = src_offset,
+                .dst_offset = dst_offset,
+                .dst_bitmask = server->cache_consistency_bitmask,
+        };
+        struct nfs42_clone_res res = {
+                .server = server,
+        };
+        int status;
+
+        msg->rpc_argp = &args;
+        msg->rpc_resp = &res;
+
+        status = nfs42_set_rw_stateid(&args.src_stateid, src_f, FMODE_READ);
+        if (status)
+                return status;
+
+        status = nfs42_set_rw_stateid(&args.dst_stateid, dst_f, FMODE_WRITE);
+        if (status)
+                return status;
+
+        res.dst_fattr = nfs_alloc_fattr();
+        if (!res.dst_fattr)
+                return -ENOMEM;
+
+        status = nfs4_call_sync(server->client, server, msg,
+                                &args.seq_args, &res.seq_res, 0);
+        if (status == 0)
+                status = nfs_post_op_update_inode(dst_inode, res.dst_fattr);
+
+        kfree(res.dst_fattr);
+        return status;
+}
+
+int nfs42_proc_clone(struct file *src_f, struct file *dst_f,
+                     loff_t src_offset, loff_t dst_offset, loff_t count)
+{
+        struct rpc_message msg = {
+                .rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_CLONE],
+        };
+        struct inode *inode = file_inode(src_f);
+        struct nfs_server *server = NFS_SERVER(file_inode(src_f));
+        struct nfs4_exception exception = { };
+        int err;
+
+        if (!nfs_server_capable(inode, NFS_CAP_CLONE))
+                return -EOPNOTSUPP;
+
+        do {
+                err = _nfs42_proc_clone(&msg, src_f, dst_f, src_offset,
+                                        dst_offset, count);
+                if (err == -ENOTSUPP || err == -EOPNOTSUPP) {
+                        NFS_SERVER(inode)->caps &= ~NFS_CAP_CLONE;
+                        return -EOPNOTSUPP;
+                }
+                err = nfs4_handle_exception(server, err, &exception);
+        } while (exception.retry);
+
+        return err;
+
+}