NFS: create common nfs_pgio_header for both read and write

In order to avoid duplicating all the data in nfs_read_data whenever we
split it up into multiple RPC calls (either due to a short read result
or due to rsize < PAGE_SIZE), we split out the bits that are the same
per RPC call into a separate "header" structure.

The goal this patch moves towards is to have a single header
refcounted by several rpc_data structures.  Thus, want to always refer
from rpc_data to the header, and not the other way.  This patch comes
close to that ideal, but the directio code currently needs some
special casing, isolated in the nfs_direct_[read_write]hdr_release()
functions.  This will be dealt with in a future patch.

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 7 insertions, 3 deletions

diff --git a/fs/nfs/proc.c b/fs/nfs/proc.c
index bf80503200f5..22ee70586875 100644
--- a/fs/nfs/proc.c
+++ b/fs/nfs/proc.c
@@ -641,12 +641,14 @@ nfs_proc_pathconf(struct nfs_server *server, struct nfs_fh *fhandle,
 
 static int nfs_read_done(struct rpc_task *task, struct nfs_read_data *data)
 {
+        struct inode *inode = data->header->inode;
+
         if (nfs_async_handle_expired_key(task))
                 return -EAGAIN;
 
-        nfs_invalidate_atime(data->inode);
+        nfs_invalidate_atime(inode);
         if (task->tk_status >= 0) {
-                nfs_refresh_inode(data->inode, data->res.fattr);
+                nfs_refresh_inode(inode, data->res.fattr);
                 /* Emulate the eof flag, which isn't normally needed in NFSv2
                  * as it is guaranteed to always return the file attributes
                  */
@@ -668,11 +670,13 @@ static void nfs_proc_read_rpc_prepare(struct rpc_task *task, struct nfs_read_dat
 
 static int nfs_write_done(struct rpc_task *task, struct nfs_write_data *data)
 {
+        struct inode *inode = data->header->inode;
+
         if (nfs_async_handle_expired_key(task))
                 return -EAGAIN;
 
         if (task->tk_status >= 0)
-                nfs_post_op_update_inode_force_wcc(data->inode, data->res.fattr);
+                nfs_post_op_update_inode_force_wcc(inode, data->res.fattr);
         return 0;
 }