NFS: Create a common rw_header_alloc and rw_header_free function

I create a new struct nfs_rw_ops to decide the differences between reads
and writes.  This struct will be set when initializing a new
nfs_pgio_descriptor, and then passed on to the nfs_rw_header when a new
header is allocated.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

1 files changed, 12 insertions, 16 deletions

diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 0dc4d6a28bd0..9c5cde38da45 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -46,6 +46,7 @@ static const struct rpc_call_ops nfs_write_common_ops;
 static const struct rpc_call_ops nfs_commit_ops;
 static const struct nfs_pgio_completion_ops nfs_async_write_completion_ops;
 static const struct nfs_commit_completion_ops nfs_commit_completion_ops;
+static const struct nfs_rw_ops nfs_rw_write_ops;
 
 static struct kmem_cache *nfs_wdata_cachep;
 static mempool_t *nfs_wdata_mempool;
@@ -70,29 +71,19 @@ void nfs_commit_free(struct nfs_commit_data *p)
 }
 EXPORT_SYMBOL_GPL(nfs_commit_free);
 
-struct nfs_rw_header *nfs_writehdr_alloc(void)
+static struct nfs_rw_header *nfs_writehdr_alloc(void)
 {
         struct nfs_rw_header *p = mempool_alloc(nfs_wdata_mempool, GFP_NOIO);
 
-        if (p) {
-                struct nfs_pgio_header *hdr = &p->header;
-
+        if (p)
                 memset(p, 0, sizeof(*p));
-                INIT_LIST_HEAD(&hdr->pages);
-                INIT_LIST_HEAD(&hdr->rpc_list);
-                spin_lock_init(&hdr->lock);
-                atomic_set(&hdr->refcnt, 0);
-        }
         return p;
 }
-EXPORT_SYMBOL_GPL(nfs_writehdr_alloc);
 
-void nfs_writehdr_free(struct nfs_pgio_header *hdr)
+static void nfs_writehdr_free(struct nfs_rw_header *whdr)
 {
-        struct nfs_rw_header *whdr = container_of(hdr, struct nfs_rw_header, header);
         mempool_free(whdr, nfs_wdata_mempool);
 }
-EXPORT_SYMBOL_GPL(nfs_writehdr_free);
 
 static void nfs_context_set_write_error(struct nfs_open_context *ctx, int error)
 {
@@ -1210,13 +1201,13 @@ static int nfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc)
         struct nfs_pgio_header *hdr;
         int ret;
 
-        whdr = nfs_writehdr_alloc();
+        whdr = nfs_rw_header_alloc(desc->pg_rw_ops);
         if (!whdr) {
                 desc->pg_completion_ops->error_cleanup(&desc->pg_list);
                 return -ENOMEM;
         }
         hdr = &whdr->header;
-        nfs_pgheader_init(desc, hdr, nfs_writehdr_free);
+        nfs_pgheader_init(desc, hdr, nfs_rw_header_free);
         atomic_inc(&hdr->refcnt);
         ret = nfs_generic_flush(desc, hdr);
         if (ret == 0)
@@ -1244,7 +1235,8 @@ void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio,
         if (server->pnfs_curr_ld && !force_mds)
                 pg_ops = server->pnfs_curr_ld->pg_write_ops;
 #endif
-        nfs_pageio_init(pgio, inode, pg_ops, compl_ops, server->wsize, ioflags);
+        nfs_pageio_init(pgio, inode, pg_ops, compl_ops, &nfs_rw_write_ops,
+                        server->wsize, ioflags);
 }
 EXPORT_SYMBOL_GPL(nfs_pageio_init_write);
 
@@ -1925,3 +1917,7 @@ void nfs_destroy_writepagecache(void)
         kmem_cache_destroy(nfs_wdata_cachep);
 }
 
+static const struct nfs_rw_ops nfs_rw_write_ops = {
+        .rw_alloc_header        = nfs_writehdr_alloc,
+        .rw_free_header         = nfs_writehdr_free,
+};