SUNRPC: Clean up allocation and freeing of back channel requests

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

diff --git a/net/sunrpc/backchannel_rqst.c b/net/sunrpc/backchannel_rqst.c
index 28504dfd3dad545aae381d912c36d89ab404bc2b..1baa41099469dad441d7c3edff1480138645ff4a 100644 (file)
--- a/net/sunrpc/backchannel_rqst.c
+++ b/net/sunrpc/backchannel_rqst.c
@@ -67,6 +67,55 @@ static void xprt_free_allocation(struct rpc_rqst *req)
        kfree(req);
 }
 
+static int xprt_alloc_xdr_buf(struct xdr_buf *buf, gfp_t gfp_flags)
+{
+       struct page *page;
+       /* Preallocate one XDR receive buffer */
+       page = alloc_page(gfp_flags);
+       if (page == NULL)
+               return -ENOMEM;
+       buf->head[0].iov_base = page_address(page);
+       buf->head[0].iov_len = PAGE_SIZE;
+       buf->tail[0].iov_base = NULL;
+       buf->tail[0].iov_len = 0;
+       buf->page_len = 0;
+       buf->len = 0;
+       buf->buflen = PAGE_SIZE;
+       return 0;
+}
+
+static
+struct rpc_rqst *xprt_alloc_bc_req(struct rpc_xprt *xprt, gfp_t gfp_flags)
+{
+       struct rpc_rqst *req;
+
+       /* Pre-allocate one backchannel rpc_rqst */
+       req = kzalloc(sizeof(*req), gfp_flags);
+       if (req == NULL)
+               return NULL;
+
+       req->rq_xprt = xprt;
+       INIT_LIST_HEAD(&req->rq_list);
+       INIT_LIST_HEAD(&req->rq_bc_list);
+
+       /* Preallocate one XDR receive buffer */
+       if (xprt_alloc_xdr_buf(&req->rq_rcv_buf, gfp_flags) < 0) {
+               printk(KERN_ERR "Failed to create bc receive xbuf\n");
+               goto out_free;
+       }
+       req->rq_rcv_buf.len = PAGE_SIZE;
+
+       /* Preallocate one XDR send buffer */
+       if (xprt_alloc_xdr_buf(&req->rq_snd_buf, gfp_flags) < 0) {
+               printk(KERN_ERR "Failed to create bc snd xbuf\n");
+               goto out_free;
+       }
+       return req;
+out_free:
+       xprt_free_allocation(req);
+       return NULL;
+}
+
 /*
  * Preallocate up to min_reqs structures and related buffers for use
  * by the backchannel.  This function can be called multiple times
@@ -87,9 +136,7 @@ static void xprt_free_allocation(struct rpc_rqst *req)
  */
 int xprt_setup_backchannel(struct rpc_xprt *xprt, unsigned int min_reqs)
 {
-       struct page *page_rcv = NULL, *page_snd = NULL;
-       struct xdr_buf *xbufp = NULL;
-       struct rpc_rqst *req, *tmp;
+       struct rpc_rqst *req;
        struct list_head tmp_list;
        int i;
 
@@ -106,7 +153,7 @@ int xprt_setup_backchannel(struct rpc_xprt *xprt, unsigned int min_reqs)
        INIT_LIST_HEAD(&tmp_list);
        for (i = 0; i < min_reqs; i++) {
                /* Pre-allocate one backchannel rpc_rqst */
-               req = kzalloc(sizeof(struct rpc_rqst), GFP_KERNEL);
+               req = xprt_alloc_bc_req(xprt, GFP_KERNEL);
                if (req == NULL) {
                        printk(KERN_ERR "Failed to create bc rpc_rqst\n");
                        goto out_free;
@@ -115,41 +162,6 @@ int xprt_setup_backchannel(struct rpc_xprt *xprt, unsigned int min_reqs)
                /* Add the allocated buffer to the tmp list */
                dprintk("RPC:       adding req= %p\n", req);
                list_add(&req->rq_bc_pa_list, &tmp_list);
-
-               req->rq_xprt = xprt;
-               INIT_LIST_HEAD(&req->rq_list);
-               INIT_LIST_HEAD(&req->rq_bc_list);
-
-               /* Preallocate one XDR receive buffer */
-               page_rcv = alloc_page(GFP_KERNEL);
-               if (page_rcv == NULL) {
-                       printk(KERN_ERR "Failed to create bc receive xbuf\n");
-                       goto out_free;
-               }
-               xbufp = &req->rq_rcv_buf;
-               xbufp->head[0].iov_base = page_address(page_rcv);
-               xbufp->head[0].iov_len = PAGE_SIZE;
-               xbufp->tail[0].iov_base = NULL;
-               xbufp->tail[0].iov_len = 0;
-               xbufp->page_len = 0;
-               xbufp->len = PAGE_SIZE;
-               xbufp->buflen = PAGE_SIZE;
-
-               /* Preallocate one XDR send buffer */
-               page_snd = alloc_page(GFP_KERNEL);
-               if (page_snd == NULL) {
-                       printk(KERN_ERR "Failed to create bc snd xbuf\n");
-                       goto out_free;
-               }
-
-               xbufp = &req->rq_snd_buf;
-               xbufp->head[0].iov_base = page_address(page_snd);
-               xbufp->head[0].iov_len = 0;
-               xbufp->tail[0].iov_base = NULL;
-               xbufp->tail[0].iov_len = 0;
-               xbufp->page_len = 0;
-               xbufp->len = 0;
-               xbufp->buflen = PAGE_SIZE;
        }
 
        /*
@@ -167,7 +179,10 @@ out_free:
        /*
         * Memory allocation failed, free the temporary list
         */
-       list_for_each_entry_safe(req, tmp, &tmp_list, rq_bc_pa_list) {
+       while (!list_empty(&tmp_list)) {
+               req = list_first_entry(&tmp_list,
+                               struct rpc_rqst,
+                               rq_bc_pa_list);
                list_del(&req->rq_bc_pa_list);
                xprt_free_allocation(req);
        }