]> err.no Git - linux-2.6/blobdiff - net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
[linux-2.6] / net / sunrpc / xprtrdma / svc_rdma_recvfrom.c
index 971271602dd07e5ae97b0e42b42f02cc2b9f4eb9..06ab4841537b236a395377098fb073ca3060a549 100644 (file)
@@ -260,11 +260,16 @@ static int rdma_read_max_sge(struct svcxprt_rdma *xprt, int sge_count)
  * On our side, we need to read into a pagelist. The first page immediately
  * follows the RPC header.
  *
- * This function returns 1 to indicate success. The data is not yet in
+ * This function returns:
+ * 0 - No error and no read-list found.
+ *
+ * 1 - Successful read-list processing. The data is not yet in
  * the pagelist and therefore the RPC request must be deferred. The
  * I/O completion will enqueue the transport again and
  * svc_rdma_recvfrom will complete the request.
  *
+ * <0 - Error processing/posting read-list.
+ *
  * NOTE: The ctxt must not be touched after the last WR has been posted
  * because the I/O completion processing may occur on another
  * processor and free / modify the context. Ne touche pas!
@@ -284,7 +289,6 @@ static int rdma_read_xdr(struct svcxprt_rdma *xprt,
        u64 sgl_offset;
        struct rpcrdma_read_chunk *ch;
        struct svc_rdma_op_ctxt *ctxt = NULL;
-       struct svc_rdma_op_ctxt *head;
        struct svc_rdma_op_ctxt *tmp_sge_ctxt;
        struct svc_rdma_op_ctxt *tmp_ch_ctxt;
        struct chunk_sge *ch_sge_ary;
@@ -302,35 +306,20 @@ static int rdma_read_xdr(struct svcxprt_rdma *xprt,
        ch_sge_ary = (struct chunk_sge *)tmp_ch_ctxt->sge;
 
        svc_rdma_rcl_chunk_counts(ch, &ch_count, &byte_count);
+       if (ch_count > RPCSVC_MAXPAGES)
+               return -EINVAL;
        sge_count = rdma_rcl_to_sge(xprt, rqstp, hdr_ctxt, rmsgp,
                                    sge, ch_sge_ary,
                                    ch_count, byte_count);
-       head = svc_rdma_get_context(xprt);
        sgl_offset = 0;
        ch_no = 0;
 
        for (ch = (struct rpcrdma_read_chunk *)&rmsgp->rm_body.rm_chunks[0];
             ch->rc_discrim != 0; ch++, ch_no++) {
 next_sge:
-               if (!ctxt)
-                       ctxt = head;
-               else {
-                       ctxt->next = svc_rdma_get_context(xprt);
-                       ctxt = ctxt->next;
-               }
-               ctxt->next = NULL;
+               ctxt = svc_rdma_get_context(xprt);
                ctxt->direction = DMA_FROM_DEVICE;
-               clear_bit(RDMACTXT_F_READ_DONE, &ctxt->flags);
                clear_bit(RDMACTXT_F_LAST_CTXT, &ctxt->flags);
-               if ((ch+1)->rc_discrim == 0) {
-                       /*
-                        * Checked in sq_cq_reap to see if we need to
-                        * be enqueued
-                        */
-                       set_bit(RDMACTXT_F_LAST_CTXT, &ctxt->flags);
-                       ctxt->next = hdr_ctxt;
-                       hdr_ctxt->next = head;
-               }
 
                /* Prepare READ WR */
                memset(&read_wr, 0, sizeof read_wr);
@@ -348,18 +337,23 @@ next_sge:
                rdma_set_ctxt_sge(ctxt, &sge[ch_sge_ary[ch_no].start],
                                  &sgl_offset,
                                  read_wr.num_sge);
-
+               if (((ch+1)->rc_discrim == 0) &&
+                   (read_wr.num_sge == ch_sge_ary[ch_no].count)) {
+                       /*
+                        * Mark the last RDMA_READ with a bit to
+                        * indicate all RPC data has been fetched from
+                        * the client and the RPC needs to be enqueued.
+                        */
+                       set_bit(RDMACTXT_F_LAST_CTXT, &ctxt->flags);
+                       ctxt->read_hdr = hdr_ctxt;
+               }
                /* Post the read */
                err = svc_rdma_send(xprt, &read_wr);
                if (err) {
-                       printk(KERN_ERR "svcrdma: Error posting send = %d\n",
+                       printk(KERN_ERR "svcrdma: Error %d posting RDMA_READ\n",
                               err);
-                       /*
-                        * Break the circular list so free knows when
-                        * to stop if the error happened to occur on
-                        * the last read
-                        */
-                       ctxt->next = NULL;
+                       set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags);
+                       svc_rdma_put_context(ctxt, 0);
                        goto out;
                }
                atomic_inc(&rdma_stat_read);
@@ -370,7 +364,7 @@ next_sge:
                        goto next_sge;
                }
                sgl_offset = 0;
-               err = 0;
+               err = 1;
        }
 
  out:
@@ -388,25 +382,12 @@ next_sge:
        while (rqstp->rq_resused)
                rqstp->rq_respages[--rqstp->rq_resused] = NULL;
 
-       if (err) {
-               printk(KERN_ERR "svcrdma : RDMA_READ error = %d\n", err);
-               set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags);
-               /* Free the linked list of read contexts */
-               while (head != NULL) {
-                       ctxt = head->next;
-                       svc_rdma_put_context(head, 1);
-                       head = ctxt;
-               }
-               return 0;
-       }
-
-       return 1;
+       return err;
 }
 
 static int rdma_read_complete(struct svc_rqst *rqstp,
-                             struct svc_rdma_op_ctxt *data)
+                             struct svc_rdma_op_ctxt *head)
 {
-       struct svc_rdma_op_ctxt *head = data->next;
        int page_no;
        int ret;
 
@@ -432,21 +413,12 @@ static int rdma_read_complete(struct svc_rqst *rqstp,
        rqstp->rq_arg.len = head->arg.len;
        rqstp->rq_arg.buflen = head->arg.buflen;
 
+       /* Free the context */
+       svc_rdma_put_context(head, 0);
+
        /* XXX: What should this be? */
        rqstp->rq_prot = IPPROTO_MAX;
-
-       /*
-        * Free the contexts we used to build the RDMA_READ. We have
-        * to be careful here because the context list uses the same
-        * next pointer used to chain the contexts associated with the
-        * RDMA_READ
-        */
-       data->next = NULL;      /* terminate circular list */
-       do {
-               data = head->next;
-               svc_rdma_put_context(head, 0);
-               head = data;
-       } while (head != NULL);
+       svc_xprt_copy_addrs(rqstp, rqstp->rq_xprt);
 
        ret = rqstp->rq_arg.head[0].iov_len
                + rqstp->rq_arg.page_len
@@ -456,8 +428,6 @@ static int rdma_read_complete(struct svc_rqst *rqstp,
                ret, rqstp->rq_arg.len, rqstp->rq_arg.head[0].iov_base,
                rqstp->rq_arg.head[0].iov_len);
 
-       /* Indicate that we've consumed an RQ credit */
-       rqstp->rq_xprt_ctxt = rqstp->rq_xprt;
        svc_xprt_received(rqstp->rq_xprt);
        return ret;
 }
@@ -479,13 +449,6 @@ int svc_rdma_recvfrom(struct svc_rqst *rqstp)
 
        dprintk("svcrdma: rqstp=%p\n", rqstp);
 
-       /*
-        * The rq_xprt_ctxt indicates if we've consumed an RQ credit
-        * or not. It is used in the rdma xpo_release_rqst function to
-        * determine whether or not to return an RQ WQE to the RQ.
-        */
-       rqstp->rq_xprt_ctxt = NULL;
-
        spin_lock_bh(&rdma_xprt->sc_read_complete_lock);
        if (!list_empty(&rdma_xprt->sc_read_complete_q)) {
                ctxt = list_entry(rdma_xprt->sc_read_complete_q.next,
@@ -536,21 +499,22 @@ int svc_rdma_recvfrom(struct svc_rqst *rqstp)
        /* If the request is invalid, reply with an error */
        if (len < 0) {
                if (len == -ENOSYS)
-                       (void)svc_rdma_send_error(rdma_xprt, rmsgp, ERR_VERS);
+                       svc_rdma_send_error(rdma_xprt, rmsgp, ERR_VERS);
                goto close_out;
        }
 
-       /* Read read-list data. If we would need to wait, defer
-        * it. Not that in this case, we don't return the RQ credit
-        * until after the read completes.
-        */
-       if (rdma_read_xdr(rdma_xprt, rmsgp, rqstp, ctxt)) {
+       /* Read read-list data. */
+       ret = rdma_read_xdr(rdma_xprt, rmsgp, rqstp, ctxt);
+       if (ret > 0) {
+               /* read-list posted, defer until data received from client. */
                svc_xprt_received(xprt);
                return 0;
        }
-
-       /* Indicate we've consumed an RQ credit */
-       rqstp->rq_xprt_ctxt = rqstp->rq_xprt;
+       if (ret < 0) {
+               /* Post of read-list failed, free context. */
+               svc_rdma_put_context(ctxt, 1);
+               return 0;
+       }
 
        ret = rqstp->rq_arg.head[0].iov_len
                + rqstp->rq_arg.page_len
@@ -568,11 +532,8 @@ int svc_rdma_recvfrom(struct svc_rqst *rqstp)
        return ret;
 
  close_out:
-       if (ctxt) {
+       if (ctxt)
                svc_rdma_put_context(ctxt, 1);
-               /* Indicate we've consumed an RQ credit */
-               rqstp->rq_xprt_ctxt = rqstp->rq_xprt;
-       }
        dprintk("svcrdma: transport %p is closing\n", xprt);
        /*
         * Set the close bit and enqueue it. svc_recv will see the