RDMA/cxgb4: Fail RDMA initialization for unsupported cards

The iw_cxgb4 module crashes at init time if the T4 card does not
support RDMA.  So clean up the init logic to correctly deal with
non-RDMA cards.

 - If any RDMA resources are not available, then fail the initialization
   logging an info message.
 - Clean up properly on initialization failures.

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

diff --git a/drivers/infiniband/hw/cxgb4/device.c b/drivers/infiniband/hw/cxgb4/device.c
index 40a13cc633a342befeeb452d713df087bb219149..6d0df6ec161b21f1a03347c12f5d7805ce5cbe70 100644 (file)
--- a/drivers/infiniband/hw/cxgb4/device.c
+++ b/drivers/infiniband/hw/cxgb4/device.c
@@ -376,10 +376,8 @@ struct uld_ctx {
        struct c4iw_dev *dev;
 };
 
-static void c4iw_remove(struct uld_ctx *ctx)
+static void c4iw_dealloc(struct uld_ctx *ctx)
 {
-       PDBG("%s c4iw_dev %p\n", __func__,  ctx->dev);
-       c4iw_unregister_device(ctx->dev);
        c4iw_rdev_close(&ctx->dev->rdev);
        idr_destroy(&ctx->dev->cqidr);
        idr_destroy(&ctx->dev->qpidr);
@@ -389,11 +387,30 @@ static void c4iw_remove(struct uld_ctx *ctx)
        ctx->dev = NULL;
 }
 
+static void c4iw_remove(struct uld_ctx *ctx)
+{
+       PDBG("%s c4iw_dev %p\n", __func__,  ctx->dev);
+       c4iw_unregister_device(ctx->dev);
+       c4iw_dealloc(ctx);
+}
+
+static int rdma_supported(const struct cxgb4_lld_info *infop)
+{
+       return infop->vr->stag.size > 0 && infop->vr->pbl.size > 0 &&
+              infop->vr->rq.size > 0 && infop->vr->qp.size > 0 &&
+              infop->vr->cq.size > 0 && infop->vr->ocq.size > 0;
+}
+
 static struct c4iw_dev *c4iw_alloc(const struct cxgb4_lld_info *infop)
 {
        struct c4iw_dev *devp;
        int ret;
 
+       if (!rdma_supported(infop)) {
+               printk(KERN_INFO MOD "%s: RDMA not supported on this device.\n",
+                      pci_name(infop->pdev));
+               return ERR_PTR(-ENOSYS);
+       }
        devp = (struct c4iw_dev *)ib_alloc_device(sizeof(*devp));
        if (!devp) {
                printk(KERN_ERR MOD "Cannot allocate ib device\n");
@@ -414,7 +431,6 @@ static struct c4iw_dev *c4iw_alloc(const struct cxgb4_lld_info *infop)
 
        ret = c4iw_rdev_open(&devp->rdev);
        if (ret) {
-               mutex_unlock(&dev_mutex);
                printk(KERN_ERR MOD "Unable to open CXIO rdev err %d\n", ret);
                ib_dealloc_device(&devp->ibdev);
                return ERR_PTR(ret);
@@ -519,15 +535,24 @@ static int c4iw_uld_state_change(void *handle, enum cxgb4_state new_state)
        case CXGB4_STATE_UP:
                printk(KERN_INFO MOD "%s: Up\n", pci_name(ctx->lldi.pdev));
                if (!ctx->dev) {
-                       int ret = 0;
+                       int ret;
 
                        ctx->dev = c4iw_alloc(&ctx->lldi);
-                       if (!IS_ERR(ctx->dev))
-                               ret = c4iw_register_device(ctx->dev);
-                       if (IS_ERR(ctx->dev) || ret)
+                       if (IS_ERR(ctx->dev)) {
+                               printk(KERN_ERR MOD
+                                      "%s: initialization failed: %ld\n",
+                                      pci_name(ctx->lldi.pdev),
+                                      PTR_ERR(ctx->dev));
+                               ctx->dev = NULL;
+                               break;
+                       }
+                       ret = c4iw_register_device(ctx->dev);
+                       if (ret) {
                                printk(KERN_ERR MOD
                                       "%s: RDMA registration failed: %d\n",
                                       pci_name(ctx->lldi.pdev), ret);
+                               c4iw_dealloc(ctx);
+                       }
                }
                break;
        case CXGB4_STATE_DOWN: