IB/core: Guarantee that a local_dma_lkey is available
Every single ULP requires a local_dma_lkey to do anything with
a QP, so let us ensure one exists for every PD created.
If the driver can supply a global local_dma_lkey then use that, otherwise
ask the driver to create a local use all physical memory MR associated
with the new PD.
Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Reviewed-by: Sagi Grimberg <sagig@dev.mellanox.co.il>
Acked-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Tested-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c
index c80ed17..2e5fd89 100644
--- a/drivers/infiniband/core/verbs.c
+++ b/drivers/infiniband/core/verbs.c
@@ -213,24 +213,61 @@
/* Protection domains */
+/**
+ * ib_alloc_pd - Allocates an unused protection domain.
+ * @device: The device on which to allocate the protection domain.
+ *
+ * A protection domain object provides an association between QPs, shared
+ * receive queues, address handles, memory regions, and memory windows.
+ *
+ * Every PD has a local_dma_lkey which can be used as the lkey value for local
+ * memory operations.
+ */
struct ib_pd *ib_alloc_pd(struct ib_device *device)
{
struct ib_pd *pd;
+ struct ib_device_attr devattr;
+ int rc;
+
+ rc = ib_query_device(device, &devattr);
+ if (rc)
+ return ERR_PTR(rc);
pd = device->alloc_pd(device, NULL, NULL);
+ if (IS_ERR(pd))
+ return pd;
- if (!IS_ERR(pd)) {
- pd->device = device;
- pd->uobject = NULL;
- atomic_set(&pd->usecnt, 0);
+ pd->device = device;
+ pd->uobject = NULL;
+ pd->local_mr = NULL;
+ atomic_set(&pd->usecnt, 0);
+
+ if (devattr.device_cap_flags & IB_DEVICE_LOCAL_DMA_LKEY)
+ pd->local_dma_lkey = device->local_dma_lkey;
+ else {
+ struct ib_mr *mr;
+
+ mr = ib_get_dma_mr(pd, IB_ACCESS_LOCAL_WRITE);
+ if (IS_ERR(mr)) {
+ ib_dealloc_pd(pd);
+ return (struct ib_pd *)mr;
+ }
+
+ pd->local_mr = mr;
+ pd->local_dma_lkey = pd->local_mr->lkey;
}
-
return pd;
}
EXPORT_SYMBOL(ib_alloc_pd);
int ib_dealloc_pd(struct ib_pd *pd)
{
+ if (pd->local_mr) {
+ if (ib_dereg_mr(pd->local_mr))
+ return -EBUSY;
+ pd->local_mr = NULL;
+ }
+
if (atomic_read(&pd->usecnt))
return -EBUSY;