IB/core: Make ib_dealloc_pd return void
The majority of callers never check the return value, and even if they
did, they can't do anything about a failure.
All possible failure cases represent a bug in the caller, so just
WARN_ON inside the function instead.
This fixes a few random errors:
net/rd/iw.c infinite loops while it fails. (racing with EBUSY?)
This also lays the ground work to get rid of error return from the
drivers. Most drivers do not error, the few that do are broken since
it cannot be handled.
Since uverbs can legitimately make use of EBUSY, open code the
check.
Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c
index 258485e..4c98696 100644
--- a/drivers/infiniband/core/uverbs_cmd.c
+++ b/drivers/infiniband/core/uverbs_cmd.c
@@ -606,6 +606,7 @@
{
struct ib_uverbs_dealloc_pd cmd;
struct ib_uobject *uobj;
+ struct ib_pd *pd;
int ret;
if (copy_from_user(&cmd, buf, sizeof cmd))
@@ -614,15 +615,20 @@
uobj = idr_write_uobj(&ib_uverbs_pd_idr, cmd.pd_handle, file->ucontext);
if (!uobj)
return -EINVAL;
+ pd = uobj->object;
- ret = ib_dealloc_pd(uobj->object);
- if (!ret)
- uobj->live = 0;
+ if (atomic_read(&pd->usecnt)) {
+ ret = -EBUSY;
+ goto err_put;
+ }
- put_uobj_write(uobj);
-
+ ret = pd->device->dealloc_pd(uobj->object);
+ WARN_ONCE(ret, "Infiniband HW driver failed dealloc_pd");
if (ret)
- return ret;
+ goto err_put;
+
+ uobj->live = 0;
+ put_uobj_write(uobj);
idr_remove_uobj(&ib_uverbs_pd_idr, uobj);
@@ -633,6 +639,10 @@
put_uobj(uobj);
return in_len;
+
+err_put:
+ put_uobj_write(uobj);
+ return ret;
}
struct xrcd_table_entry {
diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c
index 2e5fd89..aad8b3c 100644
--- a/drivers/infiniband/core/verbs.c
+++ b/drivers/infiniband/core/verbs.c
@@ -260,18 +260,32 @@
}
EXPORT_SYMBOL(ib_alloc_pd);
-int ib_dealloc_pd(struct ib_pd *pd)
+/**
+ * ib_dealloc_pd - Deallocates a protection domain.
+ * @pd: The protection domain to deallocate.
+ *
+ * It is an error to call this function while any resources in the pd still
+ * exist. The caller is responsible to synchronously destroy them and
+ * guarantee no new allocations will happen.
+ */
+void ib_dealloc_pd(struct ib_pd *pd)
{
+ int ret;
+
if (pd->local_mr) {
- if (ib_dereg_mr(pd->local_mr))
- return -EBUSY;
+ ret = ib_dereg_mr(pd->local_mr);
+ WARN_ON(ret);
pd->local_mr = NULL;
}
- if (atomic_read(&pd->usecnt))
- return -EBUSY;
+ /* uverbs manipulates usecnt with proper locking, while the kabi
+ requires the caller to guarantee we can't race here. */
+ WARN_ON(atomic_read(&pd->usecnt));
- return pd->device->dealloc_pd(pd);
+ /* Making delalloc_pd a void return is a WIP, no driver should return
+ an error here. */
+ ret = pd->device->dealloc_pd(pd);
+ WARN_ONCE(ret, "Infiniband HW driver failed dealloc_pd");
}
EXPORT_SYMBOL(ib_dealloc_pd);
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_verbs.c b/drivers/infiniband/ulp/ipoib/ipoib_verbs.c
index 8c45198..78845b6 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_verbs.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_verbs.c
@@ -280,9 +280,7 @@
priv->wq = NULL;
}
- if (ib_dealloc_pd(priv->pd))
- ipoib_warn(priv, "ib_dealloc_pd failed\n");
-
+ ib_dealloc_pd(priv->pd);
}
void ipoib_event(struct ib_event_handler *handler,
diff --git a/drivers/infiniband/ulp/iser/iser_verbs.c b/drivers/infiniband/ulp/iser/iser_verbs.c
index ad2d2b5..ae70cc1 100644
--- a/drivers/infiniband/ulp/iser/iser_verbs.c
+++ b/drivers/infiniband/ulp/iser/iser_verbs.c
@@ -185,7 +185,7 @@
(void)ib_unregister_event_handler(&device->event_handler);
(void)ib_dereg_mr(device->mr);
- (void)ib_dealloc_pd(device->pd);
+ ib_dealloc_pd(device->pd);
kfree(device->comps);
device->comps = NULL;
diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index 0940051..128abf2 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -2196,11 +2196,7 @@
struct ib_pd *ib_alloc_pd(struct ib_device *device);
-/**
- * ib_dealloc_pd - Deallocates a protection domain.
- * @pd: The protection domain to deallocate.
- */
-int ib_dealloc_pd(struct ib_pd *pd);
+void ib_dealloc_pd(struct ib_pd *pd);
/**
* ib_create_ah - Creates an address handle for the given address vector.
diff --git a/net/rds/iw.c b/net/rds/iw.c
index 7cc2f32..c7dcddb 100644
--- a/net/rds/iw.c
+++ b/net/rds/iw.c
@@ -148,10 +148,7 @@
if (rds_iwdev->mr)
ib_dereg_mr(rds_iwdev->mr);
- while (ib_dealloc_pd(rds_iwdev->pd)) {
- rdsdebug("Failed to dealloc pd %p\n", rds_iwdev->pd);
- msleep(1);
- }
+ ib_dealloc_pd(rds_iwdev->pd);
list_del(&rds_iwdev->list);
kfree(rds_iwdev);
diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c
index 891c4ed..afd5043 100644
--- a/net/sunrpc/xprtrdma/verbs.c
+++ b/net/sunrpc/xprtrdma/verbs.c
@@ -624,7 +624,7 @@
/* If the pd is still busy, xprtrdma missed freeing a resource */
if (ia->ri_pd && !IS_ERR(ia->ri_pd))
- WARN_ON(ib_dealloc_pd(ia->ri_pd));
+ ib_dealloc_pd(ia->ri_pd);
}
/*