ib_client API provides a way to wrap an ib_device with a specific ULP
structure. Using that API local lists and mutexes can be completely
avoided and allocation/removal paths become a bit cleaner.
Signed-off-by: Roman Pen <roman.penyaev@xxxxxxxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Steve Wise <swise@xxxxxxxxxxxxxxxxxxxxx>
Cc: Bart Van Assche <bart.vanassche@xxxxxxxxxxx>
Cc: Sagi Grimberg <sagi@xxxxxxxxxxx>
Cc: Doug Ledford <dledford@xxxxxxxxxx>
---
drivers/infiniband/ulp/iser/iscsi_iser.c | 21 +++++++---
drivers/infiniband/ulp/iser/iscsi_iser.h | 10 ++---
drivers/infiniband/ulp/iser/iser_verbs.c | 69 ++++++++++++++++++++------------
3 files changed, 64 insertions(+), 36 deletions(-)
diff --git a/drivers/infiniband/ulp/iser/iscsi_iser.c b/drivers/infiniband/ulp/iser/iscsi_iser.c
index 0336643c2ed6..bdfe4ab68bc6 100644
--- a/drivers/infiniband/ulp/iser/iscsi_iser.c
+++ b/drivers/infiniband/ulp/iser/iscsi_iser.c
@@ -83,7 +83,14 @@ static struct iscsi_transport iscsi_iser_transport;
static struct scsi_transport_template *iscsi_iser_scsi_transport;
static struct workqueue_struct *release_wq;
static DEFINE_MUTEX(unbind_iser_conn_mutex);
-struct iser_global ig;
+
+struct iser_global ig = {
+ .rdma_ib_client = {
+ .name = "iser_ib_client",
+ .add = iser_ib_client_add_one,
+ .remove = iser_ib_client_remove_one
+ }
+};
int iser_debug_level = 0;
module_param_named(debug_level, iser_debug_level, int, S_IRUGO | S_IWUSR);
@@ -1064,8 +1071,6 @@ static int __init iser_init(void)
return -EINVAL;
}
- memset(&ig, 0, sizeof(struct iser_global));
-
ig.desc_cache = kmem_cache_create("iser_descriptors",
sizeof(struct iser_tx_desc),
0, SLAB_HWCACHE_ALIGN,
@@ -1074,11 +1079,14 @@ static int __init iser_init(void)
return -ENOMEM;
/* device init is called only after the first addr resolution */
- mutex_init(&ig.device_list_mutex);
- INIT_LIST_HEAD(&ig.device_list);
mutex_init(&ig.connlist_mutex);
INIT_LIST_HEAD(&ig.connlist);
+ err = ib_register_client(&ig.rdma_ib_client);
+ if (unlikely(err)) {
+ iser_err("ib_register_client(): %d\n", err);
+ goto err_register_client;
+ }
release_wq = alloc_workqueue("release workqueue", 0, 0);
if (!release_wq) {
iser_err("failed to allocate release workqueue\n");
@@ -1099,6 +1107,8 @@ static int __init iser_init(void)
err_reg:
destroy_workqueue(release_wq);
err_alloc_wq:
+ ib_unregister_client(&ig.rdma_ib_client);
+err_register_client:
kmem_cache_destroy(ig.desc_cache);
return err;
@@ -1127,6 +1137,7 @@ static void __exit iser_exit(void)
iscsi_unregister_transport(&iscsi_iser_transport);
kmem_cache_destroy(ig.desc_cache);
+ ib_unregister_client(&ig.rdma_ib_client);
}
module_init(iser_init);
diff --git a/drivers/infiniband/ulp/iser/iscsi_iser.h b/drivers/infiniband/ulp/iser/iscsi_iser.h
index 09664e12bd6b..310f5e540c3d 100644
--- a/drivers/infiniband/ulp/iser/iscsi_iser.h
+++ b/drivers/infiniband/ulp/iser/iscsi_iser.h
@@ -364,7 +364,6 @@ struct iser_reg_ops {
* @pd: Protection Domain for this device
* @mr: Global DMA memory region
* @event_handler: IB events handle routine
- * @ig_list: entry in devices list
* @refcount: Reference counter, dominated by open iser connections
* @comps_used: Number of completion contexts used, Min between online
* cpus and device max completion vectors
@@ -558,15 +557,13 @@ struct iser_page_vec {
/**
* struct iser_global: iSER global context
*
- * @device_list_mutex: protects device_list
- * @device_list: iser devices global list
+ * @rdma_ib_client: IB client
* @connlist_mutex: protects connlist
* @connlist: iser connections global list
* @desc_cache: kmem cache for tx dataout
*/
struct iser_global {
- struct mutex device_list_mutex;
- struct list_head device_list;
+ struct ib_client rdma_ib_client;
struct mutex connlist_mutex;
struct list_head connlist;
struct kmem_cache *desc_cache;
@@ -579,6 +576,9 @@ extern int iser_pi_guard;
extern unsigned int iser_max_sectors;
extern bool iser_always_reg;
+void iser_ib_client_add_one(struct ib_device *ib_device);
+void iser_ib_client_remove_one(struct ib_device *ib_device, void *client_data);
+
int iser_assign_reg_ops(struct iser_device *device);
int iser_send_control(struct iscsi_conn *conn,
diff --git a/drivers/infiniband/ulp/iser/iser_verbs.c b/drivers/infiniband/ulp/iser/iser_verbs.c
index 786f348e27c1..c67ceb87fb5e 100644
--- a/drivers/infiniband/ulp/iser/iser_verbs.c
+++ b/drivers/infiniband/ulp/iser/iser_verbs.c
@@ -491,55 +491,72 @@ static int iser_create_ib_conn_res(struct ib_conn *ib_conn)
return ret;
}
-/**
- * based on the resolved device node GUID see if there already allocated
- * device for this device. If there's no such, create one.
- */
static
struct iser_device *iser_device_find_by_ib_device(struct rdma_cm_id *cma_id)
{
struct iser_device *device;
- mutex_lock(&ig.device_list_mutex);
+ /* Paired with iser_ib_client_remove_one() */
+ rcu_read_lock();
+ device = ib_get_client_data(cma_id->device, &ig.rdma_ib_client);
+ if (device && WARN_ON(!refcount_inc_not_zero(&device->refcount)))
+ device = NULL;
+ rcu_read_unlock();
- list_for_each_entry(device, &ig.device_list, ig_list)
- /* find if there's a match using the node GUID */
- if (device->ib_device->node_guid == cma_id->device->node_guid)
- goto inc_refcnt;
+ return device;
+}
+
+static struct iser_device *iser_device_alloc(struct ib_device *ib_device)
+{
+ struct iser_device *device;
device = kzalloc(sizeof *device, GFP_KERNEL);
- if (device == NULL)
- goto out;
+ if (unlikely(!device))
+ return NULL;
- /* assign this device to the device */
- device->ib_device = cma_id->device;
- /* init the device and link it into ig device list */
+ refcount_set(&device->refcount, 1);
+ device->ib_device = ib_device;
if (iser_create_device_ib_res(device)) {
kfree(device);
- device = NULL;
- goto out;
+ return NULL;
}
- list_add(&device->ig_list, &ig.device_list);
-inc_refcnt:
- refcount_inc(&device->refcount);
-out:
- mutex_unlock(&ig.device_list_mutex);
return device;
}
/* if there's no demand for this device, release it */
static void iser_device_try_release(struct iser_device *device)
{
- mutex_lock(&ig.device_list_mutex);
iser_info("device %p refcount %d\n", device,
refcount_read(&device->refcount));
if (refcount_dec_and_test(&device->refcount)) {
iser_free_device_ib_res(device);
- list_del(&device->ig_list);
kfree(device);
}
- mutex_unlock(&ig.device_list_mutex);
+}
+
+void iser_ib_client_add_one(struct ib_device *ib_device)
+{
+ struct iser_device *device;
+
+ device = iser_device_alloc(ib_device);
+ if (likely(device))
+ ib_set_client_data(ib_device, &ig.rdma_ib_client, device);
+ else
+ pr_err("Allocattion of a device failed.\n");
+}
+
+void iser_ib_client_remove_one(struct ib_device *ib_device, void *client_data)
+{
+ struct iser_device *device = client_data;
+
+ if (unlikely(!device))
+ return;
+
+ ib_set_client_data(ib_device, &ig.rdma_ib_client, NULL);
+ /* Paired with iser_device_find_by_ib_device() */
+ synchronize_rcu();
+ iser_device_try_release(device);
}
/**
@@ -735,8 +752,8 @@ static void iser_addr_handler(struct rdma_cm_id *cma_id)
ib_conn = &iser_conn->ib_conn;
device = iser_device_find_by_ib_device(cma_id);
- if (!device) {
- iser_err("device lookup/creation failed\n");
+ if (unlikely(!device)) {
+ iser_err("no device exists\n");
iser_connect_error(cma_id);
return;
}
--
2.13.1
--
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