drbd: Add struct drbd_resource->devices

This allows to access the volumes of a resource by number.

Signed-off-by: Andreas Gruenbacher <agruen@linbit.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>

diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index b66f908..73a7a6e 100644 (file)
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -539,6 +539,7 @@ enum {
 struct drbd_resource {
        char *name;
        struct kref kref;
+       struct idr devices;             /* volume number to device mapping */
        struct list_head connections;
        struct list_head resources;
 };
@@ -1202,6 +1203,7 @@ extern rwlock_t global_state_lock;
 extern int conn_lowest_minor(struct drbd_connection *connection);
 enum drbd_ret_code drbd_create_minor(struct drbd_connection *connection, unsigned int minor, int vnr);
 extern void drbd_destroy_device(struct kref *kref);
+extern void drbd_delete_minor(struct drbd_device *mdev);
 
 extern struct drbd_resource *drbd_create_resource(const char *name);
 extern void drbd_free_resource(struct drbd_resource *resource);

diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index 7d06d21..92479bd 100644 (file)
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -2162,7 +2162,8 @@ static void drbd_release_all_peer_reqs(struct drbd_device *device)
 void drbd_destroy_device(struct kref *kref)
 {
        struct drbd_device *device = container_of(kref, struct drbd_device, kref);
-       struct drbd_connection *connection = first_peer_device(device)->connection;
+       struct drbd_resource *resource = device->resource;
+       struct drbd_connection *connection;
 
        del_timer_sync(&device->request_timer);
 
@@ -2196,7 +2197,9 @@ void drbd_destroy_device(struct kref *kref)
        kfree(first_peer_device(device));
        kfree(device);
 
-       kref_put(&connection->kref, drbd_destroy_connection);
+       for_each_connection(connection, resource)
+               kref_put(&connection->kref, drbd_destroy_connection);
+       kref_put(&resource->kref, drbd_destroy_resource);
 }
 
 /* One global retry thread, if we need to push back some bio and have it
@@ -2282,6 +2285,7 @@ void drbd_destroy_resource(struct kref *kref)
        struct drbd_resource *resource =
                container_of(kref, struct drbd_resource, kref);
 
+       idr_destroy(&resource->devices);
        kfree(resource->name);
        kfree(resource);
 }
@@ -2321,14 +2325,8 @@ static void drbd_cleanup(void)
 
        drbd_genl_unregister();
 
-       idr_for_each_entry(&drbd_devices, device, i) {
-               idr_remove(&drbd_devices, device_to_minor(device));
-               idr_remove(&first_peer_device(device)->connection->volumes, device->vnr);
-               destroy_workqueue(device->submit.wq);
-               del_gendisk(device->vdisk);
-               /* synchronize_rcu(); No other threads running at this point */
-               kref_put(&device->kref, drbd_destroy_device);
-       }
+       idr_for_each_entry(&drbd_devices, device, i)
+               drbd_delete_minor(device);
 
        /* not _rcu since, no other updater anymore. Genl already unregistered */
        for_each_resource_safe(resource, tmp, &drbd_resources) {
@@ -2543,6 +2541,7 @@ struct drbd_resource *drbd_create_resource(const char *name)
                return NULL;
        }
        kref_init(&resource->kref);
+       idr_init(&resource->devices);
        INIT_LIST_HEAD(&resource->connections);
        list_add_tail_rcu(&resource->resources, &drbd_resources);
        return resource;
@@ -2658,6 +2657,7 @@ static int init_submitter(struct drbd_device *device)
 
 enum drbd_ret_code drbd_create_minor(struct drbd_connection *connection, unsigned int minor, int vnr)
 {
+       struct drbd_resource *resource = connection->resource;
        struct drbd_device *device;
        struct drbd_peer_device *peer_device;
        struct gendisk *disk;
@@ -2673,14 +2673,17 @@ enum drbd_ret_code drbd_create_minor(struct drbd_connection *connection, unsigne
        device = kzalloc(sizeof(struct drbd_device), GFP_KERNEL);
        if (!device)
                return ERR_NOMEM;
+       kref_init(&device->kref);
+
        peer_device = kzalloc(sizeof(struct drbd_peer_device), GFP_KERNEL);
        if (!peer_device)
                goto out_no_peer_device;
 
        INIT_LIST_HEAD(&device->peer_devices);
        list_add(&peer_device->peer_devices, &device->peer_devices);
+       kref_get(&resource->kref);
+       device->resource = resource;
        kref_get(&connection->kref);
-       device->resource = connection->resource;
        peer_device->connection = connection;
        peer_device->device = device;
 
@@ -2723,7 +2726,7 @@ enum drbd_ret_code drbd_create_minor(struct drbd_connection *connection, unsigne
        blk_queue_max_hw_sectors(q, DRBD_MAX_BIO_SIZE_SAFE >> 8);
        blk_queue_bounce_limit(q, BLK_BOUNCE_ANY);
        blk_queue_merge_bvec(q, drbd_merge_bvec);
-       q->queue_lock = &first_peer_device(device)->connection->req_lock; /* needed since we use */
+       q->queue_lock = &connection->req_lock;
 
        device->md_io_page = alloc_page(GFP_KERNEL);
        if (!device->md_io_page)
@@ -2742,6 +2745,17 @@ enum drbd_ret_code drbd_create_minor(struct drbd_connection *connection, unsigne
                }
                goto out_no_minor_idr;
        }
+       kref_get(&device->kref);
+
+       id = idr_alloc(&resource->devices, device, vnr, vnr + 1, GFP_KERNEL);
+       if (id < 0) {
+               if (id == -ENOSPC) {
+                       err = ERR_MINOR_EXISTS;
+                       drbd_msg_put_info("requested minor exists already");
+               }
+               goto out_idr_remove_minor;
+       }
+       kref_get(&device->kref);
 
        id = idr_alloc(&connection->volumes, device, vnr, vnr + 1, GFP_KERNEL);
        if (id < 0) {
@@ -2749,8 +2763,9 @@ enum drbd_ret_code drbd_create_minor(struct drbd_connection *connection, unsigne
                        err = ERR_INVALID_REQUEST;
                        drbd_msg_put_info("requested volume exists already");
                }
-               goto out_idr_remove_minor;
+               goto out_idr_remove_from_resource;
        }
+       kref_get(&device->kref);
 
        if (init_submitter(device)) {
                err = ERR_NOMEM;
@@ -2759,7 +2774,6 @@ enum drbd_ret_code drbd_create_minor(struct drbd_connection *connection, unsigne
        }
 
        add_disk(disk);
-       kref_init(&device->kref); /* one ref for both idrs and the the add_disk */
 
        /* inherit the connection state */
        device->state.conn = connection->cstate;
@@ -2770,6 +2784,8 @@ enum drbd_ret_code drbd_create_minor(struct drbd_connection *connection, unsigne
 
 out_idr_remove_vol:
        idr_remove(&connection->volumes, vnr);
+out_idr_remove_from_resource:
+       idr_remove(&resource->devices, vnr);
 out_idr_remove_minor:
        idr_remove(&drbd_devices, minor);
        synchronize_rcu();
@@ -2783,11 +2799,29 @@ out_no_disk:
        blk_cleanup_queue(q);
 out_no_q:
        kref_put(&connection->kref, drbd_destroy_connection);
+       kref_put(&resource->kref, drbd_destroy_resource);
 out_no_peer_device:
        kfree(device);
        return err;
 }
 
+void drbd_delete_minor(struct drbd_device *device)
+{
+       struct drbd_resource *resource = device->resource;
+       struct drbd_connection *connection;
+       int refs = 3;
+
+       for_each_connection(connection, resource) {
+               idr_remove(&connection->volumes, device->vnr);
+               refs++;
+       }
+       idr_remove(&resource->devices, device->vnr);
+       idr_remove(&drbd_devices, device_to_minor(device));
+       del_gendisk(device->vdisk);
+       synchronize_rcu();
+       kref_sub(&device->kref, refs, drbd_destroy_device);
+}
+
 int __init drbd_init(void)
 {
        int err;

diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index f563feb..bbd63e9 100644 (file)
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -3324,12 +3324,7 @@ static enum drbd_ret_code adm_del_minor(struct drbd_device *device)
            device->state.role == R_SECONDARY) {
                _drbd_request_state(device, NS(conn, C_WF_REPORT_PARAMS),
                                    CS_VERBOSE + CS_WAIT_COMPLETE);
-               idr_remove(&first_peer_device(device)->connection->volumes, device->vnr);
-               idr_remove(&drbd_devices, device_to_minor(device));
-               destroy_workqueue(device->submit.wq);
-               del_gendisk(device->vdisk);
-               synchronize_rcu();
-               kref_put(&device->kref, drbd_destroy_device);
+               drbd_delete_minor(device);
                return NO_ERROR;
        } else
                return ERR_MINOR_CONFIGURED;