drbd: Use and idr data structure to map volume numbers to mdev pointers

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index ddd2ed7dec1cb44fd9204e60731ad8bd0e82bec9..8d32f9dc18edcb57f8a70cdcad03492eef6ac351 100644 (file)
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -40,6 +40,7 @@
 #include <linux/major.h>
 #include <linux/blkdev.h>
 #include <linux/genhd.h>
+#include <linux/idr.h>
 #include <net/tcp.h>
 #include <linux/lru_cache.h>
 #include <linux/prefetch.h>
@@ -916,8 +917,9 @@ struct drbd_tconn {                 /* is a resource from the config file */
        char *name;                     /* Resource name */
        struct list_head all_tconn;     /* List of all drbd_tconn, prot by global_state_lock */
        struct drbd_conf *volume0;      /* TODO: Remove me again */
-       unsigned long flags;
+       struct idr volumes;             /* <tconn, vnr> to mdev mapping */
 
+       unsigned long flags;
        struct net_conf *net_conf;      /* protected by get_net_conf() and put_net_conf() */
        atomic_t net_cnt;               /* Users of net_conf */
        wait_queue_head_t net_cnt_wait;

diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index 01749e9731dd448a09ce3e81c4088f517c114d6e..254e5c1413761ae6864151ba5f8d76122a7edd51 100644 (file)
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -2183,6 +2183,7 @@ struct drbd_tconn *drbd_new_tconn(char *name)
 
        atomic_set(&tconn->net_cnt, 0);
        init_waitqueue_head(&tconn->net_cnt_wait);
+       idr_init(&tconn->volumes);
 
        write_lock_irq(&global_state_lock);
        list_add(&tconn->all_tconn, &drbd_tconns);
@@ -2202,6 +2203,7 @@ void drbd_free_tconn(struct drbd_tconn *tconn)
        write_lock_irq(&global_state_lock);
        list_del(&tconn->all_tconn);
        write_unlock_irq(&global_state_lock);
+       idr_destroy(&tconn->volumes);
 
        kfree(tconn->name);
        kfree(tconn->int_dig_out);
@@ -2216,6 +2218,7 @@ struct drbd_conf *drbd_new_device(unsigned int minor)
        struct gendisk *disk;
        struct request_queue *q;
        char conn_name[9]; /* drbd1234N */
+       int vnr;
 
        /* GFP_KERNEL, we are outside of all write-out paths */
        mdev = kzalloc(sizeof(struct drbd_conf), GFP_KERNEL);
@@ -2225,7 +2228,14 @@ struct drbd_conf *drbd_new_device(unsigned int minor)
        mdev->tconn = drbd_new_tconn(conn_name);
        if (!mdev->tconn)
                goto out_no_tconn;
-
+       if (!idr_pre_get(&mdev->tconn->volumes, GFP_KERNEL))
+               goto out_no_cpumask;
+       if (idr_get_new(&mdev->tconn->volumes, mdev, &vnr))
+               goto out_no_cpumask;
+       if (vnr != 0) {
+               dev_err(DEV, "vnr = %d\n", vnr);
+               goto out_no_cpumask;
+       }
        if (!zalloc_cpumask_var(&mdev->cpu_mask, GFP_KERNEL))
                goto out_no_cpumask;