NBD: make nbd default to deadline I/O scheduler

[sfrench/cifs-2.6.git] / drivers / block / nbd.c

diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index ae3106045ee599d6072b6073fc674061a0d4c4e0..b53fdb0a282c4858590993bb790a003f3b436372 100644 (file)
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -54,7 +54,7 @@ static unsigned int debugflags;
 #endif /* NDEBUG */
 
 static unsigned int nbds_max = 16;
-static struct nbd_device nbd_dev[MAX_NBD];
+static struct nbd_device *nbd_dev;
 
 /*
  * Use just one lock (or at most 1 per NIC). Two arguments for this:
@@ -649,14 +649,13 @@ static int __init nbd_init(void)
 
        BUILD_BUG_ON(sizeof(struct nbd_request) != 28);
 
-       if (nbds_max > MAX_NBD) {
-               printk(KERN_CRIT "nbd: cannot allocate more than %u nbds; %u requested.\n", MAX_NBD,
-                               nbds_max);
-               return -EINVAL;
-       }
+       nbd_dev = kcalloc(nbds_max, sizeof(*nbd_dev), GFP_KERNEL);
+       if (!nbd_dev)
+               return -ENOMEM;
 
        for (i = 0; i < nbds_max; i++) {
                struct gendisk *disk = alloc_disk(1);
+               elevator_t *old_e;
                if (!disk)
                        goto out;
                nbd_dev[i].disk = disk;
@@ -670,6 +669,11 @@ static int __init nbd_init(void)
                        put_disk(disk);
                        goto out;
                }
+               old_e = disk->queue->elevator;
+               if (elevator_init(disk->queue, "deadline") == 0 ||
+                       elevator_init(disk->queue, "noop") == 0) {
+                               elevator_exit(old_e);
+               }
        }
 
        if (register_blkdev(NBD_MAJOR, "nbd")) {