bitkeeper revision 1.1108.49.1 (410e42bdH3VlmwH0Rslm9FIwkI7YLQ)

make access to block devices more robust

diff --git a/linux-2.6.7-xen-sparse/drivers/xen/blkback/vbd.c b/linux-2.6.7-xen-sparse/drivers/xen/blkback/vbd.c
index 540a8c1f3b95a87378a9f21f39bbdc9c94aa8af5..d05393cb0bcc7c6227f6a53f2c0d95624988d3eb 100644 (file)
--- a/linux-2.6.7-xen-sparse/drivers/xen/blkback/vbd.c
+++ b/linux-2.6.7-xen-sparse/drivers/xen/blkback/vbd.c
@@ -127,8 +127,17 @@ void vbd_grow(blkif_be_vbd_grow_t *grow)
     x->extent.device        = grow->extent.device;
     /* XXXcl see comments at top of open_by_devnum */
 #if 01
-    x->bdev = open_by_devnum(vbd_map_devnum(x->extent.device),
-                            vbd->readonly ? FMODE_READ : FMODE_WRITE);
+    x->bdev = bdget(vbd_map_devnum(x->extent.device));
+#ifndef DONT_BLKDEV_GET
+    if (x->bdev)
+       x->bdev = open_by_devnum(vbd_map_devnum(x->extent.device),
+                                vbd->readonly ? FMODE_READ : FMODE_WRITE);
+#endif
+    if (x->bdev == NULL) {
+       PRINTK("vbd_grow: device %08x doesn't exist.\n", x->extent.device);
+       grow->status = BLKIF_BE_STATUS_EXTENT_NOT_FOUND;
+       goto out;
+    }
 #endif
     /* XXXcl maybe bd_claim? */
     x->extent.sector_start  = grow->extent.sector_start;
@@ -231,6 +240,11 @@ void vbd_shrink(blkif_be_vbd_shrink_t *shrink)
 
     x   = *px;
     *px = x->next;
+
+#ifndef DONT_BLKDEV_GET
+    blkdev_put(x->bdev);
+#endif
+
     kfree(x);
 
     shrink->status = BLKIF_BE_STATUS_OKAY;
@@ -491,6 +505,15 @@ int vbd_translate(phys_seg_t *pseg, blkif_t *blkif, int operation)
 #define MAJOR_XEN(dev) ((dev)>>8)
 #define MINOR_XEN(dev) ((dev) & 0xff)
 
+#ifndef FANCY_REMAPPING
+static dev_t vbd_map_devnum(blkif_pdev_t cookie)
+{
+    int major = MAJOR_XEN(cookie);
+    int minor = MINOR_XEN(cookie);
+
+    return MKDEV(major, minor);
+}
+#else
 #define        XEN_IDE0_MAJOR IDE0_MAJOR
 #define        XEN_IDE1_MAJOR IDE1_MAJOR
 #define        XEN_IDE2_MAJOR IDE2_MAJOR
@@ -538,3 +561,4 @@ static dev_t vbd_map_devnum(blkif_pdev_t cookie)
 
     return MKDEV(new_major, minor);
 }
+#endif