1 /******************************************************************************
4 * Routines for managing virtual block devices (VBDs).
6 * Copyright (c) 2003-2005, Keir Fraser & Steve Hand
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License version 2
10 * as published by the Free Software Foundation; or, when distributed
11 * separately from the Linux kernel or incorporated into other
12 * software packages, subject to the following license:
14 * Permission is hereby granted, free of charge, to any person obtaining a copy
15 * of this source file (the "Software"), to deal in the Software without
16 * restriction, including without limitation the rights to use, copy, modify,
17 * merge, publish, distribute, sublicense, and/or sell copies of the Software,
18 * and to permit persons to whom the Software is furnished to do so, subject to
19 * the following conditions:
21 * The above copyright notice and this permission notice shall be included in
22 * all copies or substantial portions of the Software.
24 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
25 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
26 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
27 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
28 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
29 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
34 #include <xen/xenbus.h>
36 #define vbd_sz(_v) ((_v)->bdev->bd_part ? \
37 (_v)->bdev->bd_part->nr_sects : (_v)->bdev->bd_disk->capacity)
39 unsigned long vbd_size(struct vbd *vbd)
44 unsigned int vbd_info(struct vbd *vbd)
46 return vbd->type | (vbd->readonly?VDISK_READONLY:0);
49 unsigned long vbd_secsize(struct vbd *vbd)
51 return bdev_hardsect_size(vbd->bdev);
54 int vbd_create(blkif_t *blkif, blkif_vdev_t handle, unsigned major,
55 unsigned minor, int readonly)
58 struct block_device *bdev;
62 vbd->readonly = readonly;
65 vbd->pdevice = MKDEV(major, minor);
67 bdev = open_by_devnum(vbd->pdevice,
68 vbd->readonly ? FMODE_READ : FMODE_WRITE);
71 DPRINTK("vbd_creat: device %08x could not be opened.\n",
78 if (vbd->bdev->bd_disk == NULL) {
79 DPRINTK("vbd_creat: device %08x doesn't exist.\n",
85 if (vbd->bdev->bd_disk->flags & GENHD_FL_CD)
86 vbd->type |= VDISK_CDROM;
87 if (vbd->bdev->bd_disk->flags & GENHD_FL_REMOVABLE)
88 vbd->type |= VDISK_REMOVABLE;
90 DPRINTK("Successful creation of handle=%04x (dom=%u)\n",
91 handle, blkif->domid);
95 void vbd_free(struct vbd *vbd)
98 blkdev_put(vbd->bdev);
102 int vbd_translate(struct phys_req *req, blkif_t *blkif, int operation)
104 struct vbd *vbd = &blkif->vbd;
107 if ((operation == WRITE) && vbd->readonly)
110 if (unlikely((req->sector_number + req->nr_sects) > vbd_sz(vbd)))
113 req->dev = vbd->pdevice;
114 req->bdev = vbd->bdev;