ia64/linux-2.6.18-xen.hg

view drivers/xen/blkback/vbd.c @ 521:e5f0712d7520

blkback: Set the VDISK_CDROM flag when a device is marked as being a
cdrom, even if the underlying device/file is not a physical cdrom.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
CC: Christian Limpach <christian.limpach@citrix.com>
author Keir Fraser <keir.fraser@citrix.com>
date Tue Apr 15 15:16:28 2008 +0100 (2008-04-15)
parents a533be77c572
children 271d9b9bee40
line source
1 /******************************************************************************
2 * blkback/vbd.c
3 *
4 * Routines for managing virtual block devices (VBDs).
5 *
6 * Copyright (c) 2003-2005, Keir Fraser & Steve Hand
7 *
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:
13 *
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:
20 *
21 * The above copyright notice and this permission notice shall be included in
22 * all copies or substantial portions of the Software.
23 *
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
30 * IN THE SOFTWARE.
31 */
33 #include "common.h"
35 #define vbd_sz(_v) ((_v)->bdev->bd_part ? \
36 (_v)->bdev->bd_part->nr_sects : (_v)->bdev->bd_disk->capacity)
38 unsigned long long vbd_size(struct vbd *vbd)
39 {
40 return vbd_sz(vbd);
41 }
43 unsigned int vbd_info(struct vbd *vbd)
44 {
45 return vbd->type | (vbd->readonly?VDISK_READONLY:0);
46 }
48 unsigned long vbd_secsize(struct vbd *vbd)
49 {
50 return bdev_hardsect_size(vbd->bdev);
51 }
53 int vbd_create(blkif_t *blkif, blkif_vdev_t handle, unsigned major,
54 unsigned minor, int readonly, int cdrom)
55 {
56 struct vbd *vbd;
57 struct block_device *bdev;
59 vbd = &blkif->vbd;
60 vbd->handle = handle;
61 vbd->readonly = readonly;
62 vbd->type = 0;
64 vbd->pdevice = MKDEV(major, minor);
66 bdev = open_by_devnum(vbd->pdevice,
67 vbd->readonly ? FMODE_READ : FMODE_WRITE);
69 if (IS_ERR(bdev)) {
70 DPRINTK("vbd_creat: device %08x could not be opened.\n",
71 vbd->pdevice);
72 return -ENOENT;
73 }
75 vbd->bdev = bdev;
77 if (vbd->bdev->bd_disk == NULL) {
78 DPRINTK("vbd_creat: device %08x doesn't exist.\n",
79 vbd->pdevice);
80 vbd_free(vbd);
81 return -ENOENT;
82 }
84 if (vbd->bdev->bd_disk->flags & GENHD_FL_CD || cdrom)
85 vbd->type |= VDISK_CDROM;
86 if (vbd->bdev->bd_disk->flags & GENHD_FL_REMOVABLE)
87 vbd->type |= VDISK_REMOVABLE;
89 DPRINTK("Successful creation of handle=%04x (dom=%u)\n",
90 handle, blkif->domid);
91 return 0;
92 }
94 void vbd_free(struct vbd *vbd)
95 {
96 if (vbd->bdev)
97 blkdev_put(vbd->bdev);
98 vbd->bdev = NULL;
99 }
101 int vbd_translate(struct phys_req *req, blkif_t *blkif, int operation)
102 {
103 struct vbd *vbd = &blkif->vbd;
104 int rc = -EACCES;
106 if ((operation != READ) && vbd->readonly)
107 goto out;
109 if (unlikely((req->sector_number + req->nr_sects) > vbd_sz(vbd)))
110 goto out;
112 req->dev = vbd->pdevice;
113 req->bdev = vbd->bdev;
114 rc = 0;
116 out:
117 return rc;
118 }