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
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35 #define vbd_sz(_v) ((_v)->bdev->bd_part ? \
36 (_v)->bdev->bd_part->nr_sects : get_capacity((_v)->bdev->bd_disk))
38 unsigned long long vbd_size(struct vbd *vbd)
43 unsigned int vbd_info(struct vbd *vbd)
45 return vbd->type | (vbd->readonly?VDISK_READONLY:0);
48 unsigned long vbd_secsize(struct vbd *vbd)
50 return bdev_logical_block_size(vbd->bdev);
53 int vbd_create(blkif_t *blkif, blkif_vdev_t handle, unsigned major,
54 unsigned minor, int readonly, int cdrom)
57 struct block_device *bdev;
61 vbd->readonly = readonly;
64 vbd->pdevice = MKDEV(major, minor);
66 bdev = open_by_devnum(vbd->pdevice,
67 vbd->readonly ? FMODE_READ : FMODE_WRITE);
70 DPRINTK("vbd_creat: device %08x could not be opened.\n",
77 if (vbd->bdev->bd_disk == NULL) {
78 DPRINTK("vbd_creat: device %08x doesn't exist.\n",
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);
94 void vbd_free(struct vbd *vbd)
97 blkdev_put(vbd->bdev, vbd->readonly ? FMODE_READ : FMODE_WRITE);
101 int vbd_translate(struct phys_req *req, blkif_t *blkif, int operation)
103 struct vbd *vbd = &blkif->vbd;
106 if ((operation != READ) && vbd->readonly)
109 if (unlikely((req->sector_number + req->nr_sects) > vbd_sz(vbd)))
112 req->dev = vbd->pdevice;
113 req->bdev = vbd->bdev;