1 /******************************************************************************
2 * Routines for managing virtual block devices (VBDs).
4 * Copyright (c) 2003-2005, Keir Fraser & Steve Hand
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License version 2
8 * as published by the Free Software Foundation; or, when distributed
9 * separately from the Linux kernel or incorporated into other
10 * software packages, subject to the following license:
12 * Permission is hereby granted, free of charge, to any person obtaining a copy
13 * of this source file (the "Software"), to deal in the Software without
14 * restriction, including without limitation the rights to use, copy, modify,
15 * merge, publish, distribute, sublicense, and/or sell copies of the Software,
16 * and to permit persons to whom the Software is furnished to do so, subject to
17 * the following conditions:
19 * The above copyright notice and this permission notice shall be included in
20 * all copies or substantial portions of the Software.
22 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
23 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
24 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
25 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
26 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
27 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
33 #define vbd_sz(_v) ((_v)->bdev->bd_part ? \
34 (_v)->bdev->bd_part->nr_sects : \
35 get_capacity((_v)->bdev->bd_disk))
37 unsigned long long vbd_size(struct vbd *vbd)
42 unsigned int vbd_info(struct vbd *vbd)
44 return vbd->type | (vbd->readonly ? VDISK_READONLY : 0);
47 unsigned long vbd_secsize(struct vbd *vbd)
49 return bdev_logical_block_size(vbd->bdev);
52 int vbd_create(struct blkif_st *blkif, blkif_vdev_t handle, unsigned major,
53 unsigned minor, int readonly, int cdrom)
56 struct block_device *bdev;
60 vbd->readonly = readonly;
63 vbd->pdevice = MKDEV(major, minor);
65 bdev = blkdev_get_by_dev(vbd->pdevice, vbd->readonly ?
66 FMODE_READ : FMODE_WRITE, NULL);
69 DPRINTK("vbd_creat: device %08x could not be opened.\n",
75 vbd->size = vbd_size(vbd);
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, struct blkif_st *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;
120 void vbd_resize(struct blkif_st *blkif)
122 struct vbd *vbd = &blkif->vbd;
123 struct xenbus_transaction xbt;
125 struct xenbus_device *dev = blkback_xenbus(blkif->be);
126 unsigned long long new_size = vbd_size(vbd);
128 printk(KERN_INFO "VBD Resize: Domid: %d, Device: (%d, %d)\n",
129 blkif->domid, MAJOR(vbd->pdevice), MINOR(vbd->pdevice));
130 printk(KERN_INFO "VBD Resize: new size %llu\n", new_size);
131 vbd->size = new_size;
133 err = xenbus_transaction_start(&xbt);
135 printk(KERN_WARNING "Error starting transaction");
138 err = xenbus_printf(xbt, dev->nodename, "sectors", "%llu",
141 printk(KERN_WARNING "Error writing new size");
145 * Write the current state; we will use this to synchronize
146 * the front-end. If the current state is "connected" the
147 * front-end will get the new size information online.
149 err = xenbus_printf(xbt, dev->nodename, "state", "%d", dev->state);
151 printk(KERN_WARNING "Error writing the state");
155 err = xenbus_transaction_end(xbt, 0);
159 printk(KERN_WARNING "Error ending transaction");
161 xenbus_transaction_end(xbt, 1);