2 * This program is free software; you can redistribute it and/or
3 * modify it under the terms of the GNU General Public License version 2
4 * as published by the Free Software Foundation; or, when distributed
5 * separately from the Linux kernel or incorporated into other
6 * software packages, subject to the following license:
8 * Permission is hereby granted, free of charge, to any person obtaining a copy
9 * of this source file (the "Software"), to deal in the Software without
10 * restriction, including without limitation the rights to use, copy, modify,
11 * merge, publish, distribute, sublicense, and/or sell copies of the Software,
12 * and to permit persons to whom the Software is furnished to do so, subject to
13 * the following conditions:
15 * The above copyright notice and this permission notice shall be included in
16 * all copies or substantial portions of the Software.
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
21 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
23 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
27 #ifndef __BLKIF__BACKEND__COMMON_H__
28 #define __BLKIF__BACKEND__COMMON_H__
30 #include <linux/version.h>
31 #include <linux/module.h>
32 #include <linux/interrupt.h>
33 #include <linux/slab.h>
34 #include <linux/blkdev.h>
35 #include <linux/vmalloc.h>
36 #include <linux/wait.h>
38 #include <asm/setup.h>
39 #include <asm/pgalloc.h>
40 #include <asm/hypervisor.h>
41 #include <xen/blkif.h>
42 #include <xen/grant_table.h>
43 #include <xen/xenbus.h>
45 #define DRV_PFX "xen-blkback:"
46 #define DPRINTK(fmt, args...) \
47 pr_debug(DRV_PFX "(%s:%d) " fmt ".\n", \
48 __func__, __LINE__, ##args)
51 /* What the domain refers to this vbd as. */
53 /* Non-zero -> read-only */
54 unsigned char readonly;
57 /* phys device that this vbd maps to. */
59 struct block_device *bdev;
60 /* Cached size parameter. */
68 /* Unique identifier for this interface. */
71 /* Physical parameters of the comms window. */
73 /* Comms information. */
74 enum blkif_protocol blk_protocol;
75 union blkif_back_rings blk_rings;
76 struct vm_struct *blk_ring_area;
77 /* The VBD attached to this interface. */
79 /* Back pointer to the backend_info. */
80 struct backend_info *be;
82 spinlock_t blk_ring_lock;
86 /* One thread per one blkif. */
87 struct task_struct *xenblkd;
88 unsigned int waiting_reqs;
91 unsigned long st_print;
99 wait_queue_head_t waiting_to_free;
101 grant_handle_t shmem_handle;
102 grant_ref_t shmem_ref;
106 #define vbd_sz(_v) ((_v)->bdev->bd_part ? \
107 (_v)->bdev->bd_part->nr_sects : \
108 get_capacity((_v)->bdev->bd_disk))
110 #define xen_blkif_get(_b) (atomic_inc(&(_b)->refcnt))
111 #define xen_blkif_put(_b) \
113 if (atomic_dec_and_test(&(_b)->refcnt)) \
114 wake_up(&(_b)->waiting_to_free);\
119 unsigned short nr_sects;
120 struct block_device *bdev;
121 blkif_sector_t sector_number;
123 int xen_blkif_interface_init(void);
125 int xen_blkif_xenbus_init(void);
127 irqreturn_t xen_blkif_be_int(int irq, void *dev_id);
128 int xen_blkif_schedule(void *arg);
130 int xen_blkbk_flush_diskcache(struct xenbus_transaction xbt,
131 struct backend_info *be, int state);
133 struct xenbus_device *xen_blkbk_xenbus(struct backend_info *be);
135 #endif /* __BLKIF__BACKEND__COMMON_H__ */