OpenCloudOS-Kernel/drivers/block/xen-blkback/common.h

143 lines
4.5 KiB
C

/*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation; or, when distributed
* separately from the Linux kernel or incorporated into other
* software packages, subject to the following license:
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this source file (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software,
* and to permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*/
#ifndef __BLKIF__BACKEND__COMMON_H__
#define __BLKIF__BACKEND__COMMON_H__
#include <linux/version.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/blkdev.h>
#include <linux/vmalloc.h>
#include <linux/wait.h>
#include <linux/io.h>
#include <asm/setup.h>
#include <asm/pgalloc.h>
#include <asm/hypervisor.h>
#include <xen/blkif.h>
#include <xen/grant_table.h>
#include <xen/xenbus.h>
#define DPRINTK(_f, _a...) \
pr_debug("(file=%s, line=%d) " _f, \
__FILE__ , __LINE__ , ## _a)
struct vbd {
blkif_vdev_t handle; /* what the domain refers to this vbd as */
unsigned char readonly; /* Non-zero -> read-only */
unsigned char type; /* VDISK_xxx */
u32 pdevice; /* phys device that this vbd maps to */
struct block_device *bdev;
sector_t size; /* Cached size parameter */
};
struct backend_info;
struct blkif_st {
/* Unique identifier for this interface. */
domid_t domid;
unsigned int handle;
/* Physical parameters of the comms window. */
unsigned int irq;
/* Comms information. */
enum blkif_protocol blk_protocol;
union blkif_back_rings blk_rings;
struct vm_struct *blk_ring_area;
/* The VBD attached to this interface. */
struct vbd vbd;
/* Back pointer to the backend_info. */
struct backend_info *be;
/* Private fields. */
spinlock_t blk_ring_lock;
atomic_t refcnt;
wait_queue_head_t wq;
/* One thread per one blkif. */
struct task_struct *xenblkd;
unsigned int waiting_reqs;
/* statistics */
unsigned long st_print;
int st_rd_req;
int st_wr_req;
int st_oo_req;
int st_br_req;
int st_rd_sect;
int st_wr_sect;
wait_queue_head_t waiting_to_free;
grant_handle_t shmem_handle;
grant_ref_t shmem_ref;
};
struct blkif_st *blkif_alloc(domid_t domid);
void blkif_disconnect(struct blkif_st *blkif);
void blkif_free(struct blkif_st *blkif);
int blkif_map(struct blkif_st *blkif, unsigned long shared_page,
unsigned int evtchn);
void vbd_resize(struct blkif_st *blkif);
#define blkif_get(_b) (atomic_inc(&(_b)->refcnt))
#define blkif_put(_b) \
do { \
if (atomic_dec_and_test(&(_b)->refcnt)) \
wake_up(&(_b)->waiting_to_free);\
} while (0)
/* Create a vbd. */
int vbd_create(struct blkif_st *blkif, blkif_vdev_t vdevice, unsigned major,
unsigned minor, int readonly, int cdrom);
void vbd_free(struct vbd *vbd);
unsigned long long vbd_size(struct vbd *vbd);
unsigned int vbd_info(struct vbd *vbd);
unsigned long vbd_secsize(struct vbd *vbd);
struct phys_req {
unsigned short dev;
unsigned short nr_sects;
struct block_device *bdev;
blkif_sector_t sector_number;
};
int vbd_translate(struct phys_req *req, struct blkif_st *blkif, int operation);
int blkif_interface_init(void);
int blkif_xenbus_init(void);
irqreturn_t blkif_be_int(int irq, void *dev_id);
int blkif_schedule(void *arg);
int blkback_barrier(struct xenbus_transaction xbt,
struct backend_info *be, int state);
struct xenbus_device *blkback_xenbus(struct backend_info *be);
#endif /* __BLKIF__BACKEND__COMMON_H__ */