2011-02-28 19:41:14 -08:00

251 lines
7.0 KiB
C

/* blktaplib.h
*
* Blktap library userspace code.
*
* Copyright (c) 2007, XenSource Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of XenSource Inc. nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
* OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef __BLKTAPLIB_H__
#define __BLKTAPLIB_H__
#include <syslog.h>
#include <xenctrl.h>
#include <xen/io/blkif.h>
#if 1
#define DPRINTF(_f, _a...) syslog(LOG_INFO, _f, ##_a)
#else
#define DPRINTF(_f, _a...) ((void)0)
#endif
#define EPRINTF(_f, _a...) syslog(LOG_ERR, "tap-err:%s: " _f, __func__, ##_a)
#define PERROR(_f, _a...) EPRINTF(_f ": %s", ##_a, strerror(errno))
#define BLK_RING_SIZE __CONST_RING_SIZE(blkif, XC_PAGE_SIZE)
/* size of the extra VMA area to map in attached pages. */
#define BLKTAP_VMA_PAGES BLK_RING_SIZE
/* blktap IOCTLs: These must correspond with the blktap driver ioctls */
#define BLKTAP_IOCTL_KICK_FE 1
#define BLKTAP_IOCTL_KICK_BE 2
#define BLKTAP_IOCTL_SETMODE 3
#define BLKTAP_IOCTL_SENDPID 4
#define BLKTAP_IOCTL_NEWINTF 5
#define BLKTAP_IOCTL_MINOR 6
#define BLKTAP_IOCTL_MAJOR 7
#define BLKTAP_QUERY_ALLOC_REQS 8
#define BLKTAP_IOCTL_FREEINTF 9
#define BLKTAP_IOCTL_PRINT_IDXS 100
#define BLKTAP_IOCTL_BACKDEV_SETUP 200
#define PRIO_SPECIAL_IO -9999
/* blktap switching modes: (Set with BLKTAP_IOCTL_SETMODE) */
#define BLKTAP_MODE_PASSTHROUGH 0x00000000 /* default */
#define BLKTAP_MODE_INTERCEPT_FE 0x00000001
#define BLKTAP_MODE_INTERCEPT_BE 0x00000002
#define BLKTAP_MODE_INTERPOSE \
(BLKTAP_MODE_INTERCEPT_FE | BLKTAP_MODE_INTERCEPT_BE)
static inline int BLKTAP_MODE_VALID(unsigned long arg)
{
return (
( arg == BLKTAP_MODE_PASSTHROUGH ) ||
( arg == BLKTAP_MODE_INTERCEPT_FE ) ||
( arg == BLKTAP_MODE_INTERPOSE ) );
}
#define MAX_REQUESTS BLK_RING_SIZE
#define BLKTAP_IOCTL_KICK 1
#define MAX_PENDING_REQS BLK_RING_SIZE
#define BLKTAP_DEV_DIR "/dev/xen"
#define BLKTAP_DEV_NAME "blktap"
#define BACKDEV_NAME "backdev"
#define BLKTAP_DEV_MINOR 0
#define BLKTAP_CTRL_DIR "/var/run/tap"
extern int blktap_major;
#define BLKTAP_RING_PAGES 1 /* Front */
#define BLKTAP_MMAP_REGION_SIZE (BLKTAP_RING_PAGES + MMAP_PAGES)
struct blkif;
struct blkif_info;
typedef struct {
blkif_request_t req;
int submitting;
int secs_pending;
int16_t status;
int num_retries;
struct timeval last_try;
} pending_req_t;
typedef struct blkif {
domid_t domid;
long int handle;
long int pdev;
long int readonly;
enum { DISCONNECTED, DISCONNECTING, CONNECTED } state;
struct blkif_ops *ops;
struct blkif *hash_next;
void *prv; /* device-specific data */
struct blkif_info *info; /*Image parameter passing */
pending_req_t pending_list[MAX_REQUESTS];
int devnum;
int fds[2];
int be_id;
char *backend_path;
int major;
int minor;
pid_t tappid;
int drivertype;
uint16_t cookie;
int err;
} blkif_t;
typedef struct blkif_info {
char *params;
int readonly;
int storage;
} blkif_info_t;
typedef struct tapdev_info {
int fd;
char *mem;
blkif_sring_t *sring;
blkif_back_ring_t fe_ring;
unsigned long vstart;
blkif_t *blkif;
} tapdev_info_t;
typedef struct domid_translate {
unsigned short domid;
unsigned short busid;
} domid_translate_t ;
typedef struct image {
unsigned long long size;
unsigned long secsize;
unsigned int info;
} image_t;
typedef struct msg_hdr {
uint16_t type;
uint16_t len;
uint16_t drivertype;
uint16_t cookie;
} msg_hdr_t;
typedef struct msg_params {
uint8_t readonly;
int path_off;
int path_len;
int storage;
} msg_params_t;
typedef struct msg_newdev {
uint8_t devnum;
uint16_t domid;
} msg_newdev_t;
typedef struct msg_pid {
pid_t pid;
} msg_pid_t;
typedef struct msg_cp {
int cp_uuid_off;
int cp_uuid_len;
int cp_drivertype;
} msg_cp_t;
typedef struct msg_lock {
int ro;
int enforce;
int uuid_off;
int uuid_len;
} msg_lock_t;
#define READ 0
#define WRITE 1
/*Control Messages between manager and tapdev*/
#define CTLMSG_PARAMS 1
#define CTLMSG_IMG 2
#define CTLMSG_IMG_FAIL 3
#define CTLMSG_NEWDEV 4
#define CTLMSG_NEWDEV_RSP 5
#define CTLMSG_NEWDEV_FAIL 6
#define CTLMSG_CLOSE 7
#define CTLMSG_CLOSE_RSP 8
#define CTLMSG_PID 9
#define CTLMSG_PID_RSP 10
#define CTLMSG_CHECKPOINT 11
#define CTLMSG_CHECKPOINT_RSP 12
#define CTLMSG_LOCK 13
#define CTLMSG_LOCK_RSP 14
#define CTLMSG_PAUSE 15
#define CTLMSG_PAUSE_RSP 16
#define CTLMSG_RESUME 17
#define CTLMSG_RESUME_RSP 18
#define TAPDISK_STORAGE_TYPE_NFS 1
#define TAPDISK_STORAGE_TYPE_EXT 2
#define TAPDISK_STORAGE_TYPE_LVM 3
#define TAPDISK_STORAGE_TYPE_DEFAULT TAPDISK_STORAGE_TYPE_EXT
/* Abitrary values, must match the underlying driver... */
#define MAX_TAP_DEV 256
/* Accessing attached data page mappings */
#define MMAP_PAGES \
(MAX_PENDING_REQS * BLKIF_MAX_SEGMENTS_PER_REQUEST)
#define MMAP_VADDR(_vstart,_req,_seg) \
((_vstart) + \
((_req) * BLKIF_MAX_SEGMENTS_PER_REQUEST * getpagesize()) + \
((_seg) * getpagesize()))
/* Defines that are only used by library clients */
#ifndef __COMPILING_BLKTAP_LIB
static char *blkif_op_name[] = {
[BLKIF_OP_READ] = "READ",
[BLKIF_OP_WRITE] = "WRITE",
};
#endif /* __COMPILING_BLKTAP_LIB */
#endif /* __BLKTAPLIB_H__ */