Archipelago » blktap-utils

/* 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 <sys/time.h>

#include <xenctrl.h>

#include <xen/io/blkif.h>

#ifdef TAPDISK

#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))

#endif

#define BLK_RING_SIZE __RING_SIZE((blkif_sring_t *)0, 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

/* Abitrary values, must match the underlying driver... */

#define MAX_TAP_DEV 1024

/* 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__ */