minix/drivers/filter/inc.h
Cristiano Giuffrida 48c6bb79f4 Driver refactory for live update and crash recovery.
SYSLIB CHANGES:
- DS calls to publish / retrieve labels consider endpoints instead of u32_t.

VFS CHANGES:
- mapdriver() only adds an entry in the dmap table in VFS.
- dev_up() is only executed upon reception of a driver up event.

INET CHANGES:
- INET no longer searches for existing drivers instances at startup.
- A newtwork driver is (re)initialized upon reception of a driver up event.
- Networking startup is now race-free by design. No need to waste 5 seconds
at startup any more.

DRIVER CHANGES:
- Every driver publishes driver up events when starting for the first time or
in case of restart when recovery actions must be taken in the upper layers.
- Driver up events are published by drivers through DS. 
- For regular drivers, VFS is normally the only subscriber, but not necessarily.
For instance, when the filter driver is in use, it must subscribe to driver
up events to initiate recovery.
- For network drivers, inet is the only subscriber for now.
- Every VFS driver is statically linked with libdriver, every network driver
is statically linked with libnetdriver.

DRIVER LIBRARIES CHANGES:
- Libdriver is extended to provide generic receive() and ds_publish() interfaces
for VFS drivers.
- driver_receive() is a wrapper for sef_receive() also used in driver_task()
to discard spurious messages that were meant to be delivered to a previous
version of the driver.
- driver_receive_mq() is the same as driver_receive() but integrates support
for queued messages.
- driver_announce() publishes a driver up event for VFS drivers and marks
the driver as initialized and expecting a DEV_OPEN message.
- Libnetdriver is introduced to provide similar receive() and ds_publish()
interfaces for network drivers (netdriver_announce() and netdriver_receive()).
- Network drivers all support live update with no state transfer now.

KERNEL CHANGES:
- Added kernel call statectl for state management. Used by driver_announce() to
unblock eventual callers sendrecing to the driver.
2010-04-08 13:41:35 +00:00

122 lines
2.9 KiB
C

/* Filter driver - general include file */
#define _MINIX 1
#define _SYSTEM 1
#include <minix/config.h>
#include <minix/const.h>
#include <minix/type.h>
#include <minix/com.h>
#include <minix/ipc.h>
#include <sys/ioc_disk.h>
#include <minix/sysutil.h>
#include <minix/syslib.h>
#include <minix/partition.h>
#include <minix/ds.h>
#include <minix/callnr.h>
#include <minix/driver.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#define SECTOR_SIZE 512
typedef enum {
ST_NIL, /* Zero checksums */
ST_XOR, /* XOR-based checksums */
ST_CRC, /* CRC32-based checksums */
ST_MD5 /* MD5-based checksums */
} checksum_type;
typedef enum {
FLT_WRITE, /* write to up to two disks */
FLT_READ, /* read from one disk */
FLT_READ2 /* read from both disks */
} disk_operation;
struct driverinfo {
char *label;
int minor;
endpoint_t endpt;
int up_event;
int problem; /* one of BD_* */
int error; /* one of E*, only relevant if problem>0 */
int retries;
int kills;
};
/* UP event characterization. */
#define UP_EXPECTED 0
#define UP_NONE 1
#define UP_PENDING 2
/* Something was wrong and the disk driver has been restarted/refreshed,
* so the request needs to be redone.
*/
#define RET_REDO 1
/* The cases where the disk driver need to be restarted/refreshed by RS.
* BD_DEAD: the disk driver has died. Restart it.
* BD_PROTO: a protocol error has occurred. Refresh it.
* BD_DATA: a data error has occurred. Refresh it.
*/
typedef enum {
BD_NONE,
BD_DEAD,
BD_PROTO,
BD_DATA,
BD_LAST
} driver_state;
#define DRIVER_MAIN 0
#define DRIVER_BACKUP 1
/* Requests for more than this many bytes will be allocated dynamically. */
#define BUF_SIZE (256 * 1024)
#define SBUF_SIZE (BUF_SIZE * 2)
#define LABEL_SIZE 32
typedef unsigned long sector_t;
/* main.c */
extern int USE_CHECKSUM;
extern int USE_MIRROR;
extern int BAD_SUM_ERROR;
extern int USE_SUM_LAYOUT;
extern int SUM_TYPE;
extern int SUM_SIZE;
extern int NR_SUM_SEC;
extern int NR_RETRIES;
extern int NR_RESTARTS;
extern int DRIVER_TIMEOUT;
extern int CHUNK_SIZE;
extern char MAIN_LABEL[LABEL_SIZE];
extern char BACKUP_LABEL[LABEL_SIZE];
extern int MAIN_MINOR;
extern int BACKUP_MINOR;
/* sum.c */
extern void sum_init(void);
extern int transfer(u64_t pos, char *buffer, size_t *sizep, int flag_rw);
extern u64_t convert(u64_t size);
/* driver.c */
extern void driver_init(void);
extern void driver_shutdown(void);
extern u64_t get_raw_size(void);
extern void reset_kills(void);
extern int check_driver(int which);
extern int bad_driver(int which, int type, int error);
extern int read_write(u64_t pos, char *bufa, char *bufb, size_t *sizep,
int flag_rw);
extern void ds_event(void);
/* util.c */
extern char *flt_malloc(size_t size, char *sbuf, size_t ssize);
extern void flt_free(char *buf, size_t size, const char *sbuf);
extern char *print64(u64_t p);
extern clock_t flt_alarm(clock_t dt);