minix/servers/rs/type.h
Cristiano Giuffrida cb176df60f New RS and new signal handling for system processes.
UPDATING INFO:
20100317:
        /usr/src/etc/system.conf updated to ignore default kernel calls: copy
        it (or merge it) to /etc/system.conf.
        The hello driver (/dev/hello) added to the distribution:
        # cd /usr/src/commands/scripts && make clean install
        # cd /dev && MAKEDEV hello

KERNEL CHANGES:
- Generic signal handling support. The kernel no longer assumes PM as a signal
manager for every process. The signal manager of a given process can now be
specified in its privilege slot. When a signal has to be delivered, the kernel
performs the lookup and forwards the signal to the appropriate signal manager.
PM is the default signal manager for user processes, RS is the default signal
manager for system processes. To enable ptrace()ing for system processes, it
is sufficient to change the default signal manager to PM. This will temporarily
disable crash recovery, though.
- sys_exit() is now split into sys_exit() (i.e. exit() for system processes,
which generates a self-termination signal), and sys_clear() (i.e. used by PM
to ask the kernel to clear a process slot when a process exits).
- Added a new kernel call (i.e. sys_update()) to swap two process slots and
implement live update.

PM CHANGES:
- Posix signal handling is no longer allowed for system processes. System
signals are split into two fixed categories: termination and non-termination
signals. When a non-termination signaled is processed, PM transforms the signal
into an IPC message and delivers the message to the system process. When a
termination signal is processed, PM terminates the process.
- PM no longer assumes itself as the signal manager for system processes. It now
makes sure that every system signal goes through the kernel before being
actually processes. The kernel will then dispatch the signal to the appropriate
signal manager which may or may not be PM.

SYSLIB CHANGES:
- Simplified SEF init and LU callbacks.
- Added additional predefined SEF callbacks to debug crash recovery and
live update.
- Fixed a temporary ack in the SEF init protocol. SEF init reply is now
completely synchronous.
- Added SEF signal event type to provide a uniform interface for system
processes to deal with signals. A sef_cb_signal_handler() callback is
available for system processes to handle every received signal. A
sef_cb_signal_manager() callback is used by signal managers to process
system signals on behalf of the kernel.
- Fixed a few bugs with memory mapping and DS.

VM CHANGES:
- Page faults and memory requests coming from the kernel are now implemented
using signals.
- Added a new VM call to swap two process slots and implement live update.
- The call is used by RS at update time and in turn invokes the kernel call
sys_update().

RS CHANGES:
- RS has been reworked with a better functional decomposition.
- Better kernel call masks. com.h now defines the set of very basic kernel calls
every system service is allowed to use. This makes system.conf simpler and
easier to maintain. In addition, this guarantees a higher level of isolation
for system libraries that use one or more kernel calls internally (e.g. printf).
- RS is the default signal manager for system processes. By default, RS
intercepts every signal delivered to every system process. This makes crash
recovery possible before bringing PM and friends in the loop.
- RS now supports fast rollback when something goes wrong while initializing
the new version during a live update.
- Live update is now implemented by keeping the two versions side-by-side and
swapping the process slots when the old version is ready to update.
- Crash recovery is now implemented by keeping the two versions side-by-side
and cleaning up the old version only when the recovery process is complete.

DS CHANGES:
- Fixed a bug when the process doing ds_publish() or ds_delete() is not known
by DS.
- Fixed the completely broken support for strings. String publishing is now
implemented in the system library and simply wraps publishing of memory ranges.
Ideally, we should adopt a similar approach for other data types as well.
- Test suite fixed.

DRIVER CHANGES:
- The hello driver has been added to the Minix distribution to demonstrate basic
live update and crash recovery functionalities.
- Other drivers have been adapted to conform the new SEF interface.
2010-03-17 01:15:29 +00:00

84 lines
3.2 KiB
C

/* Type definitions used in RS.
*/
#ifndef RS_TYPE_H
#define RS_TYPE_H
/* Definition of an entry of the boot image priv table. */
struct boot_image_priv {
endpoint_t endpoint; /* process endpoint number */
char label[RS_MAX_LABEL_LEN]; /* label to assign to this service */
int flags; /* privilege flags */
short trap_mask; /* allowed system call traps */
int ipc_to; /* send mask protection */
endpoint_t sig_mgr; /* signal manager */
int *k_calls; /* allowed kernel calls */
int *vm_calls; /* allowed vm calls */
};
/* Definition of an entry of the boot image sys table. */
struct boot_image_sys {
endpoint_t endpoint; /* process endpoint number */
int flags; /* system flags */
};
/* Definition of an entry of the boot image dev table. */
struct boot_image_dev {
endpoint_t endpoint; /* process endpoint number */
dev_t dev_nr; /* major device number */
int dev_style; /* device style */
long period; /* heartbeat period (or zero) */
};
/* Definition of an entry of the system process table. */
struct rproc {
struct rprocpub *r_pub; /* pointer to the corresponding public entry */
struct rproc *r_old_rp; /* pointer to the slot with the old version */
struct rproc *r_new_rp; /* pointer to the slot with the new version */
struct rproc *r_prev_rp; /* pointer to the slot with the prev replica */
struct rproc *r_next_rp; /* pointer to the slot with the next replica */
pid_t r_pid; /* process id, -1 if the process is not there */
int r_restarts; /* number of restarts (initially zero) */
long r_backoff; /* number of periods to wait before revive */
unsigned r_flags; /* status and policy flags */
clock_t r_check_tm; /* timestamp of last check */
clock_t r_alive_tm; /* timestamp of last heartbeat */
clock_t r_stop_tm; /* timestamp of SIGTERM signal */
endpoint_t r_caller; /* RS_LATEREPLY caller */
int r_caller_request; /* RS_LATEREPLY caller request */
char r_cmd[MAX_COMMAND_LEN]; /* raw command plus arguments */
char r_args[MAX_COMMAND_LEN]; /* null-separated raw command plus arguments */
char *r_argv[MAX_NR_ARGS+2]; /* parsed arguments vector */
int r_argc; /* number of arguments */
char r_script[MAX_SCRIPT_LEN]; /* name of the restart script executable */
char *r_exec; /* Executable image */
size_t r_exec_len; /* Length of image */
int r_set_resources; /* set when resources must be set. */
struct priv r_priv; /* Privilege structure to be passed to the
* kernel.
*/
uid_t r_uid;
int r_nice;
char r_ipc_list[MAX_IPC_LIST];
int r_nr_control;
char r_control[RS_NR_CONTROL][RS_MAX_LABEL_LEN];
};
/* Definition of the global update descriptor. */
struct rupdate {
int flags; /* flags to keep track of the status of the update */
clock_t prepare_tm; /* timestamp of when the update was scheduled */
clock_t prepare_maxtime; /* max time to wait for the process to be ready */
struct rproc *rp; /* the process under update */
};
#endif /* RS_TYPE_H */