xref: /illumos-gate/usr/src/uts/common/sys/sysevent_impl.h (revision 6a634c9d)

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
 */

#ifndef	_SYS_SYSEVENT_IMPL_H
#define	_SYS_SYSEVENT_IMPL_H

#include <sys/nvpair.h>
#include <sys/id_space.h>
#include <sys/door.h>

#ifdef	__cplusplus
extern "C" {
#endif

typedef uint64_t se_data_t;

/*
 * The following data structure assist in loading and extracting event
 * header and attribute data into contiguous memory.  Access to all typed
 * data done so on 64-bit boundaries.  *Do Not* alter any of the structures
 * defined below without thorough thought and testing.
 */

/* Attribute name */
typedef struct se_name {
	int32_t		name_sz;
	int32_t		name_pad;
	se_data_t	name;	/* 64-bit aligned offset */
} se_name_t;

/* Attribute value */
typedef struct se_value {
	int32_t		value_type;	/* data type */
	int32_t		value_sz;
	se_data_t	value;		/* data value - 64-bit aligned offset */
} se_value_t;

/* sysevent internal attribute name-value pair stored in contiguous memory */
typedef struct sysevent_attr_impl {
	int32_t		se_attr_sz;	/* Size of attribute data */
	int32_t		se_attr_pad;	/* pad */
	se_data_t	se_attr_name;	/* name of data attribute */
	se_data_t	se_attr_val;	/* value and type of data */
} sysevent_attr_impl_t;

/* Attribute list states */
#define	ATTR_DETACHED	0
#define	ATTR_ATTACHED	1

/*
 * The following type definitions describe a sysevent object that is
 * generated by a call to sysevent_alloc and sent to userland.
 */

/*
 * sysevent event header information -
 *	contained in every event generated.  The header and the event
 *	must remain 64-bit aligned.  The header, up to the attribute
 *	offset, can be contained in a single cache line.
 */
typedef struct sysevent_hdr {
	sysevent_id_t	se_id;		/* unique identifier */
	uint32_t	se_version;	/* version of this data structure */
	uint32_t	se_flag;
	uint32_t	se_class;	/* event class id - reserved */
	uint32_t	se_subclass;	/* event subclass id - reserved */
	int32_t		se_payload_sz;	/* size of attr data + strings */
	uint16_t	se_subclass_off; /* offset to subclass string */
	uint16_t	se_pub_off;	/* offset to publisher string */
	uint64_t	se_attr_off;	/* pointer or offset to attr data */
} sysevent_hdr_t;

/* sysevent event buffer - 64-bit aligned offsets */
typedef struct sys_event_impl {
	sysevent_hdr_t	se_header;
	se_data_t	se_class_name;	/* class string in contig memory */
	se_data_t	se_subclass_name; /* subclass string in contig memory */
	se_data_t	se_pub;		/* publisher string in contig mem */
	se_data_t	se_attr_buf;	/* contiguous attribute memory	*/
} sysevent_impl_t;

/* Helpful defines */
#define	seh_version	se_header.se_version
#define	seh_class	se_header.se_class
#define	seh_subclass	se_header.se_subclass
#define	seh_seq		se_header.se_id.eid_seq
#define	seh_time	se_header.se_id.eid_ts
#define	seh_subclass_off se_header.se_subclass_off
#define	seh_pub_off	se_header.se_pub_off
#define	seh_attr_off	se_header.se_attr_off
#define	seh_payload_sz	se_header.se_payload_sz
#define	seh_flag	se_header.se_flag

/* Event buffer version */
#define	SYS_EVENT_VERSION	0

/* Event buffer flags */
#define	SE_PACKED_BUF	1

#define	SYSEVENT_IMPL(ev)	((sysevent_impl_t *)(void *)(ev))
#define	SE_VERSION(ev)		(SYSEVENT_IMPL(ev)->seh_version)
#define	SE_CLASS(ev)		(SYSEVENT_IMPL(ev)->seh_class)
#define	SE_SUBCLASS(ev)		(SYSEVENT_IMPL(ev)->seh_subclass)
#define	SE_SEQ(ev)		(SYSEVENT_IMPL(ev)->seh_seq)
#define	SE_TIME(ev)		(SYSEVENT_IMPL(ev)->seh_time)
#define	SE_SUBCLASS_OFF(ev)	(SYSEVENT_IMPL(ev)->seh_subclass_off)
#define	SE_PUB_OFF(ev)		(SYSEVENT_IMPL(ev)->seh_pub_off)
#define	SE_PAYLOAD_SZ(ev)	(SYSEVENT_IMPL(ev)->seh_payload_sz)
#define	SE_FLAG(ev)		(SYSEVENT_IMPL(ev)->seh_flag)
#define	SE_SIZE(ev)		(sizeof (sysevent_impl_t) + SE_PAYLOAD_SZ(ev))
#define	SE_CLASS_NAME(ev)	((char *)&(SYSEVENT_IMPL(ev)->se_class_name))
#define	SE_SUBCLASS_NAME(ev)	((char *)((caddr_t)(ev) + SE_SUBCLASS_OFF(ev)))
#define	SE_PUB_NAME(ev)		((char *)((caddr_t)(ev) + SE_PUB_OFF(ev)))

/*
 * Attribute data can be stored in contiguous memory or
 * as a list of attribute data elements.  The storage format is determined
 * by the SE_PACKED_BUF flag in the event buffer flags.
 *
 */

/* 64-bit boundary alignment function */
#define	SE_ALIGN(x)	((((ulong_t)x) + 7ul) & ~7ul)

/* Access to unpacked attribute list */
#define	SE_ATTR_PTR(ev)		(SYSEVENT_IMPL(ev)->seh_attr_off)

/* Offset to packed attribute data */
#define	SE_ATTR_OFF(ev)	SE_PUB_OFF(ev) + SE_ALIGN(strlen(SE_PUB_NAME(ev)) + 1)

/* syseventd door */
#define	LOGEVENT_DOOR_UPCALL	"/var/run/sysevent_door"

/*
 * door upcall data structures
 */
typedef struct log_event_upcall_arg {
	int32_t retcode;
	int32_t	pad;
	sysevent_impl_t buf;
} log_event_upcall_arg_t;

typedef struct log_eventq {
	struct log_eventq	*next;
	log_event_upcall_arg_t	arg;
} log_eventq_t;

/* Syseventd Channel structures */

#define	MAX_CHAN	256	/* Maximum channels per system */
#define	MAX_SUBSCRIBERS	100	/* Maximum subscribers per channel */
#define	MAX_PUBLISHERS	1	/* Maximum publishers per channel */

/*
 * Channel-based subscription structures
 */

/* Class hashing defines */
#define	CLASS_HASH_SZ	63
#define	CLASS_HASH(class_name)	((hash_func(class_name) \
				% CLASS_HASH_SZ) + 1)
#define	CHAN_HASH_SZ	32

typedef struct subclass_lst {
	struct subclass_lst	*sl_next;
	char			*sl_name;
	uchar_t			sl_num[MAX_SUBSCRIBERS + 1];
} subclass_lst_t;

typedef struct class_lst {
	struct class_lst	*cl_next;
	char			*cl_name;
	struct subclass_lst	*cl_subclass_list;
} class_lst_t;

/* User/Kernel Structure to pass event registration modctl data */
typedef struct se_pubsub {
	uint32_t	ps_buflen;
	uint32_t	ps_channel_name_len;
	uint32_t	ps_id;
	uint32_t	ps_op;
	uint32_t	ps_type;
} se_pubsub_t;

/* op defines */
#define	SE_REGISTER		0
#define	SE_UNREGISTER		1
#define	SE_CLEANUP		2
#define	SE_OPEN_REGISTRATION	3
#define	SE_CLOSE_REGISTRATION	4
#define	SE_BIND_REGISTRATION	5
#define	SE_UNBIND_REGISTRATION	6
#define	SE_GET_REGISTRATION	7

/* type defines */
#define	SUBSCRIBER	0
#define	PUBLISHER	1

/* nvpair names */
#define	CLASS_NAME	"class"

#ifdef	_KERNEL

typedef struct sysevent_channel_descriptor {
	char   *scd_channel_name;	/* Name of channel */
	struct sysevent_channel_descriptor *scd_next;
	int    scd_ref_cnt;		/* Reference count of channel opens */
	id_space_t *scd_subscriber_cache;	/* cache of subscriber ids */
	id_space_t *scd_publisher_cache;	/* cache of publisher ids */
	uchar_t scd_subscriber_ids[MAX_SUBSCRIBERS + 1]; /* used sub ids */
	uchar_t scd_publisher_ids[MAX_PUBLISHERS + 1];	/* used  pub ids */
	class_lst_t *scd_class_list_tbl[CLASS_HASH_SZ + 1];
} sysevent_channel_descriptor_t;

/*
 * log_sysevent private interfaces
 */
extern void log_event_init(void);
extern void log_sysevent_flushq(int, uint_t);
extern int log_sysevent_filename(char *);
extern int log_usr_sysevent(sysevent_t *, int, sysevent_id_t *);
extern int log_sysevent_copyout_data(sysevent_id_t *, size_t, caddr_t);
extern int log_sysevent_free_data(sysevent_id_t *);
extern int log_sysevent_register(char *, char *, se_pubsub_t *);
extern uint64_t log_sysevent_new_id(void);

/*
 * Structures and definitions for general purpose event channels
 */

/* Limits */
#define	EVCH_MAX_CHANNELS		1024
#define	EVCH_MAX_BINDS_PER_CHANNEL	512
#define	EVCH_MAX_SUBSCRIPTIONS		32
#define	EVCH_SUBPOOLFACT		8
#define	EVCH_DEFAULT_EVENTS		2000
#define	EVCH_MAX_TRY_DELIVERY		3

/* Linkage element for evch_dlist_t lists */
typedef struct evch_dlelem {
	struct evch_dlelem	*dl_next;
	struct evch_dlelem	*dl_prev;
} evch_dlelem_t;

/* List head */
typedef struct {
	evch_dlelem_t	dh_head;
	int		dh_count;
} evch_dlist_t;

/* Placeholder for elements in a evch_squeue_t queue */
typedef struct evch_qelem {
	struct evch_qelem	*q_next;
	void			*q_objref;
	size_t			q_objsize;
} evch_qelem_t;

/* Queue head data */
typedef struct {
	evch_qelem_t	*sq_head;
	evch_qelem_t	*sq_tail;
	uint32_t	sq_count;
	uint32_t	sq_highwm;
} evch_squeue_t;

/*
 * Defines for event queue routines
 */
#define	EVQ_IGNORE	1
#define	EVQ_DELIVER	2

#define	EVQ_CONT	0
#define	EVQ_AGAIN	1
#define	EVQ_SLEEP	2

/* Call back routine typedefs */
typedef int (*filter_f)(void *, void *);
typedef int (*deliver_f)(void *, void *);
typedef int (*kerndlv_f)(void *, void *);
typedef void (*destr_f)(void *, void *);
typedef int (*compare_f)(evch_dlelem_t *, char *);

/*
 * Event structure handled by evch_evq_* functions. Sysevent type events are
 * stored as the payload.
 */
typedef struct {
	uint32_t	ge_size;	/* Total size of event structure */
	uint32_t	ge_refcount;	/* No of queues event is linked to */
	destr_f		ge_destruct;	/* Destructor for event structure */
	uint32_t	*ge_dstcookie;	/* Cookie for destructor function */
	uchar_t		ge_payload[1];	/* Placeholder for event data */
} evch_gevent_t;

/*
 * Event queue descriptor
 */
typedef struct {
	evch_squeue_t	eq_eventq;	/* Protected by eq_dtmutex */
	kt_did_t	eq_thrid;	/* Id delivery thread */
	kmutex_t	eq_queuemx;	/* Protect. of this struct and ev q */
	kcondvar_t	eq_thrsleepcv;	/* Delivery thread sleeps on empty q */
	int		eq_dactive;	/* Event delivery is in progress */
	kcondvar_t	eq_dactivecv;	/* Unsubscr. has to wait on this */
	evch_dlist_t	eq_subscr;	/* Chain of all evch_evqsub_t */
	uint32_t	eq_nsleep;	/* Statistic: Publisher set to sleep */
	int		eq_holdmode;	/* Hold event delivery */
	evch_gevent_t	*eq_curevent;	/* Event currently beeing delivered */
	evch_qelem_t	*eq_nextev;	/* For iterating over events in a q */
	kcondvar_t	eq_onholdcv;	/* To signal hold mode of deliv. thr. */
	uchar_t		eq_tabortflag;	/* Request to abort delivery thread */
} evch_eventq_t;

/*
 * Event queue per subscriber structure
 */
typedef struct {
	evch_dlelem_t	su_link;
	filter_f	su_filter;	/* Event filter function pointer */
	void		*su_fcookie;	/* cookie for event filter */
	deliver_f	su_callb;	/* Event delivery callback */
	void		*su_cbcookie;	/* callback cookie */
} evch_evqsub_t;

/* Eveny delivery type */
#define	EVCH_DELKERN		1	/* Kernel event delivery */
#define	EVCH_DELDOOR		2	/* User event delivery via doors */

/*
 * Per channel subscriber data structure. Chained in a linked list to an
 * event channel and to a binding.
 */
typedef struct chsubd {
	evch_dlelem_t	sd_link;	/* Links all subscribers of this ch. */
	struct chsubd	*sd_subnxt;	/* Links all subscr. for a binding */
	char		*sd_ident;	/* Subscriber identifier */
	evch_eventq_t	*sd_queue;	/* Event queue for this subscriber */
	evch_evqsub_t	*sd_msub;	/* Main event queue subscr. */
	char		*sd_classname;	/* Filter criteria */
	size_t		sd_clnsize;	/* Size of sd_classname buffer */
	evch_evqsub_t	*sd_ssub;	/* Subscriber queue subscr. */
	int		sd_type;	/* Type of event delivery */
	kerndlv_f	sd_callback;	/* Callback for kernel delivery */
	void		*sd_cbcookie;	/* Cookie for kernel delivery */
	door_handle_t	sd_door;	/* Door handle for user delivery */
	int		sd_active;	/* Subscription is in use indicator */
	pid_t		sd_pid;		/* PID of subscribing process */
	uint8_t		sd_persist;	/* Persistent user land subscription */
	uint8_t		sd_dump;	/* Dump with sysevent_evc_walk_* */
} evch_subd_t;

/*
 * General purpose event channel descriptor structure. This is the main
 * structure for event subscribing, publishing, delivery to/from an event
 * channel.
 */
typedef struct {
	evch_dlelem_t	ch_link;	/* Must be first elem. of structure */
	char		*ch_name;	/* Channel name */
	size_t		ch_namelen;	/* Length of channel name buffer */
	kmutex_t	ch_mutex;	/* To protect this structure */
	evch_eventq_t	*ch_queue;	/* Publisher event queue */
	evch_dlist_t	ch_subscr;	/* List of subscr. data (evch_subd_t) */
	uint32_t	ch_bindings;	/* No of bindings to this channel */
	int		ch_maxbinds;	/* Maximum number of binds */
	uid_t		ch_uid;		/* Creators effective user id */
	gid_t		ch_gid;		/* Creators effective group id */
	kmutex_t	ch_pubmx;	/* Mutex for ch_pubcv and ch_nevents */
	kcondvar_t	ch_pubcv;	/* To set publisher to sleep */
	uint32_t	ch_nevents;	/* Current number of events */
	uint32_t	ch_maxev;	/* Maximum number of events */
	int		ch_maxsubscr;	/* Maximum number of subscriptions */
	int		ch_holdpend;	/* Hold pending events mode if != 0 */
	time_t		ch_ctime;	/* Channel creation time */
	nvlist_t	*ch_propnvl;	/* Channel properties nvlist */
	int64_t		ch_propnvlgen;	/* Properties generation number */
} evch_chan_t;

/*
 * Channel binding structure. Allocated per binding to a channel. Protected
 * by locking the channel structure
 */
typedef struct {
	evch_chan_t	*bd_channel;
	evch_subd_t	*bd_sublst;	/* chain of all subscriptions */
} evch_bind_t;

/*
 * Structure to keep a snapshot of all events of a channel
 */
typedef struct {
	evch_eventq_t	*sn_queue;	/* Event queue with snapshot of ev's */
	sysevent_impl_t	*sn_nxtev;	/* Pointer to find next event */
} evchanq_t;

/* Project private interfaces */
extern evchan_t *evch_usrchanopen(const char *name, uint32_t flags, int *err);
extern void evch_usrchanclose(evchan_t *cbp);
extern sysevent_impl_t *evch_usrallocev(size_t evsize, uint32_t flags);
extern void evch_usrfreeev(sysevent_impl_t *ev);
extern int evch_usrpostevent(evchan_t *bp, sysevent_impl_t *ev, uint32_t flags);
extern int evch_usrsubscribe(evchan_t *bp, const char *sid, const char *class,
    int d, uint32_t flags);
extern int evch_usrcontrol_set(evchan_t *bp, int cmd, uint32_t value);
extern int evch_usrcontrol_get(evchan_t *bp, int cmd, uint32_t *value);
extern void evch_usrunsubscribe(evchan_t *bp, const char *subid, uint32_t flag);
extern int evch_usrgetchnames(char *buf, size_t size);
extern int evch_usrgetchdata(char *chname, void *buf, size_t size);
extern void evch_usrsetpropnvl(evchan_t *bp, nvlist_t *nvl);
extern int evch_usrgetpropnvl(evchan_t *bp, nvlist_t **nvlp, int64_t *genp);

extern void sysevent_evc_init();
extern void sysevent_evc_thrinit();
extern evchanq_t *sysevent_evc_walk_init(evchan_t *, char *);
extern sysevent_t *sysevent_evc_walk_step(evchanq_t *);
extern void sysevent_evc_walk_fini(evchanq_t *);
extern char *sysevent_evc_event_attr(sysevent_t *, size_t *);

#endif /* _KERNEL */

/*
 * Structures and limits to deliver channel data to syseventadm
 */
#define	EVCH_MAX_DATA_SIZE	(1024 * 1024)

typedef struct {
	uint32_t	sb_nextoff;	/* Offset to next subscr info struct */
	uint32_t	sb_stroff;	/* Offset to strings */
	uint32_t	sb_clnamoff;	/* Offset of class in sb_strings */
	uint32_t	sb_pid;		/* Subscriber process id */
	uint32_t	sb_nevents;	/* Current no of event in sub q */
	uint32_t	sb_evhwm;	/* High watermark of sub q */
	uint32_t	sb_persist;	/* != 0 if subscription persists */
	uint32_t	sb_status;	/* != 0 if subscription is inactive */
	uint32_t	sb_active;	/* > 0 if subscription is in use */
	uint32_t	sb_dump;	/* != 0 if sub will be dumped */
	char		sb_strings[1];	/* String space for subid and class */
} sev_subinfo_t;

typedef struct {
	uint32_t	cd_version;	/* Version of this structure */
	uint32_t	cd_suboffs;	/* Offset of subscriber info struct */
	uint64_t	cd_ctime;	/* Creation time */
	uint32_t	cd_uid;		/* User id */
	uint32_t	cd_gid;		/* Owner group id */
	uint32_t	cd_perms;	/* Permission bits */
	uint32_t	cd_maxev;	/* Max number of events */
	uint32_t	cd_evhwm;	/* High watermark of main event queue */
	uint32_t	cd_nevents;	/* current no of events in main ev q */
	uint32_t	cd_maxsub;	/* Max number of subscriptions */
	uint32_t	cd_nsub;	/* Current number of subscriptions */
	uint32_t	cd_maxbinds;	/* Max number of binds */
	uint32_t	cd_nbinds;	/* Current number of binds */
	uint32_t	cd_holdpend;	/* != 0 when HOLDPEND mode is set */
	uint32_t	cd_limev;	/* Limit of events per channel */
	sev_subinfo_t	cd_subinfo[1];	/* Per subscriber data */
} sev_chinfo_t;

/*
 * Project private flags for sysevent_evc_subscribe. Bits 0 to 7 are reserved
 * for the consolidation private interface, so we must use bits 8-15 here.
 */
#define	EVCH_SUB_DUMP		(0x01 << 8)

/*
 * Permission flags
 */
#define	EVCH_PUB		0x0004	/* wants to publish events */
#define	EVCH_SUB		0x0008	/* wants to subscribe to channel */

#define	EVCH_SUBU		0x0001	/* Subscribing allowed for uid */
#define	EVCH_PUBU		0x0002	/* Publishing allowed for uid */
#define	EVCH_PSUSR		0x0003	/* EVCH_SUBU + EVCH_PUBU */
#define	EVCH_SUBG		0x0004	/* Subscribing allowed for gid */
#define	EVCH_PUBG		0x0008	/* Publishing allowed for gid */
#define	EVCH_PSGRP		0x000C	/* EVCH_SUBG + EVCH_PUBG */
#define	EVCH_SUBO		0x0010	/* Subscribing allowed to all users */
#define	EVCH_PUBO		0x0020	/* Publishing allowed to all users */
#define	EVCH_PSOTH		0x0030	/* EVCH_SUBO + EVCH_PUBO */
#define	EVCH_PSALL		0x003f	/* Mask of all permission bits */

/*
 * Sysevent driver ioctls
 */
#define	SEV_BASE		0x53455600
#define	SEV_PUBLISH		SEV_BASE | 0x01
#define	SEV_CHAN_OPEN		SEV_BASE | 0x02
#define	SEV_CHAN_CONTROL	SEV_BASE | 0x03
#define	SEV_SUBSCRIBE		SEV_BASE | 0x04
#define	SEV_UNSUBSCRIBE		SEV_BASE | 0x05
#define	SEV_CHANNAMES		SEV_BASE | 0x06
#define	SEV_CHANDATA		SEV_BASE | 0x07
#define	SEV_SETPROPNVL		SEV_BASE | 0x08
#define	SEV_GETPROPNVL		SEV_BASE | 0x09

#define	DEVSYSEVENT	"/dev/sysevent"
#define	DEVICESYSEVENT	"/devices/pseudo/sysevent@0:sysevent"

/*
 * Maximum allowed binding handles
 * It's a limit required by bitmap algorithm design (see sys/bitmap.h).
 * Use pack(4) to make sizeof structs be the same on x86 and amd64.
 */
#define	SYSEVENT_MINOR_MAX	SHRT_MAX

#if _LONG_LONG_ALIGNMENT == 8 && _LONG_LONG_ALIGNMENT_32 == 4
#pragma pack(4)
#endif

/* copyin/copyout data */
typedef struct box {
	uint64_t name;		/* pointer to something */
	uint32_t len;
} sev_box_t;

typedef struct bind_args {
	sev_box_t chan_name;
	uint32_t flags;
} sev_bind_args_t;

typedef struct control_args {
	uint32_t cmd;
	uint32_t value;
} sev_control_args_t;

typedef struct publish_args {
	sev_box_t ev;
	uint32_t flags;
} sev_publish_args_t;

typedef struct subscribe_args {
	sev_box_t sid;
	sev_box_t class_info;
	int door_desc;
	uint32_t flags;
} sev_subscribe_args_t;

typedef struct unsubscribe_args {
	sev_box_t sid;
} sev_unsubscribe_args_t;

typedef struct chandata {
	sev_box_t in_data;
	sev_box_t out_data;
} sev_chandata_args_t;

typedef struct propnvl_args {
	sev_box_t packednvl;	/* input and output */
	int64_t generation;	/* output on get operation */
} sev_propnvl_args_t;

#if _LONG_LONG_ALIGNMENT == 8 && _LONG_LONG_ALIGNMENT_32 == 4
#pragma pack()
#endif

#ifdef	__cplusplus
}
#endif

#endif	/* _SYS_SYSEVENT_IMPL_H */