4 * Implements LWKT messages and ports.
7 #ifndef _SYS_MSGPORT_H_
8 #define _SYS_MSGPORT_H_
11 #include <sys/queue.h> /* TAILQ_* macros */
13 #ifndef _SYS_STDINT_H_
14 #include <sys/stdint.h>
16 #ifndef _SYS_SPINLOCK_H_
17 #include <sys/spinlock.h>
22 #ifndef _SYS_MALLOC_H_
23 #include <sys/malloc.h>
30 struct lwkt_serialize;
33 typedef struct lwkt_msg *lwkt_msg_t;
34 typedef struct lwkt_port *lwkt_port_t;
36 typedef TAILQ_HEAD(lwkt_msg_queue, lwkt_msg) lwkt_msg_queue;
39 * The standard message and port structure for communications between
40 * threads. See kern/lwkt_msgport.c for documentation on how messages and
43 * A message may only be manipulated by whomever currently owns it,
44 * which generally means the originating port if the message has
45 * not been sent yet or has been replied, and the target port if the message
46 * has been sent and/or is undergoing processing.
48 * NOTE! 64-bit-align this structure.
50 typedef struct lwkt_msg {
51 TAILQ_ENTRY(lwkt_msg) ms_node; /* link node */
52 lwkt_port_t ms_target_port; /* current target or relay port */
53 lwkt_port_t ms_reply_port; /* async replies returned here */
54 void (*ms_abortfn)(struct lwkt_msg *);
55 int ms_flags; /* message flags */
56 int ms_error; /* positive error code or 0 */
58 void *ms_resultp; /* misc pointer data or result */
59 int ms_result; /* standard 'int'eger result */
60 long ms_lresult; /* long result */
61 int ms_fds[2]; /* two int bit results */
62 __int32_t ms_result32; /* 32 bit result */
63 __int64_t ms_result64; /* 64 bit result */
64 __off_t ms_offset; /* off_t result */
66 int ms_pad[2]; /* future use */
70 * Message state flags are manipulated by the current owner only.
72 * DONE Indicates completion of the reply. This flag is also set
73 * for unsent messages.
75 * REPLY Indicates message is being replied but may or may not
76 * have been queued or returned yet. This bit is left set
77 * when a message is retrieved from a reply port so the caller
78 * can distinguish between requests and replies.
80 * QUEUED Indicates message is queued on reply or target port, or
83 * SYNC Indicates that the originator is blocked directly on the
84 * message and that the message should be signaled on
85 * completion instead of queued.
87 * INTRANSIT Indicates that the message state is indeterminant (e.g.
88 * being passed through an IPI).
90 * ABORTABLE Static flag indicates that ms_abortfn is valid.
92 * High 16 bits are available to message handlers.
94 #define MSGF_DONE 0x0001 /* message is complete */
95 #define MSGF_REPLY 0x0002 /* asynch message has been returned */
96 #define MSGF_QUEUED 0x0004 /* message has been queued sanitychk */
97 #define MSGF_SYNC 0x0008 /* synchronous message operation */
98 #define MSGF_INTRANSIT 0x0010 /* in-transit (IPI) */
99 #define MSGF_WAITING 0x0020 /* MSGF_SYNC being waited upon */
100 #define MSGF_DROPABLE 0x0040 /* message supports drop */
101 #define MSGF_ABORTABLE 0x0080 /* message supports abort */
102 #define MSGF_PRIORITY 0x0100 /* priority message */
104 #define MSGF_USER0 0x00010000
105 #define MSGF_USER1 0x00020000
106 #define MSGF_USER2 0x00040000
107 #define MSGF_USER3 0x00080000
109 #define MSG_CMD_CDEV 0x00010000
110 #define MSG_CMD_VFS 0x00020000
111 #define MSG_CMD_SYSCALL 0x00030000
112 #define MSG_SUBCMD_MASK 0x0000FFFF
115 MALLOC_DECLARE(M_LWKTMSG);
119 * Notes on port processing requirements:
122 * - may return synchronous error code (error != EASYNC) directly and
123 * does not need to check or set MSGF_DONE if so, or set ms_target_port
124 * - for asynch procesing should clear MSGF_DONE and set ms_target_port
125 * to port prior to initiation of the command.
128 * - wait for a particular message to be returned.
131 * - wait for a new message on the specified port.
134 * - reply a message (executed on the originating port to return a
135 * message to it). This can be rather involved if abort is to be
136 * supported, see lwkt_default_replyport(). Generally speaking
137 * one sets MSGF_DONE and MSGF_REPLY. If MSGF_SYNC is set the message
138 * is not queued to the port and the reply code wakes up the waiter
142 * - drop a specific message from the specified port. Currently only
143 * threads' embedded ports (thread ports or spin ports) support this
144 * function and must be used in the port's owner thread.
145 * (returns 0 on success, ENOENT on error).
147 * The use of mpu_td and mp_u.spin is specific to the port callback function
148 * set. Default ports are tied to specific threads and use cpu locality
149 * of reference and mpu_td (and not mp_u.spin at all). Descriptor ports
150 * assume access via descriptors, signal interruption, etc. Such ports use
151 * mp_u.spin (and not mpu_td at all) and may be accessed by multiple threads.
153 * Threads' embedded ports always have mpu_td back pointing to themselves.
155 typedef struct lwkt_port {
156 lwkt_msg_queue mp_msgq;
157 lwkt_msg_queue mp_msgq_prio;
161 struct spinlock spin;
162 struct lwkt_serialize *serialize;
165 struct thread *mpu_td;
166 void * (*mp_getport)(lwkt_port_t);
167 int (*mp_putport)(lwkt_port_t, lwkt_msg_t);
168 int (*mp_waitmsg)(lwkt_msg_t, int flags);
169 void * (*mp_waitport)(lwkt_port_t, int flags);
170 void (*mp_replyport)(lwkt_port_t, lwkt_msg_t);
171 int (*mp_dropmsg)(lwkt_port_t, lwkt_msg_t);
172 int (*mp_putport_oncpu)(lwkt_port_t, lwkt_msg_t);
177 #define mpu_spin mp_u.spin
178 #define mpu_serialize mp_u.serialize
179 #define mpu_data mp_u.data
184 * WAITING The owner of the port is descheduled waiting for a message
185 * to be replied. In case this a spin port there can actually
186 * be more than one thread waiting on the port.
188 #define MSGPORTF_WAITING 0x0001
191 * These functions are good for userland as well as the kernel. The
192 * messaging function support for userland is provided by the kernel's
193 * kern/lwkt_msgport.c. The port functions are provided by userland.
196 void lwkt_initport_thread(lwkt_port_t, struct thread *);
197 void lwkt_initport_spin(lwkt_port_t, struct thread *, boolean_t);
198 void lwkt_initport_serialize(lwkt_port_t, struct lwkt_serialize *);
199 void lwkt_initport_panic(lwkt_port_t);
200 void lwkt_initport_replyonly_null(lwkt_port_t);
201 void lwkt_initport_replyonly(lwkt_port_t,
202 void (*rportfn)(lwkt_port_t, lwkt_msg_t));
203 void lwkt_initport_putonly(lwkt_port_t,
204 int (*pportfn)(lwkt_port_t, lwkt_msg_t));
206 void lwkt_sendmsg(lwkt_port_t, lwkt_msg_t);
207 void lwkt_sendmsg_oncpu(lwkt_port_t, lwkt_msg_t);
208 void lwkt_sendmsg_prepare(lwkt_port_t, lwkt_msg_t);
209 void lwkt_sendmsg_start(lwkt_port_t, lwkt_msg_t);
210 int lwkt_domsg(lwkt_port_t, lwkt_msg_t, int);
211 int lwkt_forwardmsg(lwkt_port_t, lwkt_msg_t);
212 void lwkt_abortmsg(lwkt_msg_t);