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_SPINLOCK_H_
14 #include <sys/spinlock.h>
16 #include <machine/stdint.h>
20 struct lwkt_serialize;
23 typedef struct lwkt_msg *lwkt_msg_t;
24 typedef struct lwkt_port *lwkt_port_t;
26 typedef TAILQ_HEAD(lwkt_msg_queue, lwkt_msg) lwkt_msg_queue;
29 * The standard message and port structure for communications between
30 * threads. See kern/lwkt_msgport.c for documentation on how messages and
33 * A message may only be manipulated by whomever currently owns it,
34 * which generally means the originating port if the message has
35 * not been sent yet or has been replied, and the target port if the message
36 * has been sent and/or is undergoing processing.
38 * NOTE! 64-bit-align this structure.
40 typedef struct lwkt_msg {
41 TAILQ_ENTRY(lwkt_msg) ms_node; /* link node */
42 lwkt_port_t ms_target_port; /* current target or relay port */
43 lwkt_port_t ms_reply_port; /* async replies returned here */
44 void (*ms_abortfn)(struct lwkt_msg *);
45 int ms_flags; /* message flags */
46 int ms_error; /* positive error code or 0 */
48 void *ms_resultp; /* misc pointer data or result */
49 int ms_result; /* standard 'int'eger result */
50 long ms_lresult; /* long result */
51 int ms_fds[2]; /* two int bit results */
52 __int32_t ms_result32; /* 32 bit result */
53 __int64_t ms_result64; /* 64 bit result */
54 __off_t ms_offset; /* off_t result */
56 void (*ms_receiptfn)(struct lwkt_msg *, lwkt_port_t);
60 * Message state flags are manipulated by the current owner only.
62 * DONE Indicates completion of the reply. This flag is also set
63 * for unsent messages.
65 * REPLY Indicates message is being replied but may or may not
66 * have been queued or returned yet. This bit is left set
67 * when a message is retrieved from a reply port so the caller
68 * can distinguish between requests and replies.
70 * QUEUED Indicates message is queued on reply or target port, or
73 * SYNC Indicates that the originator is blocked directly on the
74 * message and that the message should be signaled on
75 * completion instead of queued.
77 * INTRANSIT Indicates that the message state is indeterminant (e.g.
78 * being passed through an IPI).
80 * ABORTABLE Static flag indicates that ms_abortfn is valid.
82 * High 16 bits are available to message handlers.
84 #define MSGF_DONE 0x0001 /* message is complete */
85 #define MSGF_REPLY 0x0002 /* asynch message has been returned */
86 #define MSGF_QUEUED 0x0004 /* message has been queued sanitychk */
87 #define MSGF_SYNC 0x0008 /* synchronous message operation */
88 #define MSGF_INTRANSIT 0x0010 /* in-transit (IPI) */
89 #define MSGF_WAITING 0x0020 /* MSGF_SYNC being waited upon */
90 #define MSGF_DROPABLE 0x0040 /* message supports drop */
91 #define MSGF_ABORTABLE 0x0080 /* message supports abort */
92 #define MSGF_PRIORITY 0x0100 /* priority message */
93 #define MSGF_RECEIPT 0x0200 /* need receipt after put done */
95 #define MSGF_USER0 0x00010000
96 #define MSGF_USER1 0x00020000
97 #define MSGF_USER2 0x00040000
98 #define MSGF_USER3 0x00080000
100 #define MSG_CMD_CDEV 0x00010000
101 #define MSG_CMD_VFS 0x00020000
102 #define MSG_CMD_SYSCALL 0x00030000
103 #define MSG_SUBCMD_MASK 0x0000FFFF
106 * Notes on port processing requirements:
109 * - may return synchronous error code (error != EASYNC) directly and
110 * does not need to check or set MSGF_DONE if so, or set ms_target_port
111 * - for asynch procesing should clear MSGF_DONE and set ms_target_port
112 * to port prior to initiation of the command.
115 * - wait for a particular message to be returned.
118 * - wait for a new message on the specified port.
121 * - reply a message (executed on the originating port to return a
122 * message to it). This can be rather involved if abort is to be
123 * supported, see lwkt_default_replyport(). Generally speaking
124 * one sets MSGF_DONE and MSGF_REPLY. If MSGF_SYNC is set the message
125 * is not queued to the port and the reply code wakes up the waiter
129 * - drop a specific message from the specified port. Currently only
130 * threads' embedded ports (thread ports or spin ports) support this
131 * function and must be used in the port's owner thread.
132 * (returns 0 on success, ENOENT on error).
134 * The use of mpu_td and mp_u.spin is specific to the port callback function
135 * set. Default ports are tied to specific threads and use cpu locality
136 * of reference and mpu_td (and not mp_u.spin at all). Descriptor ports
137 * assume access via descriptors, signal interruption, etc. Such ports use
138 * mp_u.spin (and not mpu_td at all) and may be accessed by multiple threads.
140 * Threads' embedded ports always have mpu_td back pointing to themselves.
142 typedef struct lwkt_port {
143 lwkt_msg_queue mp_msgq;
144 lwkt_msg_queue mp_msgq_prio;
148 struct spinlock spin;
149 struct lwkt_serialize *serialize;
152 struct thread *mpu_td;
153 void * (*mp_getport)(lwkt_port_t);
154 int (*mp_putport)(lwkt_port_t, lwkt_msg_t);
155 int (*mp_waitmsg)(lwkt_msg_t, int flags);
156 void * (*mp_waitport)(lwkt_port_t, int flags);
157 void (*mp_replyport)(lwkt_port_t, lwkt_msg_t);
158 int (*mp_dropmsg)(lwkt_port_t, lwkt_msg_t);
159 int (*mp_putport_oncpu)(lwkt_port_t, lwkt_msg_t);
164 #include <sys/types.h> /* for boolean_t */
166 #define mpu_spin mp_u.spin
167 #define mpu_serialize mp_u.serialize
168 #define mpu_data mp_u.data
173 * WAITING The owner of the port is descheduled waiting for a message
174 * to be replied. In case this a spin port there can actually
175 * be more than one thread waiting on the port.
177 #define MSGPORTF_WAITING 0x0001
180 * These functions are good for userland as well as the kernel. The
181 * messaging function support for userland is provided by the kernel's
182 * kern/lwkt_msgport.c. The port functions are provided by userland.
185 void lwkt_initport_thread(lwkt_port_t, struct thread *);
186 void lwkt_initport_spin(lwkt_port_t, struct thread *, boolean_t);
187 void lwkt_initport_serialize(lwkt_port_t, struct lwkt_serialize *);
188 void lwkt_initport_panic(lwkt_port_t);
189 void lwkt_initport_replyonly_null(lwkt_port_t);
190 void lwkt_initport_replyonly(lwkt_port_t,
191 void (*rportfn)(lwkt_port_t, lwkt_msg_t));
192 void lwkt_initport_putonly(lwkt_port_t,
193 int (*pportfn)(lwkt_port_t, lwkt_msg_t));
195 void lwkt_sendmsg(lwkt_port_t, lwkt_msg_t);
196 void lwkt_sendmsg_oncpu(lwkt_port_t, lwkt_msg_t);
197 void lwkt_sendmsg_prepare(lwkt_port_t, lwkt_msg_t);
198 void lwkt_sendmsg_start(lwkt_port_t, lwkt_msg_t);
199 void lwkt_sendmsg_start_oncpu(lwkt_port_t, lwkt_msg_t);
200 int lwkt_domsg(lwkt_port_t, lwkt_msg_t, int);
201 int lwkt_forwardmsg(lwkt_port_t, lwkt_msg_t);
202 void lwkt_abortmsg(lwkt_msg_t);