port_vnops.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (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 2004 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#include <sys/types.h>
#include <sys/vnode.h>
#include <sys/kmem.h>
#include <fs/fs_subr.h>
#include <sys/proc.h>
#include <sys/kstat.h>
#include <sys/port_impl.h>
/* local functions */
static int port_open(struct vnode **, int, cred_t *);
static int port_close(struct vnode *, int, int, offset_t, cred_t *);
static int port_getattr(struct vnode *, struct vattr *, int, cred_t *);
static int port_access(struct vnode *, int, int, cred_t *);
static int port_realvp(vnode_t *, vnode_t **);
static int port_poll(vnode_t *, short, int, short *, struct pollhead **);
static void port_inactive(struct vnode *, cred_t *);
const fs_operation_def_t port_vnodeops_template[] = {
VOPNAME_OPEN, port_open,
VOPNAME_CLOSE, port_close,
VOPNAME_GETATTR, port_getattr,
VOPNAME_ACCESS, port_access,
VOPNAME_INACTIVE, (fs_generic_func_p) port_inactive,
VOPNAME_FRLOCK, fs_error,
VOPNAME_REALVP, port_realvp,
VOPNAME_POLL, (fs_generic_func_p) port_poll,
VOPNAME_PATHCONF, fs_error,
VOPNAME_DISPOSE, fs_error,
VOPNAME_GETSECATTR, fs_error,
VOPNAME_SHRLOCK, fs_error,
NULL, NULL
};
/* ARGSUSED */
static int
port_open(struct vnode **vpp, int flag, cred_t *cr)
{
return (0);
}
/*
* port_discard_events() scans the port event queue for events owned
* by current proc. Non-shareable events will be discarded, all other
* events remain in the event queue.
*/
void
port_discard_events(port_queue_t *portq)
{
port_kevent_t *kevp;
pid_t pid = curproc->p_pid;
/*
* Both mutexes are required to avoid interaction with other threads
* in port_get(n).
*/
mutex_enter(&portq->portq_mutex);
mutex_enter(&portq->portq_block_mutex);
port_push_eventq(portq); /* empty temporary queue */
kevp = list_head(&portq->portq_list);
while (kevp) {
if (kevp->portkev_pid == pid) {
/* own event, check if it is shareable */
if (kevp->portkev_flags & PORT_KEV_NOSHARE)
kevp->portkev_flags |= PORT_KEV_FREE;
}
kevp = list_next(&portq->portq_list, kevp);
}
mutex_exit(&portq->portq_block_mutex);
mutex_exit(&portq->portq_mutex);
}
/*
* Called from port_close().
* Free all kernel events structures which are still in the event queue.
*/
static void
port_close_events(port_queue_t *portq)
{
port_kevent_t *pkevp;
int events; /* ignore events */
mutex_enter(&portq->portq_mutex);
while (pkevp = list_head(&portq->portq_list)) {
portq->portq_nent--;
list_remove(&portq->portq_list, pkevp);
if (pkevp->portkev_callback) {
(void) (*pkevp->portkev_callback)(pkevp->portkev_arg,
&events, pkevp->portkev_pid, PORT_CALLBACK_CLOSE,
pkevp);
}
mutex_exit(&portq->portq_mutex);
port_free_event_local(pkevp, 0);
mutex_enter(&portq->portq_mutex);
}
mutex_exit(&portq->portq_mutex);
}
/*
* The port_close() function is called from standard close(2) when
* the file descriptor is of type S_IFPORT/VPORT.
* Port file descriptors behave like standard file descriptors. It means,
* the port file/vnode is only destroyed on last close.
* If the reference counter is > 1 then
* - sources associated with the port will be notified about the close,
* - objects associated with the port will be dissociated,
* - pending and delivered events will be discarded.
* On last close all references and caches will be removed. The vnode itself
* will be destroyed with VOP_RELE().
*/
/* ARGSUSED */
static int
port_close(struct vnode *vp, int flag, int count, offset_t offset, cred_t *cr)
{
port_t *pp;
port_queue_t *portq;
port_source_t *ps;
port_source_t *ps_next;
int source;
pp = VTOEP(vp);
mutex_enter(&pp->port_mutex);
if (pp->port_flags & PORT_CLOSED) {
mutex_exit(&pp->port_mutex);
return (0);
}
mutex_exit(&pp->port_mutex);
portq = &pp->port_queue;
if (count > 1) {
/*
* It is not the last close.
* Remove/free all event resources owned by the current proc
* First notify all with the port associated sources about the
* close(2). The last argument of the close callback function
* advises the source about the type of of the close.
* If the port was set in alert mode by the curren process then
* remove the alert mode.
*/
/* check alert mode of the port */
mutex_enter(&portq->portq_mutex);
if ((portq->portq_flags & PORTQ_ALERT) &&
(portq->portq_alert.portal_pid == curproc->p_pid))
portq->portq_flags &= ~PORTQ_ALERT;
mutex_exit(&portq->portq_mutex);
/* notify all event sources about port_close() */
mutex_enter(&portq->portq_source_mutex);
for (source = 0; source < PORT_SCACHE_SIZE; source++) {
ps = portq->portq_scache[PORT_SHASH(source)];
for (; ps != NULL; ps = ps->portsrc_next) {
if (ps->portsrc_close != NULL)
(*ps->portsrc_close)
(ps->portsrc_closearg, pp->port_fd,
curproc->p_pid, 0);
}
}
mutex_exit(&portq->portq_source_mutex);
port_discard_events(&pp->port_queue);
return (0);
}
/*
* We are executing the last close of the port -> discard everything
* Make sure that all threads/processes accessing this port leave
* the kernel immediately.
*/
mutex_enter(&portq->portq_mutex);
portq->portq_flags |= PORTQ_CLOSE;
while (portq->portq_thrcnt > 0) {
if (portq->portq_thread != NULL)
cv_signal(&portq->portq_thread->portget_cv);
cv_wait(&portq->portq_closecv, &portq->portq_mutex);
}
mutex_exit(&portq->portq_mutex);
/*
* Send "last close" message to associated sources.
* - new event allocation requests are being denied since uf_file entry
* was set to NULL in closeandsetf().
* - all still allocated event structures must be returned to the
* port immediately:
* - call port_free_event(*event) or
* - call port_send_event(*event) to complete event operations
* which need activities in a dedicated process environment.
* The port_close() function waits until all allocated event structures
* are delivered back to the port.
*/
mutex_enter(&portq->portq_source_mutex);
for (source = 0; source < PORT_SCACHE_SIZE; source++) {
ps = portq->portq_scache[PORT_SHASH(source)];
for (; ps != NULL; ps = ps_next) {
ps_next = ps->portsrc_next;
if (ps->portsrc_close != NULL)
(*ps->portsrc_close)(ps->portsrc_closearg,
pp->port_fd, curproc->p_pid, 1);
kmem_free(ps, sizeof (port_source_t));
}
}
kmem_free(portq->portq_scache,
PORT_SCACHE_SIZE * sizeof (port_source_t *));
portq->portq_scache = NULL;
mutex_exit(&portq->portq_source_mutex);
mutex_enter(&portq->portq_mutex);
/* Wait for outstanding events */
while (pp->port_curr > portq->portq_nent)
cv_wait(&portq->portq_closecv, &portq->portq_mutex);
mutex_exit(&portq->portq_mutex);
/*
* If PORT_SOURCE_FD objects were not associated with the port then
* it is necessary to free the port_fdcache structure here.
*/
if (portq->portq_pcp != NULL) {
mutex_destroy(&portq->portq_pcp->pc_lock);
kmem_free(portq->portq_pcp, sizeof (port_fdcache_t));
portq->portq_pcp = NULL;
}
/*
* Now all events are passed back to the port,
* discard remaining events in the port queue
*/
port_close_events(portq);
return (0);
}
/*
* The port_poll() function is the VOP_POLL() entry of event ports.
* Event ports return:
* POLLIN : events are available in the event queue
* POLLOUT : event queue can still accept events
*/
/*ARGSUSED*/
static int
port_poll(vnode_t *vp, short events, int anyyet, short *reventsp,
struct pollhead **phpp)
{
port_t *pp;
port_queue_t *portq;
short levents;
pp = VTOEP(vp);
portq = &pp->port_queue;
levents = 0;
mutex_enter(&portq->portq_mutex);
if (portq->portq_nent)
levents = POLLIN;
if (pp->port_curr < pp->port_max_events)
levents |= POLLOUT;
levents &= events;
*reventsp = levents;
if (levents == 0) {
if (!anyyet) {
*phpp = &pp->port_pollhd;
portq->portq_flags |=
events & POLLIN ? PORTQ_POLLIN : 0;
portq->portq_flags |=
events & POLLOUT ? PORTQ_POLLOUT : 0;
}
}
mutex_exit(&portq->portq_mutex);
return (0);
}
/* ARGSUSED */
static int
port_getattr(struct vnode *vp, struct vattr *vap, int flags, cred_t *cr)
{
port_t *pp;
extern dev_t portdev;
pp = VTOEP(vp);
vap->va_mask = 0; /* bit-mask of attributes */
vap->va_type = vp->v_type; /* vnode type (for create) */
vap->va_mode = 0; /* file access mode */
vap->va_uid = pp->port_uid; /* owner user id */
vap->va_gid = pp->port_gid; /* owner group id */
vap->va_fsid = portdev; /* file system id */
vap->va_nodeid = (ino64_t)0; /* node id */
vap->va_nlink = vp->v_count; /* number of references to file */
vap->va_size = (u_offset_t)pp->port_queue.portq_nent; /* file size */
vap->va_atime = pp->port_ctime; /* time of last access */
vap->va_mtime = pp->port_ctime; /* time of last modification */
vap->va_ctime = pp->port_ctime; /* time file ``created'' */
vap->va_rdev = portdev; /* device the file represents */
vap->va_blksize = 0; /* fundamental block size */
vap->va_nblocks = (fsblkcnt64_t)0; /* # of blocks allocated */
vap->va_seq = 0; /* sequence number */
return (0);
}
/*
* Destroy the port.
*/
/* ARGSUSED */
static void
port_inactive(struct vnode *vp, cred_t *cr)
{
port_t *pp = VTOEP(vp);
extern port_kstat_t port_kstat;
mutex_enter(&port_control.pc_mutex);
port_control.pc_nents--;
curproc->p_portcnt--;
port_kstat.pks_ports.value.ui32--;
mutex_exit(&port_control.pc_mutex);
vn_free(vp);
mutex_destroy(&pp->port_mutex);
mutex_destroy(&pp->port_queue.portq_mutex);
mutex_destroy(&pp->port_queue.portq_source_mutex);
kmem_free(pp, sizeof (port_t));
}
/* ARGSUSED */
static int
port_access(struct vnode *vp, int mode, int flags, cred_t *cr)
{
return (0);
}
/* ARGSUSED */
static int
port_realvp(vnode_t *vp, vnode_t **vpp)
{
*vpp = vp;
return (0);
}