diff --git a/share/man/man9/g_event.9 b/share/man/man9/g_event.9 index 0bdd0ab6688b..32c4703100d8 100644 --- a/share/man/man9/g_event.9 +++ b/share/man/man9/g_event.9 @@ -1,189 +1,219 @@ .\" .\" Copyright (c) 2004 Pawel Jakub Dawidek .\" All rights reserved. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR .\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES .\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. .\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT, .\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT .\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, .\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY .\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. .\" .\" $FreeBSD$ .\" -.Dd January 16, 2004 +.Dd July 23, 2021 .Dt G_EVENT 9 .Os .Sh NAME .Nm g_post_event , .Nm g_waitfor_event , .Nm g_cancel_event .Nd "GEOM events management" .Sh SYNOPSIS .In geom/geom.h .Ft int .Fn g_post_event "g_event_t *func" "void *arg" "int flag" ... .Ft int .Fn g_waitfor_event "g_event_t *func" "void *arg" "int flag" ... .Ft void .Fn g_cancel_event "void *ref" +.Ft "struct g_event *" +.Fn g_alloc_event "int flag" +.Ft void +.Fn g_post_event_ep "g_event_t *func" "void *arg" "struct g_event *ep" ... .Sh DESCRIPTION The GEOM framework has its own event queue to inform classes about important events. The event queue can be also used by GEOM classes themselves, for example to work around some restrictions in the I/O path, where sleeping, heavy weight tasks, etc.\& are not permitted. .Pp The .Fn g_post_event function tells the GEOM framework to call function .Fa func with argument .Fa arg from the event queue. The .Fa flag argument is passed to .Xr malloc 9 for memory allocations inside of .Fn g_post_event . The only allowed flags are .Dv M_WAITOK and .Dv M_NOWAIT . The rest of the arguments are used as references to identify the event. An event can be canceled by using any of the given references as an argument to .Fn g_cancel_event . The list of references has to end with a .Dv NULL value. .Pp The .Fn g_waitfor_event function is a blocking version of the .Fn g_post_event function. It waits until the event is finished or canceled and then returns. .Pp The +.Fn g_post_event_ep +function posts the event with a pre-allocated +.Va struct g_event . +An event may be pre-allocated with +.Fn g_alloc_event . +.Pp +The .Fn g_cancel_event function cancels all event(s) identified by .Fa ref . Cancellation is equivalent to calling the requested function with requested arguments and argument .Fa flag set to .Dv EV_CANCEL . .Sh RESTRICTIONS/CONDITIONS .Fn g_post_event : .Bl -item -offset indent .It The argument .Fa flag has to be .Dv M_WAITOK or .Dv M_NOWAIT . .It The list of references has to end with a .Dv NULL value. .El .Pp .Fn g_waitfor_event : .Bl -item -offset indent .It The argument .Fa flag has to be .Dv M_WAITOK or .Dv M_NOWAIT . .It The list of references has to end with a .Dv NULL value. .It The .Fn g_waitfor_event function cannot be called from an event, since doing so would result in a deadlock. .El +.Pp +.Fn g_alloc_event : +.Bl -item -offset indent +.It +The argument +.Fa flag +has to be +.Dv M_WAITOK +or +.Dv M_NOWAIT . +.It +The returned +.Va struct g_event * +must be freed with +.Fn g_free +if +.Fn g_post_event_ep +is not called. +.El .Sh RETURN VALUES The .Fn g_post_event and .Fn g_waitfor_event functions return 0 if successful; otherwise an error code is returned. .Sh EXAMPLES Example of a function called from the event queue. .Bd -literal -offset indent void example_event(void *arg, int flag) { if (flag == EV_CANCEL) { printf("Event with argument %p canceled.\\n", arg); return; } printf("Event with argument %p called.\\n", arg); } .Ed .Sh ERRORS Possible errors for the .Fn g_post_event function: .Bl -tag -width Er .It Bq Er ENOMEM The .Fa flag argument was set to .Dv M_NOWAIT and there was insufficient memory. .El .Pp Possible errors for the .Fn g_waitfor_event function: .Bl -tag -width Er .It Bq Er EAGAIN The event was canceled. .It Bq Er ENOMEM The .Fa flag argument was set to .Dv M_NOWAIT and there was insufficient memory. .El .Sh SEE ALSO .Xr geom 4 , .Xr DECLARE_GEOM_CLASS 9 , .Xr g_access 9 , .Xr g_attach 9 , .Xr g_bio 9 , .Xr g_consumer 9 , .Xr g_data 9 , .Xr g_geom 9 , .Xr g_provider 9 , .Xr g_provider_by_name 9 , .Xr g_wither_geom 9 .Sh AUTHORS .An -nosplit This manual page was written by .An Pawel Jakub Dawidek Aq Mt pjd@FreeBSD.org . diff --git a/sys/geom/geom.h b/sys/geom/geom.h index cb294e2c7451..1aba1f46d6d5 100644 --- a/sys/geom/geom.h +++ b/sys/geom/geom.h @@ -1,441 +1,444 @@ /*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 2002 Poul-Henning Kamp * Copyright (c) 2002 Networks Associates Technology, Inc. * All rights reserved. * * This software was developed for the FreeBSD Project by Poul-Henning Kamp * and NAI Labs, the Security Research Division of Network Associates, Inc. * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the * DARPA CHATS research program. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. The names of the authors may not be used to endorse or promote * products derived from this software without specific prior written * permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * $FreeBSD$ */ #ifndef _GEOM_GEOM_H_ #define _GEOM_GEOM_H_ #include #include #include #include #include #include #include struct g_class; struct g_geom; struct g_consumer; struct g_provider; struct g_stat; struct thread; struct bio; struct sbuf; struct gctl_req; struct g_configargs; struct disk_zone_args; typedef int g_config_t (struct g_configargs *ca); typedef void g_ctl_req_t (struct gctl_req *, struct g_class *cp, char const *verb); typedef int g_ctl_create_geom_t (struct gctl_req *, struct g_class *cp, struct g_provider *pp); typedef int g_ctl_destroy_geom_t (struct gctl_req *, struct g_class *cp, struct g_geom *gp); typedef int g_ctl_config_geom_t (struct gctl_req *, struct g_geom *gp, const char *verb); typedef void g_init_t (struct g_class *mp); typedef void g_fini_t (struct g_class *mp); typedef struct g_geom * g_taste_t (struct g_class *, struct g_provider *, int flags); typedef int g_ioctl_t(struct g_provider *pp, u_long cmd, void *data, int fflag, struct thread *td); #define G_TF_NORMAL 0 #define G_TF_INSIST 1 #define G_TF_TRANSPARENT 2 typedef int g_access_t (struct g_provider *, int, int, int); /* XXX: not sure about the thread arg */ typedef void g_orphan_t (struct g_consumer *); typedef void g_start_t (struct bio *); typedef void g_spoiled_t (struct g_consumer *); typedef void g_attrchanged_t (struct g_consumer *, const char *attr); typedef void g_provgone_t (struct g_provider *); typedef void g_dumpconf_t (struct sbuf *, const char *indent, struct g_geom *, struct g_consumer *, struct g_provider *); typedef void g_resize_t(struct g_consumer *cp); /* * The g_class structure describes a transformation class. In other words * all BSD disklabel handlers share one g_class, all MBR handlers share * one common g_class and so on. * Certain operations are instantiated on the class, most notably the * taste and config_geom functions. */ struct g_class { const char *name; u_int version; u_int spare0; g_taste_t *taste; g_config_t *config; g_ctl_req_t *ctlreq; g_init_t *init; g_fini_t *fini; g_ctl_destroy_geom_t *destroy_geom; /* * Default values for geom methods */ g_start_t *start; g_spoiled_t *spoiled; g_attrchanged_t *attrchanged; g_dumpconf_t *dumpconf; g_access_t *access; g_orphan_t *orphan; g_ioctl_t *ioctl; g_provgone_t *providergone; g_resize_t *resize; void *spare1; void *spare2; /* * The remaining elements are private */ LIST_ENTRY(g_class) class; LIST_HEAD(,g_geom) geom; }; #define G_VERSION_00 0x19950323 #define G_VERSION_01 0x20041207 /* add fflag to g_ioctl_t */ #define G_VERSION G_VERSION_01 /* * The g_geom is an instance of a g_class. */ struct g_geom { char *name; struct g_class *class; LIST_ENTRY(g_geom) geom; LIST_HEAD(,g_consumer) consumer; LIST_HEAD(,g_provider) provider; TAILQ_ENTRY(g_geom) geoms; /* XXX: better name */ int rank; g_start_t *start; g_spoiled_t *spoiled; g_attrchanged_t *attrchanged; g_dumpconf_t *dumpconf; g_access_t *access; g_orphan_t *orphan; g_ioctl_t *ioctl; g_provgone_t *providergone; g_resize_t *resize; void *spare0; void *spare1; void *softc; unsigned flags; #define G_GEOM_WITHER 0x01 #define G_GEOM_VOLATILE_BIO 0x02 #define G_GEOM_IN_ACCESS 0x04 #define G_GEOM_ACCESS_WAIT 0x08 }; /* * The g_bioq is a queue of struct bio's. * XXX: possibly collection point for statistics. * XXX: should (possibly) be collapsed with sys/bio.h::bio_queue_head. */ struct g_bioq { TAILQ_HEAD(, bio) bio_queue; struct mtx bio_queue_lock; int bio_queue_length; }; /* * A g_consumer is an attachment point for a g_provider. One g_consumer * can only be attached to one g_provider, but multiple g_consumers * can be attached to one g_provider. */ struct g_consumer { struct g_geom *geom; LIST_ENTRY(g_consumer) consumer; struct g_provider *provider; LIST_ENTRY(g_consumer) consumers; /* XXX: better name */ int acr, acw, ace; int flags; #define G_CF_SPOILED 0x1 #define G_CF_ORPHAN 0x4 #define G_CF_DIRECT_SEND 0x10 #define G_CF_DIRECT_RECEIVE 0x20 struct devstat *stat; u_int nstart, nend; /* Two fields for the implementing class to use */ void *private; u_int index; }; /* * The g_geom_alias is a list node for aliases for the provider name for device * node creation. */ struct g_geom_alias { LIST_ENTRY(g_geom_alias) ga_next; const char *ga_alias; }; /* * A g_provider is a "logical disk". */ struct g_provider { char *name; LIST_ENTRY(g_provider) provider; struct g_geom *geom; LIST_HEAD(,g_consumer) consumers; int acr, acw, ace; int error; TAILQ_ENTRY(g_provider) orphan; off_t mediasize; u_int sectorsize; off_t stripesize; off_t stripeoffset; struct devstat *stat; u_int spare1; u_int spare2; u_int flags; #define G_PF_WITHER 0x2 #define G_PF_ORPHAN 0x4 #define G_PF_ACCEPT_UNMAPPED 0x8 #define G_PF_DIRECT_SEND 0x10 #define G_PF_DIRECT_RECEIVE 0x20 LIST_HEAD(,g_geom_alias) aliases; /* Two fields for the implementing class to use */ void *private; u_int index; }; /* BIO_GETATTR("GEOM::setstate") argument values. */ #define G_STATE_FAILED 0 #define G_STATE_REBUILD 1 #define G_STATE_RESYNC 2 #define G_STATE_ACTIVE 3 /* geom_dev.c */ struct cdev; void g_dev_print(void); void g_dev_physpath_changed(void); struct g_provider *g_dev_getprovider(struct cdev *dev); /* geom_dump.c */ void (g_trace)(int level, const char *, ...) __printflike(2, 3); #define G_T_TOPOLOGY 0x01 #define G_T_BIO 0x02 #define G_T_ACCESS 0x04 extern int g_debugflags; #define G_F_FOOTSHOOTING 0x10 #define G_F_DISKIOCTL 0x40 #define G_F_CTLDUMP 0x80 #define g_trace(level, fmt, ...) do { \ if (__predict_false(g_debugflags & (level))) \ (g_trace)(level, fmt, ## __VA_ARGS__); \ } while (0) /* geom_event.c */ typedef void g_event_t(void *, int flag); +struct g_event; #define EV_CANCEL 1 int g_post_event(g_event_t *func, void *arg, int flag, ...); int g_waitfor_event(g_event_t *func, void *arg, int flag, ...); void g_cancel_event(void *ref); int g_attr_changed(struct g_provider *pp, const char *attr, int flag); int g_media_changed(struct g_provider *pp, int flag); int g_media_gone(struct g_provider *pp, int flag); void g_orphan_provider(struct g_provider *pp, int error); void g_waitidlelock(void); +struct g_event *g_alloc_event(int flag); +void g_post_event_ep(g_event_t *func, void *arg, struct g_event *ep, ...); /* geom_subr.c */ int g_access(struct g_consumer *cp, int nread, int nwrite, int nexcl); int g_attach(struct g_consumer *cp, struct g_provider *pp); int g_compare_names(const char *namea, const char *nameb); void g_destroy_consumer(struct g_consumer *cp); void g_destroy_geom(struct g_geom *pp); void g_destroy_provider(struct g_provider *pp); void g_detach(struct g_consumer *cp); void g_error_provider(struct g_provider *pp, int error); struct g_provider *g_provider_by_name(char const *arg); int g_getattr__(const char *attr, struct g_consumer *cp, void *var, int len); #define g_getattr(a, c, v) g_getattr__((a), (c), (v), sizeof *(v)) int g_handleattr(struct bio *bp, const char *attribute, const void *val, int len); int g_handleattr_int(struct bio *bp, const char *attribute, int val); int g_handleattr_off_t(struct bio *bp, const char *attribute, off_t val); int g_handleattr_uint16_t(struct bio *bp, const char *attribute, uint16_t val); int g_handleattr_str(struct bio *bp, const char *attribute, const char *str); struct g_consumer * g_new_consumer(struct g_geom *gp); struct g_geom * g_new_geomf(struct g_class *mp, const char *fmt, ...) __printflike(2, 3); struct g_provider * g_new_providerf(struct g_geom *gp, const char *fmt, ...) __printflike(2, 3); void g_provider_add_alias(struct g_provider *pp, const char *fmt, ...) __printflike(2, 3); void g_resize_provider(struct g_provider *pp, off_t size); int g_retaste(struct g_class *mp); void g_spoil(struct g_provider *pp, struct g_consumer *cp); int g_std_access(struct g_provider *pp, int dr, int dw, int de); void g_std_done(struct bio *bp); void g_std_spoiled(struct g_consumer *cp); void g_wither_geom(struct g_geom *gp, int error); void g_wither_geom_close(struct g_geom *gp, int error); void g_wither_provider(struct g_provider *pp, int error); #if defined(DIAGNOSTIC) || defined(DDB) int g_valid_obj(void const *ptr); #endif #ifdef DIAGNOSTIC #define G_VALID_CLASS(foo) \ KASSERT(g_valid_obj(foo) == 1, ("%p is not a g_class", foo)) #define G_VALID_GEOM(foo) \ KASSERT(g_valid_obj(foo) == 2, ("%p is not a g_geom", foo)) #define G_VALID_CONSUMER(foo) \ KASSERT(g_valid_obj(foo) == 3, ("%p is not a g_consumer", foo)) #define G_VALID_PROVIDER(foo) \ KASSERT(g_valid_obj(foo) == 4, ("%p is not a g_provider", foo)) #else #define G_VALID_CLASS(foo) do { } while (0) #define G_VALID_GEOM(foo) do { } while (0) #define G_VALID_CONSUMER(foo) do { } while (0) #define G_VALID_PROVIDER(foo) do { } while (0) #endif int g_modevent(module_t, int, void *); /* geom_io.c */ struct bio * g_clone_bio(struct bio *); struct bio * g_duplicate_bio(struct bio *); void g_destroy_bio(struct bio *); void g_io_deliver(struct bio *bp, int error); int g_io_getattr(const char *attr, struct g_consumer *cp, int *len, void *ptr); int g_io_zonecmd(struct disk_zone_args *zone_args, struct g_consumer *cp); int g_io_flush(struct g_consumer *cp); int g_io_speedup(off_t shortage, u_int flags, size_t *resid, struct g_consumer *cp); void g_io_request(struct bio *bp, struct g_consumer *cp); struct bio *g_new_bio(void); struct bio *g_alloc_bio(void); void g_reset_bio(struct bio *); void * g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error); int g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length); int g_delete_data(struct g_consumer *cp, off_t offset, off_t length); void g_format_bio(struct sbuf *, const struct bio *bp); void g_print_bio(const char *prefix, const struct bio *bp, const char *fmtsuffix, ...) __printflike(3, 4); int g_use_g_read_data(void *, off_t, void **, int); int g_use_g_write_data(void *, off_t, void *, int); /* geom_kern.c / geom_kernsim.c */ #ifdef _KERNEL extern struct sx topology_lock; struct g_kerneldump { off_t offset; off_t length; struct dumperinfo di; }; MALLOC_DECLARE(M_GEOM); static __inline void * g_malloc(int size, int flags) { void *p; p = malloc(size, M_GEOM, flags); return (p); } static __inline void g_free(void *ptr) { #ifdef DIAGNOSTIC if (sx_xlocked(&topology_lock)) { KASSERT(g_valid_obj(ptr) == 0, ("g_free(%p) of live object, type %d", ptr, g_valid_obj(ptr))); } #endif free(ptr, M_GEOM); } #define g_topology_lock() \ do { \ sx_xlock(&topology_lock); \ } while (0) #define g_topology_try_lock() sx_try_xlock(&topology_lock) #define g_topology_unlock() \ do { \ sx_xunlock(&topology_lock); \ } while (0) #define g_topology_locked() sx_xlocked(&topology_lock) #define g_topology_assert() \ do { \ sx_assert(&topology_lock, SX_XLOCKED); \ } while (0) #define g_topology_assert_not() \ do { \ sx_assert(&topology_lock, SX_UNLOCKED); \ } while (0) #define g_topology_sleep(chan, timo) \ sx_sleep(chan, &topology_lock, 0, "gtopol", timo) #define DECLARE_GEOM_CLASS(class, name) \ static moduledata_t name##_mod = { \ #name, g_modevent, &class \ }; \ DECLARE_MODULE(name, name##_mod, SI_SUB_DRIVERS, SI_ORDER_SECOND); int g_is_geom_thread(struct thread *td); #ifndef _PATH_DEV #define _PATH_DEV "/dev/" #endif #endif /* _KERNEL */ /* geom_ctl.c */ int gctl_set_param(struct gctl_req *req, const char *param, void const *ptr, int len); void gctl_set_param_err(struct gctl_req *req, const char *param, void const *ptr, int len); void *gctl_get_param(struct gctl_req *req, const char *param, int *len); char const *gctl_get_asciiparam(struct gctl_req *req, const char *param); void *gctl_get_paraml(struct gctl_req *req, const char *param, int len); void *gctl_get_paraml_opt(struct gctl_req *req, const char *param, int len); int gctl_error(struct gctl_req *req, const char *fmt, ...) __printflike(2, 3); struct g_class *gctl_get_class(struct gctl_req *req, char const *arg); struct g_geom *gctl_get_geom(struct gctl_req *req, struct g_class *mp, char const *arg); struct g_provider *gctl_get_provider(struct gctl_req *req, char const *arg); #endif /* _GEOM_GEOM_H_ */ diff --git a/sys/geom/geom_event.c b/sys/geom/geom_event.c index b829d2ef637c..f9a1d445d36a 100644 --- a/sys/geom/geom_event.c +++ b/sys/geom/geom_event.c @@ -1,446 +1,474 @@ /*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 2002 Poul-Henning Kamp * Copyright (c) 2002 Networks Associates Technology, Inc. * All rights reserved. * * This software was developed for the FreeBSD Project by Poul-Henning Kamp * and NAI Labs, the Security Research Division of Network Associates, Inc. * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the * DARPA CHATS research program. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. The names of the authors may not be used to endorse or promote * products derived from this software without specific prior written * permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * XXX: How do we in general know that objects referenced in events * have not been destroyed before we get around to handle the event ? */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include TAILQ_HEAD(event_tailq_head, g_event); static struct event_tailq_head g_events = TAILQ_HEAD_INITIALIZER(g_events); static u_int g_pending_events; static TAILQ_HEAD(,g_provider) g_doorstep = TAILQ_HEAD_INITIALIZER(g_doorstep); static struct mtx g_eventlock; static int g_wither_work; #define G_N_EVENTREFS 20 struct g_event { TAILQ_ENTRY(g_event) events; g_event_t *func; void *arg; int flag; void *ref[G_N_EVENTREFS]; }; #define EV_DONE 0x80000 #define EV_WAKEUP 0x40000 #define EV_CANCELED 0x20000 #define EV_INPROGRESS 0x10000 void g_waitidle(void) { g_topology_assert_not(); mtx_lock(&g_eventlock); TSWAIT("GEOM events"); while (!TAILQ_EMPTY(&g_events)) msleep(&g_pending_events, &g_eventlock, PPAUSE, "g_waitidle", hz/5); TSUNWAIT("GEOM events"); mtx_unlock(&g_eventlock); curthread->td_pflags &= ~TDP_GEOM; } #if 0 void g_waitidlelock(void) { g_topology_assert(); mtx_lock(&g_eventlock); while (!TAILQ_EMPTY(&g_events)) { g_topology_unlock(); msleep(&g_pending_events, &g_eventlock, PPAUSE, "g_waitidlel", hz/5); g_topology_lock(); } mtx_unlock(&g_eventlock); } #endif struct g_attrchanged_args { struct g_provider *pp; const char *attr; }; static void g_attr_changed_event(void *arg, int flag) { struct g_attrchanged_args *args; struct g_provider *pp; struct g_consumer *cp; struct g_consumer *next_cp; args = arg; pp = args->pp; g_topology_assert(); if (flag != EV_CANCEL && g_shutdown == 0) { /* * Tell all consumers of the change. */ LIST_FOREACH_SAFE(cp, &pp->consumers, consumers, next_cp) { if (cp->geom->attrchanged != NULL) cp->geom->attrchanged(cp, args->attr); } } g_free(args); } int g_attr_changed(struct g_provider *pp, const char *attr, int flag) { struct g_attrchanged_args *args; int error; args = g_malloc(sizeof *args, flag); if (args == NULL) return (ENOMEM); args->pp = pp; args->attr = attr; error = g_post_event(g_attr_changed_event, args, flag, pp, NULL); if (error != 0) g_free(args); return (error); } void g_orphan_provider(struct g_provider *pp, int error) { /* G_VALID_PROVIDER(pp) We likely lack topology lock */ g_trace(G_T_TOPOLOGY, "g_orphan_provider(%p(%s), %d)", pp, pp->name, error); KASSERT(error != 0, ("g_orphan_provider(%p(%s), 0) error must be non-zero\n", pp, pp->name)); pp->error = error; mtx_lock(&g_eventlock); KASSERT(!(pp->flags & G_PF_ORPHAN), ("g_orphan_provider(%p(%s)), already an orphan", pp, pp->name)); pp->flags |= G_PF_ORPHAN; TAILQ_INSERT_TAIL(&g_doorstep, pp, orphan); mtx_unlock(&g_eventlock); wakeup(&g_wait_event); } /* * This function is called once on each provider which the event handler * finds on its g_doorstep. */ static void g_orphan_register(struct g_provider *pp) { struct g_consumer *cp, *cp2; int wf; g_topology_assert(); G_VALID_PROVIDER(pp); g_trace(G_T_TOPOLOGY, "g_orphan_register(%s)", pp->name); g_cancel_event(pp); wf = pp->flags & G_PF_WITHER; pp->flags &= ~G_PF_WITHER; /* * Tell all consumers the bad news. * Don't be surprised if they self-destruct. */ LIST_FOREACH_SAFE(cp, &pp->consumers, consumers, cp2) { KASSERT(cp->geom->orphan != NULL, ("geom %s has no orphan, class %s", cp->geom->name, cp->geom->class->name)); /* * XXX: g_dev_orphan method does deferred destroying * and it is possible, that other event could already * call the orphan method. Check consumer's flags to * do not schedule it twice. */ if (cp->flags & G_CF_ORPHAN) continue; cp->flags |= G_CF_ORPHAN; cp->geom->orphan(cp); } if (LIST_EMPTY(&pp->consumers) && wf) g_destroy_provider(pp); else pp->flags |= wf; #ifdef notyet cp = LIST_FIRST(&pp->consumers); if (cp != NULL) return; if (pp->geom->flags & G_GEOM_WITHER) g_destroy_provider(pp); #endif } static int one_event(void) { struct g_event *ep; struct g_provider *pp; g_topology_assert(); mtx_lock(&g_eventlock); pp = TAILQ_FIRST(&g_doorstep); if (pp != NULL) { G_VALID_PROVIDER(pp); TAILQ_REMOVE(&g_doorstep, pp, orphan); mtx_unlock(&g_eventlock); g_orphan_register(pp); return (1); } ep = TAILQ_FIRST(&g_events); if (ep == NULL) { wakeup(&g_pending_events); return (0); } if (ep->flag & EV_INPROGRESS) { mtx_unlock(&g_eventlock); return (1); } ep->flag |= EV_INPROGRESS; mtx_unlock(&g_eventlock); g_topology_assert(); ep->func(ep->arg, 0); g_topology_assert(); mtx_lock(&g_eventlock); TSRELEASE("GEOM events"); TAILQ_REMOVE(&g_events, ep, events); ep->flag &= ~EV_INPROGRESS; if (ep->flag & EV_WAKEUP) { ep->flag |= EV_DONE; mtx_unlock(&g_eventlock); wakeup(ep); } else { mtx_unlock(&g_eventlock); g_free(ep); } return (1); } void g_run_events() { for (;;) { g_topology_lock(); while (one_event()) ; mtx_assert(&g_eventlock, MA_OWNED); if (g_wither_work) { g_wither_work = 0; mtx_unlock(&g_eventlock); g_wither_washer(); g_topology_unlock(); } else { g_topology_unlock(); msleep(&g_wait_event, &g_eventlock, PRIBIO | PDROP, "-", 0); } } /* NOTREACHED */ } void g_cancel_event(void *ref) { struct g_event *ep, *epn; struct g_provider *pp; u_int n; mtx_lock(&g_eventlock); TAILQ_FOREACH(pp, &g_doorstep, orphan) { if (pp != ref) continue; TAILQ_REMOVE(&g_doorstep, pp, orphan); break; } TAILQ_FOREACH_SAFE(ep, &g_events, events, epn) { if (ep->flag & EV_INPROGRESS) continue; for (n = 0; n < G_N_EVENTREFS; n++) { if (ep->ref[n] == NULL) break; if (ep->ref[n] != ref) continue; TSRELEASE("GEOM events"); TAILQ_REMOVE(&g_events, ep, events); ep->func(ep->arg, EV_CANCEL); mtx_assert(&g_eventlock, MA_OWNED); if (ep->flag & EV_WAKEUP) { ep->flag |= (EV_DONE|EV_CANCELED); wakeup(ep); } else { g_free(ep); } break; } } if (TAILQ_EMPTY(&g_events)) wakeup(&g_pending_events); mtx_unlock(&g_eventlock); } -static int -g_post_event_x(g_event_t *func, void *arg, int flag, int wuflag, struct g_event **epp, va_list ap) +struct g_event * +g_alloc_event(int flag) +{ + KASSERT(flag == M_WAITOK || flag == M_NOWAIT, + ("Wrong flag to g_alloc_event")); + + return (g_malloc(sizeof(struct g_event), flag | M_ZERO)); +} + +static void +g_post_event_ep_va(g_event_t *func, void *arg, int wuflag, + struct g_event *ep, va_list ap) { - struct g_event *ep; void *p; u_int n; - g_trace(G_T_TOPOLOGY, "g_post_event_x(%p, %p, %d, %d)", - func, arg, flag, wuflag); - KASSERT(wuflag == 0 || wuflag == EV_WAKEUP, - ("Wrong wuflag in g_post_event_x(0x%x)", wuflag)); - ep = g_malloc(sizeof *ep, flag | M_ZERO); - if (ep == NULL) - return (ENOMEM); ep->flag = wuflag; for (n = 0; n < G_N_EVENTREFS; n++) { p = va_arg(ap, void *); if (p == NULL) break; g_trace(G_T_TOPOLOGY, " ref %p", p); ep->ref[n] = p; } KASSERT(p == NULL, ("Too many references to event")); ep->func = func; ep->arg = arg; mtx_lock(&g_eventlock); TSHOLD("GEOM events"); TAILQ_INSERT_TAIL(&g_events, ep, events); mtx_unlock(&g_eventlock); wakeup(&g_wait_event); - if (epp != NULL) - *epp = ep; curthread->td_pflags |= TDP_GEOM; thread_lock(curthread); curthread->td_flags |= TDF_ASTPENDING; thread_unlock(curthread); +} + +void +g_post_event_ep(g_event_t *func, void *arg, struct g_event *ep, ...) +{ + va_list ap; + + va_start(ap, ep); + g_post_event_ep_va(func, arg, 0, ep, ap); + va_end(ap); +} + + +static int +g_post_event_x(g_event_t *func, void *arg, int flag, int wuflag, struct g_event **epp, va_list ap) +{ + struct g_event *ep; + + g_trace(G_T_TOPOLOGY, "g_post_event_x(%p, %p, %d, %d)", + func, arg, flag, wuflag); + KASSERT(wuflag == 0 || wuflag == EV_WAKEUP, + ("Wrong wuflag in g_post_event_x(0x%x)", wuflag)); + ep = g_alloc_event(flag); + if (ep == NULL) + return (ENOMEM); + if (epp != NULL) + *epp = ep; + g_post_event_ep_va(func, arg, wuflag, ep, ap); return (0); } int g_post_event(g_event_t *func, void *arg, int flag, ...) { va_list ap; int i; KASSERT(flag == M_WAITOK || flag == M_NOWAIT, ("Wrong flag to g_post_event")); va_start(ap, flag); i = g_post_event_x(func, arg, flag, 0, NULL, ap); va_end(ap); return (i); } void g_do_wither() { mtx_lock(&g_eventlock); g_wither_work = 1; mtx_unlock(&g_eventlock); wakeup(&g_wait_event); } /* * XXX: It might actually be useful to call this function with topology held. * XXX: This would ensure that the event gets created before anything else * XXX: changes. At present all users have a handle on things in some other * XXX: way, so this remains an XXX for now. */ int g_waitfor_event(g_event_t *func, void *arg, int flag, ...) { va_list ap; struct g_event *ep; int error; g_topology_assert_not(); KASSERT(flag == M_WAITOK || flag == M_NOWAIT, ("Wrong flag to g_post_event")); va_start(ap, flag); error = g_post_event_x(func, arg, flag, EV_WAKEUP, &ep, ap); va_end(ap); if (error) return (error); mtx_lock(&g_eventlock); while (!(ep->flag & EV_DONE)) msleep(ep, &g_eventlock, PRIBIO, "g_waitfor_event", hz); if (ep->flag & EV_CANCELED) error = EAGAIN; mtx_unlock(&g_eventlock); g_free(ep); return (error); } void g_event_init() { mtx_init(&g_eventlock, "GEOM orphanage", NULL, MTX_DEF); }