Date: Sun, 4 May 2014 15:59:32 +0000 (UTC) From: Dmitry Chagin <dchagin@FreeBSD.org> To: src-committers@freebsd.org, svn-src-user@freebsd.org Subject: svn commit: r265327 - in user/dchagin/lemul/sys: amd64/linux amd64/linux32 compat/linux conf i386/linux modules/linux modules/linux64 Message-ID: <201405041559.s44FxWdj053353@svn.freebsd.org>
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Author: dchagin Date: Sun May 4 15:59:32 2014 New Revision: 265327 URL: http://svnweb.freebsd.org/changeset/base/265327 Log: Implement epoll family system calls. This is a tiny wrapper around kqueue to implement epoll subset of functionality. The kqueue user data are 32bit on i386 which is not enough for epoll user data, so we keep user data in the proc emuldata. Initial patch developed by rdivacky in 2007, then extended by Yuri Victorovich @ r255672 and finished by me. Added: user/dchagin/lemul/sys/compat/linux/linux_event.c (contents, props changed) user/dchagin/lemul/sys/compat/linux/linux_event.h (contents, props changed) Modified: user/dchagin/lemul/sys/amd64/linux/linux_dummy.c user/dchagin/lemul/sys/amd64/linux/syscalls.master user/dchagin/lemul/sys/amd64/linux32/linux32_dummy.c user/dchagin/lemul/sys/amd64/linux32/syscalls.master user/dchagin/lemul/sys/compat/linux/linux_emul.c user/dchagin/lemul/sys/compat/linux/linux_emul.h user/dchagin/lemul/sys/conf/files.i386 user/dchagin/lemul/sys/conf/files.pc98 user/dchagin/lemul/sys/i386/linux/linux_dummy.c user/dchagin/lemul/sys/i386/linux/syscalls.master user/dchagin/lemul/sys/modules/linux/Makefile user/dchagin/lemul/sys/modules/linux64/Makefile Modified: user/dchagin/lemul/sys/amd64/linux/linux_dummy.c ============================================================================== --- user/dchagin/lemul/sys/amd64/linux/linux_dummy.c Sun May 4 15:50:32 2014 (r265326) +++ user/dchagin/lemul/sys/amd64/linux/linux_dummy.c Sun May 4 15:59:32 2014 (r265327) @@ -69,7 +69,6 @@ DUMMY(tuxcall); DUMMY(security); DUMMY(set_thread_area); DUMMY(lookup_dcookie); -DUMMY(epoll_create); DUMMY(epoll_ctl_old); DUMMY(epoll_wait_old); DUMMY(remap_file_pages); @@ -79,8 +78,6 @@ DUMMY(timer_settime); DUMMY(timer_gettime); DUMMY(timer_getoverrun); DUMMY(timer_delete); -DUMMY(epoll_ctl); -DUMMY(epoll_wait); DUMMY(mbind); DUMMY(get_mempolicy); DUMMY(set_mempolicy); @@ -117,7 +114,6 @@ DUMMY(timerfd_settime); DUMMY(timerfd_gettime); DUMMY(signalfd4); DUMMY(eventfd2); -DUMMY(epoll_create1); DUMMY(inotify_init1); DUMMY(preadv); DUMMY(pwritev); Modified: user/dchagin/lemul/sys/amd64/linux/syscalls.master ============================================================================== --- user/dchagin/lemul/sys/amd64/linux/syscalls.master Sun May 4 15:50:32 2014 (r265326) +++ user/dchagin/lemul/sys/amd64/linux/syscalls.master Sun May 4 15:59:32 2014 (r265327) @@ -373,7 +373,7 @@ 210 AUE_NULL UNIMPL linux_io_cancel 211 AUE_NULL UNIMPL linux_get_thread_area 212 AUE_NULL STD { int linux_lookup_dcookie(void); } -213 AUE_NULL STD { int linux_epoll_create(void); } +213 AUE_NULL STD { int linux_epoll_create(l_int size); } 214 AUE_NULL STD { int linux_epoll_ctl_old(void); } 215 AUE_NULL STD { int linux_epoll_wait_old(void); } 216 AUE_NULL STD { int linux_remap_file_pages(void); } @@ -395,8 +395,10 @@ 230 AUE_NULL STD { int linux_clock_nanosleep(clockid_t which, int flags, \ struct l_timespec *rqtp, struct l_timespec *rmtp); } 231 AUE_EXIT STD { int linux_exit_group(int error_code); } -232 AUE_NULL STD { int linux_epoll_wait(void); } -233 AUE_NULL STD { int linux_epoll_ctl(void); } +232 AUE_NULL STD { int linux_epoll_wait(l_int epfd, struct epoll_event *events, \ + l_int maxevents, l_int timeout); } +233 AUE_NULL STD { int linux_epoll_ctl(l_int epfd, l_int op, l_int fd, \ + struct epoll_event *event); } 234 AUE_NULL STD { int linux_tgkill(int tgid, int pid, int sig); } 235 AUE_UTIMES STD { int linux_utimes(char *fname, \ struct l_timeval *tptr); } @@ -464,7 +466,8 @@ 278 AUE_NULL STD { int linux_vmsplice(void); } 279 AUE_NULL STD { int linux_move_pages(void); } 280 AUE_NULL STD { int linux_utimensat(void); } -281 AUE_NULL STD { int linux_epoll_pwait(void); } +281 AUE_NULL STD { int linux_epoll_pwait(l_int epfd, struct epoll_event *events, \ + l_int maxevents, l_int timeout, l_sigset_t *mask); } 282 AUE_NULL STD { int linux_signalfd(void); } 283 AUE_NULL STD { int linux_timerfd(void); } 284 AUE_NULL STD { int linux_eventfd(void); } @@ -475,7 +478,7 @@ l_uintptr_t namelen, int flags); } 289 AUE_NULL STD { int linux_signalfd4(void); } 290 AUE_NULL STD { int linux_eventfd2(void); } -291 AUE_NULL STD { int linux_epoll_create1(void); } +291 AUE_NULL STD { int linux_epoll_create1(l_int flags); } 292 AUE_NULL STD { int linux_dup3(l_int oldfd, \ l_int newfd, l_int flags); } 293 AUE_NULL STD { int linux_pipe2(l_int *pipefds, l_int flags); } Modified: user/dchagin/lemul/sys/amd64/linux32/linux32_dummy.c ============================================================================== --- user/dchagin/lemul/sys/amd64/linux32/linux32_dummy.c Sun May 4 15:50:32 2014 (r265326) +++ user/dchagin/lemul/sys/amd64/linux32/linux32_dummy.c Sun May 4 15:59:32 2014 (r265327) @@ -68,9 +68,6 @@ DUMMY(pivot_root); DUMMY(mincore); DUMMY(ptrace); DUMMY(lookup_dcookie); -DUMMY(epoll_create); -DUMMY(epoll_ctl); -DUMMY(epoll_wait); DUMMY(remap_file_pages); DUMMY(timer_create); DUMMY(timer_settime); @@ -125,7 +122,6 @@ DUMMY(timerfd_gettime); /* linux 2.6.27: */ DUMMY(signalfd4); DUMMY(eventfd2); -DUMMY(epoll_create1); DUMMY(inotify_init1); /* linux 2.6.30: */ DUMMY(preadv); Modified: user/dchagin/lemul/sys/amd64/linux32/syscalls.master ============================================================================== --- user/dchagin/lemul/sys/amd64/linux32/syscalls.master Sun May 4 15:50:32 2014 (r265326) +++ user/dchagin/lemul/sys/amd64/linux32/syscalls.master Sun May 4 15:59:32 2014 (r265327) @@ -430,9 +430,11 @@ 251 AUE_NULL UNIMPL 252 AUE_EXIT STD { int linux_exit_group(int error_code); } 253 AUE_NULL STD { int linux_lookup_dcookie(void); } -254 AUE_NULL STD { int linux_epoll_create(void); } -255 AUE_NULL STD { int linux_epoll_ctl(void); } -256 AUE_NULL STD { int linux_epoll_wait(void); } +254 AUE_NULL STD { int linux_epoll_create(l_int size); } +255 AUE_NULL STD { int linux_epoll_ctl(l_int epfd, l_int op, l_int fd, \ + struct epoll_event *event); } +256 AUE_NULL STD { int linux_epoll_wait(l_int epfd, struct epoll_event *events, \ + l_int maxevents, l_int timeout); } 257 AUE_NULL STD { int linux_remap_file_pages(void); } 258 AUE_NULL STD { int linux_set_tid_address(int *tidptr); } 259 AUE_NULL STD { int linux_timer_create(void); } @@ -524,7 +526,8 @@ 317 AUE_NULL STD { int linux_move_pages(void); } ; linux 2.6.19: 318 AUE_NULL STD { int linux_getcpu(void); } -319 AUE_NULL STD { int linux_epoll_pwait(void); } +319 AUE_NULL STD { int linux_epoll_pwait(l_int epfd, struct epoll_event *events, \ + l_int maxevents, l_int timeout, l_osigset_t *mask); } ; linux 2.6.22: 320 AUE_NULL STD { int linux_utimensat(void); } 321 AUE_NULL STD { int linux_signalfd(void); } @@ -538,7 +541,7 @@ ; linux 2.6.27: 327 AUE_NULL STD { int linux_signalfd4(void); } 328 AUE_NULL STD { int linux_eventfd2(void); } -329 AUE_NULL STD { int linux_epoll_create1(void); } +329 AUE_NULL STD { int linux_epoll_create1(l_int flags); } 330 AUE_NULL STD { int linux_dup3(l_int oldfd, \ l_int newfd, l_int flags); } 331 AUE_NULL STD { int linux_pipe2(l_int *pipefds, l_int flags); } Modified: user/dchagin/lemul/sys/compat/linux/linux_emul.c ============================================================================== --- user/dchagin/lemul/sys/compat/linux/linux_emul.c Sun May 4 15:50:32 2014 (r265326) +++ user/dchagin/lemul/sys/compat/linux/linux_emul.c Sun May 4 15:59:32 2014 (r265327) @@ -58,6 +58,7 @@ __FBSDID("$FreeBSD$"); #include <compat/linux/linux_dtrace.h> #include <compat/linux/linux_emul.h> +#include <compat/linux/linux_event.h> #include <compat/linux/linux_futex.h> #include <compat/linux/linux_misc.h> #include <compat/linux/linux_util.h> @@ -212,6 +213,8 @@ linux_common_execve(struct thread *td, s KASSERT(pem != NULL, ("proc_exit: proc emuldata not found.\n")); p->p_emuldata = NULL; + epoll_destroy_emuldata(pem); + sx_destroy(&pem->pem_sx); free(pem, M_TEMP); free(em, M_TEMP); @@ -395,6 +398,8 @@ linux_proc_exit(void *arg, struct proc * KASSERT(pem != NULL, ("proc_exit: proc emuldata not found.\n")); p->p_emuldata = NULL; + epoll_destroy_emuldata(pem); + sx_destroy(&pem->pem_sx); free(pem, M_TEMP); } Modified: user/dchagin/lemul/sys/compat/linux/linux_emul.h ============================================================================== --- user/dchagin/lemul/sys/compat/linux/linux_emul.h Sun May 4 15:50:32 2014 (r265326) +++ user/dchagin/lemul/sys/compat/linux/linux_emul.h Sun May 4 15:59:32 2014 (r265327) @@ -60,9 +60,12 @@ void linux_thread_detach(struct thread * /* process emuldata flags */ #define LINUX_XDEPR_REQUEUEOP 0x00000001 /* uses deprecated futex REQUEUE op*/ +#define LINUX_XUNSUP_EPOLL 0x00000002 /* unsupported epoll events */ + struct linux_pemuldata { uint32_t flags; /* different emuldata flags */ struct sx pem_sx; /* lock for this struct */ + void *epoll; /* epoll data */ }; #define LINUX_PEM_XLOCK(p) sx_xlock(&(p)->pem_sx) Added: user/dchagin/lemul/sys/compat/linux/linux_event.c ============================================================================== --- /dev/null 00:00:00 1970 (empty, because file is newly added) +++ user/dchagin/lemul/sys/compat/linux/linux_event.c Sun May 4 15:59:32 2014 (r265327) @@ -0,0 +1,982 @@ +/*- + * Copyright (c) 2007 Roman Divacky + * Copyright (c) 2014 Dmitry Chagin + * 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 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. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include "opt_compat.h" + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/imgact.h> +#include <sys/kernel.h> +#include <sys/limits.h> +#include <sys/lock.h> +#include <sys/mutex.h> +#include <sys/capability.h> +#include <sys/types.h> +#include <sys/file.h> +#include <sys/filedesc.h> +#include <sys/errno.h> +#include <sys/event.h> +#include <sys/proc.h> +#include <sys/sx.h> +#include <sys/syscallsubr.h> +#include <sys/timespec.h> + +#ifdef COMPAT_LINUX32 +#include <machine/../linux32/linux.h> +#include <machine/../linux32/linux32_proto.h> +#else +#include <machine/../linux/linux.h> +#include <machine/../linux/linux_proto.h> +#endif + +#include <compat/linux/linux_emul.h> +#include <compat/linux/linux_event.h> +#include <compat/linux/linux_file.h> +#include <compat/linux/linux_util.h> + +/* + * epoll defines 'struct epoll_event' with the field 'data' as 64 bits + * on all architectures. But on 32 bit architectures BSD 'struct kevent' only + * has 32 bit opaque pointer as 'udata' field. So we can't pass epoll supplied + * data verbatuim. Therefore we allocate 64-bit memory block to pass + * user supplied data for every file descriptor. + */ + +typedef uint64_t epoll_udata_t; + +struct epoll_emuldata { + uint32_t fdc; /* epoll udata count */ + epoll_udata_t udata[1]; /* epoll file udata */ +}; + +#define EPOLL_DEF_SZ 16 +#define EPOLL_SIZE(fdn) \ + (sizeof(struct epoll_emuldata)+(fdn) * sizeof(epoll_udata_t)) + +struct epoll_event { + uint32_t events; + epoll_udata_t data; +}; + +#define LINUX_MAX_EVENTS (INT_MAX / sizeof(struct epoll_event)) + +static void epoll_fd_install(struct thread *td, int fd, epoll_udata_t udata); +static int epoll_to_kevent(struct thread *td, struct file *epfp, + int fd, struct epoll_event *l_event, int *kev_flags, + struct kevent *kevent, int *nkevents); +static void kevent_to_epoll(struct kevent *kevent, struct epoll_event *l_event); +static int epoll_kev_copyout(void *arg, struct kevent *kevp, int count); +static int epoll_kev_copyin(void *arg, struct kevent *kevp, int count); +static int epoll_delete_event(struct thread *td, struct file *epfp, + int fd, int filter); +static int epoll_delete_all_events(struct thread *td, struct file *epfp, + int fd); + +struct epoll_copyin_args { + struct kevent *changelist; +}; + +struct epoll_copyout_args { + struct epoll_event *leventlist; + struct proc *p; + uint32_t count; + int error; +}; + + +static void +epoll_fd_install(struct thread *td, int fd, epoll_udata_t udata) +{ + struct linux_pemuldata *pem; + struct epoll_emuldata *emd; + struct proc *p; + + p = td->td_proc; + + pem = pem_find(p); + KASSERT(pem != NULL, ("epoll proc emuldata not found.\n")); + + LINUX_PEM_XLOCK(pem); + if (pem->epoll == NULL) { + emd = malloc(EPOLL_SIZE(fd), M_TEMP, M_WAITOK); + emd->fdc = fd; + pem->epoll = emd; + } else { + emd = pem->epoll; + if (fd > emd->fdc) { + emd = realloc(emd, EPOLL_SIZE(fd), M_TEMP, M_WAITOK); + emd->fdc = fd; + pem->epoll = emd; + } + } + emd->udata[fd] = udata; + LINUX_PEM_XUNLOCK(pem); +} + +static int +epoll_create_common(struct thread *td, int flags) +{ + int error; + + error = kern_kqueue(td, flags); + if (error) + return (error); + + epoll_fd_install(td, EPOLL_DEF_SZ, 0); + + return (0); +} + +int +linux_epoll_create(struct thread *td, struct linux_epoll_create_args *args) +{ + + /* + * args->size is unused. Linux just tests it + * and then forgets it as well. + */ + if (args->size <= 0) + return (EINVAL); + + return (epoll_create_common(td, 0)); +} + +int +linux_epoll_create1(struct thread *td, struct linux_epoll_create1_args *args) +{ + int flags; + + if ((args->flags & ~(LINUX_O_CLOEXEC)) != 0) + return (EINVAL); + + flags = 0; + if ((args->flags & LINUX_O_CLOEXEC) != 0) + flags |= O_CLOEXEC; + + return (epoll_create_common(td, flags)); +} + +/* Structure converting function from epoll to kevent. */ +static int +epoll_to_kevent(struct thread *td, struct file *epfp, + int fd, struct epoll_event *l_event, int *kev_flags, + struct kevent *kevent, int *nkevents) +{ + uint32_t levents = l_event->events; + struct linux_pemuldata *pem; + struct proc *p; + + /* flags related to how event is registered */ + if ((levents & LINUX_EPOLLONESHOT) != 0) + *kev_flags |= EV_ONESHOT; + if ((levents & LINUX_EPOLLET) != 0) + *kev_flags |= EV_CLEAR; + + /* flags related to what event is registered */ + if ((levents & LINUX_EPOLL_EVRD) != 0) { + EV_SET(kevent++, fd, EVFILT_READ, *kev_flags, 0, 0, 0); + ++(*nkevents); + } + if ((levents & LINUX_EPOLL_EVWR) != 0) { + EV_SET(kevent++, fd, EVFILT_WRITE, *kev_flags, 0, 0, 0); + ++(*nkevents); + } + + if ((levents & ~(LINUX_EPOLL_EVSUP)) != 0) { + p = td->td_proc; + + pem = pem_find(p); + KASSERT(pem != NULL, ("epoll proc emuldata not found.\n")); + KASSERT(pem->epoll != NULL, ("epoll proc epolldata not found.\n")); + + LINUX_PEM_XLOCK(pem); + if ((pem->flags & LINUX_XUNSUP_EPOLL) == 0) { + pem->flags |= LINUX_XUNSUP_EPOLL; + LINUX_PEM_XUNLOCK(pem); + linux_msg(td, "epoll_ctl unsupported flags: 0x%x\n", + levents); + } else + LINUX_PEM_XUNLOCK(pem); + return (EINVAL); + } + + return (0); +} + +/* + * Structure converting function from kevent to epoll. In a case + * this is called on error in registration we store the error in + * event->data and pick it up later in linux_epoll_ctl(). + */ +static void +kevent_to_epoll(struct kevent *kevent, struct epoll_event *l_event) +{ + + if ((kevent->flags & EV_ERROR) != 0) + return; + + switch (kevent->filter) { + case EVFILT_READ: + l_event->events = LINUX_EPOLLIN|LINUX_EPOLLRDNORM|LINUX_EPOLLPRI; + break; + case EVFILT_WRITE: + l_event->events = LINUX_EPOLLOUT|LINUX_EPOLLWRNORM; + break; + } +} + +/* + * Copyout callback used by kevent. This converts kevent + * events to epoll events and copies them back to the + * userspace. This is also called on error on registering + * of the filter. + */ +static int +epoll_kev_copyout(void *arg, struct kevent *kevp, int count) +{ + struct epoll_copyout_args *args; + struct linux_pemuldata *pem; + struct epoll_emuldata *emd; + struct epoll_event *eep; + int error, fd, i; + + args = (struct epoll_copyout_args*) arg; + eep = malloc(sizeof(*eep) * count, M_TEMP, M_WAITOK | M_ZERO); + + pem = pem_find(args->p); + KASSERT(pem != NULL, ("epoll proc emuldata not found.\n")); + LINUX_PEM_SLOCK(pem); + emd = pem->epoll; + KASSERT(emd != NULL, ("epoll proc epolldata not found.\n")); + + for (i = 0; i < count; i++) { + kevent_to_epoll(&kevp[i], &eep[i]); + + fd = kevp[i].ident; + KASSERT(fd < emd->fdc, ("epoll user data vector" + " is too small.\n")); + eep->data = emd->udata[fd]; + } + LINUX_PEM_SUNLOCK(pem); + + error = copyout(eep, args->leventlist, count * sizeof(*eep)); + if (error == 0) { + args->leventlist += count; + args->count += count; + } else if (args->error == 0) + args->error = error; + + free(eep, M_TEMP); + return (error); +} + +/* + * Copyin callback used by kevent. This copies already + * converted filters from kernel memory to the kevent + * internal kernel memory. Hence the memcpy instead of + * copyin. + */ +static int +epoll_kev_copyin(void *arg, struct kevent *kevp, int count) +{ + struct epoll_copyin_args *args; + + args = (struct epoll_copyin_args*) arg; + + memcpy(kevp, args->changelist, count * sizeof(*kevp)); + args->changelist += count; + + return (0); +} + +/* + * Load epoll filter, convert it to kevent filter + * and load it into kevent subsystem. + */ +int +linux_epoll_ctl(struct thread *td, struct linux_epoll_ctl_args *args) +{ + struct file *epfp; + struct epoll_copyin_args ciargs; + struct kevent kev[2]; + struct kevent_copyops k_ops = { &ciargs, + NULL, + epoll_kev_copyin}; + struct epoll_event le; + cap_rights_t rights; + int kev_flags; + int nchanges = 0; + int error; + + if (args->epfd == args->fd) + return (EINVAL); + + if (args->op != LINUX_EPOLL_CTL_DEL) { + error = copyin(args->event, &le, sizeof(le)); + if (error != 0) + return (error); + } + + error = fget(td, args->epfd, cap_rights_init(&rights, CAP_POLL_EVENT), &epfp); + if (error != 0) + return (error); + + ciargs.changelist = kev; + + switch (args->op) { + case LINUX_EPOLL_CTL_MOD: + /* + * We don't memorize which events were set for this FD + * on this level, so just delete all we could have set: + * EVFILT_READ and EVFILT_WRITE, ignoring any errors + */ + error = epoll_delete_all_events(td, epfp, args->fd); + if (error) + goto leave; + /* FALLTHROUGH */ + + case LINUX_EPOLL_CTL_ADD: + kev_flags = EV_ADD | EV_ENABLE; + break; + + case LINUX_EPOLL_CTL_DEL: + /* CTL_DEL means unregister this fd with this epoll */ + error = epoll_delete_all_events(td, epfp, args->fd); + goto leave; + + default: + error = EINVAL; + goto leave; + } + + error = epoll_to_kevent(td, epfp, args->fd, &le, &kev_flags, kev, &nchanges); + if (error) + goto leave; + + epoll_fd_install(td, args->fd, le.data); + + error = kern_kevent(td, args->epfd, nchanges, 0, &k_ops, NULL); + +leave: + fdrop(epfp, td); + return (error); +} + +/* + * Wait for a filter to be triggered on the epoll file descriptor. + */ +int +linux_epoll_wait(struct thread *td, struct linux_epoll_wait_args *args) +{ + struct file *epfp; + struct timespec ts, *tsp; + cap_rights_t rights; + struct epoll_copyout_args coargs; + struct kevent_copyops k_ops = { &coargs, + epoll_kev_copyout, + NULL}; + int error; + + if (args->maxevents <= 0 || args->maxevents > LINUX_MAX_EVENTS) + return (EINVAL); + + error = fget(td, args->epfd, cap_rights_init(&rights, CAP_POLL_EVENT), &epfp); + if (error != 0) + return (error); + + coargs.leventlist = args->events; + coargs.p = td->td_proc; + coargs.count = 0; + coargs.error = 0; + + if (args->timeout != -1) { + if (args->timeout < 0) { + error = EINVAL; + goto leave; + } + /* Convert from milliseconds to timespec. */ + ts.tv_sec = args->timeout / 1000; + ts.tv_nsec = (args->timeout % 1000) * 1000000; + tsp = &ts; + } else { + tsp = NULL; + } + + error = kern_kevent(td, args->epfd, 0, args->maxevents, &k_ops, tsp); + if (error == 0 && coargs.error != 0) + error = coargs.error; + + /* + * kern_kevent might return ENOMEM which is not expected from epoll_wait. + * Maybe we should translate that but I don't think it matters at all. + */ + if (error == 0) + td->td_retval[0] = coargs.count; +leave: + fdrop(epfp, td); + return (error); +} + +static int +epoll_delete_event(struct thread *td, struct file *epfp, int fd, int filter) +{ + struct epoll_copyin_args ciargs; + struct kevent kev; + struct kevent_copyops k_ops = { &ciargs, + NULL, + epoll_kev_copyin}; + int error; + + ciargs.changelist = &kev; + EV_SET(&kev, fd, filter, EV_DELETE | EV_DISABLE, 0, 0, 0); + + error = kern_kevent(td, fd, 1, 0, &k_ops, NULL); + + /* + * here we ignore ENONT, because we don't keep track of events here + */ + if (error == ENOENT) + error = 0; + return (error); +} + +static int +epoll_delete_all_events(struct thread *td, struct file *epfp, int fd) +{ + int error1, error2; + + error1 = epoll_delete_event(td, epfp, fd, EVFILT_READ); + error2 = epoll_delete_event(td, epfp, fd, EVFILT_WRITE); + + /* report any errors we got */ + return (error1 == 0 ? error2 : error1); +} + +void +epoll_destroy_emuldata(struct linux_pemuldata *pem) +{ + struct epoll_emuldata *emd; + + if (pem->epoll == NULL) + return; + emd = pem->epoll; + free(emd, M_TEMP); +} +/*- + * Copyright (c) 2007 Roman Divacky + * Copyright (c) 2014 Dmitry Chagin + * 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 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. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include "opt_compat.h" + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/imgact.h> +#include <sys/kernel.h> +#include <sys/limits.h> +#include <sys/lock.h> +#include <sys/mutex.h> +#include <sys/capability.h> +#include <sys/types.h> +#include <sys/file.h> +#include <sys/filedesc.h> +#include <sys/errno.h> +#include <sys/event.h> +#include <sys/proc.h> +#include <sys/sx.h> +#include <sys/syscallsubr.h> +#include <sys/timespec.h> + +#ifdef COMPAT_LINUX32 +#include <machine/../linux32/linux.h> +#include <machine/../linux32/linux32_proto.h> +#else +#include <machine/../linux/linux.h> +#include <machine/../linux/linux_proto.h> +#endif + +#include <compat/linux/linux_emul.h> +#include <compat/linux/linux_event.h> +#include <compat/linux/linux_file.h> +#include <compat/linux/linux_util.h> + +/* + * epoll defines 'struct epoll_event' with the field 'data' as 64 bits + * on all architectures. But on 32 bit architectures BSD 'struct kevent' only + * has 32 bit opaque pointer as 'udata' field. So we can't pass epoll supplied + * data verbatuim. Therefore we allocate 64-bit memory block to pass + * user supplied data for every file descriptor. + */ + +typedef uint64_t epoll_udata_t; + +struct epoll_emuldata { + uint32_t fdc; /* epoll udata count */ + epoll_udata_t udata[1]; /* epoll file udata */ +}; + +#define EPOLL_DEF_SZ 16 +#define EPOLL_SIZE(fdn) \ + (sizeof(struct epoll_emuldata)+(fdn) * sizeof(epoll_udata_t)) + +struct epoll_event { + uint32_t events; + epoll_udata_t data; +}; + +#define LINUX_MAX_EVENTS (INT_MAX / sizeof(struct epoll_event)) + +static void epoll_fd_install(struct thread *td, int fd, epoll_udata_t udata); +static int epoll_to_kevent(struct thread *td, struct file *epfp, + int fd, struct epoll_event *l_event, int *kev_flags, + struct kevent *kevent, int *nkevents); +static void kevent_to_epoll(struct kevent *kevent, struct epoll_event *l_event); +static int epoll_kev_copyout(void *arg, struct kevent *kevp, int count); +static int epoll_kev_copyin(void *arg, struct kevent *kevp, int count); +static int epoll_delete_event(struct thread *td, struct file *epfp, + int fd, int filter); +static int epoll_delete_all_events(struct thread *td, struct file *epfp, + int fd); + +struct epoll_copyin_args { + struct kevent *changelist; +}; + +struct epoll_copyout_args { + struct epoll_event *leventlist; + struct proc *p; + uint32_t count; + int error; +}; + + +static void +epoll_fd_install(struct thread *td, int fd, epoll_udata_t udata) +{ + struct linux_pemuldata *pem; + struct epoll_emuldata *emd; + struct proc *p; + + p = td->td_proc; + + pem = pem_find(p); + KASSERT(pem != NULL, ("epoll proc emuldata not found.\n")); + + LINUX_PEM_XLOCK(pem); + if (pem->epoll == NULL) { + emd = malloc(EPOLL_SIZE(fd), M_TEMP, M_WAITOK); + emd->fdc = fd; + pem->epoll = emd; + } else { + emd = pem->epoll; + if (fd > emd->fdc) { + emd = realloc(emd, EPOLL_SIZE(fd), M_TEMP, M_WAITOK); + emd->fdc = fd; + pem->epoll = emd; + } + } + emd->udata[fd] = udata; + LINUX_PEM_XUNLOCK(pem); +} + +static int +epoll_create_common(struct thread *td, int flags) +{ + int error; + + error = kern_kqueue(td, flags); + if (error) + return (error); + + epoll_fd_install(td, EPOLL_DEF_SZ, 0); + + return (0); +} + +int +linux_epoll_create(struct thread *td, struct linux_epoll_create_args *args) +{ + + /* + * args->size is unused. Linux just tests it + * and then forgets it as well. + */ + if (args->size <= 0) + return (EINVAL); + + return (epoll_create_common(td, 0)); +} + +int +linux_epoll_create1(struct thread *td, struct linux_epoll_create1_args *args) +{ + int flags; + + if ((args->flags & ~(LINUX_O_CLOEXEC)) != 0) + return (EINVAL); + + flags = 0; + if ((args->flags & LINUX_O_CLOEXEC) != 0) + flags |= O_CLOEXEC; + + return (epoll_create_common(td, flags)); +} + +/* Structure converting function from epoll to kevent. */ +static int +epoll_to_kevent(struct thread *td, struct file *epfp, + int fd, struct epoll_event *l_event, int *kev_flags, + struct kevent *kevent, int *nkevents) +{ + uint32_t levents = l_event->events; + struct linux_pemuldata *pem; + struct proc *p; + + /* flags related to how event is registered */ + if ((levents & LINUX_EPOLLONESHOT) != 0) + *kev_flags |= EV_ONESHOT; + if ((levents & LINUX_EPOLLET) != 0) + *kev_flags |= EV_CLEAR; + + /* flags related to what event is registered */ + if ((levents & LINUX_EPOLL_EVRD) != 0) { + EV_SET(kevent++, fd, EVFILT_READ, *kev_flags, 0, 0, 0); + ++(*nkevents); + } + if ((levents & LINUX_EPOLL_EVWR) != 0) { + EV_SET(kevent++, fd, EVFILT_WRITE, *kev_flags, 0, 0, 0); + ++(*nkevents); + } + + if ((levents & ~(LINUX_EPOLL_EVSUP)) != 0) { + p = td->td_proc; + + pem = pem_find(p); + KASSERT(pem != NULL, ("epoll proc emuldata not found.\n")); + KASSERT(pem->epoll != NULL, ("epoll proc epolldata not found.\n")); + + LINUX_PEM_XLOCK(pem); + if ((pem->flags & LINUX_XUNSUP_EPOLL) == 0) { + pem->flags |= LINUX_XUNSUP_EPOLL; + LINUX_PEM_XUNLOCK(pem); + linux_msg(td, "epoll_ctl unsupported flags: 0x%x\n", + levents); + } else + LINUX_PEM_XUNLOCK(pem); + return (EINVAL); + } + + return (0); +} + +/* + * Structure converting function from kevent to epoll. In a case + * this is called on error in registration we store the error in + * event->data and pick it up later in linux_epoll_ctl(). + */ +static void +kevent_to_epoll(struct kevent *kevent, struct epoll_event *l_event) +{ + + if ((kevent->flags & EV_ERROR) != 0) + return; + + switch (kevent->filter) { + case EVFILT_READ: + l_event->events = LINUX_EPOLLIN|LINUX_EPOLLRDNORM|LINUX_EPOLLPRI; + break; + case EVFILT_WRITE: + l_event->events = LINUX_EPOLLOUT|LINUX_EPOLLWRNORM; + break; + } +} + +/* + * Copyout callback used by kevent. This converts kevent + * events to epoll events and copies them back to the + * userspace. This is also called on error on registering + * of the filter. + */ +static int +epoll_kev_copyout(void *arg, struct kevent *kevp, int count) +{ + struct epoll_copyout_args *args; + struct linux_pemuldata *pem; + struct epoll_emuldata *emd; + struct epoll_event *eep; + int error, fd, i; + + args = (struct epoll_copyout_args*) arg; + eep = malloc(sizeof(*eep) * count, M_TEMP, M_WAITOK | M_ZERO); + + pem = pem_find(args->p); + KASSERT(pem != NULL, ("epoll proc emuldata not found.\n")); + LINUX_PEM_SLOCK(pem); + emd = pem->epoll; + KASSERT(emd != NULL, ("epoll proc epolldata not found.\n")); + + for (i = 0; i < count; i++) { + kevent_to_epoll(&kevp[i], &eep[i]); + + fd = kevp[i].ident; + KASSERT(fd < emd->fdc, ("epoll user data vector" + " is too small.\n")); + eep->data = emd->udata[fd]; + } + LINUX_PEM_SUNLOCK(pem); + + error = copyout(eep, args->leventlist, count * sizeof(*eep)); + if (error == 0) { + args->leventlist += count; + args->count += count; + } else if (args->error == 0) + args->error = error; + + free(eep, M_TEMP); + return (error); +} + +/* + * Copyin callback used by kevent. This copies already + * converted filters from kernel memory to the kevent + * internal kernel memory. Hence the memcpy instead of + * copyin. + */ +static int +epoll_kev_copyin(void *arg, struct kevent *kevp, int count) +{ + struct epoll_copyin_args *args; + + args = (struct epoll_copyin_args*) arg; + + memcpy(kevp, args->changelist, count * sizeof(*kevp)); + args->changelist += count; + + return (0); +} + +/* + * Load epoll filter, convert it to kevent filter + * and load it into kevent subsystem. + */ +int +linux_epoll_ctl(struct thread *td, struct linux_epoll_ctl_args *args) +{ + struct file *epfp; + struct epoll_copyin_args ciargs; + struct kevent kev[2]; + struct kevent_copyops k_ops = { &ciargs, + NULL, + epoll_kev_copyin}; + struct epoll_event le; + cap_rights_t rights; + int kev_flags; + int nchanges = 0; + int error; + *** DIFF OUTPUT TRUNCATED AT 1000 LINES ***
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