diff options
Diffstat (limited to 'sys/compat/linux/linux_emul.c')
| -rw-r--r-- | sys/compat/linux/linux_emul.c | 474 |
1 files changed, 474 insertions, 0 deletions
diff --git a/sys/compat/linux/linux_emul.c b/sys/compat/linux/linux_emul.c new file mode 100644 index 0000000..61156ba --- /dev/null +++ b/sys/compat/linux/linux_emul.c @@ -0,0 +1,474 @@ +/*- + * Copyright (c) 2006 Roman Divacky + * 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 + * in this position and unchanged. + * 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 name of the author 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 ``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 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 "opt_kdtrace.h" + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/imgact.h> +#include <sys/kernel.h> +#include <sys/lock.h> +#include <sys/malloc.h> +#include <sys/mutex.h> +#include <sys/sdt.h> +#include <sys/sx.h> +#include <sys/proc.h> +#include <sys/syscallsubr.h> +#include <sys/sysent.h> +#include <sys/sysproto.h> +#include <sys/unistd.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_dtrace.h> +#include <compat/linux/linux_emul.h> +#include <compat/linux/linux_futex.h> +#include <compat/linux/linux_misc.h> + +/** + * Special DTrace provider for the linuxulator. + * + * In this file we define the provider for the entire linuxulator. All + * modules (= files of the linuxulator) use it. + * + * We define a different name depending on the emulated bitsize, see + * ../../<ARCH>/linux{,32}/linux.h, e.g.: + * native bitsize = linuxulator + * amd64, 32bit emulation = linuxulator32 + */ +LIN_SDT_PROVIDER_DEFINE(LINUX_DTRACE); + +/** + * Special DTrace module "locks", it covers some linuxulator internal + * locks. + */ +LIN_SDT_PROBE_DEFINE1(locks, emul_lock, locked, "struct mtx *"); +LIN_SDT_PROBE_DEFINE1(locks, emul_lock, unlock, "struct mtx *"); +LIN_SDT_PROBE_DEFINE1(locks, emul_shared_rlock, locked, "struct sx *"); +LIN_SDT_PROBE_DEFINE1(locks, emul_shared_rlock, unlock, "struct sx *"); +LIN_SDT_PROBE_DEFINE1(locks, emul_shared_wlock, locked, "struct sx *"); +LIN_SDT_PROBE_DEFINE1(locks, emul_shared_wlock, unlock, "struct sx *"); + +/** + * DTrace probes in this module. + */ +LIN_SDT_PROBE_DEFINE2(emul, em_find, entry, "struct proc *", "int"); +LIN_SDT_PROBE_DEFINE0(emul, em_find, return); +LIN_SDT_PROBE_DEFINE3(emul, proc_init, entry, "struct thread *", "pid_t", + "int"); +LIN_SDT_PROBE_DEFINE0(emul, proc_init, create_thread); +LIN_SDT_PROBE_DEFINE0(emul, proc_init, fork); +LIN_SDT_PROBE_DEFINE0(emul, proc_init, exec); +LIN_SDT_PROBE_DEFINE0(emul, proc_init, return); +LIN_SDT_PROBE_DEFINE1(emul, proc_exit, entry, "struct proc *"); +LIN_SDT_PROBE_DEFINE0(emul, proc_exit, futex_failed); +LIN_SDT_PROBE_DEFINE3(emul, proc_exit, reparent, "pid_t", "pid_t", + "struct proc *"); +LIN_SDT_PROBE_DEFINE1(emul, proc_exit, child_clear_tid_error, "int"); +LIN_SDT_PROBE_DEFINE0(emul, proc_exit, return); +LIN_SDT_PROBE_DEFINE2(emul, proc_exec, entry, "struct proc *", + "struct image_params *"); +LIN_SDT_PROBE_DEFINE0(emul, proc_exec, return); +LIN_SDT_PROBE_DEFINE0(emul, linux_schedtail, entry); +LIN_SDT_PROBE_DEFINE1(emul, linux_schedtail, copyout_error, "int"); +LIN_SDT_PROBE_DEFINE0(emul, linux_schedtail, return); +LIN_SDT_PROBE_DEFINE1(emul, linux_set_tid_address, entry, "int *"); +LIN_SDT_PROBE_DEFINE0(emul, linux_set_tid_address, return); +LIN_SDT_PROBE_DEFINE2(emul, linux_kill_threads, entry, "struct thread *", + "int"); +LIN_SDT_PROBE_DEFINE1(emul, linux_kill_threads, kill, "pid_t"); +LIN_SDT_PROBE_DEFINE0(emul, linux_kill_threads, return); + +struct sx emul_shared_lock; +struct mtx emul_lock; + +/* this returns locked reference to the emuldata entry (if found) */ +struct linux_emuldata * +em_find(struct proc *p, int locked) +{ + struct linux_emuldata *em; + + LIN_SDT_PROBE2(emul, em_find, entry, p, locked); + + if (locked == EMUL_DOLOCK) + EMUL_LOCK(&emul_lock); + + em = p->p_emuldata; + + if (em == NULL && locked == EMUL_DOLOCK) + EMUL_UNLOCK(&emul_lock); + + LIN_SDT_PROBE1(emul, em_find, return, em); + return (em); +} + +int +linux_proc_init(struct thread *td, pid_t child, int flags) +{ + struct linux_emuldata *em, *p_em; + struct proc *p; + + LIN_SDT_PROBE3(emul, proc_init, entry, td, child, flags); + + if (child != 0) { + /* fork or create a thread */ + em = malloc(sizeof *em, M_LINUX, M_WAITOK | M_ZERO); + em->pid = child; + em->pdeath_signal = 0; + em->flags = 0; + em->robust_futexes = NULL; + if (flags & LINUX_CLONE_THREAD) { + /* handled later in the code */ + LIN_SDT_PROBE0(emul, proc_init, create_thread); + } else { + struct linux_emuldata_shared *s; + + LIN_SDT_PROBE0(emul, proc_init, fork); + + s = malloc(sizeof *s, M_LINUX, M_WAITOK | M_ZERO); + s->refs = 1; + s->group_pid = child; + + LIST_INIT(&s->threads); + em->shared = s; + } + } else { + /* exec */ + LIN_SDT_PROBE0(emul, proc_init, exec); + + /* lookup the old one */ + em = em_find(td->td_proc, EMUL_DOLOCK); + KASSERT(em != NULL, ("proc_init: emuldata not found in exec case.\n")); + } + + em->child_clear_tid = NULL; + em->child_set_tid = NULL; + + /* + * allocate the shared struct only in clone()/fork cases in the case + * of clone() td = calling proc and child = pid of the newly created + * proc + */ + if (child != 0) { + if (flags & LINUX_CLONE_THREAD) { + /* lookup the parent */ + /* + * we dont have to lock the p_em because + * its waiting for us in linux_clone so + * there is no chance of it changing the + * p_em->shared address + */ + p_em = em_find(td->td_proc, EMUL_DONTLOCK); + KASSERT(p_em != NULL, ("proc_init: parent emuldata not found for CLONE_THREAD\n")); + em->shared = p_em->shared; + EMUL_SHARED_WLOCK(&emul_shared_lock); + em->shared->refs++; + EMUL_SHARED_WUNLOCK(&emul_shared_lock); + } else { + /* + * handled earlier to avoid malloc(M_WAITOK) with + * rwlock held + */ + } + + EMUL_SHARED_WLOCK(&emul_shared_lock); + LIST_INSERT_HEAD(&em->shared->threads, em, threads); + EMUL_SHARED_WUNLOCK(&emul_shared_lock); + + p = pfind(child); + KASSERT(p != NULL, ("process not found in proc_init\n")); + p->p_emuldata = em; + PROC_UNLOCK(p); + } else + EMUL_UNLOCK(&emul_lock); + + LIN_SDT_PROBE0(emul, proc_init, return); + return (0); +} + +void +linux_proc_exit(void *arg __unused, struct proc *p) +{ + struct linux_emuldata *em; + int error, shared_flags, shared_xstat; + struct thread *td = FIRST_THREAD_IN_PROC(p); + int *child_clear_tid; + struct proc *q, *nq; + + if (__predict_true(p->p_sysent != &elf_linux_sysvec)) + return; + + LIN_SDT_PROBE1(emul, proc_exit, entry, p); + + release_futexes(p); + + /* find the emuldata */ + em = em_find(p, EMUL_DOLOCK); + + KASSERT(em != NULL, ("proc_exit: emuldata not found.\n")); + + /* reparent all procs that are not a thread leader to initproc */ + if (em->shared->group_pid != p->p_pid) { + LIN_SDT_PROBE3(emul, proc_exit, reparent, + em->shared->group_pid, p->p_pid, p); + + child_clear_tid = em->child_clear_tid; + EMUL_UNLOCK(&emul_lock); + sx_xlock(&proctree_lock); + wakeup(initproc); + PROC_LOCK(p); + proc_reparent(p, initproc); + p->p_sigparent = SIGCHLD; + PROC_UNLOCK(p); + sx_xunlock(&proctree_lock); + } else { + child_clear_tid = em->child_clear_tid; + EMUL_UNLOCK(&emul_lock); + } + + EMUL_SHARED_WLOCK(&emul_shared_lock); + shared_flags = em->shared->flags; + shared_xstat = em->shared->xstat; + LIST_REMOVE(em, threads); + + em->shared->refs--; + if (em->shared->refs == 0) { + EMUL_SHARED_WUNLOCK(&emul_shared_lock); + free(em->shared, M_LINUX); + } else + EMUL_SHARED_WUNLOCK(&emul_shared_lock); + + if ((shared_flags & EMUL_SHARED_HASXSTAT) != 0) + p->p_xstat = shared_xstat; + + if (child_clear_tid != NULL) { + struct linux_sys_futex_args cup; + int null = 0; + + error = copyout(&null, child_clear_tid, sizeof(null)); + if (error) { + LIN_SDT_PROBE1(emul, proc_exit, + child_clear_tid_error, error); + + free(em, M_LINUX); + + LIN_SDT_PROBE0(emul, proc_exit, return); + return; + } + + /* futexes stuff */ + cup.uaddr = child_clear_tid; + cup.op = LINUX_FUTEX_WAKE; + cup.val = 0x7fffffff; /* Awake everyone */ + cup.timeout = NULL; + cup.uaddr2 = NULL; + cup.val3 = 0; + error = linux_sys_futex(FIRST_THREAD_IN_PROC(p), &cup); + /* + * this cannot happen at the moment and if this happens it + * probably means there is a user space bug + */ + if (error) { + LIN_SDT_PROBE0(emul, proc_exit, futex_failed); + printf(LMSG("futex stuff in proc_exit failed.\n")); + } + } + + /* clean the stuff up */ + free(em, M_LINUX); + + /* this is a little weird but rewritten from exit1() */ + sx_xlock(&proctree_lock); + q = LIST_FIRST(&p->p_children); + for (; q != NULL; q = nq) { + nq = LIST_NEXT(q, p_sibling); + if (q->p_flag & P_WEXIT) + continue; + if (__predict_false(q->p_sysent != &elf_linux_sysvec)) + continue; + em = em_find(q, EMUL_DOLOCK); + KASSERT(em != NULL, ("linux_reparent: emuldata not found: %i\n", q->p_pid)); + PROC_LOCK(q); + if ((q->p_flag & P_WEXIT) == 0 && em->pdeath_signal != 0) { + kern_psignal(q, em->pdeath_signal); + } + PROC_UNLOCK(q); + EMUL_UNLOCK(&emul_lock); + } + sx_xunlock(&proctree_lock); + + LIN_SDT_PROBE0(emul, proc_exit, return); +} + +/* + * This is used in a case of transition from FreeBSD binary execing to linux binary + * in this case we create linux emuldata proc entry with the pid of the currently running + * process. + */ +void +linux_proc_exec(void *arg __unused, struct proc *p, struct image_params *imgp) +{ + if (__predict_false(imgp->sysent == &elf_linux_sysvec)) { + LIN_SDT_PROBE2(emul, proc_exec, entry, p, imgp); + } + if (__predict_false(imgp->sysent == &elf_linux_sysvec + && p->p_sysent != &elf_linux_sysvec)) + linux_proc_init(FIRST_THREAD_IN_PROC(p), p->p_pid, 0); + if (__predict_false((p->p_sysent->sv_flags & SV_ABI_MASK) == + SV_ABI_LINUX)) + /* Kill threads regardless of imgp->sysent value */ + linux_kill_threads(FIRST_THREAD_IN_PROC(p), SIGKILL); + if (__predict_false(imgp->sysent != &elf_linux_sysvec + && p->p_sysent == &elf_linux_sysvec)) { + struct linux_emuldata *em; + + /* + * XXX:There's a race because here we assign p->p_emuldata NULL + * but the process is still counted as linux one for a short + * time so some other process might reference it and try to + * access its p->p_emuldata and panicing on a NULL reference. + */ + em = em_find(p, EMUL_DONTLOCK); + + KASSERT(em != NULL, ("proc_exec: emuldata not found.\n")); + + EMUL_SHARED_WLOCK(&emul_shared_lock); + LIST_REMOVE(em, threads); + + PROC_LOCK(p); + p->p_emuldata = NULL; + PROC_UNLOCK(p); + + em->shared->refs--; + if (em->shared->refs == 0) { + EMUL_SHARED_WUNLOCK(&emul_shared_lock); + free(em->shared, M_LINUX); + } else + EMUL_SHARED_WUNLOCK(&emul_shared_lock); + + free(em, M_LINUX); + } + + if (__predict_false(imgp->sysent == &elf_linux_sysvec)) { + LIN_SDT_PROBE0(emul, proc_exec, return); + } +} + +void +linux_schedtail(struct thread *td) +{ + struct linux_emuldata *em; + struct proc *p; + int error = 0; + int *child_set_tid; + + p = td->td_proc; + + LIN_SDT_PROBE1(emul, linux_schedtail, entry, p); + + /* find the emuldata */ + em = em_find(p, EMUL_DOLOCK); + + KASSERT(em != NULL, ("linux_schedtail: emuldata not found.\n")); + child_set_tid = em->child_set_tid; + EMUL_UNLOCK(&emul_lock); + + if (child_set_tid != NULL) { + error = copyout(&p->p_pid, (int *)child_set_tid, + sizeof(p->p_pid)); + + if (error != 0) { + LIN_SDT_PROBE1(emul, linux_schedtail, copyout_error, + error); + } + } + + LIN_SDT_PROBE0(emul, linux_schedtail, return); + + return; +} + +int +linux_set_tid_address(struct thread *td, struct linux_set_tid_address_args *args) +{ + struct linux_emuldata *em; + + LIN_SDT_PROBE1(emul, linux_set_tid_address, entry, args->tidptr); + + /* find the emuldata */ + em = em_find(td->td_proc, EMUL_DOLOCK); + + KASSERT(em != NULL, ("set_tid_address: emuldata not found.\n")); + + em->child_clear_tid = args->tidptr; + td->td_retval[0] = td->td_proc->p_pid; + + EMUL_UNLOCK(&emul_lock); + + LIN_SDT_PROBE0(emul, linux_set_tid_address, return); + return 0; +} + +void +linux_kill_threads(struct thread *td, int sig) +{ + struct linux_emuldata *em, *td_em, *tmp_em; + struct proc *sp; + + LIN_SDT_PROBE2(emul, linux_kill_threads, entry, td, sig); + + td_em = em_find(td->td_proc, EMUL_DONTLOCK); + + KASSERT(td_em != NULL, ("linux_kill_threads: emuldata not found.\n")); + + EMUL_SHARED_RLOCK(&emul_shared_lock); + LIST_FOREACH_SAFE(em, &td_em->shared->threads, threads, tmp_em) { + if (em->pid == td_em->pid) + continue; + + sp = pfind(em->pid); + if ((sp->p_flag & P_WEXIT) == 0) + kern_psignal(sp, sig); + PROC_UNLOCK(sp); + + LIN_SDT_PROBE1(emul, linux_kill_threads, kill, em->pid); + } + EMUL_SHARED_RUNLOCK(&emul_shared_lock); + + LIN_SDT_PROBE0(emul, linux_kill_threads, return); +} |
