/* ARGSUSED */
int
mfs_start(struct mount *mp, int flags)
{
struct vnode *vp;
struct mfsnode *mfsp;
struct proc *p;
struct buf *bp;
void *base;
int sleepreturn = 0, refcnt, error;
ksiginfoq_t kq;
/*
* Ensure that file system is still mounted when getting mfsnode.
* Add a reference to the mfsnode to prevent it disappearing in
* this routine.
*/
if ((error = vfs_busy(mp, NULL)) != 0)
return error;
vp = VFSTOUFS(mp)->um_devvp;
mfsp = VTOMFS(vp);
mutex_enter(&mfs_lock);
mfsp->mfs_refcnt++;
mutex_exit(&mfs_lock);
vfs_unbusy(mp, false, NULL);
base = mfsp->mfs_baseoff;
mutex_enter(&mfs_lock);
while (mfsp->mfs_shutdown != 1) {
while ((bp = bufq_get(mfsp->mfs_buflist)) != NULL) {
mutex_exit(&mfs_lock);
mfs_doio(bp, base);
mutex_enter(&mfs_lock);
}
/*
* If a non-ignored signal is received, try to unmount.
* If that fails, or the filesystem is already in the
* process of being unmounted, clear the signal (it has been
* "processed"), otherwise we will loop here, as tsleep
* will always return EINTR/ERESTART.
*/
if (sleepreturn != 0) {
mutex_exit(&mfs_lock);
if (dounmount(mp, 0, curlwp) != 0) {
p = curproc;
ksiginfo_queue_init(&kq);
mutex_enter(p->p_lock);
sigclearall(p, NULL, &kq);
mutex_exit(p->p_lock);
ksiginfo_queue_drain(&kq);
}
sleepreturn = 0;
mutex_enter(&mfs_lock);
continue;
}
sleepreturn = cv_wait_sig(&mfsp->mfs_cv, &mfs_lock);
}
KASSERT(bufq_peek(mfsp->mfs_buflist) == NULL);
refcnt = --mfsp->mfs_refcnt;
mutex_exit(&mfs_lock);
if (refcnt == 0) {
bufq_free(mfsp->mfs_buflist);
cv_destroy(&mfsp->mfs_cv);
kmem_free(mfsp, sizeof(*mfsp));
}
return (sleepreturn);
}
int
sigaction1(struct lwp *l, int signum, const struct sigaction *nsa,
struct sigaction *osa, const void *tramp, int vers)
{
struct proc *p;
struct sigacts *ps;
sigset_t tset;
int prop, error;
ksiginfoq_t kq;
static bool v0v1valid;
if (signum <= 0 || signum >= NSIG)
return EINVAL;
p = l->l_proc;
error = 0;
ksiginfo_queue_init(&kq);
/*
* Trampoline ABI version 0 is reserved for the legacy kernel
* provided on-stack trampoline. Conversely, if we are using a
* non-0 ABI version, we must have a trampoline. Only validate the
* vers if a new sigaction was supplied and there was an actual
* handler specified (not SIG_IGN or SIG_DFL), which don't require
* a trampoline. Emulations use legacy kernel trampolines with
* version 0, alternatively check for that too.
*
* If version < 2, we try to autoload the compat module. Note
* that we interlock with the unload check in compat_modcmd()
* using kernconfig_lock. If the autoload fails, we don't try it
* again for this process.
*/
if (nsa != NULL && nsa->sa_handler != SIG_IGN
&& nsa->sa_handler != SIG_DFL) {
if (__predict_false(vers < 2)) {
if (p->p_flag & PK_32)
v0v1valid = true;
else if ((p->p_lflag & PL_SIGCOMPAT) == 0) {
kernconfig_lock();
if (sendsig_sigcontext_vec == NULL) {
(void)module_autoload("compat",
MODULE_CLASS_ANY);
}
if (sendsig_sigcontext_vec != NULL) {
/*
* We need to remember if the
* sigcontext method may be useable,
* because libc may use it even
* if siginfo is available.
*/
v0v1valid = true;
}
mutex_enter(proc_lock);
/*
* Prevent unload of compat module while
* this process remains.
*/
p->p_lflag |= PL_SIGCOMPAT;
mutex_exit(proc_lock);
kernconfig_unlock();
}
}
switch (vers) {
case 0:
/* sigcontext, kernel supplied trampoline. */
if (tramp != NULL || !v0v1valid) {
return EINVAL;
}
break;
case 1:
/* sigcontext, user supplied trampoline. */
if (tramp == NULL || !v0v1valid) {
return EINVAL;
}
break;
case 2:
case 3:
/* siginfo, user supplied trampoline. */
if (tramp == NULL) {
return EINVAL;
}
break;
default:
return EINVAL;
}
}
mutex_enter(p->p_lock);
ps = p->p_sigacts;
if (osa)
*osa = SIGACTION_PS(ps, signum);
if (!nsa)
goto out;
prop = sigprop[signum];
if ((nsa->sa_flags & ~SA_ALLBITS) || (prop & SA_CANTMASK)) {
error = EINVAL;
goto out;
}
SIGACTION_PS(ps, signum) = *nsa;
ps->sa_sigdesc[signum].sd_tramp = tramp;
ps->sa_sigdesc[signum].sd_vers = vers;
sigminusset(&sigcantmask, &SIGACTION_PS(ps, signum).sa_mask);
if ((prop & SA_NORESET) != 0)
SIGACTION_PS(ps, signum).sa_flags &= ~SA_RESETHAND;
if (signum == SIGCHLD) {
if (nsa->sa_flags & SA_NOCLDSTOP)
p->p_sflag |= PS_NOCLDSTOP;
else
p->p_sflag &= ~PS_NOCLDSTOP;
if (nsa->sa_flags & SA_NOCLDWAIT) {
/*
* Paranoia: since SA_NOCLDWAIT is implemented by
* reparenting the dying child to PID 1 (and trust
* it to reap the zombie), PID 1 itself is forbidden
* to set SA_NOCLDWAIT.
*/
if (p->p_pid == 1)
p->p_flag &= ~PK_NOCLDWAIT;
else
p->p_flag |= PK_NOCLDWAIT;
} else
p->p_flag &= ~PK_NOCLDWAIT;
if (nsa->sa_handler == SIG_IGN) {
/*
* Paranoia: same as above.
*/
if (p->p_pid == 1)
p->p_flag &= ~PK_CLDSIGIGN;
else
p->p_flag |= PK_CLDSIGIGN;
} else
p->p_flag &= ~PK_CLDSIGIGN;
}
if ((nsa->sa_flags & SA_NODEFER) == 0)
sigaddset(&SIGACTION_PS(ps, signum).sa_mask, signum);
else
sigdelset(&SIGACTION_PS(ps, signum).sa_mask, signum);
/*
* Set bit in p_sigctx.ps_sigignore for signals that are set to
* SIG_IGN, and for signals set to SIG_DFL where the default is to
* ignore. However, don't put SIGCONT in p_sigctx.ps_sigignore, as
* we have to restart the process.
*/
if (nsa->sa_handler == SIG_IGN ||
(nsa->sa_handler == SIG_DFL && (prop & SA_IGNORE) != 0)) {
/* Never to be seen again. */
sigemptyset(&tset);
sigaddset(&tset, signum);
sigclearall(p, &tset, &kq);
if (signum != SIGCONT) {
/* Easier in psignal */
sigaddset(&p->p_sigctx.ps_sigignore, signum);
}
sigdelset(&p->p_sigctx.ps_sigcatch, signum);
} else {
sigdelset(&p->p_sigctx.ps_sigignore, signum);
if (nsa->sa_handler == SIG_DFL)
sigdelset(&p->p_sigctx.ps_sigcatch, signum);
else
sigaddset(&p->p_sigctx.ps_sigcatch, signum);
}
/*
* Previously held signals may now have become visible. Ensure that
* we check for them before returning to userspace.
*/
if (sigispending(l, 0)) {
lwp_lock(l);
l->l_flag |= LW_PENDSIG;
lwp_unlock(l);
}
out:
mutex_exit(p->p_lock);
ksiginfo_queue_drain(&kq);
return error;
}
