/*
* Variant of page_unlock() specifically for the page freelist
* code. The mere existence of this code is a vile hack that
* has resulted due to the backwards locking order of the page
* freelist manager; please don't call it.
*/
void
page_unlock_nocapture(page_t *pp)
{
kmutex_t *pse = PAGE_SE_MUTEX(pp);
selock_t old;
mutex_enter(pse);
old = pp->p_selock;
if ((old & ~SE_EWANTED) == SE_READER) {
pp->p_selock = old & ~SE_READER;
if (CV_HAS_WAITERS(&pp->p_cv))
cv_broadcast(&pp->p_cv);
} else if ((old & ~SE_EWANTED) == SE_DELETED) {
panic("page_unlock_nocapture: page %p is deleted", pp);
} else if (old < 0) {
THREAD_KPRI_RELEASE();
pp->p_selock &= SE_EWANTED;
if (CV_HAS_WAITERS(&pp->p_cv))
cv_broadcast(&pp->p_cv);
} else if ((old & ~SE_EWANTED) > SE_READER) {
pp->p_selock = old - SE_READER;
} else {
panic("page_unlock_nocapture: page %p is not locked", pp);
}
mutex_exit(pse);
}
/*ARGSUSED*/
int64_t
loadable_syscall(
long a0, long a1, long a2, long a3,
long a4, long a5, long a6, long a7)
{
klwp_t *lwp = ttolwp(curthread);
int64_t rval;
struct sysent *callp;
struct sysent *se = LWP_GETSYSENT(lwp);
krwlock_t *module_lock;
int code, error = 0;
int64_t (*sy_call)();
code = curthread->t_sysnum;
callp = se + code;
/*
* Try to autoload the system call if necessary
*/
module_lock = lock_syscall(se, code);
THREAD_KPRI_RELEASE(); /* drop priority given by rw_enter */
/*
* we've locked either the loaded syscall or nosys
*/
if (lwp_getdatamodel(lwp) == DATAMODEL_NATIVE) {
#if defined(_LP64)
if (callp->sy_flags & SE_ARGC) {
sy_call = (int64_t (*)())callp->sy_call;
rval = (*sy_call)(a0, a1, a2, a3, a4, a5);
} else
rval = syscall_ap();
} else {
#endif
/*
* Now that it's loaded, make sure enough args were copied.
*/
if (COPYIN_ARGS32(lwptoregs(lwp), lwp->lwp_ap, callp->sy_narg))
error = EFAULT;
if (error) {
rval = set_errno(error);
} else if (callp->sy_flags & SE_ARGC) {
sy_call = (int64_t (*)())callp->sy_call;
rval = (*sy_call)(lwp->lwp_ap[0], lwp->lwp_ap[1],
lwp->lwp_ap[2], lwp->lwp_ap[3], lwp->lwp_ap[4],
lwp->lwp_ap[5]);
} else
rval = syscall_ap();
}
THREAD_KPRI_REQUEST(); /* regain priority from read lock */
rw_exit(module_lock);
return (rval);
}
/*
* lxpr_unlock()
*
* Unlock locked process
*/
void
lxpr_unlock(proc_t *p)
{
ASSERT(p->p_proc_flag & P_PR_LOCK);
ASSERT(MUTEX_HELD(&p->p_lock));
ASSERT(!MUTEX_HELD(&pidlock));
cv_signal(&pr_pid_cv[p->p_slot]);
p->p_proc_flag &= ~P_PR_LOCK;
mutex_exit(&p->p_lock);
THREAD_KPRI_RELEASE();
}
/*
* Release the page's "shared/exclusive" lock and wake up anyone
* who might be waiting for it.
*/
void
page_unlock(page_t *pp)
{
kmutex_t *pse = PAGE_SE_MUTEX(pp);
selock_t old;
mutex_enter(pse);
old = pp->p_selock;
if ((old & ~SE_EWANTED) == SE_READER) {
pp->p_selock = old & ~SE_READER;
if (CV_HAS_WAITERS(&pp->p_cv))
cv_broadcast(&pp->p_cv);
} else if ((old & ~SE_EWANTED) == SE_DELETED) {
panic("page_unlock: page %p is deleted", pp);
} else if (old < 0) {
THREAD_KPRI_RELEASE();
pp->p_selock &= SE_EWANTED;
if (CV_HAS_WAITERS(&pp->p_cv))
cv_broadcast(&pp->p_cv);
} else if ((old & ~SE_EWANTED) > SE_READER) {
pp->p_selock = old - SE_READER;
} else {
panic("page_unlock: page %p is not locked", pp);
}
if (pp->p_selock == 0) {
/*
* If the T_CAPTURING bit is set, that means that we should
* not try and capture the page again as we could recurse
* which could lead to a stack overflow panic or spending a
* relatively long time in the kernel making no progress.
*/
if ((pp->p_toxic & PR_CAPTURE) &&
!(curthread->t_flag & T_CAPTURING) &&
!PP_RETIRED(pp)) {
THREAD_KPRI_REQUEST();
pp->p_selock = SE_WRITER;
mutex_exit(pse);
page_unlock_capture(pp);
} else {
mutex_exit(pse);
}
} else {
mutex_exit(pse);
}
}
void
page_lock_delete(page_t *pp)
{
kmutex_t *pse = PAGE_SE_MUTEX(pp);
ASSERT(PAGE_EXCL(pp));
ASSERT(pp->p_vnode == NULL);
ASSERT(pp->p_offset == (u_offset_t)-1);
ASSERT(!PP_ISFREE(pp));
mutex_enter(pse);
THREAD_KPRI_RELEASE();
pp->p_selock = SE_DELETED;
if (CV_HAS_WAITERS(&pp->p_cv))
cv_broadcast(&pp->p_cv);
mutex_exit(pse);
}
/*
* Downgrade the "exclusive" lock on the page to a "shared" lock
* while holding the mutex protecting this page's p_selock field.
*/
void
page_downgrade(page_t *pp)
{
kmutex_t *pse = PAGE_SE_MUTEX(pp);
int excl_waiting;
ASSERT((pp->p_selock & ~SE_EWANTED) != SE_DELETED);
ASSERT(PAGE_EXCL(pp));
mutex_enter(pse);
excl_waiting = pp->p_selock & SE_EWANTED;
THREAD_KPRI_RELEASE();
pp->p_selock = SE_READER | excl_waiting;
if (CV_HAS_WAITERS(&pp->p_cv))
cv_broadcast(&pp->p_cv);
mutex_exit(pse);
}
/*ARGSUSED*/
int64_t
loadable_syscall(
long a0, long a1, long a2, long a3,
long a4, long a5, long a6, long a7)
{
int64_t rval;
struct sysent *callp;
struct sysent *se = LWP_GETSYSENT(ttolwp(curthread));
krwlock_t *module_lock;
int code;
code = curthread->t_sysnum;
callp = se + code;
/*
* Try to autoload the system call if necessary.
*/
module_lock = lock_syscall(se, code);
THREAD_KPRI_RELEASE(); /* drop priority given by rw_enter */
/*
* we've locked either the loaded syscall or nosys
*/
if (callp->sy_flags & SE_ARGC) {
int64_t (*sy_call)();
sy_call = (int64_t (*)())callp->sy_call;
rval = (*sy_call)(a0, a1, a2, a3, a4, a5);
} else {
rval = syscall_ap();
}
THREAD_KPRI_REQUEST(); /* regain priority from read lock */
rw_exit(module_lock);
return (rval);
}
