xnu-4903.221.2.tar.gz

[apple/xnu.git] / bsd / miscfs / specfs / spec_vnops.c

diff --git a/bsd/miscfs/specfs/spec_vnops.c b/bsd/miscfs/specfs/spec_vnops.c
index 6e0c09d1cf99dfb8020bb5fa70aa750995039c8b..702787a410b652e109f28b24441cb58ffcf967be 100644 (file)
--- a/bsd/miscfs/specfs/spec_vnops.c
+++ b/bsd/miscfs/specfs/spec_vnops.c
@@ -1138,7 +1138,7 @@ throttle_timer(struct _throttle_io_info_t *info)
                        ut = (uthread_t)TAILQ_FIRST(&info->throttle_uthlist[wake_level]);
                        TAILQ_REMOVE(&info->throttle_uthlist[wake_level], ut, uu_throttlelist);
                        ut->uu_on_throttlelist = THROTTLE_LEVEL_NONE;
-                       ut->uu_is_throttled = FALSE;
+                       ut->uu_is_throttled = false;
 
                        wake_address = (caddr_t)&ut->uu_on_throttlelist;
                }
@@ -1156,7 +1156,7 @@ throttle_timer(struct _throttle_io_info_t *info)
 
                        TAILQ_REMOVE(&info->throttle_uthlist[level], ut, uu_throttlelist);
                        ut->uu_on_throttlelist = THROTTLE_LEVEL_NONE;
-                       ut->uu_is_throttled = FALSE;
+                       ut->uu_is_throttled = false;
 
                        wakeup(&ut->uu_on_throttlelist);
                }
@@ -1335,13 +1335,12 @@ throttle_init(void)
 }
 
 void
-sys_override_io_throttle(int flag)
+sys_override_io_throttle(boolean_t enable_override)
 {
-       if (flag == THROTTLE_IO_ENABLE)
-               lowpri_throttle_enabled = 1;
-
-       if (flag == THROTTLE_IO_DISABLE)
+       if (enable_override)
                lowpri_throttle_enabled = 0;
+       else
+               lowpri_throttle_enabled = 1;
 }
 
 int rethrottle_wakeups = 0;
@@ -1382,19 +1381,19 @@ rethrottle_thread(uthread_t ut)
        boolean_t s = ml_set_interrupts_enabled(FALSE);
        lck_spin_lock(&ut->uu_rethrottle_lock);
 
-       if (ut->uu_is_throttled == FALSE)
-               ut->uu_was_rethrottled = TRUE;
+       if (!ut->uu_is_throttled)
+               ut->uu_was_rethrottled = true;
        else {
                int my_new_level = throttle_get_thread_throttle_level(ut);
 
                if (my_new_level != ut->uu_on_throttlelist) {
                        /*
                         * ut is currently blocked (as indicated by
-                        * ut->uu_is_throttled == TRUE)
+                        * ut->uu_is_throttled == true)
                         * and we're changing it's throttle level, so
                         * we need to wake it up.
                         */
-                       ut->uu_is_throttled = FALSE;
+                       ut->uu_is_throttled = false;
                        wakeup(&ut->uu_on_throttlelist);
 
                        rethrottle_wakeups++;
@@ -1622,7 +1621,7 @@ throttle_get_thread_throttle_level_internal(uthread_t ut, int io_tier) {
        assert(ut != NULL);
 
        /* Bootcache misses should always be throttled */
-       if (ut->uu_throttle_bc == TRUE)
+       if (ut->uu_throttle_bc)
                thread_throttle_level = THROTTLE_LEVEL_TIER3;
 
        /*
@@ -1781,7 +1780,7 @@ throttle_lowpri_io(int sleep_amount)
        info = ut->uu_throttle_info;
 
        if (info == NULL) {
-               ut->uu_throttle_bc = FALSE;
+               ut->uu_throttle_bc = false;
                ut->uu_lowpri_window = 0;
                return (0);
        }
@@ -1791,12 +1790,12 @@ throttle_lowpri_io(int sleep_amount)
        if (sleep_amount == 0)
                goto done;
 
-       if (sleep_amount == 1 && ut->uu_throttle_bc == FALSE)
+       if (sleep_amount == 1 && !ut->uu_throttle_bc)
                sleep_amount = 0;
 
        throttle_io_period_num = info->throttle_io_period_num;
 
-       ut->uu_was_rethrottled = FALSE;
+       ut->uu_was_rethrottled = false;
 
        while ( (throttle_type = throttle_io_will_be_throttled_internal(info, &mylevel, &throttling_level)) ) {
 
@@ -1836,7 +1835,7 @@ throttle_lowpri_io(int sleep_amount)
                 * this is the critical section w/r to our interaction
                 * with "rethrottle_thread"
                 */
-               if (ut->uu_was_rethrottled == TRUE) {
+               if (ut->uu_was_rethrottled) {
 
                        lck_spin_unlock(&ut->uu_rethrottle_lock);
                        ml_set_interrupts_enabled(s);
@@ -1844,7 +1843,7 @@ throttle_lowpri_io(int sleep_amount)
 
                        KERNEL_DEBUG_CONSTANT((FSDBG_CODE(DBG_FSRW, 103)), thread_tid(ut->uu_thread), ut->uu_on_throttlelist, 0, 0, 0);
 
-                       ut->uu_was_rethrottled = FALSE;
+                       ut->uu_was_rethrottled = false;
                        continue;
                }
                KERNEL_DEBUG_CONSTANT((FSDBG_CODE(DBG_THROTTLE, PROCESS_THROTTLED)) | DBG_FUNC_NONE,
@@ -1859,7 +1858,7 @@ throttle_lowpri_io(int sleep_amount)
 
                assert_wait((caddr_t)&ut->uu_on_throttlelist, THREAD_UNINT);
 
-               ut->uu_is_throttled = TRUE;
+               ut->uu_is_throttled = true;
                lck_spin_unlock(&ut->uu_rethrottle_lock);
                ml_set_interrupts_enabled(s);
 
@@ -1869,8 +1868,8 @@ throttle_lowpri_io(int sleep_amount)
 
                ut->uu_wmesg = NULL;
 
-               ut->uu_is_throttled = FALSE;
-               ut->uu_was_rethrottled = FALSE;
+               ut->uu_is_throttled = false;
+               ut->uu_was_rethrottled = false;
 
                lck_mtx_lock(&info->throttle_lock);
 
@@ -1904,7 +1903,7 @@ done:
        }
 
        ut->uu_throttle_info = NULL;
-       ut->uu_throttle_bc = FALSE;
+       ut->uu_throttle_bc = false;
        ut->uu_lowpri_window = 0;
 
        throttle_info_rel(info);
@@ -1942,7 +1941,7 @@ void throttle_info_reset_window(uthread_t ut)
 
                ut->uu_throttle_info = NULL;
                ut->uu_lowpri_window = 0;
-               ut->uu_throttle_bc = FALSE;
+               ut->uu_throttle_bc = false;
        }
 }
 
@@ -2349,7 +2348,7 @@ spec_strategy(struct vnop_strategy_args *ap)
 
        if (kdebug_enable) {
                KERNEL_DEBUG_CONSTANT_IST(KDEBUG_COMMON, FSDBG_CODE(DBG_DKRW, code) | DBG_FUNC_NONE,
-                                         buf_kernel_addrperm_addr(bp), bdev, (int)buf_blkno(bp), buf_count(bp), 0);
+                                         buf_kernel_addrperm_addr(bp), bdev, buf_blkno(bp), buf_count(bp), 0);
         }
 
        thread_update_io_stats(current_thread(), buf_count(bp), code);
@@ -2650,7 +2649,7 @@ static void filt_specdetach(struct knote *kn);
 static int filt_specevent(struct knote *kn, long hint);
 static int filt_spectouch(struct knote *kn, struct kevent_internal_s *kev);
 static int filt_specprocess(struct knote *kn, struct filt_process_s *data, struct kevent_internal_s *kev);
-static unsigned filt_specpeek(struct knote *kn);
+static int filt_specpeek(struct knote *kn);
 
 SECURITY_READ_ONLY_EARLY(struct filterops) spec_filtops = {
        .f_isfd    = 1,
@@ -2719,6 +2718,14 @@ spec_knote_select_and_link(struct knote *kn)
         */
        old_wqs = uth->uu_wqset;
        uth->uu_wqset = &(knote_get_kq(kn)->kq_wqs);
+
+       /*
+        * Be sure that the waitq set is linked
+        * before calling select to avoid possible
+        * allocation under spinlocks.
+        */
+       waitq_set_lazy_init_link(uth->uu_wqset);
+
        /*
         * Now these are the laws of VNOP_SELECT, as old and as true as the sky,
         * And the device that shall keep it may prosper, but the device that shall
@@ -2877,8 +2884,6 @@ filt_spectouch(struct knote *kn, struct kevent_internal_s *kev)
 {
        kn->kn_sdata = kev->data;
        kn->kn_sfflags = kev->fflags;
-       if ((kn->kn_status & KN_UDATA_SPECIFIC) == 0)
-               kn->kn_udata = kev->udata;
 
        if (kev->flags & EV_ENABLE) {
                return spec_knote_select_and_link(kn);
@@ -2902,8 +2907,6 @@ filt_specprocess(struct knote *kn, struct filt_process_s *data, struct kevent_in
        ctx = vfs_context_current();
        vp = (vnode_t)kn->kn_fp->f_fglob->fg_data;
 
-       /* FIXME JMM - locking against touches? */
-
        error = vnode_getwithvid(vp, kn->kn_hookid);
        if (error != 0) {
                kn->kn_flags |= (EV_EOF | EV_ONESHOT);
@@ -2930,7 +2933,7 @@ filt_specprocess(struct knote *kn, struct filt_process_s *data, struct kevent_in
        return res;
 }
 
-static unsigned
+static int
 filt_specpeek(struct knote *kn)
 {
        int selres = 0;
@@ -2938,6 +2941,6 @@ filt_specpeek(struct knote *kn)
        selres = spec_knote_select_and_link(kn);
        filt_spec_common(kn, selres);
 
-       return kn->kn_data;
+       return kn->kn_data != 0;
 }