Hold the reference count until the CCB is released

When a disk disappears and the periph is invalidated, any I/Os that
are pending with the controller can cause a crash when they
complete. Move to holding the softc reference count taken in dastart()
until the I/O is complete rather than only until xpt_action()
returns. (This approach was suggested by Ken Merry.) This extends
the method used in da to ada, nda, and mda.

Sponsored by: Netflix
Submitted by: Chuck Silvers
This commit is contained in:
Warner Losh 2018-05-15 22:22:10 +00:00
parent 40f242e440
commit d9a7a61b2b
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=333651
3 changed files with 14 additions and 4 deletions

View File

@ -2458,7 +2458,6 @@ adastart(struct cam_periph *periph, union ccb *start_ccb)
cam_periph_unlock(periph);
xpt_action(start_ccb);
cam_periph_lock(periph);
softc->refcount--;
/* May have more work to do, so ensure we stay scheduled */
adaschedule(periph);
@ -2856,10 +2855,13 @@ adadone(struct cam_periph *periph, union ccb *done_ccb)
* We need to call cam_iosched before we call biodone so that we
* don't measure any activity that happens in the completion
* routine, which in the case of sendfile can be quite
* extensive.
* extensive. Release the periph refcount taken in adastart()
* for each CCB.
*/
cam_iosched_bio_complete(softc->cam_iosched, bp, done_ccb);
xpt_release_ccb(done_ccb);
KASSERT(softc->refcount >= 1, ("adadone softc %p refcount %d", softc, softc->refcount));
softc->refcount--;
if (state == ADA_CCB_TRIM) {
TAILQ_HEAD(, bio) queue;
struct bio *bp1;

View File

@ -1357,7 +1357,6 @@ sddastart(struct cam_periph *periph, union ccb *start_ccb)
cam_periph_unlock(periph);
xpt_action(start_ccb);
cam_periph_lock(periph);
softc->refcount--;
/* May have more work to do, so ensure we stay scheduled */
sddaschedule(periph);
@ -1418,6 +1417,11 @@ sddadone(struct cam_periph *periph, union ccb *done_ccb)
softc->outstanding_cmds--;
xpt_release_ccb(done_ccb);
/*
* Release the periph refcount taken in mdastart() for each CCB.
*/
KASSERT(softc->refcount >= 1, ("mdadone softc %p refcount %d", softc, softc->refcount));
softc->refcount--;
biodone(bp);
}

View File

@ -990,7 +990,6 @@ ndastart(struct cam_periph *periph, union ccb *start_ccb)
cam_periph_unlock(periph);
xpt_action(start_ccb);
cam_periph_lock(periph);
softc->refcount--;
/* May have more work to do, so ensure we stay scheduled */
ndaschedule(periph);
@ -1101,6 +1100,11 @@ ndadone(struct cam_periph *periph, union ccb *done_ccb)
biodone(bp2);
}
}
/*
* Release the periph refcount taken in mdastart() for each CCB.
*/
KASSERT(softc->refcount >= 1, ("ndadone softc %p refcount %d", softc, softc->refcount));
softc->refcount--;
return;
}
case NDA_CCB_DUMP: