that the events queue is empty. In other case we're able to hit the race
where for example da0s1 is tasted by some other class, which means that
da0 is open with exclusive bit set, which means that we can't open da0
for writing if it is our component.
Reported by: Attila Nagy <bra@fsn.hu> (and somebody else sometime ago,
but I cannot find who it was)
seconds of idling, DRITY flags are removed.
- If mirror is in idle state or is not open for writing, sleep without
timeout when waiting for I/O requests.
- Don't use atomic operations, for now sysctls are protected by Giant.
- Update debugs.
- Fix for good (I hope) force-stopping mirrors and some filure cases
(e.g. the last good component dies when synchronization is in progress).
Don't use ->nstart/->nend consumer's fields, as this could be racy,
because those fields are used in g_down/g_up, use ->index consumer's
field instead for tracking number of not finished requests.
Reported by: marcel
- After 5 seconds of idle time (this should be configurable) mark all
dirty providers as clean, so when mirror is not used in 5 seconds
and there will be power failure, no synchronization on boot is needed.
Idea from: sorry, I can't find who suggested this
- When there are no ACTIVE components and no NEW components destroy whole
mirror, not only provider.
- Fix one debug to show information about I/O request, before we change
its command.
buf->b-dev.
Put a bio between the buf passed to dev_strategy() and the device driver
strategy routine in order to not clobber fields in the buf.
Assert copyright on vfs_bio.c and update copyright message to canonical
text. There is no legal difference between John Dysons two-clause
abbreviated BSD license and the canonical text.
This flag gets set whenever the thread posts an event on the GEOM
event queue, and if the flag is set when the thread is prepared
to return to userland from the kernel, g_waitidle() will be called
to make sure that the posted events have completed.
This can replace an insufficient number of g_waitidle() calls in
various other places, and has the advantage of being failsafe: Any
system call which does a VOP_OPEN()/VOP_CLOSE will now correctly
wait for any geom events it posted as part of spoils or tastes.
Assert that topology and Giant is not held in g_waitidle().
in the g_up and g_down threads. Each time a bio is propelled up and
down the stack, an event is generating showing the provider, offset,
and length, as well as thread wakeup and work status information.
providers for tasting. Before this hack, race below is possible:
SI_SUB_RAID (no not-fully-configured geoms, so don't block)
GEOM tasting (now geoms are created)
SI_SUB_MOUNT_ROOT (if root file system is placed on a mirror, it is
possible that this mirror is not fully configured yet)
There is a lot of work to do to avoid such hacks and I need a working
solution before 5.3, sorry.
Reported by: John Hay <jhay@icomtek.csir.co.za>
We have to use our own destroy_geom method, because default one, which
is a part of geom_slice is broken.
MT5 candidate.
PR: kern/72467
Submitted by: Vladimir Novoseltsev
by the time that kldload(8) returns. Satisfy that by making the GEOM
module load event -- only when the kernel is !cold -- wait until the
GEOM module init function has finished instead of returning immediately.
This is the other half of fixing md(8) (actually, "mfs" in fstab(5))
that is similar to r1.128 of src/sys/dev/md/md.c. This bug would be
why RAM disks would often fail on boot and the first call to mdconfig(8)
would probably fail.
pjd has ideas for not requiring kldload(8) to work synchronously for
control devices that could make this obsolete.
Silence on: -arch
This also adds support for bigger disks on the controller I have access to,
and maybe others if I understood the adhoc methods used on those.
Those with more PC98 bigdrive controllers it is hereby invited to add/fix
support for those in geom_pc98.c and not using #ifdef PC98 all over the place.
but it is possible:
1. Read data from good component for synchronization.
2. Write data to the same area.
3. Write synchronization data, which are now stale.
Found by: tegge (for gmirror)
