If the access counts were not increased and decreased in equal numbers by
gvinum consumers, the read access count would be inconsistent with the write
access count. Instead, modify the read access count with the write access
count directly to prevent any inconsistencies.
Approved by: re (kib)
The system hostname is now stored in prison0, and the global variable
"hostname" has been removed, as has the hostname_mtx mutex. Jails may
have their own host information, or they may inherit it from the
parent/system. The proper way to read the hostname is via
getcredhostname(), which will copy either the hostname associated with
the passed cred, or the system hostname if you pass NULL. The system
hostname can still be accessed directly (and without locking) at
prison0.pr_host, but that should be avoided where possible.
The "similar information" referred to is domainname, hostid, and
hostuuid, which have also become prison parameters and had their
associated global variables removed.
Approved by: bz (mentor)
This is necessary for two reasons:
1) In order to avoid collisions with the use of a BIOs flags set by a consumer
or a provider
2) Because GV_BIO_DONE was used to mark a BIO as done, not enough flags was
available, so the consumer flags of a BIO had to be misused in order to
support enough flags. The new queue makes it possible to recycle the
GV_BIO_DONE flag into GV_BIO_GROW.
As a consequence, gvinum will now work with any other GEOM class under it or
on top of it.
- Use bio_pflags for storing internal flags on downgoing BIOs, as the requests
appear to come from a consumer of a gvinum volume. Use bio_cflags only for
cloned BIOs.
- Move gv_post_bio to be used internally for maintenance requests.
- Remove some cases where flags where set without need.
PR: kern/133604
as they do not really relate and to prepare for an additional queue to be
covered by the BIO queue mutex.
- Implement wrappers for fetching the next element from the event queue as well
as for putting a new element into the BIO queue.
as the renaming only changes internal gvinum names and will not alter the geom
topology.
- The topology lock was not held when calling g_wither_geom after renaming.
The work have been under testing and fixing since then, and it is mature enough
to be put into HEAD for further testing.
A lot have changed in this time, and here are the most important:
- Gvinum now uses one single workerthread instead of one thread for each
volume and each plex. The reason for this is that the previous scheme was
very complex, and was the cause of many of the bugs discovered in gvinum.
Instead, gvinum now uses one worker thread with an event queue, quite
similar to what used in gmirror.
- The rebuild/grow/initialize/parity check routines no longer runs in
separate threads, but are run as regular I/O requests with special flags.
This made it easier to support mounted growing and parity rebuild.
- Support for growing striped and raid5-plexes, meaning that one can extend the
volumes for these plex types in addition to the concat type. Also works while
the volume is mounted.
- Implementation of many of the missing commands from the old vinum:
attach/detach, start (was partially implemented), stop (was partially
implemented), concat, mirror, stripe, raid5 (shortcuts for creating volumes
with one plex of these organizations).
- The parity check and rebuild no longer goes between userland/kernel, meaning
that the gvinum command will not stay and wait forever for the rebuild to
finish. You can instead watch the status with the list command.
- Many problems with gvinum have been reported since 5.x, and some has been hard
to fix due to the complicated architecture. Hopefully, it should be more
stable and better handle edge cases that previously made gvinum crash.
- Failed drives no longer disappears entirely, but now leave behind a dummy
drive that makes sure the original state is not forgotten in case the system
is rebooted between drive failures/swaps.
- Update manpage to reflect new commands and extend it with some examples.
Sponsored by: Google Summer of Code 2007
Mentored by: le
Tested by: Rick C. Petty <rick-freebsd2008 -at- kiwi-computer.com>
plex. If the plex is a raid5 plex, and is being written to, parity data might
have to be read from the underlying disks, requiring them to be opened for
reading as well as writing.
MFC after: 1 week
practice, but it is a good programming practice nontheless and it allows the
kernel to not depend on userland correctness.
Found with: Coverity Prevent(tm)
CID: 655-659, 664-667
the gvinum header in fields of fixed size and in a big endian byte order
rather than the size and byte order of the actual platform.
Note that the change is backwards compatible with the old gvinum configuration
format, but will save the configuration in the new format when the 'saveconfig'
command is executed.
Submitted by: Rick C. Petty <rick-freebsd -at- kiwi-computer.com>
virtualization work done by Marko Zec (zec@).
This is the first in a series of commits over the course
of the next few weeks.
Mark all uses of global variables to be virtualized
with a V_ prefix.
Use macros to map them back to their global names for
now, so this is a NOP change only.
We hope to have caught at least 85-90% of what is needed
so we do not invalidate a lot of outstanding patches again.
Obtained from: //depot/projects/vimage-commit2/...
Reviewed by: brooks, des, ed, mav, julian,
jamie, kris, rwatson, zec, ...
(various people I forgot, different versions)
md5 (with a bit of help)
Sponsored by: NLnet Foundation, The FreeBSD Foundation
X-MFC after: never
V_Commit_Message_Reviewed_By: more people than the patch
to global hostname and domainname variables. Where necessary, copy
to or from a stack-local buffer before performing copyin() or
copyout(). A few uses, such as in cd9660 and daemon_saver, remain
under-synchronized and will require further updates.
Correct a bug in which a failed copyin() of domainname would leave
domainname potentially corrupted.
MFC after: 3 weeks
to kproc_xxx as they actually make whole processes.
Thos makes way for us to add REAL kthread_create() and friends
that actually make theads. it turns out that most of these
calls actually end up being moved back to the thread version
when it's added. but we need to make this cosmetic change first.
I'd LOVE to do this rename in 7.0 so that we can eventually MFC the
new kthread_xxx() calls.
o The only indication of error condition is NULL value returned by
the function;
o value pointed to by error argument is undefined in the case when
operation completes successfully.
Discussed with: phk
the geom creation to a seperate init function and ignore the tasting.
The config is now parsed only in the vinumdrive geom, which hopefully
fixes the problem, that the drive class tasted before the vinum class
had a chance, for good.
Also restore the behaviour that the module can be loaded at boot time
and on a running system.
Don't allocate potentially large variables on the stack.
Check strsep() return values when the string comes from userland.
Shorten variable names for lucidity's sake.
most of the stuff:
Pointed out by: njl@
Add functions to rename objects and to move a subdisk from one drive
to another.
Obtained from: Chris Jones <chris.jones@ualberta.ca>
Sponsored by: Google Summer of Code 2005
MFC in: 1 week
This way, the VINUMDRIVE class is loaded before the VINUM class,
but since geom does the tasting for newly arrived classes
last-in-first-out, the VINUM class tastes first.
This removes the need to call gv_parse_config() in the drive
taste path.
When a drive is newly created, it's state is initially set to 'down',
so it won't allow saving the config to it (thus it will never know of
itself being created). Work around this by adding a new flag, that's
also checked when saving the config to a drive.
post an event to the geom event queue that will take care of it,
letting outstanding bios finish, and closing the consumers.
Plus some cosmetic clean ups.
