Commit Graph

140 Commits

Author SHA1 Message Date
Alexander Motin
4a3760bae6 Remove compatibility shims for legacy ATA device names.
We got new ATA stack in FreeBSD 8.x, switched to it at 9.x, completely
removed old stack at 10.x, so at 11.x it is time to remove compat shims.
2015-10-11 13:01:51 +00:00
Conrad Meyer
b4d7290796 geom_dev: Use kenv 'dumpdev' in the same way as rc/etc.d/dumpon
Skip a /dev/ prefix, if one is present, when checking for matching
device names for dump.

Suggested by:	avg
Reviewed by:	markj
Sponsored by:	EMC / Isilon Storage Division
Differential Revision:	https://reviews.freebsd.org/D3725
2015-09-23 21:08:52 +00:00
Edward Tomasz Napierala
72800098bf Fix panic triggered by code like this:
open("/dev/md0", O_EXEC);

Discussed with:	kib@, mav@
MFC after:	1 month
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D3051
2015-08-04 10:40:08 +00:00
Edward Tomasz Napierala
d6cc35b287 Fix panic that would happen on forcibly unmounting devfs (note that
as it is now, devfs ignores MNT_FORCE anyway, so it needs to be modified
to trigger the panic) with consumers still opened.

Note that this still results in a leak of r/w/e counters.  It seems
to be harmless, though.  If anyone knows a better way to approach
this - please tell.

Discussed with:	kib@, mav@
MFC after:	1 month
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D3050
2015-08-03 16:35:18 +00:00
Alexander Motin
0ada3afc25 Remove sleeps from geom_up thread on device destruction.
MFC after:	3 days.
2015-04-09 13:09:05 +00:00
Edward Tomasz Napierala
01de1a0650 Add devd(8) notifications for creation and destruction of GEOM devices.
Differential Revision:	https://reviews.freebsd.org/D1211
MFC after:	1 month
Sponsored by:	The FreeBSD Foundation
2015-01-14 11:15:57 +00:00
Pawel Jakub Dawidek
5ebb15b942 Add missing privilege check when setting the dump device. Before that change it
was possible for a regular user to setup the dump device if he had write access
to the given device. In theory it is a security issue as user might get access
to kernel's memory after provoking kernel crash, but in practise it is not
recommended to give regular users direct access to storage devices.

Rework the code so that we do privileges check within the set_dumper() function
to avoid similar problems in the future.

Discussed with:	secteam
2014-11-11 04:48:09 +00:00
Alexander Motin
c3e7ba3e6d Add to CTL support for logical block provisioning threshold notifications.
For ZVOL-backed LUNs this allows to inform initiators if storage's used or
available spaces get above/below the configured thresholds.

MFC after:	2 weeks
Sponsored by:	iXsystems, Inc.
2014-11-06 00:48:36 +00:00
Davide Italiano
2be111bf7d Follow up to r225617. In order to maximize the re-usability of kernel code
in userland rename in-kernel getenv()/setenv() to kern_setenv()/kern_getenv().
This fixes a namespace collision with libc symbols.

Submitted by:   kmacy
Tested by:      make universe
2014-10-16 18:04:43 +00:00
Andrey V. Elsukov
0478dc0c16 Add an ability to set dumpdev via loader(8) tunable.
MFC after:	3 weeks
2014-10-08 12:18:16 +00:00
Hiroki Sato
d17183901f Fix a bug in r272297 which prevented dumpdev from setting.
!u is not equivalent to (u != 0).
2014-10-03 04:13:25 +00:00
Pawel Jakub Dawidek
227f68edbb Be prepared that set_dumper() might fail even when resetting it or prefix
the call with (void) to document that we intentionally ignore the return
value - no way to handle an error in case of device disappearing.
2014-09-30 12:00:50 +00:00
Pawel Jakub Dawidek
7f5b50719b Style fixes. 2014-09-30 11:51:32 +00:00
Scott Long
274919e965 Deal explicitly with possible failures of make_dev_alias_p() in GEOM.
Submitted by:   Mariusz Zaborski <oshogbo@FreeBSD.org>
MFC after:      3 days
2014-08-18 19:27:47 +00:00
Alexander Motin
2634da8cd5 Fix bug introduced at r256607. We have to recalculate bp_resid here since
sizes of original and completed requests may differ due to end of media.

Bisected by:	pho
2013-12-12 08:23:28 +00:00
Alexander Motin
40ea77a036 Merge GEOM direct dispatch changes from the projects/camlock branch.
When safety requirements are met, it allows to avoid passing I/O requests
to GEOM g_up/g_down thread, executing them directly in the caller context.
That allows to avoid CPU bottlenecks in g_up/g_down threads, plus avoid
several context switches per I/O.

The defined now safety requirements are:
 - caller should not hold any locks and should be reenterable;
 - callee should not depend on GEOM dual-threaded concurency semantics;
 - on the way down, if request is unmapped while callee doesn't support it,
   the context should be sleepable;
 - kernel thread stack usage should be below 50%.

To keep compatibility with GEOM classes not meeting above requirements
new provider and consumer flags added:
 - G_CF_DIRECT_SEND -- consumer code meets caller requirements (request);
 - G_CF_DIRECT_RECEIVE -- consumer code meets callee requirements (done);
 - G_PF_DIRECT_SEND -- provider code meets caller requirements (done);
 - G_PF_DIRECT_RECEIVE -- provider code meets callee requirements (request).
Capable GEOM class can set them, allowing direct dispatch in cases where
it is safe.  If any of requirements are not met, request is queued to
g_up or g_down thread same as before.

Such GEOM classes were reviewed and updated to support direct dispatch:
CONCAT, DEV, DISK, GATE, MD, MIRROR, MULTIPATH, NOP, PART, RAID, STRIPE,
VFS, ZERO, ZFS::VDEV, ZFS::ZVOL, all classes based on g_slice KPI (LABEL,
MAP, FLASHMAP, etc).

To declare direct completion capability disk(9) KPI got new flag equivalent
to G_PF_DIRECT_SEND -- DISKFLAG_DIRECT_COMPLETION.  da(4) and ada(4) disk
drivers got it set now thanks to earlier CAM locking work.

This change more then twice increases peak block storage performance on
systems with manu CPUs, together with earlier CAM locking changes reaching
more then 1 million IOPS (512 byte raw reads from 16 SATA SSDs on 4 HBAs to
256 user-level threads).

Sponsored by:	iXsystems, Inc.
MFC after:	2 months
2013-10-22 08:22:19 +00:00
Alexander Motin
21d0712c33 MFprojects/camlock r256371:
Fix passing uninitialized bio_resid argument to g_trace().
2013-10-16 09:21:40 +00:00
Kenneth D. Merry
ce625ec719 Change the way that unmapped I/O capability is advertised.
The previous method was to set the D_UNMAPPED_IO flag in the cdevsw
for the driver.  The problem with this is that in many cases (e.g.
sa(4)) there may be some instances of the driver that can handle
unmapped I/O and some that can't.  The isp(4) driver can handle
unmapped I/O, but the esp(4) driver currently cannot.  The cdevsw
is shared among all driver instances.

So instead of setting a flag on the cdevsw, set a flag on the cdev.
This allows drivers to indicate support for unmapped I/O on a
per-instance basis.

sys/conf.h:	Remove the D_UNMAPPED_IO cdevsw flag and replace it
		with an SI_UNMAPPED cdev flag.

kern_physio.c:	Look at the cdev SI_UNMAPPED flag to determine
		whether or not a particular driver can handle
		unmapped I/O.

geom_dev.c:	Set the SI_UNMAPPED flag for all GEOM cdevs.
		Since GEOM will create a temporary mapping when
		needed, setting SI_UNMAPPED unconditionally will
		work.

		Remove the D_UNMAPPED_IO flag.

nvme_ns.c:	Set the SI_UNMAPPED flag on cdevs created here
		if NVME_UNMAPPED_BIO_SUPPORT is enabled.

vfs_aio.c:	In aio_qphysio(), check the SI_UNMAPPED flag on a
		cdev instead of the D_UNMAPPED_IO flag on the cdevsw.

sys/param.h:	Bump __FreeBSD_version to 1000045 for the switch from
		setting the D_UNMAPPED_IO flag in the cdevsw to setting
		SI_UNMAPPED in the cdev.

Reviewed by:	kib, jimharris
MFC after:	1 week
Sponsored by:	Spectra Logic
2013-08-15 22:52:39 +00:00
Steven Hartland
6f926c0b82 Added a sysctl (kern.geom.dev.delete_max_sectors) to control the maximum
size of a delete request sent to the providing device performed by g_dev_ioctl.

This allows the kernel and apps via ioctl e.g. newfs -E to request large LBA
deletes which siginificantly improves performance.

Previously this was hard coded to 65536 sectors, the new default is 262144
which doubles the throughput of deletes on commonly available SSD's.

In tests on a Intel 520 120GB FW: 400i disk it improved the delete throughput
from 1.6GB/s to over 2.6GB/s on a full disk delete such as that done via
newfs -E

For some SSD's where delete time is pretty much constant, no matter what
the request, setting this to 0 will provide significantly better throughput
e.g. Samsung 840 240GB FW DXT07B0Q @ 262144 = 79G/s, @ 0 = 2259G/s

Reviewed by:	mav
Approved by:	pjd (mentor)
MFC after:	2 weeks
2013-04-26 15:43:24 +00:00
Edward Tomasz Napierala
16fac6c92a Make it possible to submit FLUSH bios through geom_dev strategy. This
is required for CTL to work with device-backed LUNs.

Reviewed by:	mav
2013-04-06 10:32:06 +00:00
Alexander Kabaev
31932fae1e Do not pass unmapped buffers to drivers that cannot handle them
In physio, check if device can handle unmapped IO and pass an
appropriately mapped buffer to the driver strategy routine. The
only driver in the tree that can handle unmapped buffers is one
exposed by GEOM, so mark it as such with the new flag in the
driver cdevsw structure.

This fixes insta-panics on hosts, running dconschat, as /dev/fwmem
is an example of the driver that makes use of physio routine, but
bypasses the g_down thread, where the buffer gets mapped normally.

Discussed with: kib (earlier version)
2013-03-26 01:17:06 +00:00
Alexander Motin
3c330aff3f Fix long known deadlock between geom dev destruction and d_close() call.
Use destroy_dev_sched_cb() to not wait for device destruction while holding
GEOM topology lock (that actually caused deadlock).  Use request counting
protected by mutex to properly wait for outstanding requests completion in
cases of device closing and geom destruction.  Unlike r227009, this code
does not block taskqueue thread for indefinite time, waiting for completion.
2013-03-24 10:14:25 +00:00
Jaakko Heinonen
02c62349c9 - Don't pass geom and provider names as format strings.
- Add __printflike() attributes.
- Remove an extra argument for the g_new_geomf() call in swapongeom_ev().

Reviewed by:	pjd
2012-11-20 12:32:18 +00:00
Alfred Perlstein
bad7e7f3dd Provide a device name in the sysctl tree for programs to query the
state of crashdump target devices.

This will be used to add a "-l" (ell) flag to dumpon(8) to list the
currently configured dumpdev.

Reviewed by:	phk
2012-11-01 17:01:05 +00:00
Ed Schouten
24d1105dde Remove unneeded G_PF_CANDELETE flag.
This flag is only used by GEOM so it can be propagated to the character
device's SI_CANDELETE. Unfortunately, SI_CANDELETE seems to do nothing.
2012-08-28 19:28:31 +00:00
Alexander Motin
3631c6382f Implement media change notification for DA and CD removable media devices.
It includes three parts:
 1) Modifications to CAM to detect media media changes and report them to
disk(9) layer. For modern SATA (and potentially UAS) devices it utilizes
Asynchronous Notification mechanism to receive events from hardware.
Active polling with TEST UNIT READY commands with 3 seconds period is used
for incapable hardware. After that both CD and DA drivers work the same way,
detecting two conditions: "NOT READY: Medium not present" after medium was
detected previously, and "UNIT ATTENTION: Not ready to ready change, medium
may have changed". First one reported to disk(9) as media removal, second
as media insert/change. To reliably receive second event new
AC_UNIT_ATTENTION async added to make UAs broadcasted to all periphs by
generic error handling code in cam_periph_error().
 2) Modifications to GEOM core to handle media remove and change events.
Media removal handled by spoiling all consumers attached to the provider.
Media change event also schedules provider retaste after spoiling to probe
new media. New flag G_CF_ORPHAN was added to consumers to reflect that
consumer is in process of destruction. It allows retaste to create new
geom instance of the same class, while previous one is still dying.
 3) Modifications to some GEOM classes: DEV -- to report media change
events to devd; VFS -- to handle spoiling same as orphan to prevent
accessing replaced media. PART class already handles spoiling alike to
orphan.

Reviewed by:	silence on geom@ and scsi@
Tested by:	avg
Sponsored by:	iXsystems, Inc. / PC-BSD
MFC after:	2 months
2012-07-29 11:51:48 +00:00
Edward Tomasz Napierala
aaaf515fde Fix typo in the comment. 2012-07-06 15:46:38 +00:00
Alexander Motin
107c1508fa Temporary revert r227009 to fix freeze on UP systems without PREEMPTION.
Before r215687, if some withered geom or provider could not be destroyed,
g_event thread went to sleep for 0.1s before retrying. After that change
it is just restarting immediately. r227009 made orphaned (withered) provider
to not detach immediately, but only after context switch. That made loop
inside g_event thread infinite on UP systems without PREEMPTION.

To address original problem with possible dead lock addressed by r227009
we have to fix r215687 change first, that needs some time to think and test.
2011-11-14 19:32:05 +00:00
Alexander Motin
755d1ea5b5 Make orphan() method in geom_dev asynchronous using destroy_dev_sched_cb()
instead of destroy_dev(). It moves device destruction waiting out of the
topology lock and so fixes dead lock between orphanization and closing.
Real provider and geom destruction called from swi context after device
destroyed as callback of the destroy_dev_sched_cb().
2011-11-01 23:12:22 +00:00
Justin T. Gibbs
416494d7c9 Plumb device physical path reporting from CAM devices, through GEOM and
DEVFS, and make it accessible via the diskinfo utility.

Extend GEOM's generic attribute query mechanism into generic disk consumers.
sys/geom/geom_disk.c:
sys/geom/geom_disk.h:
sys/cam/scsi/scsi_da.c:
sys/cam/ata/ata_da.c:
	- Allow disk providers to implement a new method which can override
	  the default BIO_GETATTR response, d_getattr(struct bio *).  This
	  function returns -1 if not handled, otherwise it returns 0 or an
	  errno to be passed to g_io_deliver().

sys/cam/scsi/scsi_da.c:
sys/cam/ata/ata_da.c:
	- Don't copy the serial number to dp->d_ident anymore, as the CAM XPT
	  is now responsible for returning this information via
	  d_getattr()->(a)dagetattr()->xpt_getatr().

sys/geom/geom_dev.c:
	- Implement a new ioctl, DIOCGPHYSPATH, which returns the GEOM
	  attribute "GEOM::physpath", if possible.  If the attribute request
	  returns a zero-length string, ENOENT is returned.

usr.sbin/diskinfo/diskinfo.c:
	- If the DIOCGPHYSPATH ioctl is successful, report physical path
	  data when diskinfo is executed with the '-v' option.

Submitted by:	will
Reviewed by:	gibbs
Sponsored by:	Spectra Logic Corporation

Add generic attribute change notification support to GEOM.

sys/sys/geom/geom.h:
	Add a new attrchanged method field to both g_class
	and g_geom.

sys/sys/geom/geom.h:
sys/geom/geom_event.c:
	- Provide the g_attr_changed() function that providers
	  can use to advertise attribute changes.
	- Perform delivery of attribute change notifications
	  from a thread context via the standard GEOM event
	  mechanism.

sys/geom/geom_subr.c:
	Inherit the attrchanged method from class to geom (class instance).

sys/geom/geom_disk.c:
	Provide disk_attr_changed() to provide g_attr_changed() access
	to consumers of the disk API.

sys/cam/scsi/scsi_pass.c:
sys/cam/scsi/scsi_da.c:
sys/geom/geom_dev.c:
sys/geom/geom_disk.c:
	Use attribute changed events to track updates to physical path
	information.

sys/cam/scsi/scsi_da.c:
	Add AC_ADVINFO_CHANGED to the registered asynchronous CAM
	events for this driver.  When this event occurs, and
	the updated buffer type references our physical path
	attribute, emit a GEOM attribute changed event via the
	disk_attr_changed() API.

sys/cam/scsi/scsi_pass.c:
	Add AC_ADVINFO_CHANGED to the registered asynchronous CAM
	events for this driver.  When this event occurs, update
	the physical patch devfs alias for this pass instance.

Submitted by:	gibbs
Sponsored by:	Spectra Logic Corporation
2011-06-14 17:10:32 +00:00
Alexander Motin
bd5c368604 Use make_dev_alias_p() added in r221397 to create alias dev entry.
It removes panic in case if alias name is already busy for some reason.
2011-05-03 19:12:42 +00:00
Alexander Motin
0d307e0905 - Add shim to simplify migration to the CAM-based ATA. For each new adaX
device in /dev/ create symbolic link with adY name, trying to mimic old ATA
numbering. Imitation is not complete, but should be enough in most cases to
mount file systems without touching /etc/fstab.
 - To know what behavior to mimic, restore ATA_STATIC_ID option in cases
where it was present before.
 - Add some more details to UPDATING.
2011-04-26 17:01:49 +00:00
Alexander Motin
06f4c96d39 MFgraid/head r217827:
Change BIO_GETATTR("GEOM::kerneldump") API to make set_dumper() called by
consumer (geom_dev) instead of provider (geom_disk). This allows any geom
insert it's code into the dump call chain, implementing more sophisticated
functionality then just disk partitioning.
2011-03-24 08:37:48 +00:00
Jaakko Heinonen
bc2589f5b7 Use make_dev_p(9) with the MAKEDEV_CHECKNAME flag instead of make_dev(9)
and print a diagnostic if the call fails.

This avoids a panic when a device with an invalid name is attempted to
be registered. For example the label class gets device names from
untrusted input.

Reviewed by:	freebsd-geom
2010-10-19 16:48:49 +00:00
Andriy Gapon
1bdfff2252 fix a few cases where a string is passed via format argument instead of
via %s

Most of the cases looked harmless, but this is done for the sake of
correctness.  In one case it even allowed to drop an intermediate buffer.

Found by:	clang
MFC after:	2 week
2010-06-11 19:27:21 +00:00
Alexander Motin
1c80ec0a6b Add BIO_DELETE support to ada(4):
- For SSDs use TRIM feature of DATA SET MANAGEMENT command, as defined by
ACS-2 specification working draft.
- For CompactFlash use CFA ERASE command, same as ad(4) does.

With this patch, `newfs -E /dev/ada1` was able to restore write speed of
my heavily weared OCZ Vertex SSD (firmware 1.4) up to the initial level
for the most part of it's capacity. Previous 1.3 firmware, even reportiong
TRIM capabilty bit set, was not working, reporting ABORT error for every
DSM command.

I have no idea whether it is normal, but for some reason it takes 200ms
to handle any TRIM command on this drive, that was making delete extremely
slow. But TRIM command is able to accept long list of LBAs and the length of
that list seems doesn't affect it's execution time. Implemented request
clusting algorithm allowed me to rise delete rate up to reasonable numbers,
when many parallel DELETE requests running.
2009-12-28 20:08:01 +00:00
Alexander Motin
8b30323843 Add two disk ioctls, giving user-level tools information about disk/array
stripe (optimal access block) size and offset.
2009-12-24 11:05:23 +00:00
Alexander Motin
18e42503ed Do not check proper request alignment here in geom_dev in production.
It will be checked any way later by g_io_check() in g_io_schedule_down().
It is only needed here to not trigger panic from additional check, when
INVARIANTS enabled. So cover it with #ifdef INVARIANTS. It saves two
64bit divisions per request.
2009-09-08 05:46:38 +00:00
Marcel Moolenaar
f43b57e32a Revert revisions 188839 and 188868. Use of the ioctl in geom_dev.c
is invalid because the ioctl happens without prior open. The ioctl
got introduced to provide backward compatibility for extended
partitions, but it ended up not being used because it didn't work
as expected. Since there are no consumers of the ioctl and the
implementation is broken, the best fix is to remove the code
entirely.

Spotted by:	phk
Approved by:	re (kensmith)
2009-07-08 05:56:14 +00:00
Marcel Moolenaar
59c532c500 Provide compatibility symlink for logical partitions:
1.  Extend geom_dev by having it create the symlink (i.e. call
    make_dev_alias) based on the DIOCGPROVIDERALIAS ioctl.
    In this way the functionaility is generic and thus usable
    by any geom/provider.
2.  Have g_part handle said ioctl through the devalias method,
    so that it's under control of the scheme itself. By design
    the alias will not be created for newly added partitions.
2009-02-20 04:48:40 +00:00
Ed Schouten
739b705c7e Remove unused unrhdr from GEOM character device module.
Now that make_dev() doesn't require unit numbers to be unique, there is
no need to use an unrhdr here to generate the numbers. Remove the entire
init-routine, because it is optional.
2009-01-24 18:23:19 +00:00
Ed Schouten
d3ce832719 Remove unit2minor() use from kernel code.
When I changed kern_conf.c three months ago I made device unit numbers
equal to (unneeded) device minor numbers. We used to require
bitshifting, because there were eight bits in the middle that were
reserved for a device major number. Not very long after I turned
dev2unit(), minor(), unit2minor() and minor2unit() into macro's.
The unit2minor() and minor2unit() macro's were no-ops.

We'd better not remove these four macro's from the kernel, because there
is a lot of (external) code that may still depend on them. For now it's
harmless to remove all invocations of unit2minor() and minor2unit().

Reviewed by:	kib
2008-09-26 14:19:52 +00:00
Ulf Lilleengen
f805f204b6 - Add a new ioctl for getting the provider name of a geom provider.
- Add a routine for looking up a device and checking if it is a valid geom
  provider given a partial or full path to its device node.

Reviewed by:	phk
Approved by:	pjd (mentor)
2008-09-07 13:54:57 +00:00
Ed Schouten
06d425f92e Remove the distinction between device minor and unit numbers.
Even though we got rid of device major numbers some time ago, device
drivers still need to provide unique device minor numbers to make_dev().
These numbers are only used inside the kernel. They are not related to
device major and minor numbers which are visible in devfs. These are
actually based on the inode number of the device.

It would eventually be nice to remove minor numbers entirely, but we
don't want to be too agressive here.

Because the 8-15 bits of the device number field (si_drv0) are still
reserved for the major number, there is no 1:1 mapping of the device
minor and unit numbers. Because this is now unused, remove the
restrictions on these numbers.

The MAXMAJOR definition was actually used for two purposes. It was used
to convert both the userspace and kernelspace device numbers to their
major/minor pair, which is why it is now named UMINORMASK.

minor2unit() and unit2minor() have now become useless. Both minor() and
dev2unit() now serve the same purpose. We should eventually remove some
of them, at least turning them into macro's. If devfs would become
completely minor number unaware, we could consider using si_drv0 directly,
just like si_drv1 and si_drv2.

Approved by:	philip (mentor)
2008-05-29 12:50:46 +00:00
Poul-Henning Kamp
015a11e695 Chop DIOCGDELETE from userland up in 1024 sector chunks to give geom_disk
or any other bio chopping geom a reasonable size of work.

Check for delivered signals between chunks, because the request size
and service time is unbounded.
2007-12-16 19:38:26 +00:00
Poul-Henning Kamp
eed6cda966 Don't limit BIO_DELETE requests to MAXPHYS, they perform no data
transfers, so they are not subject to the VM system limitation.
2007-12-16 18:03:31 +00:00
Pawel Jakub Dawidek
0589353ac7 Implement three new ioctls that can be used with GEOM provider:
DIOCGFLUSH - Flush write cache (sends BIO_FLUSH).

	DIOCGDELETE - Delete data (mark as unused) (sends BIO_DELETE).

	DIOCGIDENT - Get provider's uniqe and fixed identifier (asks for
		GEOM::ident attribute).

First two are self-explanatory, but the last one might not be. Here are
properties of provider's ident:

- ident value is preserved between reboots,
- provider can be detached/attached and ident is preserved,
- provider's name can change - ident can't,
- ident value should not be based on on-disk metadata; in other words
  copying whole data from one disk to another should not yield the same
  ident for the other disk,
- there could be more than one provider with the same ident, but only if
  they point at exactly the same physical storage, this is the case for
  multipathing for example,
- GEOM classes that consumes single providers and provide single providers,
  like geli, gbde, should just attach class name to the ident of the
  underlying provider,
- ident is an ASCII string (is printable),
- ident is optional and applications can't relay on its presence.

The main purpose for this is that application and remember provider's ident
and once it tries to open provider by its name again, it may compare idents
to be sure this is the right provider. If it is not (idents don't match),
then it can open provider by its ident.

OK'ed by:	phk
2007-05-05 17:02:19 +00:00
Kris Kennaway
17e910a261 make_dev(9) can be (and is) called without Giant, so there is no need to
drop the topology lock and acquire Giant around this call.

Reviewed by:	phk
2007-03-26 21:47:03 +00:00
John Baldwin
4d70511ac3 Use pause() rather than tsleep() on stack variables and function pointers. 2007-02-27 17:23:29 +00:00
John Baldwin
6e50e38fcc Use tsleep() rather than msleep() with a NULL mtx parameter. 2007-02-23 23:06:10 +00:00