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
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.
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
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
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
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
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)
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.
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
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.
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().
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
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.
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.
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
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
- 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.
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.
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)
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.
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.
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
- 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)
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)
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.
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
offset or request size which is not a multiple of the sector size, make
sure that the bio is set to indicate that no data has actually been
transferred.
The result of this is that the file offset is no longer incremented for
these requests. The fact that the file offset was incremented broke
fdisk(8)'s probing of sector size for non-512 byte sector sizes.
Reviewed by: phk, cperciva
Submitted by: mdodd
MFC after: 2 weeks
