necessary because CLOOP format lacks explicit EOF or length, so that
in the presence of padding or when the CLOOP is put onto a larger
partition upper level provider size may be larger. Bound amount
of extra data that we might touch to the max length of the compressed
block and detect zero-padding in the last cluster, which when
sector is all-zero might cause us to emit bogus I/O error after
decompression of that fails. To not make code any more complicated
that it needs to be deal with it in lazy-manner, i.e. when we
first access that specific cluster.
This change also fixes stupid mistake in the LZMA code, inherited
from geom_lzma, which does not share length of the output buffer
buffer with the decompression routine, so that in the presence
of corrupted or purposedly tailored data may easily cause heap
overflow and kernel memory corruption.
Beef up validation of the CLOOP TOC by checking that lengths of
all but the last compressed clusters match upper limit set by
the decompressor and improve some error diagnostic output while
I am here.
2.Add kern.geom.uzip.attach_to tunable to artifically limit
attaching uzip to certain devices in the dev tree only.
For example the following only makes us attaching to the
GPT labels:
kern.geom.uzip.attach_to="gpt/*"
3.Add kern.geom.uzip.noattach_to, which does opposite to the (2)
above, i.e. prevents geom_uzip from tasting / attaching to
providers matching some pattern. By default we don't attach
to our own kind, i.e. kern.geom.uzip.noattach_to="*.uzip".
It saves us quite some CPU cycles, esp on low-end embedded
systems.
Approved by: re (gjb)
Differential Revision: https://reviews.freebsd.org/D7013
The GEOM disk d_mtx is only acquired on disk creation and destruction.
It is a good candidate for replacement with a pool mutex. This eliminates
the mutex initialization and teardown and the mutex and name variables
themselves from struct disk.
sys/geom/geom_disk.h:
Take d_mtx and d_mtx_name out of struct disk.
sys/geom/geom_disk.c:
Use mtx_pool_lock() and mtx_pool_unlock() to guard the disk
initialization state instead of a dedicated mutex.
This allows removing the initialization and destruction of
d_mtx.
sys/sys/param.h:
Bump __FreeBSD_version to 1100119 for the change to struct disk.
Suggested by: jhb
Sponsored by: Spectra Logic
Approved by: re (gjb)
This will result in lock recursion and is more generally incorrect since
the completion handlers will just reinsert the BIOs into the queue we're
trying to drain.
Reviewed by: imp, ngie
Approved by: re (gjb)
MFC after: 3 weeks
Sponsored by: EMC / Isilon Storage Division
Differential Revision: https://reviews.freebsd.org/D6908
after the underlying device went away.
The problem was that callers who queue the GEOM resize provider
event didn't check to make sure that the provider had not been
withered. For the other equivalent case, g_new_provider_event(),
the code checks to see whether the provider has been withered
before queueing a g_new_provider_event() to the event thread.
In some cases, a resize provider event would come through after
the provider had been withered and all of the existing consumers
had been orphaned. When the resize event triggered a taste of
the provider, that would attach a new consumer to the now
withered provider. The wither washer (g_wither_washer() would
never be able to completely tear down the GEOM because of the
consumers that were hanging around.
The solution was to check the G_PF_WITHER provider flag before
queueing the g_resize_provider_event(), and add an assert to
g_resize_provider_event() to insure that it isn't called on a
withered provider.
sys/geom/geom_subr.c:
In g_resize_provider(), don't try to continue if the
G_PF_WITHER flag is set.
In g_resize_provider_event(), add an assert that the
G_PF_WITHER flag is not set.
In g_access(), if a provider has an error, print out the
name of the provider with the error.
Sponsored by: Spectra Logic
Approved by: re (marius)
MFC after: 3 days
device is gone.
The problem was that when disk_gone() is called, if the GEOM disk
creation process has not yet happened, the withering process
couldn't start.
We didn't record any state in the GEOM disk code, and so the d_gone()
callback to the da(4) driver never happened.
The solution is to track the state of the creation process, and
initiate the withering process from g_disk_create() if the disk is
being created.
This change does add fields to struct disk, and so I have bumped
DISK_VERSION.
geom_disk.c: Track where we are in the disk creation process,
and check to see whether our underlying disk has
gone away or not.
In disk_gone(), set a new d_goneflag variable that
g_disk_create() can check to see if it needs to
clean up the disk instance.
geom_disk.h: Add a mutex to struct disk (for internal use) disk
init level, and a gone flag.
Bump DISK_VERSION because the size of struct disk has
changed and fields have been added at the beginning.
Sponsored by: Spectra Logic
Approved by: re (marius)
otherwise the system will hang.
This is a temporarily least intrusive crutch to get certain panicing systems
dumping. The proper fix should question is g_mirror_destroy() should be called
on a panicing system at all.
Discussed with: mav
ZFS's configuration needs to be updated whenever the physical path for a
device changes, but not when a new device is introduced. This is because new
devices necessarily cause config updates, but only if they are actually
accepted into the pool.
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_geom.c
Split vdev_geom_set_physpath out of vdev_geom_attrchanged. When
setting the vdev's physical path, only request a config update if
the physical path has changed. Don't request it when opening a
device for the first time, because the config sync will happen
anyway upstack.
sys/geom/geom_dev.c
Split g_dev_set_physpath and g_dev_set_media out of
g_dev_attrchanged
Submitted by: will, asomers
MFC after: 4 weeks
Sponsored by: Spectra Logic Corp
Differential Revision: https://reviews.freebsd.org/D6428
outlived their usefulness. This allows to remove drop/pickup Giant
wrappers around GEOM calls.
Discussed with: alfred, imp, phk
Sponsored by: The FreeBSD Foundation
This change includes support for SCSI SMR drives (which conform to the
Zoned Block Commands or ZBC spec) and ATA SMR drives (which conform to
the Zoned ATA Command Set or ZAC spec) behind SAS expanders.
This includes full management support through the GEOM BIO interface, and
through a new userland utility, zonectl(8), and through camcontrol(8).
This is now ready for filesystems to use to detect and manage zoned drives.
(There is no work in progress that I know of to use this for ZFS or UFS, if
anyone is interested, let me know and I may have some suggestions.)
Also, improve ATA command passthrough and dispatch support, both via ATA
and ATA passthrough over SCSI.
Also, add support to camcontrol(8) for the ATA Extended Power Conditions
feature set. You can now manage ATA device power states, and set various
idle time thresholds for a drive to enter lower power states.
Note that this change cannot be MFCed in full, because it depends on
changes to the struct bio API that break compatilibity. In order to
avoid breaking the stable API, only changes that don't touch or depend on
the struct bio changes can be merged. For example, the camcontrol(8)
changes don't depend on the new bio API, but zonectl(8) and the probe
changes to the da(4) and ada(4) drivers do depend on it.
Also note that the SMR changes have not yet been tested with an actual
SCSI ZBC device, or a SCSI to ATA translation layer (SAT) that supports
ZBC to ZAC translation. I have not yet gotten a suitable drive or SAT
layer, so any testing help would be appreciated. These changes have been
tested with Seagate Host Aware SATA drives attached to both SAS and SATA
controllers. Also, I do not have any SATA Host Managed devices, and I
suspect that it may take additional (hopefully minor) changes to support
them.
Thanks to Seagate for supplying the test hardware and answering questions.
sbin/camcontrol/Makefile:
Add epc.c and zone.c.
sbin/camcontrol/camcontrol.8:
Document the zone and epc subcommands.
sbin/camcontrol/camcontrol.c:
Add the zone and epc subcommands.
Add auxiliary register support to build_ata_cmd(). Make sure to
set the CAM_ATAIO_NEEDRESULT, CAM_ATAIO_DMA, and CAM_ATAIO_FPDMA
flags as appropriate for ATA commands.
Add a new get_ata_status() function to parse ATA result from SCSI
sense descriptors (for ATA passthrough over SCSI) and ATA I/O
requests.
sbin/camcontrol/camcontrol.h:
Update the build_ata_cmd() prototype
Add get_ata_status(), zone(), and epc().
sbin/camcontrol/epc.c:
Support for ATA Extended Power Conditions features. This includes
support for all features documented in the ACS-4 Revision 12
specification from t13.org (dated February 18, 2016).
The EPC feature set allows putting a drive into a power power mode
immediately, or setting timeouts so that the drive will
automatically enter progressively lower power states after various
idle times.
sbin/camcontrol/fwdownload.c:
Update the firmware download code for the new build_ata_cmd()
arguments.
sbin/camcontrol/zone.c:
Implement support for Shingled Magnetic Recording (SMR) drives
via SCSI Zoned Block Commands (ZBC) and ATA Zoned Device ATA
Command Set (ZAC).
These specs were developed in concert, and are functionally
identical. The primary differences are due to SCSI and ATA
differences. (SCSI is big endian, ATA is little endian, for
example.)
This includes support for all commands defined in the ZBC and
ZAC specs.
sys/cam/ata/ata_all.c:
Decode a number of additional ATA command names in ata_op_string().
Add a new CCB building function, ata_read_log().
Add ata_zac_mgmt_in() and ata_zac_mgmt_out() CCB building
functions. These support both DMA and NCQ encapsulation.
sys/cam/ata/ata_all.h:
Add prototypes for ata_read_log(), ata_zac_mgmt_out(), and
ata_zac_mgmt_in().
sys/cam/ata/ata_da.c:
Revamp the ada(4) driver to support zoned devices.
Add four new probe states to gather information needed for zone
support.
Add a new adasetflags() function to avoid duplication of large
blocks of flag setting between the async handler and register
functions.
Add new sysctl variables that describe zone support and paramters.
Add support for the new BIO_ZONE bio, and all of its subcommands:
DISK_ZONE_OPEN, DISK_ZONE_CLOSE, DISK_ZONE_FINISH, DISK_ZONE_RWP,
DISK_ZONE_REPORT_ZONES, and DISK_ZONE_GET_PARAMS.
sys/cam/scsi/scsi_all.c:
Add command descriptions for the ZBC IN/OUT commands.
Add descriptions for ZBC Host Managed devices.
Add a new function, scsi_ata_pass() to do ATA passthrough over
SCSI. This will eventually replace scsi_ata_pass_16() -- it
can create the 12, 16, and 32-byte variants of the ATA
PASS-THROUGH command, and supports setting all of the
registers defined as of SAT-4, Revision 5 (March 11, 2016).
Change scsi_ata_identify() to use scsi_ata_pass() instead of
scsi_ata_pass_16().
Add a new scsi_ata_read_log() function to facilitate reading
ATA logs via SCSI.
sys/cam/scsi/scsi_all.h:
Add the new ATA PASS-THROUGH(32) command CDB. Add extended and
variable CDB opcodes.
Add Zoned Block Device Characteristics VPD page.
Add ATA Return SCSI sense descriptor.
Add prototypes for scsi_ata_read_log() and scsi_ata_pass().
sys/cam/scsi/scsi_da.c:
Revamp the da(4) driver to support zoned devices.
Add five new probe states, four of which are needed for ATA
devices.
Add five new sysctl variables that describe zone support and
parameters.
The da(4) driver supports SCSI ZBC devices, as well as ATA ZAC
devices when they are attached via a SCSI to ATA Translation (SAT)
layer. Since ZBC -> ZAC translation is a new feature in the T10
SAT-4 spec, most SATA drives will be supported via ATA commands
sent via the SCSI ATA PASS-THROUGH command. The da(4) driver will
prefer the ZBC interface, if it is available, for performance
reasons, but will use the ATA PASS-THROUGH interface to the ZAC
command set if the SAT layer doesn't support translation yet.
As I mentioned above, ZBC command support is untested.
Add support for the new BIO_ZONE bio, and all of its subcommands:
DISK_ZONE_OPEN, DISK_ZONE_CLOSE, DISK_ZONE_FINISH, DISK_ZONE_RWP,
DISK_ZONE_REPORT_ZONES, and DISK_ZONE_GET_PARAMS.
Add scsi_zbc_in() and scsi_zbc_out() CCB building functions.
Add scsi_ata_zac_mgmt_out() and scsi_ata_zac_mgmt_in() CCB/CDB
building functions. Note that these have return values, unlike
almost all other CCB building functions in CAM. The reason is
that they can fail, depending upon the particular combination
of input parameters. The primary failure case is if the user
wants NCQ, but fails to specify additional CDB storage. NCQ
requires using the 32-byte version of the SCSI ATA PASS-THROUGH
command, and the current CAM CDB size is 16 bytes.
sys/cam/scsi/scsi_da.h:
Add ZBC IN and ZBC OUT CDBs and opcodes.
Add SCSI Report Zones data structures.
Add scsi_zbc_in(), scsi_zbc_out(), scsi_ata_zac_mgmt_out(), and
scsi_ata_zac_mgmt_in() prototypes.
sys/dev/ahci/ahci.c:
Fix SEND / RECEIVE FPDMA QUEUED in the ahci(4) driver.
ahci_setup_fis() previously set the top bits of the sector count
register in the FIS to 0 for FPDMA commands. This is okay for
read and write, because the PRIO field is in the only thing in
those bits, and we don't implement that further up the stack.
But, for SEND and RECEIVE FPDMA QUEUED, the subcommand is in that
byte, so it needs to be transmitted to the drive.
In ahci_setup_fis(), always set the the top 8 bits of the
sector count register. We need it in both the standard
and NCQ / FPDMA cases.
sys/geom/eli/g_eli.c:
Pass BIO_ZONE commands through the GELI class.
sys/geom/geom.h:
Add g_io_zonecmd() prototype.
sys/geom/geom_dev.c:
Add new DIOCZONECMD ioctl, which allows sending zone commands to
disks.
sys/geom/geom_disk.c:
Add support for BIO_ZONE commands.
sys/geom/geom_disk.h:
Add a new flag, DISKFLAG_CANZONE, that indicates that a given
GEOM disk client can handle BIO_ZONE commands.
sys/geom/geom_io.c:
Add a new function, g_io_zonecmd(), that handles execution of
BIO_ZONE commands.
Add permissions check for BIO_ZONE commands.
Add command decoding for BIO_ZONE commands.
sys/geom/geom_subr.c:
Add DDB command decoding for BIO_ZONE commands.
sys/kern/subr_devstat.c:
Record statistics for REPORT ZONES commands. Note that the
number of bytes transferred for REPORT ZONES won't quite match
what is received from the harware. This is because we're
necessarily counting bytes coming from the da(4) / ada(4) drivers,
which are using the disk_zone.h interface to communicate up
the stack. The structure sizes it uses are slightly different
than the SCSI and ATA structure sizes.
sys/sys/ata.h:
Add many bit and structure definitions for ZAC, NCQ, and EPC
command support.
sys/sys/bio.h:
Convert the bio_cmd field to a straight enumeration. This will
yield more space for additional commands in the future. After
change r297955 and other related changes, this is now possible.
Converting to an enumeration will also prevent use as a bitmask
in the future.
sys/sys/disk.h:
Define the DIOCZONECMD ioctl.
sys/sys/disk_zone.h:
Add a new API for managing zoned disks. This is very close to
the SCSI ZBC and ATA ZAC standards, but uses integers in native
byte order instead of big endian (SCSI) or little endian (ATA)
byte arrays.
This is intended to offer to the complete feature set of the ZBC
and ZAC disk management without requiring the application developer
to include SCSI or ATA headers. We also use one set of headers
for ioctl consumers and kernel bio-level consumers.
sys/sys/param.h:
Bump __FreeBSD_version for sys/bio.h command changes, and inclusion
of SMR support.
usr.sbin/Makefile:
Add the zonectl utility.
usr.sbin/diskinfo/diskinfo.c
Add disk zoning capability to the 'diskinfo -v' output.
usr.sbin/zonectl/Makefile:
Add zonectl makefile.
usr.sbin/zonectl/zonectl.8
zonectl(8) man page.
usr.sbin/zonectl/zonectl.c
The zonectl(8) utility. This allows managing SCSI or ATA zoned
disks via the disk_zone.h API. You can report zones, reset write
pointers, get parameters, etc.
Sponsored by: Spectra Logic
Differential Revision: https://reviews.freebsd.org/D6147
Reviewed by: wblock (documentation)
Currently, Application Processors (non-boot CPUs) are started by
MD code at SI_SUB_CPU, but they are kept waiting in a "pen" until
SI_SUB_SMP at which point they are released to run kernel threads.
SI_SUB_SMP is one of the last SYSINIT levels, so APs don't enter
the scheduler and start running threads until fairly late in the
boot.
This change moves SI_SUB_SMP up to just before software interrupt
threads are created allowing the APs to start executing kernel
threads much sooner (before any devices are probed). This allows
several initialization routines that need to perform initialization
on all CPUs to now perform that initialization in one step rather
than having to defer the AP initialization to a second SYSINIT run
at SI_SUB_SMP. It also permits all CPUs to be available for
handling interrupts before any devices are probed.
This last feature fixes a problem on with interrupt vector exhaustion.
Specifically, in the old model all device interrupts were routed
onto the boot CPU during boot. Later after the APs were released at
SI_SUB_SMP, interrupts were redistributed across all CPUs.
However, several drivers for multiqueue hardware allocate N interrupts
per CPU in the system. In a system with many CPUs, just a few drivers
doing this could exhaust the available pool of interrupt vectors on
the boot CPU as each driver was allocating N * mp_ncpu vectors on the
boot CPU. Now, drivers will allocate interrupts on their desired CPUs
during boot meaning that only N interrupts are allocated from the boot
CPU instead of N * mp_ncpu.
Some other bits of code can also be simplified as smp_started is
now true much earlier and will now always be true for these bits of
code. This removes the need to treat the single-CPU boot environment
as a special case.
As a transition aid, the new behavior is available under a new kernel
option (EARLY_AP_STARTUP). This will allow the option to be turned off
if need be during initial testing. I plan to enable this on x86 by
default in a followup commit in the next few days and to have all
platforms moved over before 11.0. Once the transition is complete,
the option will be removed along with the !EARLY_AP_STARTUP code.
These changes have only been tested on x86. Other platform maintainers
are encouraged to port their architectures over as well. The main
things to check for are any uses of smp_started in MD code that can be
simplified and SI_SUB_SMP SYSINITs in MD code that can be removed in
the EARLY_AP_STARTUP case (e.g. the interrupt shuffling).
PR: kern/199321
Reviewed by: markj, gnn, kib
Sponsored by: Netflix
In struct:gctl_req, nargs is unsigned.
In mirror:
g_mirror_syncreqs is unsigned.
In raid:
in struct:g_raid_volume, v_disks_count is unsigned.
In virstor:
in struct:g_virstor_softc, n_components is unsigned.
MFC after: 2 weeks
This value is u32 on disk, but assigned to an int in memory. After we do the
implicit conversion via assignment, check that the result is at least one[1]
(non-negative[2]).
1. The subsequent for-loop iterates from gpt_entries minus one, down, until
reaching zero. A negative or zero initial index results in undefined signed
integer overflow.
2. It is also used to index into arrays later.
In practice, we expected non-malicious disks to contain small positive values.
Reported by: Coverity
CID: 1223202
Sponsored by: EMC / Isilon Storage Division
rounddown2 tends to produce longer lines than the original code
and when the code has a high indentation level it was not really
advantageous to do the replacement.
This tries to strike a balance between readability using the macros
and flexibility of having the expressions, so not everything is
converted.
sys/geom/geom_disk.c:
disk_attr_changed(): Generate a devctl event of type GEOM:<attr> for
every call.
MFC after: 4 weeks
Sponsored by: Spectra Logic Corp
Differential Revision: https://reviews.freebsd.org/D5952
This flag indicates that the user wishes to use the GELIBOOT feature to boot from a fully encrypted root file system.
Currently, GELIBOOT does not support key files, and in the future when it does, they will be loaded differently.
Due to the design of GELI, and the desire for secrecy, the GELI metadata does not know if key files are used or not, it just adds the key material (if any) to the HMAC before the optional passphrase, so there is no way to tell if a GELI partition requires key files or not.
Since the GELIBOOT code in boot2 and the loader does not support keys, they will now only attempt to attach if this flag is set. This will stop GELIBOOT from prompting for passwords to GELIs that it cannot decrypt, disrupting the boot process
PR: 208251
Reviewed by: ed, oshogbo, wblock
Sponsored by: ScaleEngine Inc.
Differential Revision: https://reviews.freebsd.org/D5867
For the !gsp case there some chance of returning an uninitialized
return value. Prevent that from happening by initializing the
error value.
CID: 1006421
and geom_uncompress(4):
1. mkuzip(8):
- Proper support for eliminating all-zero blocks when compressing an
image. This feature is already supported by the geom_uzip(4) module
and CLOOP format in general, so it's just a matter of making mkuzip(8)
match. It should be noted, however that this feature while it sounds
great, results in very slight improvement in the overall compression
ratio, since compressing default 16k all-zero block produces only 39
bytes compressed output block, which is 99.8% compression ratio. With
typical average compression ratio of amd64 binaries and data being
around 60-70% the difference between 99.8% and 100.0% is not that
great further diluted by the ratio of number of zero blocks in the
uncompressed image to the overall number of blocks being less than
0.5 (typically). However, this may be important from performance
standpoint, so that kernel are not spinning its wheels decompressing
those empty blocks every time this zero region is read. It could also
be important when you create huge image mostly filled with zero
blocks for testing purposes.
- New feature allowing to de-duplicate output image. It turns out that
if you twist CLOOP format a bit you can do that as well. And unlike
zero-blocks elimination, this gives a noticeable improvement in the
overall compression ratio, reducing output image by something like
3-4% on my test UFS2 3GB image consisting of full FreeBSD base system
plus some of the packages (openjdk, apache etc), about 2.3GB worth of
file data (800+MB compressed). The only caveat is that images created
with this feature "on" would not work on older versions of FeeBSDxi
kernel, hence it's turned off by default.
- provide options to control both features and document them in manual
page.
- merge in all relevant LZMA compression support from the mkulzma(8),
add new option to select between both.
- switch license from ad-hoc beerware into standard 2-clause BSD.
2. geom_uzip(4):
- implement support for de-duplicated images;
- optimize some code paths to handle "all-zero" blocks without reading
any compressed data;
- beef up manual page to explain that geom_uzip(4) is not limited only
to md(4) images. The compressed data can be written to the block
device and accessed directly via magic of GEOM(4) and devfs(4),
including to mount root fs from a compressed drive.
- convert debug log code from being compiled in conditionally into
being present all the time and provide two sysctls to turn it on or
off. Due to intended use of the module, it can be used in
environments where there may not be a luxury to put new kernel with
debug code enabled. Having those options handy allows debug issues
without as much problem by just having access to serial console or
network shell access to a box/appliance. The resulting additional
CPU cycles are just few int comparisons and branches, and those are
minuscule when compared to data decompression which is the main
feature of the module.
- hopefully improve robustness and resiliency of the geom_uzip(4) by
performing some of the data validation / range checking on the TOC
entries and rejecting to attach to an image if those checks fail.
- merge in all relevant LZMA decompression support from the
geom_uncompress(4), enable automatically when appropriate format is
indicated in the header.
- move compilation work into its own worker thread so that it does not
clog g_up. This allows multiple instances work in parallel utilizing
smp cores.
- document new knobs in the manual page.
Reviewed by: adrian
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D5333
for all struct bio you get back from g_{new,alloc}_bio. Temporary
bios that you create on the stack or elsewhere should use this before
first use of the bio, and between uses of the bio. At the moment, it
is nothing more than a wrapper around bzero, but that may change in
the future. The wrapper also removes one place where we encode the
size of struct bio in the KBI.
The upcoming GELI support in the loader reuses parts of this code
Some ifdefs are added, and some code is moved outside of existing ifdefs
The HMAC parts of GELI are broken out into their own file, to separate
them from the kernel crypto/openssl dependant parts that are replaced
in the boot code.
Passed the GELI regression suite (tools/regression/geom/eli)
Files=20 Tests=14996
Result: PASS
Reviewed by: pjd, delphij
MFC after: 1 week
Sponsored by: ScaleEngine Inc.
Differential Revision: https://reviews.freebsd.org/D4699
cperciva's libmd implementation is 5-30% faster
The same was done for SHA256 previously in r263218
cperciva's implementation was lacking SHA-384 which I implemented, validated against OpenSSL and the NIST documentation
Extend sbin/md5 to create sha384(1)
Chase dependancies on sys/crypto/sha2/sha2.{c,h} and replace them with sha512{c.c,.h}
Reviewed by: cperciva, des, delphij
Approved by: secteam, bapt (mentor)
MFC after: 2 weeks
Sponsored by: ScaleEngine Inc.
Differential Revision: https://reviews.freebsd.org/D3929
If geom_map fails to find the end of a mapped partition based on a search, it would return the incorrect error message, stating it could not parse the START value
Reviewed by: adrian
Approved by: bapt (mentor)
Sponsored by: ScaleEngine Inc.
Differential Revision: https://reviews.freebsd.org/D4187
When a multipath member is orphaned its access members are zeroed before its
removed if marked for wither, so prevent any future calls to g_access on
such members.
This prevents a panic on debug kernels which validates the resultant values
aren't negative.
Reviewed by: mav
MFC after: 2 weeks
Sponsored by: Multiplay
Differential Revision: https://reviews.freebsd.org/D4416
When we are detecting a partition table and didn't find PMBR, try to
read backup GPT header from the last sector and if it is correct,
assume that we have GPT.
Reviewed by: rpokala
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D4282
