This reverts commit dc855f8bdf.
Support existing users of ext4 who upgrade kernel version
Test: runs
Bug: 210958368
Change-Id: I06ad3c7870b67080dfd6d72917751b20193a4fd6
Signed-off-by: Paul Lawrence <paullawrence@google.com>
Signed-off-by: Sivasri Kumar, Vanka <quic_svanka@quicinc.com>
(cherry picked from commit 63a1e5f1d0)
dm-bow provides checkpoint functionality for filesystems that do not
have built in checkpointings (like ext4). As of Android 13, using f2fs
is mandatory for userdata, so we no longer need dm-bow.
Bug: 129280212
Test: Builds
Signed-off-by: Paul Lawrence <paullawrence@google.com>
Change-Id: I5f1c50dc89925debcfb1b32ec43fed981ce016a3
Move the block holder code into a separate file as it is not in any way
related to the other block_dev.c code, and add a new selectable config
option for it so that we don't have to build it without any remapped
drivers selected.
The Kconfig symbol contains a _DEPRECATED suffix to match the comments
added in commit 49731baa41
("block: restore multiple bd_link_disk_holder() support").
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Link: https://lore.kernel.org/r/20210804094147.459763-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Mark the three personalities (linear, fault and multipath) as deprecated
because:
1. people can use dm multipath or nvme multipath.
2. linear is already deprecated in MODULE_ALIAS.
3. no one actively using fault.
Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <song@kernel.org>
This driver is not used and can cause problems if used on modern
devices. Remove it.
This reverts commit 6115619831.
Bug: 185178770
Signed-off-by: Alistair Delva <adelva@google.com>
Change-Id: I1d5acb96dda765a1e3ea0cf62a3bf4b2a78892ea
Steps on the way to 5.12-rc1
Resolves merge conflicts in:
block/keyslot-manager.c
drivers/md/dm-flakey.c
drivers/md/dm-linear.c
drivers/md/dm-table.c
include/linux/keyslot-manager.h
Cc: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I0299acc540b73422c3a5d98dc32d4053063f8da1
Commit 27f5411a71 ("dm crypt: support using encrypted keys") extended
dm-crypt to allow use of "encrypted" keys along with "user" and "logon".
Along the same lines, teach dm-crypt to support "trusted" keys as well.
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Without crc32 support, this driver fails to link:
arm-linux-gnueabi-ld: drivers/md/dm-zoned-metadata.o: in function `dmz_write_sb':
dm-zoned-metadata.c:(.text+0xe98): undefined reference to `crc32_le'
arm-linux-gnueabi-ld: drivers/md/dm-zoned-metadata.o: in function `dmz_check_sb':
dm-zoned-metadata.c:(.text+0x7978): undefined reference to `crc32_le'
Fixes: 3b1a94c88b ("dm zoned: drive-managed zoned block device target")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The integrity target relies on skcipher for encryption/decryption, but
certain kernel configurations may not enable CRYPTO_SKCIPHER, leading to
compilation errors due to unresolved symbols. Explicitly select
CRYPTO_SKCIPHER for DM_INTEGRITY, since it is unconditionally dependent
on it.
Signed-off-by: Anthony Iliopoulos <ailiop@suse.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
dm-user is essentially FUSE for block devices: as BIOs come in through
device mapper they are proxied to a userspace daemon via a control misc
device.
This is very much a work in progress. There's a handful of FIXMEs
spread throughout the code with more details. As far as I know there is
nothing broken with the current code, there's just more work to do.
Test: Ran the selftests on the version of this I'm developing for Linus'
tree, on both 4.19 and 5.8.
Bug: 161496058
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Change-Id: If5bcd8a43c3db5b556563ba303f474dd0d2902e8
This patch adds a path selector that selects paths based on a CPU to
path mapping the user passes in and what CPU we are executing on. The
primary user for this PS is where the app is optimized to use specific
CPUs so other PSs undo the apps handy work, and the storage and it's
transport are not a bottlneck.
For these io-affinity PS setups a path's transport/interconnect
perf is not going to flucuate a lot and there is no major differences
between paths, so QL/HST smarts do not help and RR always messes up
what the app is trying to do.
On a system with 16 cores, where you have a job per CPU:
fio --filename=/dev/dm-0 --direct=1 --rw=randrw --bs=4k \
--ioengine=libaio --iodepth=128 --numjobs=16
and a dm-multipath device setup where each CPU is mapped to one path:
// When in mq mode I had to set dm_mq_nr_hw_queues=$NUM_PATHS.
// Bio mode also showed similar results.
0 16777216 multipath 0 0 1 1 io-affinity 0 16 1 8:16 1 8:32 2 8:64 4
8:48 8 8:80 10 8:96 20 8:112 40 8:128 80 8:144 100 8:160 200 8:176
400 8:192 800 8:208 1000 8:224 2000 8:240 4000 65:0 8000
we can see a IOPs increase of 25%.
The percent increase depends on the device and interconnect. For a
slower/medium speed path/device that can do around 180K IOPs a path
if you ran that fio command to it directly we saw a 25% increase like
above. Slower path'd devices that could do around 90K per path showed
maybe around a 2 - 5% increase. If you use something like null_blk or
scsi_debug which can multi-million IOPs and hack it up so each device
they export shows up as a path then you see 50%+ increases.
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Add a new configuration DM_VERITY_VERIFY_ROOTHASH_SIG_SECONDARY_KEYRING
to enable dm-verity signatures to be verified against the secondary
trusted keyring. Instead of relying on the builtin trusted keyring
(with hard-coded certificates), the second trusted keyring can include
certificate authorities from the builtin trusted keyring and child
certificates loaded at run time. Using the secondary trusted keyring
enables to use dm-verity disks (e.g. loop devices) signed by keys which
did not exist at kernel build time, leveraging the certificate chain of
trust model. In practice, this makes it possible to update certificates
without kernel update and reboot, aligning with module and kernel
(kexec) signature verification which already use the secondary trusted
keyring.
Signed-off-by: Mickaël Salaün <mic@linux.microsoft.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
With commit f70f74d15c ("kconfig: remove '---help---' support") the
"---help---" marking is no longer allowed in Kconfig files.
Unfortunately some old ANDROID patches used this deprecated markings,
which breaks the build.
Fix this up by converting them to the correct style "help"
Bug: 156285741
Bug: 146517987
Bug: 31622239
Bug: 120445368
Bug: 119769411
Bug: 129280212
Fixes: 7f62740112 ("ANDROID: add support for vendor hooks")
Fixes: 2dec8234fe ("ANDROID: gnss: Add command line test driver")
Fixes: 6115619831 ("ANDROID: AVB error handler to invalidate vbmeta partition.")
Fixes: 0ce3eb37e9 ("ANDROID: dm-bow: Add dm-bow feature")
Cc: Todd Kjos <tkjos@google.com>
Cc: Alistair Delva <adelva@google.com>
Cc: David Zeuthen <zeuthen@google.com>
Cc: Paul Lawrence <paullawrence@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I8a503c34b5b4dac6dc3e24afbefa10223a6fd946
Steps on the way to 5.9-rc1
Resolves conflicts in:
drivers/irqchip/qcom-pdc.c
include/linux/device.h
net/xfrm/xfrm_state.c
security/lsm_audit.c
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I4aeb3d04f4717714a421721eb3ce690c099bb30a
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.
Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.
Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Link: https://lore.kernel.org/r/20200627103138.71885-1-grandmaster@al2klimov.de
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Since commit 84af7a6194 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.
This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.
There are a variety of indentation styles found.
a) 4 spaces + '---help---'
b) 7 spaces + '---help---'
c) 8 spaces + '---help---'
d) 1 space + 1 tab + '---help---'
e) 1 tab + '---help---' (correct indentation)
f) 1 tab + 1 space + '---help---'
g) 1 tab + 2 spaces + '---help---'
In order to convert all of them to 1 tab + 'help', I ran the
following commend:
$ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
This new selector keeps an exponential moving average of the service
time for each path (losely defined as delta between start_io and
end_io), and uses this along with the number of inflight requests to
estimate future service time for a path. Since we don't have a prober
to account for temporally slow paths, re-try "slow" paths every once in
a while (num_paths * historical_service_time). To account for fast paths
transitioning to slow, if a path has not completed any request within
(num_paths * historical_service_time), limit the number of outstanding
requests. To account for low volume situations where number of
inflight IOs would be zero, the last finish time of each path is
factored in.
Signed-off-by: Khazhismel Kumykov <khazhy@google.com>
Co-developed-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
This new target is similar to the linear target except that it emulates
a smaller logical block size on a device with a larger logical block
size. Its main purpose is to emulate 512 byte sectors on 4K native
disks (i.e. 512e).
See Documentation/admin-guide/device-mapper/dm-ebs.rst for details.
Reviewed-by: Damien Le Moal <DamienLeMoal@wdc.com>
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org> [Kconfig fixes]
Signed-off-by: Zheng Bin <zhengbin13@huawei.com> [static fixes]
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Allow one to use "encrypted" in addition to "user" and "logon" key
types for device encryption.
Signed-off-by: Dmitry Baryshkov <dmitry_baryshkov@mentor.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
While dm-default-key no longer requires that the filesystem is also
using inline encryption (i.e. mounted with '-o inlinecrypt'), it does
still rely on the inline crypto hooks like fscrypt_set_bio_crypt_ctx()
being built into the kernel rather than stubbed out, as these are used
to set the bi_skip_dm_default_key flag on bios for encrypted files.
I.e., CONFIG_FS_ENCRYPTION_INLINE_CRYPT=y is still needed.
The proper solution is to fix these hooks to handle DM_DEFAULT_KEY &&
!FS_ENCRYPTION_INLINE_CRYPT, but that would introduce a case that
wouldn't get tested. So for now, to avoid problems just make
dm-default-key depend on FS_ENCRYPTION_INLINE_CRYPT.
Test: make gki_defconfig
echo CONFIG_FS_ENCRYPTION_INLINE_CRYPT=n >> .config
make olddefconfig
grep CONFIG_DM_DEFAULT_KEY .config # was disabled
Bug: 147814592
Change-Id: Ie52686a72d5d14457d87dcf81677e33e291680bb
Signed-off-by: Eric Biggers <ebiggers@google.com>
Add a device-mapper target "dm-default-key" which assigns an encryption
key to bios that aren't for the contents of an encrypted file.
This ensures that all blocks on-disk will be encrypted with some key,
without the performance hit of file contents being encrypted twice when
fscrypt (File-Based Encryption) is used.
It is only appropriate to use dm-default-key when key configuration is
tightly controlled, like it is in Android, such that all fscrypt keys
are at least as hard to compromise as the default key.
Compared to the original version of dm-default-key, this has been
modified to use the new vendor-independent inline encryption framework
(which works even when no inline encryption hardware is present), the
table syntax has been changed to match dm-crypt, and support for
specifying Adiantum encryption has been added. These changes also mean
that dm-default-key now always explicitly specifies the DUN (the IV).
Also, to handle f2fs moving blocks of encrypted files around without the
key, and to handle ext4 and f2fs filesystems mounted without
'-o inlinecrypt', the mapping logic is no longer "set a key on the bio
if it doesn't have one already", but rather "set a key on the bio unless
the bio has the bi_skip_dm_default_key flag set". Filesystems set this
flag on *all* bios for encrypted file contents, regardless of whether
they are encrypting/decrypting the file using inline encryption or the
traditional filesystem-layer encryption, or moving the raw data.
For the bi_skip_dm_default_key flag, a new field in struct bio is used
rather than a bit in bi_opf so that fscrypt_set_bio_crypt_ctx() can set
the flag, minimizing the changes needed to filesystems. (bi_opf is
usually overwritten after fscrypt_set_bio_crypt_ctx() is called.)
Bug: 137270441
Bug: 147814592
Change-Id: I69c9cd1e968ccf990e4ad96e5115b662237f5095
Signed-off-by: Eric Biggers <ebiggers@google.com>
Adjust indentation from spaces to tab (+optional two spaces) as in
coding style with command like:
$ sed -e 's/^ /\t/' -i */Kconfig
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
To make the 5.4-rc1 merge easier, merge at a prerelease point in time
before the final release happens.
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I29b683c837ed1a3324644dbf9bf863f30740cd0b
Add the dm-clone target, which allows cloning of arbitrary block
devices.
dm-clone produces a one-to-one copy of an existing, read-only source
device into a writable destination device: It presents a virtual block
device which makes all data appear immediately, and redirects reads and
writes accordingly.
The main use case of dm-clone is to clone a potentially remote,
high-latency, read-only, archival-type block device into a writable,
fast, primary-type device for fast, low-latency I/O. The cloned device
is visible/mountable immediately and the copy of the source device to
the destination device happens in the background, in parallel with user
I/O.
When the cloning completes, the dm-clone table can be removed altogether
and be replaced, e.g., by a linear table, mapping directly to the
destination device.
For further information and examples of how to use dm-clone, please read
Documentation/admin-guide/device-mapper/dm-clone.rst
Suggested-by: Vangelis Koukis <vkoukis@arrikto.com>
Co-developed-by: Ilias Tsitsimpis <iliastsi@arrikto.com>
Signed-off-by: Ilias Tsitsimpis <iliastsi@arrikto.com>
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Replace the explicit ESSIV handling in the dm-crypt driver with calls
into the crypto API, which now possesses the capability to perform
this processing within the crypto subsystem.
Note that we reorder the AEAD cipher_api string parsing with the TFM
instantiation: this is needed because cipher_api is mangled by the
ESSIV handling, and throws off the parsing of "authenc(" otherwise.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The verification is to support cases where the root hash is not secured
by Trusted Boot, UEFI Secureboot or similar technologies.
One of the use cases for this is for dm-verity volumes mounted after
boot, the root hash provided during the creation of the dm-verity volume
has to be secure and thus in-kernel validation implemented here will be
used before we trust the root hash and allow the block device to be
created.
The signature being provided for verification must verify the root hash
and must be trusted by the builtin keyring for verification to succeed.
The hash is added as a key of type "user" and the description is passed
to the kernel so it can look it up and use it for verification.
Adds CONFIG_DM_VERITY_VERIFY_ROOTHASH_SIG which can be turned on if root
hash verification is needed.
Kernel commandline dm_verity module parameter 'require_signatures' will
indicate whether to force root hash signature verification (for all dm
verity volumes).
Signed-off-by: Jaskaran Khurana <jaskarankhurana@linux.microsoft.com>
Tested-and-Reviewed-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The DM support describes lots of aspects related to mapped
disk partitions from the userspace PoV.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The conversion is actually:
- add blank lines and indentation in order to identify paragraphs;
- fix tables markups;
- add some lists markups;
- mark literal blocks;
- adjust title markups.
At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Add SPDX license identifiers to all Make/Kconfig files which:
- Have no license information of any form
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Based on https://www.redhat.com/archives/dm-devel/2019-March/msg00025.html
Third version of dm-bow. Key changes:
Free list added
Support for block sizes other than 4k
Handles writes during trim phase, and overlapping trims
Integer overflow error
Support trims even if underlying device doesn't
Numerous small bug fixes
bow == backup on write
USE CASE:
dm-bow takes a snapshot of an existing file system before mounting.
The user may, before removing the device, commit the snapshot.
Alternatively the user may remove the device and then run a command
line utility to restore the device to its original state.
dm-bow does not require an external device
dm-bow efficiently uses all the available free space on the file system.
IMPLEMENTATION:
dm-bow can be in one of three states.
In state one, the free blocks on the device are identified by issuing
an FSTRIM to the filesystem.
In state two, any writes cause the overwritten data to be backup up
to the available free space. While in this state, the device can be
restored by unmounting the filesystem, removing the dm-bow device
and running a usermode tool over the underlying device.
In state three, the changes are committed, dm-bow is in pass-through
mode and the drive can no longer be restored.
It is planned to use this driver to enable restoration of a failed
update attempt on Android devices using ext4.
Test: Can boot Android with userdata mounted on this device. Can commit
userdata after SUW has run. Can then reboot, make changes and roll back.
Known issues:
Mutex is held around entire flush operation, including lengthy I/O. Plan
is to convert to state machine with pending queues.
Interaction with block encryption is unknown, especially with respect
to sector 0.
Bug: 119769411
Bug: 129280212
Test: Dogfooded on Wahoo.
Ran under Cuttlefish, running VtsKernelBowTest &
VtsKernelCheckpointTest tests against 4.19, 4.14 & 4.9 kernels
Change-Id: Id70988bbd797ebe3e76fc175094388b423c8da8c
Signed-off-by: Paul Lawrence <paullawrence@google.com>
If androidboot.vbmeta.invalidate_on_error is 'yes' and
androidboot.vbmeta.device is set and points to a device with vbmeta
magic, this header will be overwritten upon an irrecoverable dm-verity
error. The side-effect of this is that the slot will fail to verify on
next reboot, effectively triggering the boot loader to fallback to
another slot. This work both if the vbmeta struct is at the start of a
partition or if there's an AVB footer at the end.
This code is based on drivers/md/dm-verity-chromeos.c from ChromiumOS.
Bug: 31622239
Bug: 120445368
Test: Manually tested (other arch).
Signed-off-by: David Zeuthen <zeuthen@google.com>
[astrachan: re-diffed against a kernel without dm-android-verity]
Change-Id: I571b5a75461da38ad832a9bea33c298bef859e26
Signed-off-by: Alistair Strachan <astrachan@google.com>
Add the dm-dust target, which simulates the behavior of bad sectors
at arbitrary locations, and the ability to enable the emulation of
the read failures at an arbitrary time.
This target behaves similarly to a linear target. At a given time,
the user can send a message to the target to start failing read
requests on specific blocks. When the failure behavior is enabled,
reads of blocks configured "bad" will fail with EIO.
Writes of blocks configured "bad" will result in the following:
1. Remove the block from the "bad block list".
2. Successfully complete the write.
After this point, the block will successfully contain the written
data, and will service reads and writes normally. This emulates the
behavior of a "remapped sector" on a hard disk drive.
dm-dust provides logging of which blocks have been added or removed
to the "bad block list", as well as logging when a block has been
removed from the bad block list. These messages can be used
alongside the messages from the driver using a dm-dust device to
analyze the driver's behavior when a read fails at a given time.
(This logging can be reduced via a "quiet" mode, if desired.)
NOTE: If the block size is larger than 512 bytes, only the first sector
of each "dust block" is detected. Placing a limiting layer above a dust
target, to limit the minimum I/O size to the dust block size, will
ensure proper emulation of the given large block size.
Signed-off-by: Bryan Gurney <bgurney@redhat.com>
Co-developed-by: Joe Shimkus <jshimkus@redhat.com>
Co-developed-by: John Dorminy <jdorminy@redhat.com>
Co-developed-by: John Pittman <jpittman@redhat.com>
Co-developed-by: Thomas Jaskiewicz <tjaskiew@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Add a "create" module parameter, which allows device-mapper targets to
be configured at boot time. This enables early use of DM targets in the
boot process (as the root device or otherwise) without the need of an
initramfs.
The syntax used in the boot param is based on the concise format from
the dmsetup tool to follow the rule of least surprise:
dmsetup table --concise /dev/mapper/lroot
Which is:
dm-mod.create=<name>,<uuid>,<minor>,<flags>,<table>[,<table>+][;<name>,<uuid>,<minor>,<flags>,<table>[,<table>+]+]
Where,
<name> ::= The device name.
<uuid> ::= xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx | ""
<minor> ::= The device minor number | ""
<flags> ::= "ro" | "rw"
<table> ::= <start_sector> <num_sectors> <target_type> <target_args>
<target_type> ::= "verity" | "linear" | ...
For example, the following could be added in the boot parameters:
dm-mod.create="lroot,,,rw, 0 4096 linear 98:16 0, 4096 4096 linear 98:32 0" root=/dev/dm-0
Only the targets that were tested are allowed and the ones that don't
change any block device when the device is create as read-only. For
example, mirror and cache targets are not allowed. The rationale behind
this is that if the user makes a mistake, choosing the wrong device to
be the mirror or the cache can corrupt data.
The only targets initially allowed are:
* crypt
* delay
* linear
* snapshot-origin
* striped
* verity
Co-developed-by: Will Drewry <wad@chromium.org>
Co-developed-by: Kees Cook <keescook@chromium.org>
Co-developed-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Helen Koike <helen.koike@collabora.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
dm supports both, and since we're killing off the legacy path in
general, get rid of it in dm.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The writecache target caches writes on persistent memory or SSD.
It is intended for databases or other programs that need extremely low
commit latency.
The writecache target doesn't cache reads because reads are supposed to
be cached in page cache in normal RAM.
If persistent memory isn't available this target can still be used in
SSD mode.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Colin Ian King <colin.king@canonical.com> # fix missing goto
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> # fix compilation issue with !DAX
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> # use msecs_to_jiffies
Acked-by: Dan Williams <dan.j.williams@intel.com> # reworks to unify ARM and x86 flushing
Signed-off-by: Mike Snitzer <msnitzer@redhat.com>
Change device-mapper's DAX dependency to require the presence of at
least one DAX_DRIVER. This allows device-mapper to be built without
bringing the DAX core along which is especially wasteful when there are
no DAX drivers, like BLK_DEV_PMEM, configured.
Cc: Alasdair Kergon <agk@redhat.com>
Reported-by: Bart Van Assche <Bart.VanAssche@wdc.com>
Reported-by: kbuild test robot <lkp@intel.com>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This device mapper "unstriped" target remaps and unstripes I/O so it
is issued solely on a single drive in a HW RAID0 or dm-striped target.
In a 4 drive HW RAID0 the striped target exposes 1/4th of the LBA range
as a virtual drive. Each I/O to that virtual drive will only be issued
to the 1 drive that was selected of the 4 drives in the HW RAID0.
This unstriped target is most useful for Intel NVMe drives that have
multiple cores but that do not have firmware control to pin separate LBA
ranges to each discrete cpu core.
Signed-off-by: Scott Bauer <scott.bauer@intel.com>
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Acked-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
