NVMe TP 4056 allows controllers to support different command sets.
NVMeoF target currently only supports namespaces that contain
traditional logical blocks that may be randomly read and written. In
some applications there is a value in exposing namespaces that contain
logical blocks that have special access rules (e.g. sequentially write
required namespace such as Zoned Namespace (ZNS)).
In order to support the Zoned Block Devices (ZBD) backend, controllers
need to have support for ZNS Command Set Identifier (CSI).
In this preparation patch, we adjust the code such that it can now
support the default command set identifier. We update the namespace data
structure to store the CSI value which defaults to NVME_CSI_NVM
that represents traditional logical blocks namespace type.
The CSI support is required to implement the ZBD backend for NVMeOF
with host side NVMe ZNS interface, since ZNS commands belong to
the different command set than the default one.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
In current code there exists two backends which are using inline bio
optimization, that adds a duplicate code for freeing the bio.
For Zoned Block Device backend we also use the same optimzation and it
will lead to having duplicate code in the three backends: generic
bdev, passsthru, and generic zns.
Add a helper function to avoid duplicate code and update the respective
backends.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
We report error and complete the request when identify cns value is not
handled in nvmet_execute_identify(). This error reporting is also needed
for Zone Block Device backend for NVMeOF target.
Add a helper nvmet_req_cns_error_compplete() to report an error and
complete the request when idenitfy command cns not handled value.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The block layer provides emulation of zone management operations
targeting all zones of a zoned block device only for the zone reset
operation (REQ_OP_ZONE_RESET). In order to correctly implement
exporting of zoned block devices with NVMeOF, emulating zone management
operations targeting all zones of a device is also necessary for the
open, close and finish zone operations (REQ_OP_ZONE_OPEN,
REQ_OP_ZONE_CLOSE and REQ_OP_ZONE_FINISH).
Instead of duplicating the code, export the existing helper from block
layer so we can use a bio chaining pattern that is present in the block
layer for REQ_OP_ZONE RESET all emulation in the NVMeOF zoned block
device backend.
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
In function errno_to_nvme_status() we store the value of the NVMe
status into the local variable and don't do anything useful with that
but just return.
Remove the local variable and return the value directly from switch.
This also removed extra break statements.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
There is no point in keeping the status variable that is used only once
in the function nvmet_async_events_failall().
Remove the variable and use the value directly.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
In function nvmet_max_nsid() we calculate the max nsid by iterating
over the XArray and store it in the variable nsid that has type of
unsigned long.
Since the value of this function is stored into the subsys->max_nsid
which is of type u32, change the local variable nsid type and the return
type of the same function to u32.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Use u32 type for the nsid_max member of the nvmet_subsys structure.
This avoids the type confusion when updating the subsys->nax_nsid from
ns->nsid. This also matches the nvmet_ns->nsid member.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The function nvmet_file_parse_io_cmd() is called from the fast path. The
local variable to that function cmd is only used once.
Remove the local variable and use req->cmd directly.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The function nvmet_bdev_parse_io_cmd() is called from the fast path.
The local variable to that function cmd is only used once.
Remove the local variable and use req->cmd directly.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Once some host has connected to the nvmf target, make sure that the
version number is stable and cannot be changed.
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Noam Gottlieb <ngottlieb@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Currently, once the subsystem's model_number is set for the first time
there is no way to change it. However, as long as no connection was
established to nvmf target, there is no reason for such restriction and
we should allow to change the subsystem's model_number as many times as
needed.
In addition, in order to simplfy the changes and make the model number
flow more similar to the rest of the attributes in the Identify
Controller data structure, we set a default value for the model number
at the initiation of the subsystem.
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Noam Gottlieb <ngottlieb@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Once some host has connected to the target, make sure that the serial
number is stable and cannot be changed.
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Noam Gottlieb <ngottlieb@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
According to the NVM specification, the serial_number should be 20 bytes
(bytes 23:04 of the Identify Controller data structure), and should
contain only ASCII characters.
In accordance, the serial_number size is changed to 20 bytes and before
any attempt to store a new value in serial_number we check that the
input is valid - i.e. contains only ASCII characters, is not empty and
does not exceed 20 bytes.
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Noam Gottlieb <ngottlieb@nvidia.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
When parsing a request in nvmet_fc_handle_fcp_rqst() we should not
check for invalid target ports; if we do the command is aborted
from the fcp layer, causing the host to assume a transport error.
Rather we should still forward this request to the nvmet layer, which
will then correctly fail the command with an appropriate error status.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Declare and initialize structure variable to the zero values so that we
can get rid of the zeroout memset call.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Declare and initialize structure variable to the zero values so that we
can get rid of the zeroout memset call.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Declare and initialize structure variable to the zero values so that we
can get rid of the zeroout memset call.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Declare and initialize structure variable to the zero values so that we
can get rid of the zeroout memset call.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Use the helper to check NVMe controller's SGL support.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Use the helper to check NVMe controller's SGL support.
Reviewed-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
For various transports such as fc/tcp/pci it is common to check if
NVMe SGLs are supported or not by the controller.
In this preparation patch we add a helper to avoid the open coding of
such checks in the various transport.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Remove the extra white line at the end of the functions.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
nvmeq->cq_head is compared with nvmeq->q_depth and changed the value
and cq_phase for handling the next cq db.
but, nvmeq->q_depth's type is u32 and max. value is 0x10000 when
CQP.MSQE is 0xffff and io_queue_depth is 0x10000.
current temp. variable for comparing with nvmeq->q_depth is overflowed
when previous nvmeq->cq_head is 0xffff.
in this case, nvmeq->cq_phase is not updated.
so, fix data type for temp. variable to u32.
Signed-off-by: JK Kim <jongkang.kim2@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
These error paths currently return success but they should return
-EOPNOTSUPP.
Fixes: 73ffcefcfc ("nvme-tcp: check sgl supported by target")
Fixes: 3f2304f8c6 ("nvme-tcp: add NVMe over TCP host driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Add a helper nvme_validate_passthru_nsid() to validate the nsid that
removes the nsid validation and error message print code from
nvme_user_cmd() and nvme_user_cmd64().
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Fix a singular/plural mismatch in the CONFIG_NVME_MULTIPATH help text.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Commit ce86dad222 ("nvme-multipath: reset bdev to ns head when
failover") moved the reset code where the bio is added to the
requeue_list for the failover path. But it left the original
bio_set_dev in nvme_requeue_work.
There is a second path to nvme_requee_work. It is via
nvme_ns_head_submit_bio. Though we don't have to set bio->bi_bdev for
this path either, as it points to the correct bdev already.
Let's remove the bio_set_dev. It's updating the bio->bi_bdev with the
same pointer and thus it's unnecessary.
Signed-off-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The controller is required to have a non-zero MNAN value if it supports
ANA:
If the controller supports Asymmetric Namespace Access Reporting, then
this field shall be set to a non-zero value that is less than or equal
to the NN value.
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
AMD systems from Renoir and Lucienne require that the NVME controller
is put into D3 over a Modern Standby / suspend-to-idle
cycle. This is "typically" accomplished using the `StorageD3Enable`
property in the _DSD, but this property was introduced after many
of these systems launched and most OEM systems don't have it in
their BIOS.
On AMD Renoir without these drives going into D3 over suspend-to-idle
the resume will fail with the NVME controller being reset and a trace
like this in the kernel logs:
```
[ 83.556118] nvme nvme0: I/O 161 QID 2 timeout, aborting
[ 83.556178] nvme nvme0: I/O 162 QID 2 timeout, aborting
[ 83.556187] nvme nvme0: I/O 163 QID 2 timeout, aborting
[ 83.556196] nvme nvme0: I/O 164 QID 2 timeout, aborting
[ 95.332114] nvme nvme0: I/O 25 QID 0 timeout, reset controller
[ 95.332843] nvme nvme0: Abort status: 0x371
[ 95.332852] nvme nvme0: Abort status: 0x371
[ 95.332856] nvme nvme0: Abort status: 0x371
[ 95.332859] nvme nvme0: Abort status: 0x371
[ 95.332909] PM: dpm_run_callback(): pci_pm_resume+0x0/0xe0 returns -16
[ 95.332936] nvme 0000:03:00.0: PM: failed to resume async: error -16
```
The Microsoft documentation for StorageD3Enable mentioned that Windows has
a hardcoded allowlist for D3 support, which was used for these platforms.
Introduce quirks to hardcode them for Linux as well.
As this property is now "standardized", OEM systems using AMD Cezanne and
newer APU's have adopted this property, and quirks like this should not be
necessary.
CC: Shyam-sundar S-k <Shyam-sundar.S-k@amd.com>
CC: Alexander Deucher <Alexander.Deucher@amd.com>
CC: Prike Liang <prike.liang@amd.com>
Link: https://docs.microsoft.com/en-us/windows-hardware/design/component-guidelines/power-management-for-storage-hardware-devices-intro
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Julian Sikorski <belegdol@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Although first implemented for NVME, this check may be usable by
other drivers as well. Microsoft's specification explicitly mentions
that is may be usable by SATA and AHCI devices. Google also indicates
that they have used this with SDHCI in a downstream kernel tree that
a user can plug a storage device into.
Link: https://docs.microsoft.com/en-us/windows-hardware/design/component-guidelines/power-management-for-storage-hardware-devices-intro
Suggested-by: Keith Busch <kbusch@kernel.org>
CC: Shyam-sundar S-k <Shyam-sundar.S-k@amd.com>
CC: Alexander Deucher <Alexander.Deucher@amd.com>
CC: Rafael J. Wysocki <rjw@rjwysocki.net>
CC: Prike Liang <prike.liang@amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Pull MD changes from Song:
"1) iostats rewrite by Guoqing Jiang;
2) raid5 lock contention optimization by Gal Ofri."
* 'md-next' of https://git.kernel.org/pub/scm/linux/kernel/git/song/md:
md/raid5: avoid device_lock in read_one_chunk()
md: add comments in md_integrity_register
md: check level before create and exit io_acct_set
md: Constify attribute_group structs
md: mark some personalities as deprecated
md/raid10: enable io accounting
md/raid1: enable io accounting
md/raid1: rename print_msg with r1bio_existed
md/raid5: avoid redundant bio clone in raid5_read_one_chunk
md/raid5: move checking badblock before clone bio in raid5_read_one_chunk
md: add io accounting for raid0 and raid5
md: revert io stats accounting
Two oneliners to fix clang warnings:
- -Wimplicit-fallthrough warning fix from Gustavo A. R. Silva.
- Redundant assignment warning fix from Jiapeng Chong.
No semantic and behavioural changes.
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Merge tag 'floppy-for-5.14' of https://github.com/evdenis/linux-floppy into for-5.14/drivers
Pull floppy fixes from Denis:
"Floppy patches for 5.14
Two oneliners to fix clang warnings:
- -Wimplicit-fallthrough warning fix from Gustavo A. R. Silva.
- Redundant assignment warning fix from Jiapeng Chong.
No semantic and behavioural changes."
* tag 'floppy-for-5.14' of https://github.com/evdenis/linux-floppy:
floppy: Fix fall-through warning for Clang
floppy: cleanup: remove redundant assignment to nr_sectors
Variable nr_sectors is set to zero but this value is never
read as it is overwritten later on, hence it is a redundant
assignment and can be removed.
Clean up the following clang-analyzer warning:
drivers/block/floppy.c:2333:2: warning: Value stored to 'nr_sectors' is
never read [clang-analyzer-deadcode.DeadStores].
Link: https://lore.kernel.org/r/1619774805-121562-1-git-send-email-jiapeng.chong@linux.alibaba.com
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Denis Efremov <efremov@linux.com>
There is a lock contention on device_lock in read_one_chunk().
device_lock is taken to sync conf->active_aligned_reads and
conf->quiesce.
read_one_chunk() takes the lock, then waits for quiesce=0 (resumed)
before incrementing active_aligned_reads.
raid5_quiesce() takes the lock, sets quiesce=2 (in-progress), then waits
for active_aligned_reads to be zero before setting quiesce=1
(suspended).
Introduce a fast (lockless) path in read_one_chunk(): activate aligned
read without taking device_lock. In case quiesce starts while
activating the aligned-read in fast path, deactivate it and revert to
old behavior (take device_lock and wait for quiesce to finish).
Add smp store/load in raid5_quiesce()/read_one_chunk() respectively to
gaurantee that read_one_chunk() does not miss an ongoing quiesce.
My setups:
1. 8 local nvme drives (each up to 250k iops).
2. 8 ram disks (brd).
Each setup with raid6 (6+2), 1024 io threads on a 96 cpu-cores (48 per
socket) system. Record both iops and cpu spent on this contention with
rand-read-4k. Record bw with sequential-read-128k. Note: in most cases
cpu is still busy but due to "new" bottlenecks.
nvme:
| iops | cpu | bw
-----------------------------------------------
without patch | 1.6M | ~50% | 5.5GB/s
with patch | 2M (throttled) | 0% | 16GB/s (throttled)
ram (brd):
| iops | cpu | bw
-----------------------------------------------
without patch | 2M | ~80% | 24GB/s
with patch | 4M | 0% | 55GB/s
CC: Song Liu <song@kernel.org>
CC: Neil Brown <neilb@suse.de>
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Gal Ofri <gal.ofri@storing.io>
Signed-off-by: Song Liu <song@kernel.org>
Given it is not obvious for the error handling, let's try to add some
comments here to make it clear.
Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <song@kernel.org>
The bio_set (io_acct_set) is used by personalities to clone bio and
trace the timestamp of bio. Some personalities such as raid1/10 don't
need the bio_set, so add check to not create it unconditionally.
Also update the comment for md_account_bio to make it more clear.
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <song@kernel.org>
The attribute_group structs are never modified, they're only passed to
sysfs_create_group() and sysfs_remove_group(). Make them const to allow
the compiler to put them in read-only memory.
Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Signed-off-by: Song Liu <song@kernel.org>
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>
For raid10, we record the start time between split bio and clone bio,
and finish the accounting in the final endio.
Also introduce start_time in r10bio accordingly.
Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <song@kernel.org>
For raid1, we record the start time between split bio and clone bio,
and finish the accounting in the final endio.
Also introduce start_time in r1bio accordingly.
Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <song@kernel.org>
The caller of raid1_read_request could pass NULL or a valid pointer for
"struct r1bio *r1_bio", so it actually means whether r1_bio is existed
or not.
Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <song@kernel.org>
After enable io accounting, chunk read bio could be cloned twice which
is not good. To avoid such inefficiency, let's clone align_bio from
io_acct_set too, then we need only call md_account_bio in make_request
unconditionally.
Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <song@kernel.org>
We don't need to clone bio if the relevant region has badblock.
Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <song@kernel.org>
We introduce a new bioset (io_acct_set) for raid0 and raid5 since they
don't own clone infrastructure to accounting io. And the bioset is added
to mddev instead of to raid0 and raid5 layer, because with this way, we
can put common functions to md.h and reuse them in raid0 and raid5.
Also struct md_io_acct is added accordingly which includes io start_time,
the origin bio and cloned bio. Then we can call bio_{start,end}_io_acct
to get related io status.
Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <song@kernel.org>
The commit 41d2d848e5 ("md: improve io stats accounting") could cause
double fault problem per the report [1], and also it is not correct to
change ->bi_end_io if md don't own it, so let's revert it.
And io stats accounting will be replemented in later commits.
[1]. https://lore.kernel.org/linux-raid/3bf04253-3fad-434a-63a7-20214e38cf26@gmail.com/T/#t
Fixes: 41d2d848e5 ("md: improve io stats accounting")
Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <song@kernel.org>
pstore-blk just pokes directly into the pagecache for the block
device without going through the file operations for that by faking
up it's own file operations that do not match the block device ones.
As this breaks the control of the block layer of it's page cache,
and even now just works by accident only the best thing is to just
disable this driver.
Fixes: 17639f67c1 ("pstore/blk: Introduce backend for block devices")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210608161327.1537919-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Fixes scripts/checkpatch.pl warning:
WARNING: Possible unnecessary 'out of memory' message
Remove it can help us save a bit of memory.
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Chaitanya Kulkarni