Commit Graph

3411 Commits

Author SHA1 Message Date
Chaitanya Kulkarni
46eca4702d nvmet: use req->cmd directly in bdev-ns fast path
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>
2021-06-17 15:51:20 +02:00
Noam Gottlieb
87fd4cc1c0 nvmet: make ver stable once connection established
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>
2021-06-17 15:51:19 +02:00
Noam Gottlieb
0d148efdf0 nvmet: allow mn change if subsys not discovered
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>
2021-06-17 15:51:19 +02:00
Noam Gottlieb
7ae023c5aa nvmet: make sn stable once connection was established
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>
2021-06-17 15:51:19 +02:00
Noam Gottlieb
e13b061589 nvmet: change sn size and check validity
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>
2021-06-17 15:51:19 +02:00
Hannes Reinecke
2a4a910aa4 nvmet-fc: do not check for invalid target port in nvmet_fc_handle_fcp_rqst()
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>
2021-06-17 15:51:19 +02:00
Chaitanya Kulkarni
eff4423ec0 nvme-fabrics: remove memset in connect io q
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>
2021-06-17 15:51:19 +02:00
Chaitanya Kulkarni
bfa9d1222d nvme-fabrics: remove memset in connect admin q
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>
2021-06-17 15:51:19 +02:00
Chaitanya Kulkarni
c22c272013 nvme-fabrics: remove memset in nvmf_reg_write32()
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>
2021-06-17 15:51:19 +02:00
Chaitanya Kulkarni
2796a8e409 nvme-fabrics: remove memset in nvmf_reg_read64()
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>
2021-06-17 15:51:19 +02:00
Chaitanya Kulkarni
3b54064fbc nvme-tcp: use ctrl sgl check helper
Use the helper to check NVMe controller's SGL support.

Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-06-17 15:51:19 +02:00
Chaitanya Kulkarni
253a0b76a1 nvme-pci: use ctrl sgl check helper
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>
2021-06-17 15:51:19 +02:00
Chaitanya Kulkarni
b61678bcd4 nvme-fc: use ctrl sgl check helper
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>
2021-06-17 15:51:18 +02:00
Chaitanya Kulkarni
73eefc270a nvme: add a helper to check ctrl sgl support
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>
2021-06-17 15:51:18 +02:00
Chaitanya Kulkarni
cb1b10e7ac nvme-pci: remove trailing lines for helpers
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>
2021-06-17 15:51:18 +02:00
JK Kim
a0aac973a2 nvme-pci: fix var. type for increasing cq_head
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>
2021-06-17 15:51:18 +02:00
Dan Carpenter
522af60cb2 nvme-tcp: fix error codes in nvme_tcp_setup_ctrl()
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>
2021-06-16 05:36:16 +02:00
Chaitanya Kulkarni
e7d4b5493a nvme: factor out a nvme_validate_passthru_nsid helper
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>
2021-06-16 05:36:16 +02:00
Geert Uytterhoeven
d399742cd0 nvme: fix grammar in the CONFIG_NVME_MULTIPATH kconfig help text
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>
2021-06-16 05:36:15 +02:00
Daniel Wagner
2411424143 nvme: remove superfluous bio_set_dev in nvme_requeue_work
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>
2021-06-16 05:36:15 +02:00
Daniel Wagner
120bb3624d nvme: verify MNAN value if ANA is enabled
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>
2021-06-16 05:36:15 +02:00
Mario Limonciello
2744d7a073 ACPI: Check StorageD3Enable _DSD property in ACPI code
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>
2021-06-16 05:14:59 +02:00
Muneendra Kumar
3dbbca75ed scsi: nvme: Added a new sysfs attribute appid_store
Add a new sysfs attribute, appid_store, which can be used to set the
application identifier in the blkcg associated with a cgroup id.

Below is the interface provided to set the app_id:

  echo "<cgroupid>:<appid>" >> /sys/class/fc/fc_udev_device/appid_store

  echo "457E:100000109b521d27" >> /sys/class/fc/fc_udev_device/appid_store

Link: https://lore.kernel.org/r/20210608043556.274139-4-muneendra.kumar@broadcom.com
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Muneendra Kumar <muneendra.kumar@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-06-10 10:01:32 -04:00
Chaitanya Kulkarni
346ac785ba nvmet: remove a superfluous variable
Remove the superfluous variable "bdev" that is only used once in the
nvmet_bdev_alloc_bip() and use req->ns->bdev that is used everywhere in
the code to access the nvmet request's bdev.

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-06-03 10:29:26 +03:00
Amit Engel
f6e8bd59c4 nvmet: move ka_work initialization to nvmet_alloc_ctrl
Initialize keep-alive work only once, as part of alloc_ctrl
and not each time that nvmet_start_keep_alive_timer is being called

Signed-off-by: Amit Engel <amit.engel@dell.com>
Reviewed-by: Hou Pu <houpu.main@gmail.com>
2021-06-03 10:29:26 +03:00
Christoph Hellwig
f1cf35e17e nvme: remove nvme_{get,put}_ns_from_disk
Now that only one caller is left remove the helpers by restructuring
nvme_pr_command so that it has two helpers for sending a command of to a
given nsid using either the ns_head for multipath, or the namespace
stored in the gendisk.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
2021-06-03 10:29:26 +03:00
Christoph Hellwig
8b4fb0f968 nvme: split nvme_report_zones
Split multipath support out of nvme_report_zones into a separate helper
and simplify the non-multipath version as a result.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
2021-06-03 10:29:26 +03:00
Christoph Hellwig
d8ca66e821 nvme: move the CSI sanity check into nvme_ns_report_zones
Move the CSI check into nvme_ns_report_zones to clean up the code
a little bit and prepare for further refactoring.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
2021-06-03 10:29:25 +03:00
Christoph Hellwig
85b790a7ae nvme: add a sparse annotation to nvme_ns_head_ctrl_ioctl
Add the __releases annotation to tell sparse that nvme_ns_head_ctrl_ioctl
is expected to unlock head->srcu.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
2021-06-03 10:29:25 +03:00
Christoph Hellwig
3e7d1a5516 nvme: open code nvme_put_ns_from_disk in nvme_ns_head_ctrl_ioctl
nvme_ns_head_ctrl_ioctl is always used on multipath nodes, so just call
srcu_read_unlock directly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
2021-06-03 10:29:25 +03:00
Christoph Hellwig
86b4284d98 nvme: open code nvme_{get,put}_ns_from_disk in nvme_ns_head_ioctl
nvme_ns_head_ioctl is always used on multipath nodes, no need to
deal with the de-multiplexers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
2021-06-03 10:29:25 +03:00
Christoph Hellwig
f423c85cd3 nvme: open code nvme_put_ns_from_disk in nvme_ns_head_chr_ioctl
nvme_ns_head_chr_ioctl is always used on multipath nodes, so just call
srcu_read_unlock and consolidate the two unlock paths.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
2021-06-03 10:29:25 +03:00
Chaitanya Kulkarni
97ba6931ba nvme-fabrics: remove extra braces
No need to use the braces around ~ operator.

No functionality change in this patch.

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-06-03 10:29:25 +03:00
Chaitanya Kulkarni
6f860c9225 nvme-fabrics: remove an extra comment
Remove the comment at the end of the switch that is not needed as
function is small enough.

No functionality change in this patch.

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-06-03 10:29:25 +03:00
Chaitanya Kulkarni
63d20f54a3 nvme-fabrics: remove extra new lines in the switch
Remove the extra lines in the switch block that is not common practice
in the kernel code.

No functionality change in this patch.

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-06-03 10:29:25 +03:00
Chaitanya Kulkarni
25e1de8c40 nvme-fabrics: fix the kerneldco comment for nvmf_log_connect_error()
Fix the comment style that matches existing code.

No functionality change in this patch.

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-06-03 10:29:24 +03:00
Martin Belanger
3ede8f72a9 nvme-tcp: allow selecting the network interface for connections
In our application, we need a way to force TCP connections to go out a
specific IP interface instead of letting Linux select the interface
based on the routing tables.

Add the 'host-iface' option to allow specifying the interface to use.
When the option host-iface is specified, the driver uses the specified
interface to set the option SO_BINDTODEVICE on the TCP socket before
connecting.

This new option is needed in addtion to the existing host-traddr for
the following reasons:

Specifying an IP interface by its associated IP address is less
intuitive than specifying the actual interface name and, in some cases,
simply doesn't work. That's because the association between interfaces
and IP addresses is not predictable. IP addresses can be changed or can
change by themselves over time (e.g. DHCP). Interface names are
predictable [1] and will persist over time. Consider the following
configuration.

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state ...
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 100.0.0.100/24 scope global lo
       valid_lft forever preferred_lft forever
2: enp0s3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc ...
    link/ether 08:00:27:21:65:ec brd ff:ff:ff:ff:ff:ff
    inet 100.0.0.100/24 scope global enp0s3
       valid_lft forever preferred_lft forever
3: enp0s8: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc ...
    link/ether 08:00:27:4f:95:5c brd ff:ff:ff:ff:ff:ff
    inet 100.0.0.100/24 scope global enp0s8
       valid_lft forever preferred_lft forever

The above is a VM that I configured with the same IP address
(100.0.0.100) on all interfaces. Doing a reverse lookup to identify the
unique interface associated with 100.0.0.100 does not work here. And
this is why the option host_iface is required. I understand that the
above config does not represent a standard host system, but I'm using
this to prove a point: "We can never know how users will configure
their systems". By te way, The above configuration is perfectly fine
by Linux.

The current TCP implementation for host_traddr performs a
bind()-before-connect(). This is a common construct to set the source
IP address on a TCP socket before connecting. This has no effect on how
Linux selects the interface for the connection. That's because Linux
uses the Weak End System model as described in RFC1122 [2]. On the other
hand, setting the Source IP Address has benefits and should be supported
by linux-nvme. In fact, setting the Source IP Address is a mandatory
FedGov requirement (e.g. connection to a RADIUS/TACACS+ server).
Consider the following configuration.

$ ip addr list dev enp0s8
3: enp0s8: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc ...
    link/ether 08:00:27:4f:95:5c brd ff:ff:ff:ff:ff:ff
    inet 192.168.56.101/24 brd 192.168.56.255 scope global enp0s8
       valid_lft 426sec preferred_lft 426sec
    inet 192.168.56.102/24 scope global secondary enp0s8
       valid_lft forever preferred_lft forever
    inet 192.168.56.103/24 scope global secondary enp0s8
       valid_lft forever preferred_lft forever
    inet 192.168.56.104/24 scope global secondary enp0s8
       valid_lft forever preferred_lft forever

Here we can see that several addresses are associated with interface
enp0s8. By default, Linux always selects the default IP address,
192.168.56.101, as the source address when connecting over interface
enp0s8. Some users, however, want the ability to specify a different
source address (e.g., 192.168.56.102, 192.168.56.103, ...). The option
host_traddr can be used as-is to perform this function.

In conclusion, I believe that we need 2 options for TCP connections.
One that can be used to specify an interface (host-iface). And one that
can be used to set the source address (host-traddr). Users should be
allowed to use one or the other, or both, or none. Of course, the
documentation for host_traddr will need some clarification. It should
state that when used for TCP connection, this option only sets the
source address. And the documentation for host_iface should say that
this option is only available for TCP connections.

References:
[1] https://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames/
[2] https://tools.ietf.org/html/rfc1122

Tested both IPv4 and IPv6 connections.

Signed-off-by: Martin Belanger <martin.belanger@dell.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-06-03 10:29:24 +03:00
Mario Limonciello
e21e0243e7 nvme-pci: look for StorageD3Enable on companion ACPI device instead
The documentation around the StorageD3Enable property hints that it
should be made on the PCI device.  This is where newer AMD systems set
the property and it's required for S0i3 support.

So rather than look for nodes of the root port only present on Intel
systems, switch to the companion ACPI device for all systems.
David Box from Intel indicated this should work on Intel as well.

Link: https://lore.kernel.org/linux-nvme/YK6gmAWqaRmvpJXb@google.com/T/#m900552229fa455867ee29c33b854845fce80ba70
Link: https://docs.microsoft.com/en-us/windows-hardware/design/component-guidelines/power-management-for-storage-hardware-devices-intro
Fixes: df4f9bc4fb ("nvme-pci: add support for ACPI StorageD3Enable property")
Suggested-by: Liang Prike <Prike.Liang@amd.com>
Acked-by: Raul E Rangel <rrangel@chromium.org>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: David E. Box <david.e.box@linux.intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-06-03 10:29:24 +03:00
Alexey Bogoslavsky
ebd8a93aa4 nvme: extend and modify the APST configuration algorithm
The algorithm that was used until now for building the APST configuration
table has been found to produce entries with excessively long ITPT
(idle time prior to transition) for devices declaring relatively long
entry and exit latencies for non-operational power states. This leads
to unnecessary waste of power and, as a result, failure to pass
mandatory power consumption tests on Chromebook platforms.

The new algorithm is based on two predefined ITPT values and two
predefined latency tolerances. Based on these values, as well as on
exit and entry latencies reported by the device, the algorithm looks
for up to 2 suitable non-operational power states to use as primary
and secondary APST transition targets. The predefined values are
supplied to the nvme driver as module parameters:

 - apst_primary_timeout_ms (default: 100)
 - apst_secondary_timeout_ms (default: 2000)
 - apst_primary_latency_tol_us (default: 15000)
 - apst_secondary_latency_tol_us (default: 100000)

The algorithm echoes the approach used by Intel's and Microsoft's drivers
on Windows. The specific default parameter values are also based on those
drivers. Yet, this patch doesn't introduce the ability to dynamically
regenerate the APST table in the event of switching the power source from
AC to battery and back. Adding this functionality may be considered in the
future. In the meantime, the timeouts and tolerances reflect a compromise
between values used by Microsoft for AC and battery scenarios.

In most NVMe devices the new algorithm causes them to implement a more
aggressive power saving policy. While beneficial in most cases, this
sometimes comes at the price of a higher IO processing latency in certain
scenarios as well as at the price of a potential impact on the drive's
endurance (due to more frequent context saving when entering deep non-
operational states). So in order to provide a fallback for systems where
these regressions cannot be tolerated, the patch allows to revert to
the legacy behavior by setting either apst_primary_timeout_ms or
apst_primary_latency_tol_us parameter to 0. Eventually (and possibly after
fine tuning the default values of the module parameters) the legacy behavior
can be removed.

TESTING.

The new algorithm has been extensively tested. Initially, simulations were
used to compare APST tables generated by old and new algorithms for a wide
range of devices. After that, power consumption, performance and latencies
were measured under different workloads on devices from multiple vendors
(WD, Intel, Samsung, Hynix, Kioxia). Below is the description of the tests
and the findings.

General observations.
The effect the patch has on the APST table varies depending on the entry and
exit latencies advertised by the devices. For some devices, the effect is
negligible (e.g. Kioxia KBG40ZNS), for some significant, making the
transitions to PS3 and PS4 much quicker (e.g. WD SN530, Intel 760P), or making
the sleep deeper, PS4 rather than PS3 after a similar amount of time (e.g.
SK Hynix BC511). For some devices (e.g. Samsung PM991) the effect is mixed:
the initial transition happens after a longer idle time, but takes the device
to a lower power state.

Workflows.
In order to evaluate the patch's effect on the power consumption and latency,
7 workflows were used for each device. The workflows were designed to test
the scenarios where significant differences between the old and new behaviors
are most likely. Each workflow was tested twice: with the new and with the
old APST table generation implementation. Power consumption, performance and
latency were measured in the process. The following workflows were used:
1) Consecutive write at the maximum rate with IO depth of 2, with no pauses
2) Repeated pattern of 1000 consecutive writes of 4K packets followed by 50ms
   idle time
3) Repeated pattern of 1000 consecutive writes of 4K packets followed by 150ms
   idle time
4) Repeated pattern of 1000 consecutive writes of 4K packets followed by 500ms
   idle time
5) Repeated pattern of 1000 consecutive writes of 4K packets followed by 1.5s
   idle time
6) Repeated pattern of 1000 consecutive writes of 4K packets followed by 5s
   idle time
7) Repeated pattern of a single random read of a 4K packet followed by 150ms
   idle time

Power consumption
Actual power consumption measurements produced predictable results in
accordance with the APST mechanism's theory of operation.
Devices with long entry and exit latencies such as WD SN530 showed huge
improvement on scenarios 4,5 and 6 of up to 62%. Devices such as Kioxia
KBG40ZNS where the resulting APST table looks virtually identical with
both legacy and new algorithms, showed little or no change in the average power
consumption on all workflows. Devices with extra short latencies such as
Samsung PM991 showed moderate increase in power consumption of up to 18% in
worst case scenarios.
In addition, on Intel and Samsung devices a more complex impact was observed
on scenarios 3, 4 and 7. Our understanding is that due to longer stay in deep
non-operational states between the writes the devices start performing background
operations leading to an increase of power consumption. With the old APST tables
part of these operations are delayed until the scenario is over and a longer idle
period begins, but eventually this extra power is consumed anyway.

Performance.
In terms of performance measured on sustained write or read scenarios, the
effect of the patch is minimal as in this case the device doesn't enter low power
states.

Latency
As expected, in devices where the patch causes a more aggressive power saving
policy (e.g. WD SN530, Intel 760P), an increase in latency was observed in
certain scenarios. Workflow number 7, specifically designed to simulate the
worst case scenario as far as latency is concerned, indeed shows a sharp
increase in average latency (~2ms -> ~53ms on Intel 760P and 0.6 -> 10ms on
WD SN530). The latency increase on other workloads and other devices is much
milder or non-existent.

Signed-off-by: Alexey Bogoslavsky <alexey.bogoslavsky@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-06-03 10:29:24 +03:00
Colin Ian King
13ce7e625a nvme: remove redundant initialization of variable ret
The variable ret is being initialized with a value that is never read,
it is being updated later on. The assignment is redundant and can be
removed.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-06-03 10:29:24 +03:00
Max Gurtovoy
bcd9a0797d nvmet: fix freeing unallocated p2pmem
In case p2p device was found but the p2p pool is empty, the nvme target
is still trying to free the sgl from the p2p pool instead of the
regular sgl pool and causing a crash (BUG() is called). Instead, assign
the p2p_dev for the request only if it was allocated from p2p pool.

This is the crash that was caused:

[Sun May 30 19:13:53 2021] ------------[ cut here ]------------
[Sun May 30 19:13:53 2021] kernel BUG at lib/genalloc.c:518!
[Sun May 30 19:13:53 2021] invalid opcode: 0000 [#1] SMP PTI
...
[Sun May 30 19:13:53 2021] kernel BUG at lib/genalloc.c:518!
...
[Sun May 30 19:13:53 2021] RIP: 0010:gen_pool_free_owner+0xa8/0xb0
...
[Sun May 30 19:13:53 2021] Call Trace:
[Sun May 30 19:13:53 2021] ------------[ cut here ]------------
[Sun May 30 19:13:53 2021]  pci_free_p2pmem+0x2b/0x70
[Sun May 30 19:13:53 2021]  pci_p2pmem_free_sgl+0x4f/0x80
[Sun May 30 19:13:53 2021]  nvmet_req_free_sgls+0x1e/0x80 [nvmet]
[Sun May 30 19:13:53 2021] kernel BUG at lib/genalloc.c:518!
[Sun May 30 19:13:53 2021]  nvmet_rdma_release_rsp+0x4e/0x1f0 [nvmet_rdma]
[Sun May 30 19:13:53 2021]  nvmet_rdma_send_done+0x1c/0x60 [nvmet_rdma]

Fixes: c6e3f13398 ("nvmet: add metadata support for block devices")
Reviewed-by: Israel Rukshin <israelr@nvidia.com>
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-06-02 10:10:38 +03:00
Hannes Reinecke
6622f9acd2 nvme-loop: do not warn for deleted controllers during reset
During concurrent reset and delete calls the reset workqueue is
flushed, causing nvme_loop_reset_ctrl_work() to be executed when
the controller is in state DELETING or DELETING_NOIO.
But this is expected, so we shouldn't issue a WARN_ON here.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-06-02 10:06:53 +03:00
Hannes Reinecke
4237de2f73 nvme-loop: check for NVME_LOOP_Q_LIVE in nvme_loop_destroy_admin_queue()
We need to check the NVME_LOOP_Q_LIVE flag in
nvme_loop_destroy_admin_queue() to protect against duplicate
invocations eg during concurrent reset and remove calls.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-06-02 10:06:53 +03:00
Hannes Reinecke
1c5f8e882a nvme-loop: clear NVME_LOOP_Q_LIVE when nvme_loop_configure_admin_queue() fails
When the call to nvme_enable_ctrl() in nvme_loop_configure_admin_queue()
fails the NVME_LOOP_Q_LIVE flag is not cleared.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-06-02 10:06:53 +03:00
Hannes Reinecke
a6c144f3d2 nvme-loop: reset queue count to 1 in nvme_loop_destroy_io_queues()
The queue count is increased in nvme_loop_init_io_queues(), so we
need to reset it to 1 at the end of nvme_loop_destroy_io_queues().
Otherwise the function is not re-entrant safe, and crash will happen
during concurrent reset and remove calls.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-06-02 10:06:53 +03:00
Christoph Hellwig
f165fb89b7 nvme-multipath: convert to blk_alloc_disk/blk_cleanup_disk
Convert the nvme-multipath driver to use the blk_alloc_disk and
blk_cleanup_disk helpers to simplify gendisk and request_queue
allocation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20210521055116.1053587-19-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-01 07:42:23 -06:00
Christoph Hellwig
0d1feb72ff block: automatically enable GENHD_FL_EXT_DEVT
Automatically set the GENHD_FL_EXT_DEVT flag for all disks allocated
without an explicit number of minors.  This is what all new block
drivers should do, so make sure it is the default without boilerplate
code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20210521055116.1053587-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-01 07:42:23 -06:00
Sagi Grimberg
12b2aaadb6 nvme-rdma: fix in-casule data send for chained sgls
We have only 2 inline sg entries and we allow 4 sg entries for the send
wr sge. Larger sgls entries will be chained. However when we build
in-capsule send wr sge, we iterate without taking into account that the
sgl may be chained and still fit in-capsule (which can happen if the sgl
is bigger than 2, but lower-equal to 4).

Fix in-capsule data mapping to correctly iterate chained sgls.

Fixes: 38e1800275 ("nvme-rdma: Avoid preallocating big SGL for data")
Reported-by: Walker, Benjamin <benjamin.walker@intel.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-05-31 09:06:11 +03:00
Sagi Grimberg
aaeadd7075 nvmet: fix false keep-alive timeout when a controller is torn down
Controller teardown flow may take some time in case it has many I/O
queues, and the host may not send us keep-alive during this period.
Hence reset the traffic based keep-alive timer so we don't trigger
a controller teardown as a result of a keep-alive expiration.

Reported-by: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-05-26 16:18:22 +02:00
Hou Pu
25df1acd2d nvmet-tcp: fix inline data size comparison in nvmet_tcp_queue_response
Using "<=" instead "<" to compare inline data size.

Fixes: bdaf132791 ("nvmet-tcp: fix a segmentation fault during io parsing error")
Signed-off-by: Hou Pu <houpu.main@gmail.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-05-26 16:18:22 +02:00