Commit Graph

10 Commits

Author SHA1 Message Date
Dariusz Stojaczyk
9728d6b054 virtio: check if setting status bits succeeded
This is required by the Virtio spec. (3.1 Device Init.)
It will also help us with vhost-user error handling.
set_status() doesn't have a way to return an error, so
its internal failures were silenced until now. When we
exceeded max memory region count (8) we only printed
an error message without failing any SPDK initialization.
This patch fixes that. It also removes not-particularly-
useful comments in virtio_dev_reset().

Change-Id: Ibe0010c493ef4e12e1fdd0a1679bf706f298d97e
Signed-off-by: Dariusz Stojaczyk <dariuszx.stojaczyk@intel.com>
Reviewed-on: https://review.gerrithub.io/405915
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>
2018-03-30 19:34:22 -04:00
Dariusz Stojaczyk
6ccc262022 virtio: remove g_virtio_driver
g_virtio_driver contained just a list of all
Virtio-SCSI devices. It's now being removed for
two reasons:
 * it's backend-specific, doesn't fit a generic virtio lib
 * it's difficult to ensure thread-safety for it

Virtio bdev modules will now manage their Virtio
devices by themselves. Virtio-SCSI has now an internal
device list. (And VirtioBlk module maps devices to
bdevs 1:1, so doesn't need any additional work here.)

Change-Id: I3bc68d76d6904df5c56f00fca7ab387871ecf88f
Signed-off-by: Dariusz Stojaczyk <dariuszx.stojaczyk@intel.com>
Reviewed-on: https://review.gerrithub.io/405179
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>
2018-03-27 00:58:14 -04:00
Dariusz Stojaczyk
face9eb258 virtio: add mb() before checking notify flag
The kernel vhost target enables notifying after processing
each interrupt in a following manner.

 * unset NO_NOTIFY flag
 * mb()
 * check avail ring for slipped requests

And we do the following after issuing each I/O.

 * update avail ring
 * check NO_NOTIFY

If NO_NOTIFY check is reordered and read first, we might read
old `true` value, and avail ring might be updated after the
kernel has already done its check. This easily leads to deadlock.

Change-Id: I6bb4490775dfed6fb2987e97c39b713054ae26ad
Signed-off-by: Dariusz Stojaczyk <dariuszx.stojaczyk@intel.com>
Reviewed-on: https://review.gerrithub.io/396499
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>
2018-02-06 19:27:46 -05:00
Dariusz Stojaczyk
5926647156 virtio: inline internal functions
These didn't make much sense anyway.
Removed them so there's less code

Change-Id: I3247c640b13e5847b5f6d822072b63cad269ac8c
Signed-off-by: Dariusz Stojaczyk <dariuszx.stojaczyk@intel.com>
Reviewed-on: https://review.gerrithub.io/398467
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>
2018-02-06 19:27:46 -05:00
Dariusz Stojaczyk
7f0c2bf4b4 virtio: remove virtio_dev_get_status asserts
virtio_dev_get_status may result in an MMIO read,
which is quite expensive. Removed it to improve
performance on debug builds.

Change-Id: Ibe2d13ad381f02f8d258d630283c14ce20b7a340
Signed-off-by: Dariusz Stojaczyk <dariuszx.stojaczyk@intel.com>
Reviewed-on: https://review.gerrithub.io/398468
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
2018-02-05 19:06:11 -05:00
Dariusz Stojaczyk
fb12bbecd2 virtio: move vdev->name allocation to generic virtio
Previously vdev->name was being allocated/freed
separately in virtio_pci and virtio_user backends.
Now it's all done in generic virtio library and
cleans up some code.

Change-Id: I810e976d09781c0c9b25c6f7fd957a83aad6c7b8
Signed-off-by: Dariusz Stojaczyk <dariuszx.stojaczyk@intel.com>
Reviewed-on: https://review.gerrithub.io/394704
Reviewed-by: <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
2018-01-23 22:49:21 -05:00
Dariusz Stojaczyk
8b94174a4e virtio: fix full-virtqueue handling
Distinguish between "not enough descriptors available"
and "iovcnt > queue depth".

This patch brings back I/O re-queueing for virtio bdev
module. It was temporarily disabled by 451de7e1 [1].

[1] 451de7e1: "virtio: switch to the new virtqueue API"

Change-Id: I4c4f6a6d9d91373ee647ea7cafd53ad999aa6aa2
Signed-off-by: Pawel Wodkowski <pawelx.wodkowski@intel.com>
Signed-off-by: Dariusz Stojaczyk <dariuszx.stojaczyk@intel.com>
Reviewed-on: https://review.gerrithub.io/393447
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
2018-01-03 14:35:36 -05:00
Dariusz Stojaczyk
7755bed389 virtio: split device initialization to separate functions
Previously we used to manually set
vdev->max_queues and called virtio_dev_restart
to go through all virtio init states, negotiate
features and allocate virtqueues. This is,
however, insufficient for Virtio-Blk, where we
e.g. need to check against negotiated multiqueue
flag before deciding how many queues we can use
(reading num_queues field from device config is
forbidden unless VIRTIO_BLK_F_MQ is negotiated).

This patch refactors queue-num related code
and also removes various restrictions. If device
supports less queues than requested, a warning
will be printed during initialization, but
the device will now continue to init normally.

The queue-num negotiation for virtio-user should
be eventually moved to upper layers, but that is
not necessary for now.

Change-Id: I418b56fa62c17b547243422ea077f0d76555bd13
Signed-off-by: Dariusz Stojaczyk <dariuszx.stojaczyk@intel.com>
Reviewed-on: https://review.gerrithub.io/393087
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
2017-12-27 15:13:03 -05:00
Dariusz Stojaczyk
a1ca7a12ff virtio: fix enqueuing zero-length descriptor chains
Previous descriptor chain was being corrupted
by setting invalid vq->req_end (virtio.c:538).

Change-Id: I4b27db02dc990e6af011a1b614e30e3050379e9f
Signed-off-by: Dariusz Stojaczyk <dariuszx.stojaczyk@intel.com>
Reviewed-on: https://review.gerrithub.io/392774
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
2017-12-27 15:13:03 -05:00
Dariusz Stojaczyk
9dde5e5c27 virtio: add new library virtio
Exported lib/bdev/rte_virtio as a separate
library not dependent on bdev.

Virtio is now accessible via spdk_internal/virtio.h.
The header is marked `internal`, as it's
not meant to be used by end users. It's
not handy to handle all backend-specific
(e.g. Virtio-SCSI) logic in a user code.

For now the Virtio interface is publicly
exposed only via bdev_virtio module. We
might want to consider adding a separate,
public Virtio-SCSI library in the future.

Note: this patch doesn't do any changes
to the virtio code. Everything is
moved 1:1.

Change-Id: I805e5d12d265d82b0bc5784c89fbadb81abdb278
Signed-off-by: Dariusz Stojaczyk <dariuszx.stojaczyk@intel.com>
Reviewed-on: https://review.gerrithub.io/388166
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
2017-12-26 13:03:29 -05:00