virtio: uapi: Drop __packed attribute in linux/virtio_pci.h

Commit 92792ac752aa ("virtio-pci: Introduce admin command sending function")
added "__packed" structures to UAPI header linux/virtio_pci.h. This triggers
build failures in the consumer userspace applications without proper "definition"
of __packed (e.g., kvmtool build fails).

Moreover, the structures are already packed well, and doesn't need explicit
packing, similar to the rest of the structures in all virtio_* headers. Remove
the __packed attribute.

Fixes: 92792ac752aa ("virtio-pci: Introduce admin command sending function")
Cc: Feng Liu <feliu@nvidia.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Yishai Hadas <yishaih@nvidia.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Jean-Philippe Brucker <jean-philippe@linaro.org>
Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Message-Id: <20240125232039.913606-1-suzuki.poulose@arm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

virtio-pci: Introduce admin commands

Introduces admin commands, as follow:

The "list query" command can be used by the driver to query the
set of admin commands supported by the virtio device.
The "list use" command is used to inform the virtio device which
admin commands the driver will use.
The "legacy common cfg rd/wr" commands are used to read from/write
into the legacy common configuration structure.
The "legacy dev cfg rd/wr" commands are used to read from/write
into the legacy device configuration structure.
The "notify info" command is used to query the notification region
information.

Signed-off-by: Feng Liu <feliu@nvidia.com>
Reviewed-by: Parav Pandit <parav@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20231219093247.170936-5-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

virtio-pci: Introduce admin command sending function

Add support for sending admin command through admin virtqueue interface.
Abort any inflight admin commands once device reset completes. Activate
admin queue when device becomes ready; deactivate on device reset.

To comply to the below specification statement [1], the admin virtqueue
is activated for upper layer users only after setting DRIVER_OK status.

[1] The driver MUST NOT send any buffer available notifications to the
device before setting DRIVER_OK.

Signed-off-by: Feng Liu <feliu@nvidia.com>
Reviewed-by: Parav Pandit <parav@nvidia.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20231219093247.170936-4-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

virtio-pci: Introduce admin virtqueue

Introduce support for the admin virtqueue. By negotiating
VIRTIO_F_ADMIN_VQ feature, driver detects capability and creates one
administration virtqueue. Administration virtqueue implementation in
virtio pci generic layer, enables multiple types of upper layer
drivers such as vfio, net, blk to utilize it.

Signed-off-by: Feng Liu <feliu@nvidia.com>
Reviewed-by: Parav Pandit <parav@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20231219093247.170936-3-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

virtio_pci: move structure to a header

These are guest/host interfaces, so they belong in the header where e.g.
qemu will know to find them.

Note: we added a new structure as opposed to extending existing one
because someone might be relying on the size of the existing structure
staying unchanged. Add a warning to avoid using sizeof.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>

virtio_pci: struct virtio_pci_common_cfg add queue_reset

Add queue_reset in virtio_pci_modern_common_cfg.

https://github.com/oasis-tcs/virtio-spec/issues/124
https://github.com/oasis-tcs/virtio-spec/issues/139

Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220801063902.129329-30-xuanzhuo@linux.alibaba.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

virtio_pci: struct virtio_pci_common_cfg add queue_notify_data

Add queue_notify_data in struct virtio_pci_common_cfg, which comes from
here https://github.com/oasis-tcs/virtio-spec/issues/89

In order not to affect the API, add a dedicated structure struct
virtio_pci_modern_common_cfg to virtio_pci_modern.h.

Since I want to add queue_reset after queue_notify_data, I submitted
this patch first.

Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220801063902.129329-26-xuanzhuo@linux.alibaba.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

virtio: Implement get_shm_region for PCI transport

On PCI the shm regions are found using capability entries;
find a region by searching for the capability.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: kbuild test robot <lkp@intel.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Cc: kvm@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

Revert "virtio_pci: don't duplicate the msix_enable flag in struct pci_dev"

This reverts commit 53a020c661741f3b87ad3ac6fa545088aaebac9b.

The cleanup seems to be one of the changes that broke
hybernation for some users. We are still not sure why
but revert helps.

Tested-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

virtio_pci: don't duplicate the msix_enable flag in struct pci_dev

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

virtio: define virtio_pci_cfg_cap in header.

We already have VIRTIO_PCI_CAP_PCI_CFG, let's define the structure that
goes with it.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

virtio: define VIRTIO_PCI_CAP_PCI_CFG in header.

This provides backdoor access to the device MMIOs, and every device should
have one. From the virtio 1.0 spec (CS03):

4.1.4.7.1 Device Requirements: PCI configuration access capability

The device MUST present at least one VIRTIO_PCI_CAP_PCI_CFG capability.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Michael S. Tsirkin <mst@redhat.com>

virtio_pci: macros for PCI layout offsets

QEMU wants it, so why not? Trust, but verify.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

virtio_pci: modern driver

Lightly tested against qemu.

One thing *not* implemented here is separate mappings
for descriptor/avail/used rings. That's nice to have,
will be done later after we have core support.

This also exposes the PCI layout to userspace, and
adds macros for PCI layout offsets:

QEMU wants it, so why not? Trust, but verify.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

virtio-pci: define layout for virtio 1.0

Based on patches by Michael S. Tsirkin <mst@redhat.com>, but I found it
hard to follow so changed to use structures which are more
self-documenting.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

virtio_pci: drop virtio_config dependency

virtio_pci does not depend on virtio_config:
let's not include it, users can pull it in as necessary.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

virtio_pci: add VIRTIO_PCI_NO_LEGACY

Add macro to disable all legacy register defines.
Helpful to make sure legacy macros don't leak
through into modern code.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

virtio_pci: better macro exported in uapi

Macro VIRTIO_PCI_CONFIG assumes that userspace actually has a structure
with a field named msix_enabled. Add VIRTIO_PCI_CONFIG_OFF that gets
the msix_enabled by value instead, to make it useful for userspace. We
still keep VIRTIO_PCI_CONFIG around for now, in case some userspace uses
it.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

UAPI: (Scripted) Disintegrate include/linux

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>