These defines are applicable to userland too, but virtqueue.h contains
the kernel virtqueue interface, and is therefore not usable in userland.
Note that Linux places these defines in virtio_ring.h, but I don't want
the drivers including this header file to keep the VirtIO ring opaque to
everything but the virtqueue.
MFC after: 1 week
Partial support for the EVENT_IDX feature was added a while ago,
but this commit adds an interface for the device driver to hint
how long (in terms of descriptors) the next interrupt should be
delayed.
The first user of this will be used to reduce VirtIO net's Tx
completion interrupts.
Contains projects/virtio commits:
r245709:
Each VirtIO device was scheduling its own taskqueue(9) to do the
off-level interrupt handling. ithreads(9) is the more nature way
to do this. The primary motivation for this work to better support
network multiqueue.
r245710:
virtio: Change virtqueue intr handlers to return void
r245711:
virtio_blk: Remove interrupt taskqueue
r245721:
vtnet: Remove interrupt taskqueue
r245722:
virtio_scsi: Remove interrupt taskqueue
r245747:
vtnet: Remove taskqueue fields missed in r245721
MFC after: 1 month
PCI:
- Properly handle interrupt fallback from MSIX to MSI to legacy.
The host may not have sufficient resources to support MSIX,
so we must be able to fallback to legacy interrupts.
- Add interface to get the (sub) vendor and device IDs.
- Rename flags to VTPCI_FLAG_* like other VirtIO drivers.
Block:
- No longer allocate vtblk_requests from separate UMA zone.
malloc(9) from M_DEVBUF is sufficient. Assert segment counts
at allocation.
- More verbose error and debug messages.
Network:
- Remove stray write once variable.
Virtqueue:
- Shuffle code around in preparation of converting the mb()s to
the appropriate atomic(9) operations.
- Only walk the descriptor chain when freeing if INVARIANTS is
defined since the result is only KASSERT()ed.
Submitted by: Bryan Venteicher (bryanv@daemoninthecloset.org)
a8af6270bd96be6ccd86f70b60fa6512b710e4f0
virtio_blk: Include function name in panic string
cbdb03a694b76c5253d7ae3a59b9995b9afbb67a
virtio_balloon: Do the notify outside of the lock
By the time we return from virtqueue_notify(), the descriptor
will be in the used ring so we shouldn't have to sleep.
10ba392e60692529a5cbc1e9987e4064e0128447
virtio: Use DEVMETHOD_END
80cbcc4d6552cac758be67f0c99c36f23ce62110
virtqueue: Add support for VIRTIO_F_RING_EVENT_IDX
This can be used to reduce the number of guest/host and
host/guest interrupts by delaying the interrupt until a
certain index value is reached.
Actual use by the network driver will come along later.
8fc465969acc0c58477153e4c3530390db436c02
virtqueue: Simplify virtqueue_nused()
Since the values just wrap naturally at UINT16_MAX, we
can just subtract the two values directly, rather than
doing 2's complement math.
a8aa22f25959e2767d006cd621b69050e7ffb0ae
virtio_blk: Remove debugging crud from 75dd732a
There seems to be an issue with Qemu (or FreeBSD VirtIO) that sets
the PCI register space for the device config to bogus values. This
only seems to happen after unloading and reloading the module.
d404800661cb2a9769c033f8a50b2133934501aa
virtio_blk: Use better variable name
75dd732a97743d96e7c63f7ced3c2169696dadd3
virtio_blk: Partially revert 92ba40e65
Just use the virtqueue to determine if any requests are
still inflight.
06661ed66b7a9efaea240f99f414c368f1bbcdc7
virtio_blk: error if allowed too few segments
Should never happen unless the host provides use with a
bogus seg_max value.
4b33e5085bc87a818433d7e664a0a2c8f56a1a89
virtio_blk: Sort function declarations
426b9f5cac892c9c64cc7631966461514f7e08c6
virtio_blk: Cleanup whitespace
617c23e12c61e3c2233d942db713c6b8ff0bd112
virtio_blk: Call disk_err() on error'd completed requests
081a5712d4b2e0abf273be4d26affcf3870263a9
virtio_blk: ASSERT the ready and inflight request queues are empty
a9be2631a4f770a84145c18ee03a3f103bed4ca8
virtio_blk: Simplify check for too many segments
At the cost of a small style violation.
e00ec09da014f2e60cc75542d0ab78898672d521
virtio_blk: Add beginnings of suspend/resume
Still not sure if we need to virtio_stop()/virtio_reinit()
the device before/after a suspend.
Don't start additional IO when marked as suspending.
47c71dc6ce8c238aa59ce8afd4bda5aa294bc884
virtio_blk: Panic when dealt an unhandled BIO cmd
1055544f90fb8c0cc6a2395f5b6104039606aafe
virtio_blk: Add VQ enqueue/dequeue wrappers
Wrapper functions managed the added/removing to the in-flight
list of requests.
Normally biodone() any completed IO when draining the virtqueue.
92ba40e65b3bb5e4acb9300ece711f1ea8f3f7f4
virtio_blk: Add in-flight list of requests
74f6d260e075443544522c0833dc2712dd93f49b
virtio_blk: Rename VTBLK_FLAG_DETACHING to VTBLK_FLAG_DETACH
7aa549050f6fc6551c09c6362ed6b2a0728956ef
virtio_blk: Finish all BIOs through vtblk_finish_bio()
Also properly set bio_resid in the case of errors. Most geom_disk
providers seem to do the same.
9eef6d0e6f7e5dd362f71ba097f2e2e4c3744882
Added function to translate VirtIO status to error code
ef06adc337f31e1129d6d5f26de6d8d1be27bcd2
Reset dumping flag when given unexpected parameters
393b3e390c644193a2e392220dcc6a6c50b212d9
Added missing VTBLK_LOCK() in dump handler
Obtained from: Bryan Venteicher bryanv at daemoninthecloset dot org
Tested on Qemu/KVM, VirtualBox, and BHyVe.
Currently built as modules-only on i386/amd64. Man pages not yet hooked
up, pending review.
Submitted by: Bryan Venteicher bryanv at daemoninthecloset dot org
Reviewed by: bz
MFC after: 4 weeks or so