Commit Graph

23 Commits

Author SHA1 Message Date
Laszlo Ersek 8bc951a264 OvmfPkg: VirtioFlush(): return the number of bytes written by the host
VirtioLib provides an API for simple, synchronous (request/response-style)
virtio communication. The guest driver builds one descriptor chain, link
for link, with VirtioPrepare() and VirtioAppendDesc(), then submits the
chain, and awaits the processing, with VirtioFlush().

The descriptor chain is always built at the beginning of the descriptor
area, with the head descriptor having descriptor index 0.

In order to submit the descriptor chain to the host, the guest always
pushes a new "available element" to the Available Ring, in genuine
queue-like fashion, with the new element referencing the head descriptor
(which always has index 0, see above).

In turn, after processing, the host always pushes a new "used element" to
the Used Ring, in genuine queue-like fashion, with the new element
referencing the head descriptor of the chain that was just processed. The
same element also reports the number of bytes that the host wrote,
consecutively across the host-writeable buffers that were linked by the
descriptors.

(See "OvmfPkg/VirtioNetDxe/TechNotes.txt" for a diagram about the
descriptor area and the rings.)

Because at most one descriptor chain can be in flight with VirtioLib at
any time,

- the Available Ring and the Used Ring proceed in lock-step,

- and the head descriptor that the new "available" and "used" elements can
  ever reference has index 0.

Based on the above, we can modify VirtioFlush() to return the number of
bytes written by the host across the descriptor chain. The virtio-block
and virtio-scsi drivers don't care (they have other ways to parse the data
produced by the host), while the virtio-net driver doesn't use
VirtioFlush() at all (it employs VirtioLib only to set up its rings).

However, the virtio entropy device,  to be covered in the upcoming
patches, reports the amount of randomness produced by the host only
through this quantity.

Cc: Jordan Justen <jordan.l.justen@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
2016-02-24 12:07:32 +01:00
Laszlo Ersek fcb636ea42 OvmfPkg: VirtioBlkDxe: reset device at ExitBootServices()
(1) VirtioLib allocates the virtio ring in EfiBootServicesData memory.
    (This is intentional.) Code that executes after ExitBootServices() is
    permitted to reuse such memory.

(2) The hypervisor is allowed to look at, and act upon, a live virtio ring
    at any time, even without explicit virtio kicks from the guest.

Should boot loader code or kernel code, running between ExitBootServices()
and the kernel's own virtio drivers resetting the device, overwrite the
pages that used to contain the virtio ring before ExitBootServices(), QEMU
could theoretically interpret that unrelated data as garbage ring
contents, and abort the guest.

Although we have seen no such reports, better be prudent and reset the
device in an ExitBootServices() event handler. Among other things, this
causes QEMU to forget about the device's virtio ring.

Cc: Jordan Justen <jordan.l.justen@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18624 6f19259b-4bc3-4df7-8a09-765794883524
2015-10-16 19:52:24 +00:00
Jordan Justen c404616199 OvmfPkg: Fix VS2005 build warnings
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16171 6f19259b-4bc3-4df7-8a09-765794883524
2014-09-25 02:29:10 +00:00
Laszlo Ersek 957914ee65 OvmfPkg: VirtioBlkInit(): log topology attributes
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@15005 6f19259b-4bc3-4df7-8a09-765794883524
2013-12-18 19:57:57 +00:00
Laszlo Ersek 6476804e3c OvmfPkg: VirtioBlkInit(): expose virtio-blk topology in BlockIo
UEFI spec                                virtio spec
=======================================  =================================
LowestAlignedLba EFI_LBA (UINT64)        alignment_offset u8
+--------------------------------------  +--------------------------------
| first LBA that is aligned to a         | offset of first aligned
| physical block boundary (SCSI          | logical block
| definition)

LogicalBlocksPerPhysicalBlock UINT32     physical_block_exp u8
+--------------------------------------  +--------------------------------
| number of logical blocks per           | # of logical blocks per
| physical block [...] does not contain  | physical block (log2)
| an exponential value

OptimalTransferLengthGranularity UINT32  opt_io_size le32
+--------------------------------------  +--------------------------------
| optimal transfer length granularity    | optimal (suggested maximum) I/O
| as a number of logical blocks [...] A  | size in blocks
| value of 0 means there is no reported
| optimal transfer length granularity

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@15004 6f19259b-4bc3-4df7-8a09-765794883524
2013-12-18 19:57:46 +00:00
Laszlo Ersek 21479c3c80 OvmfPkg/VirtioBlkDxe/VirtioBlk.c: rewrap overlong lines
Lines should be no longer than 79 characters.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@15003 6f19259b-4bc3-4df7-8a09-765794883524
2013-12-18 19:57:36 +00:00
Laszlo Ersek 71914406e8 OvmfPkg: Virtio drivers: fix incorrect casts in init functions
The recent patch

  OvmfPkg: Make the VirtIo devices use the new VIRTIO_DEVICE_PROTOCOL

was fixed up at commit time, in order to silence warnings issued by the
Visual Studio compiler. Differences between the posted and committed
patch:

>  diff --git a/OvmfPkg/VirtioBlkDxe/VirtioBlk.c b/OvmfPkg/VirtioBlkDxe/VirtioBlk.c
> -index 17b9f71..96a0d9f 100644
> +index 17b9f71..f09b0d1 100644
>  --- a/OvmfPkg/VirtioBlkDxe/VirtioBlk.c
>  +++ b/OvmfPkg/VirtioBlkDxe/VirtioBlk.c
>  @@ -23,7 +23,6 @@
> @@ -994,7 +998,7 @@
>  +  // step 4c -- Report GPFN (guest-physical frame number) of queue.
>  +  //
>  +  Status = Dev->VirtIo->SetQueueAddress (Dev->VirtIo,
> -+      (UINTN) Dev->Ring.Base >> EFI_PAGE_SHIFT);
> ++      (UINT32)(UINTN) Dev->Ring.Base >> EFI_PAGE_SHIFT);
>  +  if (EFI_ERROR (Status)) {
>  +    goto ReleaseQueue;
>  +  }
> @@ -1495,7 +1499,7 @@
>         goto Exit;
>       }
>  diff --git a/OvmfPkg/VirtioNetDxe/SnpInitialize.c b/OvmfPkg/VirtioNetDxe/SnpInitialize.c
> -index 6cee014..8dcf9da 100644
> +index 6cee014..4203fbd 100644
>  --- a/OvmfPkg/VirtioNetDxe/SnpInitialize.c
>  +++ b/OvmfPkg/VirtioNetDxe/SnpInitialize.c
>  @@ -57,14 +57,15 @@ VirtioNetInitRing (
> @@ -1539,7 +1543,7 @@
>  -  Status = VIRTIO_CFG_WRITE (Dev, Generic.VhdrQueueAddress,
>  -             (UINTN) Ring->Base >> EFI_PAGE_SHIFT);
>  +  Status = Dev->VirtIo->SetQueueAddress (Dev->VirtIo,
> -+      (UINTN) Ring->Base >> EFI_PAGE_SHIFT);
> ++      (UINT32)(UINTN) Ring->Base >> EFI_PAGE_SHIFT);
>     if (EFI_ERROR (Status)) {
>  -    VirtioRingUninit (Ring);
>  +    goto ReleaseQueue;
> @@ -1721,7 +1725,7 @@
>   Exit:
>     gBS->RestoreTPL (OldTpl);
>  diff --git a/OvmfPkg/VirtioScsiDxe/VirtioScsi.c b/OvmfPkg/VirtioScsiDxe/VirtioScsi.c
> -index b836fb3..bcec676 100644
> +index b836fb3..2223c9c 100644
>  --- a/OvmfPkg/VirtioScsiDxe/VirtioScsi.c
>  +++ b/OvmfPkg/VirtioScsiDxe/VirtioScsi.c
>  @@ -38,7 +38,6 @@
> @@ -1908,7 +1912,7 @@
>  +  // step 4c -- Report GPFN (guest-physical frame number) of queue.
>  +  //
>  +  Status = Dev->VirtIo->SetQueueAddress (Dev->VirtIo,
> -+      (UINTN) Dev->Ring.Base >> EFI_PAGE_SHIFT);
> ++      (UINT32)(UINTN) Dev->Ring.Base >> EFI_PAGE_SHIFT);
>     if (EFI_ERROR (Status)) {
>       goto ReleaseQueue;
>     }

These casts are incorrect -- they throw away address bits >=32 before
shifting, which can break the drivers in guests with more than 4GB RAM.

The bug is clearly an artifact of the edk2 coding style, which requires
cast expressions to be written as

  (type) expression

rather than the usual

  (type)expression

The latter correctly reflects that casts have one of the strongest
bindings in C. The former actively obscures that fact. Cf.

  (type) expr1 >> expr2

vs.

  (type)expr1 >> expr2

Make sure we shift before we truncate.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@14970 6f19259b-4bc3-4df7-8a09-765794883524
2013-12-12 17:28:05 +00:00
Olivier Martin ece77e4047 OvmfPkg/Virtio: Removed VirtioReadDevice() / VirtIoWriteDevice() functions
These functions did not provide much more than the new protocol functions
VIRTIO_DEVICE_PROTOCOL.ReadDevice() / VIRTIO_DEVICE_PROTOCOL.WriteDevice().

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Olivier Martin <olivier.martin@arm.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@14968 6f19259b-4bc3-4df7-8a09-765794883524
2013-12-11 16:58:39 +00:00
Olivier Martin 56f65ed838 OvmfPkg: Make the VirtIo devices use the new VIRTIO_DEVICE_PROTOCOL
This change replaces the accesses to the PCI bus from the Block, Scsi and Net drivers by
the use of the new VIRTIO_DEVICE_PROTOCOL protocol that abstracts the transport layer.
It means these drivers can be used on PCI and MMIO transport layer.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Olivier Martin <olivier.martin@arm.com>

v5:
- VirtioFlush(): update comment block in VirtioLib.[hc]; error code is
  propagated from VirtIo->SetQueueNotify().
- VirtioBlkInit(): jump to Failed label if SetPageSize() fails
- VirtioBlkInit(): fixup comment, and add error handling, near
  SetQueueNum() call
- VirtioBlkDriverBindingStart(): remove redundant (always false) check for
  a subsystem device ID different from VIRTIO_SUBSYSTEM_BLOCK_DEVICE;
  VirtioBlkDriverBindingSupported() handles it already
- VirtioNetGetFeatures(): update stale comment block
- VirtioNetGetFeatures(): retrieve MAC address byte for byte (open-coded
  loop)
- VirtioNetDriverBindingStart(): remove redundant (always false) check for
  a subsystem device ID different from VIRTIO_SUBSYSTEM_NETWORK_CARD;
  VirtioNetDriverBindingSupported() handles it already
- VirtioNetInitRing(): call SetQueueNum() and SetQueueAlign() for proper
  MMIO operation
- VirtioNetInitialize(): fix destination error label for when
  SetPageSize() fails
- VirtioScsi.c: fix comment block of VIRTIO_CFG_WRITE()/VIRTIO_CFG_READ()
- VirtioScsiInit(): fix destination error label for when SetPageSize()
  fails
- VirtioScsiInit(): call SetQueueNum() and SetQueueAlign() for proper MMIO
  operation

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@14966 6f19259b-4bc3-4df7-8a09-765794883524
2013-12-11 16:58:22 +00:00
Olivier Martin 43e54972af OvmfPkg: Removed magic values for the Virtio Sub-System ID in the PCI device drivers
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Olivier Martin <olivier.martin@arm.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>



git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@14742 6f19259b-4bc3-4df7-8a09-765794883524
2013-09-30 09:04:22 +00:00
jljusten c8c2e4d613 OvmfPkg: VirtioBlkDriverBindingStop: fix incorrect use of UEFI driver model
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13866 6f19259b-4bc3-4df7-8a09-765794883524
2012-10-18 17:07:24 +00:00
jljusten 389b5518bf OvmfPkg/VirtioBlkDxe: Fix VS2012 IA32 build
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13847 6f19259b-4bc3-4df7-8a09-765794883524
2012-10-14 21:17:33 +00:00
jljusten 2f03f796a4 OvmfPkg: VirtioBlkDxe: fix div & mod of 64-bit dividends on IA32/gcc-4.4
OvmfPkg/VirtioBlkDxe/VirtioBlk.c:667: undefined reference to `__umoddi3'
OvmfPkg/VirtioBlkDxe/VirtioBlk.c:750: undefined reference to `__udivdi3'

These operations would come from libgcc in the IA32 build, but OVMF does not
link against libgcc.

Regression-tested the X64 build with Fedora 18 Alpha XFCE and Windows 8
Consumer Preview guests.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13846 6f19259b-4bc3-4df7-8a09-765794883524
2012-10-14 21:17:20 +00:00
jljusten 9de0355b1a OvmfPkg: MSVC build fixes for VirtioLib and VirtioBlkDxe
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Mike Lee <leemiketw@gmail.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13845 6f19259b-4bc3-4df7-8a09-765794883524
2012-10-12 18:54:52 +00:00
jljusten e371e7e545 OvmfPkg: librarize reusable bits from VirtioBlkDxe's SynchronousRequest()
new VirtioLib functions:
- VirtioPrepare(): prepare for appending descriptors
- VirtioFlush(): submit descriptor chain and await host answer

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13844 6f19259b-4bc3-4df7-8a09-765794883524
2012-10-12 18:54:35 +00:00
jljusten 7fcacd6c92 OvmfPkg: rename AppendDesc to VirtioAppendDesc
AppendDesc() should have a prefix implying its containing library,
VirtioLib. Update its sole client VirtioBlkDxe.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13843 6f19259b-4bc3-4df7-8a09-765794883524
2012-10-12 18:54:17 +00:00
jljusten 263559b872 OvmfPkg: extract VirtioLib from VirtioBlkDxe
Introduce a new library called VirtioLib, for now only collecting the
following reusable functions with as little changes as possible:

- VirtioWrite()
- VirtioRead()
- VirtioRingInit()
- VirtioRingUninit()
- AppendDesc()

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13842 6f19259b-4bc3-4df7-8a09-765794883524
2012-10-12 18:53:58 +00:00
jljusten 6b28fe9ee8 OvmfPkg: Include/IndustryStandard: extract VirtioBlk.h from Virtio.h
Separate virtio-blk related macro and type definitions from generic virtio
related ones. Adapt the virtio-blk driver since it needs the latter too.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13841 6f19259b-4bc3-4df7-8a09-765794883524
2012-10-12 18:53:36 +00:00
jljusten a9624f945e OvmfPkg: rename OFFSET_OF_VHDR() / SIZE_OF_VHDR() to *_OF_VBLK()
since they are in fact virtio-blk specific.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13840 6f19259b-4bc3-4df7-8a09-765794883524
2012-10-12 18:53:20 +00:00
jljusten 55c3443a4f OvmfPkg: regroup virtio config fields into generic & specific structs
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13839 6f19259b-4bc3-4df7-8a09-765794883524
2012-10-12 18:53:06 +00:00
jljusten 045b46e92d OvmfPkg: move VirtioBlkDxe/Virtio.h to Include/IndustryStandard/Virtio.h
This commit consists of:
- a verbatim move ("similarity index 100%" in git parlance),
- an updated #include directive in VirtioBlkDxe/VirtioBlk.h,
- and an OvmfPkg.dec package entry in VirtioBlkDxe/VirtioBlk.inf, so that
  the new include directory is searched.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13836 6f19259b-4bc3-4df7-8a09-765794883524
2012-10-12 18:52:24 +00:00
jljusten 936e3a5dfd OvmfPkg: add inclusion guards to VirtioBlkDxe/VirtioBlk.h
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13835 6f19259b-4bc3-4df7-8a09-765794883524
2012-10-12 18:52:05 +00:00
jljusten fd51d75991 OvmfPkg: introduce virtio-blk driver
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13798 6f19259b-4bc3-4df7-8a09-765794883524
2012-10-08 07:32:59 +00:00