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2013-12-11OvmfPkg/Virtio: Removed VirtioReadDevice() / VirtIoWriteDevice() functionsOlivier Martin
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
2013-12-11OvmfPkg: Make the VirtIo devices use the new VIRTIO_DEVICE_PROTOCOLOlivier Martin
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
2013-08-23OvmfPkg: Virtio: load used ring element strictly after loading used indexLaszlo Ersek
Enforce in-order execution of these steps even on not sequentially consistent architectures, as discussed in [1]. These changes should be unnecessary on x86 (the only architecture OVMF currently supports), but they align the OVMF virtio code with the virtio specification and could be necessary for future OVMF ports. [1] http://lists.linuxfoundation.org/pipermail/virtualization/2013-June/024547.html Suggested-by: Stefan Hajnoczi <stefanha@redhat.com> Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Jordan Justen <jordan.l.justen@intel.com> git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@14601 6f19259b-4bc3-4df7-8a09-765794883524
2013-05-15OvmfPkg: adapt VirtioFlush()'s leading comment to the coding stylejljusten
Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Laszlo Ersek <lersek@redhat.com> git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@14362 6f19259b-4bc3-4df7-8a09-765794883524
2013-05-15OvmfPkg: adapt VirtioAppendDesc()'s leading comment to the coding stylejljusten
Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Laszlo Ersek <lersek@redhat.com> git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@14361 6f19259b-4bc3-4df7-8a09-765794883524
2013-05-15OvmfPkg: adapt VirtioPrepare()'s leading comment to the coding stylejljusten
Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Laszlo Ersek <lersek@redhat.com> git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@14360 6f19259b-4bc3-4df7-8a09-765794883524
2013-05-14OvmfPkg: VirtioLib: populate the Available Ring correctlyjljusten
The descriptor table (also known as "queue") consists of descriptors. (The corresponding type in the code is VRING_DESC.) An individual descriptor describes a contiguous buffer, to be transferred uni-directionally between host and guest. Several descriptors in the descriptor table can be linked into a descriptor chain, specifying a bi-directional scatter-gather transfer between host and guest. Such a descriptor chain is also known as "virtio request". (The descriptor table can host sereval descriptor chains (in-flight virtio requests) in parallel, but the OVMF driver supports at most one chain, at any point in time.) The first descriptor in any descriptor chain is called "head descriptor". In order to submit a number of parallel requests (= a set of independent descriptor chains) from the guest to the host, the guest must put *only* the head descriptor of each separate chain onto the Available Ring. VirtioLib currently places the head of its one descriptor chain onto the Available Ring repeatedly, once for each single (head *or* dependent) descriptor in said descriptor chain. If the descriptor chain comprises N descriptors, this error amounts to submitting the same entire chain N times in parallel. Available Ring Descriptor table Ptr to head ----> Desc#0 (head of chain) Ptr to head --/ Desc#1 (next in same chain) ... / ... Ptr to head / Desc#(N-1) (last in same chain) Anatomy of a single virtio-blk READ request (a descriptor chain with three descriptors): virtio-blk request header, prepared by guest: VirtioAppendDesc PhysAddr=3FBC6050 Size=16 Flags=1 Head=1232 Next=1232 payload to be filled in by host: VirtioAppendDesc PhysAddr=3B934C00 Size=32768 Flags=3 Head=1232 Next=1233 host status, to be filled in by host: VirtioAppendDesc PhysAddr=3FBC604F Size=1 Flags=2 Head=1232 Next=1234 Processing on the host side -- the descriptor chain is processed three times in parallel (its head is available to virtqueue_pop() thrice); the same chain is submitted/collected separately to/from AIO three times: virtio_queue_notify vdev VDEV vq VQ#0 virtqueue_pop vq VQ#0 elem EL#0 in_num 2 out_num 1 bdrv_aio_readv bs BDRV sector_num 585792 nb_sectors 64 opaque REQ#0 virtqueue_pop vq VQ#0 elem EL#1 in_num 2 out_num 1 bdrv_aio_readv bs BDRV sector_num 585792 nb_sectors 64 opaque REQ#1 virtqueue_pop vq VQ#0 elem EL#2 in_num 2 out_num 1 bdrv_aio_readv bs BDRV sector_num 585792 nb_sectors 64 opaque REQ#2 virtio_blk_rw_complete req REQ#0 ret 0 virtio_blk_req_complete req REQ#0 status 0 virtio_blk_rw_complete req REQ#1 ret 0 virtio_blk_req_complete req REQ#1 status 0 virtio_blk_rw_complete req REQ#2 ret 0 virtio_blk_req_complete req REQ#2 status 0 On my Thinkpad T510 laptop with RHEL-6 as host, this probably leads to simultaneous DMA transfers targeting the same RAM area. Even though the source of each transfer is identical, the data is corrupted in the destination buffer -- the CRC32 calculated over the buffer varies, even though the origin of the transfers is the same, never rewritten LBA. SynchronousRequest Lba=585792 BufSiz=32768 ReqIsWrite=0 Crc32=BF68A44D The problem is invisible on my HP Z400 workstation. Fix the request submission by: - building the only one descriptor chain supported by VirtioLib always at the beginning of the descriptor table, - ensuring the head descriptor of this chain is put on the Available Ring only once, - requesting the virtio spec's language to be cleaned up <http://lists.linuxfoundation.org/pipermail/virtualization/2013-April/024032.html>. Available Ring Descriptor table Ptr to head ----> Desc#0 (head of chain) Desc#1 (next in same chain) ... Desc#(N-1) (last in same chain) VirtioAppendDesc PhysAddr=3FBC6040 Size=16 Flags=1 Head=0 Next=0 VirtioAppendDesc PhysAddr=3B934C00 Size=32768 Flags=3 Head=0 Next=1 VirtioAppendDesc PhysAddr=3FBC603F Size=1 Flags=2 Head=0 Next=2 virtio_queue_notify vdev VDEV vq VQ#0 virtqueue_pop vq VQ#0 elem EL#0 in_num 2 out_num 1 bdrv_aio_readv bs BDRV sector_num 585792 nb_sectors 64 opaque REQ#0 virtio_blk_rw_complete req REQ#0 ret 0 virtio_blk_req_complete req REQ#0 status 0 SynchronousRequest Lba=585792 BufSiz=32768 ReqIsWrite=0 Crc32=1EEB2B07 (The Crc32 was double-checked with edk2's and Linux's guest IDE 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@14356 6f19259b-4bc3-4df7-8a09-765794883524
2012-10-12OvmfPkg: MSVC build fixes for VirtioLib and VirtioBlkDxejljusten
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
2012-10-12OvmfPkg: librarize reusable bits from VirtioBlkDxe's SynchronousRequest()jljusten
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
2012-10-12OvmfPkg: rename AppendDesc to VirtioAppendDescjljusten
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
2012-10-12OvmfPkg: extract VirtioLib from VirtioBlkDxejljusten
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