summaryrefslogtreecommitdiffstats
path: root/include/linux/virtio.h
Commit message (Collapse)AuthorAgeFilesLines
* virtio: drop thaw PM operationAmit Shah2012-03-311-1/+0
| | | | | | | The thaw operation was used by the balloon driver, but after the last commit there's no reason to have separate thaw and restore callbacks. Signed-off-by: Amit Shah <amit.shah@redhat.com>
* virtio: pci: add PM notification handlers for restore, freeze, thaw, poweroffAmit Shah2012-01-121-0/+5
| | | | | | | | | | | | | | Handle thaw, restore and freeze notifications from the PM core. Expose these to individual virtio drivers that can quiesce and resume vq operations. For drivers not implementing the thaw() method, use the restore method instead. These functions also save device-specific data so that the device can be put in pre-suspend state after resume, and disable and enable the PCI device in the freeze and resume functions, respectively. Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: support unlocked queue kickRusty Russell2012-01-121-0/+4
| | | | | | | | | | | | | | | | | | | | Based on patch by Christoph for virtio_blk speedup: Split virtqueue_kick to be able to do the actual notification outside the lock protecting the virtqueue. This patch was originally done by Stefan Hajnoczi, but I can't find the original one anymore and had to recreated it from memory. Pointers to the original or corrections for the commit message are welcome. Stefan's patch was here: https://github.com/stefanha/linux/commit/a6d06644e3a58e57a774e77d7dc34c4a5a2e7496 http://www.spinics.net/lists/linux-virtualization/msg14616.html Third time's the charm! Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: rename virtqueue_add_buf_gfp to virtqueue_add_bufRusty Russell2012-01-121-15/+6
| | | | | | | | | Remove wrapper functions. This makes the allocation type explicit in all callers; I used GPF_KERNEL where it seemed obvious, left it at GFP_ATOMIC otherwise. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Reviewed-by: Christoph Hellwig <hch@lst.de>
* virtio: document functions better.Rusty Russell2012-01-121-47/+0
| | | | | | | | | | | The old documentation is left over from when we used a structure with strategy pointers. And move the documentation to the C file as per kernel practice. Though I disagree... Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Reviewed-by: Christoph Hellwig <hch@lst.de>
* virtio.h: correct comment for struct virtio_driverWang Sheng-Hui2011-11-021-2/+2
| | | | | | | The patch is against 3.0. Signed-off-by: Wang Sheng-Hui <shhuiw@gmail.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* Add ethtool -g support to virtio_netRick Jones2011-10-241-0/+5
| | | | | | | | | | Add support for reporting ring sizes via ethtool -g to the virtio_net driver. Signed-off-by: Rick Jones <rick.jones2@hp.com> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* virtio: add api for delayed callbacksMichael S. Tsirkin2011-05-301-0/+9
| | | | | | | | | | | | | | | | | | | Add an API that tells the other side that callbacks should be delayed until a lot of work has been done. Implement using the new event_idx feature. Note: it might seem advantageous to let the drivers ask for a callback after a specific capacity has been reached. However, as a single head can free many entries in the descriptor table, we don't really have a clue about capacity until get_buf is called. The API is the simplest to implement at the moment, we'll see what kind of hints drivers can pass when there's more than one user of the feature. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: add_buf_gfpMichael S. Tsirkin2010-05-191-5/+17
| | | | | | | | Add an add_buf variant that gets gfp parameter. Use that to allocate indirect buffers. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio_ring: remove a level of indirectionMichael S. Tsirkin2010-05-191-53/+18
| | | | | | | | | | | We have a single virtqueue_ops implementation, and it seems unlikely we'll get another one at this point. So let's remove an unnecessary level of indirection: it would be very easy to re-add it if another implementation surfaces. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: add virtqueue_ vq_ops wrappersMichael S. Tsirkin2010-05-191-0/+34
| | | | | | | Add inline functions that wrap vq->vq_ops-> calls Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* net/9p: Add sysfs mount_tag file for virtio 9P deviceAneesh Kumar K.V2010-03-131-0/+1
| | | | | | | | | | | | This adds a new file for virtio 9P device. The file contain details of the mount device name that should be used to mount the 9P file system. Ex: /sys/devices/virtio-pci/virtio1/mount_tag file now contian the tag name to be used to mount the 9P file system. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
* virtio: Add ability to detach unused buffers from vringsShirley Ma2010-02-241-0/+4
| | | | | | | | | | | There's currently no way for a virtio driver to ask for unused buffers, so it has to keep a list itself to reclaim them at shutdown. This is redundant, since virtio_ring stores that information. So add a new hook to do this. Signed-off-by: Shirley Ma <xma@us.ibm.com> Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: make add_buf return capacity remainingRusty Russell2009-09-231-1/+1
| | | | | | | | | | This API change means that virtio_net can tell how much capacity remains for buffers. It's necessarily fuzzy, since VIRTIO_RING_F_INDIRECT_DESC means we can fit any number of descriptors in one, *if* we can kmalloc. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dinesh Subhraveti <dineshs@us.ibm.com>
* virtio: add names to virtqueue struct, mapping from devices to queues.Rusty Russell2009-06-121-4/+8
| | | | | | | | | Add a linked list of all virtqueues for a virtio device: this helps for debugging and is also needed for upcoming interface change. Also, add a "name" field for clearer debug messages. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: fix obsolete documentation on probe functionRusty Russell2009-06-121-2/+1
| | | | Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: explicit advertisement of driver featuresRusty Russell2008-05-021-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | A recent proposed feature addition to the virtio block driver revealed some flaws in the API: in particular, we assume that feature negotiation is complete once a driver's probe function returns. There is nothing in the API to require this, however, and even I didn't notice when it was violated. So instead, we require the driver to specify what features it supports in a table, we can then move the feature negotiation into the virtio core. The intersection of device and driver features are presented in a new 'features' bitmap in the struct virtio_device. Note that this highlights the difference between Linux unsigned-long bitmaps where each unsigned long is in native endian, and a straight-forward little-endian array of bytes. Drivers can still remove feature bits in their probe routine if they really have to. API changes: - dev->config->feature() no longer gets and acks a feature. - drivers should advertise their features in the 'feature_table' field - use virtio_has_feature() for extra sanity when checking feature bits Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: remove overzealous BUG_ON.Rusty Russell2008-04-071-1/+4
| | | | | | | | | | | | | | | | The 'disable_cb' callback is designed as an optimization to tell the host we don't need callbacks now. As it is not reliable, the debug check is overzealous: it can happen on two CPUs at the same time. Document this. Even if it were reliable, the virtio_net driver doesn't disable callbacks on transmit so the START_USE/END_USE debugging reentrance protection can be easily tripped even on UP. Thanks to Balaji Rao for the bug report and testing. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> CC: Balaji Rao <balajirrao@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* virtio: fix race in enable_cbChristian Borntraeger2008-03-171-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is a race in virtio_net, dealing with disabling/enabling the callback. I saw the following oops: kernel BUG at /space/kvm/drivers/virtio/virtio_ring.c:218! illegal operation: 0001 [#1] SMP Modules linked in: sunrpc dm_mod CPU: 2 Not tainted 2.6.25-rc1zlive-host-10623-gd358142-dirty #99 Process swapper (pid: 0, task: 000000000f85a610, ksp: 000000000f873c60) Krnl PSW : 0404300180000000 00000000002b81a6 (vring_disable_cb+0x16/0x20) R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:0 CC:3 PM:0 EA:3 Krnl GPRS: 0000000000000001 0000000000000001 0000000010005800 0000000000000001 000000000f3a0900 000000000f85a610 0000000000000000 0000000000000000 0000000000000000 000000000f870000 0000000000000000 0000000000001237 000000000f3a0920 000000000010ff74 00000000002846f6 000000000fa0bcd8 Krnl Code: 00000000002b819a: a7110001 tmll %r1,1 00000000002b819e: a7840004 brc 8,2b81a6 00000000002b81a2: a7f40001 brc 15,2b81a4 >00000000002b81a6: a51b0001 oill %r1,1 00000000002b81aa: 40102000 sth %r1,0(%r2) 00000000002b81ae: 07fe bcr 15,%r14 00000000002b81b0: eb7ff0380024 stmg %r7,%r15,56(%r15) 00000000002b81b6: a7f13e00 tmll %r15,15872 Call Trace: ([<000000000fa0bcd0>] 0xfa0bcd0) [<00000000002b8350>] vring_interrupt+0x5c/0x6c [<000000000010ab08>] do_extint+0xb8/0xf0 [<0000000000110716>] ext_no_vtime+0x16/0x1a [<0000000000107e72>] cpu_idle+0x1c2/0x1e0 The problem can be triggered with a high amount of host->guest traffic. I think its the following race: poll says netif_rx_complete poll calls enable_cb enable_cb opens the interrupt mask a new packet comes, an interrupt is triggered----\ enable_cb sees that there is more work | enable_cb disables the interrupt | . V . interrupt is delivered . skb_recv_done does atomic napi test, ok some waiting disable_cb is called->check fails->bang! . poll would do napi check poll would do disable_cb The fix is to let enable_cb not disable the interrupt again, but expect the caller to do the cleanup if it returns false. In that case, the interrupt is only disabled, if the napi test_set_bit was successful. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (cleaned up doco)
* virtio: reset functionRusty Russell2008-02-041-5/+0
| | | | | | | | | | | | | | | | | | | | | A reset function solves three problems: 1) It allows us to renegotiate features, eg. if we want to upgrade a guest driver without rebooting the guest. 2) It gives us a clean way of shutting down virtqueues: after a reset, we know that the buffers won't be used by the host, and 3) It helps the guest recover from messed-up drivers. So we remove the ->shutdown hook, and the only way we now remove feature bits is via reset. We leave it to the driver to do the reset before it deletes queues: the balloon driver, for example, needs to chat to the host in its remove function. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: configuration change callbackRusty Russell2008-02-041-0/+3
| | | | | | | | | | Various drivers want to know when their configuration information changes: the balloon driver is the immediate user, but the network driver may one day have a "carrier" status as well. This introduces that callback (lguest doesn't use it yet). Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* virtio: explicit enable_cb/disable_cb rather than callback return.Rusty Russell2008-02-041-5/+6
| | | | | | | | | | It seems that virtio_net wants to disable callbacks (interrupts) before calling netif_rx_schedule(), so we can't use the return value to do so. Rename "restart" to "cb_enable" and introduce "cb_disable" hook: callback now returns void, rather than a boolean. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* Virtio interfaceRusty Russell2007-10-231-0/+110
This attempts to implement a "virtual I/O" layer which should allow common drivers to be efficiently used across most virtual I/O mechanisms. It will no-doubt need further enhancement. The virtio drivers add buffers to virtio queues; as the buffers are consumed the driver "interrupt" callbacks are invoked. There is also a generic implementation of config space which drivers can query to get setup information from the host. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> Cc: Arnd Bergmann <arnd@arndb.de>
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-04 08:22:29 +0000