sbuf_put copies sbuf->ele_size of data, and puts into ring. Currently
this function assumes that data size from caller is no less than
sbuf->ele_size.
But as sbuf->ele_size is usually setup by some sources outside of the HV
(e.g., the service VM), it is not meant to be trusted. So caller should
provide the max length of the data for safety reason. sbuf_put() will
return UINT32_MAX if max_len of data is less than element size.
Additionally, a helper function sbuf_put_many() is added for putting
multiple entries.
Tracked-On: #8547
Signed-off-by: Wu Zhou <wu.zhou@intel.com>
Reviewed-by: Junjie Mao <junjie.mao@intel.com>
This patch creates vm_event support in HV, including:
1. Create vm_event data type.
2. Add vm_event sbuf and its initializer. The sbuf will be allocated by
DM in Service VM. Its page address will then be share to HV through
hypercall.
3. Add an API to send the HV generated event.
Tracked-On: #8547
Signed-off-by: Wu Zhou <wu.zhou@intel.com>
Reviewed-by: Junjie Mao <junjie.mao@intel.com>
For an IO request, hv will check if it was registered in asyncio desc
list. If yes, put the corresponding fd to the shared buffer. If the
shared buffer is full, yield the vcpu and try again later.
Tracked-On: #8209
Signed-off-by: Conghui <conghui.chen@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
Current IO emulation is synchronous. The user VM need to wait for the
completion of the the I/O request before return. But Virtio Spec
introduces introduces asynchronous IO with a new register in MMIO/PIO
space named NOTIFY, to be used for FE driver to notify BE driver, ACRN
hypervisor can emulate this register by sending a notification to vCPU
in Service VM side. This way, FE side can resume to work without waiting
for the full completion of BE side response.
Tracked-On: #8209
Signed-off-by: Conghui <conghui.chen@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
Extend sbuf hypercall to support other kinds of share buffer.
Tracked-On: #8209
Signed-off-by: Conghui <conghui.chen@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
sbuf is now only used for debug purpose, but later, it will be used as a
common interfaces. So, move the sbuf related code out of the debug directory.
Tracked-On: #8209
Signed-off-by: Conghui <conghui.chen@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
