-
Notifications
You must be signed in to change notification settings - Fork 0
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
VMCI: dma dg: add support for DMA datagrams receive
Use the DMA based receive operation instead of the ioread8_rep based datagram receive when DMA datagrams are supported. In the receive operation, configure the header to point to the page aligned VMCI_MAX_DG_SIZE part of the receive buffer using s/g configuration for the header. This ensures that the existing dispatch routine can be used with little modification. Initiate the receive by writing the lower 32 bit of the buffer to the VMCI_DATA_IN_LOW_ADDR register, and wait for the busy flag to be changed by the device using a wait queue. The existing dispatch routine for received datagrams is reused for the DMA datagrams with a few modifications: - the receive buffer is always the maximum size for DMA datagrams (IO ports would try with a shorter buffer first to reduce overhead of the ioread8_rep operation). - for DMA datagrams, datagrams are provided contiguous in the buffer as opposed to IO port datagrams, where they can start on any page boundary Reviewed-by: Vishnu Dasa <vdasa@vmware.com> Signed-off-by: Jorgen Hansen <jhansen@vmware.com> Link: https://lore.kernel.org/r/20220207102725.2742-9-jhansen@vmware.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
- Loading branch information
Jorgen Hansen
authored and
Greg Kroah-Hartman
committed
Feb 8, 2022
1 parent
22aa5c7
commit 463713e
Showing
1 changed file
with
79 additions
and
24 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters