Commit 6d4338cb authored by Logan Gunthorpe's avatar Logan Gunthorpe Committed by Jens Axboe
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ABI: sysfs-bus-pci: add documentation for p2pmem allocate 



Add documentation for the p2pmem/allocate binary file which allows
for allocating p2pmem buffers in userspace for passing to drivers
that support them. (Currently only O_DIRECT to NVMe devices.)

Signed-off-by: default avatarLogan Gunthorpe <logang@deltatee.com>
Reviewed-by: default avatarJohn Hubbard <jhubbard@nvidia.com>
Reviewed-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: default avatarChaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221021174116.7200-10-logang@deltatee.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 7e9c7ef8

Documentation/ABI/testing/sysfs-bus-pci

+10 −0
Original line number Diff line number Diff line
@@ -407,6 +407,16 @@ Description: 
	        file contains a '1' if the memory has been published for

		use outside the driver that owns the device.



What:		/sys/bus/pci/devices/.../p2pmem/allocate

Date:		August 2022

Contact:	Logan Gunthorpe <logang@deltatee.com>

Description:

		This file allows mapping p2pmem into userspace. For each

		mmap() call on this file, the kernel will allocate a chunk

		of Peer-to-Peer memory for use in Peer-to-Peer transactions.

		This memory can be used in O_DIRECT calls to NVMe backed

		files for Peer-to-Peer copies.



What:		/sys/bus/pci/devices/.../link/clkpm

		/sys/bus/pci/devices/.../link/l0s_aspm

		/sys/bus/pci/devices/.../link/l1_aspm