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: Logan Gunthorpe <logang@xxxxxxxxxxxx> Reviewed-by: John Hubbard <jhubbard@xxxxxxxxxx> Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- Documentation/ABI/testing/sysfs-bus-pci | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci index 840727fc75dc..ecf47559f495 100644 --- a/Documentation/ABI/testing/sysfs-bus-pci +++ b/Documentation/ABI/testing/sysfs-bus-pci @@ -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@xxxxxxxxxxxx> +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 -- 2.30.2
