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> --- Documentation/ABI/testing/sysfs-bus-pci | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci index 6fc2c2efe8ab..dca5e032b4fa 100644 --- a/Documentation/ABI/testing/sysfs-bus-pci +++ b/Documentation/ABI/testing/sysfs-bus-pci @@ -171,7 +171,7 @@ Description: binary file containing the Vital Product Data for the device. It should follow the VPD format defined in PCI Specification 2.1 or 2.2, but users should consider - that some devices may have incorrectly formatted data. + that some devices may have incorrectly formatted data. If the underlying VPD has a writable section then the corresponding section of this file will be writable. @@ -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: + Thes attribute 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
