From: David S. Miller Date: Fri, 27 Mar 2020 02:39:27 +0000 (-0700) Subject: Merge branch 'implement-DEVLINK_CMD_REGION_NEW' X-Git-Tag: baikal/aarch64/sdk6.1~9689^2~66 X-Git-Url: https://git.baikalelectronics.ru/sdk/?a=commitdiff_plain;h=491289a77962ea1c7fbcbf823c74024102134607;p=kernel.git Merge branch 'implement-DEVLINK_CMD_REGION_NEW' Jacob Keller says: ==================== implement DEVLINK_CMD_REGION_NEW This series adds support for the DEVLINK_CMD_REGION_NEW operation, used to enable userspace requesting a snapshot of a region on demand. This can be useful to enable adding regions for a driver for which there is no trigger to create snapshots. By making this a core part of devlink, there is no need for the drivers to use a separate channel such as debugfs. The primary intent for this kind of region is to expose device information that might be useful for diagnostics and information gathering. The first few patches refactor regions to support a new ops structure for extending the available operations that regions can perform. This includes converting the destructor into an op from a function argument. Next, patches refactor the snapshot id allocation to use an xarray which tracks the number of current snapshots using a given id. This is done so that id lifetime can be determined, and ids can be released when no longer in use. Without this change, snapshot ids remain used forever, until the snapshot_id count rolled over UINT_MAX. Finally, code to enable the previously unused DEVLINK_CMD_REGION_NEW is added. This code enforces that the snapshot id is always provided, unlike previous revisions of this series. Finally, a patch is added to enable using this new command via the .snapshot callback in both netdevsim and the ice driver. For the ice driver, a new "nvm-flash" region is added, which will enable read access to the NVM flash contents. The intention for this is to allow diagnostics tools to gather information about the device. By using a snapshot and gathering the NVM contents all at once, the contents can be atomic. Links to previous discussions: 1st RFC - https://lore.kernel.org/netdev/20200130225913.1671982-1-jacob.e.keller@intel.com/ 2nd RFC - https://lore.kernel.org/netdev/20200214232223.3442651-1-jacob.e.keller@intel.com/ v1 - https://lore.kernel.org/netdev/20200324223445.2077900-1-jacob.e.keller@intel.com/ v2 - https://lore.kernel.org/netdev/20200326035157.2211090-1-jacob.e.keller@intel.com/ Major changes since RFC: * use an xarray for tracking snapshot ids, rather than an IDR * remove support for auto-generated snapshot ids in DEVLINK_CMD_REGION_NEW See each patch for an individual changelog per-patch ==================== Signed-off-by: David S. Miller --- 491289a77962ea1c7fbcbf823c74024102134607