dc4d137ee3
Add support for user space to set a max open zone and a max active zone limit via configfs. By default, the default values are 0 == no limit. Call the block layer API functions used for exposing the configured limits to sysfs. Add accounting in null_blk_zoned so that these new limits are respected. Performing an operation that would exceed these limits results in a standard I/O error. A max open zone limit exists in the ZBC standard. While null_blk_zoned is used to test the Zoned Block Device model in Linux, when it comes to differences between ZBC and ZNS, null_blk_zoned mostly follows ZBC. Therefore, implement the manage open zone resources function from ZBC, but additionally add support for max active zones. This enables user space not only to test against a device with an open zone limit, but also to test against a device with an active zone limit. Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.