a7e1ac7bdc
Ensure a metadata and system block group can be activated on write time, by leaving a certain number of active zones when trying to activate a data block group. Zones for two metadata block groups (normal and tree-log) and one system block group are reserved, according to the profile type: two zones per block group on the DUP profile and one zone per block group otherwise. The reservation must be freed once a non-data block group is allocated. If not, we over-reserve the active zones and data block group activation will suffer. For the dynamic reservation count, we need to manage the reservation count per device. The reservation count variable is protected by fs_info->zone_active_bgs_lock. Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
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.