2133460061
At btrfs_add_extent_mapping(), if we failed to merge the extent map, which is unexpected and theoretically should never happen, we use WARN_ONCE() to log a message which is not great because we don't get information about which filesystem it relates to in case we have multiple btrfs filesystems mounted. So change this to use btrfs_warn() and surround the error check with WARN_ON() so we always get a useful stack trace and the condition is flagged as "unlikely" since it's not expected to ever happen. Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.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.