e959d3c1df
In function btrfs_read_sys_array(), we allocate a real extent buffer using btrfs_find_create_tree_block(). Such extent buffer will be even cached into buffer_radix tree, and using btree inode address space. However we only use such extent buffer to enable the accessors, thus we don't even need to bother using real extent buffer, a dummy one is what we really need. And for dummy extent buffer, we no longer need to do any special handling for the first page, as subpage helper is already doing it properly. Signed-off-by: Qu Wenruo <wqu@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.