fa485d21a7
Btrfs on-disk format chose to use u64 for almost everything, but there are a other restrictions that won't let us use more than u32 for things like extent length (the maximum length is 128MiB for non-hole extents), or stripe length (we have device number limit). This means if we don't have extra handling to convert u64 to u32, we will always have some questionable operations like "u32 = u64 >> sectorsize_bits" in the code. This patch will try to address the problem by reducing the width for the following members/parameters: - scrub_parity::stripe_len - @len of scrub_pages() - @extent_len of scrub_remap_extent() - @len of scrub_parity_mark_sectors_error() - @len of scrub_parity_mark_sectors_data() - @len of scrub_extent() - @len of scrub_pages_for_parity() - @len of scrub_extent_for_parity() For members extracted from on-disk structure, like map->stripe_len, they will be kept as is. Since that modification would require on-disk format change. There will be cases like "u32 = u64 - u64" or "u32 = u64", for such call sites, extra ASSERT() is added to be extra safe for debug builds. 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.