eb3570607c
The new member is an array of sector_ptr pointers, they will represent
all sectors inside a full stripe (including P/Q).
They co-operate with btrfs_raid_bio::stripe_pages:
stripe_pages: | Page 0, range [0, 64K) | Page 1 ...
stripe_sectors: | | | ... | |
| | \- sector 15, page 0, pgoff=60K
| \- sector 1, page 0, pgoff=4K
\---- sector 0, page 0, pfoff=0
With such structure, we can represent subpage sectors without using
extra pages.
Here we introduce a new helper, index_stripe_sectors(), to update
stripe_sectors[] to point to correct page and pgoff.
So every time rbio::stripe_pages[] pointer gets updated, the new helper
should be called.
The following functions have to call the new helper:
- steal_rbio()
- alloc_rbio_pages()
- alloc_rbio_parity_pages()
- alloc_rbio_essential_pages()
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.