33a5f1709a
When doing a synchronous write on an encrypted inode, we have no guarantee that the caller is writing crypto block-aligned data. When that happens, we must do a read/modify/write cycle. First, expand the range to cover complete blocks. If we had to change the original pos or length, issue a read to fill the first and/or last pages, and fetch the version of the object from the result. We then copy data into the pages as usual, encrypt the result and issue a write prefixed by an assertion that the version hasn't changed. If it has changed then we restart the whole thing again. If there is no object at that position in the file (-ENOENT), we prefix the write on an exclusive create of the object instead. Signed-off-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Xiubo Li <xiubli@redhat.com> Reviewed-and-tested-by: Luís Henriques <lhenriques@suse.de> Reviewed-by: Milind Changire <mchangir@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.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.