cababeac91
[ Upstream commit 20d0a107fb35f37578b919f62bd474d6d358d579 ]
Reading past end of file returns EOF for aligned reads but -EINVAL for
unaligned reads on f2fs. While documentation is not strict about this
corner case, most filesystem returns EOF on this case, like iomap
filesystems. This patch consolidates the behavior for f2fs, by making
it return EOF(0).
it can be verified by a read loop on a file that does a partial read
before EOF (A file that doesn't end at an aligned address). The
following code fails on an unaligned file on f2fs, but not on
btrfs, ext4, and xfs.
while (done < total) {
ssize_t delta = pread(fd, buf + done, total - done, off + done);
if (!delta)
break;
...
}
It is arguable whether filesystems should actually return EOF or
-EINVAL, but since iomap filesystems support it, and so does the
original DIO code, it seems reasonable to consolidate on that.
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.