Hi,
在 2023/11/28 0:32, Christoph Hellwig 写道:
On Mon, Nov 27, 2023 at 09:07:22PM +0800, Yu Kuai wrote:
1) Is't okay to add a new helper to pass in bdev for following apis?
For some we already have them (e.g. bdev_nr_bytes to read the bdev)
size, for some we need to add them. The big thing that seems to
stick out is page cache API, and I think that is where we need to
define maintainable APIs for file systems and others to use the
block device page cache. Probably only in folio versions and not
pages once if we're touching the code anyay
Thanks for the advice! In case I'm understanding correctly, do you mean
that all other fs/drivers that is using pages versions can safely switch
to folio versions now?
By the way, my orginal idea was trying to add a new field 'bd_flags'
in block_devcie, and then add a new bit so that bio_check_ro() will
only warn once for each partition. Now that this patchset will be quite
complex, I'll add a new bool field 'bd_ro_warned' to fix the above
problem first, and then add 'bd_flags' once this patchset is done.
Thanks,
Kuai
2) For the file fs/buffer.c, there are some special usage like
following that I don't think it's good to add a helper:
spin_lock(&bd_inode->i_mapping->private_lock);
Is't okay to move following apis from fs/buffer.c directly to
block/bdev.c?
__find_get_block
bdev_getblk
I'm not sure moving is a good idea, but we might end up the
some kind of low-level access from buffer.c, be that special
helpers, a separate header or something else. Let's sort out
the rest of the kernel first.
.
