diff options
| author | David Howells <dhowells@redhat.com> | 2023-10-12 09:06:24 +0100 |
|---|---|---|
| committer | David Howells <dhowells@redhat.com> | 2023-12-28 09:45:27 +0000 |
| commit | 41d8e7673a7726cba57cb8112d81c89cfb6c3e35 (patch) | |
| tree | 1ae96a5d0a483df02adc4f4f1af6c209b3fbc25d /fs/netfs/internal.h | |
| parent | 4a79616cfb27d76947ea37f0336745ef929d56be (diff) | |
netfs: Implement a write-through caching option
Provide a flag whereby a filesystem may request that cifs_perform_write()
perform write-through caching. This involves putting pages directly into
writeback rather than dirty and attaching them to a write operation as we
go.
Further, the writes being made are limited to the byte range being written
rather than whole folios being written. This can be used by cifs, for
example, to deal with strict byte-range locking.
This can't be used with content encryption as that may require expansion of
the write RPC beyond the write being made.
This doesn't affect writes via mmap - those are written back in the normal
way; similarly failed writethrough writes are marked dirty and left to
writeback to retry. Another option would be to simply invalidate them, but
the contents can be simultaneously accessed by read() and through mmap.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org
Diffstat (limited to 'fs/netfs/internal.h')
| -rw-r--r-- | fs/netfs/internal.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/fs/netfs/internal.h b/fs/netfs/internal.h index 2de4f826dbe4..d2d63120ac60 100644 --- a/fs/netfs/internal.h +++ b/fs/netfs/internal.h @@ -101,6 +101,9 @@ static inline void netfs_see_request(struct netfs_io_request *rreq, */ int netfs_begin_write(struct netfs_io_request *wreq, bool may_wait, enum netfs_write_trace what); +struct netfs_io_request *netfs_begin_writethrough(struct kiocb *iocb, size_t len); +int netfs_advance_writethrough(struct netfs_io_request *wreq, size_t copied, bool to_page_end); +int netfs_end_writethrough(struct netfs_io_request *wreq, struct kiocb *iocb); /* * stats.c |