Merge tag 'afs-netfs-lib-20210426' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull AFS updates from David Howells:
"Use the new netfs lib.
Begin the process of overhauling the use of the fscache API by AFS and
the introduction of support for features such as Transparent Huge
Pages (THPs).
- Add some support for THPs, including using core VM helper functions
to find details of pages.
- Use the ITER_XARRAY I/O iterator to mediate access to the pagecache
as this handles THPs and doesn't require allocation of large bvec
arrays.
- Delegate address_space read/pre-write I/O methods for AFS to the
netfs helper library. A method is provided to the library that
allows it to issue a read against the server.
This includes a change in use for PG_fscache (it now indicates a
DIO write in progress from the marked page), so a number of waits
need to be deployed for it.
- Split the core AFS writeback function to make it easier to modify
in future patches to handle writing to the cache. [This might
feasibly make more sense moved out into my fscache-iter branch].
I've tested these with "xfstests -g quick" against an AFS volume
(xfstests needs patching to make it work). With this, AFS without a
cache passes all expected xfstests; with a cache, there's an extra
failure, but that's also there before these patches. Fixing that
probably requires a greater overhaul (as can be found on my
fscache-iter branch, but that's for a later time).
Thanks should go to Marc Dionne and Jeff Altman of AuriStor for
exercising the patches in their test farm also"
Link: https://lore.kernel.org/lkml/3785063.1619482429@warthog.procyon.org.uk/
* tag 'afs-netfs-lib-20210426' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
afs: Use the netfs_write_begin() helper
afs: Use new netfs lib read helper API
afs: Use the fs operation ops to handle FetchData completion
afs: Prepare for use of THPs
afs: Extract writeback extension into its own function
afs: Wait on PG_fscache before modifying/releasing a page
afs: Use ITER_XARRAY for writing
afs: Set up the iov_iter before calling afs_extract_data()
afs: Log remote unmarshalling errors
afs: Don't truncate iter during data fetch
afs: Move key to afs_read struct
afs: Print the operation debug_id when logging an unexpected data version
afs: Pass page into dirty region helpers to provide THP size
afs: Disable use of the fscache I/O routines
