Pull AFS fixes from David Howells:
- Fix a tracepoint that causes one of the tracing subsystem query files
to crash if the module is loaded
- Fix afs_writepages() to take account of whether the storage rpc
actually succeeded when updating the cyclic writeback counter
- Fix some error code propagation/handling
- Fix place where afs_writepages() was setting writeback_index to a
file position rather than a page index
* tag 'afs-fixes-
20210721' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
afs: Remove redundant assignment to ret
afs: Fix setting of writeback_index
afs: check function return
afs: Fix tracepoint string placement with built-in AFS