Merge tag 'for-linus-5.13-ofs-1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux

Pull orangefs updates from Mike Marshall:
 "orangefs: implement orangefs_readahead

  mm/readahead.c/read_pages was quite a bit different back when I put my
  open-coded readahead logic into orangefs_readpage. That logic seemed
  to work as designed back then, it is a trainwreck now.

  This implements orangefs_readahead using the new xarray and
  readahead_expand features and removes all my open-coded readahead
  logic.

  This results in an extreme read performance improvement, these sample
  numbers are from my test VM:

  Here's an example of what's upstream in
  5.11.8-200.fc33.x86_64:

     30+0 records in
     30+0 records out
     125829120 bytes (126 MB, 120 MiB) copied, 5.77943 s, 21.8 MB/s

  And here's this version of orangefs_readahead on top of 5.12.0-rc4:

     30+0 records in
     30+0 records out
     125829120 bytes (126 MB, 120 MiB) copied, 0.325919 s, 386 MB/s

  There are four xfstest regressions with this patch. David Howells and
  Matthew Wilcox have been helping me work with this code"

* tag 'for-linus-5.13-ofs-1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux:
  orangefs: leave files in the page cache for a few micro seconds at least
  Orangef: implement orangefs_readahead.