tree d3708c9b2f6e3023a7da4452d90f65e99a007213
parent 0e378df15cd87f540f1ba9503e4aa039e1c72741
author Alex Gartrell <agartrell@fb.com> 1400616476 -0700
committer Chris Mason <clm@fb.com> 1402359657 -0700

btrfs: Drop EXTENT_UPTODATE check in hole punching and direct locking

In these instances, we are trying to determine if a page has been accessed
since we began the operation for the sake of retry.  This is easily
accomplished by doing a gang lookup in the page mapping radix tree, and it
saves us the dependency on the flag (so that we might eventually delete
it).

btrfs_page_exists_in_range borrows heavily from find_get_page, replacing
the radix tree look up with a gang lookup of 1, so that we can find the
next highest page >= index and see if it falls into our lock range.

Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Alex Gartrell <agartrell@fb.com>