tree 2d2db84b18244673371c5478fbb365560cdb071a
parent 4c24dab391003b99b1e0784fd41fe756cb07039e
author Stephen Warren <swarren@nvidia.com> 1548878285 -0700
committer Tom Rini <trini@konsulko.com> 1554838455 -0400

fs: ext4: cache extent data

When a file contains extents, U-Boot currently reads extent-related data
for each block in the file, even if that data is located in the same
block each time. This significantly slows down loading of files that use
extents. Implement a very dumb cache to prevent repeatedly reading the
same block. Files with extents now load as fast as files without.

Note: There are many cases where read_allocated_block() is called. This
patch only addresses one of those places; all others still read redundant
data in any case they did before. This is a minimal patch to fix the
load command; other cases aren't fixed.

Signed-off-by: Stephen Warren <swarren@nvidia.com>