This patch adds to e2fsck the ability to pre-fetch metadata into the
page cache in the hopes of speeding up fsck runs. There are two new
functions -- the first allows a caller to readahead a list of blocks,
and the second is a helper function that uses that first mechanism to
load group data (bitmaps, inode tables).
These new e2fsck routines require the addition of a dblist API to
allow us to iterate a subset of a dblist. This will enable
incremental directory block readahead in e2fsck pass 2.
There's also a function to estimate the readahead given a FS.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
