readahead: convert ext3/ext4 invocations
authorFengguang Wu <wfg@mail.ustc.edu.cn>
Thu, 19 Jul 2007 08:48:04 +0000 (01:48 -0700)
committerLinus Torvalds <torvalds@woody.linux-foundation.org>
Thu, 19 Jul 2007 17:04:44 +0000 (10:04 -0700)
commitdc7868fcb9a73990e6f30371c1be465c436a7a7f
tree21dfd3e625bb4a9f78a7795f0a5b110c3dd8843e
parenta08a166fe77d9f9ad88ed6d06b97e73453661f89
readahead: convert ext3/ext4 invocations

Convert ext3/ext4 dir reads to use on-demand readahead.

Readahead for dirs operates _not_ on file level, but on blockdev level.  This
makes a difference when the data blocks are not continuous.  And the read
routine is somehow opaque: there's no handy info about the status of current
page.  So a simplified call scheme is employed: to call into readahead
whenever the current page falls out of readahead windows.

Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Cc: Steven Pratt <slpratt@austin.ibm.com>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/ext3/dir.c
fs/ext4/dir.c