Commit graph

5 commits

Author SHA1 Message Date
Ben Gras
bd3cde4571 Move primary cache code to libminixfs.
Add primary cache management feature to libminixfs as mfs and ext2
currently do separately, remove cache code from mfs and ext2, and make
them use the libminixfs interface. This makes all fields of the buf
struct private to libminixfs and FS clients aren't supposed to access
them at all. Only the opaque 'void *data' field (the FS block contents,
used to be called bp) is to be accessed by the FS client.

The main purpose is to implement the interface to the 2ndary vm cache
just once, get rid of some code duplication, and add a little
abstraction to reduce the code inertia of the whole caching business.

Some minor sanity checking and prohibition done by mfs in this code
as removed from the generic primary cache code as a result:
        - checking all inodes are not in use when allocating/resizing
          the cache
        - checking readonly filesystems aren't written to
        - checking the superblock isn't written to on mounted filesystems

The minixfslib code relies on fs_blockstats() in the client filesystem to
return some FS usage information.
2012-10-23 19:48:38 +02:00
David van Moolenbroek
0c11190cdc MFS: reimplement block clean marking fix
MFS' get_block() must never return a newly acquired block buffer that
is marked dirty from previous use. This patch replaces git-dd59d50,
which assumed a working model where blocks for device NO_DEV would
never be dirty. For at least one scenario, that assumption does not
hold, triggering superblock overwrite warnings. In this patch, blocks
are explicitly marked as clean upon being repurposed. The working
model is now restored to be: the dirty state of a block is relevant
only when its associated device is not set to NO_DEV.
2012-04-20 17:40:47 +02:00
Ben Gras
dd59d50944 mfs: mark blocks clean when invalidated
. it could happen that newly filled blocks were still marked
	  dirty
	. causing unnecessary i/o and the new warning of the superblock
	  being written
2012-01-18 17:51:04 +01:00
Ben Gras
9a664b4984 mfs: restore readonly mounting
. use dirty marking hooks to check and warn
	  when inodes/bufs are marked dirty on a readonly
	  mounted fs
	. add readonly mount checks to restore readonly
	  mounting

Signed-off-by: Ben Gras <ben@minix3.org>
2011-12-22 01:29:27 +01:00
Ben Gras
9b7d357ca1 mfs: use macros to mark blocks and inodes dirty
. No functional change
	. Only serves to get hooks to do checks in
	. e.g. should things be marked dirty when we are
	  mounted readonly

Signed-off-by: Ben Gras <ben@minix3.org>
2011-12-22 01:29:27 +01:00