hfsplus: get rid of write_super

This patch makes hfsplus stop using the VFS '->write_super()' method along with
the 's_dirt' superblock flag, because they are on their way out.

The whole "superblock write-out" VFS infrastructure is served by the
'sync_supers()' kernel thread, which wakes up every 5 (by default) seconds and
writes out all dirty superblocks using the '->write_super()' call-back.  But the
problem with this thread is that it wastes power by waking up the system every
5 seconds, even if there are no diry superblocks, or there are no client
file-systems which would need this (e.g., btrfs does not use
'->write_super()'). So we want to kill it completely and thus, we need to make
file-systems to stop using the '->write_super()' VFS service, and then remove
it together with the kernel thread.

Tested using fsstress from the LTP project.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 2 insertions, 2 deletions

diff --git a/fs/hfsplus/bitmap.c b/fs/hfsplus/bitmap.c
index 1cad80c789c..4cfbe2edd29 100644
--- a/fs/hfsplus/bitmap.c
+++ b/fs/hfsplus/bitmap.c
@@ -153,7 +153,7 @@ done:
         kunmap(page);
         *max = offset + (curr - pptr) * 32 + i - start;
         sbi->free_blocks -= *max;
-        sb->s_dirt = 1;
+        hfsplus_mark_mdb_dirty(sb);
         dprint(DBG_BITMAP, "-> %u,%u\n", start, *max);
 out:
         mutex_unlock(&sbi->alloc_mutex);
@@ -228,7 +228,7 @@ out:
         set_page_dirty(page);
         kunmap(page);
         sbi->free_blocks += len;
-        sb->s_dirt = 1;
+        hfsplus_mark_mdb_dirty(sb);
         mutex_unlock(&sbi->alloc_mutex);
 
         return 0;