GFS2: Use ->dirty_inode()
The aim of this patch is to use the newly enhanced ->dirty_inode()
super block operation to deal with atime updates, rather than
piggy backing that code into ->write_inode() as is currently
done.
The net result is a simplification of the code in various places
and a reduction of the number of gfs2_dinode_out() calls since
this is now implied by ->dirty_inode().
Some of the mark_inode_dirty() calls have been moved under glocks
in order to take advantage of then being able to avoid locking in
->dirty_inode() when we already have suitable locks.
One consequence is that generic_write_end() now correctly deals
with file size updates, so that we do not need a separate check
for that afterwards. This also, indirectly, means that fdatasync
should work correctly on GFS2 - the current code always syncs the
metadata whether it needs to or not.
Has survived testing with postmark (with and without atime) and
also fsx.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c
index 9961de7..b05fa59 100644
--- a/fs/gfs2/super.c
+++ b/fs/gfs2/super.c
@@ -752,47 +752,15 @@
struct gfs2_sbd *sdp = GFS2_SB(inode);
struct address_space *metamapping = gfs2_glock2aspace(ip->i_gl);
struct backing_dev_info *bdi = metamapping->backing_dev_info;
- struct gfs2_holder gh;
- struct buffer_head *bh;
- struct timespec atime;
- struct gfs2_dinode *di;
- int ret = -EAGAIN;
- int unlock_required = 0;
+ int ret = 0;
- /* Skip timestamp update, if this is from a memalloc */
- if (current->flags & PF_MEMALLOC)
- goto do_flush;
- if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
- ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
- if (ret)
- goto do_flush;
- unlock_required = 1;
- }
- ret = gfs2_meta_inode_buffer(ip, &bh);
- if (ret == 0) {
- di = (struct gfs2_dinode *)bh->b_data;
- atime.tv_sec = be64_to_cpu(di->di_atime);
- atime.tv_nsec = be32_to_cpu(di->di_atime_nsec);
- if (timespec_compare(&inode->i_atime, &atime) > 0) {
- ret = gfs2_trans_begin(sdp, RES_DINODE, 0);
- if (ret == 0) {
- gfs2_trans_add_bh(ip->i_gl, bh, 1);
- gfs2_dinode_out(ip, bh->b_data);
- gfs2_trans_end(sdp);
- }
- }
- brelse(bh);
- }
- if (unlock_required)
- gfs2_glock_dq_uninit(&gh);
-do_flush:
if (wbc->sync_mode == WB_SYNC_ALL)
gfs2_log_flush(GFS2_SB(inode), ip->i_gl);
if (bdi->dirty_exceeded)
gfs2_ail1_flush(sdp, wbc);
else
filemap_fdatawrite(metamapping);
- if (!ret && (wbc->sync_mode == WB_SYNC_ALL))
+ if (wbc->sync_mode == WB_SYNC_ALL)
ret = filemap_fdatawait(metamapping);
if (ret)
mark_inode_dirty_sync(inode);
@@ -800,6 +768,64 @@
}
/**
+ * gfs2_dirty_inode - check for atime updates
+ * @inode: The inode in question
+ * @flags: The type of dirty
+ *
+ * Unfortunately it can be called under any combination of inode
+ * glock and transaction lock, so we have to check carefully.
+ *
+ * At the moment this deals only with atime - it should be possible
+ * to expand that role in future, once a review of the locking has
+ * been carried out.
+ */
+
+static void gfs2_dirty_inode(struct inode *inode, int flags)
+{
+ struct gfs2_inode *ip = GFS2_I(inode);
+ struct gfs2_sbd *sdp = GFS2_SB(inode);
+ struct buffer_head *bh;
+ struct gfs2_holder gh;
+ int need_unlock = 0;
+ int need_endtrans = 0;
+ int ret;
+
+ if (!(flags & (I_DIRTY_DATASYNC|I_DIRTY_SYNC)))
+ return;
+
+ if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
+ ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
+ if (ret) {
+ fs_err(sdp, "dirty_inode: glock %d\n", ret);
+ return;
+ }
+ need_unlock = 1;
+ }
+
+ if (current->journal_info == NULL) {
+ ret = gfs2_trans_begin(sdp, RES_DINODE, 0);
+ if (ret) {
+ fs_err(sdp, "dirty_inode: gfs2_trans_begin %d\n", ret);
+ goto out;
+ }
+ need_endtrans = 1;
+ }
+
+ ret = gfs2_meta_inode_buffer(ip, &bh);
+ if (ret == 0) {
+ gfs2_trans_add_bh(ip->i_gl, bh, 1);
+ gfs2_dinode_out(ip, bh->b_data);
+ brelse(bh);
+ }
+
+ if (need_endtrans)
+ gfs2_trans_end(sdp);
+out:
+ if (need_unlock)
+ gfs2_glock_dq_uninit(&gh);
+}
+
+/**
* gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
* @sdp: the filesystem
*
@@ -1578,6 +1604,7 @@
.alloc_inode = gfs2_alloc_inode,
.destroy_inode = gfs2_destroy_inode,
.write_inode = gfs2_write_inode,
+ .dirty_inode = gfs2_dirty_inode,
.evict_inode = gfs2_evict_inode,
.put_super = gfs2_put_super,
.sync_fs = gfs2_sync_fs,