GFS2: Extend the life of the reservations

This patch lengthens the lifespan of the reservations structure for
inodes. Before, they were allocated and deallocated for every write
operation. With this patch, they are allocated when the first write
occurs, and deallocated when the last process closes the file.
It's more efficient to do it this way because it saves GFS2 a lot of
unnecessary allocates and frees. It also gives us more flexibility
for the future: (1) we can now fold the qadata structure back into
the structure and save those alloc/frees, (2) we can use this for
multi-block reservations.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

1 files changed, 11 insertions, 2 deletions

diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c
index b97178e..197cc2d 100644
--- a/fs/gfs2/quota.c
+++ b/fs/gfs2/quota.c
@@ -764,6 +764,10 @@ static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
 	unsigned int nalloc = 0, blocks;
 	int error;
 
+	error = gfs2_rs_alloc(ip);
+	if (error)
+		return error;
+
 	gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
 			      &data_blocks, &ind_blocks);
 
@@ -1549,10 +1553,14 @@ static int gfs2_set_dqblk(struct super_block *sb, int type, qid_t id,
 	if (error)
 		return error;
 
+	error = gfs2_rs_alloc(ip);
+	if (error)
+		goto out_put;
+
 	mutex_lock(&ip->i_inode.i_mutex);
 	error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE, 0, &q_gh);
 	if (error)
-		goto out_put;
+		goto out_unlockput;
 	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
 	if (error)
 		goto out_q;
@@ -1609,8 +1617,9 @@ out_i:
 	gfs2_glock_dq_uninit(&i_gh);
 out_q:
 	gfs2_glock_dq_uninit(&q_gh);
-out_put:
+out_unlockput:
 	mutex_unlock(&ip->i_inode.i_mutex);
+out_put:
 	qd_put(qd);
 	return error;
 }