GFS2: Extract quota data from reservations structure (revert 5407e24)

This patch basically reverts the majority of patch 5407e24.
That patch eliminated the gfs2_qadata structure in favor of just
using the reservations structure. The problem with doing that is that
it increases the size of the reservations structure. That is not an
issue until it comes time to fold the reservations structure into the
inode in memory so we know it's always there. By separating out the
quota structure again, we aren't punishing the non-quota users by
making all the inodes bigger, requiring more slab space. This patch
creates a new slab area to allocate the quota stuff so it's managed
a little more sanely.

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

1 files changed, 70 insertions, 35 deletions

diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c
index e01298d922c09..b845efdb5e3a4 100644
--- a/fs/gfs2/quota.c
+++ b/fs/gfs2/quota.c
@@ -527,37 +527,70 @@ static void qdsb_put(struct gfs2_quota_data *qd)
 	qd_put(qd);
 }
 
+/**
+ * gfs2_qa_alloc - make sure we have a quota allocations data structure,
+ *                 if necessary
+ * @ip: the inode for this reservation
+ */
+int gfs2_qa_alloc(struct gfs2_inode *ip)
+{
+	int error = 0;
+	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
+
+	if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
+		return 0;
+
+	down_write(&ip->i_rw_mutex);
+	if (ip->i_qadata == NULL) {
+		ip->i_qadata = kmem_cache_zalloc(gfs2_qadata_cachep, GFP_NOFS);
+		if (!ip->i_qadata)
+			error = -ENOMEM;
+	}
+	up_write(&ip->i_rw_mutex);
+	return error;
+}
+
+void gfs2_qa_delete(struct gfs2_inode *ip)
+{
+	down_write(&ip->i_rw_mutex);
+	if (ip->i_qadata) {
+		kmem_cache_free(gfs2_qadata_cachep, ip->i_qadata);
+		ip->i_qadata = NULL;
+	}
+	up_write(&ip->i_rw_mutex);
+}
+
 int gfs2_quota_hold(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
 {
 	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 	struct gfs2_quota_data **qd;
 	int error;
 
-	if (ip->i_res == NULL) {
-		error = gfs2_rs_alloc(ip);
+	if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
+		return 0;
+
+	if (ip->i_qadata == NULL) {
+		error = gfs2_rsqa_alloc(ip);
 		if (error)
 			return error;
 	}
 
-	qd = ip->i_res->rs_qa_qd;
+	qd = ip->i_qadata->qa_qd;
 
-	if (gfs2_assert_warn(sdp, !ip->i_res->rs_qa_qd_num) ||
+	if (gfs2_assert_warn(sdp, !ip->i_qadata->qa_qd_num) ||
 	    gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags)))
 		return -EIO;
 
-	if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
-		return 0;
-
 	error = qdsb_get(sdp, make_kqid_uid(ip->i_inode.i_uid), qd);
 	if (error)
 		goto out;
-	ip->i_res->rs_qa_qd_num++;
+	ip->i_qadata->qa_qd_num++;
 	qd++;
 
 	error = qdsb_get(sdp, make_kqid_gid(ip->i_inode.i_gid), qd);
 	if (error)
 		goto out;
-	ip->i_res->rs_qa_qd_num++;
+	ip->i_qadata->qa_qd_num++;
 	qd++;
 
 	if (!uid_eq(uid, NO_UID_QUOTA_CHANGE) &&
@@ -565,7 +598,7 @@ int gfs2_quota_hold(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
 		error = qdsb_get(sdp, make_kqid_uid(uid), qd);
 		if (error)
 			goto out;
-		ip->i_res->rs_qa_qd_num++;
+		ip->i_qadata->qa_qd_num++;
 		qd++;
 	}
 
@@ -574,7 +607,7 @@ int gfs2_quota_hold(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
 		error = qdsb_get(sdp, make_kqid_gid(gid), qd);
 		if (error)
 			goto out;
-		ip->i_res->rs_qa_qd_num++;
+		ip->i_qadata->qa_qd_num++;
 		qd++;
 	}
 
@@ -589,15 +622,15 @@ void gfs2_quota_unhold(struct gfs2_inode *ip)
 	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 	unsigned int x;
 
-	if (ip->i_res == NULL)
+	if (ip->i_qadata == NULL)
 		return;
 	gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
 
-	for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
-		qdsb_put(ip->i_res->rs_qa_qd[x]);
-		ip->i_res->rs_qa_qd[x] = NULL;
+	for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
+		qdsb_put(ip->i_qadata->qa_qd[x]);
+		ip->i_qadata->qa_qd[x] = NULL;
 	}
-	ip->i_res->rs_qa_qd_num = 0;
+	ip->i_qadata->qa_qd_num = 0;
 }
 
 static int sort_qd(const void *a, const void *b)
@@ -843,7 +876,7 @@ 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);
+	error = gfs2_rsqa_alloc(ip);
 	if (error)
 		return error;
 
@@ -1006,20 +1039,20 @@ int gfs2_quota_lock(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
 	unsigned int x;
 	int error = 0;
 
-	error = gfs2_quota_hold(ip, uid, gid);
-	if (error)
-		return error;
-
 	if (capable(CAP_SYS_RESOURCE) ||
 	    sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
 		return 0;
 
-	sort(ip->i_res->rs_qa_qd, ip->i_res->rs_qa_qd_num,
+	error = gfs2_quota_hold(ip, uid, gid);
+	if (error)
+		return error;
+
+	sort(ip->i_qadata->qa_qd, ip->i_qadata->qa_qd_num,
 	     sizeof(struct gfs2_quota_data *), sort_qd, NULL);
 
-	for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
-		qd = ip->i_res->rs_qa_qd[x];
-		error = do_glock(qd, NO_FORCE, &ip->i_res->rs_qa_qd_ghs[x]);
+	for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
+		qd = ip->i_qadata->qa_qd[x];
+		error = do_glock(qd, NO_FORCE, &ip->i_qadata->qa_qd_ghs[x]);
 		if (error)
 			break;
 	}
@@ -1028,7 +1061,7 @@ int gfs2_quota_lock(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
 		set_bit(GIF_QD_LOCKED, &ip->i_flags);
 	else {
 		while (x--)
-			gfs2_glock_dq_uninit(&ip->i_res->rs_qa_qd_ghs[x]);
+			gfs2_glock_dq_uninit(&ip->i_qadata->qa_qd_ghs[x]);
 		gfs2_quota_unhold(ip);
 	}
 
@@ -1082,14 +1115,14 @@ void gfs2_quota_unlock(struct gfs2_inode *ip)
 	if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
 		goto out;
 
-	for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
+	for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
 		struct gfs2_quota_data *qd;
 		int sync;
 
-		qd = ip->i_res->rs_qa_qd[x];
+		qd = ip->i_qadata->qa_qd[x];
 		sync = need_sync(qd);
 
-		gfs2_glock_dq_uninit(&ip->i_res->rs_qa_qd_ghs[x]);
+		gfs2_glock_dq_uninit(&ip->i_qadata->qa_qd_ghs[x]);
 		if (!sync)
 			continue;
 
@@ -1168,8 +1201,8 @@ int gfs2_quota_check(struct gfs2_inode *ip, kuid_t uid, kgid_t gid,
         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
                 return 0;
 
-	for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
-		qd = ip->i_res->rs_qa_qd[x];
+	for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
+		qd = ip->i_qadata->qa_qd[x];
 
 		if (!(qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
 		      qid_eq(qd->qd_id, make_kqid_gid(gid))))
@@ -1217,14 +1250,16 @@ void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
 {
 	struct gfs2_quota_data *qd;
 	unsigned int x;
+	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 
-	if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), change))
+	if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON ||
+	    gfs2_assert_warn(sdp, change))
 		return;
 	if (ip->i_diskflags & GFS2_DIF_SYSTEM)
 		return;
 
-	for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
-		qd = ip->i_res->rs_qa_qd[x];
+	for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
+		qd = ip->i_qadata->qa_qd[x];
 
 		if (qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
 		    qid_eq(qd->qd_id, make_kqid_gid(gid))) {
@@ -1635,7 +1670,7 @@ static int gfs2_set_dqblk(struct super_block *sb, struct kqid qid,
 	if (error)
 		return error;
 
-	error = gfs2_rs_alloc(ip);
+	error = gfs2_rsqa_alloc(ip);
 	if (error)
 		goto out_put;