xfs: stop using q_core.d_id in the quota code

Add a dquot id field to the incore dquot, and use that instead of the
one in qcore.  This eliminates a bunch of endian conversions and will
eventually allow us to remove qcore entirely.

We also rearrange the start of xfs_dquot to remove padding holes, saving
8 bytes.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
diff --git a/fs/xfs/xfs_qm.c b/fs/xfs/xfs_qm.c
index f80bcba..a2a860a 100644
--- a/fs/xfs/xfs_qm.c
+++ b/fs/xfs/xfs_qm.c
@@ -79,7 +79,7 @@ xfs_qm_dquot_walk(
 		for (i = 0; i < nr_found; i++) {
 			struct xfs_dquot *dqp = batch[i];
 
-			next_index = be32_to_cpu(dqp->q_core.d_id) + 1;
+			next_index = dqp->q_id + 1;
 
 			error = execute(batch[i], data);
 			if (error == -EAGAIN) {
@@ -161,8 +161,7 @@ xfs_qm_dqpurge(
 	xfs_dqfunlock(dqp);
 	xfs_dqunlock(dqp);
 
-	radix_tree_delete(xfs_dquot_tree(qi, dqp->q_core.d_flags),
-			  be32_to_cpu(dqp->q_core.d_id));
+	radix_tree_delete(xfs_dquot_tree(qi, dqp->q_core.d_flags), dqp->q_id);
 	qi->qi_dquots--;
 
 	/*
@@ -1108,7 +1107,7 @@ xfs_qm_quotacheck_dqadjust(
 	 *
 	 * There are no timers for the default values set in the root dquot.
 	 */
-	if (dqp->q_core.d_id) {
+	if (dqp->q_id) {
 		xfs_qm_adjust_dqlimits(mp, dqp);
 		xfs_qm_adjust_dqtimers(mp, dqp);
 	}
@@ -1594,8 +1593,7 @@ xfs_qm_dqfree_one(
 	struct xfs_quotainfo	*qi = mp->m_quotainfo;
 
 	mutex_lock(&qi->qi_tree_lock);
-	radix_tree_delete(xfs_dquot_tree(qi, dqp->q_core.d_flags),
-			  be32_to_cpu(dqp->q_core.d_id));
+	radix_tree_delete(xfs_dquot_tree(qi, dqp->q_core.d_flags), dqp->q_id);
 
 	qi->qi_dquots--;
 	mutex_unlock(&qi->qi_tree_lock);
@@ -1819,7 +1817,7 @@ xfs_qm_vop_chown_reserve(
 			XFS_QMOPT_RES_RTBLKS : XFS_QMOPT_RES_REGBLKS;
 
 	if (XFS_IS_UQUOTA_ON(mp) && udqp &&
-	    i_uid_read(VFS_I(ip)) != be32_to_cpu(udqp->q_core.d_id)) {
+	    i_uid_read(VFS_I(ip)) != udqp->q_id) {
 		udq_delblks = udqp;
 		/*
 		 * If there are delayed allocation blocks, then we have to
@@ -1832,7 +1830,7 @@ xfs_qm_vop_chown_reserve(
 		}
 	}
 	if (XFS_IS_GQUOTA_ON(ip->i_mount) && gdqp &&
-	    i_gid_read(VFS_I(ip)) != be32_to_cpu(gdqp->q_core.d_id)) {
+	    i_gid_read(VFS_I(ip)) != gdqp->q_id) {
 		gdq_delblks = gdqp;
 		if (delblks) {
 			ASSERT(ip->i_gdquot);
@@ -1841,7 +1839,7 @@ xfs_qm_vop_chown_reserve(
 	}
 
 	if (XFS_IS_PQUOTA_ON(ip->i_mount) && pdqp &&
-	    ip->i_d.di_projid != be32_to_cpu(pdqp->q_core.d_id)) {
+	    ip->i_d.di_projid != pdqp->q_id) {
 		pdq_delblks = pdqp;
 		if (delblks) {
 			ASSERT(ip->i_pdquot);
@@ -1925,21 +1923,21 @@ xfs_qm_vop_create_dqattach(
 
 	if (udqp && XFS_IS_UQUOTA_ON(mp)) {
 		ASSERT(ip->i_udquot == NULL);
-		ASSERT(i_uid_read(VFS_I(ip)) == be32_to_cpu(udqp->q_core.d_id));
+		ASSERT(i_uid_read(VFS_I(ip)) == udqp->q_id);
 
 		ip->i_udquot = xfs_qm_dqhold(udqp);
 		xfs_trans_mod_dquot(tp, udqp, XFS_TRANS_DQ_ICOUNT, 1);
 	}
 	if (gdqp && XFS_IS_GQUOTA_ON(mp)) {
 		ASSERT(ip->i_gdquot == NULL);
-		ASSERT(i_gid_read(VFS_I(ip)) == be32_to_cpu(gdqp->q_core.d_id));
+		ASSERT(i_gid_read(VFS_I(ip)) == gdqp->q_id);
 
 		ip->i_gdquot = xfs_qm_dqhold(gdqp);
 		xfs_trans_mod_dquot(tp, gdqp, XFS_TRANS_DQ_ICOUNT, 1);
 	}
 	if (pdqp && XFS_IS_PQUOTA_ON(mp)) {
 		ASSERT(ip->i_pdquot == NULL);
-		ASSERT(ip->i_d.di_projid == be32_to_cpu(pdqp->q_core.d_id));
+		ASSERT(ip->i_d.di_projid == pdqp->q_id);
 
 		ip->i_pdquot = xfs_qm_dqhold(pdqp);
 		xfs_trans_mod_dquot(tp, pdqp, XFS_TRANS_DQ_ICOUNT, 1);