userns: Convert struct dquot dq_id to be a struct kqid

Change struct dquot dq_id to a struct kqid and remove the now
unecessary dq_type.

Make minimal changes to dquot, quota_tree, quota_v1, quota_v2, ext3,
ext4, and ocfs2 to deal with the change in quota structures and
signatures.  The ocfs2 changes are larger than most because of the
extensive tracing throughout the ocfs2 quota code that prints out
dq_id.

quota_tree.c:get_index is modified to take a struct kqid instead of a
qid_t because all of it's callers pass in dquot->dq_id and it allows
me to introduce only a single conversion.

The rest of the changes are either just replacing dq_type with dq_id.type,
adding conversions to deal with the change in type and occassionally
adding qid_eq to allow quota id comparisons in a user namespace safe way.

Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Theodore Tso <tytso@mit.edu>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

2 files changed, 32 insertions, 22 deletions

diff --git a/fs/ocfs2/quota_global.c b/fs/ocfs2/quota_global.c
index 0a86e30..332a281 100644
--- a/fs/ocfs2/quota_global.c
+++ b/fs/ocfs2/quota_global.c
@@ -95,7 +95,7 @@ static void ocfs2_global_mem2diskdqb(void *dp, struct dquot *dquot)
 	struct ocfs2_global_disk_dqblk *d = dp;
 	struct mem_dqblk *m = &dquot->dq_dqb;
 
-	d->dqb_id = cpu_to_le32(dquot->dq_id);
+	d->dqb_id = cpu_to_le32(from_kqid(&init_user_ns, dquot->dq_id));
 	d->dqb_use_count = cpu_to_le32(OCFS2_DQUOT(dquot)->dq_use_count);
 	d->dqb_ihardlimit = cpu_to_le64(m->dqb_ihardlimit);
 	d->dqb_isoftlimit = cpu_to_le64(m->dqb_isoftlimit);
@@ -112,11 +112,14 @@ static int ocfs2_global_is_id(void *dp, struct dquot *dquot)
 {
 	struct ocfs2_global_disk_dqblk *d = dp;
 	struct ocfs2_mem_dqinfo *oinfo =
-			sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
+			sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv;
 
 	if (qtree_entry_unused(&oinfo->dqi_gi, dp))
 		return 0;
-	return le32_to_cpu(d->dqb_id) == dquot->dq_id;
+
+	return qid_eq(make_kqid(&init_user_ns, dquot->dq_id.type,
+				le32_to_cpu(d->dqb_id)),
+		      dquot->dq_id);
 }
 
 struct qtree_fmt_operations ocfs2_global_ops = {
@@ -475,7 +478,7 @@ int __ocfs2_sync_dquot(struct dquot *dquot, int freeing)
 {
 	int err, err2;
 	struct super_block *sb = dquot->dq_sb;
-	int type = dquot->dq_type;
+	int type = dquot->dq_id.type;
 	struct ocfs2_mem_dqinfo *info = sb_dqinfo(sb, type)->dqi_priv;
 	struct ocfs2_global_disk_dqblk dqblk;
 	s64 spacechange, inodechange;
@@ -504,7 +507,8 @@ int __ocfs2_sync_dquot(struct dquot *dquot, int freeing)
 	olditime = dquot->dq_dqb.dqb_itime;
 	oldbtime = dquot->dq_dqb.dqb_btime;
 	ocfs2_global_disk2memdqb(dquot, &dqblk);
-	trace_ocfs2_sync_dquot(dquot->dq_id, dquot->dq_dqb.dqb_curspace,
+	trace_ocfs2_sync_dquot(from_kqid(&init_user_ns, dquot->dq_id),
+			       dquot->dq_dqb.dqb_curspace,
 			       (long long)spacechange,
 			       dquot->dq_dqb.dqb_curinodes,
 			       (long long)inodechange);
@@ -555,8 +559,8 @@ int __ocfs2_sync_dquot(struct dquot *dquot, int freeing)
 	err = ocfs2_qinfo_lock(info, freeing);
 	if (err < 0) {
 		mlog(ML_ERROR, "Failed to lock quota info, losing quota write"
-			       " (type=%d, id=%u)\n", dquot->dq_type,
-			       (unsigned)dquot->dq_id);
+			       " (type=%d, id=%u)\n", dquot->dq_id.type,
+			       (unsigned)from_kqid(&init_user_ns, dquot->dq_id));
 		goto out;
 	}
 	if (freeing)
@@ -591,9 +595,10 @@ static int ocfs2_sync_dquot_helper(struct dquot *dquot, unsigned long type)
 	struct ocfs2_super *osb = OCFS2_SB(sb);
 	int status = 0;
 
-	trace_ocfs2_sync_dquot_helper(dquot->dq_id, dquot->dq_type,
+	trace_ocfs2_sync_dquot_helper(from_kqid(&init_user_ns, dquot->dq_id),
+				      dquot->dq_id.type,
 				      type, sb->s_id);
-	if (type != dquot->dq_type)
+	if (type != dquot->dq_id.type)
 		goto out;
 	status = ocfs2_lock_global_qf(oinfo, 1);
 	if (status < 0)
@@ -643,7 +648,8 @@ static int ocfs2_write_dquot(struct dquot *dquot)
 	struct ocfs2_super *osb = OCFS2_SB(dquot->dq_sb);
 	int status = 0;
 
-	trace_ocfs2_write_dquot(dquot->dq_id, dquot->dq_type);
+	trace_ocfs2_write_dquot(from_kqid(&init_user_ns, dquot->dq_id),
+				dquot->dq_id.type);
 
 	handle = ocfs2_start_trans(osb, OCFS2_QWRITE_CREDITS);
 	if (IS_ERR(handle)) {
@@ -677,11 +683,12 @@ static int ocfs2_release_dquot(struct dquot *dquot)
 {
 	handle_t *handle;
 	struct ocfs2_mem_dqinfo *oinfo =
-			sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
+			sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv;
 	struct ocfs2_super *osb = OCFS2_SB(dquot->dq_sb);
 	int status = 0;
 
-	trace_ocfs2_release_dquot(dquot->dq_id, dquot->dq_type);
+	trace_ocfs2_release_dquot(from_kqid(&init_user_ns, dquot->dq_id),
+				  dquot->dq_id.type);
 
 	mutex_lock(&dquot->dq_lock);
 	/* Check whether we are not racing with some other dqget() */
@@ -691,7 +698,7 @@ static int ocfs2_release_dquot(struct dquot *dquot)
 	if (status < 0)
 		goto out;
 	handle = ocfs2_start_trans(osb,
-		ocfs2_calc_qdel_credits(dquot->dq_sb, dquot->dq_type));
+		ocfs2_calc_qdel_credits(dquot->dq_sb, dquot->dq_id.type));
 	if (IS_ERR(handle)) {
 		status = PTR_ERR(handle);
 		mlog_errno(status);
@@ -733,13 +740,14 @@ static int ocfs2_acquire_dquot(struct dquot *dquot)
 	int ex = 0;
 	struct super_block *sb = dquot->dq_sb;
 	struct ocfs2_super *osb = OCFS2_SB(sb);
-	int type = dquot->dq_type;
+	int type = dquot->dq_id.type;
 	struct ocfs2_mem_dqinfo *info = sb_dqinfo(sb, type)->dqi_priv;
 	struct inode *gqinode = info->dqi_gqinode;
 	int need_alloc = ocfs2_global_qinit_alloc(sb, type);
 	handle_t *handle;
 
-	trace_ocfs2_acquire_dquot(dquot->dq_id, type);
+	trace_ocfs2_acquire_dquot(from_kqid(&init_user_ns, dquot->dq_id),
+				  type);
 	mutex_lock(&dquot->dq_lock);
 	/*
 	 * We need an exclusive lock, because we're going to update use count
@@ -821,12 +829,13 @@ static int ocfs2_mark_dquot_dirty(struct dquot *dquot)
 	int sync = 0;
 	int status;
 	struct super_block *sb = dquot->dq_sb;
-	int type = dquot->dq_type;
+	int type = dquot->dq_id.type;
 	struct ocfs2_mem_dqinfo *oinfo = sb_dqinfo(sb, type)->dqi_priv;
 	handle_t *handle;
 	struct ocfs2_super *osb = OCFS2_SB(sb);
 
-	trace_ocfs2_mark_dquot_dirty(dquot->dq_id, type);
+	trace_ocfs2_mark_dquot_dirty(from_kqid(&init_user_ns, dquot->dq_id),
+				     type);
 
 	/* In case user set some limits, sync dquot immediately to global
 	 * quota file so that information propagates quicker */
diff --git a/fs/ocfs2/quota_local.c b/fs/ocfs2/quota_local.c
index 020f0ba..27fe7ee 100644
--- a/fs/ocfs2/quota_local.c
+++ b/fs/ocfs2/quota_local.c
@@ -883,7 +883,8 @@ static void olq_set_dquot(struct buffer_head *bh, void *private)
 	dqblk = (struct ocfs2_local_disk_dqblk *)(bh->b_data
 		+ ol_dqblk_block_offset(sb, od->dq_local_off));
 
-	dqblk->dqb_id = cpu_to_le64(od->dq_dquot.dq_id);
+	dqblk->dqb_id = cpu_to_le64(from_kqid(&init_user_ns,
+					      od->dq_dquot.dq_id));
 	spin_lock(&dq_data_lock);
 	dqblk->dqb_spacemod = cpu_to_le64(od->dq_dquot.dq_dqb.dqb_curspace -
 					  od->dq_origspace);
@@ -893,7 +894,7 @@ static void olq_set_dquot(struct buffer_head *bh, void *private)
 	trace_olq_set_dquot(
 		(unsigned long long)le64_to_cpu(dqblk->dqb_spacemod),
 		(unsigned long long)le64_to_cpu(dqblk->dqb_inodemod),
-		od->dq_dquot.dq_id);
+		from_kqid(&init_user_ns, od->dq_dquot.dq_id));
 }
 
 /* Write dquot to local quota file */
@@ -902,7 +903,7 @@ int ocfs2_local_write_dquot(struct dquot *dquot)
 	struct super_block *sb = dquot->dq_sb;
 	struct ocfs2_dquot *od = OCFS2_DQUOT(dquot);
 	struct buffer_head *bh;
-	struct inode *lqinode = sb_dqopt(sb)->files[dquot->dq_type];
+	struct inode *lqinode = sb_dqopt(sb)->files[dquot->dq_id.type];
 	int status;
 
 	status = ocfs2_read_quota_phys_block(lqinode, od->dq_local_phys_blk,
@@ -1223,7 +1224,7 @@ static void olq_alloc_dquot(struct buffer_head *bh, void *private)
 int ocfs2_create_local_dquot(struct dquot *dquot)
 {
 	struct super_block *sb = dquot->dq_sb;
-	int type = dquot->dq_type;
+	int type = dquot->dq_id.type;
 	struct inode *lqinode = sb_dqopt(sb)->files[type];
 	struct ocfs2_quota_chunk *chunk;
 	struct ocfs2_dquot *od = OCFS2_DQUOT(dquot);
@@ -1277,7 +1278,7 @@ out:
 int ocfs2_local_release_dquot(handle_t *handle, struct dquot *dquot)
 {
 	int status;
-	int type = dquot->dq_type;
+	int type = dquot->dq_id.type;
 	struct ocfs2_dquot *od = OCFS2_DQUOT(dquot);
 	struct super_block *sb = dquot->dq_sb;
 	struct ocfs2_local_disk_chunk *dchunk;