Now that we do not allow i_count to drop to 0 and be used we can convert
it to a refcount_t and benefit from the protections those helpers add.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 arch/powerpc/platforms/cell/spufs/file.c |  2 +-
 fs/btrfs/inode.c                         |  4 ++--
 fs/ceph/mds_client.c                     |  2 +-
 fs/ext4/ialloc.c                         |  4 ++--
 fs/fs-writeback.c                        |  2 +-
 fs/hpfs/inode.c                          |  2 +-
 fs/inode.c                               | 11 ++++++-----
 fs/nfs/inode.c                           |  4 ++--
 fs/notify/fsnotify.c                     |  2 +-
 fs/ubifs/super.c                         |  2 +-
 fs/xfs/xfs_inode.c                       |  2 +-
 fs/xfs/xfs_trace.h                       |  2 +-
 include/linux/fs.h                       |  4 ++--
 include/trace/events/filelock.h          |  2 +-
 security/landlock/fs.c                   |  2 +-
 15 files changed, 24 insertions(+), 23 deletions(-)

diff --git a/arch/powerpc/platforms/cell/spufs/file.c b/arch/powerpc/platforms/cell/spufs/file.c
index d5a2c77bc908..3f768b003838 100644
--- a/arch/powerpc/platforms/cell/spufs/file.c
+++ b/arch/powerpc/platforms/cell/spufs/file.c
@@ -1430,7 +1430,7 @@ static int spufs_mfc_open(struct inode *inode, struct file *file)
 	if (ctx->owner != current->mm)
 		return -EINVAL;
 
-	if (atomic_read(&inode->i_count) != 1)
+	if (refcount_read(&inode->i_count) != 1)
 		return -EBUSY;
 
 	mutex_lock(&ctx->mapping_lock);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index bbbcd96e8f5c..e85e38df3ea0 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -3418,7 +3418,7 @@ void btrfs_add_delayed_iput(struct btrfs_inode *inode)
 	struct btrfs_fs_info *fs_info = inode->root->fs_info;
 	unsigned long flags;
 
-	if (atomic_add_unless(&inode->vfs_inode.i_count, -1, 1)) {
+	if (refcount_dec_not_one(&inode->vfs_inode.i_count)) {
 		iobj_put(&inode->vfs_inode);
 		return;
 	}
@@ -4559,7 +4559,7 @@ static void btrfs_prune_dentries(struct btrfs_root *root)
 
 	inode = btrfs_find_first_inode(root, min_ino);
 	while (inode) {
-		if (atomic_read(&inode->vfs_inode.i_count) > 1)
+		if (refcount_read(&inode->vfs_inode.i_count) > 1)
 			d_prune_aliases(&inode->vfs_inode);
 
 		min_ino = btrfs_ino(inode) + 1;
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 0f497c39ff82..ff666d18f6ad 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -2221,7 +2221,7 @@ static int trim_caps_cb(struct inode *inode, int mds, void *arg)
 			int count;
 			dput(dentry);
 			d_prune_aliases(inode);
-			count = atomic_read(&inode->i_count);
+			count = refcount_read(&inode->i_count);
 			if (count == 1)
 				(*remaining)--;
 			doutc(cl, "%p %llx.%llx cap %p pruned, count now %d\n",
diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index df4051613b29..9a3c7f22a57e 100644
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -252,10 +252,10 @@ void ext4_free_inode(handle_t *handle, struct inode *inode)
 		       "nonexistent device\n", __func__, __LINE__);
 		return;
 	}
-	if (atomic_read(&inode->i_count) > 1) {
+	if (refcount_read(&inode->i_count) > 1) {
 		ext4_msg(sb, KERN_ERR, "%s:%d: inode #%lu: count=%d",
 			 __func__, __LINE__, inode->i_ino,
-			 atomic_read(&inode->i_count));
+			 refcount_read(&inode->i_count));
 		return;
 	}
 	if (inode->i_nlink) {
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 111a9d8215bf..789c4228412c 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -1796,7 +1796,7 @@ static int writeback_single_inode(struct inode *inode,
 	int ret = 0;
 
 	spin_lock(&inode->i_lock);
-	if (!atomic_read(&inode->i_count))
+	if (!refcount_read(&inode->i_count))
 		WARN_ON(!(inode->i_state & (I_WILL_FREE|I_FREEING)));
 	else
 		WARN_ON(inode->i_state & I_WILL_FREE);
diff --git a/fs/hpfs/inode.c b/fs/hpfs/inode.c
index a59e8fa630db..ee23a941d8f5 100644
--- a/fs/hpfs/inode.c
+++ b/fs/hpfs/inode.c
@@ -184,7 +184,7 @@ void hpfs_write_inode(struct inode *i)
 	struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
 	struct inode *parent;
 	if (i->i_ino == hpfs_sb(i->i_sb)->sb_root) return;
-	if (hpfs_inode->i_rddir_off && !atomic_read(&i->i_count)) {
+	if (hpfs_inode->i_rddir_off && !refcount_read(&i->i_count)) {
 		if (*hpfs_inode->i_rddir_off)
 			pr_err("write_inode: some position still there\n");
 		kfree(hpfs_inode->i_rddir_off);
diff --git a/fs/inode.c b/fs/inode.c
index 07c8edb4b58a..28d197731914 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -236,7 +236,7 @@ int inode_init_always_gfp(struct super_block *sb, struct inode *inode, gfp_t gfp
 	inode->i_state = 0;
 	atomic64_set(&inode->i_sequence, 0);
 	refcount_set(&inode->i_obj_count, 1);
-	atomic_set(&inode->i_count, 1);
+	refcount_set(&inode->i_count, 1);
 	inode->i_op = &empty_iops;
 	inode->i_fop = &no_open_fops;
 	inode->i_ino = 0;
@@ -561,7 +561,8 @@ static void init_once(void *foo)
 void ihold(struct inode *inode)
 {
 	iobj_get(inode);
-	WARN_ON(atomic_inc_return(&inode->i_count) < 2);
+	refcount_inc(&inode->i_count);
+	WARN_ON(refcount_read(&inode->i_count) < 2);
 }
 EXPORT_SYMBOL(ihold);
 
@@ -614,7 +615,7 @@ static void __inode_add_lru(struct inode *inode, bool rotate)
 
 	if (inode->i_state & (I_FREEING | I_WILL_FREE))
 		return;
-	if (atomic_read(&inode->i_count) != 1)
+	if (refcount_read(&inode->i_count) != 1)
 		return;
 	if (inode->__i_nlink == 0)
 		return;
@@ -2019,7 +2020,7 @@ static void __iput(struct inode *inode, bool skip_lru)
 		return;
 	BUG_ON(inode->i_state & I_CLEAR);
 
-	if (atomic_add_unless(&inode->i_count, -1, 1)) {
+	if (refcount_dec_not_one(&inode->i_count)) {
 		iobj_put(inode);
 		return;
 	}
@@ -2039,7 +2040,7 @@ static void __iput(struct inode *inode, bool skip_lru)
 	 */
 	drop = maybe_add_lru(inode, skip_lru);
 
-	if (atomic_dec_and_test(&inode->i_count))
+	if (refcount_dec_and_test(&inode->i_count))
 		iput_final(inode, drop);
 	else
 		spin_unlock(&inode->i_lock);
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 338ef77ae423..9cc84f0afa9a 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -608,7 +608,7 @@ nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr)
 		inode->i_sb->s_id,
 		(unsigned long long)NFS_FILEID(inode),
 		nfs_display_fhandle_hash(fh),
-		atomic_read(&inode->i_count));
+		refcount_read(&inode->i_count));
 
 out:
 	return inode;
@@ -2229,7 +2229,7 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
 	dfprintk(VFS, "NFS: %s(%s/%lu fh_crc=0x%08x ct=%d info=0x%llx)\n",
 			__func__, inode->i_sb->s_id, inode->i_ino,
 			nfs_display_fhandle_hash(NFS_FH(inode)),
-			atomic_read(&inode->i_count), fattr->valid);
+			refcount_read(&inode->i_count), fattr->valid);
 
 	if (!(fattr->valid & NFS_ATTR_FATTR_FILEID)) {
 		/* Only a mounted-on-fileid? Just exit */
diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c
index 079b868552c2..0883696f873d 100644
--- a/fs/notify/fsnotify.c
+++ b/fs/notify/fsnotify.c
@@ -66,7 +66,7 @@ static void fsnotify_unmount_inodes(struct super_block *sb)
 		 * removed all zero refcount inodes, in any case.  Test to
 		 * be sure.
 		 */
-		if (!atomic_read(&inode->i_count)) {
+		if (!refcount_read(&inode->i_count)) {
 			spin_unlock(&inode->i_lock);
 			continue;
 		}
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index f3e3b2068608..79526f71fa8a 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -358,7 +358,7 @@ static void ubifs_evict_inode(struct inode *inode)
 		goto out;
 
 	dbg_gen("inode %lu, mode %#x", inode->i_ino, (int)inode->i_mode);
-	ubifs_assert(c, !atomic_read(&inode->i_count));
+	ubifs_assert(c, !refcount_read(&inode->i_count));
 
 	truncate_inode_pages_final(&inode->i_data);
 
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index 9c39251961a3..06af749fe5f3 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -1035,7 +1035,7 @@ xfs_itruncate_extents_flags(
 	int			error = 0;
 
 	xfs_assert_ilocked(ip, XFS_ILOCK_EXCL);
-	if (atomic_read(&VFS_I(ip)->i_count))
+	if (refcount_read(&VFS_I(ip)->i_count))
 		xfs_assert_ilocked(ip, XFS_IOLOCK_EXCL);
 	ASSERT(new_size <= XFS_ISIZE(ip));
 	ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
index ac344e42846c..167d33b8095c 100644
--- a/fs/xfs/xfs_trace.h
+++ b/fs/xfs/xfs_trace.h
@@ -1152,7 +1152,7 @@ DECLARE_EVENT_CLASS(xfs_iref_class,
 	TP_fast_assign(
 		__entry->dev = VFS_I(ip)->i_sb->s_dev;
 		__entry->ino = ip->i_ino;
-		__entry->count = atomic_read(&VFS_I(ip)->i_count);
+		__entry->count = refcount_read(&VFS_I(ip)->i_count);
 		__entry->pincount = atomic_read(&ip->i_pincount);
 		__entry->iflags = ip->i_flags;
 		__entry->caller_ip = caller_ip;
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 8384ed81a5ad..34fb40ba8a94 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -880,7 +880,7 @@ struct inode {
 	};
 	atomic64_t		i_version;
 	atomic64_t		i_sequence; /* see futex */
-	atomic_t		i_count;
+	refcount_t		i_count;
 	atomic_t		i_dio_count;
 	atomic_t		i_writecount;
 #if defined(CONFIG_IMA) || defined(CONFIG_FILE_LOCKING)
@@ -3399,7 +3399,7 @@ static inline void iobj_get(struct inode *inode)
 static inline void __iget(struct inode *inode)
 {
 	iobj_get(inode);
-	atomic_inc(&inode->i_count);
+	refcount_inc(&inode->i_count);
 }
 
 extern void iget_failed(struct inode *);
diff --git a/include/trace/events/filelock.h b/include/trace/events/filelock.h
index b8d1e00a7982..e745436cfcd2 100644
--- a/include/trace/events/filelock.h
+++ b/include/trace/events/filelock.h
@@ -189,7 +189,7 @@ TRACE_EVENT(generic_add_lease,
 		__entry->i_ino = inode->i_ino;
 		__entry->wcount = atomic_read(&inode->i_writecount);
 		__entry->rcount = atomic_read(&inode->i_readcount);
-		__entry->icount = atomic_read(&inode->i_count);
+		__entry->icount = refcount_read(&inode->i_count);
 		__entry->owner = fl->c.flc_owner;
 		__entry->flags = fl->c.flc_flags;
 		__entry->type = fl->c.flc_type;
diff --git a/security/landlock/fs.c b/security/landlock/fs.c
index c04f8879ad03..570f851dc469 100644
--- a/security/landlock/fs.c
+++ b/security/landlock/fs.c
@@ -1281,7 +1281,7 @@ static void hook_sb_delete(struct super_block *const sb)
 		struct landlock_object *object;
 
 		/* Only handles referenced inodes. */
-		if (!atomic_read(&inode->i_count))
+		if (!refcount_read(&inode->i_count))
 			continue;
 
 		/*
-- 
2.49.0