ceph: adjust 36 checks for NULL pointers

The script “checkpatch.pl” pointed information out like the following.

Comparison to NULL could be written ...

Thus fix the affected source code places.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Reviewed-by: Yan, Zheng <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

fs/ceph/addr.c

@@ -540,7 +540,7 @@ static int writepage_nounlock(struct page *page, struct writeback_control *wbc)
 
 	/* verify this is a writeable snap context */
 	snapc = page_snap_context(page);
-	if (snapc == NULL) {
+	if (!snapc) {
 		dout("writepage %p page %p not dirty?\n", inode, page);
 		return 0;
 	}

fs/ceph/cache.c

@@ -240,7 +240,7 @@ void ceph_fscache_register_inode_cookie(struct inode *inode)
 	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
 
 	/* No caching for filesystem */
-	if (fsc->fscache == NULL)
+	if (!fsc->fscache)
 		return;
 
 	/* Only cache for regular files that are read only */

fs/ceph/caps.c

@@ -611,7 +611,7 @@ void ceph_add_cap(struct inode *inode,
 	}
 
 	if (flags & CEPH_CAP_FLAG_AUTH) {
-		if (ci->i_auth_cap == NULL ||
+		if (!ci->i_auth_cap ||
 		    ceph_seq_cmp(ci->i_auth_cap->mseq, mseq) < 0) {
 			ci->i_auth_cap = cap;
 			cap->mds_wanted = wanted;
@@ -728,7 +728,7 @@ static void __touch_cap(struct ceph_cap *cap)
 	struct ceph_mds_session *s = cap->session;
 
 	spin_lock(&s->s_cap_lock);
-	if (s->s_cap_iterator == NULL) {
+	if (!s->s_cap_iterator) {
 		dout("__touch_cap %p cap %p mds%d\n", &cap->ci->vfs_inode, cap,
 		     s->s_mds);
 		list_move_tail(&cap->session_caps, &s->s_caps);

fs/ceph/debugfs.c

@@ -24,7 +24,7 @@ static int mdsmap_show(struct seq_file *s, void *p)
 	struct ceph_fs_client *fsc = s->private;
 	struct ceph_mdsmap *mdsmap;
 
-	if (fsc->mdsc == NULL || fsc->mdsc->mdsmap == NULL)
+	if (!fsc->mdsc || !fsc->mdsc->mdsmap)
 		return 0;
 	mdsmap = fsc->mdsc->mdsmap;
 	seq_printf(s, "epoch %d\n", mdsmap->m_epoch);

fs/ceph/file.c

@@ -175,7 +175,7 @@ static int ceph_init_file(struct inode *inode, struct file *file, int fmode)
 		dout("init_file %p %p 0%o (regular)\n", inode, file,
 		     inode->i_mode);
 		cf = kmem_cache_zalloc(ceph_file_cachep, GFP_KERNEL);
-		if (cf == NULL) {
+		if (!cf) {
 			ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
 			return -ENOMEM;
 		}

fs/ceph/inode.c

@@ -52,7 +52,7 @@ struct inode *ceph_get_inode(struct super_block *sb, struct ceph_vino vino)
 	ino_t t = ceph_vino_to_ino(vino);
 
 	inode = iget5_locked(sb, t, ceph_ino_compare, ceph_set_ino_cb, &vino);
-	if (inode == NULL)
+	if (!inode)
 		return ERR_PTR(-ENOMEM);
 	if (inode->i_state & I_NEW) {
 		dout("get_inode created new inode %p %llx.%llx ino %llx\n",
@@ -1173,7 +1173,7 @@ int ceph_fill_trace(struct super_block *sb, struct ceph_mds_request *req)
 				dn = d_alloc(parent, &dname);
 				dout("d_alloc %p '%.*s' = %p\n", parent,
 				     dname.len, dname.name, dn);
-				if (dn == NULL) {
+				if (!dn) {
 					dput(parent);
 					err = -ENOMEM;
 					goto done;
@@ -1562,7 +1562,7 @@ int ceph_readdir_prepopulate(struct ceph_mds_request *req,
 			dn = d_alloc(parent, &dname);
 			dout("d_alloc %p '%.*s' = %p\n", parent,
 			     dname.len, dname.name, dn);
-			if (dn == NULL) {
+			if (!dn) {
 				dout("d_alloc badness\n");
 				err = -ENOMEM;
 				goto out;

fs/ceph/mds_client.c

@@ -408,7 +408,7 @@ struct ceph_mds_session *__ceph_lookup_mds_session(struct ceph_mds_client *mdsc,
 {
 	struct ceph_mds_session *session;
 
-	if (mds >= mdsc->max_sessions || mdsc->sessions[mds] == NULL)
+	if (mds >= mdsc->max_sessions || !mdsc->sessions[mds])
 		return NULL;
 	session = mdsc->sessions[mds];
 	dout("lookup_mds_session %p %d\n", session,
@@ -483,7 +483,7 @@ static struct ceph_mds_session *register_session(struct ceph_mds_client *mdsc,
 
 		dout("register_session realloc to %d\n", newmax);
 		sa = kcalloc(newmax, sizeof(void *), GFP_NOFS);
-		if (sa == NULL)
+		if (!sa)
 			goto fail_realloc;
 		if (mdsc->sessions) {
 			memcpy(sa, mdsc->sessions,
@@ -893,7 +893,7 @@ static struct ceph_msg *create_session_open_msg(struct ceph_mds_client *mdsc, u6
 
 	/* Calculate serialized length of metadata */
 	metadata_bytes = 4;  /* map length */
-	for (i = 0; metadata[i][0] != NULL; ++i) {
+	for (i = 0; metadata[i][0]; ++i) {
 		metadata_bytes += 8 + strlen(metadata[i][0]) +
 			strlen(metadata[i][1]);
 		metadata_key_count++;
@@ -926,7 +926,7 @@ static struct ceph_msg *create_session_open_msg(struct ceph_mds_client *mdsc, u6
 	ceph_encode_32(&p, metadata_key_count);
 
 	/* Two length-prefixed strings for each entry in the map */
-	for (i = 0; metadata[i][0] != NULL; ++i) {
+	for (i = 0; metadata[i][0]; ++i) {
 		size_t const key_len = strlen(metadata[i][0]);
 		size_t const val_len = strlen(metadata[i][1]);
 
@@ -1129,7 +1129,7 @@ static int iterate_session_caps(struct ceph_mds_session *session,
 
 		spin_lock(&session->s_cap_lock);
 		p = p->next;
-		if (cap->ci == NULL) {
+		if (!cap->ci) {
 			dout("iterate_session_caps  finishing cap %p removal\n",
 			     cap);
 			BUG_ON(cap->session != session);
@@ -1755,7 +1755,7 @@ char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *base,
 	int len, pos;
 	unsigned seq;
 
-	if (dentry == NULL)
+	if (!dentry)
 		return ERR_PTR(-EINVAL);
 
 retry:
@@ -1778,7 +1778,7 @@ char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *base,
 		len--;  /* no leading '/' */
 
 	path = kmalloc(len+1, GFP_NOFS);
-	if (path == NULL)
+	if (!path)
 		return ERR_PTR(-ENOMEM);
 	pos = len;
 	path[pos] = 0;	/* trailing null */
@@ -3140,7 +3140,7 @@ static void check_new_map(struct ceph_mds_client *mdsc,
 	     newmap->m_epoch, oldmap->m_epoch);
 
 	for (i = 0; i < oldmap->m_num_mds && i < mdsc->max_sessions; i++) {
-		if (mdsc->sessions[i] == NULL)
+		if (!mdsc->sessions[i])
 			continue;
 		s = mdsc->sessions[i];
 		oldstate = ceph_mdsmap_get_state(oldmap, i);
@@ -3287,7 +3287,7 @@ static void handle_lease(struct ceph_mds_client *mdsc,
 	mutex_lock(&session->s_mutex);
 	session->s_seq++;
 
-	if (inode == NULL) {
+	if (!inode) {
 		dout("handle_lease no inode %llx\n", vino.ino);
 		goto release;
 	}
@@ -3445,7 +3445,7 @@ static void delayed_work(struct work_struct *work)
 
 	for (i = 0; i < mdsc->max_sessions; i++) {
 		struct ceph_mds_session *s = __ceph_lookup_mds_session(mdsc, i);
-		if (s == NULL)
+		if (!s)
 			continue;
 		if (s->s_state == CEPH_MDS_SESSION_CLOSING) {
 			dout("resending session close request for mds%d\n",
@@ -3497,7 +3497,7 @@ int ceph_mdsc_init(struct ceph_fs_client *fsc)
 	fsc->mdsc = mdsc;
 	mutex_init(&mdsc->mutex);
 	mdsc->mdsmap = kzalloc(sizeof(*mdsc->mdsmap), GFP_NOFS);
-	if (mdsc->mdsmap == NULL) {
+	if (!mdsc->mdsmap) {
 		kfree(mdsc);
 		return -ENOMEM;
 	}

fs/ceph/mdsmap.c

@@ -112,7 +112,7 @@ struct ceph_mdsmap *ceph_mdsmap_decode(void **p, void *end)
 	u16 mdsmap_ev;
 
 	m = kzalloc(sizeof(*m), GFP_NOFS);
-	if (m == NULL)
+	if (!m)
 		return ERR_PTR(-ENOMEM);
 
 	ceph_decode_need(p, end, 1 + 1, bad);
@@ -138,7 +138,7 @@ struct ceph_mdsmap *ceph_mdsmap_decode(void **p, void *end)
 	m->m_num_mds = m->m_max_mds;
 
 	m->m_info = kcalloc(m->m_num_mds, sizeof(*m->m_info), GFP_NOFS);
-	if (m->m_info == NULL)
+	if (!m->m_info)
 		goto nomem;
 
 	/* pick out active nodes from mds_info (state > 0) */
@@ -232,7 +232,7 @@ struct ceph_mdsmap *ceph_mdsmap_decode(void **p, void *end)
 		if (num_export_targets) {
 			info->export_targets = kcalloc(num_export_targets,
 						       sizeof(u32), GFP_NOFS);
-			if (info->export_targets == NULL)
+			if (!info->export_targets)
 				goto nomem;
 			for (j = 0; j < num_export_targets; j++)
 				info->export_targets[j] =

fs/ceph/super.c

@@ -594,7 +594,7 @@ static struct ceph_fs_client *create_fs_client(struct ceph_mount_options *fsopt,
 	}
 	fsc->client->extra_mon_dispatch = extra_mon_dispatch;
 
-	if (fsopt->mds_namespace == NULL) {
+	if (!fsopt->mds_namespace) {
 		ceph_monc_want_map(&fsc->client->monc, CEPH_SUB_MDSMAP,
 				   0, true);
 	} else {
@@ -615,13 +615,13 @@ static struct ceph_fs_client *create_fs_client(struct ceph_mount_options *fsopt,
 	 * to be processed in parallel, limit concurrency.
 	 */
 	fsc->wb_wq = alloc_workqueue("ceph-writeback", 0, 1);
-	if (fsc->wb_wq == NULL)
+	if (!fsc->wb_wq)
 		goto fail_client;
 	fsc->pg_inv_wq = alloc_workqueue("ceph-pg-invalid", 0, 1);
-	if (fsc->pg_inv_wq == NULL)
+	if (!fsc->pg_inv_wq)
 		goto fail_wb_wq;
 	fsc->trunc_wq = alloc_workqueue("ceph-trunc", 0, 1);
-	if (fsc->trunc_wq == NULL)
+	if (!fsc->trunc_wq)
 		goto fail_pg_inv_wq;
 
 	/* set up mempools */
@@ -692,26 +692,26 @@ static int __init init_caches(void)
 				      __alignof__(struct ceph_inode_info),
 				      SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
 				      SLAB_ACCOUNT, ceph_inode_init_once);
-	if (ceph_inode_cachep == NULL)
+	if (!ceph_inode_cachep)
 		return -ENOMEM;
 
 	ceph_cap_cachep = KMEM_CACHE(ceph_cap,
 				     SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
-	if (ceph_cap_cachep == NULL)
+	if (!ceph_cap_cachep)
 		goto bad_cap;
 	ceph_cap_flush_cachep = KMEM_CACHE(ceph_cap_flush,
 					   SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
-	if (ceph_cap_flush_cachep == NULL)
+	if (!ceph_cap_flush_cachep)
 		goto bad_cap_flush;
 
 	ceph_dentry_cachep = KMEM_CACHE(ceph_dentry_info,
 					SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
-	if (ceph_dentry_cachep == NULL)
+	if (!ceph_dentry_cachep)
 		goto bad_dentry;
 
 	ceph_file_cachep = KMEM_CACHE(ceph_file_info, SLAB_MEM_SPREAD);
 
-	if (ceph_file_cachep == NULL)
+	if (!ceph_file_cachep)
 		goto bad_file;
 
 	if ((error = ceph_fscache_register()))

fs/ceph/xattr.c

@@ -777,7 +777,7 @@ ssize_t __ceph_getxattr(struct inode *inode, const char *name, void *value,
 		spin_unlock(&ci->i_ceph_lock);
 
 		/* security module gets xattr while filling trace */
-		if (current->journal_info != NULL) {
+		if (current->journal_info) {
 			pr_warn_ratelimited("sync getxattr %p "
 					    "during filling trace\n", inode);
 			return -EBUSY;
@@ -809,7 +809,7 @@ ssize_t __ceph_getxattr(struct inode *inode, const char *name, void *value,
 
 	memcpy(value, xattr->val, xattr->val_len);
 
-	if (current->journal_info != NULL &&
+	if (current->journal_info &&
 	    !strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN))
 		ci->i_ceph_flags |= CEPH_I_SEC_INITED;
 out:
@@ -1058,7 +1058,7 @@ int __ceph_setxattr(struct inode *inode, const char *name,
 		up_read(&mdsc->snap_rwsem);
 
 	/* security module set xattr while filling trace */
-	if (current->journal_info != NULL) {
+	if (current->journal_info) {
 		pr_warn_ratelimited("sync setxattr %p "
 				    "during filling trace\n", inode);
 		err = -EBUSY;
@@ -1108,7 +1108,7 @@ bool ceph_security_xattr_deadlock(struct inode *in)
 {
 	struct ceph_inode_info *ci;
 	bool ret;
-	if (in->i_security == NULL)
+	if (!in->i_security)
 		return false;
 	ci = ceph_inode(in);
 	spin_lock(&ci->i_ceph_lock);