Merge tag 'v5.0-rc6' into sched/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>

43 files changed, 496 insertions, 205 deletions

diff --git a/fs/aio.c b/fs/aio.c
index b906ff70c90f..aaaaf4d12c73 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -1436,6 +1436,7 @@ static int aio_prep_rw(struct kiocb *req, const struct iocb *iocb)
 	if (unlikely(!req->ki_filp))
 		return -EBADF;
 	req->ki_complete = aio_complete_rw;
+	req->private = NULL;
 	req->ki_pos = iocb->aio_offset;
 	req->ki_flags = iocb_flags(req->ki_filp);
 	if (iocb->aio_flags & IOCB_FLAG_RESFD)
diff --git a/fs/autofs/expire.c b/fs/autofs/expire.c
index d441244b79df..28d9c2b1b3bb 100644
--- a/fs/autofs/expire.c
+++ b/fs/autofs/expire.c
@@ -596,7 +596,6 @@ int autofs_expire_run(struct super_block *sb,
 	pkt.len = dentry->d_name.len;
 	memcpy(pkt.name, dentry->d_name.name, pkt.len);
 	pkt.name[pkt.len] = '\0';
-	dput(dentry);
 
 	if (copy_to_user(pkt_p, &pkt, sizeof(struct autofs_packet_expire)))
 		ret = -EFAULT;
@@ -609,6 +608,8 @@ int autofs_expire_run(struct super_block *sb,
 	complete_all(&ino->expire_complete);
 	spin_unlock(&sbi->fs_lock);
 
+	dput(dentry);
+
 	return ret;
 }
 
diff --git a/fs/autofs/inode.c b/fs/autofs/inode.c
index 0e8ea2d9a2bb..078992eee299 100644
--- a/fs/autofs/inode.c
+++ b/fs/autofs/inode.c
@@ -266,8 +266,10 @@ int autofs_fill_super(struct super_block *s, void *data, int silent)
 	}
 	root_inode = autofs_get_inode(s, S_IFDIR | 0755);
 	root = d_make_root(root_inode);
-	if (!root)
+	if (!root) {
+		ret = -ENOMEM;
 		goto fail_ino;
+	}
 	pipe = NULL;
 
 	root->d_fsdata = ino;
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index f64aad613727..5a6c39b44c84 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -968,6 +968,48 @@ static noinline int update_ref_for_cow(struct btrfs_trans_handle *trans,
 	return 0;
 }
 
+static struct extent_buffer *alloc_tree_block_no_bg_flush(
+					  struct btrfs_trans_handle *trans,
+					  struct btrfs_root *root,
+					  u64 parent_start,
+					  const struct btrfs_disk_key *disk_key,
+					  int level,
+					  u64 hint,
+					  u64 empty_size)
+{
+	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct extent_buffer *ret;
+
+	/*
+	 * If we are COWing a node/leaf from the extent, chunk, device or free
+	 * space trees, make sure that we do not finish block group creation of
+	 * pending block groups. We do this to avoid a deadlock.
+	 * COWing can result in allocation of a new chunk, and flushing pending
+	 * block groups (btrfs_create_pending_block_groups()) can be triggered
+	 * when finishing allocation of a new chunk. Creation of a pending block
+	 * group modifies the extent, chunk, device and free space trees,
+	 * therefore we could deadlock with ourselves since we are holding a
+	 * lock on an extent buffer that btrfs_create_pending_block_groups() may
+	 * try to COW later.
+	 * For similar reasons, we also need to delay flushing pending block
+	 * groups when splitting a leaf or node, from one of those trees, since
+	 * we are holding a write lock on it and its parent or when inserting a
+	 * new root node for one of those trees.
+	 */
+	if (root == fs_info->extent_root ||
+	    root == fs_info->chunk_root ||
+	    root == fs_info->dev_root ||
+	    root == fs_info->free_space_root)
+		trans->can_flush_pending_bgs = false;
+
+	ret = btrfs_alloc_tree_block(trans, root, parent_start,
+				     root->root_key.objectid, disk_key, level,
+				     hint, empty_size);
+	trans->can_flush_pending_bgs = true;
+
+	return ret;
+}
+
 /*
  * does the dirty work in cow of a single block.  The parent block (if
  * supplied) is updated to point to the new cow copy.  The new buffer is marked
@@ -1015,28 +1057,8 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
 	if ((root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) && parent)
 		parent_start = parent->start;
 
-	/*
-	 * If we are COWing a node/leaf from the extent, chunk, device or free
-	 * space trees, make sure that we do not finish block group creation of
-	 * pending block groups. We do this to avoid a deadlock.
-	 * COWing can result in allocation of a new chunk, and flushing pending
-	 * block groups (btrfs_create_pending_block_groups()) can be triggered
-	 * when finishing allocation of a new chunk. Creation of a pending block
-	 * group modifies the extent, chunk, device and free space trees,
-	 * therefore we could deadlock with ourselves since we are holding a
-	 * lock on an extent buffer that btrfs_create_pending_block_groups() may
-	 * try to COW later.
-	 */
-	if (root == fs_info->extent_root ||
-	    root == fs_info->chunk_root ||
-	    root == fs_info->dev_root ||
-	    root == fs_info->free_space_root)
-		trans->can_flush_pending_bgs = false;
-
-	cow = btrfs_alloc_tree_block(trans, root, parent_start,
-			root->root_key.objectid, &disk_key, level,
-			search_start, empty_size);
-	trans->can_flush_pending_bgs = true;
+	cow = alloc_tree_block_no_bg_flush(trans, root, parent_start, &disk_key,
+					   level, search_start, empty_size);
 	if (IS_ERR(cow))
 		return PTR_ERR(cow);
 
@@ -3345,8 +3367,8 @@ static noinline int insert_new_root(struct btrfs_trans_handle *trans,
 	else
 		btrfs_node_key(lower, &lower_key, 0);
 
-	c = btrfs_alloc_tree_block(trans, root, 0, root->root_key.objectid,
-				   &lower_key, level, root->node->start, 0);
+	c = alloc_tree_block_no_bg_flush(trans, root, 0, &lower_key, level,
+					 root->node->start, 0);
 	if (IS_ERR(c))
 		return PTR_ERR(c);
 
@@ -3475,8 +3497,8 @@ static noinline int split_node(struct btrfs_trans_handle *trans,
 	mid = (c_nritems + 1) / 2;
 	btrfs_node_key(c, &disk_key, mid);
 
-	split = btrfs_alloc_tree_block(trans, root, 0, root->root_key.objectid,
-			&disk_key, level, c->start, 0);
+	split = alloc_tree_block_no_bg_flush(trans, root, 0, &disk_key, level,
+					     c->start, 0);
 	if (IS_ERR(split))
 		return PTR_ERR(split);
 
@@ -4260,8 +4282,8 @@ again:
 	else
 		btrfs_item_key(l, &disk_key, mid);
 
-	right = btrfs_alloc_tree_block(trans, root, 0, root->root_key.objectid,
-			&disk_key, 0, l->start, 0);
+	right = alloc_tree_block_no_bg_flush(trans, root, 0, &disk_key, 0,
+					     l->start, 0);
 	if (IS_ERR(right))
 		return PTR_ERR(right);
 
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index c5586ffd1426..0a3f122dd61f 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -1621,6 +1621,7 @@ static struct dentry *btrfs_mount(struct file_system_type *fs_type, int flags,
 				flags | SB_RDONLY, device_name, data);
 			if (IS_ERR(mnt_root)) {
 				root = ERR_CAST(mnt_root);
+				kfree(subvol_name);
 				goto out;
 			}
 
@@ -1630,12 +1631,14 @@ static struct dentry *btrfs_mount(struct file_system_type *fs_type, int flags,
 			if (error < 0) {
 				root = ERR_PTR(error);
 				mntput(mnt_root);
+				kfree(subvol_name);
 				goto out;
 			}
 		}
 	}
 	if (IS_ERR(mnt_root)) {
 		root = ERR_CAST(mnt_root);
+		kfree(subvol_name);
 		goto out;
 	}
 
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 127fa1535f58..4ec2b660d014 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -850,14 +850,6 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
 
 	btrfs_trans_release_chunk_metadata(trans);
 
-	if (lock && should_end_transaction(trans) &&
-	    READ_ONCE(cur_trans->state) == TRANS_STATE_RUNNING) {
-		spin_lock(&info->trans_lock);
-		if (cur_trans->state == TRANS_STATE_RUNNING)
-			cur_trans->state = TRANS_STATE_BLOCKED;
-		spin_unlock(&info->trans_lock);
-	}
-
 	if (lock && READ_ONCE(cur_trans->state) == TRANS_STATE_BLOCKED) {
 		if (throttle)
 			return btrfs_commit_transaction(trans);
@@ -1879,6 +1871,21 @@ static void cleanup_transaction(struct btrfs_trans_handle *trans, int err)
 	kmem_cache_free(btrfs_trans_handle_cachep, trans);
 }
 
+/*
+ * Release reserved delayed ref space of all pending block groups of the
+ * transaction and remove them from the list
+ */
+static void btrfs_cleanup_pending_block_groups(struct btrfs_trans_handle *trans)
+{
+       struct btrfs_fs_info *fs_info = trans->fs_info;
+       struct btrfs_block_group_cache *block_group, *tmp;
+
+       list_for_each_entry_safe(block_group, tmp, &trans->new_bgs, bg_list) {
+               btrfs_delayed_refs_rsv_release(fs_info, 1);
+               list_del_init(&block_group->bg_list);
+       }
+}
+
 static inline int btrfs_start_delalloc_flush(struct btrfs_fs_info *fs_info)
 {
 	/*
@@ -2270,6 +2277,7 @@ scrub_continue:
 	btrfs_scrub_continue(fs_info);
 cleanup_transaction:
 	btrfs_trans_release_metadata(trans);
+	btrfs_cleanup_pending_block_groups(trans);
 	btrfs_trans_release_chunk_metadata(trans);
 	trans->block_rsv = NULL;
 	btrfs_warn(fs_info, "Skipping commit of aborted transaction.");
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 3e4f8f88353e..15561926ab32 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -957,11 +957,11 @@ static noinline struct btrfs_device *device_list_add(const char *path,
 		else
 			fs_devices = alloc_fs_devices(disk_super->fsid, NULL);
 
-		fs_devices->fsid_change = fsid_change_in_progress;
-
 		if (IS_ERR(fs_devices))
 			return ERR_CAST(fs_devices);
 
+		fs_devices->fsid_change = fsid_change_in_progress;
+
 		mutex_lock(&fs_devices->device_list_mutex);
 		list_add(&fs_devices->fs_list, &fs_uuids);
 
diff --git a/fs/buffer.c b/fs/buffer.c
index 52d024bfdbc1..48318fb74938 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -200,6 +200,7 @@ __find_get_block_slow(struct block_device *bdev, sector_t block)
 	struct buffer_head *head;
 	struct page *page;
 	int all_mapped = 1;
+	static DEFINE_RATELIMIT_STATE(last_warned, HZ, 1);
 
 	index = block >> (PAGE_SHIFT - bd_inode->i_blkbits);
 	page = find_get_page_flags(bd_mapping, index, FGP_ACCESSED);
@@ -227,15 +228,15 @@ __find_get_block_slow(struct block_device *bdev, sector_t block)
 	 * file io on the block device and getblk.  It gets dealt with
 	 * elsewhere, don't buffer_error if we had some unmapped buffers
 	 */
-	if (all_mapped) {
-		printk("__find_get_block_slow() failed. "
-			"block=%llu, b_blocknr=%llu\n",
-			(unsigned long long)block,
-			(unsigned long long)bh->b_blocknr);
-		printk("b_state=0x%08lx, b_size=%zu\n",
-			bh->b_state, bh->b_size);
-		printk("device %pg blocksize: %d\n", bdev,
-			1 << bd_inode->i_blkbits);
+	ratelimit_set_flags(&last_warned, RATELIMIT_MSG_ON_RELEASE);
+	if (all_mapped && __ratelimit(&last_warned)) {
+		printk("__find_get_block_slow() failed. block=%llu, "
+		       "b_blocknr=%llu, b_state=0x%08lx, b_size=%zu, "
+		       "device %pg blocksize: %d\n",
+		       (unsigned long long)block,
+		       (unsigned long long)bh->b_blocknr,
+		       bh->b_state, bh->b_size, bdev,
+		       1 << bd_inode->i_blkbits);
 	}
 out_unlock:
 	spin_unlock(&bd_mapping->private_lock);
diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 94c026bba2c2..bba28a5034ba 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -1035,6 +1035,8 @@ static void drop_inode_snap_realm(struct ceph_inode_info *ci)
 	list_del_init(&ci->i_snap_realm_item);
 	ci->i_snap_realm_counter++;
 	ci->i_snap_realm = NULL;
+	if (realm->ino == ci->i_vino.ino)
+		realm->inode = NULL;
 	spin_unlock(&realm->inodes_with_caps_lock);
 	ceph_put_snap_realm(ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc,
 			    realm);
diff --git a/fs/ceph/quota.c b/fs/ceph/quota.c
index 03f4d24db8fe..9455d3aef0c3 100644
--- a/fs/ceph/quota.c
+++ b/fs/ceph/quota.c
@@ -3,19 +3,6 @@
  * quota.c - CephFS quota
  *
  * Copyright (C) 2017-2018 SUSE
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version 2
- * of the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, see <http://www.gnu.org/licenses/>.
  */
 
 #include <linux/statfs.h>
diff --git a/fs/cifs/cifs_debug.c b/fs/cifs/cifs_debug.c
index 593fb422d0f3..e92a2fee3c57 100644
--- a/fs/cifs/cifs_debug.c
+++ b/fs/cifs/cifs_debug.c
@@ -252,6 +252,7 @@ static int cifs_debug_data_proc_show(struct seq_file *m, void *v)
 	seq_printf(m, ",ACL");
 #endif
 	seq_putc(m, '\n');
+	seq_printf(m, "CIFSMaxBufSize: %d\n", CIFSMaxBufSize);
 	seq_printf(m, "Active VFS Requests: %d\n", GlobalTotalActiveXid);
 	seq_printf(m, "Servers:");
 
diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h
index d1f9c2f3f575..7652551a1fc4 100644
--- a/fs/cifs/cifsfs.h
+++ b/fs/cifs/cifsfs.h
@@ -150,5 +150,5 @@ extern long cifs_ioctl(struct file *filep, unsigned int cmd, unsigned long arg);
 extern const struct export_operations cifs_export_ops;
 #endif /* CONFIG_CIFS_NFSD_EXPORT */
 
-#define CIFS_VERSION   "2.16"
+#define CIFS_VERSION   "2.17"
 #endif				/* _CIFSFS_H */
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index e18915415e13..bb54ccf8481c 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -1549,18 +1549,26 @@ cifs_discard_remaining_data(struct TCP_Server_Info *server)
 }
 
 static int
-cifs_readv_discard(struct TCP_Server_Info *server, struct mid_q_entry *mid)
+__cifs_readv_discard(struct TCP_Server_Info *server, struct mid_q_entry *mid,
+		     bool malformed)
 {
 	int length;
-	struct cifs_readdata *rdata = mid->callback_data;
 
 	length = cifs_discard_remaining_data(server);
-	dequeue_mid(mid, rdata->result);
+	dequeue_mid(mid, malformed);
 	mid->resp_buf = server->smallbuf;
 	server->smallbuf = NULL;
 	return length;
 }
 
+static int
+cifs_readv_discard(struct TCP_Server_Info *server, struct mid_q_entry *mid)
+{
+	struct cifs_readdata *rdata = mid->callback_data;
+
+	return  __cifs_readv_discard(server, mid, rdata->result);
+}
+
 int
 cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid)
 {
@@ -1602,12 +1610,23 @@ cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid)
 		return -1;
 	}
 
+	/* set up first two iov for signature check and to get credits */
+	rdata->iov[0].iov_base = buf;
+	rdata->iov[0].iov_len = 4;
+	rdata->iov[1].iov_base = buf + 4;
+	rdata->iov[1].iov_len = server->total_read - 4;
+	cifs_dbg(FYI, "0: iov_base=%p iov_len=%zu\n",
+		 rdata->iov[0].iov_base, rdata->iov[0].iov_len);
+	cifs_dbg(FYI, "1: iov_base=%p iov_len=%zu\n",
+		 rdata->iov[1].iov_base, rdata->iov[1].iov_len);
+
 	/* Was the SMB read successful? */
 	rdata->result = server->ops->map_error(buf, false);
 	if (rdata->result != 0) {
 		cifs_dbg(FYI, "%s: server returned error %d\n",
 			 __func__, rdata->result);
-		return cifs_readv_discard(server, mid);
+		/* normal error on read response */
+		return __cifs_readv_discard(server, mid, false);
 	}
 
 	/* Is there enough to get to the rest of the READ_RSP header? */
@@ -1651,14 +1670,6 @@ cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid)
 		server->total_read += length;
 	}
 
-	/* set up first iov for signature check */
-	rdata->iov[0].iov_base = buf;
-	rdata->iov[0].iov_len = 4;
-	rdata->iov[1].iov_base = buf + 4;
-	rdata->iov[1].iov_len = server->total_read - 4;
-	cifs_dbg(FYI, "0: iov_base=%p iov_len=%u\n",
-		 rdata->iov[0].iov_base, server->total_read);
-
 	/* how much data is in the response? */
 #ifdef CONFIG_CIFS_SMB_DIRECT
 	use_rdma_mr = rdata->mr;
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 683310f26171..8463c940e0e5 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -720,6 +720,21 @@ server_unresponsive(struct TCP_Server_Info *server)
 	return false;
 }
 
+static inline bool
+zero_credits(struct TCP_Server_Info *server)
+{
+	int val;
+
+	spin_lock(&server->req_lock);
+	val = server->credits + server->echo_credits + server->oplock_credits;
+	if (server->in_flight == 0 && val == 0) {
+		spin_unlock(&server->req_lock);
+		return true;
+	}
+	spin_unlock(&server->req_lock);
+	return false;
+}
+
 static int
 cifs_readv_from_socket(struct TCP_Server_Info *server, struct msghdr *smb_msg)
 {
@@ -732,6 +747,12 @@ cifs_readv_from_socket(struct TCP_Server_Info *server, struct msghdr *smb_msg)
 	for (total_read = 0; msg_data_left(smb_msg); total_read += length) {
 		try_to_freeze();
 
+		/* reconnect if no credits and no requests in flight */
+		if (zero_credits(server)) {
+			cifs_reconnect(server);
+			return -ECONNABORTED;
+		}
+
 		if (server_unresponsive(server))
 			return -ECONNABORTED;
 		if (cifs_rdma_enabled(server) && server->smbd_conn)
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 2c7689f3998d..659ce1b92c44 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -2696,6 +2696,7 @@ cifs_write_from_iter(loff_t offset, size_t len, struct iov_iter *from,
 
 			rc = cifs_write_allocate_pages(wdata->pages, nr_pages);
 			if (rc) {
+				kvfree(wdata->pages);
 				kfree(wdata);
 				add_credits_and_wake_if(server, credits, 0);
 				break;
@@ -2707,6 +2708,7 @@ cifs_write_from_iter(loff_t offset, size_t len, struct iov_iter *from,
 			if (rc) {
 				for (i = 0; i < nr_pages; i++)
 					put_page(wdata->pages[i]);
+				kvfree(wdata->pages);
 				kfree(wdata);
 				add_credits_and_wake_if(server, credits, 0);
 				break;
@@ -3386,8 +3388,12 @@ cifs_send_async_read(loff_t offset, size_t len, struct cifsFileInfo *open_file,
 			}
 
 			rc = cifs_read_allocate_pages(rdata, npages);
-			if (rc)
-				goto error;
+			if (rc) {
+				kvfree(rdata->pages);
+				kfree(rdata);
+				add_credits_and_wake_if(server, credits, 0);
+				break;
+			}
 
 			rdata->tailsz = PAGE_SIZE;
 		}
@@ -3407,7 +3413,6 @@ cifs_send_async_read(loff_t offset, size_t len, struct cifsFileInfo *open_file,
 		if (!rdata->cfile->invalidHandle ||
 		    !(rc = cifs_reopen_file(rdata->cfile, true)))
 			rc = server->ops->async_readv(rdata);
-error:
 		if (rc) {
 			add_credits_and_wake_if(server, rdata->credits, 0);
 			kref_put(&rdata->refcount,
diff --git a/fs/cifs/smb2inode.c b/fs/cifs/smb2inode.c
index f14533da3a93..01a76bccdb8d 100644
--- a/fs/cifs/smb2inode.c
+++ b/fs/cifs/smb2inode.c
@@ -293,6 +293,8 @@ smb2_query_path_info(const unsigned int xid, struct cifs_tcon *tcon,
 	int rc;
 	struct smb2_file_all_info *smb2_data;
 	__u32 create_options = 0;
+	struct cifs_fid fid;
+	bool no_cached_open = tcon->nohandlecache;
 
 	*adjust_tz = false;
 	*symlink = false;
@@ -301,6 +303,21 @@ smb2_query_path_info(const unsigned int xid, struct cifs_tcon *tcon,
 			    GFP_KERNEL);
 	if (smb2_data == NULL)
 		return -ENOMEM;
+
+	/* If it is a root and its handle is cached then use it */
+	if (!strlen(full_path) && !no_cached_open) {
+		rc = open_shroot(xid, tcon, &fid);
+		if (rc)
+			goto out;
+		rc = SMB2_query_info(xid, tcon, fid.persistent_fid,
+				     fid.volatile_fid, smb2_data);
+		close_shroot(&tcon->crfid);
+		if (rc)
+			goto out;
+		move_smb2_info_to_cifs(data, smb2_data);
+		goto out;
+	}
+
 	if (backup_cred(cifs_sb))
 		create_options |= CREATE_OPEN_BACKUP_INTENT;
 
diff --git a/fs/cifs/smb2misc.c b/fs/cifs/smb2misc.c
index 6a9c47541c53..7b8b58fb4d3f 100644
--- a/fs/cifs/smb2misc.c
+++ b/fs/cifs/smb2misc.c
@@ -648,6 +648,13 @@ smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
 	if (rsp->sync_hdr.Command != SMB2_OPLOCK_BREAK)
 		return false;
 
+	if (rsp->sync_hdr.CreditRequest) {
+		spin_lock(&server->req_lock);
+		server->credits += le16_to_cpu(rsp->sync_hdr.CreditRequest);
+		spin_unlock(&server->req_lock);
+		wake_up(&server->request_q);
+	}
+
 	if (rsp->StructureSize !=
 				smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
 		if (le16_to_cpu(rsp->StructureSize) == 44)
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index cf7eb891804f..6f96e2292856 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -34,6 +34,7 @@
 #include "cifs_ioctl.h"
 #include "smbdirect.h"
 
+/* Change credits for different ops and return the total number of credits */
 static int
 change_conf(struct TCP_Server_Info *server)
 {
@@ -41,17 +42,15 @@ change_conf(struct TCP_Server_Info *server)
 	server->oplock_credits = server->echo_credits = 0;
 	switch (server->credits) {
 	case 0:
-		return -1;
+		return 0;
 	case 1:
 		server->echoes = false;
 		server->oplocks = false;
-		cifs_dbg(VFS, "disabling echoes and oplocks\n");
 		break;
 	case 2:
 		server->echoes = true;
 		server->oplocks = false;
 		server->echo_credits = 1;
-		cifs_dbg(FYI, "disabling oplocks\n");
 		break;
 	default:
 		server->echoes = true;
@@ -64,14 +63,15 @@ change_conf(struct TCP_Server_Info *server)
 		server->echo_credits = 1;
 	}
 	server->credits -= server->echo_credits + server->oplock_credits;
-	return 0;
+	return server->credits + server->echo_credits + server->oplock_credits;
 }
 
 static void
 smb2_add_credits(struct TCP_Server_Info *server, const unsigned int add,
 		 const int optype)
 {
-	int *val, rc = 0;
+	int *val, rc = -1;
+
 	spin_lock(&server->req_lock);
 	val = server->ops->get_credits_field(server, optype);
 
@@ -101,8 +101,26 @@ smb2_add_credits(struct TCP_Server_Info *server, const unsigned int add,
 	}
 	spin_unlock(&server->req_lock);
 	wake_up(&server->request_q);
-	if (rc)
-		cifs_reconnect(server);
+
+	if (server->tcpStatus == CifsNeedReconnect)
+		return;
+
+	switch (rc) {
+	case -1:
+		/* change_conf hasn't been executed */
+		break;
+	case 0:
+		cifs_dbg(VFS, "Possible client or server bug - zero credits\n");
+		break;
+	case 1:
+		cifs_dbg(VFS, "disabling echoes and oplocks\n");
+		break;
+	case 2:
+		cifs_dbg(FYI, "disabling oplocks\n");
+		break;
+	default:
+		cifs_dbg(FYI, "add %u credits total=%d\n", add, rc);
+	}
 }
 
 static void
@@ -136,7 +154,11 @@ smb2_get_credits(struct mid_q_entry *mid)
 {
 	struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)mid->resp_buf;
 
-	return le16_to_cpu(shdr->CreditRequest);
+	if (mid->mid_state == MID_RESPONSE_RECEIVED
+	    || mid->mid_state == MID_RESPONSE_MALFORMED)
+		return le16_to_cpu(shdr->CreditRequest);
+
+	return 0;
 }
 
 static int
@@ -165,14 +187,14 @@ smb2_wait_mtu_credits(struct TCP_Server_Info *server, unsigned int size,
 
 			scredits = server->credits;
 			/* can deadlock with reopen */
-			if (scredits == 1) {
+			if (scredits <= 8) {
 				*num = SMB2_MAX_BUFFER_SIZE;
 				*credits = 0;
 				break;
 			}
 
-			/* leave one credit for a possible reopen */
-			scredits--;
+			/* leave some credits for reopen and other ops */
+			scredits -= 8;
 			*num = min_t(unsigned int, size,
 				     scredits * SMB2_MAX_BUFFER_SIZE);
 
@@ -844,7 +866,9 @@ smb2_query_eas(const unsigned int xid, struct cifs_tcon *tcon,
 				      FILE_READ_EA,
 				      FILE_FULL_EA_INFORMATION,
 				      SMB2_O_INFO_FILE,
-				      SMB2_MAX_EA_BUF,
+				      CIFSMaxBufSize -
+				      MAX_SMB2_CREATE_RESPONSE_SIZE -
+				      MAX_SMB2_CLOSE_RESPONSE_SIZE,
 				      &rsp_iov, &buftype, cifs_sb);
 	if (rc) {
 		/*
@@ -3189,11 +3213,23 @@ handle_read_data(struct TCP_Server_Info *server, struct mid_q_entry *mid,
 			server->ops->is_status_pending(buf, server, 0))
 		return -1;
 
-	rdata->result = server->ops->map_error(buf, false);
+	/* set up first two iov to get credits */
+	rdata->iov[0].iov_base = buf;
+	rdata->iov[0].iov_len = 4;
+	rdata->iov[1].iov_base = buf + 4;
+	rdata->iov[1].iov_len =
+		min_t(unsigned int, buf_len, server->vals->read_rsp_size) - 4;
+	cifs_dbg(FYI, "0: iov_base=%p iov_len=%zu\n",
+		 rdata->iov[0].iov_base, rdata->iov[0].iov_len);
+	cifs_dbg(FYI, "1: iov_base=%p iov_len=%zu\n",
+		 rdata->iov[1].iov_base, rdata->iov[1].iov_len);
+
+	rdata->result = server->ops->map_error(buf, true);
 	if (rdata->result != 0) {
 		cifs_dbg(FYI, "%s: server returned error %d\n",
 			 __func__, rdata->result);
-		dequeue_mid(mid, rdata->result);
+		/* normal error on read response */
+		dequeue_mid(mid, false);
 		return 0;
 	}
 
@@ -3266,14 +3302,6 @@ handle_read_data(struct TCP_Server_Info *server, struct mid_q_entry *mid,
 		return 0;
 	}
 
-	/* set up first iov for signature check */
-	rdata->iov[0].iov_base = buf;
-	rdata->iov[0].iov_len = 4;
-	rdata->iov[1].iov_base = buf + 4;
-	rdata->iov[1].iov_len = server->vals->read_rsp_size - 4;
-	cifs_dbg(FYI, "0: iov_base=%p iov_len=%zu\n",
-		 rdata->iov[0].iov_base, server->vals->read_rsp_size);
-
 	length = rdata->copy_into_pages(server, rdata, &iter);
 
 	kfree(bvec);
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 50811a7dc0e0..77b3aaa39b35 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -2816,6 +2816,7 @@ query_info(const unsigned int xid, struct cifs_tcon *tcon,
 	int resp_buftype = CIFS_NO_BUFFER;
 	struct cifs_ses *ses = tcon->ses;
 	int flags = 0;
+	bool allocated = false;
 
 	cifs_dbg(FYI, "Query Info\n");
 
@@ -2855,14 +2856,21 @@ query_info(const unsigned int xid, struct cifs_tcon *tcon,
 					"Error %d allocating memory for acl\n",
 					rc);
 				*dlen = 0;
+				rc = -ENOMEM;
 				goto qinf_exit;
 			}
+			allocated = true;
 		}
 	}
 
 	rc = smb2_validate_and_copy_iov(le16_to_cpu(rsp->OutputBufferOffset),
 					le32_to_cpu(rsp->OutputBufferLength),
 					&rsp_iov, min_len, *data);
+	if (rc && allocated) {
+		kfree(*data);
+		*data = NULL;
+		*dlen = 0;
+	}
 
 qinf_exit:
 	SMB2_query_info_free(&rqst);
@@ -2916,9 +2924,10 @@ smb2_echo_callback(struct mid_q_entry *mid)
 {
 	struct TCP_Server_Info *server = mid->callback_data;
 	struct smb2_echo_rsp *rsp = (struct smb2_echo_rsp *)mid->resp_buf;
-	unsigned int credits_received = 1;
+	unsigned int credits_received = 0;
 
-	if (mid->mid_state == MID_RESPONSE_RECEIVED)
+	if (mid->mid_state == MID_RESPONSE_RECEIVED
+	    || mid->mid_state == MID_RESPONSE_MALFORMED)
 		credits_received = le16_to_cpu(rsp->sync_hdr.CreditRequest);
 
 	DeleteMidQEntry(mid);
@@ -3175,7 +3184,7 @@ smb2_readv_callback(struct mid_q_entry *mid)
 	struct TCP_Server_Info *server = tcon->ses->server;
 	struct smb2_sync_hdr *shdr =
 				(struct smb2_sync_hdr *)rdata->iov[0].iov_base;
-	unsigned int credits_received = 1;
+	unsigned int credits_received = 0;
 	struct smb_rqst rqst = { .rq_iov = rdata->iov,
 				 .rq_nvec = 2,
 				 .rq_pages = rdata->pages,
@@ -3214,6 +3223,9 @@ smb2_readv_callback(struct mid_q_entry *mid)
 		task_io_account_read(rdata->got_bytes);
 		cifs_stats_bytes_read(tcon, rdata->got_bytes);
 		break;
+	case MID_RESPONSE_MALFORMED:
+		credits_received = le16_to_cpu(shdr->CreditRequest);
+		/* fall through */
 	default:
 		if (rdata->result != -ENODATA)
 			rdata->result = -EIO;
@@ -3229,8 +3241,17 @@ smb2_readv_callback(struct mid_q_entry *mid)
 		rdata->mr = NULL;
 	}
 #endif
-	if (rdata->result)
+	if (rdata->result && rdata->result != -ENODATA) {
 		cifs_stats_fail_inc(tcon, SMB2_READ_HE);
+		trace_smb3_read_err(0 /* xid */,
+				    rdata->cfile->fid.persistent_fid,
+				    tcon->tid, tcon->ses->Suid, rdata->offset,
+				    rdata->bytes, rdata->result);
+	} else
+		trace_smb3_read_done(0 /* xid */,
+				     rdata->cfile->fid.persistent_fid,
+				     tcon->tid, tcon->ses->Suid,
+				     rdata->offset, rdata->got_bytes);
 
 	queue_work(cifsiod_wq, &rdata->work);
 	DeleteMidQEntry(mid);
@@ -3305,13 +3326,11 @@ smb2_async_readv(struct cifs_readdata *rdata)
 	if (rc) {
 		kref_put(&rdata->refcount, cifs_readdata_release);
 		cifs_stats_fail_inc(io_parms.tcon, SMB2_READ_HE);
-		trace_smb3_read_err(rc, 0 /* xid */, io_parms.persistent_fid,
-				   io_parms.tcon->tid, io_parms.tcon->ses->Suid,
-				   io_parms.offset, io_parms.length);
-	} else
-		trace_smb3_read_done(0 /* xid */, io_parms.persistent_fid,
-				   io_parms.tcon->tid, io_parms.tcon->ses->Suid,
-				   io_parms.offset, io_parms.length);
+		trace_smb3_read_err(0 /* xid */, io_parms.persistent_fid,
+				    io_parms.tcon->tid,
+				    io_parms.tcon->ses->Suid,
+				    io_parms.offset, io_parms.length, rc);
+	}
 
 	cifs_small_buf_release(buf);
 	return rc;
@@ -3355,10 +3374,11 @@ SMB2_read(const unsigned int xid, struct cifs_io_parms *io_parms,
 		if (rc != -ENODATA) {
 			cifs_stats_fail_inc(io_parms->tcon, SMB2_READ_HE);
 			cifs_dbg(VFS, "Send error in read = %d\n", rc);
+			trace_smb3_read_err(xid, req->PersistentFileId,
+					    io_parms->tcon->tid, ses->Suid,
+					    io_parms->offset, io_parms->length,
+					    rc);
 		}
-		trace_smb3_read_err(rc, xid, req->PersistentFileId,
-				    io_parms->tcon->tid, ses->Suid,
-				    io_parms->offset, io_parms->length);
 		free_rsp_buf(resp_buftype, rsp_iov.iov_base);
 		return rc == -ENODATA ? 0 : rc;
 	} else
@@ -3399,7 +3419,7 @@ smb2_writev_callback(struct mid_q_entry *mid)
 	struct cifs_tcon *tcon = tlink_tcon(wdata->cfile->tlink);
 	unsigned int written;
 	struct smb2_write_rsp *rsp = (struct smb2_write_rsp *)mid->resp_buf;
-	unsigned int credits_received = 1;
+	unsigned int credits_received = 0;
 
 	switch (mid->mid_state) {
 	case MID_RESPONSE_RECEIVED:
@@ -3427,6 +3447,9 @@ smb2_writev_callback(struct mid_q_entry *mid)
 	case MID_RETRY_NEEDED:
 		wdata->result = -EAGAIN;
 		break;
+	case MID_RESPONSE_MALFORMED:
+		credits_received = le16_to_cpu(rsp->sync_hdr.CreditRequest);
+		/* fall through */
 	default:
 		wdata->result = -EIO;
 		break;
@@ -3444,8 +3467,17 @@ smb2_writev_callback(struct mid_q_entry *mid)
 		wdata->mr = NULL;
 	}
 #endif
-	if (wdata->result)
+	if (wdata->result) {
 		cifs_stats_fail_inc(tcon, SMB2_WRITE_HE);
+		trace_smb3_write_err(0 /* no xid */,
+				     wdata->cfile->fid.persistent_fid,
+				     tcon->tid, tcon->ses->Suid, wdata->offset,
+				     wdata->bytes, wdata->result);
+	} else
+		trace_smb3_write_done(0 /* no xid */,
+				      wdata->cfile->fid.persistent_fid,
+				      tcon->tid, tcon->ses->Suid,
+				      wdata->offset, wdata->bytes);
 
 	queue_work(cifsiod_wq, &wdata->work);
 	DeleteMidQEntry(mid);
@@ -3587,10 +3619,7 @@ smb2_async_writev(struct cifs_writedata *wdata,
 				     wdata->bytes, rc);
 		kref_put(&wdata->refcount, release);
 		cifs_stats_fail_inc(tcon, SMB2_WRITE_HE);
-	} else
-		trace_smb3_write_done(0 /* no xid */, req->PersistentFileId,
-				     tcon->tid, tcon->ses->Suid, wdata->offset,
-				     wdata->bytes);
+	}
 
 async_writev_out:
 	cifs_small_buf_release(req);
@@ -3816,8 +3845,8 @@ SMB2_query_directory(const unsigned int xid, struct cifs_tcon *tcon,
 		    rsp->sync_hdr.Status == STATUS_NO_MORE_FILES) {
 			srch_inf->endOfSearch = true;
 			rc = 0;
-		}
-		cifs_stats_fail_inc(tcon, SMB2_QUERY_DIRECTORY_HE);
+		} else
+			cifs_stats_fail_inc(tcon, SMB2_QUERY_DIRECTORY_HE);
 		goto qdir_exit;
 	}
 
@@ -4412,8 +4441,8 @@ SMB2_lease_break(const unsigned int xid, struct cifs_tcon *tcon,
 	rc = cifs_send_recv(xid, ses, &rqst, &resp_buf_type, flags, &rsp_iov);
 	cifs_small_buf_release(req);
 
-	please_key_low = (__u64 *)req->LeaseKey;
-	please_key_high = (__u64 *)(req->LeaseKey+8);
+	please_key_low = (__u64 *)lease_key;
+	please_key_high = (__u64 *)(lease_key+8);
 	if (rc) {
 		cifs_stats_fail_inc(tcon, SMB2_OPLOCK_BREAK_HE);
 		trace_smb3_lease_err(le32_to_cpu(lease_state), tcon->tid,
diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h
index 7a2d0a2255e6..538e2299805f 100644
--- a/fs/cifs/smb2pdu.h
+++ b/fs/cifs/smb2pdu.h
@@ -84,8 +84,9 @@
 
 #define NUMBER_OF_SMB2_COMMANDS	0x0013
 
-/* 4 len + 52 transform hdr + 64 hdr + 56 create rsp */
-#define MAX_SMB2_HDR_SIZE 0x00b0
+/* 52 transform hdr + 64 hdr + 88 create rsp */
+#define SMB2_TRANSFORM_HEADER_SIZE 52
+#define MAX_SMB2_HDR_SIZE 204
 
 #define SMB2_PROTO_NUMBER cpu_to_le32(0x424d53fe)
 #define SMB2_TRANSFORM_PROTO_NUM cpu_to_le32(0x424d53fd)
@@ -648,6 +649,13 @@ struct smb2_create_req {
 	__u8   Buffer[0];
 } __packed;
 
+/*
+ * Maximum size of a SMB2_CREATE response is 64 (smb2 header) +
+ * 88 (fixed part of create response) + 520 (path) + 150 (contexts) +
+ * 2 bytes of padding.
+ */
+#define MAX_SMB2_CREATE_RESPONSE_SIZE 824
+
 struct smb2_create_rsp {
 	struct smb2_sync_hdr sync_hdr;
 	__le16 StructureSize;	/* Must be 89 */
@@ -996,6 +1004,11 @@ struct smb2_close_req {
 	__u64  VolatileFileId; /* opaque endianness */
 } __packed;
 
+/*
+ * Maximum size of a SMB2_CLOSE response is 64 (smb2 header) + 60 (data)
+ */
+#define MAX_SMB2_CLOSE_RESPONSE_SIZE 124
+
 struct smb2_close_rsp {
 	struct smb2_sync_hdr sync_hdr;
 	__le16 StructureSize; /* 60 */
@@ -1398,8 +1411,6 @@ struct smb2_file_link_info { /* encoding of request for level 11 */
 	char   FileName[0];     /* Name to be assigned to new link */
 } __packed; /* level 11 Set */
 
-#define SMB2_MAX_EA_BUF 65536
-
 struct smb2_file_full_ea_info { /* encoding of response for level 15 */
 	__le32 next_entry_offset;
 	__u8   flags;
diff --git a/fs/cifs/trace.c b/fs/cifs/trace.c
index bd4a546feec1..465483787193 100644
--- a/fs/cifs/trace.c
+++ b/fs/cifs/trace.c
@@ -3,16 +3,6 @@
  *   Copyright (C) 2018, Microsoft Corporation.
  *
  *   Author(s): Steve French <stfrench@microsoft.com>
- *
- *   This program is free software;  you can redistribute it and/or modify
- *   it under the terms of the GNU General Public License as published by
- *   the Free Software Foundation; either version 2 of the License, or
- *   (at your option) any later version.
- *
- *   This program is distributed in the hope that it will be useful,
- *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
- *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
- *   the GNU General Public License for more details.
  */
 #define CREATE_TRACE_POINTS
 #include "trace.h"
diff --git a/fs/cifs/trace.h b/fs/cifs/trace.h
index fb049809555f..59be48206932 100644
--- a/fs/cifs/trace.h
+++ b/fs/cifs/trace.h
@@ -3,16 +3,6 @@
  *   Copyright (C) 2018, Microsoft Corporation.
  *
  *   Author(s): Steve French <stfrench@microsoft.com>
- *
- *   This program is free software;  you can redistribute it and/or modify
- *   it under the terms of the GNU General Public License as published by
- *   the Free Software Foundation; either version 2 of the License, or
- *   (at your option) any later version.
- *
- *   This program is distributed in the hope that it will be useful,
- *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
- *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
- *   the GNU General Public License for more details.
  */
 #undef TRACE_SYSTEM
 #define TRACE_SYSTEM cifs
diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
index 202e0e84efdd..53532bd3f50d 100644
--- a/fs/cifs/transport.c
+++ b/fs/cifs/transport.c
@@ -786,17 +786,8 @@ static void
 cifs_compound_callback(struct mid_q_entry *mid)
 {
 	struct TCP_Server_Info *server = mid->server;
-	unsigned int optype = mid->optype;
-	unsigned int credits_received = 0;
 
-	if (mid->mid_state == MID_RESPONSE_RECEIVED) {
-		if (mid->resp_buf)
-			credits_received = server->ops->get_credits(mid);
-		else
-			cifs_dbg(FYI, "Bad state for cancelled MID\n");
-	}
-
-	add_credits(server, credits_received, optype);
+	add_credits(server, server->ops->get_credits(mid), mid->optype);
 }
 
 static void
diff --git a/fs/dcache.c b/fs/dcache.c
index 2593153471cf..aac41adf4743 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -119,6 +119,7 @@ struct dentry_stat_t dentry_stat = {
 
 static DEFINE_PER_CPU(long, nr_dentry);
 static DEFINE_PER_CPU(long, nr_dentry_unused);
+static DEFINE_PER_CPU(long, nr_dentry_negative);
 
 #if defined(CONFIG_SYSCTL) && defined(CONFIG_PROC_FS)
 
@@ -152,11 +153,22 @@ static long get_nr_dentry_unused(void)
 	return sum < 0 ? 0 : sum;
 }
 
+static long get_nr_dentry_negative(void)
+{
+	int i;
+	long sum = 0;
+
+	for_each_possible_cpu(i)
+		sum += per_cpu(nr_dentry_negative, i);
+	return sum < 0 ? 0 : sum;
+}
+
 int proc_nr_dentry(struct ctl_table *table, int write, void __user *buffer,
 		   size_t *lenp, loff_t *ppos)
 {
 	dentry_stat.nr_dentry = get_nr_dentry();
 	dentry_stat.nr_unused = get_nr_dentry_unused();
+	dentry_stat.nr_negative = get_nr_dentry_negative();
 	return proc_doulongvec_minmax(table, write, buffer, lenp, ppos);
 }
 #endif
@@ -317,6 +329,8 @@ static inline void __d_clear_type_and_inode(struct dentry *dentry)
 	flags &= ~(DCACHE_ENTRY_TYPE | DCACHE_FALLTHRU);
 	WRITE_ONCE(dentry->d_flags, flags);
 	dentry->d_inode = NULL;
+	if (dentry->d_flags & DCACHE_LRU_LIST)
+		this_cpu_inc(nr_dentry_negative);
 }
 
 static void dentry_free(struct dentry *dentry)
@@ -371,6 +385,11 @@ static void dentry_unlink_inode(struct dentry * dentry)
  * The per-cpu "nr_dentry_unused" counters are updated with
  * the DCACHE_LRU_LIST bit.
  *
+ * The per-cpu "nr_dentry_negative" counters are only updated
+ * when deleted from or added to the per-superblock LRU list, not
+ * from/to the shrink list. That is to avoid an unneeded dec/inc
+ * pair when moving from LRU to shrink list in select_collect().
+ *
  * These helper functions make sure we always follow the
  * rules. d_lock must be held by the caller.
  */
@@ -380,6 +399,8 @@ static void d_lru_add(struct dentry *dentry)
 	D_FLAG_VERIFY(dentry, 0);
 	dentry->d_flags |= DCACHE_LRU_LIST;
 	this_cpu_inc(nr_dentry_unused);
+	if (d_is_negative(dentry))
+		this_cpu_inc(nr_dentry_negative);
 	WARN_ON_ONCE(!list_lru_add(&dentry->d_sb->s_dentry_lru, &dentry->d_lru));
 }
 
@@ -388,6 +409,8 @@ static void d_lru_del(struct dentry *dentry)
 	D_FLAG_VERIFY(dentry, DCACHE_LRU_LIST);
 	dentry->d_flags &= ~DCACHE_LRU_LIST;
 	this_cpu_dec(nr_dentry_unused);
+	if (d_is_negative(dentry))
+		this_cpu_dec(nr_dentry_negative);
 	WARN_ON_ONCE(!list_lru_del(&dentry->d_sb->s_dentry_lru, &dentry->d_lru));
 }
 
@@ -418,6 +441,8 @@ static void d_lru_isolate(struct list_lru_one *lru, struct dentry *dentry)
 	D_FLAG_VERIFY(dentry, DCACHE_LRU_LIST);
 	dentry->d_flags &= ~DCACHE_LRU_LIST;
 	this_cpu_dec(nr_dentry_unused);
+	if (d_is_negative(dentry))
+		this_cpu_dec(nr_dentry_negative);
 	list_lru_isolate(lru, &dentry->d_lru);
 }
 
@@ -426,6 +451,8 @@ static void d_lru_shrink_move(struct list_lru_one *lru, struct dentry *dentry,
 {
 	D_FLAG_VERIFY(dentry, DCACHE_LRU_LIST);
 	dentry->d_flags |= DCACHE_SHRINK_LIST;
+	if (d_is_negative(dentry))
+		this_cpu_dec(nr_dentry_negative);
 	list_lru_isolate_move(lru, &dentry->d_lru, list);
 }
 
@@ -1188,15 +1215,11 @@ static enum lru_status dentry_lru_isolate_shrink(struct list_head *item,
  */
 void shrink_dcache_sb(struct super_block *sb)
 {
-	long freed;
-
 	do {
 		LIST_HEAD(dispose);
 
-		freed = list_lru_walk(&sb->s_dentry_lru,
+		list_lru_walk(&sb->s_dentry_lru,
 			dentry_lru_isolate_shrink, &dispose, 1024);
-
-		this_cpu_sub(nr_dentry_unused, freed);
 		shrink_dentry_list(&dispose);
 	} while (list_lru_count(&sb->s_dentry_lru) > 0);
 }
@@ -1820,6 +1843,11 @@ static void __d_instantiate(struct dentry *dentry, struct inode *inode)
 	WARN_ON(d_in_lookup(dentry));
 
 	spin_lock(&dentry->d_lock);
+	/*
+	 * Decrement negative dentry count if it was in the LRU list.
+	 */
+	if (dentry->d_flags & DCACHE_LRU_LIST)
+		this_cpu_dec(nr_dentry_negative);
 	hlist_add_head(&dentry->d_u.d_alias, &inode->i_dentry);
 	raw_write_seqcount_begin(&dentry->d_seq);
 	__d_set_inode_and_type(dentry, inode, add_flags);
diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
index 13b01351dd1c..29c68c5d44d5 100644
--- a/fs/debugfs/inode.c
+++ b/fs/debugfs/inode.c
@@ -324,7 +324,7 @@ static struct dentry *failed_creating(struct dentry *dentry)
 	inode_unlock(d_inode(dentry->d_parent));
 	dput(dentry);
 	simple_release_fs(&debugfs_mount, &debugfs_mount_count);
-	return NULL;
+	return ERR_PTR(-ENOMEM);
 }
 
 static struct dentry *end_creating(struct dentry *dentry)
@@ -347,7 +347,7 @@ static struct dentry *__debugfs_create_file(const char *name, umode_t mode,
 	dentry = start_creating(name, parent);
 
 	if (IS_ERR(dentry))
-		return NULL;
+		return dentry;
 
 	inode = debugfs_get_inode(dentry->d_sb);
 	if (unlikely(!inode))
@@ -386,7 +386,8 @@ static struct dentry *__debugfs_create_file(const char *name, umode_t mode,
  * This function will return a pointer to a dentry if it succeeds.  This
  * pointer must be passed to the debugfs_remove() function when the file is
  * to be removed (no automatic cleanup happens if your module is unloaded,
- * you are responsible here.)  If an error occurs, %NULL will be returned.
+ * you are responsible here.)  If an error occurs, %ERR_PTR(-ERROR) will be
+ * returned.
  *
  * If debugfs is not enabled in the kernel, the value -%ENODEV will be
  * returned.
@@ -464,7 +465,8 @@ EXPORT_SYMBOL_GPL(debugfs_create_file_unsafe);
  * This function will return a pointer to a dentry if it succeeds.  This
  * pointer must be passed to the debugfs_remove() function when the file is
  * to be removed (no automatic cleanup happens if your module is unloaded,
- * you are responsible here.)  If an error occurs, %NULL will be returned.
+ * you are responsible here.)  If an error occurs, %ERR_PTR(-ERROR) will be
+ * returned.
  *
  * If debugfs is not enabled in the kernel, the value -%ENODEV will be
  * returned.
@@ -495,7 +497,8 @@ EXPORT_SYMBOL_GPL(debugfs_create_file_size);
  * This function will return a pointer to a dentry if it succeeds.  This
  * pointer must be passed to the debugfs_remove() function when the file is
  * to be removed (no automatic cleanup happens if your module is unloaded,
- * you are responsible here.)  If an error occurs, %NULL will be returned.
+ * you are responsible here.)  If an error occurs, %ERR_PTR(-ERROR) will be
+ * returned.
  *
  * If debugfs is not enabled in the kernel, the value -%ENODEV will be
  * returned.
@@ -506,7 +509,7 @@ struct dentry *debugfs_create_dir(const char *name, struct dentry *parent)
 	struct inode *inode;
 
 	if (IS_ERR(dentry))
-		return NULL;
+		return dentry;
 
 	inode = debugfs_get_inode(dentry->d_sb);
 	if (unlikely(!inode))
@@ -545,7 +548,7 @@ struct dentry *debugfs_create_automount(const char *name,
 	struct inode *inode;
 
 	if (IS_ERR(dentry))
-		return NULL;
+		return dentry;
 
 	inode = debugfs_get_inode(dentry->d_sb);
 	if (unlikely(!inode))
@@ -581,8 +584,8 @@ EXPORT_SYMBOL(debugfs_create_automount);
  * This function will return a pointer to a dentry if it succeeds.  This
  * pointer must be passed to the debugfs_remove() function when the symbolic
  * link is to be removed (no automatic cleanup happens if your module is
- * unloaded, you are responsible here.)  If an error occurs, %NULL will be
- * returned.
+ * unloaded, you are responsible here.)  If an error occurs, %ERR_PTR(-ERROR)
+ * will be returned.
  *
  * If debugfs is not enabled in the kernel, the value -%ENODEV will be
  * returned.
@@ -594,12 +597,12 @@ struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent,
 	struct inode *inode;
 	char *link = kstrdup(target, GFP_KERNEL);
 	if (!link)
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 
 	dentry = start_creating(name, parent);
 	if (IS_ERR(dentry)) {
 		kfree(link);
-		return NULL;
+		return dentry;
 	}
 
 	inode = debugfs_get_inode(dentry->d_sb);
@@ -787,6 +790,13 @@ struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
 	struct dentry *dentry = NULL, *trap;
 	struct name_snapshot old_name;
 
+	if (IS_ERR(old_dir))
+		return old_dir;
+	if (IS_ERR(new_dir))
+		return new_dir;
+	if (IS_ERR_OR_NULL(old_dentry))
+		return old_dentry;
+
 	trap = lock_rename(new_dir, old_dir);
 	/* Source or destination directories don't exist? */
 	if (d_really_is_negative(old_dir) || d_really_is_negative(new_dir))
@@ -820,7 +830,9 @@ exit:
 	if (dentry && !IS_ERR(dentry))
 		dput(dentry);
 	unlock_rename(new_dir, old_dir);
-	return NULL;
+	if (IS_ERR(dentry))
+		return dentry;
+	return ERR_PTR(-EINVAL);
 }
 EXPORT_SYMBOL_GPL(debugfs_rename);
 
diff --git a/fs/direct-io.c b/fs/direct-io.c
index dbc1a1f080ce..ec2fb6fe6d37 100644
--- a/fs/direct-io.c
+++ b/fs/direct-io.c
@@ -679,6 +679,7 @@ static int get_more_blocks(struct dio *dio, struct dio_submit *sdio,
 	unsigned long fs_count;	/* Number of filesystem-sized blocks */
 	int create;
 	unsigned int i_blkbits = sdio->blkbits + sdio->blkfactor;
+	loff_t i_size;
 
 	/*
 	 * If there was a memory error and we've overwritten all the
@@ -708,8 +709,8 @@ static int get_more_blocks(struct dio *dio, struct dio_submit *sdio,
 		 */
 		create = dio->op == REQ_OP_WRITE;
 		if (dio->flags & DIO_SKIP_HOLES) {
-			if (fs_startblk <= ((i_size_read(dio->inode) - 1) >>
-							i_blkbits))
+			i_size = i_size_read(dio->inode);
+			if (i_size && fs_startblk <= (i_size - 1) >> i_blkbits)
 				create = 0;
 		}
 
diff --git a/fs/drop_caches.c b/fs/drop_caches.c
index 82377017130f..d31b6c72b476 100644
--- a/fs/drop_caches.c
+++ b/fs/drop_caches.c
@@ -21,8 +21,13 @@ static void drop_pagecache_sb(struct super_block *sb, void *unused)
 	spin_lock(&sb->s_inode_list_lock);
 	list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
 		spin_lock(&inode->i_lock);
+		/*
+		 * We must skip inodes in unusual state. We may also skip
+		 * inodes without pages but we deliberately won't in case
+		 * we need to reschedule to avoid softlockups.
+		 */
 		if ((inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) ||
-		    (inode->i_mapping->nrpages == 0)) {
+		    (inode->i_mapping->nrpages == 0 && !need_resched())) {
 			spin_unlock(&inode->i_lock);
 			continue;
 		}
@@ -30,6 +35,7 @@ static void drop_pagecache_sb(struct super_block *sb, void *unused)
 		spin_unlock(&inode->i_lock);
 		spin_unlock(&sb->s_inode_list_lock);
 
+		cond_resched();
 		invalidate_mapping_pages(inode->i_mapping, 0, -1);
 		iput(toput_inode);
 		toput_inode = inode;
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index b40168fcc94a..36855c1f8daf 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -331,11 +331,22 @@ struct inode_switch_wbs_context {
 	struct work_struct	work;
 };
 
+static void bdi_down_write_wb_switch_rwsem(struct backing_dev_info *bdi)
+{
+	down_write(&bdi->wb_switch_rwsem);
+}
+
+static void bdi_up_write_wb_switch_rwsem(struct backing_dev_info *bdi)
+{
+	up_write(&bdi->wb_switch_rwsem);
+}
+
 static void inode_switch_wbs_work_fn(struct work_struct *work)
 {
 	struct inode_switch_wbs_context *isw =
 		container_of(work, struct inode_switch_wbs_context, work);
 	struct inode *inode = isw->inode;
+	struct backing_dev_info *bdi = inode_to_bdi(inode);
 	struct address_space *mapping = inode->i_mapping;
 	struct bdi_writeback *old_wb = inode->i_wb;
 	struct bdi_writeback *new_wb = isw->new_wb;
@@ -344,6 +355,12 @@ static void inode_switch_wbs_work_fn(struct work_struct *work)
 	bool switched = false;
 
 	/*
+	 * If @inode switches cgwb membership while sync_inodes_sb() is
+	 * being issued, sync_inodes_sb() might miss it.  Synchronize.
+	 */
+	down_read(&bdi->wb_switch_rwsem);
+
+	/*
 	 * By the time control reaches here, RCU grace period has passed
 	 * since I_WB_SWITCH assertion and all wb stat update transactions
 	 * between unlocked_inode_to_wb_begin/end() are guaranteed to be
@@ -428,6 +445,8 @@ skip_switch:
 	spin_unlock(&new_wb->list_lock);
 	spin_unlock(&old_wb->list_lock);
 
+	up_read(&bdi->wb_switch_rwsem);
+
 	if (switched) {
 		wb_wakeup(new_wb);
 		wb_put(old_wb);
@@ -468,9 +487,18 @@ static void inode_switch_wbs(struct inode *inode, int new_wb_id)
 	if (inode->i_state & I_WB_SWITCH)
 		return;
 
+	/*
+	 * Avoid starting new switches while sync_inodes_sb() is in
+	 * progress.  Otherwise, if the down_write protected issue path
+	 * blocks heavily, we might end up starting a large number of
+	 * switches which will block on the rwsem.
+	 */
+	if (!down_read_trylock(&bdi->wb_switch_rwsem))
+		return;
+
 	isw = kzalloc(sizeof(*isw), GFP_ATOMIC);
 	if (!isw)
-		return;
+		goto out_unlock;
 
 	/* find and pin the new wb */
 	rcu_read_lock();
@@ -504,12 +532,14 @@ static void inode_switch_wbs(struct inode *inode, int new_wb_id)
 	 * Let's continue after I_WB_SWITCH is guaranteed to be visible.
 	 */
 	call_rcu(&isw->rcu_head, inode_switch_wbs_rcu_fn);
-	return;
+	goto out_unlock;
 
 out_free:
 	if (isw->new_wb)
 		wb_put(isw->new_wb);
 	kfree(isw);
+out_unlock:
+	up_read(&bdi->wb_switch_rwsem);
 }
 
 /**
@@ -887,6 +917,9 @@ fs_initcall(cgroup_writeback_init);
 
 #else	/* CONFIG_CGROUP_WRITEBACK */
 
+static void bdi_down_write_wb_switch_rwsem(struct backing_dev_info *bdi) { }
+static void bdi_up_write_wb_switch_rwsem(struct backing_dev_info *bdi) { }
+
 static struct bdi_writeback *
 locked_inode_to_wb_and_lock_list(struct inode *inode)
 	__releases(&inode->i_lock)
@@ -2413,8 +2446,11 @@ void sync_inodes_sb(struct super_block *sb)
 		return;
 	WARN_ON(!rwsem_is_locked(&sb->s_umount));
 
+	/* protect against inode wb switch, see inode_switch_wbs_work_fn() */
+	bdi_down_write_wb_switch_rwsem(bdi);
 	bdi_split_work_to_wbs(bdi, &work, false);
 	wb_wait_for_completion(bdi, &done);
+	bdi_up_write_wb_switch_rwsem(bdi);
 
 	wait_sb_inodes(sb);
 }
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index a5e516a40e7a..809c0f2f9942 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -1742,7 +1742,6 @@ static int fuse_retrieve(struct fuse_conn *fc, struct inode *inode,
 	req->in.h.nodeid = outarg->nodeid;
 	req->in.numargs = 2;
 	req->in.argpages = 1;
-	req->page_descs[0].offset = offset;
 	req->end = fuse_retrieve_end;
 
 	index = outarg->offset >> PAGE_SHIFT;
@@ -1757,6 +1756,7 @@ static int fuse_retrieve(struct fuse_conn *fc, struct inode *inode,
 
 		this_num = min_t(unsigned, num, PAGE_SIZE - offset);
 		req->pages[req->num_pages] = page;
+		req->page_descs[req->num_pages].offset = offset;
 		req->page_descs[req->num_pages].length = this_num;
 		req->num_pages++;
 
@@ -2077,8 +2077,10 @@ static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe,
 
 	ret = fuse_dev_do_write(fud, &cs, len);
 
+	pipe_lock(pipe);
 	for (idx = 0; idx < nbuf; idx++)
 		pipe_buf_release(pipe, &bufs[idx]);
+	pipe_unlock(pipe);
 
 out:
 	kvfree(bufs);
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index ffaffe18352a..a59c16bd90ac 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -1782,7 +1782,7 @@ static bool fuse_writepage_in_flight(struct fuse_req *new_req,
 		spin_unlock(&fc->lock);
 
 		dec_wb_stat(&bdi->wb, WB_WRITEBACK);
-		dec_node_page_state(page, NR_WRITEBACK_TEMP);
+		dec_node_page_state(new_req->pages[0], NR_WRITEBACK_TEMP);
 		wb_writeout_inc(&bdi->wb);
 		fuse_writepage_free(fc, new_req);
 		fuse_request_free(new_req);
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index 76baaa6be393..c2d4099429be 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -628,6 +628,7 @@ void fuse_conn_init(struct fuse_conn *fc, struct user_namespace *user_ns)
 	get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key));
 	fc->pid_ns = get_pid_ns(task_active_pid_ns(current));
 	fc->user_ns = get_user_ns(user_ns);
+	fc->max_pages = FUSE_DEFAULT_MAX_PAGES_PER_REQ;
 }
 EXPORT_SYMBOL_GPL(fuse_conn_init);
 
@@ -1162,7 +1163,6 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent)
 	fc->user_id = d.user_id;
 	fc->group_id = d.group_id;
 	fc->max_read = max_t(unsigned, 4096, d.max_read);
-	fc->max_pages = FUSE_DEFAULT_MAX_PAGES_PER_REQ;
 
 	/* Used by get_root_inode() */
 	sb->s_fs_info = fc;
diff --git a/fs/gfs2/rgrp.c b/fs/gfs2/rgrp.c
index 831d7cb5a49c..17a8d3b43990 100644
--- a/fs/gfs2/rgrp.c
+++ b/fs/gfs2/rgrp.c
@@ -1780,9 +1780,9 @@ static int gfs2_rbm_find(struct gfs2_rbm *rbm, u8 state, u32 *minext,
 			goto next_iter;
 		}
 		if (ret == -E2BIG) {
-			n += rbm->bii - initial_bii;
 			rbm->bii = 0;
 			rbm->offset = 0;
+			n += (rbm->bii - initial_bii);
 			goto res_covered_end_of_rgrp;
 		}
 		return ret;
diff --git a/fs/iomap.c b/fs/iomap.c
index a3088fae567b..897c60215dd1 100644
--- a/fs/iomap.c
+++ b/fs/iomap.c
@@ -116,6 +116,12 @@ iomap_page_create(struct inode *inode, struct page *page)
 	atomic_set(&iop->read_count, 0);
 	atomic_set(&iop->write_count, 0);
 	bitmap_zero(iop->uptodate, PAGE_SIZE / SECTOR_SIZE);
+
+	/*
+	 * migrate_page_move_mapping() assumes that pages with private data have
+	 * their count elevated by 1.
+	 */
+	get_page(page);
 	set_page_private(page, (unsigned long)iop);
 	SetPagePrivate(page);
 	return iop;
@@ -132,6 +138,7 @@ iomap_page_release(struct page *page)
 	WARN_ON_ONCE(atomic_read(&iop->write_count));
 	ClearPagePrivate(page);
 	set_page_private(page, 0);
+	put_page(page);
 	kfree(iop);
 }
 
@@ -569,8 +576,10 @@ iomap_migrate_page(struct address_space *mapping, struct page *newpage,
 
 	if (page_has_private(page)) {
 		ClearPagePrivate(page);
+		get_page(newpage);
 		set_page_private(newpage, page_private(page));
 		set_page_private(page, 0);
+		put_page(page);
 		SetPagePrivate(newpage);
 	}
 
@@ -1804,6 +1813,7 @@ iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter,
 	loff_t pos = iocb->ki_pos, start = pos;
 	loff_t end = iocb->ki_pos + count - 1, ret = 0;
 	unsigned int flags = IOMAP_DIRECT;
+	bool wait_for_completion = is_sync_kiocb(iocb);
 	struct blk_plug plug;
 	struct iomap_dio *dio;
 
@@ -1823,7 +1833,6 @@ iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter,
 	dio->end_io = end_io;
 	dio->error = 0;
 	dio->flags = 0;
-	dio->wait_for_completion = is_sync_kiocb(iocb);
 
 	dio->submit.iter = iter;
 	dio->submit.waiter = current;
@@ -1878,7 +1887,7 @@ iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter,
 		dio_warn_stale_pagecache(iocb->ki_filp);
 	ret = 0;
 
-	if (iov_iter_rw(iter) == WRITE && !dio->wait_for_completion &&
+	if (iov_iter_rw(iter) == WRITE && !wait_for_completion &&
 	    !inode->i_sb->s_dio_done_wq) {
 		ret = sb_init_dio_done_wq(inode->i_sb);
 		if (ret < 0)
@@ -1894,7 +1903,7 @@ iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter,
 		if (ret <= 0) {
 			/* magic error code to fall back to buffered I/O */
 			if (ret == -ENOTBLK) {
-				dio->wait_for_completion = true;
+				wait_for_completion = true;
 				ret = 0;
 			}
 			break;
@@ -1916,8 +1925,24 @@ iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter,
 	if (dio->flags & IOMAP_DIO_WRITE_FUA)
 		dio->flags &= ~IOMAP_DIO_NEED_SYNC;
 
+	/*
+	 * We are about to drop our additional submission reference, which
+	 * might be the last reference to the dio.  There are three three
+	 * different ways we can progress here:
+	 *
+	 *  (a) If this is the last reference we will always complete and free
+	 *	the dio ourselves.
+	 *  (b) If this is not the last reference, and we serve an asynchronous
+	 *	iocb, we must never touch the dio after the decrement, the
+	 *	I/O completion handler will complete and free it.
+	 *  (c) If this is not the last reference, but we serve a synchronous
+	 *	iocb, the I/O completion handler will wake us up on the drop
+	 *	of the final reference, and we will complete and free it here
+	 *	after we got woken by the I/O completion handler.
+	 */
+	dio->wait_for_completion = wait_for_completion;
 	if (!atomic_dec_and_test(&dio->ref)) {
-		if (!dio->wait_for_completion)
+		if (!wait_for_completion)
 			return -EIOCBQUEUED;
 
 		for (;;) {
@@ -1934,9 +1959,7 @@ iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter,
 		__set_current_state(TASK_RUNNING);
 	}
 
-	ret = iomap_dio_complete(dio);
-
-	return ret;
+	return iomap_dio_complete(dio);
 
 out_free_dio:
 	kfree(dio);
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 22ce3c8a2f46..0570391eaa16 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -1895,6 +1895,11 @@ static int nfs_parse_devname(const char *dev_name,
 	size_t len;
 	char *end;
 
+	if (unlikely(!dev_name || !*dev_name)) {
+		dfprintk(MOUNT, "NFS: device name not specified\n");
+		return -EINVAL;
+	}
+
 	/* Is the host name protected with square brakcets? */
 	if (*dev_name == '[') {
 		end = strchr(++dev_name, ']');
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 5a0bbf917a32..f12cb31a41e5 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -621,11 +621,12 @@ static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
 	nfs_set_page_writeback(page);
 	WARN_ON_ONCE(test_bit(PG_CLEAN, &req->wb_flags));
 
-	ret = 0;
+	ret = req->wb_context->error;
 	/* If there is a fatal error that covers this write, just exit */
-	if (nfs_error_is_fatal_on_server(req->wb_context->error))
+	if (nfs_error_is_fatal_on_server(ret))
 		goto out_launder;
 
+	ret = 0;
 	if (!nfs_pageio_add_request(pgio, req)) {
 		ret = pgio->pg_error;
 		/*
@@ -635,9 +636,9 @@ static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
 			nfs_context_set_write_error(req->wb_context, ret);
 			if (nfs_error_is_fatal_on_server(ret))
 				goto out_launder;
-		}
+		} else
+			ret = -EAGAIN;
 		nfs_redirty_request(req);
-		ret = -EAGAIN;
 	} else
 		nfs_add_stats(page_file_mapping(page)->host,
 				NFSIOS_WRITEPAGES, 1);
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 9824e32b2f23..7dc98e14655d 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -557,9 +557,11 @@ __be32 nfsd4_clone_file_range(struct file *src, u64 src_pos, struct file *dst,
 	loff_t cloned;
 
 	cloned = vfs_clone_file_range(src, src_pos, dst, dst_pos, count, 0);
+	if (cloned < 0)
+		return nfserrno(cloned);
 	if (count && cloned != count)
-		cloned = -EINVAL;
-	return nfserrno(cloned < 0 ? cloned : 0);
+		return nfserrno(-EINVAL);
+	return 0;
 }
 
 ssize_t nfsd_copy_file_range(struct file *src, u64 src_pos, struct file *dst,
diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index 105576daca4a..798f1253141a 100644
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -724,8 +724,10 @@ SYSCALL_DEFINE3(inotify_add_watch, int, fd, const char __user *, pathname,
 		return -EBADF;
 
 	/* IN_MASK_ADD and IN_MASK_CREATE don't make sense together */
-	if (unlikely((mask & IN_MASK_ADD) && (mask & IN_MASK_CREATE)))
-		return -EINVAL;
+	if (unlikely((mask & IN_MASK_ADD) && (mask & IN_MASK_CREATE))) {
+		ret = -EINVAL;
+		goto fput_and_out;
+	}
 
 	/* verify that this is indeed an inotify instance */
 	if (unlikely(f.file->f_op != &inotify_fops)) {
diff --git a/fs/proc/generic.c b/fs/proc/generic.c
index 8ae109429a88..e39bac94dead 100644
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -256,7 +256,7 @@ struct dentry *proc_lookup_de(struct inode *dir, struct dentry *dentry,
 		inode = proc_get_inode(dir->i_sb, de);
 		if (!inode)
 			return ERR_PTR(-ENOMEM);
-		d_set_d_op(dentry, &proc_misc_dentry_ops);
+		d_set_d_op(dentry, de->proc_dops);
 		return d_splice_alias(inode, dentry);
 	}
 	read_unlock(&proc_subdir_lock);
@@ -429,6 +429,8 @@ static struct proc_dir_entry *__proc_create(struct proc_dir_entry **parent,
 	INIT_LIST_HEAD(&ent->pde_openers);
 	proc_set_user(ent, (*parent)->uid, (*parent)->gid);
 
+	ent->proc_dops = &proc_misc_dentry_ops;
+
 out:
 	return ent;
 }
diff --git a/fs/proc/internal.h b/fs/proc/internal.h
index 5185d7f6a51e..95b14196f284 100644
--- a/fs/proc/internal.h
+++ b/fs/proc/internal.h
@@ -44,6 +44,7 @@ struct proc_dir_entry {
 	struct completion *pde_unload_completion;
 	const struct inode_operations *proc_iops;
 	const struct file_operations *proc_fops;
+	const struct dentry_operations *proc_dops;
 	union {
 		const struct seq_operations *seq_ops;
 		int (*single_show)(struct seq_file *, void *);
diff --git a/fs/proc/proc_net.c b/fs/proc/proc_net.c
index d5e0fcb3439e..a7b12435519e 100644
--- a/fs/proc/proc_net.c
+++ b/fs/proc/proc_net.c
@@ -38,6 +38,22 @@ static struct net *get_proc_net(const struct inode *inode)
 	return maybe_get_net(PDE_NET(PDE(inode)));
 }
 
+static int proc_net_d_revalidate(struct dentry *dentry, unsigned int flags)
+{
+	return 0;
+}
+
+static const struct dentry_operations proc_net_dentry_ops = {
+	.d_revalidate	= proc_net_d_revalidate,
+	.d_delete	= always_delete_dentry,
+};
+
+static void pde_force_lookup(struct proc_dir_entry *pde)
+{
+	/* /proc/net/ entries can be changed under us by setns(CLONE_NEWNET) */
+	pde->proc_dops = &proc_net_dentry_ops;
+}
+
 static int seq_open_net(struct inode *inode, struct file *file)
 {
 	unsigned int state_size = PDE(inode)->state_size;
@@ -90,6 +106,7 @@ struct proc_dir_entry *proc_create_net_data(const char *name, umode_t mode,
 	p = proc_create_reg(name, mode, &parent, data);
 	if (!p)
 		return NULL;
+	pde_force_lookup(p);
 	p->proc_fops = &proc_net_seq_fops;
 	p->seq_ops = ops;
 	p->state_size = state_size;
@@ -133,6 +150,7 @@ struct proc_dir_entry *proc_create_net_data_write(const char *name, umode_t mode
 	p = proc_create_reg(name, mode, &parent, data);
 	if (!p)
 		return NULL;
+	pde_force_lookup(p);
 	p->proc_fops = &proc_net_seq_fops;
 	p->seq_ops = ops;
 	p->state_size = state_size;
@@ -181,6 +199,7 @@ struct proc_dir_entry *proc_create_net_single(const char *name, umode_t mode,
 	p = proc_create_reg(name, mode, &parent, data);
 	if (!p)
 		return NULL;
+	pde_force_lookup(p);
 	p->proc_fops = &proc_net_single_fops;
 	p->single_show = show;
 	return proc_register(parent, p);
@@ -223,6 +242,7 @@ struct proc_dir_entry *proc_create_net_single_write(const char *name, umode_t mo
 	p = proc_create_reg(name, mode, &parent, data);
 	if (!p)
 		return NULL;
+	pde_force_lookup(p);
 	p->proc_fops = &proc_net_single_fops;
 	p->single_show = show;
 	p->write = write;
diff --git a/fs/xfs/scrub/repair.c b/fs/xfs/scrub/repair.c
index 1c8eecfe52b8..6acf1bfa0bfe 100644
--- a/fs/xfs/scrub/repair.c
+++ b/fs/xfs/scrub/repair.c
@@ -768,18 +768,23 @@ xrep_findroot_block(
 		if (!uuid_equal(&btblock->bb_u.s.bb_uuid,
 				&mp->m_sb.sb_meta_uuid))
 			goto out;
+		/*
+		 * Read verifiers can reference b_ops, so we set the pointer
+		 * here.  If the verifier fails we'll reset the buffer state
+		 * to what it was before we touched the buffer.
+		 */
+		bp->b_ops = fab->buf_ops;
 		fab->buf_ops->verify_read(bp);
 		if (bp->b_error) {
+			bp->b_ops = NULL;
 			bp->b_error = 0;
 			goto out;
 		}
 
 		/*
 		 * Some read verifiers will (re)set b_ops, so we must be
-		 * careful not to blow away any such assignment.
+		 * careful not to change b_ops after running the verifier.
 		 */
-		if (!bp->b_ops)
-			bp->b_ops = fab->buf_ops;
 	}
 
 	/*
diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
index 338b9d9984e0..d9048bcea49c 100644
--- a/fs/xfs/xfs_aops.c
+++ b/fs/xfs/xfs_aops.c
@@ -449,6 +449,7 @@ xfs_map_blocks(
 	}
 
 	wpc->imap = imap;
+	xfs_trim_extent_eof(&wpc->imap, ip);
 	trace_xfs_map_blocks_found(ip, offset, count, wpc->io_type, &imap);
 	return 0;
 allocate_blocks:
@@ -459,6 +460,7 @@ allocate_blocks:
 	ASSERT(whichfork == XFS_COW_FORK || cow_fsb == NULLFILEOFF ||
 	       imap.br_startoff + imap.br_blockcount <= cow_fsb);
 	wpc->imap = imap;
+	xfs_trim_extent_eof(&wpc->imap, ip);
 	trace_xfs_map_blocks_alloc(ip, offset, count, wpc->io_type, &imap);
 	return 0;
 }
diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c
index eedc5e0156ff..4f5f2ff3f70f 100644
--- a/fs/xfs/xfs_buf.c
+++ b/fs/xfs/xfs_buf.c
@@ -776,10 +776,26 @@ _xfs_buf_read(
 }
 
 /*
+ * Set buffer ops on an unchecked buffer and validate it, if possible.
+ *
  * If the caller passed in an ops structure and the buffer doesn't have ops
  * assigned, set the ops and use them to verify the contents.  If the contents
  * cannot be verified, we'll clear XBF_DONE.  We assume the buffer has no
  * recorded errors and is already in XBF_DONE state.
+ *
+ * Under normal operations, every in-core buffer must have buffer ops assigned
+ * to them when the buffer is read in from disk so that we can validate the
+ * metadata.
+ *
+ * However, there are two scenarios where one can encounter in-core buffers
+ * that don't have buffer ops.  The first is during log recovery of buffers on
+ * a V4 filesystem, though these buffers are purged at the end of recovery.
+ *
+ * The other is online repair, which tries to match arbitrary metadata blocks
+ * with btree types in order to find the root.  If online repair doesn't match
+ * the buffer with /any/ btree type, the buffer remains in memory in DONE state
+ * with no ops, and a subsequent read_buf call from elsewhere will not set the
+ * ops.  This function helps us fix this situation.
  */
 int
 xfs_buf_ensure_ops(
@@ -1536,8 +1552,7 @@ __xfs_buf_submit(
 		xfs_buf_ioerror(bp, -EIO);
 		bp->b_flags &= ~XBF_DONE;
 		xfs_buf_stale(bp);
-		if (bp->b_flags & XBF_ASYNC)
-			xfs_buf_ioend(bp);
+		xfs_buf_ioend(bp);
 		return -EIO;
 	}