diff --git a/fs/cifs/cifs_fs_sb.h b/fs/cifs/cifs_fs_sb.h
index 6e7c4427369d878f008320e32e34f29af9e5cf8e..d14002d67b6ae4a9ce21eb36634100c68836d4b6 100644
--- a/fs/cifs/cifs_fs_sb.h
+++ b/fs/cifs/cifs_fs_sb.h
@@ -58,12 +58,15 @@
 
 struct cifs_sb_info {
 	struct rb_root tlink_tree;
+	struct list_head tcon_sb_link;
 	spinlock_t tlink_tree_lock;
 	struct tcon_link *master_tlink;
 	struct nls_table *local_nls;
 	unsigned int bsize;
 	unsigned int rsize;
 	unsigned int wsize;
+	unsigned int vol_rsize;
+	unsigned int vol_wsize;
 	unsigned long actimeo; /* attribute cache timeout (jiffies) */
 	atomic_t active;
 	kuid_t	mnt_uid;
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index a6697954fd68a2ff78ccf28886677032d8cd0bd1..7d1f68008435224d40a34388599a8352112bb216 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -271,9 +271,11 @@ struct smb_version_operations {
 	/* negotiate to the server */
 	int (*negotiate)(const unsigned int, struct cifs_ses *);
 	/* set negotiated write size */
-	unsigned int (*negotiate_wsize)(struct cifs_tcon *, struct smb_vol *);
+	unsigned int (*negotiate_wsize)(struct cifs_tcon *tcon,
+					unsigned int vol_wsize);
 	/* set negotiated read size */
-	unsigned int (*negotiate_rsize)(struct cifs_tcon *, struct smb_vol *);
+	unsigned int (*negotiate_rsize)(struct cifs_tcon *tcon,
+					unsigned int vol_rsize);
 	/* setup smb sessionn */
 	int (*sess_setup)(const unsigned int, struct cifs_ses *,
 			  const struct nls_table *);
@@ -916,6 +918,9 @@ compare_mid(__u16 mid, const struct smb_hdr *smb)
 #define CIFS_DEFAULT_IOSIZE (1024 * 1024)
 #define SMB3_DEFAULT_IOSIZE (4 * 1024 * 1024)
 
+/* According to MS-SMB2 specification The minimum recommended value is 65536.*/
+#define CIFS_MIN_DEFAULT_IOSIZE (65536)
+
 /*
  * Windows only supports a max of 60kb reads and 65535 byte writes. Default to
  * those values when posix extensions aren't in force. In actuality here, we
@@ -1174,7 +1179,8 @@ struct cifs_tcon {
 #endif
 	struct list_head pending_opens;	/* list of incomplete opens */
 	struct cached_fid crfid; /* Cached root fid */
-	/* BB add field for back pointer to sb struct(s)? */
+	struct list_head cifs_sb_list;
+	spinlock_t sb_list_lock;
 #ifdef CONFIG_CIFS_DFS_UPCALL
 	char *dfs_path;
 	int remap:2;
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 07b56705bcb05a8587886a8338097855c828a66e..56afed6d9ef8f665e3f51b28e83e2f2ba0085144 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -3967,6 +3967,7 @@ int cifs_setup_cifs_sb(struct smb_vol *pvolume_info,
 			struct cifs_sb_info *cifs_sb)
 {
 	INIT_DELAYED_WORK(&cifs_sb->prune_tlinks, cifs_prune_tlinks);
+	INIT_LIST_HEAD(&cifs_sb->tcon_sb_link);
 
 	spin_lock_init(&cifs_sb->tlink_tree_lock);
 	cifs_sb->tlink_tree = RB_ROOT;
@@ -3979,6 +3980,9 @@ int cifs_setup_cifs_sb(struct smb_vol *pvolume_info,
 	cifs_sb->rsize = pvolume_info->rsize;
 	cifs_sb->wsize = pvolume_info->wsize;
 
+	cifs_sb->vol_rsize = pvolume_info->rsize;
+	cifs_sb->vol_wsize = pvolume_info->wsize;
+
 	cifs_sb->mnt_uid = pvolume_info->linux_uid;
 	cifs_sb->mnt_gid = pvolume_info->linux_gid;
 	cifs_sb->mnt_file_mode = pvolume_info->file_mode;
@@ -4205,8 +4209,8 @@ static int mount_get_conns(struct smb_vol *vol, struct cifs_sb_info *cifs_sb,
 		}
 	}
 
-	cifs_sb->wsize = server->ops->negotiate_wsize(tcon, vol);
-	cifs_sb->rsize = server->ops->negotiate_rsize(tcon, vol);
+	cifs_sb->wsize = server->ops->negotiate_wsize(tcon, cifs_sb->vol_wsize);
+	cifs_sb->rsize = server->ops->negotiate_rsize(tcon, cifs_sb->vol_rsize);
 
 	return 0;
 }
@@ -4232,6 +4236,10 @@ static int mount_setup_tlink(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
 	tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
 	spin_unlock(&cifs_sb->tlink_tree_lock);
 
+	spin_lock(&tcon->sb_list_lock);
+	list_add(&cifs_sb->tcon_sb_link, &tcon->cifs_sb_list);
+	spin_unlock(&tcon->sb_list_lock);
+
 	queue_delayed_work(cifsiod_wq, &cifs_sb->prune_tlinks,
 				TLINK_IDLE_EXPIRE);
 	return 0;
@@ -5049,9 +5057,19 @@ cifs_umount(struct cifs_sb_info *cifs_sb)
 	struct rb_root *root = &cifs_sb->tlink_tree;
 	struct rb_node *node;
 	struct tcon_link *tlink;
+	struct cifs_tcon *tcon = NULL;
 
 	cancel_delayed_work_sync(&cifs_sb->prune_tlinks);
 
+	if (cifs_sb->master_tlink) {
+		tcon = cifs_sb->master_tlink->tl_tcon;
+		if (tcon) {
+			spin_lock(&tcon->sb_list_lock);
+			list_del_init(&cifs_sb->tcon_sb_link);
+			spin_unlock(&tcon->sb_list_lock);
+		}
+	}
+
 	spin_lock(&cifs_sb->tlink_tree_lock);
 	while ((node = rb_first(root))) {
 		tlink = rb_entry(node, struct tcon_link, tl_rbnode);
diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c
index 2d46018b02839dea463dfb724847a6e8a329a581..12131a5d507303a5a0125d2c585cd59304476890 100644
--- a/fs/cifs/misc.c
+++ b/fs/cifs/misc.c
@@ -130,7 +130,9 @@ tconInfoAlloc(void)
 	++ret_buf->tc_count;
 	INIT_LIST_HEAD(&ret_buf->openFileList);
 	INIT_LIST_HEAD(&ret_buf->tcon_list);
+	INIT_LIST_HEAD(&ret_buf->cifs_sb_list);
 	spin_lock_init(&ret_buf->open_file_lock);
+	spin_lock_init(&ret_buf->sb_list_lock);
 	mutex_init(&ret_buf->crfid.fid_mutex);
 	spin_lock_init(&ret_buf->stat_lock);
 	atomic_set(&ret_buf->num_local_opens, 0);
diff --git a/fs/cifs/smb1ops.c b/fs/cifs/smb1ops.c
index 80287c26cfac0cce1e0d514bdfa94bd5305a4486..e540908bae439e8e36aed727fa0c941efd3844e0 100644
--- a/fs/cifs/smb1ops.c
+++ b/fs/cifs/smb1ops.c
@@ -428,15 +428,15 @@ cifs_negotiate(const unsigned int xid, struct cifs_ses *ses)
 }
 
 static unsigned int
-cifs_negotiate_wsize(struct cifs_tcon *tcon, struct smb_vol *volume_info)
+cifs_negotiate_wsize(struct cifs_tcon *tcon, unsigned int vol_wsize)
 {
 	__u64 unix_cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
 	struct TCP_Server_Info *server = tcon->ses->server;
 	unsigned int wsize;
 
 	/* start with specified wsize, or default */
-	if (volume_info->wsize)
-		wsize = volume_info->wsize;
+	if (vol_wsize)
+		wsize = vol_wsize;
 	else if (tcon->unix_ext && (unix_cap & CIFS_UNIX_LARGE_WRITE_CAP))
 		wsize = CIFS_DEFAULT_IOSIZE;
 	else
@@ -463,7 +463,7 @@ cifs_negotiate_wsize(struct cifs_tcon *tcon, struct smb_vol *volume_info)
 }
 
 static unsigned int
-cifs_negotiate_rsize(struct cifs_tcon *tcon, struct smb_vol *volume_info)
+cifs_negotiate_rsize(struct cifs_tcon *tcon, unsigned int vol_rsize)
 {
 	__u64 unix_cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
 	struct TCP_Server_Info *server = tcon->ses->server;
@@ -488,7 +488,7 @@ cifs_negotiate_rsize(struct cifs_tcon *tcon, struct smb_vol *volume_info)
 	else
 		defsize = server->maxBuf - sizeof(READ_RSP);
 
-	rsize = volume_info->rsize ? volume_info->rsize : defsize;
+	rsize = vol_rsize ? vol_rsize : defsize;
 
 	/*
 	 * no CAP_LARGE_READ_X? Then MS-CIFS states that we must limit this to
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index ba9456bc91e80bc6aa433edd7e5c26d135a242ce..a597490ae1f781a03b7121159d77ad6745526870 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -341,29 +341,40 @@ smb2_negotiate(const unsigned int xid, struct cifs_ses *ses)
 	return rc;
 }
 
+static inline unsigned int
+prevent_zero_iosize(unsigned int size, const char *type)
+{
+	if (size == 0) {
+		cifs_dbg(VFS, "SMB: Zero %ssize calculated, using minimum value %u\n",
+			 type, CIFS_MIN_DEFAULT_IOSIZE);
+		return CIFS_MIN_DEFAULT_IOSIZE;
+	}
+	return size;
+}
+
 static unsigned int
-smb2_negotiate_wsize(struct cifs_tcon *tcon, struct smb_vol *volume_info)
+smb2_negotiate_wsize(struct cifs_tcon *tcon, unsigned int vol_wsize)
 {
 	struct TCP_Server_Info *server = tcon->ses->server;
 	unsigned int wsize;
 
 	/* start with specified wsize, or default */
-	wsize = volume_info->wsize ? volume_info->wsize : CIFS_DEFAULT_IOSIZE;
+	wsize = vol_wsize ? vol_wsize : CIFS_DEFAULT_IOSIZE;
 	wsize = min_t(unsigned int, wsize, server->max_write);
 	if (!(server->capabilities & SMB2_GLOBAL_CAP_LARGE_MTU))
 		wsize = min_t(unsigned int, wsize, SMB2_MAX_BUFFER_SIZE);
 
-	return wsize;
+	return prevent_zero_iosize(wsize, "w");
 }
 
 static unsigned int
-smb3_negotiate_wsize(struct cifs_tcon *tcon, struct smb_vol *volume_info)
+smb3_negotiate_wsize(struct cifs_tcon *tcon, unsigned int vol_wsize)
 {
 	struct TCP_Server_Info *server = tcon->ses->server;
 	unsigned int wsize;
 
 	/* start with specified wsize, or default */
-	wsize = volume_info->wsize ? volume_info->wsize : SMB3_DEFAULT_IOSIZE;
+	wsize = vol_wsize ? vol_wsize : SMB3_DEFAULT_IOSIZE;
 	wsize = min_t(unsigned int, wsize, server->max_write);
 #ifdef CONFIG_CIFS_SMB_DIRECT
 	if (server->rdma) {
@@ -385,33 +396,33 @@ smb3_negotiate_wsize(struct cifs_tcon *tcon, struct smb_vol *volume_info)
 	if (!(server->capabilities & SMB2_GLOBAL_CAP_LARGE_MTU))
 		wsize = min_t(unsigned int, wsize, SMB2_MAX_BUFFER_SIZE);
 
-	return wsize;
+	return prevent_zero_iosize(wsize, "w");
 }
 
 static unsigned int
-smb2_negotiate_rsize(struct cifs_tcon *tcon, struct smb_vol *volume_info)
+smb2_negotiate_rsize(struct cifs_tcon *tcon, unsigned int vol_rsize)
 {
 	struct TCP_Server_Info *server = tcon->ses->server;
 	unsigned int rsize;
 
 	/* start with specified rsize, or default */
-	rsize = volume_info->rsize ? volume_info->rsize : CIFS_DEFAULT_IOSIZE;
+	rsize = vol_rsize ? vol_rsize : CIFS_DEFAULT_IOSIZE;
 	rsize = min_t(unsigned int, rsize, server->max_read);
 
 	if (!(server->capabilities & SMB2_GLOBAL_CAP_LARGE_MTU))
 		rsize = min_t(unsigned int, rsize, SMB2_MAX_BUFFER_SIZE);
 
-	return rsize;
+	return prevent_zero_iosize(rsize, "r");
 }
 
 static unsigned int
-smb3_negotiate_rsize(struct cifs_tcon *tcon, struct smb_vol *volume_info)
+smb3_negotiate_rsize(struct cifs_tcon *tcon, unsigned int vol_rsize)
 {
 	struct TCP_Server_Info *server = tcon->ses->server;
 	unsigned int rsize;
 
 	/* start with specified rsize, or default */
-	rsize = volume_info->rsize ? volume_info->rsize : SMB3_DEFAULT_IOSIZE;
+	rsize = vol_rsize ? vol_rsize : SMB3_DEFAULT_IOSIZE;
 	rsize = min_t(unsigned int, rsize, server->max_read);
 #ifdef CONFIG_CIFS_SMB_DIRECT
 	if (server->rdma) {
@@ -434,7 +445,7 @@ smb3_negotiate_rsize(struct cifs_tcon *tcon, struct smb_vol *volume_info)
 	if (!(server->capabilities & SMB2_GLOBAL_CAP_LARGE_MTU))
 		rsize = min_t(unsigned int, rsize, SMB2_MAX_BUFFER_SIZE);
 
-	return rsize;
+	return prevent_zero_iosize(rsize, "r");
 }
 
 static int
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 4197096e7fdbcc1a317d7b3b508bad39255d5336..696c84632617a5c65e9fbe4328de2aa36a9a5a7d 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -3676,6 +3676,24 @@ smb2_echo_callback(struct mid_q_entry *mid)
 	add_credits(server, &credits, CIFS_ECHO_OP);
 }
 
+static void cifs_renegotiate_iosize(struct TCP_Server_Info *server,
+				    struct cifs_tcon *tcon)
+{
+	struct cifs_sb_info *cifs_sb;
+
+	if (server == NULL || tcon == NULL)
+		return;
+
+	spin_lock(&tcon->sb_list_lock);
+	list_for_each_entry(cifs_sb, &tcon->cifs_sb_list, tcon_sb_link) {
+		cifs_sb->rsize =
+			server->ops->negotiate_rsize(tcon, cifs_sb->rsize);
+		cifs_sb->wsize =
+			server->ops->negotiate_wsize(tcon, cifs_sb->wsize);
+	}
+	spin_unlock(&tcon->sb_list_lock);
+}
+
 void smb2_reconnect_server(struct work_struct *work)
 {
 	struct TCP_Server_Info *server = container_of(work,
@@ -3724,10 +3742,12 @@ void smb2_reconnect_server(struct work_struct *work)
 
 	list_for_each_entry_safe(tcon, tcon2, &tmp_list, rlist) {
 		rc = smb2_reconnect(SMB2_INTERNAL_CMD, tcon, server);
-		if (!rc)
+		if (!rc) {
+			cifs_renegotiate_iosize(server, tcon);
 			cifs_reopen_persistent_handles(tcon);
-		else
+		} else {
 			resched = true;
+		}
 		list_del_init(&tcon->rlist);
 		if (tcon->ipc)
 			cifs_put_smb_ses(tcon->ses);