Merge tag '5.1-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6

Pull smb3 updates from Steve French:

 - smb3/cifs fixes including for large i/o error cases

 - fixes for three xfstests

 - improved crediting (smb3 flow control)

 - improved tracing

* tag '5.1-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6: (44 commits)
  fs: cifs: Kconfig: pedantic formatting
  smb3: request more credits on normal (non-large read/write) ops
  CIFS: Mask off signals when sending SMB packets
  CIFS: Return -EAGAIN instead of -ENOTSOCK
  CIFS: Only send SMB2_NEGOTIATE command on new TCP connections
  CIFS: Fix read after write for files with read caching
  smb3: for kerberos mounts display the credential uid used
  cifs: use correct format characters
  smb3: add dynamic trace point for query_info_enter/done
  smb3: add dynamic trace point for smb3_cmd_enter
  smb3: improve dynamic tracing of open and posix mkdir
  smb3: add missing read completion trace point
  smb3: Add tracepoints for read, write and query_dir enter
  smb3: add tracepoints for query dir
  smb3: Update POSIX negotiate context with POSIX ctxt GUID
  cifs: update internal module version number
  CIFS: Try to acquire credits at once for compound requests
  CIFS: Return error code when getting file handle for writeback
  CIFS: Move open file handling to writepages
  CIFS: Move unlocking pages from wdata_send_pages()
  ...

21 files changed, 929 insertions, 337 deletions

diff --git a/fs/cifs/Kconfig b/fs/cifs/Kconfig
index f1ddc9d03c10..76724efc831c 100644
--- a/fs/cifs/Kconfig
+++ b/fs/cifs/Kconfig
@@ -117,25 +117,25 @@ config CIFS_UPCALL
 	  secure Kerberos authentication is required). If unsure, say Y.
 
 config CIFS_XATTR
-        bool "CIFS extended attributes"
-        depends on CIFS
-        help
-          Extended attributes are name:value pairs associated with inodes by
-          the kernel or by users (see the attr(5) manual page for details).
-          CIFS maps the name of extended attributes beginning with the user
-          namespace prefix to SMB/CIFS EAs.  EAs are stored on Windows
-          servers without the user namespace prefix, but their names are
-          seen by Linux cifs clients prefaced by the user namespace prefix.
-          The system namespace (used by some filesystems to store ACLs) is
-          not supported at this time.
-
-          If unsure, say Y.
+	bool "CIFS extended attributes"
+	depends on CIFS
+	help
+	  Extended attributes are name:value pairs associated with inodes by
+	  the kernel or by users (see the attr(5) manual page for details).
+	  CIFS maps the name of extended attributes beginning with the user
+	  namespace prefix to SMB/CIFS EAs.  EAs are stored on Windows
+	  servers without the user namespace prefix, but their names are
+	  seen by Linux cifs clients prefaced by the user namespace prefix.
+	  The system namespace (used by some filesystems to store ACLs) is
+	  not supported at this time.
+
+	  If unsure, say Y.
 
 config CIFS_POSIX
-        bool "CIFS POSIX Extensions"
-        depends on CIFS && CIFS_ALLOW_INSECURE_LEGACY && CIFS_XATTR
-        help
-          Enabling this option will cause the cifs client to attempt to
+	bool "CIFS POSIX Extensions"
+	depends on CIFS && CIFS_ALLOW_INSECURE_LEGACY && CIFS_XATTR
+	help
+	  Enabling this option will cause the cifs client to attempt to
 	  negotiate a newer dialect with servers, such as Samba 3.0.5
 	  or later, that optionally can handle more POSIX like (rather
 	  than Windows like) file behavior.  It also enables
@@ -144,61 +144,62 @@ config CIFS_POSIX
 	  CIFS POSIX ACL support.  If unsure, say N.
 
 config CIFS_ACL
-	  bool "Provide CIFS ACL support"
-	  depends on CIFS_XATTR && KEYS
-	  help
-	    Allows fetching CIFS/NTFS ACL from the server.  The DACL blob
-	    is handed over to the application/caller.  See the man
-	    page for getcifsacl for more information.  If unsure, say Y.
+	bool "Provide CIFS ACL support"
+	depends on CIFS_XATTR && KEYS
+	help
+	  Allows fetching CIFS/NTFS ACL from the server.  The DACL blob
+	  is handed over to the application/caller.  See the man
+	  page for getcifsacl for more information.  If unsure, say Y.
 
 config CIFS_DEBUG
 	bool "Enable CIFS debugging routines"
 	default y
 	depends on CIFS
 	help
-	   Enabling this option adds helpful debugging messages to
-	   the cifs code which increases the size of the cifs module.
-	   If unsure, say Y.
+	  Enabling this option adds helpful debugging messages to
+	  the cifs code which increases the size of the cifs module.
+	  If unsure, say Y.
+
 config CIFS_DEBUG2
 	bool "Enable additional CIFS debugging routines"
 	depends on CIFS_DEBUG
 	help
-	   Enabling this option adds a few more debugging routines
-	   to the cifs code which slightly increases the size of
-	   the cifs module and can cause additional logging of debug
-	   messages in some error paths, slowing performance. This
-	   option can be turned off unless you are debugging
-	   cifs problems.  If unsure, say N.
+	  Enabling this option adds a few more debugging routines
+	  to the cifs code which slightly increases the size of
+	  the cifs module and can cause additional logging of debug
+	  messages in some error paths, slowing performance. This
+	  option can be turned off unless you are debugging
+	  cifs problems.  If unsure, say N.
 
 config CIFS_DEBUG_DUMP_KEYS
 	bool "Dump encryption keys for offline decryption (Unsafe)"
 	depends on CIFS_DEBUG
 	help
-	   Enabling this will dump the encryption and decryption keys
-	   used to communicate on an encrypted share connection on the
-	   console. This allows Wireshark to decrypt and dissect
-	   encrypted network captures. Enable this carefully.
-	   If unsure, say N.
+	  Enabling this will dump the encryption and decryption keys
+	  used to communicate on an encrypted share connection on the
+	  console. This allows Wireshark to decrypt and dissect
+	  encrypted network captures. Enable this carefully.
+	  If unsure, say N.
 
 config CIFS_DFS_UPCALL
-	  bool "DFS feature support"
-	  depends on CIFS && KEYS
-	  select DNS_RESOLVER
-	  help
-	    Distributed File System (DFS) support is used to access shares
-	    transparently in an enterprise name space, even if the share
-	    moves to a different server.  This feature also enables
-	    an upcall mechanism for CIFS which contacts userspace helper
-	    utilities to provide server name resolution (host names to
-	    IP addresses) which is needed in order to reconnect to
-	    servers if their addresses change or for implicit mounts of
-	    DFS junction points. If unsure, say Y.
+	bool "DFS feature support"
+	depends on CIFS && KEYS
+	select DNS_RESOLVER
+	help
+	  Distributed File System (DFS) support is used to access shares
+	  transparently in an enterprise name space, even if the share
+	  moves to a different server.  This feature also enables
+	  an upcall mechanism for CIFS which contacts userspace helper
+	  utilities to provide server name resolution (host names to
+	  IP addresses) which is needed in order to reconnect to
+	  servers if their addresses change or for implicit mounts of
+	  DFS junction points. If unsure, say Y.
 
 config CIFS_NFSD_EXPORT
-	  bool "Allow nfsd to export CIFS file system"
-	  depends on CIFS && BROKEN
-	  help
-	   Allows NFS server to export a CIFS mounted share (nfsd over cifs)
+	bool "Allow nfsd to export CIFS file system"
+	depends on CIFS && BROKEN
+	help
+	  Allows NFS server to export a CIFS mounted share (nfsd over cifs)
 
 config CIFS_SMB_DIRECT
 	bool "SMB Direct support (Experimental)"
@@ -209,10 +210,9 @@ config CIFS_SMB_DIRECT
 	  say N.
 
 config CIFS_FSCACHE
-	  bool "Provide CIFS client caching support"
-	  depends on CIFS=m && FSCACHE || CIFS=y && FSCACHE=y
-	  help
-	    Makes CIFS FS-Cache capable. Say Y here if you want your CIFS data
-	    to be cached locally on disk through the general filesystem cache
-	    manager. If unsure, say N.
-
+	bool "Provide CIFS client caching support"
+	depends on CIFS=m && FSCACHE || CIFS=y && FSCACHE=y
+	help
+	  Makes CIFS FS-Cache capable. Say Y here if you want your CIFS data
+	  to be cached locally on disk through the general filesystem cache
+	  manager. If unsure, say N.
diff --git a/fs/cifs/cifs_dfs_ref.c b/fs/cifs/cifs_dfs_ref.c
index d9b99abe1243..5d83c924cc47 100644
--- a/fs/cifs/cifs_dfs_ref.c
+++ b/fs/cifs/cifs_dfs_ref.c
@@ -285,9 +285,9 @@ static void dump_referral(const struct dfs_info3_param *ref)
 {
 	cifs_dbg(FYI, "DFS: ref path: %s\n", ref->path_name);
 	cifs_dbg(FYI, "DFS: node path: %s\n", ref->node_name);
-	cifs_dbg(FYI, "DFS: fl: %hd, srv_type: %hd\n",
+	cifs_dbg(FYI, "DFS: fl: %d, srv_type: %d\n",
 		 ref->flags, ref->server_type);
-	cifs_dbg(FYI, "DFS: ref_flags: %hd, path_consumed: %hd\n",
+	cifs_dbg(FYI, "DFS: ref_flags: %d, path_consumed: %d\n",
 		 ref->ref_flag, ref->path_consumed);
 }
 
diff --git a/fs/cifs/cifs_fs_sb.h b/fs/cifs/cifs_fs_sb.h
index 42f0d67f1054..ed49222abecb 100644
--- a/fs/cifs/cifs_fs_sb.h
+++ b/fs/cifs/cifs_fs_sb.h
@@ -58,6 +58,7 @@ struct cifs_sb_info {
 	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 long actimeo; /* attribute cache timeout (jiffies) */
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 62d48d486d8f..217276b8b942 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -381,7 +381,7 @@ cifs_show_security(struct seq_file *s, struct cifs_ses *ses)
 		seq_puts(s, "ntlm");
 		break;
 	case Kerberos:
-		seq_puts(s, "krb5");
+		seq_printf(s, "krb5,cruid=%u", from_kuid_munged(&init_user_ns,ses->cred_uid));
 		break;
 	case RawNTLMSSP:
 		seq_puts(s, "ntlmssp");
@@ -554,6 +554,7 @@ cifs_show_options(struct seq_file *s, struct dentry *root)
 
 	seq_printf(s, ",rsize=%u", cifs_sb->rsize);
 	seq_printf(s, ",wsize=%u", cifs_sb->wsize);
+	seq_printf(s, ",bsize=%u", cifs_sb->bsize);
 	seq_printf(s, ",echo_interval=%lu",
 			tcon->ses->server->echo_interval / HZ);
 	if (tcon->snapshot_time)
diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h
index 7652551a1fc4..142164ef1f05 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   "2.17"
+#define CIFS_VERSION   "2.18"
 #endif				/* _CIFSFS_H */
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 94dbdbe5be34..f293e052e351 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -216,6 +216,7 @@ struct cifs_io_parms;
 struct cifs_search_info;
 struct cifsInodeInfo;
 struct cifs_open_parms;
+struct cifs_credits;
 
 struct smb_version_operations {
 	int (*send_cancel)(struct TCP_Server_Info *, struct smb_rqst *,
@@ -230,12 +231,15 @@ struct smb_version_operations {
 	/* check response: verify signature, map error */
 	int (*check_receive)(struct mid_q_entry *, struct TCP_Server_Info *,
 			     bool);
-	void (*add_credits)(struct TCP_Server_Info *, const unsigned int,
-			    const int);
+	void (*add_credits)(struct TCP_Server_Info *server,
+			    const struct cifs_credits *credits,
+			    const int optype);
 	void (*set_credits)(struct TCP_Server_Info *, const int);
 	int * (*get_credits_field)(struct TCP_Server_Info *, const int);
 	unsigned int (*get_credits)(struct mid_q_entry *);
 	__u64 (*get_next_mid)(struct TCP_Server_Info *);
+	void (*revert_current_mid)(struct TCP_Server_Info *server,
+				   const unsigned int val);
 	/* data offset from read response message */
 	unsigned int (*read_data_offset)(char *);
 	/*
@@ -383,8 +387,8 @@ struct smb_version_operations {
 			 struct cifs_fid *);
 	/* calculate a size of SMB message */
 	unsigned int (*calc_smb_size)(void *buf, struct TCP_Server_Info *ptcpi);
-	/* check for STATUS_PENDING and process it in a positive case */
-	bool (*is_status_pending)(char *, struct TCP_Server_Info *, int);
+	/* check for STATUS_PENDING and process the response if yes */
+	bool (*is_status_pending)(char *buf, struct TCP_Server_Info *server);
 	/* check for STATUS_NETWORK_SESSION_EXPIRED */
 	bool (*is_session_expired)(char *);
 	/* send oplock break response */
@@ -452,7 +456,11 @@ struct smb_version_operations {
 	unsigned int (*wp_retry_size)(struct inode *);
 	/* get mtu credits */
 	int (*wait_mtu_credits)(struct TCP_Server_Info *, unsigned int,
-				unsigned int *, unsigned int *);
+				unsigned int *, struct cifs_credits *);
+	/* adjust previously taken mtu credits to request size */
+	int (*adjust_credits)(struct TCP_Server_Info *server,
+			      struct cifs_credits *credits,
+			      const unsigned int payload_size);
 	/* check if we need to issue closedir */
 	bool (*dir_needs_close)(struct cifsFileInfo *);
 	long (*fallocate)(struct file *, struct cifs_tcon *, int, loff_t,
@@ -557,6 +565,7 @@ struct smb_vol {
 	bool resilient:1; /* noresilient not required since not fored for CA */
 	bool domainauto:1;
 	bool rdma:1;
+	unsigned int bsize;
 	unsigned int rsize;
 	unsigned int wsize;
 	bool sockopt_tcp_nodelay:1;
@@ -710,6 +719,11 @@ struct TCP_Server_Info {
 	int nr_targets;
 };
 
+struct cifs_credits {
+	unsigned int value;
+	unsigned int instance;
+};
+
 static inline unsigned int
 in_flight(struct TCP_Server_Info *server)
 {
@@ -731,18 +745,18 @@ has_credits(struct TCP_Server_Info *server, int *credits)
 }
 
 static inline void
-add_credits(struct TCP_Server_Info *server, const unsigned int add,
+add_credits(struct TCP_Server_Info *server, const struct cifs_credits *credits,
 	    const int optype)
 {
-	server->ops->add_credits(server, add, optype);
+	server->ops->add_credits(server, credits, optype);
 }
 
 static inline void
-add_credits_and_wake_if(struct TCP_Server_Info *server, const unsigned int add,
-			const int optype)
+add_credits_and_wake_if(struct TCP_Server_Info *server,
+			const struct cifs_credits *credits, const int optype)
 {
-	if (add) {
-		server->ops->add_credits(server, add, optype);
+	if (credits->value) {
+		server->ops->add_credits(server, credits, optype);
 		wake_up(&server->request_q);
 	}
 }
@@ -753,6 +767,14 @@ set_credits(struct TCP_Server_Info *server, const int val)
 	server->ops->set_credits(server, val);
 }
 
+static inline int
+adjust_credits(struct TCP_Server_Info *server, struct cifs_credits *credits,
+	       const unsigned int payload_size)
+{
+	return server->ops->adjust_credits ?
+		server->ops->adjust_credits(server, credits, payload_size) : 0;
+}
+
 static inline __le64
 get_next_mid64(struct TCP_Server_Info *server)
 {
@@ -770,6 +792,22 @@ get_next_mid(struct TCP_Server_Info *server)
 	return cpu_to_le16(mid);
 }
 
+static inline void
+revert_current_mid(struct TCP_Server_Info *server, const unsigned int val)
+{
+	if (server->ops->revert_current_mid)
+		server->ops->revert_current_mid(server, val);
+}
+
+static inline void
+revert_current_mid_from_hdr(struct TCP_Server_Info *server,
+			    const struct smb2_sync_hdr *shdr)
+{
+	unsigned int num = le16_to_cpu(shdr->CreditCharge);
+
+	return revert_current_mid(server, num > 0 ? num : 1);
+}
+
 static inline __u16
 get_mid(const struct smb_hdr *smb)
 {
@@ -1234,7 +1272,7 @@ struct cifs_readdata {
 	unsigned int			pagesz;
 	unsigned int			page_offset;
 	unsigned int			tailsz;
-	unsigned int			credits;
+	struct cifs_credits		credits;
 	unsigned int			nr_pages;
 	struct page			**pages;
 };
@@ -1260,7 +1298,7 @@ struct cifs_writedata {
 	unsigned int			pagesz;
 	unsigned int			page_offset;
 	unsigned int			tailsz;
-	unsigned int			credits;
+	struct cifs_credits		credits;
 	unsigned int			nr_pages;
 	struct page			**pages;
 };
@@ -1422,6 +1460,7 @@ struct mid_q_entry {
 	struct kref refcount;
 	struct TCP_Server_Info *server;	/* server corresponding to this mid */
 	__u64 mid;		/* multiplex id */
+	__u16 credits;		/* number of credits consumed by this mid */
 	__u32 pid;		/* process id */
 	__u32 sequence_number;  /* for CIFS signing */
 	unsigned long when_alloc;  /* when mid was created */
diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index 336c116995d7..4f96b3b00a7a 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -93,7 +93,8 @@ extern int cifs_discard_remaining_data(struct TCP_Server_Info *server);
 extern int cifs_call_async(struct TCP_Server_Info *server,
 			struct smb_rqst *rqst,
 			mid_receive_t *receive, mid_callback_t *callback,
-			mid_handle_t *handle, void *cbdata, const int flags);
+			mid_handle_t *handle, void *cbdata, const int flags,
+			const struct cifs_credits *exist_credits);
 extern int cifs_send_recv(const unsigned int xid, struct cifs_ses *ses,
 			  struct smb_rqst *rqst, int *resp_buf_type,
 			  const int flags, struct kvec *resp_iov);
@@ -115,7 +116,7 @@ extern int cifs_check_receive(struct mid_q_entry *mid,
 			struct TCP_Server_Info *server, bool log_error);
 extern int cifs_wait_mtu_credits(struct TCP_Server_Info *server,
 				 unsigned int size, unsigned int *num,
-				 unsigned int *credits);
+				 struct cifs_credits *credits);
 extern int SendReceive2(const unsigned int /* xid */ , struct cifs_ses *,
 			struct kvec *, int /* nvec to send */,
 			int * /* type of buf returned */, const int flags,
@@ -133,6 +134,9 @@ extern bool is_size_safe_to_change(struct cifsInodeInfo *, __u64 eof);
 extern void cifs_update_eof(struct cifsInodeInfo *cifsi, loff_t offset,
 			    unsigned int bytes_written);
 extern struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *, bool);
+extern int cifs_get_writable_file(struct cifsInodeInfo *cifs_inode,
+				  bool fsuid_only,
+				  struct cifsFileInfo **ret_file);
 extern struct cifsFileInfo *find_readable_file(struct cifsInodeInfo *, bool);
 extern unsigned int smbCalcSize(void *buf, struct TCP_Server_Info *server);
 extern int decode_negTokenInit(unsigned char *security_blob, int length,
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index bb54ccf8481c..f43747c062a7 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -139,8 +139,8 @@ static int __cifs_reconnect_tcon(const struct nls_table *nlsc,
 		return -ENOMEM;
 
 	if (tcon->ipc) {
-		snprintf(tree, MAX_TREE_SIZE, "\\\\%s\\IPC$",
-			 tcon->ses->server->hostname);
+		scnprintf(tree, MAX_TREE_SIZE, "\\\\%s\\IPC$",
+			  tcon->ses->server->hostname);
 		rc = CIFSTCon(0, tcon->ses, tree, tcon, nlsc);
 		goto out;
 	}
@@ -172,7 +172,7 @@ static int __cifs_reconnect_tcon(const struct nls_table *nlsc,
 			continue;
 		}
 
-		snprintf(tree, MAX_TREE_SIZE, "\\%s", tgt);
+		scnprintf(tree, MAX_TREE_SIZE, "\\%s", tgt);
 
 		rc = CIFSTCon(0, tcon->ses, tree, tcon, nlsc);
 		if (!rc)
@@ -822,9 +822,10 @@ static void
 cifs_echo_callback(struct mid_q_entry *mid)
 {
 	struct TCP_Server_Info *server = mid->callback_data;
+	struct cifs_credits credits = { .value = 1, .instance = 0 };
 
 	DeleteMidQEntry(mid);
-	add_credits(server, 1, CIFS_ECHO_OP);
+	add_credits(server, &credits, CIFS_ECHO_OP);
 }
 
 int
@@ -859,7 +860,7 @@ CIFSSMBEcho(struct TCP_Server_Info *server)
 	iov[1].iov_base = (char *)smb + 4;
 
 	rc = cifs_call_async(server, &rqst, NULL, cifs_echo_callback, NULL,
-			     server, CIFS_ASYNC_OP | CIFS_ECHO_OP);
+			     server, CIFS_ASYNC_OP | CIFS_ECHO_OP, NULL);
 	if (rc)
 		cifs_dbg(FYI, "Echo request failed: %d\n", rc);
 
@@ -1605,16 +1606,17 @@ cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid)
 	}
 
 	if (server->ops->is_status_pending &&
-	    server->ops->is_status_pending(buf, server, 0)) {
+	    server->ops->is_status_pending(buf, server)) {
 		cifs_discard_remaining_data(server);
 		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;
+	rdata->iov[0].iov_len = server->vals->header_preamble_size;
+	rdata->iov[1].iov_base = buf + server->vals->header_preamble_size;
+	rdata->iov[1].iov_len =
+		server->total_read - server->vals->header_preamble_size;
 	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",
@@ -1713,6 +1715,7 @@ cifs_readv_callback(struct mid_q_entry *mid)
 				 .rq_npages = rdata->nr_pages,
 				 .rq_pagesz = rdata->pagesz,
 				 .rq_tailsz = rdata->tailsz };
+	struct cifs_credits credits = { .value = 1, .instance = 0 };
 
 	cifs_dbg(FYI, "%s: mid=%llu state=%d result=%d bytes=%u\n",
 		 __func__, mid->mid, mid->mid_state, rdata->result,
@@ -1750,7 +1753,7 @@ cifs_readv_callback(struct mid_q_entry *mid)
 
 	queue_work(cifsiod_wq, &rdata->work);
 	DeleteMidQEntry(mid);
-	add_credits(server, 1, 0);
+	add_credits(server, &credits, 0);
 }
 
 /* cifs_async_readv - send an async write, and set up mid to handle result */
@@ -1809,7 +1812,7 @@ cifs_async_readv(struct cifs_readdata *rdata)
 
 	kref_get(&rdata->refcount);
 	rc = cifs_call_async(tcon->ses->server, &rqst, cifs_readv_receive,
-			     cifs_readv_callback, NULL, rdata, 0);
+			     cifs_readv_callback, NULL, rdata, 0, NULL);
 
 	if (rc == 0)
 		cifs_stats_inc(&tcon->stats.cifs_stats.num_reads);
@@ -2123,14 +2126,18 @@ cifs_writev_requeue(struct cifs_writedata *wdata)
 		wdata2->tailsz = tailsz;
 		wdata2->bytes = cur_len;
 
-		wdata2->cfile = find_writable_file(CIFS_I(inode), false);
+		rc = cifs_get_writable_file(CIFS_I(inode), false,
+					    &wdata2->cfile);
 		if (!wdata2->cfile) {
-			cifs_dbg(VFS, "No writable handles for inode\n");
-			rc = -EBADF;
-			break;
+			cifs_dbg(VFS, "No writable handle to retry writepages rc=%d\n",
+				 rc);
+			if (!is_retryable_error(rc))
+				rc = -EBADF;
+		} else {
+			wdata2->pid = wdata2->cfile->pid;
+			rc = server->ops->async_writev(wdata2,
+						       cifs_writedata_release);
 		}
-		wdata2->pid = wdata2->cfile->pid;
-		rc = server->ops->async_writev(wdata2, cifs_writedata_release);
 
 		for (j = 0; j < nr_pages; j++) {
 			unlock_page(wdata2->pages[j]);
@@ -2145,6 +2152,7 @@ cifs_writev_requeue(struct cifs_writedata *wdata)
 			kref_put(&wdata2->refcount, cifs_writedata_release);
 			if (is_retryable_error(rc))
 				continue;
+			i += nr_pages;
 			break;
 		}
 
@@ -2152,6 +2160,13 @@ cifs_writev_requeue(struct cifs_writedata *wdata)
 		i += nr_pages;
 	} while (i < wdata->nr_pages);
 
+	/* cleanup remaining pages from the original wdata */
+	for (; i < wdata->nr_pages; i++) {
+		SetPageError(wdata->pages[i]);
+		end_page_writeback(wdata->pages[i]);
+		put_page(wdata->pages[i]);
+	}
+
 	if (rc != 0 && !is_retryable_error(rc))
 		mapping_set_error(inode->i_mapping, rc);
 	kref_put(&wdata->refcount, cifs_writedata_release);
@@ -2226,6 +2241,7 @@ cifs_writev_callback(struct mid_q_entry *mid)
 	struct cifs_tcon *tcon = tlink_tcon(wdata->cfile->tlink);
 	unsigned int written;
 	WRITE_RSP *smb = (WRITE_RSP *)mid->resp_buf;
+	struct cifs_credits credits = { .value = 1, .instance = 0 };
 
 	switch (mid->mid_state) {
 	case MID_RESPONSE_RECEIVED:
@@ -2261,7 +2277,7 @@ cifs_writev_callback(struct mid_q_entry *mid)
 
 	queue_work(cifsiod_wq, &wdata->work);
 	DeleteMidQEntry(mid);
-	add_credits(tcon->ses->server, 1, 0);
+	add_credits(tcon->ses->server, &credits, 0);
 }
 
 /* cifs_async_writev - send an async write, and set up mid to handle result */
@@ -2339,7 +2355,7 @@ cifs_async_writev(struct cifs_writedata *wdata,
 
 	kref_get(&wdata->refcount);
 	rc = cifs_call_async(tcon->ses->server, &rqst, NULL,
-				cifs_writev_callback, NULL, wdata, 0);
+			     cifs_writev_callback, NULL, wdata, 0, NULL);
 
 	if (rc == 0)
 		cifs_stats_inc(&tcon->stats.cifs_stats.num_writes);
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 8463c940e0e5..b95db2b593cb 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -102,7 +102,7 @@ enum {
 	Opt_backupuid, Opt_backupgid, Opt_uid,
 	Opt_cruid, Opt_gid, Opt_file_mode,
 	Opt_dirmode, Opt_port,
-	Opt_rsize, Opt_wsize, Opt_actimeo,
+	Opt_blocksize, Opt_rsize, Opt_wsize, Opt_actimeo,
 	Opt_echo_interval, Opt_max_credits,
 	Opt_snapshot,
 
@@ -204,6 +204,7 @@ static const match_table_t cifs_mount_option_tokens = {
 	{ Opt_dirmode, "dirmode=%s" },
 	{ Opt_dirmode, "dir_mode=%s" },
 	{ Opt_port, "port=%s" },
+	{ Opt_blocksize, "bsize=%s" },
 	{ Opt_rsize, "rsize=%s" },
 	{ Opt_wsize, "wsize=%s" },
 	{ Opt_actimeo, "actimeo=%s" },
@@ -348,7 +349,7 @@ static int reconn_set_ipaddr(struct TCP_Server_Info *server)
 		cifs_dbg(FYI, "%s: failed to create UNC path\n", __func__);
 		return -ENOMEM;
 	}
-	snprintf(unc, len, "\\\\%s", server->hostname);
+	scnprintf(unc, len, "\\\\%s", server->hostname);
 
 	rc = dns_resolve_server_name_to_ip(unc, &ipaddr);
 	kfree(unc);
@@ -592,6 +593,7 @@ cifs_reconnect(struct TCP_Server_Info *server)
 			msleep(3000);
 		} else {
 			atomic_inc(&tcpSesReconnectCount);
+			set_credits(server, 1);
 			spin_lock(&GlobalMid_Lock);
 			if (server->tcpStatus != CifsExiting)
 				server->tcpStatus = CifsNeedNegotiate;
@@ -1053,7 +1055,7 @@ cifs_handle_standard(struct TCP_Server_Info *server, struct mid_q_entry *mid)
 	}
 
 	if (server->ops->is_status_pending &&
-	    server->ops->is_status_pending(buf, server, length))
+	    server->ops->is_status_pending(buf, server))
 		return -1;
 
 	if (!mid)
@@ -1063,6 +1065,26 @@ cifs_handle_standard(struct TCP_Server_Info *server, struct mid_q_entry *mid)
 	return 0;
 }
 
+static void
+smb2_add_credits_from_hdr(char *buffer, struct TCP_Server_Info *server)
+{
+	struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)buffer;
+
+	/*
+	 * SMB1 does not use credits.
+	 */
+	if (server->vals->header_preamble_size)
+		return;
+
+	if (shdr->CreditRequest) {
+		spin_lock(&server->req_lock);
+		server->credits += le16_to_cpu(shdr->CreditRequest);
+		spin_unlock(&server->req_lock);
+		wake_up(&server->request_q);
+	}
+}
+
+
 static int
 cifs_demultiplex_thread(void *p)
 {
@@ -1192,6 +1214,7 @@ next_pdu:
 			} else if (server->ops->is_oplock_break &&
 				   server->ops->is_oplock_break(bufs[i],
 								server)) {
+				smb2_add_credits_from_hdr(bufs[i], server);
 				cifs_dbg(FYI, "Received oplock break\n");
 			} else {
 				cifs_dbg(VFS, "No task to wake, unknown frame "
@@ -1203,6 +1226,7 @@ next_pdu:
 				if (server->ops->dump_detail)
 					server->ops->dump_detail(bufs[i],
 								 server);
+				smb2_add_credits_from_hdr(bufs[i], server);
 				cifs_dump_mids(server);
 #endif /* CIFS_DEBUG2 */
 			}
@@ -1486,6 +1510,11 @@ cifs_parse_devname(const char *devname, struct smb_vol *vol)
 	const char *delims = "/\\";
 	size_t len;
 
+	if (unlikely(!devname || !*devname)) {
+		cifs_dbg(VFS, "Device name not specified.\n");
+		return -EINVAL;
+	}
+
 	/* make sure we have a valid UNC double delimiter prefix */
 	len = strspn(devname, delims);
 	if (len != 2)
@@ -1571,7 +1600,7 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
 	vol->cred_uid = current_uid();
 	vol->linux_uid = current_uid();
 	vol->linux_gid = current_gid();
-
+	vol->bsize = 1024 * 1024; /* can improve cp performance significantly */
 	/*
 	 * default to SFM style remapping of seven reserved characters
 	 * unless user overrides it or we negotiate CIFS POSIX where
@@ -1944,6 +1973,26 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
 			}
 			port = (unsigned short)option;
 			break;
+		case Opt_blocksize:
+			if (get_option_ul(args, &option)) {
+				cifs_dbg(VFS, "%s: Invalid blocksize value\n",
+					__func__);
+				goto cifs_parse_mount_err;
+			}
+			/*
+			 * inode blocksize realistically should never need to be
+			 * less than 16K or greater than 16M and default is 1MB.
+			 * Note that small inode block sizes (e.g. 64K) can lead
+			 * to very poor performance of common tools like cp and scp
+			 */
+			if ((option < CIFS_MAX_MSGSIZE) ||
+			   (option > (4 * SMB3_DEFAULT_IOSIZE))) {
+				cifs_dbg(VFS, "%s: Invalid blocksize\n",
+					__func__);
+				goto cifs_parse_mount_err;
+			}
+			vol->bsize = option;
+			break;
 		case Opt_rsize:
 			if (get_option_ul(args, &option)) {
 				cifs_dbg(VFS, "%s: Invalid rsize value\n",
@@ -2609,7 +2658,7 @@ cifs_get_tcp_session(struct smb_vol *volume_info)
 		volume_info->target_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
 	tcp_ses->session_estab = false;
 	tcp_ses->sequence_number = 0;
-	tcp_ses->reconnect_instance = 0;
+	tcp_ses->reconnect_instance = 1;
 	tcp_ses->lstrp = jiffies;
 	spin_lock_init(&tcp_ses->req_lock);
 	INIT_LIST_HEAD(&tcp_ses->tcp_ses_list);
@@ -2770,7 +2819,7 @@ cifs_setup_ipc(struct cifs_ses *ses, struct smb_vol *volume_info)
 	if (tcon == NULL)
 		return -ENOMEM;
 
-	snprintf(unc, sizeof(unc), "\\\\%s\\IPC$", ses->server->hostname);
+	scnprintf(unc, sizeof(unc), "\\\\%s\\IPC$", ses->server->hostname);
 
 	/* cannot fail */
 	nls_codepage = load_nls_default();
@@ -3839,6 +3888,7 @@ int cifs_setup_cifs_sb(struct smb_vol *pvolume_info,
 	spin_lock_init(&cifs_sb->tlink_tree_lock);
 	cifs_sb->tlink_tree = RB_ROOT;
 
+	cifs_sb->bsize = pvolume_info->bsize;
 	/*
 	 * Temporarily set r/wsize for matching superblock. If we end up using
 	 * new sb then client will later negotiate it downward if needed.
@@ -4198,7 +4248,7 @@ static int update_vol_info(const struct dfs_cache_tgt_iterator *tgt_it,
 	new_unc = kmalloc(len, GFP_KERNEL);
 	if (!new_unc)
 		return -ENOMEM;
-	snprintf(new_unc, len, "\\%s", tgt);
+	scnprintf(new_unc, len, "\\%s", tgt);
 
 	kfree(vol->UNC);
 	vol->UNC = new_unc;
@@ -4902,8 +4952,6 @@ cifs_negotiate_protocol(const unsigned int xid, struct cifs_ses *ses)
 	if (!server->ops->need_neg(server))
 		return 0;
 
-	set_credits(server, 1);
-
 	rc = server->ops->negotiate(xid, ses);
 	if (rc == 0) {
 		spin_lock(&GlobalMid_Lock);
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 659ce1b92c44..4c144c1f50eb 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -1842,24 +1842,30 @@ struct cifsFileInfo *find_readable_file(struct cifsInodeInfo *cifs_inode,
 	return NULL;
 }
 
-struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode,
-					bool fsuid_only)
+/* Return -EBADF if no handle is found and general rc otherwise */
+int
+cifs_get_writable_file(struct cifsInodeInfo *cifs_inode, bool fsuid_only,
+		       struct cifsFileInfo **ret_file)
 {
 	struct cifsFileInfo *open_file, *inv_file = NULL;
 	struct cifs_sb_info *cifs_sb;
 	struct cifs_tcon *tcon;
 	bool any_available = false;
-	int rc;
+	int rc = -EBADF;
 	unsigned int refind = 0;
 
-	/* Having a null inode here (because mapping->host was set to zero by
-	the VFS or MM) should not happen but we had reports of on oops (due to
-	it being zero) during stress testcases so we need to check for it */
+	*ret_file = NULL;
+
+	/*
+	 * Having a null inode here (because mapping->host was set to zero by
+	 * the VFS or MM) should not happen but we had reports of on oops (due
+	 * to it being zero) during stress testcases so we need to check for it
+	 */
 
 	if (cifs_inode == NULL) {
 		cifs_dbg(VFS, "Null inode passed to cifs_writeable_file\n");
 		dump_stack();
-		return NULL;
+		return rc;
 	}
 
 	cifs_sb = CIFS_SB(cifs_inode->vfs_inode.i_sb);
@@ -1873,7 +1879,7 @@ struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode,
 refind_writable:
 	if (refind > MAX_REOPEN_ATT) {
 		spin_unlock(&tcon->open_file_lock);
-		return NULL;
+		return rc;
 	}
 	list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
 		if (!any_available && open_file->pid != current->tgid)
@@ -1885,7 +1891,8 @@ refind_writable:
 				/* found a good writable file