Merge tag '5.14-rc-smb3-fixes-part1' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs updates from Steve French:

 - improve fallocate emulation

 - DFS fixes

 - minor multichannel fixes

 - various cleanup patches, many to address Coverity warnings

* tag '5.14-rc-smb3-fixes-part1' of git://git.samba.org/sfrench/cifs-2.6: (38 commits)
  smb3: prevent races updating CurrentMid
  cifs: fix missing spinlock around update to ses->status
  cifs: missing null pointer check in cifs_mount
  smb3: fix possible access to uninitialized pointer to DACL
  cifs: missing null check for newinode pointer
  cifs: remove two cases where rc is set unnecessarily in sid_to_id
  SMB3: Add new info level for query directory
  cifs: fix NULL dereference in smb2_check_message()
  smbdirect: missing rc checks while waiting for rdma events
  cifs: Avoid field over-reading memcpy()
  smb311: remove dead code for non compounded posix query info
  cifs: fix SMB1 error path in cifs_get_file_info_unix
  smb3: fix uninitialized value for port in witness protocol move
  cifs: fix unneeded null check
  cifs: use SPDX-Licence-Identifier
  cifs: convert list_for_each to entry variant in cifs_debug.c
  cifs: convert list_for_each to entry variant in smb2misc.c
  cifs: avoid extra calls in posix_info_parse
  cifs: retry lookup and readdir when EAGAIN is returned.
  cifs: fix check of dfs interlinks
  ...

57 files changed, 966 insertions, 1949 deletions

diff --git a/fs/cifs/Kconfig b/fs/cifs/Kconfig
index bf52e9326ebe..7364950a9ef4 100644
--- a/fs/cifs/Kconfig
+++ b/fs/cifs/Kconfig
@@ -19,6 +19,8 @@ config CIFS
 	select CRYPTO_LIB_DES
 	select KEYS
 	select DNS_RESOLVER
+	select ASN1
+	select OID_REGISTRY
 	help
 	  This is the client VFS module for the SMB3 family of NAS protocols,
 	  (including support for the most recent, most secure dialect SMB3.1.1)
@@ -57,6 +59,7 @@ config CIFS
 config CIFS_STATS2
 	bool "Extended statistics"
 	depends on CIFS
+	default y
 	help
 	  Enabling this option will allow more detailed statistics on SMB
 	  request timing to be displayed in /proc/fs/cifs/DebugData and also
@@ -65,8 +68,7 @@ config CIFS_STATS2
 	  for more details. These additional statistics may have a minor effect
 	  on performance and memory utilization.
 
-	  Unless you are a developer or are doing network performance analysis
-	  or tuning, say N.
+	  If unsure, say Y.
 
 config CIFS_ALLOW_INSECURE_LEGACY
 	bool "Support legacy servers which use less secure dialects"
diff --git a/fs/cifs/Makefile b/fs/cifs/Makefile
index 3ee3b7de4ded..87fcacdf3de7 100644
--- a/fs/cifs/Makefile
+++ b/fs/cifs/Makefile
@@ -6,12 +6,16 @@ ccflags-y += -I$(src)		# needed for trace events
 obj-$(CONFIG_CIFS) += cifs.o
 
 cifs-y := trace.o cifsfs.o cifssmb.o cifs_debug.o connect.o dir.o file.o \
-	  inode.o link.o misc.o netmisc.o smbencrypt.o transport.o asn1.o \
+	  inode.o link.o misc.o netmisc.o smbencrypt.o transport.o \
 	  cifs_unicode.o nterr.o cifsencrypt.o \
 	  readdir.o ioctl.o sess.o export.o smb1ops.o unc.o winucase.o \
 	  smb2ops.o smb2maperror.o smb2transport.o \
 	  smb2misc.o smb2pdu.o smb2inode.o smb2file.o cifsacl.o fs_context.o \
-	  dns_resolve.o
+	  dns_resolve.o cifs_spnego_negtokeninit.asn1.o asn1.o
+
+$(obj)/asn1.o: $(obj)/cifs_spnego_negtokeninit.asn1.h
+
+$(obj)/cifs_spnego_negtokeninit.asn1.o: $(obj)/cifs_spnego_negtokeninit.asn1.c $(obj)/cifs_spnego_negtokeninit.asn1.h
 
 cifs-$(CONFIG_CIFS_XATTR) += xattr.o
 
diff --git a/fs/cifs/asn1.c b/fs/cifs/asn1.c
index 3150c19cdc2f..b5724ef9f182 100644
--- a/fs/cifs/asn1.c
+++ b/fs/cifs/asn1.c
@@ -1,612 +1,63 @@
 // SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * The ASB.1/BER parsing code is derived from ip_nat_snmp_basic.c which was in
- * turn derived from the gxsnmp package by Gregory McLean & Jochen Friedrich
- *
- * Copyright (c) 2000 RP Internet (www.rpi.net.au).
- */
 
 #include <linux/module.h>
-#include <linux/types.h>
 #include <linux/kernel.h>
-#include <linux/mm.h>
-#include <linux/slab.h>
-#include "cifspdu.h"
+#include <linux/oid_registry.h>
 #include "cifsglob.h"
 #include "cifs_debug.h"
 #include "cifsproto.h"
+#include "cifs_spnego_negtokeninit.asn1.h"
 
-/*****************************************************************************
- *
- * Basic ASN.1 decoding routines (gxsnmp author Dirk Wisse)
- *
- *****************************************************************************/
-
-/* Class */
-#define ASN1_UNI	0	/* Universal */
-#define ASN1_APL	1	/* Application */
-#define ASN1_CTX	2	/* Context */
-#define ASN1_PRV	3	/* Private */
-
-/* Tag */
-#define ASN1_EOC	0	/* End Of Contents or N/A */
-#define ASN1_BOL	1	/* Boolean */
-#define ASN1_INT	2	/* Integer */
-#define ASN1_BTS	3	/* Bit String */
-#define ASN1_OTS	4	/* Octet String */
-#define ASN1_NUL	5	/* Null */
-#define ASN1_OJI	6	/* Object Identifier  */
-#define ASN1_OJD	7	/* Object Description */
-#define ASN1_EXT	8	/* External */
-#define ASN1_ENUM	10	/* Enumerated */
-#define ASN1_SEQ	16	/* Sequence */
-#define ASN1_SET	17	/* Set */
-#define ASN1_NUMSTR	18	/* Numerical String */
-#define ASN1_PRNSTR	19	/* Printable String */
-#define ASN1_TEXSTR	20	/* Teletext String */
-#define ASN1_VIDSTR	21	/* Video String */
-#define ASN1_IA5STR	22	/* IA5 String */
-#define ASN1_UNITIM	23	/* Universal Time */
-#define ASN1_GENTIM	24	/* General Time */
-#define ASN1_GRASTR	25	/* Graphical String */
-#define ASN1_VISSTR	26	/* Visible String */
-#define ASN1_GENSTR	27	/* General String */
-
-/* Primitive / Constructed methods*/
-#define ASN1_PRI	0	/* Primitive */
-#define ASN1_CON	1	/* Constructed */
-
-/*
- * Error codes.
- */
-#define ASN1_ERR_NOERROR		0
-#define ASN1_ERR_DEC_EMPTY		2
-#define ASN1_ERR_DEC_EOC_MISMATCH	3
-#define ASN1_ERR_DEC_LENGTH_MISMATCH	4
-#define ASN1_ERR_DEC_BADVALUE		5
-
-#define SPNEGO_OID_LEN 7
-#define NTLMSSP_OID_LEN  10
-#define KRB5_OID_LEN  7
-#define KRB5U2U_OID_LEN  8
-#define MSKRB5_OID_LEN  7
-static unsigned long SPNEGO_OID[7] = { 1, 3, 6, 1, 5, 5, 2 };
-static unsigned long NTLMSSP_OID[10] = { 1, 3, 6, 1, 4, 1, 311, 2, 2, 10 };
-static unsigned long KRB5_OID[7] = { 1, 2, 840, 113554, 1, 2, 2 };
-static unsigned long KRB5U2U_OID[8] = { 1, 2, 840, 113554, 1, 2, 2, 3 };
-static unsigned long MSKRB5_OID[7] = { 1, 2, 840, 48018, 1, 2, 2 };
-
-/*
- * ASN.1 context.
- */
-struct asn1_ctx {
-	int error;		/* Error condition */
-	unsigned char *pointer;	/* Octet just to be decoded */
-	unsigned char *begin;	/* First octet */
-	unsigned char *end;	/* Octet after last octet */
-};
-
-/*
- * Octet string (not null terminated)
- */
-struct asn1_octstr {
-	unsigned char *data;
-	unsigned int len;
-};
-
-static void
-asn1_open(struct asn1_ctx *ctx, unsigned char *buf, unsigned int len)
-{
-	ctx->begin = buf;
-	ctx->end = buf + len;
-	ctx->pointer = buf;
-	ctx->error = ASN1_ERR_NOERROR;
-}
-
-static unsigned char
-asn1_octet_decode(struct asn1_ctx *ctx, unsigned char *ch)
-{
-	if (ctx->pointer >= ctx->end) {
-		ctx->error = ASN1_ERR_DEC_EMPTY;
-		return 0;
-	}
-	*ch = *(ctx->pointer)++;
-	return 1;
-}
-
-#if 0 /* will be needed later by spnego decoding/encoding of ntlmssp */
-static unsigned char
-asn1_enum_decode(struct asn1_ctx *ctx, __le32 *val)
-{
-	unsigned char ch;
-
-	if (ctx->pointer >= ctx->end) {
-		ctx->error = ASN1_ERR_DEC_EMPTY;
-		return 0;
-	}
-
-	ch = *(ctx->pointer)++; /* ch has 0xa, ptr points to length octet */
-	if ((ch) == ASN1_ENUM)  /* if ch value is ENUM, 0xa */
-		*val = *(++(ctx->pointer)); /* value has enum value */
-	else
-		return 0;
-
-	ctx->pointer++;
-	return 1;
-}
-#endif
-
-static unsigned char
-asn1_tag_decode(struct asn1_ctx *ctx, unsigned int *tag)
-{
-	unsigned char ch;
-
-	*tag = 0;
-
-	do {
-		if (!asn1_octet_decode(ctx, &ch))
-			return 0;
-		*tag <<= 7;
-		*tag |= ch & 0x7F;
-	} while ((ch & 0x80) == 0x80);
-	return 1;
-}
-
-static unsigned char
-asn1_id_decode(struct asn1_ctx *ctx,
-	       unsigned int *cls, unsigned int *con, unsigned int *tag)
-{
-	unsigned char ch;
-
-	if (!asn1_octet_decode(ctx, &ch))
-		return 0;
-
-	*cls = (ch & 0xC0) >> 6;
-	*con = (ch & 0x20) >> 5;
-	*tag = (ch & 0x1F);
-
-	if (*tag == 0x1F) {
-		if (!asn1_tag_decode(ctx, tag))
-			return 0;
-	}
-	return 1;
-}
-
-static unsigned char
-asn1_length_decode(struct asn1_ctx *ctx, unsigned int *def, unsigned int *len)
-{
-	unsigned char ch, cnt;
-
-	if (!asn1_octet_decode(ctx, &ch))
-		return 0;
-
-	if (ch == 0x80)
-		*def = 0;
-	else {
-		*def = 1;
-
-		if (ch < 0x80)
-			*len = ch;
-		else {
-			cnt = (unsigned char) (ch & 0x7F);
-			*len = 0;
-
-			while (cnt > 0) {
-				if (!asn1_octet_decode(ctx, &ch))
-					return 0;
-				*len <<= 8;
-				*len |= ch;
-				cnt--;
-			}
-		}
-	}
-
-	/* don't trust len bigger than ctx buffer */
-	if (*len > ctx->end - ctx->pointer)
-		return 0;
-
-	return 1;
-}
-
-static unsigned char
-asn1_header_decode(struct asn1_ctx *ctx,
-		   unsigned char **eoc,
-		   unsigned int *cls, unsigned int *con, unsigned int *tag)
-{
-	unsigned int def = 0;
-	unsigned int len = 0;
-
-	if (!asn1_id_decode(ctx, cls, con, tag))
-		return 0;
-
-	if (!asn1_length_decode(ctx, &def, &len))
-		return 0;
-
-	/* primitive shall be definite, indefinite shall be constructed */
-	if (*con == ASN1_PRI && !def)
-		return 0;
-
-	if (def)
-		*eoc = ctx->pointer + len;
-	else
-		*eoc = NULL;
-	return 1;
-}
-
-static unsigned char
-asn1_eoc_decode(struct asn1_ctx *ctx, unsigned char *eoc)
+int
+decode_negTokenInit(unsigned char *security_blob, int length,
+		    struct TCP_Server_Info *server)
 {
-	unsigned char ch;
-
-	if (eoc == NULL) {
-		if (!asn1_octet_decode(ctx, &ch))
-			return 0;
-
-		if (ch != 0x00) {
-			ctx->error = ASN1_ERR_DEC_EOC_MISMATCH;
-			return 0;
-		}
-
-		if (!asn1_octet_decode(ctx, &ch))
-			return 0;
-
-		if (ch != 0x00) {
-			ctx->error = ASN1_ERR_DEC_EOC_MISMATCH;
-			return 0;
-		}
-		return 1;
-	} else {
-		if (ctx->pointer != eoc) {
-			ctx->error = ASN1_ERR_DEC_LENGTH_MISMATCH;
-			return 0;
-		}
+	if (asn1_ber_decoder(&cifs_spnego_negtokeninit_decoder, server,
+			     security_blob, length) == 0)
 		return 1;
-	}
-}
-
-/* static unsigned char asn1_null_decode(struct asn1_ctx *ctx,
-				      unsigned char *eoc)
-{
-	ctx->pointer = eoc;
-	return 1;
-}
-
-static unsigned char asn1_long_decode(struct asn1_ctx *ctx,
-				      unsigned char *eoc, long *integer)
-{
-	unsigned char ch;
-	unsigned int len;
-
-	if (!asn1_octet_decode(ctx, &ch))
-		return 0;
-
-	*integer = (signed char) ch;
-	len = 1;
-
-	while (ctx->pointer < eoc) {
-		if (++len > sizeof(long)) {
-			ctx->error = ASN1_ERR_DEC_BADVALUE;
-			return 0;
-		}
-
-		if (!asn1_octet_decode(ctx, &ch))
-			return 0;
-
-		*integer <<= 8;
-		*integer |= ch;
-	}
-	return 1;
-}
-
-static unsigned char asn1_uint_decode(struct asn1_ctx *ctx,
-				      unsigned char *eoc,
-				      unsigned int *integer)
-{
-	unsigned char ch;
-	unsigned int len;
-
-	if (!asn1_octet_decode(ctx, &ch))
-		return 0;
-
-	*integer = ch;
-	if (ch == 0)
-		len = 0;
 	else
-		len = 1;
-
-	while (ctx->pointer < eoc) {
-		if (++len > sizeof(unsigned int)) {
-			ctx->error = ASN1_ERR_DEC_BADVALUE;
-			return 0;
-		}
-
-		if (!asn1_octet_decode(ctx, &ch))
-			return 0;
-
-		*integer <<= 8;
-		*integer |= ch;
-	}
-	return 1;
-}
-
-static unsigned char asn1_ulong_decode(struct asn1_ctx *ctx,
-				       unsigned char *eoc,
-				       unsigned long *integer)
-{
-	unsigned char ch;
-	unsigned int len;
-
-	if (!asn1_octet_decode(ctx, &ch))
 		return 0;
-
-	*integer = ch;
-	if (ch == 0)
-		len = 0;
-	else
-		len = 1;
-
-	while (ctx->pointer < eoc) {
-		if (++len > sizeof(unsigned long)) {
-			ctx->error = ASN1_ERR_DEC_BADVALUE;
-			return 0;
-		}
-
-		if (!asn1_octet_decode(ctx, &ch))
-			return 0;
-
-		*integer <<= 8;
-		*integer |= ch;
-	}
-	return 1;
 }
 
-static unsigned char
-asn1_octets_decode(struct asn1_ctx *ctx,
-		   unsigned char *eoc,
-		   unsigned char **octets, unsigned int *len)
+int cifs_gssapi_this_mech(void *context, size_t hdrlen,
+			  unsigned char tag, const void *value, size_t vlen)
 {
-	unsigned char *ptr;
-
-	*len = 0;
-
-	*octets = kmalloc(eoc - ctx->pointer, GFP_ATOMIC);
-	if (*octets == NULL) {
-		return 0;
-	}
-
-	ptr = *octets;
-	while (ctx->pointer < eoc) {
-		if (!asn1_octet_decode(ctx, (unsigned char *) ptr++)) {
-			kfree(*octets);
-			*octets = NULL;
-			return 0;
-		}
-		(*len)++;
-	}
-	return 1;
-} */
-
-static unsigned char
-asn1_subid_decode(struct asn1_ctx *ctx, unsigned long *subid)
-{
-	unsigned char ch;
-
-	*subid = 0;
-
-	do {
-		if (!asn1_octet_decode(ctx, &ch))
-			return 0;
-
-		*subid <<= 7;
-		*subid |= ch & 0x7F;
-	} while ((ch & 0x80) == 0x80);
-	return 1;
-}
-
-static int
-asn1_oid_decode(struct asn1_ctx *ctx,
-		unsigned char *eoc, unsigned long **oid, unsigned int *len)
-{
-	unsigned long subid;
-	unsigned int size;
-	unsigned long *optr;
-
-	size = eoc - ctx->pointer + 1;
-
-	/* first subid actually encodes first two subids */
-	if (size < 2 || size > UINT_MAX/sizeof(unsigned long))
-		return 0;
-
-	*oid = kmalloc_array(size, sizeof(unsigned long), GFP_ATOMIC);
-	if (*oid == NULL)
-		return 0;
-
-	optr = *oid;
-
-	if (!asn1_subid_decode(ctx, &subid)) {
-		kfree(*oid);
-		*oid = NULL;
-		return 0;
-	}
-
-	if (subid < 40) {
-		optr[0] = 0;
-		optr[1] = subid;
-	} else if (subid < 80) {
-		optr[0] = 1;
-		optr[1] = subid - 40;
-	} else {
-		optr[0] = 2;
-		optr[1] = subid - 80;
-	}
-
-	*len = 2;
-	optr += 2;
+	enum OID oid;
 
-	while (ctx->pointer < eoc) {
-		if (++(*len) > size) {
-			ctx->error = ASN1_ERR_DEC_BADVALUE;
-			kfree(*oid);
-			*oid = NULL;
-			return 0;
-		}
+	oid = look_up_OID(value, vlen);
+	if (oid != OID_spnego) {
+		char buf[50];
 
-		if (!asn1_subid_decode(ctx, optr++)) {
-			kfree(*oid);
-			*oid = NULL;
-			return 0;
-		}
+		sprint_oid(value, vlen, buf, sizeof(buf));
+		cifs_dbg(FYI, "Error decoding negTokenInit header: unexpected OID %s\n",
+			 buf);
+		return -EBADMSG;
 	}
-	return 1;
+	return 0;
 }
 
-static int
-compare_oid(unsigned long *oid1, unsigned int oid1len,
-	    unsigned long *oid2, unsigned int oid2len)
+int cifs_neg_token_init_mech_type(void *context, size_t hdrlen,
+				  unsigned char tag,
+				  const void *value, size_t vlen)
 {
-	unsigned int i;
+	struct TCP_Server_Info *server = context;
+	enum OID oid;
 
-	if (oid1len != oid2len)
-		return 0;
+	oid = look_up_OID(value, vlen);
+	if (oid == OID_mskrb5)
+		server->sec_mskerberos = true;
+	else if (oid == OID_krb5u2u)
+		server->sec_kerberosu2u = true;
+	else if (oid == OID_krb5)
+		server->sec_kerberos = true;
+	else if (oid == OID_ntlmssp)
+		server->sec_ntlmssp = true;
 	else {
-		for (i = 0; i < oid1len; i++) {
-			if (oid1[i] != oid2[i])
-				return 0;
-		}
-		return 1;
-	}
-}
-
-	/* BB check for endian conversion issues here */
-
-int
-decode_negTokenInit(unsigned char *security_blob, int length,
-		    struct TCP_Server_Info *server)
-{
-	struct asn1_ctx ctx;
-	unsigned char *end;
-	unsigned char *sequence_end;
-	unsigned long *oid = NULL;
-	unsigned int cls, con, tag, oidlen, rc;
-
-	/* cifs_dump_mem(" Received SecBlob ", security_blob, length); */
-
-	asn1_open(&ctx, security_blob, length);
+		char buf[50];
 
-	/* GSSAPI header */
-	if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
-		cifs_dbg(FYI, "Error decoding negTokenInit header\n");
-		return 0;
-	} else if ((cls != ASN1_APL) || (con != ASN1_CON)
-		   || (tag != ASN1_EOC)) {
-		cifs_dbg(FYI, "cls = %d con = %d tag = %d\n", cls, con, tag);
-		return 0;
+		sprint_oid(value, vlen, buf, sizeof(buf));
+		cifs_dbg(FYI, "Decoding negTokenInit: unsupported OID %s\n",
+			 buf);
 	}
-
-	/* Check for SPNEGO OID -- remember to free obj->oid */
-	rc = asn1_header_decode(&ctx, &end, &cls, &con, &tag);
-	if (rc) {
-		if ((tag == ASN1_OJI) && (con == ASN1_PRI) &&
-		    (cls == ASN1_UNI)) {
-			rc = asn1_oid_decode(&ctx, end, &oid, &oidlen);
-			if (rc) {
-				rc = compare_oid(oid, oidlen, SPNEGO_OID,
-						 SPNEGO_OID_LEN);
-				kfree(oid);
-			}
-		} else
-			rc = 0;
-	}
-
-	/* SPNEGO OID not present or garbled -- bail out */
-	if (!rc) {
-		cifs_dbg(FYI, "Error decoding negTokenInit header\n");
-		return 0;
-	}
-
-	/* SPNEGO */
-	if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
-		cifs_dbg(FYI, "Error decoding negTokenInit\n");
-		return 0;
-	} else if ((cls != ASN1_CTX) || (con != ASN1_CON)
-		   || (tag != ASN1_EOC)) {
-		cifs_dbg(FYI, "cls = %d con = %d tag = %d end = %p exit 0\n",
-			 cls, con, tag, end);
-		return 0;
-	}
-
-	/* negTokenInit */
-	if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
-		cifs_dbg(FYI, "Error decoding negTokenInit\n");
-		return 0;
-	} else if ((cls != ASN1_UNI) || (con != ASN1_CON)
-		   || (tag != ASN1_SEQ)) {
-		cifs_dbg(FYI, "cls = %d con = %d tag = %d end = %p exit 1\n",
-			 cls, con, tag, end);
-		return 0;
-	}
-
-	/* sequence */
-	if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
-		cifs_dbg(FYI, "Error decoding 2nd part of negTokenInit\n");
-		return 0;
-	} else if ((cls != ASN1_CTX) || (con != ASN1_CON)
-		   || (tag != ASN1_EOC)) {
-		cifs_dbg(FYI, "cls = %d con = %d tag = %d end = %p exit 0\n",
-			 cls, con, tag, end);
-		return 0;
-	}
-
-	/* sequence of */
-	if (asn1_header_decode
-	    (&ctx, &sequence_end, &cls, &con, &tag) == 0) {
-		cifs_dbg(FYI, "Error decoding 2nd part of negTokenInit\n");
-		return 0;
-	} else if ((cls != ASN1_UNI) || (con != ASN1_CON)
-		   || (tag != ASN1_SEQ)) {
-		cifs_dbg(FYI, "cls = %d con = %d tag = %d sequence_end = %p exit 1\n",
-			 cls, con, tag, sequence_end);
-		return 0;
-	}
-
-	/* list of security mechanisms */
-	while (!asn1_eoc_decode(&ctx, sequence_end)) {
-		rc = asn1_header_decode(&ctx, &end, &cls, &con, &tag);
-		if (!rc) {
-			cifs_dbg(FYI, "Error decoding negTokenInit hdr exit2\n");
-			return 0;
-		}
-		if ((tag == ASN1_OJI) && (con == ASN1_PRI)) {
-			if (asn1_oid_decode(&ctx, end, &oid, &oidlen)) {
-
-				cifs_dbg(FYI, "OID len = %d oid = 0x%lx 0x%lx 0x%lx 0x%lx\n",
-					 oidlen, *oid, *(oid + 1), *(oid + 2),
-					 *(oid + 3));
-
-				if (compare_oid(oid, oidlen, MSKRB5_OID,
-						MSKRB5_OID_LEN))
-					server->sec_mskerberos = true;
-				else if (compare_oid(oid, oidlen, KRB5U2U_OID,
-						     KRB5U2U_OID_LEN))
-					server->sec_kerberosu2u = true;
-				else if (compare_oid(oid, oidlen, KRB5_OID,
-						     KRB5_OID_LEN))
-					server->sec_kerberos = true;
-				else if (compare_oid(oid, oidlen, NTLMSSP_OID,
-						     NTLMSSP_OID_LEN))
-					server->sec_ntlmssp = true;
-
-				kfree(oid);
-			}
-		} else {
-			cifs_dbg(FYI, "Should be an oid what is going on?\n");
-		}
-	}
-
-	/*
-	 * We currently ignore anything at the end of the SPNEGO blob after
-	 * the mechTypes have been parsed, since none of that info is
-	 * used at the moment.
-	 */
-	return 1;
+	return 0;
 }
diff --git a/fs/cifs/cache.c b/fs/cifs/cache.c
index 488fe0ffc1ef..8a3b30ec860c 100644
--- a/fs/cifs/cache.c
+++ b/fs/cifs/cache.c
@@ -1,22 +1,10 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/cache.c - CIFS filesystem cache index structure definitions
  *
  *   Copyright (c) 2010 Novell, Inc.
  *   Authors(s): Suresh Jayaraman (sjayaraman@suse.de>
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 #include "fscache.h"
 #include "cifs_debug.h"
diff --git a/fs/cifs/cifs_debug.c b/fs/cifs/cifs_debug.c
index 68e8e5b27841..8857ac7e7a14 100644
--- a/fs/cifs/cifs_debug.c
+++ b/fs/cifs/cifs_debug.c
@@ -50,7 +50,6 @@ void cifs_dump_detail(void *buf, struct TCP_Server_Info *server)
 void cifs_dump_mids(struct TCP_Server_Info *server)
 {
 #ifdef CONFIG_CIFS_DEBUG2
-	struct list_head *tmp;
 	struct mid_q_entry *mid_entry;
 
 	if (server == NULL)
@@ -58,8 +57,7 @@ void cifs_dump_mids(struct TCP_Server_Info *server)
 
 	cifs_dbg(VFS, "Dump pending requests:\n");
 	spin_lock(&GlobalMid_Lock);
-	list_for_each(tmp, &server->pending_mid_q) {
-		mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
+	list_for_each_entry(mid_entry, &server->pending_mid_q, qhead) {
 		cifs_dbg(VFS, "State: %d Cmd: %d Pid: %d Cbdata: %p Mid %llu\n",
 			 mid_entry->mid_state,
 			 le16_to_cpu(mid_entry->command),
@@ -168,7 +166,7 @@ cifs_dump_iface(struct seq_file *m, struct cifs_server_iface *iface)
 
 static int cifs_debug_files_proc_show(struct seq_file *m, void *v)
 {
-	struct list_head *stmp, *tmp, *tmp1, *tmp2;
+	struct list_head *tmp, *tmp1, *tmp2;
 	struct TCP_Server_Info *server;
 	struct cifs_ses *ses;
 	struct cifs_tcon *tcon;
@@ -183,9 +181,7 @@ static int cifs_debug_files_proc_show(struct seq_file *m, void *v)
 	seq_printf(m, " <filename>\n");
 #endif /* CIFS_DEBUG2 */
 	spin_lock(&cifs_tcp_ses_lock);
-	list_for_each(stmp, &cifs_tcp_ses_list) {
-		server = list_entry(stmp, struct TCP_Server_Info,
-				    tcp_ses_list);
+	list_for_each_entry(server, &cifs_tcp_ses_list, tcp_ses_list) {
 		list_for_each(tmp, &server->smb_ses_list) {
 			ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
 			list_for_each(tmp1, &ses->tcon_list) {
@@ -220,7 +216,7 @@ static int cifs_debug_files_proc_show(struct seq_file *m, void *v)
 
 static int cifs_debug_data_proc_show(struct seq_file *m, void *v)
 {
-	struct list_head *tmp1, *tmp2, *tmp3;
+	struct list_head *tmp2, *tmp3;
 	struct mid_q_entry *mid_entry;
 	struct TCP_Server_Info *server;
 	struct cifs_ses *ses;
@@ -278,11 +274,7 @@ static int cifs_debug_data_proc_show(struct seq_file *m, void *v)
 
 	c = 0;
 	spin_lock(&cifs_tcp_ses_lock);
-	list_for_each(tmp1, &cifs_tcp_ses_list) {
-		server = list_entry(tmp1, struct TCP_Server_Info,
-				    tcp_ses_list);
-
-		/* channel info will be printed as a part of sessions below */
+	list_for_each_entry(server, &cifs_tcp_ses_list, tcp_ses_list) {
 		if (server->is_channel)
 			continue;
 
@@ -563,7 +555,7 @@ static int cifs_stats_proc_show(struct seq_file *m, void *v)
 #ifdef CONFIG_CIFS_STATS2
 	int j;
 #endif /* STATS2 */
-	struct list_head *tmp1, *tmp2, *tmp3;
+	struct list_head *tmp2, *tmp3;
 	struct TCP_Server_Info *server;
 	struct cifs_ses *ses;
 	struct cifs_tcon *tcon;
@@ -594,9 +586,7 @@ static int cifs_stats_proc_show(struct seq_file *m, void *v)
 
 	i = 0;
 	spin_lock(&cifs_tcp_ses_lock);
-	list_for_each(tmp1, &cifs_tcp_ses_list) {
-		server = list_entry(tmp1, struct TCP_Server_Info,
-				    tcp_ses_list);
+	list_for_each_entry(server, &cifs_tcp_ses_list, tcp_ses_list) {
 		seq_printf(m, "\nMax requests in flight: %d", server->max_in_flight);
 #ifdef CONFIG_CIFS_STATS2
 		seq_puts(m, "\nTotal time spent processing by command. Time ");
diff --git a/fs/cifs/cifs_debug.h b/fs/cifs/cifs_debug.h
index 5e66dab712d0..ee4ea2b60c0f 100644
--- a/fs/cifs/cifs_debug.h
+++ b/fs/cifs/cifs_debug.h
@@ -3,7 +3,7 @@
  *
  *   Copyright (c) International Business Machines  Corp., 2000,2002
  *   Modified by Steve French (sfrench@us.ibm.com)
-*/
+ */
 
 #ifndef _H_CIFS_DEBUG
 #define _H_CIFS_DEBUG
diff --git a/fs/cifs/cifs_dfs_ref.c b/fs/cifs/cifs_dfs_ref.c
index c87c37cf2914..ec57cdb1590f 100644
--- a/fs/cifs/cifs_dfs_ref.c
+++ b/fs/cifs/cifs_dfs_ref.c
@@ -125,7 +125,7 @@ cifs_build_devname(char *nodename, const char *prepath)
  * @sb_mountdata:	parent/root DFS mount options (template)
  * @fullpath:		full path in UNC format
  * @ref:		optional server's referral
- *
+ * @devname:		return the built cifs device name if passed pointer not NULL
  * creates mount options for submount based on template options sb_mountdata
  * and replacing unc,ip,prefixpath options with ones we've got form ref_unc.
  *
diff --git a/fs/cifs/cifs_fs_sb.h b/fs/cifs/cifs_fs_sb.h
index 9c45b3a82ad9..4fd788586399 100644
--- a/fs/cifs/cifs_fs_sb.h
+++ b/fs/cifs/cifs_fs_sb.h
@@ -1,19 +1,10 @@
+/* SPDX-License-Identifier: LGPL-2.1 */
 /*
  *   fs/cifs/cifs_fs_sb.h
  *
  *   Copyright (c) International Business Machines  Corp., 2002,2004
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
  */
 #include <linux/rbtree.h>
 
@@ -72,11 +63,12 @@ struct cifs_sb_info {
 	char *prepath;
 
 	/*
-	 * Path initially provided by the mount call. We might connect
-	 * to something different via DFS but we want to keep it to do
-	 * failover properly.
+	 * Canonical DFS path initially provided by the mount call. We might connect to something
+	 * different via DFS but we want to keep it to do failover properly.
 	 */
 	char *origin_fullpath; /* \\HOST\SHARE\[OPTIONAL PATH] */
+	/* randomly generated 128-bit number for indexing dfs mount groups in referral cache */
+	uuid_t dfs_mount_id;
 	/*
 	 * Indicate whether serverino option was turned off later
 	 * (cifs_autodisable_serverino) in order to match new mounts.
diff --git a/fs/cifs/cifs_ioctl.h b/fs/cifs/cifs_ioctl.h
index 37fc7d6ac457..ef723be358af 100644
--- a/fs/cifs/cifs_ioctl.h
+++ b/fs/cifs/cifs_ioctl.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: LGPL-2.1 */
 /*
  *   fs/cifs/cifs_ioctl.h
  *
@@ -5,16 +6,6 @@
  *
  *   Copyright (c) 2015 Steve French <steve.french@primarydata.com>
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
  */
 
 struct smb_mnt_fs_info {
diff --git a/fs/cifs/cifs_spnego.c b/fs/cifs/cifs_spnego.c
index 7b9b876b513b..8fa26a8530f8 100644
--- a/fs/cifs/cifs_spnego.c
+++ b/fs/cifs/cifs_spnego.c
@@ -1,22 +1,10 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/cifs_spnego.c -- SPNEGO upcall management for CIFS
  *
  *   Copyright (c) 2007 Red Hat, Inc.
  *   Author(s): Jeff Layton (jlayton@redhat.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
 #include <linux/list.h>
diff --git a/fs/cifs/cifs_spnego.h b/fs/cifs/cifs_spnego.h
index 31bef9ee078b..31387d0ea32e 100644
--- a/fs/cifs/cifs_spnego.h
+++ b/fs/cifs/cifs_spnego.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: LGPL-2.1 */
 /*
  *   fs/cifs/cifs_spnego.h -- SPNEGO upcall management for CIFS
  *
@@ -5,19 +6,6 @@
  *   Author(s): Jeff Layton (jlayton@redhat.com)
  *              Steve French (sfrench@us.ibm.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
 #ifndef _CIFS_SPNEGO_H
diff --git a/fs/cifs/cifs_spnego_negtokeninit.asn1 b/fs/cifs/cifs_spnego_negtokeninit.asn1
new file mode 100644
index 000000000000..181c083887d5
--- /dev/null
+++ b/fs/cifs/cifs_spnego_negtokeninit.asn1
@@ -0,0 +1,40 @@
+GSSAPI ::=
+	[APPLICATION 0] IMPLICIT SEQUENCE {
+		thisMech
+			OBJECT IDENTIFIER ({cifs_gssapi_this_mech}),
+		negotiationToken
+			NegotiationToken
+	}
+
+MechType ::= OBJECT IDENTIFIER ({cifs_neg_token_init_mech_type})
+
+MechTypeList ::= SEQUENCE OF MechType
+
+NegHints ::= SEQUENCE {
+	hintName
+		[0] GeneralString OPTIONAL,
+	hintAddress
+		[1] OCTET STRING OPTIONAL
+	}
+
+NegTokenInit2 ::=
+	SEQUENCE {
+		mechTypes
+			[0] MechTypeList OPTIONAL,
+		reqFlags
+			[1] BIT STRING OPTIONAL,
+		mechToken
+			[2] OCTET STRING OPTIONAL,
+		negHints
+			[3] NegHints OPTIONAL,
+		mechListMIC
+			[3] OCTET STRING OPTIONAL
+	}
+
+NegotiationToken ::=
+	CHOICE {
+		negTokenInit
+			[0] NegTokenInit2,
+		negTokenTarg
+			[1] ANY
+	}
diff --git a/fs/cifs/cifs_swn.c b/fs/cifs/cifs_swn.c
index d829b8bf833e..93b47818c6c2 100644
--- a/fs/cifs/cifs_swn.c
+++ b/fs/cifs/cifs_swn.c
@@ -447,15 +447,13 @@ static int cifs_swn_store_swn_addr(const struct sockaddr_storage *new,
 				   const struct sockaddr_storage *old,
 				   struct sockaddr_storage *dst)
 {
-	__be16 port;
+	__be16 port = cpu_to_be16(CIFS_PORT);
 
 	if (old->ss_family == AF_INET) {
 		struct sockaddr_in *ipv4 = (struct sockaddr_in *)old;
 
 		port = ipv4->sin_port;
-	}
-
-	if (old->ss_family == AF_INET6) {
+	} else if (old->ss_family == AF_INET6) {
 		struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)old;
 
 		port = ipv6->sin6_port;
@@ -465,9 +463,7 @@ static int cifs_swn_store_swn_addr(const struct sockaddr_storage *new,
 		struct sockaddr_in *ipv4 = (struct sockaddr_in *)new;
 
 		ipv4->sin_port = port;
-	}
-
-	if (new->ss_family == AF_INET6) {
+	} else if (new->ss_family == AF_INET6) {
 		struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)new;
 
 		ipv6->sin6_port = port;
diff --git a/fs/cifs/cifsacl.c b/fs/cifs/cifsacl.c
index 784407f9280f..388eb536cff1 100644
--- a/fs/cifs/cifsacl.c
+++ b/fs/cifs/cifsacl.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/cifsacl.c
  *
@@ -6,19 +7,6 @@
  *
  *   Contains the routines for mapping CIFS/NTFS ACLs
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
 #include <linux/fs.h>
@@ -409,7 +397,6 @@ try_upcall_to_get_id:
 	saved_cred = override_creds(root_cred);
 	sidkey = request_key(&cifs_idmap_key_type, sidstr, "");
 	if (IS_ERR(sidkey)) {
-		rc = -EINVAL;
 		cifs_dbg(FYI, "%s: Can't map SID %s to a %cid\n",
 			 __func__, sidstr, sidtype == SIDOWNER ? 'u' : 'g');
 		goto out_revert_creds;
@@ -422,7 +409,6 @@ try_upcall_to_get_id:
 	 */
 	BUILD_BUG_ON(sizeof(uid_t) != sizeof(gid_t));
 	if (sidkey->datalen != sizeof(uid_t)) {
-		rc = -EIO;
 		cifs_dbg(FYI, "%s: Downcall contained malformed key (datalen=%hu)\n",
 			 __func__, sidkey->datalen);
 		key_invalidate(sidkey);
@@ -1308,7 +1294,7 @@ static int build_sec_desc(struct cifs_ntsd *pntsd, struct cifs_ntsd *pnntsd,
 		ndacl_ptr = (struct cifs_acl *)((char *)pnntsd + ndacloffset);
 		ndacl_ptr->revision =
 			dacloffset ? dacl_ptr->revision : cpu_to_le16(ACL_REVISION);
-		ndacl_ptr->num_aces = dacl_ptr->num_aces;
+		ndacl_ptr->num_aces = dacl_ptr ? dacl_ptr->num_aces : 0;
 
 		if (uid_valid(uid)) { /* chown */
 			uid_t id;
diff --git a/fs/cifs/cifsacl.h b/fs/cifs/cifsacl.h
index d9e704979d99..f8292bcf8594 100644
--- a/fs/cifs/cifsacl.h
+++ b/fs/cifs/cifsacl.h
@@ -1,28 +1,15 @@
+/* SPDX-License-Identifier: LGPL-2.1 */
 /*
  *   fs/cifs/cifsacl.h
  *
  *   Copyright (c) International Business Machines  Corp., 2007
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
 #ifndef _CIFSACL_H
 #define _CIFSACL_H
 
-
 #define NUM_AUTHS (6)	/* number of authority fields */
 #define SID_MAX_SUB_AUTHORITIES (15) /* max number of sub authority fields */
 
diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c
index b8f1ff9a83f3..ecf15d845dbd 100644
--- a/fs/cifs/cifsencrypt.c
+++ b/fs/cifs/cifsencrypt.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/cifsencrypt.c
  *
@@ -7,19 +8,6 @@
  *   Copyright (C) International Business Machines  Corp., 2005,2013
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
 #include <linux/fs.h>
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 2ffcb29d5c8f..9fb874dd8d24 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/cifsfs.c
  *
@@ -6,19 +7,6 @@
  *
  *   Common Internet FileSystem (CIFS) client
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
 /* Note that BB means BUGBUG (ie something to fix eventually) */
diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h
index 6beddb108ba0..177f3e7ab86d 100644
--- a/fs/cifs/cifsfs.h
+++ b/fs/cifs/cifsfs.h
@@ -1,22 +1,10 @@
+/* SPDX-License-Identifier: LGPL-2.1 */
 /*
  *   fs/cifs/cifsfs.h
  *
  *   Copyright (c) International Business Machines  Corp., 2002, 2007
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
 #ifndef _CIFSFS_H
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 8488d7024462..3100f8b66e60 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: LGPL-2.1 */
 /*
  *   fs/cifs/cifsglob.h
  *
@@ -5,16 +6,6 @@
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *              Jeremy Allison (jra@samba.org)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
  */
 #ifndef _CIFS_GLOB_H
 #define _CIFS_GLOB_H
@@ -630,7 +621,7 @@ struct TCP_Server_Info {
 	/* SMB_COM_WRITE_RAW or SMB_COM_READ_RAW. */
 	unsigned int capabilities; /* selective disabling of caps by smb sess */
 	int timeAdj;  /* Adjust for difference in server time zone in sec */
-	__u64 CurrentMid;         /* multiplex id - rotating counter */
+	__u64 CurrentMid;         /* multiplex id - rotating counter, protected by GlobalMid_Lock */
 	char cryptkey[CIFS_CRYPTO_KEY_SIZE]; /* used by ntlm, ntlmv2 etc */
 	/* 16th byte of RFC1001 workstation name is always null */
 	char workstation_RFC1001_name[RFC1001_NAME_LEN_WITH_NULL];
@@ -896,7 +887,7 @@ struct cifs_ses {
 	struct mutex session_mutex;
 	struct TCP_Server_Info *server;	/* pointer to server info */
 	int ses_count;		/* reference counter */
-	enum statusEnum status;
+	enum statusEnum status;  /* updates protected by GlobalMid_Lock */
 	unsigned overrideSecFlg;  /* if non-zero override global sec flags */
 	char *serverOS;		/* name of operating system underlying server */
 	char *serverNOS;	/* name of network operating system of server */
@@ -1093,8 +1084,7 @@ struct cifs_tcon {
 	struct cached_fid crfid; /* Cached root fid */
 	/* BB add field for back pointer to sb struct(s)? */
 #ifdef CONFIG_CIFS_DFS_UPCALL
-	char *dfs_path;
-	int remap:2;
+	char *dfs_path; /* canonical DFS path */
 	struct list_head ulist; /* cache update list */
 #endif
 };
@@ -1795,6 +1785,8 @@ require use of the stronger protocol */
  *	list operations on pending_mid_q and oplockQ
  *      updates to XID counters, multiplex id  and SMB sequence numbers
  *      list operations on global DnotifyReqList
+ *      updates to ses->status
+ *      updates to server->CurrentMid
  *  tcp_ses_lock protects:
  *	list operations on tcp and SMB session lists
  *  tcon->open_file_lock protects the list of open files hanging off the tcon
diff --git a/fs/cifs/cifspdu.h b/fs/cifs/cifspdu.h
index 554d64fe171e..0923f72d27e9 100644
--- a/fs/cifs/cifspdu.h
+++ b/fs/cifs/cifspdu.h
@@ -1,22 +1,10 @@
+/* SPDX-License-Identifier: LGPL-2.1 */
 /*
  *   fs/cifs/cifspdu.h
  *
  *   Copyright (c) International Business Machines  Corp., 2002,2009
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
 #ifndef _CIFSPDU_H
diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index d30cba44ba29..e0def0f0714b 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -1,22 +1,10 @@
+/* SPDX-License-Identifier: LGPL-2.1 */
 /*
  *   fs/cifs/cifsproto.h
  *
  *   Copyright (c) International Business Machines  Corp., 2002,2008
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 #ifndef _CIFSPROTO_H
 #define _CIFSPROTO_H
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index 41f74163cc1c..58ebec4d4413 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/cifssmb.c
  *
@@ -6,19 +7,6 @@
  *
  *   Contains the routines for constructing the SMB PDUs themselves
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
  /* SMB/CIFS PDU handling routines here - except for leftovers in connect.c   */
@@ -1220,7 +1208,7 @@ SMBLegacyOpen(const unsigned int xid, struct cifs_tcon *tcon,
 	    int *pOplock, FILE_ALL_INFO *pfile_info,
 	    const struct nls_table *nls_codepage, int remap)
 {
-	int rc = -EACCES;
+	int rc;
 	OPENX_REQ *pSMB = NULL;
 	OPENX_RSP *pSMBr = NULL;
 	int bytes_returned;
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 495c395f9def..5d269f583dac 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -1,22 +1,10 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/connect.c
  *
  *   Copyright (C) International Business Machines  Corp., 2002,2011
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 #include <linux/fs.h>
 #include <linux/net.h>
@@ -368,13 +356,7 @@ cifs_reconnect(struct TCP_Server_Info *server)
 			cifs_server_dbg(VFS, "%s: failed to update DFS target hint: rc = %d\n",
 				 __func__, rc);
 		}
-		rc = dfs_cache_update_vol(cifs_sb->origin_fullpath, server);
-		if (rc) {
-			cifs_server_dbg(VFS, "%s: failed to update vol info in DFS cache: rc = %d\n",
-				 __func__, rc);
-		}
 		dfs_cache_free_tgts(&tgt_list);
-
 	}
 
 	cifs_put_tcp_super(sb);
@@ -1557,29 +1539,25 @@ out:
 /**
  * cifs_free_ipc - helper to release the session IPC tcon
  *
- * Needs to be called everytime a session is destroyed
+ * Needs to be called everytime a session is destroyed.
+ *
+ * On session close, the IPC is closed and the server must release all tcons of the session.
+ * No need to send a tree disconnect here.
+ *
+ * Besides, it will make the server to not close durable and resilient files on session close, as
+ * specified in MS-SMB2 3.3.5.6 Receiving an SMB2 LOGOFF Request.
  */
 static int
 cifs_free_ipc(struct cifs_ses *ses)
 {
-	int rc = 0, xid;
 	struct cifs_tcon *tcon = ses->tcon_ipc;
 
 	if (tcon == NULL)
 		return 0;
 
-	if (ses->server->ops->tree_disconnect) {
-		xid = get_xid();
-		rc = ses->server->ops->tree_disconnect(xid, tcon);
-		free_xid(xid);
-	}
-
-	if (rc)
-		cifs_dbg(FYI, "failed to disconnect IPC tcon (rc=%d)\n", rc);
-
 	tconInfoFree(tcon);
 	ses->tcon_ipc = NULL;
-	return rc;
+	return 0;
 }
 
 static struct cifs_ses *
@@ -1605,7 +1583,6 @@ void cifs_put_smb_ses(struct cifs_ses *ses)
 {
 	unsigned int rc, xid;
 	struct TCP_Server_Info *server = ses->server;
-
 	cifs_dbg(FYI, "%s: ses_count=%d\n", __func__, ses->ses_count);
 
 	spin_lock(&cifs_tcp_ses_lock);
@@ -1613,13 +1590,20 @@ void cifs_put_smb_ses(struct cifs_ses *ses)
 		spin_unlock(&cifs_tcp_ses_lock);
 		return;
 	}
+
+	cifs_dbg(FYI, "%s: ses_count=%d\n", __func__, ses->ses_count);
+	cifs_dbg(FYI, "%s: ses ipc: %s\n", __func__, ses->tcon_ipc ? ses->tcon_ipc->treeName : "NONE");
+
 	if (--ses->ses_count > 0) {
 		spin_unlock(&cifs_tcp_ses_lock);
 		return;
 	}
+	spin_unlock(&cifs_tcp_ses_lock);
+
+	spin_lock(&GlobalMid_Lock);
 	if (ses->status == CifsGood)
 		ses->status = CifsExiting;
-	spin_unlock(&cifs_tcp_ses_lock);
+	spin_unlock(&GlobalMid_Lock);
 
 	cifs_free_ipc(ses);
 
@@ -1951,10 +1935,7 @@ cifs_find_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
 	spin_lock(&cifs_tcp_ses_lock);
 	list_for_each(tmp, &ses->tcon_list) {
 		tcon = list_entry(tmp, struct cifs_tcon, tcon_list);
-#ifdef CONFIG_CIFS_DFS_UPCALL
-		if (tcon->dfs_path)
-			continue;
-#endif
+
 		if (!match_tcon(tcon, ctx))
 			continue;
 		++tcon->tc_count;
@@ -3017,9 +2998,8 @@ expand_dfs_referral(const unsigned int xid, struct cifs_ses *ses,
 	return rc;
 }
 
-static inline int get_next_dfs_tgt(const char *path,
-				   struct dfs_cache_tgt_list *tgt_list,
-				   struct dfs_cache_tgt_iterator **tgt_it)
+static int get_next_dfs_tgt(struct dfs_cache_tgt_list *tgt_list,
+			    struct dfs_cache_tgt_iterator **tgt_it)
 {
 	if (!*tgt_it)
 		*tgt_it = dfs_cache_get_tgt_iterator(tgt_list);
@@ -3059,6 +3039,7 @@ static int do_dfs_failover(const char *path, const char *full_path, struct cifs_
 			   struct cifs_ses **ses, struct cifs_tcon **tcon)
 {
 	int rc;
+	char *npath = NULL;
 	struct dfs_cache_tgt_list tgt_list = {0};
 	struct dfs_cache_tgt_iterator *tgt_it = NULL;
 	struct smb3_fs_context tmp_ctx = {NULL};
@@ -3066,11 +3047,15 @@ static int do_dfs_failover(const char *path, const char *full_path, struct cifs_
 	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_DFS)
 		return -EOPNOTSUPP;
 
-	cifs_dbg(FYI, "%s: path=%s full_path=%s\n", __func__, path, full_path);
+	npath = dfs_cache_canonical_path(path, cifs_sb->local_nls, cifs_remap(cifs_sb));
+	if (IS_ERR(npath))
+		return PTR_ERR(npath);
+
+	cifs_dbg(FYI, "%s: path=%s full_path=%s\n", __func__, npath, full_path);
 
-	rc = dfs_cache_noreq_find(path, NULL, &tgt_list);
+	rc = dfs_cache_noreq_find(npath, NULL, &tgt_list);
 	if (rc)
-		return rc;
+		goto out;
 	/*
 	 * We use a 'tmp_ctx' here because we need pass it down to the mount_{get,put} functions to
 	 * test connection against new DFS targets.
@@ -3084,11 +3069,11 @@ static int do_dfs_failover(const char *path, const char *full_path, struct cifs_
 		char *fake_devname = NULL, *mdata = NULL;
 
 		/* Get next DFS target server - if any */
-		rc = get_next_dfs_tgt(path, &tgt_list, &tgt_it);
+		rc = get_next_dfs_tgt(&tgt_list, &tgt_it);
 		if (rc)
 			break;
 
-		rc = dfs_cache_get_tgt_referral(path, tgt_it, &ref);
+		rc = dfs_cache_get_tgt_referral(npath, tgt_it, &ref);
 		if (rc)
 			break;
 
@@ -3137,6 +3122,7 @@ static int do_dfs_failover(const char *path, const char *full_path, struct cifs_
 	}
 
 out:
+	kfree(npath);
 	smb3_cleanup_fs_context_contents(&tmp_ctx);
 	dfs_cache_free_tgts(&tgt_list);
 	return rc;
@@ -3288,25 +3274,18 @@ static int is_path_remote(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *
 }
 
 #ifdef CONFIG_CIFS_DFS_UPCALL
-static void set_root_ses(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
+static void set_root_ses(struct cifs_sb_info *cifs_sb, const uuid_t *mount_id, struct cifs_ses *ses,
 			 struct cifs_ses **root_ses)
 {
 	if (ses) {
 		spin_lock(&cifs_tcp_ses_lock);
 		ses->ses_count++;
-		if (ses->tcon_ipc)
-			ses->tcon_ipc->remap = cifs_remap(cifs_sb);
 		spin_unlock(&cifs_tcp_ses_lock);
+		dfs_cache_add_refsrv_session(mount_id, ses);
 	}
 	*root_ses = ses;
 }
 
-static void put_root_ses(struct cifs_ses *ses)
-{
-	if (ses)
-		cifs_put_smb_ses(ses);
-}
-
 /* Set up next dfs prefix path in @dfs_path */
 static int next_dfs_prepath(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx,
 			    const unsigned int xid, struct TCP_Server_Info *server,
@@ -3352,17 +3331,25 @@ out:
 }
 
 /* Check if resolved targets can handle any DFS referrals */
-static int is_referral_server(const char *ref_path, struct cifs_tcon *tcon, bool *ref_server)
+static int is_referral_server(const char *ref_path, struct cifs_sb_info *cifs_sb,
+			      struct cifs_tcon *tcon, bool *ref_server)
 {
 	int rc;
 	struct dfs_info3_param ref = {0};
 
+	cifs_dbg(FYI, "%s: ref_path=%s\n", __func__, ref_path);
+
 	if (is_tcon_dfs(tcon)) {
 		*ref_server = true;
 	} else {
-		cifs_dbg(FYI, "%s: ref_path=%s\n", __func__, ref_path);
+		char *npath;
 
-		rc = dfs_cache_noreq_find(ref_path, &ref, NULL);
+		npath = dfs_cache_canonical_path(ref_path, cifs_sb->local_nls, cifs_remap(cifs_sb));
+		if (IS_ERR(npath))
+			return PTR_ERR(npath);
+
+		rc = dfs_cache_noreq_find(npath, &ref, NULL);
+		kfree(npath);
 		if (rc) {
 			cifs_dbg(VFS, "%s: dfs_cache_noreq_find: failed (rc=%d)\n", __func__, rc);
 			return rc;
@@ -3386,9 +3373,9 @@ int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
 	struct cifs_ses *ses = NULL, *root_ses = NULL;
 	struct cifs_tcon *tcon = NULL;
 	int count = 0;
+	uuid_t mount_id = {0};
 	char *ref_path = NULL, *full_path = NULL;
 	char *oldmnt = NULL;
-	char *mntdata = NULL;
 	bool ref_server = false;
 
 	rc = mount_get_conns(ctx, cifs_sb, &xid, &server, &ses, &tcon);
@@ -3411,12 +3398,9 @@ int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
 		if (rc != -EREMOTE)
 			goto error;
 	}
-	/* Save mount options */
-	mntdata = kstrdup(cifs_sb->ctx->mount_options, GFP_KERNEL);
-	if (!mntdata) {
-		rc = -ENOMEM;
-		goto error;
-	}
+
+	ctx->nosharesock = true;
+
 	/* Get path of DFS root */
 	ref_path = build_unc_path_to_root(ctx, cifs_sb, false);
 	if (IS_ERR(ref_path)) {
@@ -3425,7 +3409,8 @@ int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
 		goto error;
 	}
 
-	set_root_ses(cifs_sb, ses, &root_ses);
+	uuid_gen(&mount_id);
+	set_root_ses(cifs_sb, &mount_id, ses, &root_ses);
 	do {
 		/* Save full path of last DFS path we used to resolve final target server */
 		kfree(full_path);
@@ -3456,13 +3441,11 @@ int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
 			continue;
 
 		/* Make sure that requests go through new root servers */
-		rc = is_referral_server(ref_path + 1, tcon, &ref_server);
+		rc = is_referral_server(ref_path + 1, cifs_sb, tcon, &ref_server);
 		if (rc)
 			break;
-		if (ref_server) {
-			put_root_ses(root_ses);
-			set_root_ses(cifs_sb, ses, &root_ses);
-		}
+		if (ref_server)
+			set_root_ses(cifs_sb, &mount_id, ses, &root_ses);
 
 		/* Get next dfs path and then continue chasing them if -EREMOTE */
 		rc = next_dfs_prepath(cifs_sb, ctx, xid, server, tcon, &ref_path);
@@ -3471,12 +3454,10 @@ int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
 			rc = -ELOOP;
 	} while (rc == -EREMOTE);
 
-	if (rc)
+	if (rc || !tcon)
 		goto error;
-	put_root_ses(root_ses);
-	root_ses = NULL;
+
 	kfree(ref_path);
-	ref_path = NULL;
 	/*
 	 * Store DFS full path in both superblock and tree connect structures.
 	 *
@@ -3485,21 +3466,27 @@ int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
 	 * links, the prefix path is included in both and may be changed during reconnect.  See
 	 * cifs_tree_connect().
 	 */
-	cifs_sb->origin_fullpath = kstrdup(full_path, GFP_KERNEL);
-	if (!cifs_sb->origin_fullpath) {
+	ref_path = dfs_cache_canonical_path(full_path, cifs_sb->local_nls, cifs_remap(cifs_sb));
+	kfree(full_path);
+	full_path = NULL;
+
+	if (IS_ERR(ref_path)) {
+		rc = PTR_ERR(ref_path);
+		ref_path = NULL;
+		goto error;
+	}
+	cifs_sb->origin_fullpath = ref_path;
+
+	ref_path = kstrdup(cifs_sb->origin_fullpath, GFP_KERNEL);
+	if (!ref_path) {
 		rc = -ENOMEM;
 		goto error;
 	}
 	spin_lock(&cifs_tcp_ses_lock);
-	tcon->dfs_path = full_path;
-	full_path = NULL;
-	tcon->remap = cifs_remap(cifs_sb);
+	tcon->dfs_path = ref_path;
+	ref_path = NULL;
 	spin_unlock(&cifs_tcp_ses_lock);
 
-	/* Add original context for DFS cache to be used when refreshing referrals */
-	rc = dfs_cache_add_vol(mntdata, ctx, cifs_sb->origin_fullpath);
-	if (rc)
-		goto error;
 	/*
 	 * After reconnecting to a different server, unique ids won't
 	 * match anymore, so we disable serverino. This prevents
@@ -3514,6 +3501,7 @@ int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
 	kfree(cifs_sb->prepath);
 	cifs_sb->prepath = ctx->prepath;
 	ctx->prepath = NULL;
+	uuid_copy(&cifs_sb->dfs_mount_id, &mount_id);
 
 out:
 	free_xid(xid);
@@ -3523,9 +3511,8 @@ out:
 error:
 	kfree(ref_path);
 	kfree(full_path);
-	kfree(mntdata);
 	kfree(cifs_sb->origin_fullpath);
-	put_root_ses(root_ses);
+	dfs_cache_put_refsrv_sessions(&mount_id);
 	mount_put_conns(cifs_sb, xid, server, ses, tcon);
 	return rc;
 }
@@ -3755,7 +3742,7 @@ cifs_umount(struct cifs_sb_info *cifs_sb)
 
 	kfree(cifs_sb->prepath);
 #ifdef CONFIG_CIFS_DFS_UPCALL
-	dfs_cache_del_vol(cifs_sb->origin_fullpath);
+	dfs_cache_put_refsrv_sessions(&cifs_sb->dfs_mount_id);
 	kfree(cifs_sb->origin_fullpath);
 #endif
 	call_rcu(&cifs_sb->rcu, delayed_free);
diff --git a/fs/cifs/dfs_cache.c b/fs/cifs/dfs_cache.c
index b1fa30fefe1f..7c1769714609 100644
--- a/fs/cifs/dfs_cache.c
+++ b/fs/cifs/dfs_cache.c
@@ -11,6 +11,7 @@
 #include <linux/proc_fs.h>
 #include <linux/nls.h>
 #include <linux/workqueue.h>
+#include <linux/uuid.h>
 #include "cifsglob.h"
 #include "smb2pdu.h"
 #include "smb2proto.h"
@@ -18,15 +19,14 @@
 #include "cifs_debug.h"
 #include "cifs_unicode.h"
 #include "smb2glob.h"
-#include "fs_context.h"
 
 #include "dfs_cache.h"
 
 #define CACHE_HTABLE_SIZE 32
 #define CACHE_MAX_ENTRIES 64
+#define CACHE_MIN_TTL 120 /* 2 minutes */
 
-#define IS_INTERLINK_SET(v) ((v) & (DFSREF_REFERRAL_SERVER | \
-				    DFSREF_STORAGE_SERVER))
+#define IS_DFS_INTERLINK(v) (((v) & DFSREF_REFERRAL_SERVER) && !((v) & DFSREF_STORAGE_SERVER))
 
 struct cache_dfs_tgt {
 	char *name;
@@ -48,14 +48,15 @@ struct cache_entry {
 	struct cache_dfs_tgt *tgthint;
 };
 
-struct vol_info {
-	char *fullpath;
-	spinlock_t ctx_lock;
-	struct smb3_fs_context ctx;
-	char *mntdata;
+/* List of referral server sessions per dfs mount */
+struct mount_group {
 	struct list_head list;
-	struct list_head rlist;
-	struct kref refcnt;
+	uuid_t id;
+	struct cifs_ses *sessions[CACHE_MAX_ENTRIES];
+	int num_sessions;
+	spinlock_t lock;
+	struct list_head refresh_list;
+	struct kref refcount;
 };
 
 static struct kmem_cache *cache_slab __read_mostly;
@@ -64,7 +65,7 @@ static struct workqueue_struct *dfscache_wq __read_mostly;
 static int cache_ttl;
 static DEFINE_SPINLOCK(cache_ttl_lock);
 
-static struct nls_table *cache_nlsc;
+static struct nls_table *cache_cp;
 
 /*
  * Number of entries in the cache
@@ -74,34 +75,145 @@ static atomic_t cache_count;
 static struct hlist_head cache_htable[CACHE_HTABLE_SIZE];
 static DECLARE_RWSEM(htable_rw_lock);
 
-static LIST_HEAD(vol_list);
-static DEFINE_SPINLOCK(vol_list_lock);
+static LIST_HEAD(mount_group_list);
+static DEFINE_MUTEX(mount_group_list_lock);
 
 static void refresh_cache_worker(struct work_struct *work);
 
 static DECLARE_DELAYED_WORK(refresh_task, refresh_cache_worker);
 
-static int get_normalized_path(const char *path, const char **npath)
+static void get_ipc_unc(const char *ref_path, char *ipc, size_t ipclen)
 {
-	if (!path || strlen(path) < 3 || (*path != '\\' && *path != '/'))
-		return -EINVAL;
+	const char *host;
+	size_t len;
 
-	if (*path == '\\') {
-		*npath = path;
-	} else {
-		char *s = kstrdup(path, GFP_KERNEL);
-		if (!s)
-			return -ENOMEM;
-		convert_delimiter(s, '\\');
-		*npath = s;
+	extract_unc_hostname(ref_path, &host, &len);
+	scnprintf(ipc, ipclen, "\\\\%.*s\\IPC$", (int)len, host);
+}
+
+static struct cifs_ses *find_ipc_from_server_path(struct cifs_ses **ses, const char *path)
+{
+	char unc[SERVER_NAME_LENGTH + sizeof("//x/IPC$")] = {0};
+
+	get_ipc_unc(path, unc, sizeof(unc));
+	for (; *ses; ses++) {
+		if (!strcasecmp(unc, (*ses)->tcon_ipc->treeName))
+			return *ses;
 	}
-	return 0;
+	return ERR_PTR(-ENOENT);
+}
+
+static void __mount_group_release(struct mount_group *mg)
+{
+	int i;
+
+	for (i = 0; i < mg->num_sessions; i++)
+		cifs_put_smb_ses(mg->sessions[i]);
+	kfree(mg);
+}
+
+static void mount_group_release(struct kref *kref)
+{
+	struct mount_group *mg = container_of(kref, struct mount_group, refcount);
+
+	mutex_lock(&mount_group_list_lock);
+	list_del(&mg->list);
+	mutex_unlock(&mount_group_list_lock);
+	__mount_group_release(mg);
+}
+
+static struct mount_group *find_mount_group_locked(const uuid_t *id)
+{
+	struct mount_group *mg;
+
+	list_for_each_entry(mg, &mount_group_list, list) {
+		if (uuid_equal(&mg->id, id))
+			return mg;
+	}
+	return ERR_PTR(-ENOENT);
+}
+
+static struct mount_group *__get_mount_group_locked(const uuid_t *id)
+{
+	struct mount_group *mg;
+
+	mg = find_mount_group_locked(id);
+	if (!IS_ERR(mg))
+		return mg;
+
+	mg = kmalloc(sizeof(*mg), GFP_KERNEL);
+	if (!mg)
+		return ERR_PTR(-ENOMEM);
+	kref_init(&mg->refcount);
+	uuid_copy(&mg->id, id);
+	mg->num_sessions = 0;
+	spin_lock_init(&mg->lock);
+	list_add(&mg->list, &mount_group_list);
+	return mg;
+}
+
+static struct mount_group *get_mount_group(const uuid_t *id)
+{
+	struct mount_group *mg;
+
+	mutex_lock(&mount_group_list_lock);
+	mg = __get_mount_group_locked(id);
+	if (!IS_ERR(mg))
+		kref_get(&mg->refcount);
+	mutex_unlock(&mount_group_list_lock);
+
+	return mg;
 }
 
-static inline void free_normalized_path(const char *path, const char *npath)
+static void free_mount_group_list(void)
 {
-	if (path != npath)
-		kfree(npath);
+	struct mount_group *mg, *tmp_mg;
+
+	list_for_each_entry_safe(mg, tmp_mg, &mount_group_list, list) {
+		list_del_init(&mg->list);
+		__mount_group_release(mg);
+	}
+}
+
+/**
+ * dfs_cache_canonical_path - get a canonical DFS path
+ *
+ * @path: DFS path
+ * @cp: codepage
+ * @remap: mapping type
+ *
+ * Return canonical path if success, otherwise error.
+ */
+char *dfs_cache_canonical_path(const char *path, const struct nls_table *cp, int remap)
+{
+	char *tmp;
+	int plen = 0;
+	char *npath;
+
+	if (!path || strlen(path) < 3 || (*path != '\\' && *path != '/'))
+		return ERR_PTR(-EINVAL);
+
+	if (unlikely(strcmp(cp->charset, cache_cp->charset))) {
+		tmp = (char *)cifs_strndup_to_utf16(path, strlen(path), &plen, cp, remap);
+		if (!tmp) {
+			cifs_dbg(VFS, "%s: failed to convert path to utf16\n", __func__);
+			return ERR_PTR(-EINVAL);
+		}
+
+		npath = cifs_strndup_from_utf16(tmp, plen, true, cache_cp);
+		kfree(tmp);
+
+		if (!npath) {
+			cifs_dbg(VFS, "%s: failed to convert path from utf16\n", __func__);
+			return ERR_PTR(-EINVAL);
+		}
+	} else {
+		npath = kstrdup(path, GFP_KERNEL);
+		if (!npath)
+			return ERR_PTR(-ENOMEM);
+	}
+	convert_delimiter(npath, '\\');
+	return npath;
 }
 
 static inline bool cache_entry_expired(const struct cache_entry *ce)
@@ -171,7 +283,7 @@ static int dfscache_proc_show(struct seq_file *m, void *v)
 				   "cache entry: path=%s,type=%s,ttl=%d,etime=%ld,hdr_flags=0x%x,ref_flags=0x%x,interlink=%s,path_consumed=%d,expired=%s\n",
 				   ce->path, ce->srvtype == DFS_TYPE_ROOT ? "root" : "link",
 				   ce->ttl, ce->etime.tv_nsec, ce->ref_flags, ce->hdr_flags,
-				   IS_INTERLINK_SET(ce->hdr_flags) ? "yes" : "no",
+				   IS_DFS_INTERLINK(ce->hdr_flags) ? "yes" : "no",
 				   ce->path_consumed, cache_entry_expired(ce) ? "yes" : "no");
 
 			list_for_each_entry(t, &ce->tlist, list) {
@@ -240,7 +352,7 @@ static inline void dump_ce(const struct cache_entry *ce)
 		 ce->srvtype == DFS_TYPE_ROOT ? "root" : "link", ce->ttl,
 		 ce->etime.tv_nsec,
 		 ce->hdr_flags, ce->ref_flags,
-		 IS_INTERLINK_SET(ce->hdr_flags) ? "yes" : "no",
+		 IS_DFS_INTERLINK(ce->hdr_flags) ? "yes" : "no",
 		 ce->path_consumed,
 		 cache_entry_expired(ce) ? "yes" : "no");
 	dump_tgts(ce);
@@ -284,8 +396,7 @@ int dfs_cache_init(void)
 	int rc;
 	int i;
 
-	dfscache_wq = alloc_workqueue("cifs-dfscache",
-				      WQ_FREEZABLE | WQ_MEM_RECLAIM, 1);
+	dfscache_wq = alloc_workqueue("cifs-dfscache", WQ_FREEZABLE | WQ_UNBOUND, 1);
 	if (!dfscache_wq)
 		return -ENOMEM;
 
@@ -301,7 +412,9 @@ int dfs_cache_init(void)
 		INIT_HLIST_HEAD(&cache_htable[i]);
 
 	atomic_set(&cache_count, 0);
-	cache_nlsc = load_nls_default();
+	cache_cp = load_nls("utf8");
+	if (!cache_cp)
+		cache_cp = load_nls_default();
 
 	cifs_dbg(FYI, "%s: initialized DFS referral cache\n", __func__);
 	return 0;
@@ -311,23 +424,24 @@ out_destroy_wq:
 	return rc;
 }
 
-static inline unsigned int cache_entry_hash(const void *data, int size)
+static int cache_entry_hash(const void *data, int size, unsigned int *hash)
 {
-	unsigned int h;
-
-	h = jhash(data, size, 0);
-	return h & (CACHE_HTABLE_SIZE - 1);
-}
-
-/* Check whether second path component of @path is SYSVOL or NETLOGON */
-static inline bool is_sysvol_or_netlogon(const char *path)
-{
-	const char *s;
-	char sep = path[0];
-
-	s = strchr(path + 1, sep) + 1;
-	return !strncasecmp(s, "sysvol", strlen("sysvol")) ||
-		!strncasecmp(s, "netlogon", strlen("netlogon"));
+	int i, clen;
+	const unsigned char *s = data;
+	wchar_t c;
+	unsigned int h = 0;
+
+	for (i = 0; i < size; i += clen) {
+		clen = cache_cp->char2uni(&s[i], size - i, &c);
+		if (unlikely(clen < 0)) {
+			cifs_dbg(VFS, "%s: can't convert char\n", __func__);
+			return clen;
+		}
+		c = cifs_toupper(c);
+		h = jhash(&c, sizeof(c), h);
+	}
+	*hash = h % CACHE_HTABLE_SIZE;
+	return 0;
 }
 
 /* Return target hint of a DFS cache entry */
@@ -378,7 +492,7 @@ static int copy_ref_data(const struct dfs_info3_param *refs, int numrefs,
 {
 	int i;
 
-	ce->ttl = refs[0].ttl;
+	ce->ttl = max_t(int, refs[0].ttl, CACHE_MIN_TTL);
 	ce->etime = get_expire_time(ce->ttl);
 	ce->srvtype = refs[0].server_type;
 	ce->hdr_flags = refs[0].flags;
@@ -409,9 +523,7 @@ static int copy_ref_data(const struct dfs_info3_param *refs, int numrefs,
 }
 
 /* Allocate a new cache entry */
-static struct cache_entry *alloc_cache_entry(const char *path,
-					     const struct dfs_info3_param *refs,
-					     int numrefs)
+static struct cache_entry *alloc_cache_entry(struct dfs_info3_param *refs, int numrefs)
 {
 	struct cache_entry *ce;
 	int rc;
@@ -420,11 +532,9 @@ static struct cache_entry *alloc_cache_entry(const char *path,
 	if (!ce)
 		return ERR_PTR(-ENOMEM);
 
-	ce->path = kstrdup(path, GFP_KERNEL);
-	if (!ce->path) {
-		kmem_cache_free(cache_slab, ce);
-		return ERR_PTR(-ENOMEM);
-	}
+	ce->path = refs[0].path_name;
+	refs[0].path_name = NULL;
+
 	INIT_HLIST_NODE(&ce->hlist);
 	INIT_LIST_HEAD(&ce->tlist);
 
@@ -437,13 +547,14 @@ static struct cache_entry *alloc_cache_entry(const char *path,
 	return ce;
 }
 
-/* Must be called with htable_rw_lock held */
-static void remove_oldest_entry(void)
+static void remove_oldest_entry_locked(void)
 {
 	int i;
 	struct cache_entry *ce;
 	struct cache_entry *to_del = NULL;
 
+	WARN_ON(!rwsem_is_locked(&htable_rw_lock));
+
 	for (i = 0; i < CACHE_HTABLE_SIZE; i++) {
 		struct hlist_head *l = &cache_htable[i];
 
@@ -467,12 +578,24 @@ static void remove_oldest_entry(void)
 }
 
 /* Add a new DFS cache entry */
-static int add_cache_entry(const char *path, unsigned int hash,
-			   struct dfs_info3_param *refs, int numrefs)
+static int add_cache_entry_locked(struct dfs_info3_param *refs, int numrefs)
 {
+	int rc;
 	struct cache_entry *ce;
+	unsigned int hash;
+
+	WARN_ON(!rwsem_is_locked(&htable_rw_lock));
+
+	if (atomic_read(&cache_count) >= CACHE_MAX_ENTRIES) {
+		cifs_dbg(FYI, "%s: reached max cache size (%d)\n", __func__, CACHE_MAX_ENTRIES);
+		remove_oldest_entry_locked();
+	}
 
-	ce = alloc_cache_entry(path, refs, numrefs);
+	rc = cache_entry_hash(refs[0].path_name, strlen(refs[0].path_name), &hash);
+	if (rc)
+		return rc;
+
+	ce = alloc_cache_entry(refs, numrefs);
 	if (IS_ERR(ce))
 		return PTR_ERR(ce);
 
@@ -486,65 +609,77 @@ static int add_cache_entry(const char *path, unsigned int hash,
 	}
 	spin_unlock(&cache_ttl_lock);
 
-	down_write(&htable_rw_lock);
 	hlist_add_head(&ce->hlist, &cache_htable[hash]);
 	dump_ce(ce);
-	up_write(&htable_rw_lock);
+
+	atomic_inc(&cache_count);
 
 	return 0;
 }
 
-static struct cache_entry *__lookup_cache_entry(const char *path)
+/* Check if two DFS paths are equal.  @s1 and @s2 are expected to be in @cache_cp's charset */
+static bool dfs_path_equal(const char *s1, int len1, const char *s2, int len2)
 {
-	struct cache_entry *ce;
-	unsigned int h;
-	bool found = false;
+	int i, l1, l2;
+	wchar_t c1, c2;
 
-	h = cache_entry_hash(path, strlen(path));
+	if (len1 != len2)
+		return false;
 
-	hlist_for_each_entry(ce, &cache_htable[h], hlist) {
-		if (!strcasecmp(path, ce->path)) {
-			found = true;
-			dump_ce(ce);
-			break;
+	for (i = 0; i < len1; i += l1) {
+		l1 = cache_cp->char2uni(&s1[i], len1 - i, &c1);
+		l2 = cache_cp->char2uni(&s2[i], len2 - i, &c2);
+		if (unlikely(l1 < 0 && l2 < 0)) {
+			if (s1[i] != s2[i])
+				return false;
+			l1 = 1;
+			continue;
 		}
+		if (l1 != l2)
+			return false;
+		if (cifs_toupper(c1) != cifs_toupper(c2))
+			return false;
 	}
+	return true;
+}
 
-	if (!found)
-		ce = ERR_PTR(-ENOENT);
-	return ce;
+static struct cache_entry *__lookup_cache_entry(const char *path, unsigned int hash, int len)
+{
+	struct cache_entry *ce;
+
+	hlist_for_each_entry(ce, &cache_htable[hash], hlist) {
+		if (dfs_path_equal(ce->path, strlen(ce->path), path, len)) {
+			dump_ce(ce);
+			return ce;
+		}
+	}
+	return ERR_PTR(-EEXIST);
 }
 
 /*
- * Find a DFS cache entry in hash table and optionally check prefix path against
- * @path.
- * Use whole path components in the match.
- * Must be called with htable_rw_lock held.
+ * Find a DFS cache entry in hash table and optionally check prefix path against normalized @path.
+ *
+ * Use whole path components in the match.  Must be called with htable_rw_lock held.
  *
- * Return ERR_PTR(-ENOENT) if the entry is not found.
+ * Return ERR_PTR(-EEXIST) if the entry is not found.
  */
-static struct cache_entry *lookup_cache_entry(const char *path, unsigned int *hash)
+static struct cache_entry *lookup_cache_entry(const char *path)
 {
-	struct cache_entry *ce = ERR_PTR(-ENOENT);
-	unsigned int h;
+	struct cache_entry *ce;
 	int cnt = 0;
-	char *npath;
-	char *s, *e;
-	char sep;
-
-	npath = kstrdup(path, GFP_KERNEL);
-	if (!npath)
-		return ERR_PTR(-ENOMEM);
+	const char *s = path, *e;
+	char sep = *s;
+	unsigned int hash;
+	int rc;
 
-	s = npath;
-	sep = *npath;
 	while ((s = strchr(s, sep)) && ++cnt < 3)
 		s++;
 
 	if (cnt < 3) {
-		h = cache_entry_hash(path, strlen(path));
-		ce = __lookup_cache_entry(path);
-		goto out;
+		rc = cache_entry_hash(path, strlen(path), &hash);
+		if (rc)
+			return ERR_PTR(rc);
+		return __lookup_cache_entry(path, hash, strlen(path));
 	}
 	/*
 	 * Handle paths that have more than two path components and are a complete prefix of the DFS
@@ -552,64 +687,29 @@ static struct cache_entry *lookup_cache_entry(const char *path, unsigned int *ha
 	 *
 	 * See MS-DFSC 3.2.5.5 "Receiving a Root Referral Request or Link Referral Request".
 	 */
-	h = cache_entry_hash(npath, strlen(npath));
-	e = npath + strlen(npath) - 1;
+	e = path + strlen(path) - 1;
 	while (e > s) {
-		char tmp;
+		int len;
 
 		/* skip separators */
 		while (e > s && *e == sep)
 			e--;
 		if (e == s)
-			goto out;
-
-		tmp = *(e+1);
-		*(e+1) = 0;
-
-		ce = __lookup_cache_entry(npath);
-		if (!IS_ERR(ce)) {
-			h = cache_entry_hash(npath, strlen(npath));
 			break;
-		}
 
-		*(e+1) = tmp;
+		len = e + 1 - path;
+		rc = cache_entry_hash(path, len, &hash);
+		if (rc)
+			return ERR_PTR(rc);
+		ce = __lookup_cache_entry(path, hash, len);
+		if (!IS_ERR(ce))
+			return ce;
+
 		/* backward until separator */
 		while (e > s && *e != sep)
 			e--;
 	}
-out:
-	if (hash)
-		*hash = h;
-	kfree(npath);
-	return ce;
-}
-
-static void __vol_release(struct vol_info *vi)
-{
-	kfree(vi->fullpath);
-	kfree(vi->mntdata);
-	smb3_cleanup_fs_context_contents(&vi->ctx);
-	kfree(vi);
-}
-
-static void vol_release(struct kref *kref)
-{
-	struct vol_info *vi = container_of(kref, struct vol_info, refcnt);
-
-	spin_lock(&vol_list_lock);
-	list_del(&vi->list);
-	spin_unlock(&vol_list_lock);
-	__vol_release(vi);
-}
-
-static inline void free_vol_list(void)
-{
-	struct vol_info *vi, *nvi;
-
-	list_for_each_entry_safe(vi, nvi, &vol_list, list) {
-		list_del_init(&vi->list);
-		__vol_release(vi);
-	}
+	return ERR_PTR(-EEXIST);
 }
 
 /**
@@ -618,8 +718,8 @@ static inline void free_vol_list(void)
 void dfs_cache_destroy(void)
 {
 	cancel_delayed_work_sync(&refresh_task);
-	unload_nls(cache_nlsc);
-	free_vol_list();
+	unload_nls(cache_cp);
+	free_mount_group_list();
 	flush_cache_ents();
 	kmem_cache_destroy(cache_slab);
 	destroy_workqueue(dfscache_wq);
@@ -627,18 +727,14 @@ void dfs_cache_destroy(void)
 	cifs_dbg(FYI, "%s: destroyed DFS referral cache\n", __func__);
 }
 
-/* Must be called with htable_rw_lock held */
-static int __update_cache_entry(const char *path,
-				const struct dfs_info3_param *refs,
-				int numrefs)
+/* Update a cache entry with the new referral in @refs */
+static int update_cache_entry_locked(struct cache_entry *ce, const struct dfs_info3_param *refs,
+				     int numrefs)
 {
 	int rc;
-	struct cache_entry *ce;
 	char *s, *th = NULL;
 
-	ce = lookup_cache_entry(path, NULL);
-	if (IS_ERR(ce))
-		return PTR_ERR(ce);
+	WARN_ON(!rwsem_is_locked(&htable_rw_lock));
 
 	if (ce->tgthint) {
 		s = ce->tgthint->name;
@@ -657,37 +753,30 @@ static int __update_cache_entry(const char *path,
 	return rc;
 }
 
-static int get_dfs_referral(const unsigned int xid, struct cifs_ses *ses,
-			    const struct nls_table *nls_codepage, int remap,
-			    const char *path,  struct dfs_info3_param **refs,
-			    int *numrefs)
+static int get_dfs_referral(const unsigned int xid, struct cifs_ses *ses, const char *path,
+			    struct dfs_info3_param **refs, int *numrefs)
 {
-	cifs_dbg(FYI, "%s: get an DFS referral for %s\n", __func__, path);
+	int rc;
+	int i;
 
-	if (!ses || !ses->server || !ses->server->ops->get_dfs_refer)
-		return -EOPNOTSUPP;
-	if (unlikely(!nls_codepage))
-		return -EINVAL;
+	cifs_dbg(FYI, "%s: get an DFS referral for %s\n", __func__, path);
 
 	*refs = NULL;
 	*numrefs = 0;
 
-	return ses->server->ops->get_dfs_refer(xid, ses, path, refs, numrefs,
-					       nls_codepage, remap);
-}
-
-/* Update an expired cache entry by getting a new DFS referral from server */
-static int update_cache_entry(const char *path,
-			      const struct dfs_info3_param *refs,
-			      int numrefs)
-{
-
-	int rc;
+	if (!ses || !ses->server || !ses->server->ops->get_dfs_refer)
+		return -EOPNOTSUPP;
+	if (unlikely(!cache_cp))
+		return -EINVAL;
 
-	down_write(&htable_rw_lock);
-	rc = __update_cache_entry(path, refs, numrefs);
-	up_write(&htable_rw_lock);
+	rc =  ses->server->ops->get_dfs_refer(xid, ses, path, refs, numrefs, cache_cp,
+					      NO_MAP_UNI_RSVD);
+	if (!rc) {
+		struct dfs_info3_param *ref = *refs;
 
+		for (i = 0; i < *numrefs; i++)
+			convert_delimiter(ref[i].path_name, '\\');
+	}
 	return rc;
 }
 
@@ -697,15 +786,12 @@ static int update_cache_entry(const char *path,
  * If the entry wasn't found, it will create a new one. Or if it was found but
  * expired, then it will update the entry accordingly.
  *
- * For interlinks, __cifs_dfs_mount() and expand_dfs_referral() are supposed to
+ * For interlinks, cifs_mount() and expand_dfs_referral() are supposed to
  * handle them properly.
  */
-static int __dfs_cache_find(const unsigned int xid, struct cifs_ses *ses,
-			    const struct nls_table *nls_codepage, int remap,
-			    const char *path, bool noreq)
+static int cache_refresh_path(const unsigned int xid, struct cifs_ses *ses, const char *path)
 {
 	int rc;
-	unsigned int hash;
 	struct cache_entry *ce;
 	struct dfs_info3_param *refs = NULL;
 	int numrefs = 0;
@@ -713,62 +799,38 @@ static int __dfs_cache_find(const unsigned int xid, struct cifs_ses *ses,
 
 	cifs_dbg(FYI, "%s: search path: %s\n", __func__, path);
 
-	down_read(&htable_rw_lock);
-
-	ce = lookup_cache_entry(path, &hash);
-
-	/*
-	 * If @noreq is set, no requests will be sent to the server. Just return
-	 * the cache entry.
-	 */
-	if (noreq) {
-		up_read(&htable_rw_lock);
-		return PTR_ERR_OR_ZERO(ce);
-	}
+	down_write(&htable_rw_lock);
 
+	ce = lookup_cache_entry(path);
 	if (!IS_ERR(ce)) {
 		if (!cache_entry_expired(ce)) {
 			dump_ce(ce);
-			up_read(&htable_rw_lock);
+			up_write(&htable_rw_lock);
 			return 0;
 		}
 	} else {
 		newent = true;
 	}
 
-	up_read(&htable_rw_lock);
-
 	/*
-	 * No entry was found.
-	 *
-	 * Request a new DFS referral in order to create a new cache entry, or
-	 * updating an existing one.
+	 * Either the entry was not found, or it is expired.
+	 * Request a new DFS referral in order to create or update a cache entry.
 	 */
-	rc = get_dfs_referral(xid, ses, nls_codepage, remap, path,
-			      &refs, &numrefs);
+	rc = get_dfs_referral(xid, ses, path, &refs, &numrefs);
 	if (rc)
-		return rc;
+		goto out_unlock;
 
 	dump_refs(refs, numrefs);
 
 	if (!newent) {
-		rc = update_cache_entry(path, refs, numrefs);
-		goto out_free_refs;
-	}
-
-	if (atomic_read(&cache_count) >= CACHE_MAX_ENTRIES) {
-		cifs_dbg(FYI, "%s: reached max cache size (%d)\n",
-			 __func__, CACHE_MAX_ENTRIES);
-		down_write(&htable_rw_lock);
-		remove_oldest_entry();
-		up_write(&htable_rw_lock);
+		rc = update_cache_entry_locked(ce, refs, numrefs);
+		goto out_unlock;
 	}
 
-	rc = add_cache_entry(path, hash, refs, numrefs);
-	if (!rc)
-		atomic_inc(&cache_count);
+	rc = add_cache_entry_locked(refs, numrefs);
 
-out_free_refs:
+out_unlock:
+	up_write(&htable_rw_lock);
 	free_dfs_info_array(refs, numrefs);
 	return rc;
 }
@@ -868,7 +930,7 @@ err_free_it:
  * needs to be issued:
  * @xid: syscall xid
  * @ses: smb session to issue the request on
- * @nls_codepage: charset conversion
+ * @cp: codepage
  * @remap: path character remapping type
  * @path: path to lookup in DFS referral cache.
  *
@@ -877,26 +939,25 @@ err_free_it:
  *
  * Return zero if the target was found, otherwise non-zero.
  */
-int dfs_cache_find(const unsigned int xid, struct cifs_ses *ses,
-		   const struct nls_table *nls_codepage, int remap,
-		   const char *path, struct dfs_info3_param *ref,
+int dfs_cache_find(const unsigned int xid, struct cifs_ses *ses, const struct nls_table *cp,
+		   int remap, const char *path, struct dfs_info3_param *ref,
 		   struct dfs_cache_tgt_list *tgt_list)
 {
 	int rc;
 	const char *npath;
 	struct cache_entry *ce;
 
-	rc = get_normalized_path(path, &npath);
-	if (rc)
-		return rc;
+	npath = dfs_cache_canonical_path(path, cp, remap);
+	if (IS_ERR(npath))
+		return PTR_ERR(npath);
 
-	rc = __dfs_cache_find(xid, ses, nls_codepage, remap, npath, false);
+	rc = cache_refresh_path(xid, ses, npath);
 	if (rc)
 		goto out_free_path;
 
 	down_read(&htable_rw_lock);
 
-	ce = lookup_cache_entry(npath, NULL);
+	ce = lookup_cache_entry(npath);
 	if (IS_ERR(ce)) {
 		up_read(&htable_rw_lock);
 		rc = PTR_ERR(ce);
@@ -913,7 +974,7 @@ int dfs_cache_find(const unsigned int xid, struct cifs_ses *ses,
 	up_read(&htable_rw_lock);
 
 out_free_path:
-	free_normalized_path(path, npath);
+	kfree(npath);
 	return rc;
 }
 
@@ -925,7 +986,7 @@ out_free_path:
  * expired, nor create a new cache entry if @path hasn't been found. It heavily
  * relies on an existing cache entry.
  *
- * @path: path to lookup in the DFS referral cache.
+ * @path: canonical DFS path to lookup in the DFS referral cache.
  * @ref: when non-NULL, store single DFS referral result in it.
  * @tgt_list: when non-NULL, store complete DFS target list in it.
  *
@@ -937,18 +998,13 @@ int dfs_cache_noreq_find(const char *path, struct dfs_info3_param *ref,
 			 struct dfs_cache_tgt_list *tgt_list)
 {
 	int rc;
-	const char *npath;
 	struct cache_entry *ce;
 
-	rc = get_normalized_path(path, &npath);
-	if (rc)
-		return rc;
-
-	cifs_dbg(FYI, "%s: path: %s\n", __func__, npath);
+	cifs_dbg(FYI, "%s: path: %s\n", __func__, path);
 
 	down_read(&htable_rw_lock);
 
-	ce = lookup_cache_entry(npath, NULL);
+	ce = lookup_cache_entry(path);
 	if (IS_ERR(ce)) {
 		rc = PTR_ERR(ce);
 		goto out_unlock;
@@ -963,8 +1019,6 @@ int dfs_cache_noreq_find(const char *path, struct dfs_info3_param *ref,
 
 out_unlock:
 	up_read(&htable_rw_lock);
-	free_normalized_path(path, npath);
-
 	return rc;
 }
 
@@ -979,16 +1033,15 @@ out_unlock:
  *
  * @xid: syscall id
  * @ses: smb session
- * @nls_codepage: charset conversion
+ * @cp: codepage
  * @remap: type of character remapping for paths
- * @path: path to lookup in DFS referral cache.
+ * @path: path to lookup in DFS referral cache
  * @it: DFS target iterator
  *
  * Return zero if the target hint was updated successfully, otherwise non-zero.
  */
 int dfs_cache_update_tgthint(const unsigned int xid, struct cifs_ses *ses,
-			     const struct nls_table *nls_codepage, int remap,
-			     const char *path,
+			     const struct nls_table *cp, int remap, const char *path,
 			     const struct dfs_cache_tgt_iterator *it)
 {
 	int rc;
@@ -996,19 +1049,19 @@ int dfs_cache_update_tgthint(const unsigned int xid, struct cifs_ses *ses,
 	struct cache_entry *ce;
 	struct cache_dfs_tgt *t;
 
-	rc = get_normalized_path(path, &npath);
-	if (rc)
-		return rc;
+	npath = dfs_cache_canonical_path(path, cp, remap);
+	if (IS_ERR(npath))
+		return PTR_ERR(npath);
 
 	cifs_dbg(FYI, "%s: update target hint - path: %s\n", __func__, npath);
 
-	rc = __dfs_cache_find(xid, ses, nls_codepage, remap, npath, false);
+	rc = cache_refresh_path(xid, ses, npath);
 	if (rc)
 		goto out_free_path;
 
 	down_write(&htable_rw_lock);
 
-	ce = lookup_cache_entry(npath, NULL);
+	ce = lookup_cache_entry(npath);
 	if (IS_ERR(ce)) {
 		rc = PTR_ERR(ce);
 		goto out_unlock;
@@ -1031,8 +1084,7 @@ int dfs_cache_update_tgthint(const unsigned int xid, struct cifs_ses *ses,
 out_unlock:
 	up_write(&htable_rw_lock);
 out_free_path:
-	free_normalized_path(path, npath);
-
+	kfree(npath);
 	return rc;
 }
 
@@ -1044,32 +1096,26 @@ out_free_path:
  * expired, nor create a new cache entry if @path hasn't been found. It heavily
  * relies on an existing cache entry.
  *
- * @path: path to lookup in DFS referral cache.
+ * @path: canonical DFS path to lookup in DFS referral cache.
  * @it: target iterator which contains the target hint to update the cache
  * entry with.
  *
  * Return zero if the target hint was updated successfully, otherwise non-zero.
  */
-int dfs_cache_noreq_update_tgthint(const char *path,
-				   const struct dfs_cache_tgt_iterator *it)
+int dfs_cache_noreq_update_tgthint(const char *path, const struct dfs_cache_tgt_iterator *it)
 {
 	int rc;
-	const char *npath;
 	struct cache_entry *ce;
 	struct cache_dfs_tgt *t;
 
 	if (!it)
 		return -EINVAL;
 
-	rc = get_normalized_path(path, &npath);
-	if (rc)
-		return rc;
-
-	cifs_dbg(FYI, "%s: path: %s\n", __func__, npath);
+	cifs_dbg(FYI, "%s: path: %s\n", __func__, path);
 
 	down_write(&htable_rw_lock);
 
-	ce = lookup_cache_entry(npath, NULL);
+	ce = lookup_cache_entry(path);
 	if (IS_ERR(ce)) {
 		rc = PTR_ERR(ce);
 		goto out_unlock;
@@ -1092,8 +1138,6 @@ int dfs_cache_noreq_update_tgthint(const char *path,
 
 out_unlock:
 	up_write(&htable_rw_lock);
-	free_normalized_path(path, npath);
-
 	return rc;
 }
 
@@ -1101,32 +1145,26 @@ out_unlock:
  * dfs_cache_get_tgt_referral - returns a DFS referral (@ref) from a given
  * target iterator (@it).
  *
- * @path: path to lookup in DFS referral cache.
+ * @path: canonical DFS path to lookup in DFS referral cache.
  * @it: DFS target iterator.
  * @ref: DFS referral pointer to set up the gathered information.
  *
  * Return zero if the DFS referral was set up correctly, otherwise non-zero.
  */
-int dfs_cache_get_tgt_referral(const char *path,
-			       const struct dfs_cache_tgt_iterator *it,
+int dfs_cache_get_tgt_referral(const char *path, const struct dfs_cache_tgt_iterator *it,
 			       struct dfs_info3_param *ref)
 {
 	int rc;
-	const char *npath;
 	struct cache_entry *ce;
 
 	if (!it || !ref)
 		return -EINVAL;
 
-	rc = get_normalized_path(path, &npath);
-	if (rc)
-		return rc;
-
-	cifs_dbg(FYI, "%s: path: %s\n", __func__, npath);
+	cifs_dbg(FYI, "%s: path: %s\n", __func__, path);
 
 	down_read(&htable_rw_lock);
 
-	ce = lookup_cache_entry(npath, NULL);
+	ce = lookup_cache_entry(path);
 	if (IS_ERR(ce)) {
 		rc = PTR_ERR(ce);
 		goto out_unlock;
@@ -1138,132 +1176,55 @@ int dfs_cache_get_tgt_referral(const char *path,
 
 out_unlock:
 	up_read(&htable_rw_lock);
-	free_normalized_path(path, npath);
-
 	return rc;
 }
 
 /**
- * dfs_cache_add_vol - add a cifs context during mount() that will be handled by
- * DFS cache refresh worker.
- *
- * @mntdata: mount data.
- * @ctx: cifs context.
- * @fullpath: origin full path.
+ * dfs_cache_add_refsrv_session - add SMB session of referral server
  *
- * Return zero if context was set up correctly, otherwise non-zero.
+ * @mount_id: mount group uuid to lookup.
+ * @ses: reference counted SMB session of referral server.
  */
-int dfs_cache_add_vol(char *mntdata, struct smb3_fs_context *ctx, const char *fullpath)
+void dfs_cache_add_refsrv_session(const uuid_t *mount_id, struct cifs_ses *ses)
 {
-	int rc;
-	struct vol_info *vi;
-
-	if (!ctx || !fullpath || !mntdata)
-		return -EINVAL;
-
-	cifs_dbg(FYI, "%s: fullpath: %s\n", __func__, fullpath);
-
-	vi = kzalloc(sizeof(*vi), GFP_KERNEL);
-	if (!vi)
-		return -ENOMEM;
+	struct mount_group *mg;
 
-	vi->fullpath = kstrdup(fullpath, GFP_KERNEL);
-	if (!vi->fullpath) {
-		rc = -ENOMEM;
-		goto err_free_vi;
-	}
-
-	rc = smb3_fs_context_dup(&vi->ctx, ctx);
-	if (rc)
-		goto err_free_fullpath;
-
-	vi->mntdata = mntdata;
-	spin_lock_init(&vi->ctx_lock);
-	kref_init(&vi->refcnt);
-
-	spin_lock(&vol_list_lock);
-	list_add_tail(&vi->list, &vol_list);
-	spin_unlock(&vol_list_lock);
-
-	return 0;
-
-err_free_fullpath:
-	kfree(vi->fullpath);
-err_free_vi:
-	kfree(vi);
-	return rc;
-}
+	if (WARN_ON_ONCE(!mount_id || uuid_is_null(mount_id) || !ses))
+		return;
 
-/* Must be called with vol_list_lock held */
-static struct vol_info *find_vol(const char *fullpath)
-{
-	struct vol_info *vi;
+	mg = get_mount_group(mount_id);
+	if (WARN_ON_ONCE(IS_ERR(mg)))
+		return;
 
-	list_for_each_entry(vi, &vol_list, list) {
-		cifs_dbg(FYI, "%s: vi->fullpath: %s\n", __func__, vi->fullpath);
-		if (!strcasecmp(vi->fullpath, fullpath))
-			return vi;
-	}
-	return ERR_PTR(-ENOENT);
+	spin_lock(&mg->lock);
+	if (mg->num_sessions < ARRAY_SIZE(mg->sessions))
+		mg->sessions[mg->num_sessions++] = ses;
+	spin_unlock(&mg->lock);
+	kref_put(&mg->refcount, mount_group_release);
 }
 
 /**
- * dfs_cache_update_vol - update vol info in DFS cache after failover
+ * dfs_cache_put_refsrv_sessions - put all referral server sessions
  *
- * @fullpath: fullpath to look up in volume list.
- * @server: TCP ses pointer.
+ * Put all SMB sessions from the given mount group id.
  *
- * Return zero if volume was updated, otherwise non-zero.
+ * @mount_id: mount group uuid to lookup.
  */
-int dfs_cache_update_vol(const char *fullpath, struct TCP_Server_Info *server)
+void dfs_cache_put_refsrv_sessions(const uuid_t *mount_id)
 {
-	struct vol_info *vi;
-
-	if (!fullpath || !server)
-		return -EINVAL;
-
-	cifs_dbg(FYI, "%s: fullpath: %s\n", __func__, fullpath);
-
-	spin_lock(&vol_list_lock);
-	vi = find_vol(fullpath);
-	if (IS_ERR(vi)) {
-		spin_unlock(&vol_list_lock);
-		return PTR_ERR(vi);
-	}
-	kref_get(&vi->refcnt);
-	spin_unlock(&vol_list_lock);
-
-	cifs_dbg(FYI, "%s: updating volume info\n", __func__);
-	spin_lock(&vi->ctx_lock);
-	memcpy(&vi->ctx.dstaddr, &server->dstaddr,
-	       sizeof(vi->ctx.dstaddr));
-	spin_unlock(&vi->ctx_lock);
+	struct mount_group *mg;
 
-	kref_put(&vi->refcnt, vol_release);
-
-	return 0;
-}
-
-/**
- * dfs_cache_del_vol - remove volume info in DFS cache during umount()
- *
- * @fullpath: fullpath to look up in volume list.
- */
-void dfs_cache_del_vol(const char *fullpath)
-{
-	struct vol_info *vi;
-
-	if (!fullpath || !*fullpath)
+	if (!mount_id || uuid_is_null(mount_id))
 		return;
 
-	cifs_dbg(FYI, "%s: fullpath: %s\n", __func__, fullpath);
-
-	spin_lock(&vol_list_lock);
-	vi = find_vol(fullpath);
-	spin_unlock(&vol_list_lock);
-
-	if (!IS_ERR(vi))
-		kref_put(&vi->refcnt, vol_release);
+	mutex_lock(&mount_group_list_lock);
+	mg = find_mount_group_locked(mount_id);
+	if (IS_ERR(mg)) {
+		mutex_unlock(&mount_group_list_lock);
+		return;
+	}
+	mutex_unlock(&mount_group_list_lock);
+	kref_put(&mg->refcount, mount_group_release);
 }
 
 /**
@@ -1276,8 +1237,8 @@ void dfs_cache_del_vol(const char *fullpath)
  *
  * Return zero if target was parsed correctly, otherwise non-zero.
  */
-int dfs_cache_get_tgt_share(char *path, const struct dfs_cache_tgt_iterator *it,
-			    char **share, char **prefix)
+int dfs_cache_get_tgt_share(char *path, const struct dfs_cache_tgt_iterator *it, char **share,
+			    char **prefix)
 {
 	char *s, sep, *p;
 	size_t len;
@@ -1332,278 +1293,190 @@ int dfs_cache_get_tgt_share(char *path, const struct dfs_cache_tgt_iterator *it,
 	return 0;
 }
 
-/* Get all tcons that are within a DFS namespace and can be refreshed */
-static void get_tcons(struct TCP_Server_Info *server, struct list_head *head)
+/*
+ * Refresh all active dfs mounts regardless of whether they are in cache or not.
+ * (cache can be cleared)
+ */
+static void refresh_mounts(struct cifs_ses **sessions)
 {
+	struct TCP_Server_Info *server;
 	struct cifs_ses *ses;
-	struct cifs_tcon *tcon;
+	struct cifs_tcon *tcon, *ntcon;
+	struct list_head tcons;
+	unsigned int xid;
 
-	INIT_LIST_HEAD(head);
+	INIT_LIST_HEAD(&tcons);
 
 	spin_lock(&cifs_tcp_ses_lock);
-	list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
-		list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
-			if (!tcon->need_reconnect && !tcon->need_reopen_files &&
-			    tcon->dfs_path) {
-				tcon->tc_count++;
-				list_add_tail(&tcon->ulist, head);
+	list_for_each_entry(server, &cifs_tcp_ses_list, tcp_ses_list) {
+		list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
+			list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
+				if (tcon->dfs_path) {
+					tcon->tc_count++;
+					list_add_tail(&tcon->ulist, &tcons);
+				}
 			}
 		}
-		if (ses->tcon_ipc && !ses->tcon_ipc->need_reconnect &&
-		    ses->tcon_ipc->dfs_path) {
-			list_add_tail(&ses->tcon_ipc->ulist, head);
-		}
 	}
 	spin_unlock(&cifs_tcp_ses_lock);
-}
 
-static bool is_dfs_link(const char *path)
-{
-	char *s;
-
-	s = strchr(path + 1, '\\');
-	if (!s)
-		return false;
-	return !!strchr(s + 1, '\\');
-}
-
-static char *get_dfs_root(const char *path)
-{
-	char *s, *npath;
-
-	s = strchr(path + 1, '\\');
-	if (!s)
-		return ERR_PTR(-EINVAL);
-
-	s = strchr(s + 1, '\\');
-	if (!s)
-		return ERR_PTR(-EINVAL);
-
-	npath = kstrndup(path, s - path, GFP_KERNEL);
-	if (!npath)
-		return ERR_PTR(-ENOMEM);
+	list_for_each_entry_safe(tcon, ntcon, &tcons, ulist) {
+		const char *path = tcon->dfs_path + 1;
+		struct cache_entry *ce;
+		struct dfs_info3_param *refs = NULL;
+		int numrefs = 0;
+		bool needs_refresh = false;
+		int rc = 0;
 
-	return npath;
-}
+		list_del_init(&tcon->ulist);
 
-static inline void put_tcp_server(struct TCP_Server_Info *server)
-{
-	cifs_put_tcp_session(server, 0);
-}
+		ses = find_ipc_from_server_path(sessions, path);
+		if (IS_ERR(ses))
+			goto next_tcon;
 
-static struct TCP_Server_Info *get_tcp_server(struct smb3_fs_context *ctx)
-{
-	struct TCP_Server_Info *server;
+		down_read(&htable_rw_lock);
+		ce = lookup_cache_entry(path);
+		needs_refresh = IS_ERR(ce) || cache_entry_expired(ce);
+		up_read(&htable_rw_lock);
 
-	server = cifs_find_tcp_session(ctx);
-	if (IS_ERR_OR_NULL(server))
-		return NULL;
+		if (!needs_refresh)
+			goto next_tcon;
+
+		xid = get_xid();
+		rc = get_dfs_referral(xid, ses, path, &refs, &numrefs);
+		free_xid(xid);
+
+		/* Create or update a cache entry with the new referral */
+		if (!rc) {
+			down_write(&htable_rw_lock);
+			ce = lookup_cache_entry(path);
+			if (IS_ERR(ce))
+				add_cache_entry_locked(refs, numrefs);
+			else if (cache_entry_expired(ce))
+				update_cache_entry_locked(ce, refs, numrefs);
+			up_write(&htable_rw_lock);
+		}
 
-	spin_lock(&GlobalMid_Lock);
-	if (server->tcpStatus != CifsGood) {
-		spin_unlock(&GlobalMid_Lock);
-		put_tcp_server(server);
-		return NULL;
+next_tcon:
+		free_dfs_info_array(refs, numrefs);
+		cifs_put_tcon(tcon);
 	}
-	spin_unlock(&GlobalMid_Lock);
-
-	return server;
 }
 
-/* Find root SMB session out of a DFS link path */
-static struct cifs_ses *find_root_ses(struct vol_info *vi,
-				      struct cifs_tcon *tcon,
-				      const char *path)
+static void refresh_cache(struct cifs_ses **sessions)
 {
-	char *rpath;
-	int rc;
-	struct cache_entry *ce;
-	struct dfs_info3_param ref = {0};
-	char *mdata = NULL, *devname = NULL;
-	struct TCP_Server_Info *server;
+	int i;
 	struct cifs_ses *ses;
-	struct smb3_fs_context ctx = {NULL};
+	unsigned int xid;
+	char *ref_paths[CACHE_MAX_ENTRIES];
+	int count = 0;
+	struct cache_entry *ce;
 
-	rpath = get_dfs_root(path);
-	if (IS_ERR(rpath))
-		return ERR_CAST(rpath);
+	/*
+	 * Refresh all cached entries.  Get all new referrals outside critical section to avoid
+	 * starvation while performing SMB2 IOCTL on broken or slow connections.
 
+	 * The cache entries may cover more paths than the active mounts
+	 * (e.g. domain-based DFS referrals or multi tier DFS setups).
+	 */
 	down_read(&htable_rw_lock);
+	for (i = 0; i < CACHE_HTABLE_SIZE; i++) {
+		struct hlist_head *l = &cache_htable[i];
 
-	ce = lookup_cache_entry(rpath, NULL);
-	if (IS_ERR(ce)) {
-		up_read(&htable_rw_lock);
-		ses = ERR_CAST(ce);
-		goto out;
-	}
-
-	rc = setup_referral(path, ce, &ref, get_tgt_name(ce));
-	if (rc) {
-		up_read(&htable_rw_lock);
-		ses = ERR_PTR(rc);
-		goto out;
+		hlist_for_each_entry(ce, l, hlist) {
+			if (count == ARRAY_SIZE(ref_paths))
+				goto out_unlock;
+			if (hlist_unhashed(&ce->hlist) || !cache_entry_expired(ce) ||
+			    IS_ERR(find_ipc_from_server_path(sessions, ce->path)))
+				continue;
+			ref_paths[count++] = kstrdup(ce->path, GFP_ATOMIC);
+		}
 	}
 
+out_unlock:
 	up_read(&htable_rw_lock);
 
-	mdata = cifs_compose_mount_options(vi->mntdata, rpath, &ref,
-					   &devname);
-	free_dfs_info_param(&ref);
-
-	if (IS_ERR(mdata)) {
-		ses = ERR_CAST(mdata);
-		mdata = NULL;
-		goto out;
-	}
-
-	rc = cifs_setup_volume_info(&ctx, NULL, devname);
-
-	if (rc) {
-		ses = ERR_PTR(rc);
-		goto out;
-	}
-
-	server = get_tcp_server(&ctx);
-	if (!server) {
-		ses = ERR_PTR(-EHOSTDOWN);
-		goto out;
-	}
-
-	ses = cifs_get_smb_ses(server, &ctx);
-
-out:
-	smb3_cleanup_fs_context_contents(&ctx);
-	kfree(mdata);
-	kfree(rpath);
-	kfree(devname);
-
-	return ses;
-}
-
-/* Refresh DFS cache entry from a given tcon */
-static int refresh_tcon(struct vol_info *vi, struct cifs_tcon *tcon)
-{
-	int rc = 0;
-	unsigned int xid;
-	const char *path, *npath;
-	struct cache_entry *ce;
-	struct cifs_ses *root_ses = NULL, *ses;
-	struct dfs_info3_param *refs = NULL;
-	int numrefs = 0;
-
-	xid = get_xid();
-
-	path = tcon->dfs_path + 1;
+	for (i = 0; i < count; i++) {
+		char *path = ref_paths[i];
+		struct dfs_info3_param *refs = NULL;
+		int numrefs = 0;
+		int rc = 0;
 
-	rc = get_normalized_path(path, &npath);
-	if (rc)
-		goto out_free_xid;
-
-	down_read(&htable_rw_lock);
-
-	ce = lookup_cache_entry(npath, NULL);
-	if (IS_ERR(ce)) {
-		rc = PTR_ERR(ce);
-		up_read(&htable_rw_lock);
-		goto out_free_path;
-	}
+		if (!path)
+			continue;
 
-	if (!cache_entry_expired(ce)) {
-		up_read(&htable_rw_lock);
-		goto out_free_path;
-	}
+		ses = find_ipc_from_server_path(sessions, path);
+		if (IS_ERR(ses))
+			goto next_referral;
 
-	up_read(&htable_rw_lock);
+		xid = get_xid();
+		rc = get_dfs_referral(xid, ses, path, &refs, &numrefs);
+		free_xid(xid);
 
-	/* If it's a DFS Link, then use root SMB session for refreshing it */
-	if (is_dfs_link(npath)) {
-		ses = root_ses = find_root_ses(vi, tcon, npath);
-		if (IS_ERR(ses)) {
-			rc = PTR_ERR(ses);
-			root_ses = NULL;
-			goto out_free_path;
+		if (!rc) {
+			down_write(&htable_rw_lock);
+			ce = lookup_cache_entry(path);
+			/*
+			 * We need to re-check it because other tasks might have it deleted or
+			 * updated.
+			 */
+			if (!IS_ERR(ce) && cache_entry_expired(ce))
+				update_cache_entry_locked(ce, refs, numrefs);
+			up_write(&htable_rw_lock);
 		}
-	} else {
-		ses = tcon->ses;
-	}
 
-	rc = get_dfs_referral(xid, ses, cache_nlsc, tcon->remap, npath, &refs,
-			      &numrefs);
-	if (!rc) {
-		dump_refs(refs, numrefs);
-		rc = update_cache_entry(npath, refs, numrefs);
+next_referral:
+		kfree(path);
 		free_dfs_info_array(refs, numrefs);
 	}
-
-	if (root_ses)
-		cifs_put_smb_ses(root_ses);
-
-out_free_path:
-	free_normalized_path(path, npath);
-
-out_free_xid:
-	free_xid(xid);
-	return rc;
 }
 
 /*
- * Worker that will refresh DFS cache based on lowest TTL value from a DFS
+ * Worker that will refresh DFS cache and active mounts based on lowest TTL value from a DFS
  * referral.
  */
 static void refresh_cache_worker(struct work_struct *work)
 {
-	struct vol_info *vi, *nvi;
-	struct TCP_Server_Info *server;
-	LIST_HEAD(vols);
-	LIST_HEAD(tcons);
-	struct cifs_tcon *tcon, *ntcon;
-	int rc;
-
-	/*
-	 * Find SMB volumes that are eligible (server->tcpStatus == CifsGood)
-	 * for refreshing.
-	 */
-	spin_lock(&vol_list_lock);
-	list_for_each_entry(vi, &vol_list, list) {
-		server = get_tcp_server(&vi->ctx);
-		if (!server)
-			continue;
-
-		kref_get(&vi->refcnt);
-		list_add_tail(&vi->rlist, &vols);
-		put_tcp_server(server);
+	struct list_head mglist;
+	struct mount_group *mg, *tmp_mg;
+	struct cifs_ses *sessions[CACHE_MAX_ENTRIES + 1] = {NULL};
+	int max_sessions = ARRAY_SIZE(sessions) - 1;
+	int i = 0, count;
+
+	INIT_LIST_HEAD(&mglist);
+
+	/* Get refereces of mount groups */
+	mutex_lock(&mount_group_list_lock);
+	list_for_each_entry(mg, &mount_group_list, list) {
+		kref_get(&mg->refcount);
+		list_add(&mg->refresh_list, &mglist);
 	}
-	spin_unlock(&vol_list_lock);
-
-	/* Walk through all TCONs and refresh any expired cache entry */
-	list_for_each_entry_safe(vi, nvi, &vols, rlist) {
-		spin_lock(&vi->ctx_lock);
-		server = get_tcp_server(&vi->ctx);
-		spin_unlock(&vi->ctx_lock);
+	mutex_unlock(&mount_group_list_lock);
 
-		if (!server)
-			goto next_vol;
-
-		get_tcons(server, &tcons);
-		rc = 0;
-
-		list_for_each_entry_safe(tcon, ntcon, &tcons, ulist) {
-			/*
-			 * Skip tcp server if any of its tcons failed to refresh
-			 * (possibily due to reconnects).
-			 */
-			if (!rc)
-				rc = refresh_tcon(vi, tcon);
+	/* Fill in local array with an NULL-terminated list of all referral server sessions */
+	list_for_each_entry(mg, &mglist, refresh_list) {
+		if (i >= max_sessions)
+			break;
 
-			list_del_init(&tcon->ulist);
-			cifs_put_tcon(tcon);
-		}
+		spin_lock(&mg->lock);
+		if (i + mg->num_sessions > max_sessions)
+			count = max_sessions - i;
+		else
+			count = mg->num_sessions;
+		memcpy(&sessions[i], mg->sessions, count * sizeof(mg->sessions[0]));
+		spin_unlock(&mg->lock);
+		i += count;
+	}
 
-		put_tcp_server(server);
+	if (sessions[0]) {
+		/* Refresh all active mounts and cached entries */
+		refresh_mounts(sessions);
+		refresh_cache(sessions);
+	}
 
-next_vol:
-		list_del_init(&vi->rlist);
-		kref_put(&vi->refcnt, vol_release);
+	list_for_each_entry_safe(mg, tmp_mg, &mglist, refresh_list) {
+		list_del_init(&mg->refresh_list);
+		kref_put(&mg->refcount, mount_group_release);
 	}
 
 	spin_lock(&cache_ttl_lock);
diff --git a/fs/cifs/dfs_cache.h b/fs/cifs/dfs_cache.h
index 1afc4f590c47..b29d3ae64829 100644
--- a/fs/cifs/dfs_cache.h
+++ b/fs/cifs/dfs_cache.h
@@ -10,6 +10,7 @@
 
 #include <linux/nls.h>
 #include <linux/list.h>
+#include <linux/uuid.h>
 #include "cifsglob.h"
 
 struct dfs_cache_tgt_list {
@@ -23,34 +24,26 @@ struct dfs_cache_tgt_iterator {
 	struct list_head it_list;
 };
 
-extern int dfs_cache_init(void);
-extern void dfs_cache_destroy(void);
+int dfs_cache_init(void);
+void dfs_cache_destroy(void);
 extern const struct proc_ops dfscache_proc_ops;
 
-extern int dfs_cache_find(const unsigned int xid, struct cifs_ses *ses,
-			  const struct nls_table *nls_codepage, int remap,
-			  const char *path, struct dfs_info3_param *ref,
-			  struct dfs_cache_tgt_list *tgt_list);
-extern int dfs_cache_noreq_find(const char *path, struct dfs_info3_param *ref,
-				struct dfs_cache_tgt_list *tgt_list);
-extern int dfs_cache_update_tgthint(const unsigned int xid,
-				    struct cifs_ses *ses,
-				    const struct nls_table *nls_codepage,
-				    int remap, const char *path,
-				    const struct dfs_cache_tgt_iterator *it);
-extern int
-dfs_cache_noreq_update_tgthint(const char *path,
-			       const struct dfs_cache_tgt_iterator *it);
-extern int dfs_cache_get_tgt_referral(const char *path,
-				      const struct dfs_cache_tgt_iterator *it,
-				      struct dfs_info3_param *ref);
-extern int dfs_cache_add_vol(char *mntdata, struct smb3_fs_context *ctx,
-			const char *fullpath);
-extern int dfs_cache_update_vol(const char *fullpath,
-				struct TCP_Server_Info *server);
-extern void dfs_cache_del_vol(const char *fullpath);
-extern int dfs_cache_get_tgt_share(char *path, const struct dfs_cache_tgt_iterator *it,
-				   char **share, char **prefix);
+int dfs_cache_find(const unsigned int xid, struct cifs_ses *ses, const struct nls_table *cp,
+		   int remap, const char *path, struct dfs_info3_param *ref,
+		   struct dfs_cache_tgt_list *tgt_list);
+int dfs_cache_noreq_find(const char *path, struct dfs_info3_param *ref,
+			 struct dfs_cache_tgt_list *tgt_list);
+int dfs_cache_update_tgthint(const unsigned int xid, struct cifs_ses *ses,
+			     const struct nls_table *cp, int remap, const char *path,
+			     const struct dfs_cache_tgt_iterator *it);
+int dfs_cache_noreq_update_tgthint(const char *path, const struct dfs_cache_tgt_iterator *it);
+int dfs_cache_get_tgt_referral(const char *path, const struct dfs_cache_tgt_iterator *it,
+			       struct dfs_info3_param *ref);
+int dfs_cache_get_tgt_share(char *path, const struct dfs_cache_tgt_iterator *it, char **share,
+			    char **prefix);
+void dfs_cache_put_refsrv_sessions(const uuid_t *mount_id);
+void dfs_cache_add_refsrv_session(const uuid_t *mount_id, struct cifs_ses *ses);
+char *dfs_cache_canonical_path(const char *path, const struct nls_table *cp, int remap);
 
 static inline struct dfs_cache_tgt_iterator *
 dfs_cache_get_next_tgt(struct dfs_cache_tgt_list *tl,
diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c
index 6bcd3e8f7cda..79402ca0ddfa 100644
--- a/fs/cifs/dir.c
+++ b/fs/cifs/dir.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/dir.c
  *
@@ -6,19 +7,6 @@
  *   Copyright (C) International Business Machines  Corp., 2002,2009
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 #include <linux/fs.h>
 #include <linux/stat.h>
@@ -396,10 +384,11 @@ cifs_create_set_dentry:
 		goto out_err;
 	}
 
-	if (S_ISDIR(newinode->i_mode)) {
-		rc = -EISDIR;
-		goto out_err;
-	}
+	if (newinode)
+		if (S_ISDIR(newinode->i_mode)) {
+			rc = -EISDIR;
+			goto out_err;
+		}
 
 	d_drop(direntry);
 	d_add(direntry, newinode);
@@ -630,6 +619,7 @@ cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
 	struct inode *newInode = NULL;
 	const char *full_path;
 	void *page;
+	int retry_count = 0;
 
 	xid = get_xid();
 
@@ -673,6 +663,7 @@ cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
 	cifs_dbg(FYI, "Full path: %s inode = 0x%p\n",
 		 full_path, d_inode(direntry));
 
+again:
 	if (pTcon->posix_extensions)
 		rc = smb311_posix_get_inode_info(&newInode, full_path, parent_dir_inode->i_sb, xid);
 	else if (pTcon->unix_ext) {
@@ -687,6 +678,8 @@ cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
 		/* since paths are not looked up by component - the parent
 		   directories are presumed to be good here */
 		renew_parental_timestamps(direntry);
+	} else if (rc == -EAGAIN && retry_count++ < 10) {
+		goto again;
 	} else if (rc == -ENOENT) {
 		cifs_set_time(direntry, jiffies);
 		newInode = NULL;
diff --git a/fs/cifs/dns_resolve.c b/fs/cifs/dns_resolve.c
index 534cbba72789..d15b82d569ef 100644
--- a/fs/cifs/dns_resolve.c
+++ b/fs/cifs/dns_resolve.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *  fs/cifs/dns_resolve.c
  *
@@ -10,19 +11,6 @@
  *   Contains the CIFS DFS upcall routines used for hostname to
  *   IP address translation.
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
 #include <linux/slab.h>
diff --git a/fs/cifs/dns_resolve.h b/fs/cifs/dns_resolve.h
index d3f5d27f4d06..5be060b82b13 100644
--- a/fs/cifs/dns_resolve.h
+++ b/fs/cifs/dns_resolve.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: LGPL-2.1 */
 /*
  *   fs/cifs/dns_resolve.h -- DNS Resolver upcall management for CIFS DFS
  *                            Handles host name to IP address resolution
@@ -5,19 +6,6 @@
  *   Copyright (c) International Business Machines  Corp., 2008
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
 #ifndef _DNS_RESOLVE_H
diff --git a/fs/cifs/export.c b/fs/cifs/export.c
index eb0bb8ca8e63..747a540db954 100644
--- a/fs/cifs/export.c
+++ b/fs/cifs/export.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/export.c
  *
@@ -8,19 +9,6 @@
  *
  *   Operations related to support for exporting files via NFSD
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
  /*
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 379a427f3c2f..cd108607a070 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/file.c
  *
@@ -7,19 +8,6 @@
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *              Jeremy Allison (jra@samba.org)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 #include <linux/fs.h>
 #include <linux/backing-dev.h>
diff --git a/fs/cifs/fscache.c b/fs/cifs/fscache.c
index 20d24af33ee2..dd625033cd6b 100644
--- a/fs/cifs/fscache.c
+++ b/fs/cifs/fscache.c
@@ -1,22 +1,10 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/fscache.c - CIFS filesystem cache interface
  *
  *   Copyright (c) 2010 Novell, Inc.
  *   Author(s): Suresh Jayaraman <sjayaraman@suse.de>
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 #include "fscache.h"
 #include "cifsglob.h"
diff --git a/fs/cifs/fscache.h b/fs/cifs/fscache.h
index e811f2dd7619..3d55cb2ef055 100644
--- a/fs/cifs/fscache.h
+++ b/fs/cifs/fscache.h
@@ -1,22 +1,10 @@
+/* SPDX-License-Identifier: LGPL-2.1 */
 /*
  *   fs/cifs/fscache.h - CIFS filesystem cache interface definitions
  *
  *   Copyright (c) 2010 Novell, Inc.
  *   Authors(s): Suresh Jayaraman (sjayaraman@suse.de>
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 #ifndef _CIFS_FSCACHE_H
 #define _CIFS_FSCACHE_H
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 1dfa57982522..b96b253e7635 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -1,22 +1,10 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/inode.c
  *
  *   Copyright (C) International Business Machines  Corp., 2002,2010
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 #include <linux/fs.h>
 #include <linux/stat.h>
@@ -367,9 +355,12 @@ cifs_get_file_info_unix(struct file *filp)
 	} else if (rc == -EREMOTE) {
 		cifs_create_dfs_fattr(&fattr, inode->i_sb);
 		rc = 0;
-	}
+	} else
+		goto cifs_gfiunix_out;
 
 	rc = cifs_fattr_to_inode(inode, &fattr);
+
+cifs_gfiunix_out:
 	free_xid(xid);
 	return rc;
 }
diff --git a/fs/cifs/ioctl.c b/fs/cifs/ioctl.c
index d67d281ab863..42c6a0bac6c8 100644
--- a/fs/cifs/ioctl.c
+++ b/fs/cifs/ioctl.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/ioctl.c
  *
@@ -6,19 +7,6 @@
  *   Copyright (C) International Business Machines  Corp., 2005,2013
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
 #include <linux/fs.h>
diff --git a/fs/cifs/link.c b/fs/cifs/link.c
index 970fcf2adb08..f0a6d63bc08c 100644
--- a/fs/cifs/link.c
+++ b/fs/cifs/link.c
@@ -1,22 +1,10 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/link.c
  *
  *   Copyright (C) International Business Machines  Corp., 2002,2008
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 #include <linux/fs.h>
 #include <linux/stat.h>
diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c
index 7207a63819cb..184138b4eb8c 100644
--- a/fs/cifs/misc.c
+++ b/fs/cifs/misc.c
@@ -1,22 +1,10 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/misc.c
  *
  *   Copyright (C) International Business Machines  Corp., 2002,2008
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
 #include <linux/slab.h>
diff --git a/fs/cifs/netlink.c b/fs/cifs/netlink.c
index 5aaabe4cc0a7..291cb606f149 100644
--- a/fs/cifs/netlink.c
+++ b/fs/cifs/netlink.c
@@ -30,7 +30,7 @@ static const struct nla_policy cifs_genl_policy[CIFS_GENL_ATTR_MAX + 1] = {
 	[CIFS_GENL_ATTR_SWN_RESOURCE_NAME]	= { .type = NLA_STRING},
 };
 
-static struct genl_ops cifs_genl_ops[] = {
+static const struct genl_ops cifs_genl_ops[] = {
 	{
 		.cmd = CIFS_GENL_CMD_SWN_NOTIFY,
 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
diff --git a/fs/cifs/ntlmssp.h b/fs/cifs/ntlmssp.h
index 3079b38f0afb..378133ce8869 100644
--- a/fs/cifs/ntlmssp.h
+++ b/fs/cifs/ntlmssp.h
@@ -1,22 +1,10 @@
+/* SPDX-License-Identifier: LGPL-2.1 */
 /*
  *   fs/cifs/ntlmssp.h
  *
  *   Copyright (c) International Business Machines  Corp., 2002,2007
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
 #define NTLMSSP_SIGNATURE "NTLMSSP"
diff --git a/fs/cifs/readdir.c b/fs/cifs/readdir.c
index 63bfc533c9fb..bfee176b901d 100644
--- a/fs/cifs/readdir.c
+++ b/fs/cifs/readdir.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/readdir.c
  *
@@ -7,19 +8,6 @@
  *   Copyright (C) Red Hat, Inc., 2011
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 #include <linux/fs.h>
 #include <linux/pagemap.h>
@@ -321,7 +309,7 @@ static void cifs_fulldir_info_to_fattr(struct cifs_fattr *fattr,
 {
 	__dir_info_to_fattr(fattr, info);
 
-	/* See MS-FSCC 2.4.18 FileIdFullDirectoryInformation */
+	/* See MS-FSCC 2.4.19 FileIdFullDirectoryInformation */
 	if (fattr->cf_cifsattrs & ATTR_REPARSE)
 		fattr->cf_cifstag = le32_to_cpu(info->EaSize);
 	cifs_fill_common_info(fattr, cifs_sb);
diff --git a/fs/cifs/rfc1002pdu.h b/fs/cifs/rfc1002pdu.h
index 8b69fcceb597..137f7c95afd6 100644
--- a/fs/cifs/rfc1002pdu.h
+++ b/fs/cifs/rfc1002pdu.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: LGPL-2.1 */
 /*
  *   fs/cifs/rfc1002pdu.h
  *
@@ -6,19 +7,6 @@
  *   Copyright (c) International Business Machines  Corp., 2004
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
 /* NB: unlike smb/cifs packets, the RFC1002 structures are big endian */
diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
index a92a1fb7cb52..c5785fd3f52e 100644
--- a/fs/cifs/sess.c
+++ b/fs/cifs/sess.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/sess.c
  *
@@ -6,19 +7,6 @@
  *   Copyright (c) International Business Machines  Corp., 2006, 2009
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
 #include "cifspdu.h"
@@ -195,7 +183,7 @@ cifs_ses_add_channel(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
 			 ses, iface->speed, iface->rdma_capable ? "yes" : "no",
 			 &ipv4->sin_addr);
 	else
-		cifs_dbg(FYI, "adding channel to ses %p (speed:%zu bps rdma:%s ip:%pI4)\n",
+		cifs_dbg(FYI, "adding channel to ses %p (speed:%zu bps rdma:%s ip:%pI6)\n",
 			 ses, iface->speed, iface->rdma_capable ? "yes" : "no",
 			 &ipv6->sin6_addr);
 
diff --git a/fs/cifs/smb2file.c b/fs/cifs/smb2file.c
index 2fa3ba354cc9..c9d8a50062b8 100644
--- a/fs/cifs/smb2file.c
+++ b/fs/cifs/smb2file.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/smb2file.c
  *
@@ -5,19 +6,6 @@
  *   Author(s): Steve French (sfrench@us.ibm.com),
  *              Pavel Shilovsky ((pshilovsky@samba.org) 2012
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 #include <linux/fs.h>
 #include <linux/stat.h>
diff --git a/fs/cifs/smb2glob.h b/fs/cifs/smb2glob.h
index d9a990c99121..d0e9f3782bd9 100644
--- a/fs/cifs/smb2glob.h
+++ b/fs/cifs/smb2glob.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: LGPL-2.1 */
 /*
  *   fs/cifs/smb2glob.h
  *
@@ -9,16 +10,6 @@
  *              Jeremy Allison (jra@samba.org)
  *              Pavel Shilovsky (pshilovsky@samba.org) 2012
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
  */
 #ifndef _SMB2_GLOB_H
 #define _SMB2_GLOB_H
diff --git a/fs/cifs/smb2inode.c b/fs/cifs/smb2inode.c
index 9a61209a283e..957b2594f02e 100644
--- a/fs/cifs/smb2inode.c
+++ b/fs/cifs/smb2inode.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/smb2inode.c
  *
@@ -6,19 +7,6 @@
  *   Author(s): Pavel Shilovsky (pshilovsky@samba.org),
  *              Steve French (sfrench@us.ibm.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 #include <linux/fs.h>
 #include <linux/stat.h>
diff --git a/fs/cifs/smb2maperror.c b/fs/cifs/smb2maperror.c
index c775682ee973..cea39bcecbab 100644
--- a/fs/cifs/smb2maperror.c
+++ b/fs/cifs/smb2maperror.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/smb2/smb2maperror.c
  *
@@ -6,19 +7,6 @@
  *   Copyright (C) International Business Machines  Corp., 2009
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 #include <linux/errno.h>
 #include "cifsglob.h"
diff --git a/fs/cifs/smb2misc.c b/fs/cifs/smb2misc.c
index 06d555d4da9a..668f77108831 100644
--- a/fs/cifs/smb2misc.c
+++ b/fs/cifs/smb2misc.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/smb2misc.c
  *
@@ -6,19 +7,6 @@
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *              Pavel Shilovsky (pshilovsky@samba.org) 2012
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 #include <linux/ctype.h>
 #include "smb2pdu.h"
@@ -164,19 +152,16 @@ smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *srvr)
 		struct smb2_transform_hdr *thdr =
 			(struct smb2_transform_hdr *)buf;
 		struct cifs_ses *ses = NULL;
-		struct list_head *tmp;
 
 		/* decrypt frame now that it is completely read in */
 		spin_lock(&cifs_tcp_ses_lock);
-		list_for_each(tmp, &srvr->smb_ses_list) {
-			ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
+		list_for_each_entry(ses, &srvr->smb_ses_list, smb_ses_list) {
 			if (ses->Suid == thdr->SessionId)
 				break;
-
-			ses = NULL;
 		}
 		spin_unlock(&cifs_tcp_ses_lock);
-		if (ses == NULL) {
+		if (list_entry_is_head(ses, &srvr->smb_ses_list,
+				       smb_ses_list)) {
 			cifs_dbg(VFS, "no decryption - session id not found\n");
 			return 1;
 		}
@@ -548,7 +533,6 @@ static bool
 smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp)
 {
 	__u8 lease_state;
-	struct list_head *tmp;
 	struct cifsFileInfo *cfile;
 	struct cifsInodeInfo *cinode;
 	int ack_req = le32_to_cpu(rsp->Flags &
@@ -556,8 +540,7 @@ smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp)
 
 	lease_state = le32_to_cpu(rsp->NewLeaseState);
 
-	list_for_each(tmp, &tcon->openFileList) {
-		cfile = list_entry(tmp, struct cifsFileInfo, tlist);
+	list_for_each_entry(cfile, &tcon->openFileList, tlist) {
 		cinode = CIFS_I(d_inode(cfile->dentry));
 
 		if (memcmp(cinode->lease_key, rsp->LeaseKey,
@@ -618,7 +601,6 @@ static bool
 smb2_is_valid_lease_break(char *buffer)
 {
 	struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
-	struct list_head *tmp, *tmp1, *tmp2;
 	struct TCP_Server_Info *server;
 	struct cifs_ses *ses;
 	struct cifs_tcon *tcon;
@@ -628,15 +610,9 @@ smb2_is_valid_lease_break(char *buffer)
 
 	/* look up tcon based on tid & uid */
 	spin_lock(&cifs_tcp_ses_lock);
-	list_for_each(tmp, &cifs_tcp_ses_list) {
-		server = list_entry(tmp, struct TCP_Server_Info, tcp_ses_list);
-
-		list_for_each(tmp1, &server->smb_ses_list) {
-			ses = list_entry(tmp1, struct cifs_ses, smb_ses_list);
-
-			list_for_each(tmp2, &ses->tcon_list) {
-				tcon = list_entry(tmp2, struct cifs_tcon,
-						  tcon_list);
+	list_for_each_entry(server, &cifs_tcp_ses_list, tcp_ses_list) {
+		list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
+			list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
 				spin_lock(&tcon->open_file_lock);
 				cifs_stats_inc(
 				    &tcon->stats.cifs_stats.num_oplock_brks);
@@ -687,7 +663,6 @@ bool
 smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
 {
 	struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
-	struct list_head *tmp, *tmp1, *tmp2;
 	struct cifs_ses *ses;
 	struct cifs_tcon *tcon;
 	struct cifsInodeInfo *cinode;
@@ -710,16 +685,11 @@ smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
 
 	/* look up tcon based on tid & uid */
 	spin_lock(&cifs_tcp_ses_lock);
-	list_for_each(tmp, &server->smb_ses_list) {
-		ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
-
-		list_for_each(tmp1, &ses->tcon_list) {
-			tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
+	list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
+		list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
 
 			spin_lock(&tcon->open_file_lock);
-			list_for_each(tmp2, &tcon->openFileList) {
-				cfile = list_entry(tmp2, struct cifsFileInfo,
-						     tlist);
+			list_for_each_entry(cfile, &tcon->openFileList, tlist) {
 				if (rsp->PersistentFid !=
 				    cfile->fid.persistent_fid ||
 				    rsp->VolatileFid !=
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index 21ef51d338e0..e4c8f603dd58 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -388,7 +388,9 @@ smb2_negotiate(const unsigned int xid, struct cifs_ses *ses)
 {
 	int rc;
 
+	spin_lock(&GlobalMid_Lock);
 	cifs_ses_server(ses)->CurrentMid = 0;
+	spin_unlock(&GlobalMid_Lock);
 	rc = SMB2_negotiate(xid, ses);
 	/* BB we probably don't need to retry with modern servers */
 	if (rc == -EAGAIN)
@@ -2325,6 +2327,7 @@ smb2_query_dir_first(const unsigned int xid, struct cifs_tcon *tcon,
 	struct smb2_query_directory_rsp *qd_rsp = NULL;
 	struct smb2_create_rsp *op_rsp = NULL;
 	struct TCP_Server_Info *server = cifs_pick_channel(tcon->ses);
+	int retry_count = 0;
 
 	utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
 	if (!utf16_path)
@@ -2372,10 +2375,14 @@ smb2_query_dir_first(const unsigned int xid, struct cifs_tcon *tcon,
 
 	smb2_set_related(&rqst[1]);
 
+again:
 	rc = compound_send_recv(xid, tcon->ses, server,
 				flags, 2, rqst,
 				resp_buftype, rsp_iov);
 
+	if (rc == -EAGAIN && retry_count++ < 10)
+		goto again;
+
 	/* If the open failed there is nothing to do */
 	op_rsp = (struct smb2_create_rsp *)rsp_iov[0].iov_base;
 	if (op_rsp == NULL || op_rsp->sync_hdr.Status != STATUS_SUCCESS) {
@@ -3601,6 +3608,119 @@ static long smb3_punch_hole(struct file *file, struct cifs_tcon *tcon,
 	return rc;
 }
 
+static int smb3_simple_fallocate_write_range(unsigned int xid,
+					     struct cifs_tcon *tcon,
+					     struct cifsFileInfo *cfile,
+					     loff_t off, loff_t len,
+					     char *buf)
+{
+	struct cifs_io_parms io_parms = {0};
+	int nbytes;
+	struct kvec iov[2];
+
+	io_parms.netfid = cfile->fid.netfid;
+	io_parms.pid = current->tgid;
+	io_parms.tcon = tcon;
+	io_parms.persistent_fid = cfile->fid.persistent_fid;
+	io_parms.volatile_fid = cfile->fid.volatile_fid;
+	io_parms.offset = off;
+	io_parms.length = len;
+
+	/* iov[0] is reserved for smb header */
+	iov[1].iov_base = buf;
+	iov[1].iov_len = io_parms.length;
+	return SMB2_write(xid, &io_parms, &nbytes, iov, 1);
+}
+
+static int smb3_simple_fallocate_range(unsigned int xid,
+				       struct cifs_tcon *tcon,
+				       struct cifsFileInfo *cfile,
+				       loff_t off, loff_t len)
+{
+	struct file_allocated_range_buffer in_data, *out_data = NULL, *tmp_data;
+	u32 out_data_len;
+	char *buf = NULL;
+	loff_t l;
+	int rc;
+
+	in_data.file_offset = cpu_to_le64(off);
+	in_data.length = cpu_to_le64(len);
+	rc = SMB2_ioctl(xid, tcon, cfile->fid.persistent_fid,
+			cfile->fid.volatile_fid,
+			FSCTL_QUERY_ALLOCATED_RANGES, true,
+			(char *)&in_data, sizeof(in_data),
+			1024 * sizeof(struct file_allocated_range_buffer),
+			(char **)&out_data, &out_data_len);
+	if (rc)
+		goto out;
+	/*
+	 * It is already all allocated
+	 */
+	if (out_data_len == 0)
+		goto out;
+
+	buf = kzalloc(1024 * 1024, GFP_KERNEL);
+	if (buf == NULL) {
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	tmp_data = out_data;
+	while (len) {
+		/*
+		 * The rest of the region is unmapped so write it all.
+		 */
+		if (out_data_len == 0) {
+			rc = smb3_simple_fallocate_write_range(xid, tcon,
+					       cfile, off, len, buf);
+			goto out;
+		}
+
+		if (out_data_len < sizeof(struct file_allocated_range_buffer)) {
+			rc = -EINVAL;
+			goto out;
+		}
+
+		if (off < le64_to_cpu(tmp_data->file_offset)) {
+			/*
+			 * We are at a hole. Write until the end of the region
+			 * or until the next allocated data,
+			 * whichever comes next.
+			 */
+			l = le64_to_cpu(tmp_data->file_offset) - off;
+			if (len < l)
+				l = len;
+			rc = smb3_simple_fallocate_write_range(xid, tcon,
+					       cfile, off, l, buf);
+			if (rc)
+				goto out;
+			off = off + l;
+			len = len - l;
+			if (len == 0)
+				goto out;
+		}
+		/*
+		 * We are at a section of allocated data, just skip forward
+		 * until the end of the data or the end of the region
+		 * we are supposed to fallocate, whichever comes first.
+		 */
+		l = le64_to_cpu(tmp_data->length);
+		if (len < l)
+			l = len;
+		off += l;
+		len -= l;
+
+		tmp_data = &tmp_data[1];
+		out_data_len -= sizeof(struct file_allocated_range_buffer);
+	}
+
+ out:
+	kfree(out_data);
+	kfree(buf);
+	return rc;
+}
+
+
 static long smb3_simple_falloc(struct file *file, struct cifs_tcon *tcon,
 			    loff_t off, loff_t len, bool keep_size)
 {
@@ -3662,6 +3782,26 @@ static long smb3_simple_falloc(struct file *file, struct cifs_tcon *tcon,
 
 	if ((keep_size == true) || (i_size_read(inode) >= off + len)) {
 		/*
+		 * At this point, we are trying to fallocate an internal
+		 * regions of a sparse file. Since smb2 does not have a
+		 * fallocate command we have two otions on how to emulate this.
+		 * We can either turn the entire file to become non-sparse
+		 * which we only do if the fallocate is for virtually
+		 * the whole file,  or we can overwrite the region with zeroes
+		 * using SMB2_write, which could be prohibitevly expensive
+		 * if len is large.
+		 */
+		/*
+		 * We are only trying to fallocate a small region so
+		 * just write it with zero.
+		 */
+		if (len <= 1024 * 1024) {
+			rc = smb3_simple_fallocate_range(xid, tcon, cfile,
+							 off, len);
+			goto out;
+		}
+
+		/*
 		 * Check if falloc starts within first few pages of file
 		 * and ends within a few pages of the end of file to
 		 * ensure that most of file is being forced to be
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index c205f93e0a10..962826dc3316 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/smb2pdu.c
  *
@@ -8,19 +9,6 @@
  *
  *   Contains the routines for constructing the SMB2 PDUs themselves
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
  /* SMB2 PDU handling routines here - except for leftovers (eg session setup) */
@@ -1791,10 +1779,8 @@ SMB2_tcon(const unsigned int xid, struct cifs_ses *ses, const char *tree,
 	rsp = (struct smb2_tree_connect_rsp *)rsp_iov.iov_base;
 	trace_smb3_tcon(xid, tcon->tid, ses->Suid, tree, rc);
 	if (rc != 0) {
-		if (tcon) {
-			cifs_stats_fail_inc(tcon, SMB2_TREE_CONNECT_HE);
-			tcon->need_reconnect = true;
-		}
+		cifs_stats_fail_inc(tcon, SMB2_TREE_CONNECT_HE);
+		tcon->need_reconnect = true;
 		goto tcon_error_exit;
 	}
 
@@ -2906,7 +2892,10 @@ SMB2_open(const unsigned int xid, struct cifs_open_parms *oparms, __le16 *path,
 #endif /* CIFS_DEBUG2 */
 
 	if (buf) {
-		memcpy(buf, &rsp->CreationTime, 32);
+		buf->CreationTime = rsp->CreationTime;
+		buf->LastAccessTime = rsp->LastAccessTime;
+		buf->LastWriteTime = rsp->LastWriteTime;
+		buf->ChangeTime = rsp->ChangeTime;
 		buf->AllocationSize = rsp->AllocationSize;
 		buf->EndOfFile = rsp->EndofFile;
 		buf->Attributes = rsp->FileAttributes;
@@ -3484,6 +3473,8 @@ int SMB2_query_info(const unsigned int xid, struct cifs_tcon *tcon,
 			  NULL);
 }
 
+#if 0
+/* currently unused, as now we are doing compounding instead (see smb311_posix_query_path_info) */
 int
 SMB311_posix_query_info(const unsigned int xid, struct cifs_tcon *tcon,
 		u64 persistent_fid, u64 volatile_fid, struct smb311_posix_qinfo *data, u32 *plen)
@@ -3495,7 +3486,9 @@ SMB311_posix_query_info(const unsigned int xid, struct cifs_tcon *tcon,
 	return query_info(xid, tcon, persistent_fid, volatile_fid,
 			  SMB_FIND_FILE_POSIX_INFO, SMB2_O_INFO_FILE, 0,
 			  output_len, sizeof(struct smb311_posix_qinfo), (void **)&data, plen);
+	/* Note caller must free "data" (passed in above). It may be allocated in query_info call */
 }
+#endif
 
 int
 SMB2_query_acl(const unsigned int xid, struct cifs_tcon *tcon,
@@ -4498,7 +4491,7 @@ int posix_info_parse(const void *beg, const void *end,
 
 {
 	int total_len = 0;
-	int sid_len;
+	int owner_len, group_len;
 	int name_len;
 	const void *owner_sid;
 	const void *group_sid;
@@ -4521,17 +4514,17 @@ int posix_info_parse(const void *beg, const void *end,
 
 	/* check owner sid */
 	owner_sid = beg + total_len;
-	sid_len = posix_info_sid_size(owner_sid, end);
-	if (sid_len < 0)
+	owner_len = posix_info_sid_size(owner_sid, end);
+	if (owner_len < 0)
 		return -1;
-	total_len += sid_len;
+	total_len += owner_len;
 
 	/* check group sid */
 	group_sid = beg + total_len;
-	sid_len = posix_info_sid_size(group_sid, end);
-	if (sid_len < 0)
+	group_len = posix_info_sid_size(group_sid, end);
+	if (group_len < 0)
 		return -1;
-	total_len += sid_len;
+	total_len += group_len;
 
 	/* check name len */
 	if (beg + total_len + 4 > end)
@@ -4552,10 +4545,8 @@ int posix_info_parse(const void *beg, const void *end,
 		out->size = total_len;
 		out->name_len = name_len;
 		out->name = name;
-		memcpy(&out->owner, owner_sid,
-		       posix_info_sid_size(owner_sid, end));
-		memcpy(&out->group, group_sid,
-		       posix_info_sid_size(group_sid, end));
+		memcpy(&out->owner, owner_sid, owner_len);
+		memcpy(&out->group, group_sid, group_len);
 	}
 	return total_len;
 }
diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h
index 6442dc1c292b..a5c48b85549a 100644
--- a/fs/cifs/smb2pdu.h
+++ b/fs/cifs/smb2pdu.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: LGPL-2.1 */
 /*
  *   fs/cifs/smb2pdu.h
  *
@@ -6,19 +7,6 @@
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *              Pavel Shilovsky (pshilovsky@samba.org) 2012
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
 #ifndef _SMB2PDU_H
@@ -276,7 +264,7 @@ struct share_redirect_error_context_rsp {
 	__le32 NotificationType;
 	__le32 ResourceNameOffset;
 	__le32 ResourceNameLength;
-	__le16 Flags;
+	__le16 Reserved;
 	__le16 TargetType;
 	__le32 IPAddrCount;
 	struct move_dst_ipaddr IpAddrMoveList[];
@@ -1460,6 +1448,22 @@ struct smb2_echo_rsp {
 
 #define SMB2_QUERY_DIRECTORY_IOV_SIZE 2
 
+/*
+ * Valid FileInformation classes.
+ *
+ * Note that these are a subset of the (file) QUERY_INFO levels defined
+ * later in this file (but since QUERY_DIRECTORY uses equivalent numbers
+ * we do not redefine them here)
+ *
+ * FileDirectoryInfomation		0x01
+ * FileFullDirectoryInformation		0x02
+ * FileIdFullDirectoryInformation	0x26
+ * FileBothDirectoryInformation		0x03
+ * FileIdBothDirectoryInformation	0x25
+ * FileNamesInformation			0x0C
+ * FileIdExtdDirectoryInformation	0x3C
+ */
+
 struct smb2_query_directory_req {
 	struct smb2_sync_hdr sync_hdr;
 	__le16 StructureSize; /* Must be 33 */
@@ -1696,6 +1700,7 @@ struct smb3_fs_vol_info {
 #define FILEID_GLOBAL_TX_DIRECTORY_INFORMATION 50
 #define FILE_STANDARD_LINK_INFORMATION	54
 #define FILE_ID_INFORMATION		59
+#define FILE_ID_EXTD_DIRECTORY_INFORMATION 60
 
 struct smb2_file_internal_info {
 	__le64 IndexNumber;
@@ -1776,13 +1781,31 @@ struct smb2_file_network_open_info {
 	__le32 Reserved;
 } __packed; /* level 34 Query also similar returned in close rsp and open rsp */
 
-/* See MS-FSCC 2.4.43 */
+/* See MS-FSCC 2.4.21 */
 struct smb2_file_id_information {
 	__le64	VolumeSerialNumber;
 	__u64  PersistentFileId; /* opaque endianness */
 	__u64  VolatileFileId; /* opaque endianness */
 } __packed; /* level 59 */
 
+/* See MS-FSCC 2.4.18 */
+struct smb2_file_id_extd_directory_info {
+	__le32 NextEntryOffset;
+	__u32 FileIndex;
+	__le64 CreationTime;
+	__le64 LastAccessTime;
+	__le64 LastWriteTime;
+	__le64 ChangeTime;
+	__le64 EndOfFile;
+	__le64 AllocationSize;
+	__le32 FileAttributes;
+	__le32 FileNameLength;
+	__le32 EaSize; /* EA size */
+	__le32 ReparsePointTag; /* valid if FILE_ATTR_REPARSE_POINT set in FileAttributes */
+	__le64 UniqueId; /* inode num - le since Samba puts ino in low 32 bit */
+	char FileName[1];
+} __packed; /* level 60 */
+
 extern char smb2_padding[7];
 
 /* equivalent of the contents of SMB3.1.1 POSIX open context response */
diff --git a/fs/cifs/smb2proto.h b/fs/cifs/smb2proto.h
index a5f87b02cfaf..263767f644f8 100644
--- a/fs/cifs/smb2proto.h
+++ b/fs/cifs/smb2proto.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: LGPL-2.1 */
 /*
  *   fs/cifs/smb2proto.h
  *
@@ -6,19 +7,6 @@
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *              Pavel Shilovsky (pshilovsky@samba.org) 2012
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 #ifndef _SMB2PROTO_H
 #define _SMB2PROTO_H
@@ -64,8 +52,6 @@ extern void smb2_echo_request(struct work_struct *work);
 extern __le32 smb2_get_lease_state(struct cifsInodeInfo *cinode);
 extern bool smb2_is_valid_oplock_break(char *buffer,
 				       struct TCP_Server_Info *srv);
-extern struct cifs_ses *smb2_find_smb_ses(struct TCP_Server_Info *server,
-					  __u64 ses_id);
 extern int smb3_handle_read_data(struct TCP_Server_Info *server,
 				 struct mid_q_entry *mid);
 
diff --git a/fs/cifs/smb2status.h b/fs/cifs/smb2status.h
index 7505056e9580..0215ef36e240 100644
--- a/fs/cifs/smb2status.h
+++ b/fs/cifs/smb2status.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: LGPL-2.1 */
 /*
  *   fs/cifs/smb2status.h
  *
@@ -7,19 +8,6 @@
  *   Copyright (c) International Business Machines  Corp., 2009,2011
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
 /*
diff --git a/fs/cifs/smb2transport.c b/fs/cifs/smb2transport.c
index e6fa76ab70be..6f7952ea4941 100644
--- a/fs/cifs/smb2transport.c
+++ b/fs/cifs/smb2transport.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/smb2transport.c
  *
@@ -7,19 +8,6 @@
  *              Jeremy Allison (jra@samba.org) 2006
  *              Pavel Shilovsky (pshilovsky@samba.org) 2012
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
 #include <linux/fs.h>
@@ -154,6 +142,7 @@ smb2_find_smb_ses_unlocked(struct TCP_Server_Info *server, __u64 ses_id)
 	list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
 		if (ses->Suid != ses_id)
 			continue;
+		++ses->ses_count;
 		return ses;
 	}
 
@@ -205,7 +194,14 @@ smb2_find_smb_tcon(struct TCP_Server_Info *server, __u64 ses_id, __u32  tid)
 		return NULL;
 	}
 	tcon = smb2_find_smb_sess_tcon_unlocked(ses, tid);
+	if (!tcon) {
+		cifs_put_smb_ses(ses);
+		spin_unlock(&cifs_tcp_ses_lock);
+		return NULL;
+	}
 	spin_unlock(&cifs_tcp_ses_lock);
+	/* tcon already has a ref to ses, so we don't need ses anymore */
+	cifs_put_smb_ses(ses);
 
 	return tcon;
 }
@@ -239,7 +235,7 @@ smb2_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server,
 		if (rc) {
 			cifs_server_dbg(VFS,
 					"%s: sha256 alloc failed\n", __func__);
-			return rc;
+			goto out;
 		}
 		shash = &sdesc->shash;
 	} else {
@@ -290,6 +286,8 @@ smb2_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server,
 out:
 	if (allocate_crypto)
 		cifs_free_hash(&hash, &sdesc);
+	if (ses)
+		cifs_put_smb_ses(ses);
 	return rc;
 }
 
diff --git a/fs/cifs/smbdirect.c b/fs/cifs/smbdirect.c
index 10dfe5006792..31ef64eb7fbb 100644
--- a/fs/cifs/smbdirect.c
+++ b/fs/cifs/smbdirect.c
@@ -572,8 +572,13 @@ static struct rdma_cm_id *smbd_create_id(
 		log_rdma_event(ERR, "rdma_resolve_addr() failed %i\n", rc);
 		goto out;
 	}
-	wait_for_completion_interruptible_timeout(
+	rc = wait_for_completion_interruptible_timeout(
 		&info->ri_done, msecs_to_jiffies(RDMA_RESOLVE_TIMEOUT));
+	/* e.g. if interrupted returns -ERESTARTSYS */
+	if (rc < 0) {
+		log_rdma_event(ERR, "rdma_resolve_addr timeout rc: %i\n", rc);
+		goto out;
+	}
 	rc = info->ri_rc;
 	if (rc) {
 		log_rdma_event(ERR, "rdma_resolve_addr() completed %i\n", rc);
@@ -586,8 +591,13 @@ static struct rdma_cm_id *smbd_create_id(
 		log_rdma_event(ERR, "rdma_resolve_route() failed %i\n", rc);
 		goto out;
 	}
-	wait_for_completion_interruptible_timeout(
+	rc = wait_for_completion_interruptible_timeout(
 		&info->ri_done, msecs_to_jiffies(RDMA_RESOLVE_TIMEOUT));
+	/* e.g. if interrupted returns -ERESTARTSYS */
+	if (rc < 0)  {
+		log_rdma_event(ERR, "rdma_resolve_addr timeout rc: %i\n", rc);
+		goto out;
+	}
 	rc = info->ri_rc;
 	if (rc) {
 		log_rdma_event(ERR, "rdma_resolve_route() completed %i\n", rc);
diff --git a/fs/cifs/smberr.h b/fs/cifs/smberr.h
index 7f16cb825fe5..60189efb3236 100644
--- a/fs/cifs/smberr.h
+++ b/fs/cifs/smberr.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: LGPL-2.1 */
 /*
  *   fs/cifs/smberr.h
  *
@@ -7,19 +8,6 @@
  *   See Error Codes section of the SNIA CIFS Specification
  *   for more information
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
 #define SUCCESS	0x00	/* The request was successful. */
diff --git a/fs/cifs/smbfsctl.h b/fs/cifs/smbfsctl.h
index a0e84747f567..d0fc42061f49 100644
--- a/fs/cifs/smbfsctl.h
+++ b/fs/cifs/smbfsctl.h
@@ -1,22 +1,10 @@
+/* SPDX-License-Identifier: LGPL-2.1 */
 /*
  *   fs/cifs/smbfsctl.h: SMB, CIFS, SMB2 FSCTL definitions
  *
  *   Copyright (c) International Business Machines  Corp., 2002,2013
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
 /* IOCTL information */
diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
index c1725b55f364..f65f9a692ca2 100644
--- a/fs/cifs/transport.c
+++ b/fs/cifs/transport.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/transport.c
  *
@@ -5,19 +6,6 @@
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *   Jeremy Allison (jra@samba.org) 2006.
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
 #include <linux/fs.h>
diff --git a/fs/cifs/xattr.c b/fs/cifs/xattr.c
index aa3e8ca0457c..9ed481e79ce0 100644
--- a/fs/cifs/xattr.c
+++ b/fs/cifs/xattr.c
@@ -1,22 +1,10 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/xattr.c
  *
  *   Copyright (c) International Business Machines  Corp., 2003, 2007
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library 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 Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
 #include <linux/fs.h>