Backmerge tag 'v6.4-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into drm-next

Linux 6.4-rc7

Need this to pull in the msm work.

Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 1854 insertions, 0 deletions

diff --git a/fs/smb/client/cifsfs.c b/fs/smb/client/cifsfs.c
new file mode 100644
index 000000000000..43a4d8603db3
--- /dev/null
+++ b/fs/smb/client/cifsfs.c
@@ -0,0 +1,1854 @@
+// SPDX-License-Identifier: LGPL-2.1
+/*
+ *
+ *   Copyright (C) International Business Machines  Corp., 2002,2008
+ *   Author(s): Steve French (sfrench@us.ibm.com)
+ *
+ *   Common Internet FileSystem (CIFS) client
+ *
+ */
+
+/* Note that BB means BUGBUG (ie something to fix eventually) */
+
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/filelock.h>
+#include <linux/mount.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/seq_file.h>
+#include <linux/vfs.h>
+#include <linux/mempool.h>
+#include <linux/delay.h>
+#include <linux/kthread.h>
+#include <linux/freezer.h>
+#include <linux/namei.h>
+#include <linux/random.h>
+#include <linux/uuid.h>
+#include <linux/xattr.h>
+#include <uapi/linux/magic.h>
+#include <net/ipv6.h>
+#include "cifsfs.h"
+#include "cifspdu.h"
+#define DECLARE_GLOBALS_HERE
+#include "cifsglob.h"
+#include "cifsproto.h"
+#include "cifs_debug.h"
+#include "cifs_fs_sb.h"
+#include <linux/mm.h>
+#include <linux/key-type.h>
+#include "cifs_spnego.h"
+#include "fscache.h"
+#ifdef CONFIG_CIFS_DFS_UPCALL
+#include "dfs_cache.h"
+#endif
+#ifdef CONFIG_CIFS_SWN_UPCALL
+#include "netlink.h"
+#endif
+#include "fs_context.h"
+#include "cached_dir.h"
+
+/*
+ * DOS dates from 1980/1/1 through 2107/12/31
+ * Protocol specifications indicate the range should be to 119, which
+ * limits maximum year to 2099. But this range has not been checked.
+ */
+#define SMB_DATE_MAX (127<<9 | 12<<5 | 31)
+#define SMB_DATE_MIN (0<<9 | 1<<5 | 1)
+#define SMB_TIME_MAX (23<<11 | 59<<5 | 29)
+
+int cifsFYI = 0;
+bool traceSMB;
+bool enable_oplocks = true;
+bool linuxExtEnabled = true;
+bool lookupCacheEnabled = true;
+bool disable_legacy_dialects; /* false by default */
+bool enable_gcm_256 = true;
+bool require_gcm_256; /* false by default */
+bool enable_negotiate_signing; /* false by default */
+unsigned int global_secflags = CIFSSEC_DEF;
+/* unsigned int ntlmv2_support = 0; */
+unsigned int sign_CIFS_PDUs = 1;
+
+/*
+ * Global transaction id (XID) information
+ */
+unsigned int GlobalCurrentXid;	/* protected by GlobalMid_Sem */
+unsigned int GlobalTotalActiveXid; /* prot by GlobalMid_Sem */
+unsigned int GlobalMaxActiveXid;	/* prot by GlobalMid_Sem */
+spinlock_t GlobalMid_Lock; /* protects above & list operations on midQ entries */
+
+/*
+ *  Global counters, updated atomically
+ */
+atomic_t sesInfoAllocCount;
+atomic_t tconInfoAllocCount;
+atomic_t tcpSesNextId;
+atomic_t tcpSesAllocCount;
+atomic_t tcpSesReconnectCount;
+atomic_t tconInfoReconnectCount;
+
+atomic_t mid_count;
+atomic_t buf_alloc_count;
+atomic_t small_buf_alloc_count;
+#ifdef CONFIG_CIFS_STATS2
+atomic_t total_buf_alloc_count;
+atomic_t total_small_buf_alloc_count;
+#endif/* STATS2 */
+struct list_head	cifs_tcp_ses_list;
+spinlock_t		cifs_tcp_ses_lock;
+static const struct super_operations cifs_super_ops;
+unsigned int CIFSMaxBufSize = CIFS_MAX_MSGSIZE;
+module_param(CIFSMaxBufSize, uint, 0444);
+MODULE_PARM_DESC(CIFSMaxBufSize, "Network buffer size (not including header) "
+				 "for CIFS requests. "
+				 "Default: 16384 Range: 8192 to 130048");
+unsigned int cifs_min_rcv = CIFS_MIN_RCV_POOL;
+module_param(cifs_min_rcv, uint, 0444);
+MODULE_PARM_DESC(cifs_min_rcv, "Network buffers in pool. Default: 4 Range: "
+				"1 to 64");
+unsigned int cifs_min_small = 30;
+module_param(cifs_min_small, uint, 0444);
+MODULE_PARM_DESC(cifs_min_small, "Small network buffers in pool. Default: 30 "
+				 "Range: 2 to 256");
+unsigned int cifs_max_pending = CIFS_MAX_REQ;
+module_param(cifs_max_pending, uint, 0444);
+MODULE_PARM_DESC(cifs_max_pending, "Simultaneous requests to server for "
+				   "CIFS/SMB1 dialect (N/A for SMB3) "
+				   "Default: 32767 Range: 2 to 32767.");
+#ifdef CONFIG_CIFS_STATS2
+unsigned int slow_rsp_threshold = 1;
+module_param(slow_rsp_threshold, uint, 0644);
+MODULE_PARM_DESC(slow_rsp_threshold, "Amount of time (in seconds) to wait "
+				   "before logging that a response is delayed. "
+				   "Default: 1 (if set to 0 disables msg).");
+#endif /* STATS2 */
+
+module_param(enable_oplocks, bool, 0644);
+MODULE_PARM_DESC(enable_oplocks, "Enable or disable oplocks. Default: y/Y/1");
+
+module_param(enable_gcm_256, bool, 0644);
+MODULE_PARM_DESC(enable_gcm_256, "Enable requesting strongest (256 bit) GCM encryption. Default: n/N/0");
+
+module_param(require_gcm_256, bool, 0644);
+MODULE_PARM_DESC(require_gcm_256, "Require strongest (256 bit) GCM encryption. Default: n/N/0");
+
+module_param(enable_negotiate_signing, bool, 0644);
+MODULE_PARM_DESC(enable_negotiate_signing, "Enable negotiating packet signing algorithm with server. Default: n/N/0");
+
+module_param(disable_legacy_dialects, bool, 0644);
+MODULE_PARM_DESC(disable_legacy_dialects, "To improve security it may be "
+				  "helpful to restrict the ability to "
+				  "override the default dialects (SMB2.1, "
+				  "SMB3 and SMB3.02) on mount with old "
+				  "dialects (CIFS/SMB1 and SMB2) since "
+				  "vers=1.0 (CIFS/SMB1) and vers=2.0 are weaker"
+				  " and less secure. Default: n/N/0");
+
+extern mempool_t *cifs_sm_req_poolp;
+extern mempool_t *cifs_req_poolp;
+extern mempool_t *cifs_mid_poolp;
+
+struct workqueue_struct	*cifsiod_wq;
+struct workqueue_struct	*decrypt_wq;
+struct workqueue_struct	*fileinfo_put_wq;
+struct workqueue_struct	*cifsoplockd_wq;
+struct workqueue_struct	*deferredclose_wq;
+__u32 cifs_lock_secret;
+
+/*
+ * Bumps refcount for cifs super block.
+ * Note that it should be only called if a referece to VFS super block is
+ * already held, e.g. in open-type syscalls context. Otherwise it can race with
+ * atomic_dec_and_test in deactivate_locked_super.
+ */
+void
+cifs_sb_active(struct super_block *sb)
+{
+	struct cifs_sb_info *server = CIFS_SB(sb);
+
+	if (atomic_inc_return(&server->active) == 1)
+		atomic_inc(&sb->s_active);
+}
+
+void
+cifs_sb_deactive(struct super_block *sb)
+{
+	struct cifs_sb_info *server = CIFS_SB(sb);
+
+	if (atomic_dec_and_test(&server->active))
+		deactivate_super(sb);
+}
+
+static int
+cifs_read_super(struct super_block *sb)
+{
+	struct inode *inode;
+	struct cifs_sb_info *cifs_sb;
+	struct cifs_tcon *tcon;
+	struct timespec64 ts;
+	int rc = 0;
+
+	cifs_sb = CIFS_SB(sb);
+	tcon = cifs_sb_master_tcon(cifs_sb);
+
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIXACL)
+		sb->s_flags |= SB_POSIXACL;
+
+	if (tcon->snapshot_time)
+		sb->s_flags |= SB_RDONLY;
+
+	if (tcon->ses->capabilities & tcon->ses->server->vals->cap_large_files)
+		sb->s_maxbytes = MAX_LFS_FILESIZE;
+	else
+		sb->s_maxbytes = MAX_NON_LFS;
+
+	/*
+	 * Some very old servers like DOS and OS/2 used 2 second granularity
+	 * (while all current servers use 100ns granularity - see MS-DTYP)
+	 * but 1 second is the maximum allowed granularity for the VFS
+	 * so for old servers set time granularity to 1 second while for
+	 * everything else (current servers) set it to 100ns.
+	 */
+	if ((tcon->ses->server->vals->protocol_id == SMB10_PROT_ID) &&
+	    ((tcon->ses->capabilities &
+	      tcon->ses->server->vals->cap_nt_find) == 0) &&
+	    !tcon->unix_ext) {
+		sb->s_time_gran = 1000000000; /* 1 second is max allowed gran */
+		ts = cnvrtDosUnixTm(cpu_to_le16(SMB_DATE_MIN), 0, 0);
+		sb->s_time_min = ts.tv_sec;
+		ts = cnvrtDosUnixTm(cpu_to_le16(SMB_DATE_MAX),
+				    cpu_to_le16(SMB_TIME_MAX), 0);
+		sb->s_time_max = ts.tv_sec;
+	} else {
+		/*
+		 * Almost every server, including all SMB2+, uses DCE TIME
+		 * ie 100 nanosecond units, since 1601.  See MS-DTYP and MS-FSCC
+		 */
+		sb->s_time_gran = 100;
+		ts = cifs_NTtimeToUnix(0);
+		sb->s_time_min = ts.tv_sec;
+		ts = cifs_NTtimeToUnix(cpu_to_le64(S64_MAX));
+		sb->s_time_max = ts.tv_sec;
+	}
+
+	sb->s_magic = CIFS_SUPER_MAGIC;
+	sb->s_op = &cifs_super_ops;
+	sb->s_xattr = cifs_xattr_handlers;
+	rc = super_setup_bdi(sb);
+	if (rc)
+		goto out_no_root;
+	/* tune readahead according to rsize if readahead size not set on mount */
+	if (cifs_sb->ctx->rsize == 0)
+		cifs_sb->ctx->rsize =
+			tcon->ses->server->ops->negotiate_rsize(tcon, cifs_sb->ctx);
+	if (cifs_sb->ctx->rasize)
+		sb->s_bdi->ra_pages = cifs_sb->ctx->rasize / PAGE_SIZE;
+	else
+		sb->s_bdi->ra_pages = 2 * (cifs_sb->ctx->rsize / PAGE_SIZE);
+
+	sb->s_blocksize = CIFS_MAX_MSGSIZE;
+	sb->s_blocksize_bits = 14;	/* default 2**14 = CIFS_MAX_MSGSIZE */
+	inode = cifs_root_iget(sb);
+
+	if (IS_ERR(inode)) {
+		rc = PTR_ERR(inode);
+		goto out_no_root;
+	}
+
+	if (tcon->nocase)
+		sb->s_d_op = &cifs_ci_dentry_ops;
+	else
+		sb->s_d_op = &cifs_dentry_ops;
+
+	sb->s_root = d_make_root(inode);
+	if (!sb->s_root) {
+		rc = -ENOMEM;
+		goto out_no_root;
+	}
+
+#ifdef CONFIG_CIFS_NFSD_EXPORT
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {
+		cifs_dbg(FYI, "export ops supported\n");
+		sb->s_export_op = &cifs_export_ops;
+	}
+#endif /* CONFIG_CIFS_NFSD_EXPORT */
+
+	return 0;
+
+out_no_root:
+	cifs_dbg(VFS, "%s: get root inode failed\n", __func__);
+	return rc;
+}
+
+static void cifs_kill_sb(struct super_block *sb)
+{
+	struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
+
+	/*
+	 * We ned to release all dentries for the cached directories
+	 * before we kill the sb.
+	 */
+	if (cifs_sb->root) {
+		close_all_cached_dirs(cifs_sb);
+
+		/* finally release root dentry */
+		dput(cifs_sb->root);
+		cifs_sb->root = NULL;
+	}
+
+	kill_anon_super(sb);
+	cifs_umount(cifs_sb);
+}
+
+static int
+cifs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+	struct super_block *sb = dentry->d_sb;
+	struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
+	struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
+	struct TCP_Server_Info *server = tcon->ses->server;
+	unsigned int xid;
+	int rc = 0;
+
+	xid = get_xid();
+
+	if (le32_to_cpu(tcon->fsAttrInfo.MaxPathNameComponentLength) > 0)
+		buf->f_namelen =
+		       le32_to_cpu(tcon->fsAttrInfo.MaxPathNameComponentLength);
+	else
+		buf->f_namelen = PATH_MAX;
+
+	buf->f_fsid.val[0] = tcon->vol_serial_number;
+	/* are using part of create time for more randomness, see man statfs */
+	buf->f_fsid.val[1] =  (int)le64_to_cpu(tcon->vol_create_time);
+
+	buf->f_files = 0;	/* undefined */
+	buf->f_ffree = 0;	/* unlimited */
+
+	if (server->ops->queryfs)
+		rc = server->ops->queryfs(xid, tcon, cifs_sb, buf);
+
+	free_xid(xid);
+	return rc;
+}
+
+static long cifs_fallocate(struct file *file, int mode, loff_t off, loff_t len)
+{
+	struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file);
+	struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
+	struct TCP_Server_Info *server = tcon->ses->server;
+
+	if (server->ops->fallocate)
+		return server->ops->fallocate(file, tcon, mode, off, len);
+
+	return -EOPNOTSUPP;
+}
+
+static int cifs_permission(struct mnt_idmap *idmap,
+			   struct inode *inode, int mask)
+{
+	struct cifs_sb_info *cifs_sb;
+
+	cifs_sb = CIFS_SB(inode->i_sb);
+
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_PERM) {
+		if ((mask & MAY_EXEC) && !execute_ok(inode))
+			return -EACCES;
+		else
+			return 0;
+	} else /* file mode might have been restricted at mount time
+		on the client (above and beyond ACL on servers) for
+		servers which do not support setting and viewing mode bits,
+		so allowing client to check permissions is useful */
+		return generic_permission(&nop_mnt_idmap, inode, mask);
+}
+
+static struct kmem_cache *cifs_inode_cachep;
+static struct kmem_cache *cifs_req_cachep;
+static struct kmem_cache *cifs_mid_cachep;
+static struct kmem_cache *cifs_sm_req_cachep;
+mempool_t *cifs_sm_req_poolp;
+mempool_t *cifs_req_poolp;
+mempool_t *cifs_mid_poolp;
+
+static struct inode *
+cifs_alloc_inode(struct super_block *sb)
+{
+	struct cifsInodeInfo *cifs_inode;
+	cifs_inode = alloc_inode_sb(sb, cifs_inode_cachep, GFP_KERNEL);
+	if (!cifs_inode)
+		return NULL;
+	cifs_inode->cifsAttrs = 0x20;	/* default */
+	cifs_inode->time = 0;
+	/*
+	 * Until the file is open and we have gotten oplock info back from the
+	 * server, can not assume caching of file data or metadata.
+	 */
+	cifs_set_oplock_level(cifs_inode, 0);
+	cifs_inode->flags = 0;
+	spin_lock_init(&cifs_inode->writers_lock);
+	cifs_inode->writers = 0;
+	cifs_inode->netfs.inode.i_blkbits = 14;  /* 2**14 = CIFS_MAX_MSGSIZE */
+	cifs_inode->server_eof = 0;
+	cifs_inode->uniqueid = 0;
+	cifs_inode->createtime = 0;
+	cifs_inode->epoch = 0;
+	spin_lock_init(&cifs_inode->open_file_lock);
+	generate_random_uuid(cifs_inode->lease_key);
+	cifs_inode->symlink_target = NULL;
+
+	/*
+	 * Can not set i_flags here - they get immediately overwritten to zero
+	 * by the VFS.
+	 */
+	/* cifs_inode->netfs.inode.i_flags = S_NOATIME | S_NOCMTIME; */
+	INIT_LIST_HEAD(&cifs_inode->openFileList);
+	INIT_LIST_HEAD(&cifs_inode->llist);
+	INIT_LIST_HEAD(&cifs_inode->deferred_closes);
+	spin_lock_init(&cifs_inode->deferred_lock);
+	return &cifs_inode->netfs.inode;
+}
+
+static void
+cifs_free_inode(struct inode *inode)
+{
+	struct cifsInodeInfo *cinode = CIFS_I(inode);
+
+	if (S_ISLNK(inode->i_mode))
+		kfree(cinode->symlink_target);
+	kmem_cache_free(cifs_inode_cachep, cinode);
+}
+
+static void
+cifs_evict_inode(struct inode *inode)
+{
+	truncate_inode_pages_final(&inode->i_data);
+	if (inode->i_state & I_PINNING_FSCACHE_WB)
+		cifs_fscache_unuse_inode_cookie(inode, true);
+	cifs_fscache_release_inode_cookie(inode);
+	clear_inode(inode);
+}
+
+static void
+cifs_show_address(struct seq_file *s, struct TCP_Server_Info *server)
+{
+	struct sockaddr_in *sa = (struct sockaddr_in *) &server->dstaddr;
+	struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *) &server->dstaddr;
+
+	seq_puts(s, ",addr=");
+
+	switch (server->dstaddr.ss_family) {
+	case AF_INET:
+		seq_printf(s, "%pI4", &sa->sin_addr.s_addr);
+		break;
+	case AF_INET6:
+		seq_printf(s, "%pI6", &sa6->sin6_addr.s6_addr);
+		if (sa6->sin6_scope_id)
+			seq_printf(s, "%%%u", sa6->sin6_scope_id);
+		break;
+	default:
+		seq_puts(s, "(unknown)");
+	}
+	if (server->rdma)
+		seq_puts(s, ",rdma");
+}
+
+static void
+cifs_show_security(struct seq_file *s, struct cifs_ses *ses)
+{
+	if (ses->sectype == Unspecified) {
+		if (ses->user_name == NULL)
+			seq_puts(s, ",sec=none");
+		return;
+	}
+
+	seq_puts(s, ",sec=");
+
+	switch (ses->sectype) {
+	case NTLMv2:
+		seq_puts(s, "ntlmv2");
+		break;
+	case Kerberos:
+		seq_puts(s, "krb5");
+		break;
+	case RawNTLMSSP:
+		seq_puts(s, "ntlmssp");
+		break;
+	default:
+		/* shouldn't ever happen */
+		seq_puts(s, "unknown");
+		break;
+	}
+
+	if (ses->sign)
+		seq_puts(s, "i");
+
+	if (ses->sectype == Kerberos)
+		seq_printf(s, ",cruid=%u",
+			   from_kuid_munged(&init_user_ns, ses->cred_uid));
+}
+
+static void
+cifs_show_cache_flavor(struct seq_file *s, struct cifs_sb_info *cifs_sb)
+{
+	seq_puts(s, ",cache=");
+
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO)
+		seq_puts(s, "strict");
+	else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DIRECT_IO)
+		seq_puts(s, "none");
+	else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RW_CACHE)
+		seq_puts(s, "singleclient"); /* assume only one client access */
+	else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RO_CACHE)
+		seq_puts(s, "ro"); /* read only caching assumed */
+	else
+		seq_puts(s, "loose");
+}
+
+/*
+ * cifs_show_devname() is used so we show the mount device name with correct
+ * format (e.g. forward slashes vs. back slashes) in /proc/mounts
+ */
+static int cifs_show_devname(struct seq_file *m, struct dentry *root)
+{
+	struct cifs_sb_info *cifs_sb = CIFS_SB(root->d_sb);
+	char *devname = kstrdup(cifs_sb->ctx->source, GFP_KERNEL);
+
+	if (devname == NULL)
+		seq_puts(m, "none");
+	else {
+		convert_delimiter(devname, '/');
+		/* escape all spaces in share names */
+		seq_escape(m, devname, " \t");
+		kfree(devname);
+	}
+	return 0;
+}
+
+/*
+ * cifs_show_options() is for displaying mount options in /proc/mounts.
+ * Not all settable options are displayed but most of the important
+ * ones are.
+ */
+static int
+cifs_show_options(struct seq_file *s, struct dentry *root)
+{
+	struct cifs_sb_info *cifs_sb = CIFS_SB(root->d_sb);
+	struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
+	struct sockaddr *srcaddr;
+	srcaddr = (struct sockaddr *)&tcon->ses->server->srcaddr;
+
+	seq_show_option(s, "vers", tcon->ses->server->vals->version_string);
+	cifs_show_security(s, tcon->ses);
+	cifs_show_cache_flavor(s, cifs_sb);
+
+	if (tcon->no_lease)
+		seq_puts(s, ",nolease");
+	if (cifs_sb->ctx->multiuser)
+		seq_puts(s, ",multiuser");
+	else if (tcon->ses->user_name)
+		seq_show_option(s, "username", tcon->ses->user_name);
+
+	if (tcon->ses->domainName && tcon->ses->domainName[0] != 0)
+		seq_show_option(s, "domain", tcon->ses->domainName);
+
+	if (srcaddr->sa_family != AF_UNSPEC) {
+		struct sockaddr_in *saddr4;
+		struct sockaddr_in6 *saddr6;
+		saddr4 = (struct sockaddr_in *)srcaddr;
+		saddr6 = (struct sockaddr_in6 *)srcaddr;
+		if (srcaddr->sa_family == AF_INET6)
+			seq_printf(s, ",srcaddr=%pI6c",
+				   &saddr6->sin6_addr);
+		else if (srcaddr->sa_family == AF_INET)
+			seq_printf(s, ",srcaddr=%pI4",
+				   &saddr4->sin_addr.s_addr);
+		else
+			seq_printf(s, ",srcaddr=BAD-AF:%i",
+				   (int)(srcaddr->sa_family));
+	}
+
+	seq_printf(s, ",uid=%u",
+		   from_kuid_munged(&init_user_ns, cifs_sb->ctx->linux_uid));
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_OVERR_UID)
+		seq_puts(s, ",forceuid");
+	else
+		seq_puts(s, ",noforceuid");
+
+	seq_printf(s, ",gid=%u",
+		   from_kgid_munged(&init_user_ns, cifs_sb->ctx->linux_gid));
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_OVERR_GID)
+		seq_puts(s, ",forcegid");
+	else
+		seq_puts(s, ",noforcegid");
+
+	cifs_show_address(s, tcon->ses->server);
+
+	if (!tcon->unix_ext)
+		seq_printf(s, ",file_mode=0%ho,dir_mode=0%ho",
+					   cifs_sb->ctx->file_mode,
+					   cifs_sb->ctx->dir_mode);
+	if (cifs_sb->ctx->iocharset)
+		seq_printf(s, ",iocharset=%s", cifs_sb->ctx->iocharset);
+	if (tcon->seal)
+		seq_puts(s, ",seal");
+	else if (tcon->ses->server->ignore_signature)
+		seq_puts(s, ",signloosely");
+	if (tcon->nocase)
+		seq_puts(s, ",nocase");
+	if (tcon->nodelete)
+		seq_puts(s, ",nodelete");
+	if (cifs_sb->ctx->no_sparse)
+		seq_puts(s, ",nosparse");
+	if (tcon->local_lease)
+		seq_puts(s, ",locallease");
+	if (tcon->retry)
+		seq_puts(s, ",hard");
+	else
+		seq_puts(s, ",soft");
+	if (tcon->use_persistent)
+		seq_puts(s, ",persistenthandles");
+	else if (tcon->use_resilient)
+		seq_puts(s, ",resilienthandles");
+	if (tcon->posix_extensions)
+		seq_puts(s, ",posix");
+	else if (tcon->unix_ext)
+		seq_puts(s, ",unix");
+	else
+		seq_puts(s, ",nounix");
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_DFS)
+		seq_puts(s, ",nodfs");
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS)
+		seq_puts(s, ",posixpaths");
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID)
+		seq_puts(s, ",setuids");
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UID_FROM_ACL)
+		seq_puts(s, ",idsfromsid");
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)
+		seq_puts(s, ",serverino");
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
+		seq_puts(s, ",rwpidforward");
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL)
+		seq_puts(s, ",forcemand");
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
+		seq_puts(s, ",nouser_xattr");
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR)
+		seq_puts(s, ",mapchars");
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SFM_CHR)
+		seq_puts(s, ",mapposix");
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL)
+		seq_puts(s, ",sfu");
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
+		seq_puts(s, ",nobrl");
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_HANDLE_CACHE)
+		seq_puts(s, ",nohandlecache");
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MODE_FROM_SID)
+		seq_puts(s, ",modefromsid");
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_ACL)
+		seq_puts(s, ",cifsacl");
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DYNPERM)
+		seq_puts(s, ",dynperm");
+	if (root->d_sb->s_flags & SB_POSIXACL)
+		seq_puts(s, ",acl");
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS)
+		seq_puts(s, ",mfsymlinks");
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_FSCACHE)
+		seq_puts(s, ",fsc");
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC)
+		seq_puts(s, ",nostrictsync");
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_PERM)
+		seq_puts(s, ",noperm");
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPUID)
+		seq_printf(s, ",backupuid=%u",
+			   from_kuid_munged(&init_user_ns,
+					    cifs_sb->ctx->backupuid));
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPGID)
+		seq_printf(s, ",backupgid=%u",
+			   from_kgid_munged(&init_user_ns,
+					    cifs_sb->ctx->backupgid));
+
+	seq_printf(s, ",rsize=%u", cifs_sb->ctx->rsize);
+	seq_printf(s, ",wsize=%u", cifs_sb->ctx->wsize);
+	seq_printf(s, ",bsize=%u", cifs_sb->ctx->bsize);
+	if (cifs_sb->ctx->rasize)
+		seq_printf(s, ",rasize=%u", cifs_sb->ctx->rasize);
+	if (tcon->ses->server->min_offload)
+		seq_printf(s, ",esize=%u", tcon->ses->server->min_offload);
+	seq_printf(s, ",echo_interval=%lu",
+			tcon->ses->server->echo_interval / HZ);
+
+	/* Only display the following if overridden on mount */
+	if (tcon->ses->server->max_credits != SMB2_MAX_CREDITS_AVAILABLE)
+		seq_printf(s, ",max_credits=%u", tcon->ses->server->max_credits);
+	if (tcon->ses->server->tcp_nodelay)
+		seq_puts(s, ",tcpnodelay");
+	if (tcon->ses->server->noautotune)
+		seq_puts(s, ",noautotune");
+	if (tcon->ses->server->noblocksnd)
+		seq_puts(s, ",noblocksend");
+
+	if (tcon->snapshot_time)
+		seq_printf(s, ",snapshot=%llu", tcon->snapshot_time);
+	if (tcon->handle_timeout)
+		seq_printf(s, ",handletimeout=%u", tcon->handle_timeout);
+
+	/*
+	 * Display file and directory attribute timeout in seconds.
+	 * If file and directory attribute timeout the same then actimeo
+	 * was likely specified on mount
+	 */
+	if (cifs_sb->ctx->acdirmax == cifs_sb->ctx->acregmax)
+		seq_printf(s, ",actimeo=%lu", cifs_sb->ctx->acregmax / HZ);
+	else {
+		seq_printf(s, ",acdirmax=%lu", cifs_sb->ctx->acdirmax / HZ);
+		seq_printf(s, ",acregmax=%lu", cifs_sb->ctx->acregmax / HZ);
+	}
+	seq_printf(s, ",closetimeo=%lu", cifs_sb->ctx->closetimeo / HZ);
+
+	if (tcon->ses->chan_max > 1)
+		seq_printf(s, ",multichannel,max_channels=%zu",
+			   tcon->ses->chan_max);
+
+	if (tcon->use_witness)
+		seq_puts(s, ",witness");
+
+	return 0;
+}
+
+static void cifs_umount_begin(struct super_block *sb)
+{
+	struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
+	struct cifs_tcon *tcon;
+
+	if (cifs_sb == NULL)
+		return;
+
+	tcon = cifs_sb_master_tcon(cifs_sb);
+
+	spin_lock(&cifs_tcp_ses_lock);
+	spin_lock(&tcon->tc_lock);
+	if ((tcon->tc_count > 1) || (tcon->status == TID_EXITING)) {
+		/* we have other mounts to same share or we have
+		   already tried to umount this and woken up
+		   all waiting network requests, nothing to do */
+		spin_unlock(&tcon->tc_lock);
+		spin_unlock(&cifs_tcp_ses_lock);
+		return;
+	}
+	/*
+	 * can not set tcon->status to TID_EXITING yet since we don't know if umount -f will
+	 * fail later (e.g. due to open files).  TID_EXITING will be set just before tdis req sent
+	 */
+	spin_unlock(&tcon->tc_lock);
+	spin_unlock(&cifs_tcp_ses_lock);
+
+	cifs_close_all_deferred_files(tcon);
+	/* cancel_brl_requests(tcon); */ /* BB mark all brl mids as exiting */
+	/* cancel_notify_requests(tcon); */
+	if (tcon->ses && tcon->ses->server) {
+		cifs_dbg(FYI, "wake up tasks now - umount begin not complete\n");
+		wake_up_all(&tcon->ses->server->request_q);
+		wake_up_all(&tcon->ses->server->response_q);
+		msleep(1); /* yield */
+		/* we have to kick the requests once more */
+		wake_up_all(&tcon->ses->server->response_q);
+		msleep(1);
+	}
+
+	return;
+}
+
+static int cifs_freeze(struct super_block *sb)
+{
+	struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
+	struct cifs_tcon *tcon;
+
+	if (cifs_sb == NULL)
+		return 0;
+
+	tcon = cifs_sb_master_tcon(cifs_sb);
+
+	cifs_close_all_deferred_files(tcon);
+	return 0;
+}
+
+#ifdef CONFIG_CIFS_STATS2
+static int cifs_show_stats(struct seq_file *s, struct dentry *root)
+{
+	/* BB FIXME */
+	return 0;
+}
+#endif
+
+static int cifs_write_inode(struct inode *inode, struct writeback_control *wbc)
+{
+	fscache_unpin_writeback(wbc, cifs_inode_cookie(inode));
+	return 0;
+}
+
+static int cifs_drop_inode(struct inode *inode)
+{
+	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
+
+	/* no serverino => unconditional eviction */
+	return !(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) ||
+		generic_drop_inode(inode);
+}
+
+static const struct super_operations cifs_super_ops = {
+	.statfs = cifs_statfs,
+	.alloc_inode = cifs_alloc_inode,
+	.write_inode	= cifs_write_inode,
+	.free_inode = cifs_free_inode,
+	.drop_inode	= cifs_drop_inode,
+	.evict_inode	= cifs_evict_inode,
+/*	.show_path	= cifs_show_path, */ /* Would we ever need show path? */
+	.show_devname   = cifs_show_devname,
+/*	.delete_inode	= cifs_delete_inode,  */  /* Do not need above
+	function unless later we add lazy close of inodes or unless the
+	kernel forgets to call us with the same number of releases (closes)
+	as opens */
+	.show_options = cifs_show_options,
+	.umount_begin   = cifs_umount_begin,
+	.freeze_fs      = cifs_freeze,
+#ifdef CONFIG_CIFS_STATS2
+	.show_stats = cifs_show_stats,
+#endif
+};
+
+/*
+ * Get root dentry from superblock according to prefix path mount option.
+ * Return dentry with refcount + 1 on success and NULL otherwise.
+ */
+static struct dentry *
+cifs_get_root(struct smb3_fs_context *ctx, struct super_block *sb)
+{
+	struct dentry *dentry;
+	struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
+	char *full_path = NULL;
+	char *s, *p;
+	char sep;
+
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH)
+		return dget(sb->s_root);
+
+	full_path = cifs_build_path_to_root(ctx, cifs_sb,
+				cifs_sb_master_tcon(cifs_sb), 0);
+	if (full_path == NULL)
+		return ERR_PTR(-ENOMEM);
+
+	cifs_dbg(FYI, "Get root dentry for %s\n", full_path);
+
+	sep = CIFS_DIR_SEP(cifs_sb);
+	dentry = dget(sb->s_root);
+	s = full_path;
+
+	do {
+		struct inode *dir = d_inode(dentry);
+		struct dentry *child;
+
+		if (!S_ISDIR(dir->i_mode)) {
+			dput(dentry);
+			dentry = ERR_PTR(-ENOTDIR);
+			break;
+		}
+
+		/* skip separators */
+		while (*s == sep)
+			s++;
+		if (!*s)
+			break;
+		p = s++;
+		/* next separator */
+		while (*s && *s != sep)
+			s++;
+
+		child = lookup_positive_unlocked(p, dentry, s - p);
+		dput(dentry);
+		dentry = child;
+	} while (!IS_ERR(dentry));
+	kfree(full_path);
+	return dentry;
+}
+
+static int cifs_set_super(struct super_block *sb, void *data)
+{
+	struct cifs_mnt_data *mnt_data = data;
+	sb->s_fs_info = mnt_data->cifs_sb;
+	return set_anon_super(sb, NULL);
+}
+
+struct dentry *
+cifs_smb3_do_mount(struct file_system_type *fs_type,
+	      int flags, struct smb3_fs_context *old_ctx)
+{
+	int rc;
+	struct super_block *sb = NULL;
+	struct cifs_sb_info *cifs_sb = NULL;
+	struct cifs_mnt_data mnt_data;
+	struct dentry *root;
+
+	if (cifsFYI) {
+		cifs_dbg(FYI, "%s: devname=%s flags=0x%x\n", __func__,
+			 old_ctx->source, flags);
+	} else {
+		cifs_info("Attempting to mount %s\n", old_ctx->source);
+	}
+
+	cifs_sb = kzalloc(sizeof(struct cifs_sb_info), GFP_KERNEL);
+	if (cifs_sb == NULL) {
+		root = ERR_PTR(-ENOMEM);
+		goto out;
+	}
+
+	cifs_sb->ctx = kzalloc(sizeof(struct smb3_fs_context), GFP_KERNEL);
+	if (!cifs_sb->ctx) {
+		root = ERR_PTR(-ENOMEM);
+		goto out;
+	}
+	rc = smb3_fs_context_dup(cifs_sb->ctx, old_ctx);
+	if (rc) {
+		root = ERR_PTR(rc);
+		goto out;
+	}
+
+	rc = cifs_setup_cifs_sb(cifs_sb);
+	if (rc) {
+		root = ERR_PTR(rc);
+		goto out;
+	}
+
+	rc = cifs_mount(cifs_sb, cifs_sb->ctx);
+	if (rc) {
+		if (!(flags & SB_SILENT))
+			cifs_dbg(VFS, "cifs_mount failed w/return code = %d\n",
+				 rc);
+		root = ERR_PTR(rc);
+		goto out;
+	}
+
+	mnt_data.ctx = cifs_sb->ctx;
+	mnt_data.cifs_sb = cifs_sb;
+	mnt_data.flags = flags;
+
+	/* BB should we make this contingent on mount parm? */
+	flags |= SB_NODIRATIME | SB_NOATIME;
+
+	sb = sget(fs_type, cifs_match_super, cifs_set_super, flags, &mnt_data);
+	if (IS_ERR(sb)) {
+		root = ERR_CAST(sb);
+		cifs_umount(cifs_sb);
+		cifs_sb = NULL;
+		goto out;
+	}
+
+	if (sb->s_root) {
+		cifs_dbg(FYI, "Use existing superblock\n");
+		cifs_umount(cifs_sb);
+		cifs_sb = NULL;
+	} else {
+		rc = cifs_read_super(sb);
+		if (rc) {
+			root = ERR_PTR(rc);
+			goto out_super;
+		}
+
+		sb->s_flags |= SB_ACTIVE;
+	}
+
+	root = cifs_get_root(cifs_sb ? cifs_sb->ctx : old_ctx, sb);
+	if (IS_ERR(root))
+		goto out_super;
+
+	if (cifs_sb)
+		cifs_sb->root = dget(root);
+
+	cifs_dbg(FYI, "dentry root is: %p\n", root);
+	return root;
+
+out_super:
+	deactivate_locked_super(sb);
+	return root;
+out:
+	if (cifs_sb) {
+		if (!sb || IS_ERR(sb)) {  /* otherwise kill_sb will handle */
+			kfree(cifs_sb->prepath);
+			smb3_cleanup_fs_context(cifs_sb->ctx);
+			kfree(cifs_sb);
+		}
+	}
+	return root;
+}
+
+
+static ssize_t
+cifs_loose_read_iter(struct kiocb *iocb, struct iov_iter *iter)
+{
+	ssize_t rc;
+	struct inode *inode = file_inode(iocb->ki_filp);
+
+	if (iocb->ki_flags & IOCB_DIRECT)
+		return cifs_user_readv(iocb, iter);
+
+	rc = cifs_revalidate_mapping(inode);
+	if (rc)
+		return rc;
+
+	return generic_file_read_iter(iocb, iter);
+}
+
+static ssize_t cifs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
+{
+	struct inode *inode = file_inode(iocb->ki_filp);
+	struct cifsInodeInfo *cinode = CIFS_I(inode);
+	ssize_t written;
+	int rc;
+
+	if (iocb->ki_filp->f_flags & O_DIRECT) {
+		written = cifs_user_writev(iocb, from);
+		if (written > 0 && CIFS_CACHE_READ(cinode)) {
+			cifs_zap_mapping(inode);
+			cifs_dbg(FYI,
+				 "Set no oplock for inode=%p after a write operation\n",
+				 inode);
+			cinode->oplock = 0;
+		}
+		return written;
+	}
+
+	written = cifs_get_writer(cinode);
+	if (written)
+		return written;
+
+	written = generic_file_write_iter(iocb, from);
+
+	if (CIFS_CACHE_WRITE(CIFS_I(inode)))
+		goto out;
+
+	rc = filemap_fdatawrite(inode->i_mapping);
+	if (rc)
+		cifs_dbg(FYI, "cifs_file_write_iter: %d rc on %p inode\n",
+			 rc, inode);
+
+out:
+	cifs_put_writer(cinode);
+	return written;
+}
+
+static loff_t cifs_llseek(struct file *file, loff_t offset, int whence)
+{
+	struct cifsFileInfo *cfile = file->private_data;
+	struct cifs_tcon *tcon;
+
+	/*
+	 * whence == SEEK_END || SEEK_DATA || SEEK_HOLE => we must revalidate
+	 * the cached file length
+	 */
+	if (whence != SEEK_SET && whence != SEEK_CUR) {
+		int rc;
+		struct inode *inode = file_inode(file);
+
+		/*
+		 * We need to be sure that all dirty pages are written and the
+		 * server has the newest file length.
+		 */
+		if (!CIFS_CACHE_READ(CIFS_I(inode)) && inode->i_mapping &&
+		    inode->i_mapping->nrpages != 0) {
+			rc = filemap_fdatawait(inode->i_mapping);
+			if (rc) {
+				mapping_set_error(inode->i_mapping, rc);
+				return rc;
+			}
+		}
+		/*
+		 * Some applications poll for the file length in this strange
+		 * way so we must seek to end on non-oplocked files by
+		 * setting the revalidate time to zero.
+		 */
+		CIFS_I(inode)->time = 0;
+
+		rc = cifs_revalidate_file_attr(file);
+		if (rc < 0)
+			return (loff_t)rc;
+	}
+	if (cfile && cfile->tlink) {
+		tcon = tlink_tcon(cfile->tlink);
+		if (tcon->ses->server->ops->llseek)
+			return tcon->ses->server->ops->llseek(file, tcon,
+							      offset, whence);
+	}
+	return generic_file_llseek(file, offset, whence);
+}
+
+static int
+cifs_setlease(struct file *file, long arg, struct file_lock **lease, void **priv)
+{
+	/*
+	 * Note that this is called by vfs setlease with i_lock held to
+	 * protect *lease from going away.
+	 */
+	struct inode *inode = file_inode(file);
+	struct cifsFileInfo *cfile = file->private_data;
+
+	if (!(S_ISREG(inode->i_mode)))
+		return -EINVAL;
+
+	/* Check if file is oplocked if this is request for new lease */
+	if (arg == F_UNLCK ||
+	    ((arg == F_RDLCK) && CIFS_CACHE_READ(CIFS_I(inode))) ||
+	    ((arg == F_WRLCK) && CIFS_CACHE_WRITE(CIFS_I(inode))))
+		return generic_setlease(file, arg, lease, priv);
+	else if (tlink_tcon(cfile->tlink)->local_lease &&
+		 !CIFS_CACHE_READ(CIFS_I(inode)))
+		/*
+		 * If the server claims to support oplock on this file, then we
+		 * still need to check oplock even if the local_lease mount
+		 * option is set, but there are servers which do not support
+		 * oplock for which this mount option may be useful if the user
+		 * knows that the file won't be changed on the server by anyone
+		 * else.
+		 */
+		return generic_setlease(file, arg, lease, priv);
+	else
+		return -EAGAIN;
+}
+
+struct file_system_type cifs_fs_type = {
+	.owner = THIS_MODULE,
+	.name = "cifs",
+	.init_fs_context = smb3_init_fs_context,
+	.parameters = smb3_fs_parameters,
+	.kill_sb = cifs_kill_sb,
+	.fs_flags = FS_RENAME_DOES_D_MOVE,
+};
+MODULE_ALIAS_FS("cifs");
+
+struct file_system_type smb3_fs_type = {
+	.owner = THIS_MODULE,
+	.name = "smb3",
+	.init_fs_context = smb3_init_fs_context,
+	.parameters = smb3_fs_parameters,
+	.kill_sb = cifs_kill_sb,
+	.fs_flags = FS_RENAME_DOES_D_MOVE,
+};
+MODULE_ALIAS_FS("smb3");
+MODULE_ALIAS("smb3");
+
+const struct inode_operations cifs_dir_inode_ops = {
+	.create = cifs_create,
+	.atomic_open = cifs_atomic_open,
+	.lookup = cifs_lookup,
+	.getattr = cifs_getattr,
+	.unlink = cifs_unlink,
+	.link = cifs_hardlink,
+	.mkdir = cifs_mkdir,
+	.rmdir = cifs_rmdir,
+	.rename = cifs_rename2,
+	.permission = cifs_permission,
+	.setattr = cifs_setattr,
+	.symlink = cifs_symlink,
+	.mknod   = cifs_mknod,
+	.listxattr = cifs_listxattr,
+	.get_acl = cifs_get_acl,
+	.set_acl = cifs_set_acl,
+};
+
+const struct inode_operations cifs_file_inode_ops = {
+	.setattr = cifs_setattr,
+	.getattr = cifs_getattr,
+	.permission = cifs_permission,
+	.listxattr = cifs_listxattr,
+	.fiemap = cifs_fiemap,
+	.get_acl = cifs_get_acl,
+	.set_acl = cifs_set_acl,
+};
+
+const char *cifs_get_link(struct dentry *dentry, struct inode *inode,
+			    struct delayed_call *done)
+{
+	char *target_path;
+
+	target_path = kmalloc(PATH_MAX, GFP_KERNEL);
+	if (!target_path)
+		return ERR_PTR(-ENOMEM);
+
+	spin_lock(&inode->i_lock);
+	if (likely(CIFS_I(inode)->symlink_target)) {
+		strscpy(target_path, CIFS_I(inode)->symlink_target, PATH_MAX);
+	} else {
+		kfree(target_path);
+		target_path = ERR_PTR(-EOPNOTSUPP);
+	}
+	spin_unlock(&inode->i_lock);
+
+	if (!IS_ERR(target_path))
+		set_delayed_call(done, kfree_link, target_path);
+
+	return target_path;
+}
+
+const struct inode_operations cifs_symlink_inode_ops = {
+	.get_link = cifs_get_link,
+	.permission = cifs_permission,
+	.listxattr = cifs_listxattr,
+};
+
+static loff_t cifs_remap_file_range(struct file *src_file, loff_t off,
+		struct file *dst_file, loff_t destoff, loff_t len,
+		unsigned int remap_flags)
+{
+	struct inode *src_inode = file_inode(src_file);
+	struct inode *target_inode = file_inode(dst_file);
+	struct cifsFileInfo *smb_file_src = src_file->private_data;
+	struct cifsFileInfo *smb_file_target;
+	struct cifs_tcon *target_tcon;
+	unsigned int xid;
+	int rc;
+
+	if (remap_flags & ~(REMAP_FILE_DEDUP | REMAP_FILE_ADVISORY))
+		return -EINVAL;
+
+	cifs_dbg(FYI, "clone range\n");
+
+	xid = get_xid();
+
+	if (!src_file->private_data || !dst_file->private_data) {
+		rc = -EBADF;
+		cifs_dbg(VFS, "missing cifsFileInfo on copy range src file\n");
+		goto out;
+	}
+
+	smb_file_target = dst_file->private_data;
+	target_tcon = tlink_tcon(smb_file_target->tlink);
+
+	/*
+	 * Note: cifs case is easier than btrfs since server responsible for
+	 * checks for proper open modes and file type and if it wants
+	 * server could even support copy of range where source = target
+	 */
+	lock_two_nondirectories(target_inode, src_inode);
+
+	if (len == 0)
+		len = src_inode->i_size - off;
+
+	cifs_dbg(FYI, "about to flush pages\n");
+	/* should we flush first and last page first */
+	truncate_inode_pages_range(&target_inode->i_data, destoff,
+				   PAGE_ALIGN(destoff + len)-1);
+
+	if (target_tcon->ses->server->ops->duplicate_extents)
+		rc = target_tcon->ses->server->ops->duplicate_extents(xid,
+			smb_file_src, smb_file_target, off, len, destoff);
+	else
+		rc = -EOPNOTSUPP;
+
+	/* force revalidate of size and timestamps of target file now
+	   that target is updated on the server */
+	CIFS_I(target_inode)->time = 0;
+	/* although unlocking in the reverse order from locking is not
+	   strictly necessary here it is a little cleaner to be consistent */
+	unlock_two_nondirectories(src_inode, target_inode);
+out:
+	free_xid(xid);
+	return rc < 0 ? rc : len;
+}
+
+ssize_t cifs_file_copychunk_range(unsigned int xid,
+				struct file *src_file, loff_t off,
+				struct file *dst_file, loff_t destoff,
+				size_t len, unsigned int flags)
+{
+	struct inode *src_inode = file_inode(src_file);
+	struct inode *target_inode = file_inode(dst_file);
+	struct cifsFileInfo *smb_file_src;
+	struct cifsFileInfo *smb_file_target;
+	struct cifs_tcon *src_tcon;
+	struct cifs_tcon *target_tcon;
+	ssize_t rc;
+
+	cifs_dbg(FYI, "copychunk range\n");
+
+	if (!src_file->private_data || !dst_file->private_data) {
+		rc = -EBADF;
+		cifs_dbg(VFS, "missing cifsFileInfo on copy range src file\n");
+		goto out;
+	}
+
+	rc = -EXDEV;
+	smb_file_target = dst_file->private_data;
+	smb_file_src = src_file->private_data;
+	src_tcon = tlink_tcon(smb_file_src->tlink);
+	target_tcon = tlink_tcon(smb_file_target->tlink);
+
+	if (src_tcon->ses != target_tcon->ses) {
+		cifs_dbg(VFS, "source and target of copy not on same server\n");
+		goto out;
+	}
+
+	rc = -EOPNOTSUPP;
+	if (!target_tcon->ses->server->ops->copychunk_range)
+		goto out;
+
+	/*
+	 * Note: cifs case is easier than btrfs since server responsible for
+	 * checks for proper open modes and file type and if it wants
+	 * server could even support copy of range where source = target
+	 */
+	lock_two_nondirectories(target_inode, src_inode);
+
+	cifs_dbg(FYI, "about to flush pages\n");
+
+	rc = filemap_write_and_wait_range(src_inode->i_mapping, off,
+					  off + len - 1);
+	if (rc)
+		goto unlock;
+
+	/* should we flush first and last page first */
+	truncate_inode_pages(&target_inode->i_data, 0);
+
+	rc = file_modified(dst_file);
+	if (!rc)
+		rc = target_tcon->ses->server->ops->copychunk_range(xid,
+			smb_file_src, smb_file_target, off, len, destoff);
+
+	file_accessed(src_file);
+
+	/* force revalidate of size and timestamps of target file now
+	 * that target is updated on the server
+	 */
+	CIFS_I(target_inode)->time = 0;
+
+unlock:
+	/* although unlocking in the reverse order from locking is not
+	 * strictly necessary here it is a little cleaner to be consistent
+	 */
+	unlock_two_nondirectories(src_inode, target_inode);
+
+out:
+	return rc;
+}
+
+/*
+ * Directory operations under CIFS/SMB2/SMB3 are synchronous, so fsync()
+ * is a dummy operation.
+ */
+static int cifs_dir_fsync(struct file *file, loff_t start, loff_t end, int datasync)
+{
+	cifs_dbg(FYI, "Sync directory - name: %pD datasync: 0x%x\n",
+		 file, datasync);
+
+	return 0;
+}
+
+static ssize_t cifs_copy_file_range(struct file *src_file, loff_t off,
+				struct file *dst_file, loff_t destoff,
+				size_t len, unsigned int flags)
+{
+	unsigned int xid = get_xid();
+	ssize_t rc;
+	struct cifsFileInfo *cfile = dst_file->private_data;
+
+	if (cfile->swapfile) {
+		rc = -EOPNOTSUPP;
+		free_xid(xid);
+		return rc;
+	}
+
+	rc = cifs_file_copychunk_range(xid, src_file, off, dst_file, destoff,
+					len, flags);
+	free_xid(xid);
+
+	if (rc == -EOPNOTSUPP || rc == -EXDEV)
+		rc = generic_copy_file_range(src_file, off, dst_file,
+					     destoff, len, flags);
+	return rc;
+}
+
+const struct file_operations cifs_file_ops = {
+	.read_iter = cifs_loose_read_iter,
+	.write_iter = cifs_file_write_iter,
+	.open = cifs_open,
+	.release = cifs_close,
+	.lock = cifs_lock,
+	.flock = cifs_flock,
+	.fsync = cifs_fsync,
+	.flush = cifs_flush,
+	.mmap  = cifs_file_mmap,
+	.splice_read = cifs_splice_read,
+	.splice_write = iter_file_splice_write,
+	.llseek = cifs_llseek,
+	.unlocked_ioctl	= cifs_ioctl,
+	.copy_file_range = cifs_copy_file_range,
+	.remap_file_range = cifs_remap_file_range,
+	.setlease = cifs_setlease,
+	.fallocate = cifs_fallocate,
+};
+
+const struct file_operations cifs_file_strict_ops = {
+	.read_iter = cifs_strict_readv,
+	.write_iter = cifs_strict_writev,
+	.open = cifs_open,
+	.release = cifs_close,
+	.lock = cifs_lock,
+	.flock = cifs_flock,
+	.fsync = cifs_strict_fsync,
+	.flush = cifs_flush,
+	.mmap = cifs_file_strict_mmap,
+	.splice_read = cifs_splice_read,
+	.splice_write = iter_file_splice_write,
+	.llseek = cifs_llseek,
+	.unlocked_ioctl	= cifs_ioctl,
+	.copy_file_range = cifs_copy_file_range,
+	.remap_file_range = cifs_remap_file_range,
+	.setlease = cifs_setlease,
+	.fallocate = cifs_fallocate,
+};
+
+const struct file_operations cifs_file_direct_ops = {
+	.read_iter = cifs_direct_readv,
+	.write_iter = cifs_direct_writev,
+	.open = cifs_open,
+	.release = cifs_close,
+	.lock = cifs_lock,
+	.flock = cifs_flock,
+	.fsync = cifs_fsync,
+	.flush = cifs_flush,
+	.mmap = cifs_file_mmap,
+	.splice_read = direct_splice_read,
+	.splice_write = iter_file_splice_write,
+	.unlocked_ioctl  = cifs_ioctl,
+	.copy_file_range = cifs_copy_file_range,
+	.remap_file_range = cifs_remap_file_range,
+	.llseek = cifs_llseek,
+	.setlease = cifs_setlease,
+	.fallocate = cifs_fallocate,
+};
+
+const struct file_operations cifs_file_nobrl_ops = {
+	.read_iter = cifs_loose_read_iter,
+	.write_iter = cifs_file_write_iter,
+	.open = cifs_open,
+	.release = cifs_close,
+	.fsync = cifs_fsync,
+	.flush = cifs_flush,
+	.mmap  = cifs_file_mmap,
+	.splice_read = cifs_splice_read,
+	.splice_write = iter_file_splice_write,
+	.llseek = cifs_llseek,
+	.unlocked_ioctl	= cifs_ioctl,
+	.copy_file_range = cifs_copy_file_range,
+	.remap_file_range = cifs_remap_file_range,
+	.setlease = cifs_setlease,
+	.fallocate = cifs_fallocate,
+};
+
+const struct file_operations cifs_file_strict_nobrl_ops = {
+	.read_iter = cifs_strict_readv,
+	.write_iter = cifs_strict_writev,
+	.open = cifs_open,
+	.release = cifs_close,
+	.fsync = cifs_strict_fsync,
+	.flush = cifs_flush,
+	.mmap = cifs_file_strict_mmap,
+	.splice_read = cifs_splice_read,
+	.splice_write = iter_file_splice_write,
+	.llseek = cifs_llseek,
+	.unlocked_ioctl	= cifs_ioctl,
+	.copy_file_range = cifs_copy_file_range,
+	.remap_file_range = cifs_remap_file_range,
+	.setlease = cifs_setlease,
+	.fallocate = cifs_fallocate,
+};
+
+const struct file_operations cifs_file_direct_nobrl_ops = {
+	.read_iter = cifs_direct_readv,
+	.write_iter = cifs_direct_writev,
+	.open = cifs_open,
+	.release = cifs_close,
+	.fsync = cifs_fsync,
+	.flush = cifs_flush,
+	.mmap = cifs_file_mmap,
+	.splice_read = direct_splice_read,
+	.splice_write = iter_file_splice_write,
+	.unlocked_ioctl  = cifs_ioctl,
+	.copy_file_range = cifs_copy_file_range,
+	.remap_file_range = cifs_remap_file_range,
+	.llseek = cifs_llseek,
+	.setlease = cifs_setlease,
+	.fallocate = cifs_fallocate,
+};
+
+const struct file_operations cifs_dir_ops = {
+	.iterate_shared = cifs_readdir,
+	.release = cifs_closedir,
+	.read    = generic_read_dir,
+	.unlocked_ioctl  = cifs_ioctl,
+	.copy_file_range = cifs_copy_file_range,
+	.remap_file_range = cifs_remap_file_range,
+	.llseek = generic_file_llseek,
+	.fsync = cifs_dir_fsync,
+};
+
+static void
+cifs_init_once(void *inode)
+{
+	struct cifsInodeInfo *cifsi = inode;
+
+	inode_init_once(&cifsi->netfs.inode);
+	init_rwsem(&cifsi->lock_sem);
+}
+
+static int __init
+cifs_init_inodecache(void)
+{
+	cifs_inode_cachep = kmem_cache_create("cifs_inode_cache",
+					      sizeof(struct cifsInodeInfo),
+					      0, (SLAB_RECLAIM_ACCOUNT|
+						SLAB_MEM_SPREAD|SLAB_ACCOUNT),
+					      cifs_init_once);
+	if (cifs_inode_cachep == NULL)
+		return -ENOMEM;
+
+	return 0;
+}
+
+static void
+cifs_destroy_inodecache(void)
+{
+	/*
+	 * Make sure all delayed rcu free inodes are flushed before we
+	 * destroy cache.
+	 */
+	rcu_barrier();
+	kmem_cache_destroy(cifs_inode_cachep);
+}
+
+static int
+cifs_init_request_bufs(void)
+{
+	/*
+	 * SMB2 maximum header size is bigger than CIFS one - no problems to
+	 * allocate some more bytes for CIFS.
+	 */
+	size_t max_hdr_size = MAX_SMB2_HDR_SIZE;
+
+	if (CIFSMaxBufSize < 8192) {
+	/* Buffer size can not be smaller than 2 * PATH_MAX since maximum
+	Unicode path name has to fit in any SMB/CIFS path based frames */
+		CIFSMaxBufSize = 8192;
+	} else if (CIFSMaxBufSize > 1024*127) {
+		CIFSMaxBufSize = 1024 * 127;
+	} else {
+		CIFSMaxBufSize &= 0x1FE00; /* Round size to even 512 byte mult*/
+	}
+/*
+	cifs_dbg(VFS, "CIFSMaxBufSize %d 0x%x\n",
+		 CIFSMaxBufSize, CIFSMaxBufSize);
+*/
+	cifs_req_cachep = kmem_cache_create_usercopy("cifs_request",
+					    CIFSMaxBufSize + max_hdr_size, 0,
+					    SLAB_HWCACHE_ALIGN, 0,
+					    CIFSMaxBufSize + max_hdr_size,
+					    NULL);
+	if (cifs_req_cachep == NULL)
+		return -ENOMEM;
+
+	if (cifs_min_rcv < 1)
+		cifs_min_rcv = 1;
+	else if (cifs_min_rcv > 64) {
+		cifs_min_rcv = 64;
+		cifs_dbg(VFS, "cifs_min_rcv set to maximum (64)\n");
+	}
+
+	cifs_req_poolp = mempool_create_slab_pool(cifs_min_rcv,
+						  cifs_req_cachep);
+
+	if (cifs_req_poolp == NULL) {
+		kmem_cache_destroy(cifs_req_cachep);
+		return -ENOMEM;
+	}
+	/* MAX_CIFS_SMALL_BUFFER_SIZE bytes is enough for most SMB responses and
+	almost all handle based requests (but not write response, nor is it
+	sufficient for path based requests).  A smaller size would have
+	been more efficient (compacting multiple slab items on one 4k page)
+	for the case in which debug was on, but this larger size allows
+	more SMBs to use small buffer alloc and is still much more
+	efficient to alloc 1 per page off the slab compared to 17K (5page)
+	alloc of large cifs buffers even when page debugging is on */
+	cifs_sm_req_cachep = kmem_cache_create_usercopy("cifs_small_rq",
+			MAX_CIFS_SMALL_BUFFER_SIZE, 0, SLAB_HWCACHE_ALIGN,
+			0, MAX_CIFS_SMALL_BUFFER_SIZE, NULL);
+	if (cifs_sm_req_cachep == NULL) {
+		mempool_destroy(cifs_req_poolp);
+		kmem_cache_destroy(cifs_req_cachep);
+		return -ENOMEM;
+	}
+
+	if (cifs_min_small < 2)
+		cifs_min_small = 2;
+	else if (cifs_min_small > 256) {
+		cifs_min_small = 256;
+		cifs_dbg(FYI, "cifs_min_small set to maximum (256)\n");
+	}
+
+	cifs_sm_req_poolp = mempool_create_slab_pool(cifs_min_small,
+						     cifs_sm_req_cachep);
+
+	if (cifs_sm_req_poolp == NULL) {
+		mempool_destroy(cifs_req_poolp);
+		kmem_cache_destroy(cifs_req_cachep);
+		kmem_cache_destroy(cifs_sm_req_cachep);
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static void
+cifs_destroy_request_bufs(void)
+{
+	mempool_destroy(cifs_req_poolp);
+	kmem_cache_destroy(cifs_req_cachep);
+	mempool_destroy(cifs_sm_req_poolp);
+	kmem_cache_destroy(cifs_sm_req_cachep);
+}
+
+static int init_mids(void)
+{
+	cifs_mid_cachep = kmem_cache_create("cifs_mpx_ids",
+					    sizeof(struct mid_q_entry), 0,
+					    SLAB_HWCACHE_ALIGN, NULL);
+	if (cifs_mid_cachep == NULL)
+		return -ENOMEM;
+
+	/* 3 is a reasonable minimum number of simultaneous operations */
+	cifs_mid_poolp = mempool_create_slab_pool(3, cifs_mid_cachep);
+	if (cifs_mid_poolp == NULL) {
+		kmem_cache_destroy(cifs_mid_cachep);
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static void destroy_mids(void)
+{
+	mempool_destroy(cifs_mid_poolp);
+	kmem_cache_destroy(cifs_mid_cachep);
+}
+
+static int __init
+init_cifs(void)
+{
+	int rc = 0;
+	cifs_proc_init();
+	INIT_LIST_HEAD(&cifs_tcp_ses_list);
+/*
+ *  Initialize Global counters
+ */
+	atomic_set(&sesInfoAllocCount, 0);
+	atomic_set(&tconInfoAllocCount, 0);
+	atomic_set(&tcpSesNextId, 0);
+	atomic_set(&tcpSesAllocCount, 0);
+	atomic_set(&tcpSesReconnectCount, 0);
+	atomic_set(&tconInfoReconnectCount, 0);
+
+	atomic_set(&buf_alloc_count, 0);
+	atomic_set(&small_buf_alloc_count, 0);
+#ifdef CONFIG_CIFS_STATS2
+	atomic_set(&total_buf_alloc_count, 0);
+	atomic_set(&total_small_buf_alloc_count, 0);
+	if (slow_rsp_threshold < 1)
+		cifs_dbg(FYI, "slow_response_threshold msgs disabled\n");
+	else if (slow_rsp_threshold > 32767)
+		cifs_dbg(VFS,
+		       "slow response threshold set higher than recommended (0 to 32767)\n");
+#endif /* CONFIG_CIFS_STATS2 */
+
+	atomic_set(&mid_count, 0);
+	GlobalCurrentXid = 0;
+	GlobalTotalActiveXid = 0;
+	GlobalMaxActiveXid = 0;
+	spin_lock_init(&cifs_tcp_ses_lock);
+	spin_lock_init(&GlobalMid_Lock);
+
+	cifs_lock_secret = get_random_u32();
+
+	if (cifs_max_pending < 2) {
+		cifs_max_pending = 2;
+		cifs_dbg(FYI, "cifs_max_pending set to min of 2\n");
+	} else if (cifs_max_pending > CIFS_MAX_REQ) {
+		cifs_max_pending = CIFS_MAX_REQ;
+		cifs_dbg(FYI, "cifs_max_pending set to max of %u\n",
+			 CIFS_MAX_REQ);
+	}
+
+	cifsiod_wq = alloc_workqueue("cifsiod", WQ_FREEZABLE|WQ_MEM_RECLAIM, 0);
+	if (!cifsiod_wq) {
+		rc = -ENOMEM;
+		goto out_clean_proc;
+	}
+
+	/*
+	 * Consider in future setting limit!=0 maybe to min(num_of_cores - 1, 3)
+	 * so that we don't launch too many worker threads but
+	 * Documentation/core-api/workqueue.rst recommends setting it to 0
+	 */
+
+	/* WQ_UNBOUND allows decrypt tasks to run on any CPU */
+	decrypt_wq = alloc_workqueue("smb3decryptd",
+				     WQ_UNBOUND|WQ_FREEZABLE|WQ_MEM_RECLAIM, 0);
+	if (!decrypt_wq) {
+		rc = -ENOMEM;
+		goto out_destroy_cifsiod_wq;
+	}
+
+	fileinfo_put_wq = alloc_workqueue("cifsfileinfoput",
+				     WQ_UNBOUND|WQ_FREEZABLE|WQ_MEM_RECLAIM, 0);
+	if (!fileinfo_put_wq) {
+		rc = -ENOMEM;
+		goto out_destroy_decrypt_wq;
+	}
+
+	cifsoplockd_wq = alloc_workqueue("cifsoplockd",
+					 WQ_FREEZABLE|WQ_MEM_RECLAIM, 0);
+	if (!cifsoplockd_wq) {
+		rc = -ENOMEM;
+		goto out_destroy_fileinfo_put_wq;
+	}
+
+	deferredclose_wq = alloc_workqueue("deferredclose",
+					   WQ_FREEZABLE|WQ_MEM_RECLAIM, 0);
+	if (!deferredclose_wq) {
+		rc = -ENOMEM;
+		goto out_destroy_cifsoplockd_wq;
+	}
+
+	rc = cifs_init_inodecache();
+	if (rc)
+		goto out_destroy_deferredclose_wq;
+
+	rc = init_mids();
+	if (rc)
+		goto out_destroy_inodecache;
+
+	rc = cifs_init_request_bufs();
+	if (rc)
+		goto out_destroy_mids;
+
+#ifdef CONFIG_CIFS_DFS_UPCALL
+	rc = dfs_cache_init();
+	if (rc)
+		goto out_destroy_request_bufs;
+#endif /* CONFIG_CIFS_DFS_UPCALL */
+#ifdef CONFIG_CIFS_UPCALL
+	rc = init_cifs_spnego();
+	if (rc)
+		goto out_destroy_dfs_cache;
+#endif /* CONFIG_CIFS_UPCALL */
+#ifdef CONFIG_CIFS_SWN_UPCALL
+	rc = cifs_genl_init();
+	if (rc)
+		goto out_register_key_type;
+#endif /* CONFIG_CIFS_SWN_UPCALL */
+
+	rc = init_cifs_idmap();
+	if (rc)
+		goto out_cifs_swn_init;
+
+	rc = register_filesystem(&cifs_fs_type);
+	if (rc)
+		goto out_init_cifs_idmap;
+
+	rc = register_filesystem(&smb3_fs_type);
+	if (rc) {
+		unregister_filesystem(&cifs_fs_type);
+		goto out_init_cifs_idmap;
+	}
+
+	return 0;
+
+out_init_cifs_idmap:
+	exit_cifs_idmap();
+out_cifs_swn_init:
+#ifdef CONFIG_CIFS_SWN_UPCALL
+	cifs_genl_exit();
+out_register_key_type:
+#endif
+#ifdef CONFIG_CIFS_UPCALL
+	exit_cifs_spnego();
+out_destroy_dfs_cache:
+#endif
+#ifdef CONFIG_CIFS_DFS_UPCALL
+	dfs_cache_destroy();
+out_destroy_request_bufs:
+#endif
+	cifs_destroy_request_bufs();
+out_destroy_mids:
+	destroy_mids();
+out_destroy_inodecache:
+	cifs_destroy_inodecache();
+out_destroy_deferredclose_wq:
+	destroy_workqueue(deferredclose_wq);
+out_destroy_cifsoplockd_wq:
+	destroy_workqueue(cifsoplockd_wq);
+out_destroy_fileinfo_put_wq:
+	destroy_workqueue(fileinfo_put_wq);
+out_destroy_decrypt_wq:
+	destroy_workqueue(decrypt_wq);
+out_destroy_cifsiod_wq:
+	destroy_workqueue(cifsiod_wq);
+out_clean_proc:
+	cifs_proc_clean();
+	return rc;
+}
+
+static void __exit
+exit_cifs(void)
+{
+	cifs_dbg(NOISY, "exit_smb3\n");
+	unregister_filesystem(&cifs_fs_type);
+	unregister_filesystem(&smb3_fs_type);
+	cifs_dfs_release_automount_timer();
+	exit_cifs_idmap();
+#ifdef CONFIG_CIFS_SWN_UPCALL
+	cifs_genl_exit();
+#endif
+#ifdef CONFIG_CIFS_UPCALL
+	exit_cifs_spnego();
+#endif
+#ifdef CONFIG_CIFS_DFS_UPCALL
+	dfs_cache_destroy();
+#endif
+	cifs_destroy_request_bufs();
+	destroy_mids();
+	cifs_destroy_inodecache();
+	destroy_workqueue(deferredclose_wq);
+	destroy_workqueue(cifsoplockd_wq);
+	destroy_workqueue(decrypt_wq);
+	destroy_workqueue(fileinfo_put_wq);
+	destroy_workqueue(cifsiod_wq);
+	cifs_proc_clean();
+}
+
+MODULE_AUTHOR("Steve French");
+MODULE_LICENSE("GPL");	/* combination of LGPL + GPL source behaves as GPL */
+MODULE_DESCRIPTION
+	("VFS to access SMB3 servers e.g. Samba, Macs, Azure and Windows (and "
+	"also older servers complying with the SNIA CIFS Specification)");
+MODULE_VERSION(CIFS_VERSION);
+MODULE_SOFTDEP("ecb");
+MODULE_SOFTDEP("hmac");
+MODULE_SOFTDEP("md5");
+MODULE_SOFTDEP("nls");
+MODULE_SOFTDEP("aes");
+MODULE_SOFTDEP("cmac");
+MODULE_SOFTDEP("sha256");
+MODULE_SOFTDEP("sha512");
+MODULE_SOFTDEP("aead2");
+MODULE_SOFTDEP("ccm");
+MODULE_SOFTDEP("gcm");
+module_init(init_cifs)
+module_exit(exit_cifs)