Merge tag '5.6-smb3-fixes-and-dfs-and-readdir-improvements' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs updates from Steve French:
 "Various SMB3/CIFS fixes including four for stable.

   - Improvement to fallocate (enables 3 additional xfstests)

   - Fix for file creation when mounting with modefromsid

   - Add ability to backup/restore dos attributes and creation time

   - DFS failover and reconnect fixes

   - performance optimization for readir

  Note that due to the upcoming SMB3 Test Event (at SNIA SDC next week)
  there will likely be more changesets near the end of the merge window
  (since we will be testing heavily next week, I held off on some
  patches and I expect some additional multichannel patches as well as
  patches to enable some additional xfstests)"

* tag '5.6-smb3-fixes-and-dfs-and-readdir-improvements' of git://git.samba.org/sfrench/cifs-2.6: (24 commits)
  CIFS: Fix task struct use-after-free on reconnect
  cifs: use PTR_ERR_OR_ZERO() to simplify code
  cifs: add support for fallocate mode 0 for non-sparse files
  cifs: fix NULL dereference in match_prepath
  smb3: fix default permissions on new files when mounting with modefromsid
  CIFS: Add support for setting owner info, dos attributes, and create time
  cifs: remove set but not used variable 'server'
  cifs: Fix memory allocation in __smb2_handle_cancelled_cmd()
  cifs: Fix mount options set in automount
  cifs: fix unitialized variable poential problem with network I/O cache lock patch
  cifs: Fix return value in __update_cache_entry
  cifs: Avoid doing network I/O while holding cache lock
  cifs: Fix potential deadlock when updating vol in cifs_reconnect()
  cifs: Merge is_path_valid() into get_normalized_path()
  cifs: Introduce helpers for finding TCP connection
  cifs: Get rid of kstrdup_const()'d paths
  cifs: Clean up DFS referral cache
  cifs: Don't use iov_iter::type directly
  cifs: set correct max-buffer-size for smb2_ioctl_init()
  cifs: use compounding for open and first query-dir for readdir()
  ...

18 files changed, 1041 insertions, 713 deletions

diff --git a/fs/cifs/cifs_dfs_ref.c b/fs/cifs/cifs_dfs_ref.c
index 41957b82d796..606f26d862dc 100644
--- a/fs/cifs/cifs_dfs_ref.c
+++ b/fs/cifs/cifs_dfs_ref.c
@@ -120,17 +120,17 @@ cifs_build_devname(char *nodename, const char *prepath)
 
 
 /**
- * cifs_compose_mount_options	-	creates mount options for refferral
+ * cifs_compose_mount_options	-	creates mount options for referral
  * @sb_mountdata:	parent/root DFS mount options (template)
  * @fullpath:		full path in UNC format
- * @ref:		server's referral
+ * @ref:		optional server's referral
  * @devname:		optional pointer for saving device name
  *
  * 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.
  *
  * Returns: pointer to new mount options or ERR_PTR.
- * Caller is responcible for freeing retunrned value if it is not error.
+ * Caller is responsible for freeing returned value if it is not error.
  */
 char *cifs_compose_mount_options(const char *sb_mountdata,
 				   const char *fullpath,
@@ -150,18 +150,27 @@ char *cifs_compose_mount_options(const char *sb_mountdata,
 	if (sb_mountdata == NULL)
 		return ERR_PTR(-EINVAL);
 
-	if (strlen(fullpath) - ref->path_consumed) {
-		prepath = fullpath + ref->path_consumed;
-		/* skip initial delimiter */
-		if (*prepath == '/' || *prepath == '\\')
-			prepath++;
-	}
+	if (ref) {
+		if (strlen(fullpath) - ref->path_consumed) {
+			prepath = fullpath + ref->path_consumed;
+			/* skip initial delimiter */
+			if (*prepath == '/' || *prepath == '\\')
+				prepath++;
+		}
 
-	name = cifs_build_devname(ref->node_name, prepath);
-	if (IS_ERR(name)) {
-		rc = PTR_ERR(name);
-		name = NULL;
-		goto compose_mount_options_err;
+		name = cifs_build_devname(ref->node_name, prepath);
+		if (IS_ERR(name)) {
+			rc = PTR_ERR(name);
+			name = NULL;
+			goto compose_mount_options_err;
+		}
+	} else {
+		name = cifs_build_devname((char *)fullpath, NULL);
+		if (IS_ERR(name)) {
+			rc = PTR_ERR(name);
+			name = NULL;
+			goto compose_mount_options_err;
+		}
 	}
 
 	rc = dns_resolve_server_name_to_ip(name, &srvIP);
@@ -225,6 +234,8 @@ char *cifs_compose_mount_options(const char *sb_mountdata,
 
 	if (devname)
 		*devname = name;
+	else
+		kfree(name);
 
 	/*cifs_dbg(FYI, "%s: parent mountdata: %s\n", __func__, sb_mountdata);*/
 	/*cifs_dbg(FYI, "%s: submount mountdata: %s\n", __func__, mountdata );*/
@@ -241,23 +252,23 @@ compose_mount_options_err:
 }
 
 /**
- * cifs_dfs_do_refmount - mounts specified path using provided refferal
+ * cifs_dfs_do_mount - mounts specified path using DFS full path
+ *
+ * Always pass down @fullpath to smb3_do_mount() so we can use the root server
+ * to perform failover in case we failed to connect to the first target in the
+ * referral.
+ *
  * @cifs_sb:		parent/root superblock
  * @fullpath:		full path in UNC format
- * @ref:		server's referral
  */
-static struct vfsmount *cifs_dfs_do_refmount(struct dentry *mntpt,
-		struct cifs_sb_info *cifs_sb,
-		const char *fullpath, const struct dfs_info3_param *ref)
+static struct vfsmount *cifs_dfs_do_mount(struct dentry *mntpt,
+					  struct cifs_sb_info *cifs_sb,
+					  const char *fullpath)
 {
 	struct vfsmount *mnt;
 	char *mountdata;
 	char *devname;
 
-	/*
-	 * Always pass down the DFS full path to smb3_do_mount() so we
-	 * can use it later for failover.
-	 */
 	devname = kstrndup(fullpath, strlen(fullpath), GFP_KERNEL);
 	if (!devname)
 		return ERR_PTR(-ENOMEM);
@@ -266,7 +277,7 @@ static struct vfsmount *cifs_dfs_do_refmount(struct dentry *mntpt,
 
 	/* strip first '\' from fullpath */
 	mountdata = cifs_compose_mount_options(cifs_sb->mountdata,
-					       fullpath + 1, ref, NULL);
+					       fullpath + 1, NULL, NULL);
 	if (IS_ERR(mountdata)) {
 		kfree(devname);
 		return (struct vfsmount *)mountdata;
@@ -278,28 +289,16 @@ static struct vfsmount *cifs_dfs_do_refmount(struct dentry *mntpt,
 	return mnt;
 }
 
-static void dump_referral(const struct dfs_info3_param *ref)
-{
-	cifs_dbg(FYI, "DFS: ref path: %s\n", ref->path_name);
-	cifs_dbg(FYI, "DFS: node path: %s\n", ref->node_name);
-	cifs_dbg(FYI, "DFS: fl: %d, srv_type: %d\n",
-		 ref->flags, ref->server_type);
-	cifs_dbg(FYI, "DFS: ref_flags: %d, path_consumed: %d\n",
-		 ref->ref_flag, ref->path_consumed);
-}
-
 /*
  * Create a vfsmount that we can automount
  */
 static struct vfsmount *cifs_dfs_do_automount(struct dentry *mntpt)
 {
-	struct dfs_info3_param referral = {0};
 	struct cifs_sb_info *cifs_sb;
 	struct cifs_ses *ses;
 	struct cifs_tcon *tcon;
 	char *full_path, *root_path;
 	unsigned int xid;
-	int len;
 	int rc;
 	struct vfsmount *mnt;
 
@@ -357,7 +356,7 @@ static struct vfsmount *cifs_dfs_do_automount(struct dentry *mntpt)
 	if (!rc) {
 		rc = dfs_cache_find(xid, ses, cifs_sb->local_nls,
 				    cifs_remap(cifs_sb), full_path + 1,
-				    &referral, NULL);
+				    NULL, NULL);
 	}
 
 	free_xid(xid);
@@ -366,26 +365,16 @@ static struct vfsmount *cifs_dfs_do_automount(struct dentry *mntpt)
 		mnt = ERR_PTR(rc);
 		goto free_root_path;
 	}
-
-	dump_referral(&referral);
-
-	len = strlen(referral.node_name);
-	if (len < 2) {
-		cifs_dbg(VFS, "%s: Net Address path too short: %s\n",
-			 __func__, referral.node_name);
-		mnt = ERR_PTR(-EINVAL);
-		goto free_dfs_ref;
-	}
 	/*
-	 * cifs_mount() will retry every available node server in case
-	 * of failures.
+	 * OK - we were able to get and cache a referral for @full_path.
+	 *
+	 * Now, pass it down to cifs_mount() and it will retry every available
+	 * node server in case of failures - no need to do it here.
 	 */
-	mnt = cifs_dfs_do_refmount(mntpt, cifs_sb, full_path, &referral);
-	cifs_dbg(FYI, "%s: cifs_dfs_do_refmount:%s , mnt:%p\n", __func__,
-		 referral.node_name, mnt);
+	mnt = cifs_dfs_do_mount(mntpt, cifs_sb, full_path);
+	cifs_dbg(FYI, "%s: cifs_dfs_do_mount:%s , mnt:%p\n", __func__,
+		 full_path + 1, mnt);
 
-free_dfs_ref:
-	free_dfs_info_param(&referral);
 free_root_path:
 	kfree(root_path);
 free_full_path:
diff --git a/fs/cifs/cifsacl.c b/fs/cifs/cifsacl.c
index 96ae72b556ac..fb41e51dd574 100644
--- a/fs/cifs/cifsacl.c
+++ b/fs/cifs/cifsacl.c
@@ -802,6 +802,26 @@ static void parse_dacl(struct cifs_acl *pdacl, char *end_of_acl,
 	return;
 }
 
+unsigned int setup_authusers_ACE(struct cifs_ace *pntace)
+{
+	int i;
+	unsigned int ace_size = 20;
+
+	pntace->type = ACCESS_ALLOWED_ACE_TYPE;
+	pntace->flags = 0x0;
+	pntace->access_req = cpu_to_le32(GENERIC_ALL);
+	pntace->sid.num_subauth = 1;
+	pntace->sid.revision = 1;
+	for (i = 0; i < NUM_AUTHS; i++)
+		pntace->sid.authority[i] =  sid_authusers.authority[i];
+
+	pntace->sid.sub_auth[0] =  sid_authusers.sub_auth[0];
+
+	/* size = 1 + 1 + 2 + 4 + 1 + 1 + 6 + (psid->num_subauth*4) */
+	pntace->size = cpu_to_le16(ace_size);
+	return ace_size;
+}
+
 /*
  * Fill in the special SID based on the mode. See
  * http://technet.microsoft.com/en-us/library/hh509017(v=ws.10).aspx
diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h
index b59dc7478130..096a4c18fbd0 100644
--- a/fs/cifs/cifsfs.h
+++ b/fs/cifs/cifsfs.h
@@ -149,6 +149,9 @@ extern ssize_t cifs_file_copychunk_range(unsigned int xid,
 					size_t len, unsigned int flags);
 
 extern long cifs_ioctl(struct file *filep, unsigned int cmd, unsigned long arg);
+extern void cifs_setsize(struct inode *inode, loff_t offset);
+extern int cifs_truncate_page(struct address_space *mapping, loff_t from);
+
 #ifdef CONFIG_CIFS_NFSD_EXPORT
 extern const struct export_operations cifs_export_ops;
 #endif /* CONFIG_CIFS_NFSD_EXPORT */
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 40705e862451..239338d57086 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -1588,6 +1588,7 @@ struct mid_q_entry {
 	mid_callback_t *callback; /* call completion callback */
 	mid_handle_t *handle; /* call handle mid callback */
 	void *callback_data;	  /* general purpose pointer for callback */
+	struct task_struct *creator;
 	void *resp_buf;		/* pointer to received SMB header */
 	unsigned int resp_buf_size;
 	int mid_state;	/* wish this were enum but can not pass to wait_event */
diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index 9c229408a251..948bf3474db1 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -213,6 +213,7 @@ extern struct cifs_ntsd *get_cifs_acl_by_fid(struct cifs_sb_info *,
 						const struct cifs_fid *, u32 *);
 extern int set_cifs_acl(struct cifs_ntsd *, __u32, struct inode *,
 				const char *, int);
+extern unsigned int setup_authusers_ACE(struct cifs_ace *pace);
 extern unsigned int setup_special_mode_ACE(struct cifs_ace *pace, __u64 nmode);
 
 extern void dequeue_mid(struct mid_q_entry *mid, bool malformed);
@@ -596,6 +597,9 @@ bool is_ses_using_iface(struct cifs_ses *ses, struct cifs_server_iface *iface);
 
 void extract_unc_hostname(const char *unc, const char **h, size_t *len);
 int copy_path_name(char *dst, const char *src);
+int smb2_parse_query_directory(struct cifs_tcon *tcon, struct kvec *rsp_iov,
+			       int resp_buftype,
+			       struct cifs_search_info *srch_inf);
 
 #ifdef CONFIG_CIFS_DFS_UPCALL
 static inline int get_dfs_path(const unsigned int xid, struct cifs_ses *ses,
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index cc86a67225d1..a481296f417f 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -4619,7 +4619,7 @@ findFirstRetry:
 				psrch_inf->unicode = false;
 
 			psrch_inf->ntwrk_buf_start = (char *)pSMBr;
-			psrch_inf->smallBuf = 0;
+			psrch_inf->smallBuf = false;
 			psrch_inf->srch_entries_start =
 				(char *) &pSMBr->hdr.Protocol +
 					le16_to_cpu(pSMBr->t2.DataOffset);
@@ -4753,7 +4753,7 @@ int CIFSFindNext(const unsigned int xid, struct cifs_tcon *tcon,
 				cifs_buf_release(psrch_inf->ntwrk_buf_start);
 			psrch_inf->srch_entries_start = response_data;
 			psrch_inf->ntwrk_buf_start = (char *)pSMB;
-			psrch_inf->smallBuf = 0;
+			psrch_inf->smallBuf = false;
 			if (parms->EndofSearch)
 				psrch_inf->endOfSearch = true;
 			else
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 05ea0e2b7e0e..0aa3623ae0e1 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -3709,8 +3709,10 @@ match_prepath(struct super_block *sb, struct cifs_mnt_data *mnt_data)
 {
 	struct cifs_sb_info *old = CIFS_SB(sb);
 	struct cifs_sb_info *new = mnt_data->cifs_sb;
-	bool old_set = old->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH;
-	bool new_set = new->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH;
+	bool old_set = (old->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
+		old->prepath;
+	bool new_set = (new->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
+		new->prepath;
 
 	if (old_set && new_set && !strcmp(new->prepath, old->prepath))
 		return 1;
diff --git a/fs/cifs/dfs_cache.c b/fs/cifs/dfs_cache.c
index 2faa05860a48..9a384d1e27b4 100644
--- a/fs/cifs/dfs_cache.c
+++ b/fs/cifs/dfs_cache.c
@@ -5,8 +5,6 @@
  * Copyright (c) 2018-2019 Paulo Alcantara <palcantara@suse.de>
  */
 
-#include <linux/rcupdate.h>
-#include <linux/rculist.h>
 #include <linux/jhash.h>
 #include <linux/ktime.h>
 #include <linux/slab.h>
@@ -22,67 +20,68 @@
 
 #include "dfs_cache.h"
 
-#define DFS_CACHE_HTABLE_SIZE 32
-#define DFS_CACHE_MAX_ENTRIES 64
+#define CACHE_HTABLE_SIZE 32
+#define CACHE_MAX_ENTRIES 64
 
 #define IS_INTERLINK_SET(v) ((v) & (DFSREF_REFERRAL_SERVER | \
 				    DFSREF_STORAGE_SERVER))
 
-struct dfs_cache_tgt {
-	char *t_name;
-	struct list_head t_list;
+struct cache_dfs_tgt {
+	char *name;
+	struct list_head list;
 };
 
-struct dfs_cache_entry {
-	struct hlist_node ce_hlist;
-	const char *ce_path;
-	int ce_ttl;
-	int ce_srvtype;
-	int ce_flags;
-	struct timespec64 ce_etime;
-	int ce_path_consumed;
-	int ce_numtgts;
-	struct list_head ce_tlist;
-	struct dfs_cache_tgt *ce_tgthint;
-	struct rcu_head ce_rcu;
+struct cache_entry {
+	struct hlist_node hlist;
+	const char *path;
+	int ttl;
+	int srvtype;
+	int flags;
+	struct timespec64 etime;
+	int path_consumed;
+	int numtgts;
+	struct list_head tlist;
+	struct cache_dfs_tgt *tgthint;
 };
 
-static struct kmem_cache *dfs_cache_slab __read_mostly;
-
-struct dfs_cache_vol_info {
-	char *vi_fullpath;
-	struct smb_vol vi_vol;
-	char *vi_mntdata;
-	struct list_head vi_list;
+struct vol_info {
+	char *fullpath;
+	spinlock_t smb_vol_lock;
+	struct smb_vol smb_vol;
+	char *mntdata;
+	struct list_head list;
+	struct list_head rlist;
+	struct kref refcnt;
 };
 
-struct dfs_cache {
-	struct mutex dc_lock;
-	struct nls_table *dc_nlsc;
-	struct list_head dc_vol_list;
-	int dc_ttl;
-	struct delayed_work dc_refresh;
-};
+static struct kmem_cache *cache_slab __read_mostly;
+static struct workqueue_struct *dfscache_wq __read_mostly;
 
-static struct dfs_cache dfs_cache;
+static int cache_ttl;
+static DEFINE_SPINLOCK(cache_ttl_lock);
+
+static struct nls_table *cache_nlsc;
 
 /*
  * Number of entries in the cache
  */
-static size_t dfs_cache_count;
+static atomic_t cache_count;
+
+static struct hlist_head cache_htable[CACHE_HTABLE_SIZE];
+static DECLARE_RWSEM(htable_rw_lock);
 
-static DEFINE_MUTEX(dfs_cache_list_lock);
-static struct hlist_head dfs_cache_htable[DFS_CACHE_HTABLE_SIZE];
+static LIST_HEAD(vol_list);
+static DEFINE_SPINLOCK(vol_list_lock);
 
 static void refresh_cache_worker(struct work_struct *work);
 
-static inline bool is_path_valid(const char *path)
-{
-	return path && (strchr(path + 1, '\\') || strchr(path + 1, '/'));
-}
+static DECLARE_DELAYED_WORK(refresh_task, refresh_cache_worker);
 
-static inline int get_normalized_path(const char *path, char **npath)
+static int get_normalized_path(const char *path, char **npath)
 {
+	if (!path || strlen(path) < 3 || (*path != '\\' && *path != '/'))
+		return -EINVAL;
+
 	if (*path == '\\') {
 		*npath = (char *)path;
 	} else {
@@ -100,57 +99,48 @@ static inline void free_normalized_path(const char *path, char *npath)
 		kfree(npath);
 }
 
-static inline bool cache_entry_expired(const struct dfs_cache_entry *ce)
+static inline bool cache_entry_expired(const struct cache_entry *ce)
 {
 	struct timespec64 ts;
 
 	ktime_get_coarse_real_ts64(&ts);
-	return timespec64_compare(&ts, &ce->ce_etime) >= 0;
+	return timespec64_compare(&ts, &ce->etime) >= 0;
 }
 
-static inline void free_tgts(struct dfs_cache_entry *ce)
+static inline void free_tgts(struct cache_entry *ce)
 {
-	struct dfs_cache_tgt *t, *n;
+	struct cache_dfs_tgt *t, *n;
 
-	list_for_each_entry_safe(t, n, &ce->ce_tlist, t_list) {
-		list_del(&t->t_list);
-		kfree(t->t_name);
+	list_for_each_entry_safe(t, n, &ce->tlist, list) {
+		list_del(&t->list);
+		kfree(t->name);
 		kfree(t);
 	}
 }
 
-static void free_cache_entry(struct rcu_head *rcu)
+static inline void flush_cache_ent(struct cache_entry *ce)
 {
-	struct dfs_cache_entry *ce = container_of(rcu, struct dfs_cache_entry,
-						  ce_rcu);
-	kmem_cache_free(dfs_cache_slab, ce);
-}
-
-static inline void flush_cache_ent(struct dfs_cache_entry *ce)
-{
-	if (hlist_unhashed(&ce->ce_hlist))
-		return;
-
-	hlist_del_init_rcu(&ce->ce_hlist);
-	kfree_const(ce->ce_path);
+	hlist_del_init(&ce->hlist);
+	kfree(ce->path);
 	free_tgts(ce);
-	dfs_cache_count--;
-	call_rcu(&ce->ce_rcu, free_cache_entry);
+	atomic_dec(&cache_count);
+	kmem_cache_free(cache_slab, ce);
 }
 
 static void flush_cache_ents(void)
 {
 	int i;
 
-	rcu_read_lock();
-	for (i = 0; i < DFS_CACHE_HTABLE_SIZE; i++) {
-		struct hlist_head *l = &dfs_cache_htable[i];
-		struct dfs_cache_entry *ce;
+	for (i = 0; i < CACHE_HTABLE_SIZE; i++) {
+		struct hlist_head *l = &cache_htable[i];
+		struct hlist_node *n;
+		struct cache_entry *ce;
 
-		hlist_for_each_entry_rcu(ce, l, ce_hlist)
-			flush_cache_ent(ce);
+		hlist_for_each_entry_safe(ce, n, l, hlist) {
+			if (!hlist_unhashed(&ce->hlist))
+				flush_cache_ent(ce);
+		}
 	}
-	rcu_read_unlock();
 }
 
 /*
@@ -158,36 +148,39 @@ static void flush_cache_ents(void)
  */
 static int dfscache_proc_show(struct seq_file *m, void *v)
 {
-	int bucket;
-	struct dfs_cache_entry *ce;
-	struct dfs_cache_tgt *t;
+	int i;
+	struct cache_entry *ce;
+	struct cache_dfs_tgt *t;
 
 	seq_puts(m, "DFS cache\n---------\n");
 
-	mutex_lock(&dfs_cache_list_lock);
-
-	rcu_read_lock();
-	hash_for_each_rcu(dfs_cache_htable, bucket, ce, ce_hlist) {
-		seq_printf(m,
-			   "cache entry: path=%s,type=%s,ttl=%d,etime=%ld,"
-			   "interlink=%s,path_consumed=%d,expired=%s\n",
-			   ce->ce_path,
-			   ce->ce_srvtype == DFS_TYPE_ROOT ? "root" : "link",
-			   ce->ce_ttl, ce->ce_etime.tv_nsec,
-			   IS_INTERLINK_SET(ce->ce_flags) ? "yes" : "no",
-			   ce->ce_path_consumed,
-			   cache_entry_expired(ce) ? "yes" : "no");
-
-		list_for_each_entry(t, &ce->ce_tlist, t_list) {
-			seq_printf(m, "  %s%s\n",
-				   t->t_name,
-				   ce->ce_tgthint == t ? " (target hint)" : "");
+	down_read(&htable_rw_lock);
+	for (i = 0; i < CACHE_HTABLE_SIZE; i++) {
+		struct hlist_head *l = &cache_htable[i];
+
+		hlist_for_each_entry(ce, l, hlist) {
+			if (hlist_unhashed(&ce->hlist))
+				continue;
+
+			seq_printf(m,
+				   "cache entry: path=%s,type=%s,ttl=%d,etime=%ld,"
+				   "interlink=%s,path_consumed=%d,expired=%s\n",
+				   ce->path,
+				   ce->srvtype == DFS_TYPE_ROOT ? "root" : "link",
+				   ce->ttl, ce->etime.tv_nsec,
+				   IS_INTERLINK_SET(ce->flags) ? "yes" : "no",
+				   ce->path_consumed,
+				   cache_entry_expired(ce) ? "yes" : "no");
+
+			list_for_each_entry(t, &ce->tlist, list) {
+				seq_printf(m, "  %s%s\n",
+					   t->name,
+					   ce->tgthint == t ? " (target hint)" : "");
+			}
 		}
-
 	}
-	rcu_read_unlock();
+	up_read(&htable_rw_lock);
 
-	mutex_unlock(&dfs_cache_list_lock);
 	return 0;
 }
 
@@ -205,9 +198,10 @@ static ssize_t dfscache_proc_write(struct file *file, const char __user *buffer,
 		return -EINVAL;
 
 	cifs_dbg(FYI, "clearing dfs cache");
-	mutex_lock(&dfs_cache_list_lock);
+
+	down_write(&htable_rw_lock);
 	flush_cache_ents();
-	mutex_unlock(&dfs_cache_list_lock);
+	up_write(&htable_rw_lock);
 
 	return count;
 }
@@ -226,25 +220,25 @@ const struct file_operations dfscache_proc_fops = {
 };
 
 #ifdef CONFIG_CIFS_DEBUG2
-static inline void dump_tgts(const struct dfs_cache_entry *ce)
+static inline void dump_tgts(const struct cache_entry *ce)
 {
-	struct dfs_cache_tgt *t;
+	struct cache_dfs_tgt *t;
 
 	cifs_dbg(FYI, "target list:\n");
-	list_for_each_entry(t, &ce->ce_tlist, t_list) {
-		cifs_dbg(FYI, "  %s%s\n", t->t_name,
-			 ce->ce_tgthint == t ? " (target hint)" : "");
+	list_for_each_entry(t, &ce->tlist, list) {
+		cifs_dbg(FYI, "  %s%s\n", t->name,
+			 ce->tgthint == t ? " (target hint)" : "");
 	}
 }
 
-static inline void dump_ce(const struct dfs_cache_entry *ce)
+static inline void dump_ce(const struct cache_entry *ce)
 {
 	cifs_dbg(FYI, "cache entry: path=%s,type=%s,ttl=%d,etime=%ld,"
-		 "interlink=%s,path_consumed=%d,expired=%s\n", ce->ce_path,
-		 ce->ce_srvtype == DFS_TYPE_ROOT ? "root" : "link", ce->ce_ttl,
-		 ce->ce_etime.tv_nsec,
-		 IS_INTERLINK_SET(ce->ce_flags) ? "yes" : "no",
-		 ce->ce_path_consumed,
+		 "interlink=%s,path_consumed=%d,expired=%s\n", ce->path,
+		 ce->srvtype == DFS_TYPE_ROOT ? "root" : "link", ce->ttl,
+		 ce->etime.tv_nsec,
+		 IS_INTERLINK_SET(ce->flags) ? "yes" : "no",
+		 ce->path_consumed,
 		 cache_entry_expired(ce) ? "yes" : "no");
 	dump_tgts(ce);
 }
@@ -284,25 +278,34 @@ static inline void dump_refs(const struct dfs_info3_param *refs, int numrefs)
  */
 int dfs_cache_init(void)
 {
+	int rc;
 	int i;
 
-	dfs_cache_slab = kmem_cache_create("cifs_dfs_cache",
-					   sizeof(struct dfs_cache_entry), 0,
-					   SLAB_HWCACHE_ALIGN, NULL);
-	if (!dfs_cache_slab)
+	dfscache_wq = alloc_workqueue("cifs-dfscache",
+				      WQ_FREEZABLE | WQ_MEM_RECLAIM, 1);
+	if (!dfscache_wq)
 		return -ENOMEM;
 
-	for (i = 0; i < DFS_CACHE_HTABLE_SIZE; i++)
-		INIT_HLIST_HEAD(&dfs_cache_htable[i]);
+	cache_slab = kmem_cache_create("cifs_dfs_cache",
+				       sizeof(struct cache_entry), 0,
+				       SLAB_HWCACHE_ALIGN, NULL);
+	if (!cache_slab) {
+		rc = -ENOMEM;
+		goto out_destroy_wq;
+	}
+
+	for (i = 0; i < CACHE_HTABLE_SIZE; i++)
+		INIT_HLIST_HEAD(&cache_htable[i]);
 
-	INIT_LIST_HEAD(&dfs_cache.dc_vol_list);
-	mutex_init(&dfs_cache.dc_lock);
-	INIT_DELAYED_WORK(&dfs_cache.dc_refresh, refresh_cache_worker);
-	dfs_cache.dc_ttl = -1;
-	dfs_cache.dc_nlsc = load_nls_default();
+	atomic_set(&cache_count, 0);
+	cache_nlsc = load_nls_default();
 
 	cifs_dbg(FYI, "%s: initialized DFS referral cache\n", __func__);
 	return 0;
+
+out_destroy_wq:
+	destroy_workqueue(dfscache_wq);
+	return rc;
 }
 
 static inline unsigned int cache_entry_hash(const void *data, int size)
@@ -310,7 +313,7 @@ static inline unsigned int cache_entry_hash(const void *data, int size)
 	unsigned int h;
 
 	h = jhash(data, size, 0);
-	return h & (DFS_CACHE_HTABLE_SIZE - 1);
+	return h & (CACHE_HTABLE_SIZE - 1);
 }
 
 /* Check whether second path component of @path is SYSVOL or NETLOGON */
@@ -325,11 +328,11 @@ static inline bool is_sysvol_or_netlogon(const char *path)
 }
 
 /* Return target hint of a DFS cache entry */
-static inline char *get_tgt_name(const struct dfs_cache_entry *ce)
+static inline char *get_tgt_name(const struct cache_entry *ce)
 {
-	struct dfs_cache_tgt *t = ce->ce_tgthint;
+	struct cache_dfs_tgt *t = ce->tgthint;
 
-	return t ? t->t_name : ERR_PTR(-ENOENT);
+	return t ? t->name : ERR_PTR(-ENOENT);
 }
 
 /* Return expire time out of a new entry's TTL */
@@ -346,19 +349,19 @@ static inline struct timespec64 get_expire_time(int ttl)
 }
 
 /* Allocate a new DFS target */
-static inline struct dfs_cache_tgt *alloc_tgt(const char *name)
+static struct cache_dfs_tgt *alloc_target(const char *name)
 {
-	struct dfs_cache_tgt *t;
+	struct cache_dfs_tgt *t;
 
-	t = kmalloc(sizeof(*t), GFP_KERNEL);
+	t = kmalloc(sizeof(*t), GFP_ATOMIC);
 	if (!t)
 		return ERR_PTR(-ENOMEM);
-	t->t_name = kstrndup(name, strlen(name), GFP_KERNEL);
-	if (!t->t_name) {
+	t->name = kstrndup(name, strlen(name), GFP_ATOMIC);
+	if (!t->name) {
 		kfree(t);
 		return ERR_PTR(-ENOMEM);
 	}
-	INIT_LIST_HEAD(&t->t_list);
+	INIT_LIST_HEAD(&t->list);
 	return t;
 }
 
@@ -367,180 +370,184 @@ static inline struct dfs_cache_tgt *alloc_tgt(const char *name)
  * target hint.
  */
 static int copy_ref_data(const struct dfs_info3_param *refs, int numrefs,
-			 struct dfs_cache_entry *ce, const char *tgthint)
+			 struct cache_entry *ce, const char *tgthint)
 {
 	int i;
 
-	ce->ce_ttl = refs[0].ttl;
-	ce->ce_etime = get_expire_time(ce->ce_ttl);
-	ce->ce_srvtype = refs[0].server_type;
-	ce->ce_flags = refs[0].ref_flag;
-	ce->ce_path_consumed = refs[0].path_consumed;
+	ce->ttl = refs[0].ttl;
+	ce->etime = get_expire_time(ce->ttl);
+	ce->srvtype = refs[0].server_type;
+	ce->flags = refs[0].ref_flag;
+	ce->path_consumed = refs[0].path_consumed;
 
 	for (i = 0; i < numrefs; i++) {
-		struct dfs_cache_tgt *t;
+		struct cache_dfs_tgt *t;
 
-		t = alloc_tgt(refs[i].node_name);
+		t = alloc_target(refs[i].node_name);
 		if (IS_ERR(t)) {
 			free_tgts(ce);
 			return PTR_ERR(t);
 		}
-		if (tgthint && !strcasecmp(t->t_name, tgthint)) {
-			list_add(&t->t_list, &ce->ce_tlist);
+		if (tgthint && !strcasecmp(t->name, tgthint)) {
+			list_add(&t->list, &ce->tlist);
 			tgthint = NULL;
 		} else {
-			list_add_tail(&t->t_list, &ce->ce_tlist);
+			list_add_tail(&t->list, &ce->tlist);
 		}
-		ce->ce_numtgts++;
+		ce->numtgts++;
 	}
 
-	ce->ce_tgthint = list_first_entry_or_null(&ce->ce_tlist,
-						  struct dfs_cache_tgt, t_list);
+	ce->tgthint = list_first_entry_or_null(&ce->tlist,
+					       struct cache_dfs_tgt, list);
 
 	return 0;
 }
 
 /* Allocate a new cache entry */
-static struct dfs_cache_entry *
-alloc_cache_entry(const char *path, const struct dfs_info3_param *refs,
-		  int numrefs)
+static struct cache_entry *alloc_cache_entry(const char *path,
+					     const struct dfs_info3_param *refs,
+					     int numrefs)
 {
-	struct dfs_cache_entry *ce;
+	struct cache_entry *ce;
 	int rc;
 
-	ce = kmem_cache_zalloc(dfs_cache_slab, GFP_KERNEL);
+	ce = kmem_cache_zalloc(cache_slab, GFP_KERNEL);
 	if (!ce)
 		return ERR_PTR(-ENOMEM);
 
-	ce->ce_path = kstrdup_const(path, GFP_KERNEL);
-	if (!ce->ce_path) {
-		kmem_cache_free(dfs_cache_slab, ce);
+	ce->path = kstrndup(path, strlen(path), GFP_KERNEL);
+	if (!ce->path) {
+		kmem_cache_free(cache_slab, ce);
 		return ERR_PTR(-ENOMEM);
 	}
-	INIT_HLIST_NODE(&ce->ce_hlist);
-	INIT_LIST_HEAD(&ce->ce_tlist);
+	INIT_HLIST_NODE(&ce->hlist);
+	INIT_LIST_HEAD(&ce->tlist);
 
 	rc = copy_ref_data(refs, numrefs, ce, NULL);
 	if (rc) {
-		kfree_const(ce->ce_path);
-		kmem_cache_free(dfs_cache_slab, ce);
+		kfree(ce->path);
+		kmem_cache_free(cache_slab, ce);
 		ce = ERR_PTR(rc);
 	}
 	return ce;
 }
 
+/* Must be called with htable_rw_lock held */
 static void remove_oldest_entry(void)
 {
-	int bucket;
-	struct dfs_cache_entry *ce;
-	struct dfs_cache_entry *to_del = NULL;
-
-	rcu_read_lock();
-	hash_for_each_rcu(dfs_cache_htable, bucket, ce, ce_hlist) {
-		if (!to_del || timespec64_compare(&ce->ce_etime,
-						  &to_del->ce_etime) < 0)
-			to_del = ce;
+	int i;
+	struct cache_entry *ce;
+	struct cache_entry *to_del = NULL;
+
+	for (i = 0; i < CACHE_HTABLE_SIZE; i++) {
+		struct hlist_head *l = &cache_htable[i];
+
+		hlist_for_each_entry(ce, l, hlist) {
+			if (hlist_unhashed(&ce->hlist))
+				continue;
+			if (!to_del || timespec64_compare(&ce->etime,
+							  &to_del->etime) < 0)
+				to_del = ce;
+		}
 	}
+
 	if (!to_del) {
 		cifs_dbg(FYI, "%s: no entry to remove", __func__);
-		goto out;
+		return;
 	}
+
 	cifs_dbg(FYI, "%s: removing entry", __func__);
 	dump_ce(to_del);
 	flush_cache_ent(to_del);
-out:
-	rcu_read_unlock();
 }
 
 /* Add a new DFS cache entry */
-static inline struct dfs_cache_entry *
-add_cache_entry(unsigned int hash, const char *path,
-		const struct dfs_info3_param *refs, int numrefs)
+static int add_cache_entry(const char *path, unsigned int hash,
+			   struct dfs_info3_param *refs, int numrefs)
 {
-	struct dfs_cache_entry *ce;
+	struct cache_entry *ce;
 
 	ce = alloc_cache_entry(path, refs, numrefs);
 	if (IS_ERR(ce))
-		return ce;
+		return PTR_ERR(ce);
 
-	hlist_add_head_rcu(&ce->ce_hlist, &dfs_cache_htable[hash]);
-
-	mutex_lock(&dfs_cache.dc_lock);
-	if (dfs_cache.dc_ttl < 0) {
-		dfs_cache.dc_ttl = ce->ce_ttl;
-		queue_delayed_work(cifsiod_wq, &dfs_cache.dc_refresh,
-				   dfs_cache.dc_ttl * HZ);
+	spin_lock(&cache_ttl_lock);
+	if (!cache_ttl) {
+		cache_ttl = ce->ttl;
+		queue_delayed_work(dfscache_wq, &refresh_task, cache_ttl * HZ);
 	} else {
-		dfs_cache.dc_ttl = min_t(int, dfs_cache.dc_ttl, ce->ce_ttl);
-		mod_delayed_work(cifsiod_wq, &dfs_cache.dc_refresh,
-				 dfs_cache.dc_ttl * HZ);
+		cache_ttl = min_t(int, cache_ttl, ce->ttl);
+		mod_delayed_work(dfscache_wq, &refresh_task, cache_ttl * HZ);
 	}
-	mutex_unlock(&dfs_cache.dc_lock);
+	spin_unlock(&cache_ttl_lock);
 
-	return ce;
+	down_write(&htable_rw_lock);
+	hlist_add_head(&ce->hlist, &cache_htable[hash]);
+	dump_ce(ce);
+	up_write(&htable_rw_lock);
+