cifs: Make tcon contain a wrapper structure cached_fids instead of cached_fid

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2151418
commit aea6794

This wrapper structure will later be expanded to contain a list of
fids that are cached and not just the root fid.

    Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
    Signed-off-by: Steve French <stfrench@microsoft.com>
    (cherry picked from commit aea6794)
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>

Author: Ronnie Sahlberg

fs/cifs/cached_dir.c

@@ -52,7 +52,7 @@ int open_cached_dir(unsigned int xid, struct cifs_tcon *tcon,
 
 	dentry = cifs_sb->root;
 
-	cfid = tcon->cfid;
+	cfid = &tcon->cfids->cfid;
 	mutex_lock(&cfid->fid_mutex);
 	if (cfid->is_valid) {
 		cifs_dbg(FYI, "found a cached root file handle\n");
@@ -226,7 +226,7 @@ int open_cached_dir_by_dentry(struct cifs_tcon *tcon,
 {
 	struct cached_fid *cfid;
 
-	cfid = tcon->cfid;
+	cfid = &tcon->cfids->cfid;
 
 	mutex_lock(&cfid->fid_mutex);
 	if (cfid->dentry == dentry) {
@@ -320,7 +320,7 @@ void close_all_cached_dirs(struct cifs_sb_info *cifs_sb)
 		tcon = tlink_tcon(tlink);
 		if (IS_ERR(tcon))
 			continue;
-		cfid = tcon->cfid;
+		cfid = &tcon->cfids->cfid;
 		mutex_lock(&cfid->fid_mutex);
 		if (cfid->dentry) {
 			dput(cfid->dentry);
@@ -336,12 +336,14 @@ void close_all_cached_dirs(struct cifs_sb_info *cifs_sb)
  */
 void invalidate_all_cached_dirs(struct cifs_tcon *tcon)
 {
-	mutex_lock(&tcon->cfid->fid_mutex);
-	tcon->cfid->is_valid = false;
+	struct cached_fid *cfid = &tcon->cfids->cfid;
+
+	mutex_lock(&cfid->fid_mutex);
+	cfid->is_valid = false;
 	/* cached handle is not valid, so SMB2_CLOSE won't be sent below */
-	close_cached_dir_lease_locked(tcon->cfid);
-	memset(&tcon->cfid->fid, 0, sizeof(struct cifs_fid));
-	mutex_unlock(&tcon->cfid->fid_mutex);
+	close_cached_dir_lease_locked(cfid);
+	memset(&cfid->fid, 0, sizeof(struct cifs_fid));
+	mutex_unlock(&cfid->fid_mutex);
 }
 
 static void
@@ -355,34 +357,36 @@ smb2_cached_lease_break(struct work_struct *work)
 
 int cached_dir_lease_break(struct cifs_tcon *tcon, __u8 lease_key[16])
 {
-	if (tcon->cfid->is_valid &&
+	struct cached_fid *cfid = &tcon->cfids->cfid;
+
+	if (cfid->is_valid &&
 	    !memcmp(lease_key,
-		    tcon->cfid->fid.lease_key,
+		    cfid->fid.lease_key,
 		    SMB2_LEASE_KEY_SIZE)) {
-		tcon->cfid->time = 0;
-		INIT_WORK(&tcon->cfid->lease_break,
+		cfid->time = 0;
+		INIT_WORK(&cfid->lease_break,
 			  smb2_cached_lease_break);
 		queue_work(cifsiod_wq,
-			   &tcon->cfid->lease_break);
+			   &cfid->lease_break);
 		return true;
 	}
 	return false;
 }
 
-struct cached_fid *init_cached_dir(void)
+struct cached_fids *init_cached_dirs(void)
 {
-	struct cached_fid *cfid;
+	struct cached_fids *cfids;
 
-	cfid = kzalloc(sizeof(*cfid), GFP_KERNEL);
-	if (!cfid)
+	cfids = kzalloc(sizeof(*cfids), GFP_KERNEL);
+	if (!cfids)
 		return NULL;
-	INIT_LIST_HEAD(&cfid->dirents.entries);
-	mutex_init(&cfid->dirents.de_mutex);
-	mutex_init(&cfid->fid_mutex);
-	return cfid;
+	INIT_LIST_HEAD(&cfids->cfid.dirents.entries);
+	mutex_init(&cfids->cfid.dirents.de_mutex);
+	mutex_init(&cfids->cfid.fid_mutex);
+	return cfids;
 }
 
-void free_cached_dir(struct cifs_tcon *tcon)
+void free_cached_dirs(struct cached_fids *cfids)
 {
-	kfree(tcon->cfid);
+	kfree(cfids);
 }

fs/cifs/cached_dir.h

@@ -45,8 +45,12 @@ struct cached_fid {
 	struct cached_dirents dirents;
 };
 
-extern struct cached_fid *init_cached_dir(void);
-extern void free_cached_dir(struct cifs_tcon *tcon);
+struct cached_fids {
+	struct cached_fid cfid;
+};
+
+extern struct cached_fids *init_cached_dirs(void);
+extern void free_cached_dirs(struct cached_fids *cfids);
 extern int open_cached_dir(unsigned int xid, struct cifs_tcon *tcon,
 			   const char *path,
 			   struct cifs_sb_info *cifs_sb,

fs/cifs/cifsglob.h

@@ -1225,7 +1225,7 @@ struct cifs_tcon {
 	struct fscache_volume *fscache;	/* cookie for share */
 #endif
 	struct list_head pending_opens;	/* list of incomplete opens */
-	struct cached_fid *cfid; /* Cached root fid */
+	struct cached_fids *cfids;
 	/* BB add field for back pointer to sb struct(s)? */
 #ifdef CONFIG_CIFS_DFS_UPCALL
 	struct list_head ulist; /* cache update list */

fs/cifs/misc.c

@@ -117,8 +117,8 @@ tconInfoAlloc(void)
 	ret_buf = kzalloc(sizeof(*ret_buf), GFP_KERNEL);
 	if (!ret_buf)
 		return NULL;
-	ret_buf->cfid = init_cached_dir();
-	if (!ret_buf->cfid) {
+	ret_buf->cfids = init_cached_dirs();
+	if (!ret_buf->cfids) {
 		kfree(ret_buf);
 		return NULL;
 	}
@@ -144,7 +144,7 @@ tconInfoFree(struct cifs_tcon *tcon)
 		cifs_dbg(FYI, "Null buffer passed to tconInfoFree\n");
 		return;
 	}
-	free_cached_dir(tcon);
+	free_cached_dirs(tcon->cfids);
 	atomic_dec(&tconInfoAllocCount);
 	kfree(tcon->nativeFileSystem);
 	kfree_sensitive(tcon->password);