1 files changed, 98 insertions, 0 deletions
diff --git a/fs/smb/client/cached_dir.h b/fs/smb/client/cached_dir.h
new file mode 100644
index 000000000000..1e383db7c337
--- /dev/null
+++ b/fs/smb/client/cached_dir.h
@@ -0,0 +1,98 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ *  Functions to handle the cached directory entries
+ *
+ *  Copyright (c) 2022, Ronnie Sahlberg <lsahlber@redhat.com>
+ */
+
+#ifndef _CACHED_DIR_H
+#define _CACHED_DIR_H
+
+
+struct cached_dirent {
+	struct list_head entry;
+	char *name;
+	int namelen;
+	loff_t pos;
+	struct cifs_fattr fattr;
+};
+
+struct cached_dirents {
+	bool is_valid:1;
+	bool is_failed:1;
+	struct file *file; /*
+			    * Used to associate the cache with a single
+			    * open file instance.
+			    */
+	struct mutex de_mutex;
+	loff_t pos;		 /* Expected ctx->pos */
+	struct list_head entries;
+	/* accounting for cached entries in this directory */
+	unsigned long entries_count;
+	unsigned long bytes_used;
+};
+
+struct cached_fid {
+	struct list_head entry;
+	struct cached_fids *cfids;
+	const char *path;
+	bool has_lease:1;
+	bool is_open:1;
+	bool on_list:1;
+	bool file_all_info_is_valid:1;
+	unsigned long time; /* jiffies of when lease was taken */
+	unsigned long last_access_time; /* jiffies of when last accessed */
+	struct kref refcount;
+	struct cifs_fid fid;
+	struct cifs_tcon *tcon;
+	struct dentry *dentry;
+	struct work_struct put_work;
+	struct work_struct close_work;
+	struct smb2_file_all_info file_all_info;
+	struct cached_dirents dirents;
+};
+
+/* default MAX_CACHED_FIDS is 16 */
+struct cached_fids {
+	/* Must be held when:
+	 * - accessing the cfids->entries list
+	 * - accessing the cfids->dying list
+	 */
+	spinlock_t cfid_list_lock;
+	int num_entries;
+	struct list_head entries;
+	struct list_head dying;
+	struct delayed_work laundromat_work;
+	/* aggregate accounting for all cached dirents under this tcon */
+	atomic_long_t total_dirents_entries;
+	atomic64_t total_dirents_bytes;
+};
+
+/* Module-wide directory cache accounting (defined in cifsfs.c) */
+extern atomic64_t cifs_dircache_bytes_used; /* bytes across all mounts */
+
+static inline bool
+is_valid_cached_dir(struct cached_fid *cfid)
+{
+	return cfid->time && cfid->has_lease;
+}
+
+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,
+			   bool lookup_only, struct cached_fid **cfid);
+extern int open_cached_dir_by_dentry(struct cifs_tcon *tcon,
+				     struct dentry *dentry,
+				     struct cached_fid **cfid);
+extern void close_cached_dir(struct cached_fid *cfid);
+extern void drop_cached_dir_by_name(const unsigned int xid,
+				    struct cifs_tcon *tcon,
+				    const char *name,
+				    struct cifs_sb_info *cifs_sb);
+extern void close_all_cached_dirs(struct cifs_sb_info *cifs_sb);
+extern void invalidate_all_cached_dirs(struct cifs_tcon *tcon);
+extern bool cached_dir_lease_break(struct cifs_tcon *tcon, __u8 lease_key[16]);
+
+#endif			/* _CACHED_DIR_H */