cifs: have cifsFileInfo hold a reference to a tlink rather than tcon pointer

[mirror_ubuntu-artful-kernel.git] / fs / cifs / cifsglob.h

diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index c68f31cf455061b91c605e92085ad0d556f62210..d5324853203b31489d2cb6875f3d8ade3ca65a77 100644 (file)
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -139,6 +139,7 @@ struct TCP_Server_Info {
                struct sockaddr_in sockAddr;
                struct sockaddr_in6 sockAddr6;
        } addr;
+       struct sockaddr_storage srcaddr; /* locally bind to this IP */
        wait_queue_head_t response_q;
        wait_queue_head_t request_q; /* if more than maxmpx to srvr must block*/
        struct list_head pending_mid_q;
@@ -309,6 +310,50 @@ struct cifsTconInfo {
        /* BB add field for back pointer to sb struct(s)? */
 };
 
+/*
+ * This is a refcounted and timestamped container for a tcon pointer. The
+ * container holds a tcon reference. It is considered safe to free one of
+ * these when the tl_count goes to 0. The tl_time is the time of the last
+ * "get" on the container.
+ */
+struct tcon_link {
+       spinlock_t              tl_lock;
+       u32                     tl_count;
+       u64                     tl_time;
+       struct cifsTconInfo     *tl_tcon;
+};
+
+static inline struct tcon_link *
+cifs_sb_tlink(struct cifs_sb_info *cifs_sb)
+{
+       return (struct tcon_link *)cifs_sb->ptcon;
+}
+
+static inline struct cifsTconInfo *
+tlink_tcon(struct tcon_link *tlink)
+{
+       return (struct cifsTconInfo *)tlink;
+}
+
+static inline void
+cifs_put_tlink(struct tcon_link *tlink)
+{
+       return;
+}
+
+static inline struct tcon_link *
+cifs_get_tlink(struct tcon_link *tlink)
+{
+       return tlink;
+}
+
+/* This function is always expected to succeed */
+static inline struct cifsTconInfo *
+cifs_sb_master_tcon(struct cifs_sb_info *cifs_sb)
+{
+       return cifs_sb->ptcon;
+}
+
 /*
  * This info hangs off the cifsFileInfo structure, pointed to by llist.
  * This is used to track byte stream locks on the file
@@ -350,6 +395,7 @@ struct cifsFileInfo {
        struct file *pfile; /* needed for writepage */
        struct inode *pInode; /* needed for oplock break */
        struct vfsmount *mnt;
+       struct tcon_link *tlink;
        struct mutex lock_mutex;
        struct list_head llist; /* list of byte range locks we have. */
        bool closePend:1;       /* file is marked to close */
@@ -371,6 +417,7 @@ static inline void cifsFileInfo_get(struct cifsFileInfo *cifs_file)
 static inline void cifsFileInfo_put(struct cifsFileInfo *cifs_file)
 {
        if (atomic_dec_and_test(&cifs_file->count)) {
+               cifs_put_tlink(cifs_file->tlink);
                iput(cifs_file->pInode);
                kfree(cifs_file);
        }