1 files changed, 68 insertions, 0 deletions
diff --git a/weed/mount/weedfs_forget.go b/weed/mount/weedfs_forget.go
new file mode 100644
index 000000000..62946b216
--- /dev/null
+++ b/weed/mount/weedfs_forget.go
@@ -0,0 +1,68 @@
+package mount
+
+import (
+	"context"
+	"github.com/chrislusf/seaweedfs/weed/util"
+)
+
+// Forget is called when the kernel discards entries from its
+// dentry cache. This happens on unmount, and when the kernel
+// is short on memory. Since it is not guaranteed to occur at
+// any moment, and since there is no return value, Forget
+// should not do I/O, as there is no channel to report back
+// I/O errors.
+// from https://github.com/libfuse/libfuse/blob/master/include/fuse_lowlevel.h
+/**
+ * Forget about an inode
+ *
+ * This function is called when the kernel removes an inode
+ * from its internal caches.
+ *
+ * The inode's lookup count increases by one for every call to
+ * fuse_reply_entry and fuse_reply_create. The nlookup parameter
+ * indicates by how much the lookup count should be decreased.
+ *
+ * Inodes with a non-zero lookup count may receive request from
+ * the kernel even after calls to unlink, rmdir or (when
+ * overwriting an existing file) rename. Filesystems must handle
+ * such requests properly and it is recommended to defer removal
+ * of the inode until the lookup count reaches zero. Calls to
+ * unlink, rmdir or rename will be followed closely by forget
+ * unless the file or directory is open, in which case the
+ * kernel issues forget only after the release or releasedir
+ * calls.
+ *
+ * Note that if a file system will be exported over NFS the
+ * inodes lifetime must extend even beyond forget. See the
+ * generation field in struct fuse_entry_param above.
+ *
+ * On unmount the lookup count for all inodes implicitly drops
+ * to zero. It is not guaranteed that the file system will
+ * receive corresponding forget messages for the affected
+ * inodes.
+ *
+ * Valid replies:
+ *   fuse_reply_none
+ *
+ * @param req request handle
+ * @param ino the inode number
+ * @param nlookup the number of lookups to forget
+ */
+/*
+https://libfuse.github.io/doxygen/include_2fuse__lowlevel_8h.html
+
+int fuse_reply_entry	(	fuse_req_t 	req,
+const struct fuse_entry_param * 	e
+)
+Reply with a directory entry
+
+Possible requests: lookup, mknod, mkdir, symlink, link
+
+Side effects: increments the lookup count on success
+
+*/
+func (wfs *WFS) Forget(nodeid, nlookup uint64) {
+	wfs.inodeToPath.Forget(nodeid, nlookup, func(dir util.FullPath) {
+		wfs.metaCache.DeleteFolderChildren(context.Background(), dir)
+	})
+}