fuse: add reference counting to fuse_file

Make lifetime of 'struct fuse_file' independent from 'struct file' by adding a
reference counter and destructor.

This will enable asynchronous page writeback, where it cannot be guaranteed,
that the file is not released while a request with this file handle is being
served.

The actual RELEASE request is only sent when there are no more references to
the fuse_file.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 7 insertions, 7 deletions

diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index bd5a772d8ccf..35e5cabb3b8c 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -288,12 +288,11 @@ static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry,
 static void fuse_sync_release(struct fuse_conn *fc, struct fuse_file *ff,
                               u64 nodeid, int flags)
 {
-        struct fuse_req *req;
-
-        req = fuse_release_fill(ff, nodeid, flags, FUSE_RELEASE);
-        req->force = 1;
-        request_send(fc, req);
-        fuse_put_request(fc, req);
+        fuse_release_fill(ff, nodeid, flags, FUSE_RELEASE);
+        ff->reserved_req->force = 1;
+        request_send(fc, ff->reserved_req);
+        fuse_put_request(fc, ff->reserved_req);
+        kfree(ff);
 }
 
 /*
@@ -859,6 +858,7 @@ static int fuse_readdir(struct file *file, void *dstbuf, filldir_t filldir)
         struct page *page;
         struct inode *inode = file->f_path.dentry->d_inode;
         struct fuse_conn *fc = get_fuse_conn(inode);
+        struct fuse_file *ff = file->private_data;
         struct fuse_req *req;
 
         if (is_bad_inode(inode))
@@ -875,7 +875,7 @@ static int fuse_readdir(struct file *file, void *dstbuf, filldir_t filldir)
         }
         req->num_pages = 1;
         req->pages[0] = page;
-        fuse_read_fill(req, file, inode, file->f_pos, PAGE_SIZE, FUSE_READDIR);
+        fuse_read_fill(req, ff, inode, file->f_pos, PAGE_SIZE, FUSE_READDIR);
         request_send(fc, req);
         nbytes = req->out.args[0].size;
         err = req->out.h.error;