fuse: introduce per-instance fuse_dev structure
Allow fuse device clones to refer to be distinguished. This patch just
adds the infrastructure by associating a separate "struct fuse_dev" with
each clone.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index 8373f59..e399383 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -598,6 +598,7 @@
fuse_pqueue_init(&fc->pq);
INIT_LIST_HEAD(&fc->bg_queue);
INIT_LIST_HEAD(&fc->entry);
+ INIT_LIST_HEAD(&fc->devices);
atomic_set(&fc->num_waiting, 0);
fc->max_background = FUSE_DEFAULT_MAX_BACKGROUND;
fc->congestion_threshold = FUSE_DEFAULT_CONGESTION_THRESHOLD;
@@ -945,6 +946,7 @@
static void fuse_free_conn(struct fuse_conn *fc)
{
+ WARN_ON(!list_empty(&fc->devices));
kfree_rcu(fc, rcu);
}
@@ -990,8 +992,41 @@
return 0;
}
+struct fuse_dev *fuse_dev_alloc(struct fuse_conn *fc)
+{
+ struct fuse_dev *fud;
+
+ fud = kzalloc(sizeof(struct fuse_dev), GFP_KERNEL);
+ if (fud) {
+ fud->fc = fuse_conn_get(fc);
+
+ spin_lock(&fc->lock);
+ list_add_tail(&fud->entry, &fc->devices);
+ spin_unlock(&fc->lock);
+ }
+
+ return fud;
+}
+EXPORT_SYMBOL_GPL(fuse_dev_alloc);
+
+void fuse_dev_free(struct fuse_dev *fud)
+{
+ struct fuse_conn *fc = fud->fc;
+
+ if (fc) {
+ spin_lock(&fc->lock);
+ list_del(&fud->entry);
+ spin_unlock(&fc->lock);
+
+ fuse_conn_put(fc);
+ }
+ kfree(fud);
+}
+EXPORT_SYMBOL_GPL(fuse_dev_free);
+
static int fuse_fill_super(struct super_block *sb, void *data, int silent)
{
+ struct fuse_dev *fud;
struct fuse_conn *fc;
struct inode *root;
struct fuse_mount_data d;
@@ -1043,11 +1078,15 @@
fuse_conn_init(fc);
fc->release = fuse_free_conn;
+ fud = fuse_dev_alloc(fc);
+ if (!fud)
+ goto err_put_conn;
+
fc->dev = sb->s_dev;
fc->sb = sb;
err = fuse_bdi_init(fc, sb);
if (err)
- goto err_put_conn;
+ goto err_dev_free;
sb->s_bdi = &fc->bdi;
@@ -1068,7 +1107,7 @@
root = fuse_get_root_inode(sb, d.rootmode);
root_dentry = d_make_root(root);
if (!root_dentry)
- goto err_put_conn;
+ goto err_dev_free;
/* only now - we want root dentry with NULL ->d_op */
sb->s_d_op = &fuse_dentry_operations;
@@ -1094,7 +1133,7 @@
list_add_tail(&fc->entry, &fuse_conn_list);
sb->s_root = root_dentry;
- file->private_data = fuse_conn_get(fc);
+ file->private_data = fud;
mutex_unlock(&fuse_mutex);
/*
* atomic_dec_and_test() in fput() provides the necessary
@@ -1113,6 +1152,8 @@
fuse_request_free(init_req);
err_put_root:
dput(root_dentry);
+ err_dev_free:
+ fuse_dev_free(fud);
err_put_conn:
fuse_bdi_destroy(fc);
fuse_conn_put(fc);