search for: virtio_fs_get_tree

...vices. + * and drain one more time and free fuse devices. Freeing fuse + * devices will drop their reference on fuse_conn and that in + * turn will drop its reference on virtio_fs object. */ virtio_fs_stop_all_queues(vfs); virtio_fs_drain_all_queues(vfs); @@ -1060,6 +1088,10 @@ static int virtio_fs_get_tree(struct fs_context *fsc) struct fuse_conn *fc; int err; + /* This gets a reference on virtio_fs object. This ptr gets installed + * in fc->iq->priv. Once fuse_conn is going away, it calls ->put() + * to drop the reference to this object. + */ fs = virtio_fs_find_instance(fsc->...

On Thu, Sep 05, 2019 at 03:48:56PM -0400, Vivek Goyal wrote: > This object is used both by fuse_connection as well virt device. So make > this object reference counted and that makes it easy to define life cycle > of the object. > > Now deivce can be removed while filesystem is still mounted. This will > cleanup all the virtqueues but virtio_fs object will still be around and

On Thu, Sep 05, 2019 at 03:48:56PM -0400, Vivek Goyal wrote: > This object is used both by fuse_connection as well virt device. So make > this object reference counted and that makes it easy to define life cycle > of the object. > > Now deivce can be removed while filesystem is still mounted. This will > cleanup all the virtqueues but virtio_fs object will still be around and

...vices. + * and drain one more time and free fuse devices. Freeing fuse + * devices will drop their reference on fuse_conn and that in + * turn will drop its reference on virtio_fs object. */ virtio_fs_stop_all_queues(vfs); virtio_fs_drain_all_queues(vfs); @@ -1060,6 +1088,10 @@ static int virtio_fs_get_tree(struct fs_ struct fuse_conn *fc; int err; + /* This gets a reference on virtio_fs object. This ptr gets installed + * in fc->iq->priv. Once fuse_conn is going away, it calls ->put() + * to drop the reference to this object. + */ fs = virtio_fs_find_instance(fsc->source); if...

On Thu, Sep 05, 2019 at 03:48:57PM -0400, Vivek Goyal wrote: > It is possible that a mount is in progress and device is being removed at > the same time. Use virtio_fs_mutex to avoid races. > > This also takes care of bunch of races and removes some TODO items. > > Signed-off-by: Vivek Goyal <vgoyal at redhat.com> > --- > fs/fuse/virtio_fs.c | 32

On Thu, Sep 05, 2019 at 03:48:57PM -0400, Vivek Goyal wrote: > It is possible that a mount is in progress and device is being removed at > the same time. Use virtio_fs_mutex to avoid races. > > This also takes care of bunch of races and removes some TODO items. > > Signed-off-by: Vivek Goyal <vgoyal at redhat.com> > --- > fs/fuse/virtio_fs.c | 32

...req); + mutex_unlock(&virtio_fs_mutex); return 0; err_free_init_req: @@ -1027,6 +1036,7 @@ static int virtio_fs_fill_super(struct super_block *sb) err_free_fuse_devs: virtio_fs_free_devs(fs); err: + mutex_unlock(&virtio_fs_mutex); return err; } @@ -1100,7 +1110,9 @@ static int virtio_fs_get_tree(struct fs_context *fsc) fc = kzalloc(sizeof(struct fuse_conn), GFP_KERNEL); if (!fc) { + mutex_lock(&virtio_fs_mutex); virtiofs_put(fs); + mutex_unlock(&virtio_fs_mutex); return -ENOMEM; } -- 2.20.1

...ueues(fs); fuse_send_init(fc, init_req); + mutex_unlock(&virtio_fs_mutex); return 0; err_free_init_req: @@ -1027,6 +1036,7 @@ err_free_init_req: err_free_fuse_devs: virtio_fs_free_devs(fs); err: + mutex_unlock(&virtio_fs_mutex); return err; } @@ -1100,7 +1110,9 @@ static int virtio_fs_get_tree(struct fs_ fc = kzalloc(sizeof(struct fuse_conn), GFP_KERNEL); if (!fc) { + mutex_lock(&virtio_fs_mutex); virtio_fs_put(fs); + mutex_unlock(&virtio_fs_mutex); return -ENOMEM; }

Hi, Michael Tsirkin pointed out issues w.r.t various locking related TODO items and races w.r.t device removal. In this first round of cleanups, I have taken care of most pressing issues. These patches apply on top of following. git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse.git#virtiofs-v4 I have tested these patches with mount/umount and device removal using qemu monitor. For

...; + > +static int virtio_fs_set_super(struct super_block *sb, > + struct fs_context *fsc) > +{ > + int err; > + > + err = get_anon_bdev(&sb->s_dev); > + if (!err) > + fuse_conn_get(fsc->s_fs_info); > + > + return err; > +} > + > +static int virtio_fs_get_tree(struct fs_context *fsc) > +{ > + struct virtio_fs *fs; > + struct super_block *sb; > + struct fuse_conn *fc; > + int err; > + > + /* This gets a reference on virtio_fs object. This ptr gets installed > + * in fc->iq->priv. Once fuse_conn is going away, it calls ->p...

...; + > +static int virtio_fs_set_super(struct super_block *sb, > + struct fs_context *fsc) > +{ > + int err; > + > + err = get_anon_bdev(&sb->s_dev); > + if (!err) > + fuse_conn_get(fsc->s_fs_info); > + > + return err; > +} > + > +static int virtio_fs_get_tree(struct fs_context *fsc) > +{ > + struct virtio_fs *fs; > + struct super_block *sb; > + struct fuse_conn *fc; > + int err; > + > + fs = virtio_fs_find_instance(fsc->source); > + if (!fs) { > + pr_info("virtio-fs: tag <%s> not found\n", fsc->source);...

...; + > +static int virtio_fs_set_super(struct super_block *sb, > + struct fs_context *fsc) > +{ > + int err; > + > + err = get_anon_bdev(&sb->s_dev); > + if (!err) > + fuse_conn_get(fsc->s_fs_info); > + > + return err; > +} > + > +static int virtio_fs_get_tree(struct fs_context *fsc) > +{ > + struct virtio_fs *fs; > + struct super_block *sb; > + struct fuse_conn *fc; > + int err; > + > + fs = virtio_fs_find_instance(fsc->source); > + if (!fs) { > + pr_info("virtio-fs: tag <%s> not found\n", fsc->source);...