From: Stefan Hajnoczi <stefanha@xxxxxxxxxx>
A struct dax_device instance is a prerequisite for the DAX filesystem
APIs. Let virtio_fs associate a dax_device with a fuse_conn. Classic
FUSE and CUSE set the pointer to NULL, disabling DAX.
Signed-off-by: Stefan Hajnoczi <stefanha@xxxxxxxxxx>
---
fs/fuse/cuse.c | 3 ++-
fs/fuse/fuse_i.h | 9 ++++++++-
fs/fuse/inode.c | 9 ++++++---
fs/fuse/virtio_fs.c | 5 +++--
4 files changed, 19 insertions(+), 7 deletions(-)
diff --git a/fs/fuse/cuse.c b/fs/fuse/cuse.c
index 04727540bdbb..0f9e3c93b056 100644
--- a/fs/fuse/cuse.c
+++ b/fs/fuse/cuse.c
@@ -504,7 +504,8 @@ static int cuse_channel_open(struct inode *inode, struct file *file)
* Limit the cuse channel to requests that can
* be represented in file->f_cred->user_ns.
*/
- fuse_conn_init(&cc->fc, file->f_cred->user_ns, &fuse_dev_fiq_ops, NULL);
+ fuse_conn_init(&cc->fc, file->f_cred->user_ns, NULL, &fuse_dev_fiq_ops,
+ NULL);
fud = fuse_dev_alloc_install(&cc->fc);
if (!fud) {
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index 25a6da6ee8c3..ecd9dbc3312e 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -77,6 +77,9 @@ struct fuse_mount_data {
unsigned max_read;
unsigned blksize;
+ /* DAX device, may be NULL */
+ struct dax_device *dax_dev;
+
/* fuse input queue operations */
const struct fuse_iqueue_ops *fiq_ops;
@@ -831,6 +834,9 @@ struct fuse_conn {
/** List of device instances belonging to this connection */
struct list_head devices;
+
+ /** DAX device, non-NULL if DAX is supported */
+ struct dax_device *dax_dev;
};
static inline struct fuse_conn *get_fuse_conn_super(struct super_block *sb)
@@ -1061,7 +1067,8 @@ struct fuse_conn *fuse_conn_get(struct fuse_conn *fc);
* Initialize fuse_conn
*/
void fuse_conn_init(struct fuse_conn *fc, struct user_namespace *user_ns,
- const struct fuse_iqueue_ops *fiq_ops, void *fiq_priv);
+ struct dax_device *dax_dev,
+ const struct fuse_iqueue_ops *fiq_ops, void *fiq_priv);
/**
* Release reference to fuse_conn
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index 16bcf0f95979..6d9258a4091a 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -591,7 +591,8 @@ static void fuse_pqueue_init(struct fuse_pqueue *fpq)
}
void fuse_conn_init(struct fuse_conn *fc, struct user_namespace *user_ns,
- const struct fuse_iqueue_ops *fiq_ops, void *fiq_priv)
+ struct dax_device *dax_dev,
+ const struct fuse_iqueue_ops *fiq_ops, void *fiq_priv)
{
memset(fc, 0, sizeof(*fc));
spin_lock_init(&fc->lock);
@@ -616,6 +617,7 @@ void fuse_conn_init(struct fuse_conn *fc, struct user_namespace *user_ns,
atomic64_set(&fc->attr_version, 1);
get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key));
fc->pid_ns = get_pid_ns(task_active_pid_ns(current));
+ fc->dax_dev = dax_dev;
fc->user_ns = get_user_ns(user_ns);
fc->max_pages = FUSE_DEFAULT_MAX_PAGES_PER_REQ;
}
@@ -1132,8 +1134,8 @@ int fuse_fill_super_common(struct super_block *sb,
err = -ENOMEM;
if (!fc)
goto err;
- fuse_conn_init(fc, sb->s_user_ns, mount_data->fiq_ops,
- mount_data->fiq_priv);
+ fuse_conn_init(fc, sb->s_user_ns, mount_data->dax_dev,
+ mount_data->fiq_ops, mount_data->fiq_priv);
fc->release = fuse_free_conn;
}
@@ -1237,6 +1239,7 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent)
goto err_fput;
__set_bit(FR_BACKGROUND, &init_req->flags);
+ d.dax_dev = NULL;
d.fiq_ops = &fuse_dev_fiq_ops;
d.fiq_priv = NULL;
d.fudptr = &file->private_data;
diff --git a/fs/fuse/virtio_fs.c b/fs/fuse/virtio_fs.c
index ce1de9acde84..706b27e0502a 100644
--- a/fs/fuse/virtio_fs.c
+++ b/fs/fuse/virtio_fs.c
@@ -986,8 +986,9 @@ static struct dentry *virtio_fs_mount(struct file_system_type *fs_type,
fc = kzalloc(sizeof(struct fuse_conn), GFP_KERNEL);
if (!fc)
return ERR_PTR(-ENOMEM);
- fuse_conn_init(fc, get_user_ns(current_user_ns()), &virtio_fs_fiq_ops,
- fs);
+ d.dax_dev = NULL;
+ fuse_conn_init(fc, get_user_ns(current_user_ns()), d.dax_dev,
+ &virtio_fs_fiq_ops, fs);
fc->release = fuse_free_conn;
s = sget(fs_type, virtio_fs_test_super, virtio_fs_set_super, flags, fc);
--
2.20.1
