[RFC PATCH 30/68] vfs: Convert fusectl to use the new mount API

From: David Howells
Date: Wed Mar 27 2019 - 19:44:25 EST


Convert the fusectl filesystem to the new internal mount API as the old
one will be obsoleted and removed. This allows greater flexibility in
communication of mount parameters between userspace, the VFS and the
filesystem.

See Documentation/filesystems/mount_api.txt for more information.

Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
cc: Miklos Szeredi <miklos@xxxxxxxxxx>
cc: linux-fsdevel@xxxxxxxxxxxxxxx
---

fs/fuse/control.c | 20 +++++++++++++++-----
1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/fs/fuse/control.c b/fs/fuse/control.c
index fe80bea4ad89..14ce1e47f980 100644
--- a/fs/fuse/control.c
+++ b/fs/fuse/control.c
@@ -10,6 +10,7 @@

#include <linux/init.h>
#include <linux/module.h>
+#include <linux/fs_context.h>

#define FUSE_CTL_SUPER_MAGIC 0x65735543

@@ -317,7 +318,7 @@ void fuse_ctl_remove_conn(struct fuse_conn *fc)
drop_nlink(d_inode(fuse_control_sb->s_root));
}

-static int fuse_ctl_fill_super(struct super_block *sb, void *data, int silent)
+static int fuse_ctl_fill_super(struct super_block *sb, struct fs_context *fctx)
{
static const struct tree_descr empty_descr = {""};
struct fuse_conn *fc;
@@ -343,10 +344,19 @@ static int fuse_ctl_fill_super(struct super_block *sb, void *data, int silent)
return 0;
}

-static struct dentry *fuse_ctl_mount(struct file_system_type *fs_type,
- int flags, const char *dev_name, void *raw_data)
+static int fuse_ctl_get_tree(struct fs_context *fc)
{
- return mount_single(fs_type, flags, raw_data, fuse_ctl_fill_super);
+ return vfs_get_super(fc, vfs_get_single_super, fuse_ctl_fill_super);
+}
+
+static const struct fs_context_operations fuse_ctl_context_ops = {
+ .get_tree = fuse_ctl_get_tree,
+};
+
+static int fuse_ctl_init_fs_context(struct fs_context *fc)
+{
+ fc->ops = &fuse_ctl_context_ops;
+ return 0;
}

static void fuse_ctl_kill_sb(struct super_block *sb)
@@ -365,7 +375,7 @@ static void fuse_ctl_kill_sb(struct super_block *sb)
static struct file_system_type fuse_ctl_fs_type = {
.owner = THIS_MODULE,
.name = "fusectl",
- .mount = fuse_ctl_mount,
+ .init_fs_context = fuse_ctl_init_fs_context,
.kill_sb = fuse_ctl_kill_sb,
};
MODULE_ALIAS_FS("fusectl");