fuse: split fuse_mount off of fuse_conn

We want to allow submounts for the same fuse_conn, but with different
superblocks so that each of the submounts has its own device ID.  To do
so, we need to split all mount-specific information off of fuse_conn
into a new fuse_mount structure, so that multiple mounts can share a
single fuse_conn.

We need to take care only to perform connection-level actions once (i.e.
when the fuse_conn and thus the first fuse_mount are established, or
when the last fuse_mount and thus the fuse_conn are destroyed).  For
example, fuse_sb_destroy() must invoke fuse_send_destroy() until the
last superblock is released.

To do so, we keep track of which fuse_mount is the root mount and
perform all fuse_conn-level actions only when this fuse_mount is
involved.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

1 files changed, 5 insertions, 5 deletions

diff --git a/fs/fuse/readdir.c b/fs/fuse/readdir.c
index 90e3f01bd796..3b5e91045871 100644
--- a/fs/fuse/readdir.c
+++ b/fs/fuse/readdir.c
@@ -252,7 +252,7 @@ retry:
 static void fuse_force_forget(struct file *file, u64 nodeid)
 {
 	struct inode *inode = file_inode(file);
-	struct fuse_conn *fc = get_fuse_conn(inode);
+	struct fuse_mount *fm = get_fuse_mount(inode);
 	struct fuse_forget_in inarg;
 	FUSE_ARGS(args);
 
@@ -266,7 +266,7 @@ static void fuse_force_forget(struct file *file, u64 nodeid)
 	args.force = true;
 	args.noreply = true;
 
-	fuse_simple_request(fc, &args);
+	fuse_simple_request(fm, &args);
 	/* ignore errors */
 }
 
@@ -320,7 +320,7 @@ static int fuse_readdir_uncached(struct file *file, struct dir_context *ctx)
 	ssize_t res;
 	struct page *page;
 	struct inode *inode = file_inode(file);
-	struct fuse_conn *fc = get_fuse_conn(inode);
+	struct fuse_mount *fm = get_fuse_mount(inode);
 	struct fuse_io_args ia = {};
 	struct fuse_args_pages *ap = &ia.ap;
 	struct fuse_page_desc desc = { .length = PAGE_SIZE };
@@ -337,7 +337,7 @@ static int fuse_readdir_uncached(struct file *file, struct dir_context *ctx)
 	ap->pages = &page;
 	ap->descs = &desc;
 	if (plus) {
-		attr_version = fuse_get_attr_version(fc);
+		attr_version = fuse_get_attr_version(fm->fc);
 		fuse_read_args_fill(&ia, file, ctx->pos, PAGE_SIZE,
 				    FUSE_READDIRPLUS);
 	} else {
@@ -345,7 +345,7 @@ static int fuse_readdir_uncached(struct file *file, struct dir_context *ctx)
 				    FUSE_READDIR);
 	}
 	locked = fuse_lock_inode(inode);
-	res = fuse_simple_request(fc, &ap->args);
+	res = fuse_simple_request(fm, &ap->args);
 	fuse_unlock_inode(inode, locked);
 	if (res >= 0) {
 		if (!res) {