[PATCH v2 12/13] ceph/file: allow idmapped atomic_open inode op

[Alexander Mikhalitsyn <aleksandr.mikhalitsyn@xxxxxxxxxxxxx>]

From: Christian Brauner <christian.brauner@xxxxxxxxxx>

Enable ceph_atomic_open() to handle idmapped mounts. This is just a
matter of passing down the mount's idmapping.

Cc: Jeff Layton <jlayton@xxxxxxxxxx>
Cc: Ilya Dryomov <idryomov@xxxxxxxxx>
Cc: ceph-devel@xxxxxxxxxxxxxxx
Signed-off-by: Christian Brauner <christian.brauner@xxxxxxxxxx>
Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@xxxxxxxxxxxxx>
---
v2:
	- rebased, see also 5fadbd9929 ("ceph: rely on vfs for setgid stripping")
---
 fs/ceph/file.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index f4d8bf7dec88..f00bfda4b1d2 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -654,7 +654,9 @@ static int ceph_finish_async_create(struct inode *dir, struct dentry *dentry,
 	in.truncate_seq = cpu_to_le32(1);
 	in.truncate_size = cpu_to_le64(-1ULL);
 	in.xattr_version = cpu_to_le64(1);
-	in.uid = cpu_to_le32(from_kuid(&init_user_ns, current_fsuid()));
+	in.uid = cpu_to_le32(from_kuid(&init_user_ns,
+				       mapped_fsuid(req->r_mnt_idmap,
+						    &init_user_ns)));
 	if (dir->i_mode & S_ISGID) {
 		in.gid = cpu_to_le32(from_kgid(&init_user_ns, dir->i_gid));
 
@@ -662,7 +664,9 @@ static int ceph_finish_async_create(struct inode *dir, struct dentry *dentry,
 		if (S_ISDIR(mode))
 			mode |= S_ISGID;
 	} else {
-		in.gid = cpu_to_le32(from_kgid(&init_user_ns, current_fsgid()));
+		in.gid = cpu_to_le32(from_kgid(&init_user_ns,
+				     mapped_fsgid(req->r_mnt_idmap,
+						  &init_user_ns)));
 	}
 	in.mode = cpu_to_le32((u32)mode);
 
@@ -731,6 +735,7 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
 		     struct file *file, unsigned flags, umode_t mode)
 {
 	struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
+	struct mnt_idmap *idmap = file_mnt_idmap(file);
 	struct ceph_mds_client *mdsc = fsc->mdsc;
 	struct ceph_mds_request *req;
 	struct dentry *dn;
@@ -786,6 +791,7 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
 		mask |= CEPH_CAP_XATTR_SHARED;
 	req->r_args.open.mask = cpu_to_le32(mask);
 	req->r_parent = dir;
+	req->r_mnt_idmap = idmap;
 	ihold(dir);
 
 	if (flags & O_CREAT) {
-- 
2.34.1