libmount: (mount) support --move by new kernel API

* support --move in new mount implementation

* remember errno from mount related failed syscalls

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/libmount/src/hook_mount.c b/libmount/src/hook_mount.c
index d00f9bcea59d11c8b22ca68fcd790f878c54a747..4c60d267d47626c343e1b672be7973f4581aaa6a 100644 (file)
--- a/libmount/src/hook_mount.c
+++ b/libmount/src/hook_mount.c
@@ -111,7 +111,6 @@ static int set_vfs_flags(int fd, struct libmnt_context *cxt, int recursive)
        struct mount_attr attr = { .attr_clr = 0 };
        unsigned int callflags = AT_EMPTY_PATH;
        uint64_t mask = 0;
-       int rc;
 
        ol= mnt_context_get_optlist(cxt);
        if (!ol)
@@ -123,9 +122,10 @@ static int set_vfs_flags(int fd, struct libmnt_context *cxt, int recursive)
                callflags |= AT_RECURSIVE;
 
        DBG(HOOK, ul_debug(" mount_setattr(set=0x%" PRIx64")", mask));
-       rc = mount_setattr(fd, "", callflags, &attr, sizeof(attr));
-       if (rc)
+       if (mount_setattr(fd, "", callflags, &attr, sizeof(attr))) {
+               cxt->syscall_status = -errno;
                return -errno;
+       }
 
        return 0;
 }
@@ -158,8 +158,10 @@ static int hook_attach_target(struct libmnt_context *cxt,
                return -EINVAL;
 
        DBG(HOOK, ul_debugobj(hs, " move_mount(to=%s)", target));
-       if (move_mount(api->fd_tree, "", AT_FDCWD, target, MOVE_MOUNT_F_EMPTY_PATH))
+       if (move_mount(api->fd_tree, "", AT_FDCWD, target, MOVE_MOUNT_F_EMPTY_PATH)) {
+               cxt->syscall_status = -errno;
                return -errno;
+       }
 
        return 0;
 }
@@ -270,7 +272,7 @@ static int hook_prepare(struct libmnt_context *cxt,
                DBG(HOOK, ul_debugobj(hs, " prepare move"));
                tree_path = src;
                next_stage = MNT_STAGE_MOUNT_POST;
-               /*next_hook = hook_move;*/
+               next_hook = hook_attach_target;
 
        } else if (mnt_context_propagation_only(cxt)) {
                DBG(HOOK, ul_debugobj(hs, " prepare propagation change"));
@@ -289,12 +291,20 @@ static int hook_prepare(struct libmnt_context *cxt,
                if (!type)
                        return -EINVAL;
 
+               if (mnt_context_is_fake(cxt))
+                       goto fake;
+
                DBG(HOOK, ul_debugobj(hs, "fsopen(%s)", type));
                api->fd_fs = fsopen(type, FSOPEN_CLOEXEC);
-               if (api->fd_fs < 0)
+               if (api->fd_fs < 0) {
+                       cxt->syscall_status = -errno;
                        goto nothing;
+               }
        }
 
+       if (mnt_context_is_fake(cxt))
+               goto fake;
+
        if (api->fd_fs == -1) {
                if (!tree_path) {
                        DBG(HOOK, ul_debugobj(hs, "tree path undefined"));
@@ -303,8 +313,10 @@ static int hook_prepare(struct libmnt_context *cxt,
                DBG(HOOK, ul_debugobj(hs, "open_tree(path=%s, flags=0x%lx)",
                                        tree_path, open_flags));
                api->fd_tree = open_tree(AT_FDCWD, tree_path, open_flags);
-               if (api->fd_tree <= 0)
+               if (api->fd_tree <= 0) {
+                       cxt->syscall_status = -errno;
                        goto nothing;
+               }
        }
 
        return mnt_context_append_hook(cxt, hs, next_stage, NULL, next_hook);
@@ -313,6 +325,10 @@ nothing:
        DBG(HOOK, ul_debugobj(hs, " open fs/tree failed [errno=%d %m]", errno));
        free_hookset_data(cxt, hs);
        return 0;
+fake:
+       DBG(CXT, ul_debugobj(cxt, "  FAKE (-f)"));
+       cxt->syscall_status = 0;
+       return 0;
 }
 
 const struct libmnt_hookset hookset_mount =