[CRIU] [PATCH v4 05/17] spfs: delayed mounts facility introduced

[Pavel Emelyanov]

On 05/20/2016 02:37 PM, Stanislav Kinsburskiy wrote:
> This facility allows to migated such mounts, like NFS, by replacing the actual
> mount by FUSE (spfs) mount.
> Spfs allows to create and open files, required for restore, and then (by
> switching spfs to "Stub" mode) to block any incomming file system requests.
> This facility does spfs mount via spfs manager, which is then instructed, how
> to mount the actual file system.
> Spfs manager is also responsible for replacing of spfs mount and opened files
> by the actual one (and actual files) once actual mount point is remounted.

This patch launches some other binary. Have you sent the spfs implementation
itself earlier?

one more comment inline.

> Signed-off-by: Stanislav Kinsburskiy <skinsbursky at virtuozzo.com>
> ---
>  criu/Makefile.crtools |    1 
>  criu/include/spfs.h   |   13 +
>  criu/spfs.c           |  451 +++++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 465 insertions(+)
>  create mode 100644 criu/include/spfs.h
>  create mode 100644 criu/spfs.c
> 
> diff --git a/criu/Makefile.crtools b/criu/Makefile.crtools
> index 657b08e..3d246f1 100644
> --- a/criu/Makefile.crtools
> +++ b/criu/Makefile.crtools
> @@ -78,6 +78,7 @@ obj-y			+= util.o
>  obj-y			+= uts_ns.o
>  obj-y			+= autofs.o
>  obj-y			+= uffd.o
> +obj-y			+= spfs.o
>  
>  ifeq ($(VDSO),y)
>  obj-y			+= pie-util-vdso.o
> diff --git a/criu/include/spfs.h b/criu/include/spfs.h
> new file mode 100644
> index 0000000..395572c
> --- /dev/null
> +++ b/criu/include/spfs.h
> @@ -0,0 +1,13 @@
> +#ifndef __CR_SPFS_H__
> +#define __CR_SPFS_H__
> +
> +int spfs_set_env(void);
> +
> +struct mount_info;
> +int spfs_mount(struct mount_info *mi, const char *source,
> +	      const char *filesystemtype, unsigned long mountflags);
> +
> +struct reg_file_info;
> +int spfs_create_file(int ns_root_id, const struct reg_file_info *rfi);

Write code comments before each declaration explaining what each function does
and what for.

> +#endif