[CRIU] [PATCH 2/2] img: Introduce v1.1 images (v2)
Kuprieiev Ruslan
rkuprieiev at cloudlinux.com
Wed Apr 8 07:00:14 PDT 2015
Acked-by: Ruslan Kuprieiev <rkuprieiev at cloudlinux.com>
On 04/08/2015 04:37 PM, Pavel Emelyanov wrote:
> These images have common magic in front of per-image one. With
> this we have 3 "types" of images -- inventory (head), other
> images, service files. The latter would be stats (not an image,
> just happen to be in PB format) and irmap cache (not an image
> again, just auxiliary thing which is in PB for convenience).
>
> Since inventory file is the first one we read on restore it's
> OK to set the global "new images" flag there. Dump (write) is
> always in new format.
>
> Signed-off-by: Pavel Emelyanov <xemul at parallels.com>
> ---
> image-desc.c | 2 ++
> image.c | 40 +++++++++++++++++++++++++++++++++++++---
> include/image.h | 11 ++++++-----
> include/magic.h | 18 +++++++++++++++++-
> pycriu/images/images.py | 9 +++++++++
> 5 files changed, 71 insertions(+), 9 deletions(-)
>
> diff --git a/image-desc.c b/image-desc.c
> index 4be7551..8d74024 100644
> --- a/image-desc.c
> +++ b/image-desc.c
> @@ -93,11 +93,13 @@ struct cr_fd_desc_tmpl imgset_template[CR_FD_MAX] = {
> [CR_FD_STATS] = {
> .fmt = "stats-%s",
> .magic = STATS_MAGIC,
> + .oflags = O_SERVICE,
> },
>
> [CR_FD_IRMAP_CACHE] = {
> .fmt = "irmap-cache",
> .magic = IRMAP_CACHE_MAGIC,
> + .oflags = O_SERVICE,
> },
>
> [CR_FD_FILE_LOCKS_PID] = {
> diff --git a/image.c b/image.c
> index 1f6f15b..676a40e 100644
> --- a/image.c
> +++ b/image.c
> @@ -14,6 +14,7 @@
>
> bool fdinfo_per_id = false;
> bool ns_per_id = false;
> +bool img_common_magic = false;
> TaskKobjIdsEntry *root_ids;
> u32 root_cg_set;
>
> @@ -50,10 +51,19 @@ int check_img_inventory(void)
> root_cg_set = he->root_cg_set;
> }
>
> - if (he->img_version != CRTOOLS_IMAGES_V1) {
> + switch (he->img_version) {
> + case CRTOOLS_IMAGES_V1:
> + /* good old images. OK */
> + break;
> + case CRTOOLS_IMAGES_V1_1:
> + /* newer images with extra magic in the head */
> + img_common_magic = true;
> + break;
> + default:
> pr_err("Not supported images version %u\n", he->img_version);
> goto out_err;
> }
> +
> ret = 0;
>
> out_err:
> @@ -78,7 +88,8 @@ int write_img_inventory(void)
> if (!img)
> return -1;
>
> - he.img_version = CRTOOLS_IMAGES_V1;
> + img_common_magic = true;
> + he.img_version = CRTOOLS_IMAGES_V1_1;
> he.fdinfo_per_id = true;
> he.has_fdinfo_per_id = true;
> he.ns_per_id = true;
> @@ -238,6 +249,11 @@ struct cr_img *open_image_at(int dfd, int type, unsigned long flags, ...)
> return do_open_image(img, dfd, type, oflags, path);
> }
>
> +static inline u32 head_magic(int oflags)
> +{
> + return oflags & O_SERVICE ? IMG_SERVICE_MAGIC : IMG_COMMON_MAGIC;
> +}
> +
> static int img_check_magic(struct cr_img *img, int oflags, int type, char *path)
> {
> u32 magic;
> @@ -245,6 +261,16 @@ static int img_check_magic(struct cr_img *img, int oflags, int type, char *path)
> if (read_img(img, &magic) < 0)
> return -1;
>
> + if (img_common_magic && (type != CR_FD_INVENTORY)) {
> + if (magic != head_magic(oflags)) {
> + pr_err("Head magic doesn't match for %s\n", path);
> + return -1;
> + }
> +
> + if (read_img(img, &magic) < 0)
> + return -1;
> + }
> +
> if (magic != imgset_template[type].magic) {
> pr_err("Magic doesn't match for %s\n", path);
> return -1;
> @@ -255,6 +281,14 @@ static int img_check_magic(struct cr_img *img, int oflags, int type, char *path)
>
> static int img_write_magic(struct cr_img *img, int oflags, int type)
> {
> + if (img_common_magic && (type != CR_FD_INVENTORY)) {
> + u32 cmagic;
> +
> + cmagic = head_magic(oflags);
> + if (write_img(img, &cmagic))
> + return -1;
> + }
> +
> return write_img(img, &imgset_template[type].magic);
> }
>
> @@ -262,7 +296,7 @@ static struct cr_img *do_open_image(struct cr_img *img, int dfd, int type, unsig
> {
> int ret, flags;
>
> - flags = oflags & ~(O_NOBUF);
> + flags = oflags & ~(O_NOBUF | O_SERVICE);
>
> ret = openat(dfd, path, flags, CR_FD_PERM);
> if (ret < 0) {
> diff --git a/include/image.h b/include/image.h
> index 9ec0238..55e63dd 100644
> --- a/include/image.h
> +++ b/include/image.h
> @@ -116,12 +116,13 @@
>
> extern bool fdinfo_per_id;
> extern bool ns_per_id;
> +extern bool img_common_magic;
>
> -#define O_NOBUF (O_DIRECT)
> -
> -#define O_DUMP (O_WRONLY | O_CREAT | O_TRUNC)
> -#define O_SHOW (O_RDONLY | O_NOBUF)
> -#define O_RSTR (O_RDONLY)
> +#define O_NOBUF (O_DIRECT)
> +#define O_SERVICE (O_DIRECTORY)
> +#define O_DUMP (O_WRONLY | O_CREAT | O_TRUNC)
> +#define O_SHOW (O_RDONLY | O_NOBUF)
> +#define O_RSTR (O_RDONLY)
>
> struct cr_img {
> union {
> diff --git a/include/magic.h b/include/magic.h
> index d9af16c..57dd29b 100644
> --- a/include/magic.h
> +++ b/include/magic.h
> @@ -6,6 +6,11 @@
> */
>
> #define CRTOOLS_IMAGES_V1 1
> +/*
> + * v1.1 has common magic in the head of each image file,
> + * except for inventory
> + */
> +#define CRTOOLS_IMAGES_V1_1 2
>
> /*
> * Raw images are images in which data is stored in some
> @@ -15,13 +20,20 @@
> #define RAW_IMAGE_MAGIC 0x0
>
> /*
> + * Images have the IMG_COMMON_MAGIC in the head. Service files
> + * such as stats and irmap-cache have the IMG_SERVICE_MAGIC.
> + */
> +
> +#define IMG_COMMON_MAGIC 0x54564319 /* Sarov (a.k.a. Arzamas-16) */
> +#define IMG_SERVICE_MAGIC 0x55105940 /* Zlatoust */
> +
> +/*
> * The magic-s below correspond to coordinates
> * of various Russian towns in the NNNNEEEE form.
> */
>
> #define INVENTORY_MAGIC 0x58313116 /* Veliky Novgorod */
> #define PSTREE_MAGIC 0x50273030 /* Kyiv */
> -#define STATS_MAGIC 0x57093306 /* Ostashkov */
> #define FDINFO_MAGIC 0x56213732 /* Dmitrov */
> #define PAGEMAP_MAGIC 0x56084025 /* Vladimir */
> #define SHMEM_PAGEMAP_MAGIC PAGEMAP_MAGIC
> @@ -86,6 +98,10 @@
> #define PAGES_OLD_MAGIC PAGEMAP_MAGIC
> #define SHM_PAGES_OLD_MAGIC PAGEMAP_MAGIC
>
> +/*
> + * These are special files, not exactly images
> + */
> +#define STATS_MAGIC 0x57093306 /* Ostashkov */
> #define IRMAP_CACHE_MAGIC 0x57004059 /* Ivanovo */
>
> #endif /* __CR_MAGIC_H__ */
> diff --git a/pycriu/images/images.py b/pycriu/images/images.py
> index f0bfe84..5dde50c 100644
> --- a/pycriu/images/images.py
> +++ b/pycriu/images/images.py
> @@ -287,6 +287,9 @@ def load(f, pretty = False):
>
> img_magic, = struct.unpack('i', f.read(4))
>
> + if img_magic in (magic.by_name['IMG_COMMON'], magic.by_name['IMG_SERVICE']):
> + img_magic, = struct.unpack('i', f.read(4))
> +
> try:
> m = magic.by_val[img_magic]
> except:
> @@ -320,6 +323,12 @@ def dump(img, f):
> m = img['magic']
> magic_val = magic.by_name[img['magic']]
>
> + if m != 'INVENTORY':
> + if m in ('STATS', 'IRMAP_CACHE'):
> + f.write(struct.pack('i', magic.by_name['IMG_COMMON']))
> + else:
> + f.write(struct.pack('i', magic.by_name['IMG_SERVICE']))
> +
> f.write(struct.pack('i', magic_val))
>
> try:
More information about the CRIU
mailing list