[PATCH 21/30] cr: deal with pid/pidns
Alexey Dobriyan
adobriyan at gmail.com
Thu Apr 9 19:38:38 PDT 2009
C/R struct pid and struct pid_namespace.
Userspace should see same pids as before.
->last_pid is visible though /proc/loadavg, so it needs to be dumped too, sigh.
FIXME: restoration of pidns is recursive.
Signed-off-by: Alexey Dobriyan <adobriyan at gmail.com>
---
include/linux/cr.h | 26 +++
include/linux/pid.h | 2
include/linux/pid_namespace.h | 2
kernel/cr/Kconfig | 1
kernel/cr/Makefile | 1
kernel/cr/cpt-sys.c | 12 +
kernel/cr/cr-file.c | 10 +
kernel/cr/cr-nsproxy.c | 15 +
kernel/cr/cr-pid.c | 363 ++++++++++++++++++++++++++++++++++++++++++
kernel/cr/cr-task.c | 18 ++
kernel/cr/cr.h | 8
kernel/fork.c | 2
kernel/pid.c | 39 ++++
kernel/pid_namespace.c | 4
14 files changed, 496 insertions(+), 7 deletions(-)
--- a/include/linux/cr.h
+++ b/include/linux/cr.h
@@ -37,6 +37,8 @@ struct cr_object_header {
#define CR_OBJ_VMA_VDSO 6
#define CR_OBJ_NSPROXY 7
#define CR_OBJ_UTS_NS 8
+#define CR_OBJ_PID_NS 9
+#define CR_OBJ_PID 10
__u32 cr_type; /* object type */
__u32 cr_len; /* object length in bytes including header */
} __packed;
@@ -56,6 +58,7 @@ struct cr_image_task_struct {
cr_pos_t cr_pos_real_parent;
cr_pos_t cr_pos_mm;
+ cr_pos_t cr_pos_pids[3];
cr_pos_t cr_pos_nsproxy;
__u8 cr_comm[16];
@@ -153,6 +156,7 @@ struct cr_image_nsproxy {
struct cr_object_header cr_hdr;
cr_pos_t cr_pos_uts_ns;
+ cr_pos_t cr_pos_pid_ns;
} __packed;
struct cr_image_uts_ns {
@@ -166,6 +170,13 @@ struct cr_image_uts_ns {
__u8 cr_domainname[64];
} __packed;
+struct cr_image_pid_ns {
+ struct cr_object_header cr_hdr;
+
+ cr_pos_t cr_pos_parent; /* CR_POS_UNDEF if root pid_ns */
+ __u32 cr_last_pid;
+} __packed;
+
struct cr_image_mm_struct {
struct cr_object_header cr_hdr;
@@ -223,7 +234,22 @@ struct cr_image_file {
__u32 cr_i_mode;
__u32 cr_f_flags;
__u64 cr_f_pos;
+ struct {
+ cr_pos_t cr_pos_pid;
+ __u32 cr_pid_type;
+ __u32 cr_uid;
+ __u32 cr_euid;
+ __u32 cr_signum;
+ } cr_f_owner;
__u32 cr_name_len;
/* __u8 cr_name[cr_name_len] */
} __packed;
+
+struct cr_image_pid {
+ struct cr_object_header cr_hdr;
+
+ cr_pos_t cr_pos_pid_ns; /* position of last pid_ns */
+ __u32 cr_level;
+ __u32 cr_nr[1]; /* cr_nr[cr_level + 1] */
+} __packed;
#endif
--- a/include/linux/pid.h
+++ b/include/linux/pid.h
@@ -119,7 +119,7 @@ extern struct pid *find_get_pid(int nr);
extern struct pid *find_ge_pid(int nr, struct pid_namespace *);
int next_pidmap(struct pid_namespace *pid_ns, int last);
-extern struct pid *alloc_pid(struct pid_namespace *ns);
+extern struct pid *alloc_pid(struct pid_namespace *ns, int *cr_nr, unsigned int cr_level);
extern void free_pid(struct pid *pid);
/*
--- a/include/linux/pid_namespace.h
+++ b/include/linux/pid_namespace.h
@@ -42,6 +42,8 @@ static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
return ns;
}
+struct pid_namespace *create_pid_namespace(unsigned int level);
+void destroy_pid_namespace(struct pid_namespace *pid_ns);
extern struct pid_namespace *copy_pid_ns(unsigned long flags, struct pid_namespace *ns);
extern void free_pid_ns(struct kref *kref);
extern void zap_pid_ns_processes(struct pid_namespace *pid_ns);
--- a/kernel/cr/Kconfig
+++ b/kernel/cr/Kconfig
@@ -1,5 +1,6 @@
config CR
bool "Container checkpoint/restart"
+ depends on PID_NS
depends on UTS_NS
select FREEZER
help
--- a/kernel/cr/Makefile
+++ b/kernel/cr/Makefile
@@ -4,6 +4,7 @@ cr-y += cr-context.o
cr-y += cr-file.o
cr-y += cr-mm.o
cr-y += cr-nsproxy.o
+cr-y += cr-pid.o
cr-y += cr-task.o
cr-y += cr-uts.o
cr-$(CONFIG_X86_32) += cr-x86_32.o
--- a/kernel/cr/cpt-sys.c
+++ b/kernel/cr/cpt-sys.c
@@ -71,12 +71,18 @@ static int cr_collect(struct cr_context *ctx)
rv = cr_collect_all_uts_ns(ctx);
if (rv < 0)
return rv;
+ rv = cr_collect_all_pid_ns(ctx);
+ if (rv < 0)
+ return rv;
rv = cr_collect_all_mm_struct(ctx);
if (rv < 0)
return rv;
rv = cr_collect_all_file(ctx);
if (rv < 0)
return rv;
+ rv = cr_collect_all_pid(ctx);
+ if (rv < 0)
+ return rv;
return 0;
}
@@ -110,6 +116,12 @@ static int cr_dump(struct cr_context *ctx)
rv = cr_dump_image_header(ctx);
if (rv < 0)
return rv;
+ rv = cr_dump_all_pid_ns(ctx);
+ if (rv < 0)
+ return rv;
+ rv = cr_dump_all_pid(ctx);
+ if (rv < 0)
+ return rv;
rv = cr_dump_all_file(ctx);
if (rv < 0)
return rv;
--- a/kernel/cr/cr-file.c
+++ b/kernel/cr/cr-file.c
@@ -92,6 +92,7 @@ int generic_file_checkpoint(struct file *file, struct cr_context *ctx)
{
struct cr_object *obj;
struct cr_image_file *i;
+ struct cr_object *tmp;
struct kstat stat;
char *buf, *name;
int rv;
@@ -109,6 +110,15 @@ int generic_file_checkpoint(struct file *file, struct cr_context *ctx)
i->cr_i_mode = stat.mode;
i->cr_f_flags = file->f_flags;
i->cr_f_pos = file->f_pos;
+ if (file->f_owner.pid) {
+ tmp = cr_find_obj_by_ptr(ctx, file->f_owner.pid, CR_CTX_PID);
+ i->cr_f_owner.cr_pos_pid = tmp->o_pos;
+ } else
+ i->cr_f_owner.cr_pos_pid = CR_POS_UNDEF;
+ i->cr_f_owner.cr_pid_type = file->f_owner.pid_type;
+ i->cr_f_owner.cr_uid = file->f_owner.uid;
+ i->cr_f_owner.cr_euid = file->f_owner.euid;
+ i->cr_f_owner.cr_signum = file->f_owner.signum;
buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
if (!buf) {
--- a/kernel/cr/cr-nsproxy.c
+++ b/kernel/cr/cr-nsproxy.c
@@ -59,6 +59,8 @@ static int cr_dump_nsproxy(struct cr_context *ctx, struct cr_object *obj)
tmp = cr_find_obj_by_ptr(ctx, nsproxy->uts_ns, CR_CTX_UTS_NS);
i->cr_pos_uts_ns = tmp->o_pos;
+ tmp = cr_find_obj_by_ptr(ctx, nsproxy->pid_ns, CR_CTX_PID_NS);
+ i->cr_pos_pid_ns = tmp->o_pos;
obj->o_pos = ctx->cr_dump_file->f_pos;
rv = cr_write(ctx, i, sizeof(*i));
@@ -84,6 +86,7 @@ static int __cr_restore_nsproxy(struct cr_context *ctx, loff_t pos)
struct cr_image_nsproxy *i;
struct nsproxy *nsproxy;
struct uts_namespace *uts_ns;
+ struct pid_namespace *pid_ns;
struct cr_object *obj, *tmp;
int rv;
@@ -127,7 +130,17 @@ static int __cr_restore_nsproxy(struct cr_context *ctx, loff_t pos)
get_mnt_ns(init_nsproxy.mnt_ns);
nsproxy->mnt_ns = init_nsproxy.mnt_ns;
- nsproxy->pid_ns = get_pid_ns(&init_pid_ns);
+ tmp = cr_find_obj_by_pos(ctx, i->cr_pos_pid_ns, CR_CTX_PID_NS);
+ if (!tmp) {
+ rv = cr_restore_pid_ns(ctx, i->cr_pos_pid_ns);
+ if (rv < 0) {
+ kfree(i);
+ return rv;
+ }
+ tmp = cr_find_obj_by_pos(ctx, i->cr_pos_pid_ns, CR_CTX_PID_NS);
+ }
+ pid_ns = tmp->o_obj;
+ nsproxy->pid_ns = get_pid_ns(pid_ns);
#ifdef CONFIG_NET
nsproxy->net_ns = get_net(&init_net);
new file mode 100644
--- /dev/null
+++ b/kernel/cr/cr-pid.c
@@ -0,0 +1,363 @@
+/* Copyright (C) 2000-2009 Parallels Holdings, Ltd. */
+#include <linux/fs.h>
+#include <linux/nsproxy.h>
+#include <linux/pid_namespace.h>
+#include <linux/proc_fs.h>
+#include <linux/sched.h>
+#include <linux/tty.h>
+
+#include <linux/cr.h>
+#include "cr.h"
+
+static int cr_check_pid_ns(struct pid_namespace *pid_ns)
+{
+#ifdef CONFIG_BSD_PROCESS_ACCT
+ if (pid_ns->bacct) {
+ WARN_ON(1);
+ return -EINVAL;
+ }
+#endif
+ return 0;
+}
+
+static int cr_collect_pid_ns(struct cr_context *ctx, struct pid_namespace *pid_ns)
+{
+ int rv;
+
+ rv = cr_check_pid_ns(pid_ns);
+ if (rv < 0)
+ return rv;
+ rv = cr_collect_object(ctx, pid_ns, CR_CTX_PID_NS);
+ printk("collect pid_ns %p: rv %d\n", pid_ns, rv);
+ return rv;
+}
+
+int cr_collect_all_pid_ns(struct cr_context *ctx)
+{
+ struct cr_object *obj;
+ int rv;
+
+ for_each_cr_object(ctx, obj, CR_CTX_NSPROXY) {
+ struct nsproxy *nsproxy = obj->o_obj;
+
+ rv = cr_collect_pid_ns(ctx, nsproxy->pid_ns);
+ if (rv < 0)
+ return rv;
+ }
+ /*
+ * FIXME: check for external pid_ns references
+ * 1. struct pid pins pid_ns
+ * 2. struct pid_namespace pins pid_ns, but only parent one
+ */
+ return 0;
+}
+
+static int cr_dump_pid_ns(struct cr_context *ctx, struct cr_object *obj)
+{
+ struct pid_namespace *pid_ns = obj->o_obj;
+ struct cr_image_pid_ns *i;
+ struct cr_object *tmp;
+ int rv;
+
+ printk("dump pid_ns %p\n", pid_ns);
+
+ i = cr_prepare_image(CR_OBJ_PID_NS, sizeof(*i));
+ if (!i)
+ return -ENOMEM;
+
+ i->cr_last_pid = pid_ns->last_pid;
+ if (pid_ns == ctx->cr_init_tsk->nsproxy->pid_ns)
+ i->cr_pos_parent = CR_POS_UNDEF;
+ else {
+ tmp = cr_find_obj_by_ptr(ctx, pid_ns->parent, CR_CTX_PID_NS);
+ i->cr_pos_parent = tmp->o_pos;
+ }
+
+ obj->o_pos = ctx->cr_dump_file->f_pos;
+ rv = cr_write(ctx, i, sizeof(*i));
+ kfree(i);
+ return rv;
+}
+
+int cr_dump_all_pid_ns(struct cr_context *ctx)
+{
+ struct cr_object *obj;
+ unsigned int level, nr_found;
+ int rv;
+
+ /*
+ * Unlike other namespaces, pid_ns have direct hierarchy via ->parent.
+ * To not create problems on dump with missing references and seeking
+ * through dumpfile, dump pid_ns in certain order: lower ->level one
+ * goes first.
+ *
+ * On restart, for every pid_ns being restored (except root one),
+ * it's parent pid_ns will be already restored and reachable
+ * via lookup by file position.
+ *
+ * pid_ns pins parent one, so there are no holes in hierarchy
+ * wrt ->level which means loop is finite.
+ */
+ level = ctx->cr_init_tsk->nsproxy->pid_ns->level;
+ do {
+ nr_found = 0;
+ for_each_cr_object(ctx, obj, CR_CTX_PID_NS) {
+ struct pid_namespace *pid_ns = obj->o_obj;
+
+ if (pid_ns->level != level)
+ continue;
+ rv = cr_dump_pid_ns(ctx, obj);
+ if (rv < 0)
+ return rv;
+ nr_found++;
+ }
+ level++;
+ } while (nr_found != 0);
+ return 0;
+}
+
+int cr_restore_pid_ns(struct cr_context *ctx, loff_t pos)
+{
+ struct pid_namespace *parent_pid_ns, *pid_ns;
+ struct cr_image_pid_ns *i;
+ struct cr_object *obj, *tmp;
+ int rv;
+
+ i = kzalloc(sizeof(struct cr_image_pid_ns), GFP_KERNEL);
+ if (!i)
+ return -ENOMEM;
+ rv = cr_pread(ctx, i, sizeof(*i), pos);
+ if (rv < 0) {
+ kfree(i);
+ return rv;
+ }
+ if (i->cr_hdr.cr_type != CR_OBJ_PID_NS) {
+ kfree(i);
+ return -EINVAL;
+ }
+
+ if (i->cr_pos_parent != CR_POS_UNDEF) {
+ tmp = cr_find_obj_by_pos(ctx, i->cr_pos_parent, CR_CTX_PID_NS);
+ if (!tmp) {
+ /* FIXME recursion */
+ rv = cr_restore_pid_ns(ctx, i->cr_pos_parent);
+ if (rv < 0)
+ return rv;
+ tmp = cr_find_obj_by_pos(ctx, i->cr_pos_parent, CR_CTX_PID_NS);
+ }
+ parent_pid_ns = tmp->o_obj;
+ } else
+ parent_pid_ns = ctx->cr_init_tsk->nsproxy->pid_ns;
+ pid_ns = create_pid_namespace(parent_pid_ns->level + 1);
+ if (IS_ERR(pid_ns)) {
+ kfree(i);
+ return PTR_ERR(pid_ns);
+ }
+ rv = pid_ns_prepare_proc(pid_ns);
+ if (rv < 0) {
+ destroy_pid_namespace(pid_ns);
+ return rv;
+ }
+ pid_ns->parent = get_pid_ns(parent_pid_ns);
+
+ pid_ns->last_pid = i->cr_last_pid;
+ pid_ns->child_reaper = current;
+ kfree(i);
+
+ obj = cr_object_create(pid_ns);
+ if (!obj) {
+ put_pid_ns(pid_ns->parent);
+ pid_ns_release_proc(pid_ns);
+ destroy_pid_namespace(pid_ns);
+ return -ENOMEM;
+ }
+ obj->o_pos = pos;
+ list_add(&obj->o_list, &ctx->cr_obj[CR_CTX_PID_NS]);
+ printk("restore pid_ns %p, pos %lld\n", pid_ns, (long long)pos);
+ return 0;
+}
+
+static int cr_collect_pid(struct cr_context *ctx, struct pid *pid)
+{
+ int rv;
+
+ rv = cr_collect_object(ctx, pid, CR_CTX_PID);
+ printk("collect pid %p: rv %d\n", pid, rv);
+ return rv;
+}
+
+int cr_collect_all_pid(struct cr_context *ctx)
+{
+ struct cr_object *obj;
+ unsigned int level0;
+ int rv;
+
+ level0 = ctx->cr_init_tsk->nsproxy->pid_ns->level;
+ for_each_cr_object(ctx, obj, CR_CTX_TASK_STRUCT) {
+ struct task_struct *tsk = obj->o_obj;
+ struct pid *pid;
+
+ BUILD_BUG_ON(PIDTYPE_MAX != 3);
+ pid = tsk->pids[PIDTYPE_PID].pid;
+ BUG_ON(pid->level < level0);
+ rv = cr_collect_pid(ctx, pid);
+ if (rv < 0)
+ return rv;
+ pid = tsk->pids[PIDTYPE_PGID].pid;
+ if (pid->level >= level0) {
+ rv = cr_collect_pid(ctx, pid);
+ if (rv < 0)
+ return rv;
+ }
+ pid = tsk->pids[PIDTYPE_SID].pid;
+ if (pid->level >= level0) {
+ rv = cr_collect_pid(ctx, pid);
+ if (rv < 0)
+ return rv;
+ }
+ }
+ for_each_cr_object(ctx, obj, CR_CTX_FILE) {
+ struct file *file = obj->o_obj;
+ struct pid *pid = file->f_owner.pid;
+
+ if (pid) {
+ rv = cr_collect_pid(ctx, pid);
+ if (rv < 0)
+ return rv;
+ }
+ }
+ /* FIXME pid refcount check should account references from proc inodes */
+ return 0;
+}
+
+static int cr_dump_pid(struct cr_context *ctx, struct cr_object *obj)
+{
+ struct pid *pid = obj->o_obj;
+ struct cr_image_pid *i;
+ struct cr_object *tmp;
+ size_t image_len;
+ unsigned int level0, level;
+ int rv;
+
+ printk("dump pid %p\n", pid);
+
+ level0 = ctx->cr_init_tsk->nsproxy->pid_ns->level;
+ BUG_ON(pid->level < level0);
+ image_len = sizeof(*i) + (pid->level - level0) * sizeof(__u32);
+
+ i = cr_prepare_image(CR_OBJ_PID, image_len);
+ if (!i)
+ return -ENOMEM;
+
+ tmp = cr_find_obj_by_ptr(ctx, pid->numbers[pid->level].ns, CR_CTX_PID_NS);
+ i->cr_pos_pid_ns = tmp->o_pos;
+ i->cr_level = pid->level - level0;
+ for (level = level0; level <= pid->level; level++)
+ i->cr_nr[level - level0] = pid->numbers[level].nr;
+
+ obj->o_pos = ctx->cr_dump_file->f_pos;
+ rv = cr_write(ctx, i, image_len);
+ kfree(i);
+ return rv;
+}
+
+int cr_dump_all_pid(struct cr_context *ctx)
+{
+ struct cr_object *obj;
+ int rv;
+
+ for_each_cr_object(ctx, obj, CR_CTX_PID) {
+ rv = cr_dump_pid(ctx, obj);
+ if (rv < 0)
+ return rv;
+ }
+ return 0;
+}
+
+static int __cr_restore_pid(struct cr_context *ctx, loff_t pos)
+{
+ struct cr_image_pid *i, *tmpi;
+ struct pid_namespace *pid_ns;
+ struct pid *pid;
+ struct cr_object *obj, *tmp;
+ size_t image_len;
+ int rv;
+
+ i = kzalloc(sizeof(*i), GFP_KERNEL);
+ if (!i)
+ return -ENOMEM;
+ rv = cr_pread(ctx, i, sizeof(*i), pos);
+ if (rv < 0) {
+ kfree(i);
+ return rv;
+ }
+ if (i->cr_hdr.cr_type != CR_OBJ_PID) {
+ kfree(i);
+ return -EINVAL;
+ }
+ /* Image of struct pid is variable-sized. */
+ image_len = sizeof(*i) + i->cr_level * sizeof(__u32);
+ tmpi = i;
+ i = krealloc(i, image_len, GFP_KERNEL);
+ if (!i) {
+ kfree(tmpi);
+ return -ENOMEM;
+ }
+ rv = cr_pread(ctx, &i->cr_nr[1], image_len - sizeof(*i), pos + sizeof(*i));
+ if (rv < 0) {
+ kfree(i);
+ return rv;
+ }
+
+ tmp = cr_find_obj_by_pos(ctx, i->cr_pos_pid_ns, CR_CTX_PID_NS);
+ if (!tmp) {
+ rv = cr_restore_pid_ns(ctx, i->cr_pos_pid_ns);
+ if (rv < 0) {
+ kfree(i);
+ return rv;
+ }
+ tmp = cr_find_obj_by_pos(ctx, i->cr_pos_pid_ns, CR_CTX_PID_NS);
+ }
+ pid_ns = tmp->o_obj;
+
+ pid = alloc_pid(pid_ns, i->cr_nr, i->cr_level);
+ kfree(i);
+ if (!pid)
+ return -ENOMEM;
+
+ obj = cr_object_create(pid);
+ if (!obj) {
+ put_pid(pid);
+ return -ENOMEM;
+ }
+ obj->o_pos = pos;
+ list_add(&obj->o_list, &ctx->cr_obj[CR_CTX_PID]);
+ printk("restore pid %p, pos %lld\n", pid, (long long)pos);
+ return 0;
+}
+
+int cr_restore_pid(struct cr_context *ctx, struct cr_image_task_struct *i)
+{
+ struct task_struct *tsk = current;
+ struct pid *pid;
+ struct cr_object *tmp;
+ int rv;
+
+ if (i->cr_pos_pids[0] != CR_POS_UNDEF) {
+ tmp = cr_find_obj_by_pos(ctx, i->cr_pos_pids[0], CR_CTX_PID);
+ if (!tmp) {
+ rv = __cr_restore_pid(ctx, i->cr_pos_pids[0]);
+ if (rv < 0)
+ return rv;
+ tmp = cr_find_obj_by_pos(ctx, i->cr_pos_pids[0], CR_CTX_PID);
+ }
+ pid = tmp->o_obj;
+ write_lock(&tasklist_lock);
+ change_pid(tsk, PIDTYPE_PID, get_pid(pid));
+ tsk->pid = tsk->tgid = pid_nr(pid);
+ write_unlock(&tasklist_lock);
+ }
+ /* FIXME PIDTYPE_PGID */
+ /* FIXME PIDTYPE_SID */
+ return 0;
+}
--- a/kernel/cr/cr-task.c
+++ b/kernel/cr/cr-task.c
@@ -2,6 +2,7 @@
#include <linux/fs.h>
#include <linux/kthread.h>
#include <linux/nsproxy.h>
+#include <linux/pid.h>
#include <linux/pid_namespace.h>
#include <linux/sched.h>
#include <linux/tty.h>
@@ -113,6 +114,20 @@ static int cr_dump_task_struct(struct cr_context *ctx, struct cr_object *obj)
tmp = cr_find_obj_by_ptr(ctx, tsk->nsproxy, CR_CTX_NSPROXY);
i->cr_pos_nsproxy = tmp->o_pos;
+ BUILD_BUG_ON(PIDTYPE_MAX != 3);
+ tmp = cr_find_obj_by_ptr(ctx, tsk->pids[PIDTYPE_PID].pid, CR_CTX_PID);
+ i->cr_pos_pids[0] = tmp->o_pos;
+ tmp = cr_find_obj_by_ptr(ctx, tsk->pids[PIDTYPE_PGID].pid, CR_CTX_PID);
+ if (tmp)
+ i->cr_pos_pids[1] = tmp->o_pos;
+ else
+ i->cr_pos_pids[1] = CR_POS_UNDEF;
+ tmp = cr_find_obj_by_ptr(ctx, tsk->pids[PIDTYPE_SID].pid, CR_CTX_PID);
+ if (tmp)
+ i->cr_pos_pids[2] = tmp->o_pos;
+ else
+ i->cr_pos_pids[2] = CR_POS_UNDEF;
+
BUILD_BUG_ON(TASK_COMM_LEN != 16);
strlcpy((char *)i->cr_comm, (const char *)tsk->comm, sizeof(i->cr_comm));
@@ -171,6 +186,9 @@ static int task_struct_restorer(void *_tsk_ctx)
rv = cr_restore_nsproxy(ctx, i->cr_pos_nsproxy);
if (rv < 0)
goto out;
+ rv = cr_restore_pid(ctx, i);
+ if (rv < 0)
+ goto out;
rv = 0;
out:
--- a/kernel/cr/cr.h
+++ b/kernel/cr/cr.h
@@ -25,6 +25,8 @@ enum cr_context_obj_type {
CR_CTX_FILE,
CR_CTX_MM_STRUCT,
CR_CTX_NSPROXY,
+ CR_CTX_PID,
+ CR_CTX_PID_NS,
CR_CTX_TASK_STRUCT,
CR_CTX_UTS_NS,
NR_CR_CTX_TYPES
@@ -71,18 +73,24 @@ static inline void __user *cr_restore_ptr(__u64 ptr)
int cr_collect_all_file(struct cr_context *ctx);
int cr_collect_all_mm_struct(struct cr_context *ctx);
int cr_collect_all_nsproxy(struct cr_context *ctx);
+int cr_collect_all_pid_ns(struct cr_context *ctx);
+int cr_collect_all_pid(struct cr_context *ctx);
int cr_collect_all_task_struct(struct cr_context *ctx);
int cr_collect_all_uts_ns(struct cr_context *ctx);
int cr_dump_all_file(struct cr_context *ctx);
int cr_dump_all_mm_struct(struct cr_context *ctx);
int cr_dump_all_nsproxy(struct cr_context *ctx);
+int cr_dump_all_pid_ns(struct cr_context *ctx);
+int cr_dump_all_pid(struct cr_context *ctx);
int cr_dump_all_task_struct(struct cr_context *ctx);
int cr_dump_all_uts_ns(struct cr_context *ctx);
int cr_restore_file(struct cr_context *ctx, loff_t pos);
int cr_restore_mm_struct(struct cr_context *ctx, loff_t pos);
int cr_restore_nsproxy(struct cr_context *ctx, loff_t pos);
+int cr_restore_pid_ns(struct cr_context *ctx, loff_t pos);
+int cr_restore_pid(struct cr_context *ctx, struct cr_image_task_struct *i);
int cr_restore_task_struct(struct cr_context *ctx, loff_t pos);
int cr_restore_uts_ns(struct cr_context *ctx, loff_t pos);
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1112,7 +1112,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
if (pid != &init_struct_pid) {
retval = -ENOMEM;
- pid = alloc_pid(p->nsproxy->pid_ns);
+ pid = alloc_pid(p->nsproxy->pid_ns, NULL, 0);
if (!pid)
goto bad_fork_cleanup_io;
--- a/kernel/pid.c
+++ b/kernel/pid.c
@@ -182,6 +182,36 @@ static int alloc_pidmap(struct pid_namespace *pid_ns)
return -1;
}
+#ifdef CONFIG_CR
+static int set_pidmap(struct pid_namespace *pid_ns, pid_t pid)
+{
+ int offset;
+ struct pidmap *map;
+
+ offset = pid & BITS_PER_PAGE_MASK;
+ map = &pid_ns->pidmap[pid/BITS_PER_PAGE];
+ if (!map->page) {
+ void *page = kzalloc(PAGE_SIZE, GFP_KERNEL);
+ /*
+ * Free the page if someone raced with us
+ * installing it:
+ */
+ spin_lock_irq(&pidmap_lock);
+ if (map->page)
+ kfree(page);
+ else
+ map->page = page;
+ spin_unlock_irq(&pidmap_lock);
+ if (unlikely(!map->page))
+ return -ENOMEM;
+ }
+ if (test_and_set_bit(offset, map->page))
+ return -EBUSY;
+ atomic_dec(&map->nr_free);
+ return pid;
+}
+#endif
+
int next_pidmap(struct pid_namespace *pid_ns, int last)
{
int offset;
@@ -239,7 +269,7 @@ void free_pid(struct pid *pid)
call_rcu(&pid->rcu, delayed_put_pid);
}
-struct pid *alloc_pid(struct pid_namespace *ns)
+struct pid *alloc_pid(struct pid_namespace *ns, int *cr_nr, unsigned int cr_level)
{
struct pid *pid;
enum pid_type type;
@@ -253,7 +283,12 @@ struct pid *alloc_pid(struct pid_namespace *ns)
tmp = ns;
for (i = ns->level; i >= 0; i--) {
- nr = alloc_pidmap(tmp);
+#ifdef CONFIG_CR
+ if (cr_nr && ns->level - i <= cr_level)
+ nr = set_pidmap(tmp, cr_nr[ns->level - i]);
+ else
+#endif
+ nr = alloc_pidmap(tmp);
if (nr < 0)
goto out_free;
--- a/kernel/pid_namespace.c
+++ b/kernel/pid_namespace.c
@@ -67,7 +67,7 @@ err_alloc:
return NULL;
}
-static struct pid_namespace *create_pid_namespace(unsigned int level)
+struct pid_namespace *create_pid_namespace(unsigned int level)
{
struct pid_namespace *ns;
int i;
@@ -103,7 +103,7 @@ out:
return ERR_PTR(-ENOMEM);
}
-static void destroy_pid_namespace(struct pid_namespace *ns)
+void destroy_pid_namespace(struct pid_namespace *ns)
{
int i;
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