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kernel: Update kernel patches

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Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
This commit is contained in:
Cyrill Gorcunov
2011-12-13 12:39:15 +04:00
parent 950e788b1c
commit 093e4f35c3
15 changed files with 625 additions and 157 deletions
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46
kernel/c-r-introduce-checkpoint_restore-symbol.patch Normal file
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@@ -0,0 +1,46 @@
From: Cyrill Gorcunov <gorcunov@openvz.org>
Subject: c/r: introduce CHECKPOINT_RESTORE symbol
For checkpoint/restore we need auxilary features being compiled into the
kernel, such as additional prctl codes, /proc/<pid>/map_files and etc...
but same time these features are not mandatory for a regular kernel so
CHECKPOINT_RESTORE config symbol should bring a way to disable them all at
once if one wish to get rid of additional functionality.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrew Vagin <avagin@openvz.org>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Vasiliy Kulikov <segoon@openwall.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
init/Kconfig | 11 +++++++++++
1 file changed, 11 insertions(+)
Index: linux-2.6.git/init/Kconfig
===================================================================
--- linux-2.6.git.orig/init/Kconfig
+++ linux-2.6.git/init/Kconfig
@@ -773,6 +773,17 @@ config DEBUG_BLK_CGROUP
endif # CGROUPS
+config CHECKPOINT_RESTORE
+ bool "Checkpoint/restore support" if EXPERT
+ default n
+ help
+ Enables additional kernel features in a sake of checkpoint/restore.
+ In particular it adds auxiliary prctl codes to setup process text,
+ data and heap segment sizes, and a few additional /proc filesystem
+ entries.
+
+ If unsure, say N here.
+
menuconfig NAMESPACES
bool "Namespaces support" if EXPERT
default !EXPERT

117
kernel/c-r-prctl-add-pr_set_mm-codes-to-set-up-mm_struct-entries-fix.patch Normal file
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@@ -0,0 +1,117 @@
From: Andrew Morton <akpm@linux-foundation.org>
Subject: c-r-prctl-add-pr_set_mm-codes-to-set-up-mm_struct-entries-fix
cache current->mm in a local, saving 200 bytes text
Cc: Andrew Vagin <avagin@openvz.org>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vasiliy Kulikov <segoon@openwall.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
kernel/sys.c | 33 +++++++++++++++++----------------
1 file changed, 17 insertions(+), 16 deletions(-)
Index: linux-2.6.git/kernel/sys.c
===================================================================
--- linux-2.6.git.orig/kernel/sys.c
+++ linux-2.6.git/kernel/sys.c
@@ -1701,6 +1701,7 @@ static int prctl_set_mm(int opt, unsigne
unsigned long vm_bad_flags;
struct vm_area_struct *vma;
int error = 0;
+ struct mm_struct *mm = current->mm;
if (arg4 | arg5)
return -EINVAL;
@@ -1711,8 +1712,8 @@ static int prctl_set_mm(int opt, unsigne
if (addr >= TASK_SIZE)
return -EINVAL;
- down_read(&current->mm->mmap_sem);
- vma = find_vma(current->mm, addr);
+ down_read(&mm->mmap_sem);
+ vma = find_vma(mm, addr);
if (opt != PR_SET_MM_START_BRK && opt != PR_SET_MM_BRK) {
/* It must be existing VMA */
@@ -1732,9 +1733,9 @@ static int prctl_set_mm(int opt, unsigne
goto out;
if (opt == PR_SET_MM_START_CODE)
- current->mm->start_code = addr;
+ mm->start_code = addr;
else
- current->mm->end_code = addr;
+ mm->end_code = addr;
break;
case PR_SET_MM_START_DATA:
@@ -1747,9 +1748,9 @@ static int prctl_set_mm(int opt, unsigne
goto out;
if (opt == PR_SET_MM_START_DATA)
- current->mm->start_data = addr;
+ mm->start_data = addr;
else
- current->mm->end_data = addr;
+ mm->end_data = addr;
break;
case PR_SET_MM_START_STACK:
@@ -1762,31 +1763,31 @@ static int prctl_set_mm(int opt, unsigne
if ((vma->vm_flags & vm_req_flags) != vm_req_flags)
goto out;
- current->mm->start_stack = addr;
+ mm->start_stack = addr;
break;
case PR_SET_MM_START_BRK:
- if (addr <= current->mm->end_data)
+ if (addr <= mm->end_data)
goto out;
if (rlim < RLIM_INFINITY &&
- (current->mm->brk - addr) +
- (current->mm->end_data - current->mm->start_data) > rlim)
+ (mm->brk - addr) +
+ (mm->end_data - mm->start_data) > rlim)
goto out;
- current->mm->start_brk = addr;
+ mm->start_brk = addr;
break;
case PR_SET_MM_BRK:
- if (addr <= current->mm->end_data)
+ if (addr <= mm->end_data)
goto out;
if (rlim < RLIM_INFINITY &&
- (addr - current->mm->start_brk) +
- (current->mm->end_data - current->mm->start_data) > rlim)
+ (addr - mm->start_brk) +
+ (mm->end_data - mm->start_data) > rlim)
goto out;
- current->mm->brk = addr;
+ mm->brk = addr;
break;
default:
@@ -1797,7 +1798,7 @@ static int prctl_set_mm(int opt, unsigne
error = 0;
out:
- up_read(&current->mm->mmap_sem);
+ up_read(&mm->mmap_sem);
return error;
}

104
kernel/prctl-tune-up-mm_struct-members-2 → kernel/c-r-prctl-add-pr_set_mm-codes-to-set-up-mm_struct-entries.patch
View File

@@ -1,28 +1,48 @@
prctl: Add PR_SET_MM codes to tune up mm_struct entires v2
From: Cyrill Gorcunov <gorcunov@openvz.org>
Subject: c/r: prctl: add PR_SET_MM codes to set up mm_struct entries
A few members of mm_struct such as start_code, end_code,
start_data, end_data, start_stack, start_brk, brk provided
by the kernel via /proc/$pid/stat and we use it at checkpoint
time.
When we restore a task we need to set up text, data and data heap sizes
from userspace to the values a task had at checkpoint time. This patch
adds auxilary prctl codes for that.
At restore time we need a mechanism to restore those values
back and for this sake PR_SET_MM prctl code is introduced.
While most of them have a statistical nature (their values are involved
into calculation of /proc/<pid>/statm output) the start_brk and brk values
are used to compute an allowed size of program data segment expansion.
Which means an arbitrary changes of this values might be dangerous
operation. So to restrict access the following requirements applied to
prctl calls:
Note because of being a dangerous operation this inteface
is allowed for CAP_SYS_ADMIN only.
- The process has to have CAP_SYS_ADMIN capability granted.
- For all opcodes except start_brk/brk members an appropriate
VMA area must exist and should fit certain VMA flags,
such as:
- code segment must be executable but not writable;
- data segment must not be executable.
v2:
- Add a check for vma start address, testing for vma ending
address is not enough. From Kees Cook.
start_brk/brk values must not intersect with data segment and must not
exceed RLIMIT_DATA resource limit.
- Add some sanity tests for assigned addresses.
Still the main guard is CAP_SYS_ADMIN capability check.
Note the kernel should be compiled with CONFIG_CHECKPOINT_RESTORE support
otherwise these prctl calls will return -EINVAL.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
CC: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrew Vagin <avagin@openvz.org>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Vasiliy Kulikov <segoon@openwall.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
include/linux/prctl.h | 12 +++++
kernel/sys.c | 118 ++++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 130 insertions(+)
kernel/sys.c | 120 ++++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 132 insertions(+)
Index: linux-2.6.git/include/linux/prctl.h
===================================================================
@@ -49,34 +69,33 @@ Index: linux-2.6.git/kernel/sys.c
===================================================================
--- linux-2.6.git.orig/kernel/sys.c
+++ linux-2.6.git/kernel/sys.c
@@ -1692,6 +1692,118 @@ SYSCALL_DEFINE1(umask, int, mask)
@@ -1692,6 +1692,123 @@ SYSCALL_DEFINE1(umask, int, mask)
return mask;
}
+static int prctl_set_mm(int opt, unsigned long addr)
+#ifdef CONFIG_CHECKPOINT_RESTORE
+static int prctl_set_mm(int opt, unsigned long addr,
+ unsigned long arg4, unsigned long arg5)
+{
+ unsigned long rlim = rlimit(RLIMIT_DATA);
+ unsigned long vm_req_flags;
+ unsigned long vm_bad_flags;
+ struct vm_area_struct *vma;
+ struct mm_struct *mm;
+ int error = 0;
+
+ if (arg4 | arg5)
+ return -EINVAL;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ if (addr >= TASK_SIZE)
+ return -EINVAL;
+
+ mm = get_task_mm(current);
+ if (!mm)
+ return -ENOENT;
+ down_read(&current->mm->mmap_sem);
+ vma = find_vma(current->mm, addr);
+
+ down_read(&mm->mmap_sem);
+ vma = find_vma(mm, addr);
+
+ if (opt != PR_SET_MM_START_BRK &&
+ opt != PR_SET_MM_BRK) {
+ if (opt != PR_SET_MM_START_BRK && opt != PR_SET_MM_BRK) {
+ /* It must be existing VMA */
+ if (!vma || vma->vm_start > addr)
+ goto out;
@@ -86,7 +105,6 @@ Index: linux-2.6.git/kernel/sys.c
+ switch (opt) {
+ case PR_SET_MM_START_CODE:
+ case PR_SET_MM_END_CODE:
+
+ vm_req_flags = VM_READ | VM_EXEC;
+ vm_bad_flags = VM_WRITE | VM_MAYSHARE;
+
@@ -102,7 +120,6 @@ Index: linux-2.6.git/kernel/sys.c
+
+ case PR_SET_MM_START_DATA:
+ case PR_SET_MM_END_DATA:
+
+ vm_req_flags = VM_READ | VM_WRITE;
+ vm_bad_flags = VM_EXEC | VM_MAYSHARE;
+
@@ -130,22 +147,24 @@ Index: linux-2.6.git/kernel/sys.c
+ break;
+
+ case PR_SET_MM_START_BRK:
+ if (addr <= mm->end_data)
+ if (addr <= current->mm->end_data)
+ goto out;
+
+ if (rlim < RLIM_INFINITY &&
+ (mm->brk - addr) + (mm->end_data - mm->start_data) > rlim)
+ (current->mm->brk - addr) +
+ (current->mm->end_data - current->mm->start_data) > rlim)
+ goto out;
+
+ current->mm->start_brk = addr;
+ break;
+
+ case PR_SET_MM_BRK:
+ if (addr <= mm->end_data)
+ if (addr <= current->mm->end_data)
+ goto out;
+
+ if (rlim < RLIM_INFINITY &&
+ (addr - mm->start_brk) + (mm->end_data - mm->start_data) > rlim)
+ (addr - current->mm->start_brk) +
+ (current->mm->end_data - current->mm->start_data) > rlim)
+ goto out;
+
+ current->mm->brk = addr;
@@ -159,25 +178,28 @@ Index: linux-2.6.git/kernel/sys.c
+ error = 0;
+
+out:
+ up_read(&mm->mmap_sem);
+ mmput(mm);
+ up_read(&current->mm->mmap_sem);
+
+ return error;
+}
+#else /* CONFIG_CHECKPOINT_RESTORE */
+static int prctl_set_mm(int opt, unsigned long addr,
+ unsigned long arg4, unsigned long arg5)
+{
+ return -EINVAL;
+}
+#endif
+
SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
unsigned long, arg4, unsigned long, arg5)
{
@@ -1841,6 +1953,12 @@ SYSCALL_DEFINE5(prctl, int, option, unsi
@@ -1841,6 +1958,9 @@ SYSCALL_DEFINE5(prctl, int, option, unsi
else
error = PR_MCE_KILL_DEFAULT;
break;
+ case PR_SET_MM: {
+ if (arg4 | arg5)
+ return -EINVAL;
+ error = prctl_set_mm(arg2, arg3);
+ case PR_SET_MM:
+ error = prctl_set_mm(arg2, arg3, arg4, arg5);
+ break;
+ }
default:
error = -EINVAL;
break;

31
kernel/c-r-procfs-add-start_data-end_data-start_brk-members-to-proc-pid-stat-v4-fix.patch Normal file
View File

@@ -0,0 +1,31 @@
From: Andrew Morton <akpm@linux-foundation.org>
Subject: c-r-procfs-add-start_data-end_data-start_brk-members-to-proc-pid-stat-v4-fix
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrew Vagin <avagin@openvz.org>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vasiliy Kulikov <segoon@openwall.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
Documentation/filesystems/proc.txt | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
Index: linux-2.6.git/Documentation/filesystems/proc.txt
===================================================================
--- linux-2.6.git.orig/Documentation/filesystems/proc.txt
+++ linux-2.6.git/Documentation/filesystems/proc.txt
@@ -307,7 +307,7 @@ Table 1-4: Contents of the stat files (a
cgtime guest time of the task children in jiffies
start_data address above which program data+bss is placed
end_data address below which program data+bss is placed
- start_brk address above which program heap can be expaned with brk() call
+ start_brk address above which program heap can be expanded with brk()
..............................................................................
The /proc/PID/maps file containing the currently mapped memory regions and

70
kernel/c-r-procfs-add-start_data-end_data-start_brk-members-to-proc-pid-stat-v4.patch Normal file
View File

@@ -0,0 +1,70 @@
From: Cyrill Gorcunov <gorcunov@openvz.org>
Subject: c/r: procfs: add start_data, end_data, start_brk members to /proc/$pid/stat v4
The mm->start_code/end_code, mm->start_data/end_data, mm->start_brk are
involved into calculation of program text/data segment sizes (which might
be seen in /proc/<pid>/statm) and into brk() call final address.
For restore we need to know all these values. While
mm->start_code/end_code already present in /proc/$pid/stat, the rest
members are not, so this patch brings them in.
The restore procedure of these members is addressed in another patch using
prctl().
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrew Vagin <avagin@openvz.org>
Cc: Vasiliy Kulikov <segoon@openwall.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
Documentation/filesystems/proc.txt | 3 +++
fs/proc/array.c | 7 +++++--
2 files changed, 8 insertions(+), 2 deletions(-)
Index: linux-2.6.git/Documentation/filesystems/proc.txt
===================================================================
--- linux-2.6.git.orig/Documentation/filesystems/proc.txt
+++ linux-2.6.git/Documentation/filesystems/proc.txt
@@ -305,6 +305,9 @@ Table 1-4: Contents of the stat files (a
blkio_ticks time spent waiting for block IO
gtime guest time of the task in jiffies
cgtime guest time of the task children in jiffies
+ start_data address above which program data+bss is placed
+ end_data address below which program data+bss is placed
+ start_brk address above which program heap can be expaned with brk() call
..............................................................................
The /proc/PID/maps file containing the currently mapped memory regions and
Index: linux-2.6.git/fs/proc/array.c
===================================================================
--- linux-2.6.git.orig/fs/proc/array.c
+++ linux-2.6.git/fs/proc/array.c
@@ -464,7 +464,7 @@ static int do_task_stat(struct seq_file
seq_printf(m, "%d (%s) %c %d %d %d %d %d %u %lu \
%lu %lu %lu %lu %lu %ld %ld %ld %ld %d 0 %llu %lu %ld %lu %lu %lu %lu %lu \
-%lu %lu %lu %lu %lu %lu %lu %lu %d %d %u %u %llu %lu %ld\n",
+%lu %lu %lu %lu %lu %lu %lu %lu %d %d %u %u %llu %lu %ld %lu %lu %lu\n",
pid_nr_ns(pid, ns),
tcomm,
state,
@@ -511,7 +511,10 @@ static int do_task_stat(struct seq_file
task->policy,
(unsigned long long)delayacct_blkio_ticks(task),
cputime_to_clock_t(gtime),
- cputime_to_clock_t(cgtime));
+ cputime_to_clock_t(cgtime),
+ (mm && permitted) ? mm->start_data : 0,
+ (mm && permitted) ? mm->end_data : 0,
+ (mm && permitted) ? mm->start_brk : 0);
if (mm)
mmput(mm);
return 0;

37
kernel/fs-proc-Add-start_data-end_data-start_brk-members
View File

@@ -1,37 +0,0 @@
fs, proc: Add start_data, end_data, start_brk members to /proc/$pid/stat
It helps to dump and restore this mm_struct members.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
---
fs/proc/array.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
Index: linux-2.6.git/fs/proc/array.c
===================================================================
--- linux-2.6.git.orig/fs/proc/array.c
+++ linux-2.6.git/fs/proc/array.c
@@ -464,7 +464,7 @@ static int do_task_stat(struct seq_file
seq_printf(m, "%d (%s) %c %d %d %d %d %d %u %lu \
%lu %lu %lu %lu %lu %ld %ld %ld %ld %d 0 %llu %lu %ld %lu %lu %lu %lu %lu \
-%lu %lu %lu %lu %lu %lu %lu %lu %d %d %u %u %llu %lu %ld\n",
+%lu %lu %lu %lu %lu %lu %lu %lu %d %d %u %u %llu %lu %ld %lu %lu %lu\n",
pid_nr_ns(pid, ns),
tcomm,
state,
@@ -511,7 +511,10 @@ static int do_task_stat(struct seq_file
task->policy,
(unsigned long long)delayacct_blkio_ticks(task),
cputime_to_clock_t(gtime),
- cputime_to_clock_t(cgtime));
+ cputime_to_clock_t(cgtime),
+ mm ? (permitted ? mm->start_data : 1) : 0,
+ mm ? (permitted ? mm->end_data : 1) : 0,
+ mm ? (permitted ? mm->start_brk : 1) : 0);
if (mm)
mmput(mm);
return 0;

3
kernel/fs-proc-Introduce-the-proc-pid-map_files-directory
View File

@@ -1,4 +1,5 @@
fs, proc: Introduce the /proc/<pid>/map_files/ directory v14
From: Cyrill Gorcunov <gorcunov@openvz.org>
Subject: [PATCH] fs, proc: Introduce the /proc/<pid>/map_files/ directory v14
From: Pavel Emelyanov <xemul@parallels.com>

3
kernel/fs-proc-Make-proc_get_link-to-use-dentry
View File

@@ -1,4 +1,5 @@
fs, proc: Make proc_get_link to use dentry instead of inode
From: Cyrill Gorcunov <gorcunov@openvz.org>
Subject: [PATCH] fs, proc: Make proc_get_link to use dentry instead of inode
From: Cyrill Gorcunov <gorcunov@openvz.org>

69
kernel/fs-proc-add-children-entry
View File

@@ -1,69 +0,0 @@
fs, proc: Introduce the /proc/<pid>/children entry
There is no easy way to make a reverse parent->children chain
from the task status, in turn children->parent provided with "PPid"
field.
So instead of walking over all pids in system to figure out what
children the task have -- we add explicit /proc/<pid>/children entry,
since kernel already knows this kind of information but it was not
yet exported.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
---
fs/proc/array.c | 14 ++++++++++++++
fs/proc/base.c | 1 +
fs/proc/internal.h | 3 +++
3 files changed, 18 insertions(+)
Index: linux-2.6.git/fs/proc/array.c
===================================================================
--- linux-2.6.git.orig/fs/proc/array.c
+++ linux-2.6.git/fs/proc/array.c
@@ -547,3 +547,17 @@ int proc_pid_statm(struct seq_file *m, s
return 0;
}
+
+int proc_pid_children(struct seq_file *m, struct pid_namespace *ns,
+ struct pid *pid, struct task_struct *task)
+{
+ struct task_struct *c;
+
+ read_lock(&tasklist_lock);
+ list_for_each_entry(c, &task->children, sibling)
+ seq_printf(m, " %d", pid_nr_ns(task_pid(c), ns));
+ read_unlock(&tasklist_lock);
+ seq_putc(m, '\n');
+
+ return 0;
+}
Index: linux-2.6.git/fs/proc/base.c
===================================================================
--- linux-2.6.git.orig/fs/proc/base.c
+++ linux-2.6.git/fs/proc/base.c
@@ -3204,6 +3204,7 @@ static const struct pid_entry tgid_base_
INF("cmdline", S_IRUGO, proc_pid_cmdline),
ONE("stat", S_IRUGO, proc_tgid_stat),
ONE("statm", S_IRUGO, proc_pid_statm),
+ ONE("children", S_IRUGO, proc_pid_children),
REG("maps", S_IRUGO, proc_maps_operations),
#ifdef CONFIG_NUMA
REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
Index: linux-2.6.git/fs/proc/internal.h
===================================================================
--- linux-2.6.git.orig/fs/proc/internal.h
+++ linux-2.6.git/fs/proc/internal.h
@@ -51,6 +51,9 @@ extern int proc_pid_status(struct seq_fi
struct pid *pid, struct task_struct *task);
extern int proc_pid_statm(struct seq_file *m, struct pid_namespace *ns,
struct pid *pid, struct task_struct *task);
+extern int proc_pid_children(struct seq_file *m, struct pid_namespace *ns,
+ struct pid *pid, struct task_struct *task);
+
extern loff_t mem_lseek(struct file *file, loff_t offset, int orig);
extern const struct file_operations proc_maps_operations;

279
kernel/fs-proc-add-children-entry-11 Normal file
View File

@@ -0,0 +1,279 @@
From: Cyrill Gorcunov <gorcunov@openvz.org>
Subject: [PATCH] fs, proc: Introduce the /proc/<pid>/children entry v4
There is no easy way to make a reverse parent->children chain
from arbitrary <pid> (while parent pid is provided in "PPid"
field of /proc/<pid>/status).
So instead of walking over all pids in the system to figure out which
children a task have -- we add explicit /proc/<pid>/children entry,
because kernel already has this kind of information but it is not
yet exported. This is a first level children, not the whole process
tree, neither the process threads are identified with this interface.
v2:
- Kame suggested to use a separated /proc/<pid>/children entry
instead of poking /proc/<pid>/status
- Andew suggested to use rcu facility instead of locking
tasklist_lock
- Tejun pointed that non-seekable seq file might not be
enough for tasks with large number of children
v3:
- To be on a safe side use %lu format for pid_t printing
v4:
- New line get printed when sequence ends not at seq->stop,
a nit pointed by Tejun
- Documentation update
- tasklist_lock is back, Oleg pointed that ->children list
is actually not rcu-safe
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
---
Documentation/filesystems/proc.txt | 20 ++++
fs/proc/array.c | 163 +++++++++++++++++++++++++++++++++++++
fs/proc/base.c | 1
fs/proc/internal.h | 6 +
4 files changed, 190 insertions(+)
Index: linux-2.6.git/Documentation/filesystems/proc.txt
===================================================================
--- linux-2.6.git.orig/Documentation/filesystems/proc.txt
+++ linux-2.6.git/Documentation/filesystems/proc.txt
@@ -40,6 +40,7 @@ Table of Contents
3.4 /proc/<pid>/coredump_filter - Core dump filtering settings
3.5 /proc/<pid>/mountinfo - Information about mounts
3.6 /proc/<pid>/comm & /proc/<pid>/task/<tid>/comm
+ 3.7 /proc/<pid>/children - Information about task children
------------------------------------------------------------------------------
@@ -1545,3 +1546,22 @@ a task to set its own or one of its thre
is limited in size compared to the cmdline value, so writing anything longer
then the kernel's TASK_COMM_LEN (currently 16 chars) will result in a truncated
comm value.
+
+3.7 /proc/<pid>/children - Information about task children
+--------------------------------------------------------------
+This file provides a fast way to retrieve first level children pids
+of a task pointed by <pid>. The format is a stream of pids separated
+by space with a new line at the end. If a task has no children at
+all -- only a new line returned.
+
+Note the "first level" here -- if a child has own children they will
+not be printed there, one need to read /proc/<children-pid>/children
+to obtain descendants. The same applies to threads -- they are not
+counted here.
+
+Because this interface is intended to be fast and cheap it doesn't
+guarantee to provide the precise results, which means if a child is
+exiting it might or might not be counted. The same applies to freshly
+created children -- they might or might not be counted. If one needs
+precise pids -- the task and children should be either stopped or
+frozen.
Index: linux-2.6.git/fs/proc/array.c
===================================================================
--- linux-2.6.git.orig/fs/proc/array.c
+++ linux-2.6.git/fs/proc/array.c
@@ -547,3 +547,166 @@ int proc_pid_statm(struct seq_file *m, s
return 0;
}
+
+static struct list_head *
+children_get_at(struct proc_pid_children_iter *iter, loff_t pos)
+{
+ struct task_struct *t = iter->group_leader;
+ struct task_struct *task;
+
+ rcu_read_lock();
+ do {
+ list_for_each_entry(task, &t->children, sibling) {
+ if (list_empty(&task->sibling))
+ break;
+ if (pos-- == 0) {
+ put_task_struct(iter->last_group);
+ iter->last_group = t;
+ get_task_struct(iter->last_group);
+ get_task_struct(task);
+ rcu_read_unlock();
+ return &task->sibling;
+ }
+ }
+ } while_each_thread(iter->group_leader, t);
+ rcu_read_unlock();
+
+ return NULL;
+}
+
+static int children_seq_show(struct seq_file *seq, void *v)
+{
+ struct task_struct *task = container_of(v, struct task_struct, sibling);
+ unsigned long pid;
+ int ret = -1;
+
+ rcu_read_lock();
+ if (pid_alive(task)) {
+ pid = (unsigned long)pid_vnr(task_pid(task));
+ ret = 0;
+ }
+ rcu_read_unlock();
+
+ if (!ret)
+ ret = seq_printf(seq, " %lu", pid);
+ return ret;
+}
+
+static void *children_seq_start(struct seq_file *seq, loff_t *pos)
+{
+ return children_get_at(seq->private, *pos);
+}
+
+static void *children_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ struct proc_pid_children_iter *iter = seq->private;
+ struct task_struct *task = container_of(v, struct task_struct, sibling);
+ struct list_head *next = NULL;
+
+ if (!iter->last_group)
+ goto out;
+
+ rcu_read_lock();
+
+ if (list_empty(&task->sibling) ||
+ list_is_last(v, &iter->last_group->children)) {
+ struct task_struct *t = iter->last_group;
+
+ while_each_thread(iter->group_leader, t) {
+ if (!list_empty(&t->children)) {
+ put_task_struct(task);
+ next = t->children.next;
+ task = container_of(next, struct task_struct, sibling);
+ get_task_struct(task);
+ put_task_struct(iter->last_group);
+ iter->last_group = t;
+ get_task_struct(iter->last_group);
+ goto out_unlock;
+ }
+ }
+
+ put_task_struct(task);
+ put_task_struct(iter->last_group);
+ iter->last_group = NULL;
+ } else {
+ next = ((struct list_head *)v)->next;
+ put_task_struct(task);
+ task = container_of(next, struct task_struct, sibling);
+ get_task_struct(task);
+ }
+out_unlock:
+ rcu_read_unlock();
+out:
+ ++*pos;
+ if (!next)
+ seq_printf(seq, "\n");
+ return next;
+}
+
+static void children_seq_stop(struct seq_file *seq, void *v)
+{
+ struct proc_pid_children_iter *iter = seq->private;
+ if (iter->last_group)
+ put_task_struct(iter->last_group);
+ iter->last_group = NULL;
+}
+
+static const struct seq_operations children_seq_ops = {
+ .start = children_seq_start,
+ .next = children_seq_next,
+ .stop = children_seq_stop,
+ .show = children_seq_show,
+};
+
+static int children_seq_open(struct inode *inode, struct file *file)
+{
+ struct proc_pid_children_iter *iter = NULL;
+ struct task_struct *task = NULL;
+ int ret;
+
+ ret = -ENOMEM;
+ iter = kmalloc(sizeof(*iter), GFP_KERNEL);
+ if (!iter)
+ goto err;
+
+ ret = -ENOENT;
+ task = get_proc_task(inode);
+ if (!task)
+ goto err;
+
+ ret = seq_open(file, &children_seq_ops);
+ if (!ret) {
+ struct seq_file *m = file->private_data;
+ m->private = iter;
+ iter->group_leader = task;
+ iter->last_group = task;
+ get_task_struct(iter->last_group);
+ }
+
+err:
+ if (ret) {
+ if (task)
+ put_task_struct(task);
+ kfree(iter);
+ }
+
+ return ret;
+}
+
+int children_seq_release(struct inode *inode, struct file *file)
+{
+ struct seq_file *m = file->private_data;
+ struct proc_pid_children_iter *iter = m->private;
+
+ put_task_struct(iter->group_leader);
+ kfree(iter);
+ seq_release(inode, file);
+ return 0;
+}
+
+const struct file_operations proc_pid_children_operations = {
+ .open = children_seq_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = children_seq_release,
+};
Index: linux-2.6.git/fs/proc/base.c
===================================================================
--- linux-2.6.git.orig/fs/proc/base.c
+++ linux-2.6.git/fs/proc/base.c
@@ -3204,6 +3204,7 @@ static const struct pid_entry tgid_base_
INF("cmdline", S_IRUGO, proc_pid_cmdline),
ONE("stat", S_IRUGO, proc_tgid_stat),
ONE("statm", S_IRUGO, proc_pid_statm),
+ REG("children", S_IRUGO, proc_pid_children_operations),
REG("maps", S_IRUGO, proc_maps_operations),
#ifdef CONFIG_NUMA
REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
Index: linux-2.6.git/fs/proc/internal.h
===================================================================
--- linux-2.6.git.orig/fs/proc/internal.h
+++ linux-2.6.git/fs/proc/internal.h
@@ -53,6 +53,12 @@ extern int proc_pid_statm(struct seq_fil
struct pid *pid, struct task_struct *task);
extern loff_t mem_lseek(struct file *file, loff_t offset, int orig);
+struct proc_pid_children_iter {
+ struct task_struct *group_leader;
+ struct task_struct *last_group;
+};
+
+extern const struct file_operations proc_pid_children_operations;
extern const struct file_operations proc_maps_operations;
extern const struct file_operations proc_numa_maps_operations;
extern const struct file_operations proc_smaps_operations;

3
kernel/mincore-Add-named-constant-for-reported-present-bit
View File

@@ -1,4 +1,5 @@
mincore: Add named constant for reported present bit
From: Cyrill Gorcunov <gorcunov@openvz.org>
Subject: [PATCH] mincore: Add named constant for reported present bit
From: Pavel Emelyanov <xemul@parallels.com>

3
kernel/mincore-Report-whether-page-is-anon-or-not
View File

@@ -1,4 +1,5 @@
mincore: Report whether page is anon or not
From: Cyrill Gorcunov <gorcunov@openvz.org>
Subject: [PATCH] mincore: Report whether page is anon or not
From: Pavel Emelyanov <xemul@parallels.com>

3
kernel/procfs-introduce-the-proc-pid-map_files-directory-checkpatch
View File

@@ -1,4 +1,5 @@
procfs-introduce-the-proc-pid-map_files-directory-checkpatch-fixes
From: Cyrill Gorcunov <gorcunov@openvz.org>
Subject: [PATCH] procfs-introduce-the-proc-pid-map_files-directory-checkpatch-fixes
From: Andrew Morton <akpm@linux-foundation.org>

11
kernel/series
View File

@@ -1,9 +1,12 @@
fs-proc-Make-proc_get_link-to-use-dentry
fs-proc-Introduce-the-proc-pid-map_files-directory
procfs-introduce-the-proc-pid-map_files-directory-checkpatch
fs-proc-Add-start_data-end_data-start_brk-members
fs-proc-add-children-entry
prctl-tune-up-mm_struct-members-2
sysfs-add-kernel.ns_last_pid
c-r-introduce-checkpoint_restore-symbol.patch
c-r-procfs-add-start_data-end_data-start_brk-members-to-proc-pid-stat-v4.patch
c-r-procfs-add-start_data-end_data-start_brk-members-to-proc-pid-stat-v4-fix.patch
c-r-prctl-add-pr_set_mm-codes-to-set-up-mm_struct-entries.patch
c-r-prctl-add-pr_set_mm-codes-to-set-up-mm_struct-entries-fix.patch
mincore-Add-named-constant-for-reported-present-bit
mincore-Report-whether-page-is-anon-or-not
sysfs-add-kernel.ns_last_pid
fs-proc-add-children-entry-11

3
kernel/sysfs-add-kernel.ns_last_pid
View File

@@ -1,4 +1,5 @@
sysctl: Add the kernel.ns_last_pid control
From: Cyrill Gorcunov <gorcunov@openvz.org>
Subject: [PATCH] sysctl: Add the kernel.ns_last_pid control
From: Pavel Emelyanov <xemul@parallels.com>