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>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index 12fee132fbe2..a76a26a1db8a 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -307,6 +307,9 @@ Table 1-4: Contents of the stat files (as of 2.6.30-rc7)
   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 expanded with brk()
 ..............................................................................
 
 The /proc/PID/maps file containing the currently mapped memory regions and