[PATCH 06/14] resource limits: track highwater mark of cores dumped

[Topi Miettinen <toiwoton@gmail.com>]

Track maximum size of core dump written, to be able to configure
RLIMIT_CORE resource limits. The information is available
with taskstats and cgroupstats netlink socket.

Signed-off-by: Topi Miettinen <toiwoton@gmail.com>
---
 fs/coredump.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/fs/coredump.c b/fs/coredump.c
index 281b768..a0ace88 100644
--- a/fs/coredump.c
+++ b/fs/coredump.c
@@ -784,20 +784,25 @@ int dump_emit(struct coredump_params *cprm, const void *addr, int nr)
 	struct file *file = cprm->file;
 	loff_t pos = file->f_pos;
 	ssize_t n;
+	int r = 0;
+
 	if (cprm->written + nr > cprm->limit)
 		return 0;
 	while (nr) {
 		if (dump_interrupted())
-			return 0;
+			goto err;
 		n = __kernel_write(file, addr, nr, &pos);
 		if (n <= 0)
-			return 0;
+			goto err;
 		file->f_pos = pos;
 		cprm->written += n;
 		cprm->pos += n;
 		nr -= n;
 	}
-	return 1;
+	r = 1;
+ err:
+	update_resource_highwatermark(RLIMIT_CORE, cprm->written);
+	return r;
 }
 EXPORT_SYMBOL(dump_emit);
 
-- 
2.8.1