[Devel] [PATCH rh7] ve: device cgroup -- Implement devcgroup_seq_show_ve

[Cyrill Gorcunov]

In PCS7 cgroups are configured from user space, so there is
no longer connection from ve to device cgroup via css as
it was in PCS6. Instead we should open device cgroup explicitly.

https://jira.sw.ru/browse/PSBM-33555

Signed-off-by: Cyrill Gorcunov <gorcunov at odin.com>
CC: Vladimir Davydov <vdavydov at odin.com>
CC: Konstantin Khorenko <khorenko at odin.com>
CC: Andrey Vagin <avagin at odin.com>
---
 include/linux/device_cgroup.h |    2 +-
 kernel/ve/vecalls.c           |    2 +-
 security/device_cgroup.c      |   11 +++++++++--
 3 files changed, 11 insertions(+), 4 deletions(-)

Index: linux-pcs7.git/include/linux/device_cgroup.h
===================================================================
--- linux-pcs7.git.orig/include/linux/device_cgroup.h
+++ linux-pcs7.git/include/linux/device_cgroup.h
@@ -19,7 +19,7 @@ extern int devcgroup_device_visible(umod
 struct cgroup;
 int devcgroup_default_perms_ve(struct cgroup *cgroup);
 int devcgroup_set_perms_ve(struct cgroup *cgroup, unsigned, dev_t, unsigned);
-int devcgroup_seq_show_ve(struct cgroup *cgroup, unsigned veid, struct seq_file *m);
+int devcgroup_seq_show_ve(struct cgroup *devices_root, envid_t veid, struct seq_file *m);
 
 #else
 static inline int devcgroup_inode_permission(struct inode *inode, int mask)
Index: linux-pcs7.git/kernel/ve/vecalls.c
===================================================================
--- linux-pcs7.git.orig/kernel/ve/vecalls.c
+++ linux-pcs7.git/kernel/ve/vecalls.c
@@ -891,7 +891,7 @@ static int devperms_seq_show(struct seq_
 	if (ve_is_super(ve))
 		seq_printf(m, "%10u b 016 *:*\n%10u c 006 *:*\n", 0, 0);
 	else
-		devcgroup_seq_show_ve(ve->css.cgroup, ve->veid, m);
+		devcgroup_seq_show_ve(devices_root, ve->veid, m);
 
 	return 0;
 }
Index: linux-pcs7.git/security/device_cgroup.c
===================================================================
--- linux-pcs7.git.orig/security/device_cgroup.c
+++ linux-pcs7.git/security/device_cgroup.c
@@ -1091,10 +1091,16 @@ int devcgroup_set_perms_ve(struct cgroup
 }
 EXPORT_SYMBOL(devcgroup_set_perms_ve);
 
-int devcgroup_seq_show_ve(struct cgroup *cgroup, unsigned veid, struct seq_file *m)
+int devcgroup_seq_show_ve(struct cgroup *devices_root, envid_t veid, struct seq_file *m)
 {
-	struct dev_cgroup *devcgroup = cgroup_to_devcgroup(cgroup);
 	struct dev_exception_item *wh;
+	struct dev_cgroup *devcgroup;
+	struct cgroup *cgroup;
+
+	cgroup = ve_cgroup_open(devices_root, 0, veid);
+	if (IS_ERR(cgroup))
+		return PTR_ERR(cgroup);
+	devcgroup = cgroup_to_devcgroup(cgroup);
 
 	rcu_read_lock();
 	list_for_each_entry_rcu(wh, &devcgroup->exceptions, list) {
@@ -1118,6 +1124,7 @@ int devcgroup_seq_show_ve(struct cgroup
 	}
 	rcu_read_unlock();
 
+	cgroup_kernel_close(cgroup);
 	return 0;
 }
 EXPORT_SYMBOL(devcgroup_seq_show_ve);