[PATCH 2/4] proc: Show namespaces IDs in /proc/pid/ns/* files

[Pavel Emelyanov <xemul@parallels.com>]

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

---
 fs/proc/namespaces.c |   12 ++++++++++++
 include/linux/mm.h   |    1 +
 2 files changed, 13 insertions(+), 0 deletions(-)

diff --git a/fs/proc/namespaces.c b/fs/proc/namespaces.c
index be177f7..48c64ab 100644
--- a/fs/proc/namespaces.c
+++ b/fs/proc/namespaces.c
@@ -27,8 +27,20 @@ static const struct proc_ns_operations *ns_entries[] = {
 #endif
 };
 
+static ssize_t proc_ns_read(struct file *file, char __user *buf,
+				      size_t len, loff_t *ppos)
+{
+	char tmp[32];
+	struct proc_inode *ei = PROC_I(file->f_dentry->d_inode);
+
+	snprintf(tmp, sizeof(tmp), "id:\t%lu\n",
+			gen_object_id(ei->ns, GEN_OBJ_ID_NS));
+	return simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp));
+}
+
 static const struct file_operations ns_file_operations = {
 	.llseek		= no_llseek,
+	.read		= proc_ns_read,
 };
 
 static struct dentry *proc_ns_instantiate(struct inode *dir,
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 80ea327..cd4d727 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1628,6 +1628,7 @@ extern void copy_user_huge_page(struct page *dst, struct page *src,
 #endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLBFS */
 
 enum {
+	GEN_OBJ_ID_NS,
 	GEN_OBJ_ID_TYPES,
 };
 
-- 
1.5.5.6