[Devel] [PATCH rh7 1/6] Revert "ve/devtmpfs: Create required devices on container startup"

[Vladimir Davydov]

This reverts commit 5cd1d17ff1b6a8f476ab6f4cd0a6830fbffe43f2.

We don't actually need separate null, zero, and other mem class devices
inside a VE. The patch being reverted added them merely for kdevtmpfs to
create nodes for this devices under /dev. This work can and should be
done by vzctl on container start, so drop this patch.

Signed-off-by: Vladimir Davydov <vdavydov at parallels.com>
---
 drivers/char/mem.c | 20 -------------------
 kernel/ve/ve.c     | 56 ------------------------------------------------------
 2 files changed, 76 deletions(-)

diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index c486c83be428..a3653f746a08 100644
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -30,7 +30,6 @@
 #include <linux/io.h>
 #include <linux/aio.h>
 #include <linux/security.h>
-#include <linux/ve.h>
 
 #include <asm/uaccess.h>
 
@@ -924,20 +923,7 @@ static char *mem_devnode(struct device *dev, umode_t *mode)
 	return NULL;
 }
 
-#ifdef CONFIG_VE
-static struct class mem_class_base = {
-	.name		= "mem",
-	.devnode	= mem_devnode,
-	.ns_type	= &ve_ns_type_operations,
-	.namespace	= ve_namespace,
-	.owner		= THIS_MODULE,
-};
-
-struct class *mem_class = &mem_class_base;
-EXPORT_SYMBOL(mem_class);
-#else
 static struct class *mem_class;
-#endif
 
 static int __init chr_dev_init(void)
 {
@@ -951,17 +937,11 @@ static int __init chr_dev_init(void)
 	if (register_chrdev(MEM_MAJOR, "mem", &memory_fops))
 		printk("unable to get major %d for memory devs\n", MEM_MAJOR);
 
-#ifdef CONFIG_VE
-	err = class_register(&mem_class_base);
-	if (err)
-		return err;
-#else
 	mem_class = class_create(THIS_MODULE, "mem");
 	if (IS_ERR(mem_class))
 		return PTR_ERR(mem_class);
 
 	mem_class->devnode = mem_devnode;
-#endif
 	for (minor = 1; minor < ARRAY_SIZE(devlist); minor++) {
 		if (!devlist[minor].name)
 			continue;
diff --git a/kernel/ve/ve.c b/kernel/ve/ve.c
index 64967273b21a..c5fdf382ac93 100644
--- a/kernel/ve/ve.c
+++ b/kernel/ve/ve.c
@@ -413,55 +413,6 @@ static void ve_drop_context(struct ve_struct *ve)
 	ve->init_cred = NULL;
 }
 
-static const struct {
-	unsigned int	minor;
-	char		*name;
-} ve_mem_class_devices[] = {
-	{3, "null"},
-	{5, "zero"},
-	{7, "full"},
-	{8, "random"},
-	{9, "urandom"},
-};
-
-extern struct class *mem_class;
-
-static int ve_init_mem_class(struct ve_struct *ve)
-{
-	struct device *dev;
-	dev_t devt;
-	size_t i;
-
-	for (i = 0; i < ARRAY_SIZE(ve_mem_class_devices); i++) {
-		devt = MKDEV(MEM_MAJOR, ve_mem_class_devices[i].minor);
-		dev = device_create(mem_class, NULL, devt,
-				    ve, ve_mem_class_devices[i].name);
-		if (IS_ERR(dev)) {
-			pr_err("Can't create %s (%d)\n",
-			       ve_mem_class_devices[i].name,
-			       (int)PTR_ERR(dev));
-			for (; i > 0; i--) {
-				devt = MKDEV(MEM_MAJOR, ve_mem_class_devices[i - 1].minor);
-				device_destroy_namespace(mem_class, devt, ve);
-			}
-			return PTR_ERR(dev);
-		}
-	}
-
-	return 0;
-}
-
-static void ve_mem_class_fini(struct ve_struct *ve)
-{
-	dev_t devt;
-	size_t i;
-
-	for (i = 0; i < ARRAY_SIZE(ve_mem_class_devices); i++) {
-		devt = MKDEV(MEM_MAJOR, ve_mem_class_devices[i].minor);
-		device_destroy_namespace(mem_class, devt, ve);
-	}
-}
-
 /* under ve->op_sem write-lock */
 int ve_start_container(struct ve_struct *ve)
 {
@@ -510,10 +461,6 @@ int ve_start_container(struct ve_struct *ve)
 	if (err)
 		goto err_tty_console;
 
-	err = ve_init_mem_class(ve);
-	if (err)
-		goto err_mem_class;
-
 	err = ve_hook_iterate_init(VE_SS_CHAIN, ve);
 	if (err < 0)
 		goto err_iterate;
@@ -527,8 +474,6 @@ int ve_start_container(struct ve_struct *ve)
 	return 0;
 
 err_iterate:
-	ve_mem_class_fini(ve);
-err_mem_class:
 	ve_tty_console_fini(ve);
 err_tty_console:
 	ve_unix98_pty_fini(ve);
@@ -569,7 +514,6 @@ void ve_stop_ns(struct pid_namespace *pid_ns)
 	ve_tty_console_fini(ve);
 	ve_unix98_pty_fini(ve);
 	ve_legacy_pty_fini(ve);
-	ve_mem_class_fini(ve);
 
 	ve_fini_devtmpfs(ve);
 
-- 
2.1.4