From: Marek Szyprowski <m.szyprowski@samsung.com>
Date: Wed, 25 Apr 2018 09:54:22 +0000 (+0200)
Subject: Revert "kmsg: add additional buffers support to memory class"
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=dae3e63f8b752144320c08d98b8457f100f70bcc;p=platform%2Fkernel%2Flinux-exynos.git

Revert "kmsg: add additional buffers support to memory class"

This reverts commit 62bbd37627b8fa194ae668b352d40c090d9cc6e0.
---

diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index 7d462343a4b0..6b1721f978c2 100644
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -799,6 +799,9 @@ static const struct memdev {
 	 [7] = { "full", 0666, &full_fops, 0 },
 	 [8] = { "random", 0666, &random_fops, 0 },
 	 [9] = { "urandom", 0666, &urandom_fops, 0 },
+#ifdef CONFIG_PRINTK
+	[11] = { "kmsg", 0644, &kmsg_fops, 0 },
+#endif
 };
 
 static int memory_open(struct inode *inode, struct file *filp)
@@ -808,7 +811,7 @@ static int memory_open(struct inode *inode, struct file *filp)
 
 	minor = iminor(inode);
 	if (minor >= ARRAY_SIZE(devlist))
-		return kmsg_memory_open(inode, filp);
+		return -ENXIO;
 
 	dev = &devlist[minor];
 	if (!dev->fops)
@@ -830,28 +833,16 @@ static const struct file_operations memory_fops = {
 
 static char *mem_devnode(struct device *dev, umode_t *mode)
 {
-	int minor = MINOR(dev->devt);
-
-	if (!mode)
-		goto out;
-
-	if (minor >= ARRAY_SIZE(devlist)) {
-		kmsg_mode(minor, mode);
-		goto out;
-	}
-
-	if (devlist[minor].mode)
-		*mode = devlist[minor].mode;
-out:
+	if (mode && devlist[MINOR(dev->devt)].mode)
+		*mode = devlist[MINOR(dev->devt)].mode;
 	return NULL;
 }
 
-struct class *mem_class;
+static struct class *mem_class;
 
 static int __init chr_dev_init(void)
 {
 	int minor;
-	struct device *kmsg;
 
 	if (register_chrdev(MEM_MAJOR, "mem", &memory_fops))
 		printk("unable to get major %d for memory devs\n", MEM_MAJOR);
@@ -875,10 +866,6 @@ static int __init chr_dev_init(void)
 			      NULL, devlist[minor].name);
 	}
 
-	kmsg = init_kmsg(KMSG_MINOR, 0644);
-	if (IS_ERR(kmsg))
-		return PTR_ERR(kmsg);
-
 	return tty_init();
 }
 
diff --git a/include/linux/printk.h b/include/linux/printk.h
index 4147304f394b..58b1fec40d37 100644
--- a/include/linux/printk.h
+++ b/include/linux/printk.h
@@ -417,40 +417,8 @@ do {									\
 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 #endif
 
-struct file;
-struct inode;
-
-#ifdef CONFIG_PRINTK
-
-extern struct class *mem_class;
-
-#define KMSG_MINOR	11
-
 extern const struct file_operations kmsg_fops;
 
-extern struct device *init_kmsg(int minor, umode_t mode);
-extern int kmsg_memory_open(struct inode *inode, struct file *filp);
-extern int kmsg_mode(int minor, umode_t *mode);
-
-#else
-
-static inline struct device *init_kmsg(int minor, umode_t mode)
-{
-	return NULL;
-}
-
-static inline int kmsg_memory_open(struct inode *inode, struct file *filp)
-{
-	return -ENXIO;
-}
-
-static inline int kmsg_mode(int minor, umode_t *mode)
-{
-	return -ENXIO;
-}
-
-#endif
-
 enum {
 	DUMP_PREFIX_NONE,
 	DUMP_PREFIX_ADDRESS,
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 94ae006569fb..ab82f563a0ea 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -46,8 +46,6 @@
 #include <linux/utsname.h>
 #include <linux/ctype.h>
 #include <linux/uio.h>
-#include <linux/device.h>
-#include <linux/kdev_t.h>
 
 #include <asm/uaccess.h>
 
@@ -243,7 +241,6 @@ struct log_buffer {
 	u64 next_seq;
 #ifdef CONFIG_PRINTK
 	u32 next_idx;		/* index of the next record to store */
-	int mode;		/* mode of device */
 	int minor;		/* minor representing buffer device */
 #endif
 };
@@ -286,7 +283,6 @@ static struct log_buffer log_buf = {
 	.first_idx	= 0,
 	.next_seq	= 0,
 	.next_idx	= 0,
-	.mode		= 0,
 	.minor		= 0,
 };
 
@@ -1190,45 +1186,6 @@ const struct file_operations kmsg_fops = {
 	.release = devkmsg_release,
 };
 
-/* Should be used for device registration */
-struct device *init_kmsg(int minor, umode_t mode)
-{
-	log_buf.minor = minor;
-	log_buf.mode = mode;
-	return device_create(mem_class, NULL, MKDEV(MEM_MAJOR, minor),
-			NULL, "kmsg");
-}
-
-int kmsg_memory_open(struct inode *inode, struct file *filp)
-{
-	filp->f_op = &kmsg_fops;
-
-	return kmsg_fops.open(inode, filp);
-}
-
-int kmsg_mode(int minor, umode_t *mode)
-{
-	int ret = -ENXIO;
-	struct log_buffer *log_b;
-
-	if (minor == log_buf.minor) {
-		*mode = log_buf.mode;
-		return 0;
-	}
-
-	rcu_read_lock();
-	list_for_each_entry_rcu(log_b, &log_buf.list, list) {
-		if (log_b->minor == minor) {
-			*mode = log_b->mode;
-			ret = 0;
-			break;
-		}
-	}
-	rcu_read_unlock();
-
-	return ret;
-}
-
 #ifdef CONFIG_KEXEC
 /*
  * This appends the listed symbols to /proc/vmcore