printk: move to separate directory for easier modification

Make it easier to break up printk into bite-sized chunks.

Remove printk path/filename from comment.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Samuel Thibault <samuel.thibault@ens-lyon.org>
Cc: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 0 insertions, 2924 deletions

diff --git a/kernel/printk.c b/kernel/printk.c
deleted file mode 100644
index 69b0890ed7e5..000000000000
--- a/kernel/printk.c
+++ /dev/null
@@ -1,2924 +0,0 @@
-/*
- *  linux/kernel/printk.c
- *
- *  Copyright (C) 1991, 1992  Linus Torvalds
- *
- * Modified to make sys_syslog() more flexible: added commands to
- * return the last 4k of kernel messages, regardless of whether
- * they've been read or not.  Added option to suppress kernel printk's
- * to the console.  Added hook for sending the console messages
- * elsewhere, in preparation for a serial line console (someday).
- * Ted Ts'o, 2/11/93.
- * Modified for sysctl support, 1/8/97, Chris Horn.
- * Fixed SMP synchronization, 08/08/99, Manfred Spraul
- *     manfred@colorfullife.com
- * Rewrote bits to get rid of console_lock
- *	01Mar01 Andrew Morton
- */
-
-#include <linux/kernel.h>
-#include <linux/mm.h>
-#include <linux/tty.h>
-#include <linux/tty_driver.h>
-#include <linux/console.h>
-#include <linux/init.h>
-#include <linux/jiffies.h>
-#include <linux/nmi.h>
-#include <linux/module.h>
-#include <linux/moduleparam.h>
-#include <linux/interrupt.h>			/* For in_interrupt() */
-#include <linux/delay.h>
-#include <linux/smp.h>
-#include <linux/security.h>
-#include <linux/bootmem.h>
-#include <linux/memblock.h>
-#include <linux/aio.h>
-#include <linux/syscalls.h>
-#include <linux/kexec.h>
-#include <linux/kdb.h>
-#include <linux/ratelimit.h>
-#include <linux/kmsg_dump.h>
-#include <linux/syslog.h>
-#include <linux/cpu.h>
-#include <linux/notifier.h>
-#include <linux/rculist.h>
-#include <linux/poll.h>
-#include <linux/irq_work.h>
-#include <linux/utsname.h>
-
-#include <asm/uaccess.h>
-
-#define CREATE_TRACE_POINTS
-#include <trace/events/printk.h>
-
-/* printk's without a loglevel use this.. */
-#define DEFAULT_MESSAGE_LOGLEVEL CONFIG_DEFAULT_MESSAGE_LOGLEVEL
-
-/* We show everything that is MORE important than this.. */
-#define MINIMUM_CONSOLE_LOGLEVEL 1 /* Minimum loglevel we let people use */
-#define DEFAULT_CONSOLE_LOGLEVEL 7 /* anything MORE serious than KERN_DEBUG */
-
-int console_printk[4] = {
-	DEFAULT_CONSOLE_LOGLEVEL,	/* console_loglevel */
-	DEFAULT_MESSAGE_LOGLEVEL,	/* default_message_loglevel */
-	MINIMUM_CONSOLE_LOGLEVEL,	/* minimum_console_loglevel */
-	DEFAULT_CONSOLE_LOGLEVEL,	/* default_console_loglevel */
-};
-
-/*
- * Low level drivers may need that to know if they can schedule in
- * their unblank() callback or not. So let's export it.
- */
-int oops_in_progress;
-EXPORT_SYMBOL(oops_in_progress);
-
-/*
- * console_sem protects the console_drivers list, and also
- * provides serialisation for access to the entire console
- * driver system.
- */
-static DEFINE_SEMAPHORE(console_sem);
-struct console *console_drivers;
-EXPORT_SYMBOL_GPL(console_drivers);
-
-#ifdef CONFIG_LOCKDEP
-static struct lockdep_map console_lock_dep_map = {
-	.name = "console_lock"
-};
-#endif
-
-/*
- * This is used for debugging the mess that is the VT code by
- * keeping track if we have the console semaphore held. It's
- * definitely not the perfect debug tool (we don't know if _WE_
- * hold it are racing, but it helps tracking those weird code
- * path in the console code where we end up in places I want
- * locked without the console sempahore held
- */
-static int console_locked, console_suspended;
-
-/*
- * If exclusive_console is non-NULL then only this console is to be printed to.
- */
-static struct console *exclusive_console;
-
-/*
- *	Array of consoles built from command line options (console=)
- */
-struct console_cmdline
-{
-	char	name[8];			/* Name of the driver	    */
-	int	index;				/* Minor dev. to use	    */
-	char	*options;			/* Options for the driver   */
-#ifdef CONFIG_A11Y_BRAILLE_CONSOLE
-	char	*brl_options;			/* Options for braille driver */
-#endif
-};
-
-#define MAX_CMDLINECONSOLES 8
-
-static struct console_cmdline console_cmdline[MAX_CMDLINECONSOLES];
-static int selected_console = -1;
-static int preferred_console = -1;
-int console_set_on_cmdline;
-EXPORT_SYMBOL(console_set_on_cmdline);
-
-/* Flag: console code may call schedule() */
-static int console_may_schedule;
-
-/*
- * The printk log buffer consists of a chain of concatenated variable
- * length records. Every record starts with a record header, containing
- * the overall length of the record.
- *
- * The heads to the first and last entry in the buffer, as well as the
- * sequence numbers of these both entries are maintained when messages
- * are stored..
- *
- * If the heads indicate available messages, the length in the header
- * tells the start next message. A length == 0 for the next message
- * indicates a wrap-around to the beginning of the buffer.
- *
- * Every record carries the monotonic timestamp in microseconds, as well as
- * the standard userspace syslog level and syslog facility. The usual
- * kernel messages use LOG_KERN; userspace-injected messages always carry
- * a matching syslog facility, by default LOG_USER. The origin of every
- * message can be reliably determined that way.
- *
- * The human readable log message directly follows the message header. The
- * length of the message text is stored in the header, the stored message
- * is not terminated.
- *
- * Optionally, a message can carry a dictionary of properties (key/value pairs),
- * to provide userspace with a machine-readable message context.
- *
- * Examples for well-defined, commonly used property names are:
- *   DEVICE=b12:8               device identifier
- *                                b12:8         block dev_t
- *                                c127:3        char dev_t
- *                                n8            netdev ifindex
- *                                +sound:card0  subsystem:devname
- *   SUBSYSTEM=pci              driver-core subsystem name
- *
- * Valid characters in property names are [a-zA-Z0-9.-_]. The plain text value
- * follows directly after a '=' character. Every property is terminated by
- * a '\0' character. The last property is not terminated.
- *
- * Example of a message structure:
- *   0000  ff 8f 00 00 00 00 00 00      monotonic time in nsec
- *   0008  34 00                        record is 52 bytes long
- *   000a        0b 00                  text is 11 bytes long
- *   000c              1f 00            dictionary is 23 bytes long
- *   000e                    03 00      LOG_KERN (facility) LOG_ERR (level)
- *   0010  69 74 27 73 20 61 20 6c      "it's a l"
- *         69 6e 65                     "ine"
- *   001b           44 45 56 49 43      "DEVIC"
- *         45 3d 62 38 3a 32 00 44      "E=b8:2\0D"
- *         52 49 56 45 52 3d 62 75      "RIVER=bu"
- *         67                           "g"
- *   0032     00 00 00                  padding to next message header
- *
- * The 'struct log' buffer header must never be directly exported to
- * userspace, it is a kernel-private implementation detail that might
- * need to be changed in the future, when the requirements change.
- *
- * /dev/kmsg exports the structured data in the following line format:
- *   "level,sequnum,timestamp;<message text>\n"
- *
- * The optional key/value pairs are attached as continuation lines starting
- * with a space character and terminated by a newline. All possible
- * non-prinatable characters are escaped in the "\xff" notation.
- *
- * Users of the export format should ignore possible additional values
- * separated by ',', and find the message after the ';' character.
- */
-
-enum log_flags {
-	LOG_NOCONS	= 1,	/* already flushed, do not print to console */
-	LOG_NEWLINE	= 2,	/* text ended with a newline */
-	LOG_PREFIX	= 4,	/* text started with a prefix */
-	LOG_CONT	= 8,	/* text is a fragment of a continuation line */
-};
-
-struct log {
-	u64 ts_nsec;		/* timestamp in nanoseconds */
-	u16 len;		/* length of entire record */
-	u16 text_len;		/* length of text buffer */
-	u16 dict_len;		/* length of dictionary buffer */
-	u8 facility;		/* syslog facility */
-	u8 flags:5;		/* internal record flags */
-	u8 level:3;		/* syslog level */
-};
-
-/*
- * The logbuf_lock protects kmsg buffer, indices, counters. It is also
- * used in interesting ways to provide interlocking in console_unlock();
- */
-static DEFINE_RAW_SPINLOCK(logbuf_lock);
-
-#ifdef CONFIG_PRINTK
-DECLARE_WAIT_QUEUE_HEAD(log_wait);
-/* the next printk record to read by syslog(READ) or /proc/kmsg */
-static u64 syslog_seq;
-static u32 syslog_idx;
-static enum log_flags syslog_prev;
-static size_t syslog_partial;
-
-/* index and sequence number of the first record stored in the buffer */
-static u64 log_first_seq;
-static u32 log_first_idx;
-
-/* index and sequence number of the next record to store in the buffer */
-static u64 log_next_seq;
-static u32 log_next_idx;
-
-/* the next printk record to write to the console */
-static u64 console_seq;
-static u32 console_idx;
-static enum log_flags console_prev;
-
-/* the next printk record to read after the last 'clear' command */
-static u64 clear_seq;
-static u32 clear_idx;
-
-#define PREFIX_MAX		32
-#define LOG_LINE_MAX		1024 - PREFIX_MAX
-
-/* record buffer */
-#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
-#define LOG_ALIGN 4
-#else
-#define LOG_ALIGN __alignof__(struct log)
-#endif
-#define __LOG_BUF_LEN (1 << CONFIG_LOG_BUF_SHIFT)
-static char __log_buf[__LOG_BUF_LEN] __aligned(LOG_ALIGN);
-static char *log_buf = __log_buf;
-static u32 log_buf_len = __LOG_BUF_LEN;
-
-/* cpu currently holding logbuf_lock */
-static volatile unsigned int logbuf_cpu = UINT_MAX;
-
-/* human readable text of the record */
-static char *log_text(const struct log *msg)
-{
-	return (char *)msg + sizeof(struct log);
-}
-
-/* optional key/value pair dictionary attached to the record */
-static char *log_dict(const struct log *msg)
-{
-	return (char *)msg + sizeof(struct log) + msg->text_len;
-}
-
-/* get record by index; idx must point to valid msg */
-static struct log *log_from_idx(u32 idx)
-{
-	struct log *msg = (struct log *)(log_buf + idx);
-
-	/*
-	 * A length == 0 record is the end of buffer marker. Wrap around and
-	 * read the message at the start of the buffer.
-	 */
-	if (!msg->len)
-		return (struct log *)log_buf;
-	return msg;
-}
-
-/* get next record; idx must point to valid msg */
-static u32 log_next(u32 idx)
-{
-	struct log *msg = (struct log *)(log_buf + idx);
-
-	/* length == 0 indicates the end of the buffer; wrap */
-	/*
-	 * A length == 0 record is the end of buffer marker. Wrap around and
-	 * read the message at the start of the buffer as *this* one, and
-	 * return the one after that.
-	 */
-	if (!msg->len) {
-		msg = (struct log *)log_buf;
-		return msg->len;
-	}
-	return idx + msg->len;
-}
-
-/* insert record into the buffer, discard old ones, update heads */
-static void log_store(int facility, int level,
-		      enum log_flags flags, u64 ts_nsec,
-		      const char *dict, u16 dict_len,
-		      const char *text, u16 text_len)
-{
-	struct log *msg;
-	u32 size, pad_len;
-
-	/* number of '\0' padding bytes to next message */
-	size = sizeof(struct log) + text_len + dict_len;
-	pad_len = (-size) & (LOG_ALIGN - 1);
-	size += pad_len;
-
-	while (log_first_seq < log_next_seq) {
-		u32 free;
-
-		if (log_next_idx > log_first_idx)
-			free = max(log_buf_len - log_next_idx, log_first_idx);
-		else
-			free = log_first_idx - log_next_idx;
-
-		if (free > size + sizeof(struct log))
-			break;
-
-		/* drop old messages until we have enough contiuous space */
-		log_first_idx = log_next(log_first_idx);
-		log_first_seq++;
-	}
-
-	if (log_next_idx + size + sizeof(struct log) >= log_buf_len) {
-		/*
-		 * This message + an additional empty header does not fit
-		 * at the end of the buffer. Add an empty header with len == 0
-		 * to signify a wrap around.
-		 */
-		memset(log_buf + log_next_idx, 0, sizeof(struct log));
-		log_next_idx = 0;
-	}
-
-	/* fill message */
-	msg = (struct log *)(log_buf + log_next_idx);
-	memcpy(log_text(msg), text, text_len);
-	msg->text_len = text_len;
-	memcpy(log_dict(msg), dict, dict_len);
-	msg->dict_len = dict_len;
-	msg->facility = facility;
-	msg->level = level & 7;
-	msg->flags = flags & 0x1f;
-	if (ts_nsec > 0)
-		msg->ts_nsec = ts_nsec;
-	else
-		msg->ts_nsec = local_clock();
-	memset(log_dict(msg) + dict_len, 0, pad_len);
-	msg->len = sizeof(struct log) + text_len + dict_len + pad_len;
-
-	/* insert message */
-	log_next_idx += msg->len;
-	log_next_seq++;
-}
-
-#ifdef CONFIG_SECURITY_DMESG_RESTRICT
-int dmesg_restrict = 1;
-#else
-int dmesg_restrict;
-#endif
-
-static int syslog_action_restricted(int type)
-{
-	if (dmesg_restrict)
-		return 1;
-	/*
-	 * Unless restricted, we allow "read all" and "get buffer size"
-	 * for everybody.
-	 */
-	return type != SYSLOG_ACTION_READ_ALL &&
-	       type != SYSLOG_ACTION_SIZE_BUFFER;
-}
-
-static int check_syslog_permissions(int type, bool from_file)
-{
-	/*
-	 * If this is from /proc/kmsg and we've already opened it, then we've
-	 * already done the capabilities checks at open time.
-	 */
-	if (from_file && type != SYSLOG_ACTION_OPEN)
-		return 0;
-
-	if (syslog_action_restricted(type)) {
-		if (capable(CAP_SYSLOG))
-			return 0;
-		/*
-		 * For historical reasons, accept CAP_SYS_ADMIN too, with
-		 * a warning.
-		 */
-		if (capable(CAP_SYS_ADMIN)) {
-			pr_warn_once("%s (%d): Attempt to access syslog with "
-				     "CAP_SYS_ADMIN but no CAP_SYSLOG "
-				     "(deprecated).\n",
-				 current->comm, task_pid_nr(current));
-			return 0;
-		}
-		return -EPERM;
-	}
-	return security_syslog(type);
-}
-
-
-/* /dev/kmsg - userspace message inject/listen interface */
-struct devkmsg_user {
-	u64 seq;
-	u32 idx;
-	enum log_flags prev;
-	struct mutex lock;
-	char buf[8192];
-};
-
-static ssize_t devkmsg_writev(struct kiocb *iocb, const struct iovec *iv,
-			      unsigned long count, loff_t pos)
-{
-	char *buf, *line;
-	int i;
-	int level = default_message_loglevel;
-	int facility = 1;	/* LOG_USER */
-	size_t len = iov_length(iv, count);
-	ssize_t ret = len;
-
-	if (len > LOG_LINE_MAX)
-		return -EINVAL;
-	buf = kmalloc(len+1, GFP_KERNEL);
-	if (buf == NULL)
-		return -ENOMEM;
-
-	line = buf;
-	for (i = 0; i < count; i++) {
-		if (copy_from_user(line, iv[i].iov_base, iv[i].iov_len)) {
-			ret = -EFAULT;
-			goto out;
-		}
-		line += iv[i].iov_len;
-	}
-
-	/*
-	 * Extract and skip the syslog prefix <[0-9]*>. Coming from userspace
-	 * the decimal value represents 32bit, the lower 3 bit are the log
-	 * level, the rest are the log facility.
-	 *
-	 * If no prefix or no userspace facility is specified, we
-	 * enforce LOG_USER, to be able to reliably distinguish
-	 * kernel-generated messages from userspace-injected ones.
-	 */
-	line = buf;
-	if (line[0] == '<') {
-		char *endp = NULL;
-
-		i = simple_strtoul(line+1, &endp, 10);
-		if (endp && endp[0] == '>') {
-			level = i & 7;
-			if (i >> 3)
-				facility = i >> 3;
-			endp++;
-			len -= endp - line;
-			line = endp;
-		}
-	}
-	line[len] = '\0';
-
-	printk_emit(facility, level, NULL, 0, "%s", line);
-out:
-	kfree(buf);
-	return ret;
-}
-
-static ssize_t devkmsg_read(struct file *file, char __user *buf,
-			    size_t count, loff_t *ppos)
-{
-	struct devkmsg_user *user = file->private_data;
-	struct log *msg;
-	u64 ts_usec;
-	size_t i;
-	char cont = '-';
-	size_t len;
-	ssize_t ret;
-
-	if (!user)
-		return -EBADF;
-
-	ret = mutex_lock_interruptible(&user->lock);
-	if (ret)
-		return ret;
-	raw_spin_lock_irq(&logbuf_lock);
-	while (user->seq == log_next_seq) {
-		if (file->f_flags & O_NONBLOCK) {
-			ret = -EAGAIN;
-			raw_spin_unlock_irq(&logbuf_lock);
-			goto out;
-		}
-
-		raw_spin_unlock_irq(&logbuf_lock);
-		ret = wait_event_interruptible(log_wait,
-					       user->seq != log_next_seq);
-		if (ret)
-			goto out;
-		raw_spin_lock_irq(&logbuf_lock);
-	}
-
-	if (user->seq < log_first_seq) {
-		/* our last seen message is gone, return error and reset */
-		user->idx = log_first_idx;
-		user->seq = log_first_seq;
-		ret = -EPIPE;
-		raw_spin_unlock_irq(&logbuf_lock);
-		goto out;
-	}
-
-	msg = log_from_idx(user->idx);
-	ts_usec = msg->ts_nsec;
-	do_div(ts_usec, 1000);
-
-	/*
-	 * If we couldn't merge continuation line fragments during the print,
-	 * export the stored flags to allow an optional external merge of the
-	 * records. Merging the records isn't always neccessarily correct, like
-	 * when we hit a race during printing. In most cases though, it produces
-	 * better readable output. 'c' in the record flags mark the first
-	 * fragment of a line, '+' the following.
-	 */
-	if (msg->flags & LOG_CONT && !(user->prev & LOG_CONT))
-		cont = 'c';
-	else if ((msg->flags & LOG_CONT) ||
-		 ((user->prev & LOG_CONT) && !(msg->flags & LOG_PREFIX)))
-		cont = '+';
-
-	len = sprintf(user->buf, "%u,%llu,%llu,%c;",
-		      (msg->facility << 3) | msg->level,
-		      user->seq, ts_usec, cont);
-	user->prev = msg->flags;
-
-	/* escape non-printable characters */
-	for (i = 0; i < msg->text_len; i++) {
-		unsigned char c = log_text(msg)[i];
-
-		if (c < ' ' || c >= 127 || c == '\\')
-			len += sprintf(user->buf + len, "\\x%02x", c);
-		else
-			user->buf[len++] = c;
-	}
-	user->buf[len++] = '\n';
-
-	if (msg->dict_len) {
-		bool line = true;
-
-		for (i = 0; i < msg->dict_len; i++) {
-			unsigned char c = log_dict(msg)[i];
-
-			if (line) {
-				user->buf[len++] = ' ';
-				line = false;
-			}
-
-			if (c == '\0') {
-				user->buf[len++] = '\n';
-				line = true;
-				continue;
-			}
-
-			if (c < ' ' || c >= 127 || c == '\\') {
-				len += sprintf(user->buf + len, "\\x%02x", c);
-				continue;
-			}
-
-			user->buf[len++] = c;
-		}
-		user->buf[len++] = '\n';
-	}
-
-	user->idx = log_next(user->idx);
-	user->seq++;
-	raw_spin_unlock_irq(&logbuf_lock);
-
-	if (len > count) {
-		ret = -EINVAL;
-		goto out;
-	}
-
-	if (copy_to_user(buf, user->buf, len)) {
-		ret = -EFAULT;
-		goto out;
-	}
-	ret = len;
-out:
-	mutex_unlock(&user->lock);
-	return ret;
-}
-
-static loff_t devkmsg_llseek(struct file *file, loff_t offset, int whence)
-{
-	struct devkmsg_user *user = file->private_data;
-	loff_t ret = 0;
-
-	if (!user)
-		return -EBADF;
-	if (offset)
-		return -ESPIPE;
-
-	raw_spin_lock_irq(&logbuf_lock);
-	switch (whence) {
-	case SEEK_SET:
-		/* the first record */
-		user->idx = log_first_idx;
-		user->seq = log_first_seq;
-		break;
-	case SEEK_DATA:
-		/*
-		 * The first record after the last SYSLOG_ACTION_CLEAR,
-		 * like issued by 'dmesg -c'. Reading /dev/kmsg itself
-		 * changes no global state, and does not clear anything.
-		 */
-		user->idx = clear_idx;
-		user->seq = clear_seq;
-		break;
-	case SEEK_END:
-		/* after the last record */
-		user->idx = log_next_idx;
-		user->seq = log_next_seq;
-		break;
-	default:
-		ret = -EINVAL;
-	}
-	raw_spin_unlock_irq(&logbuf_lock);
-	return ret;
-}
-
-static unsigned int devkmsg_poll(struct file *file, poll_table *wait)
-{
-	struct devkmsg_user *user = file->private_data;
-	int ret = 0;
-
-	if (!user)
-		return POLLERR|POLLNVAL;
-
-	poll_wait(file, &log_wait, wait);
-
-	raw_spin_lock_irq(&logbuf_lock);
-	if (user->seq < log_next_seq) {
-		/* return error when data has vanished underneath us */
-		if (user->seq < log_first_seq)
-			ret = POLLIN|POLLRDNORM|POLLERR|POLLPRI;
-		else
-			ret = POLLIN|POLLRDNORM;
-	}
-	raw_spin_unlock_irq(&logbuf_lock);
-
-	return ret;
-}
-
-static int devkmsg_open(struct inode *inode, struct file *file)
-{
-	struct devkmsg_user *user;
-	int err;
-
-	/* write-only does not need any file context */
-	if ((file->f_flags & O_ACCMODE) == O_WRONLY)
-		return 0;
-
-	err = check_syslog_permissions(SYSLOG_ACTION_READ_ALL,
-				       SYSLOG_FROM_READER);
-	if (err)
-		return err;
-
-	user = kmalloc(sizeof(struct devkmsg_user), GFP_KERNEL);
-	if (!user)
-		return -ENOMEM;
-
-	mutex_init(&user->lock);
-
-	raw_spin_lock_irq(&logbuf_lock);
-	user->idx = log_first_idx;
-	user->seq = log_first_seq;
-	raw_spin_unlock_irq(&logbuf_lock);
-
-	file->private_data = user;
-	return 0;
-}
-
-static int devkmsg_release(struct inode *inode, struct file *file)
-{
-	struct devkmsg_user *user = file->private_data;
-
-	if (!user)
-		return 0;
-
-	mutex_destroy(&user->lock);
-	kfree(user);
-	return 0;
-}
-
-const struct file_operations kmsg_fops = {
-	.open = devkmsg_open,
-	.read = devkmsg_read,
-	.aio_write = devkmsg_writev,
-	.llseek = devkmsg_llseek,
-	.poll = devkmsg_poll,
-	.release = devkmsg_release,
-};
-
-#ifdef CONFIG_KEXEC
-/*
- * This appends the listed symbols to /proc/vmcoreinfo
- *
- * /proc/vmcoreinfo is used by various utiilties, like crash and makedumpfile to
- * obtain access to symbols that are otherwise very difficult to locate.  These
- * symbols are specifically used so that utilities can access and extract the
- * dmesg log from a vmcore file after a crash.
- */
-void log_buf_kexec_setup(void)
-{
-	VMCOREINFO_SYMBOL(log_buf);
-	VMCOREINFO_SYMBOL(log_buf_len);
-	VMCOREINFO_SYMBOL(log_first_idx);
-	VMCOREINFO_SYMBOL(log_next_idx);
-	/*
-	 * Export struct log size and field offsets. User space tools can
-	 * parse it and detect any changes to structure down the line.
-	 */
-	VMCOREINFO_STRUCT_SIZE(log);
-	VMCOREINFO_OFFSET(log, ts_nsec);
-	VMCOREINFO_OFFSET(log, len);
-	VMCOREINFO_OFFSET(log, text_len);
-	VMCOREINFO_OFFSET(log, dict_len);
-}
-#endif
-
-/* requested log_buf_len from kernel cmdline */
-static unsigned long __initdata new_log_buf_len;
-
-/* save requested log_buf_len since it's too early to process it */
-static int __init log_buf_len_setup(char *str)
-{
-	unsigned size = memparse(str, &str);
-
-	if (size)
-		size = roundup_pow_of_two(size);
-	if (size > log_buf_len)
-		new_log_buf_len = size;
-
-	return 0;
-}
-early_param("log_buf_len", log_buf_len_setup);
-
-void __init setup_log_buf(int early)
-{
-	unsigned long flags;
-	char *new_log_buf;
-	int free;
-
-	if (!new_log_buf_len)
-		return;
-
-	if (early) {
-		unsigned long mem;
-
-		mem = memblock_alloc(new_log_buf_len, PAGE_SIZE);
-		if (!mem)
-			return;
-		new_log_buf = __va(mem);
-	} else {
-		new_log_buf = alloc_bootmem_nopanic(new_log_buf_len);
-	}
-
-	if (unlikely(!new_log_buf)) {
-		pr_err("log_buf_len: %ld bytes not available\n",
-			new_log_buf_len);
-		return;
-	}
-
-	raw_spin_lock_irqsave(&logbuf_lock, flags);
-	log_buf_len = new_log_buf_len;
-	log_buf = new_log_buf;
-	new_log_buf_len = 0;
-	free = __LOG_BUF_LEN - log_next_idx;
-	memcpy(log_buf, __log_buf, __LOG_BUF_LEN);
-	raw_spin_unlock_irqrestore(&logbuf_lock, flags);
-
-	pr_info("log_buf_len: %d\n", log_buf_len);
-	pr_info("early log buf free: %d(%d%%)\n",
-		free, (free * 100) / __LOG_BUF_LEN);
-}
-
-static bool __read_mostly ignore_loglevel;
-
-static int __init ignore_loglevel_setup(char *str)
-{
-	ignore_loglevel = 1;
-	printk(KERN_INFO "debug: ignoring loglevel setting.\n");
-
-	return 0;
-}
-
-early_param("ignore_loglevel", ignore_loglevel_setup);
-module_param(ignore_loglevel, bool, S_IRUGO | S_IWUSR);
-MODULE_PARM_DESC(ignore_loglevel, "ignore loglevel setting, to"
-	"print all kernel messages to the console.");
-
-#ifdef CONFIG_BOOT_PRINTK_DELAY
-
-static int boot_delay; /* msecs delay after each printk during bootup */
-static unsigned long long loops_per_msec;	/* based on boot_delay */
-
-static int __init boot_delay_setup(char *str)
-{
-	unsigned long lpj;
-
-	lpj = preset_lpj ? preset_lpj : 1000000;	/* some guess */
-	loops_per_msec = (unsigned long long)lpj / 1000 * HZ;
-
-	get_option(&str, &boot_delay);
-	if (boot_delay > 10 * 1000)
-		boot_delay = 0;
-
-	pr_debug("boot_delay: %u, preset_lpj: %ld, lpj: %lu, "
-		"HZ: %d, loops_per_msec: %llu\n",
-		boot_delay, preset_lpj, lpj, HZ, loops_per_msec);
-	return 1;
-}
-__setup("boot_delay=", boot_delay_setup);
-
-static void boot_delay_msec(int level)
-{
-	unsigned long long k;
-	unsigned long timeout;
-
-	if ((boot_delay == 0 || system_state != SYSTEM_BOOTING)
-		|| (level >= console_loglevel && !ignore_loglevel)) {
-		return;
-	}
-
-	k = (unsigned long long)loops_per_msec * boot_delay;
-
-	timeout = jiffies + msecs_to_jiffies(boot_delay);
-	while (k) {
-		k--;
-		cpu_relax();
-		/*
-		 * use (volatile) jiffies to prevent
-		 * compiler reduction; loop termination via jiffies
-		 * is secondary and may or may not happen.
-		 */
-		if (time_after(jiffies, timeout))
-			break;
-		touch_nmi_watchdog();
-	}
-}
-#else
-static inline void boot_delay_msec(int level)
-{
-}
-#endif
-
-#if defined(CONFIG_PRINTK_TIME)
-static bool printk_time = 1;
-#else
-static bool printk_time;
-#endif
-module_param_named(time, printk_time, bool, S_IRUGO | S_IWUSR);
-
-static size_t print_time(u64 ts, char *buf)
-{
-	unsigned long rem_nsec;
-
-	if (!printk_time)
-		return 0;
-
-	rem_nsec = do_div(ts, 1000000000);
-
-	if (!buf)
-		return snprintf(NULL, 0, "[%5lu.000000] ", (unsigned long)ts);
-
-	return sprintf(buf, "[%5lu.%06lu] ",
-		       (unsigned long)ts, rem_nsec / 1000);
-}
-
-static size_t print_prefix(const struct log *msg, bool syslog, char *buf)
-{
-	size_t len = 0;
-	unsigned int prefix = (msg->facility << 3) | msg->level;
-
-	if (syslog) {
-		if (buf) {
-			len += sprintf(buf, "<%u>", prefix);
-		} else {
-			len += 3;
-			if (prefix > 999)
-				len += 3;
-			else if (prefix > 99)
-				len += 2;
-			else if (prefix > 9)
-				len++;
-		}
-	}
-
-	len += print_time(msg->ts_nsec, buf ? buf + len : NULL);
-	return len;
-}
-
-static size_t msg_print_text(const struct log *msg, enum log_flags prev,
-			     bool syslog, char *buf, size_t size)
-{
-	const char *text = log_text(msg);
-	size_t text_size = msg->text_len;
-	bool prefix = true;
-	bool newline = true;
-	size_t len = 0;
-
-	if ((prev & LOG_CONT) && !(msg->flags & LOG_PREFIX))
-		prefix = false;
-
-	if (msg->flags & LOG_CONT) {
-		if ((prev & LOG_CONT) && !(prev & LOG_NEWLINE))
-			prefix = false;
-
-		if (!(msg->flags & LOG_NEWLINE))
-			newline = false;
-	}
-
-	do {
-		const char *next = memchr(text, '\n', text_size);
-		size_t text_len;
-
-		if (next) {
-			text_len = next - text;
-			next++;
-			text_size -= next - text;
-		} else {
-			text_len = text_size;
-		}
-
-		if (buf) {
-			if (print_prefix(msg, syslog, NULL) +
-			    text_len + 1 >= size - len)
-				break;
-
-			if (prefix)
-				len += print_prefix(msg, syslog, buf + len);
-			memcpy(buf + len, text, text_len);
-			len += text_len;
-			if (next || newline)
-				buf[len++] = '\n';
-		} else {
-			/* SYSLOG_ACTION_* buffer size only calculation */
-			if (prefix)
-				len += print_prefix(msg, syslog, NULL);
-			len += text_len;
-			if (next || newline)
-				len++;
-		}
-
-		prefix = true;
-		text = next;
-	} while (text);
-
-	return len;
-}
-
-static int syslog_print(char __user *buf, int size)
-{
-	char *text;
-	struct log *msg;
-	int len = 0;
-
-	text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL);
-	if (!text)
-		return -ENOMEM;
-
-	while (size > 0) {
-		size_t n;
-		size_t skip;
-
-		raw_spin_lock_irq(&logbuf_lock);
-		if (syslog_seq < log_first_seq) {
-			/* messages are gone, move to first one */
-			syslog_seq = log_first_seq;
-			syslog_idx = log_first_idx;
-			syslog_prev = 0;
-			syslog_partial = 0;
-		}
-		if (syslog_seq == log_next_seq) {
-			raw_spin_unlock_irq(&logbuf_lock);
-			break;
-		}
-
-		skip = syslog_partial;
-		msg = log_from_idx(syslog_idx);
-		n = msg_print_text(msg, syslog_prev, true, text,
-				   LOG_LINE_MAX + PREFIX_MAX);
-		if (n - syslog_partial <= size) {
-			/* message fits into buffer, move forward */
-			syslog_idx = log_next(syslog_idx);
-			syslog_seq++;
-			syslog_prev = msg->flags;
-			n -= syslog_partial;
-			syslog_partial = 0;
-		} else if (!len){
-			/* partial read(), remember position */
-			n = size;
-			syslog_partial += n;
-		} else
-			n = 0;
-		raw_spin_unlock_irq(&logbuf_lock);
-
-		if (!n)
-			break;
-
-		if (copy_to_user(buf, text + skip, n)) {
-			if (!len)
-				len = -EFAULT;
-			break;
-		}
-
-		len += n;
-		size -= n;
-		buf += n;
-	}
-
-	kfree(text);
-	return len;
-}
-
-static int syslog_print_all(char __user *buf, int size, bool clear)
-{
-	char *text;
-	int len = 0;
-
-	text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL);
-	if (!text)
-		return -ENOMEM;
-
-	raw_spin_lock_irq(&logbuf_lock);
-	if (buf) {
-		u64 next_seq;
-		u64 seq;
-		u32 idx;
-		enum log_flags prev;
-
-		if (clear_seq < log_first_seq) {
-			/* messages are gone, move to first available one */
-			clear_seq = log_first_seq;
-			clear_idx = log_first_idx;
-		}
-
-		/*
-		 * Find first record that fits, including all following records,
-		 * into the user-provided buffer for this dump.
-		 */
-		seq = clear_seq;
-		idx = clear_idx;
-		prev = 0;
-		while (seq < log_next_seq) {
-			struct log *msg = log_from_idx(idx);
-
-			len += msg_print_text(msg, prev, true, NULL, 0);
-			prev = msg->flags;
-			idx = log_next(idx);
-			seq++;
-		}
-
-		/* move first record forward until length fits into the buffer */
-		seq = clear_seq;
-		idx = clear_idx;
-		prev = 0;
-		while (len > size && seq < log_next_seq) {
-			struct log *msg = log_from_idx(idx);
-
-			len -= msg_print_text(msg, prev, true, NULL, 0);
-			prev = msg->flags;
-			idx = log_next(idx);
-			seq++;
-		}
-
-		/* last message fitting into this dump */
-		next_seq = log_next_seq;
-
-		len = 0;
-		prev = 0;
-		while (len >= 0 && seq < next_seq) {
-			struct log *msg = log_from_idx(idx);
-			int textlen;
-
-			textlen = msg_print_text(msg, prev, true, text,
-						 LOG_LINE_MAX + PREFIX_MAX);
-			if (textlen < 0) {
-				len = textlen;
-				break;
-			}
-			idx = log_next(idx);
-			seq++;
-			prev = msg->flags;
-
-			raw_spin_unlock_irq(&logbuf_lock);
-			if (copy_to_user(buf + len, text, textlen))
-				len = -EFAULT;
-			else
-				len += textlen;
-			raw_spin_lock_irq(&logbuf_lock);
-
-			if (seq < log_first_seq) {
-				/* messages are gone, move to next one */
-				seq = log_first_seq;
-				idx = log_first_idx;
-				prev = 0;
-			}
-		}
-	}
-
-	if (clear) {
-		clear_seq = log_next_seq;
-		clear_idx = log_next_idx;
-	}
-	raw_spin_unlock_irq(&logbuf_lock);
-
-	kfree(text);
-	return len;
-}
-
-int do_syslog(int type, char __user *buf, int len, bool from_file)
-{
-	bool clear = false;
-	static int saved_console_loglevel = -1;
-	int error;
-
-	error = check_syslog_permissions(type, from_file);
-	if (error)
-		goto out;
-
-	error = security_syslog(type);
-	if (error)
-		return error;
-
-	switch (type) {
-	case SYSLOG_ACTION_CLOSE:	/* Close log */
-		break;
-	case SYSLOG_ACTION_OPEN:	/* Open log */
-		break;
-	case SYSLOG_ACTION_READ:	/* Read from log */
-		error = -EINVAL;