jbd2: Move jbd2-debug file to debugfs
The jbd2-debug file used to be located in /proc/sys/fs/jbd2-debug, but it
incorrectly used create_proc_entry() instead of the sysctl routines, and
no proc entry was ever created.
Instead of fixing this we might as well move the jbd2-debug file to
debugfs which would be the preferred location for this kind of tunable.
The new location is now /sys/kernel/debug/jbd2/jbd2-debug.
Signed-off-by: Jose R. Santos <jrs@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/Kconfig b/fs/Kconfig
index 613df55..6a64990 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -251,7 +251,7 @@
config JBD2_DEBUG
bool "JBD2 (ext4dev/ext4) debugging support"
- depends on JBD2
+ depends on JBD2 && DEBUG_FS
help
If you are using the ext4dev/ext4 journaled file system (or
potentially any other filesystem/device using JBD2), this option
@@ -260,10 +260,10 @@
By default, the debugging output will be turned off.
If you select Y here, then you will be able to turn on debugging
- with "echo N > /proc/sys/fs/jbd2-debug", where N is a number between
- 1 and 5. The higher the number, the more debugging output is
- generated. To turn debugging off again, do
- "echo 0 > /proc/sys/fs/jbd2-debug".
+ with "echo N > /sys/kernel/debug/jbd2/jbd2-debug", where N is a
+ number between 1 and 5. The higher the number, the more debugging
+ output is generated. To turn debugging off again, do
+ "echo 0 > /sys/kernel/debug/jbd2/jbd2-debug".
config FS_MBCACHE
# Meta block cache for Extended Attributes (ext2/ext3/ext4)
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index 8f530cc..f290cb7 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -35,6 +35,7 @@
#include <linux/kthread.h>
#include <linux/poison.h>
#include <linux/proc_fs.h>
+#include <linux/debugfs.h>
#include <asm/uaccess.h>
#include <asm/page.h>
@@ -1951,63 +1952,49 @@
}
/*
- * /proc tunables
+ * debugfs tunables
*/
#if defined(CONFIG_JBD2_DEBUG)
-int jbd2_journal_enable_debug;
+u8 jbd2_journal_enable_debug;
EXPORT_SYMBOL(jbd2_journal_enable_debug);
#endif
-#if defined(CONFIG_JBD2_DEBUG) && defined(CONFIG_PROC_FS)
+#if defined(CONFIG_JBD2_DEBUG) && defined(CONFIG_DEBUG_FS)
-static struct proc_dir_entry *proc_jbd_debug;
+#define JBD2_DEBUG_NAME "jbd2-debug"
-static int read_jbd_debug(char *page, char **start, off_t off,
- int count, int *eof, void *data)
+struct dentry *jbd2_debugfs_dir, *jbd2_debug;
+
+static void __init jbd2_create_debugfs_entry(void)
{
- int ret;
-
- ret = sprintf(page + off, "%d\n", jbd2_journal_enable_debug);
- *eof = 1;
- return ret;
+ jbd2_debugfs_dir = debugfs_create_dir("jbd2", NULL);
+ if (jbd2_debugfs_dir)
+ jbd2_debug = debugfs_create_u8(JBD2_DEBUG_NAME, S_IRUGO,
+ jbd2_debugfs_dir,
+ &jbd2_journal_enable_debug);
}
-static int write_jbd_debug(struct file *file, const char __user *buffer,
- unsigned long count, void *data)
+static void __exit jbd2_remove_debugfs_entry(void)
{
- char buf[32];
-
- if (count > ARRAY_SIZE(buf) - 1)
- count = ARRAY_SIZE(buf) - 1;
- if (copy_from_user(buf, buffer, count))
- return -EFAULT;
- buf[ARRAY_SIZE(buf) - 1] = '\0';
- jbd2_journal_enable_debug = simple_strtoul(buf, NULL, 10);
- return count;
-}
-
-#define JBD_PROC_NAME "sys/fs/jbd2-debug"
-
-static void __init create_jbd_proc_entry(void)
-{
- proc_jbd_debug = create_proc_entry(JBD_PROC_NAME, 0644, NULL);
- if (proc_jbd_debug) {
- /* Why is this so hard? */
- proc_jbd_debug->read_proc = read_jbd_debug;
- proc_jbd_debug->write_proc = write_jbd_debug;
- }
-}
-
-static void __exit jbd2_remove_jbd_proc_entry(void)
-{
- if (proc_jbd_debug)
- remove_proc_entry(JBD_PROC_NAME, NULL);
+ if (jbd2_debug)
+ debugfs_remove(jbd2_debug);
+ if (jbd2_debugfs_dir)
+ debugfs_remove(jbd2_debugfs_dir);
}
#else
-#define create_jbd_proc_entry() do {} while (0)
-#define jbd2_remove_jbd_proc_entry() do {} while (0)
+static void __init jbd2_create_debugfs_entry(void)
+{
+ do {
+ } while (0);
+}
+
+static void __exit jbd2_remove_debugfs_entry(void)
+{
+ do {
+ } while (0);
+}
#endif
@@ -2067,7 +2054,7 @@
ret = journal_init_caches();
if (ret != 0)
jbd2_journal_destroy_caches();
- create_jbd_proc_entry();
+ jbd2_create_debugfs_entry();
return ret;
}
@@ -2078,7 +2065,7 @@
if (n)
printk(KERN_EMERG "JBD: leaked %d journal_heads!\n", n);
#endif
- jbd2_remove_jbd_proc_entry();
+ jbd2_remove_debugfs_entry();
jbd2_journal_destroy_caches();
}
diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index a37aca3..260d6d7 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -57,7 +57,7 @@
* CONFIG_JBD2_DEBUG is on.
*/
#define JBD_EXPENSIVE_CHECKING
-extern int jbd2_journal_enable_debug;
+extern u8 jbd2_journal_enable_debug;
#define jbd_debug(n, f, a...) \
do { \