UBIFS: add debugfs support
We need to have a possibility to see various UBIFS variables
and ask UBIFS to dump various information. Debugfs is what
we need.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
diff --git a/fs/ubifs/debug.c b/fs/ubifs/debug.c
index 0332a85..5684277 100644
--- a/fs/ubifs/debug.c
+++ b/fs/ubifs/debug.c
@@ -32,6 +32,7 @@
#include "ubifs.h"
#include <linux/module.h>
#include <linux/moduleparam.h>
+#include <linux/debugfs.h>
#ifdef CONFIG_UBIFS_FS_DEBUG
@@ -988,22 +989,20 @@
err = 1;
key_read(c, &dent1->key, &key);
if (keys_cmp(c, &zbr1->key, &key)) {
- dbg_err("1st entry at %d:%d has key %s", zbr1->lnum,
- zbr1->offs, DBGKEY(&key));
- dbg_err("but it should have key %s according to tnc",
- DBGKEY(&zbr1->key));
- dbg_dump_node(c, dent1);
- goto out_free;
+ ubifs_err("1st entry at %d:%d has key %s", zbr1->lnum,
+ zbr1->offs, DBGKEY(&key));
+ ubifs_err("but it should have key %s according to tnc",
+ DBGKEY(&zbr1->key)); dbg_dump_node(c, dent1);
+ goto out_free;
}
key_read(c, &dent2->key, &key);
if (keys_cmp(c, &zbr2->key, &key)) {
- dbg_err("2nd entry at %d:%d has key %s", zbr1->lnum,
- zbr1->offs, DBGKEY(&key));
- dbg_err("but it should have key %s according to tnc",
- DBGKEY(&zbr2->key));
- dbg_dump_node(c, dent2);
- goto out_free;
+ ubifs_err("2nd entry at %d:%d has key %s", zbr1->lnum,
+ zbr1->offs, DBGKEY(&key));
+ ubifs_err("but it should have key %s according to tnc",
+ DBGKEY(&zbr2->key)); dbg_dump_node(c, dent2);
+ goto out_free;
}
nlen1 = le16_to_cpu(dent1->nlen);
@@ -1015,14 +1014,14 @@
goto out_free;
}
if (cmp == 0 && nlen1 == nlen2)
- dbg_err("2 xent/dent nodes with the same name");
+ ubifs_err("2 xent/dent nodes with the same name");
else
- dbg_err("bad order of colliding key %s",
+ ubifs_err("bad order of colliding key %s",
DBGKEY(&key));
- dbg_msg("first node at %d:%d\n", zbr1->lnum, zbr1->offs);
+ ubifs_msg("first node at %d:%d\n", zbr1->lnum, zbr1->offs);
dbg_dump_node(c, dent1);
- dbg_msg("second node at %d:%d\n", zbr2->lnum, zbr2->offs);
+ ubifs_msg("second node at %d:%d\n", zbr2->lnum, zbr2->offs);
dbg_dump_node(c, dent2);
out_free:
@@ -2103,7 +2102,7 @@
fmi = kmalloc(sizeof(struct failure_mode_info), GFP_NOFS);
if (!fmi) {
- dbg_err("Failed to register failure mode - no memory");
+ ubifs_err("Failed to register failure mode - no memory");
return;
}
fmi->c = c;
@@ -2383,4 +2382,144 @@
kfree(c->dbg);
}
+/*
+ * Root directory for UBIFS stuff in debugfs. Contains sub-directories which
+ * contain the stuff specific to particular file-system mounts.
+ */
+static struct dentry *debugfs_rootdir;
+
+/**
+ * dbg_debugfs_init - initialize debugfs file-system.
+ *
+ * UBIFS uses debugfs file-system to expose various debugging knobs to
+ * user-space. This function creates "ubifs" directory in the debugfs
+ * file-system. Returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+int dbg_debugfs_init(void)
+{
+ debugfs_rootdir = debugfs_create_dir("ubifs", NULL);
+ if (IS_ERR(debugfs_rootdir)) {
+ int err = PTR_ERR(debugfs_rootdir);
+ ubifs_err("cannot create \"ubifs\" debugfs directory, "
+ "error %d\n", err);
+ return err;
+ }
+
+ return 0;
+}
+
+/**
+ * dbg_debugfs_exit - remove the "ubifs" directory from debugfs file-system.
+ */
+void dbg_debugfs_exit(void)
+{
+ debugfs_remove(debugfs_rootdir);
+}
+
+static int open_debugfs_file(struct inode *inode, struct file *file)
+{
+ file->private_data = inode->i_private;
+ return 0;
+}
+
+static ssize_t write_debugfs_file(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ struct ubifs_info *c = file->private_data;
+ struct ubifs_debug_info *d = c->dbg;
+
+ if (file->f_path.dentry == d->dump_lprops)
+ dbg_dump_lprops(c);
+ else if (file->f_path.dentry == d->dump_budg) {
+ spin_lock(&c->space_lock);
+ dbg_dump_budg(c);
+ spin_unlock(&c->space_lock);
+ } else if (file->f_path.dentry == d->dump_budg) {
+ mutex_lock(&c->tnc_mutex);
+ dbg_dump_tnc(c);
+ mutex_unlock(&c->tnc_mutex);
+ } else
+ return -EINVAL;
+
+ *ppos += count;
+ return count;
+}
+
+static const struct file_operations debugfs_fops = {
+ .open = open_debugfs_file,
+ .write = write_debugfs_file,
+ .owner = THIS_MODULE,
+};
+
+/**
+ * dbg_debugfs_init_fs - initialize debugfs for UBIFS instance.
+ * @c: UBIFS file-system description object
+ *
+ * This function creates all debugfs files for this instance of UBIFS. Returns
+ * zero in case of success and a negative error code in case of failure.
+ *
+ * Note, the only reason we have not merged this function with the
+ * 'ubifs_debugging_init()' function is because it is better to initialize
+ * debugfs interfaces at the very end of the mount process, and remove them at
+ * the very beginning of the mount process.
+ */
+int dbg_debugfs_init_fs(struct ubifs_info *c)
+{
+ int err;
+ const char *fname;
+ struct dentry *dent;
+ struct ubifs_debug_info *d = c->dbg;
+
+ sprintf(d->debugfs_dir_name, "ubi%d_%d", c->vi.ubi_num, c->vi.vol_id);
+ d->debugfs_dir = debugfs_create_dir(d->debugfs_dir_name,
+ debugfs_rootdir);
+ if (IS_ERR(d->debugfs_dir)) {
+ err = PTR_ERR(d->debugfs_dir);
+ ubifs_err("cannot create \"%s\" debugfs directory, error %d\n",
+ d->debugfs_dir_name, err);
+ goto out;
+ }
+
+ fname = "dump_lprops";
+ dent = debugfs_create_file(fname, S_IWUGO, d->debugfs_dir, c,
+ &debugfs_fops);
+ if (IS_ERR(dent))
+ goto out_remove;
+ d->dump_lprops = dent;
+
+ fname = "dump_budg";
+ dent = debugfs_create_file(fname, S_IWUGO, d->debugfs_dir, c,
+ &debugfs_fops);
+ if (IS_ERR(dent))
+ goto out_remove;
+ d->dump_budg = dent;
+
+ fname = "dump_tnc";
+ dent = debugfs_create_file(fname, S_IWUGO, d->debugfs_dir, c,
+ &debugfs_fops);
+ if (IS_ERR(dent))
+ goto out_remove;
+ d->dump_tnc = dent;
+
+ return 0;
+
+out_remove:
+ err = PTR_ERR(dent);
+ ubifs_err("cannot create \"%s\" debugfs directory, error %d\n",
+ fname, err);
+ debugfs_remove_recursive(d->debugfs_dir);
+out:
+ return err;
+}
+
+/**
+ * dbg_debugfs_exit_fs - remove all debugfs files.
+ * @c: UBIFS file-system description object
+ */
+void dbg_debugfs_exit_fs(struct ubifs_info *c)
+{
+ debugfs_remove_recursive(c->dbg->debugfs_dir);
+}
+
#endif /* CONFIG_UBIFS_FS_DEBUG */
diff --git a/fs/ubifs/debug.h b/fs/ubifs/debug.h
index d6ea136..a6b70f8 100644
--- a/fs/ubifs/debug.h
+++ b/fs/ubifs/debug.h
@@ -43,6 +43,13 @@
* @new_nhead_offs: used by LPT tree size checker
* @new_ihead_lnum: used by debugging to check ihead_lnum
* @new_ihead_offs: used by debugging to check ihead_offs
+ *
+ * debugfs_dir_name: name of debugfs directory containing this file-system's
+ * files
+ * debugfs_dir: direntry object of the file-system debugfs directory
+ * dump_lprops: "dump lprops" debugfs knob
+ * dump_budg: "dump budgeting information" debugfs knob
+ * dump_tnc: "dump TNC" debugfs knob
*/
struct ubifs_debug_info {
void *buf;
@@ -61,6 +68,12 @@
int new_nhead_offs;
int new_ihead_lnum;
int new_ihead_offs;
+
+ char debugfs_dir_name[100];
+ struct dentry *debugfs_dir;
+ struct dentry *dump_lprops;
+ struct dentry *dump_budg;
+ struct dentry *dump_tnc;
};
#define ubifs_assert(expr) do { \
@@ -251,7 +264,6 @@
void ubifs_debugging_exit(struct ubifs_info *c);
/* Dump functions */
-
const char *dbg_ntype(int type);
const char *dbg_cstate(int cmt_state);
const char *dbg_get_key_dump(const struct ubifs_info *c,
@@ -274,7 +286,6 @@
void dbg_dump_index(struct ubifs_info *c);
/* Checking helper functions */
-
typedef int (*dbg_leaf_callback)(struct ubifs_info *c,
struct ubifs_zbranch *zbr, void *priv);
typedef int (*dbg_znode_callback)(struct ubifs_info *c,
@@ -354,6 +365,12 @@
return dbg_leb_change(desc, lnum, buf, len, UBI_UNKNOWN);
}
+/* Debugfs-related stuff */
+int dbg_debugfs_init(void);
+void dbg_debugfs_exit(void);
+int dbg_debugfs_init_fs(struct ubifs_info *c);
+void dbg_debugfs_exit_fs(struct ubifs_info *c);
+
#else /* !CONFIG_UBIFS_FS_DEBUG */
/* Use "if (0)" to make compiler check arguments even if debugging is off */
@@ -434,6 +451,10 @@
#define dbg_force_in_the_gaps() 0
#define dbg_failure_mode 0
-#endif /* !CONFIG_UBIFS_FS_DEBUG */
+#define dbg_debugfs_init() 0
+#define dbg_debugfs_exit()
+#define dbg_debugfs_init_fs(c) 0
+#define dbg_debugfs_exit_fs(c) 0
+#endif /* !CONFIG_UBIFS_FS_DEBUG */
#endif /* !__UBIFS_DEBUG_H__ */
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index ad44822..2dbaa4f 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -1258,6 +1258,10 @@
}
}
+ err = dbg_debugfs_init_fs(c);
+ if (err)
+ goto out_infos;
+
err = dbg_check_filesystem(c);
if (err)
goto out_infos;
@@ -1369,6 +1373,7 @@
dbg_gen("un-mounting UBI device %d, volume %d", c->vi.ubi_num,
c->vi.vol_id);
+ dbg_debugfs_exit_fs(c);
spin_lock(&ubifs_infos_lock);
list_del(&c->infos_list);
spin_unlock(&ubifs_infos_lock);
@@ -2079,11 +2084,17 @@
err = ubifs_compressors_init();
if (err)
+ goto out_shrinker;
+
+ err = dbg_debugfs_init();
+ if (err)
goto out_compr;
return 0;
out_compr:
+ ubifs_compressors_exit();
+out_shrinker:
unregister_shrinker(&ubifs_shrinker_info);
kmem_cache_destroy(ubifs_inode_slab);
out_reg:
@@ -2098,6 +2109,7 @@
ubifs_assert(list_empty(&ubifs_infos));
ubifs_assert(atomic_long_read(&ubifs_clean_zn_cnt) == 0);
+ dbg_debugfs_exit();
ubifs_compressors_exit();
unregister_shrinker(&ubifs_shrinker_info);
kmem_cache_destroy(ubifs_inode_slab);
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index 7e090a5..4cf28e8 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -1158,6 +1158,7 @@
* @mount_opts: UBIFS-specific mount options
*
* @dbg: debugging-related information
+ * @dfs: debugfs support-related information
*/
struct ubifs_info {
struct super_block *vfs_sb;