[PATCH v6] mtd: create per-device and module-scope debugfs entries
Mario J. Rugiero
mrugiero at gmail.com
Mon May 22 11:56:13 PDT 2017
Several MTD devices are using debugfs entries created in the root.
This commit provides the means for a standardized subtree, creating
one "mtd" entry at root, and one entry per device inside it, named
after the device.
Devices docg3, mtdswap and nandsim were updated to use this subtree
instead of custom ones, and related cleanup to these was performed.
Signed-off-by: Mario J. Rugiero <mrugiero at gmail.com>
---
v6: - as per bbrezillon suggestion, more cleanups were done in the drivers,
removing now unused structure members and functions.
- dropped explicit setting to NULL to the dfs_dir member for the MTD,
as it is expected to be zeroed out, thanks again to bbrezillon for
pointing this out.
- removed an extern declaration of a symbol which was never defined,
spotted by bbrezillon.
v5: - cleanup drivers creating their own debugfs sub-tree.
- separate the patch again, as it makes sense on its own as cleanup.
v4: - include in a bigger patchset which explains the use of this tree.
v3: - move the changelog out of the commit message
v2: - remove unused macros and add a commit message
v1: - create the debugfs entries
drivers/mtd/devices/docg3.c | 49 ++++++++++++++++-----------------------------
drivers/mtd/devices/docg3.h | 1 -
drivers/mtd/mtdcore.c | 16 +++++++++++++++
drivers/mtd/mtdswap.c | 16 +++------------
drivers/mtd/nand/nandsim.c | 39 +++++-------------------------------
include/linux/mtd/mtd.h | 10 +++++++++
6 files changed, 51 insertions(+), 80 deletions(-)
diff --git a/drivers/mtd/devices/docg3.c b/drivers/mtd/devices/docg3.c
index b833e6cc684c..02c40a211b65 100644
--- a/drivers/mtd/devices/docg3.c
+++ b/drivers/mtd/devices/docg3.c
@@ -1809,37 +1809,22 @@ static int dbg_protection_show(struct seq_file *s, void *p)
}
DEBUGFS_RO_ATTR(protection, dbg_protection_show);
-static int __init doc_dbg_register(struct docg3 *docg3)
-{
- struct dentry *root, *entry;
-
- root = debugfs_create_dir("docg3", NULL);
- if (!root)
- return -ENOMEM;
-
- entry = debugfs_create_file("flashcontrol", S_IRUSR, root, docg3,
- &flashcontrol_fops);
- if (entry)
- entry = debugfs_create_file("asic_mode", S_IRUSR, root,
- docg3, &asic_mode_fops);
- if (entry)
- entry = debugfs_create_file("device_id", S_IRUSR, root,
- docg3, &device_id_fops);
- if (entry)
- entry = debugfs_create_file("protection", S_IRUSR, root,
- docg3, &protection_fops);
- if (entry) {
- docg3->debugfs_root = root;
- return 0;
- } else {
- debugfs_remove_recursive(root);
- return -ENOMEM;
- }
-}
-
-static void doc_dbg_unregister(struct docg3 *docg3)
+static void __init doc_dbg_register(struct mtd_info *floor)
{
- debugfs_remove_recursive(docg3->debugfs_root);
+ struct dentry *root = floor->dbg.dfs_dir;
+ struct docg3 *docg3 = floor->priv;
+
+ if (IS_ERR_OR_NULL(root))
+ return;
+
+ debugfs_create_file("flashcontrol", S_IRUSR, root, docg3,
+ &flashcontrol_fops);
+ debugfs_create_file("asic_mode", S_IRUSR, root, docg3,
+ &asic_mode_fops);
+ debugfs_create_file("device_id", S_IRUSR, root, docg3,
+ &device_id_fops);
+ debugfs_create_file("protection", S_IRUSR, root, docg3,
+ &protection_fops);
}
/**
@@ -2114,6 +2099,8 @@ static int __init docg3_probe(struct platform_device *pdev)
0);
if (ret)
goto err_probe;
+
+ doc_dbg_register(cascade->floors[floor]);
}
ret = doc_register_sysfs(pdev, cascade);
@@ -2121,7 +2108,6 @@ static int __init docg3_probe(struct platform_device *pdev)
goto err_probe;
platform_set_drvdata(pdev, cascade);
- doc_dbg_register(cascade->floors[0]->priv);
return 0;
notfound:
@@ -2148,7 +2134,6 @@ static int docg3_release(struct platform_device *pdev)
int floor;
doc_unregister_sysfs(pdev, cascade);
- doc_dbg_unregister(docg3);
for (floor = 0; floor < DOC_MAX_NBFLOORS; floor++)
if (cascade->floors[floor])
doc_release_device(cascade->floors[floor]);
diff --git a/drivers/mtd/devices/docg3.h b/drivers/mtd/devices/docg3.h
index 19fb93f96a3a..f3055907de3e 100644
--- a/drivers/mtd/devices/docg3.h
+++ b/drivers/mtd/devices/docg3.h
@@ -312,7 +312,6 @@ struct docg3 {
loff_t oob_write_ofs;
int oob_autoecc;
u8 oob_write_buf[DOC_LAYOUT_OOB_SIZE];
- struct dentry *debugfs_root;
};
#define doc_err(fmt, arg...) dev_err(docg3->dev, (fmt), ## arg)
diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
index 1517da3ddd7d..ac5feb1b96e1 100644
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -40,6 +40,7 @@
#include <linux/slab.h>
#include <linux/reboot.h>
#include <linux/leds.h>
+#include <linux/debugfs.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
@@ -662,6 +663,8 @@ static void mtd_set_dev_defaults(struct mtd_info *mtd)
}
}
+static struct dentry *dfs_dir_mtd;
+
/**
* mtd_device_parse_register - parse partitions and register an MTD device.
*
@@ -737,6 +740,14 @@ int mtd_device_parse_register(struct mtd_info *mtd, const char * const *types,
register_reboot_notifier(&mtd->reboot_notifier);
}
+ if (!IS_ERR_OR_NULL(dfs_dir_mtd)) {
+ mtd->dbg.dfs_dir = debugfs_create_dir(mtd->name, dfs_dir_mtd);
+ if (IS_ERR_OR_NULL(mtd->dbg.dfs_dir)) {
+ pr_debug("mtd device %s won't show data in debugfs\n",
+ mtd->name);
+ }
+ }
+
out:
/* Cleanup any parsed partitions */
mtd_part_parser_cleanup(&parsed);
@@ -754,6 +765,8 @@ int mtd_device_unregister(struct mtd_info *master)
{
int err;
+ debugfs_remove_recursive(master->dbg.dfs_dir);
+
if (master->_reboot)
unregister_reboot_notifier(&master->reboot_notifier);
@@ -1811,6 +1824,8 @@ static int __init init_mtd(void)
if (ret)
goto out_procfs;
+ dfs_dir_mtd = debugfs_create_dir("mtd", NULL);
+
return 0;
out_procfs:
@@ -1826,6 +1841,7 @@ static int __init init_mtd(void)
static void __exit cleanup_mtd(void)
{
+ debugfs_remove_recursive(dfs_dir_mtd);
cleanup_mtdchar();
if (proc_mtd)
remove_proc_entry("mtd", NULL);
diff --git a/drivers/mtd/mtdswap.c b/drivers/mtd/mtdswap.c
index f12879a3d4ff..ea46e52a6155 100644
--- a/drivers/mtd/mtdswap.c
+++ b/drivers/mtd/mtdswap.c
@@ -138,8 +138,6 @@ struct mtdswap_dev {
char *page_buf;
char *oob_buf;
-
- struct dentry *debugfs_root;
};
struct mtdswap_oobdata {
@@ -1318,26 +1316,19 @@ static int mtdswap_add_debugfs(struct mtdswap_dev *d)
struct gendisk *gd = d->mbd_dev->disk;
struct device *dev = disk_to_dev(gd);
- struct dentry *root;
+ struct dentry *root = d->mtd->dbg.dfs_dir;
struct dentry *dent;
- root = debugfs_create_dir(gd->disk_name, NULL);
- if (IS_ERR(root))
+ if (!IS_ENABLED(CONFIG_DEBUGFS))
return 0;
- if (!root) {
- dev_err(dev, "failed to initialize debugfs\n");
+ if (IS_ERR_OR_NULL(root))
return -1;
- }
-
- d->debugfs_root = root;
dent = debugfs_create_file("stats", S_IRUSR, root, d,
&mtdswap_fops);
if (!dent) {
dev_err(d->dev, "debugfs_create_file failed\n");
- debugfs_remove_recursive(root);
- d->debugfs_root = NULL;
return -1;
}
@@ -1540,7 +1531,6 @@ static void mtdswap_remove_dev(struct mtd_blktrans_dev *dev)
{
struct mtdswap_dev *d = MTDSWAP_MBD_TO_MTDSWAP(dev);
- debugfs_remove_recursive(d->debugfs_root);
del_mtd_blktrans_dev(dev);
mtdswap_cleanup(d);
kfree(d);
diff --git a/drivers/mtd/nand/nandsim.c b/drivers/mtd/nand/nandsim.c
index 03a0d057bf2f..357f6d914a5a 100644
--- a/drivers/mtd/nand/nandsim.c
+++ b/drivers/mtd/nand/nandsim.c
@@ -287,11 +287,6 @@ MODULE_PARM_DESC(bch, "Enable BCH ecc and set how many bits should "
/* Maximum page cache pages needed to read or write a NAND page to the cache_file */
#define NS_MAX_HELD_PAGES 16
-struct nandsim_debug_info {
- struct dentry *dfs_root;
- struct dentry *dfs_wear_report;
-};
-
/*
* A union to represent flash memory contents and flash buffer.
*/
@@ -370,8 +365,6 @@ struct nandsim {
void *file_buf;
struct page *held_pages[NS_MAX_HELD_PAGES];
int held_cnt;
-
- struct nandsim_debug_info dbg;
};
/*
@@ -524,39 +517,18 @@ static const struct file_operations dfs_fops = {
*/
static int nandsim_debugfs_create(struct nandsim *dev)
{
- struct nandsim_debug_info *dbg = &dev->dbg;
+ struct dentry *root = nsmtd->dbg.dfs_dir;
struct dentry *dent;
- if (!IS_ENABLED(CONFIG_DEBUG_FS))
+ if (IS_ERR_OR_NULL(root))
return 0;
- dent = debugfs_create_dir("nandsim", NULL);
- if (!dent) {
- NS_ERR("cannot create \"nandsim\" debugfs directory\n");
- return -ENODEV;
- }
- dbg->dfs_root = dent;
-
dent = debugfs_create_file("wear_report", S_IRUSR,
- dbg->dfs_root, dev, &dfs_fops);
- if (!dent)
- goto out_remove;
- dbg->dfs_wear_report = dent;
+ root, dev, &dfs_fops);
+ if (IS_ERR_OR_NULL(dent))
+ NS_ERR("cannot create \"wear_report\" debugfs entry\n");
return 0;
-
-out_remove:
- debugfs_remove_recursive(dbg->dfs_root);
- return -ENODEV;
-}
-
-/**
- * nandsim_debugfs_remove - destroy all debugfs files
- */
-static void nandsim_debugfs_remove(struct nandsim *ns)
-{
- if (IS_ENABLED(CONFIG_DEBUG_FS))
- debugfs_remove_recursive(ns->dbg.dfs_root);
}
/*
@@ -2395,7 +2367,6 @@ static void __exit ns_cleanup_module(void)
struct nandsim *ns = nand_get_controller_data(chip);
int i;
- nandsim_debugfs_remove(ns);
free_nandsim(ns); /* Free nandsim private resources */
nand_release(nsmtd); /* Unregister driver */
for (i = 0;i < ARRAY_SIZE(ns->partitions); ++i)
diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h
index f8a2ef239c60..6cd0f6b7658b 100644
--- a/include/linux/mtd/mtd.h
+++ b/include/linux/mtd/mtd.h
@@ -206,6 +206,15 @@ struct mtd_pairing_scheme {
struct module; /* only needed for owner field in mtd_info */
+/**
+ * struct mtd_debug_info - debugging information for an MTD device.
+ *
+ * @dfs_dir: direntry object of the MTD device debugfs directory
+ */
+struct mtd_debug_info {
+ struct dentry *dfs_dir;
+};
+
struct mtd_info {
u_char type;
uint32_t flags;
@@ -346,6 +355,7 @@ struct mtd_info {
struct module *owner;
struct device dev;
int usecount;
+ struct mtd_debug_info dbg;
};
int mtd_ooblayout_ecc(struct mtd_info *mtd, int section,
--
2.13.0
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