[PATCH v7] mtd: create per-device and module-scope debugfs entries
Mario J. Rugiero
mrugiero at gmail.com
Mon May 29 03:23:48 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.
The tree is registered in add_mtd_device, and released in
del_mtd_device.
Devices docg3, mtdswap and nandsim were updated to use this subtree
instead of custom ones, and their entries were prefixed with the
drivers' names.
Signed-off-by: Mario J. Rugiero <mrugiero at gmail.com>
---
v7: - as per derRichard and bbrezillon suggestion, dev_names are used
instead of 'pretty' names for the entries, and driver-specific
entries are prefixed with the drivers' names.
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 | 2 --
drivers/mtd/mtdcore.c | 16 +++++++++++++++
drivers/mtd/mtdswap.c | 18 ++++------------
drivers/mtd/nand/nandsim.c | 50 ++++++++++++---------------------------------
include/linux/mtd/mtd.h | 10 +++++++++
6 files changed, 60 insertions(+), 85 deletions(-)
diff --git a/drivers/mtd/devices/docg3.c b/drivers/mtd/devices/docg3.c
index b833e6cc684c..84b16133554b 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("docg3_flashcontrol", S_IRUSR, root, docg3,
+ &flashcontrol_fops);
+ debugfs_create_file("docg3_asic_mode", S_IRUSR, root, docg3,
+ &asic_mode_fops);
+ debugfs_create_file("docg3_device_id", S_IRUSR, root, docg3,
+ &device_id_fops);
+ debugfs_create_file("docg3_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..e99946575398 100644
--- a/drivers/mtd/devices/docg3.h
+++ b/drivers/mtd/devices/docg3.h
@@ -299,7 +299,6 @@ struct docg3_cascade {
* @oob_autoecc: if 1, use only bytes 0-7, 15, and fill the others with HW ECC
* if 0, use all the 16 bytes.
* @oob_write_buf: prepared OOB for next page_write
- * @debugfs_root: debugfs root node
*/
struct docg3 {
struct device *dev;
@@ -312,7 +311,6 @@ 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..fe48cb1b381b 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>
@@ -477,6 +478,8 @@ int mtd_pairing_groups(struct mtd_info *mtd)
}
EXPORT_SYMBOL_GPL(mtd_pairing_groups);
+static struct dentry *dfs_dir_mtd;
+
/**
* add_mtd_device - register an MTD device
* @mtd: pointer to new MTD device info structure
@@ -552,6 +555,14 @@ int add_mtd_device(struct mtd_info *mtd)
if (error)
goto fail_added;
+ if (!IS_ERR_OR_NULL(dfs_dir_mtd)) {
+ mtd->dbg.dfs_dir = debugfs_create_dir(dev_name(&mtd->dev), dfs_dir_mtd);
+ if (IS_ERR_OR_NULL(mtd->dbg.dfs_dir)) {
+ pr_debug("mtd device %s won't show data in debugfs\n",
+ dev_name(&mtd->dev));
+ }
+ }
+
device_create(&mtd_class, mtd->dev.parent, MTD_DEVT(i) + 1, NULL,
"mtd%dro", i);
@@ -594,6 +605,8 @@ int del_mtd_device(struct mtd_info *mtd)
mutex_lock(&mtd_table_mutex);
+ debugfs_remove_recursive(mtd->dbg.dfs_dir);
+
if (idr_find(&mtd_idr, mtd->index) != mtd) {
ret = -ENODEV;
goto out_error;
@@ -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..93e7c076ab08 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,
+ dent = debugfs_create_file("mtdswap_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..01612fc9f1b6 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 +517,23 @@ 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_ENABLED(CONFIG_DEBUGFS))
return 0;
- dent = debugfs_create_dir("nandsim", NULL);
- if (!dent) {
- NS_ERR("cannot create \"nandsim\" debugfs directory\n");
- return -ENODEV;
- }
- dbg->dfs_root = dent;
+ if (IS_ERR_OR_NULL(root))
+ return -1;
- dent = debugfs_create_file("wear_report", S_IRUSR,
- dbg->dfs_root, dev, &dfs_fops);
- if (!dent)
- goto out_remove;
- dbg->dfs_wear_report = dent;
+ dent = debugfs_create_file("nandsim_wear_report", S_IRUSR,
+ root, dev, &dfs_fops);
+ if (IS_ERR_OR_NULL(dent)) {
+ NS_ERR("cannot create \"nandsim_wear_report\" debugfs entry\n");
+ return -1;
+ }
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);
}
/*
@@ -2352,9 +2329,6 @@ static int __init ns_init_module(void)
if ((retval = setup_wear_reporting(nsmtd)) != 0)
goto err_exit;
- if ((retval = nandsim_debugfs_create(nand)) != 0)
- goto err_exit;
-
if ((retval = init_nandsim(nsmtd)) != 0)
goto err_exit;
@@ -2370,6 +2344,9 @@ static int __init ns_init_module(void)
if (retval != 0)
goto err_exit;
+ if ((retval = nandsim_debugfs_create(nand)) != 0)
+ goto err_exit;
+
return 0;
err_exit:
@@ -2395,7 +2372,6 @@ 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
More information about the linux-mtd
mailing list