[PATCH -mm] sysfs_remove_bin_file: no return value, dump_stack on error

Randy.Dunlap
2006-07-11T06:02:42Z

From: Randy Dunlap <rdunlap@xenotime.net>

> So I think a better policy would be to emit a warning from within
> sysfs_remove_bin_file(), then return void. The warning should include the
> stack trace and the filename (if possible).

Make sysfs_remove_bin_file() void. If it detects an error,
printk the file name and call dump_stack().

sysfs_hash_and_remove() now returns an error code indicating
its success or failure so that sysfs_remove_bin_file() can
know success/failure.

Convert the only driver that checked the return value of
sysfs_remove_bin_file().

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
---
drivers/pci/hotplug/acpiphp_ibm.c | 4 +---
fs/sysfs/bin.c | 13 ++++++++-----
fs/sysfs/inode.c | 11 ++++++++---
fs/sysfs/sysfs.h | 2 +-
include/linux/sysfs.h | 2 +-
5 files changed, 19 insertions(+), 13 deletions(-)

--- linux-2618-rc1mm1.orig/fs/sysfs/bin.c
+++ linux-2618-rc1mm1/fs/sysfs/bin.c
@@ -10,6 +10,7 @@

#include <linux/errno.h>
#include <linux/fs.h>
+#include <linux/kernel.h>
#include <linux/kobject.h>
#include <linux/module.h>
#include <linux/slab.h>
@@ -176,7 +177,6 @@ const struct file_operations bin_fops =
* sysfs_create_bin_file - create binary file for object.
* @kobj: object.
* @attr: attribute descriptor.
- *
*/

int sysfs_create_bin_file(struct kobject * kobj, struct bin_attribute * attr)
@@ -191,13 +191,16 @@ int sysfs_create_bin_file(struct kobject
* sysfs_remove_bin_file - remove binary file for object.
* @kobj: object.
* @attr: attribute descriptor.
- *
*/

-int sysfs_remove_bin_file(struct kobject * kobj, struct bin_attribute * attr)
+void sysfs_remove_bin_file(struct kobject * kobj, struct bin_attribute * attr)
{
- sysfs_hash_and_remove(kobj->dentry,attr->attr.name);
- return 0;
+ if (sysfs_hash_and_remove(kobj->dentry, attr->attr.name) < 0) {
+ printk(KERN_ERR "%s: "
+ "bad dentry or inode or no such file: \"%s\"\n",
+ __FUNCTION__, attr->attr.name);
+ dump_stack();
+ }
}

EXPORT_SYMBOL_GPL(sysfs_create_bin_file);
--- linux-2618-rc1mm1.orig/fs/sysfs/inode.c
+++ linux-2618-rc1mm1/fs/sysfs/inode.c
@@ -12,6 +12,7 @@
#include <linux/namei.h>
#include <linux/backing-dev.h>
#include <linux/capability.h>
+#include <linux/errno.h>
#include "sysfs.h"

extern struct super_block * sysfs_sb;
@@ -221,17 +222,18 @@ void sysfs_drop_dentry(struct sysfs_dire
}
}

-void sysfs_hash_and_remove(struct dentry * dir, const char * name)
+int sysfs_hash_and_remove(struct dentry * dir, const char * name)
{
struct sysfs_dirent * sd;
struct sysfs_dirent * parent_sd;
+ int found = 0;

if (!dir)
- return;
+ return -ENOENT;

if (dir->d_inode == NULL)
/* no inode means this hasn't been made visible yet */
- return;
+ return -ENOENT;

parent_sd = dir->d_fsdata;
mutex_lock(&dir->d_inode->i_mutex);
@@ -242,8 +244,11 @@ void sysfs_hash_and_remove(struct dentry
list_del_init(&sd->s_sibling);
sysfs_drop_dentry(sd, dir);
sysfs_put(sd);
+ found = 1;
break;
}
}
mutex_unlock(&dir->d_inode->i_mutex);
+
+ return found ? 0 : -ENOENT;
}
--- linux-2618-rc1mm1.orig/fs/sysfs/sysfs.h
+++ linux-2618-rc1mm1/fs/sysfs/sysfs.h
@@ -10,7 +10,7 @@ extern int sysfs_make_dirent(struct sysf
umode_t, int);

extern int sysfs_add_file(struct dentry *, const struct attribute *, int);
-extern void sysfs_hash_and_remove(struct dentry * dir, const char * name);
+extern int sysfs_hash_and_remove(struct dentry * dir, const char * name);
extern struct sysfs_dirent *sysfs_find(struct sysfs_dirent *dir, const char * name);

extern int sysfs_create_subdir(struct kobject *, const char *, struct dentry **);
--- linux-2618-rc1mm1.orig/include/linux/sysfs.h
+++ linux-2618-rc1mm1/include/linux/sysfs.h
@@ -116,7 +116,7 @@ sysfs_remove_link(struct kobject *, cons

int __must_check sysfs_create_bin_file(struct kobject * kobj,
struct bin_attribute * attr);
-int __must_check sysfs_remove_bin_file(struct kobject * kobj,
+void sysfs_remove_bin_file(struct kobject * kobj,
struct bin_attribute * attr);

int __must_check sysfs_create_group(struct kobject *,
--- linux-2618-rc1mm1.orig/drivers/pci/hotplug/acpiphp_ibm.c
+++ linux-2618-rc1mm1/drivers/pci/hotplug/acpiphp_ibm.c
@@ -487,9 +487,7 @@ static void __exit ibm_acpiphp_exit(void
if (ACPI_FAILURE(status))
err("%s: Notification handler removal failed\n", __FUNCTION__);
/* remove the /sys entries */
- if (sysfs_remove_bin_file(sysdir, &ibm_apci_table_attr))
- err("%s: removal of sysfs file apci_table failed\n",
- __FUNCTION__);
+ sysfs_remove_bin_file(sysdir, &ibm_apci_table_attr);
}

module_init(ibm_acpiphp_init);