Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit aecdceda authored by Tejun Heo's avatar Tejun Heo Committed by Greg Kroah-Hartman
Browse files

sysfs: implement kobj_sysfs_assoc_lock 



kobj->dentry can go away anytime unless the user controls when the
associated sysfs node is deleted.  This patch implements
kobj_sysfs_assoc_lock which protects kobj->dentry.  This will be used
to maintain kobj based API when converting sysfs to use sysfs_dirent
tree instead of dentry/kobject.

Note that this lock belongs to kobject/driver-model not sysfs.  Once
sysfs is converted to not use kobject in its interface, this can be
removed from sysfs.

This is in preparation of object reference simplification.

Signed-off-by: default avatarTejun Heo <htejun@gmail.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 3e519038

fs/sysfs/dir.c

+7 −1
Original line number Diff line number Diff line
@@ -15,6 +15,7 @@ 


DECLARE_RWSEM(sysfs_rename_sem);

spinlock_t sysfs_lock = SPIN_LOCK_UNLOCKED;

spinlock_t kobj_sysfs_assoc_lock = SPIN_LOCK_UNLOCKED;



static spinlock_t sysfs_ino_lock = SPIN_LOCK_UNLOCKED;

static DEFINE_IDA(sysfs_ino_ida);
@@ -426,8 +427,13 @@ static void __sysfs_remove_dir(struct dentry *dentry) 


void sysfs_remove_dir(struct kobject * kobj)

{

	__sysfs_remove_dir(kobj->dentry);

	struct dentry *d = kobj->dentry;



	spin_lock(&kobj_sysfs_assoc_lock);

	kobj->dentry = NULL;

	spin_unlock(&kobj_sysfs_assoc_lock);



	__sysfs_remove_dir(d);

}



int sysfs_rename_dir(struct kobject * kobj, struct dentry *new_parent,

fs/sysfs/sysfs.h

+1 −0
Original line number Diff line number Diff line
@@ -62,6 +62,7 @@ extern void sysfs_drop_dentry(struct sysfs_dirent *sd, struct dentry *parent); 
extern int sysfs_setattr(struct dentry *dentry, struct iattr *iattr);



extern spinlock_t sysfs_lock;

extern spinlock_t kobj_sysfs_assoc_lock;

extern struct rw_semaphore sysfs_rename_sem;

extern struct super_block * sysfs_sb;

extern const struct file_operations sysfs_dir_operations;