sysfs: reimplement symlink using sysfs_dirent tree

[linux-2.6-omap-h63xx.git] / fs / sysfs / dir.c

diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index 6e8d6f54f08296146b81e7a0548b7bcccbd0b00a..2a94dc36d166d3b64b049f3e3ba49e7f7571ddf4 100644 (file)
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -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);
@@ -52,11 +53,8 @@ void release_sysfs_dirent(struct sysfs_dirent * sd)
  repeat:
        parent_sd = sd->s_parent;
 
-       if (sd->s_type & SYSFS_KOBJ_LINK) {
-               struct sysfs_symlink * sl = sd->s_element;
-               kobject_put(sl->target_kobj);
-               kfree(sl);
-       }
+       if (sd->s_type & SYSFS_KOBJ_LINK)
+               sysfs_put(sd->s_elem.symlink.target_sd);
        if (sd->s_type & SYSFS_COPY_NAME)
                kfree(sd->s_name);
        kfree(sd->s_iattr);
@@ -95,8 +93,7 @@ static struct dentry_operations sysfs_dentry_ops = {
        .d_iput         = sysfs_d_iput,
 };
 
-struct sysfs_dirent *sysfs_new_dirent(const char *name, void *element,
-                                     umode_t mode, int type)
+struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type)
 {
        char *dup_name = NULL;
        struct sysfs_dirent *sd = NULL;
@@ -120,7 +117,6 @@ struct sysfs_dirent *sysfs_new_dirent(const char *name, void *element,
        INIT_LIST_HEAD(&sd->s_sibling);
 
        sd->s_name = name;
-       sd->s_element = element;
        sd->s_mode = mode;
        sd->s_type = type;
 
@@ -160,7 +156,7 @@ int sysfs_dirent_exist(struct sysfs_dirent *parent_sd,
        struct sysfs_dirent * sd;
 
        list_for_each_entry(sd, &parent_sd->s_children, s_sibling) {
-               if (sd->s_element) {
+               if (sd->s_type) {
                        if (strcmp(sd->s_name, new))
                                continue;
                        else
@@ -215,9 +211,10 @@ static int create_dir(struct kobject *kobj, struct dentry *parent,
                goto out_dput;
 
        error = -ENOMEM;
-       sd = sysfs_new_dirent(name, kobj, mode, SYSFS_DIR);
+       sd = sysfs_new_dirent(name, mode, SYSFS_DIR);
        if (!sd)
                goto out_drop;
+       sd->s_elem.dir.kobj = kobj;
        sysfs_attach_dirent(sd, parent->d_fsdata, dentry);
 
        error = sysfs_create(dentry, mode, init_dir);
@@ -290,10 +287,10 @@ static int sysfs_attach_attr(struct sysfs_dirent * sd, struct dentry * dentry)
        int error = 0;
 
         if (sd->s_type & SYSFS_KOBJ_BIN_ATTR) {
-                bin_attr = sd->s_element;
+                bin_attr = sd->s_elem.bin_attr.bin_attr;
                 attr = &bin_attr->attr;
         } else {
-                attr = sd->s_element;
+                attr = sd->s_elem.attr.attr;
                 init = init_file;
         }
 
@@ -404,7 +401,7 @@ static void __sysfs_remove_dir(struct dentry *dentry)
        mutex_lock(&dentry->d_inode->i_mutex);
        parent_sd = dentry->d_fsdata;
        list_for_each_entry_safe(sd, tmp, &parent_sd->s_children, s_sibling) {
-               if (!sd->s_element || !(sd->s_type & SYSFS_NOT_PINNED))
+               if (!sd->s_type || !(sd->s_type & SYSFS_NOT_PINNED))
                        continue;
                list_del_init(&sd->s_sibling);
                sysfs_drop_dentry(sd, dentry);
@@ -430,8 +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,
@@ -556,7 +558,7 @@ static int sysfs_dir_open(struct inode *inode, struct file *file)
        struct sysfs_dirent * sd;
 
        mutex_lock(&dentry->d_inode->i_mutex);
-       sd = sysfs_new_dirent("_DIR_", NULL, 0, 0);
+       sd = sysfs_new_dirent("_DIR_", 0, 0);
        if (sd)
                sysfs_attach_dirent(sd, parent_sd, NULL);
        mutex_unlock(&dentry->d_inode->i_mutex);
@@ -623,7 +625,7 @@ static int sysfs_readdir(struct file * filp, void * dirent, filldir_t filldir)
 
                                next = list_entry(p, struct sysfs_dirent,
                                                   s_sibling);
-                               if (!next->s_element)
+                               if (!next->s_type)
                                        continue;
 
                                name = next->s_name;
@@ -671,7 +673,7 @@ static loff_t sysfs_dir_lseek(struct file * file, loff_t offset, int origin)
                                struct sysfs_dirent *next;
                                next = list_entry(p, struct sysfs_dirent,
                                                   s_sibling);
-                               if (next->s_element)
+                               if (next->s_type)
                                        n--;
                                p = p->next;
                        }
@@ -738,9 +740,10 @@ struct dentry *sysfs_create_shadow_dir(struct kobject *kobj)
        if (!shadow)
                goto nomem;
 
-       sd = sysfs_new_dirent("_SHADOW_", kobj, inode->i_mode, SYSFS_DIR);
+       sd = sysfs_new_dirent("_SHADOW_", inode->i_mode, SYSFS_DIR);
        if (!sd)
                goto nomem;
+       sd->s_elem.dir.kobj = kobj;
        /* point to parent_sd but don't attach to it */
        sd->s_parent = sysfs_get(parent_sd);
        sysfs_attach_dirent(sd, NULL, shadow);