Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c
new file mode 100644
index 0000000..dfdf701
--- /dev/null
+++ b/fs/sysfs/symlink.c
@@ -0,0 +1,180 @@
+/*
+ * symlink.c - operations for sysfs symlinks.
+ */
+
+#include <linux/fs.h>
+#include <linux/module.h>
+#include <linux/kobject.h>
+#include <linux/namei.h>
+
+#include "sysfs.h"
+
+static int object_depth(struct kobject * kobj)
+{
+ struct kobject * p = kobj;
+ int depth = 0;
+ do { depth++; } while ((p = p->parent));
+ return depth;
+}
+
+static int object_path_length(struct kobject * kobj)
+{
+ struct kobject * p = kobj;
+ int length = 1;
+ do {
+ length += strlen(kobject_name(p)) + 1;
+ p = p->parent;
+ } while (p);
+ return length;
+}
+
+static void fill_object_path(struct kobject * kobj, char * buffer, int length)
+{
+ struct kobject * p;
+
+ --length;
+ for (p = kobj; p; p = p->parent) {
+ int cur = strlen(kobject_name(p));
+
+ /* back up enough to print this bus id with '/' */
+ length -= cur;
+ strncpy(buffer + length,kobject_name(p),cur);
+ *(buffer + --length) = '/';
+ }
+}
+
+static int sysfs_add_link(struct dentry * parent, char * name, struct kobject * target)
+{
+ struct sysfs_dirent * parent_sd = parent->d_fsdata;
+ struct sysfs_symlink * sl;
+ int error = 0;
+
+ error = -ENOMEM;
+ sl = kmalloc(sizeof(*sl), GFP_KERNEL);
+ if (!sl)
+ goto exit1;
+
+ sl->link_name = kmalloc(strlen(name) + 1, GFP_KERNEL);
+ if (!sl->link_name)
+ goto exit2;
+
+ strcpy(sl->link_name, name);
+ sl->target_kobj = kobject_get(target);
+
+ error = sysfs_make_dirent(parent_sd, NULL, sl, S_IFLNK|S_IRWXUGO,
+ SYSFS_KOBJ_LINK);
+ if (!error)
+ return 0;
+
+ kfree(sl->link_name);
+exit2:
+ kfree(sl);
+exit1:
+ return error;
+}
+
+/**
+ * sysfs_create_link - create symlink between two objects.
+ * @kobj: object whose directory we're creating the link in.
+ * @target: object we're pointing to.
+ * @name: name of the symlink.
+ */
+int sysfs_create_link(struct kobject * kobj, struct kobject * target, char * name)
+{
+ struct dentry * dentry = kobj->dentry;
+ int error = 0;
+
+ BUG_ON(!kobj || !kobj->dentry || !name);
+
+ down(&dentry->d_inode->i_sem);
+ error = sysfs_add_link(dentry, name, target);
+ up(&dentry->d_inode->i_sem);
+ return error;
+}
+
+
+/**
+ * sysfs_remove_link - remove symlink in object's directory.
+ * @kobj: object we're acting for.
+ * @name: name of the symlink to remove.
+ */
+
+void sysfs_remove_link(struct kobject * kobj, char * name)
+{
+ sysfs_hash_and_remove(kobj->dentry,name);
+}
+
+static int sysfs_get_target_path(struct kobject * kobj, struct kobject * target,
+ char *path)
+{
+ char * s;
+ int depth, size;
+
+ depth = object_depth(kobj);
+ size = object_path_length(target) + depth * 3 - 1;
+ if (size > PATH_MAX)
+ return -ENAMETOOLONG;
+
+ pr_debug("%s: depth = %d, size = %d\n", __FUNCTION__, depth, size);
+
+ for (s = path; depth--; s += 3)
+ strcpy(s,"../");
+
+ fill_object_path(target, path, size);
+ pr_debug("%s: path = '%s'\n", __FUNCTION__, path);
+
+ return 0;
+}
+
+static int sysfs_getlink(struct dentry *dentry, char * path)
+{
+ struct kobject *kobj, *target_kobj;
+ int error = 0;
+
+ kobj = sysfs_get_kobject(dentry->d_parent);
+ if (!kobj)
+ return -EINVAL;
+
+ target_kobj = sysfs_get_kobject(dentry);
+ if (!target_kobj) {
+ kobject_put(kobj);
+ return -EINVAL;
+ }
+
+ down_read(&sysfs_rename_sem);
+ error = sysfs_get_target_path(kobj, target_kobj, path);
+ up_read(&sysfs_rename_sem);
+
+ kobject_put(kobj);
+ kobject_put(target_kobj);
+ return error;
+
+}
+
+static int sysfs_follow_link(struct dentry *dentry, struct nameidata *nd)
+{
+ int error = -ENOMEM;
+ unsigned long page = get_zeroed_page(GFP_KERNEL);
+ if (page)
+ error = sysfs_getlink(dentry, (char *) page);
+ nd_set_link(nd, error ? ERR_PTR(error) : (char *)page);
+ return 0;
+}
+
+static void sysfs_put_link(struct dentry *dentry, struct nameidata *nd)
+{
+ char *page = nd_get_link(nd);
+ if (!IS_ERR(page))
+ free_page((unsigned long)page);
+}
+
+struct inode_operations sysfs_symlink_inode_operations = {
+ .readlink = generic_readlink,
+ .follow_link = sysfs_follow_link,
+ .put_link = sysfs_put_link,
+};
+
+
+EXPORT_SYMBOL_GPL(sysfs_create_link);
+EXPORT_SYMBOL_GPL(sysfs_remove_link);
+