1 files changed, 0 insertions, 356 deletions
diff --git a/fs/dcookies.c b/fs/dcookies.c
deleted file mode 100644
index 6eeb61100a09..000000000000
--- a/fs/dcookies.c
+++ /dev/null
@@ -1,356 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * dcookies.c
- *
- * Copyright 2002 John Levon <levon@movementarian.org>
- *
- * Persistent cookie-path mappings. These are used by
- * profilers to convert a per-task EIP value into something
- * non-transitory that can be processed at a later date.
- * This is done by locking the dentry/vfsmnt pair in the
- * kernel until released by the tasks needing the persistent
- * objects. The tag is simply an unsigned long that refers
- * to the pair and can be looked up from userspace.
- */
-
-#include <linux/syscalls.h>
-#include <linux/export.h>
-#include <linux/slab.h>
-#include <linux/list.h>
-#include <linux/mount.h>
-#include <linux/capability.h>
-#include <linux/dcache.h>
-#include <linux/mm.h>
-#include <linux/err.h>
-#include <linux/errno.h>
-#include <linux/dcookies.h>
-#include <linux/mutex.h>
-#include <linux/path.h>
-#include <linux/compat.h>
-#include <linux/uaccess.h>
-
-/* The dcookies are allocated from a kmem_cache and
- * hashed onto a small number of lists. None of the
- * code here is particularly performance critical
- */
-struct dcookie_struct {
-	struct path path;
-	struct list_head hash_list;
-};
-
-static LIST_HEAD(dcookie_users);
-static DEFINE_MUTEX(dcookie_mutex);
-static struct kmem_cache *dcookie_cache __read_mostly;
-static struct list_head *dcookie_hashtable __read_mostly;
-static size_t hash_size __read_mostly;
-
-static inline int is_live(void)
-{
-	return !(list_empty(&dcookie_users));
-}
-
-
-/* The dentry is locked, its address will do for the cookie */
-static inline unsigned long dcookie_value(struct dcookie_struct * dcs)
-{
-	return (unsigned long)dcs->path.dentry;
-}
-
-
-static size_t dcookie_hash(unsigned long dcookie)
-{
-	return (dcookie >> L1_CACHE_SHIFT) & (hash_size - 1);
-}
-
-
-static struct dcookie_struct * find_dcookie(unsigned long dcookie)
-{
-	struct dcookie_struct *found = NULL;
-	struct dcookie_struct * dcs;
-	struct list_head * pos;
-	struct list_head * list;
-
-	list = dcookie_hashtable + dcookie_hash(dcookie);
-
-	list_for_each(pos, list) {
-		dcs = list_entry(pos, struct dcookie_struct, hash_list);
-		if (dcookie_value(dcs) == dcookie) {
-			found = dcs;
-			break;
-		}
-	}
-
-	return found;
-}
-
-
-static void hash_dcookie(struct dcookie_struct * dcs)
-{
-	struct list_head * list = dcookie_hashtable + dcookie_hash(dcookie_value(dcs));
-	list_add(&dcs->hash_list, list);
-}
-
-
-static struct dcookie_struct *alloc_dcookie(const struct path *path)
-{
-	struct dcookie_struct *dcs = kmem_cache_alloc(dcookie_cache,
-							GFP_KERNEL);
-	struct dentry *d;
-	if (!dcs)
-		return NULL;
-
-	d = path->dentry;
-	spin_lock(&d->d_lock);
-	d->d_flags |= DCACHE_COOKIE;
-	spin_unlock(&d->d_lock);
-
-	dcs->path = *path;
-	path_get(path);
-	hash_dcookie(dcs);
-	return dcs;
-}
-
-
-/* This is the main kernel-side routine that retrieves the cookie
- * value for a dentry/vfsmnt pair.
- */
-int get_dcookie(const struct path *path, unsigned long *cookie)
-{
-	int err = 0;
-	struct dcookie_struct * dcs;
-
-	mutex_lock(&dcookie_mutex);
-
-	if (!is_live()) {
-		err = -EINVAL;
-		goto out;
-	}
-
-	if (path->dentry->d_flags & DCACHE_COOKIE) {
-		dcs = find_dcookie((unsigned long)path->dentry);
-	} else {
-		dcs = alloc_dcookie(path);
-		if (!dcs) {
-			err = -ENOMEM;
-			goto out;
-		}
-	}
-
-	*cookie = dcookie_value(dcs);
-
-out:
-	mutex_unlock(&dcookie_mutex);
-	return err;
-}
-
-
-/* And here is where the userspace process can look up the cookie value
- * to retrieve the path.
- */
-static int do_lookup_dcookie(u64 cookie64, char __user *buf, size_t len)
-{
-	unsigned long cookie = (unsigned long)cookie64;
-	int err = -EINVAL;
-	char * kbuf;
-	char * path;
-	size_t pathlen;
-	struct dcookie_struct * dcs;
-
-	/* we could leak path information to users
-	 * without dir read permission without this
-	 */
-	if (!capable(CAP_SYS_ADMIN))
-		return -EPERM;
-
-	mutex_lock(&dcookie_mutex);
-
-	if (!is_live()) {
-		err = -EINVAL;
-		goto out;
-	}
-
-	if (!(dcs = find_dcookie(cookie)))
-		goto out;
-
-	err = -ENOMEM;
-	kbuf = kmalloc(PAGE_SIZE, GFP_KERNEL);
-	if (!kbuf)
-		goto out;
-
-	/* FIXME: (deleted) ? */
-	path = d_path(&dcs->path, kbuf, PAGE_SIZE);
-
-	mutex_unlock(&dcookie_mutex);
-
-	if (IS_ERR(path)) {
-		err = PTR_ERR(path);
-		goto out_free;
-	}
-
-	err = -ERANGE;
- 
-	pathlen = kbuf + PAGE_SIZE - path;
-	if (pathlen <= len) {
-		err = pathlen;
-		if (copy_to_user(buf, path, pathlen))
-			err = -EFAULT;
-	}
-
-out_free:
-	kfree(kbuf);
-	return err;
-out:
-	mutex_unlock(&dcookie_mutex);
-	return err;
-}
-
-SYSCALL_DEFINE3(lookup_dcookie, u64, cookie64, char __user *, buf, size_t, len)
-{
-	return do_lookup_dcookie(cookie64, buf, len);
-}
-
-#ifdef CONFIG_COMPAT
-COMPAT_SYSCALL_DEFINE4(lookup_dcookie, u32, w0, u32, w1, char __user *, buf, compat_size_t, len)
-{
-#ifdef __BIG_ENDIAN
-	return do_lookup_dcookie(((u64)w0 << 32) | w1, buf, len);
-#else
-	return do_lookup_dcookie(((u64)w1 << 32) | w0, buf, len);
-#endif
-}
-#endif
-
-static int dcookie_init(void)
-{
-	struct list_head * d;
-	unsigned int i, hash_bits;
-	int err = -ENOMEM;
-
-	dcookie_cache = kmem_cache_create("dcookie_cache",
-		sizeof(struct dcookie_struct),
-		0, 0, NULL);
-
-	if (!dcookie_cache)
-		goto out;
-
-	dcookie_hashtable = kmalloc(PAGE_SIZE, GFP_KERNEL);
-	if (!dcookie_hashtable)
-		goto out_kmem;
-
-	err = 0;
-
-	/*
-	 * Find the power-of-two list-heads that can fit into the allocation..
-	 * We don't guarantee that "sizeof(struct list_head)" is necessarily
-	 * a power-of-two.
-	 */
-	hash_size = PAGE_SIZE / sizeof(struct list_head);
-	hash_bits = 0;
-	do {
-		hash_bits++;
-	} while ((hash_size >> hash_bits) != 0);
-	hash_bits--;
-
-	/*
-	 * Re-calculate the actual number of entries and the mask
-	 * from the number of bits we can fit.
-	 */
-	hash_size = 1UL << hash_bits;
-
-	/* And initialize the newly allocated array */
-	d = dcookie_hashtable;
-	i = hash_size;
-	do {
-		INIT_LIST_HEAD(d);
-		d++;
-		i--;
-	} while (i);
-
-out:
-	return err;
-out_kmem:
-	kmem_cache_destroy(dcookie_cache);
-	goto out;
-}
-
-
-static void free_dcookie(struct dcookie_struct * dcs)
-{
-	struct dentry *d = dcs->path.dentry;
-
-	spin_lock(&d->d_lock);
-	d->d_flags &= ~DCACHE_COOKIE;
-	spin_unlock(&d->d_lock);
-
-	path_put(&dcs->path);
-	kmem_cache_free(dcookie_cache, dcs);
-}
-
-
-static void dcookie_exit(void)
-{
-	struct list_head * list;
-	struct list_head * pos;
-	struct list_head * pos2;
-	struct dcookie_struct * dcs;
-	size_t i;
-
-	for (i = 0; i < hash_size; ++i) {
-		list = dcookie_hashtable + i;
-		list_for_each_safe(pos, pos2, list) {
-			dcs = list_entry(pos, struct dcookie_struct, hash_list);
-			list_del(&dcs->hash_list);
-			free_dcookie(dcs);
-		}
-	}
-
-	kfree(dcookie_hashtable);
-	kmem_cache_destroy(dcookie_cache);
-}
-
-
-struct dcookie_user {
-	struct list_head next;
-};
- 
-struct dcookie_user * dcookie_register(void)
-{
-	struct dcookie_user * user;
-
-	mutex_lock(&dcookie_mutex);
-
-	user = kmalloc(sizeof(struct dcookie_user), GFP_KERNEL);
-	if (!user)
-		goto out;
-
-	if (!is_live() && dcookie_init())
-		goto out_free;
-
-	list_add(&user->next, &dcookie_users);
-
-out:
-	mutex_unlock(&dcookie_mutex);
-	return user;
-out_free:
-	kfree(user);
-	user = NULL;
-	goto out;
-}
-
-
-void dcookie_unregister(struct dcookie_user * user)
-{
-	mutex_lock(&dcookie_mutex);
-
-	list_del(&user->next);
-	kfree(user);
-
-	if (!is_live())
-		dcookie_exit();
-
-	mutex_unlock(&dcookie_mutex);
-}
-
-EXPORT_SYMBOL_GPL(dcookie_register);
-EXPORT_SYMBOL_GPL(dcookie_unregister);
-EXPORT_SYMBOL_GPL(get_dcookie);