drm: move drm authentication to new generic hash table.
Fix drm_remove_magic potential memory leak / corruption. Move drm
authentication token hashing to new generic hash table implementation.
Signed-off-by: Dave Airlie <airlied@linux.ie>
diff --git a/drivers/char/drm/drm_auth.c b/drivers/char/drm/drm_auth.c
index 2a37586..40cd262 100644
--- a/drivers/char/drm/drm_auth.c
+++ b/drivers/char/drm/drm_auth.c
@@ -36,20 +36,6 @@
#include "drmP.h"
/**
- * Generate a hash key from a magic.
- *
- * \param magic magic.
- * \return hash key.
- *
- * The key is the modulus of the hash table size, #DRM_HASH_SIZE, which must be
- * a power of 2.
- */
-static int drm_hash_magic(drm_magic_t magic)
-{
- return magic & (DRM_HASH_SIZE - 1);
-}
-
-/**
* Find the file with the given magic number.
*
* \param dev DRM device.
@@ -63,14 +49,12 @@
{
drm_file_t *retval = NULL;
drm_magic_entry_t *pt;
- int hash = drm_hash_magic(magic);
+ drm_hash_item_t *hash;
mutex_lock(&dev->struct_mutex);
- for (pt = dev->magiclist[hash].head; pt; pt = pt->next) {
- if (pt->magic == magic) {
- retval = pt->priv;
- break;
- }
+ if (!drm_ht_find_item(&dev->magiclist, (unsigned long)magic, &hash)) {
+ pt = drm_hash_entry(hash, drm_magic_entry_t, hash_item);
+ retval = pt->priv;
}
mutex_unlock(&dev->struct_mutex);
return retval;
@@ -90,28 +74,20 @@
static int drm_add_magic(drm_device_t * dev, drm_file_t * priv,
drm_magic_t magic)
{
- int hash;
drm_magic_entry_t *entry;
DRM_DEBUG("%d\n", magic);
- hash = drm_hash_magic(magic);
entry = drm_alloc(sizeof(*entry), DRM_MEM_MAGIC);
if (!entry)
return -ENOMEM;
memset(entry, 0, sizeof(*entry));
- entry->magic = magic;
entry->priv = priv;
- entry->next = NULL;
+ entry->hash_item.key = (unsigned long)magic;
mutex_lock(&dev->struct_mutex);
- if (dev->magiclist[hash].tail) {
- dev->magiclist[hash].tail->next = entry;
- dev->magiclist[hash].tail = entry;
- } else {
- dev->magiclist[hash].head = entry;
- dev->magiclist[hash].tail = entry;
- }
+ drm_ht_insert_item(&dev->magiclist, &entry->hash_item);
+ list_add_tail(&entry->head, &dev->magicfree);
mutex_unlock(&dev->struct_mutex);
return 0;
@@ -128,29 +104,19 @@
*/
static int drm_remove_magic(drm_device_t * dev, drm_magic_t magic)
{
- drm_magic_entry_t *prev = NULL;
drm_magic_entry_t *pt;
- int hash;
+ drm_hash_item_t *hash;
DRM_DEBUG("%d\n", magic);
- hash = drm_hash_magic(magic);
mutex_lock(&dev->struct_mutex);
- for (pt = dev->magiclist[hash].head; pt; prev = pt, pt = pt->next) {
- if (pt->magic == magic) {
- if (dev->magiclist[hash].head == pt) {
- dev->magiclist[hash].head = pt->next;
- }
- if (dev->magiclist[hash].tail == pt) {
- dev->magiclist[hash].tail = prev;
- }
- if (prev) {
- prev->next = pt->next;
- }
- mutex_unlock(&dev->struct_mutex);
- return 0;
- }
+ if (drm_ht_find_item(&dev->magiclist, (unsigned long)magic, &hash)) {
+ mutex_unlock(&dev->struct_mutex);
+ return -EINVAL;
}
+ pt = drm_hash_entry(hash, drm_magic_entry_t, hash_item);
+ drm_ht_remove_item(&dev->magiclist, hash);
+ list_del(&pt->head);
mutex_unlock(&dev->struct_mutex);
drm_free(pt, sizeof(*pt), DRM_MEM_MAGIC);