#define fscache_cookie_hash_shift 15
static struct hlist_bl_head fscache_cookie_hash[1 << fscache_cookie_hash_shift];
+static LIST_HEAD(fscache_cookies);
+static DEFINE_RWLOCK(fscache_cookies_lock);
static int fscache_acquire_non_index_cookie(struct fscache_cookie *cookie,
loff_t object_size);
static void fscache_print_cookie(struct fscache_cookie *cookie, char prefix)
{
- struct hlist_node *object;
+ struct fscache_object *object;
+ struct hlist_node *o;
const u8 *k;
unsigned loop;
- pr_err("%c-cookie c=%p [p=%p fl=%lx nc=%u na=%u]\n",
- prefix, cookie, cookie->parent, cookie->flags,
+ pr_err("%c-cookie c=%08x [p=%08x fl=%lx nc=%u na=%u]\n",
+ prefix,
+ cookie->debug_id,
+ cookie->parent ? cookie->parent->debug_id : 0,
+ cookie->flags,
atomic_read(&cookie->n_children),
atomic_read(&cookie->n_active));
- pr_err("%c-cookie d=%p n=%p\n",
- prefix, cookie->def, cookie->netfs_data);
-
- object = READ_ONCE(cookie->backing_objects.first);
- if (object)
- pr_err("%c-cookie o=%p\n",
- prefix, hlist_entry(object, struct fscache_object, cookie_link));
+ pr_err("%c-cookie d=%p{%s} n=%p\n",
+ prefix,
+ cookie->def,
+ cookie->def ? cookie->def->name : "?",
+ cookie->netfs_data);
+
+ o = READ_ONCE(cookie->backing_objects.first);
+ if (o) {
+ object = hlist_entry(o, struct fscache_object, cookie_link);
+ pr_err("%c-cookie o=%u\n", prefix, object->debug_id);
+ }
pr_err("%c-key=[%u] '", prefix, cookie->key_len);
k = (cookie->key_len <= sizeof(cookie->inline_key)) ?
{
if (cookie) {
BUG_ON(!hlist_empty(&cookie->backing_objects));
+ write_lock(&fscache_cookies_lock);
+ list_del(&cookie->proc_link);
+ write_unlock(&fscache_cookies_lock);
if (cookie->aux_len > sizeof(cookie->inline_aux))
kfree(cookie->aux);
if (cookie->key_len > sizeof(cookie->inline_key))
static int fscache_set_key(struct fscache_cookie *cookie,
const void *index_key, size_t index_key_len)
{
- unsigned long long h;
u32 *buf;
int bufs;
- int i;
bufs = DIV_ROUND_UP(index_key_len, sizeof(*buf));
}
memcpy(buf, index_key, index_key_len);
-
- /* Calculate a hash and combine this with the length in the first word
- * or first half word
- */
- h = (unsigned long)cookie->parent;
- h += index_key_len + cookie->type;
-
- for (i = 0; i < bufs; i++)
- h += buf[i];
-
- cookie->key_hash = h ^ (h >> 32);
+ cookie->key_hash = fscache_hash(0, buf, bufs);
return 0;
}
return memcmp(ka, kb, a->key_len);
}
+static atomic_t fscache_cookie_debug_id = ATOMIC_INIT(1);
+
/*
* Allocate a cookie.
*/
goto nomem;
}
- atomic_set(&cookie->usage, 1);
+ refcount_set(&cookie->ref, 1);
atomic_set(&cookie->n_children, 0);
+ cookie->debug_id = atomic_inc_return(&fscache_cookie_debug_id);
/* We keep the active count elevated until relinquishment to prevent an
* attempt to wake up every time the object operations queue quiesces.
/* radix tree insertion won't use the preallocation pool unless it's
* told it may not wait */
INIT_RADIX_TREE(&cookie->stores, GFP_NOFS & ~__GFP_DIRECT_RECLAIM);
+
+ write_lock(&fscache_cookies_lock);
+ list_add_tail(&cookie->proc_link, &fscache_cookies);
+ write_unlock(&fscache_cookies_lock);
return cookie;
nomem:
collision:
if (test_and_set_bit(FSCACHE_COOKIE_ACQUIRED, &cursor->flags)) {
- trace_fscache_cookie(cursor, fscache_cookie_collision,
- atomic_read(&cursor->usage));
+ trace_fscache_cookie(cursor->debug_id, refcount_read(&cursor->ref),
+ fscache_cookie_collision);
pr_err("Duplicate cookie detected\n");
fscache_print_cookie(cursor, 'O');
fscache_print_cookie(candidate, 'N');
cookie = fscache_hash_cookie(candidate);
if (!cookie) {
- trace_fscache_cookie(candidate, fscache_cookie_discard, 1);
+ trace_fscache_cookie(candidate->debug_id, 1,
+ fscache_cookie_discard);
goto out;
}
bool (*can_enable)(void *data),
void *data)
{
- _enter("%p", cookie);
+ _enter("%x", cookie->debug_id);
trace_fscache_enable(cookie);
/* we may be required to wait for lookup to complete at this point */
if (!fscache_defer_lookup) {
- _debug("non-deferred lookup %p", &cookie->flags);
wait_on_bit(&cookie->flags, FSCACHE_COOKIE_LOOKING_UP,
TASK_UNINTERRUPTIBLE);
- _debug("complete");
if (test_bit(FSCACHE_COOKIE_UNAVAILABLE, &cookie->flags))
goto unavailable;
}
struct fscache_object *object;
int ret;
- _enter("%p,%p{%s}", cache, cookie, cookie->def->name);
+ _enter("%s,%x{%s}", cache->tag->name, cookie->debug_id, cookie->def->name);
spin_lock(&cookie->lock);
hlist_for_each_entry(object, &cookie->backing_objects,
/* Attach to the cookie. The object already has a ref on it. */
hlist_add_head(&object->cookie_link, &cookie->backing_objects);
-
- fscache_objlist_add(object);
ret = 0;
cant_attach_object:
*/
void __fscache_wait_on_invalidate(struct fscache_cookie *cookie)
{
- _enter("%p", cookie);
+ _enter("%x", cookie->debug_id);
wait_on_bit(&cookie->flags, FSCACHE_COOKIE_INVALIDATING,
TASK_UNINTERRUPTIBLE);
struct fscache_object *object;
bool awaken = false;
- _enter("%p,%u", cookie, invalidate);
+ _enter("%x,%u", cookie->debug_id, invalidate);
trace_fscache_disable(cookie);
return;
}
- _enter("%p{%s,%p,%d},%d",
- cookie, cookie->def->name, cookie->netfs_data,
+ _enter("%x{%s,%d},%d",
+ cookie->debug_id, cookie->def->name,
atomic_read(&cookie->n_active), retire);
trace_fscache_relinquish(cookie, retire);
BUG_ON(!radix_tree_empty(&cookie->stores));
if (cookie->parent) {
- ASSERTCMP(atomic_read(&cookie->parent->usage), >, 0);
+ ASSERTCMP(refcount_read(&cookie->parent->ref), >, 0);
ASSERTCMP(atomic_read(&cookie->parent->n_children), >, 0);
atomic_dec(&cookie->parent->n_children);
}
/* Dispose of the netfs's link to the cookie */
- ASSERTCMP(atomic_read(&cookie->usage), >, 0);
fscache_cookie_put(cookie, fscache_cookie_put_relinquish);
_leave("");
enum fscache_cookie_trace where)
{
struct fscache_cookie *parent;
- int usage;
+ int ref;
- _enter("%p", cookie);
+ _enter("%x", cookie->debug_id);
do {
- usage = atomic_dec_return(&cookie->usage);
- trace_fscache_cookie(cookie, where, usage);
+ unsigned int cookie_debug_id = cookie->debug_id;
+ bool zero = __refcount_dec_and_test(&cookie->ref, &ref);
- if (usage > 0)
+ trace_fscache_cookie(cookie_debug_id, ref - 1, where);
+ if (!zero)
return;
- BUG_ON(usage < 0);
parent = cookie->parent;
fscache_unhash_cookie(cookie);
_leave("");
}
+/*
+ * Get a reference to a cookie.
+ */
+struct fscache_cookie *fscache_cookie_get(struct fscache_cookie *cookie,
+ enum fscache_cookie_trace where)
+{
+ int ref;
+
+ __refcount_inc(&cookie->ref, &ref);
+ trace_fscache_cookie(cookie->debug_id, ref + 1, where);
+ return cookie;
+}
+
/*
* check the consistency between the netfs inode and the backing cache
*
return -ESTALE;
}
EXPORT_SYMBOL(__fscache_check_consistency);
+
+/*
+ * Generate a list of extant cookies in /proc/fs/fscache/cookies
+ */
+static int fscache_cookies_seq_show(struct seq_file *m, void *v)
+{
+ struct fscache_cookie *cookie;
+ unsigned int keylen = 0, auxlen = 0;
+ char _type[3], *type;
+ u8 *p;
+
+ if (v == &fscache_cookies) {
+ seq_puts(m,
+ "COOKIE PARENT USAGE CHILD ACT TY FL DEF NETFS_DATA\n"
+ "======== ======== ===== ===== === == === ================ ==========\n"
+ );
+ return 0;
+ }
+
+ cookie = list_entry(v, struct fscache_cookie, proc_link);
+
+ switch (cookie->type) {
+ case 0:
+ type = "IX";
+ break;
+ case 1:
+ type = "DT";
+ break;
+ default:
+ snprintf(_type, sizeof(_type), "%02u",
+ cookie->type);
+ type = _type;
+ break;
+ }
+
+ seq_printf(m,
+ "%08x %08x %5u %5u %3u %s %03lx %-16s %px",
+ cookie->debug_id,
+ cookie->parent ? cookie->parent->debug_id : 0,
+ refcount_read(&cookie->ref),
+ atomic_read(&cookie->n_children),
+ atomic_read(&cookie->n_active),
+ type,
+ cookie->flags,
+ cookie->def->name,
+ cookie->netfs_data);
+
+ keylen = cookie->key_len;
+ auxlen = cookie->aux_len;
+
+ if (keylen > 0 || auxlen > 0) {
+ seq_puts(m, " ");
+ p = keylen <= sizeof(cookie->inline_key) ?
+ cookie->inline_key : cookie->key;
+ for (; keylen > 0; keylen--)
+ seq_printf(m, "%02x", *p++);
+ if (auxlen > 0) {
+ seq_puts(m, ", ");
+ p = auxlen <= sizeof(cookie->inline_aux) ?
+ cookie->inline_aux : cookie->aux;
+ for (; auxlen > 0; auxlen--)
+ seq_printf(m, "%02x", *p++);
+ }
+ }
+
+ seq_puts(m, "\n");
+ return 0;
+}
+
+static void *fscache_cookies_seq_start(struct seq_file *m, loff_t *_pos)
+ __acquires(fscache_cookies_lock)
+{
+ read_lock(&fscache_cookies_lock);
+ return seq_list_start_head(&fscache_cookies, *_pos);
+}
+
+static void *fscache_cookies_seq_next(struct seq_file *m, void *v, loff_t *_pos)
+{
+ return seq_list_next(v, &fscache_cookies, _pos);
+}
+
+static void fscache_cookies_seq_stop(struct seq_file *m, void *v)
+ __releases(rcu)
+{
+ read_unlock(&fscache_cookies_lock);
+}
+
+
+const struct seq_operations fscache_cookies_seq_ops = {
+ .start = fscache_cookies_seq_start,
+ .next = fscache_cookies_seq_next,
+ .stop = fscache_cookies_seq_stop,
+ .show = fscache_cookies_seq_show,
+};