Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux
[platform/adaptation/renesas_rcar/renesas_kernel.git] / drivers / firewire / core-transaction.c
index 87d6f2d..28a94c7 100644 (file)
@@ -31,6 +31,7 @@
 #include <linux/kernel.h>
 #include <linux/list.h>
 #include <linux/module.h>
+#include <linux/rculist.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <linux/string.h>
@@ -489,7 +490,7 @@ static struct fw_address_handler *lookup_overlapping_address_handler(
 {
        struct fw_address_handler *handler;
 
-       list_for_each_entry(handler, list, link) {
+       list_for_each_entry_rcu(handler, list, link) {
                if (handler->offset < offset + length &&
                    offset < handler->offset + handler->length)
                        return handler;
@@ -510,7 +511,7 @@ static struct fw_address_handler *lookup_enclosing_address_handler(
 {
        struct fw_address_handler *handler;
 
-       list_for_each_entry(handler, list, link) {
+       list_for_each_entry_rcu(handler, list, link) {
                if (is_enclosing_handler(handler, offset, length))
                        return handler;
        }
@@ -518,7 +519,7 @@ static struct fw_address_handler *lookup_enclosing_address_handler(
        return NULL;
 }
 
-static DEFINE_SPINLOCK(address_handler_lock);
+static DEFINE_SPINLOCK(address_handler_list_lock);
 static LIST_HEAD(address_handler_list);
 
 const struct fw_address_region fw_high_memory_region =
@@ -555,6 +556,7 @@ static bool is_in_fcp_region(u64 offset, size_t length)
  * the specified callback is invoked.  The parameters passed to the callback
  * give the details of the particular request.
  *
+ * To be called in process context.
  * Return value:  0 on success, non-zero otherwise.
  *
  * The start offset of the handler's address region is determined by
@@ -575,7 +577,7 @@ int fw_core_add_address_handler(struct fw_address_handler *handler,
            handler->length == 0)
                return -EINVAL;
 
-       spin_lock_bh(&address_handler_lock);
+       spin_lock(&address_handler_list_lock);
 
        handler->offset = region->start;
        while (handler->offset + handler->length <= region->end) {
@@ -588,13 +590,13 @@ int fw_core_add_address_handler(struct fw_address_handler *handler,
                if (other != NULL) {
                        handler->offset += other->length;
                } else {
-                       list_add_tail(&handler->link, &address_handler_list);
+                       list_add_tail_rcu(&handler->link, &address_handler_list);
                        ret = 0;
                        break;
                }
        }
 
-       spin_unlock_bh(&address_handler_lock);
+       spin_unlock(&address_handler_list_lock);
 
        return ret;
 }
@@ -603,14 +605,17 @@ EXPORT_SYMBOL(fw_core_add_address_handler);
 /**
  * fw_core_remove_address_handler() - unregister an address handler
  *
+ * To be called in process context.
+ *
  * When fw_core_remove_address_handler() returns, @handler->callback() is
  * guaranteed to not run on any CPU anymore.
  */
 void fw_core_remove_address_handler(struct fw_address_handler *handler)
 {
-       spin_lock_bh(&address_handler_lock);
-       list_del(&handler->link);
-       spin_unlock_bh(&address_handler_lock);
+       spin_lock(&address_handler_list_lock);
+       list_del_rcu(&handler->link);
+       spin_unlock(&address_handler_list_lock);
+       synchronize_rcu();
 }
 EXPORT_SYMBOL(fw_core_remove_address_handler);
 
@@ -844,7 +849,7 @@ static void handle_exclusive_region_request(struct fw_card *card,
        if (tcode == TCODE_LOCK_REQUEST)
                tcode = 0x10 + HEADER_GET_EXTENDED_TCODE(p->header[3]);
 
-       spin_lock_bh(&address_handler_lock);
+       rcu_read_lock();
        handler = lookup_enclosing_address_handler(&address_handler_list,
                                                   offset, request->length);
        if (handler)
@@ -853,7 +858,7 @@ static void handle_exclusive_region_request(struct fw_card *card,
                                          p->generation, offset,
                                          request->data, request->length,
                                          handler->callback_data);
-       spin_unlock_bh(&address_handler_lock);
+       rcu_read_unlock();
 
        if (!handler)
                fw_send_response(card, request, RCODE_ADDRESS_ERROR);
@@ -886,8 +891,8 @@ static void handle_fcp_region_request(struct fw_card *card,
                return;
        }
 
-       spin_lock_bh(&address_handler_lock);
-       list_for_each_entry(handler, &address_handler_list, link) {
+       rcu_read_lock();
+       list_for_each_entry_rcu(handler, &address_handler_list, link) {
                if (is_enclosing_handler(handler, offset, request->length))
                        handler->address_callback(card, NULL, tcode,
                                                  destination, source,
@@ -896,7 +901,7 @@ static void handle_fcp_region_request(struct fw_card *card,
                                                  request->length,
                                                  handler->callback_data);
        }
-       spin_unlock_bh(&address_handler_lock);
+       rcu_read_unlock();
 
        fw_send_response(card, request, RCODE_COMPLETE);
 }