1 files changed, 19 insertions, 14 deletions

diff --git a/drivers/firewire/core-transaction.c b/drivers/firewire/core-transaction.c
index 87d6f2d2f02d..28a94c7ec6e5 100644
--- a/drivers/firewire/core-transaction.c
+++ b/drivers/firewire/core-transaction.c
@@ -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);
 }