4 files changed, 14 insertions, 4 deletions

diff --git a/drivers/firewire/core-cdev.c b/drivers/firewire/core-cdev.c
index 7ef316fdc4d9..ac1b43a04285 100644
--- a/drivers/firewire/core-cdev.c
+++ b/drivers/firewire/core-cdev.c
@@ -54,6 +54,7 @@
 #define FW_CDEV_KERNEL_VERSION                  5
 #define FW_CDEV_VERSION_EVENT_REQUEST2          4
 #define FW_CDEV_VERSION_ALLOCATE_REGION_END     4
+#define FW_CDEV_VERSION_AUTO_FLUSH_ISO_OVERFLOW 5
 
 struct client {
         u32 version;
@@ -1005,6 +1006,8 @@ static int ioctl_create_iso_context(struct client *client, union ioctl_arg *arg)
                         a->channel, a->speed, a->header_size, cb, client);
         if (IS_ERR(context))
                 return PTR_ERR(context);
+        if (client->version < FW_CDEV_VERSION_AUTO_FLUSH_ISO_OVERFLOW)
+                context->drop_overflow_headers = true;
 
         /* We only support one context at this time. */
         spin_lock_irq(&client->lock);
diff --git a/drivers/firewire/ohci.c b/drivers/firewire/ohci.c
index 9e1db6490b9a..afb701ec90ca 100644
--- a/drivers/firewire/ohci.c
+++ b/drivers/firewire/ohci.c
@@ -2749,8 +2749,11 @@ static void copy_iso_headers(struct iso_context *ctx, const u32 *dma_hdr)
 {
         u32 *ctx_hdr;
 
-        if (ctx->header_length + ctx->base.header_size > PAGE_SIZE)
+        if (ctx->header_length + ctx->base.header_size > PAGE_SIZE) {
+                if (ctx->base.drop_overflow_headers)
+                        return;
                 flush_iso_completions(ctx);
+        }
 
         ctx_hdr = ctx->header + ctx->header_length;
         ctx->last_timestamp = (u16)le32_to_cpu((__force __le32)dma_hdr[0]);
@@ -2910,8 +2913,11 @@ static int handle_it_packet(struct context *context,
 
         sync_it_packet_for_cpu(context, d);
 
-        if (ctx->header_length + 4 > PAGE_SIZE)
+        if (ctx->header_length + 4 > PAGE_SIZE) {
+                if (ctx->base.drop_overflow_headers)
+                        return 1;
                 flush_iso_completions(ctx);
+        }
 
         ctx_hdr = ctx->header + ctx->header_length;
         ctx->last_timestamp = le16_to_cpu(last->res_count);
diff --git a/include/linux/firewire.h b/include/linux/firewire.h
index 3b0e820375ab..5d7782e42b8f 100644
--- a/include/linux/firewire.h
+++ b/include/linux/firewire.h
@@ -436,6 +436,7 @@ struct fw_iso_context {
         int type;
         int channel;
         int speed;
+        bool drop_overflow_headers;
         size_t header_size;
         union {
                 fw_iso_callback_t sc;
diff --git a/include/uapi/linux/firewire-cdev.h b/include/uapi/linux/firewire-cdev.h
index d50036953497..1db453e4b550 100644
--- a/include/uapi/linux/firewire-cdev.h
+++ b/include/uapi/linux/firewire-cdev.h
@@ -215,8 +215,8 @@ struct fw_cdev_event_request2 {
  * with the %FW_CDEV_ISO_INTERRUPT bit set, when explicitly requested with
  * %FW_CDEV_IOC_FLUSH_ISO, or when there have been so many completed packets
  * without the interrupt bit set that the kernel's internal buffer for @header
- * is about to overflow.  (In the last case, kernels with ABI version < 5 drop
- * header data up to the next interrupt packet.)
+ * is about to overflow.  (In the last case, ABI versions < 5 drop header data
+ * up to the next interrupt packet.)
  *
  * Isochronous transmit events (context type %FW_CDEV_ISO_CONTEXT_TRANSMIT):
  *