firewire: add IPv4 support

Implement IPv4 over IEEE 1394 as per RFC 2734 for the newer firewire
stack.  This feature has only been present in the older ieee1394 stack
via the eth1394 driver.

Still to do:
  - fix ipv4_priv and ipv4_node lifetime logic
  - fix determination of speeds and max payloads
  - fix bus reset handling
  - fix unaligned memory accesses
  - fix coding style
  - further testing/ improvement of fragment reassembly
  - perhaps multicast support

Signed-off-by: Jay Fenlason <fenlason@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (rebased, copyright note, changelog)

1 files changed, 94 insertions, 0 deletions

diff --git a/include/linux/firewire.h b/include/linux/firewire.h
index e584b7215e8b..d44f47d3b2d9 100644
--- a/include/linux/firewire.h
+++ b/include/linux/firewire.h
@@ -3,6 +3,7 @@
 
 #include <linux/completion.h>
 #include <linux/device.h>
+#include <linux/dma-mapping.h>
 #include <linux/kernel.h>
 #include <linux/kref.h>
 #include <linux/list.h>
@@ -130,6 +131,13 @@ struct fw_card {
         bool broadcast_channel_allocated;
         u32 broadcast_channel;
         u32 topology_map[(CSR_TOPOLOGY_MAP_END - CSR_TOPOLOGY_MAP) / 4];
+        /* Only non-NULL if firewire-ipv4 is active on this card. */
+        void *netdev;
+        /*
+         * The nodes get probed before the card, so we need a place to store
+         * them independent of card->netdev
+         */
+        struct list_head ipv4_nodes;
 };
 
 static inline struct fw_card *fw_card_get(struct fw_card *card)
@@ -355,4 +363,90 @@ int fw_run_transaction(struct fw_card *card, int tcode, int destination_id,
                        int generation, int speed, unsigned long long offset,
                        void *payload, size_t length);
 
+static inline int fw_stream_packet_destination_id(int tag, int channel, int sy)
+{
+        return tag << 14 | channel << 8 | sy;
+}
+
+struct fw_descriptor {
+        struct list_head link;
+        size_t length;
+        u32 immediate;
+        u32 key;
+        const u32 *data;
+};
+
+int fw_core_add_descriptor(struct fw_descriptor *desc);
+void fw_core_remove_descriptor(struct fw_descriptor *desc);
+
+/*
+ * The iso packet format allows for an immediate header/payload part
+ * stored in 'header' immediately after the packet info plus an
+ * indirect payload part that is pointer to by the 'payload' field.
+ * Applications can use one or the other or both to implement simple
+ * low-bandwidth streaming (e.g. audio) or more advanced
+ * scatter-gather streaming (e.g. assembling video frame automatically).
+ */
+struct fw_iso_packet {
+        u16 payload_length;     /* Length of indirect payload. */
+        u32 interrupt:1;        /* Generate interrupt on this packet */
+        u32 skip:1;             /* Set to not send packet at all. */
+        u32 tag:2;
+        u32 sy:4;
+        u32 header_length:8;    /* Length of immediate header. */
+        u32 header[0];
+};
+
+#define FW_ISO_CONTEXT_TRANSMIT 0
+#define FW_ISO_CONTEXT_RECEIVE  1
+
+#define FW_ISO_CONTEXT_MATCH_TAG0        1
+#define FW_ISO_CONTEXT_MATCH_TAG1        2
+#define FW_ISO_CONTEXT_MATCH_TAG2        4
+#define FW_ISO_CONTEXT_MATCH_TAG3        8
+#define FW_ISO_CONTEXT_MATCH_ALL_TAGS   15
+
+/*
+ * An iso buffer is just a set of pages mapped for DMA in the
+ * specified direction.  Since the pages are to be used for DMA, they
+ * are not mapped into the kernel virtual address space.  We store the
+ * DMA address in the page private. The helper function
+ * fw_iso_buffer_map() will map the pages into a given vma.
+ */
+struct fw_iso_buffer {
+        enum dma_data_direction direction;
+        struct page **pages;
+        int page_count;
+};
+
+int fw_iso_buffer_init(struct fw_iso_buffer *buffer, struct fw_card *card,
+                       int page_count, enum dma_data_direction direction);
+void fw_iso_buffer_destroy(struct fw_iso_buffer *buffer, struct fw_card *card);
+
+struct fw_iso_context;
+typedef void (*fw_iso_callback_t)(struct fw_iso_context *context,
+                                  u32 cycle, size_t header_length,
+                                  void *header, void *data);
+struct fw_iso_context {
+        struct fw_card *card;
+        int type;
+        int channel;
+        int speed;
+        size_t header_size;
+        fw_iso_callback_t callback;
+        void *callback_data;
+};
+
+struct fw_iso_context *fw_iso_context_create(struct fw_card *card,
+                int type, int channel, int speed, size_t header_size,
+                fw_iso_callback_t callback, void *callback_data);
+int fw_iso_context_queue(struct fw_iso_context *ctx,
+                         struct fw_iso_packet *packet,
+                         struct fw_iso_buffer *buffer,
+                         unsigned long payload);
+int fw_iso_context_start(struct fw_iso_context *ctx,
+                         int cycle, int sync, int tags);
+int fw_iso_context_stop(struct fw_iso_context *ctx);
+void fw_iso_context_destroy(struct fw_iso_context *ctx);
+
 #endif /* _LINUX_FIREWIRE_H */