firewire: Change struct fw_cdev_iso_packet to not use bitfields.

The struct is part of the userspace interface and can not use
bitfields.  This patch replaces the bitfields with a __u32 'control'
word and provides access macros to set the bits.

Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

2 files changed, 24 insertions, 7 deletions

diff --git a/drivers/firewire/fw-cdev.c b/drivers/firewire/fw-cdev.c
index 3ab3585d3601..5d402d63799f 100644
--- a/drivers/firewire/fw-cdev.c
+++ b/drivers/firewire/fw-cdev.c
@@ -677,12 +677,21 @@ static int ioctl_create_iso_context(struct client *client, void *buffer)
         return 0;
 }
 
+/* Macros for decoding the iso packet control header. */
+#define GET_PAYLOAD_LENGTH(v)   ((v) & 0xffff)
+#define GET_INTERRUPT(v)        (((v) >> 16) & 0x01)
+#define GET_SKIP(v)             (((v) >> 17) & 0x01)
+#define GET_TAG(v)              (((v) >> 18) & 0x02)
+#define GET_SY(v)               (((v) >> 20) & 0x04)
+#define GET_HEADER_LENGTH(v)    (((v) >> 24) & 0xff)
+
 static int ioctl_queue_iso(struct client *client, void *buffer)
 {
         struct fw_cdev_queue_iso *request = buffer;
         struct fw_cdev_iso_packet __user *p, *end, *next;
         struct fw_iso_context *ctx = client->iso_context;
         unsigned long payload, buffer_end, header_length;
+        u32 control;
         int count;
         struct {
                 struct fw_iso_packet packet;
@@ -717,8 +726,14 @@ static int ioctl_queue_iso(struct client *client, void *buffer)
         end = (void __user *)p + request->size;
         count = 0;
         while (p < end) {
-                if (__copy_from_user(&u.packet, p, sizeof(*p)))
+                if (get_user(control, &p->control))
                         return -EFAULT;
+                u.packet.payload_length = GET_PAYLOAD_LENGTH(control);
+                u.packet.interrupt = GET_INTERRUPT(control);
+                u.packet.skip = GET_SKIP(control);
+                u.packet.tag = GET_TAG(control);
+                u.packet.sy = GET_SY(control);
+                u.packet.header_length = GET_HEADER_LENGTH(control);
 
                 if (ctx->type == FW_ISO_CONTEXT_TRANSMIT) {
                         header_length = u.packet.header_length;
diff --git a/include/linux/firewire-cdev.h b/include/linux/firewire-cdev.h
index d4455eb2ae35..efbe1fda1a22 100644
--- a/include/linux/firewire-cdev.h
+++ b/include/linux/firewire-cdev.h
@@ -198,13 +198,15 @@ struct fw_cdev_create_iso_context {
         __u32 handle;
 };
 
+#define FW_CDEV_ISO_PAYLOAD_LENGTH(v)   (v)
+#define FW_CDEV_ISO_INTERRUPT           (1 << 16)
+#define FW_CDEV_ISO_SKIP                (1 << 17)
+#define FW_CDEV_ISO_TAG(v)              ((v) << 18)
+#define FW_CDEV_ISO_SY(v)               ((v) << 20)
+#define FW_CDEV_ISO_HEADER_LENGTH(v)    ((v) << 24)
+
 struct fw_cdev_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 control;
         __u32 header[0];
 };