diff options
| -rw-r--r-- | drivers/block/xen-blkfront.c | 2 | ||||
| -rw-r--r-- | drivers/net/xen-netfront.c | 4 | ||||
| -rw-r--r-- | include/xen/interface/io/ring.h | 11 |
3 files changed, 12 insertions, 5 deletions
diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c index 4f9e22f29138..657873e4328d 100644 --- a/drivers/block/xen-blkfront.c +++ b/drivers/block/xen-blkfront.c @@ -72,7 +72,7 @@ struct blk_shadow { static DEFINE_MUTEX(blkfront_mutex); static const struct block_device_operations xlvbd_block_fops; -#define BLK_RING_SIZE __RING_SIZE((struct blkif_sring *)0, PAGE_SIZE) +#define BLK_RING_SIZE __CONST_RING_SIZE(blkif, PAGE_SIZE) /* * We have one of these per vbd, whether ide, scsi or 'other'. They diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c index 458bb57914a3..cdbeec9f83ea 100644 --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -66,8 +66,8 @@ struct netfront_cb { #define GRANT_INVALID_REF 0 -#define NET_TX_RING_SIZE __RING_SIZE((struct xen_netif_tx_sring *)0, PAGE_SIZE) -#define NET_RX_RING_SIZE __RING_SIZE((struct xen_netif_rx_sring *)0, PAGE_SIZE) +#define NET_TX_RING_SIZE __CONST_RING_SIZE(xen_netif_tx, PAGE_SIZE) +#define NET_RX_RING_SIZE __CONST_RING_SIZE(xen_netif_rx, PAGE_SIZE) #define TX_MAX_TARGET min_t(int, NET_RX_RING_SIZE, 256) struct netfront_info { diff --git a/include/xen/interface/io/ring.h b/include/xen/interface/io/ring.h index e8cbf431c8cc..75271b9a8f61 100644 --- a/include/xen/interface/io/ring.h +++ b/include/xen/interface/io/ring.h @@ -24,8 +24,15 @@ typedef unsigned int RING_IDX; * A ring contains as many entries as will fit, rounded down to the nearest * power of two (so we can mask with (size-1) to loop around). */ -#define __RING_SIZE(_s, _sz) \ - (__RD32(((_sz) - (long)&(_s)->ring + (long)(_s)) / sizeof((_s)->ring[0]))) +#define __CONST_RING_SIZE(_s, _sz) \ + (__RD32(((_sz) - offsetof(struct _s##_sring, ring)) / \ + sizeof(((struct _s##_sring *)0)->ring[0]))) + +/* + * The same for passing in an actual pointer instead of a name tag. + */ +#define __RING_SIZE(_s, _sz) \ + (__RD32(((_sz) - (long)&(_s)->ring + (long)(_s)) / sizeof((_s)->ring[0]))) /* * Macros to make the correct C datatypes for a new kind of ring. |