[XFRM]: Optimize MTU calculation
Replace the probing based MTU estimation, which usually takes 2-3 iterations
to find a fitting value and may underestimate the MTU, by an exact calculation.
Also fix underestimation of the XFRM trailer_len, which causes unnecessary
reallocations.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index 5a00aa8..e144a25 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -279,7 +279,7 @@
xfrm_address_t *(*local_addr)(struct xfrm_state *, xfrm_address_t *);
xfrm_address_t *(*remote_addr)(struct xfrm_state *, xfrm_address_t *);
/* Estimate maximal size of result of transformation of a dgram */
- u32 (*get_max_size)(struct xfrm_state *, int size);
+ u32 (*get_mtu)(struct xfrm_state *, int size);
};
extern int xfrm_register_type(struct xfrm_type *type, unsigned short family);