xref: /csrg-svn/sys/vax/if/if_uba.h (revision 5084)
1 /*	if_uba.h	4.2	81/11/26	*/
2 
3 /*
4  * Structure and routine definitions
5  * for UNIBUS network interfaces.
6  */
7 
8 #define	IF_NUBAMR	6
9 /*
10  * Each interface has one of these structures giving information
11  * about UNIBUS resources held by the interface.
12  *
13  * We hold IF_NUBAMR map registers for datagram data, starting
14  * at ifr_mr.  Map register ifr_mr[-1] maps the local network header
15  * ending on the page boundary.  Bdp's are reserved for read and for
16  * write, given by ifr_bdp.  The prototype of the map register for
17  * read and for write is saved in ifr_proto.
18  *
19  * When write transfers are not full pages on page boundaries we just
20  * copy the data into the pages mapped on the UNIBUS and start the
21  * transfer.  If a write transfer is of a (1024 byte) page on a page
22  * boundary, we swap in UNIBUS pte's to reference the pages, and then
23  * remap the initial pages (from ifu_wmap) when the transfer completes.
24  *
25  * When read transfers give whole pages of data to be input, we
26  * allocate page frames from a network page list and trade them
27  * with the pages already containing the data, mapping the allocated
28  * pages to replace the input pages for the next UNIBUS data input.
29  */
30 struct	ifuba {
31 	short	ifu_uban;			/* uba number */
32 	struct	uba_regs *ifu_uba;		/* uba regs, in vm */
33 	struct ifrw {
34 		int	ifrw_info;		/* value from ubaalloc */
35 		short	ifrw_bdp;		/* unibus bdp */
36 		struct	pte *ifrw_mr;		/* base of map registers */
37 		int	ifrw_proto;		/* map register prototype */
38 		caddr_t	ifrw_addr;		/* virt addr of header */
39 	} ifu_r, ifu_w;
40 	struct	pte ifu_wmap[IF_NUBAMR];	/* base pages for output */
41 	short	ifu_hlen;
42 /* ifu_xswapd is set when we have swapped write pte's to do direct output */
43 /* bit i of ifu_xswapd */
44 	short	ifu_xswapd;			/* bit map of pages swapped */
45 	int	ifu_ierrors;
46 	int	ifu_oerrors;
47 	int	ifu_collisions;
48 };
49 
50 #ifdef 	KERNEL
51 struct	mbuf *if_rubaget();
52 #endif
53