1/* SPDX-License-Identifier: BSD-3-Clause */
  2
  3#ifndef _VMBUS_BUF_H_
  4#define _VMBUS_BUF_H_
  5
  6#include <stdbool.h>
  7#include <stdint.h>
  8
  9#define __packed   __attribute__((__packed__))
 10#define unlikely(x)	__builtin_expect(!!(x), 0)
 11
 12#define ICMSGHDRFLAG_TRANSACTION	1
 13#define ICMSGHDRFLAG_REQUEST		2
 14#define ICMSGHDRFLAG_RESPONSE		4
 15
 16#define IC_VERSION_NEGOTIATION_MAX_VER_COUNT 100
 17#define ICMSG_HDR (sizeof(struct vmbuspipe_hdr) + sizeof(struct icmsg_hdr))
 18#define ICMSG_NEGOTIATE_PKT_SIZE(icframe_vercnt, icmsg_vercnt) \
 19	(ICMSG_HDR + sizeof(struct icmsg_negotiate) + \
 20	 (((icframe_vercnt) + (icmsg_vercnt)) * sizeof(struct ic_version)))
 21
 22/*
 23 * Channel packets
 24 */
 25
 26/* Channel packet flags */
 27#define VMBUS_CHANPKT_TYPE_INBAND	0x0006
 28#define VMBUS_CHANPKT_TYPE_RXBUF	0x0007
 29#define VMBUS_CHANPKT_TYPE_GPA		0x0009
 30#define VMBUS_CHANPKT_TYPE_COMP		0x000b
 31
 32#define VMBUS_CHANPKT_FLAG_NONE		0
 33#define VMBUS_CHANPKT_FLAG_RC		0x0001  /* report completion */
 34
 35#define VMBUS_CHANPKT_SIZE_SHIFT	3
 36#define VMBUS_CHANPKT_SIZE_ALIGN	BIT(VMBUS_CHANPKT_SIZE_SHIFT)
 37#define VMBUS_CHANPKT_HLEN_MIN		\
 38	(sizeof(struct vmbus_chanpkt_hdr) >> VMBUS_CHANPKT_SIZE_SHIFT)
 39
 40/*
 41 * Buffer ring
 42 */
 43struct vmbus_bufring {
 44	volatile uint32_t windex;
 45	volatile uint32_t rindex;
 46
 47	/*
 48	 * Interrupt mask {0,1}
 49	 *
 50	 * For TX bufring, host set this to 1, when it is processing
 51	 * the TX bufring, so that we can safely skip the TX event
 52	 * notification to host.
 53	 *
 54	 * For RX bufring, once this is set to 1 by us, host will not
 55	 * further dispatch interrupts to us, even if there are data
 56	 * pending on the RX bufring.  This effectively disables the
 57	 * interrupt of the channel to which this RX bufring is attached.
 58	 */
 59	volatile uint32_t imask;
 60
 61	/*
 62	 * Win8 uses some of the reserved bits to implement
 63	 * interrupt driven flow management. On the send side
 64	 * we can request that the receiver interrupt the sender
 65	 * when the ring transitions from being full to being able
 66	 * to handle a message of size "pending_send_sz".
 67	 *
 68	 * Add necessary state for this enhancement.
 69	 */
 70	volatile uint32_t pending_send;
 71	uint32_t reserved1[12];
 72
 73	union {
 74		struct {
 75			uint32_t feat_pending_send_sz:1;
 76		};
 77		uint32_t value;
 78	} feature_bits;
 79
 80	/* Pad it to rte_mem_page_size() so that data starts on page boundary */
 81	uint8_t	reserved2[4028];
 82
 83	/*
 84	 * Ring data starts here + RingDataStartOffset
 85	 * !!! DO NOT place any fields below this !!!
 86	 */
 87	uint8_t data[];
 88} __packed;
 89
 90struct vmbus_br {
 91	struct vmbus_bufring *vbr;
 92	uint32_t	dsize;
 93	uint32_t	windex; /* next available location */
 94};
 95
 96struct vmbus_chanpkt_hdr {
 97	uint16_t	type;	/* VMBUS_CHANPKT_TYPE_ */
 98	uint16_t	hlen;	/* header len, in 8 bytes */
 99	uint16_t	tlen;	/* total len, in 8 bytes */
100	uint16_t	flags;	/* VMBUS_CHANPKT_FLAG_ */
101	uint64_t	xactid;
102} __packed;
103
104struct vmbus_chanpkt {
105	struct vmbus_chanpkt_hdr hdr;
106} __packed;
107
108struct vmbuspipe_hdr {
109	unsigned int flags;
110	unsigned int msgsize;
111} __packed;
112
113struct ic_version {
114	unsigned short major;
115	unsigned short minor;
116} __packed;
117
118struct icmsg_negotiate {
119	unsigned short icframe_vercnt;
120	unsigned short icmsg_vercnt;
121	unsigned int reserved;
122	struct ic_version icversion_data[]; /* any size array */
123} __packed;
124
125struct icmsg_hdr {
126	struct ic_version icverframe;
127	unsigned short icmsgtype;
128	struct ic_version icvermsg;
129	unsigned short icmsgsize;
130	unsigned int status;
131	unsigned char ictransaction_id;
132	unsigned char icflags;
133	unsigned char reserved[2];
134} __packed;
135
136int rte_vmbus_chan_recv_raw(struct vmbus_br *rxbr, void *data, uint32_t *len);
137int rte_vmbus_chan_send(struct vmbus_br *txbr, uint16_t type, void *data,
138			uint32_t dlen, uint32_t flags);
139void vmbus_br_setup(struct vmbus_br *br, void *buf, unsigned int blen);
140void *vmbus_uio_map(int *fd, int size);
141
142/* Amount of space available for write */
143static inline uint32_t vmbus_br_availwrite(const struct vmbus_br *br, uint32_t windex)
144{
145	uint32_t rindex = br->vbr->rindex;
146
147	if (windex >= rindex)
148		return br->dsize - (windex - rindex);
149	else
150		return rindex - windex;
151}
152
153static inline uint32_t vmbus_br_availread(const struct vmbus_br *br)
154{
155	return br->dsize - vmbus_br_availwrite(br, br->vbr->windex);
156}
157
158#endif	/* !_VMBUS_BUF_H_ */