/* $NetBSD: xenring.h,v 1.8 2024/07/16 22:44:38 riastradh Exp $ */
/*
* Glue goop for xbd ring request/response protocol structures.
*
* These are used only from __XEN_INTERFACE_VERSION__ >= 0x00030201
* prior to which they were part of the public XEN api.
*/
#ifndef _XEN_RING_H
#define _XEN_RING_H
#if (__XEN_INTERFACE_VERSION__ >= 0x00030201) && \
(__XEN_INTERFACE_VERSION < 0x00030208)
#include <xen/include/public/io/ring.h>
/*
* Undo namespace damage from xen/include/public/io/ring.h
* The proper fix is to get upstream to stop assuming that all OSs use
* mb(), rmb(), wmb().
*/
#undef xen_mb
#undef xen_rmb
#undef xen_wmb
void xen_mb(void);
#define xen_rmb() membar_acquire()
#define xen_wmb() membar_release()
/*
* Define ring types. These were previously part of the public API.
* Not anymore.
*/
/* i386 requests/responses */
struct blkif_x86_32_request {
uint8_t operation; /* BLKIF_OP_??? */
uint8_t nr_segments; /* number of segments */
blkif_vdev_t handle; /* only for read/write requests */
uint64_t id; /* private guest value, echoed in resp */
blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */
struct blkif_request_segment seg[BLKIF_MAX_SEGMENTS_PER_REQUEST];
} __packed;
typedef struct blkif_x86_32_request blkif_x86_32_request_t;
struct blkif_x86_32_response {
uint64_t id; /* copied from request */
uint8_t operation; /* copied from request */
uint8_t _pad;
int16_t status; /* BLKIF_RSP_??? */
} __packed;
typedef struct blkif_x86_32_response blkif_x86_32_response_t;
struct blkif_x86_32_request_indirect {
uint8_t operation; /* BLKIF_OP_INDIRECT */
uint8_t indirect_op; /* BLKIF_OP_{READ/WRITE} */
uint16_t nr_segments; /* number of segments */
uint64_t id; /* private guest value, echoed in resp */
blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */
blkif_vdev_t handle; /* only for read/write requests */
uint16_t _pad2;
grant_ref_t indirect_grefs[BLKIF_MAX_INDIRECT_PAGES_PER_REQUEST];
uint64_t _pad3; /* make it 64 byte aligned */
} __packed;
typedef struct blkif_x86_32_request_indirect blkif_x86_32_request_indirect_t;
/* amd64-type requests/responses (always used in frontends ) */
struct blkif_x86_64_request {
uint8_t operation; /* BLKIF_OP_??? */
uint8_t nr_segments; /* number of segments */
blkif_vdev_t handle; /* only for read/write requests */
uint64_t __attribute__((__aligned__(8))) id;/* private guest value, echoed in resp */
blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */
struct blkif_request_segment seg[BLKIF_MAX_SEGMENTS_PER_REQUEST];
};
typedef struct blkif_x86_64_request blkif_x86_64_request_t;
struct blkif_x86_64_response {
uint64_t __attribute__((__aligned__(8))) id; /* copied from request */
uint8_t operation; /* copied from request */
int16_t status; /* BLKIF_RSP_??? */
};
typedef struct blkif_x86_64_response blkif_x86_64_response_t;
struct blkif_x86_64_request_indirect {
uint8_t operation; /* BLKIF_OP_INDIRECT */
uint8_t indirect_op; /* BLKIF_OP_{READ/WRITE} */
uint16_t nr_segments; /* number of segments */
uint32_t _pad1;
uint64_t id; /* private guest value, echoed in resp */
blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */
blkif_vdev_t handle; /* only for read/write requests */
uint16_t _pad2;
grant_ref_t indirect_grefs[BLKIF_MAX_INDIRECT_PAGES_PER_REQUEST];
uint32_t _pad3; /* make it 64 byte aligned */
} __packed;
typedef struct blkif_x86_64_request_indirect blkif_x86_64_request_indirect_t;
CTASSERT(sizeof(struct blkif_x86_32_request_indirect)
== sizeof(struct blkif_x86_64_request_indirect));
CTASSERT(sizeof(struct blkif_request_indirect)
== sizeof(struct blkif_x86_64_request_indirect));
DEFINE_RING_TYPES(blkif_x86_32, struct blkif_x86_32_request, struct blkif_x86_32_response);
DEFINE_RING_TYPES(blkif_x86_64, struct blkif_x86_64_request, struct blkif_x86_64_response);
union blkif_back_ring_proto {
blkif_back_ring_t ring_n; /* native/common members */
blkif_x86_32_back_ring_t ring_32;
blkif_x86_64_back_ring_t ring_64;
};
typedef union blkif_back_ring_proto blkif_back_ring_proto_t;
#endif /* __XEN_INTERFACE_VERSION__ */
#endif /* _XEN_RING_H_ */