xen: fix style of hw/block/xen_blkif.h
[qemu/ar7.git] / hw / block / xen_blkif.h
blob7ccf92ec2a7a47e4284980bf04dda5f7af79e866
1 #ifndef __XEN_BLKIF_H__
2 #define __XEN_BLKIF_H__
4 #include <xen/io/ring.h>
5 #include <xen/io/blkif.h>
6 #include <xen/io/protocols.h>
8 /*
9 * Not a real protocol. Used to generate ring structs which contain
10 * the elements common to all protocols only. This way we get a
11 * compiler-checkable way to use common struct elements, so we can
12 * avoid using switch(protocol) in a number of places.
14 struct blkif_common_request {
15 char dummy;
17 struct blkif_common_response {
18 char dummy;
21 /* i386 protocol version */
22 #pragma pack(push, 4)
23 struct blkif_x86_32_request {
24 uint8_t operation; /* BLKIF_OP_??? */
25 uint8_t nr_segments; /* number of segments */
26 blkif_vdev_t handle; /* only for read/write requests */
27 uint64_t id; /* private guest value, echoed in resp */
28 blkif_sector_t sector_number; /* start sector idx on disk (r/w only) */
29 struct blkif_request_segment seg[BLKIF_MAX_SEGMENTS_PER_REQUEST];
31 struct blkif_x86_32_response {
32 uint64_t id; /* copied from request */
33 uint8_t operation; /* copied from request */
34 int16_t status; /* BLKIF_RSP_??? */
36 typedef struct blkif_x86_32_request blkif_x86_32_request_t;
37 typedef struct blkif_x86_32_response blkif_x86_32_response_t;
38 #pragma pack(pop)
40 /* x86_64 protocol version */
41 struct blkif_x86_64_request {
42 uint8_t operation; /* BLKIF_OP_??? */
43 uint8_t nr_segments; /* number of segments */
44 blkif_vdev_t handle; /* only for read/write requests */
45 uint64_t __attribute__((__aligned__(8))) id;
46 blkif_sector_t sector_number; /* start sector idx on disk (r/w only) */
47 struct blkif_request_segment seg[BLKIF_MAX_SEGMENTS_PER_REQUEST];
49 struct blkif_x86_64_response {
50 uint64_t __attribute__((__aligned__(8))) id;
51 uint8_t operation; /* copied from request */
52 int16_t status; /* BLKIF_RSP_??? */
54 typedef struct blkif_x86_64_request blkif_x86_64_request_t;
55 typedef struct blkif_x86_64_response blkif_x86_64_response_t;
57 DEFINE_RING_TYPES(blkif_common, struct blkif_common_request,
58 struct blkif_common_response);
59 DEFINE_RING_TYPES(blkif_x86_32, struct blkif_x86_32_request,
60 struct blkif_x86_32_response);
61 DEFINE_RING_TYPES(blkif_x86_64, struct blkif_x86_64_request,
62 struct blkif_x86_64_response);
64 union blkif_back_rings {
65 blkif_back_ring_t native;
66 blkif_common_back_ring_t common;
67 blkif_x86_32_back_ring_t x86_32_part;
68 blkif_x86_64_back_ring_t x86_64_part;
70 typedef union blkif_back_rings blkif_back_rings_t;
72 enum blkif_protocol {
73 BLKIF_PROTOCOL_NATIVE = 1,
74 BLKIF_PROTOCOL_X86_32 = 2,
75 BLKIF_PROTOCOL_X86_64 = 3,
78 static inline void blkif_get_x86_32_req(blkif_request_t *dst,
79 blkif_x86_32_request_t *src)
81 int i, n = BLKIF_MAX_SEGMENTS_PER_REQUEST;
83 dst->operation = src->operation;
84 dst->nr_segments = src->nr_segments;
85 dst->handle = src->handle;
86 dst->id = src->id;
87 dst->sector_number = src->sector_number;
88 /* Prevent the compiler from using src->... instead. */
89 barrier();
90 if (dst->operation == BLKIF_OP_DISCARD) {
91 struct blkif_request_discard *s = (void *)src;
92 struct blkif_request_discard *d = (void *)dst;
93 d->nr_sectors = s->nr_sectors;
94 return;
96 if (n > dst->nr_segments) {
97 n = dst->nr_segments;
99 for (i = 0; i < n; i++) {
100 dst->seg[i] = src->seg[i];
104 static inline void blkif_get_x86_64_req(blkif_request_t *dst,
105 blkif_x86_64_request_t *src)
107 int i, n = BLKIF_MAX_SEGMENTS_PER_REQUEST;
109 dst->operation = src->operation;
110 dst->nr_segments = src->nr_segments;
111 dst->handle = src->handle;
112 dst->id = src->id;
113 dst->sector_number = src->sector_number;
114 /* Prevent the compiler from using src->... instead. */
115 barrier();
116 if (dst->operation == BLKIF_OP_DISCARD) {
117 struct blkif_request_discard *s = (void *)src;
118 struct blkif_request_discard *d = (void *)dst;
119 d->nr_sectors = s->nr_sectors;
120 return;
122 if (n > dst->nr_segments) {
123 n = dst->nr_segments;
125 for (i = 0; i < n; i++) {
126 dst->seg[i] = src->seg[i];
130 #endif /* __XEN_BLKIF_H__ */