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1 | 244ab90e | aliguori | /*
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2 | 244ab90e | aliguori | * DMA helper functions
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3 | 244ab90e | aliguori | *
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4 | 244ab90e | aliguori | * Copyright (c) 2009 Red Hat
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5 | 244ab90e | aliguori | *
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6 | 244ab90e | aliguori | * This work is licensed under the terms of the GNU General Public License
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7 | 244ab90e | aliguori | * (GNU GPL), version 2 or later.
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8 | 244ab90e | aliguori | */
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9 | 244ab90e | aliguori | |
10 | 244ab90e | aliguori | #include "dma.h" |
11 | 59a703eb | aliguori | #include "block_int.h" |
12 | 244ab90e | aliguori | |
13 | 244ab90e | aliguori | void qemu_sglist_init(QEMUSGList *qsg, int alloc_hint) |
14 | 244ab90e | aliguori | { |
15 | 244ab90e | aliguori | qsg->sg = qemu_malloc(alloc_hint * sizeof(ScatterGatherEntry));
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16 | 244ab90e | aliguori | qsg->nsg = 0;
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17 | 244ab90e | aliguori | qsg->nalloc = alloc_hint; |
18 | 244ab90e | aliguori | qsg->size = 0;
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19 | 244ab90e | aliguori | } |
20 | 244ab90e | aliguori | |
21 | 244ab90e | aliguori | void qemu_sglist_add(QEMUSGList *qsg, target_phys_addr_t base,
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22 | 244ab90e | aliguori | target_phys_addr_t len) |
23 | 244ab90e | aliguori | { |
24 | 244ab90e | aliguori | if (qsg->nsg == qsg->nalloc) {
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25 | 244ab90e | aliguori | qsg->nalloc = 2 * qsg->nalloc + 1; |
26 | 244ab90e | aliguori | qsg->sg = qemu_realloc(qsg->sg, qsg->nalloc * sizeof(ScatterGatherEntry));
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27 | 244ab90e | aliguori | } |
28 | 244ab90e | aliguori | qsg->sg[qsg->nsg].base = base; |
29 | 244ab90e | aliguori | qsg->sg[qsg->nsg].len = len; |
30 | 244ab90e | aliguori | qsg->size += len; |
31 | 244ab90e | aliguori | ++qsg->nsg; |
32 | 244ab90e | aliguori | } |
33 | 244ab90e | aliguori | |
34 | 244ab90e | aliguori | void qemu_sglist_destroy(QEMUSGList *qsg)
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35 | 244ab90e | aliguori | { |
36 | 244ab90e | aliguori | qemu_free(qsg->sg); |
37 | 244ab90e | aliguori | } |
38 | 244ab90e | aliguori | |
39 | 59a703eb | aliguori | typedef struct { |
40 | 59a703eb | aliguori | BlockDriverState *bs; |
41 | 59a703eb | aliguori | BlockDriverAIOCB *acb; |
42 | 59a703eb | aliguori | QEMUSGList *sg; |
43 | 59a703eb | aliguori | uint64_t sector_num; |
44 | 59a703eb | aliguori | int is_write;
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45 | 59a703eb | aliguori | int sg_cur_index;
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46 | 59a703eb | aliguori | target_phys_addr_t sg_cur_byte; |
47 | 59a703eb | aliguori | QEMUIOVector iov; |
48 | 59a703eb | aliguori | QEMUBH *bh; |
49 | 59a703eb | aliguori | } DMABlockState; |
50 | 59a703eb | aliguori | |
51 | 59a703eb | aliguori | static void dma_bdrv_cb(void *opaque, int ret); |
52 | 59a703eb | aliguori | |
53 | 59a703eb | aliguori | static void reschedule_dma(void *opaque) |
54 | 59a703eb | aliguori | { |
55 | 59a703eb | aliguori | DMABlockState *dbs = (DMABlockState *)opaque; |
56 | 59a703eb | aliguori | |
57 | 59a703eb | aliguori | qemu_bh_delete(dbs->bh); |
58 | 59a703eb | aliguori | dbs->bh = NULL;
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59 | 59a703eb | aliguori | dma_bdrv_cb(opaque, 0);
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60 | 59a703eb | aliguori | } |
61 | 59a703eb | aliguori | |
62 | 59a703eb | aliguori | static void continue_after_map_failure(void *opaque) |
63 | 59a703eb | aliguori | { |
64 | 59a703eb | aliguori | DMABlockState *dbs = (DMABlockState *)opaque; |
65 | 59a703eb | aliguori | |
66 | 59a703eb | aliguori | dbs->bh = qemu_bh_new(reschedule_dma, dbs); |
67 | 59a703eb | aliguori | qemu_bh_schedule(dbs->bh); |
68 | 59a703eb | aliguori | } |
69 | 59a703eb | aliguori | |
70 | 59a703eb | aliguori | static void dma_bdrv_cb(void *opaque, int ret) |
71 | 59a703eb | aliguori | { |
72 | 59a703eb | aliguori | DMABlockState *dbs = (DMABlockState *)opaque; |
73 | 59a703eb | aliguori | target_phys_addr_t cur_addr, cur_len; |
74 | 59a703eb | aliguori | void *mem;
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75 | 59a703eb | aliguori | int i;
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76 | 59a703eb | aliguori | |
77 | 59a703eb | aliguori | dbs->sector_num += dbs->iov.size / 512;
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78 | 59a703eb | aliguori | for (i = 0; i < dbs->iov.niov; ++i) { |
79 | 59a703eb | aliguori | cpu_physical_memory_unmap(dbs->iov.iov[i].iov_base, |
80 | 59a703eb | aliguori | dbs->iov.iov[i].iov_len, !dbs->is_write, |
81 | 59a703eb | aliguori | dbs->iov.iov[i].iov_len); |
82 | 59a703eb | aliguori | } |
83 | 59a703eb | aliguori | qemu_iovec_reset(&dbs->iov); |
84 | 59a703eb | aliguori | |
85 | 59a703eb | aliguori | if (dbs->sg_cur_index == dbs->sg->nsg || ret < 0) { |
86 | 59a703eb | aliguori | dbs->acb->cb(dbs->acb->opaque, ret); |
87 | 59a703eb | aliguori | qemu_iovec_destroy(&dbs->iov); |
88 | 59a703eb | aliguori | qemu_aio_release(dbs->acb); |
89 | 59a703eb | aliguori | qemu_free(dbs); |
90 | 59a703eb | aliguori | return;
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91 | 59a703eb | aliguori | } |
92 | 59a703eb | aliguori | |
93 | 59a703eb | aliguori | while (dbs->sg_cur_index < dbs->sg->nsg) {
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94 | 59a703eb | aliguori | cur_addr = dbs->sg->sg[dbs->sg_cur_index].base + dbs->sg_cur_byte; |
95 | 59a703eb | aliguori | cur_len = dbs->sg->sg[dbs->sg_cur_index].len - dbs->sg_cur_byte; |
96 | 59a703eb | aliguori | mem = cpu_physical_memory_map(cur_addr, &cur_len, !dbs->is_write); |
97 | 59a703eb | aliguori | if (!mem)
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98 | 59a703eb | aliguori | break;
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99 | 59a703eb | aliguori | qemu_iovec_add(&dbs->iov, mem, cur_len); |
100 | 59a703eb | aliguori | dbs->sg_cur_byte += cur_len; |
101 | 59a703eb | aliguori | if (dbs->sg_cur_byte == dbs->sg->sg[dbs->sg_cur_index].len) {
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102 | 59a703eb | aliguori | dbs->sg_cur_byte = 0;
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103 | 59a703eb | aliguori | ++dbs->sg_cur_index; |
104 | 59a703eb | aliguori | } |
105 | 59a703eb | aliguori | } |
106 | 59a703eb | aliguori | |
107 | 59a703eb | aliguori | if (dbs->iov.size == 0) { |
108 | 59a703eb | aliguori | cpu_register_map_client(dbs, continue_after_map_failure); |
109 | 59a703eb | aliguori | return;
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110 | 59a703eb | aliguori | } |
111 | 59a703eb | aliguori | |
112 | 59a703eb | aliguori | if (dbs->is_write) {
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113 | 59a703eb | aliguori | bdrv_aio_writev(dbs->bs, dbs->sector_num, &dbs->iov, |
114 | 59a703eb | aliguori | dbs->iov.size / 512, dma_bdrv_cb, dbs);
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115 | 59a703eb | aliguori | } else {
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116 | 59a703eb | aliguori | bdrv_aio_readv(dbs->bs, dbs->sector_num, &dbs->iov, |
117 | 59a703eb | aliguori | dbs->iov.size / 512, dma_bdrv_cb, dbs);
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118 | 59a703eb | aliguori | } |
119 | 59a703eb | aliguori | } |
120 | 59a703eb | aliguori | |
121 | 59a703eb | aliguori | static BlockDriverAIOCB *dma_bdrv_io(
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122 | 59a703eb | aliguori | BlockDriverState *bs, QEMUSGList *sg, uint64_t sector_num, |
123 | 59a703eb | aliguori | BlockDriverCompletionFunc *cb, void *opaque,
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124 | 59a703eb | aliguori | int is_write)
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125 | 59a703eb | aliguori | { |
126 | 59a703eb | aliguori | DMABlockState *dbs = qemu_malloc(sizeof(*dbs));
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127 | 59a703eb | aliguori | |
128 | 59a703eb | aliguori | dbs->bs = bs; |
129 | 59a703eb | aliguori | dbs->acb = qemu_aio_get(bs, cb, opaque); |
130 | 59a703eb | aliguori | dbs->sg = sg; |
131 | 59a703eb | aliguori | dbs->sector_num = sector_num; |
132 | 59a703eb | aliguori | dbs->sg_cur_index = 0;
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133 | 59a703eb | aliguori | dbs->sg_cur_byte = 0;
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134 | 59a703eb | aliguori | dbs->is_write = is_write; |
135 | 59a703eb | aliguori | dbs->bh = NULL;
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136 | 59a703eb | aliguori | qemu_iovec_init(&dbs->iov, sg->nsg); |
137 | 59a703eb | aliguori | dma_bdrv_cb(dbs, 0);
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138 | 59a703eb | aliguori | return dbs->acb;
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139 | 59a703eb | aliguori | } |
140 | 59a703eb | aliguori | |
141 | 59a703eb | aliguori | |
142 | 59a703eb | aliguori | BlockDriverAIOCB *dma_bdrv_read(BlockDriverState *bs, |
143 | 59a703eb | aliguori | QEMUSGList *sg, uint64_t sector, |
144 | 59a703eb | aliguori | void (*cb)(void *opaque, int ret), void *opaque) |
145 | 59a703eb | aliguori | { |
146 | 59a703eb | aliguori | return dma_bdrv_io(bs, sg, sector, cb, opaque, 0); |
147 | 59a703eb | aliguori | } |
148 | 59a703eb | aliguori | |
149 | 59a703eb | aliguori | BlockDriverAIOCB *dma_bdrv_write(BlockDriverState *bs, |
150 | 59a703eb | aliguori | QEMUSGList *sg, uint64_t sector, |
151 | 59a703eb | aliguori | void (*cb)(void *opaque, int ret), void *opaque) |
152 | 59a703eb | aliguori | { |
153 | 59a703eb | aliguori | return dma_bdrv_io(bs, sg, sector, cb, opaque, 1); |
154 | 59a703eb | aliguori | } |