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aliguori244ab902009-02-05 21:23:50 +00001/*
2 * DMA helper functions
3 *
4 * Copyright (c) 2009 Red Hat
5 *
6 * This work is licensed under the terms of the GNU General Public License
7 * (GNU GPL), version 2 or later.
8 */
9
10#include "dma.h"
aliguori59a703e2009-02-05 21:23:58 +000011#include "block_int.h"
Kevin Wolfc57c4652011-11-24 06:15:28 -050012#include "trace.h"
aliguori244ab902009-02-05 21:23:50 +000013
14void qemu_sglist_init(QEMUSGList *qsg, int alloc_hint)
15{
Anthony Liguori7267c092011-08-20 22:09:37 -050016 qsg->sg = g_malloc(alloc_hint * sizeof(ScatterGatherEntry));
aliguori244ab902009-02-05 21:23:50 +000017 qsg->nsg = 0;
18 qsg->nalloc = alloc_hint;
19 qsg->size = 0;
20}
21
David Gibsond3231182011-10-31 17:06:46 +110022void qemu_sglist_add(QEMUSGList *qsg, dma_addr_t base, dma_addr_t len)
aliguori244ab902009-02-05 21:23:50 +000023{
24 if (qsg->nsg == qsg->nalloc) {
25 qsg->nalloc = 2 * qsg->nalloc + 1;
Anthony Liguori7267c092011-08-20 22:09:37 -050026 qsg->sg = g_realloc(qsg->sg, qsg->nalloc * sizeof(ScatterGatherEntry));
aliguori244ab902009-02-05 21:23:50 +000027 }
28 qsg->sg[qsg->nsg].base = base;
29 qsg->sg[qsg->nsg].len = len;
30 qsg->size += len;
31 ++qsg->nsg;
32}
33
34void qemu_sglist_destroy(QEMUSGList *qsg)
35{
Anthony Liguori7267c092011-08-20 22:09:37 -050036 g_free(qsg->sg);
aliguori244ab902009-02-05 21:23:50 +000037}
38
aliguori59a703e2009-02-05 21:23:58 +000039typedef struct {
aliguori37b78422009-03-20 18:26:16 +000040 BlockDriverAIOCB common;
aliguori59a703e2009-02-05 21:23:58 +000041 BlockDriverState *bs;
42 BlockDriverAIOCB *acb;
43 QEMUSGList *sg;
44 uint64_t sector_num;
Paolo Bonzinibbca72c2011-09-16 16:40:00 +020045 bool to_dev;
Paolo Bonzinic3adb5b2011-09-16 16:40:02 +020046 bool in_cancel;
aliguori59a703e2009-02-05 21:23:58 +000047 int sg_cur_index;
David Gibsond3231182011-10-31 17:06:46 +110048 dma_addr_t sg_cur_byte;
aliguori59a703e2009-02-05 21:23:58 +000049 QEMUIOVector iov;
50 QEMUBH *bh;
Christoph Hellwigcb144cc2011-05-19 10:57:59 +020051 DMAIOFunc *io_func;
aliguori37b78422009-03-20 18:26:16 +000052} DMAAIOCB;
aliguori59a703e2009-02-05 21:23:58 +000053
54static void dma_bdrv_cb(void *opaque, int ret);
55
56static void reschedule_dma(void *opaque)
57{
aliguori37b78422009-03-20 18:26:16 +000058 DMAAIOCB *dbs = (DMAAIOCB *)opaque;
aliguori59a703e2009-02-05 21:23:58 +000059
60 qemu_bh_delete(dbs->bh);
61 dbs->bh = NULL;
Paolo Bonzinic3adb5b2011-09-16 16:40:02 +020062 dma_bdrv_cb(dbs, 0);
aliguori59a703e2009-02-05 21:23:58 +000063}
64
65static void continue_after_map_failure(void *opaque)
66{
aliguori37b78422009-03-20 18:26:16 +000067 DMAAIOCB *dbs = (DMAAIOCB *)opaque;
aliguori59a703e2009-02-05 21:23:58 +000068
69 dbs->bh = qemu_bh_new(reschedule_dma, dbs);
70 qemu_bh_schedule(dbs->bh);
71}
72
aliguori7403b142009-03-28 16:11:25 +000073static void dma_bdrv_unmap(DMAAIOCB *dbs)
aliguori59a703e2009-02-05 21:23:58 +000074{
aliguori59a703e2009-02-05 21:23:58 +000075 int i;
76
aliguori59a703e2009-02-05 21:23:58 +000077 for (i = 0; i < dbs->iov.niov; ++i) {
78 cpu_physical_memory_unmap(dbs->iov.iov[i].iov_base,
Paolo Bonzinibbca72c2011-09-16 16:40:00 +020079 dbs->iov.iov[i].iov_len, !dbs->to_dev,
aliguori59a703e2009-02-05 21:23:58 +000080 dbs->iov.iov[i].iov_len);
81 }
Paolo Bonzinic3adb5b2011-09-16 16:40:02 +020082 qemu_iovec_reset(&dbs->iov);
83}
84
85static void dma_complete(DMAAIOCB *dbs, int ret)
86{
Kevin Wolfc57c4652011-11-24 06:15:28 -050087 trace_dma_complete(dbs, ret, dbs->common.cb);
88
Paolo Bonzinic3adb5b2011-09-16 16:40:02 +020089 dma_bdrv_unmap(dbs);
90 if (dbs->common.cb) {
91 dbs->common.cb(dbs->common.opaque, ret);
92 }
93 qemu_iovec_destroy(&dbs->iov);
94 if (dbs->bh) {
95 qemu_bh_delete(dbs->bh);
96 dbs->bh = NULL;
97 }
98 if (!dbs->in_cancel) {
99 /* Requests may complete while dma_aio_cancel is in progress. In
100 * this case, the AIOCB should not be released because it is still
101 * referenced by dma_aio_cancel. */
102 qemu_aio_release(dbs);
103 }
aliguori7403b142009-03-28 16:11:25 +0000104}
105
blueswir1856ae5c2009-04-07 17:57:09 +0000106static void dma_bdrv_cb(void *opaque, int ret)
aliguori7403b142009-03-28 16:11:25 +0000107{
108 DMAAIOCB *dbs = (DMAAIOCB *)opaque;
Anthony Liguoric227f092009-10-01 16:12:16 -0500109 target_phys_addr_t cur_addr, cur_len;
aliguori7403b142009-03-28 16:11:25 +0000110 void *mem;
111
Kevin Wolfc57c4652011-11-24 06:15:28 -0500112 trace_dma_bdrv_cb(dbs, ret);
113
aliguori7403b142009-03-28 16:11:25 +0000114 dbs->acb = NULL;
115 dbs->sector_num += dbs->iov.size / 512;
116 dma_bdrv_unmap(dbs);
aliguori59a703e2009-02-05 21:23:58 +0000117
118 if (dbs->sg_cur_index == dbs->sg->nsg || ret < 0) {
Paolo Bonzinic3adb5b2011-09-16 16:40:02 +0200119 dma_complete(dbs, ret);
aliguori59a703e2009-02-05 21:23:58 +0000120 return;
121 }
122
123 while (dbs->sg_cur_index < dbs->sg->nsg) {
124 cur_addr = dbs->sg->sg[dbs->sg_cur_index].base + dbs->sg_cur_byte;
125 cur_len = dbs->sg->sg[dbs->sg_cur_index].len - dbs->sg_cur_byte;
Paolo Bonzinibbca72c2011-09-16 16:40:00 +0200126 mem = cpu_physical_memory_map(cur_addr, &cur_len, !dbs->to_dev);
aliguori59a703e2009-02-05 21:23:58 +0000127 if (!mem)
128 break;
129 qemu_iovec_add(&dbs->iov, mem, cur_len);
130 dbs->sg_cur_byte += cur_len;
131 if (dbs->sg_cur_byte == dbs->sg->sg[dbs->sg_cur_index].len) {
132 dbs->sg_cur_byte = 0;
133 ++dbs->sg_cur_index;
134 }
135 }
136
137 if (dbs->iov.size == 0) {
Kevin Wolfc57c4652011-11-24 06:15:28 -0500138 trace_dma_map_wait(dbs);
aliguori59a703e2009-02-05 21:23:58 +0000139 cpu_register_map_client(dbs, continue_after_map_failure);
140 return;
141 }
142
Christoph Hellwigcb144cc2011-05-19 10:57:59 +0200143 dbs->acb = dbs->io_func(dbs->bs, dbs->sector_num, &dbs->iov,
144 dbs->iov.size / 512, dma_bdrv_cb, dbs);
Paolo Bonzini6bee44e2011-11-14 17:50:52 +0100145 assert(dbs->acb);
aliguori59a703e2009-02-05 21:23:58 +0000146}
147
Christoph Hellwigc16b5a22009-05-25 12:37:32 +0200148static void dma_aio_cancel(BlockDriverAIOCB *acb)
149{
150 DMAAIOCB *dbs = container_of(acb, DMAAIOCB, common);
151
Kevin Wolfc57c4652011-11-24 06:15:28 -0500152 trace_dma_aio_cancel(dbs);
153
Christoph Hellwigc16b5a22009-05-25 12:37:32 +0200154 if (dbs->acb) {
Paolo Bonzinic3adb5b2011-09-16 16:40:02 +0200155 BlockDriverAIOCB *acb = dbs->acb;
156 dbs->acb = NULL;
157 dbs->in_cancel = true;
158 bdrv_aio_cancel(acb);
159 dbs->in_cancel = false;
Christoph Hellwigc16b5a22009-05-25 12:37:32 +0200160 }
Paolo Bonzinic3adb5b2011-09-16 16:40:02 +0200161 dbs->common.cb = NULL;
162 dma_complete(dbs, 0);
Christoph Hellwigc16b5a22009-05-25 12:37:32 +0200163}
164
165static AIOPool dma_aio_pool = {
166 .aiocb_size = sizeof(DMAAIOCB),
167 .cancel = dma_aio_cancel,
168};
169
Christoph Hellwigcb144cc2011-05-19 10:57:59 +0200170BlockDriverAIOCB *dma_bdrv_io(
aliguori59a703e2009-02-05 21:23:58 +0000171 BlockDriverState *bs, QEMUSGList *sg, uint64_t sector_num,
Christoph Hellwigcb144cc2011-05-19 10:57:59 +0200172 DMAIOFunc *io_func, BlockDriverCompletionFunc *cb,
Paolo Bonzinibbca72c2011-09-16 16:40:00 +0200173 void *opaque, bool to_dev)
aliguori59a703e2009-02-05 21:23:58 +0000174{
Christoph Hellwigcb144cc2011-05-19 10:57:59 +0200175 DMAAIOCB *dbs = qemu_aio_get(&dma_aio_pool, bs, cb, opaque);
aliguori59a703e2009-02-05 21:23:58 +0000176
Kevin Wolfc57c4652011-11-24 06:15:28 -0500177 trace_dma_bdrv_io(dbs, bs, sector_num, to_dev);
178
aliguori37b78422009-03-20 18:26:16 +0000179 dbs->acb = NULL;
aliguori59a703e2009-02-05 21:23:58 +0000180 dbs->bs = bs;
aliguori59a703e2009-02-05 21:23:58 +0000181 dbs->sg = sg;
182 dbs->sector_num = sector_num;
183 dbs->sg_cur_index = 0;
184 dbs->sg_cur_byte = 0;
Paolo Bonzinibbca72c2011-09-16 16:40:00 +0200185 dbs->to_dev = to_dev;
Christoph Hellwigcb144cc2011-05-19 10:57:59 +0200186 dbs->io_func = io_func;
aliguori59a703e2009-02-05 21:23:58 +0000187 dbs->bh = NULL;
188 qemu_iovec_init(&dbs->iov, sg->nsg);
189 dma_bdrv_cb(dbs, 0);
aliguori37b78422009-03-20 18:26:16 +0000190 return &dbs->common;
aliguori59a703e2009-02-05 21:23:58 +0000191}
192
193
194BlockDriverAIOCB *dma_bdrv_read(BlockDriverState *bs,
195 QEMUSGList *sg, uint64_t sector,
196 void (*cb)(void *opaque, int ret), void *opaque)
197{
Paolo Bonzinibbca72c2011-09-16 16:40:00 +0200198 return dma_bdrv_io(bs, sg, sector, bdrv_aio_readv, cb, opaque, false);
aliguori59a703e2009-02-05 21:23:58 +0000199}
200
201BlockDriverAIOCB *dma_bdrv_write(BlockDriverState *bs,
202 QEMUSGList *sg, uint64_t sector,
203 void (*cb)(void *opaque, int ret), void *opaque)
204{
Paolo Bonzinibbca72c2011-09-16 16:40:00 +0200205 return dma_bdrv_io(bs, sg, sector, bdrv_aio_writev, cb, opaque, true);
aliguori59a703e2009-02-05 21:23:58 +0000206}