1 /*
2  * QEMU Block backends
3  *
4  * Copyright (C) 2014-2016 Red Hat, Inc.
5  *
6  * Authors:
7  *  Markus Armbruster <armbru@redhat.com>,
8  *
9  * This work is licensed under the terms of the GNU LGPL, version 2.1
10  * or later.  See the COPYING.LIB file in the top-level directory.
11  */
12 
13 #ifndef BLOCK_BACKEND_IO_H
14 #define BLOCK_BACKEND_IO_H
15 
16 #include "block-backend-common.h"
17 #include "block/accounting.h"
18 
19 /*
20  * I/O API functions. These functions are thread-safe.
21  *
22  * See include/block/block-io.h for more information about
23  * the I/O API.
24  */
25 
26 const char *blk_name(const BlockBackend *blk);
27 
28 BlockDriverState *blk_bs(BlockBackend *blk);
29 
30 void blk_set_allow_write_beyond_eof(BlockBackend *blk, bool allow);
31 void blk_set_allow_aio_context_change(BlockBackend *blk, bool allow);
32 void blk_set_disable_request_queuing(BlockBackend *blk, bool disable);
33 bool blk_iostatus_is_enabled(const BlockBackend *blk);
34 
35 char *blk_get_attached_dev_id(BlockBackend *blk);
36 
37 BlockAIOCB *blk_aio_pwrite_zeroes(BlockBackend *blk, int64_t offset,
38                                   int64_t bytes, BdrvRequestFlags flags,
39                                   BlockCompletionFunc *cb, void *opaque);
40 
41 BlockAIOCB *blk_aio_preadv(BlockBackend *blk, int64_t offset,
42                            QEMUIOVector *qiov, BdrvRequestFlags flags,
43                            BlockCompletionFunc *cb, void *opaque);
44 BlockAIOCB *blk_aio_pwritev(BlockBackend *blk, int64_t offset,
45                             QEMUIOVector *qiov, BdrvRequestFlags flags,
46                             BlockCompletionFunc *cb, void *opaque);
47 BlockAIOCB *blk_aio_flush(BlockBackend *blk,
48                           BlockCompletionFunc *cb, void *opaque);
49 BlockAIOCB *blk_aio_pdiscard(BlockBackend *blk, int64_t offset, int64_t bytes,
50                              BlockCompletionFunc *cb, void *opaque);
51 void blk_aio_cancel_async(BlockAIOCB *acb);
52 BlockAIOCB *blk_aio_ioctl(BlockBackend *blk, unsigned long int req, void *buf,
53                           BlockCompletionFunc *cb, void *opaque);
54 
55 void blk_inc_in_flight(BlockBackend *blk);
56 void blk_dec_in_flight(BlockBackend *blk);
57 
58 bool coroutine_fn GRAPH_RDLOCK blk_co_is_inserted(BlockBackend *blk);
59 bool co_wrapper_mixed_bdrv_rdlock blk_is_inserted(BlockBackend *blk);
60 
61 bool coroutine_fn GRAPH_RDLOCK blk_co_is_available(BlockBackend *blk);
62 bool co_wrapper_mixed_bdrv_rdlock blk_is_available(BlockBackend *blk);
63 
64 void coroutine_fn blk_co_lock_medium(BlockBackend *blk, bool locked);
65 void co_wrapper blk_lock_medium(BlockBackend *blk, bool locked);
66 
67 void coroutine_fn blk_co_eject(BlockBackend *blk, bool eject_flag);
68 void co_wrapper blk_eject(BlockBackend *blk, bool eject_flag);
69 
70 int64_t coroutine_fn blk_co_getlength(BlockBackend *blk);
71 int64_t co_wrapper_mixed blk_getlength(BlockBackend *blk);
72 
73 void coroutine_fn blk_co_get_geometry(BlockBackend *blk,
74                                       uint64_t *nb_sectors_ptr);
75 void blk_get_geometry(BlockBackend *blk, uint64_t *nb_sectors_ptr);
76 
77 int64_t coroutine_fn blk_co_nb_sectors(BlockBackend *blk);
78 int64_t blk_nb_sectors(BlockBackend *blk);
79 
80 void *blk_try_blockalign(BlockBackend *blk, size_t size);
81 void *blk_blockalign(BlockBackend *blk, size_t size);
82 bool blk_is_writable(BlockBackend *blk);
83 bool blk_enable_write_cache(BlockBackend *blk);
84 BlockdevOnError blk_get_on_error(BlockBackend *blk, bool is_read);
85 BlockErrorAction blk_get_error_action(BlockBackend *blk, bool is_read,
86                                       int error);
87 void blk_error_action(BlockBackend *blk, BlockErrorAction action,
88                       bool is_read, int error);
89 void blk_iostatus_set_err(BlockBackend *blk, int error);
90 int blk_get_max_iov(BlockBackend *blk);
91 int blk_get_max_hw_iov(BlockBackend *blk);
92 
93 void coroutine_fn blk_co_io_plug(BlockBackend *blk);
94 void co_wrapper blk_io_plug(BlockBackend *blk);
95 
96 void coroutine_fn blk_co_io_unplug(BlockBackend *blk);
97 void co_wrapper blk_io_unplug(BlockBackend *blk);
98 
99 AioContext *blk_get_aio_context(BlockBackend *blk);
100 BlockAcctStats *blk_get_stats(BlockBackend *blk);
101 void *blk_aio_get(const AIOCBInfo *aiocb_info, BlockBackend *blk,
102                   BlockCompletionFunc *cb, void *opaque);
103 BlockAIOCB *blk_abort_aio_request(BlockBackend *blk,
104                                   BlockCompletionFunc *cb,
105                                   void *opaque, int ret);
106 
107 uint32_t blk_get_request_alignment(BlockBackend *blk);
108 uint32_t blk_get_max_transfer(BlockBackend *blk);
109 uint64_t blk_get_max_hw_transfer(BlockBackend *blk);
110 
111 int coroutine_fn blk_co_copy_range(BlockBackend *blk_in, int64_t off_in,
112                                    BlockBackend *blk_out, int64_t off_out,
113                                    int64_t bytes, BdrvRequestFlags read_flags,
114                                    BdrvRequestFlags write_flags);
115 
116 int coroutine_fn blk_co_block_status_above(BlockBackend *blk,
117                                            BlockDriverState *base,
118                                            int64_t offset, int64_t bytes,
119                                            int64_t *pnum, int64_t *map,
120                                            BlockDriverState **file);
121 int coroutine_fn blk_co_is_allocated_above(BlockBackend *blk,
122                                            BlockDriverState *base,
123                                            bool include_base, int64_t offset,
124                                            int64_t bytes, int64_t *pnum);
125 
126 /*
127  * "I/O or GS" API functions. These functions can run without
128  * the BQL, but only in one specific iothread/main loop.
129  *
130  * See include/block/block-io.h for more information about
131  * the "I/O or GS" API.
132  */
133 
134 int co_wrapper_mixed blk_pread(BlockBackend *blk, int64_t offset,
135                                int64_t bytes, void *buf,
136                                BdrvRequestFlags flags);
137 int coroutine_fn blk_co_pread(BlockBackend *blk, int64_t offset, int64_t bytes,
138                               void *buf, BdrvRequestFlags flags);
139 
140 int co_wrapper_mixed blk_preadv(BlockBackend *blk, int64_t offset,
141                                 int64_t bytes, QEMUIOVector *qiov,
142                                 BdrvRequestFlags flags);
143 int coroutine_fn blk_co_preadv(BlockBackend *blk, int64_t offset,
144                                int64_t bytes, QEMUIOVector *qiov,
145                                BdrvRequestFlags flags);
146 
147 int co_wrapper_mixed blk_preadv_part(BlockBackend *blk, int64_t offset,
148                                      int64_t bytes, QEMUIOVector *qiov,
149                                      size_t qiov_offset,
150                                      BdrvRequestFlags flags);
151 int coroutine_fn blk_co_preadv_part(BlockBackend *blk, int64_t offset,
152                                     int64_t bytes, QEMUIOVector *qiov,
153                                     size_t qiov_offset, BdrvRequestFlags flags);
154 
155 int co_wrapper_mixed blk_pwrite(BlockBackend *blk, int64_t offset,
156                                 int64_t bytes, const void *buf,
157                                 BdrvRequestFlags flags);
158 int coroutine_fn blk_co_pwrite(BlockBackend *blk, int64_t offset, int64_t bytes,
159                                const void *buf, BdrvRequestFlags flags);
160 
161 int co_wrapper_mixed blk_pwritev(BlockBackend *blk, int64_t offset,
162                                  int64_t bytes, QEMUIOVector *qiov,
163                                  BdrvRequestFlags flags);
164 int coroutine_fn blk_co_pwritev(BlockBackend *blk, int64_t offset,
165                                 int64_t bytes, QEMUIOVector *qiov,
166                                 BdrvRequestFlags flags);
167 
168 int co_wrapper_mixed blk_pwritev_part(BlockBackend *blk, int64_t offset,
169                                       int64_t bytes, QEMUIOVector *qiov,
170                                       size_t qiov_offset,
171                                       BdrvRequestFlags flags);
172 int coroutine_fn blk_co_pwritev_part(BlockBackend *blk, int64_t offset,
173                                      int64_t bytes,
174                                      QEMUIOVector *qiov, size_t qiov_offset,
175                                      BdrvRequestFlags flags);
176 
177 int co_wrapper_mixed blk_pwrite_compressed(BlockBackend *blk,
178                                            int64_t offset, int64_t bytes,
179                                            const void *buf);
180 int coroutine_fn blk_co_pwrite_compressed(BlockBackend *blk, int64_t offset,
181                                           int64_t bytes, const void *buf);
182 
183 int co_wrapper_mixed blk_pwrite_zeroes(BlockBackend *blk, int64_t offset,
184                                        int64_t bytes,
185                                        BdrvRequestFlags flags);
186 int coroutine_fn blk_co_pwrite_zeroes(BlockBackend *blk, int64_t offset,
187                                       int64_t bytes, BdrvRequestFlags flags);
188 
189 int co_wrapper_mixed blk_pdiscard(BlockBackend *blk, int64_t offset,
190                                   int64_t bytes);
191 int coroutine_fn blk_co_pdiscard(BlockBackend *blk, int64_t offset,
192                                  int64_t bytes);
193 
194 int co_wrapper_mixed blk_flush(BlockBackend *blk);
195 int coroutine_fn blk_co_flush(BlockBackend *blk);
196 
197 int co_wrapper_mixed blk_ioctl(BlockBackend *blk, unsigned long int req,
198                                void *buf);
199 int coroutine_fn blk_co_ioctl(BlockBackend *blk, unsigned long int req,
200                               void *buf);
201 
202 int co_wrapper_mixed blk_truncate(BlockBackend *blk, int64_t offset,
203                                   bool exact, PreallocMode prealloc,
204                                   BdrvRequestFlags flags, Error **errp);
205 int coroutine_fn blk_co_truncate(BlockBackend *blk, int64_t offset, bool exact,
206                                  PreallocMode prealloc, BdrvRequestFlags flags,
207                                  Error **errp);
208 
209 #endif /* BLOCK_BACKEND_IO_H */
210