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 blk_get_geometry(BlockBackend *blk, uint64_t *nb_sectors_ptr);
74 
75 int64_t coroutine_fn blk_co_nb_sectors(BlockBackend *blk);
76 int64_t co_wrapper_mixed blk_nb_sectors(BlockBackend *blk);
77 
78 void *blk_try_blockalign(BlockBackend *blk, size_t size);
79 void *blk_blockalign(BlockBackend *blk, size_t size);
80 bool blk_is_writable(BlockBackend *blk);
81 bool blk_enable_write_cache(BlockBackend *blk);
82 BlockdevOnError blk_get_on_error(BlockBackend *blk, bool is_read);
83 BlockErrorAction blk_get_error_action(BlockBackend *blk, bool is_read,
84                                       int error);
85 void blk_error_action(BlockBackend *blk, BlockErrorAction action,
86                       bool is_read, int error);
87 void blk_iostatus_set_err(BlockBackend *blk, int error);
88 int blk_get_max_iov(BlockBackend *blk);
89 int blk_get_max_hw_iov(BlockBackend *blk);
90 
91 void coroutine_fn blk_co_io_plug(BlockBackend *blk);
92 void co_wrapper blk_io_plug(BlockBackend *blk);
93 
94 void coroutine_fn blk_co_io_unplug(BlockBackend *blk);
95 void co_wrapper blk_io_unplug(BlockBackend *blk);
96 
97 AioContext *blk_get_aio_context(BlockBackend *blk);
98 BlockAcctStats *blk_get_stats(BlockBackend *blk);
99 void *blk_aio_get(const AIOCBInfo *aiocb_info, BlockBackend *blk,
100                   BlockCompletionFunc *cb, void *opaque);
101 BlockAIOCB *blk_abort_aio_request(BlockBackend *blk,
102                                   BlockCompletionFunc *cb,
103                                   void *opaque, int ret);
104 
105 uint32_t blk_get_request_alignment(BlockBackend *blk);
106 uint32_t blk_get_max_transfer(BlockBackend *blk);
107 uint64_t blk_get_max_hw_transfer(BlockBackend *blk);
108 
109 int coroutine_fn blk_co_copy_range(BlockBackend *blk_in, int64_t off_in,
110                                    BlockBackend *blk_out, int64_t off_out,
111                                    int64_t bytes, BdrvRequestFlags read_flags,
112                                    BdrvRequestFlags write_flags);
113 
114 int coroutine_fn blk_co_block_status_above(BlockBackend *blk,
115                                            BlockDriverState *base,
116                                            int64_t offset, int64_t bytes,
117                                            int64_t *pnum, int64_t *map,
118                                            BlockDriverState **file);
119 int coroutine_fn blk_co_is_allocated_above(BlockBackend *blk,
120                                            BlockDriverState *base,
121                                            bool include_base, int64_t offset,
122                                            int64_t bytes, int64_t *pnum);
123 
124 /*
125  * "I/O or GS" API functions. These functions can run without
126  * the BQL, but only in one specific iothread/main loop.
127  *
128  * See include/block/block-io.h for more information about
129  * the "I/O or GS" API.
130  */
131 
132 int co_wrapper_mixed blk_pread(BlockBackend *blk, int64_t offset,
133                                int64_t bytes, void *buf,
134                                BdrvRequestFlags flags);
135 int coroutine_fn blk_co_pread(BlockBackend *blk, int64_t offset, int64_t bytes,
136                               void *buf, BdrvRequestFlags flags);
137 
138 int co_wrapper_mixed blk_preadv(BlockBackend *blk, int64_t offset,
139                                 int64_t bytes, QEMUIOVector *qiov,
140                                 BdrvRequestFlags flags);
141 int coroutine_fn blk_co_preadv(BlockBackend *blk, int64_t offset,
142                                int64_t bytes, QEMUIOVector *qiov,
143                                BdrvRequestFlags flags);
144 
145 int co_wrapper_mixed blk_preadv_part(BlockBackend *blk, int64_t offset,
146                                      int64_t bytes, QEMUIOVector *qiov,
147                                      size_t qiov_offset,
148                                      BdrvRequestFlags flags);
149 int coroutine_fn blk_co_preadv_part(BlockBackend *blk, int64_t offset,
150                                     int64_t bytes, QEMUIOVector *qiov,
151                                     size_t qiov_offset, BdrvRequestFlags flags);
152 
153 int co_wrapper_mixed blk_pwrite(BlockBackend *blk, int64_t offset,
154                                 int64_t bytes, const void *buf,
155                                 BdrvRequestFlags flags);
156 int coroutine_fn blk_co_pwrite(BlockBackend *blk, int64_t offset, int64_t bytes,
157                                const void *buf, BdrvRequestFlags flags);
158 
159 int co_wrapper_mixed blk_pwritev(BlockBackend *blk, int64_t offset,
160                                  int64_t bytes, QEMUIOVector *qiov,
161                                  BdrvRequestFlags flags);
162 int coroutine_fn blk_co_pwritev(BlockBackend *blk, int64_t offset,
163                                 int64_t bytes, QEMUIOVector *qiov,
164                                 BdrvRequestFlags flags);
165 
166 int co_wrapper_mixed blk_pwritev_part(BlockBackend *blk, int64_t offset,
167                                       int64_t bytes, QEMUIOVector *qiov,
168                                       size_t qiov_offset,
169                                       BdrvRequestFlags flags);
170 int coroutine_fn blk_co_pwritev_part(BlockBackend *blk, int64_t offset,
171                                      int64_t bytes,
172                                      QEMUIOVector *qiov, size_t qiov_offset,
173                                      BdrvRequestFlags flags);
174 
175 int co_wrapper_mixed blk_pwrite_compressed(BlockBackend *blk,
176                                            int64_t offset, int64_t bytes,
177                                            const void *buf);
178 int coroutine_fn blk_co_pwrite_compressed(BlockBackend *blk, int64_t offset,
179                                           int64_t bytes, const void *buf);
180 
181 int co_wrapper_mixed blk_pwrite_zeroes(BlockBackend *blk, int64_t offset,
182                                        int64_t bytes,
183                                        BdrvRequestFlags flags);
184 int coroutine_fn blk_co_pwrite_zeroes(BlockBackend *blk, int64_t offset,
185                                       int64_t bytes, BdrvRequestFlags flags);
186 
187 int co_wrapper_mixed blk_pdiscard(BlockBackend *blk, int64_t offset,
188                                   int64_t bytes);
189 int coroutine_fn blk_co_pdiscard(BlockBackend *blk, int64_t offset,
190                                  int64_t bytes);
191 
192 int co_wrapper_mixed blk_flush(BlockBackend *blk);
193 int coroutine_fn blk_co_flush(BlockBackend *blk);
194 
195 int co_wrapper_mixed blk_ioctl(BlockBackend *blk, unsigned long int req,
196                                void *buf);
197 int coroutine_fn blk_co_ioctl(BlockBackend *blk, unsigned long int req,
198                               void *buf);
199 
200 int co_wrapper_mixed blk_truncate(BlockBackend *blk, int64_t offset,
201                                   bool exact, PreallocMode prealloc,
202                                   BdrvRequestFlags flags, Error **errp);
203 int coroutine_fn blk_co_truncate(BlockBackend *blk, int64_t offset, bool exact,
204                                  PreallocMode prealloc, BdrvRequestFlags flags,
205                                  Error **errp);
206 
207 #endif /* BLOCK_BACKEND_IO_H */
208