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 
18 /*
19  * I/O API functions. These functions are thread-safe.
20  *
21  * See include/block/block-io.h for more information about
22  * the I/O API.
23  */
24 
25 const char *blk_name(const BlockBackend *blk);
26 
27 BlockDriverState *blk_bs(BlockBackend *blk);
28 
29 void blk_set_allow_write_beyond_eof(BlockBackend *blk, bool allow);
30 void blk_set_allow_aio_context_change(BlockBackend *blk, bool allow);
31 void blk_set_disable_request_queuing(BlockBackend *blk, bool disable);
32 bool blk_iostatus_is_enabled(const BlockBackend *blk);
33 
34 char *blk_get_attached_dev_id(BlockBackend *blk);
35 
36 BlockAIOCB *blk_aio_pwrite_zeroes(BlockBackend *blk, int64_t offset,
37                                   int64_t bytes, BdrvRequestFlags flags,
38                                   BlockCompletionFunc *cb, void *opaque);
39 
40 BlockAIOCB *blk_aio_preadv(BlockBackend *blk, int64_t offset,
41                            QEMUIOVector *qiov, BdrvRequestFlags flags,
42                            BlockCompletionFunc *cb, void *opaque);
43 BlockAIOCB *blk_aio_pwritev(BlockBackend *blk, int64_t offset,
44                             QEMUIOVector *qiov, BdrvRequestFlags flags,
45                             BlockCompletionFunc *cb, void *opaque);
46 BlockAIOCB *blk_aio_flush(BlockBackend *blk,
47                           BlockCompletionFunc *cb, void *opaque);
48 BlockAIOCB *blk_aio_pdiscard(BlockBackend *blk, int64_t offset, int64_t bytes,
49                              BlockCompletionFunc *cb, void *opaque);
50 void blk_aio_cancel_async(BlockAIOCB *acb);
51 BlockAIOCB *blk_aio_ioctl(BlockBackend *blk, unsigned long int req, void *buf,
52                           BlockCompletionFunc *cb, void *opaque);
53 
54 void blk_inc_in_flight(BlockBackend *blk);
55 void blk_dec_in_flight(BlockBackend *blk);
56 bool blk_is_inserted(BlockBackend *blk);
57 bool blk_is_available(BlockBackend *blk);
58 void blk_lock_medium(BlockBackend *blk, bool locked);
59 void blk_eject(BlockBackend *blk, bool eject_flag);
60 int64_t blk_getlength(BlockBackend *blk);
61 void blk_get_geometry(BlockBackend *blk, uint64_t *nb_sectors_ptr);
62 int64_t blk_nb_sectors(BlockBackend *blk);
63 void *blk_try_blockalign(BlockBackend *blk, size_t size);
64 void *blk_blockalign(BlockBackend *blk, size_t size);
65 bool blk_is_writable(BlockBackend *blk);
66 bool blk_enable_write_cache(BlockBackend *blk);
67 BlockdevOnError blk_get_on_error(BlockBackend *blk, bool is_read);
68 BlockErrorAction blk_get_error_action(BlockBackend *blk, bool is_read,
69                                       int error);
70 void blk_error_action(BlockBackend *blk, BlockErrorAction action,
71                       bool is_read, int error);
72 void blk_iostatus_set_err(BlockBackend *blk, int error);
73 int blk_get_max_iov(BlockBackend *blk);
74 int blk_get_max_hw_iov(BlockBackend *blk);
75 
76 void blk_io_plug(BlockBackend *blk);
77 void blk_io_unplug(BlockBackend *blk);
78 AioContext *blk_get_aio_context(BlockBackend *blk);
79 BlockAcctStats *blk_get_stats(BlockBackend *blk);
80 void *blk_aio_get(const AIOCBInfo *aiocb_info, BlockBackend *blk,
81                   BlockCompletionFunc *cb, void *opaque);
82 BlockAIOCB *blk_abort_aio_request(BlockBackend *blk,
83                                   BlockCompletionFunc *cb,
84                                   void *opaque, int ret);
85 
86 uint32_t blk_get_request_alignment(BlockBackend *blk);
87 uint32_t blk_get_max_transfer(BlockBackend *blk);
88 uint64_t blk_get_max_hw_transfer(BlockBackend *blk);
89 
90 int coroutine_fn blk_co_copy_range(BlockBackend *blk_in, int64_t off_in,
91                                    BlockBackend *blk_out, int64_t off_out,
92                                    int64_t bytes, BdrvRequestFlags read_flags,
93                                    BdrvRequestFlags write_flags);
94 
95 
96 /*
97  * "I/O or GS" API functions. These functions can run without
98  * the BQL, but only in one specific iothread/main loop.
99  *
100  * See include/block/block-io.h for more information about
101  * the "I/O or GS" API.
102  */
103 
104 int generated_co_wrapper blk_pread(BlockBackend *blk, int64_t offset,
105                                    int64_t bytes, void *buf,
106                                    BdrvRequestFlags flags);
107 int coroutine_fn blk_co_pread(BlockBackend *blk, int64_t offset, int64_t bytes,
108                               void *buf, BdrvRequestFlags flags);
109 
110 int generated_co_wrapper blk_preadv(BlockBackend *blk, int64_t offset,
111                                     int64_t bytes, QEMUIOVector *qiov,
112                                     BdrvRequestFlags flags);
113 int coroutine_fn blk_co_preadv(BlockBackend *blk, int64_t offset,
114                                int64_t bytes, QEMUIOVector *qiov,
115                                BdrvRequestFlags flags);
116 
117 int generated_co_wrapper blk_preadv_part(BlockBackend *blk, int64_t offset,
118                                          int64_t bytes, QEMUIOVector *qiov,
119                                          size_t qiov_offset,
120                                          BdrvRequestFlags flags);
121 int coroutine_fn blk_co_preadv_part(BlockBackend *blk, int64_t offset,
122                                     int64_t bytes, QEMUIOVector *qiov,
123                                     size_t qiov_offset, BdrvRequestFlags flags);
124 
125 int generated_co_wrapper blk_pwrite(BlockBackend *blk, int64_t offset,
126                                     int64_t bytes, const void *buf,
127                                     BdrvRequestFlags flags);
128 int coroutine_fn blk_co_pwrite(BlockBackend *blk, int64_t offset, int64_t bytes,
129                                const void *buf, BdrvRequestFlags flags);
130 
131 int generated_co_wrapper blk_pwritev(BlockBackend *blk, int64_t offset,
132                                      int64_t bytes, QEMUIOVector *qiov,
133                                      BdrvRequestFlags flags);
134 int coroutine_fn blk_co_pwritev(BlockBackend *blk, int64_t offset,
135                                 int64_t bytes, QEMUIOVector *qiov,
136                                 BdrvRequestFlags flags);
137 
138 int generated_co_wrapper blk_pwritev_part(BlockBackend *blk, int64_t offset,
139                                           int64_t bytes, QEMUIOVector *qiov,
140                                           size_t qiov_offset,
141                                           BdrvRequestFlags flags);
142 int coroutine_fn blk_co_pwritev_part(BlockBackend *blk, int64_t offset,
143                                      int64_t bytes,
144                                      QEMUIOVector *qiov, size_t qiov_offset,
145                                      BdrvRequestFlags flags);
146 
147 int generated_co_wrapper blk_pwrite_compressed(BlockBackend *blk,
148                                                int64_t offset, int64_t bytes,
149                                                const void *buf);
150 int coroutine_fn blk_co_pwrite_compressed(BlockBackend *blk, int64_t offset,
151                                           int64_t bytes, const void *buf);
152 
153 int generated_co_wrapper blk_pwrite_zeroes(BlockBackend *blk, int64_t offset,
154                                            int64_t bytes,
155                                            BdrvRequestFlags flags);
156 int coroutine_fn blk_co_pwrite_zeroes(BlockBackend *blk, int64_t offset,
157                                       int64_t bytes, BdrvRequestFlags flags);
158 
159 int generated_co_wrapper blk_pdiscard(BlockBackend *blk, int64_t offset,
160                                       int64_t bytes);
161 int coroutine_fn blk_co_pdiscard(BlockBackend *blk, int64_t offset,
162                                  int64_t bytes);
163 
164 int generated_co_wrapper blk_flush(BlockBackend *blk);
165 int coroutine_fn blk_co_flush(BlockBackend *blk);
166 
167 int generated_co_wrapper blk_ioctl(BlockBackend *blk, unsigned long int req,
168                                    void *buf);
169 int coroutine_fn blk_co_ioctl(BlockBackend *blk, unsigned long int req,
170                               void *buf);
171 
172 int generated_co_wrapper blk_truncate(BlockBackend *blk, int64_t offset,
173                                       bool exact, PreallocMode prealloc,
174                                       BdrvRequestFlags flags, Error **errp);
175 int coroutine_fn blk_co_truncate(BlockBackend *blk, int64_t offset, bool exact,
176                                  PreallocMode prealloc, BdrvRequestFlags flags,
177                                  Error **errp);
178 
179 #endif /* BLOCK_BACKEND_IO_H */
180