xref: /openbmc/qemu/include/sysemu/block-backend.h (revision 14b6d44d)
1 /*
2  * QEMU Block backends
3  *
4  * Copyright (C) 2014 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_H
14 #define BLOCK_BACKEND_H
15 
16 /*
17  * TODO Have to include block/block.h for a bunch of block layer
18  * types.  Unfortunately, this pulls in the whole BlockDriverState
19  * API, which we don't want used by many BlockBackend users.  Some of
20  * the types belong here, and the rest should be split into a common
21  * header and one for the BlockDriverState API.
22  */
23 #include "block/block.h"
24 
25 /* Callbacks for block device models */
26 typedef struct BlockDevOps {
27     /*
28      * Runs when virtual media changed (monitor commands eject, change)
29      * Argument load is true on load and false on eject.
30      * Beware: doesn't run when a host device's physical media
31      * changes.  Sure would be useful if it did.
32      * Device models with removable media must implement this callback.
33      */
34     void (*change_media_cb)(void *opaque, bool load);
35     /*
36      * Runs when an eject request is issued from the monitor, the tray
37      * is closed, and the medium is locked.
38      * Device models that do not implement is_medium_locked will not need
39      * this callback.  Device models that can lock the medium or tray might
40      * want to implement the callback and unlock the tray when "force" is
41      * true, even if they do not support eject requests.
42      */
43     void (*eject_request_cb)(void *opaque, bool force);
44     /*
45      * Is the virtual tray open?
46      * Device models implement this only when the device has a tray.
47      */
48     bool (*is_tray_open)(void *opaque);
49     /*
50      * Is the virtual medium locked into the device?
51      * Device models implement this only when device has such a lock.
52      */
53     bool (*is_medium_locked)(void *opaque);
54     /*
55      * Runs when the size changed (e.g. monitor command block_resize)
56      */
57     void (*resize_cb)(void *opaque);
58 } BlockDevOps;
59 
60 BlockBackend *blk_new(Error **errp);
61 BlockBackend *blk_new_with_bs(Error **errp);
62 BlockBackend *blk_new_open(const char *filename, const char *reference,
63                            QDict *options, int flags, Error **errp);
64 int blk_get_refcnt(BlockBackend *blk);
65 void blk_ref(BlockBackend *blk);
66 void blk_unref(BlockBackend *blk);
67 void blk_remove_all_bs(void);
68 const char *blk_name(BlockBackend *blk);
69 BlockBackend *blk_by_name(const char *name);
70 BlockBackend *blk_next(BlockBackend *blk);
71 BlockDriverState *blk_next_root_bs(BlockDriverState *bs);
72 bool monitor_add_blk(BlockBackend *blk, const char *name, Error **errp);
73 void monitor_remove_blk(BlockBackend *blk);
74 
75 BlockDriverState *blk_bs(BlockBackend *blk);
76 void blk_remove_bs(BlockBackend *blk);
77 void blk_insert_bs(BlockBackend *blk, BlockDriverState *bs);
78 
79 void blk_set_allow_write_beyond_eof(BlockBackend *blk, bool allow);
80 void blk_iostatus_enable(BlockBackend *blk);
81 bool blk_iostatus_is_enabled(const BlockBackend *blk);
82 BlockDeviceIoStatus blk_iostatus(const BlockBackend *blk);
83 void blk_iostatus_disable(BlockBackend *blk);
84 void blk_iostatus_reset(BlockBackend *blk);
85 void blk_iostatus_set_err(BlockBackend *blk, int error);
86 int blk_attach_dev(BlockBackend *blk, void *dev);
87 void blk_attach_dev_nofail(BlockBackend *blk, void *dev);
88 void blk_detach_dev(BlockBackend *blk, void *dev);
89 void *blk_get_attached_dev(BlockBackend *blk);
90 void blk_set_dev_ops(BlockBackend *blk, const BlockDevOps *ops, void *opaque);
91 int blk_read(BlockBackend *blk, int64_t sector_num, uint8_t *buf,
92              int nb_sectors);
93 int blk_read_unthrottled(BlockBackend *blk, int64_t sector_num, uint8_t *buf,
94                          int nb_sectors);
95 int blk_write(BlockBackend *blk, int64_t sector_num, const uint8_t *buf,
96               int nb_sectors);
97 int blk_write_zeroes(BlockBackend *blk, int64_t sector_num,
98                      int nb_sectors, BdrvRequestFlags flags);
99 BlockAIOCB *blk_aio_write_zeroes(BlockBackend *blk, int64_t sector_num,
100                                  int nb_sectors, BdrvRequestFlags flags,
101                                  BlockCompletionFunc *cb, void *opaque);
102 int blk_pread(BlockBackend *blk, int64_t offset, void *buf, int count);
103 int blk_pwrite(BlockBackend *blk, int64_t offset, const void *buf, int count);
104 int64_t blk_getlength(BlockBackend *blk);
105 void blk_get_geometry(BlockBackend *blk, uint64_t *nb_sectors_ptr);
106 int64_t blk_nb_sectors(BlockBackend *blk);
107 BlockAIOCB *blk_aio_readv(BlockBackend *blk, int64_t sector_num,
108                           QEMUIOVector *iov, int nb_sectors,
109                           BlockCompletionFunc *cb, void *opaque);
110 BlockAIOCB *blk_aio_writev(BlockBackend *blk, int64_t sector_num,
111                            QEMUIOVector *iov, int nb_sectors,
112                            BlockCompletionFunc *cb, void *opaque);
113 BlockAIOCB *blk_aio_flush(BlockBackend *blk,
114                           BlockCompletionFunc *cb, void *opaque);
115 BlockAIOCB *blk_aio_discard(BlockBackend *blk,
116                             int64_t sector_num, int nb_sectors,
117                             BlockCompletionFunc *cb, void *opaque);
118 void blk_aio_cancel(BlockAIOCB *acb);
119 void blk_aio_cancel_async(BlockAIOCB *acb);
120 int blk_aio_multiwrite(BlockBackend *blk, BlockRequest *reqs, int num_reqs);
121 int blk_ioctl(BlockBackend *blk, unsigned long int req, void *buf);
122 BlockAIOCB *blk_aio_ioctl(BlockBackend *blk, unsigned long int req, void *buf,
123                           BlockCompletionFunc *cb, void *opaque);
124 int blk_co_discard(BlockBackend *blk, int64_t sector_num, int nb_sectors);
125 int blk_co_flush(BlockBackend *blk);
126 int blk_flush(BlockBackend *blk);
127 int blk_flush_all(void);
128 int blk_commit_all(void);
129 void blk_drain(BlockBackend *blk);
130 void blk_drain_all(void);
131 void blk_set_on_error(BlockBackend *blk, BlockdevOnError on_read_error,
132                       BlockdevOnError on_write_error);
133 BlockdevOnError blk_get_on_error(BlockBackend *blk, bool is_read);
134 BlockErrorAction blk_get_error_action(BlockBackend *blk, bool is_read,
135                                       int error);
136 void blk_error_action(BlockBackend *blk, BlockErrorAction action,
137                       bool is_read, int error);
138 int blk_is_read_only(BlockBackend *blk);
139 int blk_is_sg(BlockBackend *blk);
140 int blk_enable_write_cache(BlockBackend *blk);
141 void blk_set_enable_write_cache(BlockBackend *blk, bool wce);
142 void blk_invalidate_cache(BlockBackend *blk, Error **errp);
143 bool blk_is_inserted(BlockBackend *blk);
144 bool blk_is_available(BlockBackend *blk);
145 void blk_lock_medium(BlockBackend *blk, bool locked);
146 void blk_eject(BlockBackend *blk, bool eject_flag);
147 int blk_get_flags(BlockBackend *blk);
148 int blk_get_max_transfer_length(BlockBackend *blk);
149 int blk_get_max_iov(BlockBackend *blk);
150 void blk_set_guest_block_size(BlockBackend *blk, int align);
151 void *blk_try_blockalign(BlockBackend *blk, size_t size);
152 void *blk_blockalign(BlockBackend *blk, size_t size);
153 bool blk_op_is_blocked(BlockBackend *blk, BlockOpType op, Error **errp);
154 void blk_op_unblock(BlockBackend *blk, BlockOpType op, Error *reason);
155 void blk_op_block_all(BlockBackend *blk, Error *reason);
156 void blk_op_unblock_all(BlockBackend *blk, Error *reason);
157 AioContext *blk_get_aio_context(BlockBackend *blk);
158 void blk_set_aio_context(BlockBackend *blk, AioContext *new_context);
159 void blk_add_aio_context_notifier(BlockBackend *blk,
160         void (*attached_aio_context)(AioContext *new_context, void *opaque),
161         void (*detach_aio_context)(void *opaque), void *opaque);
162 void blk_remove_aio_context_notifier(BlockBackend *blk,
163                                      void (*attached_aio_context)(AioContext *,
164                                                                   void *),
165                                      void (*detach_aio_context)(void *),
166                                      void *opaque);
167 void blk_add_remove_bs_notifier(BlockBackend *blk, Notifier *notify);
168 void blk_add_insert_bs_notifier(BlockBackend *blk, Notifier *notify);
169 void blk_io_plug(BlockBackend *blk);
170 void blk_io_unplug(BlockBackend *blk);
171 BlockAcctStats *blk_get_stats(BlockBackend *blk);
172 BlockBackendRootState *blk_get_root_state(BlockBackend *blk);
173 void blk_update_root_state(BlockBackend *blk);
174 void blk_apply_root_state(BlockBackend *blk, BlockDriverState *bs);
175 int blk_get_open_flags_from_root_state(BlockBackend *blk);
176 
177 void *blk_aio_get(const AIOCBInfo *aiocb_info, BlockBackend *blk,
178                   BlockCompletionFunc *cb, void *opaque);
179 int coroutine_fn blk_co_write_zeroes(BlockBackend *blk, int64_t sector_num,
180                                      int nb_sectors, BdrvRequestFlags flags);
181 int blk_write_compressed(BlockBackend *blk, int64_t sector_num,
182                          const uint8_t *buf, int nb_sectors);
183 int blk_truncate(BlockBackend *blk, int64_t offset);
184 int blk_discard(BlockBackend *blk, int64_t sector_num, int nb_sectors);
185 int blk_save_vmstate(BlockBackend *blk, const uint8_t *buf,
186                      int64_t pos, int size);
187 int blk_load_vmstate(BlockBackend *blk, uint8_t *buf, int64_t pos, int size);
188 int blk_probe_blocksizes(BlockBackend *blk, BlockSizes *bsz);
189 int blk_probe_geometry(BlockBackend *blk, HDGeometry *geo);
190 BlockAIOCB *blk_abort_aio_request(BlockBackend *blk,
191                                   BlockCompletionFunc *cb,
192                                   void *opaque, int ret);
193 
194 #endif
195