block: throttle-groups: Use BlockBackend pointers internally
[qemu.git] / include / sysemu / block-backend.h
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_H
14 #define BLOCK_BACKEND_H
15
16 #include "qemu/iov.h"
17
18 /*
19 * TODO Have to include block/block.h for a bunch of block layer
20 * types. Unfortunately, this pulls in the whole BlockDriverState
21 * API, which we don't want used by many BlockBackend users. Some of
22 * the types belong here, and the rest should be split into a common
23 * header and one for the BlockDriverState API.
24 */
25 #include "block/block.h"
26
27 /* Callbacks for block device models */
28 typedef struct BlockDevOps {
29 /*
30 * Runs when virtual media changed (monitor commands eject, change)
31 * Argument load is true on load and false on eject.
32 * Beware: doesn't run when a host device's physical media
33 * changes. Sure would be useful if it did.
34 * Device models with removable media must implement this callback.
35 */
36 void (*change_media_cb)(void *opaque, bool load);
37 /*
38 * Runs when an eject request is issued from the monitor, the tray
39 * is closed, and the medium is locked.
40 * Device models that do not implement is_medium_locked will not need
41 * this callback. Device models that can lock the medium or tray might
42 * want to implement the callback and unlock the tray when "force" is
43 * true, even if they do not support eject requests.
44 */
45 void (*eject_request_cb)(void *opaque, bool force);
46 /*
47 * Is the virtual tray open?
48 * Device models implement this only when the device has a tray.
49 */
50 bool (*is_tray_open)(void *opaque);
51 /*
52 * Is the virtual medium locked into the device?
53 * Device models implement this only when device has such a lock.
54 */
55 bool (*is_medium_locked)(void *opaque);
56 /*
57 * Runs when the size changed (e.g. monitor command block_resize)
58 */
59 void (*resize_cb)(void *opaque);
60 } BlockDevOps;
61
62 /* This struct is embedded in (the private) BlockBackend struct and contains
63 * fields that must be public. This is in particular for QLIST_ENTRY() and
64 * friends so that BlockBackends can be kept in lists outside block-backend.c */
65 typedef struct BlockBackendPublic {
66 /* I/O throttling */
67 /* The following fields are protected by the ThrottleGroup lock.
68 * See the ThrottleGroup documentation for details. */
69 QLIST_ENTRY(BlockBackendPublic) round_robin;
70 } BlockBackendPublic;
71
72 BlockBackend *blk_new(Error **errp);
73 BlockBackend *blk_new_with_bs(Error **errp);
74 BlockBackend *blk_new_open(const char *filename, const char *reference,
75 QDict *options, int flags, Error **errp);
76 int blk_get_refcnt(BlockBackend *blk);
77 void blk_ref(BlockBackend *blk);
78 void blk_unref(BlockBackend *blk);
79 void blk_remove_all_bs(void);
80 const char *blk_name(BlockBackend *blk);
81 BlockBackend *blk_by_name(const char *name);
82 BlockBackend *blk_next(BlockBackend *blk);
83 BlockDriverState *blk_next_root_bs(BlockDriverState *bs);
84 bool monitor_add_blk(BlockBackend *blk, const char *name, Error **errp);
85 void monitor_remove_blk(BlockBackend *blk);
86
87 BlockBackendPublic *blk_get_public(BlockBackend *blk);
88 BlockBackend *blk_by_public(BlockBackendPublic *public);
89
90 BlockDriverState *blk_bs(BlockBackend *blk);
91 void blk_remove_bs(BlockBackend *blk);
92 void blk_insert_bs(BlockBackend *blk, BlockDriverState *bs);
93
94 void blk_set_allow_write_beyond_eof(BlockBackend *blk, bool allow);
95 void blk_iostatus_enable(BlockBackend *blk);
96 bool blk_iostatus_is_enabled(const BlockBackend *blk);
97 BlockDeviceIoStatus blk_iostatus(const BlockBackend *blk);
98 void blk_iostatus_disable(BlockBackend *blk);
99 void blk_iostatus_reset(BlockBackend *blk);
100 void blk_iostatus_set_err(BlockBackend *blk, int error);
101 int blk_attach_dev(BlockBackend *blk, void *dev);
102 void blk_attach_dev_nofail(BlockBackend *blk, void *dev);
103 void blk_detach_dev(BlockBackend *blk, void *dev);
104 void *blk_get_attached_dev(BlockBackend *blk);
105 void blk_set_dev_ops(BlockBackend *blk, const BlockDevOps *ops, void *opaque);
106 int blk_pread_unthrottled(BlockBackend *blk, int64_t offset, uint8_t *buf,
107 int count);
108 int blk_write_zeroes(BlockBackend *blk, int64_t offset,
109 int count, BdrvRequestFlags flags);
110 BlockAIOCB *blk_aio_write_zeroes(BlockBackend *blk, int64_t offset,
111 int count, BdrvRequestFlags flags,
112 BlockCompletionFunc *cb, void *opaque);
113 int blk_pread(BlockBackend *blk, int64_t offset, void *buf, int count);
114 int blk_pwrite(BlockBackend *blk, int64_t offset, const void *buf, int count,
115 BdrvRequestFlags flags);
116 int64_t blk_getlength(BlockBackend *blk);
117 void blk_get_geometry(BlockBackend *blk, uint64_t *nb_sectors_ptr);
118 int64_t blk_nb_sectors(BlockBackend *blk);
119 BlockAIOCB *blk_aio_preadv(BlockBackend *blk, int64_t offset,
120 QEMUIOVector *qiov, BdrvRequestFlags flags,
121 BlockCompletionFunc *cb, void *opaque);
122 BlockAIOCB *blk_aio_pwritev(BlockBackend *blk, int64_t offset,
123 QEMUIOVector *qiov, BdrvRequestFlags flags,
124 BlockCompletionFunc *cb, void *opaque);
125 BlockAIOCB *blk_aio_flush(BlockBackend *blk,
126 BlockCompletionFunc *cb, void *opaque);
127 BlockAIOCB *blk_aio_discard(BlockBackend *blk,
128 int64_t sector_num, int nb_sectors,
129 BlockCompletionFunc *cb, void *opaque);
130 void blk_aio_cancel(BlockAIOCB *acb);
131 void blk_aio_cancel_async(BlockAIOCB *acb);
132 int blk_aio_multiwrite(BlockBackend *blk, BlockRequest *reqs, int num_reqs);
133 int blk_ioctl(BlockBackend *blk, unsigned long int req, void *buf);
134 BlockAIOCB *blk_aio_ioctl(BlockBackend *blk, unsigned long int req, void *buf,
135 BlockCompletionFunc *cb, void *opaque);
136 int blk_co_discard(BlockBackend *blk, int64_t sector_num, int nb_sectors);
137 int blk_co_flush(BlockBackend *blk);
138 int blk_flush(BlockBackend *blk);
139 int blk_flush_all(void);
140 int blk_commit_all(void);
141 void blk_drain(BlockBackend *blk);
142 void blk_drain_all(void);
143 void blk_set_on_error(BlockBackend *blk, BlockdevOnError on_read_error,
144 BlockdevOnError on_write_error);
145 BlockdevOnError blk_get_on_error(BlockBackend *blk, bool is_read);
146 BlockErrorAction blk_get_error_action(BlockBackend *blk, bool is_read,
147 int error);
148 void blk_error_action(BlockBackend *blk, BlockErrorAction action,
149 bool is_read, int error);
150 int blk_is_read_only(BlockBackend *blk);
151 int blk_is_sg(BlockBackend *blk);
152 int blk_enable_write_cache(BlockBackend *blk);
153 void blk_set_enable_write_cache(BlockBackend *blk, bool wce);
154 void blk_invalidate_cache(BlockBackend *blk, Error **errp);
155 bool blk_is_inserted(BlockBackend *blk);
156 bool blk_is_available(BlockBackend *blk);
157 void blk_lock_medium(BlockBackend *blk, bool locked);
158 void blk_eject(BlockBackend *blk, bool eject_flag);
159 int blk_get_flags(BlockBackend *blk);
160 int blk_get_max_transfer_length(BlockBackend *blk);
161 int blk_get_max_iov(BlockBackend *blk);
162 void blk_set_guest_block_size(BlockBackend *blk, int align);
163 void *blk_try_blockalign(BlockBackend *blk, size_t size);
164 void *blk_blockalign(BlockBackend *blk, size_t size);
165 bool blk_op_is_blocked(BlockBackend *blk, BlockOpType op, Error **errp);
166 void blk_op_unblock(BlockBackend *blk, BlockOpType op, Error *reason);
167 void blk_op_block_all(BlockBackend *blk, Error *reason);
168 void blk_op_unblock_all(BlockBackend *blk, Error *reason);
169 AioContext *blk_get_aio_context(BlockBackend *blk);
170 void blk_set_aio_context(BlockBackend *blk, AioContext *new_context);
171 void blk_add_aio_context_notifier(BlockBackend *blk,
172 void (*attached_aio_context)(AioContext *new_context, void *opaque),
173 void (*detach_aio_context)(void *opaque), void *opaque);
174 void blk_remove_aio_context_notifier(BlockBackend *blk,
175 void (*attached_aio_context)(AioContext *,
176 void *),
177 void (*detach_aio_context)(void *),
178 void *opaque);
179 void blk_add_remove_bs_notifier(BlockBackend *blk, Notifier *notify);
180 void blk_add_insert_bs_notifier(BlockBackend *blk, Notifier *notify);
181 void blk_io_plug(BlockBackend *blk);
182 void blk_io_unplug(BlockBackend *blk);
183 BlockAcctStats *blk_get_stats(BlockBackend *blk);
184 BlockBackendRootState *blk_get_root_state(BlockBackend *blk);
185 void blk_update_root_state(BlockBackend *blk);
186 void blk_apply_root_state(BlockBackend *blk, BlockDriverState *bs);
187 int blk_get_open_flags_from_root_state(BlockBackend *blk);
188
189 void *blk_aio_get(const AIOCBInfo *aiocb_info, BlockBackend *blk,
190 BlockCompletionFunc *cb, void *opaque);
191 int coroutine_fn blk_co_write_zeroes(BlockBackend *blk, int64_t offset,
192 int count, BdrvRequestFlags flags);
193 int blk_write_compressed(BlockBackend *blk, int64_t sector_num,
194 const uint8_t *buf, int nb_sectors);
195 int blk_truncate(BlockBackend *blk, int64_t offset);
196 int blk_discard(BlockBackend *blk, int64_t sector_num, int nb_sectors);
197 int blk_save_vmstate(BlockBackend *blk, const uint8_t *buf,
198 int64_t pos, int size);
199 int blk_load_vmstate(BlockBackend *blk, uint8_t *buf, int64_t pos, int size);
200 int blk_probe_blocksizes(BlockBackend *blk, BlockSizes *bsz);
201 int blk_probe_geometry(BlockBackend *blk, HDGeometry *geo);
202 BlockAIOCB *blk_abort_aio_request(BlockBackend *blk,
203 BlockCompletionFunc *cb,
204 void *opaque, int ret);
205
206 #endif