2 * QEMU System Emulator block driver
4 * Copyright (c) 2003 Fabrice Bellard
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24 #ifndef BLOCK_GLOBAL_STATE_H
25 #define BLOCK_GLOBAL_STATE_H
27 #include "block/block-common.h"
28 #include "qemu/coroutine.h"
29 #include "qemu/transactions.h"
32 * Global state (GS) API. These functions run under the BQL.
34 * If a function modifies the graph, it also uses drain and/or
35 * aio_context_acquire/release to be sure it has unique access.
36 * aio_context locking is needed together with BQL because of
37 * the thread-safe I/O API that concurrently runs and accesses
38 * the graph without the BQL.
40 * It is important to note that not all of these functions are
41 * necessarily limited to running under the BQL, but they would
42 * require additional auditing and many small thread-safety changes
43 * to move them into the I/O API. Often it's not worth doing that
44 * work since the APIs are only used with the BQL held at the
45 * moment, so they have been placed in the GS API (for now).
47 * These functions can call any function from this and other categories
48 * (I/O, "I/O or GS", Common), but must be invoked only by other GS APIs.
50 * All functions in this header must use the macro
51 * GLOBAL_STATE_CODE();
52 * to catch when they are accidentally called without the BQL.
56 BlockDriver
*bdrv_find_protocol(const char *filename
,
57 bool allow_protocol_prefix
,
59 BlockDriver
*bdrv_find_format(const char *format_name
);
61 int coroutine_fn GRAPH_UNLOCKED
62 bdrv_co_create(BlockDriver
*drv
, const char *filename
, QemuOpts
*opts
,
65 int co_wrapper
bdrv_create(BlockDriver
*drv
, const char *filename
,
66 QemuOpts
*opts
, Error
**errp
);
68 int coroutine_fn GRAPH_UNLOCKED
69 bdrv_co_create_file(const char *filename
, QemuOpts
*opts
, Error
**errp
);
71 BlockDriverState
*bdrv_new(void);
72 int bdrv_append(BlockDriverState
*bs_new
, BlockDriverState
*bs_top
,
76 bdrv_replace_node(BlockDriverState
*from
, BlockDriverState
*to
, Error
**errp
);
78 int bdrv_replace_child_bs(BdrvChild
*child
, BlockDriverState
*new_bs
,
80 BlockDriverState
*bdrv_insert_node(BlockDriverState
*bs
, QDict
*node_options
,
81 int flags
, Error
**errp
);
82 int bdrv_drop_filter(BlockDriverState
*bs
, Error
**errp
);
84 BdrvChild
* no_coroutine_fn
85 bdrv_open_child(const char *filename
, QDict
*options
, const char *bdref_key
,
86 BlockDriverState
*parent
, const BdrvChildClass
*child_class
,
87 BdrvChildRole child_role
, bool allow_none
, Error
**errp
);
89 BdrvChild
* coroutine_fn no_co_wrapper
90 bdrv_co_open_child(const char *filename
, QDict
*options
, const char *bdref_key
,
91 BlockDriverState
*parent
, const BdrvChildClass
*child_class
,
92 BdrvChildRole child_role
, bool allow_none
, Error
**errp
);
94 int bdrv_open_file_child(const char *filename
,
95 QDict
*options
, const char *bdref_key
,
96 BlockDriverState
*parent
, Error
**errp
);
98 BlockDriverState
* no_coroutine_fn
99 bdrv_open_blockdev_ref(BlockdevRef
*ref
, Error
**errp
);
101 BlockDriverState
* coroutine_fn no_co_wrapper
102 bdrv_co_open_blockdev_ref(BlockdevRef
*ref
, Error
**errp
);
104 int bdrv_set_backing_hd(BlockDriverState
*bs
, BlockDriverState
*backing_hd
,
107 bdrv_set_backing_hd_drained(BlockDriverState
*bs
, BlockDriverState
*backing_hd
,
110 int bdrv_open_backing_file(BlockDriverState
*bs
, QDict
*parent_options
,
111 const char *bdref_key
, Error
**errp
);
113 BlockDriverState
* no_coroutine_fn
114 bdrv_open(const char *filename
, const char *reference
, QDict
*options
,
115 int flags
, Error
**errp
);
117 BlockDriverState
* coroutine_fn no_co_wrapper
118 bdrv_co_open(const char *filename
, const char *reference
,
119 QDict
*options
, int flags
, Error
**errp
);
121 BlockDriverState
*bdrv_new_open_driver_opts(BlockDriver
*drv
,
122 const char *node_name
,
123 QDict
*options
, int flags
,
125 BlockDriverState
*bdrv_new_open_driver(BlockDriver
*drv
, const char *node_name
,
126 int flags
, Error
**errp
);
127 BlockReopenQueue
*bdrv_reopen_queue(BlockReopenQueue
*bs_queue
,
128 BlockDriverState
*bs
, QDict
*options
,
130 void bdrv_reopen_queue_free(BlockReopenQueue
*bs_queue
);
131 int bdrv_reopen_multiple(BlockReopenQueue
*bs_queue
, Error
**errp
);
132 int bdrv_reopen(BlockDriverState
*bs
, QDict
*opts
, bool keep_old_opts
,
134 int bdrv_reopen_set_read_only(BlockDriverState
*bs
, bool read_only
,
136 BlockDriverState
*bdrv_find_backing_image(BlockDriverState
*bs
,
137 const char *backing_file
);
138 void GRAPH_RDLOCK
bdrv_refresh_filename(BlockDriverState
*bs
);
141 bdrv_refresh_limits(BlockDriverState
*bs
, Transaction
*tran
, Error
**errp
);
143 int bdrv_commit(BlockDriverState
*bs
);
144 int GRAPH_RDLOCK
bdrv_make_empty(BdrvChild
*c
, Error
**errp
);
146 void bdrv_register(BlockDriver
*bdrv
);
147 int bdrv_drop_intermediate(BlockDriverState
*top
, BlockDriverState
*base
,
148 const char *backing_file_str
);
150 BlockDriverState
* GRAPH_RDLOCK
151 bdrv_find_overlay(BlockDriverState
*active
, BlockDriverState
*bs
);
153 BlockDriverState
* GRAPH_RDLOCK
bdrv_find_base(BlockDriverState
*bs
);
156 bdrv_freeze_backing_chain(BlockDriverState
*bs
, BlockDriverState
*base
,
159 bdrv_unfreeze_backing_chain(BlockDriverState
*bs
, BlockDriverState
*base
);
162 * The units of offset and total_work_size may be chosen arbitrarily by the
163 * block driver; total_work_size may change during the course of the amendment
166 typedef void BlockDriverAmendStatusCB(BlockDriverState
*bs
, int64_t offset
,
167 int64_t total_work_size
, void *opaque
);
169 bdrv_amend_options(BlockDriverState
*bs_new
, QemuOpts
*opts
,
170 BlockDriverAmendStatusCB
*status_cb
, void *cb_opaque
,
171 bool force
, Error
**errp
);
173 /* check if a named node can be replaced when doing drive-mirror */
174 BlockDriverState
* GRAPH_RDLOCK
175 check_to_replace_node(BlockDriverState
*parent_bs
, const char *node_name
,
178 int no_coroutine_fn GRAPH_RDLOCK
179 bdrv_activate(BlockDriverState
*bs
, Error
**errp
);
181 int coroutine_fn no_co_wrapper_bdrv_rdlock
182 bdrv_co_activate(BlockDriverState
*bs
, Error
**errp
);
184 void bdrv_activate_all(Error
**errp
);
185 int bdrv_inactivate_all(void);
187 int bdrv_flush_all(void);
188 void bdrv_close_all(void);
189 void bdrv_drain_all_begin(void);
190 void bdrv_drain_all_begin_nopoll(void);
191 void bdrv_drain_all_end(void);
192 void bdrv_drain_all(void);
194 void bdrv_aio_cancel(BlockAIOCB
*acb
);
196 int bdrv_has_zero_init_1(BlockDriverState
*bs
);
197 int coroutine_mixed_fn GRAPH_RDLOCK
bdrv_has_zero_init(BlockDriverState
*bs
);
198 BlockDriverState
*bdrv_find_node(const char *node_name
);
199 BlockDeviceInfoList
*bdrv_named_nodes_list(bool flat
, Error
**errp
);
200 XDbgBlockGraph
* GRAPH_RDLOCK
bdrv_get_xdbg_block_graph(Error
**errp
);
201 BlockDriverState
*bdrv_lookup_bs(const char *device
,
202 const char *node_name
,
205 bdrv_chain_contains(BlockDriverState
*top
, BlockDriverState
*base
);
207 BlockDriverState
*bdrv_next_node(BlockDriverState
*bs
);
208 BlockDriverState
*bdrv_next_all_states(BlockDriverState
*bs
);
210 typedef struct BdrvNextIterator
{
212 BDRV_NEXT_BACKEND_ROOTS
,
213 BDRV_NEXT_MONITOR_OWNED
,
216 BlockDriverState
*bs
;
219 BlockDriverState
* GRAPH_RDLOCK
bdrv_first(BdrvNextIterator
*it
);
220 BlockDriverState
* GRAPH_RDLOCK
bdrv_next(BdrvNextIterator
*it
);
221 void bdrv_next_cleanup(BdrvNextIterator
*it
);
223 BlockDriverState
*bdrv_next_monitor_owned(BlockDriverState
*bs
);
224 void bdrv_iterate_format(void (*it
)(void *opaque
, const char *name
),
225 void *opaque
, bool read_only
);
228 bdrv_get_full_backing_filename(BlockDriverState
*bs
, Error
**errp
);
230 char * GRAPH_RDLOCK
bdrv_dirname(BlockDriverState
*bs
, Error
**errp
);
232 void bdrv_img_create(const char *filename
, const char *fmt
,
233 const char *base_filename
, const char *base_fmt
,
234 char *options
, uint64_t img_size
, int flags
,
235 bool quiet
, Error
**errp
);
237 void bdrv_ref(BlockDriverState
*bs
);
238 void no_coroutine_fn
bdrv_unref(BlockDriverState
*bs
);
239 void coroutine_fn no_co_wrapper
bdrv_co_unref(BlockDriverState
*bs
);
240 void GRAPH_WRLOCK
bdrv_schedule_unref(BlockDriverState
*bs
);
243 bdrv_unref_child(BlockDriverState
*parent
, BdrvChild
*child
);
245 void coroutine_fn no_co_wrapper_bdrv_wrlock
246 bdrv_co_unref_child(BlockDriverState
*parent
, BdrvChild
*child
);
248 BdrvChild
* GRAPH_WRLOCK
249 bdrv_attach_child(BlockDriverState
*parent_bs
,
250 BlockDriverState
*child_bs
,
251 const char *child_name
,
252 const BdrvChildClass
*child_class
,
253 BdrvChildRole child_role
,
257 bdrv_op_is_blocked(BlockDriverState
*bs
, BlockOpType op
, Error
**errp
);
259 void bdrv_op_block(BlockDriverState
*bs
, BlockOpType op
, Error
*reason
);
260 void bdrv_op_unblock(BlockDriverState
*bs
, BlockOpType op
, Error
*reason
);
261 void bdrv_op_block_all(BlockDriverState
*bs
, Error
*reason
);
262 void bdrv_op_unblock_all(BlockDriverState
*bs
, Error
*reason
);
263 bool bdrv_op_blocker_is_empty(BlockDriverState
*bs
);
265 int bdrv_debug_breakpoint(BlockDriverState
*bs
, const char *event
,
267 int bdrv_debug_remove_breakpoint(BlockDriverState
*bs
, const char *tag
);
268 int bdrv_debug_resume(BlockDriverState
*bs
, const char *tag
);
269 bool bdrv_debug_is_suspended(BlockDriverState
*bs
, const char *tag
);
272 * Locks the AioContext of @bs if it's not the current AioContext. This avoids
273 * double locking which could lead to deadlocks: This is a coroutine_fn, so we
274 * know we already own the lock of the current AioContext.
276 * May only be called in the main thread.
278 void coroutine_fn
bdrv_co_lock(BlockDriverState
*bs
);
281 * Unlocks the AioContext of @bs if it's not the current AioContext.
283 void coroutine_fn
bdrv_co_unlock(BlockDriverState
*bs
);
285 bool bdrv_child_change_aio_context(BdrvChild
*c
, AioContext
*ctx
,
286 GHashTable
*visited
, Transaction
*tran
,
288 int bdrv_try_change_aio_context(BlockDriverState
*bs
, AioContext
*ctx
,
289 BdrvChild
*ignore_child
, Error
**errp
);
291 int GRAPH_RDLOCK
bdrv_probe_blocksizes(BlockDriverState
*bs
, BlockSizes
*bsz
);
292 int bdrv_probe_geometry(BlockDriverState
*bs
, HDGeometry
*geo
);
295 bdrv_add_child(BlockDriverState
*parent
, BlockDriverState
*child
, Error
**errp
);
298 bdrv_del_child(BlockDriverState
*parent
, BdrvChild
*child
, Error
**errp
);
302 * bdrv_register_buf/bdrv_unregister_buf:
304 * Register/unregister a buffer for I/O. For example, VFIO drivers are
305 * interested to know the memory areas that would later be used for I/O, so
306 * that they can prepare IOMMU mapping etc., to get better performance.
308 * Buffers must not overlap and they must be unregistered with the same <host,
309 * size> values that they were registered with.
311 * Returns: true on success, false on failure
313 bool bdrv_register_buf(BlockDriverState
*bs
, void *host
, size_t size
,
315 void bdrv_unregister_buf(BlockDriverState
*bs
, void *host
, size_t size
);
317 void bdrv_cancel_in_flight(BlockDriverState
*bs
);
319 #endif /* BLOCK_GLOBAL_STATE_H */