1 /* 2 * QEMU System Emulator block driver 3 * 4 * Copyright (c) 2003 Fabrice Bellard 5 * 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: 12 * 13 * The above copyright notice and this permission notice shall be included in 14 * all copies or substantial portions of the Software. 15 * 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 22 * THE SOFTWARE. 23 */ 24 #ifndef BLOCK_GLOBAL_STATE_H 25 #define BLOCK_GLOBAL_STATE_H 26 27 #include "block-common.h" 28 29 /* 30 * Global state (GS) API. These functions run under the BQL. 31 * 32 * If a function modifies the graph, it also uses drain and/or 33 * aio_context_acquire/release to be sure it has unique access. 34 * aio_context locking is needed together with BQL because of 35 * the thread-safe I/O API that concurrently runs and accesses 36 * the graph without the BQL. 37 * 38 * It is important to note that not all of these functions are 39 * necessarily limited to running under the BQL, but they would 40 * require additional auditing and many small thread-safety changes 41 * to move them into the I/O API. Often it's not worth doing that 42 * work since the APIs are only used with the BQL held at the 43 * moment, so they have been placed in the GS API (for now). 44 * 45 * These functions can call any function from this and other categories 46 * (I/O, "I/O or GS", Common), but must be invoked only by other GS APIs. 47 * 48 * All functions in this header must use the macro 49 * GLOBAL_STATE_CODE(); 50 * to catch when they are accidentally called without the BQL. 51 */ 52 53 void bdrv_init(void); 54 BlockDriver *bdrv_find_protocol(const char *filename, 55 bool allow_protocol_prefix, 56 Error **errp); 57 BlockDriver *bdrv_find_format(const char *format_name); 58 59 int coroutine_fn bdrv_co_create(BlockDriver *drv, const char *filename, 60 QemuOpts *opts, Error **errp); 61 int co_wrapper bdrv_create(BlockDriver *drv, const char *filename, 62 QemuOpts *opts, Error **errp); 63 64 int coroutine_fn bdrv_co_create_file(const char *filename, QemuOpts *opts, 65 Error **errp); 66 67 BlockDriverState *bdrv_new(void); 68 int bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top, 69 Error **errp); 70 int bdrv_replace_node(BlockDriverState *from, BlockDriverState *to, 71 Error **errp); 72 int bdrv_replace_child_bs(BdrvChild *child, BlockDriverState *new_bs, 73 Error **errp); 74 BlockDriverState *bdrv_insert_node(BlockDriverState *bs, QDict *node_options, 75 int flags, Error **errp); 76 int bdrv_drop_filter(BlockDriverState *bs, Error **errp); 77 78 BdrvChild *bdrv_open_child(const char *filename, 79 QDict *options, const char *bdref_key, 80 BlockDriverState *parent, 81 const BdrvChildClass *child_class, 82 BdrvChildRole child_role, 83 bool allow_none, Error **errp); 84 int bdrv_open_file_child(const char *filename, 85 QDict *options, const char *bdref_key, 86 BlockDriverState *parent, Error **errp); 87 BlockDriverState *bdrv_open_blockdev_ref(BlockdevRef *ref, Error **errp); 88 int bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd, 89 Error **errp); 90 int bdrv_set_backing_hd_drained(BlockDriverState *bs, 91 BlockDriverState *backing_hd, 92 Error **errp); 93 int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, 94 const char *bdref_key, Error **errp); 95 BlockDriverState *bdrv_open(const char *filename, const char *reference, 96 QDict *options, int flags, Error **errp); 97 BlockDriverState *bdrv_new_open_driver_opts(BlockDriver *drv, 98 const char *node_name, 99 QDict *options, int flags, 100 Error **errp); 101 BlockDriverState *bdrv_new_open_driver(BlockDriver *drv, const char *node_name, 102 int flags, Error **errp); 103 BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue, 104 BlockDriverState *bs, QDict *options, 105 bool keep_old_opts); 106 void bdrv_reopen_queue_free(BlockReopenQueue *bs_queue); 107 int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp); 108 int bdrv_reopen(BlockDriverState *bs, QDict *opts, bool keep_old_opts, 109 Error **errp); 110 int bdrv_reopen_set_read_only(BlockDriverState *bs, bool read_only, 111 Error **errp); 112 BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs, 113 const char *backing_file); 114 void bdrv_refresh_filename(BlockDriverState *bs); 115 void bdrv_refresh_limits(BlockDriverState *bs, Transaction *tran, Error **errp); 116 int bdrv_commit(BlockDriverState *bs); 117 int bdrv_make_empty(BdrvChild *c, Error **errp); 118 int bdrv_change_backing_file(BlockDriverState *bs, const char *backing_file, 119 const char *backing_fmt, bool warn); 120 void bdrv_register(BlockDriver *bdrv); 121 int bdrv_drop_intermediate(BlockDriverState *top, BlockDriverState *base, 122 const char *backing_file_str); 123 BlockDriverState *bdrv_find_overlay(BlockDriverState *active, 124 BlockDriverState *bs); 125 BlockDriverState *bdrv_find_base(BlockDriverState *bs); 126 bool bdrv_is_backing_chain_frozen(BlockDriverState *bs, BlockDriverState *base, 127 Error **errp); 128 int bdrv_freeze_backing_chain(BlockDriverState *bs, BlockDriverState *base, 129 Error **errp); 130 void bdrv_unfreeze_backing_chain(BlockDriverState *bs, BlockDriverState *base); 131 132 /* 133 * The units of offset and total_work_size may be chosen arbitrarily by the 134 * block driver; total_work_size may change during the course of the amendment 135 * operation 136 */ 137 typedef void BlockDriverAmendStatusCB(BlockDriverState *bs, int64_t offset, 138 int64_t total_work_size, void *opaque); 139 int bdrv_amend_options(BlockDriverState *bs_new, QemuOpts *opts, 140 BlockDriverAmendStatusCB *status_cb, void *cb_opaque, 141 bool force, 142 Error **errp); 143 144 /* check if a named node can be replaced when doing drive-mirror */ 145 BlockDriverState *check_to_replace_node(BlockDriverState *parent_bs, 146 const char *node_name, Error **errp); 147 148 int bdrv_activate(BlockDriverState *bs, Error **errp); 149 void bdrv_activate_all(Error **errp); 150 int bdrv_inactivate_all(void); 151 152 int bdrv_flush_all(void); 153 void bdrv_close_all(void); 154 void bdrv_drain_all_begin(void); 155 void bdrv_drain_all_begin_nopoll(void); 156 void bdrv_drain_all_end(void); 157 void bdrv_drain_all(void); 158 159 int bdrv_has_zero_init_1(BlockDriverState *bs); 160 int bdrv_has_zero_init(BlockDriverState *bs); 161 BlockDriverState *bdrv_find_node(const char *node_name); 162 BlockDeviceInfoList *bdrv_named_nodes_list(bool flat, Error **errp); 163 XDbgBlockGraph *bdrv_get_xdbg_block_graph(Error **errp); 164 BlockDriverState *bdrv_lookup_bs(const char *device, 165 const char *node_name, 166 Error **errp); 167 bool bdrv_chain_contains(BlockDriverState *top, BlockDriverState *base); 168 BlockDriverState *bdrv_next_node(BlockDriverState *bs); 169 BlockDriverState *bdrv_next_all_states(BlockDriverState *bs); 170 171 typedef struct BdrvNextIterator { 172 enum { 173 BDRV_NEXT_BACKEND_ROOTS, 174 BDRV_NEXT_MONITOR_OWNED, 175 } phase; 176 BlockBackend *blk; 177 BlockDriverState *bs; 178 } BdrvNextIterator; 179 180 BlockDriverState *bdrv_first(BdrvNextIterator *it); 181 BlockDriverState *bdrv_next(BdrvNextIterator *it); 182 void bdrv_next_cleanup(BdrvNextIterator *it); 183 184 BlockDriverState *bdrv_next_monitor_owned(BlockDriverState *bs); 185 void bdrv_iterate_format(void (*it)(void *opaque, const char *name), 186 void *opaque, bool read_only); 187 char *bdrv_get_full_backing_filename(BlockDriverState *bs, Error **errp); 188 char *bdrv_dirname(BlockDriverState *bs, Error **errp); 189 190 void bdrv_img_create(const char *filename, const char *fmt, 191 const char *base_filename, const char *base_fmt, 192 char *options, uint64_t img_size, int flags, 193 bool quiet, Error **errp); 194 195 void bdrv_ref(BlockDriverState *bs); 196 void bdrv_unref(BlockDriverState *bs); 197 void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child); 198 BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, 199 BlockDriverState *child_bs, 200 const char *child_name, 201 const BdrvChildClass *child_class, 202 BdrvChildRole child_role, 203 Error **errp); 204 205 bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp); 206 void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason); 207 void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason); 208 void bdrv_op_block_all(BlockDriverState *bs, Error *reason); 209 void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason); 210 bool bdrv_op_blocker_is_empty(BlockDriverState *bs); 211 212 int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event, 213 const char *tag); 214 int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag); 215 int bdrv_debug_resume(BlockDriverState *bs, const char *tag); 216 bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag); 217 218 /** 219 * Locks the AioContext of @bs if it's not the current AioContext. This avoids 220 * double locking which could lead to deadlocks: This is a coroutine_fn, so we 221 * know we already own the lock of the current AioContext. 222 * 223 * May only be called in the main thread. 224 */ 225 void coroutine_fn bdrv_co_lock(BlockDriverState *bs); 226 227 /** 228 * Unlocks the AioContext of @bs if it's not the current AioContext. 229 */ 230 void coroutine_fn bdrv_co_unlock(BlockDriverState *bs); 231 232 bool bdrv_child_change_aio_context(BdrvChild *c, AioContext *ctx, 233 GHashTable *visited, Transaction *tran, 234 Error **errp); 235 int bdrv_try_change_aio_context(BlockDriverState *bs, AioContext *ctx, 236 BdrvChild *ignore_child, Error **errp); 237 238 int bdrv_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz); 239 int bdrv_probe_geometry(BlockDriverState *bs, HDGeometry *geo); 240 241 void bdrv_add_child(BlockDriverState *parent, BlockDriverState *child, 242 Error **errp); 243 void bdrv_del_child(BlockDriverState *parent, BdrvChild *child, Error **errp); 244 245 /** 246 * 247 * bdrv_register_buf/bdrv_unregister_buf: 248 * 249 * Register/unregister a buffer for I/O. For example, VFIO drivers are 250 * interested to know the memory areas that would later be used for I/O, so 251 * that they can prepare IOMMU mapping etc., to get better performance. 252 * 253 * Buffers must not overlap and they must be unregistered with the same <host, 254 * size> values that they were registered with. 255 * 256 * Returns: true on success, false on failure 257 */ 258 bool bdrv_register_buf(BlockDriverState *bs, void *host, size_t size, 259 Error **errp); 260 void bdrv_unregister_buf(BlockDriverState *bs, void *host, size_t size); 261 262 void bdrv_cancel_in_flight(BlockDriverState *bs); 263 264 #endif /* BLOCK_GLOBAL_STATE_H */ 265