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 int bdrv_create(BlockDriver *drv, const char* filename, 59 QemuOpts *opts, Error **errp); 60 int bdrv_create_file(const char *filename, QemuOpts *opts, Error **errp); 61 62 BlockDriverState *bdrv_new(void); 63 int bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top, 64 Error **errp); 65 int bdrv_replace_node(BlockDriverState *from, BlockDriverState *to, 66 Error **errp); 67 int bdrv_replace_child_bs(BdrvChild *child, BlockDriverState *new_bs, 68 Error **errp); 69 BlockDriverState *bdrv_insert_node(BlockDriverState *bs, QDict *node_options, 70 int flags, Error **errp); 71 int bdrv_drop_filter(BlockDriverState *bs, Error **errp); 72 73 BdrvChild *bdrv_open_child(const char *filename, 74 QDict *options, const char *bdref_key, 75 BlockDriverState *parent, 76 const BdrvChildClass *child_class, 77 BdrvChildRole child_role, 78 bool allow_none, Error **errp); 79 int bdrv_open_file_child(const char *filename, 80 QDict *options, const char *bdref_key, 81 BlockDriverState *parent, Error **errp); 82 BlockDriverState *bdrv_open_blockdev_ref(BlockdevRef *ref, Error **errp); 83 int bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd, 84 Error **errp); 85 int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, 86 const char *bdref_key, Error **errp); 87 BlockDriverState *bdrv_open(const char *filename, const char *reference, 88 QDict *options, int flags, Error **errp); 89 BlockDriverState *bdrv_new_open_driver_opts(BlockDriver *drv, 90 const char *node_name, 91 QDict *options, int flags, 92 Error **errp); 93 BlockDriverState *bdrv_new_open_driver(BlockDriver *drv, const char *node_name, 94 int flags, Error **errp); 95 BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue, 96 BlockDriverState *bs, QDict *options, 97 bool keep_old_opts); 98 void bdrv_reopen_queue_free(BlockReopenQueue *bs_queue); 99 int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp); 100 int bdrv_reopen(BlockDriverState *bs, QDict *opts, bool keep_old_opts, 101 Error **errp); 102 int bdrv_reopen_set_read_only(BlockDriverState *bs, bool read_only, 103 Error **errp); 104 BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs, 105 const char *backing_file); 106 void bdrv_refresh_filename(BlockDriverState *bs); 107 void bdrv_refresh_limits(BlockDriverState *bs, Transaction *tran, Error **errp); 108 int bdrv_commit(BlockDriverState *bs); 109 int bdrv_make_empty(BdrvChild *c, Error **errp); 110 int bdrv_change_backing_file(BlockDriverState *bs, const char *backing_file, 111 const char *backing_fmt, bool warn); 112 void bdrv_register(BlockDriver *bdrv); 113 int bdrv_drop_intermediate(BlockDriverState *top, BlockDriverState *base, 114 const char *backing_file_str); 115 BlockDriverState *bdrv_find_overlay(BlockDriverState *active, 116 BlockDriverState *bs); 117 BlockDriverState *bdrv_find_base(BlockDriverState *bs); 118 bool bdrv_is_backing_chain_frozen(BlockDriverState *bs, BlockDriverState *base, 119 Error **errp); 120 int bdrv_freeze_backing_chain(BlockDriverState *bs, BlockDriverState *base, 121 Error **errp); 122 void bdrv_unfreeze_backing_chain(BlockDriverState *bs, BlockDriverState *base); 123 124 /* 125 * The units of offset and total_work_size may be chosen arbitrarily by the 126 * block driver; total_work_size may change during the course of the amendment 127 * operation 128 */ 129 typedef void BlockDriverAmendStatusCB(BlockDriverState *bs, int64_t offset, 130 int64_t total_work_size, void *opaque); 131 int bdrv_amend_options(BlockDriverState *bs_new, QemuOpts *opts, 132 BlockDriverAmendStatusCB *status_cb, void *cb_opaque, 133 bool force, 134 Error **errp); 135 136 /* check if a named node can be replaced when doing drive-mirror */ 137 BlockDriverState *check_to_replace_node(BlockDriverState *parent_bs, 138 const char *node_name, Error **errp); 139 140 int bdrv_activate(BlockDriverState *bs, Error **errp); 141 void bdrv_activate_all(Error **errp); 142 int bdrv_inactivate_all(void); 143 144 int bdrv_flush_all(void); 145 void bdrv_close_all(void); 146 void bdrv_drain_all_begin(void); 147 void bdrv_drain_all_end(void); 148 void bdrv_drain_all(void); 149 150 int bdrv_has_zero_init_1(BlockDriverState *bs); 151 int bdrv_has_zero_init(BlockDriverState *bs); 152 BlockDriverState *bdrv_find_node(const char *node_name); 153 BlockDeviceInfoList *bdrv_named_nodes_list(bool flat, Error **errp); 154 XDbgBlockGraph *bdrv_get_xdbg_block_graph(Error **errp); 155 BlockDriverState *bdrv_lookup_bs(const char *device, 156 const char *node_name, 157 Error **errp); 158 bool bdrv_chain_contains(BlockDriverState *top, BlockDriverState *base); 159 BlockDriverState *bdrv_next_node(BlockDriverState *bs); 160 BlockDriverState *bdrv_next_all_states(BlockDriverState *bs); 161 162 typedef struct BdrvNextIterator { 163 enum { 164 BDRV_NEXT_BACKEND_ROOTS, 165 BDRV_NEXT_MONITOR_OWNED, 166 } phase; 167 BlockBackend *blk; 168 BlockDriverState *bs; 169 } BdrvNextIterator; 170 171 BlockDriverState *bdrv_first(BdrvNextIterator *it); 172 BlockDriverState *bdrv_next(BdrvNextIterator *it); 173 void bdrv_next_cleanup(BdrvNextIterator *it); 174 175 BlockDriverState *bdrv_next_monitor_owned(BlockDriverState *bs); 176 void bdrv_iterate_format(void (*it)(void *opaque, const char *name), 177 void *opaque, bool read_only); 178 char *bdrv_get_full_backing_filename(BlockDriverState *bs, Error **errp); 179 char *bdrv_dirname(BlockDriverState *bs, Error **errp); 180 181 void bdrv_img_create(const char *filename, const char *fmt, 182 const char *base_filename, const char *base_fmt, 183 char *options, uint64_t img_size, int flags, 184 bool quiet, Error **errp); 185 186 void bdrv_ref(BlockDriverState *bs); 187 void bdrv_unref(BlockDriverState *bs); 188 void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child); 189 BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, 190 BlockDriverState *child_bs, 191 const char *child_name, 192 const BdrvChildClass *child_class, 193 BdrvChildRole child_role, 194 Error **errp); 195 196 bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp); 197 void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason); 198 void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason); 199 void bdrv_op_block_all(BlockDriverState *bs, Error *reason); 200 void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason); 201 bool bdrv_op_blocker_is_empty(BlockDriverState *bs); 202 203 int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event, 204 const char *tag); 205 int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag); 206 int bdrv_debug_resume(BlockDriverState *bs, const char *tag); 207 bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag); 208 209 /** 210 * Locks the AioContext of @bs if it's not the current AioContext. This avoids 211 * double locking which could lead to deadlocks: This is a coroutine_fn, so we 212 * know we already own the lock of the current AioContext. 213 * 214 * May only be called in the main thread. 215 */ 216 void coroutine_fn bdrv_co_lock(BlockDriverState *bs); 217 218 /** 219 * Unlocks the AioContext of @bs if it's not the current AioContext. 220 */ 221 void coroutine_fn bdrv_co_unlock(BlockDriverState *bs); 222 223 bool bdrv_child_change_aio_context(BdrvChild *c, AioContext *ctx, 224 GHashTable *visited, Transaction *tran, 225 Error **errp); 226 int bdrv_try_change_aio_context(BlockDriverState *bs, AioContext *ctx, 227 BdrvChild *ignore_child, Error **errp); 228 229 int bdrv_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz); 230 int bdrv_probe_geometry(BlockDriverState *bs, HDGeometry *geo); 231 232 void bdrv_add_child(BlockDriverState *parent, BlockDriverState *child, 233 Error **errp); 234 void bdrv_del_child(BlockDriverState *parent, BdrvChild *child, Error **errp); 235 236 /** 237 * 238 * bdrv_register_buf/bdrv_unregister_buf: 239 * 240 * Register/unregister a buffer for I/O. For example, VFIO drivers are 241 * interested to know the memory areas that would later be used for I/O, so 242 * that they can prepare IOMMU mapping etc., to get better performance. 243 * 244 * Buffers must not overlap and they must be unregistered with the same <host, 245 * size> values that they were registered with. 246 * 247 * Returns: true on success, false on failure 248 */ 249 bool bdrv_register_buf(BlockDriverState *bs, void *host, size_t size, 250 Error **errp); 251 void bdrv_unregister_buf(BlockDriverState *bs, void *host, size_t size); 252 253 void bdrv_cancel_in_flight(BlockDriverState *bs); 254 255 #endif /* BLOCK_GLOBAL_STATE_H */ 256