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 BlockBackend *blk_new(Error **errp); 63 BlockBackend *blk_new_with_bs(Error **errp); 64 BlockBackend *blk_new_open(const char *filename, const char *reference, 65 QDict *options, int flags, Error **errp); 66 int blk_get_refcnt(BlockBackend *blk); 67 void blk_ref(BlockBackend *blk); 68 void blk_unref(BlockBackend *blk); 69 void blk_remove_all_bs(void); 70 const char *blk_name(BlockBackend *blk); 71 BlockBackend *blk_by_name(const char *name); 72 BlockBackend *blk_next(BlockBackend *blk); 73 BlockDriverState *blk_next_root_bs(BlockDriverState *bs); 74 bool monitor_add_blk(BlockBackend *blk, const char *name, Error **errp); 75 void monitor_remove_blk(BlockBackend *blk); 76 77 BlockDriverState *blk_bs(BlockBackend *blk); 78 void blk_remove_bs(BlockBackend *blk); 79 void blk_insert_bs(BlockBackend *blk, BlockDriverState *bs); 80 81 void blk_set_allow_write_beyond_eof(BlockBackend *blk, bool allow); 82 void blk_iostatus_enable(BlockBackend *blk); 83 bool blk_iostatus_is_enabled(const BlockBackend *blk); 84 BlockDeviceIoStatus blk_iostatus(const BlockBackend *blk); 85 void blk_iostatus_disable(BlockBackend *blk); 86 void blk_iostatus_reset(BlockBackend *blk); 87 void blk_iostatus_set_err(BlockBackend *blk, int error); 88 int blk_attach_dev(BlockBackend *blk, void *dev); 89 void blk_attach_dev_nofail(BlockBackend *blk, void *dev); 90 void blk_detach_dev(BlockBackend *blk, void *dev); 91 void *blk_get_attached_dev(BlockBackend *blk); 92 void blk_set_dev_ops(BlockBackend *blk, const BlockDevOps *ops, void *opaque); 93 int blk_pread_unthrottled(BlockBackend *blk, int64_t offset, uint8_t *buf, 94 int count); 95 int blk_write_zeroes(BlockBackend *blk, int64_t offset, 96 int count, BdrvRequestFlags flags); 97 BlockAIOCB *blk_aio_write_zeroes(BlockBackend *blk, int64_t offset, 98 int count, BdrvRequestFlags flags, 99 BlockCompletionFunc *cb, void *opaque); 100 int blk_pread(BlockBackend *blk, int64_t offset, void *buf, int count); 101 int blk_pwrite(BlockBackend *blk, int64_t offset, const void *buf, int count, 102 BdrvRequestFlags flags); 103 int64_t blk_getlength(BlockBackend *blk); 104 void blk_get_geometry(BlockBackend *blk, uint64_t *nb_sectors_ptr); 105 int64_t blk_nb_sectors(BlockBackend *blk); 106 BlockAIOCB *blk_aio_preadv(BlockBackend *blk, int64_t offset, 107 QEMUIOVector *qiov, BdrvRequestFlags flags, 108 BlockCompletionFunc *cb, void *opaque); 109 BlockAIOCB *blk_aio_pwritev(BlockBackend *blk, int64_t offset, 110 QEMUIOVector *qiov, BdrvRequestFlags flags, 111 BlockCompletionFunc *cb, void *opaque); 112 BlockAIOCB *blk_aio_flush(BlockBackend *blk, 113 BlockCompletionFunc *cb, void *opaque); 114 BlockAIOCB *blk_aio_discard(BlockBackend *blk, 115 int64_t sector_num, int nb_sectors, 116 BlockCompletionFunc *cb, void *opaque); 117 void blk_aio_cancel(BlockAIOCB *acb); 118 void blk_aio_cancel_async(BlockAIOCB *acb); 119 int blk_aio_multiwrite(BlockBackend *blk, BlockRequest *reqs, int num_reqs); 120 int blk_ioctl(BlockBackend *blk, unsigned long int req, void *buf); 121 BlockAIOCB *blk_aio_ioctl(BlockBackend *blk, unsigned long int req, void *buf, 122 BlockCompletionFunc *cb, void *opaque); 123 int blk_co_discard(BlockBackend *blk, int64_t sector_num, int nb_sectors); 124 int blk_co_flush(BlockBackend *blk); 125 int blk_flush(BlockBackend *blk); 126 int blk_flush_all(void); 127 int blk_commit_all(void); 128 void blk_drain(BlockBackend *blk); 129 void blk_drain_all(void); 130 void blk_set_on_error(BlockBackend *blk, BlockdevOnError on_read_error, 131 BlockdevOnError on_write_error); 132 BlockdevOnError blk_get_on_error(BlockBackend *blk, bool is_read); 133 BlockErrorAction blk_get_error_action(BlockBackend *blk, bool is_read, 134 int error); 135 void blk_error_action(BlockBackend *blk, BlockErrorAction action, 136 bool is_read, int error); 137 int blk_is_read_only(BlockBackend *blk); 138 int blk_is_sg(BlockBackend *blk); 139 int blk_enable_write_cache(BlockBackend *blk); 140 void blk_set_enable_write_cache(BlockBackend *blk, bool wce); 141 void blk_invalidate_cache(BlockBackend *blk, Error **errp); 142 bool blk_is_inserted(BlockBackend *blk); 143 bool blk_is_available(BlockBackend *blk); 144 void blk_lock_medium(BlockBackend *blk, bool locked); 145 void blk_eject(BlockBackend *blk, bool eject_flag); 146 int blk_get_flags(BlockBackend *blk); 147 int blk_get_max_transfer_length(BlockBackend *blk); 148 int blk_get_max_iov(BlockBackend *blk); 149 void blk_set_guest_block_size(BlockBackend *blk, int align); 150 void *blk_try_blockalign(BlockBackend *blk, size_t size); 151 void *blk_blockalign(BlockBackend *blk, size_t size); 152 bool blk_op_is_blocked(BlockBackend *blk, BlockOpType op, Error **errp); 153 void blk_op_unblock(BlockBackend *blk, BlockOpType op, Error *reason); 154 void blk_op_block_all(BlockBackend *blk, Error *reason); 155 void blk_op_unblock_all(BlockBackend *blk, Error *reason); 156 AioContext *blk_get_aio_context(BlockBackend *blk); 157 void blk_set_aio_context(BlockBackend *blk, AioContext *new_context); 158 void blk_add_aio_context_notifier(BlockBackend *blk, 159 void (*attached_aio_context)(AioContext *new_context, void *opaque), 160 void (*detach_aio_context)(void *opaque), void *opaque); 161 void blk_remove_aio_context_notifier(BlockBackend *blk, 162 void (*attached_aio_context)(AioContext *, 163 void *), 164 void (*detach_aio_context)(void *), 165 void *opaque); 166 void blk_add_remove_bs_notifier(BlockBackend *blk, Notifier *notify); 167 void blk_add_insert_bs_notifier(BlockBackend *blk, Notifier *notify); 168 void blk_io_plug(BlockBackend *blk); 169 void blk_io_unplug(BlockBackend *blk); 170 BlockAcctStats *blk_get_stats(BlockBackend *blk); 171 BlockBackendRootState *blk_get_root_state(BlockBackend *blk); 172 void blk_update_root_state(BlockBackend *blk); 173 void blk_apply_root_state(BlockBackend *blk, BlockDriverState *bs); 174 int blk_get_open_flags_from_root_state(BlockBackend *blk); 175 176 void *blk_aio_get(const AIOCBInfo *aiocb_info, BlockBackend *blk, 177 BlockCompletionFunc *cb, void *opaque); 178 int coroutine_fn blk_co_write_zeroes(BlockBackend *blk, int64_t offset, 179 int count, BdrvRequestFlags flags); 180 int blk_write_compressed(BlockBackend *blk, int64_t sector_num, 181 const uint8_t *buf, int nb_sectors); 182 int blk_truncate(BlockBackend *blk, int64_t offset); 183 int blk_discard(BlockBackend *blk, int64_t sector_num, int nb_sectors); 184 int blk_save_vmstate(BlockBackend *blk, const uint8_t *buf, 185 int64_t pos, int size); 186 int blk_load_vmstate(BlockBackend *blk, uint8_t *buf, int64_t pos, int size); 187 int blk_probe_blocksizes(BlockBackend *blk, BlockSizes *bsz); 188 int blk_probe_geometry(BlockBackend *blk, HDGeometry *geo); 189 BlockAIOCB *blk_abort_aio_request(BlockBackend *blk, 190 BlockCompletionFunc *cb, 191 void *opaque, int ret); 192 193 #endif 194