1 /* 2 * QEMU Block backends 3 * 4 * Copyright (C) 2014 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/typedefs.h" 17 #include "qapi/error.h" 18 19 /* 20 * TODO Have to include block/block.h for a bunch of block layer 21 * types. Unfortunately, this pulls in the whole BlockDriverState 22 * API, which we don't want used by many BlockBackend users. Some of 23 * the types belong here, and the rest should be split into a common 24 * header and one for the BlockDriverState API. 25 */ 26 #include "block/block.h" 27 28 /* Callbacks for block device models */ 29 typedef struct BlockDevOps { 30 /* 31 * Runs when virtual media changed (monitor commands eject, change) 32 * Argument load is true on load and false on eject. 33 * Beware: doesn't run when a host device's physical media 34 * changes. Sure would be useful if it did. 35 * Device models with removable media must implement this callback. 36 */ 37 void (*change_media_cb)(void *opaque, bool load); 38 /* 39 * Runs when an eject request is issued from the monitor, the tray 40 * is closed, and the medium is locked. 41 * Device models that do not implement is_medium_locked will not need 42 * this callback. Device models that can lock the medium or tray might 43 * want to implement the callback and unlock the tray when "force" is 44 * true, even if they do not support eject requests. 45 */ 46 void (*eject_request_cb)(void *opaque, bool force); 47 /* 48 * Is the virtual tray open? 49 * Device models implement this only when the device has a tray. 50 */ 51 bool (*is_tray_open)(void *opaque); 52 /* 53 * Is the virtual medium locked into the device? 54 * Device models implement this only when device has such a lock. 55 */ 56 bool (*is_medium_locked)(void *opaque); 57 /* 58 * Runs when the size changed (e.g. monitor command block_resize) 59 */ 60 void (*resize_cb)(void *opaque); 61 } BlockDevOps; 62 63 BlockBackend *blk_new(const char *name, Error **errp); 64 BlockBackend *blk_new_with_bs(const char *name, Error **errp); 65 void blk_ref(BlockBackend *blk); 66 void blk_unref(BlockBackend *blk); 67 const char *blk_name(BlockBackend *blk); 68 BlockBackend *blk_by_name(const char *name); 69 BlockBackend *blk_next(BlockBackend *blk); 70 71 BlockDriverState *blk_bs(BlockBackend *blk); 72 73 void blk_hide_on_behalf_of_do_drive_del(BlockBackend *blk); 74 75 void blk_iostatus_enable(BlockBackend *blk); 76 int blk_attach_dev(BlockBackend *blk, void *dev); 77 void blk_attach_dev_nofail(BlockBackend *blk, void *dev); 78 void blk_detach_dev(BlockBackend *blk, void *dev); 79 void *blk_get_attached_dev(BlockBackend *blk); 80 void blk_set_dev_ops(BlockBackend *blk, const BlockDevOps *ops, void *opaque); 81 int blk_read(BlockBackend *blk, int64_t sector_num, uint8_t *buf, 82 int nb_sectors); 83 int blk_read_unthrottled(BlockBackend *blk, int64_t sector_num, uint8_t *buf, 84 int nb_sectors); 85 int blk_write(BlockBackend *blk, int64_t sector_num, const uint8_t *buf, 86 int nb_sectors); 87 BlockAIOCB *blk_aio_write_zeroes(BlockBackend *blk, int64_t sector_num, 88 int nb_sectors, BdrvRequestFlags flags, 89 BlockCompletionFunc *cb, void *opaque); 90 int blk_pread(BlockBackend *blk, int64_t offset, void *buf, int count); 91 int blk_pwrite(BlockBackend *blk, int64_t offset, const void *buf, int count); 92 int64_t blk_getlength(BlockBackend *blk); 93 void blk_get_geometry(BlockBackend *blk, uint64_t *nb_sectors_ptr); 94 BlockAIOCB *blk_aio_readv(BlockBackend *blk, int64_t sector_num, 95 QEMUIOVector *iov, int nb_sectors, 96 BlockCompletionFunc *cb, void *opaque); 97 BlockAIOCB *blk_aio_writev(BlockBackend *blk, int64_t sector_num, 98 QEMUIOVector *iov, int nb_sectors, 99 BlockCompletionFunc *cb, void *opaque); 100 BlockAIOCB *blk_aio_flush(BlockBackend *blk, 101 BlockCompletionFunc *cb, void *opaque); 102 BlockAIOCB *blk_aio_discard(BlockBackend *blk, 103 int64_t sector_num, int nb_sectors, 104 BlockCompletionFunc *cb, void *opaque); 105 void blk_aio_cancel(BlockAIOCB *acb); 106 void blk_aio_cancel_async(BlockAIOCB *acb); 107 int blk_aio_multiwrite(BlockBackend *blk, BlockRequest *reqs, int num_reqs); 108 int blk_ioctl(BlockBackend *blk, unsigned long int req, void *buf); 109 BlockAIOCB *blk_aio_ioctl(BlockBackend *blk, unsigned long int req, void *buf, 110 BlockCompletionFunc *cb, void *opaque); 111 int blk_flush(BlockBackend *blk); 112 int blk_flush_all(void); 113 void blk_drain_all(void); 114 BlockdevOnError blk_get_on_error(BlockBackend *blk, bool is_read); 115 BlockErrorAction blk_get_error_action(BlockBackend *blk, bool is_read, 116 int error); 117 void blk_error_action(BlockBackend *blk, BlockErrorAction action, 118 bool is_read, int error); 119 int blk_is_read_only(BlockBackend *blk); 120 int blk_is_sg(BlockBackend *blk); 121 int blk_enable_write_cache(BlockBackend *blk); 122 void blk_set_enable_write_cache(BlockBackend *blk, bool wce); 123 int blk_is_inserted(BlockBackend *blk); 124 void blk_lock_medium(BlockBackend *blk, bool locked); 125 void blk_eject(BlockBackend *blk, bool eject_flag); 126 int blk_get_flags(BlockBackend *blk); 127 void blk_set_guest_block_size(BlockBackend *blk, int align); 128 void *blk_blockalign(BlockBackend *blk, size_t size); 129 bool blk_op_is_blocked(BlockBackend *blk, BlockOpType op, Error **errp); 130 void blk_op_unblock(BlockBackend *blk, BlockOpType op, Error *reason); 131 void blk_op_block_all(BlockBackend *blk, Error *reason); 132 void blk_op_unblock_all(BlockBackend *blk, Error *reason); 133 AioContext *blk_get_aio_context(BlockBackend *blk); 134 void blk_set_aio_context(BlockBackend *blk, AioContext *new_context); 135 void blk_io_plug(BlockBackend *blk); 136 void blk_io_unplug(BlockBackend *blk); 137 BlockAcctStats *blk_get_stats(BlockBackend *blk); 138 139 void *blk_aio_get(const AIOCBInfo *aiocb_info, BlockBackend *blk, 140 BlockCompletionFunc *cb, void *opaque); 141 142 #endif 143