include/sysemu/block-backend.h

   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