xref: /openbmc/qemu/include/sysemu/block-backend.h (revision dd2bf9eb)
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 BlockBackend *blk_new_open(const char *name, const char *filename,
66                            const char *reference, QDict *options, int flags,
67                            Error **errp);
68 int blk_get_refcnt(BlockBackend *blk);
69 void blk_ref(BlockBackend *blk);
70 void blk_unref(BlockBackend *blk);
71 const char *blk_name(BlockBackend *blk);
72 BlockBackend *blk_by_name(const char *name);
73 BlockBackend *blk_next(BlockBackend *blk);
74 
75 BlockDriverState *blk_bs(BlockBackend *blk);
76 void blk_remove_bs(BlockBackend *blk);
77 void blk_insert_bs(BlockBackend *blk, BlockDriverState *bs);
78 
79 void blk_hide_on_behalf_of_hmp_drive_del(BlockBackend *blk);
80 
81 void blk_iostatus_enable(BlockBackend *blk);
82 bool blk_iostatus_is_enabled(const BlockBackend *blk);
83 BlockDeviceIoStatus blk_iostatus(const BlockBackend *blk);
84 void blk_iostatus_disable(BlockBackend *blk);
85 void blk_iostatus_reset(BlockBackend *blk);
86 void blk_iostatus_set_err(BlockBackend *blk, int error);
87 int blk_attach_dev(BlockBackend *blk, void *dev);
88 void blk_attach_dev_nofail(BlockBackend *blk, void *dev);
89 void blk_detach_dev(BlockBackend *blk, void *dev);
90 void *blk_get_attached_dev(BlockBackend *blk);
91 void blk_set_dev_ops(BlockBackend *blk, const BlockDevOps *ops, void *opaque);
92 int blk_read(BlockBackend *blk, int64_t sector_num, uint8_t *buf,
93              int nb_sectors);
94 int blk_read_unthrottled(BlockBackend *blk, int64_t sector_num, uint8_t *buf,
95                          int nb_sectors);
96 int blk_write(BlockBackend *blk, int64_t sector_num, const uint8_t *buf,
97               int nb_sectors);
98 int blk_write_zeroes(BlockBackend *blk, int64_t sector_num,
99                      int nb_sectors, BdrvRequestFlags flags);
100 BlockAIOCB *blk_aio_write_zeroes(BlockBackend *blk, int64_t sector_num,
101                                  int nb_sectors, BdrvRequestFlags flags,
102                                  BlockCompletionFunc *cb, void *opaque);
103 int blk_pread(BlockBackend *blk, int64_t offset, void *buf, int count);
104 int blk_pwrite(BlockBackend *blk, int64_t offset, const void *buf, int count);
105 int64_t blk_getlength(BlockBackend *blk);
106 void blk_get_geometry(BlockBackend *blk, uint64_t *nb_sectors_ptr);
107 int64_t blk_nb_sectors(BlockBackend *blk);
108 BlockAIOCB *blk_aio_readv(BlockBackend *blk, int64_t sector_num,
109                           QEMUIOVector *iov, int nb_sectors,
110                           BlockCompletionFunc *cb, void *opaque);
111 BlockAIOCB *blk_aio_writev(BlockBackend *blk, int64_t sector_num,
112                            QEMUIOVector *iov, int nb_sectors,
113                            BlockCompletionFunc *cb, void *opaque);
114 BlockAIOCB *blk_aio_flush(BlockBackend *blk,
115                           BlockCompletionFunc *cb, void *opaque);
116 BlockAIOCB *blk_aio_discard(BlockBackend *blk,
117                             int64_t sector_num, int nb_sectors,
118                             BlockCompletionFunc *cb, void *opaque);
119 void blk_aio_cancel(BlockAIOCB *acb);
120 void blk_aio_cancel_async(BlockAIOCB *acb);
121 int blk_aio_multiwrite(BlockBackend *blk, BlockRequest *reqs, int num_reqs);
122 int blk_ioctl(BlockBackend *blk, unsigned long int req, void *buf);
123 BlockAIOCB *blk_aio_ioctl(BlockBackend *blk, unsigned long int req, void *buf,
124                           BlockCompletionFunc *cb, void *opaque);
125 int blk_co_discard(BlockBackend *blk, int64_t sector_num, int nb_sectors);
126 int blk_co_flush(BlockBackend *blk);
127 int blk_flush(BlockBackend *blk);
128 int blk_flush_all(void);
129 void blk_drain(BlockBackend *blk);
130 void blk_drain_all(void);
131 void blk_set_on_error(BlockBackend *blk, BlockdevOnError on_read_error,
132                       BlockdevOnError on_write_error);
133 BlockdevOnError blk_get_on_error(BlockBackend *blk, bool is_read);
134 BlockErrorAction blk_get_error_action(BlockBackend *blk, bool is_read,
135                                       int error);
136 void blk_error_action(BlockBackend *blk, BlockErrorAction action,
137                       bool is_read, int error);
138 int blk_is_read_only(BlockBackend *blk);
139 int blk_is_sg(BlockBackend *blk);
140 int blk_enable_write_cache(BlockBackend *blk);
141 void blk_set_enable_write_cache(BlockBackend *blk, bool wce);
142 void blk_invalidate_cache(BlockBackend *blk, Error **errp);
143 bool blk_is_inserted(BlockBackend *blk);
144 bool blk_is_available(BlockBackend *blk);
145 void blk_lock_medium(BlockBackend *blk, bool locked);
146 void blk_eject(BlockBackend *blk, bool eject_flag);
147 int blk_get_flags(BlockBackend *blk);
148 int blk_get_max_transfer_length(BlockBackend *blk);
149 int blk_get_max_iov(BlockBackend *blk);
150 void blk_set_guest_block_size(BlockBackend *blk, int align);
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_close_notifier(BlockBackend *blk, Notifier *notify);
167 void blk_io_plug(BlockBackend *blk);
168 void blk_io_unplug(BlockBackend *blk);
169 BlockAcctStats *blk_get_stats(BlockBackend *blk);
170 BlockBackendRootState *blk_get_root_state(BlockBackend *blk);
171 void blk_update_root_state(BlockBackend *blk);
172 void blk_apply_root_state(BlockBackend *blk, BlockDriverState *bs);
173 int blk_get_open_flags_from_root_state(BlockBackend *blk);
174 
175 void *blk_aio_get(const AIOCBInfo *aiocb_info, BlockBackend *blk,
176                   BlockCompletionFunc *cb, void *opaque);
177 int coroutine_fn blk_co_write_zeroes(BlockBackend *blk, int64_t sector_num,
178                                      int nb_sectors, BdrvRequestFlags flags);
179 int blk_write_compressed(BlockBackend *blk, int64_t sector_num,
180                          const uint8_t *buf, int nb_sectors);
181 int blk_truncate(BlockBackend *blk, int64_t offset);
182 int blk_discard(BlockBackend *blk, int64_t sector_num, int nb_sectors);
183 int blk_save_vmstate(BlockBackend *blk, const uint8_t *buf,
184                      int64_t pos, int size);
185 int blk_load_vmstate(BlockBackend *blk, uint8_t *buf, int64_t pos, int size);
186 int blk_probe_blocksizes(BlockBackend *blk, BlockSizes *bsz);
187 int blk_probe_geometry(BlockBackend *blk, HDGeometry *geo);
188 BlockAIOCB *blk_abort_aio_request(BlockBackend *blk,
189                                   BlockCompletionFunc *cb,
190                                   void *opaque, int ret);
191 
192 #endif
193