/* * QEMU System Emulator block driver * * Copyright (c) 2003 Fabrice Bellard * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ #ifndef BLOCK_INT_H #define BLOCK_INT_H #include "block.h" #include "qemu-option.h" #include "qemu-queue.h" #include "qemu-coroutine.h" #include "qemu-timer.h" #include "qapi-types.h" #define BLOCK_FLAG_ENCRYPT 1 #define BLOCK_FLAG_COMPAT6 4 #define BLOCK_IO_LIMIT_READ 0 #define BLOCK_IO_LIMIT_WRITE 1 #define BLOCK_IO_LIMIT_TOTAL 2 #define BLOCK_IO_SLICE_TIME 100000000 #define NANOSECONDS_PER_SECOND 1000000000.0 #define BLOCK_OPT_SIZE "size" #define BLOCK_OPT_ENCRYPT "encryption" #define BLOCK_OPT_COMPAT6 "compat6" #define BLOCK_OPT_BACKING_FILE "backing_file" #define BLOCK_OPT_BACKING_FMT "backing_fmt" #define BLOCK_OPT_CLUSTER_SIZE "cluster_size" #define BLOCK_OPT_TABLE_SIZE "table_size" #define BLOCK_OPT_PREALLOC "preallocation" #define BLOCK_OPT_SUBFMT "subformat" #define BLOCK_OPT_COMPAT_LEVEL "compat" typedef struct BdrvTrackedRequest BdrvTrackedRequest; typedef struct BlockIOLimit { int64_t bps[3]; int64_t iops[3]; } BlockIOLimit; typedef struct BlockIOBaseValue { uint64_t bytes[2]; uint64_t ios[2]; } BlockIOBaseValue; typedef struct BlockJob BlockJob; /** * BlockJobType: * * A class type for block job objects. */ typedef struct BlockJobType { /** Derived BlockJob struct size */ size_t instance_size; /** String describing the operation, part of query-block-jobs QMP API */ const char *job_type; /** Optional callback for job types that support setting a speed limit */ void (*set_speed)(BlockJob *job, int64_t speed, Error **errp); } BlockJobType; /** * BlockJob: * * Long-running operation on a BlockDriverState. */ struct BlockJob { /** The job type, including the job vtable. */ const BlockJobType *job_type; /** The block device on which the job is operating. */ BlockDriverState *bs; /** * The coroutine that executes the job. If not NULL, it is * reentered when busy is false and the job is cancelled. */ Coroutine *co; /** * Set to true if the job should cancel itself. The flag must * always be tested just before toggling the busy flag from false * to true. After a job has been cancelled, it should only yield * if #qemu_aio_wait will ("sooner or later") reenter the coroutine. */ bool cancelled; /** * Set to false by the job while it is in a quiescent state, where * no I/O is pending and the job has yielded on any condition * that is not detected by #qemu_aio_wait, such as a timer. */ bool busy; /** Offset that is published by the query-block-jobs QMP API */ int64_t offset; /** Length that is published by the query-block-jobs QMP API */ int64_t len; /** Speed that was set with @block_job_set_speed. */ int64_t speed; /** The completion function that will be called when the job completes. */ BlockDriverCompletionFunc *cb; /** The opaque value that is passed to the completion function. */ void *opaque; }; struct BlockDriver { const char *format_name; int instance_size; int (*bdrv_probe)(const uint8_t *buf, int buf_size, const char *filename); int (*bdrv_probe_device)(const char *filename); int (*bdrv_open)(BlockDriverState *bs, int flags); int (*bdrv_file_open)(BlockDriverState *bs, const char *filename, int flags); int (*bdrv_read)(BlockDriverState *bs, int64_t sector_num, uint8_t *buf, int nb_sectors); int (*bdrv_write)(BlockDriverState *bs, int64_t sector_num, const uint8_t *buf, int nb_sectors); void (*bdrv_close)(BlockDriverState *bs); void (*bdrv_rebind)(BlockDriverState *bs); int (*bdrv_create)(const char *filename, QEMUOptionParameter *options); int (*bdrv_set_key)(BlockDriverState *bs, const char *key); int (*bdrv_make_empty)(BlockDriverState *bs); /* aio */ BlockDriverAIOCB *(*bdrv_aio_readv)(BlockDriverState *bs, int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, BlockDriverCompletionFunc *cb, void *opaque); BlockDriverAIOCB *(*bdrv_aio_writev)(BlockDriverState *bs, int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, BlockDriverCompletionFunc *cb, void *opaque); BlockDriverAIOCB *(*bdrv_aio_flush)(BlockDriverState *bs, BlockDriverCompletionFunc *cb, void *opaque); BlockDriverAIOCB *(*bdrv_aio_discard)(BlockDriverState *bs, int64_t sector_num, int nb_sectors, BlockDriverCompletionFunc *cb, void *opaque); int coroutine_fn (*bdrv_co_readv)(BlockDriverState *bs, int64_t sector_num, int nb_sectors, QEMUIOVector *qiov); int coroutine_fn (*bdrv_co_writev)(BlockDriverState *bs, int64_t sector_num, int nb_sectors, QEMUIOVector *qiov); /* * Efficiently zero a region of the disk image. Typically an image format * would use a compact metadata representation to implement this. This * function pointer may be NULL and .bdrv_co_writev() will be called * instead. */ int coroutine_fn (*bdrv_co_write_zeroes)(BlockDriverState *bs, int64_t sector_num, int nb_sectors); int coroutine_fn (*bdrv_co_discard)(BlockDriverState *bs, int64_t sector_num, int nb_sectors); int coroutine_fn (*bdrv_co_is_allocated)(BlockDriverState *bs, int64_t sector_num, int nb_sectors, int *pnum); /* * Invalidate any cached meta-data. */ void (*bdrv_invalidate_cache)(BlockDriverState *bs); /* * Flushes all data that was already written to the OS all the way down to * the disk (for example raw-posix calls fsync()). */ int coroutine_fn (*bdrv_co_flush_to_disk)(BlockDriverState *bs); /* * Flushes all internal caches to the OS. The data may still sit in a * writeback cache of the host OS, but it will survive a crash of the qemu * process. */ int coroutine_fn (*bdrv_co_flush_to_os)(BlockDriverState *bs); const char *protocol_name; int (*bdrv_truncate)(BlockDriverState *bs, int64_t offset); int64_t (*bdrv_getlength)(BlockDriverState *bs); int64_t (*bdrv_get_allocated_file_size)(BlockDriverState *bs); int (*bdrv_write_compressed)(BlockDriverState *bs, int64_t sector_num, const uint8_t *buf, int nb_sectors); int (*bdrv_snapshot_create)(BlockDriverState *bs, QEMUSnapshotInfo *sn_info); int (*bdrv_snapshot_goto)(BlockDriverState *bs, const char *snapshot_id); int (*bdrv_snapshot_delete)(BlockDriverState *bs, const char *snapshot_id); int (*bdrv_snapshot_list)(BlockDriverState *bs, QEMUSnapshotInfo **psn_info); int (*bdrv_snapshot_load_tmp)(BlockDriverState *bs, const char *snapshot_name); int (*bdrv_get_info)(BlockDriverState *bs, BlockDriverInfo *bdi); int (*bdrv_save_vmstate)(BlockDriverState *bs, const uint8_t *buf, int64_t pos, int size); int (*bdrv_load_vmstate)(BlockDriverState *bs, uint8_t *buf, int64_t pos, int size); int (*bdrv_change_backing_file)(BlockDriverState *bs, const char *backing_file, const char *backing_fmt); /* removable device specific */ int (*bdrv_is_inserted)(BlockDriverState *bs); int (*bdrv_media_changed)(BlockDriverState *bs); void (*bdrv_eject)(BlockDriverState *bs, bool eject_flag); void (*bdrv_lock_medium)(BlockDriverState *bs, bool locked); /* to control generic scsi devices */ int (*bdrv_ioctl)(BlockDriverState *bs, unsigned long int req, void *buf); BlockDriverAIOCB *(*bdrv_aio_ioctl)(BlockDriverState *bs, unsigned long int req, void *buf, BlockDriverCompletionFunc *cb, void *opaque); /* List of options for creating images, terminated by name == NULL */ QEMUOptionParameter *create_options; /* * Returns 0 for completed check, -errno for internal errors. * The check results are stored in result. */ int (*bdrv_check)(BlockDriverState* bs, BdrvCheckResult *result, BdrvCheckMode fix); void (*bdrv_debug_event)(BlockDriverState *bs, BlkDebugEvent event); /* * Returns 1 if newly created images are guaranteed to contain only * zeros, 0 otherwise. */ int (*bdrv_has_zero_init)(BlockDriverState *bs); QLIST_ENTRY(BlockDriver) list; }; /* * Note: the function bdrv_append() copies and swaps contents of * BlockDriverStates, so if you add new fields to this struct, please * inspect bdrv_append() to determine if the new fields need to be * copied as well. */ struct BlockDriverState { int64_t total_sectors; /* if we are reading a disk image, give its size in sectors */ int read_only; /* if true, the media is read only */ int keep_read_only; /* if true, the media was requested to stay read only */ int open_flags; /* flags used to open the file, re-used for re-open */ int encrypted; /* if true, the media is encrypted */ int valid_key; /* if true, a valid encryption key has been set */ int sg; /* if true, the device is a /dev/sg* */ int copy_on_read; /* if true, copy read backing sectors into image note this is a reference count */ BlockDriver *drv; /* NULL means no media */ void *opaque; void *dev; /* attached device model, if any */ /* TODO change to DeviceState when all users are qdevified */ const BlockDevOps *dev_ops; void *dev_opaque; char filename[1024]; char backing_file[1024]; /* if non zero, the image is a diff of this file image */ char backing_format[16]; /* if non-zero and backing_file exists */ int is_temporary; BlockDriverState *backing_hd; BlockDriverState *file; /* number of in-flight copy-on-read requests */ unsigned int copy_on_read_in_flight; /* the time for latest disk I/O */ int64_t slice_time; int64_t slice_start; int64_t slice_end; BlockIOLimit io_limits; BlockIOBaseValue io_base; CoQueue throttled_reqs; QEMUTimer *block_timer; bool io_limits_enabled; /* I/O stats (display with "info blockstats"). */ uint64_t nr_bytes[BDRV_MAX_IOTYPE]; uint64_t nr_ops[BDRV_MAX_IOTYPE]; uint64_t total_time_ns[BDRV_MAX_IOTYPE]; uint64_t wr_highest_sector; /* Whether the disk can expand beyond total_sectors */ int growable; /* the memory alignment required for the buffers handled by this driver */ int buffer_alignment; /* do we need to tell the quest if we have a volatile write cache? */ int enable_write_cache; /* NOTE: the following infos are only hints for real hardware drivers. They are not used by the block driver */ BlockErrorAction on_read_error, on_write_error; bool iostatus_enabled; BlockDeviceIoStatus iostatus; char device_name[32]; unsigned long *dirty_bitmap; int64_t dirty_count; int in_use; /* users other than guest access, eg. block migration */ QTAILQ_ENTRY(BlockDriverState) list; QLIST_HEAD(, BdrvTrackedRequest) tracked_requests; /* long-running background operation */ BlockJob *job; }; int get_tmp_filename(char *filename, int size); void bdrv_set_io_limits(BlockDriverState *bs, BlockIOLimit *io_limits); #ifdef _WIN32 int is_windows_drive(const char *filename); #endif /** * block_job_create: * @job_type: The class object for the newly-created job. * @bs: The block * @speed: The maximum speed, in bytes per second, or 0 for unlimited. * @cb: Completion function for the job. * @opaque: Opaque pointer value passed to @cb. * @errp: Error object. * * Create a new long-running block device job and return it. The job * will call @cb asynchronously when the job completes. Note that * @bs may have been closed at the time the @cb it is called. If * this is the case, the job may be reported as either cancelled or * completed. * * This function is not part of the public job interface; it should be * called from a wrapper that is specific to the job type. */ void *block_job_create(const BlockJobType *job_type, BlockDriverState *bs, int64_t speed, BlockDriverCompletionFunc *cb, void *opaque, Error **errp); /** * block_job_sleep_ns: * @job: The job that calls the function. * @clock: The clock to sleep on. * @ns: How many nanoseconds to stop for. * * Put the job to sleep (assuming that it wasn't canceled) for @ns * nanoseconds. Canceling the job will interrupt the wait immediately. */ void block_job_sleep_ns(BlockJob *job, QEMUClock *clock, int64_t ns); /** * block_job_complete: * @job: The job being completed. * @ret: The status code. * * Call the completion function that was registered at creation time, and * free @job. */ void block_job_complete(BlockJob *job, int ret); /** * block_job_set_speed: * @job: The job to set the speed for. * @speed: The new value * @errp: Error object. * * Set a rate-limiting parameter for the job; the actual meaning may * vary depending on the job type. */ void block_job_set_speed(BlockJob *job, int64_t speed, Error **errp); /** * block_job_cancel: * @job: The job to be canceled. * * Asynchronously cancel the specified job. */ void block_job_cancel(BlockJob *job); /** * block_job_is_cancelled: * @job: The job being queried. * * Returns whether the job is scheduled for cancellation. */ bool block_job_is_cancelled(BlockJob *job); /** * block_job_cancel: * @job: The job to be canceled. * * Asynchronously cancel the job and wait for it to reach a quiescent * state. Note that the completion callback will still be called * asynchronously, hence it is *not* valid to call #bdrv_delete * immediately after #block_job_cancel_sync. Users of block jobs * will usually protect the BlockDriverState objects with a reference * count, should this be a concern. * * Returns the return value from the job if the job actually completed * during the call, or -ECANCELED if it was canceled. */ int block_job_cancel_sync(BlockJob *job); /** * stream_start: * @bs: Block device to operate on. * @base: Block device that will become the new base, or %NULL to * flatten the whole backing file chain onto @bs. * @base_id: The file name that will be written to @bs as the new * backing file if the job completes. Ignored if @base is %NULL. * @speed: The maximum speed, in bytes per second, or 0 for unlimited. * @cb: Completion function for the job. * @opaque: Opaque pointer value passed to @cb. * @errp: Error object. * * Start a streaming operation on @bs. Clusters that are unallocated * in @bs, but allocated in any image between @base and @bs (both * exclusive) will be written to @bs. At the end of a successful * streaming job, the backing file of @bs will be changed to * @base_id in the written image and to @base in the live BlockDriverState. */ void stream_start(BlockDriverState *bs, BlockDriverState *base, const char *base_id, int64_t speed, BlockDriverCompletionFunc *cb, void *opaque, Error **errp); #endif /* BLOCK_INT_H */