#include "sysemu/block-backend.h"
#include "block/block_int.h"
+#include "block/blockjob.h"
+#include "block/throttle-groups.h"
#include "sysemu/blockdev.h"
+#include "sysemu/sysemu.h"
+#include "qapi-event.h"
+
+/* Number of coroutines to reserve per attached device model */
+#define COROUTINE_POOL_RESERVATION 64
+
+static AioContext *blk_aiocb_get_aio_context(BlockAIOCB *acb);
struct BlockBackend {
char *name;
int refcnt;
BlockDriverState *bs;
- DriveInfo *legacy_dinfo;
+ DriveInfo *legacy_dinfo; /* null unless created by drive_new() */
QTAILQ_ENTRY(BlockBackend) link; /* for blk_backends */
+
+ void *dev; /* attached device model, if any */
+ /* TODO change to DeviceState when all users are qdevified */
+ const BlockDevOps *dev_ops;
+ void *dev_opaque;
+
+ /* the block size for which the guest device expects atomicity */
+ int guest_block_size;
+
+ /* If the BDS tree is removed, some of its options are stored here (which
+ * can be used to restore those options in the new BDS on insert) */
+ BlockBackendRootState root_state;
+
+ /* I/O stats (display with "info blockstats"). */
+ BlockAcctStats stats;
+
+ BlockdevOnError on_read_error, on_write_error;
+ bool iostatus_enabled;
+ BlockDeviceIoStatus iostatus;
+};
+
+typedef struct BlockBackendAIOCB {
+ BlockAIOCB common;
+ QEMUBH *bh;
+ BlockBackend *blk;
+ int ret;
+} BlockBackendAIOCB;
+
+static const AIOCBInfo block_backend_aiocb_info = {
+ .get_aio_context = blk_aiocb_get_aio_context,
+ .aiocb_size = sizeof(BlockBackendAIOCB),
};
static void drive_info_del(DriveInfo *dinfo);
return blk;
}
+/*
+ * Calls blk_new_with_bs() and then calls bdrv_open() on the BlockDriverState.
+ *
+ * Just as with bdrv_open(), after having called this function the reference to
+ * @options belongs to the block layer (even on failure).
+ *
+ * TODO: Remove @filename and @flags; it should be possible to specify a whole
+ * BDS tree just by specifying the @options QDict (or @reference,
+ * alternatively). At the time of adding this function, this is not possible,
+ * though, so callers of this function have to be able to specify @filename and
+ * @flags.
+ */
+BlockBackend *blk_new_open(const char *name, const char *filename,
+ const char *reference, QDict *options, int flags,
+ Error **errp)
+{
+ BlockBackend *blk;
+ int ret;
+
+ blk = blk_new_with_bs(name, errp);
+ if (!blk) {
+ QDECREF(options);
+ return NULL;
+ }
+
+ ret = bdrv_open(&blk->bs, filename, reference, options, flags, errp);
+ if (ret < 0) {
+ blk_unref(blk);
+ return NULL;
+ }
+
+ return blk;
+}
+
static void blk_delete(BlockBackend *blk)
{
assert(!blk->refcnt);
+ assert(!blk->dev);
if (blk->bs) {
assert(blk->bs->blk == blk);
blk->bs->blk = NULL;
bdrv_unref(blk->bs);
blk->bs = NULL;
}
- /* Avoid double-remove after blk_hide_on_behalf_of_do_drive_del() */
+ if (blk->root_state.throttle_state) {
+ g_free(blk->root_state.throttle_group);
+ throttle_group_unref(blk->root_state.throttle_state);
+ }
+ /* Avoid double-remove after blk_hide_on_behalf_of_hmp_drive_del() */
if (blk->name[0]) {
QTAILQ_REMOVE(&blk_backends, blk, link);
}
g_free(blk->name);
drive_info_del(blk->legacy_dinfo);
+ block_acct_cleanup(&blk->stats);
g_free(blk);
}
return;
}
qemu_opts_del(dinfo->opts);
- g_free(dinfo->id);
g_free(dinfo->serial);
g_free(dinfo);
}
+int blk_get_refcnt(BlockBackend *blk)
+{
+ return blk ? blk->refcnt : 0;
+}
+
/*
* Increment @blk's reference count.
* @blk must not be null.
/*
* Return @blk's name, a non-null string.
* Wart: the name is empty iff @blk has been hidden with
- * blk_hide_on_behalf_of_do_drive_del().
+ * blk_hide_on_behalf_of_hmp_drive_del().
*/
const char *blk_name(BlockBackend *blk)
{
return blk->bs;
}
+/*
+ * Changes the BlockDriverState attached to @blk
+ */
+void blk_set_bs(BlockBackend *blk, BlockDriverState *bs)
+{
+ bdrv_ref(bs);
+
+ if (blk->bs) {
+ blk->bs->blk = NULL;
+ bdrv_unref(blk->bs);
+ }
+ assert(bs->blk == NULL);
+
+ blk->bs = bs;
+ bs->blk = blk;
+}
+
/*
* Return @blk's DriveInfo if any, else null.
*/
* Strictly for use by do_drive_del().
* TODO get rid of it!
*/
-void blk_hide_on_behalf_of_do_drive_del(BlockBackend *blk)
+void blk_hide_on_behalf_of_hmp_drive_del(BlockBackend *blk)
{
QTAILQ_REMOVE(&blk_backends, blk, link);
blk->name[0] = 0;
bdrv_make_anon(blk->bs);
}
}
+
+/*
+ * Disassociates the currently associated BlockDriverState from @blk.
+ */
+void blk_remove_bs(BlockBackend *blk)
+{
+ blk_update_root_state(blk);
+
+ blk->bs->blk = NULL;
+ bdrv_unref(blk->bs);
+ blk->bs = NULL;
+}
+
+/*
+ * Associates a new BlockDriverState with @blk.
+ */
+void blk_insert_bs(BlockBackend *blk, BlockDriverState *bs)
+{
+ assert(!blk->bs && !bs->blk);
+ bdrv_ref(bs);
+ blk->bs = bs;
+ bs->blk = blk;
+}
+
+/*
+ * Attach device model @dev to @blk.
+ * Return 0 on success, -EBUSY when a device model is attached already.
+ */
+int blk_attach_dev(BlockBackend *blk, void *dev)
+/* TODO change to DeviceState *dev when all users are qdevified */
+{
+ if (blk->dev) {
+ return -EBUSY;
+ }
+ blk_ref(blk);
+ blk->dev = dev;
+ blk_iostatus_reset(blk);
+ return 0;
+}
+
+/*
+ * Attach device model @dev to @blk.
+ * @blk must not have a device model attached already.
+ * TODO qdevified devices don't use this, remove when devices are qdevified
+ */
+void blk_attach_dev_nofail(BlockBackend *blk, void *dev)
+{
+ if (blk_attach_dev(blk, dev) < 0) {
+ abort();
+ }
+}
+
+/*
+ * Detach device model @dev from @blk.
+ * @dev must be currently attached to @blk.
+ */
+void blk_detach_dev(BlockBackend *blk, void *dev)
+/* TODO change to DeviceState *dev when all users are qdevified */
+{
+ assert(blk->dev == dev);
+ blk->dev = NULL;
+ blk->dev_ops = NULL;
+ blk->dev_opaque = NULL;
+ blk->guest_block_size = 512;
+ blk_unref(blk);
+}
+
+/*
+ * Return the device model attached to @blk if any, else null.
+ */
+void *blk_get_attached_dev(BlockBackend *blk)
+/* TODO change to return DeviceState * when all users are qdevified */
+{
+ return blk->dev;
+}
+
+/*
+ * Set @blk's device model callbacks to @ops.
+ * @opaque is the opaque argument to pass to the callbacks.
+ * This is for use by device models.
+ */
+void blk_set_dev_ops(BlockBackend *blk, const BlockDevOps *ops,
+ void *opaque)
+{
+ blk->dev_ops = ops;
+ blk->dev_opaque = opaque;
+}
+
+/*
+ * Notify @blk's attached device model of media change.
+ * If @load is true, notify of media load.
+ * Else, notify of media eject.
+ * Also send DEVICE_TRAY_MOVED events as appropriate.
+ */
+void blk_dev_change_media_cb(BlockBackend *blk, bool load)
+{
+ if (blk->dev_ops && blk->dev_ops->change_media_cb) {
+ bool tray_was_open, tray_is_open;
+
+ tray_was_open = blk_dev_is_tray_open(blk);
+ blk->dev_ops->change_media_cb(blk->dev_opaque, load);
+ tray_is_open = blk_dev_is_tray_open(blk);
+
+ if (tray_was_open != tray_is_open) {
+ qapi_event_send_device_tray_moved(blk_name(blk), tray_is_open,
+ &error_abort);
+ }
+ }
+}
+
+/*
+ * Does @blk's attached device model have removable media?
+ * %true if no device model is attached.
+ */
+bool blk_dev_has_removable_media(BlockBackend *blk)
+{
+ return !blk->dev || (blk->dev_ops && blk->dev_ops->change_media_cb);
+}
+
+/*
+ * Notify @blk's attached device model of a media eject request.
+ * If @force is true, the medium is about to be yanked out forcefully.
+ */
+void blk_dev_eject_request(BlockBackend *blk, bool force)
+{
+ if (blk->dev_ops && blk->dev_ops->eject_request_cb) {
+ blk->dev_ops->eject_request_cb(blk->dev_opaque, force);
+ }
+}
+
+/*
+ * Does @blk's attached device model have a tray, and is it open?
+ */
+bool blk_dev_is_tray_open(BlockBackend *blk)
+{
+ if (blk->dev_ops && blk->dev_ops->is_tray_open) {
+ return blk->dev_ops->is_tray_open(blk->dev_opaque);
+ }
+ return false;
+}
+
+/*
+ * Does @blk's attached device model have the medium locked?
+ * %false if the device model has no such lock.
+ */
+bool blk_dev_is_medium_locked(BlockBackend *blk)
+{
+ if (blk->dev_ops && blk->dev_ops->is_medium_locked) {
+ return blk->dev_ops->is_medium_locked(blk->dev_opaque);
+ }
+ return false;
+}
+
+/*
+ * Notify @blk's attached device model of a backend size change.
+ */
+void blk_dev_resize_cb(BlockBackend *blk)
+{
+ if (blk->dev_ops && blk->dev_ops->resize_cb) {
+ blk->dev_ops->resize_cb(blk->dev_opaque);
+ }
+}
+
+void blk_iostatus_enable(BlockBackend *blk)
+{
+ blk->iostatus_enabled = true;
+ blk->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
+}
+
+/* The I/O status is only enabled if the drive explicitly
+ * enables it _and_ the VM is configured to stop on errors */
+bool blk_iostatus_is_enabled(const BlockBackend *blk)
+{
+ return (blk->iostatus_enabled &&
+ (blk->on_write_error == BLOCKDEV_ON_ERROR_ENOSPC ||
+ blk->on_write_error == BLOCKDEV_ON_ERROR_STOP ||
+ blk->on_read_error == BLOCKDEV_ON_ERROR_STOP));
+}
+
+BlockDeviceIoStatus blk_iostatus(const BlockBackend *blk)
+{
+ return blk->iostatus;
+}
+
+void blk_iostatus_disable(BlockBackend *blk)
+{
+ blk->iostatus_enabled = false;
+}
+
+void blk_iostatus_reset(BlockBackend *blk)
+{
+ if (blk_iostatus_is_enabled(blk)) {
+ blk->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
+ if (blk->bs && blk->bs->job) {
+ block_job_iostatus_reset(blk->bs->job);
+ }
+ }
+}
+
+void blk_iostatus_set_err(BlockBackend *blk, int error)
+{
+ assert(blk_iostatus_is_enabled(blk));
+ if (blk->iostatus == BLOCK_DEVICE_IO_STATUS_OK) {
+ blk->iostatus = error == ENOSPC ? BLOCK_DEVICE_IO_STATUS_NOSPACE :
+ BLOCK_DEVICE_IO_STATUS_FAILED;
+ }
+}
+
+static int blk_check_byte_request(BlockBackend *blk, int64_t offset,
+ size_t size)
+{
+ int64_t len;
+
+ if (size > INT_MAX) {
+ return -EIO;
+ }
+
+ if (!blk_is_available(blk)) {
+ return -ENOMEDIUM;
+ }
+
+ len = blk_getlength(blk);
+ if (len < 0) {
+ return len;
+ }
+
+ if (offset < 0) {
+ return -EIO;
+ }
+
+ if (offset > len || len - offset < size) {
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static int blk_check_request(BlockBackend *blk, int64_t sector_num,
+ int nb_sectors)
+{
+ if (sector_num < 0 || sector_num > INT64_MAX / BDRV_SECTOR_SIZE) {
+ return -EIO;
+ }
+
+ if (nb_sectors < 0 || nb_sectors > INT_MAX / BDRV_SECTOR_SIZE) {
+ return -EIO;
+ }
+
+ return blk_check_byte_request(blk, sector_num * BDRV_SECTOR_SIZE,
+ nb_sectors * BDRV_SECTOR_SIZE);
+}
+
+int blk_read(BlockBackend *blk, int64_t sector_num, uint8_t *buf,
+ int nb_sectors)
+{
+ int ret = blk_check_request(blk, sector_num, nb_sectors);
+ if (ret < 0) {
+ return ret;
+ }
+
+ return bdrv_read(blk->bs, sector_num, buf, nb_sectors);
+}
+
+int blk_read_unthrottled(BlockBackend *blk, int64_t sector_num, uint8_t *buf,
+ int nb_sectors)
+{
+ int ret = blk_check_request(blk, sector_num, nb_sectors);
+ if (ret < 0) {
+ return ret;
+ }
+
+ return bdrv_read_unthrottled(blk->bs, sector_num, buf, nb_sectors);
+}
+
+int blk_write(BlockBackend *blk, int64_t sector_num, const uint8_t *buf,
+ int nb_sectors)
+{
+ int ret = blk_check_request(blk, sector_num, nb_sectors);
+ if (ret < 0) {
+ return ret;
+ }
+
+ return bdrv_write(blk->bs, sector_num, buf, nb_sectors);
+}
+
+int blk_write_zeroes(BlockBackend *blk, int64_t sector_num,
+ int nb_sectors, BdrvRequestFlags flags)
+{
+ int ret = blk_check_request(blk, sector_num, nb_sectors);
+ if (ret < 0) {
+ return ret;
+ }
+
+ return bdrv_write_zeroes(blk->bs, sector_num, nb_sectors, flags);
+}
+
+static void error_callback_bh(void *opaque)
+{
+ struct BlockBackendAIOCB *acb = opaque;
+ qemu_bh_delete(acb->bh);
+ acb->common.cb(acb->common.opaque, acb->ret);
+ qemu_aio_unref(acb);
+}
+
+static BlockAIOCB *abort_aio_request(BlockBackend *blk, BlockCompletionFunc *cb,
+ void *opaque, int ret)
+{
+ struct BlockBackendAIOCB *acb;
+ QEMUBH *bh;
+
+ acb = blk_aio_get(&block_backend_aiocb_info, blk, cb, opaque);
+ acb->blk = blk;
+ acb->ret = ret;
+
+ bh = aio_bh_new(blk_get_aio_context(blk), error_callback_bh, acb);
+ acb->bh = bh;
+ qemu_bh_schedule(bh);
+
+ return &acb->common;
+}
+
+BlockAIOCB *blk_aio_write_zeroes(BlockBackend *blk, int64_t sector_num,
+ int nb_sectors, BdrvRequestFlags flags,
+ BlockCompletionFunc *cb, void *opaque)
+{
+ int ret = blk_check_request(blk, sector_num, nb_sectors);
+ if (ret < 0) {
+ return abort_aio_request(blk, cb, opaque, ret);
+ }
+
+ return bdrv_aio_write_zeroes(blk->bs, sector_num, nb_sectors, flags,
+ cb, opaque);
+}
+
+int blk_pread(BlockBackend *blk, int64_t offset, void *buf, int count)
+{
+ int ret = blk_check_byte_request(blk, offset, count);
+ if (ret < 0) {
+ return ret;
+ }
+
+ return bdrv_pread(blk->bs, offset, buf, count);
+}
+
+int blk_pwrite(BlockBackend *blk, int64_t offset, const void *buf, int count)
+{
+ int ret = blk_check_byte_request(blk, offset, count);
+ if (ret < 0) {
+ return ret;
+ }
+
+ return bdrv_pwrite(blk->bs, offset, buf, count);
+}
+
+int64_t blk_getlength(BlockBackend *blk)
+{
+ if (!blk_is_available(blk)) {
+ return -ENOMEDIUM;
+ }
+
+ return bdrv_getlength(blk->bs);
+}
+
+void blk_get_geometry(BlockBackend *blk, uint64_t *nb_sectors_ptr)
+{
+ if (!blk->bs) {
+ *nb_sectors_ptr = 0;
+ } else {
+ bdrv_get_geometry(blk->bs, nb_sectors_ptr);
+ }
+}
+
+int64_t blk_nb_sectors(BlockBackend *blk)
+{
+ if (!blk_is_available(blk)) {
+ return -ENOMEDIUM;
+ }
+
+ return bdrv_nb_sectors(blk->bs);
+}
+
+BlockAIOCB *blk_aio_readv(BlockBackend *blk, int64_t sector_num,
+ QEMUIOVector *iov, int nb_sectors,
+ BlockCompletionFunc *cb, void *opaque)
+{
+ int ret = blk_check_request(blk, sector_num, nb_sectors);
+ if (ret < 0) {
+ return abort_aio_request(blk, cb, opaque, ret);
+ }
+
+ return bdrv_aio_readv(blk->bs, sector_num, iov, nb_sectors, cb, opaque);
+}
+
+BlockAIOCB *blk_aio_writev(BlockBackend *blk, int64_t sector_num,
+ QEMUIOVector *iov, int nb_sectors,
+ BlockCompletionFunc *cb, void *opaque)
+{
+ int ret = blk_check_request(blk, sector_num, nb_sectors);
+ if (ret < 0) {
+ return abort_aio_request(blk, cb, opaque, ret);
+ }
+
+ return bdrv_aio_writev(blk->bs, sector_num, iov, nb_sectors, cb, opaque);
+}
+
+BlockAIOCB *blk_aio_flush(BlockBackend *blk,
+ BlockCompletionFunc *cb, void *opaque)
+{
+ if (!blk_is_available(blk)) {
+ return abort_aio_request(blk, cb, opaque, -ENOMEDIUM);
+ }
+
+ return bdrv_aio_flush(blk->bs, cb, opaque);
+}
+
+BlockAIOCB *blk_aio_discard(BlockBackend *blk,
+ int64_t sector_num, int nb_sectors,
+ BlockCompletionFunc *cb, void *opaque)
+{
+ int ret = blk_check_request(blk, sector_num, nb_sectors);
+ if (ret < 0) {
+ return abort_aio_request(blk, cb, opaque, ret);
+ }
+
+ return bdrv_aio_discard(blk->bs, sector_num, nb_sectors, cb, opaque);
+}
+
+void blk_aio_cancel(BlockAIOCB *acb)
+{
+ bdrv_aio_cancel(acb);
+}
+
+void blk_aio_cancel_async(BlockAIOCB *acb)
+{
+ bdrv_aio_cancel_async(acb);
+}
+
+int blk_aio_multiwrite(BlockBackend *blk, BlockRequest *reqs, int num_reqs)
+{
+ int i, ret;
+
+ for (i = 0; i < num_reqs; i++) {
+ ret = blk_check_request(blk, reqs[i].sector, reqs[i].nb_sectors);
+ if (ret < 0) {
+ return ret;
+ }
+ }
+
+ return bdrv_aio_multiwrite(blk->bs, reqs, num_reqs);
+}
+
+int blk_ioctl(BlockBackend *blk, unsigned long int req, void *buf)
+{
+ if (!blk_is_available(blk)) {
+ return -ENOMEDIUM;
+ }
+
+ return bdrv_ioctl(blk->bs, req, buf);
+}
+
+BlockAIOCB *blk_aio_ioctl(BlockBackend *blk, unsigned long int req, void *buf,
+ BlockCompletionFunc *cb, void *opaque)
+{
+ if (!blk_is_available(blk)) {
+ return abort_aio_request(blk, cb, opaque, -ENOMEDIUM);
+ }
+
+ return bdrv_aio_ioctl(blk->bs, req, buf, cb, opaque);
+}
+
+int blk_co_discard(BlockBackend *blk, int64_t sector_num, int nb_sectors)
+{
+ int ret = blk_check_request(blk, sector_num, nb_sectors);
+ if (ret < 0) {
+ return ret;
+ }
+
+ return bdrv_co_discard(blk->bs, sector_num, nb_sectors);
+}
+
+int blk_co_flush(BlockBackend *blk)
+{
+ if (!blk_is_available(blk)) {
+ return -ENOMEDIUM;
+ }
+
+ return bdrv_co_flush(blk->bs);
+}
+
+int blk_flush(BlockBackend *blk)
+{
+ if (!blk_is_available(blk)) {
+ return -ENOMEDIUM;
+ }
+
+ return bdrv_flush(blk->bs);
+}
+
+int blk_flush_all(void)
+{
+ return bdrv_flush_all();
+}
+
+void blk_drain(BlockBackend *blk)
+{
+ if (blk->bs) {
+ bdrv_drain(blk->bs);
+ }
+}
+
+void blk_drain_all(void)
+{
+ bdrv_drain_all();
+}
+
+void blk_set_on_error(BlockBackend *blk, BlockdevOnError on_read_error,
+ BlockdevOnError on_write_error)
+{
+ blk->on_read_error = on_read_error;
+ blk->on_write_error = on_write_error;
+}
+
+BlockdevOnError blk_get_on_error(BlockBackend *blk, bool is_read)
+{
+ return is_read ? blk->on_read_error : blk->on_write_error;
+}
+
+BlockErrorAction blk_get_error_action(BlockBackend *blk, bool is_read,
+ int error)
+{
+ BlockdevOnError on_err = blk_get_on_error(blk, is_read);
+
+ switch (on_err) {
+ case BLOCKDEV_ON_ERROR_ENOSPC:
+ return (error == ENOSPC) ?
+ BLOCK_ERROR_ACTION_STOP : BLOCK_ERROR_ACTION_REPORT;
+ case BLOCKDEV_ON_ERROR_STOP:
+ return BLOCK_ERROR_ACTION_STOP;
+ case BLOCKDEV_ON_ERROR_REPORT:
+ return BLOCK_ERROR_ACTION_REPORT;
+ case BLOCKDEV_ON_ERROR_IGNORE:
+ return BLOCK_ERROR_ACTION_IGNORE;
+ default:
+ abort();
+ }
+}
+
+static void send_qmp_error_event(BlockBackend *blk,
+ BlockErrorAction action,
+ bool is_read, int error)
+{
+ IoOperationType optype;
+
+ optype = is_read ? IO_OPERATION_TYPE_READ : IO_OPERATION_TYPE_WRITE;
+ qapi_event_send_block_io_error(blk_name(blk), optype, action,
+ blk_iostatus_is_enabled(blk),
+ error == ENOSPC, strerror(error),
+ &error_abort);
+}
+
+/* This is done by device models because, while the block layer knows
+ * about the error, it does not know whether an operation comes from
+ * the device or the block layer (from a job, for example).
+ */
+void blk_error_action(BlockBackend *blk, BlockErrorAction action,
+ bool is_read, int error)
+{
+ assert(error >= 0);
+
+ if (action == BLOCK_ERROR_ACTION_STOP) {
+ /* First set the iostatus, so that "info block" returns an iostatus
+ * that matches the events raised so far (an additional error iostatus
+ * is fine, but not a lost one).
+ */
+ blk_iostatus_set_err(blk, error);
+
+ /* Then raise the request to stop the VM and the event.
+ * qemu_system_vmstop_request_prepare has two effects. First,
+ * it ensures that the STOP event always comes after the
+ * BLOCK_IO_ERROR event. Second, it ensures that even if management
+ * can observe the STOP event and do a "cont" before the STOP
+ * event is issued, the VM will not stop. In this case, vm_start()
+ * also ensures that the STOP/RESUME pair of events is emitted.
+ */
+ qemu_system_vmstop_request_prepare();
+ send_qmp_error_event(blk, action, is_read, error);
+ qemu_system_vmstop_request(RUN_STATE_IO_ERROR);
+ } else {
+ send_qmp_error_event(blk, action, is_read, error);
+ }
+}
+
+int blk_is_read_only(BlockBackend *blk)
+{
+ if (blk->bs) {
+ return bdrv_is_read_only(blk->bs);
+ } else {
+ return blk->root_state.read_only;
+ }
+}
+
+int blk_is_sg(BlockBackend *blk)
+{
+ if (!blk->bs) {
+ return 0;
+ }
+
+ return bdrv_is_sg(blk->bs);
+}
+
+int blk_enable_write_cache(BlockBackend *blk)
+{
+ if (blk->bs) {
+ return bdrv_enable_write_cache(blk->bs);
+ } else {
+ return !!(blk->root_state.open_flags & BDRV_O_CACHE_WB);
+ }
+}
+
+void blk_set_enable_write_cache(BlockBackend *blk, bool wce)
+{
+ if (blk->bs) {
+ bdrv_set_enable_write_cache(blk->bs, wce);
+ } else {
+ if (wce) {
+ blk->root_state.open_flags |= BDRV_O_CACHE_WB;
+ } else {
+ blk->root_state.open_flags &= ~BDRV_O_CACHE_WB;
+ }
+ }
+}
+
+void blk_invalidate_cache(BlockBackend *blk, Error **errp)
+{
+ if (!blk->bs) {
+ error_setg(errp, "Device '%s' has no medium", blk->name);
+ return;
+ }
+
+ bdrv_invalidate_cache(blk->bs, errp);
+}
+
+bool blk_is_inserted(BlockBackend *blk)
+{
+ return blk->bs && bdrv_is_inserted(blk->bs);
+}
+
+bool blk_is_available(BlockBackend *blk)
+{
+ return blk_is_inserted(blk) && !blk_dev_is_tray_open(blk);
+}
+
+void blk_lock_medium(BlockBackend *blk, bool locked)
+{
+ if (blk->bs) {
+ bdrv_lock_medium(blk->bs, locked);
+ }
+}
+
+void blk_eject(BlockBackend *blk, bool eject_flag)
+{
+ if (blk->bs) {
+ bdrv_eject(blk->bs, eject_flag);
+ }
+}
+
+int blk_get_flags(BlockBackend *blk)
+{
+ if (blk->bs) {
+ return bdrv_get_flags(blk->bs);
+ } else {
+ return blk->root_state.open_flags;
+ }
+}
+
+int blk_get_max_transfer_length(BlockBackend *blk)
+{
+ if (blk->bs) {
+ return blk->bs->bl.max_transfer_length;
+ } else {
+ return 0;
+ }
+}
+
+void blk_set_guest_block_size(BlockBackend *blk, int align)
+{
+ blk->guest_block_size = align;
+}
+
+void *blk_blockalign(BlockBackend *blk, size_t size)
+{
+ return qemu_blockalign(blk ? blk->bs : NULL, size);
+}
+
+bool blk_op_is_blocked(BlockBackend *blk, BlockOpType op, Error **errp)
+{
+ if (!blk->bs) {
+ return false;
+ }
+
+ return bdrv_op_is_blocked(blk->bs, op, errp);
+}
+
+void blk_op_unblock(BlockBackend *blk, BlockOpType op, Error *reason)
+{
+ if (blk->bs) {
+ bdrv_op_unblock(blk->bs, op, reason);
+ }
+}
+
+void blk_op_block_all(BlockBackend *blk, Error *reason)
+{
+ if (blk->bs) {
+ bdrv_op_block_all(blk->bs, reason);
+ }
+}
+
+void blk_op_unblock_all(BlockBackend *blk, Error *reason)
+{
+ if (blk->bs) {
+ bdrv_op_unblock_all(blk->bs, reason);
+ }
+}
+
+AioContext *blk_get_aio_context(BlockBackend *blk)
+{
+ if (blk->bs) {
+ return bdrv_get_aio_context(blk->bs);
+ } else {
+ return qemu_get_aio_context();
+ }
+}
+
+static AioContext *blk_aiocb_get_aio_context(BlockAIOCB *acb)
+{
+ BlockBackendAIOCB *blk_acb = DO_UPCAST(BlockBackendAIOCB, common, acb);
+ return blk_get_aio_context(blk_acb->blk);
+}
+
+void blk_set_aio_context(BlockBackend *blk, AioContext *new_context)
+{
+ if (blk->bs) {
+ bdrv_set_aio_context(blk->bs, new_context);
+ }
+}
+
+void blk_add_aio_context_notifier(BlockBackend *blk,
+ void (*attached_aio_context)(AioContext *new_context, void *opaque),
+ void (*detach_aio_context)(void *opaque), void *opaque)
+{
+ if (blk->bs) {
+ bdrv_add_aio_context_notifier(blk->bs, attached_aio_context,
+ detach_aio_context, opaque);
+ }
+}
+
+void blk_remove_aio_context_notifier(BlockBackend *blk,
+ void (*attached_aio_context)(AioContext *,
+ void *),
+ void (*detach_aio_context)(void *),
+ void *opaque)
+{
+ if (blk->bs) {
+ bdrv_remove_aio_context_notifier(blk->bs, attached_aio_context,
+ detach_aio_context, opaque);
+ }
+}
+
+void blk_add_close_notifier(BlockBackend *blk, Notifier *notify)
+{
+ if (blk->bs) {
+ bdrv_add_close_notifier(blk->bs, notify);
+ }
+}
+
+void blk_io_plug(BlockBackend *blk)
+{
+ if (blk->bs) {
+ bdrv_io_plug(blk->bs);
+ }
+}
+
+void blk_io_unplug(BlockBackend *blk)
+{
+ if (blk->bs) {
+ bdrv_io_unplug(blk->bs);
+ }
+}
+
+BlockAcctStats *blk_get_stats(BlockBackend *blk)
+{
+ return &blk->stats;
+}
+
+void *blk_aio_get(const AIOCBInfo *aiocb_info, BlockBackend *blk,
+ BlockCompletionFunc *cb, void *opaque)
+{
+ return qemu_aio_get(aiocb_info, blk_bs(blk), cb, opaque);
+}
+
+int coroutine_fn blk_co_write_zeroes(BlockBackend *blk, int64_t sector_num,
+ int nb_sectors, BdrvRequestFlags flags)
+{
+ int ret = blk_check_request(blk, sector_num, nb_sectors);
+ if (ret < 0) {
+ return ret;
+ }
+
+ return bdrv_co_write_zeroes(blk->bs, sector_num, nb_sectors, flags);
+}
+
+int blk_write_compressed(BlockBackend *blk, int64_t sector_num,
+ const uint8_t *buf, int nb_sectors)
+{
+ int ret = blk_check_request(blk, sector_num, nb_sectors);
+ if (ret < 0) {
+ return ret;
+ }
+
+ return bdrv_write_compressed(blk->bs, sector_num, buf, nb_sectors);
+}
+
+int blk_truncate(BlockBackend *blk, int64_t offset)
+{
+ if (!blk_is_available(blk)) {
+ return -ENOMEDIUM;
+ }
+
+ return bdrv_truncate(blk->bs, offset);
+}
+
+int blk_discard(BlockBackend *blk, int64_t sector_num, int nb_sectors)
+{
+ int ret = blk_check_request(blk, sector_num, nb_sectors);
+ if (ret < 0) {
+ return ret;
+ }
+
+ return bdrv_discard(blk->bs, sector_num, nb_sectors);
+}
+
+int blk_save_vmstate(BlockBackend *blk, const uint8_t *buf,
+ int64_t pos, int size)
+{
+ if (!blk_is_available(blk)) {
+ return -ENOMEDIUM;
+ }
+
+ return bdrv_save_vmstate(blk->bs, buf, pos, size);
+}
+
+int blk_load_vmstate(BlockBackend *blk, uint8_t *buf, int64_t pos, int size)
+{
+ if (!blk_is_available(blk)) {
+ return -ENOMEDIUM;
+ }
+
+ return bdrv_load_vmstate(blk->bs, buf, pos, size);
+}
+
+int blk_probe_blocksizes(BlockBackend *blk, BlockSizes *bsz)
+{
+ if (!blk_is_available(blk)) {
+ return -ENOMEDIUM;
+ }
+
+ return bdrv_probe_blocksizes(blk->bs, bsz);
+}
+
+int blk_probe_geometry(BlockBackend *blk, HDGeometry *geo)
+{
+ if (!blk_is_available(blk)) {
+ return -ENOMEDIUM;
+ }
+
+ return bdrv_probe_geometry(blk->bs, geo);
+}
+
+/*
+ * Updates the BlockBackendRootState object with data from the currently
+ * attached BlockDriverState.
+ */
+void blk_update_root_state(BlockBackend *blk)
+{
+ assert(blk->bs);
+
+ blk->root_state.open_flags = blk->bs->open_flags;
+ blk->root_state.read_only = blk->bs->read_only;
+ blk->root_state.detect_zeroes = blk->bs->detect_zeroes;
+
+ if (blk->root_state.throttle_group) {
+ g_free(blk->root_state.throttle_group);
+ throttle_group_unref(blk->root_state.throttle_state);
+ }
+ if (blk->bs->throttle_state) {
+ const char *name = throttle_group_get_name(blk->bs);
+ blk->root_state.throttle_group = g_strdup(name);
+ blk->root_state.throttle_state = throttle_group_incref(name);
+ } else {
+ blk->root_state.throttle_group = NULL;
+ blk->root_state.throttle_state = NULL;
+ }
+}
+
+/*
+ * Applies the information in the root state to the given BlockDriverState. This
+ * does not include the flags which have to be specified for bdrv_open(), use
+ * blk_get_open_flags_from_root_state() to inquire them.
+ */
+void blk_apply_root_state(BlockBackend *blk, BlockDriverState *bs)
+{
+ bs->detect_zeroes = blk->root_state.detect_zeroes;
+ if (blk->root_state.throttle_group) {
+ bdrv_io_limits_enable(bs, blk->root_state.throttle_group);
+ }
+}
+
+/*
+ * Returns the flags to be used for bdrv_open() of a BlockDriverState which is
+ * supposed to inherit the root state.
+ */
+int blk_get_open_flags_from_root_state(BlockBackend *blk)
+{
+ int bs_flags;
+
+ bs_flags = blk->root_state.read_only ? 0 : BDRV_O_RDWR;
+ bs_flags |= blk->root_state.open_flags & ~BDRV_O_RDWR;
+
+ return bs_flags;
+}
+
+BlockBackendRootState *blk_get_root_state(BlockBackend *blk)
+{
+ return &blk->root_state;
+}
projects / qemu.git / blobdiff