qemu/block/block-backend.c
Peter Lieven ca78ecfa72 block: add blk_abort_aio_request
Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 1447345846-15624-3-git-send-email-pl@kamp.de
Signed-off-by: John Snow <jsnow@redhat.com>
2015-11-17 15:06:21 -05:00

1277 lines
32 KiB
C

/*
* QEMU Block backends
*
* Copyright (C) 2014 Red Hat, Inc.
*
* Authors:
* Markus Armbruster <armbru@redhat.com>,
*
* This work is licensed under the terms of the GNU LGPL, version 2.1
* or later. See the COPYING.LIB file in the top-level directory.
*/
#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; /* 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);
/* All the BlockBackends (except for hidden ones) */
static QTAILQ_HEAD(, BlockBackend) blk_backends =
QTAILQ_HEAD_INITIALIZER(blk_backends);
/*
* Create a new BlockBackend with @name, with a reference count of one.
* @name must not be null or empty.
* Fail if a BlockBackend with this name already exists.
* Store an error through @errp on failure, unless it's null.
* Return the new BlockBackend on success, null on failure.
*/
BlockBackend *blk_new(const char *name, Error **errp)
{
BlockBackend *blk;
assert(name && name[0]);
if (!id_wellformed(name)) {
error_setg(errp, "Invalid device name");
return NULL;
}
if (blk_by_name(name)) {
error_setg(errp, "Device with id '%s' already exists", name);
return NULL;
}
if (bdrv_find_node(name)) {
error_setg(errp,
"Device name '%s' conflicts with an existing node name",
name);
return NULL;
}
blk = g_new0(BlockBackend, 1);
blk->name = g_strdup(name);
blk->refcnt = 1;
QTAILQ_INSERT_TAIL(&blk_backends, blk, link);
return blk;
}
/*
* Create a new BlockBackend with a new BlockDriverState attached.
* Otherwise just like blk_new(), which see.
*/
BlockBackend *blk_new_with_bs(const char *name, Error **errp)
{
BlockBackend *blk;
BlockDriverState *bs;
blk = blk_new(name, errp);
if (!blk) {
return NULL;
}
bs = bdrv_new_root();
blk->bs = bs;
bs->blk = blk;
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;
}
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);
}
static void drive_info_del(DriveInfo *dinfo)
{
if (!dinfo) {
return;
}
qemu_opts_del(dinfo->opts);
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.
*/
void blk_ref(BlockBackend *blk)
{
blk->refcnt++;
}
/*
* Decrement @blk's reference count.
* If this drops it to zero, destroy @blk.
* For convenience, do nothing if @blk is null.
*/
void blk_unref(BlockBackend *blk)
{
if (blk) {
assert(blk->refcnt > 0);
if (!--blk->refcnt) {
blk_delete(blk);
}
}
}
/*
* Return the BlockBackend after @blk.
* If @blk is null, return the first one.
* Else, return @blk's next sibling, which may be null.
*
* To iterate over all BlockBackends, do
* for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
* ...
* }
*/
BlockBackend *blk_next(BlockBackend *blk)
{
return blk ? QTAILQ_NEXT(blk, link) : QTAILQ_FIRST(&blk_backends);
}
/*
* Return @blk's name, a non-null string.
* Wart: the name is empty iff @blk has been hidden with
* blk_hide_on_behalf_of_hmp_drive_del().
*/
const char *blk_name(BlockBackend *blk)
{
return blk->name;
}
/*
* Return the BlockBackend with name @name if it exists, else null.
* @name must not be null.
*/
BlockBackend *blk_by_name(const char *name)
{
BlockBackend *blk;
assert(name);
QTAILQ_FOREACH(blk, &blk_backends, link) {
if (!strcmp(name, blk->name)) {
return blk;
}
}
return NULL;
}
/*
* Return the BlockDriverState attached to @blk if any, else null.
*/
BlockDriverState *blk_bs(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.
*/
DriveInfo *blk_legacy_dinfo(BlockBackend *blk)
{
return blk->legacy_dinfo;
}
/*
* Set @blk's DriveInfo to @dinfo, and return it.
* @blk must not have a DriveInfo set already.
* No other BlockBackend may have the same DriveInfo set.
*/
DriveInfo *blk_set_legacy_dinfo(BlockBackend *blk, DriveInfo *dinfo)
{
assert(!blk->legacy_dinfo);
return blk->legacy_dinfo = dinfo;
}
/*
* Return the BlockBackend with DriveInfo @dinfo.
* It must exist.
*/
BlockBackend *blk_by_legacy_dinfo(DriveInfo *dinfo)
{
BlockBackend *blk;
QTAILQ_FOREACH(blk, &blk_backends, link) {
if (blk->legacy_dinfo == dinfo) {
return blk;
}
}
abort();
}
/*
* Hide @blk.
* @blk must not have been hidden already.
* Make attached BlockDriverState, if any, anonymous.
* Once hidden, @blk is invisible to all functions that don't receive
* it as argument. For example, blk_by_name() won't return it.
* Strictly for use by do_drive_del().
* TODO get rid of it!
*/
void blk_hide_on_behalf_of_hmp_drive_del(BlockBackend *blk)
{
QTAILQ_REMOVE(&blk_backends, blk, link);
blk->name[0] = 0;
if (blk->bs) {
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);
}
BlockAIOCB *blk_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 blk_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 blk_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 blk_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 blk_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 blk_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 blk_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;
}