Re: [PATCH 09/18] Introduce event-tap.

[Yoshiaki Tamura <tamura.yoshiaki@lab.ntt.co.jp>]

ya su wrote:
> Yoshi:
>
>      I think event-tap is a great idea, it remove the reading from disk
> which will increase ft effiency much better as your plan in later
> series.
>
>      one question: IO read/write may dirty rams, but it is difficute to
> differ them from other dirty pages like caused by  running of
> softwares,  whether that means you need change all the emulated device
> realization?  actually I think it will not send too much rams caused
> by IO Read/Write in ram_save_live, but if It can event-tap IO
> read/write and replay on the other side, Does that means we don't need
> call qemu_savevm_state_full in ft transactoins?

I'm not expecting to remove qemu_savevm_state_full in the transaction.  Just 
reduce the number of pages to be transfered as a result.

Thanks,

Yoshi

>
> Green.
>
>
> 2011/3/9 Yoshiaki Tamura<tamura.yoshiaki@lab.ntt.co.jp>:
>> ya su wrote:
>>>
>>> 2011/3/8 Yoshiaki Tamura<tamura.yoshiaki@lab.ntt.co.jp>:
>>>>
>>>> ya su wrote:
>>>>>
>>>>> Yokshiaki:
>>>>>
>>>>>      event-tap record block and io wirte events, and replay these on
>>>>> the other side, so block_save_live is useless during the latter ft
>>>>> phase, right? if so, I think it need to process the following code in
>>>>> block_save_live function:
>>>>
>>>> Actually no.  It just replays the last events only.  We do have patches
>>>> that
>>>> enable block replication without using block live migration, like the way
>>>> you described above.  In that case, we disable block live migration when
>>>>   we
>>>> go into ft mode.  We're thinking to propose it after this series get
>>>> settled.
>>>
>>> so event-tap's objective is to initial a ft transaction, to start the
>>> sync. of ram/block/device states? if so, it need not change
>>> bdrv_aio_writev/bdrv_aio_flush normal process, on the other side it
>>> need not invokde bdrv_aio_writev either, right?
>>
>> Mostly yes, but because event-tap is queuing requests from block/net, it
>> needs to flush queued requests after the transaction on the primary side.
>>   On the secondary, it currently doesn't have to invoke bdrv_aio_writev as
>> you mentioned.  But will change soon to enable block replication with
>> event-tap.
>>
>>>
>>>>
>>>>>
>>>>>      if (stage == 1) {
>>>>>          init_blk_migration(mon, f);
>>>>>
>>>>>          /* start track dirty blocks */
>>>>>          set_dirty_tracking(1);
>>>>>      }
>>>>> --------------------------------------
>>>>> the following code will send block to the other side, as this will
>>>>> also be done by event-tap replay. I think it should placed in stage 3,
>>>>> before the assert line. (this may affect some stage 2 rate-limit
>>>>> then, so this can be placed in stage 2, though it looks ugly), another
>>>>> choice is to avoid the invocation of block_save_live, right?
>>>>> ---------------------------------------
>>>>>      flush_blks(f);
>>>>>
>>>>>      if (qemu_file_has_error(f)) {
>>>>>          blk_mig_cleanup(mon);
>>>>>          return 0;
>>>>>      }
>>>>>
>>>>>      blk_mig_reset_dirty_cursor();
>>>>> ----------------------------------------
>>>>>      if (stage == 2) {
>>>>>
>>>>>
>>>>>      another question is: since you event-tap io write(I think IO READ
>>>>> should also be event-tapped, as read may cause io chip state to
>>>>> change),  you then need not invoke qemu_savevm_state_full in
>>>>> qemu_savevm_trans_complete, right? thanks.
>>>>
>>>> It's not necessary to tap IO READ, but you can if you like.  We also have
>>>> experimental patches for this to reduce rams to be transfered.  But I
>>>> don't
>>>> understand why we don't have to invoke qemu_savevm_state_full although I
>>>> think we may reduce number of rams by replaying IO READ on the secondary.
>>>>
>>>
>>> I first think the objective of io-Write event-tap is to reproduce the
>>> same device state on the other side, though I doubt this,  so I think
>>> IO-Read also should be recorded and replayed. since event-tap is only
>>> to initial a ft transaction, the sync. of states still depend on
>>> qemu_save_vm_live/full,  I understand the design now, thanks.
>>>
>>> but I don't understand why io-write event-tap can reduce transfered
>>> rams as you mentioned, the amount of rams only depend on dirty pages,
>>> IO write don't change the normal process unlike block write, right?
>>
>> The point is, if we can assure that IO read retrieves the same data on both
>> sides, instead of dirtying the ram by read, meaning we have to transfer in
>> the transaction, just replay the operation and get the same data on the
>> otherside. Anyway, that's just a plan :)
>>
>> Thanks,
>>
>> Yoshi
>>
>>>
>>>> Thanks,
>>>>
>>>> Yoshi
>>>>
>>>>>
>>>>>
>>>>> Green.
>>>>>
>>>>>
>>>>>
>>>>> 2011/2/24 Yoshiaki Tamura<tamura.yoshiaki@lab.ntt.co.jp>:
>>>>>>
>>>>>> event-tap controls when to start FT transaction, and provides proxy
>>>>>> functions to called from net/block devices.  While FT transaction, it
>>>>>> queues up net/block requests, and flush them when the transaction gets
>>>>>> completed.
>>>>>>
>>>>>> Signed-off-by: Yoshiaki Tamura<tamura.yoshiaki@lab.ntt.co.jp>
>>>>>> Signed-off-by: OHMURA Kei<ohmura.kei@lab.ntt.co.jp>
>>>>>> ---
>>>>>>   Makefile.target |    1 +
>>>>>>   event-tap.c     |  940
>>>>>> +++++++++++++++++++++++++++++++++++++++++++++++++++++++
>>>>>>   event-tap.h     |   44 +++
>>>>>>   qemu-tool.c     |   28 ++
>>>>>>   trace-events    |   10 +
>>>>>>   5 files changed, 1023 insertions(+), 0 deletions(-)
>>>>>>   create mode 100644 event-tap.c
>>>>>>   create mode 100644 event-tap.h
>>>>>>
>>>>>> diff --git a/Makefile.target b/Makefile.target
>>>>>> index 220589e..da57efe 100644
>>>>>> --- a/Makefile.target
>>>>>> +++ b/Makefile.target
>>>>>> @@ -199,6 +199,7 @@ obj-y += rwhandler.o
>>>>>>   obj-$(CONFIG_KVM) += kvm.o kvm-all.o
>>>>>>   obj-$(CONFIG_NO_KVM) += kvm-stub.o
>>>>>>   LIBS+=-lz
>>>>>> +obj-y += event-tap.o
>>>>>>
>>>>>>   QEMU_CFLAGS += $(VNC_TLS_CFLAGS)
>>>>>>   QEMU_CFLAGS += $(VNC_SASL_CFLAGS)
>>>>>> diff --git a/event-tap.c b/event-tap.c
>>>>>> new file mode 100644
>>>>>> index 0000000..95c147a
>>>>>> --- /dev/null
>>>>>> +++ b/event-tap.c
>>>>>> @@ -0,0 +1,940 @@
>>>>>> +/*
>>>>>> + * Event Tap functions for QEMU
>>>>>> + *
>>>>>> + * Copyright (c) 2010 Nippon Telegraph and Telephone Corporation.
>>>>>> + *
>>>>>> + * This work is licensed under the terms of the GNU GPL, version 2.
>>>>>>   See
>>>>>> + * the COPYING file in the top-level directory.
>>>>>> + */
>>>>>> +
>>>>>> +#include "qemu-common.h"
>>>>>> +#include "qemu-error.h"
>>>>>> +#include "block.h"
>>>>>> +#include "block_int.h"
>>>>>> +#include "ioport.h"
>>>>>> +#include "osdep.h"
>>>>>> +#include "sysemu.h"
>>>>>> +#include "hw/hw.h"
>>>>>> +#include "net.h"
>>>>>> +#include "event-tap.h"
>>>>>> +#include "trace.h"
>>>>>> +
>>>>>> +enum EVENT_TAP_STATE {
>>>>>> +    EVENT_TAP_OFF,
>>>>>> +    EVENT_TAP_ON,
>>>>>> +    EVENT_TAP_SUSPEND,
>>>>>> +    EVENT_TAP_FLUSH,
>>>>>> +    EVENT_TAP_LOAD,
>>>>>> +    EVENT_TAP_REPLAY,
>>>>>> +};
>>>>>> +
>>>>>> +static enum EVENT_TAP_STATE event_tap_state = EVENT_TAP_OFF;
>>>>>> +
>>>>>> +typedef struct EventTapIOport {
>>>>>> +    uint32_t address;
>>>>>> +    uint32_t data;
>>>>>> +    int      index;
>>>>>> +} EventTapIOport;
>>>>>> +
>>>>>> +#define MMIO_BUF_SIZE 8
>>>>>> +
>>>>>> +typedef struct EventTapMMIO {
>>>>>> +    uint64_t address;
>>>>>> +    uint8_t  buf[MMIO_BUF_SIZE];
>>>>>> +    int      len;
>>>>>> +} EventTapMMIO;
>>>>>> +
>>>>>> +typedef struct EventTapNetReq {
>>>>>> +    char *device_name;
>>>>>> +    int iovcnt;
>>>>>> +    int vlan_id;
>>>>>> +    bool vlan_needed;
>>>>>> +    bool async;
>>>>>> +    struct iovec *iov;
>>>>>> +    NetPacketSent *sent_cb;
>>>>>> +} EventTapNetReq;
>>>>>> +
>>>>>> +#define MAX_BLOCK_REQUEST 32
>>>>>> +
>>>>>> +typedef struct EventTapAIOCB EventTapAIOCB;
>>>>>> +
>>>>>> +typedef struct EventTapBlkReq {
>>>>>> +    char *device_name;
>>>>>> +    int num_reqs;
>>>>>> +    int num_cbs;
>>>>>> +    bool is_flush;
>>>>>> +    BlockRequest reqs[MAX_BLOCK_REQUEST];
>>>>>> +    EventTapAIOCB *acb[MAX_BLOCK_REQUEST];
>>>>>> +} EventTapBlkReq;
>>>>>> +
>>>>>> +#define EVENT_TAP_IOPORT (1<<      0)
>>>>>> +#define EVENT_TAP_MMIO   (1<<      1)
>>>>>> +#define EVENT_TAP_NET    (1<<      2)
>>>>>> +#define EVENT_TAP_BLK    (1<<      3)
>>>>>> +
>>>>>> +#define EVENT_TAP_TYPE_MASK (EVENT_TAP_NET - 1)
>>>>>> +
>>>>>> +typedef struct EventTapLog {
>>>>>> +    int mode;
>>>>>> +    union {
>>>>>> +        EventTapIOport ioport;
>>>>>> +        EventTapMMIO mmio;
>>>>>> +    };
>>>>>> +    union {
>>>>>> +        EventTapNetReq net_req;
>>>>>> +        EventTapBlkReq blk_req;
>>>>>> +    };
>>>>>> +    QTAILQ_ENTRY(EventTapLog) node;
>>>>>> +} EventTapLog;
>>>>>> +
>>>>>> +struct EventTapAIOCB {
>>>>>> +    BlockDriverAIOCB common;
>>>>>> +    BlockDriverAIOCB *acb;
>>>>>> +    bool is_canceled;
>>>>>> +};
>>>>>> +
>>>>>> +static EventTapLog *last_event_tap;
>>>>>> +
>>>>>> +static QTAILQ_HEAD(, EventTapLog) event_list;
>>>>>> +static QTAILQ_HEAD(, EventTapLog) event_pool;
>>>>>> +
>>>>>> +static int (*event_tap_cb)(void);
>>>>>> +static QEMUBH *event_tap_bh;
>>>>>> +static VMChangeStateEntry *vmstate;
>>>>>> +
>>>>>> +static void event_tap_bh_cb(void *p)
>>>>>> +{
>>>>>> +    if (event_tap_cb) {
>>>>>> +        event_tap_cb();
>>>>>> +    }
>>>>>> +
>>>>>> +    qemu_bh_delete(event_tap_bh);
>>>>>> +    event_tap_bh = NULL;
>>>>>> +}
>>>>>> +
>>>>>> +static void event_tap_schedule_bh(void)
>>>>>> +{
>>>>>> +    trace_event_tap_ignore_bh(!!event_tap_bh);
>>>>>> +
>>>>>> +    /* if bh is already set, we ignore it for now */
>>>>>> +    if (event_tap_bh) {
>>>>>> +        return;
>>>>>> +    }
>>>>>> +
>>>>>> +    event_tap_bh = qemu_bh_new(event_tap_bh_cb, NULL);
>>>>>> +    qemu_bh_schedule(event_tap_bh);
>>>>>> +
>>>>>> +    return;
>>>>>> +}
>>>>>> +
>>>>>> +static void *event_tap_alloc_log(void)
>>>>>> +{
>>>>>> +    EventTapLog *log;
>>>>>> +
>>>>>> +    if (QTAILQ_EMPTY(&event_pool)) {
>>>>>> +        log = qemu_mallocz(sizeof(EventTapLog));
>>>>>> +    } else {
>>>>>> +        log = QTAILQ_FIRST(&event_pool);
>>>>>> +        QTAILQ_REMOVE(&event_pool, log, node);
>>>>>> +    }
>>>>>> +
>>>>>> +    return log;
>>>>>> +}
>>>>>> +
>>>>>> +static void event_tap_free_net_req(EventTapNetReq *net_req);
>>>>>> +static void event_tap_free_blk_req(EventTapBlkReq *blk_req);
>>>>>> +
>>>>>> +static void event_tap_free_log(EventTapLog *log)
>>>>>> +{
>>>>>> +    int mode = log->mode&      ~EVENT_TAP_TYPE_MASK;
>>>>>> +
>>>>>> +    if (mode == EVENT_TAP_NET) {
>>>>>> +        event_tap_free_net_req(&log->net_req);
>>>>>> +    } else if (mode == EVENT_TAP_BLK) {
>>>>>> +        event_tap_free_blk_req(&log->blk_req);
>>>>>> +    }
>>>>>> +
>>>>>> +    log->mode = 0;
>>>>>> +
>>>>>> +    /* return the log to event_pool */
>>>>>> +    QTAILQ_INSERT_HEAD(&event_pool, log, node);
>>>>>> +}
>>>>>> +
>>>>>> +static void event_tap_free_pool(void)
>>>>>> +{
>>>>>> +    EventTapLog *log, *next;
>>>>>> +
>>>>>> +    QTAILQ_FOREACH_SAFE(log,&event_pool, node, next) {
>>>>>> +        QTAILQ_REMOVE(&event_pool, log, node);
>>>>>> +        qemu_free(log);
>>>>>> +    }
>>>>>> +}
>>>>>> +
>>>>>> +static void event_tap_free_net_req(EventTapNetReq *net_req)
>>>>>> +{
>>>>>> +    int i;
>>>>>> +
>>>>>> +    if (!net_req->async) {
>>>>>> +        for (i = 0; i<      net_req->iovcnt; i++) {
>>>>>> +            qemu_free(net_req->iov[i].iov_base);
>>>>>> +        }
>>>>>> +        qemu_free(net_req->iov);
>>>>>> +    } else if (event_tap_state>= EVENT_TAP_LOAD) {
>>>>>> +        qemu_free(net_req->iov);
>>>>>> +    }
>>>>>> +
>>>>>> +    qemu_free(net_req->device_name);
>>>>>> +}
>>>>>> +
>>>>>> +static void event_tap_alloc_net_req(EventTapNetReq *net_req,
>>>>>> +                                   VLANClientState *vc,
>>>>>> +                                   const struct iovec *iov, int
>>>>>> iovcnt,
>>>>>> +                                   NetPacketSent *sent_cb, bool async)
>>>>>> +{
>>>>>> +    int i;
>>>>>> +
>>>>>> +    net_req->iovcnt = iovcnt;
>>>>>> +    net_req->async = async;
>>>>>> +    net_req->device_name = qemu_strdup(vc->name);
>>>>>> +    net_req->sent_cb = sent_cb;
>>>>>> +
>>>>>> +    if (vc->vlan) {
>>>>>> +        net_req->vlan_needed = 1;
>>>>>> +        net_req->vlan_id = vc->vlan->id;
>>>>>> +    } else {
>>>>>> +        net_req->vlan_needed = 0;
>>>>>> +    }
>>>>>> +
>>>>>> +    if (async) {
>>>>>> +        net_req->iov = (struct iovec *)iov;
>>>>>> +    } else {
>>>>>> +        net_req->iov = qemu_malloc(sizeof(struct iovec) * iovcnt);
>>>>>> +        for (i = 0; i<      iovcnt; i++) {
>>>>>> +            net_req->iov[i].iov_base = qemu_malloc(iov[i].iov_len);
>>>>>> +            memcpy(net_req->iov[i].iov_base, iov[i].iov_base,
>>>>>> iov[i].iov_len);
>>>>>> +            net_req->iov[i].iov_len = iov[i].iov_len;
>>>>>> +        }
>>>>>> +    }
>>>>>> +}
>>>>>> +
>>>>>> +static void event_tap_packet(VLANClientState *vc, const struct iovec
>>>>>> *iov,
>>>>>> +                            int iovcnt, NetPacketSent *sent_cb, bool
>>>>>> async)
>>>>>> +{
>>>>>> +    int empty;
>>>>>> +    EventTapLog *log = last_event_tap;
>>>>>> +
>>>>>> +    if (!log) {
>>>>>> +        trace_event_tap_no_event();
>>>>>> +        log = event_tap_alloc_log();
>>>>>> +    }
>>>>>> +
>>>>>> +    if (log->mode&      ~EVENT_TAP_TYPE_MASK) {
>>>>>> +        trace_event_tap_already_used(log->mode&
>>>>>>   ~EVENT_TAP_TYPE_MASK);
>>>>>> +        return;
>>>>>> +    }
>>>>>> +
>>>>>> +    log->mode |= EVENT_TAP_NET;
>>>>>> +    event_tap_alloc_net_req(&log->net_req, vc, iov, iovcnt, sent_cb,
>>>>>> async);
>>>>>> +
>>>>>> +    empty = QTAILQ_EMPTY(&event_list);
>>>>>> +    QTAILQ_INSERT_TAIL(&event_list, log, node);
>>>>>> +    last_event_tap = NULL;
>>>>>> +
>>>>>> +    if (empty) {
>>>>>> +        event_tap_schedule_bh();
>>>>>> +    }
>>>>>> +}
>>>>>> +
>>>>>> +void event_tap_send_packet(VLANClientState *vc, const uint8_t *buf,
>>>>>> int
>>>>>> size)
>>>>>> +{
>>>>>> +    struct iovec iov;
>>>>>> +
>>>>>> +    assert(event_tap_state == EVENT_TAP_ON);
>>>>>> +
>>>>>> +    iov.iov_base = (uint8_t *)buf;
>>>>>> +    iov.iov_len = size;
>>>>>> +    event_tap_packet(vc,&iov, 1, NULL, 0);
>>>>>> +
>>>>>> +    return;
>>>>>> +}
>>>>>> +
>>>>>> +ssize_t event_tap_sendv_packet_async(VLANClientState *vc,
>>>>>> +                                     const struct iovec *iov,
>>>>>> +                                     int iovcnt, NetPacketSent
>>>>>> *sent_cb)
>>>>>> +{
>>>>>> +    assert(event_tap_state == EVENT_TAP_ON);
>>>>>> +    event_tap_packet(vc, iov, iovcnt, sent_cb, 1);
>>>>>> +    return 0;
>>>>>> +}
>>>>>> +
>>>>>> +static void event_tap_net_flush(EventTapNetReq *net_req)
>>>>>> +{
>>>>>> +    VLANClientState *vc;
>>>>>> +    ssize_t len;
>>>>>> +
>>>>>> +    if (net_req->vlan_needed) {
>>>>>> +        vc = qemu_find_vlan_client_by_name(NULL, net_req->vlan_id,
>>>>>> +                                           net_req->device_name);
>>>>>> +    } else {
>>>>>> +        vc = qemu_find_netdev(net_req->device_name);
>>>>>> +    }
>>>>>> +
>>>>>> +    if (net_req->async) {
>>>>>> +        len = qemu_sendv_packet_async(vc, net_req->iov,
>>>>>> net_req->iovcnt,
>>>>>> +                                      net_req->sent_cb);
>>>>>> +        if (len) {
>>>>>> +            net_req->sent_cb(vc, len);
>>>>>> +        } else {
>>>>>> +            /* packets are queued in the net layer */
>>>>>> +            trace_event_tap_append_packet();
>>>>>> +        }
>>>>>> +    } else {
>>>>>> +        qemu_send_packet(vc, net_req->iov[0].iov_base,
>>>>>> +                         net_req->iov[0].iov_len);
>>>>>> +    }
>>>>>> +
>>>>>> +    /* force flush to avoid request inversion */
>>>>>> +    qemu_aio_flush();
>>>>>> +}
>>>>>> +
>>>>>> +static void event_tap_net_save(QEMUFile *f, EventTapNetReq *net_req)
>>>>>> +{
>>>>>> +    ram_addr_t page_addr;
>>>>>> +    int i, len;
>>>>>> +
>>>>>> +    len = strlen(net_req->device_name);
>>>>>> +    qemu_put_byte(f, len);
>>>>>> +    qemu_put_buffer(f, (uint8_t *)net_req->device_name, len);
>>>>>> +    qemu_put_byte(f, net_req->vlan_id);
>>>>>> +    qemu_put_byte(f, net_req->vlan_needed);
>>>>>> +    qemu_put_byte(f, net_req->async);
>>>>>> +    qemu_put_be32(f, net_req->iovcnt);
>>>>>> +
>>>>>> +    for (i = 0; i<      net_req->iovcnt; i++) {
>>>>>> +        qemu_put_be64(f, net_req->iov[i].iov_len);
>>>>>> +        if (net_req->async) {
>>>>>> +            page_addr =
>>>>>> +
>>>>>>   qemu_ram_addr_from_host_nofail(net_req->iov[i].iov_base);
>>>>>> +            qemu_put_be64(f, page_addr);
>>>>>> +        } else {
>>>>>> +            qemu_put_buffer(f, (uint8_t *)net_req->iov[i].iov_base,
>>>>>> +                            net_req->iov[i].iov_len);
>>>>>> +        }
>>>>>> +    }
>>>>>> +}
>>>>>> +
>>>>>> +static void event_tap_net_load(QEMUFile *f, EventTapNetReq *net_req)
>>>>>> +{
>>>>>> +    ram_addr_t page_addr;
>>>>>> +    int i, len;
>>>>>> +
>>>>>> +    len = qemu_get_byte(f);
>>>>>> +    net_req->device_name = qemu_malloc(len + 1);
>>>>>> +    qemu_get_buffer(f, (uint8_t *)net_req->device_name, len);
>>>>>> +    net_req->device_name[len] = '\0';
>>>>>> +    net_req->vlan_id = qemu_get_byte(f);
>>>>>> +    net_req->vlan_needed = qemu_get_byte(f);
>>>>>> +    net_req->async = qemu_get_byte(f);
>>>>>> +    net_req->iovcnt = qemu_get_be32(f);
>>>>>> +    net_req->iov = qemu_malloc(sizeof(struct iovec) *
>>>>>> net_req->iovcnt);
>>>>>> +
>>>>>> +    for (i = 0; i<      net_req->iovcnt; i++) {
>>>>>> +        net_req->iov[i].iov_len = qemu_get_be64(f);
>>>>>> +        if (net_req->async) {
>>>>>> +            page_addr = qemu_get_be64(f);
>>>>>> +            net_req->iov[i].iov_base = qemu_get_ram_ptr(page_addr);
>>>>>> +        } else {
>>>>>> +            net_req->iov[i].iov_base =
>>>>>> qemu_malloc(net_req->iov[i].iov_len);
>>>>>> +            qemu_get_buffer(f, (uint8_t *)net_req->iov[i].iov_base,
>>>>>> +                            net_req->iov[i].iov_len);
>>>>>> +        }
>>>>>> +    }
>>>>>> +}
>>>>>> +
>>>>>> +static void event_tap_free_blk_req(EventTapBlkReq *blk_req)
>>>>>> +{
>>>>>> +    int i;
>>>>>> +
>>>>>> +    if (event_tap_state>= EVENT_TAP_LOAD&&      !blk_req->is_flush) {
>>>>>> +        for (i = 0; i<      blk_req->num_reqs; i++) {
>>>>>> +            qemu_iovec_destroy(blk_req->reqs[i].qiov);
>>>>>> +            qemu_free(blk_req->reqs[i].qiov);
>>>>>> +        }
>>>>>> +    }
>>>>>> +
>>>>>> +    qemu_free(blk_req->device_name);
>>>>>> +}
>>>>>> +
>>>>>> +static void event_tap_blk_cb(void *opaque, int ret)
>>>>>> +{
>>>>>> +    EventTapLog *log = container_of(opaque, EventTapLog, blk_req);
>>>>>> +    EventTapBlkReq *blk_req = opaque;
>>>>>> +    int i;
>>>>>> +
>>>>>> +    blk_req->num_cbs--;
>>>>>> +
>>>>>> +    /* all outstanding requests are flushed */
>>>>>> +    if (blk_req->num_cbs == 0) {
>>>>>> +        for (i = 0; i<      blk_req->num_reqs; i++) {
>>>>>> +            EventTapAIOCB *eacb = blk_req->acb[i];
>>>>>> +            eacb->common.cb(eacb->common.opaque, ret);
>>>>>> +            qemu_aio_release(eacb);
>>>>>> +        }
>>>>>> +
>>>>>> +        event_tap_free_log(log);
>>>>>> +    }
>>>>>> +}
>>>>>> +
>>>>>> +static void event_tap_bdrv_aio_cancel(BlockDriverAIOCB *acb)
>>>>>> +{
>>>>>> +    EventTapAIOCB *eacb = container_of(acb, EventTapAIOCB, common);
>>>>>> +
>>>>>> +    /* check if already passed to block layer */
>>>>>> +    if (eacb->acb) {
>>>>>> +        bdrv_aio_cancel(eacb->acb);
>>>>>> +    } else {
>>>>>> +        eacb->is_canceled = 1;
>>>>>> +    }
>>>>>> +}
>>>>>> +
>>>>>> +static AIOPool event_tap_aio_pool = {
>>>>>> +    .aiocb_size = sizeof(EventTapAIOCB),
>>>>>> +    .cancel     = event_tap_bdrv_aio_cancel,
>>>>>> +};
>>>>>> +
>>>>>> +static void event_tap_alloc_blk_req(EventTapBlkReq *blk_req,
>>>>>> +                                    BlockDriverState *bs, BlockRequest
>>>>>> *reqs,
>>>>>> +                                    int num_reqs, void *opaque, bool
>>>>>> is_flush)
>>>>>> +{
>>>>>> +    int i;
>>>>>> +
>>>>>> +    blk_req->num_reqs = num_reqs;
>>>>>> +    blk_req->num_cbs = num_reqs;
>>>>>> +    blk_req->device_name = qemu_strdup(bs->device_name);
>>>>>> +    blk_req->is_flush = is_flush;
>>>>>> +
>>>>>> +    for (i = 0; i<      num_reqs; i++) {
>>>>>> +        blk_req->reqs[i].sector = reqs[i].sector;
>>>>>> +        blk_req->reqs[i].nb_sectors = reqs[i].nb_sectors;
>>>>>> +        blk_req->reqs[i].qiov = reqs[i].qiov;
>>>>>> +        blk_req->reqs[i].cb = event_tap_blk_cb;
>>>>>> +        blk_req->reqs[i].opaque = opaque;
>>>>>> +
>>>>>> +        blk_req->acb[i] = qemu_aio_get(&event_tap_aio_pool, bs,
>>>>>> +                                       reqs[i].cb, reqs[i].opaque);
>>>>>> +    }
>>>>>> +}
>>>>>> +
>>>>>> +static EventTapBlkReq *event_tap_bdrv(BlockDriverState *bs,
>>>>>> BlockRequest
>>>>>> *reqs,
>>>>>> +                                      int num_reqs, bool is_flush)
>>>>>> +{
>>>>>> +    EventTapLog *log = last_event_tap;
>>>>>> +    int empty;
>>>>>> +
>>>>>> +    if (!log) {
>>>>>> +        trace_event_tap_no_event();
>>>>>> +        log = event_tap_alloc_log();
>>>>>> +    }
>>>>>> +
>>>>>> +    if (log->mode&      ~EVENT_TAP_TYPE_MASK) {
>>>>>> +        trace_event_tap_already_used(log->mode&
>>>>>>   ~EVENT_TAP_TYPE_MASK);
>>>>>> +        return NULL;
>>>>>> +    }
>>>>>> +
>>>>>> +    log->mode |= EVENT_TAP_BLK;
>>>>>> +    event_tap_alloc_blk_req(&log->blk_req, bs, reqs,
>>>>>> +                            num_reqs,&log->blk_req, is_flush);
>>>>>> +
>>>>>> +    empty = QTAILQ_EMPTY(&event_list);
>>>>>> +    QTAILQ_INSERT_TAIL(&event_list, log, node);
>>>>>> +    last_event_tap = NULL;
>>>>>> +
>>>>>> +    if (empty) {
>>>>>> +        event_tap_schedule_bh();
>>>>>> +    }
>>>>>> +
>>>>>> +    return&log->blk_req;
>>>>>> +}
>>>>>> +
>>>>>> +BlockDriverAIOCB *event_tap_bdrv_aio_writev(BlockDriverState *bs,
>>>>>> +                                            int64_t sector_num,
>>>>>> +                                            QEMUIOVector *iov,
>>>>>> +                                            int nb_sectors,
>>>>>> +                                            BlockDriverCompletionFunc
>>>>>> *cb,
>>>>>> +                                            void *opaque)
>>>>>> +{
>>>>>> +    BlockRequest req;
>>>>>> +    EventTapBlkReq *ereq;
>>>>>> +
>>>>>> +    assert(event_tap_state == EVENT_TAP_ON);
>>>>>> +
>>>>>> +    req.sector = sector_num;
>>>>>> +    req.nb_sectors = nb_sectors;
>>>>>> +    req.qiov = iov;
>>>>>> +    req.cb = cb;
>>>>>> +    req.opaque = opaque;
>>>>>> +    ereq = event_tap_bdrv(bs,&req, 1, 0);
>>>>>> +
>>>>>> +    return&ereq->acb[0]->common;
>>>>>> +}
>>>>>> +
>>>>>> +BlockDriverAIOCB *event_tap_bdrv_aio_flush(BlockDriverState *bs,
>>>>>> +                                           BlockDriverCompletionFunc
>>>>>> *cb,
>>>>>> +                                           void *opaque)
>>>>>> +{
>>>>>> +    BlockRequest req;
>>>>>> +    EventTapBlkReq *ereq;
>>>>>> +
>>>>>> +    assert(event_tap_state == EVENT_TAP_ON);
>>>>>> +
>>>>>> +    memset(&req, 0, sizeof(req));
>>>>>> +    req.cb = cb;
>>>>>> +    req.opaque = opaque;
>>>>>> +    ereq = event_tap_bdrv(bs,&req, 1, 1);
>>>>>> +
>>>>>> +    return&ereq->acb[0]->common;
>>>>>> +}
>>>>>> +
>>>>>> +void event_tap_bdrv_flush(void)
>>>>>> +{
>>>>>> +    qemu_bh_cancel(event_tap_bh);
>>>>>> +
>>>>>> +    while (!QTAILQ_EMPTY(&event_list)) {
>>>>>> +        event_tap_cb();
>>>>>> +    }
>>>>>> +}
>>>>>> +
>>>>>> +static void event_tap_blk_flush(EventTapBlkReq *blk_req)
>>>>>> +{
>>>>>> +    int i, ret;
>>>>>> +
>>>>>> +    for (i = 0; i<      blk_req->num_reqs; i++) {
>>>>>> +        BlockRequest *req =&blk_req->reqs[i];
>>>>>> +        EventTapAIOCB *eacb = blk_req->acb[i];
>>>>>> +        BlockDriverAIOCB *acb =&eacb->common;
>>>>>> +
>>>>>> +        /* don't flush if canceled */
>>>>>> +        if (eacb->is_canceled) {
>>>>>> +            continue;
>>>>>> +        }
>>>>>> +
>>>>>> +        /* receiver needs to restore bs from device name */
>>>>>> +        if (!acb->bs) {
>>>>>> +            acb->bs = bdrv_find(blk_req->device_name);
>>>>>> +        }
>>>>>> +
>>>>>> +        if (blk_req->is_flush) {
>>>>>> +            eacb->acb = bdrv_aio_flush(acb->bs, req->cb, req->opaque);
>>>>>> +            if (!eacb->acb) {
>>>>>> +                req->cb(req->opaque, -EIO);
>>>>>> +            }
>>>>>> +            return;
>>>>>> +        }
>>>>>> +
>>>>>> +        eacb->acb = bdrv_aio_writev(acb->bs, req->sector, req->qiov,
>>>>>> +                                    req->nb_sectors, req->cb,
>>>>>> req->opaque);
>>>>>> +        if (!eacb->acb) {
>>>>>> +            req->cb(req->opaque, -EIO);
>>>>>> +        }
>>>>>> +
>>>>>> +        /* force flush to avoid request inversion */
>>>>>> +        qemu_aio_flush();
>>>>>> +        ret = bdrv_flush(acb->bs);
>>>>>> +        if (ret<      0) {
>>>>>> +            error_report("flushing blk_req to %s failed",
>>>>>> blk_req->device_name);
>>>>>> +        }
>>>>>> +    }
>>>>>> +}
>>>>>> +
>>>>>> +static void event_tap_blk_save(QEMUFile *f, EventTapBlkReq *blk_req)
>>>>>> +{
>>>>>> +    ram_addr_t page_addr;
>>>>>> +    int i, j, len;
>>>>>> +
>>>>>> +    len = strlen(blk_req->device_name);
>>>>>> +    qemu_put_byte(f, len);
>>>>>> +    qemu_put_buffer(f, (uint8_t *)blk_req->device_name, len);
>>>>>> +    qemu_put_byte(f, blk_req->num_reqs);
>>>>>> +    qemu_put_byte(f, blk_req->is_flush);
>>>>>> +
>>>>>> +    if (blk_req->is_flush) {
>>>>>> +        return;
>>>>>> +    }
>>>>>> +
>>>>>> +    for (i = 0; i<      blk_req->num_reqs; i++) {
>>>>>> +        BlockRequest *req =&blk_req->reqs[i];
>>>>>> +        EventTapAIOCB *eacb = blk_req->acb[i];
>>>>>> +        /* don't save canceled requests */
>>>>>> +        if (eacb->is_canceled) {
>>>>>> +            continue;
>>>>>> +        }
>>>>>> +        qemu_put_be64(f, req->sector);
>>>>>> +        qemu_put_be32(f, req->nb_sectors);
>>>>>> +        qemu_put_be32(f, req->qiov->niov);
>>>>>> +
>>>>>> +        for (j = 0; j<      req->qiov->niov; j++) {
>>>>>> +            page_addr =
>>>>>> +
>>>>>>   qemu_ram_addr_from_host_nofail(req->qiov->iov[j].iov_base);
>>>>>> +            qemu_put_be64(f, page_addr);
>>>>>> +            qemu_put_be64(f, req->qiov->iov[j].iov_len);
>>>>>> +        }
>>>>>> +    }
>>>>>> +}
>>>>>> +
>>>>>> +static void event_tap_blk_load(QEMUFile *f, EventTapBlkReq *blk_req)
>>>>>> +{
>>>>>> +    BlockRequest *req;
>>>>>> +    ram_addr_t page_addr;
>>>>>> +    int i, j, len, niov;
>>>>>> +
>>>>>> +    len = qemu_get_byte(f);
>>>>>> +    blk_req->device_name = qemu_malloc(len + 1);
>>>>>> +    qemu_get_buffer(f, (uint8_t *)blk_req->device_name, len);
>>>>>> +    blk_req->device_name[len] = '\0';
>>>>>> +    blk_req->num_reqs = qemu_get_byte(f);
>>>>>> +    blk_req->is_flush = qemu_get_byte(f);
>>>>>> +
>>>>>> +    if (blk_req->is_flush) {
>>>>>> +        return;
>>>>>> +    }
>>>>>> +
>>>>>> +    for (i = 0; i<      blk_req->num_reqs; i++) {
>>>>>> +        req =&blk_req->reqs[i];
>>>>>> +        req->sector = qemu_get_be64(f);
>>>>>> +        req->nb_sectors = qemu_get_be32(f);
>>>>>> +        req->qiov = qemu_mallocz(sizeof(QEMUIOVector));
>>>>>> +        niov = qemu_get_be32(f);
>>>>>> +        qemu_iovec_init(req->qiov, niov);
>>>>>> +
>>>>>> +        for (j = 0; j<      niov; j++) {
>>>>>> +            void *iov_base;
>>>>>> +            size_t iov_len;
>>>>>> +            page_addr = qemu_get_be64(f);
>>>>>> +            iov_base = qemu_get_ram_ptr(page_addr);
>>>>>> +            iov_len = qemu_get_be64(f);
>>>>>> +            qemu_iovec_add(req->qiov, iov_base, iov_len);
>>>>>> +        }
>>>>>> +    }
>>>>>> +}
>>>>>> +
>>>>>> +void event_tap_ioport(int index, uint32_t address, uint32_t data)
>>>>>> +{
>>>>>> +    if (event_tap_state != EVENT_TAP_ON) {
>>>>>> +        return;
>>>>>> +    }
>>>>>> +
>>>>>> +    if (!last_event_tap) {
>>>>>> +        last_event_tap = event_tap_alloc_log();
>>>>>> +    }
>>>>>> +
>>>>>> +    last_event_tap->mode = EVENT_TAP_IOPORT;
>>>>>> +    last_event_tap->ioport.index = index;
>>>>>> +    last_event_tap->ioport.address = address;
>>>>>> +    last_event_tap->ioport.data = data;
>>>>>> +}
>>>>>> +
>>>>>> +static inline void event_tap_ioport_save(QEMUFile *f, EventTapIOport
>>>>>> *ioport)
>>>>>> +{
>>>>>> +    qemu_put_be32(f, ioport->index);
>>>>>> +    qemu_put_be32(f, ioport->address);
>>>>>> +    qemu_put_byte(f, ioport->data);
>>>>>> +}
>>>>>> +
>>>>>> +static inline void event_tap_ioport_load(QEMUFile *f,
>>>>>> +                                         EventTapIOport *ioport)
>>>>>> +{
>>>>>> +    ioport->index = qemu_get_be32(f);
>>>>>> +    ioport->address = qemu_get_be32(f);
>>>>>> +    ioport->data = qemu_get_byte(f);
>>>>>> +}
>>>>>> +
>>>>>> +void event_tap_mmio(uint64_t address, uint8_t *buf, int len)
>>>>>> +{
>>>>>> +    if (event_tap_state != EVENT_TAP_ON || len>      MMIO_BUF_SIZE) {
>>>>>> +        return;
>>>>>> +    }
>>>>>> +
>>>>>> +    if (!last_event_tap) {
>>>>>> +        last_event_tap = event_tap_alloc_log();
>>>>>> +    }
>>>>>> +
>>>>>> +    last_event_tap->mode = EVENT_TAP_MMIO;
>>>>>> +    last_event_tap->mmio.address = address;
>>>>>> +    last_event_tap->mmio.len = len;
>>>>>> +    memcpy(last_event_tap->mmio.buf, buf, len);
>>>>>> +}
>>>>>> +
>>>>>> +static inline void event_tap_mmio_save(QEMUFile *f, EventTapMMIO
>>>>>> *mmio)
>>>>>> +{
>>>>>> +    qemu_put_be64(f, mmio->address);
>>>>>> +    qemu_put_byte(f, mmio->len);
>>>>>> +    qemu_put_buffer(f, mmio->buf, mmio->len);
>>>>>> +}
>>>>>> +
>>>>>> +static inline void event_tap_mmio_load(QEMUFile *f, EventTapMMIO
>>>>>> *mmio)
>>>>>> +{
>>>>>> +    mmio->address = qemu_get_be64(f);
>>>>>> +    mmio->len = qemu_get_byte(f);
>>>>>> +    qemu_get_buffer(f, mmio->buf, mmio->len);
>>>>>> +}
>>>>>> +
>>>>>> +int event_tap_register(int (*cb)(void))
>>>>>> +{
>>>>>> +    if (event_tap_state != EVENT_TAP_OFF) {
>>>>>> +        error_report("event-tap is already on");
>>>>>> +        return -EINVAL;
>>>>>> +    }
>>>>>> +
>>>>>> +    if (!cb || event_tap_cb) {
>>>>>> +        error_report("can't set event_tap_cb");
>>>>>> +        return -EINVAL;
>>>>>> +    }
>>>>>> +
>>>>>> +    event_tap_cb = cb;
>>>>>> +    event_tap_state = EVENT_TAP_ON;
>>>>>> +
>>>>>> +    return 0;
>>>>>> +}
>>>>>> +
>>>>>> +void event_tap_unregister(void)
>>>>>> +{
>>>>>> +    if (event_tap_state == EVENT_TAP_OFF) {
>>>>>> +        error_report("event-tap is already off");
>>>>>> +        return;
>>>>>> +    }
>>>>>> +
>>>>>> +    qemu_del_vm_change_state_handler(vmstate);
>>>>>> +
>>>>>> +    event_tap_flush();
>>>>>> +    event_tap_free_pool();
>>>>>> +
>>>>>> +    event_tap_state = EVENT_TAP_OFF;
>>>>>> +    event_tap_cb = NULL;
>>>>>> +}
>>>>>> +
>>>>>> +int event_tap_is_on(void)
>>>>>> +{
>>>>>> +    return (event_tap_state == EVENT_TAP_ON);
>>>>>> +}
>>>>>> +
>>>>>> +static void event_tap_suspend(void *opaque, int running, int reason)
>>>>>> +{
>>>>>> +    event_tap_state = running ? EVENT_TAP_ON : EVENT_TAP_SUSPEND;
>>>>>> +}
>>>>>> +
>>>>>> +/* returns 1 if the queue gets emtpy */
>>>>>> +int event_tap_flush_one(void)
>>>>>> +{
>>>>>> +    EventTapLog *log;
>>>>>> +    int ret;
>>>>>> +
>>>>>> +    if (QTAILQ_EMPTY(&event_list)) {
>>>>>> +        return 1;
>>>>>> +    }
>>>>>> +
>>>>>> +    event_tap_state = EVENT_TAP_FLUSH;
>>>>>> +
>>>>>> +    log = QTAILQ_FIRST(&event_list);
>>>>>> +    QTAILQ_REMOVE(&event_list, log, node);
>>>>>> +    switch (log->mode&      ~EVENT_TAP_TYPE_MASK) {
>>>>>> +    case EVENT_TAP_NET:
>>>>>> +        event_tap_net_flush(&log->net_req);
>>>>>> +        event_tap_free_log(log);
>>>>>> +        break;
>>>>>> +    case EVENT_TAP_BLK:
>>>>>> +        event_tap_blk_flush(&log->blk_req);
>>>>>> +        break;
>>>>>> +    default:
>>>>>> +        error_report("Unknown state %d", log->mode);
>>>>>> +        event_tap_free_log(log);
>>>>>> +        return -EINVAL;
>>>>>> +    }
>>>>>> +
>>>>>> +    ret = QTAILQ_EMPTY(&event_list);
>>>>>> +    event_tap_state = ret ? EVENT_TAP_ON : EVENT_TAP_FLUSH;
>>>>>> +
>>>>>> +    return ret;
>>>>>> +}
>>>>>> +
>>>>>> +void event_tap_flush(void)
>>>>>> +{
>>>>>> +    int ret;
>>>>>> +
>>>>>> +    do {
>>>>>> +        ret = event_tap_flush_one();
>>>>>> +    } while (ret == 0);
>>>>>> +
>>>>>> +    if (ret<      0) {
>>>>>> +        error_report("error flushing event-tap requests");
>>>>>> +        abort();
>>>>>> +    }
>>>>>> +}
>>>>>> +
>>>>>> +static void event_tap_replay(void *opaque, int running, int reason)
>>>>>> +{
>>>>>> +    EventTapLog *log, *next;
>>>>>> +
>>>>>> +    if (!running) {
>>>>>> +        return;
>>>>>> +    }
>>>>>> +
>>>>>> +    assert(event_tap_state == EVENT_TAP_LOAD);
>>>>>> +
>>>>>> +    event_tap_state = EVENT_TAP_REPLAY;
>>>>>> +
>>>>>> +    QTAILQ_FOREACH(log,&event_list, node) {
>>>>>> +        if ((log->mode&      ~EVENT_TAP_TYPE_MASK) == EVENT_TAP_NET) {
>>>>>> +            EventTapNetReq *net_req =&log->net_req;
>>>>>> +            if (!net_req->async) {
>>>>>> +                event_tap_net_flush(net_req);
>>>>>> +                continue;
>>>>>> +            }
>>>>>> +        }
>>>>>> +
>>>>>> +        switch (log->mode&      EVENT_TAP_TYPE_MASK) {
>>>>>> +        case EVENT_TAP_IOPORT:
>>>>>> +            switch (log->ioport.index) {
>>>>>> +            case 0:
>>>>>> +                cpu_outb(log->ioport.address, log->ioport.data);
>>>>>> +                break;
>>>>>> +            case 1:
>>>>>> +                cpu_outw(log->ioport.address, log->ioport.data);
>>>>>> +                break;
>>>>>> +            case 2:
>>>>>> +                cpu_outl(log->ioport.address, log->ioport.data);
>>>>>> +                break;
>>>>>> +            }
>>>>>> +            break;
>>>>>> +        case EVENT_TAP_MMIO:
>>>>>> +            cpu_physical_memory_rw(log->mmio.address,
>>>>>> +                                   log->mmio.buf,
>>>>>> +                                   log->mmio.len, 1);
>>>>>> +            break;
>>>>>> +        case 0:
>>>>>> +            trace_event_tap_replay_no_event();
>>>>>> +            break;
>>>>>> +        default:
>>>>>> +            error_report("Unknown state %d", log->mode);
>>>>>> +            QTAILQ_REMOVE(&event_list, log, node);
>>>>>> +            event_tap_free_log(log);
>>>>>> +            return;
>>>>>> +        }
>>>>>> +    }
>>>>>> +
>>>>>> +    /* remove event logs from queue */
>>>>>> +    QTAILQ_FOREACH_SAFE(log,&event_list, node, next) {
>>>>>> +        QTAILQ_REMOVE(&event_list, log, node);
>>>>>> +        event_tap_free_log(log);
>>>>>> +    }
>>>>>> +
>>>>>> +    event_tap_state = EVENT_TAP_OFF;
>>>>>> +    qemu_del_vm_change_state_handler(vmstate);
>>>>>> +}
>>>>>> +
>>>>>> +static void event_tap_save(QEMUFile *f, void *opaque)
>>>>>> +{
>>>>>> +    EventTapLog *log;
>>>>>> +
>>>>>> +    QTAILQ_FOREACH(log,&event_list, node) {
>>>>>> +        qemu_put_byte(f, log->mode);
>>>>>> +
>>>>>> +        switch (log->mode&      EVENT_TAP_TYPE_MASK) {
>>>>>> +        case EVENT_TAP_IOPORT:
>>>>>> +            event_tap_ioport_save(f,&log->ioport);
>>>>>> +            break;
>>>>>> +        case EVENT_TAP_MMIO:
>>>>>> +            event_tap_mmio_save(f,&log->mmio);
>>>>>> +            break;
>>>>>> +        case 0:
>>>>>> +            trace_event_tap_save_no_event();
>>>>>> +            break;
>>>>>> +        default:
>>>>>> +            error_report("Unknown state %d", log->mode);
>>>>>> +            return;
>>>>>> +        }
>>>>>> +
>>>>>> +        switch (log->mode&      ~EVENT_TAP_TYPE_MASK) {
>>>>>> +        case EVENT_TAP_NET:
>>>>>> +            event_tap_net_save(f,&log->net_req);
>>>>>> +            break;
>>>>>> +        case EVENT_TAP_BLK:
>>>>>> +            event_tap_blk_save(f,&log->blk_req);
>>>>>> +            break;
>>>>>> +        default:
>>>>>> +            error_report("Unknown state %d", log->mode);
>>>>>> +            return;
>>>>>> +        }
>>>>>> +    }
>>>>>> +
>>>>>> +    qemu_put_byte(f, 0); /* EOF */
>>>>>> +}
>>>>>> +
>>>>>> +static int event_tap_load(QEMUFile *f, void *opaque, int version_id)
>>>>>> +{
>>>>>> +    EventTapLog *log, *next;
>>>>>> +    int mode;
>>>>>> +
>>>>>> +    event_tap_state = EVENT_TAP_LOAD;
>>>>>> +
>>>>>> +    QTAILQ_FOREACH_SAFE(log,&event_list, node, next) {
>>>>>> +        QTAILQ_REMOVE(&event_list, log, node);
>>>>>> +        event_tap_free_log(log);
>>>>>> +    }
>>>>>> +
>>>>>> +    /* loop until EOF */
>>>>>> +    while ((mode = qemu_get_byte(f)) != 0) {
>>>>>> +        EventTapLog *log = event_tap_alloc_log();
>>>>>> +
>>>>>> +        log->mode = mode;
>>>>>> +        switch (log->mode&      EVENT_TAP_TYPE_MASK) {
>>>>>> +        case EVENT_TAP_IOPORT:
>>>>>> +            event_tap_ioport_load(f,&log->ioport);
>>>>>> +            break;
>>>>>> +        case EVENT_TAP_MMIO:
>>>>>> +            event_tap_mmio_load(f,&log->mmio);
>>>>>> +            break;
>>>>>> +        case 0:
>>>>>> +            trace_event_tap_load_no_event();
>>>>>> +            break;
>>>>>> +        default:
>>>>>> +            error_report("Unknown state %d", log->mode);
>>>>>> +            event_tap_free_log(log);
>>>>>> +            return -EINVAL;
>>>>>> +        }
>>>>>> +
>>>>>> +        switch (log->mode&      ~EVENT_TAP_TYPE_MASK) {
>>>>>> +        case EVENT_TAP_NET:
>>>>>> +            event_tap_net_load(f,&log->net_req);
>>>>>> +            break;
>>>>>> +        case EVENT_TAP_BLK:
>>>>>> +            event_tap_blk_load(f,&log->blk_req);
>>>>>> +            break;
>>>>>> +        default:
>>>>>> +            error_report("Unknown state %d", log->mode);
>>>>>> +            event_tap_free_log(log);
>>>>>> +            return -EINVAL;
>>>>>> +        }
>>>>>> +
>>>>>> +        QTAILQ_INSERT_TAIL(&event_list, log, node);
>>>>>> +    }
>>>>>> +
>>>>>> +    return 0;
>>>>>> +}
>>>>>> +
>>>>>> +void event_tap_schedule_replay(void)
>>>>>> +{
>>>>>> +    vmstate = qemu_add_vm_change_state_handler(event_tap_replay,
>>>>>> NULL);
>>>>>> +}
>>>>>> +
>>>>>> +void event_tap_schedule_suspend(void)
>>>>>> +{
>>>>>> +    vmstate = qemu_add_vm_change_state_handler(event_tap_suspend,
>>>>>> NULL);
>>>>>> +}
>>>>>> +
>>>>>> +void event_tap_init(void)
>>>>>> +{
>>>>>> +    QTAILQ_INIT(&event_list);
>>>>>> +    QTAILQ_INIT(&event_pool);
>>>>>> +    register_savevm(NULL, "event-tap", 0, 1,
>>>>>> +                    event_tap_save, event_tap_load,&last_event_tap);
>>>>>> +}
>>>>>> diff --git a/event-tap.h b/event-tap.h
>>>>>> new file mode 100644
>>>>>> index 0000000..ab677f8
>>>>>> --- /dev/null
>>>>>> +++ b/event-tap.h
>>>>>> @@ -0,0 +1,44 @@
>>>>>> +/*
>>>>>> + * Event Tap functions for QEMU
>>>>>> + *
>>>>>> + * Copyright (c) 2010 Nippon Telegraph and Telephone Corporation.
>>>>>> + *
>>>>>> + * This work is licensed under the terms of the GNU GPL, version 2.
>>>>>>   See
>>>>>> + * the COPYING file in the top-level directory.
>>>>>> + */
>>>>>> +
>>>>>> +#ifndef EVENT_TAP_H
>>>>>> +#define EVENT_TAP_H
>>>>>> +
>>>>>> +#include "qemu-common.h"
>>>>>> +#include "net.h"
>>>>>> +#include "block.h"
>>>>>> +
>>>>>> +int event_tap_register(int (*cb)(void));
>>>>>> +void event_tap_unregister(void);
>>>>>> +int event_tap_is_on(void);
>>>>>> +void event_tap_schedule_suspend(void);
>>>>>> +void event_tap_ioport(int index, uint32_t address, uint32_t data);
>>>>>> +void event_tap_mmio(uint64_t address, uint8_t *buf, int len);
>>>>>> +void event_tap_init(void);
>>>>>> +void event_tap_flush(void);
>>>>>> +int event_tap_flush_one(void);
>>>>>> +void event_tap_schedule_replay(void);
>>>>>> +
>>>>>> +void event_tap_send_packet(VLANClientState *vc, const uint8_t *buf,
>>>>>> int
>>>>>> size);
>>>>>> +ssize_t event_tap_sendv_packet_async(VLANClientState *vc,
>>>>>> +                                     const struct iovec *iov,
>>>>>> +                                     int iovcnt, NetPacketSent
>>>>>> *sent_cb);
>>>>>> +
>>>>>> +BlockDriverAIOCB *event_tap_bdrv_aio_writev(BlockDriverState *bs,
>>>>>> +                                            int64_t sector_num,
>>>>>> +                                            QEMUIOVector *iov,
>>>>>> +                                            int nb_sectors,
>>>>>> +                                            BlockDriverCompletionFunc
>>>>>> *cb,
>>>>>> +                                            void *opaque);
>>>>>> +BlockDriverAIOCB *event_tap_bdrv_aio_flush(BlockDriverState *bs,
>>>>>> +                                           BlockDriverCompletionFunc
>>>>>> *cb,
>>>>>> +                                           void *opaque);
>>>>>> +void event_tap_bdrv_flush(void);
>>>>>> +
>>>>>> +#endif
>>>>>> diff --git a/qemu-tool.c b/qemu-tool.c
>>>>>> index 392e1c9..3f71215 100644
>>>>>> --- a/qemu-tool.c
>>>>>> +++ b/qemu-tool.c
>>>>>> @@ -16,6 +16,7 @@
>>>>>>   #include "qemu-timer.h"
>>>>>>   #include "qemu-log.h"
>>>>>>   #include "sysemu.h"
>>>>>> +#include "event-tap.h"
>>>>>>
>>>>>>   #include<sys/time.h>
>>>>>>
>>>>>> @@ -111,3 +112,30 @@ int qemu_set_fd_handler2(int fd,
>>>>>>   {
>>>>>>      return 0;
>>>>>>   }
>>>>>> +
>>>>>> +BlockDriverAIOCB *event_tap_bdrv_aio_writev(BlockDriverState *bs,
>>>>>> +                                            int64_t sector_num,
>>>>>> +                                            QEMUIOVector *iov,
>>>>>> +                                            int nb_sectors,
>>>>>> +                                            BlockDriverCompletionFunc
>>>>>> *cb,
>>>>>> +                                            void *opaque)
>>>>>> +{
>>>>>> +    return NULL;
>>>>>> +}
>>>>>> +
>>>>>> +BlockDriverAIOCB *event_tap_bdrv_aio_flush(BlockDriverState *bs,
>>>>>> +                                           BlockDriverCompletionFunc
>>>>>> *cb,
>>>>>> +                                           void *opaque)
>>>>>> +{
>>>>>> +    return NULL;
>>>>>> +}
>>>>>> +
>>>>>> +void event_tap_bdrv_flush(void)
>>>>>> +{
>>>>>> +}
>>>>>> +
>>>>>> +int event_tap_is_on(void)
>>>>>> +{
>>>>>> +    return 0;
>>>>>> +}
>>>>>> +
>>>>>> diff --git a/trace-events b/trace-events
>>>>>> index 50ac840..1af3895 100644
>>>>>> --- a/trace-events
>>>>>> +++ b/trace-events
>>>>>> @@ -269,3 +269,13 @@ disable ft_trans_freeze_input(void) "backend not
>>>>>> ready, freezing input"
>>>>>>   disable ft_trans_put_ready(void) "file is ready to put"
>>>>>>   disable ft_trans_get_ready(void) "file is ready to get"
>>>>>>   disable ft_trans_cb(void *cb) "callback %p"
>>>>>> +
>>>>>> +# event-tap.c
>>>>>> +disable event_tap_ignore_bh(int bh) "event_tap_bh is already scheduled
>>>>>> %d"
>>>>>> +disable event_tap_net_cb(char *s, ssize_t len) "%s: %zd bytes packet
>>>>>> was
>>>>>> sended"
>>>>>> +disable event_tap_no_event(void) "no last_event_tap"
>>>>>> +disable event_tap_already_used(int mode) "last_event_tap already used
>>>>>> %d"
>>>>>> +disable event_tap_append_packet(void) "This packet is appended"
>>>>>> +disable event_tap_replay_no_event(void) "No event to replay"
>>>>>> +disable event_tap_save_no_event(void) "No event to save"
>>>>>> +disable event_tap_load_no_event(void) "No event to load"
>>>>>> --
>>>>>> 1.7.1.2
>>>>>>
>>>>>> --
>>>>>> To unsubscribe from this list: send the line "unsubscribe kvm" in
>>>>>> the body of a message to majordomo@vger.kernel.org
>>>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>>>>
>>>>>
>>>>>
>>>>
>>>
>>>
>>
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