Commit e82dabd8 authored by Stefan Hajnoczi's avatar Stefan Hajnoczi Committed by Kevin Wolf
Browse files

ide: convert ide_sector_write() to asynchronous I/O 



The IDE PIO write sector code path uses bdrv_write() and hence can make
the guest unresponsive while the I/O request is in progress.  This patch
converts ide_sector_write() to use bdrv_aio_writev() by using the
BUSY_STAT bit to tell the guest that the request is in progress.

Signed-off-by: default avatarStefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Reviewed-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: default avatarZhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Tested-by: default avatarRichard Davies <richard@arachsys.com>
Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
parent bef0fd59

hw/ide/core.c

+42 −19
Original line number Diff line number Diff line
@@ -688,40 +688,39 @@ static void ide_sector_write_timer_cb(void *opaque) 
    ide_set_irq(s->bus);

}



void ide_sector_write(IDEState *s)

static void ide_sector_write_cb(void *opaque, int ret)

{

    int64_t sector_num;

    int ret, n, n1;



    s->status = READY_STAT | SEEK_STAT;

    sector_num = ide_get_sector(s);

#if defined(DEBUG_IDE)

    printf("write sector=%" PRId64 "\n", sector_num);

#endif

    n = s->nsector;

    if (n > s->req_nb_sectors)

        n = s->req_nb_sectors;

    IDEState *s = opaque;

    int n;



    bdrv_acct_start(s->bs, &s->acct, n * BDRV_SECTOR_SIZE, BDRV_ACCT_READ);

    ret = bdrv_write(s->bs, sector_num, s->io_buffer, n);

    bdrv_acct_done(s->bs, &s->acct);



    s->pio_aiocb = NULL;

    s->status &= ~BUSY_STAT;



    if (ret != 0) {

        if (ide_handle_rw_error(s, -ret, BM_STATUS_PIO_RETRY))

        if (ide_handle_rw_error(s, -ret, BM_STATUS_PIO_RETRY)) {

            return;

        }

    }



    n = s->nsector;

    if (n > s->req_nb_sectors) {

        n = s->req_nb_sectors;

    }

    s->nsector -= n;

    if (s->nsector == 0) {

        /* no more sectors to write */

        ide_transfer_stop(s);

    } else {

        n1 = s->nsector;

        if (n1 > s->req_nb_sectors)

        int n1 = s->nsector;

        if (n1 > s->req_nb_sectors) {

            n1 = s->req_nb_sectors;

        ide_transfer_start(s, s->io_buffer, 512 * n1, ide_sector_write);

        }

    ide_set_sector(s, sector_num + n);

        ide_transfer_start(s, s->io_buffer, n1 * BDRV_SECTOR_SIZE,

                           ide_sector_write);

    }

    ide_set_sector(s, ide_get_sector(s) + n);



    if (win2k_install_hack && ((++s->irq_count % 16) == 0)) {

        /* It seems there is a bug in the Windows 2000 installer HDD
@@ -737,6 +736,30 @@ void ide_sector_write(IDEState *s) 
    }

}



void ide_sector_write(IDEState *s)

{

    int64_t sector_num;

    int n;



    s->status = READY_STAT | SEEK_STAT | BUSY_STAT;

    sector_num = ide_get_sector(s);

#if defined(DEBUG_IDE)

    printf("sector=%" PRId64 "\n", sector_num);

#endif

    n = s->nsector;

    if (n > s->req_nb_sectors) {

        n = s->req_nb_sectors;

    }



    s->iov.iov_base = s->io_buffer;

    s->iov.iov_len  = n * BDRV_SECTOR_SIZE;

    qemu_iovec_init_external(&s->qiov, &s->iov, 1);



    bdrv_acct_start(s->bs, &s->acct, n * BDRV_SECTOR_SIZE, BDRV_ACCT_READ);

    s->pio_aiocb = bdrv_aio_writev(s->bs, sector_num, &s->qiov, n,

                                   ide_sector_write_cb, s);

}



static void ide_flush_cb(void *opaque, int ret)

{

    IDEState *s = opaque;