diff options
| author | Pavel Butsykin <pbutsykin@virtuozzo.com> | 2016-04-12 16:47:52 -0400 |
|---|---|---|
| committer | John Snow <jsnow@redhat.com> | 2016-04-12 16:47:52 -0400 |
| commit | 9a41826f3843bf11bf8f52f176071f8c1fb0aa7e (patch) | |
| tree | e6412f738c4297dacc560dd55046f2485ae6b1a8 | |
| parent | 218fd37c68e450dffe37832e82a1f0a6592e7169 (diff) | |
| download | qemu-9a41826f3843bf11bf8f52f176071f8c1fb0aa7e.tar.gz | |
ide: restart atapi dma by re-evaluating command packet
ide_atapi_dma_restart() used to just complete the DMA with an error,
under the assumption that there isn't enough information to restart it.
However, as the contents of the ->io_buffer is preserved, it looks safe to
just re-evaluate it and dispatch the ATAPI command again.
Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 1459924806-306-3-git-send-email-den@openvz.org
Signed-off-by: John Snow <jsnow@redhat.com>
| -rw-r--r-- | hw/ide/atapi.c | 13 |
1 files changed, 6 insertions, 7 deletions
diff --git a/hw/ide/atapi.c b/hw/ide/atapi.c index 1fe58ab7fd..acc52cd11f 100644 --- a/hw/ide/atapi.c +++ b/hw/ide/atapi.c @@ -488,14 +488,13 @@ static void ide_atapi_cmd_read(IDEState *s, int lba, int nb_sectors, void ide_atapi_dma_restart(IDEState *s) { /* - * I'm not sure we have enough stored to restart the command - * safely, so give the guest an error it should recover from. - * I'm assuming most guests will try to recover from something - * listed as a medium error on a CD; it seems to work on Linux. - * This would be more of a problem if we did any other type of - * DMA operation. + * At this point we can just re-evaluate the packet command and start over. + * The presence of ->dma_cb callback in the pre_save ensures that the packet + * command has been completely sent and we can safely restart command. */ - ide_atapi_cmd_error(s, MEDIUM_ERROR, ASC_NO_SEEK_COMPLETE); + s->unit = s->bus->retry_unit; + s->bus->dma->ops->restart_dma(s->bus->dma); + ide_atapi_cmd(s); } static inline uint8_t ide_atapi_set_profile(uint8_t *buf, uint8_t *index, |