On 03/28/2016 07:48 AM, Denis V. Lunev wrote:
> From: Pavel Butsykin <pbutsy...@virtuozzo.com>
>
> Restart of ATAPI DMA used to be unreachable, because the request to do
> so wasn't indicated in bus->error_status due to the lack of spare bits, and
> ide_restart_bh() would return early doing nothing.
>
> This patch makes use of the observation that not all bit combinations were
> possible in ->error_status. In particular, IDE_RETRY_READ only made sense
> together with IDE_RETRY_DMA or IDE_RETRY_PIO. This allows to re-use
> IDE_RETRY_READ alone as an indicator of ATAPI DMA restart request.
>
> To makes things more uniform, ATAPI DMA gets its own value for ->dma_cmd.
> As a means against confusion, macros are added to test the state of
> ->error_status.
>
> The patch fixes the restart of both in-flight and pending ATAPI DMA,
> following the scheme similar to that of IDE DMA.
>
> Signed-off-by: Pavel Butsykin <pbutsy...@virtuozzo.com>
> Reviewed-by: Roman Kagan <rka...@virtuozzo.com>
> Signed-off-by: Denis V. Lunev <d...@openvz.org>
> CC: John Snow <js...@redhat.com>
> ---
> hw/ide/atapi.c | 15 ++++++++-------
> hw/ide/core.c | 27 ++++++++++++---------------
> hw/ide/internal.h | 21 +++++++++++++++++++++
> 3 files changed, 41 insertions(+), 22 deletions(-)
>
> diff --git a/hw/ide/atapi.c b/hw/ide/atapi.c
> index acc52cd..fb9ae43 100644
> --- a/hw/ide/atapi.c
> +++ b/hw/ide/atapi.c
> @@ -342,6 +342,7 @@ static void ide_atapi_cmd_reply(IDEState *s, int size,
> int max_size)
> block_acct_start(blk_get_stats(s->blk), &s->acct, size,
> BLOCK_ACCT_READ);
> s->status = READY_STAT | SEEK_STAT | DRQ_STAT;
> + s->dma_cmd = IDE_DMA_ATAPI;
> ide_start_dma(s, ide_atapi_cmd_read_dma_cb);
> } else {
> s->status = READY_STAT | SEEK_STAT;
> @@ -375,15 +376,18 @@ static void ide_atapi_cmd_check_status(IDEState *s)
> }
> /* ATAPI DMA support */
>
> -/* XXX: handle read errors */
> static void ide_atapi_cmd_read_dma_cb(void *opaque, int ret)
> {
> IDEState *s = opaque;
> int data_offset, n;
>
> if (ret < 0) {
> - ide_atapi_io_error(s, ret);
> - goto eot;
> + if (ide_handle_rw_error(s, -ret, ide_dma_cmd_to_retry(s->dma_cmd))) {
> + if (s->bus->error_status) {
> + return;
> + }
> + goto eot;
> + }
> }
>
> if (s->io_buffer_size > 0) {
> @@ -464,6 +468,7 @@ static void ide_atapi_cmd_read_dma(IDEState *s, int lba,
> int nb_sectors,
>
> /* XXX: check if BUSY_STAT should be set */
> s->status = READY_STAT | SEEK_STAT | DRQ_STAT | BUSY_STAT;
> + s->dma_cmd = IDE_DMA_ATAPI;
> ide_start_dma(s, ide_atapi_cmd_read_dma_cb);
> }
>
> @@ -481,10 +486,6 @@ static void ide_atapi_cmd_read(IDEState *s, int lba, int
> nb_sectors,
> }
> }
>
> -
> -/* Called by *_restart_bh when the transfer function points
> - * to ide_atapi_cmd
> - */
> void ide_atapi_dma_restart(IDEState *s)
> {
> /*
> diff --git a/hw/ide/core.c b/hw/ide/core.c
> index 8f86036..0425d86 100644
> --- a/hw/ide/core.c
> +++ b/hw/ide/core.c
> @@ -56,7 +56,6 @@ static const int smart_attributes[][12] = {
> { 190, 0x03, 0x00, 0x45, 0x45, 0x1f, 0x00, 0x1f, 0x1f, 0x00, 0x00,
> 0x32},
> };
>
> -static int ide_handle_rw_error(IDEState *s, int error, int op);
> static void ide_dummy_transfer_stop(IDEState *s);
>
> static void padstr(char *str, const char *src, int len)
> @@ -772,7 +771,7 @@ void ide_dma_error(IDEState *s)
> ide_set_irq(s->bus);
> }
>
> -static int ide_handle_rw_error(IDEState *s, int error, int op)
> +int ide_handle_rw_error(IDEState *s, int error, int op)
> {
> bool is_read = (op & IDE_RETRY_READ) != 0;
> BlockErrorAction action = blk_get_error_action(s->blk, is_read, error);
> @@ -782,8 +781,10 @@ static int ide_handle_rw_error(IDEState *s, int error,
> int op)
> s->bus->error_status = op;
> } else if (action == BLOCK_ERROR_ACTION_REPORT) {
> block_acct_failed(blk_get_stats(s->blk), &s->acct);
> - if (op & IDE_RETRY_DMA) {
> + if (IS_IDE_RETRY_DMA(op)) {
> ide_dma_error(s);
> + } else if (IS_IDE_RETRY_ATAPI(op)) {
> + ide_atapi_io_error(s, -error);
> } else {
> ide_rw_error(s);
> }
> @@ -871,6 +872,8 @@ static void ide_dma_cb(void *opaque, int ret)
> ide_issue_trim, ide_dma_cb, s,
> DMA_DIRECTION_TO_DEVICE);
> break;
> + default:
> + abort();
> }
> return;
>
> @@ -2517,15 +2520,13 @@ static void ide_restart_bh(void *opaque)
> if (s->bus->dma->ops->restart) {
> s->bus->dma->ops->restart(s->bus->dma);
> }
> - }
> -
> - if (error_status & IDE_RETRY_DMA) {
> + } else if (IS_IDE_RETRY_DMA(error_status)) {
> if (error_status & IDE_RETRY_TRIM) {
> ide_restart_dma(s, IDE_DMA_TRIM);
> } else {
> ide_restart_dma(s, is_read ? IDE_DMA_READ : IDE_DMA_WRITE);
> }
> - } else if (error_status & IDE_RETRY_PIO) {
> + } else if (IS_IDE_RETRY_PIO(error_status)) {
> if (is_read) {
> ide_sector_read(s);
> } else {
> @@ -2533,15 +2534,11 @@ static void ide_restart_bh(void *opaque)
> }
> } else if (error_status & IDE_RETRY_FLUSH) {
> ide_flush_cache(s);
> + } else if (IS_IDE_RETRY_ATAPI(error_status)) {
> + assert(s->end_transfer_func == ide_atapi_cmd);
> + ide_atapi_dma_restart(s);
> } else {
> - /*
> - * We've not got any bits to tell us about ATAPI - but
> - * we do have the end_transfer_func that tells us what
> - * we're trying to do.
> - */
> - if (s->end_transfer_func == ide_atapi_cmd) {
> - ide_atapi_dma_restart(s);
> - }
> + abort();
> }
> }
>
> diff --git a/hw/ide/internal.h b/hw/ide/internal.h
> index 68c7d0d..eb006c2 100644
> --- a/hw/ide/internal.h
> +++ b/hw/ide/internal.h
> @@ -338,6 +338,7 @@ enum ide_dma_cmd {
> IDE_DMA_READ,
> IDE_DMA_WRITE,
> IDE_DMA_TRIM,
> + IDE_DMA_ATAPI
> };
>
> #define ide_cmd_is_read(s) \
> @@ -508,11 +509,27 @@ struct IDEDevice {
> /* These are used for the error_status field of IDEBus */
> #define IDE_RETRY_DMA 0x08
> #define IDE_RETRY_PIO 0x10
> +#define IDE_RETRY_ATAPI 0x20 /* reused IDE_RETRY_READ bit */
> #define IDE_RETRY_READ 0x20
> #define IDE_RETRY_FLUSH 0x40
> #define IDE_RETRY_TRIM 0x80
> #define IDE_RETRY_HBA 0x100
>
> +#define IS_IDE_RETRY_DMA(_status) \
> + ((_status) & IDE_RETRY_DMA)
> +
> +#define IS_IDE_RETRY_PIO(_status) \
> + ((_status) & IDE_RETRY_PIO)
> +
> +/*
> + * The method of the IDE_RETRY_ATAPI determination is to use a previously
> + * impossible bit combination as a new status value.
> + */
> +#define IS_IDE_RETRY_ATAPI(_status) \
> + (((_status) & IDE_RETRY_ATAPI) && \
> + !IS_IDE_RETRY_DMA(_status) && \
> + !IS_IDE_RETRY_PIO(_status))
> +
> static inline uint8_t ide_dma_cmd_to_retry(uint8_t dma_cmd)
> {
> switch (dma_cmd) {
> @@ -522,6 +539,8 @@ static inline uint8_t ide_dma_cmd_to_retry(uint8_t
> dma_cmd)
> return IDE_RETRY_DMA;
> case IDE_DMA_TRIM:
> return IDE_RETRY_DMA | IDE_RETRY_TRIM;
> + case IDE_DMA_ATAPI:
> + return IDE_RETRY_ATAPI;
> default:
> break;
> }
> @@ -612,4 +631,6 @@ void ide_bus_new(IDEBus *idebus, size_t idebus_size,
> DeviceState *dev,
> int bus_id, int max_units);
> IDEDevice *ide_create_drive(IDEBus *bus, int unit, DriveInfo *drive);
>
> +int ide_handle_rw_error(IDEState *s, int error, int op);
> +
> #endif /* HW_IDE_INTERNAL_H */
>
Sorry, I'm afraid this doesn't compile:
/home/bos/jhuston/src/qemu/hw/ide/macio.c: In function
‘pmac_ide_transfer_cb’:
/home/bos/jhuston/src/qemu/hw/ide/macio.c:339:5: error: enumeration
value ‘IDE_DMA_ATAPI’ not handled in switch [-Werror=switch]
switch (s->dma_cmd) {
^
cc1: all warnings being treated as errors
/home/bos/jhuston/src/qemu/rules.mak:57: recipe for target
'hw/ide/macio.o' failed
make: *** [hw/ide/macio.o] Error 1
make: *** Waiting for unfinished jobs....
