2019-06-11 03:29:59

by Finn Thain

Subject: [PATCH] NCR5380: Support chained sg lists

My understanding is that support for chained scatterlists is to
become mandatory for LLDs.

Cc: Michael Schmitz <[email protected]>
Signed-off-by: Finn Thain <[email protected]>
---
drivers/scsi/NCR5380.c | 41 ++++++++++++++++++-----------------------
1 file changed, 18 insertions(+), 23 deletions(-)

diff --git a/drivers/scsi/NCR5380.c b/drivers/scsi/NCR5380.c
index d9fa9cf2fd8b..536426f25e86 100644
--- a/drivers/scsi/NCR5380.c
+++ b/drivers/scsi/NCR5380.c
@@ -149,12 +149,10 @@ static inline void initialize_SCp(struct scsi_cmnd *cmd)

if (scsi_bufflen(cmd)) {
cmd->SCp.buffer = scsi_sglist(cmd);
- cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1;
cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
cmd->SCp.this_residual = cmd->SCp.buffer->length;
} else {
cmd->SCp.buffer = NULL;
- cmd->SCp.buffers_residual = 0;
cmd->SCp.ptr = NULL;
cmd->SCp.this_residual = 0;
}
@@ -163,6 +161,17 @@ static inline void initialize_SCp(struct scsi_cmnd *cmd)
cmd->SCp.Message = 0;
}

+static inline void advance_sg_buffer(struct scsi_cmnd *cmd)
+{
+ struct scatterlist *s = cmd->SCp.buffer;
+
+ if (!cmd->SCp.this_residual && s && !sg_is_last(s)) {
+ cmd->SCp.buffer = sg_next(s);
+ cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
+ cmd->SCp.this_residual = cmd->SCp.buffer->length;
+ }
+}
+
/**
* NCR5380_poll_politely2 - wait for two chip register values
* @hostdata: host private data
@@ -1670,12 +1679,7 @@ static void NCR5380_information_transfer(struct Scsi_Host *instance)
sun3_dma_setup_done != cmd) {
int count;

- if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
- ++cmd->SCp.buffer;
- --cmd->SCp.buffers_residual;
- cmd->SCp.this_residual = cmd->SCp.buffer->length;
- cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
- }
+ advance_sg_buffer(cmd);

count = sun3scsi_dma_xfer_len(hostdata, cmd);

@@ -1725,15 +1729,11 @@ static void NCR5380_information_transfer(struct Scsi_Host *instance)
* scatter-gather list, move onto the next one.
*/

- if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
- ++cmd->SCp.buffer;
- --cmd->SCp.buffers_residual;
- cmd->SCp.this_residual = cmd->SCp.buffer->length;
- cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
- dsprintk(NDEBUG_INFORMATION, instance, "%d bytes and %d buffers left\n",
- cmd->SCp.this_residual,
- cmd->SCp.buffers_residual);
- }
+ advance_sg_buffer(cmd);
+ dsprintk(NDEBUG_INFORMATION, instance,
+ "this residual %d, sg ents %d\n",
+ cmd->SCp.this_residual,
+ sg_nents(cmd->SCp.buffer));

/*
* The preferred transfer method is going to be
@@ -2126,12 +2126,7 @@ static void NCR5380_reselect(struct Scsi_Host *instance)
if (sun3_dma_setup_done != tmp) {
int count;

- if (!tmp->SCp.this_residual && tmp->SCp.buffers_residual) {
- ++tmp->SCp.buffer;
- --tmp->SCp.buffers_residual;
- tmp->SCp.this_residual = tmp->SCp.buffer->length;
- tmp->SCp.ptr = sg_virt(tmp->SCp.buffer);
- }
+ advance_sg_buffer(tmp);

count = sun3scsi_dma_xfer_len(hostdata, tmp);

--
2.21.0

2019-06-11 05:10:27

by Michael Schmitz

Subject: Re: [PATCH] NCR5380: Support chained sg lists

Hi Finn,

Thanks - can't test this on my hardware but looks good to me.

Cheers,

Michael

Am 11.06.2019 um 15:25 schrieb Finn Thain:
> My understanding is that support for chained scatterlists is to
> become mandatory for LLDs.
>
> Cc: Michael Schmitz <[email protected]>
> Signed-off-by: Finn Thain <[email protected]>
> ---
> drivers/scsi/NCR5380.c | 41 ++++++++++++++++++-----------------------
> 1 file changed, 18 insertions(+), 23 deletions(-)
>
> diff --git a/drivers/scsi/NCR5380.c b/drivers/scsi/NCR5380.c
> index d9fa9cf2fd8b..536426f25e86 100644
> --- a/drivers/scsi/NCR5380.c
> +++ b/drivers/scsi/NCR5380.c
> @@ -149,12 +149,10 @@ static inline void initialize_SCp(struct scsi_cmnd *cmd)
>
> if (scsi_bufflen(cmd)) {
> cmd->SCp.buffer = scsi_sglist(cmd);
> - cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1;
> cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
> cmd->SCp.this_residual = cmd->SCp.buffer->length;
> } else {
> cmd->SCp.buffer = NULL;
> - cmd->SCp.buffers_residual = 0;
> cmd->SCp.ptr = NULL;
> cmd->SCp.this_residual = 0;
> }
> @@ -163,6 +161,17 @@ static inline void initialize_SCp(struct scsi_cmnd *cmd)
> cmd->SCp.Message = 0;
> }
>
> +static inline void advance_sg_buffer(struct scsi_cmnd *cmd)
> +{
> + struct scatterlist *s = cmd->SCp.buffer;
> +
> + if (!cmd->SCp.this_residual && s && !sg_is_last(s)) {
> + cmd->SCp.buffer = sg_next(s);
> + cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
> + cmd->SCp.this_residual = cmd->SCp.buffer->length;
> + }
> +}
> +
> /**
> * NCR5380_poll_politely2 - wait for two chip register values
> * @hostdata: host private data
> @@ -1670,12 +1679,7 @@ static void NCR5380_information_transfer(struct Scsi_Host *instance)
> sun3_dma_setup_done != cmd) {
> int count;
>
> - if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
> - ++cmd->SCp.buffer;
> - --cmd->SCp.buffers_residual;
> - cmd->SCp.this_residual = cmd->SCp.buffer->length;
> - cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
> - }
> + advance_sg_buffer(cmd);
>
> count = sun3scsi_dma_xfer_len(hostdata, cmd);
>
> @@ -1725,15 +1729,11 @@ static void NCR5380_information_transfer(struct Scsi_Host *instance)
> * scatter-gather list, move onto the next one.
> */
>
> - if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
> - ++cmd->SCp.buffer;
> - --cmd->SCp.buffers_residual;
> - cmd->SCp.this_residual = cmd->SCp.buffer->length;
> - cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
> - dsprintk(NDEBUG_INFORMATION, instance, "%d bytes and %d buffers left\n",
> - cmd->SCp.this_residual,
> - cmd->SCp.buffers_residual);
> - }
> + advance_sg_buffer(cmd);
> + dsprintk(NDEBUG_INFORMATION, instance,
> + "this residual %d, sg ents %d\n",
> + cmd->SCp.this_residual,
> + sg_nents(cmd->SCp.buffer));
>
> /*
> * The preferred transfer method is going to be
> @@ -2126,12 +2126,7 @@ static void NCR5380_reselect(struct Scsi_Host *instance)
> if (sun3_dma_setup_done != tmp) {
> int count;
>
> - if (!tmp->SCp.this_residual && tmp->SCp.buffers_residual) {
> - ++tmp->SCp.buffer;
> - --tmp->SCp.buffers_residual;
> - tmp->SCp.this_residual = tmp->SCp.buffer->length;
> - tmp->SCp.ptr = sg_virt(tmp->SCp.buffer);
> - }
> + advance_sg_buffer(tmp);
>
> count = sun3scsi_dma_xfer_len(hostdata, tmp);
>
>

2019-06-11 09:47:14

by Finn Thain

Subject: Re: [PATCH] NCR5380: Support chained sg lists

On Tue, 11 Jun 2019, Michael Schmitz wrote:

> Hi Finn,
>
> Thanks - can't test this on my hardware but looks good to me.
>

Thanks for looking it over.

Would you be willing to send a "reviewed-by" tag?

I tested this successfully on my PowerBook 180 using the parameters
mac_scsi.setup_sg_tablesize=128 mac_scsi.setup_use_pdma=0

(Only because PDMA doesn't work with sg_tablesize > 1 with this particular
drive.)

--

> Cheers,
>
> Michael
>
> Am 11.06.2019 um 15:25 schrieb Finn Thain:
> > My understanding is that support for chained scatterlists is to
> > become mandatory for LLDs.
> >
> > Cc: Michael Schmitz <[email protected]>
> > Signed-off-by: Finn Thain <[email protected]>
> > ---
> > drivers/scsi/NCR5380.c | 41 ++++++++++++++++++-----------------------
> > 1 file changed, 18 insertions(+), 23 deletions(-)
> >
> > diff --git a/drivers/scsi/NCR5380.c b/drivers/scsi/NCR5380.c
> > index d9fa9cf2fd8b..536426f25e86 100644
> > --- a/drivers/scsi/NCR5380.c
> > +++ b/drivers/scsi/NCR5380.c
> > @@ -149,12 +149,10 @@ static inline void initialize_SCp(struct scsi_cmnd
> > *cmd)
> >
> > if (scsi_bufflen(cmd)) {
> > cmd->SCp.buffer = scsi_sglist(cmd);
> > - cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1;
> > cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
> > cmd->SCp.this_residual = cmd->SCp.buffer->length;
> > } else {
> > cmd->SCp.buffer = NULL;
> > - cmd->SCp.buffers_residual = 0;
> > cmd->SCp.ptr = NULL;
> > cmd->SCp.this_residual = 0;
> > }
> > @@ -163,6 +161,17 @@ static inline void initialize_SCp(struct scsi_cmnd
> > *cmd)
> > cmd->SCp.Message = 0;
> > }
> >
> > +static inline void advance_sg_buffer(struct scsi_cmnd *cmd)
> > +{
> > + struct scatterlist *s = cmd->SCp.buffer;
> > +
> > + if (!cmd->SCp.this_residual && s && !sg_is_last(s)) {
> > + cmd->SCp.buffer = sg_next(s);
> > + cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
> > + cmd->SCp.this_residual = cmd->SCp.buffer->length;
> > + }
> > +}
> > +
> > /**
> > * NCR5380_poll_politely2 - wait for two chip register values
> > * @hostdata: host private data
> > @@ -1670,12 +1679,7 @@ static void NCR5380_information_transfer(struct
> > Scsi_Host *instance)
> > sun3_dma_setup_done != cmd) {
> > int count;
> >
> > - if (!cmd->SCp.this_residual &&
> > cmd->SCp.buffers_residual) {
> > - ++cmd->SCp.buffer;
> > - --cmd->SCp.buffers_residual;
> > - cmd->SCp.this_residual =
> > cmd->SCp.buffer->length;
> > - cmd->SCp.ptr =
> > sg_virt(cmd->SCp.buffer);
> > - }
> > + advance_sg_buffer(cmd);
> >
> > count = sun3scsi_dma_xfer_len(hostdata, cmd);
> >
> > @@ -1725,15 +1729,11 @@ static void NCR5380_information_transfer(struct
> > Scsi_Host *instance)
> > * scatter-gather list, move onto the next
> > one.
> > */
> >
> > - if (!cmd->SCp.this_residual &&
> > cmd->SCp.buffers_residual) {
> > - ++cmd->SCp.buffer;
> > - --cmd->SCp.buffers_residual;
> > - cmd->SCp.this_residual =
> > cmd->SCp.buffer->length;
> > - cmd->SCp.ptr =
> > sg_virt(cmd->SCp.buffer);
> > - dsprintk(NDEBUG_INFORMATION, instance,
> > "%d bytes and %d buffers left\n",
> > - cmd->SCp.this_residual,
> > - cmd->SCp.buffers_residual);
> > - }
> > + advance_sg_buffer(cmd);
> > + dsprintk(NDEBUG_INFORMATION, instance,
> > + "this residual %d, sg ents %d\n",
> > + cmd->SCp.this_residual,
> > + sg_nents(cmd->SCp.buffer));
> >
> > /*
> > * The preferred transfer method is going to
> > be
> > @@ -2126,12 +2126,7 @@ static void NCR5380_reselect(struct Scsi_Host
> > *instance)
> > if (sun3_dma_setup_done != tmp) {
> > int count;
> >
> > - if (!tmp->SCp.this_residual && tmp->SCp.buffers_residual) {
> > - ++tmp->SCp.buffer;
> > - --tmp->SCp.buffers_residual;
> > - tmp->SCp.this_residual = tmp->SCp.buffer->length;
> > - tmp->SCp.ptr = sg_virt(tmp->SCp.buffer);
> > - }
> > + advance_sg_buffer(tmp);
> >
> > count = sun3scsi_dma_xfer_len(hostdata, tmp);
> >
> >
>

2019-06-12 07:10:57

by Michael Schmitz

Subject: Re: [PATCH] NCR5380: Support chained sg lists

On 11/06/19 3:25 PM, Finn Thain wrote:

> My understanding is that support for chained scatterlists is to
> become mandatory for LLDs.
>
> Cc: Michael Schmitz <[email protected]>
> Signed-off-by: Finn Thain <[email protected]>
Reviewed-by: Michael Schmitz <[email protected]>
> ---
> drivers/scsi/NCR5380.c | 41 ++++++++++++++++++-----------------------
> 1 file changed, 18 insertions(+), 23 deletions(-)
>
> diff --git a/drivers/scsi/NCR5380.c b/drivers/scsi/NCR5380.c
> index d9fa9cf2fd8b..536426f25e86 100644
> --- a/drivers/scsi/NCR5380.c
> +++ b/drivers/scsi/NCR5380.c
> @@ -149,12 +149,10 @@ static inline void initialize_SCp(struct scsi_cmnd *cmd)
>
> if (scsi_bufflen(cmd)) {
> cmd->SCp.buffer = scsi_sglist(cmd);
> - cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1;
> cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
> cmd->SCp.this_residual = cmd->SCp.buffer->length;
> } else {
> cmd->SCp.buffer = NULL;
> - cmd->SCp.buffers_residual = 0;
> cmd->SCp.ptr = NULL;
> cmd->SCp.this_residual = 0;
> }
> @@ -163,6 +161,17 @@ static inline void initialize_SCp(struct scsi_cmnd *cmd)
> cmd->SCp.Message = 0;
> }
>
> +static inline void advance_sg_buffer(struct scsi_cmnd *cmd)
> +{
> + struct scatterlist *s = cmd->SCp.buffer;
> +
> + if (!cmd->SCp.this_residual && s && !sg_is_last(s)) {
> + cmd->SCp.buffer = sg_next(s);
> + cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
> + cmd->SCp.this_residual = cmd->SCp.buffer->length;
> + }
> +}
> +
> /**
> * NCR5380_poll_politely2 - wait for two chip register values
> * @hostdata: host private data
> @@ -1670,12 +1679,7 @@ static void NCR5380_information_transfer(struct Scsi_Host *instance)
> sun3_dma_setup_done != cmd) {
> int count;
>
> - if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
> - ++cmd->SCp.buffer;
> - --cmd->SCp.buffers_residual;
> - cmd->SCp.this_residual = cmd->SCp.buffer->length;
> - cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
> - }
> + advance_sg_buffer(cmd);
>
> count = sun3scsi_dma_xfer_len(hostdata, cmd);
>
> @@ -1725,15 +1729,11 @@ static void NCR5380_information_transfer(struct Scsi_Host *instance)
> * scatter-gather list, move onto the next one.
> */
>
> - if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
> - ++cmd->SCp.buffer;
> - --cmd->SCp.buffers_residual;
> - cmd->SCp.this_residual = cmd->SCp.buffer->length;
> - cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
> - dsprintk(NDEBUG_INFORMATION, instance, "%d bytes and %d buffers left\n",
> - cmd->SCp.this_residual,
> - cmd->SCp.buffers_residual);
> - }
> + advance_sg_buffer(cmd);
> + dsprintk(NDEBUG_INFORMATION, instance,
> + "this residual %d, sg ents %d\n",
> + cmd->SCp.this_residual,
> + sg_nents(cmd->SCp.buffer));
>
> /*
> * The preferred transfer method is going to be
> @@ -2126,12 +2126,7 @@ static void NCR5380_reselect(struct Scsi_Host *instance)
> if (sun3_dma_setup_done != tmp) {
> int count;
>
> - if (!tmp->SCp.this_residual && tmp->SCp.buffers_residual) {
> - ++tmp->SCp.buffer;
> - --tmp->SCp.buffers_residual;
> - tmp->SCp.this_residual = tmp->SCp.buffer->length;
> - tmp->SCp.ptr = sg_virt(tmp->SCp.buffer);
> - }
> + advance_sg_buffer(tmp);
>
> count = sun3scsi_dma_xfer_len(hostdata, tmp);
>