Re: [PATCH] scsi: fix dma_unmap_sg() parameter in some drivers

["chenxiang (M)" <chenxiang66@xxxxxxxxxxxxx>]

在 2018/1/2 18:51, John Garry 写道:
> On 21/12/2017 08:15, chenxiang wrote:
> > For function dma_unmap_sg(), the <nents> parameter should be number of
> > elements in the scatterlist prior to the mapping, not after the mapping.
> > So fix this usage in ibmvscsi_tgt/isci/mvsas/pm8001.
>
> Hi chenxiang,
>
> I think that it may be better to rewrite the series with a patch per 
> driver, so that we can add specific "fixes" ID tag. Please also 
> include "CC:" tag per patch, cc'ing the respective driver maintainer 
> (if any).

Ok, i will split it with a patch per driver.

> BTW, I guess that there are many more instances of this issue 
> throughout the kernel...
>
> Much appreciated,
> John
>
> > Signed-off-by: Xiang Chen <chenxiang66@xxxxxxxxxxxxx>
> > ---
> >  drivers/scsi/ibmvscsi_tgt/libsrp.c | 6 ++++--
> >  drivers/scsi/isci/request.c        | 2 +-
> >  drivers/scsi/mvsas/mv_sas.c        | 4 ++--
> >  drivers/scsi/pm8001/pm8001_sas.c   | 2 +-
> >  4 files changed, 8 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/scsi/ibmvscsi_tgt/libsrp.c 
> > b/drivers/scsi/ibmvscsi_tgt/libsrp.c
> > index 5a4cc28..16054c0 100644
> > --- a/drivers/scsi/ibmvscsi_tgt/libsrp.c
> > +++ b/drivers/scsi/ibmvscsi_tgt/libsrp.c
> > @@ -193,7 +193,8 @@ static int srp_direct_data(struct ibmvscsis_cmd 
> > *cmd, struct srp_direct_buf *md,
> >      err = rdma_io(cmd, sg, nsg, md, 1, dir, len);
> >
> >      if (dma_map)
> > -        dma_unmap_sg(iue->target->dev, sg, nsg, DMA_BIDIRECTIONAL);
> > +        dma_unmap_sg(iue->target->dev, sg, cmd->se_cmd.t_data_nents,
> > +                DMA_BIDIRECTIONAL);
> >
> >      return err;
> >  }
> > @@ -265,7 +266,8 @@ static int srp_indirect_data(struct ibmvscsis_cmd 
> > *cmd, struct srp_cmd *srp_cmd,
> >      err = rdma_io(cmd, sg, nsg, md, nmd, dir, len);
> >
> >      if (dma_map)
> > -        dma_unmap_sg(iue->target->dev, sg, nsg, DMA_BIDIRECTIONAL);
> > +        dma_unmap_sg(iue->target->dev, sg, cmd->se_cmd.t_data_nents,
> > +                DMA_BIDIRECTIONAL);
> >
> >  free_mem:
> >      if (token && dma_map) {
> > diff --git a/drivers/scsi/isci/request.c b/drivers/scsi/isci/request.c
> > index ed197bc..225d947 100644
> > --- a/drivers/scsi/isci/request.c
> > +++ b/drivers/scsi/isci/request.c
> > @@ -2914,7 +2914,7 @@ static void 
> > isci_request_io_request_complete(struct isci_host *ihost,
> >                       task->total_xfer_len, task->data_dir);
> >          else  /* unmap the sgl dma addresses */
> >              dma_unmap_sg(&ihost->pdev->dev, task->scatter,
> > -                     request->num_sg_entries, task->data_dir);
> > +                     task->num_scatter, task->data_dir);
> >          break;
> >      case SAS_PROTOCOL_SMP: {
> >          struct scatterlist *sg = &task->smp_task.smp_req;
> > diff --git a/drivers/scsi/mvsas/mv_sas.c b/drivers/scsi/mvsas/mv_sas.c
> > index cff43bd..4b2cf36 100644
> > --- a/drivers/scsi/mvsas/mv_sas.c
> > +++ b/drivers/scsi/mvsas/mv_sas.c
> > @@ -848,7 +848,7 @@ static int mvs_task_prep(struct sas_task *task, 
> > struct mvs_info *mvi, int is_tmf
> >      dev_printk(KERN_ERR, mvi->dev, "mvsas prep failed[%d]!\n", rc);
> >      if (!sas_protocol_ata(task->task_proto))
> >          if (n_elem)
> > -            dma_unmap_sg(mvi->dev, task->scatter, n_elem,
> > +            dma_unmap_sg(mvi->dev, task->scatter, task->num_scatter,
> >                       task->data_dir);
> >  prep_out:
> >      return rc;
> > @@ -899,7 +899,7 @@ static void mvs_slot_task_free(struct mvs_info 
> > *mvi, struct sas_task *task,
> >      if (!sas_protocol_ata(task->task_proto))
> >          if (slot->n_elem)
> >              dma_unmap_sg(mvi->dev, task->scatter,
> > -                     slot->n_elem, task->data_dir);
> > +                     task->num_scatter, task->data_dir);
> >
> >      switch (task->task_proto) {
> >      case SAS_PROTOCOL_SMP:
> > diff --git a/drivers/scsi/pm8001/pm8001_sas.c 
> > b/drivers/scsi/pm8001/pm8001_sas.c
> > index 947d601..576a0f0 100644
> > --- a/drivers/scsi/pm8001/pm8001_sas.c
> > +++ b/drivers/scsi/pm8001/pm8001_sas.c
> > @@ -466,7 +466,7 @@ static int pm8001_task_exec(struct sas_task *task,
> >      dev_printk(KERN_ERR, pm8001_ha->dev, "pm8001 exec 
> > failed[%d]!\n", rc);
> >      if (!sas_protocol_ata(t->task_proto))
> >          if (n_elem)
> > -            dma_unmap_sg(pm8001_ha->dev, t->scatter, n_elem,
> > +            dma_unmap_sg(pm8001_ha->dev, t->scatter, t->num_scatter,
> >                  t->data_dir);
> >  out_done:
> >      spin_unlock_irqrestore(&pm8001_ha->lock, flags);
>
>
>
> .