The legacy API wrappers in include/linux/pci-dma-compat.h
should go away as it creates unnecessary midlayering
for include/linux/dma-mapping.h APIs, instead use dma-mapping.h
APIs directly.
The patch has been generated with the coccinelle script below
and compile-tested.
@@@@
- PCI_DMA_BIDIRECTIONAL
+ DMA_BIDIRECTIONAL
@@@@
- PCI_DMA_TODEVICE
+ DMA_TO_DEVICE
@@@@
- PCI_DMA_FROMDEVICE
+ DMA_FROM_DEVICE
@@@@
- PCI_DMA_NONE
+ DMA_NONE
@@ expression E1, E2, E3; @@
- pci_alloc_consistent(E1, E2, E3)
+ dma_alloc_coherent(&E1->dev, E2, E3, GFP_ATOMIC)
@@ expression E1, E2, E3; @@
- pci_zalloc_consistent(E1, E2, E3)
+ dma_alloc_coherent(&E1->dev, E2, E3, GFP_ATOMIC)
@@ expression E1, E2, E3, E4; @@
- pci_free_consistent(E1, E2, E3, E4)
+ dma_free_coherent(&E1->dev, E2, E3, E4)
@@ expression E1, E2, E3, E4; @@
- pci_map_single(E1, E2, E3, E4)
+ dma_map_single(&E1->dev, E2, E3, (enum dma_data_direction)E4)
@@ expression E1, E2, E3, E4; @@
- pci_unmap_single(E1, E2, E3, E4)
+ dma_unmap_single(&E1->dev, E2, E3, (enum dma_data_direction)E4)
@@ expression E1, E2, E3, E4, E5; @@
- pci_map_page(E1, E2, E3, E4, E5)
+ dma_map_page(&E1->dev, E2, E3, E4, (enum dma_data_direction)E5)
@@ expression E1, E2, E3, E4; @@
- pci_unmap_page(E1, E2, E3, E4)
+ dma_unmap_page(&E1->dev, E2, E3, (enum dma_data_direction)E4)
@@ expression E1, E2, E3, E4; @@
- pci_map_sg(E1, E2, E3, E4)
+ dma_map_sg(&E1->dev, E2, E3, (enum dma_data_direction)E4)
@@ expression E1, E2, E3, E4; @@
- pci_unmap_sg(E1, E2, E3, E4)
+ dma_unmap_sg(&E1->dev, E2, E3, (enum dma_data_direction)E4)
@@ expression E1, E2, E3, E4; @@
- pci_dma_sync_single_for_cpu(E1, E2, E3, E4)
+ dma_sync_single_for_cpu(&E1->dev, E2, E3, (enum dma_data_direction)E4)
@@ expression E1, E2, E3, E4; @@
- pci_dma_sync_single_for_device(E1, E2, E3, E4)
+ dma_sync_single_for_device(&E1->dev, E2, E3, (enum dma_data_direction)E4)
@@ expression E1, E2, E3, E4; @@
- pci_dma_sync_sg_for_cpu(E1, E2, E3, E4)
+ dma_sync_sg_for_cpu(&E1->dev, E2, E3, (enum dma_data_direction)E4)
@@ expression E1, E2, E3, E4; @@
- pci_dma_sync_sg_for_device(E1, E2, E3, E4)
+ dma_sync_sg_for_device(&E1->dev, E2, E3, (enum dma_data_direction)E4)
@@ expression E1, E2; @@
- pci_dma_mapping_error(E1, E2)
+ dma_mapping_error(&E1->dev, E2)
@@ expression E1, E2; @@
- pci_set_consistent_dma_mask(E1, E2)
+ dma_set_coherent_mask(&E1->dev, E2)
@@ expression E1, E2; @@
- pci_set_dma_mask(E1, E2)
+ dma_set_mask(&E1->dev, E2)
Signed-off-by: Suraj Upadhyay <[email protected]>
---
This change is proposed by Christoph Hellwig <[email protected]>
in the post https://marc.info/?l=kernel-janitors&m=158745678307186&w=4
on kernel-janitors Mailing List.
drivers/staging/comedi/drivers/s626.c | 18 ++++++++++--------
1 file changed, 10 insertions(+), 8 deletions(-)
diff --git a/drivers/staging/comedi/drivers/s626.c b/drivers/staging/comedi/drivers/s626.c
index 084a8e7b9fc2..c159416662fd 100644
--- a/drivers/staging/comedi/drivers/s626.c
+++ b/drivers/staging/comedi/drivers/s626.c
@@ -2130,13 +2130,15 @@ static int s626_allocate_dma_buffers(struct comedi_device *dev)
void *addr;
dma_addr_t appdma;
- addr = pci_alloc_consistent(pcidev, S626_DMABUF_SIZE, &appdma);
+ addr = dma_alloc_coherent(&pcidev->dev, S626_DMABUF_SIZE, &appdma,
+ GFP_ATOMIC);
if (!addr)
return -ENOMEM;
devpriv->ana_buf.logical_base = addr;
devpriv->ana_buf.physical_base = appdma;
- addr = pci_alloc_consistent(pcidev, S626_DMABUF_SIZE, &appdma);
+ addr = dma_alloc_coherent(&pcidev->dev, S626_DMABUF_SIZE, &appdma,
+ GFP_ATOMIC);
if (!addr)
return -ENOMEM;
devpriv->rps_buf.logical_base = addr;
@@ -2154,13 +2156,13 @@ static void s626_free_dma_buffers(struct comedi_device *dev)
return;
if (devpriv->rps_buf.logical_base)
- pci_free_consistent(pcidev, S626_DMABUF_SIZE,
- devpriv->rps_buf.logical_base,
- devpriv->rps_buf.physical_base);
+ dma_free_coherent(&pcidev->dev, S626_DMABUF_SIZE,
+ devpriv->rps_buf.logical_base,
+ devpriv->rps_buf.physical_base);
if (devpriv->ana_buf.logical_base)
- pci_free_consistent(pcidev, S626_DMABUF_SIZE,
- devpriv->ana_buf.logical_base,
- devpriv->ana_buf.physical_base);
+ dma_free_coherent(&pcidev->dev, S626_DMABUF_SIZE,
+ devpriv->ana_buf.logical_base,
+ devpriv->ana_buf.physical_base);
}
static int s626_initialize(struct comedi_device *dev)
--
2.17.1
Le 11/07/2020 ? 14:35, Suraj Upadhyay a ?crit?:
> The legacy API wrappers in include/linux/pci-dma-compat.h
> should go away as it creates unnecessary midlayering
> for include/linux/dma-mapping.h APIs, instead use dma-mapping.h
> APIs directly.
>
> The patch has been generated with the coccinelle script below
> and compile-tested.
>
> [...]
> @@ expression E1, E2, E3; @@
> - pci_alloc_consistent(E1, E2, E3)
> + dma_alloc_coherent(&E1->dev, E2, E3, GFP_ATOMIC)
>
> @@ expression E1, E2, E3; @@
> - pci_zalloc_consistent(E1, E2, E3)
> + dma_alloc_coherent(&E1->dev, E2, E3, GFP_ATOMIC)
This is the tricky part of this kind of cleanup, see below.
GFP_ATOMIC can't be wrong because it is was exactly what was done with
the pci_ function.
However, most of the time, it can safely be replaced by GFP_KERNEL which
gives more opportunities to the memory allocator.
> [...]
> diff --git a/drivers/staging/comedi/drivers/s626.c b/drivers/staging/comedi/drivers/s626.c
> index 084a8e7b9fc2..c159416662fd 100644
> --- a/drivers/staging/comedi/drivers/s626.c
> +++ b/drivers/staging/comedi/drivers/s626.c
> @@ -2130,13 +2130,15 @@ static int s626_allocate_dma_buffers(struct comedi_device *dev)
> void *addr;
> dma_addr_t appdma;
>
> - addr = pci_alloc_consistent(pcidev, S626_DMABUF_SIZE, &appdma);
> + addr = dma_alloc_coherent(&pcidev->dev, S626_DMABUF_SIZE, &appdma,
> + GFP_ATOMIC);
> if (!addr)
> return -ENOMEM;
> devpriv->ana_buf.logical_base = addr;
> devpriv->ana_buf.physical_base = appdma;
>
> - addr = pci_alloc_consistent(pcidev, S626_DMABUF_SIZE, &appdma);
> + addr = dma_alloc_coherent(&pcidev->dev, S626_DMABUF_SIZE, &appdma,
> + GFP_ATOMIC);
> if (!addr)
> return -ENOMEM;
> devpriv->rps_buf.logical_base = addr;
's626_allocate_dma_buffers()' is only called from 's626_auto_attach()'.
In this function, around the call to 's626_allocate_dma_buffers()', you
can see:
? - a few lines before, a call to 'comedi_alloc_devpriv()'
? - a few lines after, a call to 'comedi_alloc_subdevices()'
These 2 functions make some memory allocation using GFP_KERNEL.
So it is likely that using GFP_KERNEL in your proposal is also valid.
Just my 2c.
CJ
On 11/07/2020 14:38, Christophe JAILLET wrote:
> Le 11/07/2020 ? 14:35, Suraj Upadhyay a ?crit?:
>> The legacy API wrappers in include/linux/pci-dma-compat.h
>> should go away as it creates unnecessary midlayering
>> for include/linux/dma-mapping.h APIs, instead use dma-mapping.h
>> APIs directly.
>>
>> The patch has been generated with the coccinelle script below
>> and compile-tested.
>>
>> [...]
>> @@ expression E1, E2, E3; @@
>> - pci_alloc_consistent(E1, E2, E3)
>> + dma_alloc_coherent(&E1->dev, E2, E3, GFP_ATOMIC)
>>
>> @@ expression E1, E2, E3; @@
>> - pci_zalloc_consistent(E1, E2, E3)
>> + dma_alloc_coherent(&E1->dev, E2, E3, GFP_ATOMIC)
>
> This is the tricky part of this kind of cleanup, see below.
>
> GFP_ATOMIC can't be wrong because it is was exactly what was done with
> the pci_ function.
> However, most of the time, it can safely be replaced by GFP_KERNEL which
> gives more opportunities to the memory allocator.
>
>> [...]
>> diff --git a/drivers/staging/comedi/drivers/s626.c
>> b/drivers/staging/comedi/drivers/s626.c
>> index 084a8e7b9fc2..c159416662fd 100644
>> --- a/drivers/staging/comedi/drivers/s626.c
>> +++ b/drivers/staging/comedi/drivers/s626.c
>> @@ -2130,13 +2130,15 @@ static int s626_allocate_dma_buffers(struct
>> comedi_device *dev)
>> ????? void *addr;
>> ????? dma_addr_t appdma;
>> -??? addr = pci_alloc_consistent(pcidev, S626_DMABUF_SIZE, &appdma);
>> +??? addr = dma_alloc_coherent(&pcidev->dev, S626_DMABUF_SIZE, &appdma,
>> +????????????????? GFP_ATOMIC);
>> ????? if (!addr)
>> ????????? return -ENOMEM;
>> ????? devpriv->ana_buf.logical_base = addr;
>> ????? devpriv->ana_buf.physical_base = appdma;
>> -??? addr = pci_alloc_consistent(pcidev, S626_DMABUF_SIZE, &appdma);
>> +??? addr = dma_alloc_coherent(&pcidev->dev, S626_DMABUF_SIZE, &appdma,
>> +????????????????? GFP_ATOMIC);
>> ????? if (!addr)
>> ????????? return -ENOMEM;
>> ????? devpriv->rps_buf.logical_base = addr;
> 's626_allocate_dma_buffers()' is only called from 's626_auto_attach()'.
> In this function, around the call to 's626_allocate_dma_buffers()', you
> can see:
> ? - a few lines before, a call to 'comedi_alloc_devpriv()'
>
> ? - a few lines after, a call to 'comedi_alloc_subdevices()'
>
> These 2 functions make some memory allocation using GFP_KERNEL.
>
> So it is likely that using GFP_KERNEL in your proposal is also valid.
Indeed, GFP_KERNEL is perfectly fine here. It could be done as a
follow-up patch, or done in a v2 of this patch with a mention in the
patch description.
--
-=( Ian Abbott <[email protected]> || Web: http://www.mev.co.uk )=-
-=( MEV Ltd. is a company registered in England & Wales. )=-
-=( Registered number: 02862268. Registered address: )=-
-=( 15 West Park Road, Bramhall, STOCKPORT, SK7 3JZ, UK. )=-