Re: [PATCH v2] fpga: dfl: afu: convert get_user_pages() --> pin_user_pages()
On 2020-05-24 19:25, Wu, Hao wrote: Hi Moritz and FPGA developers, Is this OK? And if so, is it going into your git tree? Or should I send it up through a different tree? (I'm new to the FPGA development model). I can take it, sorry for sluggish response. That's great news, thanks Moritz! Sorry to be pushy, just didn't want it to get lost. :) Thanks John for this patch, and thanks Moritz for taking care of this. Sorry for late response, one thing here we may need to be careful is a recent bug fixing patch, that fixing patch has been merged by Greg in char-misc-next tree, and may have some conflict with this one. https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git/commit/?h=char-misc-next=c9d7e3da1f3c4cf5dddfc5d7ce4d76d013aba1cc fpga: dfl: afu: Corrected error handling levels I guess we need to rebase this patch on top of it? Moritz, do you have any suggestion? I'll send you a v2, rebased on top of the latest char-misc.git, no problem. thanks, -- John Hubbard NVIDIA
RE: [PATCH v2] fpga: dfl: afu: convert get_user_pages() --> pin_user_pages()
> >> Hi Moritz and FPGA developers, > >> > >> Is this OK? And if so, is it going into your git tree? Or should I > >> send it up through a different tree? (I'm new to the FPGA development > >> model). > > > > I can take it, sorry for sluggish response. > > > > That's great news, thanks Moritz! Sorry to be pushy, just didn't want it > to get lost. :) Thanks John for this patch, and thanks Moritz for taking care of this. Sorry for late response, one thing here we may need to be careful is a recent bug fixing patch, that fixing patch has been merged by Greg in char-misc-next tree, and may have some conflict with this one. https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git/commit/?h=char-misc-next=c9d7e3da1f3c4cf5dddfc5d7ce4d76d013aba1cc fpga: dfl: afu: Corrected error handling levels I guess we need to rebase this patch on top of it? Moritz, do you have any suggestion? Thanks Hao > > thanks, > -- > John Hubbard > NVIDIA
Re: [PATCH v2] fpga: dfl: afu: convert get_user_pages() --> pin_user_pages()
On 2020-05-23 13:57, Moritz Fischer wrote: On Fri, May 22, 2020 at 06:52:34PM -0700, John Hubbard wrote: On 2020-05-19 13:14, John Hubbard wrote: This code was using get_user_pages_fast(), in a "Case 2" scenario (DMA/RDMA), using the categorization from [1]. That means that it's time to convert the get_user_pages_fast() + put_page() calls to pin_user_pages_fast() + unpin_user_pages() calls. There is some helpful background in [2]: basically, this is a small part of fixing a long-standing disconnect between pinning pages, and file systems' use of those pages. [1] Documentation/core-api/pin_user_pages.rst [2] "Explicit pinning of user-space pages": https://lwn.net/Articles/807108/ Cc: Xu Yilun Cc: Wu Hao Cc: Moritz Fischer Cc: linux-f...@vger.kernel.org Signed-off-by: John Hubbard Hi Moritz and FPGA developers, Is this OK? And if so, is it going into your git tree? Or should I send it up through a different tree? (I'm new to the FPGA development model). I can take it, sorry for sluggish response. That's great news, thanks Moritz! Sorry to be pushy, just didn't want it to get lost. :) thanks, -- John Hubbard NVIDIA
Re: [PATCH v2] fpga: dfl: afu: convert get_user_pages() --> pin_user_pages()
On Fri, May 22, 2020 at 06:52:34PM -0700, John Hubbard wrote:
> On 2020-05-19 13:14, John Hubbard wrote:
> > This code was using get_user_pages_fast(), in a "Case 2" scenario
> > (DMA/RDMA), using the categorization from [1]. That means that it's
> > time to convert the get_user_pages_fast() + put_page() calls to
> > pin_user_pages_fast() + unpin_user_pages() calls.
> >
> > There is some helpful background in [2]: basically, this is a small
> > part of fixing a long-standing disconnect between pinning pages, and
> > file systems' use of those pages.
> >
> > [1] Documentation/core-api/pin_user_pages.rst
> >
> > [2] "Explicit pinning of user-space pages":
> > https://lwn.net/Articles/807108/
> >
> > Cc: Xu Yilun
> > Cc: Wu Hao
> > Cc: Moritz Fischer
> > Cc: linux-f...@vger.kernel.org
> > Signed-off-by: John Hubbard
>
>
> Hi Moritz and FPGA developers,
>
> Is this OK? And if so, is it going into your git tree? Or should I
> send it up through a different tree? (I'm new to the FPGA development
> model).
I can take it, sorry for sluggish response.
Cheers,
Moritz
>
>
> thanks,
> --
> John Hubbard
> NVIDIA
>
>
>
> > ---
> >
> > Hi,
> >
> > Changes since v1:
> >
> > Changed the label from "put_pages", to "unpin_pages".
> >
> > thanks,
> > John Hubbard
> > NVIDIA
> > drivers/fpga/dfl-afu-dma-region.c | 19 +--
> > 1 file changed, 5 insertions(+), 14 deletions(-)
> >
> > diff --git a/drivers/fpga/dfl-afu-dma-region.c
> > b/drivers/fpga/dfl-afu-dma-region.c
> > index 62f924489db5..a31dd3a7e581 100644
> > --- a/drivers/fpga/dfl-afu-dma-region.c
> > +++ b/drivers/fpga/dfl-afu-dma-region.c
> > @@ -16,15 +16,6 @@
> > #include "dfl-afu.h"
> > -static void put_all_pages(struct page **pages, int npages)
> > -{
> > - int i;
> > -
> > - for (i = 0; i < npages; i++)
> > - if (pages[i])
> > - put_page(pages[i]);
> > -}
> > -
> > void afu_dma_region_init(struct dfl_feature_platform_data *pdata)
> > {
> > struct dfl_afu *afu = dfl_fpga_pdata_get_private(pdata);
> > @@ -57,11 +48,11 @@ static int afu_dma_pin_pages(struct
> > dfl_feature_platform_data *pdata,
> > goto unlock_vm;
> > }
> > - pinned = get_user_pages_fast(region->user_addr, npages, FOLL_WRITE,
> > + pinned = pin_user_pages_fast(region->user_addr, npages, FOLL_WRITE,
> > region->pages);
> > if (pinned < 0) {
> > ret = pinned;
> > - goto put_pages;
> > + goto unpin_pages;
> > } else if (pinned != npages) {
> > ret = -EFAULT;
> > goto free_pages;
> > @@ -71,8 +62,8 @@ static int afu_dma_pin_pages(struct
> > dfl_feature_platform_data *pdata,
> > return 0;
> > -put_pages:
> > - put_all_pages(region->pages, pinned);
> > +unpin_pages:
> > + unpin_user_pages(region->pages, pinned);
> > free_pages:
> > kfree(region->pages);
> > unlock_vm:
> > @@ -94,7 +85,7 @@ static void afu_dma_unpin_pages(struct
> > dfl_feature_platform_data *pdata,
> > long npages = region->length >> PAGE_SHIFT;
> > struct device *dev = >dev->dev;
> > - put_all_pages(region->pages, npages);
> > + unpin_user_pages(region->pages, npages);
> > kfree(region->pages);
> > account_locked_vm(current->mm, npages, false);
> >
>
Re: [PATCH v2] fpga: dfl: afu: convert get_user_pages() --> pin_user_pages()
On 2020-05-19 13:14, John Hubbard wrote:
This code was using get_user_pages_fast(), in a "Case 2" scenario
(DMA/RDMA), using the categorization from [1]. That means that it's
time to convert the get_user_pages_fast() + put_page() calls to
pin_user_pages_fast() + unpin_user_pages() calls.
There is some helpful background in [2]: basically, this is a small
part of fixing a long-standing disconnect between pinning pages, and
file systems' use of those pages.
[1] Documentation/core-api/pin_user_pages.rst
[2] "Explicit pinning of user-space pages":
https://lwn.net/Articles/807108/
Cc: Xu Yilun
Cc: Wu Hao
Cc: Moritz Fischer
Cc: linux-f...@vger.kernel.org
Signed-off-by: John Hubbard
Hi Moritz and FPGA developers,
Is this OK? And if so, is it going into your git tree? Or should I
send it up through a different tree? (I'm new to the FPGA development
model).
thanks,
--
John Hubbard
NVIDIA
---
Hi,
Changes since v1:
Changed the label from "put_pages", to "unpin_pages".
thanks,
John Hubbard
NVIDIA
drivers/fpga/dfl-afu-dma-region.c | 19 +--
1 file changed, 5 insertions(+), 14 deletions(-)
diff --git a/drivers/fpga/dfl-afu-dma-region.c
b/drivers/fpga/dfl-afu-dma-region.c
index 62f924489db5..a31dd3a7e581 100644
--- a/drivers/fpga/dfl-afu-dma-region.c
+++ b/drivers/fpga/dfl-afu-dma-region.c
@@ -16,15 +16,6 @@
#include "dfl-afu.h"
-static void put_all_pages(struct page **pages, int npages)
-{
- int i;
-
- for (i = 0; i < npages; i++)
- if (pages[i])
- put_page(pages[i]);
-}
-
void afu_dma_region_init(struct dfl_feature_platform_data *pdata)
{
struct dfl_afu *afu = dfl_fpga_pdata_get_private(pdata);
@@ -57,11 +48,11 @@ static int afu_dma_pin_pages(struct
dfl_feature_platform_data *pdata,
goto unlock_vm;
}
- pinned = get_user_pages_fast(region->user_addr, npages, FOLL_WRITE,
+ pinned = pin_user_pages_fast(region->user_addr, npages, FOLL_WRITE,
region->pages);
if (pinned < 0) {
ret = pinned;
- goto put_pages;
+ goto unpin_pages;
} else if (pinned != npages) {
ret = -EFAULT;
goto free_pages;
@@ -71,8 +62,8 @@ static int afu_dma_pin_pages(struct dfl_feature_platform_data
*pdata,
return 0;
-put_pages:
- put_all_pages(region->pages, pinned);
+unpin_pages:
+ unpin_user_pages(region->pages, pinned);
free_pages:
kfree(region->pages);
unlock_vm:
@@ -94,7 +85,7 @@ static void afu_dma_unpin_pages(struct
dfl_feature_platform_data *pdata,
long npages = region->length >> PAGE_SHIFT;
struct device *dev = >dev->dev;
- put_all_pages(region->pages, npages);
+ unpin_user_pages(region->pages, npages);
kfree(region->pages);
account_locked_vm(current->mm, npages, false);
[PATCH v2] fpga: dfl: afu: convert get_user_pages() --> pin_user_pages()
This code was using get_user_pages_fast(), in a "Case 2" scenario
(DMA/RDMA), using the categorization from [1]. That means that it's
time to convert the get_user_pages_fast() + put_page() calls to
pin_user_pages_fast() + unpin_user_pages() calls.
There is some helpful background in [2]: basically, this is a small
part of fixing a long-standing disconnect between pinning pages, and
file systems' use of those pages.
[1] Documentation/core-api/pin_user_pages.rst
[2] "Explicit pinning of user-space pages":
https://lwn.net/Articles/807108/
Cc: Xu Yilun
Cc: Wu Hao
Cc: Moritz Fischer
Cc: linux-f...@vger.kernel.org
Signed-off-by: John Hubbard
---
Hi,
Changes since v1:
Changed the label from "put_pages", to "unpin_pages".
thanks,
John Hubbard
NVIDIA
drivers/fpga/dfl-afu-dma-region.c | 19 +--
1 file changed, 5 insertions(+), 14 deletions(-)
diff --git a/drivers/fpga/dfl-afu-dma-region.c
b/drivers/fpga/dfl-afu-dma-region.c
index 62f924489db5..a31dd3a7e581 100644
--- a/drivers/fpga/dfl-afu-dma-region.c
+++ b/drivers/fpga/dfl-afu-dma-region.c
@@ -16,15 +16,6 @@
#include "dfl-afu.h"
-static void put_all_pages(struct page **pages, int npages)
-{
- int i;
-
- for (i = 0; i < npages; i++)
- if (pages[i])
- put_page(pages[i]);
-}
-
void afu_dma_region_init(struct dfl_feature_platform_data *pdata)
{
struct dfl_afu *afu = dfl_fpga_pdata_get_private(pdata);
@@ -57,11 +48,11 @@ static int afu_dma_pin_pages(struct
dfl_feature_platform_data *pdata,
goto unlock_vm;
}
- pinned = get_user_pages_fast(region->user_addr, npages, FOLL_WRITE,
+ pinned = pin_user_pages_fast(region->user_addr, npages, FOLL_WRITE,
region->pages);
if (pinned < 0) {
ret = pinned;
- goto put_pages;
+ goto unpin_pages;
} else if (pinned != npages) {
ret = -EFAULT;
goto free_pages;
@@ -71,8 +62,8 @@ static int afu_dma_pin_pages(struct dfl_feature_platform_data
*pdata,
return 0;
-put_pages:
- put_all_pages(region->pages, pinned);
+unpin_pages:
+ unpin_user_pages(region->pages, pinned);
free_pages:
kfree(region->pages);
unlock_vm:
@@ -94,7 +85,7 @@ static void afu_dma_unpin_pages(struct
dfl_feature_platform_data *pdata,
long npages = region->length >> PAGE_SHIFT;
struct device *dev = >dev->dev;
- put_all_pages(region->pages, npages);
+ unpin_user_pages(region->pages, npages);
kfree(region->pages);
account_locked_vm(current->mm, npages, false);
--
2.26.2
