* [PATCH] vfio/type1: Fix vfio_find_dma_valid return
@ 2021-08-19 23:53 Anthony Yznaga
2021-08-20 16:24 ` Alex Williamson
0 siblings, 1 reply; 4+ messages in thread
From: Anthony Yznaga @ 2021-08-19 23:53 UTC (permalink / raw)
To: kvm; +Cc: alex.williamson, steven.sistare
Fix vfio_find_dma_valid to return WAITED on success if it was necessary
to wait which mean iommu lock was dropped and reacquired. This allows
vfio_iommu_type1_pin_pages to recheck vaddr_invalid_count and possibly
avoid the checking the validity of every vaddr in its list.
Signed-off-by: Anthony Yznaga <anthony.yznaga@oracle.com>
---
drivers/vfio/vfio_iommu_type1.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index a3e925a41b0d..7ca8c4e95da4 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -612,6 +612,7 @@ static int vfio_find_dma_valid(struct vfio_iommu *iommu, dma_addr_t start,
size_t size, struct vfio_dma **dma_p)
{
int ret;
+ int waited = 0;
do {
*dma_p = vfio_find_dma(iommu, start, size);
@@ -620,10 +621,10 @@ static int vfio_find_dma_valid(struct vfio_iommu *iommu, dma_addr_t start,
else if (!(*dma_p)->vaddr_invalid)
ret = 0;
else
- ret = vfio_wait(iommu);
+ ret = waited = vfio_wait(iommu);
} while (ret > 0);
- return ret;
+ return ret ? ret : waited;
}
/*
--
1.8.3.1
^ permalink raw reply related [flat|nested] 4+ messages in thread* Re: [PATCH] vfio/type1: Fix vfio_find_dma_valid return
2021-08-19 23:53 [PATCH] vfio/type1: Fix vfio_find_dma_valid return Anthony Yznaga
@ 2021-08-20 16:24 ` Alex Williamson
2021-08-20 18:44 ` Anthony Yznaga
0 siblings, 1 reply; 4+ messages in thread
From: Alex Williamson @ 2021-08-20 16:24 UTC (permalink / raw)
To: Anthony Yznaga; +Cc: kvm, steven.sistare
On Thu, 19 Aug 2021 16:53:57 -0700
Anthony Yznaga <anthony.yznaga@oracle.com> wrote:
> Fix vfio_find_dma_valid to return WAITED on success if it was necessary
> to wait which mean iommu lock was dropped and reacquired. This allows
> vfio_iommu_type1_pin_pages to recheck vaddr_invalid_count and possibly
> avoid the checking the validity of every vaddr in its list.
>
> Signed-off-by: Anthony Yznaga <anthony.yznaga@oracle.com>
> ---
> drivers/vfio/vfio_iommu_type1.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index a3e925a41b0d..7ca8c4e95da4 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -612,6 +612,7 @@ static int vfio_find_dma_valid(struct vfio_iommu *iommu, dma_addr_t start,
> size_t size, struct vfio_dma **dma_p)
> {
> int ret;
> + int waited = 0;
>
> do {
> *dma_p = vfio_find_dma(iommu, start, size);
> @@ -620,10 +621,10 @@ static int vfio_find_dma_valid(struct vfio_iommu *iommu, dma_addr_t start,
> else if (!(*dma_p)->vaddr_invalid)
> ret = 0;
> else
> - ret = vfio_wait(iommu);
> + ret = waited = vfio_wait(iommu);
> } while (ret > 0);
>
> - return ret;
> + return ret ? ret : waited;
> }
>
> /*
How about...
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 0b4f7c174c7a..0e9217687f5c 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -612,17 +612,17 @@ static int vfio_wait(struct vfio_iommu *iommu)
static int vfio_find_dma_valid(struct vfio_iommu *iommu, dma_addr_t start,
size_t size, struct vfio_dma **dma_p)
{
- int ret;
+ int ret = 0;
do {
*dma_p = vfio_find_dma(iommu, start, size);
if (!*dma_p)
- ret = -EINVAL;
+ return -EINVAL;
else if (!(*dma_p)->vaddr_invalid)
- ret = 0;
+ return ret;
else
ret = vfio_wait(iommu);
- } while (ret > 0);
+ } while (ret == WAITED);
return ret;
}
^ permalink raw reply related [flat|nested] 4+ messages in thread* Re: [PATCH] vfio/type1: Fix vfio_find_dma_valid return
2021-08-20 16:24 ` Alex Williamson
@ 2021-08-20 18:44 ` Anthony Yznaga
2021-08-20 19:46 ` Alex Williamson
0 siblings, 1 reply; 4+ messages in thread
From: Anthony Yznaga @ 2021-08-20 18:44 UTC (permalink / raw)
To: Alex Williamson; +Cc: kvm, steven.sistare
On 8/20/21 9:24 AM, Alex Williamson wrote:
> On Thu, 19 Aug 2021 16:53:57 -0700
> Anthony Yznaga <anthony.yznaga@oracle.com> wrote:
>
>> Fix vfio_find_dma_valid to return WAITED on success if it was necessary
>> to wait which mean iommu lock was dropped and reacquired. This allows
>> vfio_iommu_type1_pin_pages to recheck vaddr_invalid_count and possibly
>> avoid the checking the validity of every vaddr in its list.
>>
>> Signed-off-by: Anthony Yznaga <anthony.yznaga@oracle.com>
>> ---
>> drivers/vfio/vfio_iommu_type1.c | 5 +++--
>> 1 file changed, 3 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
>> index a3e925a41b0d..7ca8c4e95da4 100644
>> --- a/drivers/vfio/vfio_iommu_type1.c
>> +++ b/drivers/vfio/vfio_iommu_type1.c
>> @@ -612,6 +612,7 @@ static int vfio_find_dma_valid(struct vfio_iommu *iommu, dma_addr_t start,
>> size_t size, struct vfio_dma **dma_p)
>> {
>> int ret;
>> + int waited = 0;
>>
>> do {
>> *dma_p = vfio_find_dma(iommu, start, size);
>> @@ -620,10 +621,10 @@ static int vfio_find_dma_valid(struct vfio_iommu *iommu, dma_addr_t start,
>> else if (!(*dma_p)->vaddr_invalid)
>> ret = 0;
>> else
>> - ret = vfio_wait(iommu);
>> + ret = waited = vfio_wait(iommu);
>> } while (ret > 0);
>>
>> - return ret;
>> + return ret ? ret : waited;
>> }
>>
>> /*
> How about...
>
> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index 0b4f7c174c7a..0e9217687f5c 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -612,17 +612,17 @@ static int vfio_wait(struct vfio_iommu *iommu)
> static int vfio_find_dma_valid(struct vfio_iommu *iommu, dma_addr_t start,
> size_t size, struct vfio_dma **dma_p)
> {
> - int ret;
> + int ret = 0;
>
> do {
> *dma_p = vfio_find_dma(iommu, start, size);
> if (!*dma_p)
> - ret = -EINVAL;
> + return -EINVAL;
> else if (!(*dma_p)->vaddr_invalid)
> - ret = 0;
> + return ret;
> else
> ret = vfio_wait(iommu);
> - } while (ret > 0);
> + } while (ret == WAITED);
>
> return ret;
> }
>
Even better. Should I send a new patch?
Thanks,
Anthony
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH] vfio/type1: Fix vfio_find_dma_valid return
2021-08-20 18:44 ` Anthony Yznaga
@ 2021-08-20 19:46 ` Alex Williamson
0 siblings, 0 replies; 4+ messages in thread
From: Alex Williamson @ 2021-08-20 19:46 UTC (permalink / raw)
To: Anthony Yznaga; +Cc: kvm, steven.sistare
On Fri, 20 Aug 2021 11:44:01 -0700
Anthony Yznaga <anthony.yznaga@oracle.com> wrote:
> On 8/20/21 9:24 AM, Alex Williamson wrote:
> > On Thu, 19 Aug 2021 16:53:57 -0700
> > Anthony Yznaga <anthony.yznaga@oracle.com> wrote:
> >
> >> Fix vfio_find_dma_valid to return WAITED on success if it was necessary
> >> to wait which mean iommu lock was dropped and reacquired. This allows
> >> vfio_iommu_type1_pin_pages to recheck vaddr_invalid_count and possibly
> >> avoid the checking the validity of every vaddr in its list.
> >>
> >> Signed-off-by: Anthony Yznaga <anthony.yznaga@oracle.com>
> >> ---
> >> drivers/vfio/vfio_iommu_type1.c | 5 +++--
> >> 1 file changed, 3 insertions(+), 2 deletions(-)
> >>
> >> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> >> index a3e925a41b0d..7ca8c4e95da4 100644
> >> --- a/drivers/vfio/vfio_iommu_type1.c
> >> +++ b/drivers/vfio/vfio_iommu_type1.c
> >> @@ -612,6 +612,7 @@ static int vfio_find_dma_valid(struct vfio_iommu *iommu, dma_addr_t start,
> >> size_t size, struct vfio_dma **dma_p)
> >> {
> >> int ret;
> >> + int waited = 0;
> >>
> >> do {
> >> *dma_p = vfio_find_dma(iommu, start, size);
> >> @@ -620,10 +621,10 @@ static int vfio_find_dma_valid(struct vfio_iommu *iommu, dma_addr_t start,
> >> else if (!(*dma_p)->vaddr_invalid)
> >> ret = 0;
> >> else
> >> - ret = vfio_wait(iommu);
> >> + ret = waited = vfio_wait(iommu);
> >> } while (ret > 0);
> >>
> >> - return ret;
> >> + return ret ? ret : waited;
> >> }
> >>
> >> /*
> > How about...
> >
> > diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> > index 0b4f7c174c7a..0e9217687f5c 100644
> > --- a/drivers/vfio/vfio_iommu_type1.c
> > +++ b/drivers/vfio/vfio_iommu_type1.c
> > @@ -612,17 +612,17 @@ static int vfio_wait(struct vfio_iommu *iommu)
> > static int vfio_find_dma_valid(struct vfio_iommu *iommu, dma_addr_t start,
> > size_t size, struct vfio_dma **dma_p)
> > {
> > - int ret;
> > + int ret = 0;
> >
> > do {
> > *dma_p = vfio_find_dma(iommu, start, size);
> > if (!*dma_p)
> > - ret = -EINVAL;
> > + return -EINVAL;
> > else if (!(*dma_p)->vaddr_invalid)
> > - ret = 0;
> > + return ret;
> > else
> > ret = vfio_wait(iommu);
> > - } while (ret > 0);
> > + } while (ret == WAITED);
> >
> > return ret;
> > }
> >
>
> Even better. Should I send a new patch?
That would be preferable, otherwise at least a sign-off or reviewed-by
for the newer version. Thanks,
Alex
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2021-08-20 19:46 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-08-19 23:53 [PATCH] vfio/type1: Fix vfio_find_dma_valid return Anthony Yznaga
2021-08-20 16:24 ` Alex Williamson
2021-08-20 18:44 ` Anthony Yznaga
2021-08-20 19:46 ` Alex Williamson
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.