2019-09-16 22:41:10

by Denis Efremov (Oracle)

[permalink] [raw]
Subject: [PATCH v3 17/26] vfio_pci: Loop using PCI_STD_NUM_BARS

Refactor loops to use idiomatic C style and avoid the fencepost error
of using "i < PCI_STD_RESOURCE_END" when "i <= PCI_STD_RESOURCE_END"
is required, e.g., commit 2f686f1d9bee ("PCI: Correct PCI_STD_RESOURCE_END
usage").

To iterate through all possible BARs, loop conditions changed to the
*number* of BARs "i < PCI_STD_NUM_BARS", instead of the index of the last
valid BAR "i <= PCI_STD_RESOURCE_END".

Cc: Cornelia Huck <[email protected]>
Cc: Alex Williamson <[email protected]>
Signed-off-by: Denis Efremov <[email protected]>
---
drivers/vfio/pci/vfio_pci.c | 11 ++++++----
drivers/vfio/pci/vfio_pci_config.c | 32 +++++++++++++++--------------
drivers/vfio/pci/vfio_pci_private.h | 4 ++--
3 files changed, 26 insertions(+), 21 deletions(-)

diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
index 703948c9fbe1..cb7d220d3246 100644
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -110,13 +110,15 @@ static inline bool vfio_pci_is_vga(struct pci_dev *pdev)
static void vfio_pci_probe_mmaps(struct vfio_pci_device *vdev)
{
struct resource *res;
- int bar;
+ int i;
struct vfio_pci_dummy_resource *dummy_res;

INIT_LIST_HEAD(&vdev->dummy_resources_list);

- for (bar = PCI_STD_RESOURCES; bar <= PCI_STD_RESOURCE_END; bar++) {
- res = vdev->pdev->resource + bar;
+ for (i = 0; i < PCI_STD_NUM_BARS; i++) {
+ int bar = i + PCI_STD_RESOURCES;
+
+ res = &vdev->pdev->resource[bar];

if (!IS_ENABLED(CONFIG_VFIO_PCI_MMAP))
goto no_mmap;
@@ -399,7 +401,8 @@ static void vfio_pci_disable(struct vfio_pci_device *vdev)

vfio_config_free(vdev);

- for (bar = PCI_STD_RESOURCES; bar <= PCI_STD_RESOURCE_END; bar++) {
+ for (i = 0; i < PCI_STD_NUM_BARS; i++) {
+ bar = i + PCI_STD_RESOURCES;
if (!vdev->barmap[bar])
continue;
pci_iounmap(pdev, vdev->barmap[bar]);
diff --git a/drivers/vfio/pci/vfio_pci_config.c b/drivers/vfio/pci/vfio_pci_config.c
index f0891bd8444c..90c0b80f8acf 100644
--- a/drivers/vfio/pci/vfio_pci_config.c
+++ b/drivers/vfio/pci/vfio_pci_config.c
@@ -450,30 +450,32 @@ static void vfio_bar_fixup(struct vfio_pci_device *vdev)
{
struct pci_dev *pdev = vdev->pdev;
int i;
- __le32 *bar;
+ __le32 *vbar;
u64 mask;

- bar = (__le32 *)&vdev->vconfig[PCI_BASE_ADDRESS_0];
+ vbar = (__le32 *)&vdev->vconfig[PCI_BASE_ADDRESS_0];

- for (i = PCI_STD_RESOURCES; i <= PCI_STD_RESOURCE_END; i++, bar++) {
- if (!pci_resource_start(pdev, i)) {
- *bar = 0; /* Unmapped by host = unimplemented to user */
+ for (i = 0; i < PCI_STD_NUM_BARS; i++, vbar++) {
+ int bar = i + PCI_STD_RESOURCES;
+
+ if (!pci_resource_start(pdev, bar)) {
+ *vbar = 0; /* Unmapped by host = unimplemented to user */
continue;
}

- mask = ~(pci_resource_len(pdev, i) - 1);
+ mask = ~(pci_resource_len(pdev, bar) - 1);

- *bar &= cpu_to_le32((u32)mask);
- *bar |= vfio_generate_bar_flags(pdev, i);
+ *vbar &= cpu_to_le32((u32)mask);
+ *vbar |= vfio_generate_bar_flags(pdev, bar);

- if (*bar & cpu_to_le32(PCI_BASE_ADDRESS_MEM_TYPE_64)) {
- bar++;
- *bar &= cpu_to_le32((u32)(mask >> 32));
+ if (*vbar & cpu_to_le32(PCI_BASE_ADDRESS_MEM_TYPE_64)) {
+ vbar++;
+ *vbar &= cpu_to_le32((u32)(mask >> 32));
i++;
}
}

- bar = (__le32 *)&vdev->vconfig[PCI_ROM_ADDRESS];
+ vbar = (__le32 *)&vdev->vconfig[PCI_ROM_ADDRESS];

/*
* NB. REGION_INFO will have reported zero size if we weren't able
@@ -483,14 +485,14 @@ static void vfio_bar_fixup(struct vfio_pci_device *vdev)
if (pci_resource_start(pdev, PCI_ROM_RESOURCE)) {
mask = ~(pci_resource_len(pdev, PCI_ROM_RESOURCE) - 1);
mask |= PCI_ROM_ADDRESS_ENABLE;
- *bar &= cpu_to_le32((u32)mask);
+ *vbar &= cpu_to_le32((u32)mask);
} else if (pdev->resource[PCI_ROM_RESOURCE].flags &
IORESOURCE_ROM_SHADOW) {
mask = ~(0x20000 - 1);
mask |= PCI_ROM_ADDRESS_ENABLE;
- *bar &= cpu_to_le32((u32)mask);
+ *vbar &= cpu_to_le32((u32)mask);
} else
- *bar = 0;
+ *vbar = 0;

vdev->bardirty = false;
}
diff --git a/drivers/vfio/pci/vfio_pci_private.h b/drivers/vfio/pci/vfio_pci_private.h
index ee6ee91718a4..8a2c7607d513 100644
--- a/drivers/vfio/pci/vfio_pci_private.h
+++ b/drivers/vfio/pci/vfio_pci_private.h
@@ -86,8 +86,8 @@ struct vfio_pci_reflck {

struct vfio_pci_device {
struct pci_dev *pdev;
- void __iomem *barmap[PCI_STD_RESOURCE_END + 1];
- bool bar_mmap_supported[PCI_STD_RESOURCE_END + 1];
+ void __iomem *barmap[PCI_STD_NUM_BARS];
+ bool bar_mmap_supported[PCI_STD_NUM_BARS];
u8 *pci_config_map;
u8 *vconfig;
struct perm_bits *msi_perm;
--
2.21.0


2019-09-18 09:42:03

by Andrew Murray

[permalink] [raw]
Subject: Re: [PATCH v3 17/26] vfio_pci: Loop using PCI_STD_NUM_BARS

On Mon, Sep 16, 2019 at 11:41:49PM +0300, Denis Efremov wrote:
> Refactor loops to use idiomatic C style and avoid the fencepost error
> of using "i < PCI_STD_RESOURCE_END" when "i <= PCI_STD_RESOURCE_END"
> is required, e.g., commit 2f686f1d9bee ("PCI: Correct PCI_STD_RESOURCE_END
> usage").
>
> To iterate through all possible BARs, loop conditions changed to the
> *number* of BARs "i < PCI_STD_NUM_BARS", instead of the index of the last
> valid BAR "i <= PCI_STD_RESOURCE_END".
>
> Cc: Cornelia Huck <[email protected]>
> Cc: Alex Williamson <[email protected]>
> Signed-off-by: Denis Efremov <[email protected]>
> ---
> drivers/vfio/pci/vfio_pci.c | 11 ++++++----
> drivers/vfio/pci/vfio_pci_config.c | 32 +++++++++++++++--------------
> drivers/vfio/pci/vfio_pci_private.h | 4 ++--
> 3 files changed, 26 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
> index 703948c9fbe1..cb7d220d3246 100644
> --- a/drivers/vfio/pci/vfio_pci.c
> +++ b/drivers/vfio/pci/vfio_pci.c
> @@ -110,13 +110,15 @@ static inline bool vfio_pci_is_vga(struct pci_dev *pdev)
> static void vfio_pci_probe_mmaps(struct vfio_pci_device *vdev)
> {
> struct resource *res;
> - int bar;
> + int i;
> struct vfio_pci_dummy_resource *dummy_res;
>
> INIT_LIST_HEAD(&vdev->dummy_resources_list);
>
> - for (bar = PCI_STD_RESOURCES; bar <= PCI_STD_RESOURCE_END; bar++) {
> - res = vdev->pdev->resource + bar;
> + for (i = 0; i < PCI_STD_NUM_BARS; i++) {
> + int bar = i + PCI_STD_RESOURCES;
> +
> + res = &vdev->pdev->resource[bar];

Why can't we just drop PCI_STD_RESOURCES and replace it was 0. I understand
the abstraction here, but we don't do it elsewhere across the kernel. Is this
necessary?

Thanks,

Andrew Murray

>
> if (!IS_ENABLED(CONFIG_VFIO_PCI_MMAP))
> goto no_mmap;
> @@ -399,7 +401,8 @@ static void vfio_pci_disable(struct vfio_pci_device *vdev)
>
> vfio_config_free(vdev);
>
> - for (bar = PCI_STD_RESOURCES; bar <= PCI_STD_RESOURCE_END; bar++) {
> + for (i = 0; i < PCI_STD_NUM_BARS; i++) {
> + bar = i + PCI_STD_RESOURCES;
> if (!vdev->barmap[bar])
> continue;
> pci_iounmap(pdev, vdev->barmap[bar]);
> diff --git a/drivers/vfio/pci/vfio_pci_config.c b/drivers/vfio/pci/vfio_pci_config.c
> index f0891bd8444c..90c0b80f8acf 100644
> --- a/drivers/vfio/pci/vfio_pci_config.c
> +++ b/drivers/vfio/pci/vfio_pci_config.c
> @@ -450,30 +450,32 @@ static void vfio_bar_fixup(struct vfio_pci_device *vdev)
> {
> struct pci_dev *pdev = vdev->pdev;
> int i;
> - __le32 *bar;
> + __le32 *vbar;
> u64 mask;
>
> - bar = (__le32 *)&vdev->vconfig[PCI_BASE_ADDRESS_0];
> + vbar = (__le32 *)&vdev->vconfig[PCI_BASE_ADDRESS_0];
>
> - for (i = PCI_STD_RESOURCES; i <= PCI_STD_RESOURCE_END; i++, bar++) {
> - if (!pci_resource_start(pdev, i)) {
> - *bar = 0; /* Unmapped by host = unimplemented to user */
> + for (i = 0; i < PCI_STD_NUM_BARS; i++, vbar++) {
> + int bar = i + PCI_STD_RESOURCES;
> +
> + if (!pci_resource_start(pdev, bar)) {
> + *vbar = 0; /* Unmapped by host = unimplemented to user */
> continue;
> }
>
> - mask = ~(pci_resource_len(pdev, i) - 1);
> + mask = ~(pci_resource_len(pdev, bar) - 1);
>
> - *bar &= cpu_to_le32((u32)mask);
> - *bar |= vfio_generate_bar_flags(pdev, i);
> + *vbar &= cpu_to_le32((u32)mask);
> + *vbar |= vfio_generate_bar_flags(pdev, bar);
>
> - if (*bar & cpu_to_le32(PCI_BASE_ADDRESS_MEM_TYPE_64)) {
> - bar++;
> - *bar &= cpu_to_le32((u32)(mask >> 32));
> + if (*vbar & cpu_to_le32(PCI_BASE_ADDRESS_MEM_TYPE_64)) {
> + vbar++;
> + *vbar &= cpu_to_le32((u32)(mask >> 32));
> i++;
> }
> }
>
> - bar = (__le32 *)&vdev->vconfig[PCI_ROM_ADDRESS];
> + vbar = (__le32 *)&vdev->vconfig[PCI_ROM_ADDRESS];
>
> /*
> * NB. REGION_INFO will have reported zero size if we weren't able
> @@ -483,14 +485,14 @@ static void vfio_bar_fixup(struct vfio_pci_device *vdev)
> if (pci_resource_start(pdev, PCI_ROM_RESOURCE)) {
> mask = ~(pci_resource_len(pdev, PCI_ROM_RESOURCE) - 1);
> mask |= PCI_ROM_ADDRESS_ENABLE;
> - *bar &= cpu_to_le32((u32)mask);
> + *vbar &= cpu_to_le32((u32)mask);
> } else if (pdev->resource[PCI_ROM_RESOURCE].flags &
> IORESOURCE_ROM_SHADOW) {
> mask = ~(0x20000 - 1);
> mask |= PCI_ROM_ADDRESS_ENABLE;
> - *bar &= cpu_to_le32((u32)mask);
> + *vbar &= cpu_to_le32((u32)mask);
> } else
> - *bar = 0;
> + *vbar = 0;
>
> vdev->bardirty = false;
> }
> diff --git a/drivers/vfio/pci/vfio_pci_private.h b/drivers/vfio/pci/vfio_pci_private.h
> index ee6ee91718a4..8a2c7607d513 100644
> --- a/drivers/vfio/pci/vfio_pci_private.h
> +++ b/drivers/vfio/pci/vfio_pci_private.h
> @@ -86,8 +86,8 @@ struct vfio_pci_reflck {
>
> struct vfio_pci_device {
> struct pci_dev *pdev;
> - void __iomem *barmap[PCI_STD_RESOURCE_END + 1];
> - bool bar_mmap_supported[PCI_STD_RESOURCE_END + 1];
> + void __iomem *barmap[PCI_STD_NUM_BARS];
> + bool bar_mmap_supported[PCI_STD_NUM_BARS];
> u8 *pci_config_map;
> u8 *vconfig;
> struct perm_bits *msi_perm;
> --
> 2.21.0
>

2019-09-18 14:34:08

by Denis Efremov (Oracle)

[permalink] [raw]
Subject: Re: [PATCH v3 17/26] vfio_pci: Loop using PCI_STD_NUM_BARS

On 9/18/19 12:17 PM, Andrew Murray wrote:
> On Mon, Sep 16, 2019 at 11:41:49PM +0300, Denis Efremov wrote:
>> Refactor loops to use idiomatic C style and avoid the fencepost error
>> of using "i < PCI_STD_RESOURCE_END" when "i <= PCI_STD_RESOURCE_END"
>> is required, e.g., commit 2f686f1d9bee ("PCI: Correct PCI_STD_RESOURCE_END
>> usage").
>>
>> To iterate through all possible BARs, loop conditions changed to the
>> *number* of BARs "i < PCI_STD_NUM_BARS", instead of the index of the last
>> valid BAR "i <= PCI_STD_RESOURCE_END".
>>
>> Cc: Cornelia Huck <[email protected]>
>> Cc: Alex Williamson <[email protected]>
>> Signed-off-by: Denis Efremov <[email protected]>
>> ---
>> drivers/vfio/pci/vfio_pci.c | 11 ++++++----
>> drivers/vfio/pci/vfio_pci_config.c | 32 +++++++++++++++--------------
>> drivers/vfio/pci/vfio_pci_private.h | 4 ++--
>> 3 files changed, 26 insertions(+), 21 deletions(-)
>>
>> diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
>> index 703948c9fbe1..cb7d220d3246 100644
>> --- a/drivers/vfio/pci/vfio_pci.c
>> +++ b/drivers/vfio/pci/vfio_pci.c
>> @@ -110,13 +110,15 @@ static inline bool vfio_pci_is_vga(struct pci_dev *pdev)
>> static void vfio_pci_probe_mmaps(struct vfio_pci_device *vdev)
>> {
>> struct resource *res;
>> - int bar;
>> + int i;
>> struct vfio_pci_dummy_resource *dummy_res;
>>
>> INIT_LIST_HEAD(&vdev->dummy_resources_list);
>>
>> - for (bar = PCI_STD_RESOURCES; bar <= PCI_STD_RESOURCE_END; bar++) {
>> - res = vdev->pdev->resource + bar;
>> + for (i = 0; i < PCI_STD_NUM_BARS; i++) {
>> + int bar = i + PCI_STD_RESOURCES;
>> +
>> + res = &vdev->pdev->resource[bar];
>
> Why can't we just drop PCI_STD_RESOURCES and replace it was 0. I understand
> the abstraction here, but we don't do it elsewhere across the kernel. Is this
> necessary?

There was a discussion about this particular case:
https://lkml.org/lkml/2019/8/12/999

It was decided to save the original style for vfio drivers.

>
> Thanks,
>
> Andrew Murray
>
>>
>> if (!IS_ENABLED(CONFIG_VFIO_PCI_MMAP))
>> goto no_mmap;
>> @@ -399,7 +401,8 @@ static void vfio_pci_disable(struct vfio_pci_device *vdev)
>>
>> vfio_config_free(vdev);
>>
>> - for (bar = PCI_STD_RESOURCES; bar <= PCI_STD_RESOURCE_END; bar++) {
>> + for (i = 0; i < PCI_STD_NUM_BARS; i++) {
>> + bar = i + PCI_STD_RESOURCES;
>> if (!vdev->barmap[bar])
>> continue;
>> pci_iounmap(pdev, vdev->barmap[bar]);
>> diff --git a/drivers/vfio/pci/vfio_pci_config.c b/drivers/vfio/pci/vfio_pci_config.c
>> index f0891bd8444c..90c0b80f8acf 100644
>> --- a/drivers/vfio/pci/vfio_pci_config.c
>> +++ b/drivers/vfio/pci/vfio_pci_config.c
>> @@ -450,30 +450,32 @@ static void vfio_bar_fixup(struct vfio_pci_device *vdev)
>> {
>> struct pci_dev *pdev = vdev->pdev;
>> int i;
>> - __le32 *bar;
>> + __le32 *vbar;
>> u64 mask;
>>
>> - bar = (__le32 *)&vdev->vconfig[PCI_BASE_ADDRESS_0];
>> + vbar = (__le32 *)&vdev->vconfig[PCI_BASE_ADDRESS_0];
>>
>> - for (i = PCI_STD_RESOURCES; i <= PCI_STD_RESOURCE_END; i++, bar++) {
>> - if (!pci_resource_start(pdev, i)) {
>> - *bar = 0; /* Unmapped by host = unimplemented to user */
>> + for (i = 0; i < PCI_STD_NUM_BARS; i++, vbar++) {
>> + int bar = i + PCI_STD_RESOURCES;
>> +
>> + if (!pci_resource_start(pdev, bar)) {
>> + *vbar = 0; /* Unmapped by host = unimplemented to user */
>> continue;
>> }
>>
>> - mask = ~(pci_resource_len(pdev, i) - 1);
>> + mask = ~(pci_resource_len(pdev, bar) - 1);
>>
>> - *bar &= cpu_to_le32((u32)mask);
>> - *bar |= vfio_generate_bar_flags(pdev, i);
>> + *vbar &= cpu_to_le32((u32)mask);
>> + *vbar |= vfio_generate_bar_flags(pdev, bar);
>>
>> - if (*bar & cpu_to_le32(PCI_BASE_ADDRESS_MEM_TYPE_64)) {
>> - bar++;
>> - *bar &= cpu_to_le32((u32)(mask >> 32));
>> + if (*vbar & cpu_to_le32(PCI_BASE_ADDRESS_MEM_TYPE_64)) {
>> + vbar++;
>> + *vbar &= cpu_to_le32((u32)(mask >> 32));
>> i++;
>> }
>> }
>>
>> - bar = (__le32 *)&vdev->vconfig[PCI_ROM_ADDRESS];
>> + vbar = (__le32 *)&vdev->vconfig[PCI_ROM_ADDRESS];
>>
>> /*
>> * NB. REGION_INFO will have reported zero size if we weren't able
>> @@ -483,14 +485,14 @@ static void vfio_bar_fixup(struct vfio_pci_device *vdev)
>> if (pci_resource_start(pdev, PCI_ROM_RESOURCE)) {
>> mask = ~(pci_resource_len(pdev, PCI_ROM_RESOURCE) - 1);
>> mask |= PCI_ROM_ADDRESS_ENABLE;
>> - *bar &= cpu_to_le32((u32)mask);
>> + *vbar &= cpu_to_le32((u32)mask);
>> } else if (pdev->resource[PCI_ROM_RESOURCE].flags &
>> IORESOURCE_ROM_SHADOW) {
>> mask = ~(0x20000 - 1);
>> mask |= PCI_ROM_ADDRESS_ENABLE;
>> - *bar &= cpu_to_le32((u32)mask);
>> + *vbar &= cpu_to_le32((u32)mask);
>> } else
>> - *bar = 0;
>> + *vbar = 0;
>>
>> vdev->bardirty = false;
>> }
>> diff --git a/drivers/vfio/pci/vfio_pci_private.h b/drivers/vfio/pci/vfio_pci_private.h
>> index ee6ee91718a4..8a2c7607d513 100644
>> --- a/drivers/vfio/pci/vfio_pci_private.h
>> +++ b/drivers/vfio/pci/vfio_pci_private.h
>> @@ -86,8 +86,8 @@ struct vfio_pci_reflck {
>>
>> struct vfio_pci_device {
>> struct pci_dev *pdev;
>> - void __iomem *barmap[PCI_STD_RESOURCE_END + 1];
>> - bool bar_mmap_supported[PCI_STD_RESOURCE_END + 1];
>> + void __iomem *barmap[PCI_STD_NUM_BARS];
>> + bool bar_mmap_supported[PCI_STD_NUM_BARS];
>> u8 *pci_config_map;
>> u8 *vconfig;
>> struct perm_bits *msi_perm;
>> --
>> 2.21.0
>>

2019-09-19 08:04:21

by Andrew Murray

[permalink] [raw]
Subject: Re: [PATCH v3 17/26] vfio_pci: Loop using PCI_STD_NUM_BARS

On Wed, Sep 18, 2019 at 05:31:33PM +0300, Denis Efremov wrote:
> On 9/18/19 12:17 PM, Andrew Murray wrote:
> > On Mon, Sep 16, 2019 at 11:41:49PM +0300, Denis Efremov wrote:
> >> Refactor loops to use idiomatic C style and avoid the fencepost error
> >> of using "i < PCI_STD_RESOURCE_END" when "i <= PCI_STD_RESOURCE_END"
> >> is required, e.g., commit 2f686f1d9bee ("PCI: Correct PCI_STD_RESOURCE_END
> >> usage").
> >>
> >> To iterate through all possible BARs, loop conditions changed to the
> >> *number* of BARs "i < PCI_STD_NUM_BARS", instead of the index of the last
> >> valid BAR "i <= PCI_STD_RESOURCE_END".
> >>
> >> Cc: Cornelia Huck <[email protected]>
> >> Cc: Alex Williamson <[email protected]>
> >> Signed-off-by: Denis Efremov <[email protected]>
> >> ---
> >> drivers/vfio/pci/vfio_pci.c | 11 ++++++----
> >> drivers/vfio/pci/vfio_pci_config.c | 32 +++++++++++++++--------------
> >> drivers/vfio/pci/vfio_pci_private.h | 4 ++--
> >> 3 files changed, 26 insertions(+), 21 deletions(-)
> >>
> >> diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
> >> index 703948c9fbe1..cb7d220d3246 100644
> >> --- a/drivers/vfio/pci/vfio_pci.c
> >> +++ b/drivers/vfio/pci/vfio_pci.c
> >> @@ -110,13 +110,15 @@ static inline bool vfio_pci_is_vga(struct pci_dev *pdev)
> >> static void vfio_pci_probe_mmaps(struct vfio_pci_device *vdev)
> >> {
> >> struct resource *res;
> >> - int bar;
> >> + int i;
> >> struct vfio_pci_dummy_resource *dummy_res;
> >>
> >> INIT_LIST_HEAD(&vdev->dummy_resources_list);
> >>
> >> - for (bar = PCI_STD_RESOURCES; bar <= PCI_STD_RESOURCE_END; bar++) {
> >> - res = vdev->pdev->resource + bar;
> >> + for (i = 0; i < PCI_STD_NUM_BARS; i++) {
> >> + int bar = i + PCI_STD_RESOURCES;
> >> +
> >> + res = &vdev->pdev->resource[bar];
> >
> > Why can't we just drop PCI_STD_RESOURCES and replace it was 0. I understand
> > the abstraction here, but we don't do it elsewhere across the kernel. Is this
> > necessary?
>
> There was a discussion about this particular case:
> https://lkml.org/lkml/2019/8/12/999
>
> It was decided to save the original style for vfio drivers.

OK no problem.

Thanks,

Andrew Murray

>
> >
> > Thanks,
> >
> > Andrew Murray
> >
> >>
> >> if (!IS_ENABLED(CONFIG_VFIO_PCI_MMAP))
> >> goto no_mmap;
> >> @@ -399,7 +401,8 @@ static void vfio_pci_disable(struct vfio_pci_device *vdev)
> >>
> >> vfio_config_free(vdev);
> >>
> >> - for (bar = PCI_STD_RESOURCES; bar <= PCI_STD_RESOURCE_END; bar++) {
> >> + for (i = 0; i < PCI_STD_NUM_BARS; i++) {
> >> + bar = i + PCI_STD_RESOURCES;
> >> if (!vdev->barmap[bar])
> >> continue;
> >> pci_iounmap(pdev, vdev->barmap[bar]);
> >> diff --git a/drivers/vfio/pci/vfio_pci_config.c b/drivers/vfio/pci/vfio_pci_config.c
> >> index f0891bd8444c..90c0b80f8acf 100644
> >> --- a/drivers/vfio/pci/vfio_pci_config.c
> >> +++ b/drivers/vfio/pci/vfio_pci_config.c
> >> @@ -450,30 +450,32 @@ static void vfio_bar_fixup(struct vfio_pci_device *vdev)
> >> {
> >> struct pci_dev *pdev = vdev->pdev;
> >> int i;
> >> - __le32 *bar;
> >> + __le32 *vbar;
> >> u64 mask;
> >>
> >> - bar = (__le32 *)&vdev->vconfig[PCI_BASE_ADDRESS_0];
> >> + vbar = (__le32 *)&vdev->vconfig[PCI_BASE_ADDRESS_0];
> >>
> >> - for (i = PCI_STD_RESOURCES; i <= PCI_STD_RESOURCE_END; i++, bar++) {
> >> - if (!pci_resource_start(pdev, i)) {
> >> - *bar = 0; /* Unmapped by host = unimplemented to user */
> >> + for (i = 0; i < PCI_STD_NUM_BARS; i++, vbar++) {
> >> + int bar = i + PCI_STD_RESOURCES;
> >> +
> >> + if (!pci_resource_start(pdev, bar)) {
> >> + *vbar = 0; /* Unmapped by host = unimplemented to user */
> >> continue;
> >> }
> >>
> >> - mask = ~(pci_resource_len(pdev, i) - 1);
> >> + mask = ~(pci_resource_len(pdev, bar) - 1);
> >>
> >> - *bar &= cpu_to_le32((u32)mask);
> >> - *bar |= vfio_generate_bar_flags(pdev, i);
> >> + *vbar &= cpu_to_le32((u32)mask);
> >> + *vbar |= vfio_generate_bar_flags(pdev, bar);
> >>
> >> - if (*bar & cpu_to_le32(PCI_BASE_ADDRESS_MEM_TYPE_64)) {
> >> - bar++;
> >> - *bar &= cpu_to_le32((u32)(mask >> 32));
> >> + if (*vbar & cpu_to_le32(PCI_BASE_ADDRESS_MEM_TYPE_64)) {
> >> + vbar++;
> >> + *vbar &= cpu_to_le32((u32)(mask >> 32));
> >> i++;
> >> }
> >> }
> >>
> >> - bar = (__le32 *)&vdev->vconfig[PCI_ROM_ADDRESS];
> >> + vbar = (__le32 *)&vdev->vconfig[PCI_ROM_ADDRESS];
> >>
> >> /*
> >> * NB. REGION_INFO will have reported zero size if we weren't able
> >> @@ -483,14 +485,14 @@ static void vfio_bar_fixup(struct vfio_pci_device *vdev)
> >> if (pci_resource_start(pdev, PCI_ROM_RESOURCE)) {
> >> mask = ~(pci_resource_len(pdev, PCI_ROM_RESOURCE) - 1);
> >> mask |= PCI_ROM_ADDRESS_ENABLE;
> >> - *bar &= cpu_to_le32((u32)mask);
> >> + *vbar &= cpu_to_le32((u32)mask);
> >> } else if (pdev->resource[PCI_ROM_RESOURCE].flags &
> >> IORESOURCE_ROM_SHADOW) {
> >> mask = ~(0x20000 - 1);
> >> mask |= PCI_ROM_ADDRESS_ENABLE;
> >> - *bar &= cpu_to_le32((u32)mask);
> >> + *vbar &= cpu_to_le32((u32)mask);
> >> } else
> >> - *bar = 0;
> >> + *vbar = 0;
> >>
> >> vdev->bardirty = false;
> >> }
> >> diff --git a/drivers/vfio/pci/vfio_pci_private.h b/drivers/vfio/pci/vfio_pci_private.h
> >> index ee6ee91718a4..8a2c7607d513 100644
> >> --- a/drivers/vfio/pci/vfio_pci_private.h
> >> +++ b/drivers/vfio/pci/vfio_pci_private.h
> >> @@ -86,8 +86,8 @@ struct vfio_pci_reflck {
> >>
> >> struct vfio_pci_device {
> >> struct pci_dev *pdev;
> >> - void __iomem *barmap[PCI_STD_RESOURCE_END + 1];
> >> - bool bar_mmap_supported[PCI_STD_RESOURCE_END + 1];
> >> + void __iomem *barmap[PCI_STD_NUM_BARS];
> >> + bool bar_mmap_supported[PCI_STD_NUM_BARS];
> >> u8 *pci_config_map;
> >> u8 *vconfig;
> >> struct perm_bits *msi_perm;
> >> --
> >> 2.21.0
> >>
>