diff mbox series

[v3,04/26] PCI: endpoint: Use PCI_STD_NUM_BARS

Message ID 20190916204158.6889-5-efremov@linux.com (mailing list archive)
State New, archived
Delegated to: Bjorn Helgaas
Headers show
Series [RESEND,v3,01/26] PCI: Add define for the number of standard PCI BARs | expand

Commit Message

Denis Efremov (Oracle) Sept. 16, 2019, 8:41 p.m. UTC
To iterate through all possible BARs, loop conditions refactored to the
*number* of BARs "i < PCI_STD_NUM_BARS", instead of the index of the last
valid BAR "i <= BAR_5". This is more idiomatic C style and allows to avoid
the fencepost error. Array definitions changed to PCI_STD_NUM_BARS where
appropriate.

Cc: Kishon Vijay Abraham I <kishon@ti.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Denis Efremov <efremov@linux.com>
---
 drivers/pci/endpoint/functions/pci-epf-test.c | 10 +++++-----
 include/linux/pci-epc.h                       |  2 +-
 2 files changed, 6 insertions(+), 6 deletions(-)

Comments

Andrew Murray Sept. 18, 2019, 9:19 a.m. UTC | #1
On Mon, Sep 16, 2019 at 11:41:36PM +0300, Denis Efremov wrote:
> To iterate through all possible BARs, loop conditions refactored to the
> *number* of BARs "i < PCI_STD_NUM_BARS", instead of the index of the last
> valid BAR "i <= BAR_5". This is more idiomatic C style and allows to avoid
> the fencepost error. Array definitions changed to PCI_STD_NUM_BARS where
> appropriate.
> 
> Cc: Kishon Vijay Abraham I <kishon@ti.com>
> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
> Signed-off-by: Denis Efremov <efremov@linux.com>
> ---
>  drivers/pci/endpoint/functions/pci-epf-test.c | 10 +++++-----
>  include/linux/pci-epc.h                       |  2 +-
>  2 files changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c
> index 1cfe3687a211..5d74f81ddfe4 100644
> --- a/drivers/pci/endpoint/functions/pci-epf-test.c
> +++ b/drivers/pci/endpoint/functions/pci-epf-test.c
> @@ -44,7 +44,7 @@
>  static struct workqueue_struct *kpcitest_workqueue;
>  
>  struct pci_epf_test {
> -	void			*reg[6];
> +	void			*reg[PCI_STD_NUM_BARS];
>  	struct pci_epf		*epf;
>  	enum pci_barno		test_reg_bar;
>  	struct delayed_work	cmd_handler;
> @@ -377,7 +377,7 @@ static void pci_epf_test_unbind(struct pci_epf *epf)
>  
>  	cancel_delayed_work(&epf_test->cmd_handler);
>  	pci_epc_stop(epc);
> -	for (bar = BAR_0; bar <= BAR_5; bar++) {
> +	for (bar = 0; bar < PCI_STD_NUM_BARS; bar++) {
>  		epf_bar = &epf->bar[bar];
>  
>  		if (epf_test->reg[bar]) {
> @@ -400,7 +400,7 @@ static int pci_epf_test_set_bar(struct pci_epf *epf)
>  
>  	epc_features = epf_test->epc_features;
>  
> -	for (bar = BAR_0; bar <= BAR_5; bar += add) {
> +	for (bar = 0; bar < PCI_STD_NUM_BARS; bar += add) {

Is it possible to completely remove the BAR_x macros, or are there exsiting
users after this patchset?

As your patchset replaces BAR_0 with 0 and BAR_1 with 1, does this suggest
that other users of BAR_x should be removed and also replaced with a number?

Apologies if you this doesn't fall in the remit of this patchset.

Thanks,

Andrew Murray

>  		epf_bar = &epf->bar[bar];
>  		/*
>  		 * pci_epc_set_bar() sets PCI_BASE_ADDRESS_MEM_TYPE_64
> @@ -450,7 +450,7 @@ static int pci_epf_test_alloc_space(struct pci_epf *epf)
>  	}
>  	epf_test->reg[test_reg_bar] = base;
>  
> -	for (bar = BAR_0; bar <= BAR_5; bar += add) {
> +	for (bar = 0; bar < PCI_STD_NUM_BARS; bar += add) {
>  		epf_bar = &epf->bar[bar];
>  		add = (epf_bar->flags & PCI_BASE_ADDRESS_MEM_TYPE_64) ? 2 : 1;
>  
> @@ -478,7 +478,7 @@ static void pci_epf_configure_bar(struct pci_epf *epf,
>  	bool bar_fixed_64bit;
>  	int i;
>  
> -	for (i = BAR_0; i <= BAR_5; i++) {
> +	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
>  		epf_bar = &epf->bar[i];
>  		bar_fixed_64bit = !!(epc_features->bar_fixed_64bit & (1 << i));
>  		if (bar_fixed_64bit)
> diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h
> index f641badc2c61..56f1846b9d39 100644
> --- a/include/linux/pci-epc.h
> +++ b/include/linux/pci-epc.h
> @@ -117,7 +117,7 @@ struct pci_epc_features {
>  	unsigned int	msix_capable : 1;
>  	u8	reserved_bar;
>  	u8	bar_fixed_64bit;
> -	u64	bar_fixed_size[BAR_5 + 1];
> +	u64	bar_fixed_size[PCI_STD_NUM_BARS];
>  	size_t	align;
>  };
>  
> -- 
> 2.21.0
>
Denis Efremov (Oracle) Sept. 18, 2019, 2:20 p.m. UTC | #2
On 9/18/19 12:19 PM, Andrew Murray wrote:
> On Mon, Sep 16, 2019 at 11:41:36PM +0300, Denis Efremov wrote:
>> To iterate through all possible BARs, loop conditions refactored to the
>> *number* of BARs "i < PCI_STD_NUM_BARS", instead of the index of the last
>> valid BAR "i <= BAR_5". This is more idiomatic C style and allows to avoid
>> the fencepost error. Array definitions changed to PCI_STD_NUM_BARS where
>> appropriate.
>>
>> Cc: Kishon Vijay Abraham I <kishon@ti.com>
>> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
>> Signed-off-by: Denis Efremov <efremov@linux.com>
>> ---
>>  drivers/pci/endpoint/functions/pci-epf-test.c | 10 +++++-----
>>  include/linux/pci-epc.h                       |  2 +-
>>  2 files changed, 6 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c
>> index 1cfe3687a211..5d74f81ddfe4 100644
>> --- a/drivers/pci/endpoint/functions/pci-epf-test.c
>> +++ b/drivers/pci/endpoint/functions/pci-epf-test.c
>> @@ -44,7 +44,7 @@
>>  static struct workqueue_struct *kpcitest_workqueue;
>>  
>>  struct pci_epf_test {
>> -	void			*reg[6];
>> +	void			*reg[PCI_STD_NUM_BARS];
>>  	struct pci_epf		*epf;
>>  	enum pci_barno		test_reg_bar;
>>  	struct delayed_work	cmd_handler;
>> @@ -377,7 +377,7 @@ static void pci_epf_test_unbind(struct pci_epf *epf)
>>  
>>  	cancel_delayed_work(&epf_test->cmd_handler);
>>  	pci_epc_stop(epc);
>> -	for (bar = BAR_0; bar <= BAR_5; bar++) {
>> +	for (bar = 0; bar < PCI_STD_NUM_BARS; bar++) {
>>  		epf_bar = &epf->bar[bar];
>>  
>>  		if (epf_test->reg[bar]) {
>> @@ -400,7 +400,7 @@ static int pci_epf_test_set_bar(struct pci_epf *epf)
>>  
>>  	epc_features = epf_test->epc_features;
>>  
>> -	for (bar = BAR_0; bar <= BAR_5; bar += add) {
>> +	for (bar = 0; bar < PCI_STD_NUM_BARS; bar += add) {
> 
> Is it possible to completely remove the BAR_x macros, or are there exsiting
> users after this patchset?

They are still used in other parts of the code. So, I've decided to preserve
the defines in this case.

pci-epc-core.c
400:        (epf_bar->barno == BAR_5 &&
429:        (epf_bar->barno == BAR_5 &&
functions/pci-epf-test.c
497:    enum pci_barno test_reg_bar = BAR_0;

> 
> As your patchset replaces BAR_0 with 0 and BAR_1 with 1, does this suggest
> that other users of BAR_x should be removed and also replaced with a number?

I changed BAR_0 to 0 in order to not mix different notions, i.e. the number
of bars and the concrete bar.

> 
> Apologies if you this doesn't fall in the remit of this patchset.

I don't know what is better here. It's simple enough to remove these defines.
However, I would prefer to wait for the endpoint developers opinion.

Thanks for the review!
Denis

> 
> Thanks,
> 
> Andrew Murray
> 
>>  		epf_bar = &epf->bar[bar];
>>  		/*
>>  		 * pci_epc_set_bar() sets PCI_BASE_ADDRESS_MEM_TYPE_64
>> @@ -450,7 +450,7 @@ static int pci_epf_test_alloc_space(struct pci_epf *epf)
>>  	}
>>  	epf_test->reg[test_reg_bar] = base;
>>  
>> -	for (bar = BAR_0; bar <= BAR_5; bar += add) {
>> +	for (bar = 0; bar < PCI_STD_NUM_BARS; bar += add) {
>>  		epf_bar = &epf->bar[bar];
>>  		add = (epf_bar->flags & PCI_BASE_ADDRESS_MEM_TYPE_64) ? 2 : 1;
>>  
>> @@ -478,7 +478,7 @@ static void pci_epf_configure_bar(struct pci_epf *epf,
>>  	bool bar_fixed_64bit;
>>  	int i;
>>  
>> -	for (i = BAR_0; i <= BAR_5; i++) {
>> +	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
>>  		epf_bar = &epf->bar[i];
>>  		bar_fixed_64bit = !!(epc_features->bar_fixed_64bit & (1 << i));
>>  		if (bar_fixed_64bit)
>> diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h
>> index f641badc2c61..56f1846b9d39 100644
>> --- a/include/linux/pci-epc.h
>> +++ b/include/linux/pci-epc.h
>> @@ -117,7 +117,7 @@ struct pci_epc_features {
>>  	unsigned int	msix_capable : 1;
>>  	u8	reserved_bar;
>>  	u8	bar_fixed_64bit;
>> -	u64	bar_fixed_size[BAR_5 + 1];
>> +	u64	bar_fixed_size[PCI_STD_NUM_BARS];
>>  	size_t	align;
>>  };
>>  
>> -- 
>> 2.21.0
>>
diff mbox series

Patch

diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c
index 1cfe3687a211..5d74f81ddfe4 100644
--- a/drivers/pci/endpoint/functions/pci-epf-test.c
+++ b/drivers/pci/endpoint/functions/pci-epf-test.c
@@ -44,7 +44,7 @@ 
 static struct workqueue_struct *kpcitest_workqueue;
 
 struct pci_epf_test {
-	void			*reg[6];
+	void			*reg[PCI_STD_NUM_BARS];
 	struct pci_epf		*epf;
 	enum pci_barno		test_reg_bar;
 	struct delayed_work	cmd_handler;
@@ -377,7 +377,7 @@  static void pci_epf_test_unbind(struct pci_epf *epf)
 
 	cancel_delayed_work(&epf_test->cmd_handler);
 	pci_epc_stop(epc);
-	for (bar = BAR_0; bar <= BAR_5; bar++) {
+	for (bar = 0; bar < PCI_STD_NUM_BARS; bar++) {
 		epf_bar = &epf->bar[bar];
 
 		if (epf_test->reg[bar]) {
@@ -400,7 +400,7 @@  static int pci_epf_test_set_bar(struct pci_epf *epf)
 
 	epc_features = epf_test->epc_features;
 
-	for (bar = BAR_0; bar <= BAR_5; bar += add) {
+	for (bar = 0; bar < PCI_STD_NUM_BARS; bar += add) {
 		epf_bar = &epf->bar[bar];
 		/*
 		 * pci_epc_set_bar() sets PCI_BASE_ADDRESS_MEM_TYPE_64
@@ -450,7 +450,7 @@  static int pci_epf_test_alloc_space(struct pci_epf *epf)
 	}
 	epf_test->reg[test_reg_bar] = base;
 
-	for (bar = BAR_0; bar <= BAR_5; bar += add) {
+	for (bar = 0; bar < PCI_STD_NUM_BARS; bar += add) {
 		epf_bar = &epf->bar[bar];
 		add = (epf_bar->flags & PCI_BASE_ADDRESS_MEM_TYPE_64) ? 2 : 1;
 
@@ -478,7 +478,7 @@  static void pci_epf_configure_bar(struct pci_epf *epf,
 	bool bar_fixed_64bit;
 	int i;
 
-	for (i = BAR_0; i <= BAR_5; i++) {
+	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
 		epf_bar = &epf->bar[i];
 		bar_fixed_64bit = !!(epc_features->bar_fixed_64bit & (1 << i));
 		if (bar_fixed_64bit)
diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h
index f641badc2c61..56f1846b9d39 100644
--- a/include/linux/pci-epc.h
+++ b/include/linux/pci-epc.h
@@ -117,7 +117,7 @@  struct pci_epc_features {
 	unsigned int	msix_capable : 1;
 	u8	reserved_bar;
 	u8	bar_fixed_64bit;
-	u64	bar_fixed_size[BAR_5 + 1];
+	u64	bar_fixed_size[PCI_STD_NUM_BARS];
 	size_t	align;
 };