Re: [PATCH v2 7/9] PCI: endpoint: Add the function number as argument to EPC ops

From: Cyrille Pitchen
Date: Fri Dec 29 2017 - 15:30:09 EST


Hi Kishon,

Le 29/12/2017 à 10:23, Kishon Vijay Abraham I a écrit :
> Hi,
>
> On Monday 18 December 2017 11:46 PM, Cyrille Pitchen wrote:
>> This patch updates the prototype of most handlers from 'struct
>> pci_epc_ops' so the EPC library can now support multi-function devices.
>>
>> Signed-off-by: Cyrille Pitchen <cyrille.pitchen@xxxxxxxxxxxxxxxxxx>
>> ---
>> drivers/pci/dwc/pcie-designware-ep.c | 20 +++++----
>> drivers/pci/endpoint/functions/pci-epf-test.c | 41 ++++++++++--------
>> drivers/pci/endpoint/pci-epc-core.c | 62 ++++++++++++++++-----------
>> include/linux/pci-epc.h | 43 +++++++++++--------
>> 4 files changed, 96 insertions(+), 70 deletions(-)
>>
[...]
>> diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c
>> index cd7d4788b94d..77420364a728 100644
>> --- a/drivers/pci/endpoint/pci-epc-core.c
>> +++ b/drivers/pci/endpoint/pci-epc-core.c
>> @@ -141,25 +141,26 @@ EXPORT_SYMBOL_GPL(pci_epc_start);
>> /**
>> * pci_epc_raise_irq() - interrupt the host system
>> * @epc: the EPC device which has to interrupt the host
>> + * @func_no: the endpoint function number in the EPC device
>> * @type: specify the type of interrupt; legacy or MSI
>> * @interrupt_num: the MSI interrupt number
>> *
>> * Invoke to raise an MSI or legacy interrupt
>> */
>> -int pci_epc_raise_irq(struct pci_epc *epc, enum pci_epc_irq_type type,
>> - u8 interrupt_num)
>> +int pci_epc_raise_irq(struct pci_epc *epc, u8 func_no,
>> + enum pci_epc_irq_type type, u8 interrupt_num)
>> {
>> int ret;
>> unsigned long flags;
>>
>> - if (IS_ERR(epc))
>> + if (IS_ERR(epc) || func_no > BAR_5)
>
> why is function number compared with BAR? here and everywhere below..
>

Oops! sorry for that. Actually it's a silly mistake, thanks for
catching it!

I plan to fix it replacing with something like this:

s/func_no > BAR_5/func_no >= epc->max_functions/

Then I guess if we already test with IS_ERR(), I should now replace
IS_ERR() by IS_ERR_OR_NULL() before dereferencing epc when reading
max_functions.

Best regards,

Cyrille

> Thanks
> Kishon
>


--
Cyrille Pitchen, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com