Re: [PATCH 11/12] cxgb4: Search VPD with pci_vpd_find_ro_info_keyword()

[Heiner Kallweit <hkallweit1@gmail.com>]

On 24.08.2021 19:11, Bjorn Helgaas wrote:
> On Sun, Aug 22, 2021 at 03:59:21PM +0200, Heiner Kallweit wrote:
>> Use pci_vpd_find_ro_info_keyword() to search for keywords in VPD to
>> simplify the code.
>>
>> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
>> ---
>>  drivers/net/ethernet/chelsio/cxgb4/t4_hw.c | 67 +++++++++-------------
>>  1 file changed, 27 insertions(+), 40 deletions(-)
>>
>> diff --git a/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c b/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c
>> index 2aeb2f80f..5e8ac42ac 100644
>> --- a/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c
>> +++ b/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c
>> @@ -2743,10 +2743,9 @@ int t4_seeprom_wp(struct adapter *adapter, bool enable)
>>   */
>>  int t4_get_raw_vpd_params(struct adapter *adapter, struct vpd_params *p)
>>  {
>> -	int i, ret = 0, addr;
>> -	int sn, pn, na;
>> +	unsigned int id_len, pn_len, sn_len, na_len;
>> +	int sn, pn, na, addr, ret = 0;
>>  	u8 *vpd, base_val = 0;
>> -	unsigned int vpdr_len, kw_offset, id_len;
>>  
>>  	vpd = vmalloc(VPD_LEN);
>>  	if (!vpd)
>> @@ -2772,60 +2771,48 @@ int t4_get_raw_vpd_params(struct adapter *adapter, struct vpd_params *p)
>>  	}
>>  
>>  	id_len = pci_vpd_lrdt_size(vpd);
>> -	if (id_len > ID_LEN)
>> -		id_len = ID_LEN;
>>  
>> -	i = pci_vpd_find_tag(vpd, VPD_LEN, PCI_VPD_LRDT_RO_DATA);
>> -	if (i < 0) {
>> -		dev_err(adapter->pdev_dev, "missing VPD-R section\n");
>> +	ret = pci_vpd_check_csum(vpd, VPD_LEN);
>> +	if (ret) {
>> +		dev_err(adapter->pdev_dev, "VPD checksum incorrect or missing\n");
>>  		ret = -EINVAL;
>>  		goto out;
>>  	}
>>  
>> -	vpdr_len = pci_vpd_lrdt_size(&vpd[i]);
>> -	kw_offset = i + PCI_VPD_LRDT_TAG_SIZE;
>> -	if (vpdr_len + kw_offset > VPD_LEN) {
>> -		dev_err(adapter->pdev_dev, "bad VPD-R length %u\n", vpdr_len);
>> -		ret = -EINVAL;
>> +	ret = pci_vpd_find_ro_info_keyword(vpd, VPD_LEN,
>> +					   PCI_VPD_RO_KEYWORD_SERIALNO, &sn_len);
>> +	if (ret < 0)
>>  		goto out;
>> -	}
>> +	sn = ret;
>>  
>> -#define FIND_VPD_KW(var, name) do { \
>> -	var = pci_vpd_find_info_keyword(vpd, kw_offset, vpdr_len, name); \
>> -	if (var < 0) { \
>> -		dev_err(adapter->pdev_dev, "missing VPD keyword " name "\n"); \
> 
> Just for the record, I guess this patch gives up these error messages
> that mention the specific keyword that's missing?  Not really an issue
> for *me*, since the people generating the VPD content should be able to
> easily validate this and figure out any errors.  Just pointing it out
> in case the cxgb4 folks are attached to the messages.
> 
Right. My thought was: With userspace tools like "lspci -vv" or
"od <path>/vpd" it's easy to check the actual content of VPD and find
out which keyword is missing. Therefore the missing keyword doesn't
necessarily has to be referenced in an error message.

>> -		ret = -EINVAL; \
>> -		goto out; \
>> -	} \
>> -	var += PCI_VPD_INFO_FLD_HDR_SIZE; \
>> -} while (0)
>> -
>> -	ret = pci_vpd_check_csum(vpd, VPD_LEN);
>> -	if (ret) {
>> -		dev_err(adapter->pdev_dev, "VPD checksum incorrect or missing\n");
>> -		ret = -EINVAL;
>> +	ret = pci_vpd_find_ro_info_keyword(vpd, VPD_LEN,
>> +					   PCI_VPD_RO_KEYWORD_PARTNO, &pn_len);
>> +	if (ret < 0)
>>  		goto out;
>> -	}
>> +	pn = ret;
>>  
>> -	FIND_VPD_KW(sn, "SN");
>> -	FIND_VPD_KW(pn, "PN");
>> -	FIND_VPD_KW(na, "NA");
>> -#undef FIND_VPD_KW
>> +	ret = pci_vpd_find_ro_info_keyword(vpd, VPD_LEN, "NA", &na_len);
>> +	if (ret < 0)
>> +		goto out;
>> +	na = ret;
>>  
>> -	memcpy(p->id, vpd + PCI_VPD_LRDT_TAG_SIZE, id_len);
>> +	memcpy(p->id, vpd + PCI_VPD_LRDT_TAG_SIZE, min_t(int, id_len, ID_LEN));
>>  	strim(p->id);
>> -	i = pci_vpd_info_field_size(vpd + sn - PCI_VPD_INFO_FLD_HDR_SIZE);
>> -	memcpy(p->sn, vpd + sn, min(i, SERNUM_LEN));
>> +	memcpy(p->sn, vpd + sn, min_t(int, sn_len, SERNUM_LEN));
>>  	strim(p->sn);
>> -	i = pci_vpd_info_field_size(vpd + pn - PCI_VPD_INFO_FLD_HDR_SIZE);
>> -	memcpy(p->pn, vpd + pn, min(i, PN_LEN));
>> +	memcpy(p->pn, vpd + pn, min_t(int, pn_len, PN_LEN));
>>  	strim(p->pn);
>> -	memcpy(p->na, vpd + na, min(i, MACADDR_LEN));
>> +	memcpy(p->na, vpd + na, min_t(int, na_len, MACADDR_LEN));
>>  	strim((char *)p->na);
>>  
>>  out:
>>  	vfree(vpd);
>> -	return ret < 0 ? ret : 0;
>> +	if (ret < 0) {
>> +		dev_err(adapter->pdev_dev, "error reading VPD\n");
>> +		return ret;
>> +	}
>> +
>> +	return 0;
>>  }
>>  
>>  /**
>> -- 
>> 2.33.0
>>
>>