>On 12/18/2015 03:02 PM, Alexander Duyck wrote:
>> On Fri, Dec 18, 2015 at 5:57 AM, Hannes Reinecke <hare@xxxxxxx> wrote:
>>> On 12/18/2015 02:49 PM, Alexander Duyck wrote:
>>>>
>>>> On Fri, Dec 18, 2015 at 12:35 AM, Hannes Reinecke <hare@xxxxxxx> wrote:
>>>>>
>>>>> PCI-2.2 VPD entries have a maximum size of 32k, but might actually
>>>>> be smaller than that. To figure out the actual size one has to read
>>>>> the VPD area until the 'end marker' is reached.
>>>>> Trying to read VPD data beyond that marker results in 'interesting'
>>>>> effects, from simple read errors to crashing the card. And to make
>>>>> matters worse not every PCI card implements this properly, leaving
>>>>> us with no 'end' marker or even completely invalid data.
>>>>> This path modifies the size of the VPD attribute to the available
>>>>> size, or set it to '0' if no valid data could be read.
>>>>
>>>>
>>>> This isn't what I had in mind. There is no need to add an f0 version
>>>> of the size function. The size for all functions other than function
>>>> 0 when the F0 flag is set is 0. We aren't going to be reading their
>>>> VPD, we only read the VPD region of function 0.
>>>>
>>> Ah. (I'm a bit confused about the proposed action for VPD other than
>>> function 0).
>>> So the idea here is to _disallow_ access to VPDs from functions other than
>>> '0' unless these functions have different PCI IDs?
>>
>> If you take a look at the F0 functions what they do is bypass the VPD
>> of the functions other than function 0. As such setting the size to 0
>> should really have no effect since the VPD of the function isn't
>> actually read if the F0 flag is set.
>>
>Setting the size to '0' effectively inhibits you to read the VPD
>data. So if we were to return '0' for PCI devices with the F0 bit
>set we will never ever to be able to read (or write) _any_ VPD data
>for that PCI device/function.
>Which would be rendering all these F0 accessors pointless, and we
>might as well remove them.
>
I had posted a patch recently to enable exposing the VPD-R valyes to sysfs. I need access
to these to parse into systemd for network naming (biosdevname style names).
The VPD-R is a readonly area contained within the PCI Vital Product
data. There are some standard and vendor-specific keys stored in
this region.
PN = Part Number
SN = Serial Number
MN = Manufacturer ID
Vx = Vendor-specific (x=0..9 A..Z)
Biosdevname/Systemd will use these VPD keys for determining Network
partitioning and port numbers for NIC cards
Signed-off-by: Jordan Hargrave <Jordan_Hargrave@xxxxxxxx>
---
drivers/pci/pci-sysfs.c | 216 +++++++++++++++++++++++++++++++++++++++++++++++
include/linux/pci.h | 2 +
2 files changed, 218 insertions(+), 0 deletions(-)
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index eead54c..4966ece 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -1295,6 +1295,210 @@ static struct bin_attribute pcie_config_attr = {
.write = pci_write_config,
};
+static umode_t vpd_attr_exist(struct kobject *kobj,
+ struct attribute *attr, int n)
+{
+ struct device *dev;
+ struct pci_dev *pdev;
+ const char *name;
+ int i;
+
+ dev = container_of(kobj, struct device, kobj);
+ pdev = to_pci_dev(dev);
+
+ name = attr->name;
+ if (pdev->vpdr_data == NULL)
+ return 0;
+ i = pci_vpd_find_info_keyword(pdev->vpdr_data, 0,
+ pdev->vpdr_len, name);
+ return (i >= 0 ? S_IRUGO : 0);
+}
+
+static ssize_t vpd_attr_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct pci_dev *pdev;
+ const char *name;
+ char kv_data[257] = { 0 };
+ int i, len;
+
+ pdev = to_pci_dev(dev);
+ name = attr->attr.name;
+ if (pdev->vpdr_data == NULL)
+ return 0;
+ i = pci_vpd_find_info_keyword(pdev->vpdr_data, 0,
+ pdev->vpdr_len, name);
+ if (i >= 0) {
+ len = pci_vpd_info_field_size(&pdev->vpdr_data[i]);
+ memcpy(kv_data, pdev->vpdr_data + i +
+ PCI_VPD_INFO_FLD_HDR_SIZE, len);
+ return scnprintf(buf, PAGE_SIZE, "%s\n", kv_data);
+ }
+ return 0;
+}
+
+#define VPD_ATTR_RO(x) \
+struct device_attribute vpd ## x = { \
+ .attr = { .name = #x, .mode = S_IRUGO | S_IWUSR }, \
+ .show = vpd_attr_show \
+}
+
+VPD_ATTR_RO(PN);
+VPD_ATTR_RO(EC);
+VPD_ATTR_RO(MN);
+VPD_ATTR_RO(SN);
+VPD_ATTR_RO(V0);
+VPD_ATTR_RO(V1);
+VPD_ATTR_RO(V2);
+VPD_ATTR_RO(V3);
+VPD_ATTR_RO(V4);
+VPD_ATTR_RO(V5);
+VPD_ATTR_RO(V6);
+VPD_ATTR_RO(V7);
+VPD_ATTR_RO(V8);
+VPD_ATTR_RO(V9);
+VPD_ATTR_RO(VA);
+VPD_ATTR_RO(VB);
+VPD_ATTR_RO(VC);
+VPD_ATTR_RO(VD);
+VPD_ATTR_RO(VE);
+VPD_ATTR_RO(VF);
+VPD_ATTR_RO(VG);
+VPD_ATTR_RO(VH);
+VPD_ATTR_RO(VI);
+VPD_ATTR_RO(VJ);
+VPD_ATTR_RO(VK);
+VPD_ATTR_RO(VL);
+VPD_ATTR_RO(VM);
+VPD_ATTR_RO(VN);
+VPD_ATTR_RO(VO);
+VPD_ATTR_RO(VP);
+VPD_ATTR_RO(VQ);
+VPD_ATTR_RO(VR);
+VPD_ATTR_RO(VS);
+VPD_ATTR_RO(VT);
+VPD_ATTR_RO(VU);
+VPD_ATTR_RO(VV);
+VPD_ATTR_RO(VW);
+VPD_ATTR_RO(VX);
+VPD_ATTR_RO(VY);
+VPD_ATTR_RO(VZ);
+
+static struct attribute *vpd_attributes[] = {
+ &vpdPN.attr,
+ &vpdEC.attr,
+ &vpdMN.attr,
+ &vpdSN.attr,
+ &vpdV0.attr,
+ &vpdV1.attr,
+ &vpdV2.attr,
+ &vpdV3.attr,
+ &vpdV4.attr,
+ &vpdV5.attr,
+ &vpdV6.attr,
+ &vpdV7.attr,
+ &vpdV8.attr,
+ &vpdV9.attr,
+ &vpdVA.attr,
+ &vpdVB.attr,
+ &vpdVC.attr,
+ &vpdVD.attr,
+ &vpdVE.attr,
+ &vpdVF.attr,
+ &vpdVG.attr,
+ &vpdVH.attr,
+ &vpdVI.attr,
+ &vpdVJ.attr,
+ &vpdVK.attr,
+ &vpdVL.attr,
+ &vpdVM.attr,
+ &vpdVN.attr,
+ &vpdVO.attr,
+ &vpdVP.attr,
+ &vpdVQ.attr,
+ &vpdVR.attr,
+ &vpdVS.attr,
+ &vpdVT.attr,
+ &vpdVU.attr,
+ &vpdVV.attr,
+ &vpdVW.attr,
+ &vpdVX.attr,
+ &vpdVY.attr,
+ &vpdVZ.attr,
+ NULL,
+};
+
+static struct attribute_group vpd_attr_group = {
+ .name = "vpdr",
+ .attrs = vpd_attributes,
+ .is_visible = vpd_attr_exist,
+};
+
+
+static int pci_get_vpd_tag(struct pci_dev *dev, int off, int *len)
+{
+ u8 tag[3];
+ int rc, tlen;
+
+ *len = 0;
+ /* Quirk Atheros cards, reading VPD hangs system for 20s */
+ if (dev->vendor == PCI_VENDOR_ID_ATHEROS ||
+ dev->vendor == PCI_VENDOR_ID_ATTANSIC)
+ return -ENOENT;
+ rc = pci_read_vpd(dev, off, 1, tag);
+ if (rc != 1)
+ return -ENOENT;
+ if (tag[0] == 0x00 || tag[0] == 0xFF || tag[0] == 0x7F)
+ return -ENOENT;
+ if (tag[0] & PCI_VPD_LRDT) {
+ rc = pci_read_vpd(dev, off+1, 2, tag+1);
+ if (rc != 2)
+ return -ENOENT;
+ tlen = pci_vpd_lrdt_size(tag) +
+ PCI_VPD_LRDT_TAG_SIZE;
+ } else {
+ tlen = pci_vpd_srdt_size(tag) +
+ PCI_VPD_SRDT_TAG_SIZE;
+ tag[0] &= ~PCI_VPD_SRDT_LEN_MASK;
+ }
+ /* Verify VPD tag fits in area */
+ if (tlen + off > dev->vpd->len)
+ return -ENOENT;
+ *len = tlen;
+ return tag[0];
+}
+
+static int pci_load_vpdr(struct pci_dev *dev)
+{
+ int rlen, ilen, tag, rc;
+
+ /* Check for VPD-I and VPD-R tag */
+ tag = pci_get_vpd_tag(dev, 0, &ilen);
+ if (tag != PCI_VPD_LRDT_ID_STRING)
+ return -ENOENT;
+ tag = pci_get_vpd_tag(dev, ilen, &rlen);
+ if (tag != PCI_VPD_LRDT_RO_DATA)
+ return -ENOENT;
+
+ rlen -= PCI_VPD_LRDT_TAG_SIZE;
+ dev->vpdr_len = rlen;
+ dev->vpdr_data = kzalloc(rlen, GFP_ATOMIC);
+ if (dev->vpdr_data == NULL)
+ return -ENOMEM;
+
+ rc = pci_read_vpd(dev, ilen + PCI_VPD_LRDT_TAG_SIZE,
+ rlen, dev->vpdr_data);
+ if (rc != rlen)
+ goto error;
+ if (sysfs_create_group(&dev->dev.kobj, &vpd_attr_group))
+ goto error;
+ return 0;
+ error:
+ kfree(dev->vpdr_data);
+ dev->vpdr_len = 0;
+ return -ENOENT;
+}
+
static ssize_t reset_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
@@ -1340,6 +1544,8 @@ static int pci_create_capabilities_sysfs(struct pci_dev *dev)
return retval;
}
dev->vpd->attr = attr;
+
+ pci_load_vpdr(dev);
}
/* Active State Power Management */
@@ -1356,6 +1562,11 @@ static int pci_create_capabilities_sysfs(struct pci_dev *dev)
error:
pcie_aspm_remove_sysfs_dev_files(dev);
if (dev->vpd && dev->vpd->attr) {
+ if (dev->vpdr_data) {
+ sysfs_remove_group(&dev->dev.kobj, &vpd_attr_group);
+ kfree(dev->vpdr_data);
+ dev->vpdr_data = NULL;
+ }
sysfs_remove_bin_file(&dev->dev.kobj, dev->vpd->attr);
kfree(dev->vpd->attr);
}
@@ -1438,6 +1649,11 @@ err:
static void pci_remove_capabilities_sysfs(struct pci_dev *dev)
{
if (dev->vpd && dev->vpd->attr) {
+ if (dev->vpdr_data) {
+ sysfs_remove_group(&dev->dev.kobj, &vpd_attr_group);
+ kfree(dev->vpdr_data);
+ dev->vpdr_data = NULL;
+ }
sysfs_remove_bin_file(&dev->dev.kobj, dev->vpd->attr);
kfree(dev->vpd->attr);
}
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 6ae25aa..699cf11 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -372,6 +372,8 @@ struct pci_dev {
const struct attribute_group **msi_irq_groups;
#endif
struct pci_vpd *vpd;
+ int vpdr_len;
+ u8 *vpdr_data;
#ifdef CONFIG_PCI_ATS
union {
struct pci_sriov *sriov; /* SR-IOV capability related */
--
1.7.1
>Hence my confusion.
>
>Cheers,
>
>Hannes
>--
>Dr. Hannes Reinecke zSeries & Storage
>hare@xxxxxxx +49 911 74053 688
>SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg
>GF: F. Imendörffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton
>HRB 21284 (AG Nürnberg)
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