>On Mon, Dec 28, 2015 at 9:29 PM, <Jordan_Hargrave@xxxxxxxx> wrote: >> 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 > >Can you please repost this as a patch instead of as a reply to our >thread about VPD size. The fact is the subject is misleading as your >patch isn't actually related to VPD sizing. > I had already posted this a few weeks back but never got any feedback. [PATCH] Create sysfs entries for VPD-R keys https://marc.info/?l=linux-pci&m=144959803316031&w=2 >> 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); >> +} >> + > >So I assume there is another patch that implements >pci_vpd_find_info_keyword so that it can go through the vpdr_data and >parse it? > That's already an existing function in drivers/pci/vpd.c >> +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; > >I'm not really sure this is the right place for this type of quirk. >If this is really an issue maybe we should just disable VPD for these >devices. Otherwise there isn't anything to stop someone from going in >and reading the VPD region via the existing VPD interfaces. > This could be moved elsewhere. There's a similar quirk for megaraid cards that was posted recently. [PATCH v4] pci: Limit VPD length for megaraid_sas adapter >> + 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; >> + > >Why not cache the ID string as well? Seems like it might be a field >people would want to read on a regular basis in order to find out what >is there. > I could add that. What should attribute be called, 'vpdinfo', 'vpdi', etc? >> + 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; >> +} >> + > >This bit here needs to reset vpdr_data back to NULL. Otherwise you >could cause memory corruption via a double free in your two clean-up >routines called out below. Ok will fix that. -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
