Re: [libvirt PATCH v7 1/5] Add a PCI/PCIe device VPD Parser

Add support for deserializing the binary PCI/PCIe VPD format and storing results in memory. The VPD format is specified in "I.3. VPD Definitions" in PCI specs (2.2+) and "6.28.1 VPD Format" PCIe 4.0. As section 6.28 in PCIe 4.0 notes, the PCI Local Bus and PCIe VPD formats are binary compatible and PCIe 4.0 merely started incorporating what was already present in PCI specs. Linux kernel exposes a binary blob in the VPD format via sysfs since v2.6.26 (commit 94e6108803469a37ee1e3c92dafdd1d59298602f) which requires a parser to interpret. Signed-off-by: Dmitrii Shcherbakov <dmitrii.shcherbakov(a)canonical.com&gt; --- build-aux/syntax-check.mk | 4 +- po/POTFILES.in | 1 + src/libvirt_private.syms | 18 + src/util/meson.build | 1 + src/util/virpcivpd.c | 754 +++++++++++++++++++++++++++++++++++ src/util/virpcivpd.h | 76 ++++ src/util/virpcivpdpriv.h | 83 ++++ tests/meson.build | 1 + tests/testutils.c | 35 ++ tests/testutils.h | 4 + tests/virpcivpdtest.c | 809 ++++++++++++++++++++++++++++++++++++++ 11 files changed, 1784 insertions(+), 2 deletions(-) create mode 100644 src/util/virpcivpd.c create mode 100644 src/util/virpcivpd.h create mode 100644 src/util/virpcivpdpriv.h create mode 100644 tests/virpcivpdtest.c

+size_t +virPCIVPDReadVPDBytes(int vpdFileFd, uint8_t *buf, size_t count, off_t offset, uint8_t *csum) +{ + ssize_t numRead = pread(vpdFileFd, buf, count, offset); + + if (numRead == -1) { + VIR_DEBUG("Unable to read %zu bytes at offset %ld from fd: %d", count, offset, vpdFileFd);

+ } else if (numRead) { + /* + * Update the checksum for every byte read. Per the PCI(e) specs + * the checksum is correct if the sum of all bytes in VPD from + * VPD address 0 up to and including the VPD-R RV field's first + * data byte is zero. + */ + while (count--) { + *csum += *buf; + buf++; + } + } + return numRead; +}