Re: [libvirt PATCH v5 1/7] 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. A GTree is used as a data structure in order to maintain key ordering which will be important in XML to XML tests later. 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 | 15 + src/util/meson.build | 1 + src/util/virpcivpd.c | 755 ++++++++++++++++++++++++++++++++++++++ src/util/virpcivpd.h | 117 ++++++ src/util/virpcivpdpriv.h | 45 +++ tests/meson.build | 1 + tests/testutils.c | 40 ++ tests/testutils.h | 4 + tests/virpcivpdtest.c | 705 +++++++++++++++++++++++++++++++++++ 11 files changed, 1686 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 diff --git a/build-aux/syntax-check.mk b/build-aux/syntax-check.mk index cb54c8ba36..a428831380 100644 --- a/build-aux/syntax-check.mk +++ b/build-aux/syntax-check.mk @@ -775,9 +775,9 @@ sc_prohibit_windows_special_chars_in_filename: { echo '$(ME): Windows special chars in filename not allowed' 1>&2; echo exit 1; } || : sc_prohibit_mixed_case_abbreviations: - @prohibit='Pci|Usb|Scsi' \ + @prohibit='Pci|Usb|Scsi|Vpd' \ in_vc_files='\.[ch]$$' \ - halt='Use PCI, USB, SCSI, not Pci, Usb, Scsi' \ + halt='Use PCI, USB, SCSI, VPD, not Pci, Usb, Scsi, Vpd' \ $(_sc_search_regexp) # Require #include <locale.h> in all files that call setlocale() diff --git a/po/POTFILES.in b/po/POTFILES.in index c200d7452a..4be4139529 100644 --- a/po/POTFILES.in +++ b/po/POTFILES.in @@ -302,6 +302,7 @@ @SRCDIR(a)src/util/virnvme.c @SRCDIR(a)src/util/virobject.c @SRCDIR(a)src/util/virpci.c +@SRCDIR(a)src/util/virpcivpd.c @SRCDIR(a)src/util/virperf.c @SRCDIR(a)src/util/virpidfile.c @SRCDIR(a)src/util/virpolkit.c diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms index 6de9d9aef1..bb9b380599 100644 --- a/src/libvirt_private.syms +++ b/src/libvirt_private.syms @@ -3571,6 +3571,21 @@ virVHBAManageVport; virVHBAPathExists; +# util/virpcivpd.h + +virPCIVPDKeywordResourceForEach; +virPCIVPDKeywordResourceNew; +virPCIVPDParse; +virPCIVPDParseVPDLargeResourceFields; +virPCIVPDParseVPDLargeResourceString; +virPCIVPDReadVPDBytes; +virPCIVPDResourceGetFieldValueFormat; +virPCIVPDResourceGetResourceType; +virPCIVPDResourceIsExpectedKeyword; +virPCIVPDResourceIsValidTextValue; +virPCIVPDStringResourceGetValue; +virPCIVPDStringResourceNew; + # util/virvsock.h virVsockAcquireGuestCid; virVsockSetGuestCid; diff --git a/src/util/meson.build b/src/util/meson.build index 05934f6841..24350a3e67 100644 --- a/src/util/meson.build +++ b/src/util/meson.build @@ -105,6 +105,7 @@ util_sources = [ 'virutil.c', 'viruuid.c', 'virvhba.c', + 'virpcivpd.c', 'virvsock.c', 'virxml.c', ] diff --git a/src/util/virpcivpd.c b/src/util/virpcivpd.c new file mode 100644 index 0000000000..849ea0570c --- /dev/null +++ b/src/util/virpcivpd.c @@ -0,0 +1,755 @@ +/* + * virpcivpd.c: helper APIs for working with the PCI/PCIe VPD capability + * + * Copyright (C) 2021 Canonical Ltd. + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library. If not, see + * <http://www.gnu.org/licenses/>;. + */ + +#include <config.h> + +#ifdef __linux__ +# include <unistd.h> +#endif + +#define LIBVIRT_VIRPCIVPDPRIV_H_ALLOW + +#include "virpcivpdpriv.h" +#include "virlog.h" +#include "virerror.h" +#include "virfile.h" + +#define VIR_FROM_THIS VIR_FROM_NONE + +VIR_LOG_INIT("util.pcivpd"); + +GType +vir_pci_vpd_resource_type_get_type(void) +{ + static GType resourceType; + + static const GEnumValue resourceTypes[] = { + {VIR_PCI_VPD_RESOURCE_TYPE_STRING, "String resource", "string"}, + {VIR_PCI_VPD_RESOURCE_TYPE_VPD_R, "Read-only resource", "vpd-r"}, + {VIR_PCI_VPD_RESOURCE_TYPE_VPD_W, "Read-write resource", "vpd-w"}, + {VIR_PCI_VPD_RESOURCE_TYPE_LAST, "last", "last"}, + {0, NULL, NULL}, + }; + + if (!resourceType) { + resourceType = g_enum_register_static("virPCIVPDResourceType", resourceTypes); + } + return resourceType; +} + +static gboolean +virPCIVPDResourceIsVendorKeyword(const gchar *keyword) +{ + return g_str_has_prefix(keyword, "V"); +} + +static gboolean +virPCIVPDResourceIsSystemKeyword(const gchar *keyword) +{ + /* Special-case the system-specific keywords since they share the "Y" prefix with "YA". */ + return g_str_has_prefix(keyword, "Y") && STRNEQ(keyword, "YA"); +} + +static gchar * +virPCIVPDResourceGetKeywordPrefix(const gchar *keyword) +{ + g_autofree gchar *key = NULL; + + /* Keywords must have a length of 2 bytes. */ + if (strlen(keyword) != 2) { + virReportError(VIR_ERR_INTERNAL_ERROR, _("The keyword length is not 2 bytes: %s"), keyword); + return NULL; + } else if (!(g_ascii_isalnum(keyword[0]) && g_ascii_isalnum(keyword[1]))) { + virReportError(VIR_ERR_INTERNAL_ERROR, "%s", + _("The keyword contains non-alphanumeric ASCII characters")); + return NULL; + } + /* Special-case the system-specific keywords since they share the "Y" prefix with "YA". */ + if (virPCIVPDResourceIsSystemKeyword(keyword) || virPCIVPDResourceIsVendorKeyword(keyword)) { + key = g_strndup(keyword, 1); + } else { + key = g_strndup(keyword, 2); + } + return g_steal_pointer(&key); +} + +/** + * virPCIVPDResourceGetFieldValueFormat: + * @keyword: A keyword for which to get a value type + * + * Returns: a virPCIVPDResourceFieldValueFormat value which specifies the field value type for + * a provided keyword based on the static information from PCI(e) specs. + */ +virPCIVPDResourceFieldValueFormat +virPCIVPDResourceGetFieldValueFormat(const gchar *keyword) +{ + static GHashTable *fieldValueFormats; + g_autofree gchar *key = NULL; + gpointer keyVal = NULL; + virPCIVPDResourceFieldValueFormat format = VIR_PCI_VPD_RESOURCE_FIELD_VALUE_FORMAT_LAST; + + /* Keywords are expected to be 2 bytes in length which is defined in the specs. */ + if (strlen(keyword) != 2) { + return VIR_PCI_VPD_RESOURCE_FIELD_VALUE_FORMAT_LAST; + } + + if (!fieldValueFormats) {

+ /* Initialize a hash table once with static format metadata coming from the PCI(e) specs. + * The VPD format does not embed format metadata into the resource records so it is not + * possible to do format discovery without static information. Legacy PICMIG keywords + * are not included. */ + fieldValueFormats = g_hash_table_new(g_str_hash, g_str_equal); + /* Extended capability. Contains binary data per PCI(e) specs. */ + g_hash_table_insert(fieldValueFormats, g_strdup("CP"),

+ GINT_TO_POINTER(VIR_PCI_VPD_RESOURCE_FIELD_VALUE_FORMAT_BINARY)); + /* Engineering Change Level of an Add-in Card. */ + g_hash_table_insert(fieldValueFormats, g_strdup("EC"), + GINT_TO_POINTER(VIR_PCI_VPD_RESOURCE_FIELD_VALUE_FORMAT_TEXT)); + /* Manufacture ID */ + g_hash_table_insert(fieldValueFormats, g_strdup("MN"), + GINT_TO_POINTER(VIR_PCI_VPD_RESOURCE_FIELD_VALUE_FORMAT_TEXT)); + /* Add-in Card Part Number */ + g_hash_table_insert(fieldValueFormats, g_strdup("PN"), + GINT_TO_POINTER(VIR_PCI_VPD_RESOURCE_FIELD_VALUE_FORMAT_TEXT)); + /* Checksum and Reserved */ + g_hash_table_insert(fieldValueFormats, g_strdup("RV"), + GINT_TO_POINTER(VIR_PCI_VPD_RESOURCE_FIELD_VALUE_FORMAT_RESVD)); + /* Remaining Read/Write Area */ + g_hash_table_insert(fieldValueFormats, g_strdup("RW"), + GINT_TO_POINTER(VIR_PCI_VPD_RESOURCE_FIELD_VALUE_FORMAT_RDWR)); + /* Serial Number */ + g_hash_table_insert(fieldValueFormats, g_strdup("SN"), + GINT_TO_POINTER(VIR_PCI_VPD_RESOURCE_FIELD_VALUE_FORMAT_TEXT)); + /* Asset Tag Identifier */ + g_hash_table_insert(fieldValueFormats, g_strdup("YA"), + GINT_TO_POINTER(VIR_PCI_VPD_RESOURCE_FIELD_VALUE_FORMAT_TEXT)); + /* This is a vendor specific item and the characters are alphanumeric. The second + * character (x) of the keyword can be 0 through Z so only the first one is stored. */ + g_hash_table_insert(fieldValueFormats, g_strdup("V"), + GINT_TO_POINTER(VIR_PCI_VPD_RESOURCE_FIELD_VALUE_FORMAT_TEXT)); + /* This is a system specific item and the characters are alphanumeric. + * The second character (x) of the keyword can be 0 through 9 and B through Z. */ + g_hash_table_insert(fieldValueFormats, g_strdup("Y"), + GINT_TO_POINTER(VIR_PCI_VPD_RESOURCE_FIELD_VALUE_FORMAT_TEXT)); + } + + /* The system and vendor-specific keywords have a variable part - lookup + * the prefix significant for determining the value format. */ + key = virPCIVPDResourceGetKeywordPrefix(keyword); + if (key) { + keyVal = g_hash_table_lookup(fieldValueFormats, key); + if (keyVal) { + format = GPOINTER_TO_INT(keyVal); + } + } + return format; +}

+/** + * virPCIVPDResourceIsValidTextValue: + * @value: A NULL-terminated string to assess. + * + * Returns: a boolean indicating whether this value is a valid string resource + * value or text field value. The expectations are based on the keywords specified + * in relevant sections of PCI(e) specifications + * ("I.3. VPD Definitions" in PCI specs, "6.28.1 VPD Format" PCIe 4.0). + */ +gboolean +virPCIVPDResourceIsValidTextValue(const gchar *value) +{ + /* + * The PCI(e) specs mention alphanumeric characters when talking about text fields + * and the string resource but also include spaces and dashes in the provided example. + * Dots, commas, equal signs have also been observed in values used by major device vendors. + * The specs do not specify a full set of allowed code points and for Libvirt it is important + * to keep values in the ranges allowed within XML elements (mainly excluding less-than, + * greater-than and ampersand). + */ + if (!g_regex_match_simple("^[a-zA-Z0-9\\-_\\s,.:=]*$", value, 0, 0)) {

+/* + * PCI Local bus (2.2+, Appendix I) and PCIe 4.0+ (7.9.19 VPD Capability) define + * the VPD capability structure (8 bytes in total) and VPD registers that can be used to access + * VPD data including: + * bit 31 of the first 32-bit DWORD: data transfer completion flag (between the VPD data register + * and the VPD data storage hardware); + * bits 30:16 of the first 32-bit DWORD: VPD address of the first VPD data byte to be accessed; + * bits 31:0 of the second 32-bit DWORD: VPD data bytes with LSB being pointed to by the VPD address. + * + * Given that only 15 bits (30:16) are allocated for VPD address its mask is 0x7fff. +*/ +#define PCI_VPD_ADDR_MASK 0x7FFF + +/* + * VPD data consists of small and large resource data types. Information within a resource type + * consists of a 2-byte keyword, 1-byte length and data bytes (up to 255). +*/ +#define PCI_VPD_MAX_FIELD_SIZE 255 +#define PCI_VPD_LARGE_RESOURCE_FLAG 0x80 +#define PCI_VPD_STRING_RESOURCE_FLAG 0x02 +#define PCI_VPD_READ_ONLY_LARGE_RESOURCE_FLAG 0x10 +#define PCI_VPD_READ_WRITE_LARGE_RESOURCE_FLAG 0x11 +#define PCI_VPD_RESOURCE_END_TAG 0x0F +#define PCI_VPD_RESOURCE_END_VAL PCI_VPD_RESOURCE_END_TAG << 3 +#define VIR_TYPE_PCI_VPD_RESOURCE_TYPE vir_pci_vpd_resource_type_get_type() + +G_BEGIN_DECLS;

+#ifdef __linux__ +/** + * virCreateAnonymousFile: + * @data: a pointer to data to be written into a new file. + * @len: the length of data to be written (in bytes). + * + * Create a fake fd, write initial data to it. + * + */ +int +virCreateAnonymousFile(const uint8_t *data, size_t len) +{ + int fd = -1; + char path[] = abs_builddir "testutils-memfd-XXXXXX"; + /* A temp file is used since not all supported distributions support memfd. */ + if ((fd = g_mkstemp_full(path, O_RDWR | O_CLOEXEC, S_IRUSR | S_IWUSR)) < 0) { + return fd; + } + g_unlink(path); + + if (ftruncate(fd, len) != 0) { + VIR_TEST_DEBUG("%s: %s", "failed to ftruncate an anonymous file", + g_strerror(errno)); + goto cleanup; + }

+ if (safewrite(fd, data, len) != len) { + VIR_TEST_DEBUG("%s: %s", "failed to write to an anonymous file", + g_strerror(errno)); + goto cleanup; + } + return fd; + cleanup: + if (VIR_CLOSE(fd) < 0) { + VIR_TEST_DEBUG("%s: %s", "failed to close an anonymous file", + g_strerror(errno)); + } + return -1; +} +#endif