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libvirt/src/util/virpci.c
Chunyan Liu 66b4693269 pass stub driver name instead of pciFindStubDriver 
Pass stub driver name directly to pciDettachDevice and pciReAttachDevice to fit
for different libvirt drivers. For example, qemu driver prefers pci-stub, but
Xen prefers pciback.

Signed-off-by: Chunyan Liu <cyliu@suse.com>
2013-01-10 11:30:09 -05:00

2266 lines
60 KiB
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/*
* virpci.c: helper APIs for managing host PCI devices
*
* Copyright (C) 2009-2012 Red Hat, Inc.
*
* 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/>.
*
* Authors:
* Mark McLoughlin <markmc@redhat.com>
*/
#include <config.h>
#include "virpci.h"
#include <dirent.h>
#include <fcntl.h>
#include <inttypes.h>
#include <limits.h>
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <stdlib.h>
#include "virlog.h"
#include "viralloc.h"
#include "vircommand.h"
#include "virerror.h"
#include "virfile.h"
#define PCI_SYSFS "/sys/bus/pci/"
#define PCI_ID_LEN 10 /* "XXXX XXXX" */
#define PCI_ADDR_LEN 13 /* "XXXX:XX:XX.X" */
#define SRIOV_FOUND 0
#define SRIOV_NOT_FOUND 1
#define SRIOV_ERROR -1
struct _pciDevice {
unsigned domain;
unsigned bus;
unsigned slot;
unsigned function;
char name[PCI_ADDR_LEN]; /* domain:bus:slot.function */
char id[PCI_ID_LEN]; /* product vendor */
char *path;
const char *used_by; /* The domain which uses the device */
unsigned pcie_cap_pos;
unsigned pci_pm_cap_pos;
unsigned has_flr : 1;
unsigned has_pm_reset : 1;
unsigned managed : 1;
/* used by reattach function */
unsigned unbind_from_stub : 1;
unsigned remove_slot : 1;
unsigned reprobe : 1;
};
struct _pciDeviceList {
unsigned count;
pciDevice **devs;
};
/* For virReportOOMError() and virReportSystemError() */
#define VIR_FROM_THIS VIR_FROM_NONE
/* Specifications referenced in comments:
* PCI30 - PCI Local Bus Specification 3.0
* PCIe20 - PCI Express Base Specification 2.0
* BR12 - PCI-to-PCI Bridge Architecture Specification 1.2
* PM12 - PCI Bus Power Management Interface Specification 1.2
* ECN_AF - Advanced Capabilities for Conventional PCI ECN
*/
/* Type 0 config space header length; PCI30 Section 6.1 Configuration Space Organization */
#define PCI_CONF_LEN 0x100
#define PCI_CONF_HEADER_LEN 0x40
/* PCI30 6.2.1 */
#define PCI_HEADER_TYPE 0x0e /* Header type */
#define PCI_HEADER_TYPE_BRIDGE 0x1
#define PCI_HEADER_TYPE_MASK 0x7f
#define PCI_HEADER_TYPE_MULTI 0x80
/* PCI30 6.2.1 Device Identification */
#define PCI_CLASS_DEVICE 0x0a /* Device class */
/* Class Code for bridge; PCI30 D.7 Base Class 06h */
#define PCI_CLASS_BRIDGE_PCI 0x0604
/* PCI30 6.2.3 Device Status */
#define PCI_STATUS 0x06 /* 16 bits */
#define PCI_STATUS_CAP_LIST 0x10 /* Support Capability List */
/* PCI30 6.7 Capabilities List */
#define PCI_CAPABILITY_LIST 0x34 /* Offset of first capability list entry */
/* PM12 3.2.1 Capability Identifier */
#define PCI_CAP_ID_PM 0x01 /* Power Management */
/* PCI30 H Capability IDs */
#define PCI_CAP_ID_EXP 0x10 /* PCI Express */
/* ECN_AF 6.x.1.1 Capability ID for AF */
#define PCI_CAP_ID_AF 0x13 /* Advanced Features */
/* PCIe20 7.8.3 Device Capabilities Register (Offset 04h) */
#define PCI_EXP_DEVCAP 0x4 /* Device capabilities */
#define PCI_EXP_DEVCAP_FLR (1<<28) /* Function Level Reset */
/* Header type 1 BR12 3.2 PCI-to-PCI Bridge Configuration Space Header Format */
#define PCI_PRIMARY_BUS 0x18 /* BR12 3.2.5.2 Primary bus number */
#define PCI_SECONDARY_BUS 0x19 /* BR12 3.2.5.3 Secondary bus number */
#define PCI_SUBORDINATE_BUS 0x1a /* BR12 3.2.5.4 Highest bus number behind the bridge */
#define PCI_BRIDGE_CONTROL 0x3e
/* BR12 3.2.5.18 Bridge Control Register */
#define PCI_BRIDGE_CTL_RESET 0x40 /* Secondary bus reset */
/* PM12 3.2.4 Power Management Control/Status (Offset = 4) */
#define PCI_PM_CTRL 4 /* PM control and status register */
#define PCI_PM_CTRL_STATE_MASK 0x3 /* Current power state (D0 to D3) */
#define PCI_PM_CTRL_STATE_D0 0x0 /* D0 state */
#define PCI_PM_CTRL_STATE_D3hot 0x3 /* D3 state */
#define PCI_PM_CTRL_NO_SOFT_RESET 0x8 /* No reset for D3hot->D0 */
/* ECN_AF 6.x.1 Advanced Features Capability Structure */
#define PCI_AF_CAP 0x3 /* Advanced features capabilities */
#define PCI_AF_CAP_FLR 0x2 /* Function Level Reset */
#define PCI_EXP_FLAGS 0x2
#define PCI_EXP_FLAGS_TYPE 0x00f0
#define PCI_EXP_TYPE_DOWNSTREAM 0x6
#define PCI_EXT_CAP_BASE 0x100
#define PCI_EXT_CAP_LIMIT 0x1000
#define PCI_EXT_CAP_ID_MASK 0x0000ffff
#define PCI_EXT_CAP_OFFSET_SHIFT 20
#define PCI_EXT_CAP_OFFSET_MASK 0x00000ffc
#define PCI_EXT_CAP_ID_ACS 0x000d
#define PCI_EXT_ACS_CTRL 0x06
#define PCI_EXT_CAP_ACS_SV 0x01
#define PCI_EXT_CAP_ACS_RR 0x04
#define PCI_EXT_CAP_ACS_CR 0x08
#define PCI_EXT_CAP_ACS_UF 0x10
#define PCI_EXT_CAP_ACS_ENABLED (PCI_EXT_CAP_ACS_SV | \
PCI_EXT_CAP_ACS_RR | \
PCI_EXT_CAP_ACS_CR | \
PCI_EXT_CAP_ACS_UF)
static int
pciConfigOpen(pciDevice *dev, bool fatal)
{
int fd;
fd = open(dev->path, O_RDWR);
if (fd < 0) {
if (fatal) {
virReportSystemError(errno,
_("Failed to open config space file '%s'"),
dev->path);
} else {
char ebuf[1024];
VIR_WARN("Failed to open config space file '%s': %s",
dev->path, virStrerror(errno, ebuf, sizeof(ebuf)));
}
return -1;
}
VIR_DEBUG("%s %s: opened %s", dev->id, dev->name, dev->path);
return fd;
}
static void
pciConfigClose(pciDevice *dev, int cfgfd)
{
if (VIR_CLOSE(cfgfd) < 0) {
char ebuf[1024];
VIR_WARN("Failed to close config space file '%s': %s",
dev->path, virStrerror(errno, ebuf, sizeof(ebuf)));
}
}
static int
pciRead(pciDevice *dev,
int cfgfd,
unsigned pos,
uint8_t *buf,
unsigned buflen)
{
memset(buf, 0, buflen);
if (lseek(cfgfd, pos, SEEK_SET) != pos ||
saferead(cfgfd, buf, buflen) != buflen) {
char ebuf[1024];
VIR_WARN("Failed to read from '%s' : %s", dev->path,
virStrerror(errno, ebuf, sizeof(ebuf)));
return -1;
}
return 0;
}
static uint8_t
pciRead8(pciDevice *dev, int cfgfd, unsigned pos)
{
uint8_t buf;
pciRead(dev, cfgfd, pos, &buf, sizeof(buf));
return buf;
}
static uint16_t
pciRead16(pciDevice *dev, int cfgfd, unsigned pos)
{
uint8_t buf[2];
pciRead(dev, cfgfd, pos, &buf[0], sizeof(buf));
return (buf[0] << 0) | (buf[1] << 8);
}
static uint32_t
pciRead32(pciDevice *dev, int cfgfd, unsigned pos)
{
uint8_t buf[4];
pciRead(dev, cfgfd, pos, &buf[0], sizeof(buf));
return (buf[0] << 0) | (buf[1] << 8) | (buf[2] << 16) | (buf[3] << 24);
}
static int
pciWrite(pciDevice *dev,
int cfgfd,
unsigned pos,
uint8_t *buf,
unsigned buflen)
{
if (lseek(cfgfd, pos, SEEK_SET) != pos ||
safewrite(cfgfd, buf, buflen) != buflen) {
char ebuf[1024];
VIR_WARN("Failed to write to '%s' : %s", dev->path,
virStrerror(errno, ebuf, sizeof(ebuf)));
return -1;
}
return 0;
}
static void
pciWrite16(pciDevice *dev, int cfgfd, unsigned pos, uint16_t val)
{
uint8_t buf[2] = { (val >> 0), (val >> 8) };
pciWrite(dev, cfgfd, pos, &buf[0], sizeof(buf));
}
static void
pciWrite32(pciDevice *dev, int cfgfd, unsigned pos, uint32_t val)
{
uint8_t buf[4] = { (val >> 0), (val >> 8), (val >> 16), (val >> 24) };
pciWrite(dev, cfgfd, pos, &buf[0], sizeof(buf));
}
typedef int (*pciIterPredicate)(pciDevice *, pciDevice *, void *);
/* Iterate over available PCI devices calling @predicate
* to compare each one to @dev.
* Return -1 on error since we don't want to assume it is
* safe to reset if there is an error.
*/
static int
pciIterDevices(pciIterPredicate predicate,
pciDevice *dev,
pciDevice **matched,
void *data)
{
DIR *dir;
struct dirent *entry;
int ret = 0;
int rc;
*matched = NULL;
VIR_DEBUG("%s %s: iterating over " PCI_SYSFS "devices", dev->id, dev->name);
dir = opendir(PCI_SYSFS "devices");
if (!dir) {
VIR_WARN("Failed to open " PCI_SYSFS "devices");
return -1;
}
while ((entry = readdir(dir))) {
unsigned int domain, bus, slot, function;
pciDevice *check;
char *tmp;
/* Ignore '.' and '..' */
if (entry->d_name[0] == '.')
continue;
/* expected format: <domain>:<bus>:<slot>.<function> */
if (/* domain */
virStrToLong_ui(entry->d_name, &tmp, 16, &domain) < 0 || *tmp != ':' ||
/* bus */
virStrToLong_ui(tmp + 1, &tmp, 16, &bus) < 0 || *tmp != ':' ||
/* slot */
virStrToLong_ui(tmp + 1, &tmp, 16, &slot) < 0 || *tmp != '.' ||
/* function */
virStrToLong_ui(tmp + 1, NULL, 16, &function) < 0) {
VIR_WARN("Unusual entry in " PCI_SYSFS "devices: %s", entry->d_name);
continue;
}
check = pciGetDevice(domain, bus, slot, function);
if (!check) {
ret = -1;
break;
}
rc = predicate(dev, check, data);
if (rc < 0) {
/* the predicate returned an error, bail */
pciFreeDevice(check);
ret = -1;
break;
}
else if (rc == 1) {
VIR_DEBUG("%s %s: iter matched on %s", dev->id, dev->name, check->name);
*matched = check;
ret = 1;
break;
}
pciFreeDevice(check);
}
closedir(dir);
return ret;
}
static uint8_t
pciFindCapabilityOffset(pciDevice *dev, int cfgfd, unsigned capability)
{
uint16_t status;
uint8_t pos;
status = pciRead16(dev, cfgfd, PCI_STATUS);
if (!(status & PCI_STATUS_CAP_LIST))
return 0;
pos = pciRead8(dev, cfgfd, PCI_CAPABILITY_LIST);
/* Zero indicates last capability, capabilities can't
* be in the config space header and 0xff is returned
* by the kernel if we don't have access to this region
*
* Note: we're not handling loops or extended
* capabilities here.
*/
while (pos >= PCI_CONF_HEADER_LEN && pos != 0xff) {
uint8_t capid = pciRead8(dev, cfgfd, pos);
if (capid == capability) {
VIR_DEBUG("%s %s: found cap 0x%.2x at 0x%.2x",
dev->id, dev->name, capability, pos);
return pos;
}
pos = pciRead8(dev, cfgfd, pos + 1);
}
VIR_DEBUG("%s %s: failed to find cap 0x%.2x", dev->id, dev->name, capability);
return 0;
}
static unsigned int
pciFindExtendedCapabilityOffset(pciDevice *dev,
int cfgfd,
unsigned capability)
{
int ttl;
unsigned int pos;
uint32_t header;
/* minimum 8 bytes per capability */
ttl = (PCI_EXT_CAP_LIMIT - PCI_EXT_CAP_BASE) / 8;
pos = PCI_EXT_CAP_BASE;
while (ttl > 0 && pos >= PCI_EXT_CAP_BASE) {
header = pciRead32(dev, cfgfd, pos);
if ((header & PCI_EXT_CAP_ID_MASK) == capability)
return pos;
pos = (header >> PCI_EXT_CAP_OFFSET_SHIFT) & PCI_EXT_CAP_OFFSET_MASK;
ttl--;
}
return 0;
}
/* detects whether this device has FLR. Returns 0 if the device does
* not have FLR, 1 if it does, and -1 on error
*/
static int
pciDetectFunctionLevelReset(pciDevice *dev, int cfgfd)
{
uint32_t caps;
uint8_t pos;
char *path;
int found;
/* The PCIe Function Level Reset capability allows
* individual device functions to be reset without
* affecting any other functions on the device or
* any other devices on the bus. This is only common
* on SR-IOV NICs at the moment.
*/
if (dev->pcie_cap_pos) {
caps = pciRead32(dev, cfgfd, dev->pcie_cap_pos + PCI_EXP_DEVCAP);
if (caps & PCI_EXP_DEVCAP_FLR) {
VIR_DEBUG("%s %s: detected PCIe FLR capability", dev->id, dev->name);
return 1;
}
}
/* The PCI AF Function Level Reset capability is
* the same thing, except for conventional PCI
* devices. This is not common yet.
*/
pos = pciFindCapabilityOffset(dev, cfgfd, PCI_CAP_ID_AF);
if (pos) {
caps = pciRead16(dev, cfgfd, pos + PCI_AF_CAP);
if (caps & PCI_AF_CAP_FLR) {
VIR_DEBUG("%s %s: detected PCI FLR capability", dev->id, dev->name);
return 1;
}
}
/* there are some buggy devices that do support FLR, but forget to
* advertise that fact in their capabilities. However, FLR is *required*
* to be present for virtual functions (VFs), so if we see that this
* device is a VF, we just assume FLR works
*/
if (virAsprintf(&path, PCI_SYSFS "devices/%s/physfn", dev->name) < 0) {
virReportOOMError();
return -1;
}
found = virFileExists(path);
VIR_FREE(path);
if (found) {
VIR_DEBUG("%s %s: buggy device didn't advertise FLR, but is a VF; forcing flr on",
dev->id, dev->name);
return 1;
}
VIR_DEBUG("%s %s: no FLR capability found", dev->id, dev->name);
return 0;
}
/* Require the device has the PCI Power Management capability
* and that a D3hot->D0 transition will results in a full
* internal reset, not just a soft reset.
*/
static unsigned
pciDetectPowerManagementReset(pciDevice *dev, int cfgfd)
{
if (dev->pci_pm_cap_pos) {
uint32_t ctl;
/* require the NO_SOFT_RESET bit is clear */
ctl = pciRead32(dev, cfgfd, dev->pci_pm_cap_pos + PCI_PM_CTRL);
if (!(ctl & PCI_PM_CTRL_NO_SOFT_RESET)) {
VIR_DEBUG("%s %s: detected PM reset capability", dev->id, dev->name);
return 1;
}
}
VIR_DEBUG("%s %s: no PM reset capability found", dev->id, dev->name);
return 0;
}
/* Any active devices on the same domain/bus ? */
static int
pciSharesBusWithActive(pciDevice *dev, pciDevice *check, void *data)
{
pciDeviceList *inactiveDevs = data;
/* Different domain, different bus, or simply identical device */
if (dev->domain != check->domain ||
dev->bus != check->bus ||
(dev->slot == check->slot &&
dev->function == check->function))
return 0;
/* same bus, but inactive, i.e. about to be assigned to guest */
if (inactiveDevs && pciDeviceListFind(inactiveDevs, check))
return 0;
return 1;
}
static pciDevice *
pciBusContainsActiveDevices(pciDevice *dev,
pciDeviceList *inactiveDevs)
{
pciDevice *active = NULL;
if (pciIterDevices(pciSharesBusWithActive,
dev, &active, inactiveDevs) < 0)
return NULL;
return active;
}
/* Is @check the parent of @dev ? */
static int
pciIsParent(pciDevice *dev, pciDevice *check, void *data)
{
uint16_t device_class;
uint8_t header_type, secondary, subordinate;
pciDevice **best = data;
int ret = 0;
int fd;
if (dev->domain != check->domain)
return 0;
if ((fd = pciConfigOpen(check, false)) < 0)
return 0;
/* Is it a bridge? */
device_class = pciRead16(check, fd, PCI_CLASS_DEVICE);
if (device_class != PCI_CLASS_BRIDGE_PCI)
goto cleanup;
/* Is it a plane? */
header_type = pciRead8(check, fd, PCI_HEADER_TYPE);
if ((header_type & PCI_HEADER_TYPE_MASK) != PCI_HEADER_TYPE_BRIDGE)
goto cleanup;
secondary = pciRead8(check, fd, PCI_SECONDARY_BUS);
subordinate = pciRead8(check, fd, PCI_SUBORDINATE_BUS);
VIR_DEBUG("%s %s: found parent device %s", dev->id, dev->name, check->name);
/* if the secondary bus exactly equals the device's bus, then we found
* the direct parent. No further work is necessary
*/
if (dev->bus == secondary) {
ret = 1;
goto cleanup;
}
/* otherwise, SRIOV allows VFs to be on different busses then their PFs.
* In this case, what we need to do is look for the "best" match; i.e.
* the most restrictive match that still satisfies all of the conditions.
*/
if (dev->bus > secondary && dev->bus <= subordinate) {
if (*best == NULL) {
*best = pciGetDevice(check->domain, check->bus, check->slot,
check->function);
if (*best == NULL) {
ret = -1;
goto cleanup;
}
} else {
/* OK, we had already recorded a previous "best" match for the
* parent. See if the current device is more restrictive than the
* best, and if so, make it the new best
*/
int bestfd;
uint8_t best_secondary;
if ((bestfd = pciConfigOpen(*best, false)) < 0)
goto cleanup;
best_secondary = pciRead8(*best, bestfd, PCI_SECONDARY_BUS);
pciConfigClose(*best, bestfd);
if (secondary > best_secondary) {
pciFreeDevice(*best);
*best = pciGetDevice(check->domain, check->bus, check->slot,
check->function);
if (*best == NULL) {
ret = -1;
goto cleanup;
}
}
}
}
cleanup:
pciConfigClose(check, fd);
return ret;
}
static int
pciGetParentDevice(pciDevice *dev, pciDevice **parent)
{
pciDevice *best = NULL;
int ret;
*parent = NULL;
ret = pciIterDevices(pciIsParent, dev, parent, &best);
if (ret == 1)
pciFreeDevice(best);
else if (ret == 0)
*parent = best;
return ret;
}
/* Secondary Bus Reset is our sledgehammer - it resets all
* devices behind a bus.
*/
static int
pciTrySecondaryBusReset(pciDevice *dev,
int cfgfd,
pciDeviceList *inactiveDevs)
{
pciDevice *parent, *conflict;
uint8_t config_space[PCI_CONF_LEN];
uint16_t ctl;
int ret = -1;
int parentfd;
/* Refuse to do a secondary bus reset if there are other
* devices/functions behind the bus are used by the host
* or other guests.
*/
if ((conflict = pciBusContainsActiveDevices(dev, inactiveDevs))) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Active %s devices on bus with %s, not doing bus reset"),
conflict->name, dev->name);
return -1;
}
/* Find the parent bus */
if (pciGetParentDevice(dev, &parent) < 0)
return -1;
if (!parent) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Failed to find parent device for %s"),
dev->name);
return -1;
}
if ((parentfd = pciConfigOpen(parent, true)) < 0)
goto out;
VIR_DEBUG("%s %s: doing a secondary bus reset", dev->id, dev->name);
/* Save and restore the device's config space; we only do this
* for the supplied device since we refuse to do a reset if there
* are multiple devices/functions
*/
if (pciRead(dev, cfgfd, 0, config_space, PCI_CONF_LEN) < 0) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Failed to read PCI config space for %s"),
dev->name);
goto out;
}
/* Read the control register, set the reset flag, wait 200ms,
* unset the reset flag and wait 200ms.
*/
ctl = pciRead16(dev, cfgfd, PCI_BRIDGE_CONTROL);
pciWrite16(parent, parentfd, PCI_BRIDGE_CONTROL,
ctl | PCI_BRIDGE_CTL_RESET);
usleep(200 * 1000); /* sleep 200ms */
pciWrite16(parent, parentfd, PCI_BRIDGE_CONTROL, ctl);
usleep(200 * 1000); /* sleep 200ms */
if (pciWrite(dev, cfgfd, 0, config_space, PCI_CONF_LEN) < 0) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Failed to restore PCI config space for %s"),
dev->name);
goto out;
}
ret = 0;
out:
pciConfigClose(parent, parentfd);
pciFreeDevice(parent);
return ret;
}
/* Power management reset attempts to reset a device using a
* D-state transition from D3hot to D0. Note, in detect_pm_reset()
* above we require the device supports a full internal reset.
*/
static int
pciTryPowerManagementReset(pciDevice *dev, int cfgfd)
{
uint8_t config_space[PCI_CONF_LEN];
uint32_t ctl;
if (!dev->pci_pm_cap_pos)
return -1;
/* Save and restore the device's config space. */
if (pciRead(dev, cfgfd, 0, &config_space[0], PCI_CONF_LEN) < 0) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Failed to read PCI config space for %s"),
dev->name);
return -1;
}
VIR_DEBUG("%s %s: doing a power management reset", dev->id, dev->name);
ctl = pciRead32(dev, cfgfd, dev->pci_pm_cap_pos + PCI_PM_CTRL);
ctl &= ~PCI_PM_CTRL_STATE_MASK;
pciWrite32(dev, cfgfd, dev->pci_pm_cap_pos + PCI_PM_CTRL,
ctl | PCI_PM_CTRL_STATE_D3hot);
usleep(10 * 1000); /* sleep 10ms */
pciWrite32(dev, cfgfd, dev->pci_pm_cap_pos + PCI_PM_CTRL,
ctl | PCI_PM_CTRL_STATE_D0);
usleep(10 * 1000); /* sleep 10ms */
if (pciWrite(dev, cfgfd, 0, &config_space[0], PCI_CONF_LEN) < 0) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Failed to restore PCI config space for %s"),
dev->name);
return -1;
}
return 0;
}
static int
pciInitDevice(pciDevice *dev, int cfgfd)
{
int flr;
dev->pcie_cap_pos = pciFindCapabilityOffset(dev, cfgfd, PCI_CAP_ID_EXP);
dev->pci_pm_cap_pos = pciFindCapabilityOffset(dev, cfgfd, PCI_CAP_ID_PM);
flr = pciDetectFunctionLevelReset(dev, cfgfd);
if (flr < 0)
return flr;
dev->has_flr = flr;
dev->has_pm_reset = pciDetectPowerManagementReset(dev, cfgfd);
return 0;
}
int
pciResetDevice(pciDevice *dev,
pciDeviceList *activeDevs,
pciDeviceList *inactiveDevs)
{
int ret = -1;
int fd;
if (activeDevs && pciDeviceListFind(activeDevs, dev)) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Not resetting active device %s"), dev->name);
return -1;
}
if ((fd = pciConfigOpen(dev, true)) < 0)
return -1;
if (pciInitDevice(dev, fd) < 0)
goto cleanup;
/* KVM will perform FLR when starting and stopping
* a guest, so there is no need for us to do it here.
*/
if (dev->has_flr) {
ret = 0;
goto cleanup;
}
/* If the device supports PCI power management reset,
* that's the next best thing because it only resets
* the function, not the whole device.
*/
if (dev->has_pm_reset)
ret = pciTryPowerManagementReset(dev, fd);
/* Bus reset is not an option with the root bus */
if (ret < 0 && dev->bus != 0)
ret = pciTrySecondaryBusReset(dev, fd, inactiveDevs);
if (ret < 0) {
virErrorPtr err = virGetLastError();
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Unable to reset PCI device %s: %s"),
dev->name,
err ? err->message : _("no FLR, PM reset or bus reset available"));
}
cleanup:
pciConfigClose(dev, fd);
return ret;
}
static int
pciDriverDir(char **buffer, const char *driver)
{
VIR_FREE(*buffer);
if (virAsprintf(buffer, PCI_SYSFS "drivers/%s", driver) < 0) {
virReportOOMError();
return -1;
}
return 0;
}
static int
pciDriverFile(char **buffer, const char *driver, const char *file)
{
VIR_FREE(*buffer);
if (virAsprintf(buffer, PCI_SYSFS "drivers/%s/%s", driver, file) < 0) {
virReportOOMError();
return -1;
}
return 0;
}
static int
pciDeviceFile(char **buffer, const char *device, const char *file)
{
VIR_FREE(*buffer);
if (virAsprintf(buffer, PCI_SYSFS "devices/%s/%s", device, file) < 0) {
virReportOOMError();
return -1;
}
return 0;
}
static int
pciProbeStubDriver(const char *driver)
{
char *drvpath = NULL;
int probed = 0;
recheck:
if (pciDriverDir(&drvpath, driver) == 0 && virFileExists(drvpath)) {
/* driver already loaded, return */
VIR_FREE(drvpath);
return 0;
}
VIR_FREE(drvpath);
if (!probed) {
const char *const probecmd[] = { MODPROBE, driver, NULL };
probed = 1;
if (virRun(probecmd, NULL) < 0) {
char ebuf[1024];
VIR_WARN("failed to load driver %s: %s", driver,
virStrerror(errno, ebuf, sizeof(ebuf)));
return -1;
}
goto recheck;
}
return -1;
}
static int
pciUnbindDeviceFromStub(pciDevice *dev, const char *driver)
{
int result = -1;
char *drvdir = NULL;
char *path = NULL;
if (pciDriverDir(&drvdir, driver) < 0)
goto cleanup;
if (!dev->unbind_from_stub)
goto remove_slot;
/* If the device is bound to stub, unbind it.
*/
if (pciDeviceFile(&path, dev->name, "driver") < 0)
goto cleanup;
if (virFileExists(drvdir) && virFileLinkPointsTo(path, drvdir)) {
if (pciDriverFile(&path, driver, "unbind") < 0) {
goto cleanup;
}
if (virFileWriteStr(path, dev->name, 0) < 0) {
virReportSystemError(errno,
_("Failed to unbind PCI device '%s' from %s"),
dev->name, driver);
goto cleanup;
}
}
dev->unbind_from_stub = 0;
remove_slot:
if (!dev->remove_slot)
goto reprobe;
/* Xen's pciback.ko wants you to use remove_slot on the specific device */
if (pciDriverFile(&path, driver, "remove_slot") < 0) {
goto cleanup;
}
if (virFileExists(path) && virFileWriteStr(path, dev->name, 0) < 0) {
virReportSystemError(errno,
_("Failed to remove slot for PCI device '%s' from %s"),
dev->name, driver);
goto cleanup;
}
dev->remove_slot = 0;
reprobe:
if (!dev->reprobe) {
result = 0;
goto cleanup;
}
/* Trigger a re-probe of the device is not in the stub's dynamic
* ID table. If the stub is available, but 'remove_id' isn't
* available, then re-probing would just cause the device to be
* re-bound to the stub.
*/
if (pciDriverFile(&path, driver, "remove_id") < 0) {
goto cleanup;
}
if (!virFileExists(drvdir) || virFileExists(path)) {
if (virFileWriteStr(PCI_SYSFS "drivers_probe", dev->name, 0) < 0) {
virReportSystemError(errno,
_("Failed to trigger a re-probe for PCI device '%s'"),
dev->name);
goto cleanup;
}
}
result = 0;
cleanup:
/* do not do it again */
dev->unbind_from_stub = 0;
dev->remove_slot = 0;
dev->reprobe = 0;
VIR_FREE(drvdir);
VIR_FREE(path);
return result;
}
static int
pciBindDeviceToStub(pciDevice *dev, const char *driver)
{
int result = -1;
char *drvdir = NULL;
char *path = NULL;
int reprobe = 0;
/* check whether the device is already bound to a driver */
if (pciDriverDir(&drvdir, driver) < 0 ||
pciDeviceFile(&path, dev->name, "driver") < 0) {
goto cleanup;
}
if (virFileExists(path)) {
if (virFileLinkPointsTo(path, drvdir)) {
/* The device is already bound to pci-stub */
result = 0;
goto cleanup;
}
reprobe = 1;
}
/* Add the PCI device ID to the stub's dynamic ID table;
* this is needed to allow us to bind the device to the stub.
* Note: if the device is not currently bound to any driver,
* stub will immediately be bound to the device. Also, note
* that if a new device with this ID is hotplugged, or if a probe
* is triggered for such a device, it will also be immediately
* bound by the stub.
*/
if (pciDriverFile(&path, driver, "new_id") < 0) {
goto cleanup;
}
if (virFileWriteStr(path, dev->id, 0) < 0) {
virReportSystemError(errno,
_("Failed to add PCI device ID '%s' to %s"),
dev->id, driver);
goto cleanup;
}
/* check whether the device is bound to pci-stub when we write dev->id to
* new_id.
*/
if (pciDriverDir(&drvdir, driver) < 0 ||
pciDeviceFile(&path, dev->name, "driver") < 0) {
goto remove_id;
}
if (virFileLinkPointsTo(path, drvdir)) {
dev->unbind_from_stub = 1;
dev->remove_slot = 1;
goto remove_id;
}
/* If the device is already bound to a driver, unbind it.
* Note, this will have rather unpleasant side effects if this
* PCI device happens to be IDE controller for the disk hosting
* your root filesystem.
*/
if (pciDeviceFile(&path, dev->name, "driver/unbind") < 0) {
goto cleanup;
}
if (virFileExists(path)) {
if (virFileWriteStr(path, dev->name, 0) < 0) {
virReportSystemError(errno,
_("Failed to unbind PCI device '%s'"),
dev->name);
goto cleanup;
}
dev->reprobe = reprobe;
}
/* If the device isn't already bound to pci-stub, try binding it now.
*/
if (pciDriverDir(&drvdir, driver) < 0 ||
pciDeviceFile(&path, dev->name, "driver") < 0) {
goto remove_id;
}
if (!virFileLinkPointsTo(path, drvdir)) {
/* Xen's pciback.ko wants you to use new_slot first */
if (pciDriverFile(&path, driver, "new_slot") < 0) {
goto remove_id;
}
if (virFileExists(path) && virFileWriteStr(path, dev->name, 0) < 0) {
virReportSystemError(errno,
_("Failed to add slot for PCI device '%s' to %s"),
dev->name, driver);
goto remove_id;
}
dev->remove_slot = 1;
if (pciDriverFile(&path, driver, "bind") < 0) {
goto remove_id;
}
if (virFileWriteStr(path, dev->name, 0) < 0) {
virReportSystemError(errno,
_("Failed to bind PCI device '%s' to %s"),
dev->name, driver);
goto remove_id;
}
dev->unbind_from_stub = 1;
}
remove_id:
/* If 'remove_id' exists, remove the device id from pci-stub's dynamic
* ID table so that 'drivers_probe' works below.
*/
if (pciDriverFile(&path, driver, "remove_id") < 0) {
/* We do not remove PCI ID from pci-stub, and we cannot reprobe it */
if (dev->reprobe) {
VIR_WARN("Could not remove PCI ID '%s' from %s, and the device "
"cannot be probed again.", dev->id, driver);
}
dev->reprobe = 0;
goto cleanup;
}
if (virFileExists(path) && virFileWriteStr(path, dev->id, 0) < 0) {
virReportSystemError(errno,
_("Failed to remove PCI ID '%s' from %s"),
dev->id, driver);
/* remove PCI ID from pci-stub failed, and we cannot reprobe it */
if (dev->reprobe) {
VIR_WARN("Failed to remove PCI ID '%s' from %s, and the device "
"cannot be probed again.", dev->id, driver);
}
dev->reprobe = 0;
goto cleanup;
}
result = 0;
cleanup:
VIR_FREE(drvdir);
VIR_FREE(path);
if (result < 0) {
pciUnbindDeviceFromStub(dev, driver);
}
return result;
}
int
pciDettachDevice(pciDevice *dev,
pciDeviceList *activeDevs,
pciDeviceList *inactiveDevs,
const char *driver)
{
if (pciProbeStubDriver(driver) < 0) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Failed to load PCI stub module %s"), driver);
return -1;
}
if (activeDevs && pciDeviceListFind(activeDevs, dev)) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Not detaching active device %s"), dev->name);
return -1;
}
if (pciBindDeviceToStub(dev, driver) < 0)
return -1;
/* Add the dev into list inactiveDevs */
if (inactiveDevs && !pciDeviceListFind(inactiveDevs, dev)) {
if (pciDeviceListAdd(inactiveDevs, dev) < 0)
return -1;
}
return 0;
}
int
pciReAttachDevice(pciDevice *dev,
pciDeviceList *activeDevs,
pciDeviceList *inactiveDevs,
const char *driver)
{
if (pciProbeStubDriver(driver) < 0) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Failed to load PCI stub module %s"), driver);
return -1;
}
if (activeDevs && pciDeviceListFind(activeDevs, dev)) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Not reattaching active device %s"), dev->name);
return -1;
}
if (pciUnbindDeviceFromStub(dev, driver) < 0)
return -1;
/* Steal the dev from list inactiveDevs */
if (inactiveDevs)
pciDeviceListSteal(inactiveDevs, dev);
return 0;
}
/* Certain hypervisors (like qemu/kvm) map the PCI bar(s) on
* the host when doing device passthrough. This can lead to a race
* condition where the hypervisor is still cleaning up the device while
* libvirt is trying to re-attach it to the host device driver. To avoid
* this situation, we look through /proc/iomem, and if the hypervisor is
* still holding onto the bar (denoted by the string in the matcher variable),
* then we can wait around a bit for that to clear up.
*
* A typical /proc/iomem looks like this (snipped for brevity):
* 00010000-0008efff : System RAM
* 0008f000-0008ffff : reserved
* ...
* 00100000-cc9fcfff : System RAM
* 00200000-00483d3b : Kernel code
* 00483d3c-005c88df : Kernel data
* cc9fd000-ccc71fff : ACPI Non-volatile Storage
* ...
* d0200000-d02fffff : PCI Bus #05
* d0200000-d021ffff : 0000:05:00.0
* d0200000-d021ffff : e1000e
* d0220000-d023ffff : 0000:05:00.0
* d0220000-d023ffff : e1000e
* ...
* f0000000-f0003fff : 0000:00:1b.0
* f0000000-f0003fff : kvm_assigned_device
*
* Returns 0 if we are clear to continue, and 1 if the hypervisor is still
* holding onto the resource.
*/
int
pciWaitForDeviceCleanup(pciDevice *dev, const char *matcher)
{
FILE *fp;
char line[160];
char *tmp;
unsigned long long start, end;
unsigned int domain, bus, slot, function;
int in_matching_device;
int ret;
size_t match_depth;
fp = fopen("/proc/iomem", "r");
if (!fp) {
/* If we failed to open iomem, we just basically ignore the error. The
* unbind might succeed anyway, and besides, it's very likely we have
* no way to report the error
*/
VIR_DEBUG("Failed to open /proc/iomem, trying to continue anyway");
return 0;
}
ret = 0;
in_matching_device = 0;
match_depth = 0;
while (fgets(line, sizeof(line), fp) != 0) {
/* the logic here is a bit confusing. For each line, we look to
* see if it matches the domain:bus:slot.function we were given.
* If this line matches the DBSF, then any subsequent lines indented
* by 2 spaces are the PCI regions for this device. It's also
* possible that none of the PCI regions are currently mapped, in
* which case we have no indented regions. This code handles all
* of these situations
*/
if (in_matching_device && (strspn(line, " ") == (match_depth + 2))) {
/* expected format: <start>-<end> : <suffix> */
if (/* start */
virStrToLong_ull(line, &tmp, 16, &start) < 0 || *tmp != '-' ||
/* end */
virStrToLong_ull(tmp + 1, &tmp, 16, &end) < 0 ||
(tmp = STRSKIP(tmp, " : ")) == NULL)
continue;
if (STRPREFIX(tmp, matcher)) {
ret = 1;
break;
}
}
else {
in_matching_device = 0;
/* expected format: <start>-<end> : <domain>:<bus>:<slot>.<function> */
if (/* start */
virStrToLong_ull(line, &tmp, 16, &start) < 0 || *tmp != '-' ||
/* end */
virStrToLong_ull(tmp + 1, &tmp, 16, &end) < 0 ||
(tmp = STRSKIP(tmp, " : ")) == NULL ||
/* domain */
virStrToLong_ui(tmp, &tmp, 16, &domain) < 0 || *tmp != ':' ||
/* bus */
virStrToLong_ui(tmp + 1, &tmp, 16, &bus) < 0 || *tmp != ':' ||
/* slot */
virStrToLong_ui(tmp + 1, &tmp, 16, &slot) < 0 || *tmp != '.' ||
/* function */
virStrToLong_ui(tmp + 1, &tmp, 16, &function) < 0 || *tmp != '\n')
continue;
if (domain != dev->domain || bus != dev->bus || slot != dev->slot ||
function != dev->function)
continue;
in_matching_device = 1;
match_depth = strspn(line, " ");
}
}
VIR_FORCE_FCLOSE(fp);
return ret;
}
static char *
pciReadDeviceID(pciDevice *dev, const char *id_name)
{
char *path = NULL;
char *id_str;
if (pciDeviceFile(&path, dev->name, id_name) < 0) {
return NULL;
}
/* ID string is '0xNNNN\n' ... i.e. 7 bytes */
if (virFileReadAll(path, 7, &id_str) < 0) {
VIR_FREE(path);
return NULL;
}
VIR_FREE(path);
/* Check for 0x suffix */
if (id_str[0] != '0' || id_str[1] != 'x') {
VIR_FREE(id_str);
return NULL;
}
/* Chop off the newline; we know the string is 7 bytes */
id_str[6] = '\0';
return id_str;
}
int
pciGetDeviceAddrString(unsigned domain,
unsigned bus,
unsigned slot,
unsigned function,
char **pciConfigAddr)
{
pciDevice *dev = NULL;
int ret = -1;
dev = pciGetDevice(domain, bus, slot, function);
if (dev != NULL) {
if ((*pciConfigAddr = strdup(dev->name)) == NULL) {
virReportOOMError();
goto cleanup;
}
ret = 0;
}
cleanup:
pciFreeDevice(dev);
return ret;
}
pciDevice *
pciGetDevice(unsigned domain,
unsigned bus,
unsigned slot,
unsigned function)
{
pciDevice *dev;
char *vendor = NULL;
char *product = NULL;
if (VIR_ALLOC(dev) < 0) {
virReportOOMError();
return NULL;
}
dev->domain = domain;
dev->bus = bus;
dev->slot = slot;
dev->function = function;
if (snprintf(dev->name, sizeof(dev->name), "%.4x:%.2x:%.2x.%.1x",
dev->domain, dev->bus, dev->slot,
dev->function) >= sizeof(dev->name)) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("dev->name buffer overflow: %.4x:%.2x:%.2x.%.1x"),
dev->domain, dev->bus, dev->slot, dev->function);
goto error;
}
if (virAsprintf(&dev->path, PCI_SYSFS "devices/%s/config",
dev->name) < 0) {
virReportOOMError();
goto error;
}
if (access(dev->path, F_OK) != 0) {
virReportSystemError(errno,
_("Device %s not found: could not access %s"),
dev->name, dev->path);
goto error;
}
vendor = pciReadDeviceID(dev, "vendor");
product = pciReadDeviceID(dev, "device");
if (!vendor || !product) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Failed to read product/vendor ID for %s"),
dev->name);
goto error;
}
/* strings contain '0x' prefix */
if (snprintf(dev->id, sizeof(dev->id), "%s %s", &vendor[2],
&product[2]) >= sizeof(dev->id)) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("dev->id buffer overflow: %s %s"),
&vendor[2], &product[2]);
goto error;
}
VIR_DEBUG("%s %s: initialized", dev->id, dev->name);
cleanup:
VIR_FREE(product);
VIR_FREE(vendor);
return dev;
error:
pciFreeDevice(dev);
dev = NULL;
goto cleanup;
}
void
pciFreeDevice(pciDevice *dev)
{
if (!dev)
return;
VIR_DEBUG("%s %s: freeing", dev->id, dev->name);
VIR_FREE(dev->path);
VIR_FREE(dev);
}
const char *
pciDeviceGetName(pciDevice *dev)
{
return dev->name;
}
void pciDeviceSetManaged(pciDevice *dev, unsigned managed)
{
dev->managed = !!managed;
}
unsigned pciDeviceGetManaged(pciDevice *dev)
{
return dev->managed;
}
unsigned
pciDeviceGetUnbindFromStub(pciDevice *dev)
{
return dev->unbind_from_stub;
}
void
pciDeviceSetUnbindFromStub(pciDevice *dev, unsigned unbind)
{
dev->unbind_from_stub = !!unbind;
}
unsigned
pciDeviceGetRemoveSlot(pciDevice *dev)
{
return dev->remove_slot;
}
void
pciDeviceSetRemoveSlot(pciDevice *dev, unsigned remove_slot)
{
dev->remove_slot = !!remove_slot;
}
unsigned
pciDeviceGetReprobe(pciDevice *dev)
{
return dev->reprobe;
}
void
pciDeviceSetReprobe(pciDevice *dev, unsigned reprobe)
{
dev->reprobe = !!reprobe;
}
void
pciDeviceSetUsedBy(pciDevice *dev, const char *name)
{
dev->used_by = name;
}
const char *
pciDeviceGetUsedBy(pciDevice *dev)
{
return dev->used_by;
}
void pciDeviceReAttachInit(pciDevice *pci)
{
pci->unbind_from_stub = 1;
pci->remove_slot = 1;
pci->reprobe = 1;
}
pciDeviceList *
pciDeviceListNew(void)
{
pciDeviceList *list;
if (VIR_ALLOC(list) < 0) {
virReportOOMError();
return NULL;
}
return list;
}
void
pciDeviceListFree(pciDeviceList *list)
{
int i;
if (!list)
return;
for (i = 0; i < list->count; i++) {
pciFreeDevice(list->devs[i]);
list->devs[i] = NULL;
}
list->count = 0;
VIR_FREE(list->devs);
VIR_FREE(list);
}
int
pciDeviceListAdd(pciDeviceList *list,
pciDevice *dev)
{
if (pciDeviceListFind(list, dev)) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Device %s is already in use"), dev->name);
return -1;
}
if (VIR_REALLOC_N(list->devs, list->count+1) < 0) {
virReportOOMError();
return -1;
}
list->devs[list->count++] = dev;
return 0;
}
pciDevice *
pciDeviceListGet(pciDeviceList *list,
int idx)
{
if (idx >= list->count)
return NULL;
if (idx < 0)
return NULL;
return list->devs[idx];
}
int
pciDeviceListCount(pciDeviceList *list)
{
return list->count;
}
pciDevice *
pciDeviceListStealIndex(pciDeviceList *list,
int idx)
{
pciDevice *ret;
if (idx < 0 || idx >= list->count)
return NULL;
ret = list->devs[idx];
if (idx != --list->count) {
memmove(&list->devs[idx],
&list->devs[idx + 1],
sizeof(*list->devs) * (list->count - idx));
}
if (VIR_REALLOC_N(list->devs, list->count) < 0) {
; /* not fatal */
}
return ret;
}
pciDevice *
pciDeviceListSteal(pciDeviceList *list,
pciDevice *dev)
{
return pciDeviceListStealIndex(list, pciDeviceListFindIndex(list, dev));
}
void
pciDeviceListDel(pciDeviceList *list,
pciDevice *dev)
{
pciDevice *ret = pciDeviceListSteal(list, dev);
if (ret)
pciFreeDevice(ret);
}
int
pciDeviceListFindIndex(pciDeviceList *list, pciDevice *dev)
{
int i;
for (i = 0; i < list->count; i++)
if (list->devs[i]->domain == dev->domain &&
list->devs[i]->bus == dev->bus &&
list->devs[i]->slot == dev->slot &&
list->devs[i]->function == dev->function)
return i;
return -1;
}
pciDevice *
pciDeviceListFind(pciDeviceList *list, pciDevice *dev)
{
int i;
if ((i = pciDeviceListFindIndex(list, dev)) >= 0)
return list->devs[i];
else
return NULL;
}
int pciDeviceFileIterate(pciDevice *dev,
pciDeviceFileActor actor,
void *opaque)
{
char *pcidir = NULL;
char *file = NULL;
DIR *dir = NULL;
int ret = -1;
struct dirent *ent;
if (virAsprintf(&pcidir, "/sys/bus/pci/devices/%04x:%02x:%02x.%x",
dev->domain, dev->bus, dev->slot, dev->function) < 0) {
virReportOOMError();
goto cleanup;
}
if (!(dir = opendir(pcidir))) {
virReportSystemError(errno,
_("cannot open %s"), pcidir);
goto cleanup;
}
while ((ent = readdir(dir)) != NULL) {
/* Device assignment requires:
* $PCIDIR/config, $PCIDIR/resource, $PCIDIR/resourceNNN,
* $PCIDIR/rom, $PCIDIR/reset
*/
if (STREQ(ent->d_name, "config") ||
STRPREFIX(ent->d_name, "resource") ||
STREQ(ent->d_name, "rom") ||
STREQ(ent->d_name, "reset")) {
if (virAsprintf(&file, "%s/%s", pcidir, ent->d_name) < 0) {
virReportOOMError();
goto cleanup;
}
if ((actor)(dev, file, opaque) < 0)
goto cleanup;
VIR_FREE(file);
}
}
ret = 0;
cleanup:
if (dir)
closedir(dir);
VIR_FREE(file);
VIR_FREE(pcidir);
return ret;
}
static int
pciDeviceDownstreamLacksACS(pciDevice *dev)
{
uint16_t flags;
uint16_t ctrl;
unsigned int pos;
int fd;
int ret = 0;
if ((fd = pciConfigOpen(dev, true)) < 0)
return -1;
if (pciInitDevice(dev, fd) < 0) {
ret = -1;
goto cleanup;
}
pos = dev->pcie_cap_pos;
if (!pos || pciRead16(dev, fd, PCI_CLASS_DEVICE) != PCI_CLASS_BRIDGE_PCI)
goto cleanup;
flags = pciRead16(dev, fd, pos + PCI_EXP_FLAGS);
if (((flags & PCI_EXP_FLAGS_TYPE) >> 4) != PCI_EXP_TYPE_DOWNSTREAM)
goto cleanup;
pos = pciFindExtendedCapabilityOffset(dev, fd, PCI_EXT_CAP_ID_ACS);
if (!pos) {
VIR_DEBUG("%s %s: downstream port lacks ACS", dev->id, dev->name);
ret = 1;
goto cleanup;
}
ctrl = pciRead16(dev, fd, pos + PCI_EXT_ACS_CTRL);
if ((ctrl & PCI_EXT_CAP_ACS_ENABLED) != PCI_EXT_CAP_ACS_ENABLED) {
VIR_DEBUG("%s %s: downstream port has ACS disabled",
dev->id, dev->name);
ret = 1;
goto cleanup;
}
cleanup:
pciConfigClose(dev, fd);
return ret;
}
static int
pciDeviceIsBehindSwitchLackingACS(pciDevice *dev)
{
pciDevice *parent;
if (pciGetParentDevice(dev, &parent) < 0)
return -1;
if (!parent) {
/* if we have no parent, and this is the root bus, ACS doesn't come
* into play since devices on the root bus can't P2P without going
* through the root IOMMU.
*/
if (dev->bus == 0)
return 0;
else {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Failed to find parent device for %s"),
dev->name);
return -1;
}
}
/* XXX we should rather fail when we can't find device's parent and
* stop the loop when we get to root instead of just stopping when no
* parent can be found
*/
do {
pciDevice *tmp;
int acs;
int ret;
acs = pciDeviceDownstreamLacksACS(parent);
if (acs) {
pciFreeDevice(parent);
if (acs < 0)
return -1;
else
return 1;
}
tmp = parent;
ret = pciGetParentDevice(parent, &parent);
pciFreeDevice(tmp);
if (ret < 0)
return -1;
} while (parent);
return 0;
}
int pciDeviceIsAssignable(pciDevice *dev,
int strict_acs_check)
{
int ret;
/* XXX This could be a great place to actually check that a non-managed
* device isn't in use, e.g. by checking that device is either un-bound
* or bound to a stub driver.
*/
ret = pciDeviceIsBehindSwitchLackingACS(dev);
if (ret < 0)
return 0;
if (ret) {
if (!strict_acs_check) {
VIR_DEBUG("%s %s: strict ACS check disabled; device assignment allowed",
dev->id, dev->name);
} else {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Device %s is behind a switch lacking ACS and "
"cannot be assigned"),
dev->name);
return 0;
}
}
return 1;
}
#ifdef __linux__
/*
* returns true if equal
*/
static bool
pciConfigAddressEqual(struct pci_config_address *bdf1,
struct pci_config_address *bdf2)
{
return ((bdf1->domain == bdf2->domain) &&
(bdf1->bus == bdf2->bus) &&
(bdf1->slot == bdf2->slot) &&
(bdf1->function == bdf2->function));
}
static int
logStrToLong_ui(char const *s,
char **end_ptr,
int base,
unsigned int *result)
{
int ret = 0;
ret = virStrToLong_ui(s, end_ptr, base, result);
if (ret != 0) {
VIR_ERROR(_("Failed to convert '%s' to unsigned int"), s);
} else {
VIR_DEBUG("Converted '%s' to unsigned int %u", s, *result);
}
return ret;
}
static int
pciParsePciConfigAddress(char *address,
struct pci_config_address *bdf)
{
char *p = NULL;
int ret = -1;
if ((address == NULL) || (logStrToLong_ui(address, &p, 16,
&bdf->domain) == -1)) {
goto out;
}
if ((p == NULL) || (logStrToLong_ui(p+1, &p, 16,
&bdf->bus) == -1)) {
goto out;
}
if ((p == NULL) || (logStrToLong_ui(p+1, &p, 16,
&bdf->slot) == -1)) {
goto out;
}
if ((p == NULL) || (logStrToLong_ui(p+1, &p, 16,
&bdf->function) == -1)) {
goto out;
}
ret = 0;
out:
return ret;
}
static int
pciGetPciConfigAddressFromSysfsDeviceLink(const char *device_link,
struct pci_config_address **bdf)
{
char *config_address = NULL;
char *device_path = NULL;
char errbuf[64];
int ret = -1;
VIR_DEBUG("Attempting to resolve device path from device link '%s'",
device_link);
if (!virFileExists(device_link)) {
VIR_DEBUG("sysfs_path '%s' does not exist", device_link);
return ret;
}
device_path = canonicalize_file_name(device_link);
if (device_path == NULL) {
memset(errbuf, '\0', sizeof(errbuf));
virReportSystemError(errno,
_("Failed to resolve device link '%s'"),
device_link);
return ret;
}
config_address = basename(device_path);
if (VIR_ALLOC(*bdf) != 0) {
virReportOOMError();
goto out;
}
if (pciParsePciConfigAddress(config_address, *bdf) != 0) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Failed to parse PCI config address '%s'"),
config_address);
VIR_FREE(*bdf);
goto out;
}
VIR_DEBUG("pci_config_address %.4x:%.2x:%.2x.%.1x",
(*bdf)->domain,
(*bdf)->bus,
(*bdf)->slot,
(*bdf)->function);
ret = 0;
out:
VIR_FREE(device_path);
return ret;
}
/*
* Returns Physical function given a virtual function
*/
int
pciGetPhysicalFunction(const char *vf_sysfs_path,
struct pci_config_address **physical_function)
{
int ret = -1;
char *device_link = NULL;
VIR_DEBUG("Attempting to get SR IOV physical function for device "
"with sysfs path '%s'", vf_sysfs_path);
if (virBuildPath(&device_link, vf_sysfs_path, "physfn") == -1) {
virReportOOMError();
return ret;
} else {
ret = pciGetPciConfigAddressFromSysfsDeviceLink(device_link,
physical_function);
}
VIR_FREE(device_link);
return ret;
}
/*
* Returns virtual functions of a physical function
*/
int
pciGetVirtualFunctions(const char *sysfs_path,
struct pci_config_address ***virtual_functions,
unsigned int *num_virtual_functions)
{
int ret = -1;
DIR *dir = NULL;
struct dirent *entry = NULL;
char *device_link = NULL;
char errbuf[64];
VIR_DEBUG("Attempting to get SR IOV virtual functions for device"
"with sysfs path '%s'", sysfs_path);
dir = opendir(sysfs_path);
if (dir == NULL) {
memset(errbuf, '\0', sizeof(errbuf));
virReportSystemError(errno,
_("Failed to open dir '%s'"),
sysfs_path);
return ret;
}
*virtual_functions = NULL;
*num_virtual_functions = 0;
while ((entry = readdir(dir))) {
if (STRPREFIX(entry->d_name, "virtfn")) {
if (virBuildPath(&device_link, sysfs_path, entry->d_name) == -1) {
virReportOOMError();
goto out;
}
VIR_DEBUG("Number of virtual functions: %d",
*num_virtual_functions);
if (VIR_REALLOC_N(*virtual_functions,
(*num_virtual_functions) + 1) != 0) {
virReportOOMError();
VIR_FREE(device_link);
goto out;
}
if (pciGetPciConfigAddressFromSysfsDeviceLink(device_link,
&((*virtual_functions)[*num_virtual_functions])) !=
SRIOV_FOUND) {
/* We should not get back SRIOV_NOT_FOUND in this
* case, so if we do, it's an error. */
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Failed to get SR IOV function from device "
"link '%s'"), device_link);
VIR_FREE(device_link);
goto out;
} else {
(*num_virtual_functions)++;
}
VIR_FREE(device_link);
}
}
ret = 0;
out:
if (dir)
closedir(dir);
return ret;
}
/*
* Returns 1 if vf device is a virtual function, 0 if not, -1 on error
*/
int
pciDeviceIsVirtualFunction(const char *vf_sysfs_device_link)
{
char *vf_sysfs_physfn_link = NULL;
int ret = -1;
if (virAsprintf(&vf_sysfs_physfn_link, "%s/physfn",
vf_sysfs_device_link) < 0) {
virReportOOMError();
return ret;
}
ret = virFileExists(vf_sysfs_physfn_link);
VIR_FREE(vf_sysfs_physfn_link);
return ret;
}
/*
* Returns the sriov virtual function index of vf given its pf
*/
int
pciGetVirtualFunctionIndex(const char *pf_sysfs_device_link,
const char *vf_sysfs_device_link,
int *vf_index)
{
int ret = -1, i;
unsigned int num_virt_fns = 0;
struct pci_config_address *vf_bdf = NULL;
struct pci_config_address **virt_fns = NULL;
if (pciGetPciConfigAddressFromSysfsDeviceLink(vf_sysfs_device_link,
&vf_bdf) < 0)
return ret;
if (pciGetVirtualFunctions(pf_sysfs_device_link, &virt_fns,
&num_virt_fns) < 0) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Error getting physical function's '%s' "
"virtual_functions"), pf_sysfs_device_link);
goto out;
}
for (i = 0; i < num_virt_fns; i++) {
if (pciConfigAddressEqual(vf_bdf, virt_fns[i])) {
*vf_index = i;
ret = 0;
break;
}
}
out:
/* free virtual functions */
for (i = 0; i < num_virt_fns; i++)
VIR_FREE(virt_fns[i]);
VIR_FREE(virt_fns);
VIR_FREE(vf_bdf);
return ret;
}
/*
* Returns a path to the PCI sysfs file given the BDF of the PCI function
*/
int
pciSysfsFile(char *pciDeviceName, char **pci_sysfs_device_link)
{
if (virAsprintf(pci_sysfs_device_link, PCI_SYSFS "devices/%s",
pciDeviceName) < 0) {
virReportOOMError();
return -1;
}
return 0;
}
int
pciConfigAddressToSysfsFile(struct pci_config_address *dev,
char **pci_sysfs_device_link)
{
if (virAsprintf(pci_sysfs_device_link,
PCI_SYSFS "devices/%04x:%02x:%02x.%x", dev->domain,
dev->bus, dev->slot, dev->function) < 0) {
virReportOOMError();
return -1;
}
return 0;
}
/*
* Returns the network device name of a pci device
*/
int
pciDeviceNetName(char *device_link_sysfs_path, char **netname)
{
char *pcidev_sysfs_net_path = NULL;
int ret = -1;
DIR *dir = NULL;
struct dirent *entry = NULL;
if (virBuildPath(&pcidev_sysfs_net_path, device_link_sysfs_path,
"net") == -1) {
virReportOOMError();
return -1;
}
dir = opendir(pcidev_sysfs_net_path);
if (dir == NULL)
goto out;
while ((entry = readdir(dir))) {
if (STREQ(entry->d_name, ".") ||
STREQ(entry->d_name, ".."))
continue;
/* Assume a single directory entry */
*netname = strdup(entry->d_name);
if (!*netname)
virReportOOMError();
else
ret = 0;
break;
}
closedir(dir);
out:
VIR_FREE(pcidev_sysfs_net_path);
return ret;
}
int
pciDeviceGetVirtualFunctionInfo(const char *vf_sysfs_device_path,
char **pfname, int *vf_index)
{
struct pci_config_address *pf_config_address = NULL;
char *pf_sysfs_device_path = NULL;
int ret = -1;
if (pciGetPhysicalFunction(vf_sysfs_device_path, &pf_config_address) < 0)
return ret;
if (pciConfigAddressToSysfsFile(pf_config_address,
&pf_sysfs_device_path) < 0) {
VIR_FREE(pf_config_address);
return ret;
}
if (pciGetVirtualFunctionIndex(pf_sysfs_device_path, vf_sysfs_device_path,
vf_index) < 0)
goto cleanup;
ret = pciDeviceNetName(pf_sysfs_device_path, pfname);
cleanup:
VIR_FREE(pf_config_address);
VIR_FREE(pf_sysfs_device_path);
return ret;
}
#else
static const char *unsupported = N_("not supported on non-linux platforms");
int
pciGetPhysicalFunction(const char *vf_sysfs_path ATTRIBUTE_UNUSED,
struct pci_config_address **physical_function ATTRIBUTE_UNUSED)
{
virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _(unsupported));
return -1;
}
int
pciGetVirtualFunctions(const char *sysfs_path ATTRIBUTE_UNUSED,
struct pci_config_address ***virtual_functions ATTRIBUTE_UNUSED,
unsigned int *num_virtual_functions ATTRIBUTE_UNUSED)
{
virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _(unsupported));
return -1;
}
int
pciDeviceIsVirtualFunction(const char *vf_sysfs_device_link ATTRIBUTE_UNUSED)
{
virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _(unsupported));
return -1;
}
int
pciGetVirtualFunctionIndex(const char *pf_sysfs_device_link ATTRIBUTE_UNUSED,
const char *vf_sysfs_device_link ATTRIBUTE_UNUSED,
int *vf_index ATTRIBUTE_UNUSED)
{
virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _(unsupported));
return -1;
}
int
pciConfigAddressToSysfsFile(struct pci_config_address *dev ATTRIBUTE_UNUSED,
char **pci_sysfs_device_link ATTRIBUTE_UNUSED)
{
virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _(unsupported));
return -1;
}
int
pciDeviceNetName(char *device_link_sysfs_path ATTRIBUTE_UNUSED,
char **netname ATTRIBUTE_UNUSED)
{
virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _(unsupported));
return -1;
}
int
pciDeviceGetVirtualFunctionInfo(const char *vf_sysfs_device_path ATTRIBUTE_UNUSED,
char **pfname ATTRIBUTE_UNUSED,
int *vf_index ATTRIBUTE_UNUSED)
{
virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _(unsupported));
return -1;
}
#endif /* __linux__ */
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