// SPDX-License-Identifier: GPL-2.0
/*
* PCI Express I/O Virtualization (IOV) support
* Single Root IOV 1.0
* Address Translation Service 1.0
*
* Copyright (C) 2009 Intel Corporation, Yu Zhao <[email protected]>
*/
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <linux/string.h>
#include <linux/delay.h>
#include "pci.h"
#define VIRTFN_ID_LEN 17 /* "virtfn%u\0" for 2^32 - 1 */
int pci_iov_virtfn_bus(struct pci_dev *dev, int vf_id)
{
if (!dev->is_physfn)
return -EINVAL;
return dev->bus->number + ((dev->devfn + dev->sriov->offset +
dev->sriov->stride * vf_id) >> 8);
}
int pci_iov_virtfn_devfn(struct pci_dev *dev, int vf_id)
{
if (!dev->is_physfn)
return -EINVAL;
return (dev->devfn + dev->sriov->offset +
dev->sriov->stride * vf_id) & 0xff;
}
EXPORT_SYMBOL_GPL(pci_iov_virtfn_devfn);
int pci_iov_vf_id(struct pci_dev *dev)
{
struct pci_dev *pf;
if (!dev->is_virtfn)
return -EINVAL;
pf = pci_physfn(dev);
return (pci_dev_id(dev) - (pci_dev_id(pf) + pf->sriov->offset)) /
pf->sriov->stride;
}
EXPORT_SYMBOL_GPL(pci_iov_vf_id);
/**
* pci_iov_get_pf_drvdata - Return the drvdata of a PF
* @dev: VF pci_dev
* @pf_driver: Device driver required to own the PF
*
* This must be called from a context that ensures that a VF driver is attached.
* The value returned is invalid once the VF driver completes its remove()
* callback.
*
* Locking is achieved by the driver core. A VF driver cannot be probed until
* pci_enable_sriov() is called and pci_disable_sriov() does not return until
* all VF drivers have completed their remove().
*
* The PF driver must call pci_disable_sriov() before it begins to destroy the
* drvdata.
*/
void *pci_iov_get_pf_drvdata(struct pci_dev *dev, struct pci_driver *pf_driver)
{
struct pci_dev *pf_dev;
if (!dev->is_virtfn)
return ERR_PTR(-EINVAL);
pf_dev = dev->physfn;
if (pf_dev->driver != pf_driver)
return ERR_PTR(-EINVAL);
return pci_get_drvdata(pf_dev);
}
EXPORT_SYMBOL_GPL(pci_iov_get_pf_drvdata);
/*
* Per SR-IOV spec sec 3.3.10 and 3.3.11, First VF Offset and VF Stride may
* change when NumVFs changes.
*
* Update iov->offset and iov->stride when NumVFs is written.
*/
static inline void pci_iov_set_numvfs(struct pci_dev *dev, int nr_virtfn)
{
struct pci_sriov *iov = dev->sriov;
pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn);
pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &iov->offset);
pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &iov->stride);
}
/*
* The PF consumes one bus number. NumVFs, First VF Offset, and VF Stride
* determine how many additional bus numbers will be consumed by VFs.
*
* Iterate over all valid NumVFs, validate offset and stride, and calculate
* the maximum number of bus numbers that could ever be required.
*/
static int compute_max_vf_buses(struct pci_dev *dev)
{
struct pci_sriov *iov = dev->sriov;
int nr_virtfn, busnr, rc = 0;
for (nr_virtfn = iov->total_VFs; nr_virtfn; nr_virtfn--) {
pci_iov_set_numvfs(dev, nr_virtfn);
if (!iov->offset || (nr_virtfn > 1 && !iov->stride)) {
rc = -EIO;
goto out;
}
busnr = pci_iov_virtfn_bus(dev, nr_virtfn - 1);
if (busnr > iov->max_VF_buses)
iov->max_VF_buses = busnr;
}
out:
pci_iov_set_numvfs(dev, 0);
return rc;
}
static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr)
{
struct pci_bus *child;
if (bus->number == busnr)
return bus;
child = pci_find_bus(pci_domain_nr(bus), busnr);
if (child)
return child;
child = pci_add_new_bus(bus, NULL, busnr);
if (!child)
return NULL;
pci_bus_insert_busn_res(child, busnr, busnr);
return child;
}
static void virtfn_remove_bus(struct pci_bus *physbus, struct pci_bus *virtbus)
{
if (physbus != virtbus && list_empty(&virtbus->devices))
pci_remove_bus(virtbus);
}
resource_size_t pci_iov_resource_size(struct pci_dev *dev, int resno)
{
if (!dev->is_physfn)
return 0;
return dev->sriov->barsz[resno - PCI_IOV_RESOURCES];
}
static void pci_read_vf_config_common(struct pci_dev *virtfn)
{
struct pci_dev *physfn = virtfn->physfn;
/*
* Some config registers are the same across all associated VFs.
* Read them once from VF0 so we can skip reading them from the
* other VFs.
*
* PCIe r4.0, sec 9.3.4.1, technically doesn't require all VFs to
* have the same Revision ID and Subsystem ID, but we assume they
* do.
*/
pci_read_config_dword(virtfn, PCI_CLASS_REVISION,
&physfn->sriov->class);
pci_read_config_byte(virtfn, PCI_HEADER_TYPE,
&physfn->sriov->hdr_type);
pci_read_config_word(virtfn, PCI_SUBSYSTEM_VENDOR_ID,
&physfn->sriov->subsystem_vendor);
pci_read_config_word(virtfn, PCI_SUBSYSTEM_ID,
&physfn->sriov->subsystem_device);
}
int pci_iov_sysfs_link(struct pci_dev *dev,
struct pci_dev *virtfn, int id)
{
char buf[VIRTFN_ID_LEN];
int rc;
sprintf(buf, "virtfn%u", id);
rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf);
if (rc)
goto failed;
rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn");
if (rc)
goto failed1;
kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE);
return 0;
failed1:
sysfs_remove_link(&dev->dev.kobj, buf);
failed:
return rc;
}
#ifdef CONFIG_PCI_MSI
static ssize_t sriov_vf_total_msix_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct pci_dev *pdev = to_pci_dev(dev);
u32 vf_total_msix = 0;
device_lock(dev);
if (!pdev->driver || !pdev->driver->sriov_get_vf_total_msix)
goto unlock;
vf_total_msix = pdev->driver->sriov_get_vf_total_msix(pdev);
unlock:
device_unlock(dev);
return sysfs_emit(buf, "%u\n", vf_total_msix);
}
static DEVICE_ATTR_RO(sriov_vf_total_msix);
static ssize_t sriov_vf_msix_count_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct pci_dev *vf_dev = to_pci_dev(dev);
struct pci_dev *pdev = pci_physfn(vf_dev);
int val, ret = 0;
if (kstrtoint(buf, 0, &val) < 0)
return -EINVAL;
if (val < 0)
return -EINVAL;
device_lock(&pdev->dev);
if (!pdev->driver || !pdev->driver->sriov_set_msix_vec_count) {
ret = -EOPNOTSUPP;
goto err_pdev;
}
device_lock(&vf_dev->dev);
if (vf_dev->driver) {
/*
* A driver is already attached to this VF and has configured
* itself based on the current MSI-X vector count. Changing
* the vector size could mess up the driver, so block it.
*/
ret = -EBUSY;
goto err_dev;
}
ret = pdev->driver->sriov_set_msix_vec_count(vf_dev, val);
err_dev:
device_unlock(&vf_dev->dev);
err_pdev:
device_unlock(&pdev->dev);
return ret ? : count;
}
static DEVICE_ATTR_WO(sriov_vf_msix_count);
#endif
static struct attribute *sriov_vf_dev_attrs[] = {
#ifdef CONFIG_PCI_MSI
&dev_attr_sriov_vf_msix_count.attr,
#endif
NULL,
};
static umode_t sriov_vf_attrs_are_visible(struct kobject *kobj,
struct attribute *a, int n)
{
struct device *dev = kobj_to_dev(kobj);
struct pci_dev *pdev = to_pci_dev(dev);
if (!pdev->is_virtfn)
return 0;
return a->mode;
}
const struct attribute_group sriov_vf_dev_attr_group = {
.attrs = sriov_vf_dev_attrs,
.is_visible = sriov_vf_attrs_are_visible,
};
int pci_iov_add_virtfn(struct pci_dev *dev, int id)
{
int i;
int rc = -ENOMEM;
u64 size;
struct pci_dev *virtfn;
struct resource *res;
struct pci_sriov *iov = dev->sriov;
struct pci_bus *bus;
bus = virtfn_add_bus(dev->bus, pci_iov_virtfn_bus(dev, id));
if (!bus)
goto failed;
virtfn = pci_alloc_dev(bus);
if (!virtfn)
goto failed0;
virtfn->devfn = pci_iov_virtfn_devfn(dev, id);
virtfn->vendor = dev->vendor;
virtfn->device = iov->vf_device;
virtfn->is_virtfn = 1;
virtfn->physfn = pci_dev_get(dev);
virtfn->no_command_memory = 1;
if (id == 0)
pci_read_vf_config_common(virtfn);
rc = pci_setup_device(virtfn);
if (rc)
goto failed1;
virtfn->dev.parent = dev->dev.parent;
virtfn->multifunction = 0;
for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
res = &dev->resource[i + PCI_IOV_RESOURCES];
if (!res->parent)
continue;
virtfn->resource[i].name = pci_name(virtfn);
virtfn->resource[i].flags = res->flags;
size = pci_iov_resource_size(dev, i + PCI_IOV_RESOURCES);
virtfn->resource[i].start = res->start + size * id;
virtfn->resource[i].end = virtfn->resource[i].start + size - 1;
rc = request_resource(res, &virtfn->resource[i]);
BUG_ON(rc);
}
pci_device_add(virtfn, virtfn->bus);
rc = pci_iov_sysfs_link(dev, virtfn, id);
if (rc)
goto failed1;
pci_bus_add_device(virtfn);
return 0;
failed1:
pci_stop_and_remove_bus_device(virtfn);
pci_dev_put(dev);
failed0:
virtfn_remove_bus(dev->bus, bus);
failed:
return rc;
}
void pci_iov_remove_virtfn(struct pci_dev *dev, int id)
{
char buf[VIRTFN_ID_LEN];
struct pci_dev *virtfn;
virtfn = pci_get_domain_bus_and_slot(pci_domain_nr(dev->bus),
pci_iov_virtfn_bus(dev, id),
pci_iov_virtfn_devfn(dev, id));
if (!virtfn)
return;
sprintf(buf, "virtfn%u", id);
sysfs_remove_link(&dev->dev.kobj, buf);
/*
* pci_stop_dev() could have been called for this virtfn already,
* so the directory for the virtfn may have been removed before.
* Double check to avoid spurious sysfs warnings.
*/
if (virtfn->dev.kobj.sd)
sysfs_remove_link(&virtfn->dev.kobj, "physfn");
pci_stop_and_remove_bus_device(virtfn);
virtfn_remove_bus(dev->bus, virtfn->bus);
/* balance pci_get_domain_bus_and_slot() */
pci_dev_put(virtfn);
pci_dev_put(dev);
}
static ssize_t sriov_totalvfs_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct pci_dev *pdev = to_pci_dev(dev);
return sysfs_emit(buf, "%u\n", pci_sriov_get_totalvfs(pdev));
}
static ssize_t sriov_numvfs_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct pci_dev *pdev = to_pci_dev(dev);
u16 num_vfs;
/* Serialize vs sriov_numvfs_store() so readers see valid num_VFs */
device_lock(&pdev->dev);
num_vfs = pdev->sriov->num_VFs;
device_unlock(&pdev->dev);
return sysfs_emit(buf, "%u\n", num_vfs);
}
/*
* num_vfs > 0; number of VFs to enable
* num_vfs = 0; disable all VFs
*
* Note: SRIOV spec does not allow partial VF
* disable, so it's all or none.
*/
static ssize_t sriov_numvfs_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct pci_dev *pdev = to_pci_dev(dev);
int ret = 0;
u16 num_vfs;
if (kstrtou16(buf, 0, &num_vfs) < 0)
return -EINVAL;
if (num_vfs > pci_sriov_get_totalvfs(pdev))
return -ERANGE;
device_lock(&pdev->dev);
if (num_vfs == pdev->sriov->num_VFs)
goto exit;
/* is PF driver loaded */
if (!pdev->driver) {
pci_info(pdev, "no driver bound to device; cannot configure SR-IOV\n");
ret = -ENOENT;
goto exit;
}
/* is PF driver loaded w/callback */
if (!pdev->driver->sriov_configure) {
pci_info(pdev, "driver does not support SR-IOV configuration via sysfs\n");
ret = -ENOENT;
goto exit;
}
if (num_vfs == 0) {
/* disable VFs */
ret = pdev->driver->sriov_configure(pdev, 0);
goto exit;
}
/* enable VFs */
if (pdev->sriov->num_VFs) {
pci_warn(pdev, "%d VFs already enabled. Disable before enabling %d VFs\n",
pdev->sriov->num_VFs, num_vfs);
ret = -EBUSY;
goto exit;
}
ret = pdev->driver->sriov_configure(pdev, num_vfs);
if (ret < 0)
goto exit;
if (ret != num_vfs)
pci_warn(pdev, "%d VFs requested; only %d enabled\n",
num_vfs, ret);
exit:
device_unlock(&pdev->dev);
if (ret < 0)
return ret;
return count;
}
static ssize_t sriov_offset_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct pci_dev *pdev = to_pci_dev(dev);
return sysfs_emit(buf, "%u\n", pdev->sriov->offset);
}
static ssize_t sriov_stride_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct pci_dev *pdev = to_pci_dev(dev);
return sysfs_emit(buf, "%u\n", pdev->sriov->stride);
}
static ssize_t sriov_vf_device_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct pci_dev *pdev = to_pci_dev(dev);
return sysfs_emit(buf, "%x\n", pdev->sriov->vf_device);
}
static ssize_t sriov_drivers_autoprobe_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct pci_dev *pdev = to_pci_dev(dev);
return sysfs_emit(buf, "%u\n", pdev->sriov->drivers_autoprobe);
}
static ssize_t sriov_drivers_autoprobe_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct pci_dev *pdev = to_pci_dev(dev);
bool drivers_autoprobe;
if (kstrtobool(buf, &drivers_autoprobe) < 0)
return -EINVAL;
pdev->sriov->drivers_autoprobe = drivers_autoprobe;
return count;
}
static DEVICE_ATTR_RO(sriov_totalvfs);
static DEVICE_ATTR_RW(sriov_numvfs);
static DEVICE_ATTR_RO(sriov_offset);
static DEVICE_ATTR_RO(sriov_stride);
static DEVICE_ATTR_RO(sriov_vf_device);
static DEVICE_ATTR_RW(sriov_drivers_autoprobe);
static struct attribute *sriov_pf_dev_attrs[] = {
&dev_attr_sriov_totalvfs.attr,
&dev_attr_sriov_numvfs.attr,
&dev_attr_sriov_offset.attr,
&dev_attr_sriov_stride.attr,
&dev_attr_sriov_vf_device.attr,
&dev_attr_sriov_drivers_autoprobe.attr,
#ifdef CONFIG_PCI_MSI
&dev_attr_sriov_vf_total_msix.attr,
#endif
NULL,
};
static umode_t sriov_pf_attrs_are_visible(struct kobject *kobj,
struct attribute *a, int n)
{
struct device *dev = kobj_to_dev(kobj);
if (!dev_is_pf(dev))
return 0;
return a->mode;
}
const struct attribute_group sriov_pf_dev_attr_group = {
.attrs = sriov_pf_dev_attrs,
.is_visible = sriov_pf_attrs_are_visible,
};
int __weak pcibios_sriov_enable(struct pci_dev *pdev, u16 num_vfs)
{
return 0;
}
int __weak pcibios_sriov_disable(struct pci_dev *pdev)
{
return 0;
}
static int sriov_add_vfs(struct pci_dev *dev, u16 num_vfs)
{
unsigned int i;
int rc;
if (dev->no_vf_scan)
return 0;
for (i = 0; i < num_vfs; i++) {
rc = pci_iov_add_virtfn(dev, i);
if (rc)
goto failed;
}
return 0;
failed:
while (i--)
pci_iov_remove_virtfn(dev, i);
return rc;
}
static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
{
int rc;
int i;
int nres;
u16 initial;
struct resource *res;
struct pci_dev *pdev;
struct pci_sriov *iov = dev->sriov;
int bars = 0;
int bus;
if (!nr_virtfn)
return 0;
if (iov->num_VFs)
return -EINVAL;
pci_read_config_word(dev, iov->pos + PCI_SRIOV_INITIAL_VF, &initial);
if (initial > iov->total_VFs ||
(!(iov->cap & PCI_SRIOV_CAP_VFM) && (initial != iov->total_VFs)))
return -EIO;
if (nr_virtfn < 0 || nr_virtfn > iov->total_VFs ||
(!(iov->cap & PCI_SRIOV_CAP_VFM) && (nr_virtfn > initial)))
return -EINVAL;
nres = 0;
for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
bars |= (1 << (i + PCI_IOV_RESOURCES));
res = &dev->resource[i + PCI_IOV_RESOURCES];
if (res->parent)
nres++;
}
if (nres != iov->nres) {
pci_err(dev, "not enough MMIO resources for SR-IOV\n");
return -ENOMEM;
}
bus = pci_iov_virtfn_bus(dev, nr_virtfn - 1);
if (bus > dev->bus->busn_res.end) {
pci_err(dev, "can't enable %d VFs (bus %02x out of range of %pR)\n",
nr_virtfn, bus, &dev->bus->busn_res);
return -ENOMEM;
}
if (pci_enable_resources(dev, bars)) {
pci_err(dev, "SR-IOV: IOV BARS not allocated\n");
return -ENOMEM;
}
if (iov->link != dev->devfn) {
pdev = pci_get_slot(dev->bus, iov->link);
if (!pdev)
return -ENODEV;
if (!pdev->is_physfn) {
pci_dev_put(pdev);
return -ENOSYS;
}
rc = sysfs_create_link(&dev->dev.kobj,
&pdev->dev.kobj, "dep_link");
pci_dev_put(pdev);
if (rc)
return rc;
}
iov->initial_VFs = initial;
if (nr_virtfn < initial)
initial = nr_virtfn;
rc = pcibios_sriov_enable(dev, initial);
if (rc) {
pci_err(dev, "failure %d from pcibios_sriov_enable()\n", rc);
goto err_pcibios;
}
pci_iov_set_numvfs(dev, nr_virtfn);
iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE;
pci_cfg_access_lock(dev);
pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
msleep(100);
pci_cfg_access_unlock(dev);
rc = sriov_add_vfs(dev, initial);
if (rc)
goto err_pcibios;
kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE);
iov->num_VFs = nr_virtfn;
return 0;
err_pcibios:
iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
pci_cfg_access_lock(dev);
pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
ssleep(1);
pci_cfg_access_unlock(dev);
pcibios_sriov_disable(dev);
if (iov->link != dev->devfn)
sysfs_remove_link(&dev->dev.kobj, "dep_link");
pci_iov_set_numvfs(dev, 0);
return rc;
}
static void sriov_del_vfs(struct pci_dev *dev)
{
struct pci_sriov *iov = dev->sriov;
int i;
for (i = 0; i < iov->num_VFs; i++)
pci_iov_remove_virtfn(dev, i);
}
static void sriov_disable(struct pci_dev *dev)
{
struct pci_sriov *iov = dev->sriov;
if (!iov->num_VFs)
return;
sriov_del_vfs(dev);
iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
pci_cfg_access_lock(dev);
pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
ssleep(1);
pci_cfg_access_unlock(dev);
pcibios_sriov_disable(dev);
if (iov->link != dev->devfn)
sysfs_remove_link(&dev->dev.kobj, "dep_link");
iov->num_VFs = 0;
pci_iov_set_numvfs(dev, 0);
}
static int sriov_init(struct pci_dev *dev, int pos)
{
int i, bar64;
int rc;
int nres;
u32 pgsz;
u16 ctrl, total;
struct pci_sriov *iov;
struct resource *res;
const char *res_name;
struct pci_dev *pdev;
pci_read_config_word(dev, pos + PCI_SRIOV_CTRL, &ctrl);
if (ctrl & PCI_SRIOV_CTRL_VFE) {
pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, 0);
ssleep(1);
}
ctrl = 0;
list_for_each_entry(pdev, &dev->bus->devices, bus_list)
if (pdev->is_physfn)
goto found;
pdev = NULL;
if (pci_ari_enabled(dev->bus))
ctrl |= PCI_SRIOV_CTRL_ARI;
found:
pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, ctrl);
pci_read_config_word(dev, pos + PCI_SRIOV_TOTAL_VF, &total);
if (!total)
return 0;
pci_read_config_dword(dev, pos + PCI_SRIOV_SUP_PGSIZE, &pgsz);
i = PAGE_SHIFT > 12 ? PAGE_SHIFT - 12 : 0;
pgsz &= ~((1 << i) - 1);
if (!pgsz)
return -EIO;
pgsz &= ~(pgsz - 1);
pci_write_config_dword(dev, pos + PCI_SRIOV_SYS_PGSIZE, pgsz);
iov = kzalloc(sizeof(*iov), GFP_KERNEL);
if (!iov)
return -ENOMEM;
nres = 0;
for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
res = &dev->resource[i + PCI_IOV_RESOURCES];
res_name = pci_resource_name(dev, i + PCI_IOV_RESOURCES);
/*
* If it is already FIXED, don't change it, something
* (perhaps EA or header fixups) wants it this way.
*/
if (res->flags & IORESOURCE_PCI_FIXED)
bar64 = (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
else
bar64 = __pci_read_base(dev, pci_bar_unknown, res,
pos + PCI_SRIOV_BAR + i * 4);
if (!res->flags)
continue;
if (resource_size(res) & (PAGE_SIZE - 1)) {
rc = -EIO;
goto failed;
}
iov->barsz[i] = resource_size(res);
res->end = res->start + resource_size(res) * total - 1;
pci_info(dev, "%s %pR: contains BAR %d for %d VFs\n",
res_name, res, i, total);
i += bar64;
nres++;
}
iov->pos = pos;
iov->nres = nres;
iov->ctrl = ctrl;
iov->total_VFs = total;
iov->driver_max_VFs = total;
pci_read_config_word(dev, pos + PCI_SRIOV_VF_DID, &iov->vf_device);
iov->pgsz = pgsz;
iov->self = dev;
iov->drivers_autoprobe = true;
pci_read_config_dword(dev, pos + PCI_SRIOV_CAP, &iov->cap);
pci_read_config_byte(dev, pos + PCI_SRIOV_FUNC_LINK, &iov->link);
if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END)
iov->link = PCI_DEVFN(PCI_SLOT(dev->devfn), iov->link);
if (pdev)
iov->dev = pci_dev_get(pdev);
else
iov->dev = dev;
dev->sriov = iov;
dev->is_physfn = 1;
rc = compute_max_vf_buses(dev);
if (rc)
goto fail_max_buses;
return 0;
fail_max_buses:
dev->sriov = NULL;
dev->is_physfn = 0;
failed:
for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
res = &dev->resource[i + PCI_IOV_RESOURCES];
res->flags = 0;
}
kfree(iov);
return rc;
}
static void sriov_release(struct pci_dev *dev)
{
BUG_ON(dev->sriov->num_VFs);
if (dev != dev->sriov->dev)
pci_dev_put(dev->sriov->dev);
kfree(dev->sriov);
dev->sriov = NULL;
}
static void sriov_restore_state(struct pci_dev *dev)
{
int i;
u16 ctrl;
struct pci_sriov *iov = dev->sriov;
pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &ctrl);
if (ctrl & PCI_SRIOV_CTRL_VFE)
return;
/*
* Restore PCI_SRIOV_CTRL_ARI before pci_iov_set_numvfs() because
* it reads offset & stride, which depend on PCI_SRIOV_CTRL_ARI.
*/
ctrl &= ~PCI_SRIOV_CTRL_ARI;
ctrl |= iov->ctrl & PCI_SRIOV_CTRL_ARI;
pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, ctrl);
for (i = 0; i < PCI_SRIOV_NUM_BARS; i++)
pci_update_resource(dev, i + PCI_IOV_RESOURCES);
pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz);
pci_iov_set_numvfs(dev, iov->num_VFs);
pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
if (iov->ctrl & PCI_SRIOV_CTRL_VFE)
msleep(100);
}
/**
* pci_iov_init - initialize the IOV capability
* @dev: the PCI device
*
* Returns 0 on success, or negative on failure.
*/
int pci_iov_init(struct pci_dev *dev)
{
int pos;
if (!pci_is_pcie(dev))
return -ENODEV;
pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV);
if (pos)
return sriov_init(dev, pos);
return -ENODEV;
}
/**
* pci_iov_release - release resources used by the IOV capability
* @dev: the PCI device
*/
void pci_iov_release(struct pci_dev *dev)
{
if (dev->is_physfn)
sriov_release(dev);
}
/**
* pci_iov_remove - clean up SR-IOV state after PF driver is detached
* @dev: the PCI device
*/
void pci_iov_remove(struct pci_dev *dev)
{
struct pci_sriov *iov = dev->sriov;
if (!dev->is_physfn)
return;
iov->driver_max_VFs = iov->total_VFs;
if (iov->num_VFs)
pci_warn(dev, "driver left SR-IOV enabled after remove\n");
}
/**
* pci_iov_update_resource - update a VF BAR
* @dev: the PCI device
* @resno: the resource number
*
* Update a VF BAR in the SR-IOV capability of a PF.
*/
void pci_iov_update_resource(struct pci_dev *dev, int resno)
{
struct pci_sriov *iov = dev->is_physfn ? dev->sriov : NULL;
struct resource *res = dev->resource + resno;
int vf_bar = resno - PCI_IOV_RESOURCES;
struct pci_bus_region region;
u16 cmd;
u32 new;
int reg;
/*
* The generic pci_restore_bars() path calls this for all devices,
* including VFs and non-SR-IOV devices. If this is not a PF, we
* have nothing to do.
*/
if (!iov)
return;
pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &cmd);
if ((cmd & PCI_SRIOV_CTRL_VFE) && (cmd & PCI_SRIOV_CTRL_MSE)) {
dev_WARN(&dev->dev, "can't update enabled VF BAR%d %pR\n",
vf_bar, res);
return;
}
/*
* Ignore unimplemented BARs, unused resource slots for 64-bit
* BARs, and non-movable resources, e.g., those described via
* Enhanced Allocation.
*/
if (!res->flags)
return;
if (res->flags & IORESOURCE_UNSET)
return;
if (res->flags & IORESOURCE_PCI_FIXED)
return;
pcibios_resource_to_bus(dev->bus, ®ion, res);
new = region.start;
new |= res->flags & ~PCI_BASE_ADDRESS_MEM_MASK;
reg = iov->pos + PCI_SRIOV_BAR + 4 * vf_bar;
pci_write_config_dword(dev, reg, new);
if (res->flags & IORESOURCE_MEM_64) {
new = region.start >> 16 >> 16;
pci_write_config_dword(dev, reg + 4, new);
}
}
resource_size_t __weak pcibios_iov_resource_alignment(struct pci_dev *dev,
int resno)
{
return pci_iov_resource_size(dev, resno);
}
/**
* pci_sriov_resource_alignment - get resource alignment for VF BAR
* @dev: the PCI device
* @resno: the resource number
*
* Returns the alignment of the VF BAR found in the SR-IOV capability.
* This is not the same as the resource size which is defined as
* the VF BAR size multiplied by the number of VFs. The alignment
* is just the VF BAR size.
*/
resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno)
{
return pcibios_iov_resource_alignment(dev, resno);
}
/**
* pci_restore_iov_state - restore the state of the IOV capability
* @dev: the PCI device
*/
void pci_restore_iov_state(struct pci_dev *dev)
{
if (dev->is_physfn)
sriov_restore_state(dev);
}
/**
* pci_vf_drivers_autoprobe - set PF property drivers_autoprobe for VFs
* @dev: the PCI device
* @auto_probe: set VF drivers auto probe flag
*/
void pci_vf_drivers_autoprobe(struct pci_dev *dev, bool auto_probe)
{
if (dev->is_physfn)
dev->sriov->drivers_autoprobe = auto_probe;
}
/**
* pci_iov_bus_range - find bus range used by Virtual Function
* @bus: the PCI bus
*
* Returns max number of buses (exclude current one) used by Virtual
* Functions.
*/
int pci_iov_bus_range(struct pci_bus *bus)
{
int max = 0;
struct pci_dev *dev;
list_for_each_entry(dev, &bus->devices, bus_list) {
if (!dev->is_physfn)
continue;
if (dev->sriov->max_VF_buses > max)
max = dev->sriov->max_VF_buses;
}
return max ? max - bus->number : 0;
}
/**
* pci_enable_sriov - enable the SR-IOV capability
* @dev: the PCI device
* @nr_virtfn: number of virtual functions to enable
*
* Returns 0 on success, or negative on failure.
*/
int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn)
{
might_sleep();
if (!dev->is_physfn)
return -ENOSYS;
return sriov_enable(dev, nr_virtfn);
}
EXPORT_SYMBOL_GPL(pci_enable_sriov);
/**
* pci_disable_sriov - disable the SR-IOV capability
* @dev: the PCI device
*/
void pci_disable_sriov(struct pci_dev *dev)
{
might_sleep();
if (!dev->is_physfn)
return;
sriov_disable(dev);
}
EXPORT_SYMBOL_GPL(pci_disable_sriov);
/**
* pci_num_vf - return number of VFs associated with a PF device_release_driver
* @dev: the PCI device
*
* Returns number of VFs, or 0 if SR-IOV is not enabled.
*/
int pci_num_vf(struct pci_dev *dev)
{
if (!dev->is_physfn)
return 0;
return dev->sriov->num_VFs;
}
EXPORT_SYMBOL_GPL(pci_num_vf);
/**
* pci_vfs_assigned - returns number of VFs are assigned to a guest
* @dev: the PCI device
*
* Returns number of VFs belonging to this device that are assigned to a guest.
* If device is not a physical function returns 0.
*/
int pci_vfs_assigned(struct pci_dev *dev)
{
struct pci_dev *vfdev;
unsigned int vfs_assigned = 0;
unsigned short dev_id;
/* only search if we are a PF */
if (!dev->is_physfn)
return 0;
/*
* determine the device ID for the VFs, the vendor ID will be the
* same as the PF so there is no need to check for that one
*/
dev_id = dev->sriov->vf_device;
/* loop through all the VFs to see if we own any that are assigned */
vfdev = pci_get_device(dev->vendor, dev_id, NULL);
while (vfdev) {
/*
* It is considered assigned if it is a virtual function with
* our dev as the physical function and the assigned bit is set
*/
if (vfdev->is_virtfn && (vfdev->physfn == dev) &&
pci_is_dev_assigned(vfdev))
vfs_assigned++;
vfdev = pci_get_device(dev->vendor, dev_id, vfdev);
}
return vfs_assigned;
}
EXPORT_SYMBOL_GPL(pci_vfs_assigned);
/**
* pci_sriov_set_totalvfs -- reduce the TotalVFs available
* @dev: the PCI PF device
* @numvfs: number that should be used for TotalVFs supported
*
* Should be called from PF driver's probe routine with
* device's mutex held.
*
* Returns 0 if PF is an SRIOV-capable device and
* value of numvfs valid. If not a PF return -ENOSYS;
* if numvfs is invalid return -EINVAL;
* if VFs already enabled, return -EBUSY.
*/
int pci_sriov_set_totalvfs(struct pci_dev *dev, u16 numvfs)
{
if (!dev->is_physfn)
return -ENOSYS;
if (numvfs > dev->sriov->total_VFs)
return -EINVAL;
/* Shouldn't change if VFs already enabled */
if (dev->sriov->ctrl & PCI_SRIOV_CTRL_VFE)
return -EBUSY;
dev->sriov->driver_max_VFs = numvfs;
return 0;
}
EXPORT_SYMBOL_GPL(pci_sriov_set_totalvfs);
/**
* pci_sriov_get_totalvfs -- get total VFs supported on this device
* @dev: the PCI PF device
*
* For a PCIe device with SRIOV support, return the PCIe
* SRIOV capability value of TotalVFs or the value of driver_max_VFs
* if the driver reduced it. Otherwise 0.
*/
int pci_sriov_get_totalvfs(struct pci_dev *dev)
{
if (!dev->is_physfn)
return 0;
return dev->sriov->driver_max_VFs;
}
EXPORT_SYMBOL_GPL(pci_sriov_get_totalvfs);
/**
* pci_sriov_configure_simple - helper to configure SR-IOV
* @dev: the PCI device
* @nr_virtfn: number of virtual functions to enable, 0 to disable
*
* Enable or disable SR-IOV for devices that don't require any PF setup
* before enabling SR-IOV. Return value is negative on error, or number of
* VFs allocated on success.
*/
int pci_sriov_configure_simple(struct pci_dev *dev, int nr_virtfn)
{
int rc;
might_sleep();
if (!dev->is_physfn)
return -ENODEV;
if (pci_vfs_assigned(dev)) {
pci_warn(dev, "Cannot modify SR-IOV while VFs are assigned\n");
return -EPERM;
}
if (nr_virtfn == 0) {
sriov_disable(dev);
return 0;
}
rc = sriov_enable(dev, nr_virtfn);
if (rc < 0)
return rc;
return nr_virtfn;
}
EXPORT_SYMBOL_GPL(pci_sriov_configure_simple);
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