PCI: add SR-IOV API for Physical Function driver

Add or remove the Virtual Function when the SR-IOV is enabled or
disabled by the device driver. This can happen anytime rather than
only at the device probe stage.

Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This commit is contained in:
Yu Zhao 2009-03-20 11:25:15 +08:00 committed by Jesse Barnes
parent 480b93b783
commit dd7cc44d0b
3 changed files with 334 additions and 1 deletions

View File

@ -13,6 +13,7 @@
#include <linux/delay.h>
#include "pci.h"
#define VIRTFN_ID_LEN 16
static inline u8 virtfn_bus(struct pci_dev *dev, int id)
{
@ -26,6 +27,284 @@ static inline u8 virtfn_devfn(struct pci_dev *dev, int id)
dev->sriov->stride * id) & 0xff;
}
static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr)
{
int rc;
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;
child->subordinate = busnr;
child->dev.parent = bus->bridge;
rc = pci_bus_add_child(child);
if (rc) {
pci_remove_bus(child);
return NULL;
}
return child;
}
static void virtfn_remove_bus(struct pci_bus *bus, int busnr)
{
struct pci_bus *child;
if (bus->number == busnr)
return;
child = pci_find_bus(pci_domain_nr(bus), busnr);
BUG_ON(!child);
if (list_empty(&child->devices))
pci_remove_bus(child);
}
static int virtfn_add(struct pci_dev *dev, int id, int reset)
{
int i;
int rc;
u64 size;
char buf[VIRTFN_ID_LEN];
struct pci_dev *virtfn;
struct resource *res;
struct pci_sriov *iov = dev->sriov;
virtfn = alloc_pci_dev();
if (!virtfn)
return -ENOMEM;
mutex_lock(&iov->dev->sriov->lock);
virtfn->bus = virtfn_add_bus(dev->bus, virtfn_bus(dev, id));
if (!virtfn->bus) {
kfree(virtfn);
mutex_unlock(&iov->dev->sriov->lock);
return -ENOMEM;
}
virtfn->devfn = virtfn_devfn(dev, id);
virtfn->vendor = dev->vendor;
pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_DID, &virtfn->device);
pci_setup_device(virtfn);
virtfn->dev.parent = dev->dev.parent;
for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
res = dev->resource + PCI_IOV_RESOURCES + i;
if (!res->parent)
continue;
virtfn->resource[i].name = pci_name(virtfn);
virtfn->resource[i].flags = res->flags;
size = resource_size(res);
do_div(size, iov->total);
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);
}
if (reset)
pci_execute_reset_function(virtfn);
pci_device_add(virtfn, virtfn->bus);
mutex_unlock(&iov->dev->sriov->lock);
virtfn->physfn = pci_dev_get(dev);
virtfn->is_virtfn = 1;
rc = pci_bus_add_device(virtfn);
if (rc)
goto failed1;
sprintf(buf, "virtfn%u", id);
rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf);
if (rc)
goto failed1;
rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn");
if (rc)
goto failed2;
kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE);
return 0;
failed2:
sysfs_remove_link(&dev->dev.kobj, buf);
failed1:
pci_dev_put(dev);
mutex_lock(&iov->dev->sriov->lock);
pci_remove_bus_device(virtfn);
virtfn_remove_bus(dev->bus, virtfn_bus(dev, id));
mutex_unlock(&iov->dev->sriov->lock);
return rc;
}
static void virtfn_remove(struct pci_dev *dev, int id, int reset)
{
char buf[VIRTFN_ID_LEN];
struct pci_bus *bus;
struct pci_dev *virtfn;
struct pci_sriov *iov = dev->sriov;
bus = pci_find_bus(pci_domain_nr(dev->bus), virtfn_bus(dev, id));
if (!bus)
return;
virtfn = pci_get_slot(bus, virtfn_devfn(dev, id));
if (!virtfn)
return;
pci_dev_put(virtfn);
if (reset) {
device_release_driver(&virtfn->dev);
pci_execute_reset_function(virtfn);
}
sprintf(buf, "virtfn%u", id);
sysfs_remove_link(&dev->dev.kobj, buf);
sysfs_remove_link(&virtfn->dev.kobj, "physfn");
mutex_lock(&iov->dev->sriov->lock);
pci_remove_bus_device(virtfn);
virtfn_remove_bus(dev->bus, virtfn_bus(dev, id));
mutex_unlock(&iov->dev->sriov->lock);
pci_dev_put(dev);
}
static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
{
int rc;
int i, j;
int nres;
u16 offset, stride, initial;
struct resource *res;
struct pci_dev *pdev;
struct pci_sriov *iov = dev->sriov;
if (!nr_virtfn)
return 0;
if (iov->nr_virtfn)
return -EINVAL;
pci_read_config_word(dev, iov->pos + PCI_SRIOV_INITIAL_VF, &initial);
if (initial > iov->total ||
(!(iov->cap & PCI_SRIOV_CAP_VFM) && (initial != iov->total)))
return -EIO;
if (nr_virtfn < 0 || nr_virtfn > iov->total ||
(!(iov->cap & PCI_SRIOV_CAP_VFM) && (nr_virtfn > initial)))
return -EINVAL;
pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn);
pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &offset);
pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &stride);
if (!offset || (nr_virtfn > 1 && !stride))
return -EIO;
nres = 0;
for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
res = dev->resource + PCI_IOV_RESOURCES + i;
if (res->parent)
nres++;
}
if (nres != iov->nres) {
dev_err(&dev->dev, "not enough MMIO resources for SR-IOV\n");
return -ENOMEM;
}
iov->offset = offset;
iov->stride = stride;
if (virtfn_bus(dev, nr_virtfn - 1) > dev->bus->subordinate) {
dev_err(&dev->dev, "SR-IOV: bus number out of range\n");
return -ENOMEM;
}
if (iov->link != dev->devfn) {
pdev = pci_get_slot(dev->bus, iov->link);
if (!pdev)
return -ENODEV;
pci_dev_put(pdev);
if (!pdev->is_physfn)
return -ENODEV;
rc = sysfs_create_link(&dev->dev.kobj,
&pdev->dev.kobj, "dep_link");
if (rc)
return rc;
}
iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE;
pci_block_user_cfg_access(dev);
pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
msleep(100);
pci_unblock_user_cfg_access(dev);
iov->initial = initial;
if (nr_virtfn < initial)
initial = nr_virtfn;
for (i = 0; i < initial; i++) {
rc = virtfn_add(dev, i, 0);
if (rc)
goto failed;
}
kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE);
iov->nr_virtfn = nr_virtfn;
return 0;
failed:
for (j = 0; j < i; j++)
virtfn_remove(dev, j, 0);
iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
pci_block_user_cfg_access(dev);
pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
ssleep(1);
pci_unblock_user_cfg_access(dev);
if (iov->link != dev->devfn)
sysfs_remove_link(&dev->dev.kobj, "dep_link");
return rc;
}
static void sriov_disable(struct pci_dev *dev)
{
int i;
struct pci_sriov *iov = dev->sriov;
if (!iov->nr_virtfn)
return;
for (i = 0; i < iov->nr_virtfn; i++)
virtfn_remove(dev, i, 0);
iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
pci_block_user_cfg_access(dev);
pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
ssleep(1);
pci_unblock_user_cfg_access(dev);
if (iov->link != dev->devfn)
sysfs_remove_link(&dev->dev.kobj, "dep_link");
iov->nr_virtfn = 0;
}
static int sriov_init(struct pci_dev *dev, int pos)
{
int i;
@ -132,6 +411,8 @@ static int sriov_init(struct pci_dev *dev, int pos)
static void sriov_release(struct pci_dev *dev)
{
BUG_ON(dev->sriov->nr_virtfn);
if (dev == dev->sriov->dev)
mutex_destroy(&dev->sriov->lock);
else
@ -155,6 +436,7 @@ static void sriov_restore_state(struct pci_dev *dev)
pci_update_resource(dev, i);
pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz);
pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, iov->nr_virtfn);
pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
if (iov->ctrl & PCI_SRIOV_CTRL_VFE)
msleep(100);
@ -245,3 +527,35 @@ int pci_iov_bus_range(struct pci_bus *bus)
return max ? max - bus->number : 0;
}
/**
* pci_enable_sriov - enable the SR-IOV capability
* @dev: the PCI device
*
* 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 -ENODEV;
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);

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@ -209,6 +209,8 @@ struct pci_sriov {
u32 cap; /* SR-IOV Capabilities */
u16 ctrl; /* SR-IOV Control */
u16 total; /* total VFs associated with the PF */
u16 initial; /* initial VFs associated with the PF */
u16 nr_virtfn; /* number of VFs available */
u16 offset; /* first VF Routing ID offset */
u16 stride; /* following VF stride */
u32 pgsz; /* page size for BAR alignment */

View File

@ -265,6 +265,7 @@ struct pci_dev {
unsigned int is_pcie:1;
unsigned int state_saved:1;
unsigned int is_physfn:1;
unsigned int is_virtfn:1;
pci_dev_flags_t dev_flags;
atomic_t enable_cnt; /* pci_enable_device has been called */
@ -279,7 +280,10 @@ struct pci_dev {
#endif
struct pci_vpd *vpd;
#ifdef CONFIG_PCI_IOV
union {
struct pci_sriov *sriov; /* SR-IOV capability related */
struct pci_dev *physfn; /* the PF this VF is associated with */
};
#endif
};
@ -1212,5 +1216,18 @@ int pci_ext_cfg_avail(struct pci_dev *dev);
void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar);
#ifdef CONFIG_PCI_IOV
extern int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn);
extern void pci_disable_sriov(struct pci_dev *dev);
#else
static inline int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn)
{
return -ENODEV;
}
static inline void pci_disable_sriov(struct pci_dev *dev)
{
}
#endif
#endif /* __KERNEL__ */
#endif /* LINUX_PCI_H */