464 lines
12 KiB
C
464 lines
12 KiB
C
|
/*
|
||
|
|
* PCI Backend Operations - respond to PCI requests from Frontend
|
||
|
|
*
|
||
|
|
* Author: Ryan Wilson <hap9@epoch.ncsc.mil>
|
||
|
|
*/
|
||
|
|
|
||
|
|
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
|
||
|
|
|
||
|
|
#include <linux/moduleparam.h>
|
||
|
|
#include <linux/wait.h>
|
||
|
|
#include <linux/bitops.h>
|
||
|
|
#include <xen/events.h>
|
||
|
|
#include <linux/sched.h>
|
||
|
|
#include "pciback.h"
|
||
|
|
|
||
|
|
int verbose_request;
|
||
|
|
module_param(verbose_request, int, 0644);
|
||
|
|
|
||
|
|
static irqreturn_t xen_pcibk_guest_interrupt(int irq, void *dev_id);
|
||
|
|
|
||
|
|
/* Ensure a device is has the fake IRQ handler "turned on/off" and is
|
||
|
|
* ready to be exported. This MUST be run after xen_pcibk_reset_device
|
||
|
|
* which does the actual PCI device enable/disable.
|
||
|
|
*/
|
||
|
|
static void xen_pcibk_control_isr(struct pci_dev *dev, int reset)
|
||
|
|
{
|
||
|
|
struct xen_pcibk_dev_data *dev_data;
|
||
|
|
int rc;
|
||
|
|
int enable = 0;
|
||
|
|
|
||
|
|
dev_data = pci_get_drvdata(dev);
|
||
|
|
if (!dev_data)
|
||
|
|
return;
|
||
|
|
|
||
|
|
/* We don't deal with bridges */
|
||
|
|
if (dev->hdr_type != PCI_HEADER_TYPE_NORMAL)
|
||
|
|
return;
|
||
|
|
|
||
|
|
if (reset) {
|
||
|
|
dev_data->enable_intx = 0;
|
||
|
|
dev_data->ack_intr = 0;
|
||
|
|
}
|
||
|
|
enable = dev_data->enable_intx;
|
||
|
|
|
||
|
|
/* Asked to disable, but ISR isn't runnig */
|
||
|
|
if (!enable && !dev_data->isr_on)
|
||
|
|
return;
|
||
|
|
|
||
|
|
/* Squirrel away the IRQs in the dev_data. We need this
|
||
|
|
* b/c when device transitions to MSI, the dev->irq is
|
||
|
|
* overwritten with the MSI vector.
|
||
|
|
*/
|
||
|
|
if (enable)
|
||
|
|
dev_data->irq = dev->irq;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* SR-IOV devices in all use MSI-X and have no legacy
|
||
|
|
* interrupts, so inhibit creating a fake IRQ handler for them.
|
||
|
|
*/
|
||
|
|
if (dev_data->irq == 0)
|
||
|
|
goto out;
|
||
|
|
|
||
|
|
dev_dbg(&dev->dev, "%s: #%d %s %s%s %s-> %s\n",
|
||
|
|
dev_data->irq_name,
|
||
|
|
dev_data->irq,
|
||
|
|
pci_is_enabled(dev) ? "on" : "off",
|
||
|
|
dev->msi_enabled ? "MSI" : "",
|
||
|
|
dev->msix_enabled ? "MSI/X" : "",
|
||
|
|
dev_data->isr_on ? "enable" : "disable",
|
||
|
|
enable ? "enable" : "disable");
|
||
|
|
|
||
|
|
if (enable) {
|
||
|
|
/*
|
||
|
|
* The MSI or MSI-X should not have an IRQ handler. Otherwise
|
||
|
|
* if the guest terminates we BUG_ON in free_msi_irqs.
|
||
|
|
*/
|
||
|
|
if (dev->msi_enabled || dev->msix_enabled)
|
||
|
|
goto out;
|
||
|
|
|
||
|
|
rc = request_irq(dev_data->irq,
|
||
|
|
xen_pcibk_guest_interrupt, IRQF_SHARED,
|
||
|
|
dev_data->irq_name, dev);
|
||
|
|
if (rc) {
|
||
|
|
dev_err(&dev->dev, "%s: failed to install fake IRQ " \
|
||
|
|
"handler for IRQ %d! (rc:%d)\n",
|
||
|
|
dev_data->irq_name, dev_data->irq, rc);
|
||
|
|
goto out;
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
free_irq(dev_data->irq, dev);
|
||
|
|
dev_data->irq = 0;
|
||
|
|
}
|
||
|
|
dev_data->isr_on = enable;
|
||
|
|
dev_data->ack_intr = enable;
|
||
|
|
out:
|
||
|
|
dev_dbg(&dev->dev, "%s: #%d %s %s%s %s\n",
|
||
|
|
dev_data->irq_name,
|
||
|
|
dev_data->irq,
|
||
|
|
pci_is_enabled(dev) ? "on" : "off",
|
||
|
|
dev->msi_enabled ? "MSI" : "",
|
||
|
|
dev->msix_enabled ? "MSI/X" : "",
|
||
|
|
enable ? (dev_data->isr_on ? "enabled" : "failed to enable") :
|
||
|
|
(dev_data->isr_on ? "failed to disable" : "disabled"));
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Ensure a device is "turned off" and ready to be exported.
|
||
|
|
* (Also see xen_pcibk_config_reset to ensure virtual configuration space is
|
||
|
|
* ready to be re-exported)
|
||
|
|
*/
|
||
|
|
void xen_pcibk_reset_device(struct pci_dev *dev)
|
||
|
|
{
|
||
|
|
u16 cmd;
|
||
|
|
|
||
|
|
xen_pcibk_control_isr(dev, 1 /* reset device */);
|
||
|
|
|
||
|
|
/* Disable devices (but not bridges) */
|
||
|
|
if (dev->hdr_type == PCI_HEADER_TYPE_NORMAL) {
|
||
|
|
#ifdef CONFIG_PCI_MSI
|
||
|
|
/* The guest could have been abruptly killed without
|
||
|
|
* disabling MSI/MSI-X interrupts.*/
|
||
|
|
if (dev->msix_enabled)
|
||
|
|
pci_disable_msix(dev);
|
||
|
|
if (dev->msi_enabled)
|
||
|
|
pci_disable_msi(dev);
|
||
|
|
#endif
|
||
|
|
if (pci_is_enabled(dev))
|
||
|
|
pci_disable_device(dev);
|
||
|
|
|
||
|
|
dev->is_busmaster = 0;
|
||
|
|
} else {
|
||
|
|
pci_read_config_word(dev, PCI_COMMAND, &cmd);
|
||
|
|
if (cmd & (PCI_COMMAND_INVALIDATE)) {
|
||
|
|
cmd &= ~(PCI_COMMAND_INVALIDATE);
|
||
|
|
pci_write_config_word(dev, PCI_COMMAND, cmd);
|
||
|
|
|
||
|
|
dev->is_busmaster = 0;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
#ifdef CONFIG_PCI_MSI
|
||
|
|
static
|
||
|
|
int xen_pcibk_enable_msi(struct xen_pcibk_device *pdev,
|
||
|
|
struct pci_dev *dev, struct xen_pci_op *op)
|
||
|
|
{
|
||
|
|
struct xen_pcibk_dev_data *dev_data;
|
||
|
|
int status;
|
||
|
|
|
||
|
|
if (unlikely(verbose_request))
|
||
|
|
printk(KERN_DEBUG DRV_NAME ": %s: enable MSI\n", pci_name(dev));
|
||
|
|
|
||
|
|
if (dev->msi_enabled)
|
||
|
|
status = -EALREADY;
|
||
|
|
else if (dev->msix_enabled)
|
||
|
|
status = -ENXIO;
|
||
|
|
else
|
||
|
|
status = pci_enable_msi(dev);
|
||
|
|
|
||
|
|
if (status) {
|
||
|
|
pr_warn_ratelimited("%s: error enabling MSI for guest %u: err %d\n",
|
||
|
|
pci_name(dev), pdev->xdev->otherend_id,
|
||
|
|
status);
|
||
|
|
op->value = 0;
|
||
|
|
return XEN_PCI_ERR_op_failed;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* The value the guest needs is actually the IDT vector, not the
|
||
|
|
* the local domain's IRQ number. */
|
||
|
|
|
||
|
|
op->value = dev->irq ? xen_pirq_from_irq(dev->irq) : 0;
|
||
|
|
if (unlikely(verbose_request))
|
||
|
|
printk(KERN_DEBUG DRV_NAME ": %s: MSI: %d\n", pci_name(dev),
|
||
|
|
op->value);
|
||
|
|
|
||
|
|
dev_data = pci_get_drvdata(dev);
|
||
|
|
if (dev_data)
|
||
|
|
dev_data->ack_intr = 0;
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static
|
||
|
|
int xen_pcibk_disable_msi(struct xen_pcibk_device *pdev,
|
||
|
|
struct pci_dev *dev, struct xen_pci_op *op)
|
||
|
|
{
|
||
|
|
if (unlikely(verbose_request))
|
||
|
|
printk(KERN_DEBUG DRV_NAME ": %s: disable MSI\n",
|
||
|
|
pci_name(dev));
|
||
|
|
|
||
|
|
if (dev->msi_enabled) {
|
||
|
|
struct xen_pcibk_dev_data *dev_data;
|
||
|
|
|
||
|
|
pci_disable_msi(dev);
|
||
|
|
|
||
|
|
dev_data = pci_get_drvdata(dev);
|
||
|
|
if (dev_data)
|
||
|
|
dev_data->ack_intr = 1;
|
||
|
|
}
|
||
|
|
op->value = dev->irq ? xen_pirq_from_irq(dev->irq) : 0;
|
||
|
|
if (unlikely(verbose_request))
|
||
|
|
printk(KERN_DEBUG DRV_NAME ": %s: MSI: %d\n", pci_name(dev),
|
||
|
|
op->value);
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static
|
||
|
|
int xen_pcibk_enable_msix(struct xen_pcibk_device *pdev,
|
||
|
|
struct pci_dev *dev, struct xen_pci_op *op)
|
||
|
|
{
|
||
|
|
struct xen_pcibk_dev_data *dev_data;
|
||
|
|
int i, result;
|
||
|
|
struct msix_entry *entries;
|
||
|
|
u16 cmd;
|
||
|
|
|
||
|
|
if (unlikely(verbose_request))
|
||
|
|
printk(KERN_DEBUG DRV_NAME ": %s: enable MSI-X\n",
|
||
|
|
pci_name(dev));
|
||
|
|
|
||
|
|
if (op->value > SH_INFO_MAX_VEC)
|
||
|
|
return -EINVAL;
|
||
|
|
|
||
|
|
if (dev->msix_enabled)
|
||
|
|
return -EALREADY;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* PCI_COMMAND_MEMORY must be enabled, otherwise we may not be able
|
||
|
|
* to access the BARs where the MSI-X entries reside.
|
||
|
|
* But VF devices are unique in which the PF needs to be checked.
|
||
|
|
*/
|
||
|
|
pci_read_config_word(pci_physfn(dev), PCI_COMMAND, &cmd);
|
||
|
|
if (dev->msi_enabled || !(cmd & PCI_COMMAND_MEMORY))
|
||
|
|
return -ENXIO;
|
||
|
|
|
||
|
|
entries = kmalloc(op->value * sizeof(*entries), GFP_KERNEL);
|
||
|
|
if (entries == NULL)
|
||
|
|
return -ENOMEM;
|
||
|
|
|
||
|
|
for (i = 0; i < op->value; i++) {
|
||
|
|
entries[i].entry = op->msix_entries[i].entry;
|
||
|
|
entries[i].vector = op->msix_entries[i].vector;
|
||
|
|
}
|
||
|
|
|
||
|
|
result = pci_enable_msix_exact(dev, entries, op->value);
|
||
|
|
if (result == 0) {
|
||
|
|
for (i = 0; i < op->value; i++) {
|
||
|
|
op->msix_entries[i].entry = entries[i].entry;
|
||
|
|
if (entries[i].vector) {
|
||
|
|
op->msix_entries[i].vector =
|
||
|
|
xen_pirq_from_irq(entries[i].vector);
|
||
|
|
if (unlikely(verbose_request))
|
||
|
|
printk(KERN_DEBUG DRV_NAME ": %s: " \
|
||
|
|
"MSI-X[%d]: %d\n",
|
||
|
|
pci_name(dev), i,
|
||
|
|
op->msix_entries[i].vector);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
} else
|
||
|
|
pr_warn_ratelimited("%s: error enabling MSI-X for guest %u: err %d!\n",
|
||
|
|
pci_name(dev), pdev->xdev->otherend_id,
|
||
|
|
result);
|
||
|
|
kfree(entries);
|
||
|
|
|
||
|
|
op->value = result;
|
||
|
|
dev_data = pci_get_drvdata(dev);
|
||
|
|
if (dev_data)
|
||
|
|
dev_data->ack_intr = 0;
|
||
|
|
|
||
|
|
return result > 0 ? 0 : result;
|
||
|
|
}
|
||
|
|
|
||
|
|
static
|
||
|
|
int xen_pcibk_disable_msix(struct xen_pcibk_device *pdev,
|
||
|
|
struct pci_dev *dev, struct xen_pci_op *op)
|
||
|
|
{
|
||
|
|
if (unlikely(verbose_request))
|
||
|
|
printk(KERN_DEBUG DRV_NAME ": %s: disable MSI-X\n",
|
||
|
|
pci_name(dev));
|
||
|
|
|
||
|
|
if (dev->msix_enabled) {
|
||
|
|
struct xen_pcibk_dev_data *dev_data;
|
||
|
|
|
||
|
|
pci_disable_msix(dev);
|
||
|
|
|
||
|
|
dev_data = pci_get_drvdata(dev);
|
||
|
|
if (dev_data)
|
||
|
|
dev_data->ack_intr = 1;
|
||
|
|
}
|
||
|
|
/*
|
||
|
|
* SR-IOV devices (which don't have any legacy IRQ) have
|
||
|
|
* an undefined IRQ value of zero.
|
||
|
|
*/
|
||
|
|
op->value = dev->irq ? xen_pirq_from_irq(dev->irq) : 0;
|
||
|
|
if (unlikely(verbose_request))
|
||
|
|
printk(KERN_DEBUG DRV_NAME ": %s: MSI-X: %d\n",
|
||
|
|
pci_name(dev), op->value);
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
|
||
|
|
static inline bool xen_pcibk_test_op_pending(struct xen_pcibk_device *pdev)
|
||
|
|
{
|
||
|
|
return test_bit(_XEN_PCIF_active,
|
||
|
|
(unsigned long *)&pdev->sh_info->flags) &&
|
||
|
|
!test_and_set_bit(_PDEVF_op_active, &pdev->flags);
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Now the same evtchn is used for both pcifront conf_read_write request
|
||
|
|
* as well as pcie aer front end ack. We use a new work_queue to schedule
|
||
|
|
* xen_pcibk conf_read_write service for avoiding confict with aer_core
|
||
|
|
* do_recovery job which also use the system default work_queue
|
||
|
|
*/
|
||
|
|
static void xen_pcibk_test_and_schedule_op(struct xen_pcibk_device *pdev)
|
||
|
|
{
|
||
|
|
bool eoi = true;
|
||
|
|
|
||
|
|
/* Check that frontend is requesting an operation and that we are not
|
||
|
|
* already processing a request */
|
||
|
|
if (xen_pcibk_test_op_pending(pdev)) {
|
||
|
|
schedule_work(&pdev->op_work);
|
||
|
|
eoi = false;
|
||
|
|
}
|
||
|
|
/*_XEN_PCIB_active should have been cleared by pcifront. And also make
|
||
|
|
sure xen_pcibk is waiting for ack by checking _PCIB_op_pending*/
|
||
|
|
if (!test_bit(_XEN_PCIB_active, (unsigned long *)&pdev->sh_info->flags)
|
||
|
|
&& test_bit(_PCIB_op_pending, &pdev->flags)) {
|
||
|
|
wake_up(&xen_pcibk_aer_wait_queue);
|
||
|
|
eoi = false;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* EOI if there was nothing to do. */
|
||
|
|
if (eoi)
|
||
|
|
xen_pcibk_lateeoi(pdev, XEN_EOI_FLAG_SPURIOUS);
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Performing the configuration space reads/writes must not be done in atomic
|
||
|
|
* context because some of the pci_* functions can sleep (mostly due to ACPI
|
||
|
|
* use of semaphores). This function is intended to be called from a work
|
||
|
|
* queue in process context taking a struct xen_pcibk_device as a parameter */
|
||
|
|
|
||
|
|
static void xen_pcibk_do_one_op(struct xen_pcibk_device *pdev)
|
||
|
|
{
|
||
|
|
struct pci_dev *dev;
|
||
|
|
struct xen_pcibk_dev_data *dev_data = NULL;
|
||
|
|
struct xen_pci_op *op = &pdev->op;
|
||
|
|
int test_intx = 0;
|
||
|
|
#ifdef CONFIG_PCI_MSI
|
||
|
|
unsigned int nr = 0;
|
||
|
|
#endif
|
||
|
|
|
||
|
|
*op = pdev->sh_info->op;
|
||
|
|
barrier();
|
||
|
|
dev = xen_pcibk_get_pci_dev(pdev, op->domain, op->bus, op->devfn);
|
||
|
|
|
||
|
|
if (dev == NULL)
|
||
|
|
op->err = XEN_PCI_ERR_dev_not_found;
|
||
|
|
else {
|
||
|
|
dev_data = pci_get_drvdata(dev);
|
||
|
|
if (dev_data)
|
||
|
|
test_intx = dev_data->enable_intx;
|
||
|
|
switch (op->cmd) {
|
||
|
|
case XEN_PCI_OP_conf_read:
|
||
|
|
op->err = xen_pcibk_config_read(dev,
|
||
|
|
op->offset, op->size, &op->value);
|
||
|
|
break;
|
||
|
|
case XEN_PCI_OP_conf_write:
|
||
|
|
op->err = xen_pcibk_config_write(dev,
|
||
|
|
op->offset, op->size, op->value);
|
||
|
|
break;
|
||
|
|
#ifdef CONFIG_PCI_MSI
|
||
|
|
case XEN_PCI_OP_enable_msi:
|
||
|
|
op->err = xen_pcibk_enable_msi(pdev, dev, op);
|
||
|
|
break;
|
||
|
|
case XEN_PCI_OP_disable_msi:
|
||
|
|
op->err = xen_pcibk_disable_msi(pdev, dev, op);
|
||
|
|
break;
|
||
|
|
case XEN_PCI_OP_enable_msix:
|
||
|
|
nr = op->value;
|
||
|
|
op->err = xen_pcibk_enable_msix(pdev, dev, op);
|
||
|
|
break;
|
||
|
|
case XEN_PCI_OP_disable_msix:
|
||
|
|
op->err = xen_pcibk_disable_msix(pdev, dev, op);
|
||
|
|
break;
|
||
|
|
#endif
|
||
|
|
default:
|
||
|
|
op->err = XEN_PCI_ERR_not_implemented;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
if (!op->err && dev && dev_data) {
|
||
|
|
/* Transition detected */
|
||
|
|
if ((dev_data->enable_intx != test_intx))
|
||
|
|
xen_pcibk_control_isr(dev, 0 /* no reset */);
|
||
|
|
}
|
||
|
|
pdev->sh_info->op.err = op->err;
|
||
|
|
pdev->sh_info->op.value = op->value;
|
||
|
|
#ifdef CONFIG_PCI_MSI
|
||
|
|
if (op->cmd == XEN_PCI_OP_enable_msix && op->err == 0) {
|
||
|
|
unsigned int i;
|
||
|
|
|
||
|
|
for (i = 0; i < nr; i++)
|
||
|
|
pdev->sh_info->op.msix_entries[i].vector =
|
||
|
|
op->msix_entries[i].vector;
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
/* Tell the driver domain that we're done. */
|
||
|
|
wmb();
|
||
|
|
clear_bit(_XEN_PCIF_active, (unsigned long *)&pdev->sh_info->flags);
|
||
|
|
notify_remote_via_irq(pdev->evtchn_irq);
|
||
|
|
|
||
|
|
/* Mark that we're done. */
|
||
|
|
smp_mb__before_atomic(); /* /after/ clearing PCIF_active */
|
||
|
|
clear_bit(_PDEVF_op_active, &pdev->flags);
|
||
|
|
smp_mb__after_atomic(); /* /before/ final check for work */
|
||
|
|
}
|
||
|
|
|
||
|
|
void xen_pcibk_do_op(struct work_struct *data)
|
||
|
|
{
|
||
|
|
struct xen_pcibk_device *pdev =
|
||
|
|
container_of(data, struct xen_pcibk_device, op_work);
|
||
|
|
|
||
|
|
do {
|
||
|
|
xen_pcibk_do_one_op(pdev);
|
||
|
|
} while (xen_pcibk_test_op_pending(pdev));
|
||
|
|
|
||
|
|
xen_pcibk_lateeoi(pdev, 0);
|
||
|
|
}
|
||
|
|
|
||
|
|
irqreturn_t xen_pcibk_handle_event(int irq, void *dev_id)
|
||
|
|
{
|
||
|
|
struct xen_pcibk_device *pdev = dev_id;
|
||
|
|
bool eoi;
|
||
|
|
|
||
|
|
/* IRQs might come in before pdev->evtchn_irq is written. */
|
||
|
|
if (unlikely(pdev->evtchn_irq != irq))
|
||
|
|
pdev->evtchn_irq = irq;
|
||
|
|
|
||
|
|
eoi = test_and_set_bit(_EOI_pending, &pdev->flags);
|
||
|
|
WARN(eoi, "IRQ while EOI pending\n");
|
||
|
|
|
||
|
|
xen_pcibk_test_and_schedule_op(pdev);
|
||
|
|
|
||
|
|
return IRQ_HANDLED;
|
||
|
|
}
|
||
|
|
static irqreturn_t xen_pcibk_guest_interrupt(int irq, void *dev_id)
|
||
|
|
{
|
||
|
|
struct pci_dev *dev = (struct pci_dev *)dev_id;
|
||
|
|
struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev);
|
||
|
|
|
||
|
|
if (dev_data->isr_on && dev_data->ack_intr) {
|
||
|
|
dev_data->handled++;
|
||
|
|
if ((dev_data->handled % 1000) == 0) {
|
||
|
|
if (xen_test_irq_shared(irq)) {
|
||
|
|
pr_info("%s IRQ line is not shared "
|
||
|
|
"with other domains. Turning ISR off\n",
|
||
|
|
dev_data->irq_name);
|
||
|
|
dev_data->ack_intr = 0;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return IRQ_HANDLED;
|
||
|
|
}
|
||
|
|
return IRQ_NONE;
|
||
|
|
}
|