forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
1182 lines
27 KiB
1182 lines
27 KiB
// SPDX-License-Identifier: GPL-2.0 |
|
/* |
|
* Xen PCI Frontend |
|
* |
|
* Author: Ryan Wilson <[email protected]> |
|
*/ |
|
#include <linux/module.h> |
|
#include <linux/init.h> |
|
#include <linux/mm.h> |
|
#include <xen/xenbus.h> |
|
#include <xen/events.h> |
|
#include <xen/grant_table.h> |
|
#include <xen/page.h> |
|
#include <linux/spinlock.h> |
|
#include <linux/pci.h> |
|
#include <linux/msi.h> |
|
#include <xen/interface/io/pciif.h> |
|
#include <asm/xen/pci.h> |
|
#include <linux/interrupt.h> |
|
#include <linux/atomic.h> |
|
#include <linux/workqueue.h> |
|
#include <linux/bitops.h> |
|
#include <linux/time.h> |
|
#include <linux/ktime.h> |
|
#include <linux/swiotlb.h> |
|
#include <xen/platform_pci.h> |
|
|
|
#include <asm/xen/swiotlb-xen.h> |
|
|
|
#define INVALID_EVTCHN (-1) |
|
|
|
struct pci_bus_entry { |
|
struct list_head list; |
|
struct pci_bus *bus; |
|
}; |
|
|
|
#define _PDEVB_op_active (0) |
|
#define PDEVB_op_active (1 << (_PDEVB_op_active)) |
|
|
|
struct pcifront_device { |
|
struct xenbus_device *xdev; |
|
struct list_head root_buses; |
|
|
|
int evtchn; |
|
grant_ref_t gnt_ref; |
|
|
|
int irq; |
|
|
|
/* Lock this when doing any operations in sh_info */ |
|
spinlock_t sh_info_lock; |
|
struct xen_pci_sharedinfo *sh_info; |
|
struct work_struct op_work; |
|
unsigned long flags; |
|
|
|
}; |
|
|
|
struct pcifront_sd { |
|
struct pci_sysdata sd; |
|
struct pcifront_device *pdev; |
|
}; |
|
|
|
static inline struct pcifront_device * |
|
pcifront_get_pdev(struct pcifront_sd *sd) |
|
{ |
|
return sd->pdev; |
|
} |
|
|
|
static inline void pcifront_init_sd(struct pcifront_sd *sd, |
|
unsigned int domain, unsigned int bus, |
|
struct pcifront_device *pdev) |
|
{ |
|
/* Because we do not expose that information via XenBus. */ |
|
sd->sd.node = first_online_node; |
|
sd->sd.domain = domain; |
|
sd->pdev = pdev; |
|
} |
|
|
|
static DEFINE_SPINLOCK(pcifront_dev_lock); |
|
static struct pcifront_device *pcifront_dev; |
|
|
|
static int errno_to_pcibios_err(int errno) |
|
{ |
|
switch (errno) { |
|
case XEN_PCI_ERR_success: |
|
return PCIBIOS_SUCCESSFUL; |
|
|
|
case XEN_PCI_ERR_dev_not_found: |
|
return PCIBIOS_DEVICE_NOT_FOUND; |
|
|
|
case XEN_PCI_ERR_invalid_offset: |
|
case XEN_PCI_ERR_op_failed: |
|
return PCIBIOS_BAD_REGISTER_NUMBER; |
|
|
|
case XEN_PCI_ERR_not_implemented: |
|
return PCIBIOS_FUNC_NOT_SUPPORTED; |
|
|
|
case XEN_PCI_ERR_access_denied: |
|
return PCIBIOS_SET_FAILED; |
|
} |
|
return errno; |
|
} |
|
|
|
static inline void schedule_pcifront_aer_op(struct pcifront_device *pdev) |
|
{ |
|
if (test_bit(_XEN_PCIB_active, (unsigned long *)&pdev->sh_info->flags) |
|
&& !test_and_set_bit(_PDEVB_op_active, &pdev->flags)) { |
|
dev_dbg(&pdev->xdev->dev, "schedule aer frontend job\n"); |
|
schedule_work(&pdev->op_work); |
|
} |
|
} |
|
|
|
static int do_pci_op(struct pcifront_device *pdev, struct xen_pci_op *op) |
|
{ |
|
int err = 0; |
|
struct xen_pci_op *active_op = &pdev->sh_info->op; |
|
unsigned long irq_flags; |
|
evtchn_port_t port = pdev->evtchn; |
|
unsigned irq = pdev->irq; |
|
s64 ns, ns_timeout; |
|
|
|
spin_lock_irqsave(&pdev->sh_info_lock, irq_flags); |
|
|
|
memcpy(active_op, op, sizeof(struct xen_pci_op)); |
|
|
|
/* Go */ |
|
wmb(); |
|
set_bit(_XEN_PCIF_active, (unsigned long *)&pdev->sh_info->flags); |
|
notify_remote_via_evtchn(port); |
|
|
|
/* |
|
* We set a poll timeout of 3 seconds but give up on return after |
|
* 2 seconds. It is better to time out too late rather than too early |
|
* (in the latter case we end up continually re-executing poll() with a |
|
* timeout in the past). 1s difference gives plenty of slack for error. |
|
*/ |
|
ns_timeout = ktime_get_ns() + 2 * (s64)NSEC_PER_SEC; |
|
|
|
xen_clear_irq_pending(irq); |
|
|
|
while (test_bit(_XEN_PCIF_active, |
|
(unsigned long *)&pdev->sh_info->flags)) { |
|
xen_poll_irq_timeout(irq, jiffies + 3*HZ); |
|
xen_clear_irq_pending(irq); |
|
ns = ktime_get_ns(); |
|
if (ns > ns_timeout) { |
|
dev_err(&pdev->xdev->dev, |
|
"pciback not responding!!!\n"); |
|
clear_bit(_XEN_PCIF_active, |
|
(unsigned long *)&pdev->sh_info->flags); |
|
err = XEN_PCI_ERR_dev_not_found; |
|
goto out; |
|
} |
|
} |
|
|
|
/* |
|
* We might lose backend service request since we |
|
* reuse same evtchn with pci_conf backend response. So re-schedule |
|
* aer pcifront service. |
|
*/ |
|
if (test_bit(_XEN_PCIB_active, |
|
(unsigned long *)&pdev->sh_info->flags)) { |
|
dev_err(&pdev->xdev->dev, |
|
"schedule aer pcifront service\n"); |
|
schedule_pcifront_aer_op(pdev); |
|
} |
|
|
|
memcpy(op, active_op, sizeof(struct xen_pci_op)); |
|
|
|
err = op->err; |
|
out: |
|
spin_unlock_irqrestore(&pdev->sh_info_lock, irq_flags); |
|
return err; |
|
} |
|
|
|
/* Access to this function is spinlocked in drivers/pci/access.c */ |
|
static int pcifront_bus_read(struct pci_bus *bus, unsigned int devfn, |
|
int where, int size, u32 *val) |
|
{ |
|
int err = 0; |
|
struct xen_pci_op op = { |
|
.cmd = XEN_PCI_OP_conf_read, |
|
.domain = pci_domain_nr(bus), |
|
.bus = bus->number, |
|
.devfn = devfn, |
|
.offset = where, |
|
.size = size, |
|
}; |
|
struct pcifront_sd *sd = bus->sysdata; |
|
struct pcifront_device *pdev = pcifront_get_pdev(sd); |
|
|
|
dev_dbg(&pdev->xdev->dev, |
|
"read dev=%04x:%02x:%02x.%d - offset %x size %d\n", |
|
pci_domain_nr(bus), bus->number, PCI_SLOT(devfn), |
|
PCI_FUNC(devfn), where, size); |
|
|
|
err = do_pci_op(pdev, &op); |
|
|
|
if (likely(!err)) { |
|
dev_dbg(&pdev->xdev->dev, "read got back value %x\n", |
|
op.value); |
|
|
|
*val = op.value; |
|
} else if (err == -ENODEV) { |
|
/* No device here, pretend that it just returned 0 */ |
|
err = 0; |
|
*val = 0; |
|
} |
|
|
|
return errno_to_pcibios_err(err); |
|
} |
|
|
|
/* Access to this function is spinlocked in drivers/pci/access.c */ |
|
static int pcifront_bus_write(struct pci_bus *bus, unsigned int devfn, |
|
int where, int size, u32 val) |
|
{ |
|
struct xen_pci_op op = { |
|
.cmd = XEN_PCI_OP_conf_write, |
|
.domain = pci_domain_nr(bus), |
|
.bus = bus->number, |
|
.devfn = devfn, |
|
.offset = where, |
|
.size = size, |
|
.value = val, |
|
}; |
|
struct pcifront_sd *sd = bus->sysdata; |
|
struct pcifront_device *pdev = pcifront_get_pdev(sd); |
|
|
|
dev_dbg(&pdev->xdev->dev, |
|
"write dev=%04x:%02x:%02x.%d - offset %x size %d val %x\n", |
|
pci_domain_nr(bus), bus->number, |
|
PCI_SLOT(devfn), PCI_FUNC(devfn), where, size, val); |
|
|
|
return errno_to_pcibios_err(do_pci_op(pdev, &op)); |
|
} |
|
|
|
static struct pci_ops pcifront_bus_ops = { |
|
.read = pcifront_bus_read, |
|
.write = pcifront_bus_write, |
|
}; |
|
|
|
#ifdef CONFIG_PCI_MSI |
|
static int pci_frontend_enable_msix(struct pci_dev *dev, |
|
int vector[], int nvec) |
|
{ |
|
int err; |
|
int i; |
|
struct xen_pci_op op = { |
|
.cmd = XEN_PCI_OP_enable_msix, |
|
.domain = pci_domain_nr(dev->bus), |
|
.bus = dev->bus->number, |
|
.devfn = dev->devfn, |
|
.value = nvec, |
|
}; |
|
struct pcifront_sd *sd = dev->bus->sysdata; |
|
struct pcifront_device *pdev = pcifront_get_pdev(sd); |
|
struct msi_desc *entry; |
|
|
|
if (nvec > SH_INFO_MAX_VEC) { |
|
pci_err(dev, "too many vectors (0x%x) for PCI frontend:" |
|
" Increase SH_INFO_MAX_VEC\n", nvec); |
|
return -EINVAL; |
|
} |
|
|
|
i = 0; |
|
for_each_pci_msi_entry(entry, dev) { |
|
op.msix_entries[i].entry = entry->msi_attrib.entry_nr; |
|
/* Vector is useless at this point. */ |
|
op.msix_entries[i].vector = -1; |
|
i++; |
|
} |
|
|
|
err = do_pci_op(pdev, &op); |
|
|
|
if (likely(!err)) { |
|
if (likely(!op.value)) { |
|
/* we get the result */ |
|
for (i = 0; i < nvec; i++) { |
|
if (op.msix_entries[i].vector <= 0) { |
|
pci_warn(dev, "MSI-X entry %d is invalid: %d!\n", |
|
i, op.msix_entries[i].vector); |
|
err = -EINVAL; |
|
vector[i] = -1; |
|
continue; |
|
} |
|
vector[i] = op.msix_entries[i].vector; |
|
} |
|
} else { |
|
pr_info("enable msix get value %x\n", op.value); |
|
err = op.value; |
|
} |
|
} else { |
|
pci_err(dev, "enable msix get err %x\n", err); |
|
} |
|
return err; |
|
} |
|
|
|
static void pci_frontend_disable_msix(struct pci_dev *dev) |
|
{ |
|
int err; |
|
struct xen_pci_op op = { |
|
.cmd = XEN_PCI_OP_disable_msix, |
|
.domain = pci_domain_nr(dev->bus), |
|
.bus = dev->bus->number, |
|
.devfn = dev->devfn, |
|
}; |
|
struct pcifront_sd *sd = dev->bus->sysdata; |
|
struct pcifront_device *pdev = pcifront_get_pdev(sd); |
|
|
|
err = do_pci_op(pdev, &op); |
|
|
|
/* What should do for error ? */ |
|
if (err) |
|
pci_err(dev, "pci_disable_msix get err %x\n", err); |
|
} |
|
|
|
static int pci_frontend_enable_msi(struct pci_dev *dev, int vector[]) |
|
{ |
|
int err; |
|
struct xen_pci_op op = { |
|
.cmd = XEN_PCI_OP_enable_msi, |
|
.domain = pci_domain_nr(dev->bus), |
|
.bus = dev->bus->number, |
|
.devfn = dev->devfn, |
|
}; |
|
struct pcifront_sd *sd = dev->bus->sysdata; |
|
struct pcifront_device *pdev = pcifront_get_pdev(sd); |
|
|
|
err = do_pci_op(pdev, &op); |
|
if (likely(!err)) { |
|
vector[0] = op.value; |
|
if (op.value <= 0) { |
|
pci_warn(dev, "MSI entry is invalid: %d!\n", |
|
op.value); |
|
err = -EINVAL; |
|
vector[0] = -1; |
|
} |
|
} else { |
|
pci_err(dev, "pci frontend enable msi failed for dev " |
|
"%x:%x\n", op.bus, op.devfn); |
|
err = -EINVAL; |
|
} |
|
return err; |
|
} |
|
|
|
static void pci_frontend_disable_msi(struct pci_dev *dev) |
|
{ |
|
int err; |
|
struct xen_pci_op op = { |
|
.cmd = XEN_PCI_OP_disable_msi, |
|
.domain = pci_domain_nr(dev->bus), |
|
.bus = dev->bus->number, |
|
.devfn = dev->devfn, |
|
}; |
|
struct pcifront_sd *sd = dev->bus->sysdata; |
|
struct pcifront_device *pdev = pcifront_get_pdev(sd); |
|
|
|
err = do_pci_op(pdev, &op); |
|
if (err == XEN_PCI_ERR_dev_not_found) { |
|
/* XXX No response from backend, what shall we do? */ |
|
pr_info("get no response from backend for disable MSI\n"); |
|
return; |
|
} |
|
if (err) |
|
/* how can pciback notify us fail? */ |
|
pr_info("get fake response from backend\n"); |
|
} |
|
|
|
static struct xen_pci_frontend_ops pci_frontend_ops = { |
|
.enable_msi = pci_frontend_enable_msi, |
|
.disable_msi = pci_frontend_disable_msi, |
|
.enable_msix = pci_frontend_enable_msix, |
|
.disable_msix = pci_frontend_disable_msix, |
|
}; |
|
|
|
static void pci_frontend_registrar(int enable) |
|
{ |
|
if (enable) |
|
xen_pci_frontend = &pci_frontend_ops; |
|
else |
|
xen_pci_frontend = NULL; |
|
}; |
|
#else |
|
static inline void pci_frontend_registrar(int enable) { }; |
|
#endif /* CONFIG_PCI_MSI */ |
|
|
|
/* Claim resources for the PCI frontend as-is, backend won't allow changes */ |
|
static int pcifront_claim_resource(struct pci_dev *dev, void *data) |
|
{ |
|
struct pcifront_device *pdev = data; |
|
int i; |
|
struct resource *r; |
|
|
|
for (i = 0; i < PCI_NUM_RESOURCES; i++) { |
|
r = &dev->resource[i]; |
|
|
|
if (!r->parent && r->start && r->flags) { |
|
dev_info(&pdev->xdev->dev, "claiming resource %s/%d\n", |
|
pci_name(dev), i); |
|
if (pci_claim_resource(dev, i)) { |
|
dev_err(&pdev->xdev->dev, "Could not claim resource %s/%d! " |
|
"Device offline. Try using e820_host=1 in the guest config.\n", |
|
pci_name(dev), i); |
|
} |
|
} |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static int pcifront_scan_bus(struct pcifront_device *pdev, |
|
unsigned int domain, unsigned int bus, |
|
struct pci_bus *b) |
|
{ |
|
struct pci_dev *d; |
|
unsigned int devfn; |
|
|
|
/* Scan the bus for functions and add. |
|
* We omit handling of PCI bridge attachment because pciback prevents |
|
* bridges from being exported. |
|
*/ |
|
for (devfn = 0; devfn < 0x100; devfn++) { |
|
d = pci_get_slot(b, devfn); |
|
if (d) { |
|
/* Device is already known. */ |
|
pci_dev_put(d); |
|
continue; |
|
} |
|
|
|
d = pci_scan_single_device(b, devfn); |
|
if (d) |
|
dev_info(&pdev->xdev->dev, "New device on " |
|
"%04x:%02x:%02x.%d found.\n", domain, bus, |
|
PCI_SLOT(devfn), PCI_FUNC(devfn)); |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static int pcifront_scan_root(struct pcifront_device *pdev, |
|
unsigned int domain, unsigned int bus) |
|
{ |
|
struct pci_bus *b; |
|
LIST_HEAD(resources); |
|
struct pcifront_sd *sd = NULL; |
|
struct pci_bus_entry *bus_entry = NULL; |
|
int err = 0; |
|
static struct resource busn_res = { |
|
.start = 0, |
|
.end = 255, |
|
.flags = IORESOURCE_BUS, |
|
}; |
|
|
|
#ifndef CONFIG_PCI_DOMAINS |
|
if (domain != 0) { |
|
dev_err(&pdev->xdev->dev, |
|
"PCI Root in non-zero PCI Domain! domain=%d\n", domain); |
|
dev_err(&pdev->xdev->dev, |
|
"Please compile with CONFIG_PCI_DOMAINS\n"); |
|
err = -EINVAL; |
|
goto err_out; |
|
} |
|
#endif |
|
|
|
dev_info(&pdev->xdev->dev, "Creating PCI Frontend Bus %04x:%02x\n", |
|
domain, bus); |
|
|
|
bus_entry = kzalloc(sizeof(*bus_entry), GFP_KERNEL); |
|
sd = kzalloc(sizeof(*sd), GFP_KERNEL); |
|
if (!bus_entry || !sd) { |
|
err = -ENOMEM; |
|
goto err_out; |
|
} |
|
pci_add_resource(&resources, &ioport_resource); |
|
pci_add_resource(&resources, &iomem_resource); |
|
pci_add_resource(&resources, &busn_res); |
|
pcifront_init_sd(sd, domain, bus, pdev); |
|
|
|
pci_lock_rescan_remove(); |
|
|
|
b = pci_scan_root_bus(&pdev->xdev->dev, bus, |
|
&pcifront_bus_ops, sd, &resources); |
|
if (!b) { |
|
dev_err(&pdev->xdev->dev, |
|
"Error creating PCI Frontend Bus!\n"); |
|
err = -ENOMEM; |
|
pci_unlock_rescan_remove(); |
|
pci_free_resource_list(&resources); |
|
goto err_out; |
|
} |
|
|
|
bus_entry->bus = b; |
|
|
|
list_add(&bus_entry->list, &pdev->root_buses); |
|
|
|
/* pci_scan_root_bus skips devices which do not have a |
|
* devfn==0. The pcifront_scan_bus enumerates all devfn. */ |
|
err = pcifront_scan_bus(pdev, domain, bus, b); |
|
|
|
/* Claim resources before going "live" with our devices */ |
|
pci_walk_bus(b, pcifront_claim_resource, pdev); |
|
|
|
/* Create SysFS and notify udev of the devices. Aka: "going live" */ |
|
pci_bus_add_devices(b); |
|
|
|
pci_unlock_rescan_remove(); |
|
return err; |
|
|
|
err_out: |
|
kfree(bus_entry); |
|
kfree(sd); |
|
|
|
return err; |
|
} |
|
|
|
static int pcifront_rescan_root(struct pcifront_device *pdev, |
|
unsigned int domain, unsigned int bus) |
|
{ |
|
int err; |
|
struct pci_bus *b; |
|
|
|
#ifndef CONFIG_PCI_DOMAINS |
|
if (domain != 0) { |
|
dev_err(&pdev->xdev->dev, |
|
"PCI Root in non-zero PCI Domain! domain=%d\n", domain); |
|
dev_err(&pdev->xdev->dev, |
|
"Please compile with CONFIG_PCI_DOMAINS\n"); |
|
return -EINVAL; |
|
} |
|
#endif |
|
|
|
dev_info(&pdev->xdev->dev, "Rescanning PCI Frontend Bus %04x:%02x\n", |
|
domain, bus); |
|
|
|
b = pci_find_bus(domain, bus); |
|
if (!b) |
|
/* If the bus is unknown, create it. */ |
|
return pcifront_scan_root(pdev, domain, bus); |
|
|
|
err = pcifront_scan_bus(pdev, domain, bus, b); |
|
|
|
/* Claim resources before going "live" with our devices */ |
|
pci_walk_bus(b, pcifront_claim_resource, pdev); |
|
|
|
/* Create SysFS and notify udev of the devices. Aka: "going live" */ |
|
pci_bus_add_devices(b); |
|
|
|
return err; |
|
} |
|
|
|
static void free_root_bus_devs(struct pci_bus *bus) |
|
{ |
|
struct pci_dev *dev; |
|
|
|
while (!list_empty(&bus->devices)) { |
|
dev = container_of(bus->devices.next, struct pci_dev, |
|
bus_list); |
|
pci_dbg(dev, "removing device\n"); |
|
pci_stop_and_remove_bus_device(dev); |
|
} |
|
} |
|
|
|
static void pcifront_free_roots(struct pcifront_device *pdev) |
|
{ |
|
struct pci_bus_entry *bus_entry, *t; |
|
|
|
dev_dbg(&pdev->xdev->dev, "cleaning up root buses\n"); |
|
|
|
pci_lock_rescan_remove(); |
|
list_for_each_entry_safe(bus_entry, t, &pdev->root_buses, list) { |
|
list_del(&bus_entry->list); |
|
|
|
free_root_bus_devs(bus_entry->bus); |
|
|
|
kfree(bus_entry->bus->sysdata); |
|
|
|
device_unregister(bus_entry->bus->bridge); |
|
pci_remove_bus(bus_entry->bus); |
|
|
|
kfree(bus_entry); |
|
} |
|
pci_unlock_rescan_remove(); |
|
} |
|
|
|
static pci_ers_result_t pcifront_common_process(int cmd, |
|
struct pcifront_device *pdev, |
|
pci_channel_state_t state) |
|
{ |
|
pci_ers_result_t result; |
|
struct pci_driver *pdrv; |
|
int bus = pdev->sh_info->aer_op.bus; |
|
int devfn = pdev->sh_info->aer_op.devfn; |
|
int domain = pdev->sh_info->aer_op.domain; |
|
struct pci_dev *pcidev; |
|
int flag = 0; |
|
|
|
dev_dbg(&pdev->xdev->dev, |
|
"pcifront AER process: cmd %x (bus:%x, devfn%x)", |
|
cmd, bus, devfn); |
|
result = PCI_ERS_RESULT_NONE; |
|
|
|
pcidev = pci_get_domain_bus_and_slot(domain, bus, devfn); |
|
if (!pcidev || !pcidev->driver) { |
|
dev_err(&pdev->xdev->dev, "device or AER driver is NULL\n"); |
|
pci_dev_put(pcidev); |
|
return result; |
|
} |
|
pdrv = pcidev->driver; |
|
|
|
if (pdrv) { |
|
if (pdrv->err_handler && pdrv->err_handler->error_detected) { |
|
pci_dbg(pcidev, "trying to call AER service\n"); |
|
if (pcidev) { |
|
flag = 1; |
|
switch (cmd) { |
|
case XEN_PCI_OP_aer_detected: |
|
result = pdrv->err_handler-> |
|
error_detected(pcidev, state); |
|
break; |
|
case XEN_PCI_OP_aer_mmio: |
|
result = pdrv->err_handler-> |
|
mmio_enabled(pcidev); |
|
break; |
|
case XEN_PCI_OP_aer_slotreset: |
|
result = pdrv->err_handler-> |
|
slot_reset(pcidev); |
|
break; |
|
case XEN_PCI_OP_aer_resume: |
|
pdrv->err_handler->resume(pcidev); |
|
break; |
|
default: |
|
dev_err(&pdev->xdev->dev, |
|
"bad request in aer recovery " |
|
"operation!\n"); |
|
|
|
} |
|
} |
|
} |
|
} |
|
if (!flag) |
|
result = PCI_ERS_RESULT_NONE; |
|
|
|
return result; |
|
} |
|
|
|
|
|
static void pcifront_do_aer(struct work_struct *data) |
|
{ |
|
struct pcifront_device *pdev = |
|
container_of(data, struct pcifront_device, op_work); |
|
int cmd = pdev->sh_info->aer_op.cmd; |
|
pci_channel_state_t state = |
|
(pci_channel_state_t)pdev->sh_info->aer_op.err; |
|
|
|
/*If a pci_conf op is in progress, |
|
we have to wait until it is done before service aer op*/ |
|
dev_dbg(&pdev->xdev->dev, |
|
"pcifront service aer bus %x devfn %x\n", |
|
pdev->sh_info->aer_op.bus, pdev->sh_info->aer_op.devfn); |
|
|
|
pdev->sh_info->aer_op.err = pcifront_common_process(cmd, pdev, state); |
|
|
|
/* Post the operation to the guest. */ |
|
wmb(); |
|
clear_bit(_XEN_PCIB_active, (unsigned long *)&pdev->sh_info->flags); |
|
notify_remote_via_evtchn(pdev->evtchn); |
|
|
|
/*in case of we lost an aer request in four lines time_window*/ |
|
smp_mb__before_atomic(); |
|
clear_bit(_PDEVB_op_active, &pdev->flags); |
|
smp_mb__after_atomic(); |
|
|
|
schedule_pcifront_aer_op(pdev); |
|
|
|
} |
|
|
|
static irqreturn_t pcifront_handler_aer(int irq, void *dev) |
|
{ |
|
struct pcifront_device *pdev = dev; |
|
schedule_pcifront_aer_op(pdev); |
|
return IRQ_HANDLED; |
|
} |
|
static int pcifront_connect_and_init_dma(struct pcifront_device *pdev) |
|
{ |
|
int err = 0; |
|
|
|
spin_lock(&pcifront_dev_lock); |
|
|
|
if (!pcifront_dev) { |
|
dev_info(&pdev->xdev->dev, "Installing PCI frontend\n"); |
|
pcifront_dev = pdev; |
|
} else |
|
err = -EEXIST; |
|
|
|
spin_unlock(&pcifront_dev_lock); |
|
|
|
if (!err && !swiotlb_nr_tbl()) { |
|
err = pci_xen_swiotlb_init_late(); |
|
if (err) |
|
dev_err(&pdev->xdev->dev, "Could not setup SWIOTLB!\n"); |
|
} |
|
return err; |
|
} |
|
|
|
static void pcifront_disconnect(struct pcifront_device *pdev) |
|
{ |
|
spin_lock(&pcifront_dev_lock); |
|
|
|
if (pdev == pcifront_dev) { |
|
dev_info(&pdev->xdev->dev, |
|
"Disconnecting PCI Frontend Buses\n"); |
|
pcifront_dev = NULL; |
|
} |
|
|
|
spin_unlock(&pcifront_dev_lock); |
|
} |
|
static struct pcifront_device *alloc_pdev(struct xenbus_device *xdev) |
|
{ |
|
struct pcifront_device *pdev; |
|
|
|
pdev = kzalloc(sizeof(struct pcifront_device), GFP_KERNEL); |
|
if (pdev == NULL) |
|
goto out; |
|
|
|
pdev->sh_info = |
|
(struct xen_pci_sharedinfo *)__get_free_page(GFP_KERNEL); |
|
if (pdev->sh_info == NULL) { |
|
kfree(pdev); |
|
pdev = NULL; |
|
goto out; |
|
} |
|
pdev->sh_info->flags = 0; |
|
|
|
/*Flag for registering PV AER handler*/ |
|
set_bit(_XEN_PCIB_AERHANDLER, (void *)&pdev->sh_info->flags); |
|
|
|
dev_set_drvdata(&xdev->dev, pdev); |
|
pdev->xdev = xdev; |
|
|
|
INIT_LIST_HEAD(&pdev->root_buses); |
|
|
|
spin_lock_init(&pdev->sh_info_lock); |
|
|
|
pdev->evtchn = INVALID_EVTCHN; |
|
pdev->gnt_ref = INVALID_GRANT_REF; |
|
pdev->irq = -1; |
|
|
|
INIT_WORK(&pdev->op_work, pcifront_do_aer); |
|
|
|
dev_dbg(&xdev->dev, "Allocated pdev @ 0x%p pdev->sh_info @ 0x%p\n", |
|
pdev, pdev->sh_info); |
|
out: |
|
return pdev; |
|
} |
|
|
|
static void free_pdev(struct pcifront_device *pdev) |
|
{ |
|
dev_dbg(&pdev->xdev->dev, "freeing pdev @ 0x%p\n", pdev); |
|
|
|
pcifront_free_roots(pdev); |
|
|
|
cancel_work_sync(&pdev->op_work); |
|
|
|
if (pdev->irq >= 0) |
|
unbind_from_irqhandler(pdev->irq, pdev); |
|
|
|
if (pdev->evtchn != INVALID_EVTCHN) |
|
xenbus_free_evtchn(pdev->xdev, pdev->evtchn); |
|
|
|
if (pdev->gnt_ref != INVALID_GRANT_REF) |
|
gnttab_end_foreign_access(pdev->gnt_ref, 0 /* r/w page */, |
|
(unsigned long)pdev->sh_info); |
|
else |
|
free_page((unsigned long)pdev->sh_info); |
|
|
|
dev_set_drvdata(&pdev->xdev->dev, NULL); |
|
|
|
kfree(pdev); |
|
} |
|
|
|
static int pcifront_publish_info(struct pcifront_device *pdev) |
|
{ |
|
int err = 0; |
|
struct xenbus_transaction trans; |
|
grant_ref_t gref; |
|
|
|
err = xenbus_grant_ring(pdev->xdev, pdev->sh_info, 1, &gref); |
|
if (err < 0) |
|
goto out; |
|
|
|
pdev->gnt_ref = gref; |
|
|
|
err = xenbus_alloc_evtchn(pdev->xdev, &pdev->evtchn); |
|
if (err) |
|
goto out; |
|
|
|
err = bind_evtchn_to_irqhandler(pdev->evtchn, pcifront_handler_aer, |
|
0, "pcifront", pdev); |
|
|
|
if (err < 0) |
|
return err; |
|
|
|
pdev->irq = err; |
|
|
|
do_publish: |
|
err = xenbus_transaction_start(&trans); |
|
if (err) { |
|
xenbus_dev_fatal(pdev->xdev, err, |
|
"Error writing configuration for backend " |
|
"(start transaction)"); |
|
goto out; |
|
} |
|
|
|
err = xenbus_printf(trans, pdev->xdev->nodename, |
|
"pci-op-ref", "%u", pdev->gnt_ref); |
|
if (!err) |
|
err = xenbus_printf(trans, pdev->xdev->nodename, |
|
"event-channel", "%u", pdev->evtchn); |
|
if (!err) |
|
err = xenbus_printf(trans, pdev->xdev->nodename, |
|
"magic", XEN_PCI_MAGIC); |
|
|
|
if (err) { |
|
xenbus_transaction_end(trans, 1); |
|
xenbus_dev_fatal(pdev->xdev, err, |
|
"Error writing configuration for backend"); |
|
goto out; |
|
} else { |
|
err = xenbus_transaction_end(trans, 0); |
|
if (err == -EAGAIN) |
|
goto do_publish; |
|
else if (err) { |
|
xenbus_dev_fatal(pdev->xdev, err, |
|
"Error completing transaction " |
|
"for backend"); |
|
goto out; |
|
} |
|
} |
|
|
|
xenbus_switch_state(pdev->xdev, XenbusStateInitialised); |
|
|
|
dev_dbg(&pdev->xdev->dev, "publishing successful!\n"); |
|
|
|
out: |
|
return err; |
|
} |
|
|
|
static int pcifront_try_connect(struct pcifront_device *pdev) |
|
{ |
|
int err = -EFAULT; |
|
int i, num_roots, len; |
|
char str[64]; |
|
unsigned int domain, bus; |
|
|
|
|
|
/* Only connect once */ |
|
if (xenbus_read_driver_state(pdev->xdev->nodename) != |
|
XenbusStateInitialised) |
|
goto out; |
|
|
|
err = pcifront_connect_and_init_dma(pdev); |
|
if (err && err != -EEXIST) { |
|
xenbus_dev_fatal(pdev->xdev, err, |
|
"Error setting up PCI Frontend"); |
|
goto out; |
|
} |
|
|
|
err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, |
|
"root_num", "%d", &num_roots); |
|
if (err == -ENOENT) { |
|
xenbus_dev_error(pdev->xdev, err, |
|
"No PCI Roots found, trying 0000:00"); |
|
err = pcifront_scan_root(pdev, 0, 0); |
|
if (err) { |
|
xenbus_dev_fatal(pdev->xdev, err, |
|
"Error scanning PCI root 0000:00"); |
|
goto out; |
|
} |
|
num_roots = 0; |
|
} else if (err != 1) { |
|
if (err == 0) |
|
err = -EINVAL; |
|
xenbus_dev_fatal(pdev->xdev, err, |
|
"Error reading number of PCI roots"); |
|
goto out; |
|
} |
|
|
|
for (i = 0; i < num_roots; i++) { |
|
len = snprintf(str, sizeof(str), "root-%d", i); |
|
if (unlikely(len >= (sizeof(str) - 1))) { |
|
err = -ENOMEM; |
|
goto out; |
|
} |
|
|
|
err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str, |
|
"%x:%x", &domain, &bus); |
|
if (err != 2) { |
|
if (err >= 0) |
|
err = -EINVAL; |
|
xenbus_dev_fatal(pdev->xdev, err, |
|
"Error reading PCI root %d", i); |
|
goto out; |
|
} |
|
|
|
err = pcifront_scan_root(pdev, domain, bus); |
|
if (err) { |
|
xenbus_dev_fatal(pdev->xdev, err, |
|
"Error scanning PCI root %04x:%02x", |
|
domain, bus); |
|
goto out; |
|
} |
|
} |
|
|
|
err = xenbus_switch_state(pdev->xdev, XenbusStateConnected); |
|
|
|
out: |
|
return err; |
|
} |
|
|
|
static int pcifront_try_disconnect(struct pcifront_device *pdev) |
|
{ |
|
int err = 0; |
|
enum xenbus_state prev_state; |
|
|
|
|
|
prev_state = xenbus_read_driver_state(pdev->xdev->nodename); |
|
|
|
if (prev_state >= XenbusStateClosing) |
|
goto out; |
|
|
|
if (prev_state == XenbusStateConnected) { |
|
pcifront_free_roots(pdev); |
|
pcifront_disconnect(pdev); |
|
} |
|
|
|
err = xenbus_switch_state(pdev->xdev, XenbusStateClosed); |
|
|
|
out: |
|
|
|
return err; |
|
} |
|
|
|
static int pcifront_attach_devices(struct pcifront_device *pdev) |
|
{ |
|
int err = -EFAULT; |
|
int i, num_roots, len; |
|
unsigned int domain, bus; |
|
char str[64]; |
|
|
|
if (xenbus_read_driver_state(pdev->xdev->nodename) != |
|
XenbusStateReconfiguring) |
|
goto out; |
|
|
|
err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, |
|
"root_num", "%d", &num_roots); |
|
if (err == -ENOENT) { |
|
xenbus_dev_error(pdev->xdev, err, |
|
"No PCI Roots found, trying 0000:00"); |
|
err = pcifront_rescan_root(pdev, 0, 0); |
|
if (err) { |
|
xenbus_dev_fatal(pdev->xdev, err, |
|
"Error scanning PCI root 0000:00"); |
|
goto out; |
|
} |
|
num_roots = 0; |
|
} else if (err != 1) { |
|
if (err == 0) |
|
err = -EINVAL; |
|
xenbus_dev_fatal(pdev->xdev, err, |
|
"Error reading number of PCI roots"); |
|
goto out; |
|
} |
|
|
|
for (i = 0; i < num_roots; i++) { |
|
len = snprintf(str, sizeof(str), "root-%d", i); |
|
if (unlikely(len >= (sizeof(str) - 1))) { |
|
err = -ENOMEM; |
|
goto out; |
|
} |
|
|
|
err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str, |
|
"%x:%x", &domain, &bus); |
|
if (err != 2) { |
|
if (err >= 0) |
|
err = -EINVAL; |
|
xenbus_dev_fatal(pdev->xdev, err, |
|
"Error reading PCI root %d", i); |
|
goto out; |
|
} |
|
|
|
err = pcifront_rescan_root(pdev, domain, bus); |
|
if (err) { |
|
xenbus_dev_fatal(pdev->xdev, err, |
|
"Error scanning PCI root %04x:%02x", |
|
domain, bus); |
|
goto out; |
|
} |
|
} |
|
|
|
xenbus_switch_state(pdev->xdev, XenbusStateConnected); |
|
|
|
out: |
|
return err; |
|
} |
|
|
|
static int pcifront_detach_devices(struct pcifront_device *pdev) |
|
{ |
|
int err = 0; |
|
int i, num_devs; |
|
unsigned int domain, bus, slot, func; |
|
struct pci_dev *pci_dev; |
|
char str[64]; |
|
|
|
if (xenbus_read_driver_state(pdev->xdev->nodename) != |
|
XenbusStateConnected) |
|
goto out; |
|
|
|
err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, "num_devs", "%d", |
|
&num_devs); |
|
if (err != 1) { |
|
if (err >= 0) |
|
err = -EINVAL; |
|
xenbus_dev_fatal(pdev->xdev, err, |
|
"Error reading number of PCI devices"); |
|
goto out; |
|
} |
|
|
|
/* Find devices being detached and remove them. */ |
|
for (i = 0; i < num_devs; i++) { |
|
int l, state; |
|
l = snprintf(str, sizeof(str), "state-%d", i); |
|
if (unlikely(l >= (sizeof(str) - 1))) { |
|
err = -ENOMEM; |
|
goto out; |
|
} |
|
state = xenbus_read_unsigned(pdev->xdev->otherend, str, |
|
XenbusStateUnknown); |
|
|
|
if (state != XenbusStateClosing) |
|
continue; |
|
|
|
/* Remove device. */ |
|
l = snprintf(str, sizeof(str), "vdev-%d", i); |
|
if (unlikely(l >= (sizeof(str) - 1))) { |
|
err = -ENOMEM; |
|
goto out; |
|
} |
|
err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str, |
|
"%x:%x:%x.%x", &domain, &bus, &slot, &func); |
|
if (err != 4) { |
|
if (err >= 0) |
|
err = -EINVAL; |
|
xenbus_dev_fatal(pdev->xdev, err, |
|
"Error reading PCI device %d", i); |
|
goto out; |
|
} |
|
|
|
pci_dev = pci_get_domain_bus_and_slot(domain, bus, |
|
PCI_DEVFN(slot, func)); |
|
if (!pci_dev) { |
|
dev_dbg(&pdev->xdev->dev, |
|
"Cannot get PCI device %04x:%02x:%02x.%d\n", |
|
domain, bus, slot, func); |
|
continue; |
|
} |
|
pci_lock_rescan_remove(); |
|
pci_stop_and_remove_bus_device(pci_dev); |
|
pci_dev_put(pci_dev); |
|
pci_unlock_rescan_remove(); |
|
|
|
dev_dbg(&pdev->xdev->dev, |
|
"PCI device %04x:%02x:%02x.%d removed.\n", |
|
domain, bus, slot, func); |
|
} |
|
|
|
err = xenbus_switch_state(pdev->xdev, XenbusStateReconfiguring); |
|
|
|
out: |
|
return err; |
|
} |
|
|
|
static void __ref pcifront_backend_changed(struct xenbus_device *xdev, |
|
enum xenbus_state be_state) |
|
{ |
|
struct pcifront_device *pdev = dev_get_drvdata(&xdev->dev); |
|
|
|
switch (be_state) { |
|
case XenbusStateUnknown: |
|
case XenbusStateInitialising: |
|
case XenbusStateInitWait: |
|
case XenbusStateInitialised: |
|
break; |
|
|
|
case XenbusStateConnected: |
|
pcifront_try_connect(pdev); |
|
break; |
|
|
|
case XenbusStateClosed: |
|
if (xdev->state == XenbusStateClosed) |
|
break; |
|
fallthrough; /* Missed the backend's CLOSING state */ |
|
case XenbusStateClosing: |
|
dev_warn(&xdev->dev, "backend going away!\n"); |
|
pcifront_try_disconnect(pdev); |
|
break; |
|
|
|
case XenbusStateReconfiguring: |
|
pcifront_detach_devices(pdev); |
|
break; |
|
|
|
case XenbusStateReconfigured: |
|
pcifront_attach_devices(pdev); |
|
break; |
|
} |
|
} |
|
|
|
static int pcifront_xenbus_probe(struct xenbus_device *xdev, |
|
const struct xenbus_device_id *id) |
|
{ |
|
int err = 0; |
|
struct pcifront_device *pdev = alloc_pdev(xdev); |
|
|
|
if (pdev == NULL) { |
|
err = -ENOMEM; |
|
xenbus_dev_fatal(xdev, err, |
|
"Error allocating pcifront_device struct"); |
|
goto out; |
|
} |
|
|
|
err = pcifront_publish_info(pdev); |
|
if (err) |
|
free_pdev(pdev); |
|
|
|
out: |
|
return err; |
|
} |
|
|
|
static int pcifront_xenbus_remove(struct xenbus_device *xdev) |
|
{ |
|
struct pcifront_device *pdev = dev_get_drvdata(&xdev->dev); |
|
if (pdev) |
|
free_pdev(pdev); |
|
|
|
return 0; |
|
} |
|
|
|
static const struct xenbus_device_id xenpci_ids[] = { |
|
{"pci"}, |
|
{""}, |
|
}; |
|
|
|
static struct xenbus_driver xenpci_driver = { |
|
.name = "pcifront", |
|
.ids = xenpci_ids, |
|
.probe = pcifront_xenbus_probe, |
|
.remove = pcifront_xenbus_remove, |
|
.otherend_changed = pcifront_backend_changed, |
|
}; |
|
|
|
static int __init pcifront_init(void) |
|
{ |
|
if (!xen_pv_domain() || xen_initial_domain()) |
|
return -ENODEV; |
|
|
|
if (!xen_has_pv_devices()) |
|
return -ENODEV; |
|
|
|
pci_frontend_registrar(1 /* enable */); |
|
|
|
return xenbus_register_frontend(&xenpci_driver); |
|
} |
|
|
|
static void __exit pcifront_cleanup(void) |
|
{ |
|
xenbus_unregister_driver(&xenpci_driver); |
|
pci_frontend_registrar(0 /* disable */); |
|
} |
|
module_init(pcifront_init); |
|
module_exit(pcifront_cleanup); |
|
|
|
MODULE_DESCRIPTION("Xen PCI passthrough frontend."); |
|
MODULE_LICENSE("GPL"); |
|
MODULE_ALIAS("xen:pci");
|
|
|