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path: root/drivers/xen/xen-pciback/pci_stub.c
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Diffstat (limited to 'drivers/xen/xen-pciback/pci_stub.c')
-rw-r--r--drivers/xen/xen-pciback/pci_stub.c1285
1 files changed, 1285 insertions, 0 deletions
diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c
new file mode 100644
index 000000000000..0b5a16b81c8c
--- /dev/null
+++ b/drivers/xen/xen-pciback/pci_stub.c
@@ -0,0 +1,1285 @@
+/*
+ * PCI Stub Driver - Grabs devices in backend to be exported later
+ *
+ * Ryan Wilson <hap9@epoch.ncsc.mil>
+ * Chris Bookholt <hap10@epoch.ncsc.mil>
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/rwsem.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <linux/kref.h>
+#include <linux/pci.h>
+#include <linux/wait.h>
+#include <linux/sched.h>
+#include <asm/atomic.h>
+#include <xen/events.h>
+#include <asm/xen/pci.h>
+#include <asm/xen/hypervisor.h>
+#include "pciback.h"
+#include "conf_space.h"
+#include "conf_space_quirks.h"
+
+static char *pci_devs_to_hide;
+wait_queue_head_t aer_wait_queue;
+/*Add sem for sync AER handling and pciback remove/reconfigue ops,
+* We want to avoid in middle of AER ops, pciback devices is being removed
+*/
+static DECLARE_RWSEM(pcistub_sem);
+module_param_named(hide, pci_devs_to_hide, charp, 0444);
+
+struct pcistub_device_id {
+ struct list_head slot_list;
+ int domain;
+ unsigned char bus;
+ unsigned int devfn;
+};
+static LIST_HEAD(pcistub_device_ids);
+static DEFINE_SPINLOCK(device_ids_lock);
+
+struct pcistub_device {
+ struct kref kref;
+ struct list_head dev_list;
+ spinlock_t lock;
+
+ struct pci_dev *dev;
+ struct pciback_device *pdev;/* non-NULL if struct pci_dev is in use */
+};
+
+/* Access to pcistub_devices & seized_devices lists and the initialize_devices
+ * flag must be locked with pcistub_devices_lock
+ */
+static DEFINE_SPINLOCK(pcistub_devices_lock);
+static LIST_HEAD(pcistub_devices);
+
+/* wait for device_initcall before initializing our devices
+ * (see pcistub_init_devices_late)
+ */
+static int initialize_devices;
+static LIST_HEAD(seized_devices);
+
+static struct pcistub_device *pcistub_device_alloc(struct pci_dev *dev)
+{
+ struct pcistub_device *psdev;
+
+ dev_dbg(&dev->dev, "pcistub_device_alloc\n");
+
+ psdev = kzalloc(sizeof(*psdev), GFP_ATOMIC);
+ if (!psdev)
+ return NULL;
+
+ psdev->dev = pci_dev_get(dev);
+ if (!psdev->dev) {
+ kfree(psdev);
+ return NULL;
+ }
+
+ kref_init(&psdev->kref);
+ spin_lock_init(&psdev->lock);
+
+ return psdev;
+}
+
+/* Don't call this directly as it's called by pcistub_device_put */
+static void pcistub_device_release(struct kref *kref)
+{
+ struct pcistub_device *psdev;
+
+ psdev = container_of(kref, struct pcistub_device, kref);
+
+ dev_dbg(&psdev->dev->dev, "pcistub_device_release\n");
+
+ /* Clean-up the device */
+ pciback_reset_device(psdev->dev);
+ pciback_config_free_dyn_fields(psdev->dev);
+ pciback_config_free_dev(psdev->dev);
+ kfree(pci_get_drvdata(psdev->dev));
+ pci_set_drvdata(psdev->dev, NULL);
+
+ pci_dev_put(psdev->dev);
+
+ kfree(psdev);
+}
+
+static inline void pcistub_device_get(struct pcistub_device *psdev)
+{
+ kref_get(&psdev->kref);
+}
+
+static inline void pcistub_device_put(struct pcistub_device *psdev)
+{
+ kref_put(&psdev->kref, pcistub_device_release);
+}
+
+static struct pcistub_device *pcistub_device_find(int domain, int bus,
+ int slot, int func)
+{
+ struct pcistub_device *psdev = NULL;
+ unsigned long flags;
+
+ spin_lock_irqsave(&pcistub_devices_lock, flags);
+
+ list_for_each_entry(psdev, &pcistub_devices, dev_list) {
+ if (psdev->dev != NULL
+ && domain == pci_domain_nr(psdev->dev->bus)
+ && bus == psdev->dev->bus->number
+ && PCI_DEVFN(slot, func) == psdev->dev->devfn) {
+ pcistub_device_get(psdev);
+ goto out;
+ }
+ }
+
+ /* didn't find it */
+ psdev = NULL;
+
+out:
+ spin_unlock_irqrestore(&pcistub_devices_lock, flags);
+ return psdev;
+}
+
+static struct pci_dev *pcistub_device_get_pci_dev(struct pciback_device *pdev,
+ struct pcistub_device *psdev)
+{
+ struct pci_dev *pci_dev = NULL;
+ unsigned long flags;
+
+ pcistub_device_get(psdev);
+
+ spin_lock_irqsave(&psdev->lock, flags);
+ if (!psdev->pdev) {
+ psdev->pdev = pdev;
+ pci_dev = psdev->dev;
+ }
+ spin_unlock_irqrestore(&psdev->lock, flags);
+
+ if (!pci_dev)
+ pcistub_device_put(psdev);
+
+ return pci_dev;
+}
+
+struct pci_dev *pcistub_get_pci_dev_by_slot(struct pciback_device *pdev,
+ int domain, int bus,
+ int slot, int func)
+{
+ struct pcistub_device *psdev;
+ struct pci_dev *found_dev = NULL;
+ unsigned long flags;
+
+ spin_lock_irqsave(&pcistub_devices_lock, flags);
+
+ list_for_each_entry(psdev, &pcistub_devices, dev_list) {
+ if (psdev->dev != NULL
+ && domain == pci_domain_nr(psdev->dev->bus)
+ && bus == psdev->dev->bus->number
+ && PCI_DEVFN(slot, func) == psdev->dev->devfn) {
+ found_dev = pcistub_device_get_pci_dev(pdev, psdev);
+ break;
+ }
+ }
+
+ spin_unlock_irqrestore(&pcistub_devices_lock, flags);
+ return found_dev;
+}
+
+struct pci_dev *pcistub_get_pci_dev(struct pciback_device *pdev,
+ struct pci_dev *dev)
+{
+ struct pcistub_device *psdev;
+ struct pci_dev *found_dev = NULL;
+ unsigned long flags;
+
+ spin_lock_irqsave(&pcistub_devices_lock, flags);
+
+ list_for_each_entry(psdev, &pcistub_devices, dev_list) {
+ if (psdev->dev == dev) {
+ found_dev = pcistub_device_get_pci_dev(pdev, psdev);
+ break;
+ }
+ }
+
+ spin_unlock_irqrestore(&pcistub_devices_lock, flags);
+ return found_dev;
+}
+
+void pcistub_put_pci_dev(struct pci_dev *dev)
+{
+ struct pcistub_device *psdev, *found_psdev = NULL;
+ unsigned long flags;
+
+ spin_lock_irqsave(&pcistub_devices_lock, flags);
+
+ list_for_each_entry(psdev, &pcistub_devices, dev_list) {
+ if (psdev->dev == dev) {
+ found_psdev = psdev;
+ break;
+ }
+ }
+
+ spin_unlock_irqrestore(&pcistub_devices_lock, flags);
+
+ /*hold this lock for avoiding breaking link between
+ * pcistub and pciback when AER is in processing
+ */
+ down_write(&pcistub_sem);
+ /* Cleanup our device
+ * (so it's ready for the next domain)
+ */
+ pciback_reset_device(found_psdev->dev);
+ pciback_config_free_dyn_fields(found_psdev->dev);
+ pciback_config_reset_dev(found_psdev->dev);
+
+ spin_lock_irqsave(&found_psdev->lock, flags);
+ found_psdev->pdev = NULL;
+ spin_unlock_irqrestore(&found_psdev->lock, flags);
+
+ pcistub_device_put(found_psdev);
+ up_write(&pcistub_sem);
+}
+
+static int __devinit pcistub_match_one(struct pci_dev *dev,
+ struct pcistub_device_id *pdev_id)
+{
+ /* Match the specified device by domain, bus, slot, func and also if
+ * any of the device's parent bridges match.
+ */
+ for (; dev != NULL; dev = dev->bus->self) {
+ if (pci_domain_nr(dev->bus) == pdev_id->domain
+ && dev->bus->number == pdev_id->bus
+ && dev->devfn == pdev_id->devfn)
+ return 1;
+
+ /* Sometimes topmost bridge links to itself. */
+ if (dev == dev->bus->self)
+ break;
+ }
+
+ return 0;
+}
+
+static int __devinit pcistub_match(struct pci_dev *dev)
+{
+ struct pcistub_device_id *pdev_id;
+ unsigned long flags;
+ int found = 0;
+
+ spin_lock_irqsave(&device_ids_lock, flags);
+ list_for_each_entry(pdev_id, &pcistub_device_ids, slot_list) {
+ if (pcistub_match_one(dev, pdev_id)) {
+ found = 1;
+ break;
+ }
+ }
+ spin_unlock_irqrestore(&device_ids_lock, flags);
+
+ return found;
+}
+
+static int __devinit pcistub_init_device(struct pci_dev *dev)
+{
+ struct pciback_dev_data *dev_data;
+ int err = 0;
+
+ dev_dbg(&dev->dev, "initializing...\n");
+
+ /* The PCI backend is not intended to be a module (or to work with
+ * removable PCI devices (yet). If it were, pciback_config_free()
+ * would need to be called somewhere to free the memory allocated
+ * here and then to call kfree(pci_get_drvdata(psdev->dev)).
+ */
+ dev_data = kzalloc(sizeof(*dev_data), GFP_ATOMIC);
+ if (!dev_data) {
+ err = -ENOMEM;
+ goto out;
+ }
+ pci_set_drvdata(dev, dev_data);
+
+ dev_dbg(&dev->dev, "initializing config\n");
+
+ init_waitqueue_head(&aer_wait_queue);
+ err = pciback_config_init_dev(dev);
+ if (err)
+ goto out;
+
+ /* HACK: Force device (& ACPI) to determine what IRQ it's on - we
+ * must do this here because pcibios_enable_device may specify
+ * the pci device's true irq (and possibly its other resources)
+ * if they differ from what's in the configuration space.
+ * This makes the assumption that the device's resources won't
+ * change after this point (otherwise this code may break!)
+ */
+ dev_dbg(&dev->dev, "enabling device\n");
+ err = pci_enable_device(dev);
+ if (err)
+ goto config_release;
+
+ /* Now disable the device (this also ensures some private device
+ * data is setup before we export)
+ */
+ dev_dbg(&dev->dev, "reset device\n");
+ pciback_reset_device(dev);
+
+ return 0;
+
+config_release:
+ pciback_config_free_dev(dev);
+
+out:
+ pci_set_drvdata(dev, NULL);
+ kfree(dev_data);
+ return err;
+}
+
+/*
+ * Because some initialization still happens on
+ * devices during fs_initcall, we need to defer
+ * full initialization of our devices until
+ * device_initcall.
+ */
+static int __init pcistub_init_devices_late(void)
+{
+ struct pcistub_device *psdev;
+ unsigned long flags;
+ int err = 0;
+
+ pr_debug("pciback: pcistub_init_devices_late\n");
+
+ spin_lock_irqsave(&pcistub_devices_lock, flags);
+
+ while (!list_empty(&seized_devices)) {
+ psdev = container_of(seized_devices.next,
+ struct pcistub_device, dev_list);
+ list_del(&psdev->dev_list);
+
+ spin_unlock_irqrestore(&pcistub_devices_lock, flags);
+
+ err = pcistub_init_device(psdev->dev);
+ if (err) {
+ dev_err(&psdev->dev->dev,
+ "error %d initializing device\n", err);
+ kfree(psdev);
+ psdev = NULL;
+ }
+
+ spin_lock_irqsave(&pcistub_devices_lock, flags);
+
+ if (psdev)
+ list_add_tail(&psdev->dev_list, &pcistub_devices);
+ }
+
+ initialize_devices = 1;
+
+ spin_unlock_irqrestore(&pcistub_devices_lock, flags);
+
+ return 0;
+}
+
+static int __devinit pcistub_seize(struct pci_dev *dev)
+{
+ struct pcistub_device *psdev;
+ unsigned long flags;
+ int err = 0;
+
+ psdev = pcistub_device_alloc(dev);
+ if (!psdev)
+ return -ENOMEM;
+
+ spin_lock_irqsave(&pcistub_devices_lock, flags);
+
+ if (initialize_devices) {
+ spin_unlock_irqrestore(&pcistub_devices_lock, flags);
+
+ /* don't want irqs disabled when calling pcistub_init_device */
+ err = pcistub_init_device(psdev->dev);
+
+ spin_lock_irqsave(&pcistub_devices_lock, flags);
+
+ if (!err)
+ list_add(&psdev->dev_list, &pcistub_devices);
+ } else {
+ dev_dbg(&dev->dev, "deferring initialization\n");
+ list_add(&psdev->dev_list, &seized_devices);
+ }
+
+ spin_unlock_irqrestore(&pcistub_devices_lock, flags);
+
+ if (err)
+ pcistub_device_put(psdev);
+
+ return err;
+}
+
+static int __devinit pcistub_probe(struct pci_dev *dev,
+ const struct pci_device_id *id)
+{
+ int err = 0;
+
+ dev_dbg(&dev->dev, "probing...\n");
+
+ if (pcistub_match(dev)) {
+
+ if (dev->hdr_type != PCI_HEADER_TYPE_NORMAL
+ && dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
+ dev_err(&dev->dev, "can't export pci devices that "
+ "don't have a normal (0) or bridge (1) "
+ "header type!\n");
+ err = -ENODEV;
+ goto out;
+ }
+
+ dev_info(&dev->dev, "seizing device\n");
+ err = pcistub_seize(dev);
+ } else
+ /* Didn't find the device */
+ err = -ENODEV;
+
+out:
+ return err;
+}
+
+static void pcistub_remove(struct pci_dev *dev)
+{
+ struct pcistub_device *psdev, *found_psdev = NULL;
+ unsigned long flags;
+
+ dev_dbg(&dev->dev, "removing\n");
+
+ spin_lock_irqsave(&pcistub_devices_lock, flags);
+
+ pciback_config_quirk_release(dev);
+
+ list_for_each_entry(psdev, &pcistub_devices, dev_list) {
+ if (psdev->dev == dev) {
+ found_psdev = psdev;
+ break;
+ }
+ }
+
+ spin_unlock_irqrestore(&pcistub_devices_lock, flags);
+
+ if (found_psdev) {
+ dev_dbg(&dev->dev, "found device to remove - in use? %p\n",
+ found_psdev->pdev);
+
+ if (found_psdev->pdev) {
+ printk(KERN_WARNING "pciback: ****** removing device "
+ "%s while still in-use! ******\n",
+ pci_name(found_psdev->dev));
+ printk(KERN_WARNING "pciback: ****** driver domain may "
+ "still access this device's i/o resources!\n");
+ printk(KERN_WARNING "pciback: ****** shutdown driver "
+ "domain before binding device\n");
+ printk(KERN_WARNING "pciback: ****** to other drivers "
+ "or domains\n");
+
+ pciback_release_pci_dev(found_psdev->pdev,
+ found_psdev->dev);
+ }
+
+ spin_lock_irqsave(&pcistub_devices_lock, flags);
+ list_del(&found_psdev->dev_list);
+ spin_unlock_irqrestore(&pcistub_devices_lock, flags);
+
+ /* the final put for releasing from the list */
+ pcistub_device_put(found_psdev);
+ }
+}
+
+static const struct pci_device_id pcistub_ids[] = {
+ {
+ .vendor = PCI_ANY_ID,
+ .device = PCI_ANY_ID,
+ .subvendor = PCI_ANY_ID,
+ .subdevice = PCI_ANY_ID,
+ },
+ {0,},
+};
+
+#define PCI_NODENAME_MAX 40
+static void kill_domain_by_device(struct pcistub_device *psdev)
+{
+ struct xenbus_transaction xbt;
+ int err;
+ char nodename[PCI_NODENAME_MAX];
+
+ if (!psdev)
+ dev_err(&psdev->dev->dev,
+ "device is NULL when do AER recovery/kill_domain\n");
+ snprintf(nodename, PCI_NODENAME_MAX, "/local/domain/0/backend/pci/%d/0",
+ psdev->pdev->xdev->otherend_id);
+ nodename[strlen(nodename)] = '\0';
+
+again:
+ err = xenbus_transaction_start(&xbt);
+ if (err) {
+ dev_err(&psdev->dev->dev,
+ "error %d when start xenbus transaction\n", err);
+ return;
+ }
+ /*PV AER handlers will set this flag*/
+ xenbus_printf(xbt, nodename, "aerState" , "aerfail");
+ err = xenbus_transaction_end(xbt, 0);
+ if (err) {
+ if (err == -EAGAIN)
+ goto again;
+ dev_err(&psdev->dev->dev,
+ "error %d when end xenbus transaction\n", err);
+ return;
+ }
+}
+
+/* For each aer recovery step error_detected, mmio_enabled, etc, front_end and
+ * backend need to have cooperation. In pciback, those steps will do similar
+ * jobs: send service request and waiting for front_end response.
+*/
+static pci_ers_result_t common_process(struct pcistub_device *psdev,
+ pci_channel_state_t state, int aer_cmd, pci_ers_result_t result)
+{
+ pci_ers_result_t res = result;
+ struct xen_pcie_aer_op *aer_op;
+ int ret;
+
+ /*with PV AER drivers*/
+ aer_op = &(psdev->pdev->sh_info->aer_op);
+ aer_op->cmd = aer_cmd ;
+ /*useful for error_detected callback*/
+ aer_op->err = state;
+ /*pcifront_end BDF*/
+ ret = pciback_get_pcifront_dev(psdev->dev, psdev->pdev,
+ &aer_op->domain, &aer_op->bus, &aer_op->devfn);
+ if (!ret) {
+ dev_err(&psdev->dev->dev,
+ "pciback: failed to get pcifront device\n");
+ return PCI_ERS_RESULT_NONE;
+ }
+ wmb();
+
+ dev_dbg(&psdev->dev->dev,
+ "pciback: aer_op %x dom %x bus %x devfn %x\n",
+ aer_cmd, aer_op->domain, aer_op->bus, aer_op->devfn);
+ /*local flag to mark there's aer request, pciback callback will use this
+ * flag to judge whether we need to check pci-front give aer service
+ * ack signal
+ */
+ set_bit(_PCIB_op_pending, (unsigned long *)&psdev->pdev->flags);
+
+ /*It is possible that a pcifront conf_read_write ops request invokes
+ * the callback which cause the spurious execution of wake_up.
+ * Yet it is harmless and better than a spinlock here
+ */
+ set_bit(_XEN_PCIB_active,
+ (unsigned long *)&psdev->pdev->sh_info->flags);
+ wmb();
+ notify_remote_via_irq(psdev->pdev->evtchn_irq);
+
+ ret = wait_event_timeout(aer_wait_queue, !(test_bit(_XEN_PCIB_active,
+ (unsigned long *)&psdev->pdev->sh_info->flags)), 300*HZ);
+
+ if (!ret) {
+ if (test_bit(_XEN_PCIB_active,
+ (unsigned long *)&psdev->pdev->sh_info->flags)) {
+ dev_err(&psdev->dev->dev,
+ "pcifront aer process not responding!\n");
+ clear_bit(_XEN_PCIB_active,
+ (unsigned long *)&psdev->pdev->sh_info->flags);
+ aer_op->err = PCI_ERS_RESULT_NONE;
+ return res;
+ }
+ }
+ clear_bit(_PCIB_op_pending, (unsigned long *)&psdev->pdev->flags);
+
+ if (test_bit(_XEN_PCIF_active,
+ (unsigned long *)&psdev->pdev->sh_info->flags)) {
+ dev_dbg(&psdev->dev->dev,
+ "schedule pci_conf service in pciback \n");
+ test_and_schedule_op(psdev->pdev);
+ }
+
+ res = (pci_ers_result_t)aer_op->err;
+ return res;
+}
+
+/*
+* pciback_slot_reset: it will send the slot_reset request to pcifront in case
+* of the device driver could provide this service, and then wait for pcifront
+* ack.
+* @dev: pointer to PCI devices
+* return value is used by aer_core do_recovery policy
+*/
+static pci_ers_result_t pciback_slot_reset(struct pci_dev *dev)
+{
+ struct pcistub_device *psdev;
+ pci_ers_result_t result;
+
+ result = PCI_ERS_RESULT_RECOVERED;
+ dev_dbg(&dev->dev, "pciback_slot_reset(bus:%x,devfn:%x)\n",
+ dev->bus->number, dev->devfn);
+
+ down_write(&pcistub_sem);
+ psdev = pcistub_device_find(pci_domain_nr(dev->bus),
+ dev->bus->number,
+ PCI_SLOT(dev->devfn),
+ PCI_FUNC(dev->devfn));
+
+ if (!psdev || !psdev->pdev) {
+ dev_err(&dev->dev,
+ "pciback device is not found/assigned\n");
+ goto end;
+ }
+
+ if (!psdev->pdev->sh_info) {
+ dev_err(&dev->dev, "pciback device is not connected or owned"
+ " by HVM, kill it\n");
+ kill_domain_by_device(psdev);
+ goto release;
+ }
+
+ if (!test_bit(_XEN_PCIB_AERHANDLER,
+ (unsigned long *)&psdev->pdev->sh_info->flags)) {
+ dev_err(&dev->dev,
+ "guest with no AER driver should have been killed\n");
+ goto release;
+ }
+ result = common_process(psdev, 1, XEN_PCI_OP_aer_slotreset, result);
+
+ if (result == PCI_ERS_RESULT_NONE ||
+ result == PCI_ERS_RESULT_DISCONNECT) {
+ dev_dbg(&dev->dev,
+ "No AER slot_reset service or disconnected!\n");
+ kill_domain_by_device(psdev);
+ }
+release:
+ pcistub_device_put(psdev);
+end:
+ up_write(&pcistub_sem);
+ return result;
+
+}
+
+
+/*pciback_mmio_enabled: it will send the mmio_enabled request to pcifront
+* in case of the device driver could provide this service, and then wait
+* for pcifront ack
+* @dev: pointer to PCI devices
+* return value is used by aer_core do_recovery policy
+*/
+
+static pci_ers_result_t pciback_mmio_enabled(struct pci_dev *dev)
+{
+ struct pcistub_device *psdev;
+ pci_ers_result_t result;
+
+ result = PCI_ERS_RESULT_RECOVERED;
+ dev_dbg(&dev->dev, "pciback_mmio_enabled(bus:%x,devfn:%x)\n",
+ dev->bus->number, dev->devfn);
+
+ down_write(&pcistub_sem);
+ psdev = pcistub_device_find(pci_domain_nr(dev->bus),
+ dev->bus->number,
+ PCI_SLOT(dev->devfn),
+ PCI_FUNC(dev->devfn));
+
+ if (!psdev || !psdev->pdev) {
+ dev_err(&dev->dev,
+ "pciback device is not found/assigned\n");
+ goto end;
+ }
+
+ if (!psdev->pdev->sh_info) {
+ dev_err(&dev->dev, "pciback device is not connected or owned"
+ " by HVM, kill it\n");
+ kill_domain_by_device(psdev);
+ goto release;
+ }
+
+ if (!test_bit(_XEN_PCIB_AERHANDLER,
+ (unsigned long *)&psdev->pdev->sh_info->flags)) {
+ dev_err(&dev->dev,
+ "guest with no AER driver should have been killed\n");
+ goto release;
+ }
+ result = common_process(psdev, 1, XEN_PCI_OP_aer_mmio, result);
+
+ if (result == PCI_ERS_RESULT_NONE ||
+ result == PCI_ERS_RESULT_DISCONNECT) {
+ dev_dbg(&dev->dev,
+ "No AER mmio_enabled service or disconnected!\n");
+ kill_domain_by_device(psdev);
+ }
+release:
+ pcistub_device_put(psdev);
+end:
+ up_write(&pcistub_sem);
+ return result;
+}
+
+/*pciback_error_detected: it will send the error_detected request to pcifront
+* in case of the device driver could provide this service, and then wait
+* for pcifront ack.
+* @dev: pointer to PCI devices
+* @error: the current PCI connection state
+* return value is used by aer_core do_recovery policy
+*/
+
+static pci_ers_result_t pciback_error_detected(struct pci_dev *dev,
+ pci_channel_state_t error)
+{
+ struct pcistub_device *psdev;
+ pci_ers_result_t result;
+
+ result = PCI_ERS_RESULT_CAN_RECOVER;
+ dev_dbg(&dev->dev, "pciback_error_detected(bus:%x,devfn:%x)\n",
+ dev->bus->number, dev->devfn);
+
+ down_write(&pcistub_sem);
+ psdev = pcistub_device_find(pci_domain_nr(dev->bus),
+ dev->bus->number,
+ PCI_SLOT(dev->devfn),
+ PCI_FUNC(dev->devfn));
+
+ if (!psdev || !psdev->pdev) {
+ dev_err(&dev->dev,
+ "pciback device is not found/assigned\n");
+ goto end;
+ }
+
+ if (!psdev->pdev->sh_info) {
+ dev_err(&dev->dev, "pciback device is not connected or owned"
+ " by HVM, kill it\n");
+ kill_domain_by_device(psdev);
+ goto release;
+ }
+
+ /*Guest owns the device yet no aer handler regiested, kill guest*/
+ if (!test_bit(_XEN_PCIB_AERHANDLER,
+ (unsigned long *)&psdev->pdev->sh_info->flags)) {
+ dev_dbg(&dev->dev, "guest may have no aer driver, kill it\n");
+ kill_domain_by_device(psdev);
+ goto release;
+ }
+ result = common_process(psdev, error, XEN_PCI_OP_aer_detected, result);
+
+ if (result == PCI_ERS_RESULT_NONE ||
+ result == PCI_ERS_RESULT_DISCONNECT) {
+ dev_dbg(&dev->dev,
+ "No AER error_detected service or disconnected!\n");
+ kill_domain_by_device(psdev);
+ }
+release:
+ pcistub_device_put(psdev);
+end:
+ up_write(&pcistub_sem);
+ return result;
+}
+
+/*pciback_error_resume: it will send the error_resume request to pcifront
+* in case of the device driver could provide this service, and then wait
+* for pcifront ack.
+* @dev: pointer to PCI devices
+*/
+
+static void pciback_error_resume(struct pci_dev *dev)
+{
+ struct pcistub_device *psdev;
+
+ dev_dbg(&dev->dev, "pciback_error_resume(bus:%x,devfn:%x)\n",
+ dev->bus->number, dev->devfn);
+
+ down_write(&pcistub_sem);
+ psdev = pcistub_device_find(pci_domain_nr(dev->bus),
+ dev->bus->number,
+ PCI_SLOT(dev->devfn),
+ PCI_FUNC(dev->devfn));
+
+ if (!psdev || !psdev->pdev) {
+ dev_err(&dev->dev,
+ "pciback device is not found/assigned\n");
+ goto end;
+ }
+
+ if (!psdev->pdev->sh_info) {
+ dev_err(&dev->dev, "pciback device is not connected or owned"
+ " by HVM, kill it\n");
+ kill_domain_by_device(psdev);
+ goto release;
+ }
+
+ if (!test_bit(_XEN_PCIB_AERHANDLER,
+ (unsigned long *)&psdev->pdev->sh_info->flags)) {
+ dev_err(&dev->dev,
+ "guest with no AER driver should have been killed\n");
+ kill_domain_by_device(psdev);
+ goto release;
+ }
+ common_process(psdev, 1, XEN_PCI_OP_aer_resume,
+ PCI_ERS_RESULT_RECOVERED);
+release:
+ pcistub_device_put(psdev);
+end:
+ up_write(&pcistub_sem);
+ return;
+}
+
+/*add pciback AER handling*/
+static struct pci_error_handlers pciback_error_handler = {
+ .error_detected = pciback_error_detected,
+ .mmio_enabled = pciback_mmio_enabled,
+ .slot_reset = pciback_slot_reset,
+ .resume = pciback_error_resume,
+};
+
+/*
+ * Note: There is no MODULE_DEVICE_TABLE entry here because this isn't
+ * for a normal device. I don't want it to be loaded automatically.
+ */
+
+static struct pci_driver pciback_pci_driver = {
+ .name = "pciback",
+ .id_table = pcistub_ids,
+ .probe = pcistub_probe,
+ .remove = pcistub_remove,
+ .err_handler = &pciback_error_handler,
+};
+
+static inline int str_to_slot(const char *buf, int *domain, int *bus,
+ int *slot, int *func)
+{
+ int err;
+
+ err = sscanf(buf, " %x:%x:%x.%x", domain, bus, slot, func);
+ if (err == 4)
+ return 0;
+ else if (err < 0)
+ return -EINVAL;
+
+ /* try again without domain */
+ *domain = 0;
+ err = sscanf(buf, " %x:%x.%x", bus, slot, func);
+ if (err == 3)
+ return 0;
+
+ return -EINVAL;
+}
+
+static inline int str_to_quirk(const char *buf, int *domain, int *bus, int
+ *slot, int *func, int *reg, int *size, int *mask)
+{
+ int err;
+
+ err =
+ sscanf(buf, " %04x:%02x:%02x.%1x-%08x:%1x:%08x", domain, bus, slot,
+ func, reg, size, mask);
+ if (err == 7)
+ return 0;
+ return -EINVAL;
+}
+
+static int pcistub_device_id_add(int domain, int bus, int slot, int func)
+{
+ struct pcistub_device_id *pci_dev_id;
+ unsigned long flags;
+
+ pci_dev_id = kmalloc(sizeof(*pci_dev_id), GFP_KERNEL);
+ if (!pci_dev_id)
+ return -ENOMEM;
+
+ pci_dev_id->domain = domain;
+ pci_dev_id->bus = bus;
+ pci_dev_id->devfn = PCI_DEVFN(slot, func);
+
+ pr_debug("pciback: wants to seize %04x:%02x:%02x.%01x\n",
+ domain, bus, slot, func);
+
+ spin_lock_irqsave(&device_ids_lock, flags);
+ list_add_tail(&pci_dev_id->slot_list, &pcistub_device_ids);
+ spin_unlock_irqrestore(&device_ids_lock, flags);
+
+ return 0;
+}
+
+static int pcistub_device_id_remove(int domain, int bus, int slot, int func)
+{
+ struct pcistub_device_id *pci_dev_id, *t;
+ int devfn = PCI_DEVFN(slot, func);
+ int err = -ENOENT;
+ unsigned long flags;
+
+ spin_lock_irqsave(&device_ids_lock, flags);
+ list_for_each_entry_safe(pci_dev_id, t, &pcistub_device_ids,
+ slot_list) {
+ if (pci_dev_id->domain == domain
+ && pci_dev_id->bus == bus && pci_dev_id->devfn == devfn) {
+ /* Don't break; here because it's possible the same
+ * slot could be in the list more than once
+ */
+ list_del(&pci_dev_id->slot_list);
+ kfree(pci_dev_id);
+
+ err = 0;
+
+ pr_debug("pciback: removed %04x:%02x:%02x.%01x from "
+ "seize list\n", domain, bus, slot, func);
+ }
+ }
+ spin_unlock_irqrestore(&device_ids_lock, flags);
+
+ return err;
+}
+
+static int pcistub_reg_add(int domain, int bus, int slot, int func, int reg,
+ int size, int mask)
+{
+ int err = 0;
+ struct pcistub_device *psdev;
+ struct pci_dev *dev;
+ struct config_field *field;
+
+ psdev = pcistub_device_find(domain, bus, slot, func);
+ if (!psdev || !psdev->dev) {
+ err = -ENODEV;
+ goto out;
+ }
+ dev = psdev->dev;
+
+ field = kzalloc(sizeof(*field), GFP_ATOMIC);
+ if (!field) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ field->offset = reg;
+ field->size = size;
+ field->mask = mask;
+ field->init = NULL;
+ field->reset = NULL;
+ field->release = NULL;
+ field->clean = pciback_config_field_free;
+
+ err = pciback_config_quirks_add_field(dev, field);
+ if (err)
+ kfree(field);
+out:
+ return err;
+}
+
+static ssize_t pcistub_slot_add(struct device_driver *drv, const char *buf,
+ size_t count)
+{
+ int domain, bus, slot, func;
+ int err;
+
+ err = str_to_slot(buf, &domain, &bus, &slot, &func);
+ if (err)
+ goto out;
+
+ err = pcistub_device_id_add(domain, bus, slot, func);
+
+out:
+ if (!err)
+ err = count;
+ return err;
+}
+
+DRIVER_ATTR(new_slot, S_IWUSR, NULL, pcistub_slot_add);
+
+static ssize_t pcistub_slot_remove(struct device_driver *drv, const char *buf,
+ size_t count)
+{
+ int domain, bus, slot, func;
+ int err;
+
+ err = str_to_slot(buf, &domain, &bus, &slot, &func);
+ if (err)
+ goto out;
+
+ err = pcistub_device_id_remove(domain, bus, slot, func);
+
+out:
+ if (!err)
+ err = count;
+ return err;
+}
+
+DRIVER_ATTR(remove_slot, S_IWUSR, NULL, pcistub_slot_remove);
+
+static ssize_t pcistub_slot_show(struct device_driver *drv, char *buf)
+{
+ struct pcistub_device_id *pci_dev_id;
+ size_t count = 0;
+ unsigned long flags;
+
+ spin_lock_irqsave(&device_ids_lock, flags);
+ list_for_each_entry(pci_dev_id, &pcistub_device_ids, slot_list) {
+ if (count >= PAGE_SIZE)
+ break;
+
+ count += scnprintf(buf + count, PAGE_SIZE - count,
+ "%04x:%02x:%02x.%01x\n",
+ pci_dev_id->domain, pci_dev_id->bus,
+ PCI_SLOT(pci_dev_id->devfn),
+ PCI_FUNC(pci_dev_id->devfn));
+ }
+ spin_unlock_irqrestore(&device_ids_lock, flags);
+
+ return count;
+}
+
+DRIVER_ATTR(slots, S_IRUSR, pcistub_slot_show, NULL);
+
+static ssize_t pcistub_quirk_add(struct device_driver *drv, const char *buf,
+ size_t count)
+{
+ int domain, bus, slot, func, reg, size, mask;
+ int err;
+
+ err = str_to_quirk(buf, &domain, &bus, &slot, &func, &reg, &size,
+ &mask);
+ if (err)
+ goto out;
+
+ err = pcistub_reg_add(domain, bus, slot, func, reg, size, mask);
+
+out:
+ if (!err)
+ err = count;
+ return err;
+}
+
+static ssize_t pcistub_quirk_show(struct device_driver *drv, char *buf)
+{
+ int count = 0;
+ unsigned long flags;
+ struct pciback_config_quirk *quirk;
+ struct pciback_dev_data *dev_data;
+ const struct config_field *field;
+ const struct config_field_entry *cfg_entry;
+
+ spin_lock_irqsave(&device_ids_lock, flags);
+ list_for_each_entry(quirk, &pciback_quirks, quirks_list) {
+ if (count >= PAGE_SIZE)
+ goto out;
+
+ count += scnprintf(buf + count, PAGE_SIZE - count,
+ "%02x:%02x.%01x\n\t%04x:%04x:%04x:%04x\n",
+ quirk->pdev->bus->number,
+ PCI_SLOT(quirk->pdev->devfn),
+ PCI_FUNC(quirk->pdev->devfn),
+ quirk->devid.vendor, quirk->devid.device,
+ quirk->devid.subvendor,
+ quirk->devid.subdevice);
+
+ dev_data = pci_get_drvdata(quirk->pdev);
+
+ list_for_each_entry(cfg_entry, &dev_data->config_fields, list) {
+ field = cfg_entry->field;
+ if (count >= PAGE_SIZE)
+ goto out;
+
+ count += scnprintf(buf + count, PAGE_SIZE - count,
+ "\t\t%08x:%01x:%08x\n",
+ cfg_entry->base_offset +
+ field->offset, field->size,
+ field->mask);
+ }
+ }
+
+out:
+ spin_unlock_irqrestore(&device_ids_lock, flags);
+
+ return count;
+}
+
+DRIVER_ATTR(quirks, S_IRUSR | S_IWUSR, pcistub_quirk_show, pcistub_quirk_add);
+
+static ssize_t permissive_add(struct device_driver *drv, const char *buf,
+ size_t count)
+{
+ int domain, bus, slot, func;
+ int err;
+ struct pcistub_device *psdev;
+ struct pciback_dev_data *dev_data;
+ err = str_to_slot(buf, &domain, &bus, &slot, &func);
+ if (err)
+ goto out;
+ psdev = pcistub_device_find(domain, bus, slot, func);
+ if (!psdev) {
+ err = -ENODEV;
+ goto out;
+ }
+ if (!psdev->dev) {
+ err = -ENODEV;
+ goto release;
+ }
+ dev_data = pci_get_drvdata(psdev->dev);
+ /* the driver data for a device should never be null at this point */
+ if (!dev_data) {
+ err = -ENXIO;
+ goto release;
+ }
+ if (!dev_data->permissive) {
+ dev_data->permissive = 1;
+ /* Let user know that what they're doing could be unsafe */
+ dev_warn(&psdev->dev->dev, "enabling permissive mode "
+ "configuration space accesses!\n");
+ dev_warn(&psdev->dev->dev,
+ "permissive mode is potentially unsafe!\n");
+ }
+release:
+ pcistub_device_put(psdev);
+out:
+ if (!err)
+ err = count;
+ return err;
+}
+
+static ssize_t permissive_show(struct device_driver *drv, char *buf)
+{
+ struct pcistub_device *psdev;
+ struct pciback_dev_data *dev_data;
+ size_t count = 0;
+ unsigned long flags;
+ spin_lock_irqsave(&pcistub_devices_lock, flags);
+ list_for_each_entry(psdev, &pcistub_devices, dev_list) {
+ if (count >= PAGE_SIZE)
+ break;
+ if (!psdev->dev)
+ continue;
+ dev_data = pci_get_drvdata(psdev->dev);
+ if (!dev_data || !dev_data->permissive)
+ continue;
+ count +=
+ scnprintf(buf + count, PAGE_SIZE - count, "%s\n",
+ pci_name(psdev->dev));
+ }
+ spin_unlock_irqrestore(&pcistub_devices_lock, flags);
+ return count;
+}
+
+DRIVER_ATTR(permissive, S_IRUSR | S_IWUSR, permissive_show, permissive_add);
+
+static void pcistub_exit(void)
+{
+ driver_remove_file(&pciback_pci_driver.driver, &driver_attr_new_slot);
+ driver_remove_file(&pciback_pci_driver.driver,
+ &driver_attr_remove_slot);
+ driver_remove_file(&pciback_pci_driver.driver, &driver_attr_slots);
+ driver_remove_file(&pciback_pci_driver.driver, &driver_attr_quirks);
+ driver_remove_file(&pciback_pci_driver.driver, &driver_attr_permissive);
+
+ pci_unregister_driver(&pciback_pci_driver);
+}
+
+static int __init pcistub_init(void)
+{
+ int pos = 0;
+ int err = 0;
+ int domain, bus, slot, func;
+ int parsed;
+
+ if (pci_devs_to_hide && *pci_devs_to_hide) {
+ do {
+ parsed = 0;
+
+ err = sscanf(pci_devs_to_hide + pos,
+ " (%x:%x:%x.%x) %n",
+ &domain, &bus, &slot, &func, &parsed);
+ if (err != 4) {
+ domain = 0;
+ err = sscanf(pci_devs_to_hide + pos,
+ " (%x:%x.%x) %n",
+ &bus, &slot, &func, &parsed);
+ if (err != 3)
+ goto parse_error;
+ }
+
+ err = pcistub_device_id_add(domain, bus, slot, func);
+ if (err)
+ goto out;
+
+ /* if parsed<=0, we've reached the end of the string */
+ pos += parsed;
+ } while (parsed > 0 && pci_devs_to_hide[pos]);
+ }
+
+ /* If we're the first PCI Device Driver to register, we're the
+ * first one to get offered PCI devices as they become
+ * available (and thus we can be the first to grab them)
+ */
+ err = pci_register_driver(&pciback_pci_driver);
+ if (err < 0)
+ goto out;
+
+ err = driver_create_file(&pciback_pci_driver.driver,
+ &driver_attr_new_slot);
+ if (!err)
+ err = driver_create_file(&pciback_pci_driver.driver,
+ &driver_attr_remove_slot);
+ if (!err)
+ err = driver_create_file(&pciback_pci_driver.driver,
+ &driver_attr_slots);
+ if (!err)
+ err = driver_create_file(&pciback_pci_driver.driver,
+ &driver_attr_quirks);
+ if (!err)
+ err = driver_create_file(&pciback_pci_driver.driver,
+ &driver_attr_permissive);
+
+ if (err)
+ pcistub_exit();
+
+out:
+ return err;
+
+parse_error:
+ printk(KERN_ERR "pciback: Error parsing pci_devs_to_hide at \"%s\"\n",
+ pci_devs_to_hide + pos);
+ return -EINVAL;
+}
+
+#ifndef MODULE
+/*
+ * fs_initcall happens before device_initcall
+ * so pciback *should* get called first (b/c we
+ * want to suck up any device before other drivers
+ * get a chance by being the first pci device
+ * driver to register)
+ */
+fs_initcall(pcistub_init);
+#endif
+
+static int __init pciback_init(void)
+{
+ int err;
+
+ if (!xen_initial_domain())
+ return -ENODEV;
+
+ err = pciback_config_init();
+ if (err)
+ return err;
+
+#ifdef MODULE
+ err = pcistub_init();
+ if (err < 0)
+ return err;
+#endif
+
+ pcistub_init_devices_late();
+ err = pciback_xenbus_register();
+ if (err)
+ pcistub_exit();
+
+ return err;
+}
+
+static void __exit pciback_cleanup(void)
+{
+ pciback_xenbus_unregister();
+ pcistub_exit();
+}
+
+module_init(pciback_init);
+module_exit(pciback_cleanup);
+
+MODULE_LICENSE("Dual BSD/GPL");