[deliverable/linux.git] / drivers / xen / xen-pciback / pciback_ops.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/module.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) {
		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);

		pci_write_config_word(dev, PCI_COMMAND, 0);

		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));

	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)
{
	struct xen_pcibk_dev_data *dev_data;

	if (unlikely(verbose_request))
		printk(KERN_DEBUG DRV_NAME ": %s: disable MSI\n",
		       pci_name(dev));
	pci_disable_msi(dev);

	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 = 1;
	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;

	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;

	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)
{
	struct xen_pcibk_dev_data *dev_data;
	if (unlikely(verbose_request))
		printk(KERN_DEBUG DRV_NAME ": %s: disable MSI-X\n",
			pci_name(dev));
	pci_disable_msix(dev);

	/*
	 * 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);
	dev_data = pci_get_drvdata(dev);
	if (dev_data)
		dev_data->ack_intr = 1;
	return 0;
}
#endif
/*
* 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
*/
void xen_pcibk_test_and_schedule_op(struct xen_pcibk_device *pdev)
{
	/* Check that frontend is requesting an operation and that we are not
	 * already processing a request */
	if (test_bit(_XEN_PCIF_active, (unsigned long *)&pdev->sh_info->flags)
	    && !test_and_set_bit(_PDEVF_op_active, &pdev->flags)) {
		queue_work(xen_pcibk_wq, &pdev->op_work);
	}
	/*_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);
	}
}

/* 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 */

void xen_pcibk_do_op(struct work_struct *data)
{
	struct xen_pcibk_device *pdev =
		container_of(data, struct xen_pcibk_device, op_work);
	struct pci_dev *dev;
	struct xen_pcibk_dev_data *dev_data = NULL;
	struct xen_pci_op *op = &pdev->sh_info->op;
	int test_intx = 0;

	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:
			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 */);
	}
	/* 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_clear_bit(); /* /after/ clearing PCIF_active */
	clear_bit(_PDEVF_op_active, &pdev->flags);
	smp_mb__after_clear_bit(); /* /before/ final check for work */

	/* Check to see if the driver domain tried to start another request in
	 * between clearing _XEN_PCIF_active and clearing _PDEVF_op_active.
	*/
	xen_pcibk_test_and_schedule_op(pdev);
}

irqreturn_t xen_pcibk_handle_event(int irq, void *dev_id)
{
	struct xen_pcibk_device *pdev = dev_id;

	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;
}
Commit	Line	Data
30edc14b KRW	1	/*
	2	* PCI Backend Operations - respond to PCI requests from Frontend
	3	*
	4	* Author: Ryan Wilson <hap9@epoch.ncsc.mil>
	5	*/
283c0972 JP	6
	7	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
	8
30edc14b KRW	9	#include <linux/module.h>
	10	#include <linux/wait.h>
	11	#include <linux/bitops.h>
	12	#include <xen/events.h>
	13	#include <linux/sched.h>
	14	#include "pciback.h"
	15
	16	int verbose_request;
	17	module_param(verbose_request, int, 0644);
	18
a92336a1 KRW	19	static irqreturn_t xen_pcibk_guest_interrupt(int irq, void *dev_id);
a92336a1 KRW	20
0513fe9e	21	/* Ensure a device is has the fake IRQ handler "turned on/off" and is
a92336a1	22	* ready to be exported. This MUST be run after xen_pcibk_reset_device
0513fe9e KRW	23	* which does the actual PCI device enable/disable.
0513fe9e KRW	24	*/
a92336a1	25	static void xen_pcibk_control_isr(struct pci_dev *dev, int reset)
0513fe9e	26	{
a92336a1	27	struct xen_pcibk_dev_data *dev_data;
0513fe9e KRW	28	int rc;
	29	int enable = 0;
	30
	31	dev_data = pci_get_drvdata(dev);
	32	if (!dev_data)
	33	return;
	34
	35	/* We don't deal with bridges */
	36	if (dev->hdr_type != PCI_HEADER_TYPE_NORMAL)
	37	return;
	38
	39	if (reset) {
	40	dev_data->enable_intx = 0;
	41	dev_data->ack_intr = 0;
	42	}
	43	enable = dev_data->enable_intx;
	44
	45	/* Asked to disable, but ISR isn't runnig */
	46	if (!enable && !dev_data->isr_on)
	47	return;
	48
	49	/* Squirrel away the IRQs in the dev_data. We need this
	50	* b/c when device transitions to MSI, the dev->irq is
	51	* overwritten with the MSI vector.
	52	*/
	53	if (enable)
	54	dev_data->irq = dev->irq;
	55
e17ab35f KRW	56	/*
	57	* SR-IOV devices in all use MSI-X and have no legacy
	58	* interrupts, so inhibit creating a fake IRQ handler for them.
	59	*/
	60	if (dev_data->irq == 0)
	61	goto out;
	62
0513fe9e KRW	63	dev_dbg(&dev->dev, "%s: #%d %s %s%s %s-> %s\n",
	64	dev_data->irq_name,
	65	dev_data->irq,
	66	pci_is_enabled(dev) ? "on" : "off",
	67	dev->msi_enabled ? "MSI" : "",
	68	dev->msix_enabled ? "MSI/X" : "",
	69	dev_data->isr_on ? "enable" : "disable",
	70	enable ? "enable" : "disable");
	71
	72	if (enable) {
	73	rc = request_irq(dev_data->irq,
a92336a1	74	xen_pcibk_guest_interrupt, IRQF_SHARED,
0513fe9e KRW	75	dev_data->irq_name, dev);
	76	if (rc) {
	77	dev_err(&dev->dev, "%s: failed to install fake IRQ " \
	78	"handler for IRQ %d! (rc:%d)\n",
	79	dev_data->irq_name, dev_data->irq, rc);
	80	goto out;
	81	}
	82	} else {
	83	free_irq(dev_data->irq, dev);
	84	dev_data->irq = 0;
	85	}
	86	dev_data->isr_on = enable;
	87	dev_data->ack_intr = enable;
	88	out:
	89	dev_dbg(&dev->dev, "%s: #%d %s %s%s %s\n",
	90	dev_data->irq_name,
	91	dev_data->irq,
	92	pci_is_enabled(dev) ? "on" : "off",
	93	dev->msi_enabled ? "MSI" : "",
	94	dev->msix_enabled ? "MSI/X" : "",
	95	enable ? (dev_data->isr_on ? "enabled" : "failed to enable") :
	96	(dev_data->isr_on ? "failed to disable" : "disabled"));
	97	}
	98
30edc14b	99	/* Ensure a device is "turned off" and ready to be exported.
a92336a1	100	* (Also see xen_pcibk_config_reset to ensure virtual configuration space is
30edc14b KRW	101	* ready to be re-exported)
30edc14b KRW	102	*/
a92336a1	103	void xen_pcibk_reset_device(struct pci_dev *dev)
30edc14b KRW	104	{
	105	u16 cmd;
	106
a92336a1	107	xen_pcibk_control_isr(dev, 1 /* reset device */);
0513fe9e	108
30edc14b KRW	109	/* Disable devices (but not bridges) */
30edc14b KRW	110	if (dev->hdr_type == PCI_HEADER_TYPE_NORMAL) {
a2be65fd KRW	111	#ifdef CONFIG_PCI_MSI
	112	/* The guest could have been abruptly killed without
	113	* disabling MSI/MSI-X interrupts.*/
	114	if (dev->msix_enabled)
	115	pci_disable_msix(dev);
	116	if (dev->msi_enabled)
	117	pci_disable_msi(dev);
	118	#endif
bdc5c181 KRW	119	if (pci_is_enabled(dev))
bdc5c181 KRW	120	pci_disable_device(dev);
30edc14b KRW	121
	122	pci_write_config_word(dev, PCI_COMMAND, 0);
	123
	124	dev->is_busmaster = 0;
	125	} else {
	126	pci_read_config_word(dev, PCI_COMMAND, &cmd);
	127	if (cmd & (PCI_COMMAND_INVALIDATE)) {
	128	cmd &= ~(PCI_COMMAND_INVALIDATE);
	129	pci_write_config_word(dev, PCI_COMMAND, cmd);
	130
	131	dev->is_busmaster = 0;
	132	}
	133	}
	134	}
a92336a1 KRW	135
	136	#ifdef CONFIG_PCI_MSI
	137	static
	138	int xen_pcibk_enable_msi(struct xen_pcibk_device *pdev,
	139	struct pci_dev dev, struct xen_pci_op op)
	140	{
	141	struct xen_pcibk_dev_data *dev_data;
a92336a1 KRW	142	int status;
	143
	144	if (unlikely(verbose_request))
	145	printk(KERN_DEBUG DRV_NAME ": %s: enable MSI\n", pci_name(dev));
	146
	147	status = pci_enable_msi(dev);
	148
	149	if (status) {
283c0972	150	pr_warn_ratelimited("%s: error enabling MSI for guest %u: err %d\n",
51ac8893 JB	151	pci_name(dev), pdev->xdev->otherend_id,
51ac8893 JB	152	status);
a92336a1 KRW	153	op->value = 0;
	154	return XEN_PCI_ERR_op_failed;
	155	}
	156
	157	/* The value the guest needs is actually the IDT vector, not the
	158	* the local domain's IRQ number. */
	159
	160	op->value = dev->irq ? xen_pirq_from_irq(dev->irq) : 0;
	161	if (unlikely(verbose_request))
	162	printk(KERN_DEBUG DRV_NAME ": %s: MSI: %d\n", pci_name(dev),
	163	op->value);
	164
	165	dev_data = pci_get_drvdata(dev);
	166	if (dev_data)
	167	dev_data->ack_intr = 0;
	168
	169	return 0;
	170	}
	171
	172	static
	173	int xen_pcibk_disable_msi(struct xen_pcibk_device *pdev,
	174	struct pci_dev dev, struct xen_pci_op op)
	175	{
	176	struct xen_pcibk_dev_data *dev_data;
	177
	178	if (unlikely(verbose_request))
	179	printk(KERN_DEBUG DRV_NAME ": %s: disable MSI\n",
	180	pci_name(dev));
	181	pci_disable_msi(dev);
	182
	183	op->value = dev->irq ? xen_pirq_from_irq(dev->irq) : 0;
	184	if (unlikely(verbose_request))
	185	printk(KERN_DEBUG DRV_NAME ": %s: MSI: %d\n", pci_name(dev),
	186	op->value);
	187	dev_data = pci_get_drvdata(dev);
	188	if (dev_data)
	189	dev_data->ack_intr = 1;
	190	return 0;
	191	}
	192
	193	static
	194	int xen_pcibk_enable_msix(struct xen_pcibk_device *pdev,
	195	struct pci_dev dev, struct xen_pci_op op)
	196	{
	197	struct xen_pcibk_dev_data *dev_data;
	198	int i, result;
	199	struct msix_entry *entries;
	200
	201	if (unlikely(verbose_request))
	202	printk(KERN_DEBUG DRV_NAME ": %s: enable MSI-X\n",
	203	pci_name(dev));
	204	if (op->value > SH_INFO_MAX_VEC)
	205	return -EINVAL;
	206
	207	entries = kmalloc(op->value * sizeof(*entries), GFP_KERNEL);
	208	if (entries == NULL)
	209	return -ENOMEM;
	210
	211	for (i = 0; i < op->value; i++) {
	212	entries[i].entry = op->msix_entries[i].entry;
	213	entries[i].vector = op->msix_entries[i].vector;
	214	}
	215
efdfa3ed	216	result = pci_enable_msix_exact(dev, entries, op->value);
a92336a1 KRW	217	if (result == 0) {
	218	for (i = 0; i < op->value; i++) {
	219	op->msix_entries[i].entry = entries[i].entry;
c0914e61	220	if (entries[i].vector) {
a92336a1 KRW	221	op->msix_entries[i].vector =
	222	xen_pirq_from_irq(entries[i].vector);
	223	if (unlikely(verbose_request))
	224	printk(KERN_DEBUG DRV_NAME ": %s: " \
	225	"MSI-X[%d]: %d\n",
	226	pci_name(dev), i,
	227	op->msix_entries[i].vector);
c0914e61	228	}
a92336a1	229	}
51ac8893	230	} else
283c0972	231	pr_warn_ratelimited("%s: error enabling MSI-X for guest %u: err %d!\n",
51ac8893 JB	232	pci_name(dev), pdev->xdev->otherend_id,
51ac8893 JB	233	result);
a92336a1 KRW	234	kfree(entries);
	235
	236	op->value = result;
	237	dev_data = pci_get_drvdata(dev);
	238	if (dev_data)
	239	dev_data->ack_intr = 0;
	240
0ee46eca	241	return result > 0 ? 0 : result;
a92336a1 KRW	242	}
	243
	244	static
	245	int xen_pcibk_disable_msix(struct xen_pcibk_device *pdev,
	246	struct pci_dev dev, struct xen_pci_op op)
	247	{
	248	struct xen_pcibk_dev_data *dev_data;
	249	if (unlikely(verbose_request))
	250	printk(KERN_DEBUG DRV_NAME ": %s: disable MSI-X\n",
	251	pci_name(dev));
	252	pci_disable_msix(dev);
	253
	254	/*
	255	* SR-IOV devices (which don't have any legacy IRQ) have
	256	* an undefined IRQ value of zero.
	257	*/
	258	op->value = dev->irq ? xen_pirq_from_irq(dev->irq) : 0;
	259	if (unlikely(verbose_request))
	260	printk(KERN_DEBUG DRV_NAME ": %s: MSI-X: %d\n", pci_name(dev),
	261	op->value);
	262	dev_data = pci_get_drvdata(dev);
	263	if (dev_data)
	264	dev_data->ack_intr = 1;
	265	return 0;
	266	}
	267	#endif
30edc14b KRW	268	/*
	269	* Now the same evtchn is used for both pcifront conf_read_write request
	270	* as well as pcie aer front end ack. We use a new work_queue to schedule
a92336a1	271	* xen_pcibk conf_read_write service for avoiding confict with aer_core
30edc14b KRW	272	* do_recovery job which also use the system default work_queue
30edc14b KRW	273	*/
a92336a1	274	void xen_pcibk_test_and_schedule_op(struct xen_pcibk_device *pdev)
30edc14b KRW	275	{
	276	/* Check that frontend is requesting an operation and that we are not
	277	* already processing a request */
	278	if (test_bit(_XEN_PCIF_active, (unsigned long *)&pdev->sh_info->flags)
	279	&& !test_and_set_bit(_PDEVF_op_active, &pdev->flags)) {
a92336a1	280	queue_work(xen_pcibk_wq, &pdev->op_work);
30edc14b KRW	281	}
30edc14b KRW	282	/*_XEN_PCIB_active should have been cleared by pcifront. And also make
a92336a1	283	sure xen_pcibk is waiting for ack by checking _PCIB_op_pending*/
30edc14b KRW	284	if (!test_bit(_XEN_PCIB_active, (unsigned long *)&pdev->sh_info->flags)
30edc14b KRW	285	&& test_bit(_PCIB_op_pending, &pdev->flags)) {
a92336a1	286	wake_up(&xen_pcibk_aer_wait_queue);
30edc14b KRW	287	}
	288	}
	289
	290	/* Performing the configuration space reads/writes must not be done in atomic
	291	* context because some of the pci_* functions can sleep (mostly due to ACPI
	292	* use of semaphores). This function is intended to be called from a work
a92336a1	293	* queue in process context taking a struct xen_pcibk_device as a parameter */
30edc14b	294
a92336a1	295	void xen_pcibk_do_op(struct work_struct *data)
30edc14b	296	{
a92336a1 KRW	297	struct xen_pcibk_device *pdev =
a92336a1 KRW	298	container_of(data, struct xen_pcibk_device, op_work);
30edc14b	299	struct pci_dev *dev;
a92336a1	300	struct xen_pcibk_dev_data *dev_data = NULL;
30edc14b	301	struct xen_pci_op *op = &pdev->sh_info->op;
0513fe9e	302	int test_intx = 0;
30edc14b	303
a92336a1	304	dev = xen_pcibk_get_pci_dev(pdev, op->domain, op->bus, op->devfn);
30edc14b KRW	305
	306	if (dev == NULL)
	307	op->err = XEN_PCI_ERR_dev_not_found;
	308	else {
0513fe9e KRW	309	dev_data = pci_get_drvdata(dev);
	310	if (dev_data)
	311	test_intx = dev_data->enable_intx;
30edc14b KRW	312	switch (op->cmd) {
30edc14b KRW	313	case XEN_PCI_OP_conf_read:
a92336a1	314	op->err = xen_pcibk_config_read(dev,
30edc14b KRW	315	op->offset, op->size, &op->value);
	316	break;
	317	case XEN_PCI_OP_conf_write:
a92336a1	318	op->err = xen_pcibk_config_write(dev,
30edc14b KRW	319	op->offset, op->size, op->value);
	320	break;
	321	#ifdef CONFIG_PCI_MSI
	322	case XEN_PCI_OP_enable_msi:
a92336a1	323	op->err = xen_pcibk_enable_msi(pdev, dev, op);
30edc14b KRW	324	break;
30edc14b KRW	325	case XEN_PCI_OP_disable_msi:
a92336a1	326	op->err = xen_pcibk_disable_msi(pdev, dev, op);
30edc14b KRW	327	break;
30edc14b KRW	328	case XEN_PCI_OP_enable_msix:
a92336a1	329	op->err = xen_pcibk_enable_msix(pdev, dev, op);
30edc14b KRW	330	break;
30edc14b KRW	331	case XEN_PCI_OP_disable_msix:
a92336a1	332	op->err = xen_pcibk_disable_msix(pdev, dev, op);
30edc14b KRW	333	break;
	334	#endif
	335	default:
	336	op->err = XEN_PCI_ERR_not_implemented;
	337	break;
	338	}
	339	}
0513fe9e KRW	340	if (!op->err && dev && dev_data) {
	341	/* Transition detected */
	342	if ((dev_data->enable_intx != test_intx))
a92336a1	343	xen_pcibk_control_isr(dev, 0 /* no reset */);
0513fe9e	344	}
30edc14b KRW	345	/* Tell the driver domain that we're done. */
	346	wmb();
	347	clear_bit(_XEN_PCIF_active, (unsigned long *)&pdev->sh_info->flags);
	348	notify_remote_via_irq(pdev->evtchn_irq);
	349
	350	/* Mark that we're done. */
	351	smp_mb__before_clear_bit(); /* /after/ clearing PCIF_active */
	352	clear_bit(_PDEVF_op_active, &pdev->flags);
	353	smp_mb__after_clear_bit(); /* /before/ final check for work */
	354
	355	/* Check to see if the driver domain tried to start another request in
	356	* between clearing _XEN_PCIF_active and clearing _PDEVF_op_active.
	357	*/
a92336a1	358	xen_pcibk_test_and_schedule_op(pdev);
30edc14b KRW	359	}
30edc14b KRW	360
a92336a1	361	irqreturn_t xen_pcibk_handle_event(int irq, void *dev_id)
30edc14b	362	{
a92336a1	363	struct xen_pcibk_device *pdev = dev_id;
30edc14b	364
a92336a1	365	xen_pcibk_test_and_schedule_op(pdev);
30edc14b KRW	366
	367	return IRQ_HANDLED;
	368	}
a92336a1	369	static irqreturn_t xen_pcibk_guest_interrupt(int irq, void *dev_id)
0513fe9e KRW	370	{
0513fe9e KRW	371	struct pci_dev dev = (struct pci_dev )dev_id;
a92336a1	372	struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev);
0513fe9e KRW	373
	374	if (dev_data->isr_on && dev_data->ack_intr) {
	375	dev_data->handled++;
	376	if ((dev_data->handled % 1000) == 0) {
	377	if (xen_test_irq_shared(irq)) {
283c0972	378	pr_info("%s IRQ line is not shared "
0513fe9e KRW	379	"with other domains. Turning ISR off\n",
	380	dev_data->irq_name);
	381	dev_data->ack_intr = 0;
	382	}
	383	}
	384	return IRQ_HANDLED;
	385	}
	386	return IRQ_NONE;
	387	}