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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Virtio PCI driver - common functionality for all device versions4 *5 * This module allows virtio devices to be used over a virtual PCI device.6 * This can be used with QEMU based VMMs like KVM or Xen.7 *8 * Copyright IBM Corp. 20079 * Copyright Red Hat, Inc. 201410 *11 * Authors:12 *  Anthony Liguori  <aliguori@us.ibm.com>13 *  Rusty Russell <rusty@rustcorp.com.au>14 *  Michael S. Tsirkin <mst@redhat.com>15 */16 17#include "virtio_pci_common.h"18 19static bool force_legacy = false;20 21#if IS_ENABLED(CONFIG_VIRTIO_PCI_LEGACY)22module_param(force_legacy, bool, 0444);23MODULE_PARM_DESC(force_legacy,24		 "Force legacy mode for transitional virtio 1 devices");25#endif26 27bool vp_is_avq(struct virtio_device *vdev, unsigned int index)28{29	struct virtio_pci_device *vp_dev = to_vp_device(vdev);30 31	if (!virtio_has_feature(vdev, VIRTIO_F_ADMIN_VQ))32		return false;33 34	return index == vp_dev->admin_vq.vq_index;35}36 37/* wait for pending irq handlers */38void vp_synchronize_vectors(struct virtio_device *vdev)39{40	struct virtio_pci_device *vp_dev = to_vp_device(vdev);41	int i;42 43	if (vp_dev->intx_enabled)44		synchronize_irq(vp_dev->pci_dev->irq);45 46	for (i = 0; i < vp_dev->msix_vectors; ++i)47		synchronize_irq(pci_irq_vector(vp_dev->pci_dev, i));48}49 50/* the notify function used when creating a virt queue */51bool vp_notify(struct virtqueue *vq)52{53	/* we write the queue's selector into the notification register to54	 * signal the other end */55	iowrite16(vq->index, (void __iomem *)vq->priv);56	return true;57}58 59/* Notify all slow path virtqueues on an interrupt. */60static void vp_vring_slow_path_interrupt(int irq,61					 struct virtio_pci_device *vp_dev)62{63	struct virtio_pci_vq_info *info;64	unsigned long flags;65 66	spin_lock_irqsave(&vp_dev->lock, flags);67	list_for_each_entry(info, &vp_dev->slow_virtqueues, node)68		vring_interrupt(irq, info->vq);69	spin_unlock_irqrestore(&vp_dev->lock, flags);70}71 72/* Handle a configuration change: Tell driver if it wants to know. */73static irqreturn_t vp_config_changed(int irq, void *opaque)74{75	struct virtio_pci_device *vp_dev = opaque;76 77	virtio_config_changed(&vp_dev->vdev);78	vp_vring_slow_path_interrupt(irq, vp_dev);79	return IRQ_HANDLED;80}81 82/* Notify all virtqueues on an interrupt. */83static irqreturn_t vp_vring_interrupt(int irq, void *opaque)84{85	struct virtio_pci_device *vp_dev = opaque;86	struct virtio_pci_vq_info *info;87	irqreturn_t ret = IRQ_NONE;88	unsigned long flags;89 90	spin_lock_irqsave(&vp_dev->lock, flags);91	list_for_each_entry(info, &vp_dev->virtqueues, node) {92		if (vring_interrupt(irq, info->vq) == IRQ_HANDLED)93			ret = IRQ_HANDLED;94	}95	spin_unlock_irqrestore(&vp_dev->lock, flags);96 97	return ret;98}99 100/* A small wrapper to also acknowledge the interrupt when it's handled.101 * I really need an EIO hook for the vring so I can ack the interrupt once we102 * know that we'll be handling the IRQ but before we invoke the callback since103 * the callback may notify the host which results in the host attempting to104 * raise an interrupt that we would then mask once we acknowledged the105 * interrupt. */106static irqreturn_t vp_interrupt(int irq, void *opaque)107{108	struct virtio_pci_device *vp_dev = opaque;109	u8 isr;110 111	/* reading the ISR has the effect of also clearing it so it's very112	 * important to save off the value. */113	isr = ioread8(vp_dev->isr);114 115	/* It's definitely not us if the ISR was not high */116	if (!isr)117		return IRQ_NONE;118 119	/* Configuration change?  Tell driver if it wants to know. */120	if (isr & VIRTIO_PCI_ISR_CONFIG)121		vp_config_changed(irq, opaque);122 123	return vp_vring_interrupt(irq, opaque);124}125 126static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors,127				   bool per_vq_vectors, struct irq_affinity *desc)128{129	struct virtio_pci_device *vp_dev = to_vp_device(vdev);130	const char *name = dev_name(&vp_dev->vdev.dev);131	unsigned int flags = PCI_IRQ_MSIX;132	unsigned int i, v;133	int err = -ENOMEM;134 135	vp_dev->msix_vectors = nvectors;136 137	vp_dev->msix_names = kmalloc_array(nvectors,138					   sizeof(*vp_dev->msix_names),139					   GFP_KERNEL);140	if (!vp_dev->msix_names)141		goto error;142	vp_dev->msix_affinity_masks143		= kcalloc(nvectors, sizeof(*vp_dev->msix_affinity_masks),144			  GFP_KERNEL);145	if (!vp_dev->msix_affinity_masks)146		goto error;147	for (i = 0; i < nvectors; ++i)148		if (!alloc_cpumask_var(&vp_dev->msix_affinity_masks[i],149					GFP_KERNEL))150			goto error;151 152	if (!per_vq_vectors)153		desc = NULL;154 155	if (desc) {156		flags |= PCI_IRQ_AFFINITY;157		desc->pre_vectors++; /* virtio config vector */158	}159 160	err = pci_alloc_irq_vectors_affinity(vp_dev->pci_dev, nvectors,161					     nvectors, flags, desc);162	if (err < 0)163		goto error;164	vp_dev->msix_enabled = 1;165 166	/* Set the vector used for configuration */167	v = vp_dev->msix_used_vectors;168	snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names,169		 "%s-config", name);170	err = request_irq(pci_irq_vector(vp_dev->pci_dev, v),171			  vp_config_changed, 0, vp_dev->msix_names[v],172			  vp_dev);173	if (err)174		goto error;175	++vp_dev->msix_used_vectors;176 177	v = vp_dev->config_vector(vp_dev, v);178	/* Verify we had enough resources to assign the vector */179	if (v == VIRTIO_MSI_NO_VECTOR) {180		err = -EBUSY;181		goto error;182	}183 184	if (!per_vq_vectors) {185		/* Shared vector for all VQs */186		v = vp_dev->msix_used_vectors;187		snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names,188			 "%s-virtqueues", name);189		err = request_irq(pci_irq_vector(vp_dev->pci_dev, v),190				  vp_vring_interrupt, 0, vp_dev->msix_names[v],191				  vp_dev);192		if (err)193			goto error;194		++vp_dev->msix_used_vectors;195	}196	return 0;197error:198	return err;199}200 201static bool vp_is_slow_path_vector(u16 msix_vec)202{203	return msix_vec == VP_MSIX_CONFIG_VECTOR;204}205 206static struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned int index,207				     void (*callback)(struct virtqueue *vq),208				     const char *name,209				     bool ctx,210				     u16 msix_vec,211				     struct virtio_pci_vq_info **p_info)212{213	struct virtio_pci_device *vp_dev = to_vp_device(vdev);214	struct virtio_pci_vq_info *info = kmalloc(sizeof *info, GFP_KERNEL);215	struct virtqueue *vq;216	unsigned long flags;217 218	/* fill out our structure that represents an active queue */219	if (!info)220		return ERR_PTR(-ENOMEM);221 222	vq = vp_dev->setup_vq(vp_dev, info, index, callback, name, ctx,223			      msix_vec);224	if (IS_ERR(vq))225		goto out_info;226 227	info->vq = vq;228	if (callback) {229		spin_lock_irqsave(&vp_dev->lock, flags);230		if (!vp_is_slow_path_vector(msix_vec))231			list_add(&info->node, &vp_dev->virtqueues);232		else233			list_add(&info->node, &vp_dev->slow_virtqueues);234		spin_unlock_irqrestore(&vp_dev->lock, flags);235	} else {236		INIT_LIST_HEAD(&info->node);237	}238 239	*p_info = info;240	return vq;241 242out_info:243	kfree(info);244	return vq;245}246 247static void vp_del_vq(struct virtqueue *vq, struct virtio_pci_vq_info *info)248{249	struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);250	unsigned long flags;251 252	/*253	 * If it fails during re-enable reset vq. This way we won't rejoin254	 * info->node to the queue. Prevent unexpected irqs.255	 */256	if (!vq->reset) {257		spin_lock_irqsave(&vp_dev->lock, flags);258		list_del(&info->node);259		spin_unlock_irqrestore(&vp_dev->lock, flags);260	}261 262	vp_dev->del_vq(info);263	kfree(info);264}265 266/* the config->del_vqs() implementation */267void vp_del_vqs(struct virtio_device *vdev)268{269	struct virtio_pci_device *vp_dev = to_vp_device(vdev);270	struct virtio_pci_vq_info *info;271	struct virtqueue *vq, *n;272	int i;273 274	list_for_each_entry_safe(vq, n, &vdev->vqs, list) {275		info = vp_is_avq(vdev, vq->index) ? vp_dev->admin_vq.info :276						    vp_dev->vqs[vq->index];277 278		if (vp_dev->per_vq_vectors) {279			int v = info->msix_vector;280			if (v != VIRTIO_MSI_NO_VECTOR &&281			    !vp_is_slow_path_vector(v)) {282				int irq = pci_irq_vector(vp_dev->pci_dev, v);283 284				irq_update_affinity_hint(irq, NULL);285				free_irq(irq, vq);286			}287		}288		vp_del_vq(vq, info);289	}290	vp_dev->per_vq_vectors = false;291 292	if (vp_dev->intx_enabled) {293		free_irq(vp_dev->pci_dev->irq, vp_dev);294		vp_dev->intx_enabled = 0;295	}296 297	for (i = 0; i < vp_dev->msix_used_vectors; ++i)298		free_irq(pci_irq_vector(vp_dev->pci_dev, i), vp_dev);299 300	if (vp_dev->msix_affinity_masks) {301		for (i = 0; i < vp_dev->msix_vectors; i++)302			free_cpumask_var(vp_dev->msix_affinity_masks[i]);303	}304 305	if (vp_dev->msix_enabled) {306		/* Disable the vector used for configuration */307		vp_dev->config_vector(vp_dev, VIRTIO_MSI_NO_VECTOR);308 309		pci_free_irq_vectors(vp_dev->pci_dev);310		vp_dev->msix_enabled = 0;311	}312 313	vp_dev->msix_vectors = 0;314	vp_dev->msix_used_vectors = 0;315	kfree(vp_dev->msix_names);316	vp_dev->msix_names = NULL;317	kfree(vp_dev->msix_affinity_masks);318	vp_dev->msix_affinity_masks = NULL;319	kfree(vp_dev->vqs);320	vp_dev->vqs = NULL;321}322 323enum vp_vq_vector_policy {324	VP_VQ_VECTOR_POLICY_EACH,325	VP_VQ_VECTOR_POLICY_SHARED_SLOW,326	VP_VQ_VECTOR_POLICY_SHARED,327};328 329static struct virtqueue *330vp_find_one_vq_msix(struct virtio_device *vdev, int queue_idx,331		    vq_callback_t *callback, const char *name, bool ctx,332		    bool slow_path, int *allocated_vectors,333		    enum vp_vq_vector_policy vector_policy,334		    struct virtio_pci_vq_info **p_info)335{336	struct virtio_pci_device *vp_dev = to_vp_device(vdev);337	struct virtqueue *vq;338	u16 msix_vec;339	int err;340 341	if (!callback)342		msix_vec = VIRTIO_MSI_NO_VECTOR;343	else if (vector_policy == VP_VQ_VECTOR_POLICY_EACH ||344		 (vector_policy == VP_VQ_VECTOR_POLICY_SHARED_SLOW &&345		 !slow_path))346		msix_vec = (*allocated_vectors)++;347	else if (vector_policy != VP_VQ_VECTOR_POLICY_EACH &&348		 slow_path)349		msix_vec = VP_MSIX_CONFIG_VECTOR;350	else351		msix_vec = VP_MSIX_VQ_VECTOR;352	vq = vp_setup_vq(vdev, queue_idx, callback, name, ctx, msix_vec,353			 p_info);354	if (IS_ERR(vq))355		return vq;356 357	if (vector_policy == VP_VQ_VECTOR_POLICY_SHARED ||358	    msix_vec == VIRTIO_MSI_NO_VECTOR ||359	    vp_is_slow_path_vector(msix_vec))360		return vq;361 362	/* allocate per-vq irq if available and necessary */363	snprintf(vp_dev->msix_names[msix_vec], sizeof(*vp_dev->msix_names),364		 "%s-%s", dev_name(&vp_dev->vdev.dev), name);365	err = request_irq(pci_irq_vector(vp_dev->pci_dev, msix_vec),366			  vring_interrupt, 0,367			  vp_dev->msix_names[msix_vec], vq);368	if (err) {369		vp_del_vq(vq, *p_info);370		return ERR_PTR(err);371	}372 373	return vq;374}375 376static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned int nvqs,377			    struct virtqueue *vqs[],378			    struct virtqueue_info vqs_info[],379			    enum vp_vq_vector_policy vector_policy,380			    struct irq_affinity *desc)381{382	struct virtio_pci_device *vp_dev = to_vp_device(vdev);383	struct virtio_pci_admin_vq *avq = &vp_dev->admin_vq;384	struct virtqueue_info *vqi;385	int i, err, nvectors, allocated_vectors, queue_idx = 0;386	struct virtqueue *vq;387	bool per_vq_vectors;388	u16 avq_num = 0;389 390	vp_dev->vqs = kcalloc(nvqs, sizeof(*vp_dev->vqs), GFP_KERNEL);391	if (!vp_dev->vqs)392		return -ENOMEM;393 394	if (vp_dev->avq_index) {395		err = vp_dev->avq_index(vdev, &avq->vq_index, &avq_num);396		if (err)397			goto error_find;398	}399 400	per_vq_vectors = vector_policy != VP_VQ_VECTOR_POLICY_SHARED;401 402	if (per_vq_vectors) {403		/* Best option: one for change interrupt, one per vq. */404		nvectors = 1;405		for (i = 0; i < nvqs; ++i) {406			vqi = &vqs_info[i];407			if (vqi->name && vqi->callback)408				++nvectors;409		}410		if (avq_num && vector_policy == VP_VQ_VECTOR_POLICY_EACH)411			++nvectors;412	} else {413		/* Second best: one for change, shared for all vqs. */414		nvectors = 2;415	}416 417	err = vp_request_msix_vectors(vdev, nvectors, per_vq_vectors, desc);418	if (err)419		goto error_find;420 421	vp_dev->per_vq_vectors = per_vq_vectors;422	allocated_vectors = vp_dev->msix_used_vectors;423	for (i = 0; i < nvqs; ++i) {424		vqi = &vqs_info[i];425		if (!vqi->name) {426			vqs[i] = NULL;427			continue;428		}429		vqs[i] = vp_find_one_vq_msix(vdev, queue_idx++, vqi->callback,430					     vqi->name, vqi->ctx, false,431					     &allocated_vectors, vector_policy,432					     &vp_dev->vqs[i]);433		if (IS_ERR(vqs[i])) {434			err = PTR_ERR(vqs[i]);435			goto error_find;436		}437	}438 439	if (!avq_num)440		return 0;441	sprintf(avq->name, "avq.%u", avq->vq_index);442	vq = vp_find_one_vq_msix(vdev, avq->vq_index, vp_modern_avq_done,443				 avq->name, false, true, &allocated_vectors,444				 vector_policy, &vp_dev->admin_vq.info);445	if (IS_ERR(vq)) {446		err = PTR_ERR(vq);447		goto error_find;448	}449 450	return 0;451 452error_find:453	vp_del_vqs(vdev);454	return err;455}456 457static int vp_find_vqs_intx(struct virtio_device *vdev, unsigned int nvqs,458			    struct virtqueue *vqs[],459			    struct virtqueue_info vqs_info[])460{461	struct virtio_pci_device *vp_dev = to_vp_device(vdev);462	struct virtio_pci_admin_vq *avq = &vp_dev->admin_vq;463	int i, err, queue_idx = 0;464	struct virtqueue *vq;465	u16 avq_num = 0;466 467	vp_dev->vqs = kcalloc(nvqs, sizeof(*vp_dev->vqs), GFP_KERNEL);468	if (!vp_dev->vqs)469		return -ENOMEM;470 471	if (vp_dev->avq_index) {472		err = vp_dev->avq_index(vdev, &avq->vq_index, &avq_num);473		if (err)474			goto out_del_vqs;475	}476 477	err = request_irq(vp_dev->pci_dev->irq, vp_interrupt, IRQF_SHARED,478			dev_name(&vdev->dev), vp_dev);479	if (err)480		goto out_del_vqs;481 482	vp_dev->intx_enabled = 1;483	vp_dev->per_vq_vectors = false;484	for (i = 0; i < nvqs; ++i) {485		struct virtqueue_info *vqi = &vqs_info[i];486 487		if (!vqi->name) {488			vqs[i] = NULL;489			continue;490		}491		vqs[i] = vp_setup_vq(vdev, queue_idx++, vqi->callback,492				     vqi->name, vqi->ctx,493				     VIRTIO_MSI_NO_VECTOR, &vp_dev->vqs[i]);494		if (IS_ERR(vqs[i])) {495			err = PTR_ERR(vqs[i]);496			goto out_del_vqs;497		}498	}499 500	if (!avq_num)501		return 0;502	sprintf(avq->name, "avq.%u", avq->vq_index);503	vq = vp_setup_vq(vdev, queue_idx++, vp_modern_avq_done, avq->name,504			 false, VIRTIO_MSI_NO_VECTOR,505			 &vp_dev->admin_vq.info);506	if (IS_ERR(vq)) {507		err = PTR_ERR(vq);508		goto out_del_vqs;509	}510 511	return 0;512out_del_vqs:513	vp_del_vqs(vdev);514	return err;515}516 517/* the config->find_vqs() implementation */518int vp_find_vqs(struct virtio_device *vdev, unsigned int nvqs,519		struct virtqueue *vqs[], struct virtqueue_info vqs_info[],520		struct irq_affinity *desc)521{522	int err;523 524	/* Try MSI-X with one vector per queue. */525	err = vp_find_vqs_msix(vdev, nvqs, vqs, vqs_info,526			       VP_VQ_VECTOR_POLICY_EACH, desc);527	if (!err)528		return 0;529	/* Fallback: MSI-X with one shared vector for config and530	 * slow path queues, one vector per queue for the rest.531	 */532	err = vp_find_vqs_msix(vdev, nvqs, vqs, vqs_info,533			       VP_VQ_VECTOR_POLICY_SHARED_SLOW, desc);534	if (!err)535		return 0;536	/* Fallback: MSI-X with one vector for config, one shared for queues. */537	err = vp_find_vqs_msix(vdev, nvqs, vqs, vqs_info,538			       VP_VQ_VECTOR_POLICY_SHARED, desc);539	if (!err)540		return 0;541	/* Is there an interrupt? If not give up. */542	if (!(to_vp_device(vdev)->pci_dev->irq))543		return err;544	/* Finally fall back to regular interrupts. */545	return vp_find_vqs_intx(vdev, nvqs, vqs, vqs_info);546}547 548const char *vp_bus_name(struct virtio_device *vdev)549{550	struct virtio_pci_device *vp_dev = to_vp_device(vdev);551 552	return pci_name(vp_dev->pci_dev);553}554 555/* Setup the affinity for a virtqueue:556 * - force the affinity for per vq vector557 * - OR over all affinities for shared MSI558 * - ignore the affinity request if we're using INTX559 */560int vp_set_vq_affinity(struct virtqueue *vq, const struct cpumask *cpu_mask)561{562	struct virtio_device *vdev = vq->vdev;563	struct virtio_pci_device *vp_dev = to_vp_device(vdev);564	struct virtio_pci_vq_info *info = vp_dev->vqs[vq->index];565	struct cpumask *mask;566	unsigned int irq;567 568	if (!vq->callback)569		return -EINVAL;570 571	if (vp_dev->msix_enabled) {572		mask = vp_dev->msix_affinity_masks[info->msix_vector];573		irq = pci_irq_vector(vp_dev->pci_dev, info->msix_vector);574		if (!cpu_mask)575			irq_update_affinity_hint(irq, NULL);576		else {577			cpumask_copy(mask, cpu_mask);578			irq_set_affinity_and_hint(irq, mask);579		}580	}581	return 0;582}583 584const struct cpumask *vp_get_vq_affinity(struct virtio_device *vdev, int index)585{586	struct virtio_pci_device *vp_dev = to_vp_device(vdev);587 588	if (!vp_dev->per_vq_vectors ||589	    vp_dev->vqs[index]->msix_vector == VIRTIO_MSI_NO_VECTOR ||590	    vp_is_slow_path_vector(vp_dev->vqs[index]->msix_vector))591		return NULL;592 593	return pci_irq_get_affinity(vp_dev->pci_dev,594				    vp_dev->vqs[index]->msix_vector);595}596 597#ifdef CONFIG_PM_SLEEP598static int virtio_pci_freeze(struct device *dev)599{600	struct pci_dev *pci_dev = to_pci_dev(dev);601	struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);602	int ret;603 604	ret = virtio_device_freeze(&vp_dev->vdev);605 606	if (!ret)607		pci_disable_device(pci_dev);608	return ret;609}610 611static int virtio_pci_restore(struct device *dev)612{613	struct pci_dev *pci_dev = to_pci_dev(dev);614	struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);615	int ret;616 617	ret = pci_enable_device(pci_dev);618	if (ret)619		return ret;620 621	pci_set_master(pci_dev);622	return virtio_device_restore(&vp_dev->vdev);623}624 625static bool vp_supports_pm_no_reset(struct device *dev)626{627	struct pci_dev *pci_dev = to_pci_dev(dev);628	u16 pmcsr;629 630	if (!pci_dev->pm_cap)631		return false;632 633	pci_read_config_word(pci_dev, pci_dev->pm_cap + PCI_PM_CTRL, &pmcsr);634	if (PCI_POSSIBLE_ERROR(pmcsr)) {635		dev_err(dev, "Unable to query pmcsr");636		return false;637	}638 639	return pmcsr & PCI_PM_CTRL_NO_SOFT_RESET;640}641 642static int virtio_pci_suspend(struct device *dev)643{644	return vp_supports_pm_no_reset(dev) ? 0 : virtio_pci_freeze(dev);645}646 647static int virtio_pci_resume(struct device *dev)648{649	return vp_supports_pm_no_reset(dev) ? 0 : virtio_pci_restore(dev);650}651 652static const struct dev_pm_ops virtio_pci_pm_ops = {653	.suspend = virtio_pci_suspend,654	.resume = virtio_pci_resume,655	.freeze = virtio_pci_freeze,656	.thaw = virtio_pci_restore,657	.poweroff = virtio_pci_freeze,658	.restore = virtio_pci_restore,659};660#endif661 662 663/* Qumranet donated their vendor ID for devices 0x1000 thru 0x10FF. */664static const struct pci_device_id virtio_pci_id_table[] = {665	{ PCI_DEVICE(PCI_VENDOR_ID_REDHAT_QUMRANET, PCI_ANY_ID) },666	{ 0 }667};668 669MODULE_DEVICE_TABLE(pci, virtio_pci_id_table);670 671static void virtio_pci_release_dev(struct device *_d)672{673	struct virtio_device *vdev = dev_to_virtio(_d);674	struct virtio_pci_device *vp_dev = to_vp_device(vdev);675 676	/* As struct device is a kobject, it's not safe to677	 * free the memory (including the reference counter itself)678	 * until it's release callback. */679	kfree(vp_dev);680}681 682static int virtio_pci_probe(struct pci_dev *pci_dev,683			    const struct pci_device_id *id)684{685	struct virtio_pci_device *vp_dev, *reg_dev = NULL;686	int rc;687 688	/* allocate our structure and fill it out */689	vp_dev = kzalloc(sizeof(struct virtio_pci_device), GFP_KERNEL);690	if (!vp_dev)691		return -ENOMEM;692 693	pci_set_drvdata(pci_dev, vp_dev);694	vp_dev->vdev.dev.parent = &pci_dev->dev;695	vp_dev->vdev.dev.release = virtio_pci_release_dev;696	vp_dev->pci_dev = pci_dev;697	INIT_LIST_HEAD(&vp_dev->virtqueues);698	INIT_LIST_HEAD(&vp_dev->slow_virtqueues);699	spin_lock_init(&vp_dev->lock);700 701	/* enable the device */702	rc = pci_enable_device(pci_dev);703	if (rc)704		goto err_enable_device;705 706	if (force_legacy) {707		rc = virtio_pci_legacy_probe(vp_dev);708		/* Also try modern mode if we can't map BAR0 (no IO space). */709		if (rc == -ENODEV || rc == -ENOMEM)710			rc = virtio_pci_modern_probe(vp_dev);711		if (rc)712			goto err_probe;713	} else {714		rc = virtio_pci_modern_probe(vp_dev);715		if (rc == -ENODEV)716			rc = virtio_pci_legacy_probe(vp_dev);717		if (rc)718			goto err_probe;719	}720 721	pci_set_master(pci_dev);722 723	rc = register_virtio_device(&vp_dev->vdev);724	reg_dev = vp_dev;725	if (rc)726		goto err_register;727 728	return 0;729 730err_register:731	if (vp_dev->is_legacy)732		virtio_pci_legacy_remove(vp_dev);733	else734		virtio_pci_modern_remove(vp_dev);735err_probe:736	pci_disable_device(pci_dev);737err_enable_device:738	if (reg_dev)739		put_device(&vp_dev->vdev.dev);740	else741		kfree(vp_dev);742	return rc;743}744 745static void virtio_pci_remove(struct pci_dev *pci_dev)746{747	struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);748	struct device *dev = get_device(&vp_dev->vdev.dev);749 750	/*751	 * Device is marked broken on surprise removal so that virtio upper752	 * layers can abort any ongoing operation.753	 */754	if (!pci_device_is_present(pci_dev))755		virtio_break_device(&vp_dev->vdev);756 757	pci_disable_sriov(pci_dev);758 759	unregister_virtio_device(&vp_dev->vdev);760 761	if (vp_dev->is_legacy)762		virtio_pci_legacy_remove(vp_dev);763	else764		virtio_pci_modern_remove(vp_dev);765 766	pci_disable_device(pci_dev);767	put_device(dev);768}769 770static int virtio_pci_sriov_configure(struct pci_dev *pci_dev, int num_vfs)771{772	struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);773	struct virtio_device *vdev = &vp_dev->vdev;774	int ret;775 776	if (!(vdev->config->get_status(vdev) & VIRTIO_CONFIG_S_DRIVER_OK))777		return -EBUSY;778 779	if (!__virtio_test_bit(vdev, VIRTIO_F_SR_IOV))780		return -EINVAL;781 782	if (pci_vfs_assigned(pci_dev))783		return -EPERM;784 785	if (num_vfs == 0) {786		pci_disable_sriov(pci_dev);787		return 0;788	}789 790	ret = pci_enable_sriov(pci_dev, num_vfs);791	if (ret < 0)792		return ret;793 794	return num_vfs;795}796 797static struct pci_driver virtio_pci_driver = {798	.name		= "virtio-pci",799	.id_table	= virtio_pci_id_table,800	.probe		= virtio_pci_probe,801	.remove		= virtio_pci_remove,802#ifdef CONFIG_PM_SLEEP803	.driver.pm	= &virtio_pci_pm_ops,804#endif805	.sriov_configure = virtio_pci_sriov_configure,806};807 808struct virtio_device *virtio_pci_vf_get_pf_dev(struct pci_dev *pdev)809{810	struct virtio_pci_device *pf_vp_dev;811 812	pf_vp_dev = pci_iov_get_pf_drvdata(pdev, &virtio_pci_driver);813	if (IS_ERR(pf_vp_dev))814		return NULL;815 816	return &pf_vp_dev->vdev;817}818 819module_pci_driver(virtio_pci_driver);820 821MODULE_AUTHOR("Anthony Liguori <aliguori@us.ibm.com>");822MODULE_DESCRIPTION("virtio-pci");823MODULE_LICENSE("GPL");824MODULE_VERSION("1");825