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1// SPDX-License-Identifier: GPL-2.0+2// Copyright 2017 IBM Corp.3#include <linux/sched/mm.h>4#include <linux/mutex.h>5#include <linux/mm.h>6#include <linux/mm_types.h>7#include <linux/mmu_context.h>8#include <linux/mmu_notifier.h>9#include <linux/irqdomain.h>10#include <asm/copro.h>11#include <asm/pnv-ocxl.h>12#include <asm/xive.h>13#include <misc/ocxl.h>14#include "ocxl_internal.h"15#include "trace.h"16 17 18#define SPA_PASID_BITS		1519#define SPA_PASID_MAX		((1 << SPA_PASID_BITS) - 1)20#define SPA_PE_MASK		SPA_PASID_MAX21#define SPA_SPA_SIZE_LOG	22 /* Each SPA is 4 Mb */22 23#define SPA_CFG_SF		(1ull << (63-0))24#define SPA_CFG_TA		(1ull << (63-1))25#define SPA_CFG_HV		(1ull << (63-3))26#define SPA_CFG_UV		(1ull << (63-4))27#define SPA_CFG_XLAT_hpt	(0ull << (63-6)) /* Hashed page table (HPT) mode */28#define SPA_CFG_XLAT_roh	(2ull << (63-6)) /* Radix on HPT mode */29#define SPA_CFG_XLAT_ror	(3ull << (63-6)) /* Radix on Radix mode */30#define SPA_CFG_PR		(1ull << (63-49))31#define SPA_CFG_TC		(1ull << (63-54))32#define SPA_CFG_DR		(1ull << (63-59))33 34#define SPA_XSL_TF		(1ull << (63-3))  /* Translation fault */35#define SPA_XSL_S		(1ull << (63-38)) /* Store operation */36 37#define SPA_PE_VALID		0x8000000038 39struct ocxl_link;40 41struct pe_data {42	struct mm_struct *mm;43	/* callback to trigger when a translation fault occurs */44	void (*xsl_err_cb)(void *data, u64 addr, u64 dsisr);45	/* opaque pointer to be passed to the above callback */46	void *xsl_err_data;47	struct rcu_head rcu;48	struct ocxl_link *link;49	struct mmu_notifier mmu_notifier;50};51 52struct spa {53	struct ocxl_process_element *spa_mem;54	int spa_order;55	struct mutex spa_lock;56	struct radix_tree_root pe_tree; /* Maps PE handles to pe_data */57	char *irq_name;58	int virq;59	void __iomem *reg_dsisr;60	void __iomem *reg_dar;61	void __iomem *reg_tfc;62	void __iomem *reg_pe_handle;63	/*64	 * The following field are used by the memory fault65	 * interrupt handler. We can only have one interrupt at a66	 * time. The NPU won't raise another interrupt until the67	 * previous one has been ack'd by writing to the TFC register68	 */69	struct xsl_fault {70		struct work_struct fault_work;71		u64 pe;72		u64 dsisr;73		u64 dar;74		struct pe_data pe_data;75	} xsl_fault;76};77 78/*79 * A opencapi link can be used be by several PCI functions. We have80 * one link per device slot.81 *82 * A linked list of opencapi links should suffice, as there's a83 * limited number of opencapi slots on a system and lookup is only84 * done when the device is probed85 */86struct ocxl_link {87	struct list_head list;88	struct kref ref;89	int domain;90	int bus;91	int dev;92	void __iomem *arva;     /* ATSD register virtual address */93	spinlock_t atsd_lock;   /* to serialize shootdowns */94	atomic_t irq_available;95	struct spa *spa;96	void *platform_data;97};98static LIST_HEAD(links_list);99static DEFINE_MUTEX(links_list_lock);100 101enum xsl_response {102	CONTINUE,103	ADDRESS_ERROR,104	RESTART,105};106 107 108static void read_irq(struct spa *spa, u64 *dsisr, u64 *dar, u64 *pe)109{110	u64 reg;111 112	*dsisr = in_be64(spa->reg_dsisr);113	*dar = in_be64(spa->reg_dar);114	reg = in_be64(spa->reg_pe_handle);115	*pe = reg & SPA_PE_MASK;116}117 118static void ack_irq(struct spa *spa, enum xsl_response r)119{120	u64 reg = 0;121 122	/* continue is not supported */123	if (r == RESTART)124		reg = PPC_BIT(31);125	else if (r == ADDRESS_ERROR)126		reg = PPC_BIT(30);127	else128		WARN(1, "Invalid irq response %d\n", r);129 130	if (reg) {131		trace_ocxl_fault_ack(spa->spa_mem, spa->xsl_fault.pe,132				spa->xsl_fault.dsisr, spa->xsl_fault.dar, reg);133		out_be64(spa->reg_tfc, reg);134	}135}136 137static void xsl_fault_handler_bh(struct work_struct *fault_work)138{139	vm_fault_t flt = 0;140	unsigned long access, flags, inv_flags = 0;141	enum xsl_response r;142	struct xsl_fault *fault = container_of(fault_work, struct xsl_fault,143					fault_work);144	struct spa *spa = container_of(fault, struct spa, xsl_fault);145 146	int rc;147 148	/*149	 * We must release a reference on mm_users whenever exiting this150	 * function (taken in the memory fault interrupt handler)151	 */152	rc = copro_handle_mm_fault(fault->pe_data.mm, fault->dar, fault->dsisr,153				&flt);154	if (rc) {155		pr_debug("copro_handle_mm_fault failed: %d\n", rc);156		if (fault->pe_data.xsl_err_cb) {157			fault->pe_data.xsl_err_cb(158				fault->pe_data.xsl_err_data,159				fault->dar, fault->dsisr);160		}161		r = ADDRESS_ERROR;162		goto ack;163	}164 165	if (!radix_enabled()) {166		/*167		 * update_mmu_cache() will not have loaded the hash168		 * since current->trap is not a 0x400 or 0x300, so169		 * just call hash_page_mm() here.170		 */171		access = _PAGE_PRESENT | _PAGE_READ;172		if (fault->dsisr & SPA_XSL_S)173			access |= _PAGE_WRITE;174 175		if (get_region_id(fault->dar) != USER_REGION_ID)176			access |= _PAGE_PRIVILEGED;177 178		local_irq_save(flags);179		hash_page_mm(fault->pe_data.mm, fault->dar, access, 0x300,180			inv_flags);181		local_irq_restore(flags);182	}183	r = RESTART;184ack:185	mmput(fault->pe_data.mm);186	ack_irq(spa, r);187}188 189static irqreturn_t xsl_fault_handler(int irq, void *data)190{191	struct ocxl_link *link = data;192	struct spa *spa = link->spa;193	u64 dsisr, dar, pe_handle;194	struct pe_data *pe_data;195	struct ocxl_process_element *pe;196	int pid;197	bool schedule = false;198 199	read_irq(spa, &dsisr, &dar, &pe_handle);200	trace_ocxl_fault(spa->spa_mem, pe_handle, dsisr, dar, -1);201 202	WARN_ON(pe_handle > SPA_PE_MASK);203	pe = spa->spa_mem + pe_handle;204	pid = be32_to_cpu(pe->pid);205	/* We could be reading all null values here if the PE is being206	 * removed while an interrupt kicks in. It's not supposed to207	 * happen if the driver notified the AFU to terminate the208	 * PASID, and the AFU waited for pending operations before209	 * acknowledging. But even if it happens, we won't find a210	 * memory context below and fail silently, so it should be ok.211	 */212	if (!(dsisr & SPA_XSL_TF)) {213		WARN(1, "Invalid xsl interrupt fault register %#llx\n", dsisr);214		ack_irq(spa, ADDRESS_ERROR);215		return IRQ_HANDLED;216	}217 218	rcu_read_lock();219	pe_data = radix_tree_lookup(&spa->pe_tree, pe_handle);220	if (!pe_data) {221		/*222		 * Could only happen if the driver didn't notify the223		 * AFU about PASID termination before removing the PE,224		 * or the AFU didn't wait for all memory access to225		 * have completed.226		 *227		 * Either way, we fail early, but we shouldn't log an228		 * error message, as it is a valid (if unexpected)229		 * scenario230		 */231		rcu_read_unlock();232		pr_debug("Unknown mm context for xsl interrupt\n");233		ack_irq(spa, ADDRESS_ERROR);234		return IRQ_HANDLED;235	}236 237	if (!pe_data->mm) {238		/*239		 * translation fault from a kernel context - an OpenCAPI240		 * device tried to access a bad kernel address241		 */242		rcu_read_unlock();243		pr_warn("Unresolved OpenCAPI xsl fault in kernel context\n");244		ack_irq(spa, ADDRESS_ERROR);245		return IRQ_HANDLED;246	}247	WARN_ON(pe_data->mm->context.id != pid);248 249	if (mmget_not_zero(pe_data->mm)) {250			spa->xsl_fault.pe = pe_handle;251			spa->xsl_fault.dar = dar;252			spa->xsl_fault.dsisr = dsisr;253			spa->xsl_fault.pe_data = *pe_data;254			schedule = true;255			/* mm_users count released by bottom half */256	}257	rcu_read_unlock();258	if (schedule)259		schedule_work(&spa->xsl_fault.fault_work);260	else261		ack_irq(spa, ADDRESS_ERROR);262	return IRQ_HANDLED;263}264 265static void unmap_irq_registers(struct spa *spa)266{267	pnv_ocxl_unmap_xsl_regs(spa->reg_dsisr, spa->reg_dar, spa->reg_tfc,268				spa->reg_pe_handle);269}270 271static int map_irq_registers(struct pci_dev *dev, struct spa *spa)272{273	return pnv_ocxl_map_xsl_regs(dev, &spa->reg_dsisr, &spa->reg_dar,274				&spa->reg_tfc, &spa->reg_pe_handle);275}276 277static int setup_xsl_irq(struct pci_dev *dev, struct ocxl_link *link)278{279	struct spa *spa = link->spa;280	int rc;281	int hwirq;282 283	rc = pnv_ocxl_get_xsl_irq(dev, &hwirq);284	if (rc)285		return rc;286 287	rc = map_irq_registers(dev, spa);288	if (rc)289		return rc;290 291	spa->irq_name = kasprintf(GFP_KERNEL, "ocxl-xsl-%x-%x-%x",292				link->domain, link->bus, link->dev);293	if (!spa->irq_name) {294		dev_err(&dev->dev, "Can't allocate name for xsl interrupt\n");295		rc = -ENOMEM;296		goto err_xsl;297	}298	/*299	 * At some point, we'll need to look into allowing a higher300	 * number of interrupts. Could we have an IRQ domain per link?301	 */302	spa->virq = irq_create_mapping(NULL, hwirq);303	if (!spa->virq) {304		dev_err(&dev->dev,305			"irq_create_mapping failed for translation interrupt\n");306		rc = -EINVAL;307		goto err_name;308	}309 310	dev_dbg(&dev->dev, "hwirq %d mapped to virq %d\n", hwirq, spa->virq);311 312	rc = request_irq(spa->virq, xsl_fault_handler, 0, spa->irq_name,313			link);314	if (rc) {315		dev_err(&dev->dev,316			"request_irq failed for translation interrupt: %d\n",317			rc);318		rc = -EINVAL;319		goto err_mapping;320	}321	return 0;322 323err_mapping:324	irq_dispose_mapping(spa->virq);325err_name:326	kfree(spa->irq_name);327err_xsl:328	unmap_irq_registers(spa);329	return rc;330}331 332static void release_xsl_irq(struct ocxl_link *link)333{334	struct spa *spa = link->spa;335 336	if (spa->virq) {337		free_irq(spa->virq, link);338		irq_dispose_mapping(spa->virq);339	}340	kfree(spa->irq_name);341	unmap_irq_registers(spa);342}343 344static int alloc_spa(struct pci_dev *dev, struct ocxl_link *link)345{346	struct spa *spa;347 348	spa = kzalloc(sizeof(struct spa), GFP_KERNEL);349	if (!spa)350		return -ENOMEM;351 352	mutex_init(&spa->spa_lock);353	INIT_RADIX_TREE(&spa->pe_tree, GFP_KERNEL);354	INIT_WORK(&spa->xsl_fault.fault_work, xsl_fault_handler_bh);355 356	spa->spa_order = SPA_SPA_SIZE_LOG - PAGE_SHIFT;357	spa->spa_mem = (struct ocxl_process_element *)358		__get_free_pages(GFP_KERNEL | __GFP_ZERO, spa->spa_order);359	if (!spa->spa_mem) {360		dev_err(&dev->dev, "Can't allocate Shared Process Area\n");361		kfree(spa);362		return -ENOMEM;363	}364	pr_debug("Allocated SPA for %x:%x:%x at %p\n", link->domain, link->bus,365		link->dev, spa->spa_mem);366 367	link->spa = spa;368	return 0;369}370 371static void free_spa(struct ocxl_link *link)372{373	struct spa *spa = link->spa;374 375	pr_debug("Freeing SPA for %x:%x:%x\n", link->domain, link->bus,376		link->dev);377 378	if (spa && spa->spa_mem) {379		free_pages((unsigned long) spa->spa_mem, spa->spa_order);380		kfree(spa);381		link->spa = NULL;382	}383}384 385static int alloc_link(struct pci_dev *dev, int PE_mask, struct ocxl_link **out_link)386{387	struct ocxl_link *link;388	int rc;389 390	link = kzalloc(sizeof(struct ocxl_link), GFP_KERNEL);391	if (!link)392		return -ENOMEM;393 394	kref_init(&link->ref);395	link->domain = pci_domain_nr(dev->bus);396	link->bus = dev->bus->number;397	link->dev = PCI_SLOT(dev->devfn);398	atomic_set(&link->irq_available, MAX_IRQ_PER_LINK);399	spin_lock_init(&link->atsd_lock);400 401	rc = alloc_spa(dev, link);402	if (rc)403		goto err_free;404 405	rc = setup_xsl_irq(dev, link);406	if (rc)407		goto err_spa;408 409	/* platform specific hook */410	rc = pnv_ocxl_spa_setup(dev, link->spa->spa_mem, PE_mask,411				&link->platform_data);412	if (rc)413		goto err_xsl_irq;414 415	/* if link->arva is not defeined, MMIO registers are not used to416	 * generate TLB invalidate. PowerBus snooping is enabled.417	 * Otherwise, PowerBus snooping is disabled. TLB Invalidates are418	 * initiated using MMIO registers.419	 */420	pnv_ocxl_map_lpar(dev, mfspr(SPRN_LPID), 0, &link->arva);421 422	*out_link = link;423	return 0;424 425err_xsl_irq:426	release_xsl_irq(link);427err_spa:428	free_spa(link);429err_free:430	kfree(link);431	return rc;432}433 434static void free_link(struct ocxl_link *link)435{436	release_xsl_irq(link);437	free_spa(link);438	kfree(link);439}440 441int ocxl_link_setup(struct pci_dev *dev, int PE_mask, void **link_handle)442{443	int rc = 0;444	struct ocxl_link *link;445 446	mutex_lock(&links_list_lock);447	list_for_each_entry(link, &links_list, list) {448		/* The functions of a device all share the same link */449		if (link->domain == pci_domain_nr(dev->bus) &&450			link->bus == dev->bus->number &&451			link->dev == PCI_SLOT(dev->devfn)) {452			kref_get(&link->ref);453			*link_handle = link;454			goto unlock;455		}456	}457	rc = alloc_link(dev, PE_mask, &link);458	if (rc)459		goto unlock;460 461	list_add(&link->list, &links_list);462	*link_handle = link;463unlock:464	mutex_unlock(&links_list_lock);465	return rc;466}467EXPORT_SYMBOL_GPL(ocxl_link_setup);468 469static void release_xsl(struct kref *ref)470{471	struct ocxl_link *link = container_of(ref, struct ocxl_link, ref);472 473	if (link->arva) {474		pnv_ocxl_unmap_lpar(link->arva);475		link->arva = NULL;476	}477 478	list_del(&link->list);479	/* call platform code before releasing data */480	pnv_ocxl_spa_release(link->platform_data);481	free_link(link);482}483 484void ocxl_link_release(struct pci_dev *dev, void *link_handle)485{486	struct ocxl_link *link = link_handle;487 488	mutex_lock(&links_list_lock);489	kref_put(&link->ref, release_xsl);490	mutex_unlock(&links_list_lock);491}492EXPORT_SYMBOL_GPL(ocxl_link_release);493 494static void arch_invalidate_secondary_tlbs(struct mmu_notifier *mn,495					struct mm_struct *mm,496					unsigned long start, unsigned long end)497{498	struct pe_data *pe_data = container_of(mn, struct pe_data, mmu_notifier);499	struct ocxl_link *link = pe_data->link;500	unsigned long addr, pid, page_size = PAGE_SIZE;501 502	pid = mm->context.id;503	trace_ocxl_mmu_notifier_range(start, end, pid);504 505	spin_lock(&link->atsd_lock);506	for (addr = start; addr < end; addr += page_size)507		pnv_ocxl_tlb_invalidate(link->arva, pid, addr, page_size);508	spin_unlock(&link->atsd_lock);509}510 511static const struct mmu_notifier_ops ocxl_mmu_notifier_ops = {512	.arch_invalidate_secondary_tlbs = arch_invalidate_secondary_tlbs,513};514 515static u64 calculate_cfg_state(bool kernel)516{517	u64 state;518 519	state = SPA_CFG_DR;520	if (mfspr(SPRN_LPCR) & LPCR_TC)521		state |= SPA_CFG_TC;522	if (radix_enabled())523		state |= SPA_CFG_XLAT_ror;524	else525		state |= SPA_CFG_XLAT_hpt;526	state |= SPA_CFG_HV;527	if (kernel) {528		if (mfmsr() & MSR_SF)529			state |= SPA_CFG_SF;530	} else {531		state |= SPA_CFG_PR;532		if (!test_tsk_thread_flag(current, TIF_32BIT))533			state |= SPA_CFG_SF;534	}535	return state;536}537 538int ocxl_link_add_pe(void *link_handle, int pasid, u32 pidr, u32 tidr,539		u64 amr, u16 bdf, struct mm_struct *mm,540		void (*xsl_err_cb)(void *data, u64 addr, u64 dsisr),541		void *xsl_err_data)542{543	struct ocxl_link *link = link_handle;544	struct spa *spa = link->spa;545	struct ocxl_process_element *pe;546	int pe_handle, rc = 0;547	struct pe_data *pe_data;548 549	BUILD_BUG_ON(sizeof(struct ocxl_process_element) != 128);550	if (pasid > SPA_PASID_MAX)551		return -EINVAL;552 553	mutex_lock(&spa->spa_lock);554	pe_handle = pasid & SPA_PE_MASK;555	pe = spa->spa_mem + pe_handle;556 557	if (pe->software_state) {558		rc = -EBUSY;559		goto unlock;560	}561 562	pe_data = kmalloc(sizeof(*pe_data), GFP_KERNEL);563	if (!pe_data) {564		rc = -ENOMEM;565		goto unlock;566	}567 568	pe_data->mm = mm;569	pe_data->xsl_err_cb = xsl_err_cb;570	pe_data->xsl_err_data = xsl_err_data;571	pe_data->link = link;572	pe_data->mmu_notifier.ops = &ocxl_mmu_notifier_ops;573 574	memset(pe, 0, sizeof(struct ocxl_process_element));575	pe->config_state = cpu_to_be64(calculate_cfg_state(pidr == 0));576	pe->pasid = cpu_to_be32(pasid << (31 - 19));577	pe->bdf = cpu_to_be16(bdf);578	pe->lpid = cpu_to_be32(mfspr(SPRN_LPID));579	pe->pid = cpu_to_be32(pidr);580	pe->tid = cpu_to_be32(tidr);581	pe->amr = cpu_to_be64(amr);582	pe->software_state = cpu_to_be32(SPA_PE_VALID);583 584	/*585	 * For user contexts, register a copro so that TLBIs are seen586	 * by the nest MMU. If we have a kernel context, TLBIs are587	 * already global.588	 */589	if (mm) {590		mm_context_add_copro(mm);591		if (link->arva) {592			/* Use MMIO registers for the TLB Invalidate593			 * operations.594			 */595			trace_ocxl_init_mmu_notifier(pasid, mm->context.id);596			mmu_notifier_register(&pe_data->mmu_notifier, mm);597		}598	}599 600	/*601	 * Barrier is to make sure PE is visible in the SPA before it602	 * is used by the device. It also helps with the global TLBI603	 * invalidation604	 */605	mb();606	radix_tree_insert(&spa->pe_tree, pe_handle, pe_data);607 608	/*609	 * The mm must stay valid for as long as the device uses it. We610	 * lower the count when the context is removed from the SPA.611	 *612	 * We grab mm_count (and not mm_users), as we don't want to613	 * end up in a circular dependency if a process mmaps its614	 * mmio, therefore incrementing the file ref count when615	 * calling mmap(), and forgets to unmap before exiting. In616	 * that scenario, when the kernel handles the death of the617	 * process, the file is not cleaned because unmap was not618	 * called, and the mm wouldn't be freed because we would still619	 * have a reference on mm_users. Incrementing mm_count solves620	 * the problem.621	 */622	if (mm)623		mmgrab(mm);624	trace_ocxl_context_add(current->pid, spa->spa_mem, pasid, pidr, tidr);625unlock:626	mutex_unlock(&spa->spa_lock);627	return rc;628}629EXPORT_SYMBOL_GPL(ocxl_link_add_pe);630 631int ocxl_link_update_pe(void *link_handle, int pasid, __u16 tid)632{633	struct ocxl_link *link = link_handle;634	struct spa *spa = link->spa;635	struct ocxl_process_element *pe;636	int pe_handle, rc;637 638	if (pasid > SPA_PASID_MAX)639		return -EINVAL;640 641	pe_handle = pasid & SPA_PE_MASK;642	pe = spa->spa_mem + pe_handle;643 644	mutex_lock(&spa->spa_lock);645 646	pe->tid = cpu_to_be32(tid);647 648	/*649	 * The barrier makes sure the PE is updated650	 * before we clear the NPU context cache below, so that the651	 * old PE cannot be reloaded erroneously.652	 */653	mb();654 655	/*656	 * hook to platform code657	 * On powerpc, the entry needs to be cleared from the context658	 * cache of the NPU.659	 */660	rc = pnv_ocxl_spa_remove_pe_from_cache(link->platform_data, pe_handle);661	WARN_ON(rc);662 663	mutex_unlock(&spa->spa_lock);664	return rc;665}666 667int ocxl_link_remove_pe(void *link_handle, int pasid)668{669	struct ocxl_link *link = link_handle;670	struct spa *spa = link->spa;671	struct ocxl_process_element *pe;672	struct pe_data *pe_data;673	int pe_handle, rc;674 675	if (pasid > SPA_PASID_MAX)676		return -EINVAL;677 678	/*679	 * About synchronization with our memory fault handler:680	 *681	 * Before removing the PE, the driver is supposed to have682	 * notified the AFU, which should have cleaned up and make683	 * sure the PASID is no longer in use, including pending684	 * interrupts. However, there's no way to be sure...685	 *686	 * We clear the PE and remove the context from our radix687	 * tree. From that point on, any new interrupt for that688	 * context will fail silently, which is ok. As mentioned689	 * above, that's not expected, but it could happen if the690	 * driver or AFU didn't do the right thing.691	 *692	 * There could still be a bottom half running, but we don't693	 * need to wait/flush, as it is managing a reference count on694	 * the mm it reads from the radix tree.695	 */696	pe_handle = pasid & SPA_PE_MASK;697	pe = spa->spa_mem + pe_handle;698 699	mutex_lock(&spa->spa_lock);700 701	if (!(be32_to_cpu(pe->software_state) & SPA_PE_VALID)) {702		rc = -EINVAL;703		goto unlock;704	}705 706	trace_ocxl_context_remove(current->pid, spa->spa_mem, pasid,707				be32_to_cpu(pe->pid), be32_to_cpu(pe->tid));708 709	memset(pe, 0, sizeof(struct ocxl_process_element));710	/*711	 * The barrier makes sure the PE is removed from the SPA712	 * before we clear the NPU context cache below, so that the713	 * old PE cannot be reloaded erroneously.714	 */715	mb();716 717	/*718	 * hook to platform code719	 * On powerpc, the entry needs to be cleared from the context720	 * cache of the NPU.721	 */722	rc = pnv_ocxl_spa_remove_pe_from_cache(link->platform_data, pe_handle);723	WARN_ON(rc);724 725	pe_data = radix_tree_delete(&spa->pe_tree, pe_handle);726	if (!pe_data) {727		WARN(1, "Couldn't find pe data when removing PE\n");728	} else {729		if (pe_data->mm) {730			if (link->arva) {731				trace_ocxl_release_mmu_notifier(pasid,732								pe_data->mm->context.id);733				mmu_notifier_unregister(&pe_data->mmu_notifier,734							pe_data->mm);735				spin_lock(&link->atsd_lock);736				pnv_ocxl_tlb_invalidate(link->arva,737							pe_data->mm->context.id,738							0ull,739							PAGE_SIZE);740				spin_unlock(&link->atsd_lock);741			}742			mm_context_remove_copro(pe_data->mm);743			mmdrop(pe_data->mm);744		}745		kfree_rcu(pe_data, rcu);746	}747unlock:748	mutex_unlock(&spa->spa_lock);749	return rc;750}751EXPORT_SYMBOL_GPL(ocxl_link_remove_pe);752 753int ocxl_link_irq_alloc(void *link_handle, int *hw_irq)754{755	struct ocxl_link *link = link_handle;756	int irq;757 758	if (atomic_dec_if_positive(&link->irq_available) < 0)759		return -ENOSPC;760 761	irq = xive_native_alloc_irq();762	if (!irq) {763		atomic_inc(&link->irq_available);764		return -ENXIO;765	}766 767	*hw_irq = irq;768	return 0;769}770EXPORT_SYMBOL_GPL(ocxl_link_irq_alloc);771 772void ocxl_link_free_irq(void *link_handle, int hw_irq)773{774	struct ocxl_link *link = link_handle;775 776	xive_native_free_irq(hw_irq);777	atomic_inc(&link->irq_available);778}779EXPORT_SYMBOL_GPL(ocxl_link_free_irq);780