Commit 98b1d33d authored by Matthew Rosato's avatar Matthew Rosato Committed by Christian Borntraeger
Browse files

KVM: s390: pci: do initial setup for AEN interpretation 



Initial setup for Adapter Event Notification Interpretation for zPCI
passthrough devices.  Specifically, allocate a structure for forwarding of
adapter events and pass the address of this structure to firmware.

Reviewed-by: default avatarChristian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: default avatarMatthew Rosato <mjrosato@linux.ibm.com>
Link: https://lore.kernel.org/r/20220606203325.110625-13-mjrosato@linux.ibm.com


Signed-off-by: default avatarChristian Borntraeger <borntraeger@linux.ibm.com>
parent 6438e307

arch/s390/include/asm/pci.h

+4 −0
Original line number Diff line number Diff line
@@ -9,6 +9,7 @@ 
#include <asm-generic/pci.h>

#include <asm/pci_clp.h>

#include <asm/pci_debug.h>

#include <asm/pci_insn.h>

#include <asm/sclp.h>



#define PCIBIOS_MIN_IO		0x1000
@@ -204,6 +205,9 @@ extern const struct attribute_group *zpci_attr_groups[]; 
extern unsigned int s390_pci_force_floating __initdata;

extern unsigned int s390_pci_no_rid;



extern union zpci_sic_iib *zpci_aipb;

extern struct airq_iv *zpci_aif_sbv;



/* -----------------------------------------------------------------------------

  Prototypes

----------------------------------------------------------------------------- */

arch/s390/include/asm/pci_insn.h

+12 −0
Original line number Diff line number Diff line
@@ -101,6 +101,7 @@ struct zpci_fib { 
/* Set Interruption Controls Operation Controls  */

#define	SIC_IRQ_MODE_ALL		0

#define	SIC_IRQ_MODE_SINGLE		1

#define	SIC_SET_AENI_CONTROLS		2

#define	SIC_IRQ_MODE_DIRECT		4

#define	SIC_IRQ_MODE_D_ALL		16

#define	SIC_IRQ_MODE_D_SINGLE		17
@@ -127,9 +128,20 @@ struct zpci_cdiib { 
	u64 : 64;

} __packed __aligned(8);



/* adapter interruption parameters block */

struct zpci_aipb {

	u64 faisb;

	u64 gait;

	u16 : 13;

	u16 afi : 3;

	u32 : 32;

	u16 faal;

} __packed __aligned(8);



union zpci_sic_iib {

	struct zpci_diib diib;

	struct zpci_cdiib cdiib;

	struct zpci_aipb aipb;

};



DECLARE_STATIC_KEY_FALSE(have_mio);

arch/s390/kvm/interrupt.c

+14 −0
Original line number Diff line number Diff line
@@ -32,6 +32,7 @@ 
#include "kvm-s390.h"

#include "gaccess.h"

#include "trace-s390.h"

#include "pci.h"



#define PFAULT_INIT 0x0600

#define PFAULT_DONE 0x0680
@@ -3328,6 +3329,11 @@ void kvm_s390_gib_destroy(void) 
{

	if (!gib)

		return;

	if (kvm_s390_pci_interp_allowed() && aift) {

		mutex_lock(&aift->aift_lock);

		kvm_s390_pci_aen_exit();

		mutex_unlock(&aift->aift_lock);

	}

	chsc_sgib(0);

	unregister_adapter_interrupt(&gib_alert_irq);

	free_page((unsigned long)gib);
@@ -3365,6 +3371,14 @@ int kvm_s390_gib_init(u8 nisc) 
		goto out_unreg_gal;

	}



	if (kvm_s390_pci_interp_allowed()) {

		if (kvm_s390_pci_aen_init(nisc)) {

			pr_err("Initializing AEN for PCI failed\n");

			rc = -EIO;

			goto out_unreg_gal;

		}

	}



	KVM_EVENT(3, "gib 0x%pK (nisc=%d) initialized", gib, gib->nisc);

	goto out;

arch/s390/kvm/kvm-s390.c

+11 −0
Original line number Diff line number Diff line
@@ -47,6 +47,7 @@ 
#include <asm/fpu/api.h>

#include "kvm-s390.h"

#include "gaccess.h"

#include "pci.h"



#define CREATE_TRACE_POINTS

#include "trace.h"
@@ -502,6 +503,14 @@ int kvm_arch_init(void *opaque) 
		goto out;

	}



	if (kvm_s390_pci_interp_allowed()) {

		rc = kvm_s390_pci_init();

		if (rc) {

			pr_err("Unable to allocate AIFT for PCI\n");

			goto out;

		}

	}



	rc = kvm_s390_gib_init(GAL_ISC);

	if (rc)

		goto out;
@@ -516,6 +525,8 @@ int kvm_arch_init(void *opaque) 
void kvm_arch_exit(void)

{

	kvm_s390_gib_destroy();

	if (kvm_s390_pci_interp_allowed())

		kvm_s390_pci_exit();

	debug_unregister(kvm_s390_dbf);

	debug_unregister(kvm_s390_dbf_uv);

}

arch/s390/kvm/pci.c

+160 −0
Original line number Diff line number Diff line
@@ -9,8 +9,149 @@ 


#include <linux/kvm_host.h>

#include <linux/pci.h>

#include <asm/pci.h>

#include <asm/pci_insn.h>

#include "pci.h"



struct zpci_aift *aift;



static inline int __set_irq_noiib(u16 ctl, u8 isc)

{

	union zpci_sic_iib iib = {{0}};



	return zpci_set_irq_ctrl(ctl, isc, &iib);

}



void kvm_s390_pci_aen_exit(void)

{

	unsigned long flags;

	struct kvm_zdev **gait_kzdev;



	lockdep_assert_held(&aift->aift_lock);



	/*

	 * Contents of the aipb remain registered for the life of the host

	 * kernel, the information preserved in zpci_aipb and zpci_aif_sbv

	 * in case we insert the KVM module again later.  Clear the AIFT

	 * information and free anything not registered with underlying

	 * firmware.

	 */

	spin_lock_irqsave(&aift->gait_lock, flags);

	gait_kzdev = aift->kzdev;

	aift->gait = NULL;

	aift->sbv = NULL;

	aift->kzdev = NULL;

	spin_unlock_irqrestore(&aift->gait_lock, flags);



	kfree(gait_kzdev);

}



static int zpci_setup_aipb(u8 nisc)

{

	struct page *page;

	int size, rc;



	zpci_aipb = kzalloc(sizeof(union zpci_sic_iib), GFP_KERNEL);

	if (!zpci_aipb)

		return -ENOMEM;



	aift->sbv = airq_iv_create(ZPCI_NR_DEVICES, AIRQ_IV_ALLOC, 0);

	if (!aift->sbv) {

		rc = -ENOMEM;

		goto free_aipb;

	}

	zpci_aif_sbv = aift->sbv;

	size = get_order(PAGE_ALIGN(ZPCI_NR_DEVICES *

						sizeof(struct zpci_gaite)));

	page = alloc_pages(GFP_KERNEL | __GFP_ZERO, size);

	if (!page) {

		rc = -ENOMEM;

		goto free_sbv;

	}

	aift->gait = (struct zpci_gaite *)page_to_phys(page);



	zpci_aipb->aipb.faisb = virt_to_phys(aift->sbv->vector);

	zpci_aipb->aipb.gait = virt_to_phys(aift->gait);

	zpci_aipb->aipb.afi = nisc;

	zpci_aipb->aipb.faal = ZPCI_NR_DEVICES;



	/* Setup Adapter Event Notification Interpretation */

	if (zpci_set_irq_ctrl(SIC_SET_AENI_CONTROLS, 0, zpci_aipb)) {

		rc = -EIO;

		goto free_gait;

	}



	return 0;



free_gait:

	free_pages((unsigned long)aift->gait, size);

free_sbv:

	airq_iv_release(aift->sbv);

	zpci_aif_sbv = NULL;

free_aipb:

	kfree(zpci_aipb);

	zpci_aipb = NULL;



	return rc;

}



static int zpci_reset_aipb(u8 nisc)

{

	/*

	 * AEN registration can only happen once per system boot.  If

	 * an aipb already exists then AEN was already registered and

	 * we can re-use the aipb contents.  This can only happen if

	 * the KVM module was removed and re-inserted.  However, we must

	 * ensure that the same forwarding ISC is used as this is assigned

	 * during KVM module load.

	 */

	if (zpci_aipb->aipb.afi != nisc)

		return -EINVAL;



	aift->sbv = zpci_aif_sbv;

	aift->gait = (struct zpci_gaite *)zpci_aipb->aipb.gait;



	return 0;

}



int kvm_s390_pci_aen_init(u8 nisc)

{

	int rc = 0;



	/* If already enabled for AEN, bail out now */

	if (aift->gait || aift->sbv)

		return -EPERM;



	mutex_lock(&aift->aift_lock);

	aift->kzdev = kcalloc(ZPCI_NR_DEVICES, sizeof(struct kvm_zdev),

			      GFP_KERNEL);

	if (!aift->kzdev) {

		rc = -ENOMEM;

		goto unlock;

	}



	if (!zpci_aipb)

		rc = zpci_setup_aipb(nisc);

	else

		rc = zpci_reset_aipb(nisc);

	if (rc)

		goto free_zdev;



	/* Enable floating IRQs */

	if (__set_irq_noiib(SIC_IRQ_MODE_SINGLE, nisc)) {

		rc = -EIO;

		kvm_s390_pci_aen_exit();

	}



	goto unlock;



free_zdev:

	kfree(aift->kzdev);

unlock:

	mutex_unlock(&aift->aift_lock);

	return rc;

}



static int kvm_s390_pci_dev_open(struct zpci_dev *zdev)

{

	struct kvm_zdev *kzdev;
@@ -34,3 +175,22 @@ static void kvm_s390_pci_dev_release(struct zpci_dev *zdev) 
	zdev->kzdev = NULL;

	kfree(kzdev);

}



int kvm_s390_pci_init(void)

{

	aift = kzalloc(sizeof(struct zpci_aift), GFP_KERNEL);

	if (!aift)

		return -ENOMEM;



	spin_lock_init(&aift->gait_lock);

	mutex_init(&aift->aift_lock);



	return 0;

}



void kvm_s390_pci_exit(void)

{

	mutex_destroy(&aift->aift_lock);



	kfree(aift);

}