summaryrefslogtreecommitdiff
path: root/arch/s390/kvm/pci.c
diff options
context:
space:
mode:
authorMatthew Rosato <mjrosato@linux.ibm.com>2022-06-06 23:33:16 +0300
committerChristian Borntraeger <borntraeger@linux.ibm.com>2022-07-11 10:54:28 +0300
commit98b1d33dac5fd09060486762c02fd1a78baeb1e0 (patch)
treed497644d8dd17f4d2d4681f109c3d8da434a9b8f /arch/s390/kvm/pci.c
parent6438e30714abd1bf7408356d3e86127d1fb379c0 (diff)
downloadlinux-98b1d33dac5fd09060486762c02fd1a78baeb1e0.tar.xz
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: Christian Borntraeger <borntraeger@linux.ibm.com> Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com> Link: https://lore.kernel.org/r/20220606203325.110625-13-mjrosato@linux.ibm.com Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Diffstat (limited to 'arch/s390/kvm/pci.c')
-rw-r--r--arch/s390/kvm/pci.c160
1 files changed, 160 insertions, 0 deletions
diff --git a/arch/s390/kvm/pci.c b/arch/s390/kvm/pci.c
index e27191ea27c4..d566551d3018 100644
--- a/arch/s390/kvm/pci.c
+++ b/arch/s390/kvm/pci.c
@@ -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);
+}