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authorCédric Le Goater <clg@kaod.org>2019-04-18 12:39:38 +0200
committerPaul Mackerras <paulus@ozlabs.org>2019-04-30 19:35:16 +1000
commit6520ca64cde71b75dae54f3fcb33517a93d82486 (patch)
tree878b5eb4c434f2c5bf8fb112770149ecb688452a /arch/powerpc/kvm
parent39e9af3de5ca936098bc80ebe14401426673c208 (diff)
downloadlinux-6520ca64cde71b75dae54f3fcb33517a93d82486.tar.bz2
KVM: PPC: Book3S HV: XIVE: Add a mapping for the source ESB pages
Each source is associated with an Event State Buffer (ESB) with a even/odd pair of pages which provides commands to manage the source: to trigger, to EOI, to turn off the source for instance. The custom VM fault handler will deduce the guest IRQ number from the offset of the fault, and the ESB page of the associated XIVE interrupt will be inserted into the VMA using the internal structure caching information on the interrupts. Signed-off-by: Cédric Le Goater <clg@kaod.org> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Diffstat (limited to 'arch/powerpc/kvm')
-rw-r--r--arch/powerpc/kvm/book3s_xive_native.c57
1 files changed, 57 insertions, 0 deletions
diff --git a/arch/powerpc/kvm/book3s_xive_native.c b/arch/powerpc/kvm/book3s_xive_native.c
index f5314da0cb45..465eb90ff23e 100644
--- a/arch/powerpc/kvm/book3s_xive_native.c
+++ b/arch/powerpc/kvm/book3s_xive_native.c
@@ -165,6 +165,59 @@ bail:
return rc;
}
+static vm_fault_t xive_native_esb_fault(struct vm_fault *vmf)
+{
+ struct vm_area_struct *vma = vmf->vma;
+ struct kvm_device *dev = vma->vm_file->private_data;
+ struct kvmppc_xive *xive = dev->private;
+ struct kvmppc_xive_src_block *sb;
+ struct kvmppc_xive_irq_state *state;
+ struct xive_irq_data *xd;
+ u32 hw_num;
+ u16 src;
+ u64 page;
+ unsigned long irq;
+ u64 page_offset;
+
+ /*
+ * Linux/KVM uses a two pages ESB setting, one for trigger and
+ * one for EOI
+ */
+ page_offset = vmf->pgoff - vma->vm_pgoff;
+ irq = page_offset / 2;
+
+ sb = kvmppc_xive_find_source(xive, irq, &src);
+ if (!sb) {
+ pr_devel("%s: source %lx not found !\n", __func__, irq);
+ return VM_FAULT_SIGBUS;
+ }
+
+ state = &sb->irq_state[src];
+ kvmppc_xive_select_irq(state, &hw_num, &xd);
+
+ arch_spin_lock(&sb->lock);
+
+ /*
+ * first/even page is for trigger
+ * second/odd page is for EOI and management.
+ */
+ page = page_offset % 2 ? xd->eoi_page : xd->trig_page;
+ arch_spin_unlock(&sb->lock);
+
+ if (WARN_ON(!page)) {
+ pr_err("%s: acessing invalid ESB page for source %lx !\n",
+ __func__, irq);
+ return VM_FAULT_SIGBUS;
+ }
+
+ vmf_insert_pfn(vma, vmf->address, page >> PAGE_SHIFT);
+ return VM_FAULT_NOPAGE;
+}
+
+static const struct vm_operations_struct xive_native_esb_vmops = {
+ .fault = xive_native_esb_fault,
+};
+
static vm_fault_t xive_native_tima_fault(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
@@ -194,6 +247,10 @@ static int kvmppc_xive_native_mmap(struct kvm_device *dev,
if (vma_pages(vma) > 4)
return -EINVAL;
vma->vm_ops = &xive_native_tima_vmops;
+ } else if (vma->vm_pgoff == KVM_XIVE_ESB_PAGE_OFFSET) {
+ if (vma_pages(vma) > KVMPPC_XIVE_NR_IRQS * 2)
+ return -EINVAL;
+ vma->vm_ops = &xive_native_esb_vmops;
} else {
return -EINVAL;
}