qemu_vfio_pci_init_irq() allows us to initialize any type of IRQ,
but only one. Introduce qemu_vfio_pci_msix_init_irqs() which is
specific to MSIX IRQ type, and allow us to use multiple IRQs
(thus passing multiple eventfd notifiers).
All eventfd notifiers are initialized with the special '-1' value
meaning "un-assigned".
Signed-off-by: Philippe Mathieu-Daudé
---
include/qemu/vfio-helpers.h | 6 +++-
util/vfio-helpers.c | 65 -
util/trace-events | 1 +
3 files changed, 70 insertions(+), 2 deletions(-)
diff --git a/include/qemu/vfio-helpers.h b/include/qemu/vfio-helpers.h
index 4b97a904e93..492072cba2f 100644
--- a/include/qemu/vfio-helpers.h
+++ b/include/qemu/vfio-helpers.h
@@ -1,11 +1,13 @@
/*
* QEMU VFIO helpers
*
- * Copyright 2016 - 2018 Red Hat, Inc.
+ * Copyright 2016 - 2020 Red Hat, Inc.
*
* Authors:
* Fam Zheng
+ * Philippe Mathieu-Daudé
*
+ * SPDX-License-Identifier: GPL-2.0-or-later
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*/
@@ -29,5 +31,7 @@ void qemu_vfio_pci_unmap_bar(QEMUVFIOState *s, int index,
void *bar,
uint64_t offset, uint64_t size);
int qemu_vfio_pci_init_irq(QEMUVFIOState *s, EventNotifier *e,
int irq_type, Error **errp);
+int qemu_vfio_pci_msix_init_irqs(QEMUVFIOState *s,
+ unsigned *irq_count, Error **errp);
#endif
diff --git a/util/vfio-helpers.c b/util/vfio-helpers.c
index 874d76c2a2a..d88e2c7dc1f 100644
--- a/util/vfio-helpers.c
+++ b/util/vfio-helpers.c
@@ -1,11 +1,13 @@
/*
* VFIO utility
*
- * Copyright 2016 - 2018 Red Hat, Inc.
+ * Copyright 2016 - 2020 Red Hat, Inc.
*
* Authors:
* Fam Zheng
+ * Philippe Mathieu-Daudé
*
+ * SPDX-License-Identifier: GPL-2.0-or-later
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*/
@@ -230,6 +232,67 @@ int qemu_vfio_pci_init_irq(QEMUVFIOState *s, EventNotifier
*e,
return 0;
}
+/**
+ * Initialize device MSIX IRQs and register event notifiers.
+ * @irq_count: pointer to number of MSIX IRQs to initialize
+ *
+ * If the number of IRQs requested exceeds the available on the device,
+ * store the number of available IRQs in @irq_count and return -EOVERFLOW.
+ */
+int qemu_vfio_pci_msix_init_irqs(QEMUVFIOState *s,
+ unsigned *irq_count, Error **errp)
+{
+int r;
+size_t irq_set_size;
+struct vfio_irq_set *irq_set;
+struct vfio_irq_info irq_info = {
+.argsz = sizeof(irq_info),
+.index = VFIO_PCI_MSIX_IRQ_INDEX
+};
+
+if (ioctl(s->device, VFIO_DEVICE_GET_IRQ_INFO, _info)) {
+error_setg_errno(errp, errno, "Failed to get device interrupt info");
+return -errno;
+}
+trace_qemu_vfio_msix_info_irqs(irq_info.count, *irq_count);
+if (irq_info.count < *irq_count) {
+error_setg(errp, "Not enough device interrupts available");
+*irq_count = irq_info.count;
+return -EOVERFLOW;
+}
+if (!(irq_info.flags & VFIO_IRQ_INFO_EVENTFD)) {
+error_setg(errp, "Device interrupt doesn't support eventfd");
+return -EINVAL;
+}
+
+irq_set_size = sizeof(*irq_set) + *irq_count * sizeof(int32_t);
+irq_set = g_malloc0(irq_set_size);
+
+/* Get to a known IRQ state */
+*irq_set = (struct vfio_irq_set) {
+.argsz = irq_set_size,
+.flags = VFIO_IRQ_SET_DATA_EVENTFD | VFIO_IRQ_SET_ACTION_TRIGGER,
+.index = VFIO_PCI_MSIX_IRQ_INDEX,
+.start = 0,
+.count = *irq_count,
+};
+
+for (unsigned i = 0; i < *irq_count; i++) {
+((int32_t *)_set->data)[i] = -1; /* un-assigned: skip */
+}
+r = ioctl(s->device, VFIO_DEVICE_SET_IRQS, irq_set);
+g_free(irq_set);
+if (r < 0) {
+error_setg_errno(errp, errno, "Failed to setup device interrupts");
+return -errno;
+} else if (r > 0) {
+error_setg(errp, "Not enough device interrupts available");
+*irq_count = r;
+return -EOVERFLOW;
+}
+return 0;
+}
+
static int qemu_vfio_pci_read_config(QEMUVFIOState *s, void *buf,
int size, int ofs)
{
diff --git a/util/trace-events b/util/trace-events
index 3c36def9f30..ec93578b125 100644
--- a/util/trace-events
+++ b/util/trace-events
@@ -87,6 +87,7 @@ qemu_vfio_do_mapping(void *s, void *host, uint64_t iova,
size_t size) "s %p host
qemu_vfio_dma_map(void *s, void *host, size_t size, bool temporary, uint64_t
*iova) "s %p host %p size 0x%zx temporary %d %p"
qemu_vfio_dma_mapped(void *s, void *host, uint64_t iova, size_t size) "s %p
host %p <-> iova 0x%"PRIx64" size 0x%zx"
qemu_vfio_dma_unmap(void *s, void *host) "s %p host %p"
+qemu_vfio_msix_info_irqs(uint32_t count, unsigned asked) "msix irqs %"PRIu32"
(asked: %u)"
