summaryrefslogtreecommitdiff
path: root/drivers/virtio/virtio_pci_common.h
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/virtio/virtio_pci_common.h')
-rw-r--r--drivers/virtio/virtio_pci_common.h165
1 files changed, 165 insertions, 0 deletions
diff --git a/drivers/virtio/virtio_pci_common.h b/drivers/virtio/virtio_pci_common.h
new file mode 100644
index 000000000..28ee4e56b
--- /dev/null
+++ b/drivers/virtio/virtio_pci_common.h
@@ -0,0 +1,165 @@
+#ifndef _DRIVERS_VIRTIO_VIRTIO_PCI_COMMON_H
+#define _DRIVERS_VIRTIO_VIRTIO_PCI_COMMON_H
+/*
+ * Virtio PCI driver - APIs for common functionality for all device versions
+ *
+ * This module allows virtio devices to be used over a virtual PCI device.
+ * This can be used with QEMU based VMMs like KVM or Xen.
+ *
+ * Copyright IBM Corp. 2007
+ * Copyright Red Hat, Inc. 2014
+ *
+ * Authors:
+ * Anthony Liguori <aliguori@us.ibm.com>
+ * Rusty Russell <rusty@rustcorp.com.au>
+ * Michael S. Tsirkin <mst@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/list.h>
+#include <linux/pci.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/virtio.h>
+#include <linux/virtio_config.h>
+#include <linux/virtio_ring.h>
+#include <linux/virtio_pci.h>
+#include <linux/highmem.h>
+#include <linux/spinlock.h>
+
+struct virtio_pci_vq_info {
+ /* the actual virtqueue */
+ struct virtqueue *vq;
+
+ /* the number of entries in the queue */
+ int num;
+
+ /* the virtual address of the ring queue */
+ void *queue;
+
+ /* the list node for the virtqueues list */
+ struct list_head node;
+
+ /* MSI-X vector (or none) */
+ unsigned msix_vector;
+};
+
+/* Our device structure */
+struct virtio_pci_device {
+ struct virtio_device vdev;
+ struct pci_dev *pci_dev;
+
+ /* In legacy mode, these two point to within ->legacy. */
+ /* Where to read and clear interrupt */
+ u8 __iomem *isr;
+
+ /* Modern only fields */
+ /* The IO mapping for the PCI config space (non-legacy mode) */
+ struct virtio_pci_common_cfg __iomem *common;
+ /* Device-specific data (non-legacy mode) */
+ void __iomem *device;
+ /* Base of vq notifications (non-legacy mode). */
+ void __iomem *notify_base;
+
+ /* So we can sanity-check accesses. */
+ size_t notify_len;
+ size_t device_len;
+
+ /* Capability for when we need to map notifications per-vq. */
+ int notify_map_cap;
+
+ /* Multiply queue_notify_off by this value. (non-legacy mode). */
+ u32 notify_offset_multiplier;
+
+ /* Legacy only field */
+ /* the IO mapping for the PCI config space */
+ void __iomem *ioaddr;
+
+ /* a list of queues so we can dispatch IRQs */
+ spinlock_t lock;
+ struct list_head virtqueues;
+
+ /* array of all queues for house-keeping */
+ struct virtio_pci_vq_info **vqs;
+
+ /* MSI-X support */
+ int msix_enabled;
+ int intx_enabled;
+ struct msix_entry *msix_entries;
+ cpumask_var_t *msix_affinity_masks;
+ /* Name strings for interrupts. This size should be enough,
+ * and I'm too lazy to allocate each name separately. */
+ char (*msix_names)[256];
+ /* Number of available vectors */
+ unsigned msix_vectors;
+ /* Vectors allocated, excluding per-vq vectors if any */
+ unsigned msix_used_vectors;
+
+ /* Whether we have vector per vq */
+ bool per_vq_vectors;
+
+ struct virtqueue *(*setup_vq)(struct virtio_pci_device *vp_dev,
+ struct virtio_pci_vq_info *info,
+ unsigned idx,
+ void (*callback)(struct virtqueue *vq),
+ const char *name,
+ u16 msix_vec);
+ void (*del_vq)(struct virtio_pci_vq_info *info);
+
+ u16 (*config_vector)(struct virtio_pci_device *vp_dev, u16 vector);
+};
+
+/* Constants for MSI-X */
+/* Use first vector for configuration changes, second and the rest for
+ * virtqueues Thus, we need at least 2 vectors for MSI. */
+enum {
+ VP_MSIX_CONFIG_VECTOR = 0,
+ VP_MSIX_VQ_VECTOR = 1,
+};
+
+/* Convert a generic virtio device to our structure */
+static struct virtio_pci_device *to_vp_device(struct virtio_device *vdev)
+{
+ return container_of(vdev, struct virtio_pci_device, vdev);
+}
+
+/* wait for pending irq handlers */
+void vp_synchronize_vectors(struct virtio_device *vdev);
+/* the notify function used when creating a virt queue */
+bool vp_notify(struct virtqueue *vq);
+/* the config->del_vqs() implementation */
+void vp_del_vqs(struct virtio_device *vdev);
+/* the config->find_vqs() implementation */
+int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs,
+ struct virtqueue *vqs[],
+ vq_callback_t *callbacks[],
+ const char *names[]);
+const char *vp_bus_name(struct virtio_device *vdev);
+
+/* Setup the affinity for a virtqueue:
+ * - force the affinity for per vq vector
+ * - OR over all affinities for shared MSI
+ * - ignore the affinity request if we're using INTX
+ */
+int vp_set_vq_affinity(struct virtqueue *vq, int cpu);
+
+#if IS_ENABLED(CONFIG_VIRTIO_PCI_LEGACY)
+int virtio_pci_legacy_probe(struct virtio_pci_device *);
+void virtio_pci_legacy_remove(struct virtio_pci_device *);
+#else
+static inline int virtio_pci_legacy_probe(struct virtio_pci_device *vp_dev)
+{
+ return -ENODEV;
+}
+static inline void virtio_pci_legacy_remove(struct virtio_pci_device *vp_dev)
+{
+}
+#endif
+int virtio_pci_modern_probe(struct virtio_pci_device *);
+void virtio_pci_modern_remove(struct virtio_pci_device *);
+
+#endif