diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c index 3921b0a2439e..d99029d3892e 100644 --- a/drivers/virtio/virtio_pci_common.c +++ b/drivers/virtio/virtio_pci_common.c @@ -33,8 +33,10 @@ void vp_synchronize_vectors(struct virtio_device *vdev) struct virtio_pci_device *vp_dev = to_vp_device(vdev); int i; - synchronize_irq(pci_irq_vector(vp_dev->pci_dev, 0)); - for (i = 1; i < vp_dev->msix_vectors; i++) + if (vp_dev->intx_enabled) + synchronize_irq(vp_dev->pci_dev->irq); + + for (i = 0; i < vp_dev->msix_vectors; ++i) synchronize_irq(pci_irq_vector(vp_dev->pci_dev, i)); } @@ -97,10 +99,79 @@ static irqreturn_t vp_interrupt(int irq, void *opaque) return vp_vring_interrupt(irq, opaque); } -static void vp_remove_vqs(struct virtio_device *vdev) +static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors, + bool per_vq_vectors, struct irq_affinity *desc) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + const char *name = dev_name(&vp_dev->vdev.dev); + unsigned i, v; + int err = -ENOMEM; + + vp_dev->msix_vectors = nvectors; + + vp_dev->msix_names = kmalloc(nvectors * sizeof *vp_dev->msix_names, + GFP_KERNEL); + if (!vp_dev->msix_names) + goto error; + vp_dev->msix_affinity_masks + = kzalloc(nvectors * sizeof *vp_dev->msix_affinity_masks, + GFP_KERNEL); + if (!vp_dev->msix_affinity_masks) + goto error; + for (i = 0; i < nvectors; ++i) + if (!alloc_cpumask_var(&vp_dev->msix_affinity_masks[i], + GFP_KERNEL)) + goto error; + + err = pci_alloc_irq_vectors_affinity(vp_dev->pci_dev, nvectors, + nvectors, PCI_IRQ_MSIX | + (desc ? PCI_IRQ_AFFINITY : 0), + desc); + if (err < 0) + goto error; + vp_dev->msix_enabled = 1; + + /* Set the vector used for configuration */ + v = vp_dev->msix_used_vectors; + snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names, + "%s-config", name); + err = request_irq(pci_irq_vector(vp_dev->pci_dev, v), + vp_config_changed, 0, vp_dev->msix_names[v], + vp_dev); + if (err) + goto error; + ++vp_dev->msix_used_vectors; + + v = vp_dev->config_vector(vp_dev, v); + /* Verify we had enough resources to assign the vector */ + if (v == VIRTIO_MSI_NO_VECTOR) { + err = -EBUSY; + goto error; + } + + if (!per_vq_vectors) { + /* Shared vector for all VQs */ + v = vp_dev->msix_used_vectors; + snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names, + "%s-virtqueues", name); + err = request_irq(pci_irq_vector(vp_dev->pci_dev, v), + vp_vring_interrupt, 0, vp_dev->msix_names[v], + vp_dev); + if (err) + goto error; + ++vp_dev->msix_used_vectors; + } + return 0; +error: + return err; +} + +/* the config->del_vqs() implementation */ +void vp_del_vqs(struct virtio_device *vdev) { struct virtio_pci_device *vp_dev = to_vp_device(vdev); struct virtqueue *vq, *n; + int i; list_for_each_entry_safe(vq, n, &vdev->vqs, list) { if (vp_dev->msix_vector_map) { @@ -112,33 +183,35 @@ static void vp_remove_vqs(struct virtio_device *vdev) } vp_dev->del_vq(vq); } -} -/* the config->del_vqs() implementation */ -void vp_del_vqs(struct virtio_device *vdev) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - int i; + if (vp_dev->intx_enabled) { + free_irq(vp_dev->pci_dev->irq, vp_dev); + vp_dev->intx_enabled = 0; + } - if (WARN_ON_ONCE(list_empty_careful(&vdev->vqs))) - return; + for (i = 0; i < vp_dev->msix_used_vectors; ++i) + free_irq(pci_irq_vector(vp_dev->pci_dev, i), vp_dev); - vp_remove_vqs(vdev); - - if (vp_dev->msix_enabled) { - for (i = 0; i < vp_dev->msix_vectors; i++) + for (i = 0; i < vp_dev->msix_vectors; i++) + if (vp_dev->msix_affinity_masks[i]) free_cpumask_var(vp_dev->msix_affinity_masks[i]); + if (vp_dev->msix_enabled) { /* Disable the vector used for configuration */ vp_dev->config_vector(vp_dev, VIRTIO_MSI_NO_VECTOR); - kfree(vp_dev->msix_affinity_masks); - kfree(vp_dev->msix_names); - kfree(vp_dev->msix_vector_map); + pci_free_irq_vectors(vp_dev->pci_dev); + vp_dev->msix_enabled = 0; } - free_irq(pci_irq_vector(vp_dev->pci_dev, 0), vp_dev); - pci_free_irq_vectors(vp_dev->pci_dev); + vp_dev->msix_vectors = 0; + vp_dev->msix_used_vectors = 0; + kfree(vp_dev->msix_names); + vp_dev->msix_names = NULL; + kfree(vp_dev->msix_affinity_masks); + vp_dev->msix_affinity_masks = NULL; + kfree(vp_dev->msix_vector_map); + vp_dev->msix_vector_map = NULL; } static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned nvqs, @@ -147,128 +220,80 @@ static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned nvqs, struct irq_affinity *desc) { struct virtio_pci_device *vp_dev = to_vp_device(vdev); - const char *name = dev_name(&vp_dev->vdev.dev); - int i, err = -ENOMEM, allocated_vectors, nvectors; - unsigned flags = PCI_IRQ_MSIX; u16 msix_vec; - - if (desc) { - flags |= PCI_IRQ_AFFINITY; - desc->pre_vectors++; /* virtio config vector */ - } - - nvectors = 1; - for (i = 0; i < nvqs; i++) - if (callbacks[i]) - nvectors++; + int i, err, nvectors, allocated_vectors; if (per_vq_vectors) { - err = pci_alloc_irq_vectors_affinity(vp_dev->pci_dev, nvectors, - nvectors, flags, desc); + /* Best option: one for change interrupt, one per vq. */ + nvectors = 1; + for (i = 0; i < nvqs; ++i) + if (callbacks[i]) + ++nvectors; } else { - err = pci_alloc_irq_vectors(vp_dev->pci_dev, 2, 2, - PCI_IRQ_MSIX); - } - if (err < 0) - return err; - - vp_dev->msix_vectors = nvectors; - vp_dev->msix_names = kmalloc_array(nvectors, - sizeof(*vp_dev->msix_names), GFP_KERNEL); - if (!vp_dev->msix_names) - goto out_free_irq_vectors; - - vp_dev->msix_affinity_masks = kcalloc(nvectors, - sizeof(*vp_dev->msix_affinity_masks), GFP_KERNEL); - if (!vp_dev->msix_affinity_masks) - goto out_free_msix_names; - - for (i = 0; i < nvectors; ++i) { - if (!alloc_cpumask_var(&vp_dev->msix_affinity_masks[i], - GFP_KERNEL)) - goto out_free_msix_affinity_masks; + /* Second best: one for change, shared for all vqs. */ + nvectors = 2; } - /* Set the vector used for configuration */ - snprintf(vp_dev->msix_names[0], sizeof(*vp_dev->msix_names), - "%s-config", name); - err = request_irq(pci_irq_vector(vp_dev->pci_dev, 0), vp_config_changed, - 0, vp_dev->msix_names[0], vp_dev); + err = vp_request_msix_vectors(vdev, nvectors, per_vq_vectors, + per_vq_vectors ? desc : NULL); if (err) - goto out_free_irq_vectors; + goto error_find; - /* Verify we had enough resources to assign the vector */ - if (vp_dev->config_vector(vp_dev, 0) == VIRTIO_MSI_NO_VECTOR) { - err = -EBUSY; - goto out_free_config_irq; + if (per_vq_vectors) { + vp_dev->msix_vector_map = kmalloc_array(nvqs, + sizeof(*vp_dev->msix_vector_map), GFP_KERNEL); + if (!vp_dev->msix_vector_map) + goto error_find; } - vp_dev->msix_vector_map = kmalloc_array(nvqs, - sizeof(*vp_dev->msix_vector_map), GFP_KERNEL); - if (!vp_dev->msix_vector_map) - goto out_disable_config_irq; - - allocated_vectors = 1; /* vector 0 is the config interrupt */ + allocated_vectors = vp_dev->msix_used_vectors; for (i = 0; i < nvqs; ++i) { if (!names[i]) { vqs[i] = NULL; continue; } - if (callbacks[i]) - msix_vec = allocated_vectors; - else + if (!callbacks[i]) msix_vec = VIRTIO_MSI_NO_VECTOR; - + else if (per_vq_vectors) + msix_vec = allocated_vectors++; + else + msix_vec = VP_MSIX_VQ_VECTOR; vqs[i] = vp_dev->setup_vq(vp_dev, i, callbacks[i], names[i], msix_vec); if (IS_ERR(vqs[i])) { err = PTR_ERR(vqs[i]); - goto out_remove_vqs; + goto error_find; } + if (!per_vq_vectors) + continue; + if (msix_vec == VIRTIO_MSI_NO_VECTOR) { vp_dev->msix_vector_map[i] = VIRTIO_MSI_NO_VECTOR; continue; } - snprintf(vp_dev->msix_names[i + 1], - sizeof(*vp_dev->msix_names), "%s-%s", + /* allocate per-vq irq if available and necessary */ + snprintf(vp_dev->msix_names[msix_vec], + sizeof *vp_dev->msix_names, + "%s-%s", dev_name(&vp_dev->vdev.dev), names[i]); err = request_irq(pci_irq_vector(vp_dev->pci_dev, msix_vec), - vring_interrupt, IRQF_SHARED, - vp_dev->msix_names[i + 1], vqs[i]); + vring_interrupt, 0, + vp_dev->msix_names[msix_vec], + vqs[i]); if (err) { /* don't free this irq on error */ vp_dev->msix_vector_map[i] = VIRTIO_MSI_NO_VECTOR; - goto out_remove_vqs; + goto error_find; } vp_dev->msix_vector_map[i] = msix_vec; - - if (per_vq_vectors) - allocated_vectors++; } - - vp_dev->msix_enabled = 1; return 0; -out_remove_vqs: - vp_remove_vqs(vdev); - kfree(vp_dev->msix_vector_map); -out_disable_config_irq: - vp_dev->config_vector(vp_dev, VIRTIO_MSI_NO_VECTOR); -out_free_config_irq: - free_irq(pci_irq_vector(vp_dev->pci_dev, 0), vp_dev); -out_free_msix_affinity_masks: - for (i = 0; i < nvectors; i++) { - if (vp_dev->msix_affinity_masks[i]) - free_cpumask_var(vp_dev->msix_affinity_masks[i]); - } - kfree(vp_dev->msix_affinity_masks); -out_free_msix_names: - kfree(vp_dev->msix_names); -out_free_irq_vectors: - pci_free_irq_vectors(vp_dev->pci_dev); +error_find: + vp_del_vqs(vdev); return err; } @@ -282,8 +307,9 @@ static int vp_find_vqs_intx(struct virtio_device *vdev, unsigned nvqs, err = request_irq(vp_dev->pci_dev->irq, vp_interrupt, IRQF_SHARED, dev_name(&vdev->dev), vp_dev); if (err) - return err; + goto out_del_vqs; + vp_dev->intx_enabled = 1; for (i = 0; i < nvqs; ++i) { if (!names[i]) { vqs[i] = NULL; @@ -293,15 +319,13 @@ static int vp_find_vqs_intx(struct virtio_device *vdev, unsigned nvqs, VIRTIO_MSI_NO_VECTOR); if (IS_ERR(vqs[i])) { err = PTR_ERR(vqs[i]); - goto out_remove_vqs; + goto out_del_vqs; } } return 0; - -out_remove_vqs: - vp_remove_vqs(vdev); - free_irq(pci_irq_vector(vp_dev->pci_dev, 0), vp_dev); +out_del_vqs: + vp_del_vqs(vdev); return err; } diff --git a/drivers/virtio/virtio_pci_common.h b/drivers/virtio/virtio_pci_common.h index c8074997fd28..3cdabba8415e 100644 --- a/drivers/virtio/virtio_pci_common.h +++ b/drivers/virtio/virtio_pci_common.h @@ -66,12 +66,16 @@ struct virtio_pci_device { /* MSI-X support */ int msix_enabled; + int intx_enabled; 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]; - /* Total Number of MSI-X vectors (including per-VQ ones). */ - int msix_vectors; + /* Number of available vectors */ + unsigned msix_vectors; + /* Vectors allocated, excluding per-vq vectors if any */ + unsigned msix_used_vectors; + /* Map of per-VQ MSI-X vectors, may be NULL */ unsigned *msix_vector_map; @@ -85,6 +89,14 @@ struct virtio_pci_device { 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) {