Revert "virtio_pci: don't duplicate the msix_enable flag in struct pci_dev"

[karo-tx-linux.git] / drivers / virtio / virtio_pci_common.c

diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c
index 590534910dc617836e18c91b6576410a0299de26..3921b0a2439ed775a6a10323cb350d4b6974c47c 100644 (file)
--- a/drivers/virtio/virtio_pci_common.c
+++ b/drivers/virtio/virtio_pci_common.c
@@ -125,7 +125,7 @@ void vp_del_vqs(struct virtio_device *vdev)
 
        vp_remove_vqs(vdev);
 
-       if (vp_dev->pci_dev->msix_enabled) {
+       if (vp_dev->msix_enabled) {
                for (i = 0; i < vp_dev->msix_vectors; i++)
                        free_cpumask_var(vp_dev->msix_affinity_masks[i]);
 
@@ -143,13 +143,13 @@ void vp_del_vqs(struct virtio_device *vdev)
 
 static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned nvqs,
                struct virtqueue *vqs[], vq_callback_t *callbacks[],
-               const char * const names[], struct irq_affinity *desc)
+               const char * const names[], 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);
-       int i, j, err = -ENOMEM, allocated_vectors, nvectors;
+       int i, err = -ENOMEM, allocated_vectors, nvectors;
        unsigned flags = PCI_IRQ_MSIX;
-       bool shared = false;
        u16 msix_vec;
 
        if (desc) {
@@ -162,16 +162,12 @@ static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned nvqs,
                if (callbacks[i])
                        nvectors++;
 
-       /* Try one vector per queue first. */
-       err = pci_alloc_irq_vectors_affinity(vp_dev->pci_dev, nvectors,
-                       nvectors, flags, desc);
-       if (err < 0) {
-               /* Fallback to one vector for config, one shared for queues. */
-               shared = true;
+       if (per_vq_vectors) {
+               err = pci_alloc_irq_vectors_affinity(vp_dev->pci_dev, nvectors,
+                               nvectors, flags, desc);
+       } else {
                err = pci_alloc_irq_vectors(vp_dev->pci_dev, 2, 2,
                                PCI_IRQ_MSIX);
-               if (err < 0)
-                       return err;
        }
        if (err < 0)
                return err;
@@ -199,7 +195,7 @@ static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned nvqs,
        err = request_irq(pci_irq_vector(vp_dev->pci_dev, 0), vp_config_changed,
                        0, vp_dev->msix_names[0], vp_dev);
        if (err)
-               goto out_free_msix_affinity_masks;
+               goto out_free_irq_vectors;
 
        /* Verify we had enough resources to assign the vector */
        if (vp_dev->config_vector(vp_dev, 0) == VIRTIO_MSI_NO_VECTOR) {
@@ -212,7 +208,7 @@ static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned nvqs,
        if (!vp_dev->msix_vector_map)
                goto out_disable_config_irq;
 
-       allocated_vectors = j = 1; /* vector 0 is the config interrupt */
+       allocated_vectors = 1; /* vector 0 is the config interrupt */
        for (i = 0; i < nvqs; ++i) {
                if (!names[i]) {
                        vqs[i] = NULL;
@@ -236,28 +232,24 @@ static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned nvqs,
                        continue;
                }
 
-               snprintf(vp_dev->msix_names[j],
+               snprintf(vp_dev->msix_names[i + 1],
                         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[j], vqs[i]);
+                                 vp_dev->msix_names[i + 1], 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;
                }
                vp_dev->msix_vector_map[i] = msix_vec;
-               j++;
 
-               /*
-                * Use a different vector for each queue if they are available,
-                * else share the same vector for all VQs.
-                */
-               if (!shared)
+               if (per_vq_vectors)
                        allocated_vectors++;
        }
 
+       vp_dev->msix_enabled = 1;
        return 0;
 
 out_remove_vqs:
@@ -320,9 +312,15 @@ int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 {
        int err;
 
-       err = vp_find_vqs_msix(vdev, nvqs, vqs, callbacks, names, desc);
+       /* Try MSI-X with one vector per queue. */
+       err = vp_find_vqs_msix(vdev, nvqs, vqs, callbacks, names, true, desc);
+       if (!err)
+               return 0;
+       /* Fallback: MSI-X with one vector for config, one shared for queues. */
+       err = vp_find_vqs_msix(vdev, nvqs, vqs, callbacks, names, false, desc);
        if (!err)
                return 0;
+       /* Finally fall back to regular interrupts. */
        return vp_find_vqs_intx(vdev, nvqs, vqs, callbacks, names);
 }
 
@@ -346,7 +344,7 @@ int vp_set_vq_affinity(struct virtqueue *vq, int cpu)
        if (!vq->callback)
                return -EINVAL;
 
-       if (vp_dev->pci_dev->msix_enabled) {
+       if (vp_dev->msix_enabled) {
                int vec = vp_dev->msix_vector_map[vq->index];
                struct cpumask *mask = vp_dev->msix_affinity_masks[vec];
                unsigned int irq = pci_irq_vector(vp_dev->pci_dev, vec);