[PATCH] vmw_vmci: switch to pci_irq_alloc_vectors

From: Christoph Hellwig
Date: Wed Feb 01 2017 - 09:43:10 EST


Cleans up the IRQ management code a lot, including removing a lot of
state from the per-device structure.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
drivers/misc/vmw_vmci/vmci_guest.c | 75 ++++++++++----------------------------
include/linux/vmw_vmci_defs.h | 7 ----
2 files changed, 20 insertions(+), 62 deletions(-)

diff --git a/drivers/misc/vmw_vmci/vmci_guest.c b/drivers/misc/vmw_vmci/vmci_guest.c
index 189b325..9d65954 100644
--- a/drivers/misc/vmw_vmci/vmci_guest.c
+++ b/drivers/misc/vmw_vmci/vmci_guest.c
@@ -54,10 +54,7 @@ struct vmci_guest_device {
struct device *dev; /* PCI device we are attached to */
void __iomem *iobase;

- unsigned int irq;
- unsigned int intr_type;
bool exclusive_vectors;
- struct msix_entry msix_entries[VMCI_MAX_INTRS];

struct tasklet_struct datagram_tasklet;
struct tasklet_struct bm_tasklet;
@@ -369,30 +366,6 @@ static void vmci_process_bitmap(unsigned long data)
}

/*
- * Enable MSI-X. Try exclusive vectors first, then shared vectors.
- */
-static int vmci_enable_msix(struct pci_dev *pdev,
- struct vmci_guest_device *vmci_dev)
-{
- int i;
- int result;
-
- for (i = 0; i < VMCI_MAX_INTRS; ++i) {
- vmci_dev->msix_entries[i].entry = i;
- vmci_dev->msix_entries[i].vector = i;
- }
-
- result = pci_enable_msix_exact(pdev,
- vmci_dev->msix_entries, VMCI_MAX_INTRS);
- if (result == 0)
- vmci_dev->exclusive_vectors = true;
- else if (result == -ENOSPC)
- result = pci_enable_msix_exact(pdev, vmci_dev->msix_entries, 1);
-
- return result;
-}
-
-/*
* Interrupt handler for legacy or MSI interrupt, or for first MSI-X
* interrupt (vector VMCI_INTR_DATAGRAM).
*/
@@ -406,7 +379,7 @@ static irqreturn_t vmci_interrupt(int irq, void *_dev)
* Otherwise we must read the ICR to determine what to do.
*/

- if (dev->intr_type == VMCI_INTR_TYPE_MSIX && dev->exclusive_vectors) {
+ if (dev->exclusive_vectors) {
tasklet_schedule(&dev->datagram_tasklet);
} else {
unsigned int icr;
@@ -491,7 +464,6 @@ static int vmci_guest_probe_device(struct pci_dev *pdev,
}

vmci_dev->dev = &pdev->dev;
- vmci_dev->intr_type = VMCI_INTR_TYPE_INTX;
vmci_dev->exclusive_vectors = false;
vmci_dev->iobase = iobase;

@@ -592,26 +564,26 @@ static int vmci_guest_probe_device(struct pci_dev *pdev,
* Enable interrupts. Try MSI-X first, then MSI, and then fallback on
* legacy interrupts.
*/
- if (!vmci_disable_msix && !vmci_enable_msix(pdev, vmci_dev)) {
- vmci_dev->intr_type = VMCI_INTR_TYPE_MSIX;
- vmci_dev->irq = vmci_dev->msix_entries[0].vector;
- } else if (!vmci_disable_msi && !pci_enable_msi(pdev)) {
- vmci_dev->intr_type = VMCI_INTR_TYPE_MSI;
- vmci_dev->irq = pdev->irq;
+ error = pci_alloc_irq_vectors(pdev, VMCI_MAX_INTRS, VMCI_MAX_INTRS,
+ PCI_IRQ_MSIX);
+ if (error) {
+ error = pci_alloc_irq_vectors(pdev, 1, 1,
+ PCI_IRQ_MSIX | PCI_IRQ_MSI | PCI_IRQ_LEGACY);
+ if (error)
+ goto err_remove_bitmap;
} else {
- vmci_dev->intr_type = VMCI_INTR_TYPE_INTX;
- vmci_dev->irq = pdev->irq;
+ vmci_dev->exclusive_vectors = true;
}

/*
* Request IRQ for legacy or MSI interrupts, or for first
* MSI-X vector.
*/
- error = request_irq(vmci_dev->irq, vmci_interrupt, IRQF_SHARED,
- KBUILD_MODNAME, vmci_dev);
+ error = request_irq(pci_irq_vector(pdev, 0), vmci_interrupt,
+ IRQF_SHARED, KBUILD_MODNAME, vmci_dev);
if (error) {
dev_err(&pdev->dev, "Irq %u in use: %d\n",
- vmci_dev->irq, error);
+ pci_irq_vector(pdev, 0), error);
goto err_disable_msi;
}

@@ -622,13 +594,13 @@ static int vmci_guest_probe_device(struct pci_dev *pdev,
* between the vectors.
*/
if (vmci_dev->exclusive_vectors) {
- error = request_irq(vmci_dev->msix_entries[1].vector,
+ error = request_irq(pci_irq_vector(pdev, 1),
vmci_interrupt_bm, 0, KBUILD_MODNAME,
vmci_dev);
if (error) {
dev_err(&pdev->dev,
"Failed to allocate irq %u: %d\n",
- vmci_dev->msix_entries[1].vector, error);
+ pci_irq_vector(pdev, 1), error);
goto err_free_irq;
}
}
@@ -651,15 +623,12 @@ static int vmci_guest_probe_device(struct pci_dev *pdev,
return 0;

err_free_irq:
- free_irq(vmci_dev->irq, vmci_dev);
+ free_irq(pci_irq_vector(pdev, 0), vmci_dev);
tasklet_kill(&vmci_dev->datagram_tasklet);
tasklet_kill(&vmci_dev->bm_tasklet);

err_disable_msi:
- if (vmci_dev->intr_type == VMCI_INTR_TYPE_MSIX)
- pci_disable_msix(pdev);
- else if (vmci_dev->intr_type == VMCI_INTR_TYPE_MSI)
- pci_disable_msi(pdev);
+ pci_free_irq_vectors(pdev);

vmci_err = vmci_event_unsubscribe(ctx_update_sub_id);
if (vmci_err < VMCI_SUCCESS)
@@ -719,14 +688,10 @@ static void vmci_guest_remove_device(struct pci_dev *pdev)
* MSI-X, we might have multiple vectors, each with their own
* IRQ, which we must free too.
*/
- free_irq(vmci_dev->irq, vmci_dev);
- if (vmci_dev->intr_type == VMCI_INTR_TYPE_MSIX) {
- if (vmci_dev->exclusive_vectors)
- free_irq(vmci_dev->msix_entries[1].vector, vmci_dev);
- pci_disable_msix(pdev);
- } else if (vmci_dev->intr_type == VMCI_INTR_TYPE_MSI) {
- pci_disable_msi(pdev);
- }
+ if (vmci_dev->exclusive_vectors)
+ free_irq(pci_irq_vector(pdev, 1), vmci_dev);
+ free_irq(pci_irq_vector(pdev, 0), vmci_dev);
+ pci_free_irq_vectors(pdev);

tasklet_kill(&vmci_dev->datagram_tasklet);
tasklet_kill(&vmci_dev->bm_tasklet);
diff --git a/include/linux/vmw_vmci_defs.h b/include/linux/vmw_vmci_defs.h
index 1bd31a3..b724ef7 100644
--- a/include/linux/vmw_vmci_defs.h
+++ b/include/linux/vmw_vmci_defs.h
@@ -54,13 +54,6 @@
#define VMCI_IMR_DATAGRAM 0x1
#define VMCI_IMR_NOTIFICATION 0x2

-/* Interrupt type. */
-enum {
- VMCI_INTR_TYPE_INTX = 0,
- VMCI_INTR_TYPE_MSI = 1,
- VMCI_INTR_TYPE_MSIX = 2,
-};
-
/* Maximum MSI/MSI-X interrupt vectors in the device. */
#define VMCI_MAX_INTRS 2

--
2.1.4