Register dummy interrupt handlers for DMA datagrams in preparation for
DMA datagram receive operations.
Reviewed-by: Vishnu Dasa <vdasa@xxxxxxxxxx>
Signed-off-by: Jorgen Hansen <jhansen@xxxxxxxxxx>
---
drivers/misc/vmw_vmci/vmci_guest.c | 42 +++++++++++++++++++++++++++---
include/linux/vmw_vmci_defs.h | 14 ++++++++--
2 files changed, 51 insertions(+), 5 deletions(-)
diff --git a/drivers/misc/vmw_vmci/vmci_guest.c b/drivers/misc/vmw_vmci/vmci_guest.c
index 808680dc0820..0920fbc6b64f 100644
--- a/drivers/misc/vmw_vmci/vmci_guest.c
+++ b/drivers/misc/vmw_vmci/vmci_guest.c
@@ -414,6 +414,9 @@ static irqreturn_t vmci_interrupt(int irq, void *_dev)
icr &= ~VMCI_ICR_NOTIFICATION;
}
+ if (icr & VMCI_ICR_DMA_DATAGRAM)
+ icr &= ~VMCI_ICR_DMA_DATAGRAM;
+
if (icr != 0)
dev_warn(dev->dev,
"Ignoring unknown interrupt cause (%d)\n",
@@ -438,6 +441,16 @@ static irqreturn_t vmci_interrupt_bm(int irq, void *_dev)
return IRQ_HANDLED;
}
+/*
+ * Interrupt handler for MSI-X interrupt vector VMCI_INTR_DMA_DATAGRAM,
+ * which is for the completion of a DMA datagram send or receive operation.
+ * Will only get called if we are using MSI-X with exclusive vectors.
+ */
+static irqreturn_t vmci_interrupt_dma_datagram(int irq, void *_dev)
+{
+ return IRQ_HANDLED;
+}
+
/*
* Most of the initialization at module load time is done here.
*/
@@ -447,6 +460,7 @@ static int vmci_guest_probe_device(struct pci_dev *pdev,
struct vmci_guest_device *vmci_dev;
void __iomem *iobase = NULL;
void __iomem *mmio_base = NULL;
+ unsigned int num_irq_vectors;
unsigned int capabilities;
unsigned int caps_in_use;
unsigned long cmd;
@@ -635,8 +649,12 @@ static int vmci_guest_probe_device(struct pci_dev *pdev,
* Enable interrupts. Try MSI-X first, then MSI, and then fallback on
* legacy interrupts.
*/
- error = pci_alloc_irq_vectors(pdev, VMCI_MAX_INTRS, VMCI_MAX_INTRS,
- PCI_IRQ_MSIX);
+ if (vmci_dev->mmio_base != NULL)
+ num_irq_vectors = VMCI_MAX_INTRS;
+ else
+ num_irq_vectors = VMCI_MAX_INTRS_NOTIFICATION;
+ error = pci_alloc_irq_vectors(pdev, num_irq_vectors, num_irq_vectors,
+ PCI_IRQ_MSIX);
if (error < 0) {
error = pci_alloc_irq_vectors(pdev, 1, 1,
PCI_IRQ_MSIX | PCI_IRQ_MSI | PCI_IRQ_LEGACY);
@@ -674,6 +692,17 @@ static int vmci_guest_probe_device(struct pci_dev *pdev,
pci_irq_vector(pdev, 1), error);
goto err_free_irq;
}
+ if (caps_in_use & VMCI_CAPS_DMA_DATAGRAM) {
+ error = request_irq(pci_irq_vector(pdev, 2),
+ vmci_interrupt_dma_datagram,
+ 0, KBUILD_MODNAME, vmci_dev);
+ if (error) {
+ dev_err(&pdev->dev,
+ "Failed to allocate irq %u: %d\n",
+ pci_irq_vector(pdev, 2), error);
+ goto err_free_bm_irq;
+ }
+ }
}
dev_dbg(&pdev->dev, "Registered device\n");
@@ -684,6 +713,8 @@ static int vmci_guest_probe_device(struct pci_dev *pdev,
cmd = VMCI_IMR_DATAGRAM;
if (caps_in_use & VMCI_CAPS_NOTIFICATIONS)
cmd |= VMCI_IMR_NOTIFICATION;
+ if (caps_in_use & VMCI_CAPS_DMA_DATAGRAM)
+ cmd |= VMCI_IMR_DMA_DATAGRAM;
vmci_write_reg(vmci_dev, cmd, VMCI_IMR_ADDR);
/* Enable interrupts. */
@@ -694,6 +725,8 @@ static int vmci_guest_probe_device(struct pci_dev *pdev,
vmci_call_vsock_callback(false);
return 0;
+err_free_bm_irq:
+ free_irq(pci_irq_vector(pdev, 1), vmci_dev);
err_free_irq:
free_irq(pci_irq_vector(pdev, 0), vmci_dev);
tasklet_kill(&vmci_dev->datagram_tasklet);
@@ -759,8 +792,11 @@ 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.
*/
- if (vmci_dev->exclusive_vectors)
+ if (vmci_dev->exclusive_vectors) {
free_irq(pci_irq_vector(pdev, 1), vmci_dev);
+ if (vmci_dev->mmio_base != NULL)
+ free_irq(pci_irq_vector(pdev, 2), vmci_dev);
+ }
free_irq(pci_irq_vector(pdev, 0), vmci_dev);
pci_free_irq_vectors(pdev);
diff --git a/include/linux/vmw_vmci_defs.h b/include/linux/vmw_vmci_defs.h
index 4167779469fd..2b70c024dacb 100644
--- a/include/linux/vmw_vmci_defs.h
+++ b/include/linux/vmw_vmci_defs.h
@@ -45,13 +45,22 @@
/* Interrupt Cause register bits. */
#define VMCI_ICR_DATAGRAM BIT(0)
#define VMCI_ICR_NOTIFICATION BIT(1)
+#define VMCI_ICR_DMA_DATAGRAM BIT(2)
/* Interrupt Mask register bits. */
#define VMCI_IMR_DATAGRAM BIT(0)
#define VMCI_IMR_NOTIFICATION BIT(1)
+#define VMCI_IMR_DMA_DATAGRAM BIT(2)
-/* Maximum MSI/MSI-X interrupt vectors in the device. */
-#define VMCI_MAX_INTRS 2
+/*
+ * Maximum MSI/MSI-X interrupt vectors in the device.
+ * If VMCI_CAPS_DMA_DATAGRAM is supported by the device,
+ * VMCI_MAX_INTRS_DMA_DATAGRAM vectors are available,
+ * otherwise only VMCI_MAX_INTRS_NOTIFICATION.
+ */
+#define VMCI_MAX_INTRS_NOTIFICATION 2
+#define VMCI_MAX_INTRS_DMA_DATAGRAM 3
+#define VMCI_MAX_INTRS VMCI_MAX_INTRS_DMA_DATAGRAM
/*
* Supported interrupt vectors. There is one for each ICR value above,
@@ -60,6 +69,7 @@
enum {
VMCI_INTR_DATAGRAM = 0,
VMCI_INTR_NOTIFICATION = 1,
+ VMCI_INTR_DMA_DATAGRAM = 2,
};
/*
--
2.25.1
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