[PATCH v9 10/12] pci_endpoint_test: Add 2 ioctl commands

From: Gustavo Pimentel
Date: Mon Jul 09 2018 - 13:44:01 EST


Add MSI-X support and update driver documentation accordingly.

Add 2 new IOCTL commands:
- Allow to reconfigure driver IRQ type in runtime.
- Allow to retrieve current driver IRQ type configured.

Signed-off-by: Gustavo Pimentel <gustavo.pimentel@xxxxxxxxxxxx>
---
Change v2->v3:
- New patch file created base on the previous patch
"misc: pci_endpoint_test: Add MSI-X support" patch file following
Kishon's suggestion.
Change v3->v4:
- Rebased to Lorenzo's master branch v4.18-rc1.
Change v4->v5:
- Nothing changed, just to follow the patch set version.
Change v5->v6:
- Moved PCITEST_SET_IRQTYPE and PCITEST_GET_IRQTYPE ioctl entries
from patch #10 to here.
- Increased ioctl parameters range associated to
drivers/misc/pci_endpoint_test.c driver.
Change v6->v7:
- irq_type variable update just before returning the function.
Change v7->v8:
- Re-sending the patch series.
Change v8->v9:
- Added a extra parameter to pci_endpoint_test_alloc_irq_vectors,
that specifies which irq type should be allocated.

Documentation/ioctl/ioctl-number.txt | 2 +-
Documentation/misc-devices/pci-endpoint-test.txt | 3 +
drivers/misc/pci_endpoint_test.c | 176 +++++++++++++++++------
include/uapi/linux/pcitest.h | 2 +
4 files changed, 136 insertions(+), 47 deletions(-)

diff --git a/Documentation/ioctl/ioctl-number.txt b/Documentation/ioctl/ioctl-number.txt
index 65259d4..c15c4f3 100644
--- a/Documentation/ioctl/ioctl-number.txt
+++ b/Documentation/ioctl/ioctl-number.txt
@@ -166,7 +166,7 @@ Code Seq#(hex) Include File Comments
'P' all linux/soundcard.h conflict!
'P' 60-6F sound/sscape_ioctl.h conflict!
'P' 00-0F drivers/usb/class/usblp.c conflict!
-'P' 01-07 drivers/misc/pci_endpoint_test.c conflict!
+'P' 01-09 drivers/misc/pci_endpoint_test.c conflict!
'Q' all linux/soundcard.h
'R' 00-1F linux/random.h conflict!
'R' 01 linux/rfkill.h conflict!
diff --git a/Documentation/misc-devices/pci-endpoint-test.txt b/Documentation/misc-devices/pci-endpoint-test.txt
index fdfa0f6..58ccca4 100644
--- a/Documentation/misc-devices/pci-endpoint-test.txt
+++ b/Documentation/misc-devices/pci-endpoint-test.txt
@@ -28,6 +28,9 @@ ioctl
to be tested should be passed as argument.
PCITEST_MSIX: Tests message signalled interrupts. The MSI-X number
to be tested should be passed as argument.
+ PCITEST_SET_IRQTYPE: Changes driver IRQ type configuration. The IRQ type
+ should be passed as argument (0: Legacy, 1:MSI, 2:MSI-X).
+ PCITEST_GET_IRQTYPE: Gets driver IRQ type configuration.
PCITEST_WRITE: Perform write tests. The size of the buffer should be passed
as argument.
PCITEST_READ: Perform read tests. The size of the buffer should be passed
diff --git a/drivers/misc/pci_endpoint_test.c b/drivers/misc/pci_endpoint_test.c
index f4fef10..ce4b79a 100644
--- a/drivers/misc/pci_endpoint_test.c
+++ b/drivers/misc/pci_endpoint_test.c
@@ -157,6 +157,88 @@ static irqreturn_t pci_endpoint_test_irqhandler(int irq, void *dev_id)
return IRQ_HANDLED;
}

+static void pci_endpoint_test_free_irq_vectors(struct pci_endpoint_test *test)
+{
+ int i;
+ struct pci_dev *pdev = test->pdev;
+ struct device *dev = &pdev->dev;
+
+ for (i = 0; i < test->num_irqs; i++)
+ devm_free_irq(dev, pci_irq_vector(pdev, i), test);
+
+ test->num_irqs = 0;
+}
+
+static bool pci_endpoint_test_alloc_irq_vectors(struct pci_endpoint_test *test,
+ int type)
+{
+ int irq = -1;
+ struct pci_dev *pdev = test->pdev;
+ struct device *dev = &pdev->dev;
+ bool res = true;
+
+ switch (type) {
+ case IRQ_TYPE_LEGACY:
+ irq = 0;
+ break;
+ case IRQ_TYPE_MSI:
+ irq = pci_alloc_irq_vectors(pdev, 1, 32, PCI_IRQ_MSI);
+ if (irq < 0)
+ dev_err(dev, "Failed to get MSI interrupts\n");
+ break;
+ case IRQ_TYPE_MSIX:
+ irq = pci_alloc_irq_vectors(pdev, 1, 2048, PCI_IRQ_MSIX);
+ if (irq < 0)
+ dev_err(dev, "Failed to get MSI-X interrupts\n");
+ break;
+ default:
+ dev_err(dev, "Invalid IRQ type selected\n");
+ }
+
+ if (irq < 0) {
+ irq = 0;
+ res = false;
+ }
+ test->num_irqs = irq;
+
+ return res;
+}
+
+static void pci_endpoint_test_release_irq(struct pci_endpoint_test *test)
+{
+ struct pci_dev *pdev = test->pdev;
+
+ pci_disable_msi(pdev);
+ pci_disable_msix(pdev);
+}
+
+static bool pci_endpoint_test_request_irq(struct pci_endpoint_test *test)
+{
+ int i;
+ int err;
+ struct pci_dev *pdev = test->pdev;
+ struct device *dev = &pdev->dev;
+
+ err = devm_request_irq(dev, pdev->irq, pci_endpoint_test_irqhandler,
+ IRQF_SHARED, DRV_MODULE_NAME, test);
+ if (err) {
+ dev_err(dev, "Failed to request IRQ %d\n", pdev->irq);
+ return false;
+ }
+
+ for (i = 1; i < test->num_irqs; i++) {
+ err = devm_request_irq(dev, pci_irq_vector(pdev, i),
+ pci_endpoint_test_irqhandler,
+ IRQF_SHARED, DRV_MODULE_NAME, test);
+ if (err)
+ dev_err(dev, "Failed to request IRQ %d for MSI%s %d\n",
+ pci_irq_vector(pdev, i),
+ irq_type == IRQ_TYPE_MSIX ? "-X" : "", i + 1);
+ }
+
+ return true;
+}
+
static bool pci_endpoint_test_bar(struct pci_endpoint_test *test,
enum pci_barno barno)
{
@@ -440,6 +522,38 @@ static bool pci_endpoint_test_read(struct pci_endpoint_test *test, size_t size)
return ret;
}

+static bool pci_endpoint_test_set_irq(struct pci_endpoint_test *test,
+ int req_irq_type)
+{
+ struct pci_dev *pdev = test->pdev;
+ struct device *dev = &pdev->dev;
+
+ if (req_irq_type < IRQ_TYPE_LEGACY || req_irq_type > IRQ_TYPE_MSIX) {
+ dev_err(dev, "Invalid IRQ type option\n");
+ return false;
+ }
+
+ if (irq_type == req_irq_type)
+ return true;
+
+ pci_endpoint_test_free_irq_vectors(test);
+ pci_endpoint_test_release_irq(test);
+
+ if (!pci_endpoint_test_alloc_irq_vectors(test, req_irq_type)) {
+ pci_endpoint_test_release_irq(test);
+ return false;
+ }
+
+ if (!pci_endpoint_test_request_irq(test)) {
+ pci_endpoint_test_release_irq(test);
+ return false;
+ }
+
+ irq_type = req_irq_type;
+
+ return true;
+}
+
static long pci_endpoint_test_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
@@ -471,6 +585,12 @@ static long pci_endpoint_test_ioctl(struct file *file, unsigned int cmd,
case PCITEST_COPY:
ret = pci_endpoint_test_copy(test, arg);
break;
+ case PCITEST_SET_IRQTYPE:
+ ret = pci_endpoint_test_set_irq(test, arg);
+ break;
+ case PCITEST_GET_IRQTYPE:
+ ret = irq_type;
+ break;
}

ret:
@@ -486,9 +606,7 @@ static const struct file_operations pci_endpoint_test_fops = {
static int pci_endpoint_test_probe(struct pci_dev *pdev,
const struct pci_device_id *ent)
{
- int i;
int err;
- int irq = 0;
int id;
char name[20];
enum pci_barno bar;
@@ -537,41 +655,11 @@ static int pci_endpoint_test_probe(struct pci_dev *pdev,

pci_set_master(pdev);

- switch (irq_type) {
- case IRQ_TYPE_LEGACY:
- break;
- case IRQ_TYPE_MSI:
- irq = pci_alloc_irq_vectors(pdev, 1, 32, PCI_IRQ_MSI);
- if (irq < 0)
- dev_err(dev, "Failed to get MSI interrupts\n");
- test->num_irqs = irq;
- break;
- case IRQ_TYPE_MSIX:
- irq = pci_alloc_irq_vectors(pdev, 1, 2048, PCI_IRQ_MSIX);
- if (irq < 0)
- dev_err(dev, "Failed to get MSI-X interrupts\n");
- test->num_irqs = irq;
- break;
- default:
- dev_err(dev, "Invalid IRQ type selected\n");
- }
-
- err = devm_request_irq(dev, pdev->irq, pci_endpoint_test_irqhandler,
- IRQF_SHARED, DRV_MODULE_NAME, test);
- if (err) {
- dev_err(dev, "Failed to request IRQ %d\n", pdev->irq);
- goto err_disable_msi;
- }
+ if (!pci_endpoint_test_alloc_irq_vectors(test, irq_type))
+ goto err_disable_irq;

- for (i = 1; i < irq; i++) {
- err = devm_request_irq(dev, pci_irq_vector(pdev, i),
- pci_endpoint_test_irqhandler,
- IRQF_SHARED, DRV_MODULE_NAME, test);
- if (err)
- dev_err(dev, "Failed to request IRQ %d for MSI%s %d\n",
- pci_irq_vector(pdev, i),
- irq_type == IRQ_TYPE_MSIX ? "-X" : "", i + 1);
- }
+ if (!pci_endpoint_test_request_irq(test))
+ goto err_disable_irq;

for (bar = BAR_0; bar <= BAR_5; bar++) {
if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
@@ -631,12 +719,10 @@ static int pci_endpoint_test_probe(struct pci_dev *pdev,
pci_iounmap(pdev, test->bar[bar]);
}

- for (i = 0; i < irq; i++)
- devm_free_irq(&pdev->dev, pci_irq_vector(pdev, i), test);
+ pci_endpoint_test_free_irq_vectors(test);

-err_disable_msi:
- pci_disable_msi(pdev);
- pci_disable_msix(pdev);
+err_disable_irq:
+ pci_endpoint_test_release_irq(test);
pci_release_regions(pdev);

err_disable_pdev:
@@ -648,7 +734,6 @@ static int pci_endpoint_test_probe(struct pci_dev *pdev,
static void pci_endpoint_test_remove(struct pci_dev *pdev)
{
int id;
- int i;
enum pci_barno bar;
struct pci_endpoint_test *test = pci_get_drvdata(pdev);
struct miscdevice *misc_device = &test->miscdev;
@@ -665,10 +750,9 @@ static void pci_endpoint_test_remove(struct pci_dev *pdev)
if (test->bar[bar])
pci_iounmap(pdev, test->bar[bar]);
}
- for (i = 0; i < test->num_irqs; i++)
- devm_free_irq(&pdev->dev, pci_irq_vector(pdev, i), test);
- pci_disable_msi(pdev);
- pci_disable_msix(pdev);
+ pci_endpoint_test_free_irq_vectors(test);
+
+ pci_endpoint_test_release_irq(test);
pci_release_regions(pdev);
pci_disable_device(pdev);
}
diff --git a/include/uapi/linux/pcitest.h b/include/uapi/linux/pcitest.h
index d746fb1..cbf422e 100644
--- a/include/uapi/linux/pcitest.h
+++ b/include/uapi/linux/pcitest.h
@@ -17,5 +17,7 @@
#define PCITEST_READ _IOW('P', 0x5, unsigned long)
#define PCITEST_COPY _IOW('P', 0x6, unsigned long)
#define PCITEST_MSIX _IOW('P', 0x7, int)
+#define PCITEST_SET_IRQTYPE _IOW('P', 0x8, int)
+#define PCITEST_GET_IRQTYPE _IO('P', 0x9)

#endif /* __UAPI_LINUX_PCITEST_H */
--
2.7.4