2020-07-06 15:44:31

by Diana Madalina Craciun

[permalink] [raw]
Subject: [PATCH v3 8/9] vfio/fsl-mc: trigger an interrupt via eventfd

This patch allows to set an eventfd for fsl-mc device interrupts
and also to trigger the interrupt eventfd from userspace for testing.

All fsl-mc device interrupts are MSIs. The MSIs are allocated from
the MSI domain only once per DPRC and used by all the DPAA2 objects.
The interrupts are managed by the DPRC in a pool of interrupts. Each
device requests interrupts from this pool. The pool is allocated
when the first virtual device is setting the interrupts.
The pool of interrupts is protected by a lock.

The DPRC has an interrupt of its own which indicates if the DPRC
contents have changed. However, currently, the contents of a DPRC
assigned to the guest cannot be changed at runtime, so this interrupt
is not configured.

Signed-off-by: Bharat Bhushan <[email protected]>
Signed-off-by: Diana Craciun <[email protected]>
---
drivers/vfio/fsl-mc/vfio_fsl_mc.c | 18 ++-
drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c | 160 +++++++++++++++++++++-
drivers/vfio/fsl-mc/vfio_fsl_mc_private.h | 11 +-
3 files changed, 186 insertions(+), 3 deletions(-)

diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
index 2ce17d297145..0c2d4f11dc43 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
@@ -146,12 +146,28 @@ static int vfio_fsl_mc_open(void *device_data)
static void vfio_fsl_mc_release(void *device_data)
{
struct vfio_fsl_mc_device *vdev = device_data;
+ int ret;

mutex_lock(&vdev->reflck->lock);

- if (!(--vdev->refcnt))
+ if (!(--vdev->refcnt)) {
+ struct fsl_mc_device *mc_dev = vdev->mc_dev;
+ struct device *cont_dev = fsl_mc_cont_dev(&mc_dev->dev);
+ struct fsl_mc_device *mc_cont = to_fsl_mc_device(cont_dev);
+
vfio_fsl_mc_regions_cleanup(vdev);

+ /* reset the device before cleaning up the interrupts */
+ ret = dprc_reset_container(mc_cont->mc_io, 0,
+ mc_cont->mc_handle,
+ mc_cont->obj_desc.id,
+ DPRC_RESET_OPTION_NON_RECURSIVE);
+
+ vfio_fsl_mc_irqs_cleanup(vdev);
+
+ fsl_mc_cleanup_irq_pool(mc_cont);
+ }
+
mutex_unlock(&vdev->reflck->lock);

module_put(THIS_MODULE);
diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c b/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c
index 058aa97aa54a..409f3507fcf3 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c
@@ -29,12 +29,149 @@ static int vfio_fsl_mc_irq_unmask(struct vfio_fsl_mc_device *vdev,
return -EINVAL;
}

+int vfio_fsl_mc_irqs_allocate(struct vfio_fsl_mc_device *vdev)
+{
+ struct fsl_mc_device *mc_dev = vdev->mc_dev;
+ struct vfio_fsl_mc_irq *mc_irq;
+ int irq_count;
+ int ret, i;
+
+ /* Device does not support any interrupt */
+ if (mc_dev->obj_desc.irq_count == 0)
+ return 0;
+
+ /* interrupts were already allocated for this device */
+ if (vdev->mc_irqs)
+ return 0;
+
+ irq_count = mc_dev->obj_desc.irq_count;
+
+ mc_irq = kcalloc(irq_count, sizeof(*mc_irq), GFP_KERNEL);
+ if (!mc_irq)
+ return -ENOMEM;
+
+ /* Allocate IRQs */
+ ret = fsl_mc_allocate_irqs(mc_dev);
+ if (ret) {
+ kfree(mc_irq);
+ return ret;
+ }
+
+ for (i = 0; i < irq_count; i++) {
+ mc_irq[i].count = 1;
+ mc_irq[i].flags = VFIO_IRQ_INFO_EVENTFD;
+ }
+
+ vdev->mc_irqs = mc_irq;
+
+ return 0;
+}
+
+static irqreturn_t vfio_fsl_mc_irq_handler(int irq_num, void *arg)
+{
+ struct vfio_fsl_mc_irq *mc_irq = (struct vfio_fsl_mc_irq *)arg;
+
+ eventfd_signal(mc_irq->trigger, 1);
+ return IRQ_HANDLED;
+}
+
+static int vfio_set_trigger(struct vfio_fsl_mc_device *vdev,
+ int index, int fd)
+{
+ struct vfio_fsl_mc_irq *irq = &vdev->mc_irqs[index];
+ struct eventfd_ctx *trigger;
+ int hwirq;
+ int ret;
+
+ hwirq = vdev->mc_dev->irqs[index]->msi_desc->irq;
+ if (irq->trigger) {
+ free_irq(hwirq, irq);
+ kfree(irq->name);
+ eventfd_ctx_put(irq->trigger);
+ irq->trigger = NULL;
+ }
+
+ if (fd < 0) /* Disable only */
+ return 0;
+
+ irq->name = kasprintf(GFP_KERNEL, "vfio-irq[%d](%s)",
+ hwirq, dev_name(&vdev->mc_dev->dev));
+ if (!irq->name)
+ return -ENOMEM;
+
+ trigger = eventfd_ctx_fdget(fd);
+ if (IS_ERR(trigger)) {
+ kfree(irq->name);
+ return PTR_ERR(trigger);
+ }
+
+ irq->trigger = trigger;
+
+ ret = request_irq(hwirq, vfio_fsl_mc_irq_handler, 0,
+ irq->name, irq);
+ if (ret) {
+ kfree(irq->name);
+ eventfd_ctx_put(trigger);
+ irq->trigger = NULL;
+ return ret;
+ }
+
+ return 0;
+}
+
static int vfio_fsl_mc_set_irq_trigger(struct vfio_fsl_mc_device *vdev,
unsigned int index, unsigned int start,
unsigned int count, u32 flags,
void *data)
{
- return -EINVAL;
+ struct fsl_mc_device *mc_dev = vdev->mc_dev;
+ int ret, hwirq;
+ struct vfio_fsl_mc_irq *irq;
+ struct device *cont_dev = fsl_mc_cont_dev(&mc_dev->dev);
+ struct fsl_mc_device *mc_cont = to_fsl_mc_device(cont_dev);
+
+ if (start != 0 || count != 1)
+ return -EINVAL;
+
+ mutex_lock(&vdev->reflck->lock);
+ ret = fsl_mc_populate_irq_pool(mc_cont,
+ FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
+ if (ret)
+ goto unlock;
+
+ ret = vfio_fsl_mc_irqs_allocate(vdev);
+ if (ret)
+ goto unlock;
+ mutex_unlock(&vdev->reflck->lock);
+
+ if (!count && (flags & VFIO_IRQ_SET_DATA_NONE))
+ return vfio_set_trigger(vdev, index, -1);
+
+ if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
+ s32 fd = *(s32 *)data;
+
+ return vfio_set_trigger(vdev, index, fd);
+ }
+
+ hwirq = vdev->mc_dev->irqs[index]->msi_desc->irq;
+
+ irq = &vdev->mc_irqs[index];
+
+ if (flags & VFIO_IRQ_SET_DATA_NONE) {
+ vfio_fsl_mc_irq_handler(hwirq, irq);
+
+ } else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
+ u8 trigger = *(u8 *)data;
+
+ if (trigger)
+ vfio_fsl_mc_irq_handler(hwirq, irq);
+ }
+
+ return 0;
+
+unlock:
+ mutex_unlock(&vdev->reflck->lock);
+ return ret;
}

int vfio_fsl_mc_set_irqs_ioctl(struct vfio_fsl_mc_device *vdev,
@@ -61,3 +198,24 @@ int vfio_fsl_mc_set_irqs_ioctl(struct vfio_fsl_mc_device *vdev,

return ret;
}
+
+/* Free All IRQs for the given MC object */
+void vfio_fsl_mc_irqs_cleanup(struct vfio_fsl_mc_device *vdev)
+{
+ struct fsl_mc_device *mc_dev = vdev->mc_dev;
+ int irq_count = mc_dev->obj_desc.irq_count;
+ int i;
+
+ /* Device does not support any interrupt or the interrupts
+ * were not configured
+ */
+ if (mc_dev->obj_desc.irq_count == 0 || !vdev->mc_irqs)
+ return;
+
+ for (i = 0; i < irq_count; i++)
+ vfio_set_trigger(vdev, i, -1);
+
+ fsl_mc_free_irqs(mc_dev);
+ kfree(vdev->mc_irqs);
+ vdev->mc_irqs = NULL;
+}
diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
index dd94be84a3d0..1f9b518c520d 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
@@ -15,6 +15,13 @@
#define VFIO_FSL_MC_INDEX_TO_OFFSET(index) \
((u64)(index) << VFIO_FSL_MC_OFFSET_SHIFT)

+struct vfio_fsl_mc_irq {
+ u32 flags;
+ u32 count;
+ struct eventfd_ctx *trigger;
+ char *name;
+};
+
struct vfio_fsl_mc_reflck {
struct kref kref;
struct mutex lock;
@@ -34,7 +41,7 @@ struct vfio_fsl_mc_device {
u32 num_regions;
struct vfio_fsl_mc_region *regions;
struct vfio_fsl_mc_reflck *reflck;
-
+ struct vfio_fsl_mc_irq *mc_irqs;
};

extern int vfio_fsl_mc_set_irqs_ioctl(struct vfio_fsl_mc_device *vdev,
@@ -42,4 +49,6 @@ extern int vfio_fsl_mc_set_irqs_ioctl(struct vfio_fsl_mc_device *vdev,
unsigned int start, unsigned int count,
void *data);

+void vfio_fsl_mc_irqs_cleanup(struct vfio_fsl_mc_device *vdev);
+
#endif /* VFIO_FSL_MC_PRIVATE_H */
--
2.17.1


2020-07-06 19:03:34

by kernel test robot

[permalink] [raw]
Subject: Re: [PATCH v3 8/9] vfio/fsl-mc: trigger an interrupt via eventfd

Hi Diana,

I love your patch! Perhaps something to improve:

[auto build test WARNING on vfio/next]
[also build test WARNING on linux/master linus/master v5.8-rc4 next-20200706]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use as documented in
https://git-scm.com/docs/git-format-patch]

url: https://github.com/0day-ci/linux/commits/Diana-Craciun/vfio-fsl-mc-VFIO-support-for-FSL-MC-devices/20200706-234519
base: https://github.com/awilliam/linux-vfio.git next
config: x86_64-allyesconfig (attached as .config)
compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project a378c0449507e00e96534ff9ce9034e185425182)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install x86_64 cross compiling tool for clang build
# apt-get install binutils-x86-64-linux-gnu
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <[email protected]>

All warnings (new ones prefixed by >>):

>> drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c:32:5: warning: no previous prototype for function 'vfio_fsl_mc_irqs_allocate' [-Wmissing-prototypes]
int vfio_fsl_mc_irqs_allocate(struct vfio_fsl_mc_device *vdev)
^
drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c:32:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
int vfio_fsl_mc_irqs_allocate(struct vfio_fsl_mc_device *vdev)
^
static
drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c:137:8: error: implicit declaration of function 'fsl_mc_populate_irq_pool' [-Werror,-Wimplicit-function-declaration]
ret = fsl_mc_populate_irq_pool(mc_cont,
^
drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c:138:4: error: use of undeclared identifier 'FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS'
FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
^
1 warning and 2 errors generated.

vim +/vfio_fsl_mc_irqs_allocate +32 drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c

31
> 32 int vfio_fsl_mc_irqs_allocate(struct vfio_fsl_mc_device *vdev)
33 {
34 struct fsl_mc_device *mc_dev = vdev->mc_dev;
35 struct vfio_fsl_mc_irq *mc_irq;
36 int irq_count;
37 int ret, i;
38
39 /* Device does not support any interrupt */
40 if (mc_dev->obj_desc.irq_count == 0)
41 return 0;
42
43 /* interrupts were already allocated for this device */
44 if (vdev->mc_irqs)
45 return 0;
46
47 irq_count = mc_dev->obj_desc.irq_count;
48
49 mc_irq = kcalloc(irq_count, sizeof(*mc_irq), GFP_KERNEL);
50 if (!mc_irq)
51 return -ENOMEM;
52
53 /* Allocate IRQs */
54 ret = fsl_mc_allocate_irqs(mc_dev);
55 if (ret) {
56 kfree(mc_irq);
57 return ret;
58 }
59
60 for (i = 0; i < irq_count; i++) {
61 mc_irq[i].count = 1;
62 mc_irq[i].flags = VFIO_IRQ_INFO_EVENTFD;
63 }
64
65 vdev->mc_irqs = mc_irq;
66
67 return 0;
68 }
69

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/[email protected]


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