openwrt/target/linux/layerscape/patches-5.4/821-vfio-0006-vfio-fsl-mc-A...

194 lines
4.7 KiB
Diff

From 9ea8e954812efc4fc9b27e553019295d4dcd0407 Mon Sep 17 00:00:00 2001
From: Diana Craciun <diana.craciun@nxp.com>
Date: Tue, 15 Oct 2019 11:22:26 +0300
Subject: [PATCH] vfio/fsl-mc: Added lock support in preparation for interrupt
handling
All the devices in a DPRC share the same pool of interrupts.
Because of this the access to the pool of interrupts must be
protected with a lock. Extend the current lock implementation
to have a lock per DPRC.
Signed-off-by: Diana Craciun <diana.craciun@nxp.com>
---
drivers/vfio/fsl-mc/vfio_fsl_mc.c | 90 ++++++++++++++++++++++++++++---
drivers/vfio/fsl-mc/vfio_fsl_mc_private.h | 7 ++-
2 files changed, 89 insertions(+), 8 deletions(-)
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
@@ -15,6 +15,75 @@
#include "vfio_fsl_mc_private.h"
+static DEFINE_MUTEX(reflck_lock);
+
+static void vfio_fsl_mc_reflck_get(struct vfio_fsl_mc_reflck *reflck)
+{
+ kref_get(&reflck->kref);
+}
+
+static void vfio_fsl_mc_reflck_release(struct kref *kref)
+{
+ struct vfio_fsl_mc_reflck *reflck = container_of(kref,
+ struct vfio_fsl_mc_reflck,
+ kref);
+
+ kfree(reflck);
+ mutex_unlock(&reflck_lock);
+}
+
+static void vfio_fsl_mc_reflck_put(struct vfio_fsl_mc_reflck *reflck)
+{
+ kref_put_mutex(&reflck->kref, vfio_fsl_mc_reflck_release, &reflck_lock);
+}
+
+static struct vfio_fsl_mc_reflck *vfio_fsl_mc_reflck_alloc(void)
+{
+ struct vfio_fsl_mc_reflck *reflck;
+
+ reflck = kzalloc(sizeof(*reflck), GFP_KERNEL);
+ if (!reflck)
+ return ERR_PTR(-ENOMEM);
+
+ kref_init(&reflck->kref);
+ mutex_init(&reflck->lock);
+
+ return reflck;
+}
+
+static int vfio_fsl_mc_reflck_attach(struct vfio_fsl_mc_device *vdev)
+{
+ int ret = 0;
+
+ mutex_lock(&reflck_lock);
+ if (is_fsl_mc_bus_dprc(vdev->mc_dev)) {
+ vdev->reflck = vfio_fsl_mc_reflck_alloc();
+ } else {
+ struct device *mc_cont_dev = vdev->mc_dev->dev.parent;
+ struct vfio_device *device;
+ struct vfio_fsl_mc_device *cont_vdev;
+
+ device = vfio_device_get_from_dev(mc_cont_dev);
+ if (!device) {
+ ret = -ENODEV;
+ goto unlock;
+ }
+
+ cont_vdev = vfio_device_data(device);
+ if (!cont_vdev->reflck) {
+ vfio_device_put(device);
+ ret = -ENODEV;
+ goto unlock;
+ }
+ vfio_fsl_mc_reflck_get(cont_vdev->reflck);
+ vdev->reflck = cont_vdev->reflck;
+ vfio_device_put(device);
+ }
+
+unlock:
+ mutex_unlock(&reflck_lock);
+ return ret;
+}
static int vfio_fsl_mc_regions_init(struct vfio_fsl_mc_device *vdev)
{
@@ -55,7 +124,7 @@ static int vfio_fsl_mc_open(void *device
if (!try_module_get(THIS_MODULE))
return -ENODEV;
- mutex_lock(&vdev->driver_lock);
+ mutex_lock(&vdev->reflck->lock);
if (!vdev->refcnt) {
ret = vfio_fsl_mc_regions_init(vdev);
if (ret)
@@ -63,11 +132,11 @@ static int vfio_fsl_mc_open(void *device
}
vdev->refcnt++;
- mutex_unlock(&vdev->driver_lock);
+ mutex_unlock(&vdev->reflck->lock);
return 0;
err_reg_init:
- mutex_unlock(&vdev->driver_lock);
+ mutex_unlock(&vdev->reflck->lock);
module_put(THIS_MODULE);
return ret;
}
@@ -76,12 +145,12 @@ static void vfio_fsl_mc_release(void *de
{
struct vfio_fsl_mc_device *vdev = device_data;
- mutex_lock(&vdev->driver_lock);
+ mutex_lock(&vdev->reflck->lock);
if (!(--vdev->refcnt))
vfio_fsl_mc_regions_cleanup(vdev);
- mutex_unlock(&vdev->driver_lock);
+ mutex_unlock(&vdev->reflck->lock);
module_put(THIS_MODULE);
}
@@ -180,7 +249,6 @@ static int vfio_fsl_mc_mmap_mmio(struct
return -EINVAL;
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
-
vma->vm_pgoff = (region.addr >> PAGE_SHIFT) + pgoff;
return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
@@ -335,12 +403,18 @@ static int vfio_fsl_mc_probe(struct fsl_
return ret;
}
+ ret = vfio_fsl_mc_reflck_attach(vdev);
+ if (ret) {
+ vfio_iommu_group_put(group, dev);
+ return ret;
+ }
+
ret = vfio_fsl_mc_init_device(vdev);
if (ret) {
+ vfio_fsl_mc_reflck_put(vdev->reflck);
vfio_iommu_group_put(group, dev);
return ret;
}
- mutex_init(&vdev->driver_lock);
return ret;
}
@@ -374,6 +448,8 @@ static int vfio_fsl_mc_remove(struct fsl
if (!vdev)
return -EINVAL;
+ vfio_fsl_mc_reflck_put(vdev->reflck);
+
if (is_fsl_mc_bus_dprc(mc_dev))
vfio_fsl_mc_cleanup_dprc(vdev->mc_dev);
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
@@ -15,6 +15,11 @@
#define VFIO_FSL_MC_INDEX_TO_OFFSET(index) \
((u64)(index) << VFIO_FSL_MC_OFFSET_SHIFT)
+struct vfio_fsl_mc_reflck {
+ struct kref kref;
+ struct mutex lock;
+};
+
struct vfio_fsl_mc_region {
u32 flags;
u32 type;
@@ -27,7 +32,7 @@ struct vfio_fsl_mc_device {
int refcnt;
u32 num_regions;
struct vfio_fsl_mc_region *regions;
- struct mutex driver_lock;
+ struct vfio_fsl_mc_reflck *reflck;
};
#endif /* VFIO_PCI_PRIVATE_H */