There's only one caller that checks its return value with a WARN_ON_ONCE, while all other callers do not check return value at all. So simplify the API to return void by embedding similar WARN_ON_ONCEs. Suggested-by: Christoph Hellwig <hch@xxxxxxxxxxxxx> Signed-off-by: Nicolin Chen <nicolinc@xxxxxxxxxx> --- .../driver-api/vfio-mediated-device.rst | 2 +- drivers/gpu/drm/i915/gvt/kvmgt.c | 5 +--- drivers/vfio/vfio.c | 24 ++++++++----------- drivers/vfio/vfio.h | 2 +- drivers/vfio/vfio_iommu_type1.c | 16 ++++++------- include/linux/vfio.h | 4 ++-- 6 files changed, 23 insertions(+), 30 deletions(-) diff --git a/Documentation/driver-api/vfio-mediated-device.rst b/Documentation/driver-api/vfio-mediated-device.rst index 1c57815619fd..b0fdf76b339a 100644 --- a/Documentation/driver-api/vfio-mediated-device.rst +++ b/Documentation/driver-api/vfio-mediated-device.rst @@ -265,7 +265,7 @@ driver:: int vfio_pin_pages(struct vfio_device *device, unsigned long *user_pfn, int npage, int prot, unsigned long *phys_pfn); - int vfio_unpin_pages(struct vfio_device *device, unsigned long *user_pfn, + void vfio_unpin_pages(struct vfio_device *device, unsigned long *user_pfn, int npage); These functions call back into the back-end IOMMU module by using the pin_pages diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c index e2f6c56ab342..8c67c9aba82d 100644 --- a/drivers/gpu/drm/i915/gvt/kvmgt.c +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c @@ -231,18 +231,15 @@ static void intel_gvt_cleanup_vgpu_type_groups(struct intel_gvt *gvt) static void gvt_unpin_guest_page(struct intel_vgpu *vgpu, unsigned long gfn, unsigned long size) { - struct drm_i915_private *i915 = vgpu->gvt->gt->i915; int total_pages; int npage; - int ret; total_pages = roundup(size, PAGE_SIZE) / PAGE_SIZE; for (npage = 0; npage < total_pages; npage++) { unsigned long cur_gfn = gfn + npage; - ret = vfio_unpin_pages(&vgpu->vfio_device, &cur_gfn, 1); - drm_WARN_ON(&i915->drm, ret != 1); + vfio_unpin_pages(&vgpu->vfio_device, &cur_gfn, 1); } } diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index 61e71c1154be..01f45ec70a3d 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -1959,31 +1959,27 @@ EXPORT_SYMBOL(vfio_pin_pages); * PFNs should not be greater than VFIO_PIN_PAGES_MAX_ENTRIES. * @npage [in] : count of elements in user_pfn array. This count should not * be greater than VFIO_PIN_PAGES_MAX_ENTRIES. - * Return error or number of pages unpinned. */ -int vfio_unpin_pages(struct vfio_device *device, unsigned long *user_pfn, - int npage) +void vfio_unpin_pages(struct vfio_device *device, unsigned long *user_pfn, + int npage) { struct vfio_container *container; struct vfio_iommu_driver *driver; - int ret; - if (!user_pfn || !npage || !vfio_assert_device_open(device)) - return -EINVAL; + if (WARN_ON_ONCE(!user_pfn || !npage || !vfio_assert_device_open(device))) + return; - if (npage > VFIO_PIN_PAGES_MAX_ENTRIES) - return -E2BIG; + if (WARN_ON_ONCE(npage > VFIO_PIN_PAGES_MAX_ENTRIES)) + return; /* group->container cannot change while a vfio device is open */ container = device->group->container; driver = container->iommu_driver; - if (likely(driver && driver->ops->unpin_pages)) - ret = driver->ops->unpin_pages(container->iommu_data, user_pfn, - npage); - else - ret = -ENOTTY; - return ret; + if (WARN_ON_ONCE(unlikely(!driver || !driver->ops->unpin_pages))) + return; + + driver->ops->unpin_pages(container->iommu_data, user_pfn, npage); } EXPORT_SYMBOL(vfio_unpin_pages); diff --git a/drivers/vfio/vfio.h b/drivers/vfio/vfio.h index a67130221151..bef4edf58138 100644 --- a/drivers/vfio/vfio.h +++ b/drivers/vfio/vfio.h @@ -53,7 +53,7 @@ struct vfio_iommu_driver_ops { unsigned long *user_pfn, int npage, int prot, unsigned long *phys_pfn); - int (*unpin_pages)(void *iommu_data, + void (*unpin_pages)(void *iommu_data, unsigned long *user_pfn, int npage); int (*register_notifier)(void *iommu_data, unsigned long *events, diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index c13b9290e357..08613edaf722 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -948,20 +948,19 @@ static int vfio_iommu_type1_pin_pages(void *iommu_data, return ret; } -static int vfio_iommu_type1_unpin_pages(void *iommu_data, - unsigned long *user_pfn, - int npage) +static void vfio_iommu_type1_unpin_pages(void *iommu_data, + unsigned long *user_pfn, int npage) { struct vfio_iommu *iommu = iommu_data; bool do_accounting; int i; - if (!iommu || !user_pfn || npage <= 0) - return -EINVAL; + if (WARN_ON_ONCE(!iommu || !user_pfn || npage <= 0)) + return; /* Supported for v2 version only */ - if (!iommu->v2) - return -EACCES; + if (WARN_ON_ONCE(!iommu->v2)) + return; mutex_lock(&iommu->lock); @@ -979,7 +978,8 @@ static int vfio_iommu_type1_unpin_pages(void *iommu_data, } mutex_unlock(&iommu->lock); - return i > 0 ? i : -EINVAL; + + WARN_ON_ONCE(i != npage); } static long vfio_sync_unpin(struct vfio_dma *dma, struct vfio_domain *domain, diff --git a/include/linux/vfio.h b/include/linux/vfio.h index 49580fa2073a..d0844ecdc961 100644 --- a/include/linux/vfio.h +++ b/include/linux/vfio.h @@ -149,8 +149,8 @@ bool vfio_file_has_dev(struct file *file, struct vfio_device *device); int vfio_pin_pages(struct vfio_device *device, unsigned long *user_pfn, int npage, int prot, unsigned long *phys_pfn); -int vfio_unpin_pages(struct vfio_device *device, unsigned long *user_pfn, - int npage); +void vfio_unpin_pages(struct vfio_device *device, unsigned long *user_pfn, + int npage); int vfio_dma_rw(struct vfio_device *device, dma_addr_t user_iova, void *data, size_t len, bool write); -- 2.17.1