On 19/02/2024 09:30, Avihai Horon wrote:
> Hi Joao,
>
> On 12/02/2024 15:56, Joao Martins wrote:
>> External email: Use caution opening links or attachments
>>
>>
>> ioctl(iommufd, IOMMU_HWPT_GET_DIRTY_BITMAP, arg) is the UAPI
>> that fetches the bitmap that tells what was dirty in an IOVA
>> range.
>>
>> A single bitmap is allocated and used across all the hwpts
>> sharing an IOAS which is then used in log_sync() to set Qemu
>> global bitmaps.
>>
>> Signed-off-by: Joao Martins <joao.m.mart...@oracle.com>
>> ---
>> backends/iommufd.c | 24 ++++++++++++++++++++++++
>> backends/trace-events | 1 +
>> hw/vfio/iommufd.c | 30 ++++++++++++++++++++++++++++++
>> include/sysemu/iommufd.h | 3 +++
>> 4 files changed, 58 insertions(+)
>>
>> diff --git a/backends/iommufd.c b/backends/iommufd.c
>> index 954de61c2da0..dd676d493c37 100644
>> --- a/backends/iommufd.c
>> +++ b/backends/iommufd.c
>> @@ -259,6 +259,30 @@ int iommufd_backend_set_dirty_tracking(IOMMUFDBackend
>> *be, uint32_t hwpt_id,
>> return !ret ? 0 : -errno;
>> }
>>
>> +int iommufd_backend_get_dirty_bitmap(IOMMUFDBackend *be, uint32_t hwpt_id,
>> + uint64_t iova, ram_addr_t size,
>> + uint64_t page_size, uint64_t *data)
>> +{
>> + int ret;
>> + struct iommu_hwpt_get_dirty_bitmap get_dirty_bitmap = {
>> + .size = sizeof(get_dirty_bitmap),
>> + .hwpt_id = hwpt_id,
>> + .iova = iova, .length = size,
>> + .page_size = page_size, .data = (uintptr_t)data,
>
> Member per line for readability?
>
Yeap
>> + };
>> +
>> + ret = ioctl(be->fd, IOMMU_HWPT_GET_DIRTY_BITMAP, &get_dirty_bitmap);
>> + trace_iommufd_backend_get_dirty_bitmap(be->fd, hwpt_id, iova, size,
>> + page_size, ret);
>> + if (ret) {
>> + error_report("IOMMU_HWPT_GET_DIRTY_BITMAP (iova: 0x%"PRIx64
>> + " size: 0x%"PRIx64") failed: %s", iova,
>> + size, strerror(errno));
>> + }
>> +
>> + return !ret ? 0 : -errno;
>> +}
>> +
>> static const TypeInfo iommufd_backend_info = {
>> .name = TYPE_IOMMUFD_BACKEND,
>> .parent = TYPE_OBJECT,
>> diff --git a/backends/trace-events b/backends/trace-events
>> index feba2baca5f7..11a27cb114b6 100644
>> --- a/backends/trace-events
>> +++ b/backends/trace-events
>> @@ -17,3 +17,4 @@ iommufd_backend_alloc_hwpt(int iommufd, uint32_t dev_id,
>> uint32_t pt_id, uint32_
>> iommufd_backend_alloc_ioas(int iommufd, uint32_t ioas, int ret) "
>> iommufd=%d
>> ioas=%d (%d)"
>> iommufd_backend_free_id(int iommufd, uint32_t id, int ret) " iommufd=%d
>> id=%d (%d)"
>> iommufd_backend_set_dirty(int iommufd, uint32_t hwpt_id, bool start, int
>> ret) " iommufd=%d hwpt=%d enable=%d (%d)"
>> +iommufd_backend_get_dirty_bitmap(int iommufd, uint32_t hwpt_id, uint64_t
>> iova, uint64_t size, uint64_t page_size, int ret) " iommufd=%d hwpt=%d
>> iova=0x%"PRIx64" size=0x%"PRIx64" page_size=0x%"PRIx64" (%d)"
>
> s/hwpt=%d/hwpt=%u
>
/me nods
>> diff --git a/hw/vfio/iommufd.c b/hw/vfio/iommufd.c
>> index 361e659288fd..79b13bd262cc 100644
>> --- a/hw/vfio/iommufd.c
>> +++ b/hw/vfio/iommufd.c
>> @@ -25,6 +25,7 @@
>> #include "qemu/cutils.h"
>> #include "qemu/chardev_open.h"
>> #include "pci.h"
>> +#include "exec/ram_addr.h"
>> #include "migration/migration.h"
>>
>> static int iommufd_cdev_map(const VFIOContainerBase *bcontainer, hwaddr
>> iova,
>> @@ -142,6 +143,34 @@ err:
>> return ret;
>> }
>>
>> +static int iommufd_query_dirty_bitmap(const VFIOContainerBase *bcontainer,
>> + VFIOBitmap *vbmap, uint64_t iova,
>> + uint64_t size)
>> +{
>> + VFIOIOMMUFDContainer *container = container_of(bcontainer,
>> + VFIOIOMMUFDContainer,
>> + bcontainer);
>> + int ret;
>> + VFIOIOASHwpt *hwpt;
>> + unsigned long page_size;
>> +
>> + if (!bcontainer->dirty_pages_supported) {
>
> Do we need this check?
> IIUC, if we got to iommufd_query_dirty_bitmap(), it means
> bcontainer->dirty_pages_supported is already true.
>
Not quite. Look again at vfio_get_dirty_bitmap(); furthermore
vfio_container_query_dirty_bitmap() doesn't check for dirty_pages_supported.
I guess this check should be better placed into container-base class rather than
here.
> Thanks.
>
>> + return 0;
>> + }
>> +
>> + page_size = qemu_real_host_page_size();
>> + QLIST_FOREACH(hwpt, &container->hwpt_list, next) {
>> + ret = iommufd_backend_get_dirty_bitmap(container->be, hwpt->hwpt_id,
>> + iova, size, page_size,
>> + vbmap->bitmap);
>> + if (ret) {
>> + break;
>> + }
>> + }
>> +
>> + return ret;
>> +}
>> +
>> static int iommufd_cdev_getfd(const char *sysfs_path, Error **errp)
>> {
>> long int ret = -ENOTTY;
>> @@ -765,6 +794,7 @@ static void vfio_iommu_iommufd_class_init(ObjectClass
>> *klass, void *data)
>> vioc->pci_hot_reset = iommufd_cdev_pci_hot_reset;
>> vioc->host_iommu_device_init = vfio_cdev_host_iommu_device_init;
>> vioc->set_dirty_page_tracking = iommufd_set_dirty_page_tracking;
>> + vioc->query_dirty_bitmap = iommufd_query_dirty_bitmap;
>> };
>>
>> static const TypeInfo types[] = {
>> diff --git a/include/sysemu/iommufd.h b/include/sysemu/iommufd.h
>> index 562c189dd92c..ba19b7ea4c19 100644
>> --- a/include/sysemu/iommufd.h
>> +++ b/include/sysemu/iommufd.h
>> @@ -55,5 +55,8 @@ int iommufd_backend_alloc_hwpt(int iommufd, uint32_t
>> dev_id,
>> void *data_ptr, uint32_t *out_hwpt);
>> int iommufd_backend_set_dirty_tracking(IOMMUFDBackend *be, uint32_t
>> hwpt_id,
>> bool start);
>> +int iommufd_backend_get_dirty_bitmap(IOMMUFDBackend *be, uint32_t hwpt_id,
>> + uint64_t iova, ram_addr_t size,
>> + uint64_t page_size, uint64_t *data);
>>
>> #endif
>> --
>> 2.39.3
>>
