>> > >> > IMO, this seems like adding too much code to reduce the call length for a >> > very specific case. If there aren't any strong opinion on this, I'm planning to >> > leave this code as it is. >> >> a slight difference. if mem_count==0 the result should always succeed >> no matter nvgrace_gpu_map_device_mem() succeeds or not. Of course >> if it fails it's already a big problem probably nobody cares about the subtle >> difference when reading non-exist range. >> >> but regarding to readability it's still clearer: >> >> if (mem_count) >> nvgrace_gpu_map_and_read(); >> > > The below has better flow imo vs conditionalizing the call to > map_and_read/write and subsequent error handling, but I don't think > either adds too much code. Thanks, > > Alex > > --- a/drivers/vfio/pci/nvgrace-gpu/main.c > +++ b/drivers/vfio/pci/nvgrace-gpu/main.c > @@ -429,6 +429,9 @@ nvgrace_gpu_map_and_read(struct nvgrace_gpu_vfio_pci_core_device *nvdev, > u64 offset = *ppos & VFIO_PCI_OFFSET_MASK; > int ret; > > + if (!mem_count) > + return 0; > + > /* > * Handle read on the BAR regions. Map to the target device memory > * physical address and copy to the request read buffer. > @@ -547,6 +550,9 @@ nvgrace_gpu_map_and_write(struct nvgrace_gpu_vfio_pci_core_device *nvdev, > loff_t pos = *ppos & VFIO_PCI_OFFSET_MASK; > int ret; > > + if (!mem_count) > + return 0; > + > ret = nvgrace_gpu_map_device_mem(index, nvdev); > if (ret) > return ret; Sure, will update it as mentioned above.
