Re: [Resend RFC PATCH V2 11/12] HV/Netvsc: Add Isolation VM support for netvsc driver

From: Tianyu Lan
Date: Thu Apr 15 2021 - 04:40:00 EST




On 4/14/2021 11:50 PM, Christoph Hellwig wrote:
+struct dma_range {
+ dma_addr_t dma;
+ u32 mapping_size;
+};

That's a rather generic name that is bound to create a conflict sooner
or later.

Good point. Will update.


#include "hyperv_net.h"
#include "netvsc_trace.h"
+#include "../../hv/hyperv_vmbus.h"

Please move public interfaces out of the private header rather than doing
this.

OK. Will update.


+ if (hv_isolation_type_snp()) {
+ area = get_vm_area(buf_size, VM_IOREMAP);

Err, no. get_vm_area is private a for a reason.

+ if (!area)
+ goto cleanup;
+
+ vaddr = (unsigned long)area->addr;
+ for (i = 0; i < buf_size / HV_HYP_PAGE_SIZE; i++) {
+ extra_phys = (virt_to_hvpfn(net_device->recv_buf + i * HV_HYP_PAGE_SIZE)
+ << HV_HYP_PAGE_SHIFT) + ms_hyperv.shared_gpa_boundary;
+ ret |= ioremap_page_range(vaddr + i * HV_HYP_PAGE_SIZE,
+ vaddr + (i + 1) * HV_HYP_PAGE_SIZE,
+ extra_phys, PAGE_KERNEL_IO);
+ }
+
+ if (ret)
+ goto cleanup;

And this is not something a driver should ever do. I think you are badly
reimplementing functionality that should be in the dma coherent allocator
here.

OK. I will try hiding these in the Hyper-V dma ops callback. Thanks.