hv_netvsc: Remove second mapping of send and recv buffers

With changes to how Hyper-V guest VMs flip memory between private
(encrypted) and shared (decrypted), creating a second kernel virtual
mapping for shared memory is no longer necessary.  Everything needed
for the transition to shared is handled by set_memory_decrypted().

As such, remove the code to create and manage the second
mapping for the pre-allocated send and recv buffers.  This mapping
is the last user of hv_map_memory()/hv_unmap_memory(), so delete
these functions as well.  Finally, hv_map_memory() is the last
user of vmap_pfn() in Hyper-V guest code, so remove the Kconfig
selection of VMAP_PFN.

Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Reviewed-by: Tianyu Lan <Tianyu.Lan@microsoft.com>
Link: https://lore.kernel.org/r/1679838727-87310-11-git-send-email-mikelley@microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>

1 files changed, 0 insertions, 28 deletions

diff --git a/arch/x86/hyperv/ivm.c b/arch/x86/hyperv/ivm.c
index f6a020cb1a24..127d5b7b63de 100644
--- a/arch/x86/hyperv/ivm.c
+++ b/arch/x86/hyperv/ivm.c
@@ -376,34 +376,6 @@ void __init hv_vtom_init(void)
 
 #endif /* CONFIG_AMD_MEM_ENCRYPT */
 
-/*
- * hv_map_memory - map memory to extra space in the AMD SEV-SNP Isolation VM.
- */
-void *hv_map_memory(void *addr, unsigned long size)
-{
-	unsigned long *pfns = kcalloc(size / PAGE_SIZE,
-				      sizeof(unsigned long), GFP_KERNEL);
-	void *vaddr;
-	int i;
-
-	if (!pfns)
-		return NULL;
-
-	for (i = 0; i < size / PAGE_SIZE; i++)
-		pfns[i] = vmalloc_to_pfn(addr + i * PAGE_SIZE) +
-			(ms_hyperv.shared_gpa_boundary >> PAGE_SHIFT);
-
-	vaddr = vmap_pfn(pfns, size / PAGE_SIZE, pgprot_decrypted(PAGE_KERNEL));
-	kfree(pfns);
-
-	return vaddr;
-}
-
-void hv_unmap_memory(void *addr)
-{
-	vunmap(addr);
-}
-
 enum hv_isolation_type hv_get_isolation_type(void)
 {
 	if (!(ms_hyperv.priv_high & HV_ISOLATION))