Confidential VMBus is built around using buffers not shared with
the host.
Support allocating encrypted buffers when requested.
Signed-off-by: Roman Kisel <rom...@linux.microsoft.com>
---
drivers/hv/channel.c | 49 +++++++++++++++++++++++----------------
drivers/hv/hyperv_vmbus.h | 3 ++-
drivers/hv/ring_buffer.c | 5 ++--
3 files changed, 34 insertions(+), 23 deletions(-)
diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
index 35f26fa1ffe7..051eeba800f2 100644
--- a/drivers/hv/channel.c
+++ b/drivers/hv/channel.c
@@ -443,20 +443,23 @@ static int __vmbus_establish_gpadl(struct vmbus_channel
*channel,
return ret;
}
- /*
- * Set the "decrypted" flag to true for the set_memory_decrypted()
- * success case. In the failure case, the encryption state of the
- * memory is unknown. Leave "decrypted" as true to ensure the
- * memory will be leaked instead of going back on the free list.
- */
- gpadl->decrypted = true;
- ret = set_memory_decrypted((unsigned long)kbuffer,
- PFN_UP(size));
- if (ret) {
- dev_warn(&channel->device_obj->device,
- "Failed to set host visibility for new GPADL %d.\n",
- ret);
- return ret;
+ gpadl->decrypted = !((channel->co_external_memory && type ==
HV_GPADL_BUFFER) ||
+ (channel->co_ring_buffer && type == HV_GPADL_RING));
+ if (gpadl->decrypted) {
+ /*
+ * The "decrypted" flag being true assumes that
set_memory_decrypted() succeeds.
+ * But if it fails, the encryption state of the memory is
unknown. In that case,
+ * leave "decrypted" as true to ensure the memory is leaked
instead of going back
+ * on the free list.
+ */
+ ret = set_memory_decrypted((unsigned long)kbuffer,
+ PFN_UP(size));
+ if (ret) {
+ dev_warn(&channel->device_obj->device,
+ "Failed to set host visibility for new GPADL
%d.\n",
+ ret);
+ return ret;
+ }
}
init_completion(&msginfo->waitevent);
@@ -544,8 +547,10 @@ static int __vmbus_establish_gpadl(struct vmbus_channel
*channel,
* left as true so the memory is leaked instead of being
* put back on the free list.
*/
- if (!set_memory_encrypted((unsigned long)kbuffer, PFN_UP(size)))
- gpadl->decrypted = false;
+ if (gpadl->decrypted) {
+ if (!set_memory_encrypted((unsigned long)kbuffer,
PFN_UP(size)))
+ gpadl->decrypted = false;
+ }
}
return ret;
@@ -676,12 +681,13 @@ static int __vmbus_open(struct vmbus_channel *newchannel,
goto error_clean_ring;
err = hv_ringbuffer_init(&newchannel->outbound,
- page, send_pages, 0);
+ page, send_pages, 0,
newchannel->co_ring_buffer);
if (err)
goto error_free_gpadl;
err = hv_ringbuffer_init(&newchannel->inbound, &page[send_pages],
- recv_pages, newchannel->max_pkt_size);
+ recv_pages, newchannel->max_pkt_size,
+ newchannel->co_ring_buffer);
if (err)
goto error_free_gpadl;
@@ -862,8 +868,11 @@ int vmbus_teardown_gpadl(struct vmbus_channel *channel,
struct vmbus_gpadl *gpad
kfree(info);
- ret = set_memory_encrypted((unsigned long)gpadl->buffer,
- PFN_UP(gpadl->size));
+ if (gpadl->decrypted)
+ ret = set_memory_encrypted((unsigned long)gpadl->buffer,
+ PFN_UP(gpadl->size));
+ else
+ ret = 0;
if (ret)
pr_warn("Fail to set mem host visibility in GPADL teardown
%d.\n", ret);
diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h
index 2873703d08a9..beae68a70939 100644
--- a/drivers/hv/hyperv_vmbus.h
+++ b/drivers/hv/hyperv_vmbus.h
@@ -200,7 +200,8 @@ extern int hv_synic_cleanup(unsigned int cpu);
void hv_ringbuffer_pre_init(struct vmbus_channel *channel);
int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info,
- struct page *pages, u32 pagecnt, u32 max_pkt_size);
+ struct page *pages, u32 pagecnt, u32 max_pkt_size,
+ bool confidential);
void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info);
diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c
index 3c9b02471760..05c2cd42fc75 100644
--- a/drivers/hv/ring_buffer.c
+++ b/drivers/hv/ring_buffer.c
@@ -183,7 +183,8 @@ void hv_ringbuffer_pre_init(struct vmbus_channel *channel)
/* Initialize the ring buffer. */
int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info,
- struct page *pages, u32 page_cnt, u32 max_pkt_size)
+ struct page *pages, u32 page_cnt, u32 max_pkt_size,
+ bool confidential)
{
struct page **pages_wraparound;
int i;
@@ -207,7 +208,7 @@ int hv_ringbuffer_init(struct hv_ring_buffer_info
*ring_info,
ring_info->ring_buffer = (struct hv_ring_buffer *)
vmap(pages_wraparound, page_cnt * 2 - 1, VM_MAP,
- pgprot_decrypted(PAGE_KERNEL));
+ confidential ? PAGE_KERNEL :
pgprot_decrypted(PAGE_KERNEL));
kfree(pages_wraparound);
if (!ring_info->ring_buffer)
--
2.43.0
