[PATCH V5 04/12] Drivers: hv: vmbus: Mark vmbus ring buffer visible to host in Isolation VM

Tianyu Lan
2021-09-14T13:39:47Z

From: Tianyu Lan <Tianyu.Lan@microsoft.com>

Mark vmbus ring buffer visible with set_memory_decrypted() when
establish gpadl handle.

Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com>
---
Change sincv v4
* Change gpadl handle in netvsc and uio driver from u32 to
struct vmbus_gpadl.
* Change vmbus_establish_gpadl()'s gpadl_handle parameter
to vmbus_gpadl data structure.

Change since v3:
* Change vmbus_teardown_gpadl() parameter and put gpadl handle,
buffer and buffer size in the struct vmbus_gpadl.
---
drivers/hv/channel.c | 54 ++++++++++++++++++++++++---------
drivers/net/hyperv/hyperv_net.h | 5 +--
drivers/net/hyperv/netvsc.c | 17 ++++++-----
drivers/uio/uio_hv_generic.c | 20 ++++++------
include/linux/hyperv.h | 12 ++++++--
5 files changed, 71 insertions(+), 37 deletions(-)

diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
index f3761c73b074..cf419eb1de77 100644
--- a/drivers/hv/channel.c
+++ b/drivers/hv/channel.c
@@ -17,6 +17,7 @@
#include <linux/hyperv.h>
#include <linux/uio.h>
#include <linux/interrupt.h>
+#include <linux/set_memory.h>
#include <asm/page.h>
#include <asm/mshyperv.h>

@@ -456,7 +457,7 @@ static int create_gpadl_header(enum hv_gpadl_type type, void *kbuffer,
static int __vmbus_establish_gpadl(struct vmbus_channel *channel,
enum hv_gpadl_type type, void *kbuffer,
u32 size, u32 send_offset,
- u32 *gpadl_handle)
+ struct vmbus_gpadl *gpadl)
{
struct vmbus_channel_gpadl_header *gpadlmsg;
struct vmbus_channel_gpadl_body *gpadl_body;
@@ -474,6 +475,15 @@ static int __vmbus_establish_gpadl(struct vmbus_channel *channel,
if (ret)
return ret;

+ ret = set_memory_decrypted((unsigned long)kbuffer,
+ HVPFN_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);
msginfo->waiting_channel = channel;

@@ -537,7 +547,10 @@ static int __vmbus_establish_gpadl(struct vmbus_channel *channel,
}

/* At this point, we received the gpadl created msg */
- *gpadl_handle = gpadlmsg->gpadl;
+ gpadl->gpadl_handle = gpadlmsg->gpadl;
+ gpadl->buffer = kbuffer;
+ gpadl->size = size;
+

cleanup:
spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
@@ -549,6 +562,11 @@ static int __vmbus_establish_gpadl(struct vmbus_channel *channel,
}

kfree(msginfo);
+
+ if (ret)
+ set_memory_encrypted((unsigned long)kbuffer,
+ HVPFN_UP(size));
+
return ret;
}

@@ -561,10 +579,10 @@ static int __vmbus_establish_gpadl(struct vmbus_channel *channel,
* @gpadl_handle: some funky thing
*/
int vmbus_establish_gpadl(struct vmbus_channel *channel, void *kbuffer,
- u32 size, u32 *gpadl_handle)
+ u32 size, struct vmbus_gpadl *gpadl)
{
return __vmbus_establish_gpadl(channel, HV_GPADL_BUFFER, kbuffer, size,
- 0U, gpadl_handle);
+ 0U, gpadl);
}
EXPORT_SYMBOL_GPL(vmbus_establish_gpadl);

@@ -639,6 +657,7 @@ static int __vmbus_open(struct vmbus_channel *newchannel,
struct vmbus_channel_open_channel *open_msg;
struct vmbus_channel_msginfo *open_info = NULL;
struct page *page = newchannel->ringbuffer_page;
+ struct vmbus_gpadl gpadl;
u32 send_pages, recv_pages;
unsigned long flags;
int err;
@@ -675,7 +694,7 @@ static int __vmbus_open(struct vmbus_channel *newchannel,
goto error_clean_ring;

/* Establish the gpadl for the ring buffer */
- newchannel->ringbuffer_gpadlhandle = 0;
+ newchannel->ringbuffer_gpadlhandle.gpadl_handle = 0;

err = __vmbus_establish_gpadl(newchannel, HV_GPADL_RING,
page_address(newchannel->ringbuffer_page),
@@ -701,7 +720,8 @@ static int __vmbus_open(struct vmbus_channel *newchannel,
open_msg->header.msgtype = CHANNELMSG_OPENCHANNEL;
open_msg->openid = newchannel->offermsg.child_relid;
open_msg->child_relid = newchannel->offermsg.child_relid;
- open_msg->ringbuffer_gpadlhandle = newchannel->ringbuffer_gpadlhandle;
+ open_msg->ringbuffer_gpadlhandle
+ = newchannel->ringbuffer_gpadlhandle.gpadl_handle;
/*
* The unit of ->downstream_ringbuffer_pageoffset is HV_HYP_PAGE and
* the unit of ->ringbuffer_send_offset (i.e. send_pages) is PAGE, so
@@ -759,8 +779,8 @@ static int __vmbus_open(struct vmbus_channel *newchannel,
error_free_info:
kfree(open_info);
error_free_gpadl:
- vmbus_teardown_gpadl(newchannel, newchannel->ringbuffer_gpadlhandle);
- newchannel->ringbuffer_gpadlhandle = 0;
+ vmbus_teardown_gpadl(newchannel, &newchannel->ringbuffer_gpadlhandle);
+ newchannel->ringbuffer_gpadlhandle.gpadl_handle = 0;
error_clean_ring:
hv_ringbuffer_cleanup(&newchannel->outbound);
hv_ringbuffer_cleanup(&newchannel->inbound);
@@ -806,7 +826,7 @@ EXPORT_SYMBOL_GPL(vmbus_open);
/*
* vmbus_teardown_gpadl -Teardown the specified GPADL handle
*/
-int vmbus_teardown_gpadl(struct vmbus_channel *channel, u32 gpadl_handle)
+int vmbus_teardown_gpadl(struct vmbus_channel *channel, struct vmbus_gpadl *gpadl)
{
struct vmbus_channel_gpadl_teardown *msg;
struct vmbus_channel_msginfo *info;
@@ -825,7 +845,7 @@ int vmbus_teardown_gpadl(struct vmbus_channel *channel, u32 gpadl_handle)

msg->header.msgtype = CHANNELMSG_GPADL_TEARDOWN;
msg->child_relid = channel->offermsg.child_relid;
- msg->gpadl = gpadl_handle;
+ msg->gpadl = gpadl->gpadl_handle;

spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
list_add_tail(&info->msglistentry,
@@ -859,6 +879,12 @@ int vmbus_teardown_gpadl(struct vmbus_channel *channel, u32 gpadl_handle)
spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);

kfree(info);
+
+ ret = set_memory_encrypted((unsigned long)gpadl->buffer,
+ HVPFN_UP(gpadl->size));
+ if (ret)
+ pr_warn("Fail to set mem host visibility in GPADL teardown %d.\n", ret);
+
return ret;
}
EXPORT_SYMBOL_GPL(vmbus_teardown_gpadl);
@@ -896,6 +922,7 @@ void vmbus_reset_channel_cb(struct vmbus_channel *channel)
static int vmbus_close_internal(struct vmbus_channel *channel)
{
struct vmbus_channel_close_channel *msg;
+ struct vmbus_gpadl gpadl;
int ret;

vmbus_reset_channel_cb(channel);
@@ -933,9 +960,8 @@ static int vmbus_close_internal(struct vmbus_channel *channel)
}

/* Tear down the gpadl for the channel's ring buffer */
- else if (channel->ringbuffer_gpadlhandle) {
- ret = vmbus_teardown_gpadl(channel,
- channel->ringbuffer_gpadlhandle);
+ else if (channel->ringbuffer_gpadlhandle.gpadl_handle) {
+ ret = vmbus_teardown_gpadl(channel, &channel->ringbuffer_gpadlhandle);
if (ret) {
pr_err("Close failed: teardown gpadl return %d\n", ret);
/*
@@ -944,7 +970,7 @@ static int vmbus_close_internal(struct vmbus_channel *channel)
*/
}

- channel->ringbuffer_gpadlhandle = 0;
+ channel->ringbuffer_gpadlhandle.gpadl_handle = 0;
}

if (!ret)
diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
index bc48855dff10..315278a7cf88 100644
--- a/drivers/net/hyperv/hyperv_net.h
+++ b/drivers/net/hyperv/hyperv_net.h
@@ -1075,14 +1075,15 @@ struct netvsc_device {
/* Receive buffer allocated by us but manages by NetVSP */
void *recv_buf;
u32 recv_buf_size; /* allocated bytes */
- u32 recv_buf_gpadl_handle;
+ struct vmbus_gpadl recv_buf_gpadl_handle;
u32 recv_section_cnt;
u32 recv_section_size;
u32 recv_completion_cnt;

/* Send buffer allocated by us */
void *send_buf;
- u32 send_buf_gpadl_handle;
+ u32 send_buf_size;
+ struct vmbus_gpadl send_buf_gpadl_handle;
u32 send_section_cnt;
u32 send_section_size;
unsigned long *send_section_map;
diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index 7bd935412853..1f87e570ed2b 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -278,9 +278,9 @@ static void netvsc_teardown_recv_gpadl(struct hv_device *device,
{
int ret;

- if (net_device->recv_buf_gpadl_handle) {
+ if (net_device->recv_buf_gpadl_handle.gpadl_handle) {
ret = vmbus_teardown_gpadl(device->channel,
- net_device->recv_buf_gpadl_handle);
+ &net_device->recv_buf_gpadl_handle);

/* If we failed here, we might as well return and have a leak
* rather than continue and a bugchk
@@ -290,7 +290,7 @@ static void netvsc_teardown_recv_gpadl(struct hv_device *device,
"unable to teardown receive buffer's gpadl\n");
return;
}
- net_device->recv_buf_gpadl_handle = 0;
+ net_device->recv_buf_gpadl_handle.gpadl_handle = 0;
}
}

@@ -300,9 +300,9 @@ static void netvsc_teardown_send_gpadl(struct hv_device *device,
{
int ret;

- if (net_device->send_buf_gpadl_handle) {
+ if (net_device->send_buf_gpadl_handle.gpadl_handle) {
ret = vmbus_teardown_gpadl(device->channel,
- net_device->send_buf_gpadl_handle);
+ &net_device->send_buf_gpadl_handle);

/* If we failed here, we might as well return and have a leak
* rather than continue and a bugchk
@@ -312,7 +312,7 @@ static void netvsc_teardown_send_gpadl(struct hv_device *device,
"unable to teardown send buffer's gpadl\n");
return;
}
- net_device->send_buf_gpadl_handle = 0;
+ net_device->send_buf_gpadl_handle.gpadl_handle = 0;
}
}

@@ -380,7 +380,7 @@ static int netvsc_init_buf(struct hv_device *device,
memset(init_packet, 0, sizeof(struct nvsp_message));
init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_RECV_BUF;
init_packet->msg.v1_msg.send_recv_buf.
- gpadl_handle = net_device->recv_buf_gpadl_handle;
+ gpadl_handle = net_device->recv_buf_gpadl_handle.gpadl_handle;
init_packet->msg.v1_msg.
send_recv_buf.id = NETVSC_RECEIVE_BUFFER_ID;

@@ -463,6 +463,7 @@ static int netvsc_init_buf(struct hv_device *device,
ret = -ENOMEM;
goto cleanup;
}
+ net_device->send_buf_size = buf_size;

/* Establish the gpadl handle for this buffer on this
* channel. Note: This call uses the vmbus connection rather
@@ -482,7 +483,7 @@ static int netvsc_init_buf(struct hv_device *device,
memset(init_packet, 0, sizeof(struct nvsp_message));
init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_SEND_BUF;
init_packet->msg.v1_msg.send_send_buf.gpadl_handle =
- net_device->send_buf_gpadl_handle;
+ net_device->send_buf_gpadl_handle.gpadl_handle;
init_packet->msg.v1_msg.send_send_buf.id = NETVSC_SEND_BUFFER_ID;

trace_nvsp_send(ndev, init_packet);
diff --git a/drivers/uio/uio_hv_generic.c b/drivers/uio/uio_hv_generic.c
index 652fe2547587..548243dcd895 100644
--- a/drivers/uio/uio_hv_generic.c
+++ b/drivers/uio/uio_hv_generic.c
@@ -58,11 +58,11 @@ struct hv_uio_private_data {
atomic_t refcnt;

void *recv_buf;
- u32 recv_gpadl;
+ struct vmbus_gpadl recv_gpadl;
char recv_name[32]; /* "recv_4294967295" */

void *send_buf;
- u32 send_gpadl;
+ struct vmbus_gpadl send_gpadl;
char send_name[32];
};

@@ -179,15 +179,15 @@ hv_uio_new_channel(struct vmbus_channel *new_sc)
static void
hv_uio_cleanup(struct hv_device *dev, struct hv_uio_private_data *pdata)
{
- if (pdata->send_gpadl) {
- vmbus_teardown_gpadl(dev->channel, pdata->send_gpadl);
- pdata->send_gpadl = 0;
+ if (pdata->send_gpadl.gpadl_handle) {
+ vmbus_teardown_gpadl(dev->channel, &pdata->send_gpadl);
+ pdata->send_gpadl.gpadl_handle = 0;
vfree(pdata->send_buf);
}

- if (pdata->recv_gpadl) {
- vmbus_teardown_gpadl(dev->channel, pdata->recv_gpadl);
- pdata->recv_gpadl = 0;
+ if (pdata->recv_gpadl.gpadl_handle) {
+ vmbus_teardown_gpadl(dev->channel, &pdata->recv_gpadl);
+ pdata->recv_gpadl.gpadl_handle = 0;
vfree(pdata->recv_buf);
}
}
@@ -303,7 +303,7 @@ hv_uio_probe(struct hv_device *dev,

/* put Global Physical Address Label in name */
snprintf(pdata->recv_name, sizeof(pdata->recv_name),
- "recv:%u", pdata->recv_gpadl);
+ "recv:%u", pdata->recv_gpadl.gpadl_handle);
pdata->info.mem[RECV_BUF_MAP].name = pdata->recv_name;
pdata->info.mem[RECV_BUF_MAP].addr
= (uintptr_t)pdata->recv_buf;
@@ -324,7 +324,7 @@ hv_uio_probe(struct hv_device *dev,
}

snprintf(pdata->send_name, sizeof(pdata->send_name),
- "send:%u", pdata->send_gpadl);
+ "send:%u", pdata->send_gpadl.gpadl_handle);
pdata->info.mem[SEND_BUF_MAP].name = pdata->send_name;
pdata->info.mem[SEND_BUF_MAP].addr
= (uintptr_t)pdata->send_buf;
diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index ddc8713ce57b..a9e0bc3b1511 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -803,6 +803,12 @@ struct vmbus_device {

#define VMBUS_DEFAULT_MAX_PKT_SIZE 4096

+struct vmbus_gpadl {
+ u32 gpadl_handle;
+ u32 size;
+ void *buffer;
+};
+
struct vmbus_channel {
struct list_head listentry;

@@ -822,7 +828,7 @@ struct vmbus_channel {
bool rescind_ref; /* got rescind msg, got channel reference */
struct completion rescind_event;

- u32 ringbuffer_gpadlhandle;
+ struct vmbus_gpadl ringbuffer_gpadlhandle;

/* Allocated memory for ring buffer */
struct page *ringbuffer_page;
@@ -1192,10 +1198,10 @@ extern int vmbus_sendpacket_mpb_desc(struct vmbus_channel *channel,
extern int vmbus_establish_gpadl(struct vmbus_channel *channel,
void *kbuffer,
u32 size,
- u32 *gpadl_handle);
+ struct vmbus_gpadl *gpadl);

extern int vmbus_teardown_gpadl(struct vmbus_channel *channel,
- u32 gpadl_handle);
+ struct vmbus_gpadl *gpadl);

void vmbus_reset_channel_cb(struct vmbus_channel *channel);

--
2.25.1