diff options
| author |   Vitaly Kuznetsov <vkuznets@redhat.com> | 2020-04-06 12:41:51 +0200 |
|---|---|---|
| committer |   Wei Liu <wei.liu@kernel.org> | 2020-04-23 13:17:10 +0000 |
| commit | a276463b7aeb6186e7e4315cccb032773fb31b5d (patch) | |
| tree | 146a66a72e15b62f8f48a6c71fb8f62ca2c50521 /drivers/hv | |
| parent | Drivers: hv: copy from message page only what's needed (diff) | |
| download | linux-dev-a276463b7aeb6186e7e4315cccb032773fb31b5d.tar.xz linux-dev-a276463b7aeb6186e7e4315cccb032773fb31b5d.zip | |
Drivers: hv: allocate the exact needed memory for messages
When we need to pass a buffer with Hyper-V message we don't need to always
allocate 256 bytes for the message: the real message length is known from
the header. Change 'struct onmessage_work_context' to make it possible to
not over-allocate.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20200406104154.45010-3-vkuznets@redhat.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Diffstat (limited to 'drivers/hv')
| -rw-r--r-- | drivers/hv/vmbus_drv.c | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index 183a5b07c3ad..e356ea4752c0 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -1019,7 +1019,10 @@ static struct bus_type hv_bus = { struct onmessage_work_context { struct work_struct work; - struct hv_message msg; + struct { + struct hv_message_header header; + u8 payload[]; + } msg; }; static void vmbus_onmessage_work(struct work_struct *work) @@ -1072,7 +1075,8 @@ void vmbus_on_msg_dpc(unsigned long data) goto msg_handled; if (entry->handler_type == VMHT_BLOCKING) { - ctx = kmalloc(sizeof(*ctx), GFP_ATOMIC); + ctx = kmalloc(sizeof(*ctx) + msg->header.payload_size, + GFP_ATOMIC); if (ctx == NULL) return; @@ -1126,10 +1130,11 @@ static void vmbus_force_channel_rescinded(struct vmbus_channel *channel) WARN_ON(!is_hvsock_channel(channel)); /* - * sizeof(*ctx) is small and the allocation should really not fail, + * Allocation size is small and the allocation should really not fail, * otherwise the state of the hv_sock connections ends up in limbo. */ - ctx = kzalloc(sizeof(*ctx), GFP_KERNEL | __GFP_NOFAIL); + ctx = kzalloc(sizeof(*ctx) + sizeof(*rescind), + GFP_KERNEL | __GFP_NOFAIL); /* * So far, these are not really used by Linux. Just set them to the @@ -1139,7 +1144,7 @@ static void vmbus_force_channel_rescinded(struct vmbus_channel *channel) ctx->msg.header.payload_size = sizeof(*rescind); /* These values are actually used by Linux. */ - rescind = (struct vmbus_channel_rescind_offer *)ctx->msg.u.payload; + rescind = (struct vmbus_channel_rescind_offer *)ctx->msg.payload; rescind->header.msgtype = CHANNELMSG_RESCIND_CHANNELOFFER; rescind->child_relid = channel->offermsg.child_relid; |