[PATCH AUTOSEL 4.19 32/45] Input: hyperv-keyboard: Use in-place iterator API in the channel callback

Sasha Levin
2019-08-29T18:23:49Z

From: Dexuan Cui <decui@microsoft.com>

[ Upstream commit d09bc83640d524b8467a660db7b1d15e6562a1de ]

Simplify the ring buffer handling with the in-place API.

Also avoid the dynamic allocation and the memory leak in the channel
callback function.

Signed-off-by: Dexuan Cui <decui@microsoft.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/input/serio/hyperv-keyboard.c | 35 +++++----------------------
1 file changed, 6 insertions(+), 29 deletions(-)

diff --git a/drivers/input/serio/hyperv-keyboard.c b/drivers/input/serio/hyperv-keyboard.c
index a8b9be3e28db7..7d0a5ccf57751 100644
--- a/drivers/input/serio/hyperv-keyboard.c
+++ b/drivers/input/serio/hyperv-keyboard.c
@@ -245,40 +245,17 @@ static void hv_kbd_handle_received_packet(struct hv_device *hv_dev,

static void hv_kbd_on_channel_callback(void *context)
{
+ struct vmpacket_descriptor *desc;
struct hv_device *hv_dev = context;
- void *buffer;
- int bufferlen = 0x100; /* Start with sensible size */
u32 bytes_recvd;
u64 req_id;
- int error;

- buffer = kmalloc(bufferlen, GFP_ATOMIC);
- if (!buffer)
- return;
-
- while (1) {
- error = vmbus_recvpacket_raw(hv_dev->channel, buffer, bufferlen,
- &bytes_recvd, &req_id);
- switch (error) {
- case 0:
- if (bytes_recvd == 0) {
- kfree(buffer);
- return;
- }
-
- hv_kbd_handle_received_packet(hv_dev, buffer,
- bytes_recvd, req_id);
- break;
+ foreach_vmbus_pkt(desc, hv_dev->channel) {
+ bytes_recvd = desc->len8 * 8;
+ req_id = desc->trans_id;

- case -ENOBUFS:
- kfree(buffer);
- /* Handle large packet */
- bufferlen = bytes_recvd;
- buffer = kmalloc(bytes_recvd, GFP_ATOMIC);
- if (!buffer)
- return;
- break;
- }
+ hv_kbd_handle_received_packet(hv_dev, desc, bytes_recvd,
+ req_id);
}
}

--
2.20.1