uio_hv_generic: Query the ringbuffer size for device

[ Upstream commit e566ed5b64177a0c07b677568f623ed31d23406d ]

Query the ring buffer size from pre defined table per device
and use that value for allocating the ring buffer for that
device. Keep the size as current default which is 2 MB if
the device doesn't have any preferred ring size.

Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Reviewed-by: Long Li <longli@microsoft.com>
Link: https://lore.kernel.org/r/1711788723-8593-3-git-send-email-ssengar@linux.microsoft.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 0315fef2aff9 ("uio_hv_generic: Align ring size to system page")
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/uio/uio_hv_generic.c b/drivers/uio/uio_hv_generic.c
index 94dda3d4d509f7f4c12c89fee63c5cea26cc0a81..8cb724095be6d781d4772b199d1cbc980ae555f3 100644 (file)
--- a/drivers/uio/uio_hv_generic.c
+++ b/drivers/uio/uio_hv_generic.c
@@ -249,6 +249,7 @@ hv_uio_probe(struct hv_device *dev,
        struct hv_uio_private_data *pdata;
        void *ring_buffer;
        int ret;
+       size_t ring_size = hv_dev_ring_size(channel);
 
        /* Communicating with host has to be via shared memory not hypercall */
        if (!channel->offermsg.monitor_allocated) {
@@ -256,12 +257,14 @@ hv_uio_probe(struct hv_device *dev,
                return -ENOTSUPP;
        }
 
+       if (!ring_size)
+               ring_size = HV_RING_SIZE * PAGE_SIZE;
+
        pdata = devm_kzalloc(&dev->device, sizeof(*pdata), GFP_KERNEL);
        if (!pdata)
                return -ENOMEM;
 
-       ret = vmbus_alloc_ring(channel, HV_RING_SIZE * PAGE_SIZE,
-                              HV_RING_SIZE * PAGE_SIZE);
+       ret = vmbus_alloc_ring(channel, ring_size, ring_size);
        if (ret)
                return ret;