[PATCH 1/1] Drivers: hv: vmbus: Remove unused code to check for subchannels

From: Michael Kelley
Date: Mon Oct 25 2021 - 15:59:39 EST


The last caller of vmbus_are_subchannels_present() was removed in commit
c967590457ca ("scsi: storvsc: Fix a race in sub-channel creation that can cause panic").

Remove this dead code, and the utility function invoke_sc_cb() that it is
the only caller of.

Signed-off-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>
---
drivers/hv/channel_mgmt.c | 34 ----------------------------------
include/linux/hyperv.h | 13 -------------
2 files changed, 47 deletions(-)

diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
index 1423085..2829575 100644
--- a/drivers/hv/channel_mgmt.c
+++ b/drivers/hv/channel_mgmt.c
@@ -1581,21 +1581,6 @@ int vmbus_request_offers(void)
return ret;
}

-static void invoke_sc_cb(struct vmbus_channel *primary_channel)
-{
- struct list_head *cur, *tmp;
- struct vmbus_channel *cur_channel;
-
- if (primary_channel->sc_creation_callback == NULL)
- return;
-
- list_for_each_safe(cur, tmp, &primary_channel->sc_list) {
- cur_channel = list_entry(cur, struct vmbus_channel, sc_list);
-
- primary_channel->sc_creation_callback(cur_channel);
- }
-}
-
void vmbus_set_sc_create_callback(struct vmbus_channel *primary_channel,
void (*sc_cr_cb)(struct vmbus_channel *new_sc))
{
@@ -1603,25 +1588,6 @@ void vmbus_set_sc_create_callback(struct vmbus_channel *primary_channel,
}
EXPORT_SYMBOL_GPL(vmbus_set_sc_create_callback);

-bool vmbus_are_subchannels_present(struct vmbus_channel *primary)
-{
- bool ret;
-
- ret = !list_empty(&primary->sc_list);
-
- if (ret) {
- /*
- * Invoke the callback on sub-channel creation.
- * This will present a uniform interface to the
- * clients.
- */
- invoke_sc_cb(primary);
- }
-
- return ret;
-}
-EXPORT_SYMBOL_GPL(vmbus_are_subchannels_present);
-
void vmbus_set_chn_rescind_callback(struct vmbus_channel *channel,
void (*chn_rescind_cb)(struct vmbus_channel *))
{
diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index ddc8713..836fae2 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -1100,19 +1100,6 @@ void vmbus_set_sc_create_callback(struct vmbus_channel *primary_channel,
void vmbus_set_chn_rescind_callback(struct vmbus_channel *channel,
void (*chn_rescind_cb)(struct vmbus_channel *));

-/*
- * Check if sub-channels have already been offerred. This API will be useful
- * when the driver is unloaded after establishing sub-channels. In this case,
- * when the driver is re-loaded, the driver would have to check if the
- * subchannels have already been established before attempting to request
- * the creation of sub-channels.
- * This function returns TRUE to indicate that subchannels have already been
- * created.
- * This function should be invoked after setting the callback function for
- * sub-channel creation.
- */
-bool vmbus_are_subchannels_present(struct vmbus_channel *primary);
-
/* The format must be the same as struct vmdata_gpa_direct */
struct vmbus_channel_packet_page_buffer {
u16 type;
--
1.8.3.1