lkml.org 
[lkml]   [2019]   [Dec]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH V2,net-next, 1/3] Drivers: hv: vmbus: Add a dev_num variable based on channel offer sequence
Date
This number is set to the first available number, starting from zero,
when a vmbus device’s primary channel is offered.
It will be used for stable naming when Async probing is used.

Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
---
Changes
V2:
Use nest loops in hv_set_devnum, instead of goto.

drivers/hv/channel_mgmt.c | 38 ++++++++++++++++++++++++++++++++++++--
include/linux/hyperv.h | 6 ++++++
2 files changed, 42 insertions(+), 2 deletions(-)

diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
index 8eb1675..00fa2db 100644
--- a/drivers/hv/channel_mgmt.c
+++ b/drivers/hv/channel_mgmt.c
@@ -315,6 +315,8 @@ static struct vmbus_channel *alloc_channel(void)
if (!channel)
return NULL;

+ channel->dev_num = HV_DEV_NUM_INVALID;
+
spin_lock_init(&channel->lock);
init_completion(&channel->rescind_event);

@@ -541,6 +543,36 @@ static void vmbus_add_channel_work(struct work_struct *work)
}

/*
+ * Get the first available device number of its type, then
+ * record it in the channel structure.
+ */
+static void hv_set_devnum(struct vmbus_channel *newchannel)
+{
+ struct vmbus_channel *channel;
+ int i = -1;
+ bool found;
+
+ BUG_ON(!mutex_is_locked(&vmbus_connection.channel_mutex));
+
+ do {
+ i++;
+ found = false;
+
+ list_for_each_entry(channel, &vmbus_connection.chn_list,
+ listentry) {
+ if (i == channel->dev_num &&
+ guid_equal(&channel->offermsg.offer.if_type,
+ &newchannel->offermsg.offer.if_type)) {
+ found = true;
+ break;
+ }
+ }
+ } while (found);
+
+ newchannel->dev_num = i;
+}
+
+/*
* vmbus_process_offer - Process the offer by creating a channel/device
* associated with this offer
*/
@@ -573,10 +605,12 @@ static void vmbus_process_offer(struct vmbus_channel *newchannel)
}
}

- if (fnew)
+ if (fnew) {
+ hv_set_devnum(newchannel);
+
list_add_tail(&newchannel->listentry,
&vmbus_connection.chn_list);
- else {
+ } else {
/*
* Check to see if this is a valid sub-channel.
*/
diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index 26f3aee..4f110c5 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -718,6 +718,8 @@ struct vmbus_device {
bool perf_device;
};

+#define HV_DEV_NUM_INVALID (-1)
+
struct vmbus_channel {
struct list_head listentry;

@@ -849,6 +851,10 @@ struct vmbus_channel {
*/
struct vmbus_channel *primary_channel;
/*
+ * Used for device naming based on channel offer sequence.
+ */
+ int dev_num;
+ /*
* Support per-channel state for use by vmbus drivers.
*/
void *per_channel_state;
--
1.8.3.1
\
 
 \ /
  Last update: 2019-12-30 21:15    [W:0.096 / U:0.592 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site