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authorKimberly Brown <kimbrownkd@gmail.com>2019-03-14 16:05:00 -0400
committerSasha Levin <sashal@kernel.org>2019-04-10 18:58:56 -0400
commitfcedbb293ee4d67399a6c231c5e8b7ceecfac9bf (patch)
treec2eaa2f29e8042fa607f3d2374f44c601fdab7d4 /drivers/hv
parent46fc15487d02451448c11b83c4d086d87a6ad588 (diff)
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Drivers: hv: vmbus: Refactor chan->state if statement
The chan->state "if statement" was introduced in commit 6712cc9c2211 ("vmbus: don't return values for uninitalized channels"). That commit states that the purpose of the chan->state "if statement" is to prevent returning garbage or causing a kernel OOPS when the channel ring buffer is not initialized. The changes in this patch provide the same protection. Refactor the chan->state “if statement” in vmbus_chan_attr_show(): - Instead of checking the channel state in the "if statement", check whether the channel ring buffer pointer is NULL. Checking the ring buffer pointer makes this code consistent with hv_ringbuffer_get_debuginfo(). - Move the "if statement" to the four "_show" functions that access a channel ring buffer. Only four of the channel-level "_show" functions access a ring buffer. The ring buffer pointer does not need to be checked before calling the other "_show" functions, and moving the ring buffer pointer "if statement" to the "_show" functions that access a ring buffer makes the purpose of the "if statement" clear. Signed-off-by: Kimberly Brown <kimbrownkd@gmail.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/hv')
-rw-r--r--drivers/hv/vmbus_drv.c15
1 files changed, 12 insertions, 3 deletions
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index b23aea86d029..6aa79b6a6750 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -1435,9 +1435,6 @@ static ssize_t vmbus_chan_attr_show(struct kobject *kobj,
if (!attribute->show)
return -EIO;
- if (chan->state != CHANNEL_OPENED_STATE)
- return -EINVAL;
-
return attribute->show(chan, buf);
}
@@ -1449,6 +1446,9 @@ static ssize_t out_mask_show(const struct vmbus_channel *channel, char *buf)
{
const struct hv_ring_buffer_info *rbi = &channel->outbound;
+ if (!rbi->ring_buffer)
+ return -EINVAL;
+
return sprintf(buf, "%u\n", rbi->ring_buffer->interrupt_mask);
}
static VMBUS_CHAN_ATTR_RO(out_mask);
@@ -1457,6 +1457,9 @@ static ssize_t in_mask_show(const struct vmbus_channel *channel, char *buf)
{
const struct hv_ring_buffer_info *rbi = &channel->inbound;
+ if (!rbi->ring_buffer)
+ return -EINVAL;
+
return sprintf(buf, "%u\n", rbi->ring_buffer->interrupt_mask);
}
static VMBUS_CHAN_ATTR_RO(in_mask);
@@ -1465,6 +1468,9 @@ static ssize_t read_avail_show(const struct vmbus_channel *channel, char *buf)
{
const struct hv_ring_buffer_info *rbi = &channel->inbound;
+ if (!rbi->ring_buffer)
+ return -EINVAL;
+
return sprintf(buf, "%u\n", hv_get_bytes_to_read(rbi));
}
static VMBUS_CHAN_ATTR_RO(read_avail);
@@ -1473,6 +1479,9 @@ static ssize_t write_avail_show(const struct vmbus_channel *channel, char *buf)
{
const struct hv_ring_buffer_info *rbi = &channel->outbound;
+ if (!rbi->ring_buffer)
+ return -EINVAL;
+
return sprintf(buf, "%u\n", hv_get_bytes_to_write(rbi));
}
static VMBUS_CHAN_ATTR_RO(write_avail);