[PATCH] hv: vmbus: Convert sprintf() family to sysfs_emit() family

From: Li Zhijian
Date: Mon Mar 18 2024 - 23:44:17 EST

Per filesystems/sysfs.rst, show() should only use sysfs_emit()
or sysfs_emit_at() when formatting the value to be returned to user space.

coccinelle complains that there are still a couple of functions that use
snprintf(). Convert them to sysfs_emit().

sprintf() and scnprintf() will be converted as well if they have.

Generally, this patch is generated by
make coccicheck M=<path/to/file> MODE=patch \
COCCI=scripts/coccinelle/api/device_attr_show.cocci

No functional change intended

CC: "K. Y. Srinivasan" <kys@xxxxxxxxxxxxx>
CC: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
CC: Wei Liu <wei.liu@xxxxxxxxxx>
CC: Dexuan Cui <decui@xxxxxxxxxxxxx>
CC: linux-hyperv@xxxxxxxxxxxxxxx
Signed-off-by: Li Zhijian <lizhijian@xxxxxxxxxxx>
---
This is a part of the work "Fix coccicheck device_attr_show warnings"[1]
Split them per subsystem so that the maintainer can review it easily
[1] https://lore.kernel.org/lkml/20240116041129.3937800-1-lizhijian@xxxxxxxxxxx/
---
drivers/hv/vmbus_drv.c | 94 +++++++++++++++++++-----------------------
1 file changed, 42 insertions(+), 52 deletions(-)

diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index 7f7965f3d187..121f1ab32b51 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -131,7 +131,7 @@ static ssize_t id_show(struct device *dev, struct device_attribute *dev_attr,

if (!hv_dev->channel)
return -ENODEV;
- return sprintf(buf, "%d\n", hv_dev->channel->offermsg.child_relid);
+ return sysfs_emit(buf, "%d\n", hv_dev->channel->offermsg.child_relid);
}
static DEVICE_ATTR_RO(id);

@@ -142,7 +142,7 @@ static ssize_t state_show(struct device *dev, struct device_attribute *dev_attr,

if (!hv_dev->channel)
return -ENODEV;
- return sprintf(buf, "%d\n", hv_dev->channel->state);
+ return sysfs_emit(buf, "%d\n", hv_dev->channel->state);
}
static DEVICE_ATTR_RO(state);

@@ -153,7 +153,7 @@ static ssize_t monitor_id_show(struct device *dev,

if (!hv_dev->channel)
return -ENODEV;
- return sprintf(buf, "%d\n", hv_dev->channel->offermsg.monitorid);
+ return sysfs_emit(buf, "%d\n", hv_dev->channel->offermsg.monitorid);
}
static DEVICE_ATTR_RO(monitor_id);

@@ -164,8 +164,8 @@ static ssize_t class_id_show(struct device *dev,

if (!hv_dev->channel)
return -ENODEV;
- return sprintf(buf, "{%pUl}\n",
- &hv_dev->channel->offermsg.offer.if_type);
+ return sysfs_emit(buf, "{%pUl}\n",
+ &hv_dev->channel->offermsg.offer.if_type);
}
static DEVICE_ATTR_RO(class_id);

@@ -176,8 +176,8 @@ static ssize_t device_id_show(struct device *dev,

if (!hv_dev->channel)
return -ENODEV;
- return sprintf(buf, "{%pUl}\n",
- &hv_dev->channel->offermsg.offer.if_instance);
+ return sysfs_emit(buf, "{%pUl}\n",
+ &hv_dev->channel->offermsg.offer.if_instance);
}
static DEVICE_ATTR_RO(device_id);

@@ -186,7 +186,7 @@ static ssize_t modalias_show(struct device *dev,
{
struct hv_device *hv_dev = device_to_hv_device(dev);

- return sprintf(buf, "vmbus:%*phN\n", UUID_SIZE, &hv_dev->dev_type);
+ return sysfs_emit(buf, "vmbus:%*phN\n", UUID_SIZE, &hv_dev->dev_type);
}
static DEVICE_ATTR_RO(modalias);

@@ -199,7 +199,7 @@ static ssize_t numa_node_show(struct device *dev,
if (!hv_dev->channel)
return -ENODEV;

- return sprintf(buf, "%d\n", cpu_to_node(hv_dev->channel->target_cpu));
+ return sysfs_emit(buf, "%d\n", cpu_to_node(hv_dev->channel->target_cpu));
}
static DEVICE_ATTR_RO(numa_node);
#endif
@@ -212,9 +212,8 @@ static ssize_t server_monitor_pending_show(struct device *dev,

if (!hv_dev->channel)
return -ENODEV;
- return sprintf(buf, "%d\n",
- channel_pending(hv_dev->channel,
- vmbus_connection.monitor_pages[0]));
+ return sysfs_emit(buf, "%d\n", channel_pending(hv_dev->channel,
+ vmbus_connection.monitor_pages[0]));
}
static DEVICE_ATTR_RO(server_monitor_pending);

@@ -226,9 +225,8 @@ static ssize_t client_monitor_pending_show(struct device *dev,

if (!hv_dev->channel)
return -ENODEV;
- return sprintf(buf, "%d\n",
- channel_pending(hv_dev->channel,
- vmbus_connection.monitor_pages[1]));
+ return sysfs_emit(buf, "%d\n", channel_pending(hv_dev->channel,
+ vmbus_connection.monitor_pages[1]));
}
static DEVICE_ATTR_RO(client_monitor_pending);

@@ -240,9 +238,8 @@ static ssize_t server_monitor_latency_show(struct device *dev,

if (!hv_dev->channel)
return -ENODEV;
- return sprintf(buf, "%d\n",
- channel_latency(hv_dev->channel,
- vmbus_connection.monitor_pages[0]));
+ return sysfs_emit(buf, "%d\n", channel_latency(hv_dev->channel,
+ vmbus_connection.monitor_pages[0]));
}
static DEVICE_ATTR_RO(server_monitor_latency);

@@ -254,9 +251,8 @@ static ssize_t client_monitor_latency_show(struct device *dev,

if (!hv_dev->channel)
return -ENODEV;
- return sprintf(buf, "%d\n",
- channel_latency(hv_dev->channel,
- vmbus_connection.monitor_pages[1]));
+ return sysfs_emit(buf, "%d\n", channel_latency(hv_dev->channel,
+ vmbus_connection.monitor_pages[1]));
}
static DEVICE_ATTR_RO(client_monitor_latency);

@@ -268,9 +264,8 @@ static ssize_t server_monitor_conn_id_show(struct device *dev,

if (!hv_dev->channel)
return -ENODEV;
- return sprintf(buf, "%d\n",
- channel_conn_id(hv_dev->channel,
- vmbus_connection.monitor_pages[0]));
+ return sysfs_emit(buf, "%d\n", channel_conn_id(hv_dev->channel,
+ vmbus_connection.monitor_pages[0]));
}
static DEVICE_ATTR_RO(server_monitor_conn_id);

@@ -282,9 +277,8 @@ static ssize_t client_monitor_conn_id_show(struct device *dev,

if (!hv_dev->channel)
return -ENODEV;
- return sprintf(buf, "%d\n",
- channel_conn_id(hv_dev->channel,
- vmbus_connection.monitor_pages[1]));
+ return sysfs_emit(buf, "%d\n", channel_conn_id(hv_dev->channel,
+ vmbus_connection.monitor_pages[1]));
}
static DEVICE_ATTR_RO(client_monitor_conn_id);

@@ -303,7 +297,7 @@ static ssize_t out_intr_mask_show(struct device *dev,
if (ret < 0)
return ret;

- return sprintf(buf, "%d\n", outbound.current_interrupt_mask);
+ return sysfs_emit(buf, "%d\n", outbound.current_interrupt_mask);
}
static DEVICE_ATTR_RO(out_intr_mask);

@@ -321,7 +315,7 @@ static ssize_t out_read_index_show(struct device *dev,
&outbound);
if (ret < 0)
return ret;
- return sprintf(buf, "%d\n", outbound.current_read_index);
+ return sysfs_emit(buf, "%d\n", outbound.current_read_index);
}
static DEVICE_ATTR_RO(out_read_index);

@@ -340,7 +334,7 @@ static ssize_t out_write_index_show(struct device *dev,
&outbound);
if (ret < 0)
return ret;
- return sprintf(buf, "%d\n", outbound.current_write_index);
+ return sysfs_emit(buf, "%d\n", outbound.current_write_index);
}
static DEVICE_ATTR_RO(out_write_index);

@@ -359,7 +353,7 @@ static ssize_t out_read_bytes_avail_show(struct device *dev,
&outbound);
if (ret < 0)
return ret;
- return sprintf(buf, "%d\n", outbound.bytes_avail_toread);
+ return sysfs_emit(buf, "%d\n", outbound.bytes_avail_toread);
}
static DEVICE_ATTR_RO(out_read_bytes_avail);

@@ -378,7 +372,7 @@ static ssize_t out_write_bytes_avail_show(struct device *dev,
&outbound);
if (ret < 0)
return ret;
- return sprintf(buf, "%d\n", outbound.bytes_avail_towrite);
+ return sysfs_emit(buf, "%d\n", outbound.bytes_avail_towrite);
}
static DEVICE_ATTR_RO(out_write_bytes_avail);

@@ -396,7 +390,7 @@ static ssize_t in_intr_mask_show(struct device *dev,
if (ret < 0)
return ret;

- return sprintf(buf, "%d\n", inbound.current_interrupt_mask);
+ return sysfs_emit(buf, "%d\n", inbound.current_interrupt_mask);
}
static DEVICE_ATTR_RO(in_intr_mask);

@@ -414,7 +408,7 @@ static ssize_t in_read_index_show(struct device *dev,
if (ret < 0)
return ret;

- return sprintf(buf, "%d\n", inbound.current_read_index);
+ return sysfs_emit(buf, "%d\n", inbound.current_read_index);
}
static DEVICE_ATTR_RO(in_read_index);

@@ -432,7 +426,7 @@ static ssize_t in_write_index_show(struct device *dev,
if (ret < 0)
return ret;

- return sprintf(buf, "%d\n", inbound.current_write_index);
+ return sysfs_emit(buf, "%d\n", inbound.current_write_index);
}
static DEVICE_ATTR_RO(in_write_index);

@@ -451,7 +445,7 @@ static ssize_t in_read_bytes_avail_show(struct device *dev,
if (ret < 0)
return ret;

- return sprintf(buf, "%d\n", inbound.bytes_avail_toread);
+ return sysfs_emit(buf, "%d\n", inbound.bytes_avail_toread);
}
static DEVICE_ATTR_RO(in_read_bytes_avail);

@@ -470,7 +464,7 @@ static ssize_t in_write_bytes_avail_show(struct device *dev,
if (ret < 0)
return ret;

- return sprintf(buf, "%d\n", inbound.bytes_avail_towrite);
+ return sysfs_emit(buf, "%d\n", inbound.bytes_avail_towrite);
}
static DEVICE_ATTR_RO(in_write_bytes_avail);

@@ -480,7 +474,7 @@ static ssize_t channel_vp_mapping_show(struct device *dev,
{
struct hv_device *hv_dev = device_to_hv_device(dev);
struct vmbus_channel *channel = hv_dev->channel, *cur_sc;
- int buf_size = PAGE_SIZE, n_written, tot_written;
+ int n_written;
struct list_head *cur;

if (!channel)
@@ -488,25 +482,21 @@ static ssize_t channel_vp_mapping_show(struct device *dev,

mutex_lock(&vmbus_connection.channel_mutex);

- tot_written = snprintf(buf, buf_size, "%u:%u\n",
- channel->offermsg.child_relid, channel->target_cpu);
+ n_written = sysfs_emit(buf, "%u:%u\n",
+ channel->offermsg.child_relid,
+ channel->target_cpu);

list_for_each(cur, &channel->sc_list) {
- if (tot_written >= buf_size - 1)
- break;

cur_sc = list_entry(cur, struct vmbus_channel, sc_list);
- n_written = scnprintf(buf + tot_written,
- buf_size - tot_written,
- "%u:%u\n",
- cur_sc->offermsg.child_relid,
- cur_sc->target_cpu);
- tot_written += n_written;
+ n_written += sysfs_emit_at(buf, n_written, "%u:%u\n",
+ cur_sc->offermsg.child_relid,
+ cur_sc->target_cpu);
}

mutex_unlock(&vmbus_connection.channel_mutex);

- return tot_written;
+ return n_written;
}
static DEVICE_ATTR_RO(channel_vp_mapping);

@@ -516,7 +506,7 @@ static ssize_t vendor_show(struct device *dev,
{
struct hv_device *hv_dev = device_to_hv_device(dev);

- return sprintf(buf, "0x%x\n", hv_dev->vendor_id);
+ return sysfs_emit(buf, "0x%x\n", hv_dev->vendor_id);
}
static DEVICE_ATTR_RO(vendor);

@@ -526,7 +516,7 @@ static ssize_t device_show(struct device *dev,
{
struct hv_device *hv_dev = device_to_hv_device(dev);

- return sprintf(buf, "0x%x\n", hv_dev->device_id);
+ return sysfs_emit(buf, "0x%x\n", hv_dev->device_id);
}
static DEVICE_ATTR_RO(device);

@@ -551,7 +541,7 @@ static ssize_t driver_override_show(struct device *dev,
ssize_t len;

device_lock(dev);
- len = snprintf(buf, PAGE_SIZE, "%s\n", hv_dev->driver_override);
+ len = sysfs_emit(buf, "%s\n", hv_dev->driver_override);
device_unlock(dev);

return len;
--
2.29.2