[PATCH 2/5] scsi: 3w-sas: Remove snprintf() from sysfs call-backs and replace with sysfs_emit()

From: Lee Jones
Date: Thu Jan 11 2024 - 08:18:20 EST


Since snprintf() has the documented, but still rather strange trait of
returning the length of the data that *would have been* written to the
array if space were available, rather than the arguably more useful
length of data *actually* written, it is usually considered wise to use
something else instead in order to avoid confusion.

In the case of sysfs call-backs, new wrappers exist that do just that.

Link: https://lwn.net/Articles/69419/
Link: https://github.com/KSPP/linux/issues/105
Cc: Adam Radford <aradford@xxxxxxxxx>
Signed-off-by: Lee Jones <lee@xxxxxxxxxx>
---
drivers/scsi/3w-sas.c | 36 ++++++++++++++++++------------------
1 file changed, 18 insertions(+), 18 deletions(-)

diff --git a/drivers/scsi/3w-sas.c b/drivers/scsi/3w-sas.c
index 9bdb75dfdcd7c..caa6713a62a44 100644
--- a/drivers/scsi/3w-sas.c
+++ b/drivers/scsi/3w-sas.c
@@ -166,24 +166,24 @@ static ssize_t twl_show_stats(struct device *dev,
ssize_t len;

spin_lock_irqsave(tw_dev->host->host_lock, flags);
- len = snprintf(buf, PAGE_SIZE, "3w-sas Driver version: %s\n"
- "Current commands posted: %4d\n"
- "Max commands posted: %4d\n"
- "Last sgl length: %4d\n"
- "Max sgl length: %4d\n"
- "Last sector count: %4d\n"
- "Max sector count: %4d\n"
- "SCSI Host Resets: %4d\n"
- "AEN's: %4d\n",
- TW_DRIVER_VERSION,
- tw_dev->posted_request_count,
- tw_dev->max_posted_request_count,
- tw_dev->sgl_entries,
- tw_dev->max_sgl_entries,
- tw_dev->sector_count,
- tw_dev->max_sector_count,
- tw_dev->num_resets,
- tw_dev->aen_count);
+ len = sysfs_emit(buf, "3w-sas Driver version: %s\n"
+ "Current commands posted: %4d\n"
+ "Max commands posted: %4d\n"
+ "Last sgl length: %4d\n"
+ "Max sgl length: %4d\n"
+ "Last sector count: %4d\n"
+ "Max sector count: %4d\n"
+ "SCSI Host Resets: %4d\n"
+ "AEN's: %4d\n",
+ TW_DRIVER_VERSION,
+ tw_dev->posted_request_count,
+ tw_dev->max_posted_request_count,
+ tw_dev->sgl_entries,
+ tw_dev->max_sgl_entries,
+ tw_dev->sector_count,
+ tw_dev->max_sector_count,
+ tw_dev->num_resets,
+ tw_dev->aen_count);
spin_unlock_irqrestore(tw_dev->host->host_lock, flags);
return len;
} /* End twl_show_stats() */
--
2.43.0.275.g3460e3d667-goog