bcache: Convert to use sysfs_emit()/sysfs_emit_at() APIs

Follow the advice of the Documentation/filesystems/sysfs.rst and show()
should only use sysfs_emit() or sysfs_emit_at() when formatting the
value to be returned to user space.

Signed-off-by: ye xingchen <ye.xingchen@zte.com.cn>
Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20230615121223.22502-2-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c
index c6f6770..0e2c188 100644 (file)
--- a/drivers/md/bcache/sysfs.c
+++ b/drivers/md/bcache/sysfs.c
@@ -1111,26 +1111,25 @@ SHOW(__bch_cache)
 
                vfree(p);
 
-               ret = scnprintf(buf, PAGE_SIZE,
-                               "Unused:                %zu%%\n"
-                               "Clean:         %zu%%\n"
-                               "Dirty:         %zu%%\n"
-                               "Metadata:      %zu%%\n"
-                               "Average:       %llu\n"
-                               "Sectors per Q: %zu\n"
-                               "Quantiles:     [",
-                               unused * 100 / (size_t) ca->sb.nbuckets,
-                               available * 100 / (size_t) ca->sb.nbuckets,
-                               dirty * 100 / (size_t) ca->sb.nbuckets,
-                               meta * 100 / (size_t) ca->sb.nbuckets, sum,
-                               n * ca->sb.bucket_size / (ARRAY_SIZE(q) + 1));
+               ret = sysfs_emit(buf,
+                                "Unused:               %zu%%\n"
+                                "Clean:                %zu%%\n"
+                                "Dirty:                %zu%%\n"
+                                "Metadata:     %zu%%\n"
+                                "Average:      %llu\n"
+                                "Sectors per Q:        %zu\n"
+                                "Quantiles:    [",
+                                unused * 100 / (size_t) ca->sb.nbuckets,
+                                available * 100 / (size_t) ca->sb.nbuckets,
+                                dirty * 100 / (size_t) ca->sb.nbuckets,
+                                meta * 100 / (size_t) ca->sb.nbuckets, sum,
+                                n * ca->sb.bucket_size / (ARRAY_SIZE(q) + 1));
 
                for (i = 0; i < ARRAY_SIZE(q); i++)
-                       ret += scnprintf(buf + ret, PAGE_SIZE - ret,
-                                        "%u ", q[i]);
+                       ret += sysfs_emit_at(buf, ret, "%u ", q[i]);
                ret--;
 
-               ret += scnprintf(buf + ret, PAGE_SIZE - ret, "]\n");
+               ret += sysfs_emit_at(buf, ret, "]\n");
 
                return ret;
        }