[PATCH 6/6] s390: simplify dynamic sysctl registration for appldata_register_ops
From: Luis Chamberlain
Date: Fri Mar 10 2023 - 18:46:08 EST
The routine appldata_register_ops() allocates a sysctl table
with 4 entries. The firsts one, ops->ctl_table[0] is the parent directory
with an empty entry following it, ops->ctl_table[1]. The next entry is
for the the ops->name and that is ops->ctl_table[2]. It needs an empty
entry following that, and that is ops->ctl_table[3]. And so hence the
kcalloc(4, sizeof(struct ctl_table), GFP_KERNEL).
We can simplify this considerably since sysctl_register("foo", table)
can create the parent directory for us if it does not exist. So we
can just remove the first two entries and move back the ops->name to
the first entry, and just use kcalloc(2, ...).
Signed-off-by: Luis Chamberlain <mcgrof@xxxxxxxxxx>
---
arch/s390/appldata/appldata_base.c | 18 +++++++-----------
1 file changed, 7 insertions(+), 11 deletions(-)
diff --git a/arch/s390/appldata/appldata_base.c b/arch/s390/appldata/appldata_base.c
index c593f2228083..a60c1e093039 100644
--- a/arch/s390/appldata/appldata_base.c
+++ b/arch/s390/appldata/appldata_base.c
@@ -351,7 +351,8 @@ int appldata_register_ops(struct appldata_ops *ops)
if (ops->size > APPLDATA_MAX_REC_SIZE)
return -EINVAL;
- ops->ctl_table = kcalloc(4, sizeof(struct ctl_table), GFP_KERNEL);
+ /* The last entry must be an empty one */
+ ops->ctl_table = kcalloc(2, sizeof(struct ctl_table), GFP_KERNEL);
if (!ops->ctl_table)
return -ENOMEM;
@@ -359,17 +360,12 @@ int appldata_register_ops(struct appldata_ops *ops)
list_add(&ops->list, &appldata_ops_list);
mutex_unlock(&appldata_ops_mutex);
- ops->ctl_table[0].procname = appldata_proc_name;
- ops->ctl_table[0].maxlen = 0;
- ops->ctl_table[0].mode = S_IRUGO | S_IXUGO;
- ops->ctl_table[0].child = &ops->ctl_table[2];
+ ops->ctl_table[0].procname = ops->name;
+ ops->ctl_table[0].mode = S_IRUGO | S_IWUSR;
+ ops->ctl_table[0].proc_handler = appldata_generic_handler;
+ ops->ctl_table[0].data = ops;
- ops->ctl_table[2].procname = ops->name;
- ops->ctl_table[2].mode = S_IRUGO | S_IWUSR;
- ops->ctl_table[2].proc_handler = appldata_generic_handler;
- ops->ctl_table[2].data = ops;
-
- ops->sysctl_header = register_sysctl_table(ops->ctl_table);
+ ops->sysctl_header = register_sysctl(appldata_proc_name, ops->ctl_table);
if (!ops->sysctl_header)
goto out;
return 0;
--
2.39.1