[PATCH 1/3] Sysctl: merge equal proc_sys_read and proc_sys_write

Pavel Emelyanov
2008-02-27T13:49:29Z

These ->read and ->write callbacks act in a very similar way, so
merge these paths to reduce the number of places to patch later
and shrink the .text size (a bit).

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
---
fs/proc/proc_sysctl.c | 50 ++++++++++--------------------------------------
1 files changed, 11 insertions(+), 39 deletions(-)

diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index 614c34b..5e31585 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -165,8 +165,8 @@ out:
return err;
}

-static ssize_t proc_sys_read(struct file *filp, char __user *buf,
- size_t count, loff_t *ppos)
+static ssize_t proc_sys_call_handler(struct file *filp, void __user *buf,
+ size_t count, loff_t *ppos, int write)
{
struct dentry *dentry = filp->f_dentry;
struct ctl_table_header *head;
@@ -190,12 +190,12 @@ static ssize_t proc_sys_read(struct file *filp, char __user *buf,
* and won't be until we finish.
*/
error = -EPERM;
- if (sysctl_perm(table, MAY_READ))
+ if (sysctl_perm(table, write ? MAY_WRITE : MAY_READ))
goto out;

/* careful: calling conventions are nasty here */
res = count;
- error = table->proc_handler(table, 0, filp, buf, &res, ppos);
+ error = table->proc_handler(table, write, filp, buf, &res, ppos);
if (!error)
error = res;
out:
@@ -204,44 +204,16 @@ out:
return error;
}

-static ssize_t proc_sys_write(struct file *filp, const char __user *buf,
+static ssize_t proc_sys_read(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
- struct dentry *dentry = filp->f_dentry;
- struct ctl_table_header *head;
- struct ctl_table *table;
- ssize_t error;
- size_t res;
-
- table = do_proc_sys_lookup(dentry->d_parent, &dentry->d_name, &head);
- /* Has the sysctl entry disappeared on us? */
- error = -ENOENT;
- if (!table)
- goto out;
-
- /* Has the sysctl entry been replaced by a directory? */
- error = -EISDIR;
- if (!table->proc_handler)
- goto out;
-
- /*
- * At this point we know that the sysctl was not unregistered
- * and won't be until we finish.
- */
- error = -EPERM;
- if (sysctl_perm(table, MAY_WRITE))
- goto out;
-
- /* careful: calling conventions are nasty here */
- res = count;
- error = table->proc_handler(table, 1, filp, (char __user *)buf,
- &res, ppos);
- if (!error)
- error = res;
-out:
- sysctl_head_finish(head);
+ return proc_sys_call_handler(filp, (void __user *)buf, count, ppos, 0);
+}

- return error;
+static ssize_t proc_sys_write(struct file *filp, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ return proc_sys_call_handler(filp, (void __user *)buf, count, ppos, 1);
}

--
1.5.3.4