#include <linux/sysctl.h>
#include <linux/uaccess.h>
#include <linux/ipc_namespace.h>
+#include <linux/msg.h>
+#include "util.h"
static void *get_ipc(ctl_table *table)
{
return which;
}
-#ifdef CONFIG_PROC_FS
-static int proc_ipc_dointvec(ctl_table *table, int write, struct file *filp,
+#ifdef CONFIG_PROC_SYSCTL
+static int proc_ipc_dointvec(ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
struct ctl_table ipc_table;
memcpy(&ipc_table, table, sizeof(ipc_table));
ipc_table.data = get_ipc(table);
- return proc_dointvec(&ipc_table, write, filp, buffer, lenp, ppos);
+ return proc_dointvec(&ipc_table, write, buffer, lenp, ppos);
}
static int proc_ipc_callback_dointvec(ctl_table *table, int write,
- struct file *filp, void __user *buffer, size_t *lenp, loff_t *ppos)
+ void __user *buffer, size_t *lenp, loff_t *ppos)
{
+ struct ctl_table ipc_table;
size_t lenp_bef = *lenp;
int rc;
- rc = proc_ipc_dointvec(table, write, filp, buffer, lenp, ppos);
+ memcpy(&ipc_table, table, sizeof(ipc_table));
+ ipc_table.data = get_ipc(table);
+
+ rc = proc_dointvec(&ipc_table, write, buffer, lenp, ppos);
if (write && !rc && lenp_bef == *lenp)
/*
- * Tunable has successfully been changed from userland:
- * disable its automatic recomputing.
+ * Tunable has successfully been changed by hand. Disable its
+ * automatic adjustment. This simply requires unregistering
+ * the notifiers that trigger recalculation.
*/
unregister_ipcns_notifier(current->nsproxy->ipc_ns);
}
static int proc_ipc_doulongvec_minmax(ctl_table *table, int write,
- struct file *filp, void __user *buffer, size_t *lenp, loff_t *ppos)
+ void __user *buffer, size_t *lenp, loff_t *ppos)
{
struct ctl_table ipc_table;
memcpy(&ipc_table, table, sizeof(ipc_table));
ipc_table.data = get_ipc(table);
- return proc_doulongvec_minmax(&ipc_table, write, filp, buffer,
+ return proc_doulongvec_minmax(&ipc_table, write, buffer,
lenp, ppos);
}
+/*
+ * Routine that is called when the file "auto_msgmni" has successfully been
+ * written.
+ * Two values are allowed:
+ * 0: unregister msgmni's callback routine from the ipc namespace notifier
+ * chain. This means that msgmni won't be recomputed anymore upon memory
+ * add/remove or ipc namespace creation/removal.
+ * 1: register back the callback routine.
+ */
+static void ipc_auto_callback(int val)
+{
+ if (!val)
+ unregister_ipcns_notifier(current->nsproxy->ipc_ns);
+ else {
+ /*
+ * Re-enable automatic recomputing only if not already
+ * enabled.
+ */
+ recompute_msgmni(current->nsproxy->ipc_ns);
+ cond_register_ipcns_notifier(current->nsproxy->ipc_ns);
+ }
+}
+
+static int proc_ipcauto_dointvec_minmax(ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct ctl_table ipc_table;
+ size_t lenp_bef = *lenp;
+ int oldval;
+ int rc;
+
+ memcpy(&ipc_table, table, sizeof(ipc_table));
+ ipc_table.data = get_ipc(table);
+ oldval = *((int *)(ipc_table.data));
+
+ rc = proc_dointvec_minmax(&ipc_table, write, buffer, lenp, ppos);
+
+ if (write && !rc && lenp_bef == *lenp) {
+ int newval = *((int *)(ipc_table.data));
+ /*
+ * The file "auto_msgmni" has correctly been set.
+ * React by (un)registering the corresponding tunable, if the
+ * value has changed.
+ */
+ if (newval != oldval)
+ ipc_auto_callback(newval);
+ }
+
+ return rc;
+}
+
#else
#define proc_ipc_doulongvec_minmax NULL
#define proc_ipc_dointvec NULL
#define proc_ipc_callback_dointvec NULL
+#define proc_ipcauto_dointvec_minmax NULL
#endif
#ifdef CONFIG_SYSCTL_SYSCALL
/* The generic sysctl ipc data routine. */
-static int sysctl_ipc_data(ctl_table *table, int __user *name, int nlen,
+static int sysctl_ipc_data(ctl_table *table,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
return 1;
}
-static int sysctl_ipc_registered_data(ctl_table *table, int __user *name,
- int nlen, void __user *oldval, size_t __user *oldlenp,
+static int sysctl_ipc_registered_data(ctl_table *table,
+ void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen)
{
int rc;
- rc = sysctl_ipc_data(table, name, nlen, oldval, oldlenp, newval,
- newlen);
+ rc = sysctl_ipc_data(table, oldval, oldlenp, newval, newlen);
if (newval && newlen && rc > 0)
/*
- * Tunable has successfully been changed from userland:
- * disable its automatic recomputing.
+ * Tunable has successfully been changed from userland
*/
unregister_ipcns_notifier(current->nsproxy->ipc_ns);
#define sysctl_ipc_registered_data NULL
#endif
+static int zero;
+static int one = 1;
+
static struct ctl_table ipc_kern_table[] = {
{
.ctl_name = KERN_SHMMAX,
.proc_handler = proc_ipc_dointvec,
.strategy = sysctl_ipc_data,
},
+ {
+ .ctl_name = CTL_UNNUMBERED,
+ .procname = "auto_msgmni",
+ .data = &init_ipc_ns.auto_msgmni,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_ipcauto_dointvec_minmax,
+ .extra1 = &zero,
+ .extra2 = &one,
+ },
{}
};
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff