#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,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct ctl_table ipc_table;
+ size_t lenp_bef = *lenp;
+ int rc;
+
+ 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 by hand. Disable its
+ * automatic adjustment. This simply requires unregistering
+ * the notifiers that trigger recalculation.
+ */
+ unregister_ipcns_notifier(current->nsproxy->ipc_ns);
+
+ return rc;
}
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);
}
-#else
-#define proc_ipc_doulongvec_minmax NULL
-#define proc_ipc_dointvec 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,
- void __user *oldval, size_t __user *oldlenp,
- void __user *newval, size_t newlen)
+/*
+ * 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)
{
- size_t len;
- void *data;
-
- /* Get out of I don't have a variable */
- if (!table->data || !table->maxlen)
- return -ENOTDIR;
-
- data = get_ipc(table);
- if (!data)
- return -ENOTDIR;
-
- if (oldval && oldlenp) {
- if (get_user(len, oldlenp))
- return -EFAULT;
- if (len) {
- if (len > table->maxlen)
- len = table->maxlen;
- if (copy_to_user(oldval, data, len))
- return -EFAULT;
- if (put_user(len, oldlenp))
- return -EFAULT;
- }
+ 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);
}
+}
- if (newval && newlen) {
- if (newlen > table->maxlen)
- newlen = table->maxlen;
+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;
- if (copy_from_user(data, newval, newlen))
- return -EFAULT;
+ 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 1;
+
+ return rc;
}
+
#else
-#define sysctl_ipc_data NULL
+#define proc_ipc_doulongvec_minmax NULL
+#define proc_ipc_dointvec NULL
+#define proc_ipc_callback_dointvec NULL
+#define proc_ipcauto_dointvec_minmax NULL
#endif
+static int zero;
+static int one = 1;
+
static struct ctl_table ipc_kern_table[] = {
{
- .ctl_name = KERN_SHMMAX,
.procname = "shmmax",
.data = &init_ipc_ns.shm_ctlmax,
.maxlen = sizeof (init_ipc_ns.shm_ctlmax),
.mode = 0644,
.proc_handler = proc_ipc_doulongvec_minmax,
- .strategy = sysctl_ipc_data,
},
{
- .ctl_name = KERN_SHMALL,
.procname = "shmall",
.data = &init_ipc_ns.shm_ctlall,
.maxlen = sizeof (init_ipc_ns.shm_ctlall),
.mode = 0644,
.proc_handler = proc_ipc_doulongvec_minmax,
- .strategy = sysctl_ipc_data,
},
{
- .ctl_name = KERN_SHMMNI,
.procname = "shmmni",
.data = &init_ipc_ns.shm_ctlmni,
.maxlen = sizeof (init_ipc_ns.shm_ctlmni),
.mode = 0644,
.proc_handler = proc_ipc_dointvec,
- .strategy = sysctl_ipc_data,
},
{
- .ctl_name = KERN_MSGMAX,
.procname = "msgmax",
.data = &init_ipc_ns.msg_ctlmax,
.maxlen = sizeof (init_ipc_ns.msg_ctlmax),
.mode = 0644,
.proc_handler = proc_ipc_dointvec,
- .strategy = sysctl_ipc_data,
},
{
- .ctl_name = KERN_MSGMNI,
.procname = "msgmni",
.data = &init_ipc_ns.msg_ctlmni,
.maxlen = sizeof (init_ipc_ns.msg_ctlmni),
.mode = 0644,
- .proc_handler = proc_ipc_dointvec,
- .strategy = sysctl_ipc_data,
+ .proc_handler = proc_ipc_callback_dointvec,
},
{
- .ctl_name = KERN_MSGMNB,
.procname = "msgmnb",
.data = &init_ipc_ns.msg_ctlmnb,
.maxlen = sizeof (init_ipc_ns.msg_ctlmnb),
.mode = 0644,
.proc_handler = proc_ipc_dointvec,
- .strategy = sysctl_ipc_data,
},
{
- .ctl_name = KERN_SEM,
.procname = "sem",
.data = &init_ipc_ns.sem_ctls,
.maxlen = 4*sizeof (int),
.mode = 0644,
.proc_handler = proc_ipc_dointvec,
- .strategy = sysctl_ipc_data,
+ },
+ {
+ .procname = "auto_msgmni",
+ .data = &init_ipc_ns.auto_msgmni,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_ipcauto_dointvec_minmax,
+ .extra1 = &zero,
+ .extra2 = &one,
},
{}
};
static struct ctl_table ipc_root_table[] = {
{
- .ctl_name = CTL_KERN,
.procname = "kernel",
.mode = 0555,
.child = ipc_kern_table,
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff