#include <linux/syscalls.h>
#include <linux/audit.h>
#include <linux/seq_file.h>
-#include <linux/mutex.h>
+#include <linux/rwsem.h>
#include <linux/nsproxy.h>
+#include <linux/ipc_namespace.h>
#include <asm/current.h>
#include <asm/uaccess.h>
#define SEARCH_NOTEQUAL 3
#define SEARCH_LESSEQUAL 4
-static atomic_t msg_bytes = ATOMIC_INIT(0);
-static atomic_t msg_hdrs = ATOMIC_INIT(0);
-
static struct ipc_ids init_msg_ids;
#define msg_ids(ns) (*((ns)->ids[IPC_MSG_IDS]))
#define msg_unlock(msq) ipc_unlock(&(msq)->q_perm)
-#define msg_buildid(ns, id, seq) \
- ipc_buildid(&msg_ids(ns), id, seq)
+#define msg_buildid(id, seq) ipc_buildid(id, seq)
static void freeque(struct ipc_namespace *, struct msg_queue *);
static int newque(struct ipc_namespace *, struct ipc_params *);
ns->msg_ctlmax = MSGMAX;
ns->msg_ctlmnb = MSGMNB;
ns->msg_ctlmni = MSGMNI;
+ atomic_set(&ns->msg_bytes, 0);
+ atomic_set(&ns->msg_hdrs, 0);
ipc_init_ids(ids);
}
+#ifdef CONFIG_IPC_NS
int msg_init_ns(struct ipc_namespace *ns)
{
struct ipc_ids *ids;
void msg_exit_ns(struct ipc_namespace *ns)
{
struct msg_queue *msq;
+ struct kern_ipc_perm *perm;
int next_id;
int total, in_use;
- mutex_lock(&msg_ids(ns).mutex);
+ down_write(&msg_ids(ns).rw_mutex);
in_use = msg_ids(ns).in_use;
for (total = 0, next_id = 0; total < in_use; next_id++) {
- msq = idr_find(&msg_ids(ns).ipcs_idr, next_id);
- if (msq == NULL)
+ perm = idr_find(&msg_ids(ns).ipcs_idr, next_id);
+ if (perm == NULL)
continue;
- ipc_lock_by_ptr(&msq->q_perm);
+ ipc_lock_by_ptr(perm);
+ msq = container_of(perm, struct msg_queue, q_perm);
freeque(ns, msq);
total++;
}
- mutex_unlock(&msg_ids(ns).mutex);
+
+ up_write(&msg_ids(ns).rw_mutex);
kfree(ns->ids[IPC_MSG_IDS]);
ns->ids[IPC_MSG_IDS] = NULL;
}
+#endif
void __init msg_init(void)
{
IPC_MSG_IDS, sysvipc_msg_proc_show);
}
+/*
+ * This routine is called in the paths where the rw_mutex is held to protect
+ * access to the idr tree.
+ */
+static inline struct msg_queue *msg_lock_check_down(struct ipc_namespace *ns,
+ int id)
+{
+ struct kern_ipc_perm *ipcp = ipc_lock_check_down(&msg_ids(ns), id);
+
+ if (IS_ERR(ipcp))
+ return (struct msg_queue *)ipcp;
+
+ return container_of(ipcp, struct msg_queue, q_perm);
+}
+
+/*
+ * msg_lock_(check_) routines are called in the paths where the rw_mutex
+ * is not held.
+ */
static inline struct msg_queue *msg_lock(struct ipc_namespace *ns, int id)
{
struct kern_ipc_perm *ipcp = ipc_lock(&msg_ids(ns), id);
+ if (IS_ERR(ipcp))
+ return (struct msg_queue *)ipcp;
+
return container_of(ipcp, struct msg_queue, q_perm);
}
{
struct kern_ipc_perm *ipcp = ipc_lock_check(&msg_ids(ns), id);
+ if (IS_ERR(ipcp))
+ return (struct msg_queue *)ipcp;
+
return container_of(ipcp, struct msg_queue, q_perm);
}
* @ns: namespace
* @params: ptr to the structure that contains the key and msgflg
*
- * Called with msg_ids.mutex held
+ * Called with msg_ids.rw_mutex held (writer)
*/
static int newque(struct ipc_namespace *ns, struct ipc_params *params)
{
* ipc_addid() locks msq
*/
id = ipc_addid(&msg_ids(ns), &msq->q_perm, ns->msg_ctlmni);
- if (id == -1) {
+ if (id < 0) {
security_msg_queue_free(msq);
ipc_rcu_putref(msq);
- return -ENOSPC;
+ return id;
}
- msq->q_perm.id = msg_buildid(ns, id, msq->q_perm.seq);
+ msq->q_perm.id = msg_buildid(id, msq->q_perm.seq);
msq->q_stime = msq->q_rtime = 0;
msq->q_ctime = get_seconds();
msq->q_cbytes = msq->q_qnum = 0;
* removes the message queue from message queue ID IDR, and cleans up all the
* messages associated with this queue.
*
- * msg_ids.mutex and the spinlock for this message queue are held
- * before freeque() is called. msg_ids.mutex remains locked on exit.
+ * msg_ids.rw_mutex (writer) and the spinlock for this message queue are held
+ * before freeque() is called. msg_ids.rw_mutex remains locked on exit.
*/
static void freeque(struct ipc_namespace *ns, struct msg_queue *msq)
{
struct msg_msg *msg = list_entry(tmp, struct msg_msg, m_list);
tmp = tmp->next;
- atomic_dec(&msg_hdrs);
+ atomic_dec(&ns->msg_hdrs);
free_msg(msg);
}
- atomic_sub(msq->q_cbytes, &msg_bytes);
+ atomic_sub(msq->q_cbytes, &ns->msg_bytes);
security_msg_queue_free(msq);
ipc_rcu_putref(msq);
}
/*
- * Called with msg_ids.mutex and ipcp locked.
+ * Called with msg_ids.rw_mutex and ipcp locked.
*/
static inline int msg_security(struct kern_ipc_perm *ipcp, int msgflg)
{
msginfo.msgmnb = ns->msg_ctlmnb;
msginfo.msgssz = MSGSSZ;
msginfo.msgseg = MSGSEG;
- mutex_lock(&msg_ids(ns).mutex);
+ down_read(&msg_ids(ns).rw_mutex);
if (cmd == MSG_INFO) {
msginfo.msgpool = msg_ids(ns).in_use;
- msginfo.msgmap = atomic_read(&msg_hdrs);
- msginfo.msgtql = atomic_read(&msg_bytes);
+ msginfo.msgmap = atomic_read(&ns->msg_hdrs);
+ msginfo.msgtql = atomic_read(&ns->msg_bytes);
} else {
msginfo.msgmap = MSGMAP;
msginfo.msgpool = MSGPOOL;
msginfo.msgtql = MSGTQL;
}
max_id = ipc_get_maxid(&msg_ids(ns));
- mutex_unlock(&msg_ids(ns).mutex);
+ up_read(&msg_ids(ns).rw_mutex);
if (copy_to_user(buf, &msginfo, sizeof(struct msginfo)))
return -EFAULT;
return (max_id < 0) ? 0 : max_id;
return -EINVAL;
}
- mutex_lock(&msg_ids(ns).mutex);
- msq = msg_lock_check(ns, msqid);
+ down_write(&msg_ids(ns).rw_mutex);
+ msq = msg_lock_check_down(ns, msqid);
if (IS_ERR(msq)) {
err = PTR_ERR(msq);
goto out_up;
}
err = 0;
out_up:
- mutex_unlock(&msg_ids(ns).mutex);
+ up_write(&msg_ids(ns).rw_mutex);
return err;
out_unlock_up:
msg_unlock(msq);
list_add_tail(&msg->m_list, &msq->q_messages);
msq->q_cbytes += msgsz;
msq->q_qnum++;
- atomic_add(msgsz, &msg_bytes);
- atomic_inc(&msg_hdrs);
+ atomic_add(msgsz, &ns->msg_bytes);
+ atomic_inc(&ns->msg_hdrs);
}
err = 0;
msq->q_rtime = get_seconds();
msq->q_lrpid = task_tgid_vnr(current);
msq->q_cbytes -= msg->m_ts;
- atomic_sub(msg->m_ts, &msg_bytes);
- atomic_dec(&msg_hdrs);
+ atomic_sub(msg->m_ts, &ns->msg_bytes);
+ atomic_dec(&ns->msg_hdrs);
ss_wakeup(&msq->q_senders, 0);
msg_unlock(msq);
break;
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff