#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);
+#define msg_ids(ns) ((ns)->ids[IPC_MSG_IDS])
-static struct ipc_ids init_msg_ids;
-
-#define msg_ids(ns) (*((ns)->ids[IPC_MSG_IDS]))
-
-#define msg_lock(ns, id) ((struct msg_queue*)ipc_lock(&msg_ids(ns), id))
#define msg_unlock(msq) ipc_unlock(&(msq)->q_perm)
-#define msg_checkid(ns, msq, msgid) \
- ipc_checkid(&msg_ids(ns), &msq->q_perm, msgid)
-#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 void freeque(struct ipc_namespace *, struct kern_ipc_perm *);
static int newque(struct ipc_namespace *, struct ipc_params *);
#ifdef CONFIG_PROC_FS
static int sysvipc_msg_proc_show(struct seq_file *s, void *it);
#endif
-static void __msg_init_ns(struct ipc_namespace *ns, struct ipc_ids *ids)
+void msg_init_ns(struct ipc_namespace *ns)
{
- ns->ids[IPC_MSG_IDS] = ids;
ns->msg_ctlmax = MSGMAX;
ns->msg_ctlmnb = MSGMNB;
ns->msg_ctlmni = MSGMNI;
- ipc_init_ids(ids);
+ atomic_set(&ns->msg_bytes, 0);
+ atomic_set(&ns->msg_hdrs, 0);
+ ipc_init_ids(&ns->ids[IPC_MSG_IDS]);
}
-int msg_init_ns(struct ipc_namespace *ns)
+#ifdef CONFIG_IPC_NS
+void msg_exit_ns(struct ipc_namespace *ns)
{
- struct ipc_ids *ids;
-
- ids = kmalloc(sizeof(struct ipc_ids), GFP_KERNEL);
- if (ids == NULL)
- return -ENOMEM;
+ free_ipcs(ns, &msg_ids(ns), freeque);
+}
+#endif
- __msg_init_ns(ns, ids);
- return 0;
+void __init msg_init(void)
+{
+ msg_init_ns(&init_ipc_ns);
+ ipc_init_proc_interface("sysvipc/msg",
+ " key msqid perms cbytes qnum lspid lrpid uid gid cuid cgid stime rtime ctime\n",
+ IPC_MSG_IDS, sysvipc_msg_proc_show);
}
-void msg_exit_ns(struct ipc_namespace *ns)
+/*
+ * 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 msg_queue *msq;
- int next_id;
- int total, in_use;
+ struct kern_ipc_perm *ipcp = ipc_lock_check_down(&msg_ids(ns), id);
+
+ if (IS_ERR(ipcp))
+ return (struct msg_queue *)ipcp;
- mutex_lock(&msg_ids(ns).mutex);
+ return container_of(ipcp, struct msg_queue, q_perm);
+}
- in_use = msg_ids(ns).in_use;
+/*
+ * 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);
- for (total = 0, next_id = 0; total < in_use; next_id++) {
- msq = idr_find(&msg_ids(ns).ipcs_idr, next_id);
- if (msq == NULL)
- continue;
- ipc_lock_by_ptr(&msq->q_perm);
- freeque(ns, msq);
- total++;
- }
- mutex_unlock(&msg_ids(ns).mutex);
+ if (IS_ERR(ipcp))
+ return (struct msg_queue *)ipcp;
- kfree(ns->ids[IPC_MSG_IDS]);
- ns->ids[IPC_MSG_IDS] = NULL;
+ return container_of(ipcp, struct msg_queue, q_perm);
}
-void __init msg_init(void)
+static inline struct msg_queue *msg_lock_check(struct ipc_namespace *ns,
+ int id)
{
- __msg_init_ns(&init_ipc_ns, &init_msg_ids);
- ipc_init_proc_interface("sysvipc/msg",
- " key msqid perms cbytes qnum lspid lrpid uid gid cuid cgid stime rtime ctime\n",
- IPC_MSG_IDS, sysvipc_msg_proc_show);
+ 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);
}
static inline void msg_rmid(struct ipc_namespace *ns, struct msg_queue *s)
ipc_rmid(&msg_ids(ns), &s->q_perm);
}
+/**
+ * newque - Create a new msg queue
+ * @ns: namespace
+ * @params: ptr to the structure that contains the key and msgflg
+ *
+ * Called with msg_ids.rw_mutex held (writer)
+ */
static int newque(struct ipc_namespace *ns, struct ipc_params *params)
{
struct msg_queue *msq;
* 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;
/*
* freeque() wakes up waiters on the sender and receiver waiting queue,
- * removes the message queue from message queue ID
- * IDR, and cleans up all the messages associated with this queue.
+ * 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)
+static void freeque(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp)
{
struct list_head *tmp;
+ struct msg_queue *msq = container_of(ipcp, struct msg_queue, q_perm);
expunge_all(msq, -EIDRM);
ss_wakeup(&msq->q_senders, 1);
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);
}
-static inline int msg_security(void *msq, int msgflg)
+/*
+ * Called with msg_ids.rw_mutex and ipcp locked.
+ */
+static inline int msg_security(struct kern_ipc_perm *ipcp, int msgflg)
{
- return security_msg_queue_associate((struct msg_queue *) msq, msgflg);
+ struct msg_queue *msq = container_of(ipcp, struct msg_queue, q_perm);
+
+ return security_msg_queue_associate(msq, msgflg);
}
asmlinkage long sys_msgget(key_t key, 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;
if (!buf)
return -EFAULT;
- memset(&tbuf, 0, sizeof(tbuf));
-
- msq = msg_lock(ns, msqid);
- if (msq == NULL)
- return -EINVAL;
-
if (cmd == MSG_STAT) {
+ msq = msg_lock(ns, msqid);
+ if (IS_ERR(msq))
+ return PTR_ERR(msq);
success_return = msq->q_perm.id;
} else {
- err = -EIDRM;
- if (msg_checkid(ns, msq, msqid))
- goto out_unlock;
+ msq = msg_lock_check(ns, msqid);
+ if (IS_ERR(msq))
+ return PTR_ERR(msq);
success_return = 0;
}
err = -EACCES;
if (err)
goto out_unlock;
+ memset(&tbuf, 0, sizeof(tbuf));
+
kernel_to_ipc64_perm(&msq->q_perm, &tbuf.msg_perm);
tbuf.msg_stime = msq->q_stime;
tbuf.msg_rtime = msq->q_rtime;
return -EINVAL;
}
- mutex_lock(&msg_ids(ns).mutex);
- msq = msg_lock(ns, msqid);
- err = -EINVAL;
- if (msq == NULL)
+ 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 = -EIDRM;
- if (msg_checkid(ns, msq, msqid))
- goto out_unlock_up;
ipcp = &msq->q_perm;
err = audit_ipc_obj(ipcp);
break;
}
case IPC_RMID:
- freeque(ns, msq);
+ freeque(ns, &msq->q_perm);
break;
}
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);
msg->m_type = mtype;
msg->m_ts = msgsz;
- msq = msg_lock(ns, msqid);
- err = -EINVAL;
- if (msq == NULL)
+ msq = msg_lock_check(ns, msqid);
+ if (IS_ERR(msq)) {
+ err = PTR_ERR(msq);
goto out_free;
-
- err= -EIDRM;
- if (msg_checkid(ns, msq, msqid))
- goto out_unlock_free;
+ }
for (;;) {
struct msg_sender s;
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;
mode = convert_mode(&msgtyp, msgflg);
ns = current->nsproxy->ipc_ns;
- msq = msg_lock(ns, msqid);
- if (msq == NULL)
- return -EINVAL;
-
- msg = ERR_PTR(-EIDRM);
- if (msg_checkid(ns, msq, msqid))
- goto out_unlock;
+ msq = msg_lock_check(ns, msqid);
+ if (IS_ERR(msq))
+ return PTR_ERR(msq);
for (;;) {
struct msg_receiver msr_d;
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.samba.org / sfrench / cifs-2.6.git / blobdiff