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authorNadia Derbey <Nadia.Derbey@bull.net>2007-10-18 23:40:48 -0700
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-10-19 11:53:44 -0700
commit7ca7e564e049d8b350ec9d958ff25eaa24226352 (patch)
treee3c1397dc898dbd7c685c6a052425e7346eb79d1 /ipc/msg.c
parentd2b20b11547cefc89d6c81937e81afaf3c62808b (diff)
downloadlinux-7ca7e564e049d8b350ec9d958ff25eaa24226352.tar.gz
ipc: store ipcs into IDRs
This patch introduces ipcs storage into IDRs. The main changes are: . This ipc_ids structure is changed: the entries array is changed into a root idr structure. . The grow_ary() routine is removed: it is not needed anymore when adding an ipc structure, since we are now using the IDR facility. . The ipc_rmid() routine interface is changed: . there is no need for this routine to return the pointer passed in as argument: it is now declared as a void . since the id is now part of the kern_ipc_perm structure, no need to have it as an argument to the routine Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'ipc/msg.c')
-rw-r--r--ipc/msg.c115
1 files changed, 70 insertions, 45 deletions
diff --git a/ipc/msg.c b/ipc/msg.c
index 319468609b7..08591a0278c 100644
--- a/ipc/msg.c
+++ b/ipc/msg.c
@@ -75,13 +75,12 @@ static struct ipc_ids init_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_rmid(ns, id) ((struct msg_queue*)ipc_rmid(&msg_ids(ns), id))
#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)
-static void freeque (struct ipc_namespace *ns, struct msg_queue *msq, int id);
+static void freeque(struct ipc_namespace *, struct msg_queue *);
static int newque (struct ipc_namespace *ns, key_t key, int msgflg);
#ifdef CONFIG_PROC_FS
static int sysvipc_msg_proc_show(struct seq_file *s, void *it);
@@ -93,7 +92,7 @@ static void __msg_init_ns(struct ipc_namespace *ns, struct ipc_ids *ids)
ns->msg_ctlmax = MSGMAX;
ns->msg_ctlmnb = MSGMNB;
ns->msg_ctlmni = MSGMNI;
- ipc_init_ids(ids, ns->msg_ctlmni);
+ ipc_init_ids(ids);
}
int msg_init_ns(struct ipc_namespace *ns)
@@ -110,20 +109,24 @@ int msg_init_ns(struct ipc_namespace *ns)
void msg_exit_ns(struct ipc_namespace *ns)
{
- int i;
struct msg_queue *msq;
+ int next_id;
+ int total, in_use;
mutex_lock(&msg_ids(ns).mutex);
- for (i = 0; i <= msg_ids(ns).max_id; i++) {
- msq = msg_lock(ns, i);
+
+ 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)
continue;
-
- freeque(ns, msq, i);
+ ipc_lock_by_ptr(&msq->q_perm);
+ freeque(ns, msq);
+ total++;
}
mutex_unlock(&msg_ids(ns).mutex);
- ipc_fini_ids(ns->ids[IPC_MSG_IDS]);
kfree(ns->ids[IPC_MSG_IDS]);
ns->ids[IPC_MSG_IDS] = NULL;
}
@@ -136,6 +139,11 @@ void __init msg_init(void)
IPC_MSG_IDS, sysvipc_msg_proc_show);
}
+static inline void msg_rmid(struct ipc_namespace *ns, struct msg_queue *s)
+{
+ ipc_rmid(&msg_ids(ns), &s->q_perm);
+}
+
static int newque (struct ipc_namespace *ns, key_t key, int msgflg)
{
struct msg_queue *msq;
@@ -155,6 +163,9 @@ static int newque (struct ipc_namespace *ns, key_t key, int msgflg)
return retval;
}
+ /*
+ * ipc_addid() locks msq
+ */
id = ipc_addid(&msg_ids(ns), &msq->q_perm, ns->msg_ctlmni);
if (id == -1) {
security_msg_queue_free(msq);
@@ -162,7 +173,7 @@ static int newque (struct ipc_namespace *ns, key_t key, int msgflg)
return -ENOSPC;
}
- msq->q_id = msg_buildid(ns, id, msq->q_perm.seq);
+ msq->q_perm.id = msg_buildid(ns, id, msq->q_perm.seq);
msq->q_stime = msq->q_rtime = 0;
msq->q_ctime = get_seconds();
msq->q_cbytes = msq->q_qnum = 0;
@@ -171,9 +182,10 @@ static int newque (struct ipc_namespace *ns, key_t key, int msgflg)
INIT_LIST_HEAD(&msq->q_messages);
INIT_LIST_HEAD(&msq->q_receivers);
INIT_LIST_HEAD(&msq->q_senders);
+
msg_unlock(msq);
- return msq->q_id;
+ return msq->q_perm.id;
}
static inline void ss_add(struct msg_queue *msq, struct msg_sender *mss)
@@ -225,18 +237,18 @@ static void expunge_all(struct msg_queue *msq, int res)
/*
* freeque() wakes up waiters on the sender and receiver waiting queue,
* removes the message queue from message queue ID
- * array, and cleans up all the messages associated with this queue.
+ * IDR, and cleans up all the messages associated with this queue.
*
- * msg_ids.mutex and the spinlock for this message queue is hold
+ * msg_ids.mutex and the spinlock for this message queue are held
* before freeque() is called. msg_ids.mutex remains locked on exit.
*/
-static void freeque(struct ipc_namespace *ns, struct msg_queue *msq, int id)
+static void freeque(struct ipc_namespace *ns, struct msg_queue *msq)
{
struct list_head *tmp;
expunge_all(msq, -EIDRM);
ss_wakeup(&msq->q_senders, 1);
- msq = msg_rmid(ns, id);
+ msg_rmid(ns, msq);
msg_unlock(msq);
tmp = msq->q_messages.next;
@@ -255,36 +267,51 @@ static void freeque(struct ipc_namespace *ns, struct msg_queue *msq, int id)
asmlinkage long sys_msgget(key_t key, int msgflg)
{
struct msg_queue *msq;
- int id, ret = -EPERM;
+ int ret;
struct ipc_namespace *ns;
ns = current->nsproxy->ipc_ns;
-
- mutex_lock(&msg_ids(ns).mutex);
- if (key == IPC_PRIVATE)
- ret = newque(ns, key, msgflg);
- else if ((id = ipc_findkey(&msg_ids(ns), key)) == -1) { /* key not used */
- if (!(msgflg & IPC_CREAT))
- ret = -ENOENT;
- else
+
+ ret = idr_pre_get(&msg_ids(ns).ipcs_idr, GFP_KERNEL);
+
+ if (key == IPC_PRIVATE) {
+ if (!ret)
+ ret = -ENOMEM;
+ else {
+ mutex_lock(&msg_ids(ns).mutex);
ret = newque(ns, key, msgflg);
- } else if (msgflg & IPC_CREAT && msgflg & IPC_EXCL) {
- ret = -EEXIST;
+ mutex_unlock(&msg_ids(ns).mutex);
+ }
} else {
- msq = msg_lock(ns, id);
- BUG_ON(msq == NULL);
- if (ipcperms(&msq->q_perm, msgflg))
- ret = -EACCES;
- else {
- int qid = msg_buildid(ns, id, msq->q_perm.seq);
-
- ret = security_msg_queue_associate(msq, msgflg);
- if (!ret)
- ret = qid;
+ mutex_lock(&msg_ids(ns).mutex);
+ msq = (struct msg_queue *) ipc_findkey(&msg_ids(ns), key);
+ if (msq == NULL) {
+ /* key not used */
+ if (!(msgflg & IPC_CREAT))
+ ret = -ENOENT;
+ else if (!ret)
+ ret = -ENOMEM;
+ else
+ ret = newque(ns, key, msgflg);
+ } else {
+ /* msq has been locked by ipc_findkey() */
+
+ if (msgflg & IPC_CREAT && msgflg & IPC_EXCL)
+ ret = -EEXIST;
+ else {
+ if (ipcperms(&msq->q_perm, msgflg))
+ ret = -EACCES;
+ else {
+ ret = security_msg_queue_associate(
+ msq, msgflg);
+ if (!ret)
+ ret = msq->q_perm.id;
+ }
+ }
+ msg_unlock(msq);
}
- msg_unlock(msq);
+ mutex_unlock(&msg_ids(ns).mutex);
}
- mutex_unlock(&msg_ids(ns).mutex);
return ret;
}
@@ -430,13 +457,13 @@ asmlinkage long sys_msgctl(int msqid, int cmd, struct msqid_ds __user *buf)
msginfo.msgpool = MSGPOOL;
msginfo.msgtql = MSGTQL;
}
- max_id = msg_ids(ns).max_id;
+ max_id = ipc_get_maxid(&msg_ids(ns));
mutex_unlock(&msg_ids(ns).mutex);
if (copy_to_user(buf, &msginfo, sizeof(struct msginfo)))
return -EFAULT;
return (max_id < 0) ? 0 : max_id;
}
- case MSG_STAT:
+ case MSG_STAT: /* msqid is an index rather than a msg queue id */
case IPC_STAT:
{
struct msqid64_ds tbuf;
@@ -444,8 +471,6 @@ asmlinkage long sys_msgctl(int msqid, int cmd, struct msqid_ds __user *buf)
if (!buf)
return -EFAULT;
- if (cmd == MSG_STAT && msqid >= msg_ids(ns).entries->size)
- return -EINVAL;
memset(&tbuf, 0, sizeof(tbuf));
@@ -454,7 +479,7 @@ asmlinkage long sys_msgctl(int msqid, int cmd, struct msqid_ds __user *buf)
return -EINVAL;
if (cmd == MSG_STAT) {
- success_return = msg_buildid(ns, msqid, msq->q_perm.seq);
+ success_return = msq->q_perm.id;
} else {
err = -EIDRM;
if (msg_checkid(ns, msq, msqid))
@@ -552,7 +577,7 @@ asmlinkage long sys_msgctl(int msqid, int cmd, struct msqid_ds __user *buf)
break;
}
case IPC_RMID:
- freeque(ns, msq, msqid);
+ freeque(ns, msq);
break;
}
err = 0;
@@ -926,7 +951,7 @@ static int sysvipc_msg_proc_show(struct seq_file *s, void *it)
return seq_printf(s,
"%10d %10d %4o %10lu %10lu %5u %5u %5u %5u %5u %5u %10lu %10lu %10lu\n",
msq->q_perm.key,
- msq->q_id,
+ msq->q_perm.id,
msq->q_perm.mode,
msq->q_cbytes,
msq->q_qnum,