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-rw-r--r--ipc/msg.c188
1 files changed, 92 insertions, 96 deletions
diff --git a/ipc/msg.c b/ipc/msg.c
index 649853105a5d..c5d8e3749985 100644
--- a/ipc/msg.c
+++ b/ipc/msg.c
@@ -39,12 +39,10 @@
#include <linux/ipc_namespace.h>
#include <asm/current.h>
-#include <asm/uaccess.h>
+#include <linux/uaccess.h>
#include "util.h"
-/*
- * one msg_receiver structure for each sleeping receiver:
- */
+/* one msg_receiver structure for each sleeping receiver */
struct msg_receiver {
struct list_head r_list;
struct task_struct *r_tsk;
@@ -53,6 +51,12 @@ struct msg_receiver {
long r_msgtype;
long r_maxsize;
+ /*
+ * Mark r_msg volatile so that the compiler
+ * does not try to get smart and optimize
+ * it. We rely on this for the lockless
+ * receive algorithm.
+ */
struct msg_msg *volatile r_msg;
};
@@ -70,75 +74,6 @@ struct msg_sender {
#define msg_ids(ns) ((ns)->ids[IPC_MSG_IDS])
-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
-
-/*
- * Scale msgmni with the available lowmem size: the memory dedicated to msg
- * queues should occupy at most 1/MSG_MEM_SCALE of lowmem.
- * Also take into account the number of nsproxies created so far.
- * This should be done staying within the (MSGMNI , IPCMNI/nr_ipc_ns) range.
- */
-void recompute_msgmni(struct ipc_namespace *ns)
-{
- struct sysinfo i;
- unsigned long allowed;
- int nb_ns;
-
- si_meminfo(&i);
- allowed = (((i.totalram - i.totalhigh) / MSG_MEM_SCALE) * i.mem_unit)
- / MSGMNB;
- nb_ns = atomic_read(&nr_ipc_ns);
- allowed /= nb_ns;
-
- if (allowed < MSGMNI) {
- ns->msg_ctlmni = MSGMNI;
- return;
- }
-
- if (allowed > IPCMNI / nb_ns) {
- ns->msg_ctlmni = IPCMNI / nb_ns;
- return;
- }
-
- ns->msg_ctlmni = allowed;
-}
-
-void msg_init_ns(struct ipc_namespace *ns)
-{
- ns->msg_ctlmax = MSGMAX;
- ns->msg_ctlmnb = MSGMNB;
-
- recompute_msgmni(ns);
-
- atomic_set(&ns->msg_bytes, 0);
- atomic_set(&ns->msg_hdrs, 0);
- ipc_init_ids(&ns->ids[IPC_MSG_IDS]);
-}
-
-#ifdef CONFIG_IPC_NS
-void msg_exit_ns(struct ipc_namespace *ns)
-{
- free_ipcs(ns, &msg_ids(ns), freeque);
- idr_destroy(&ns->ids[IPC_MSG_IDS].ipcs_idr);
-}
-#endif
-
-void __init msg_init(void)
-{
- msg_init_ns(&init_ipc_ns);
-
- printk(KERN_INFO "msgmni has been set to %d\n",
- init_ipc_ns.msg_ctlmni);
-
- 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);
-}
-
static inline struct msg_queue *msq_obtain_object(struct ipc_namespace *ns, int id)
{
struct kern_ipc_perm *ipcp = ipc_obtain_object(&msg_ids(ns), id);
@@ -227,7 +162,7 @@ static int newque(struct ipc_namespace *ns, struct ipc_params *params)
static inline void ss_add(struct msg_queue *msq, struct msg_sender *mss)
{
mss->tsk = current;
- current->state = TASK_INTERRUPTIBLE;
+ __set_current_state(TASK_INTERRUPTIBLE);
list_add_tail(&mss->list, &msq->q_senders);
}
@@ -306,15 +241,14 @@ static inline int msg_security(struct kern_ipc_perm *ipcp, int msgflg)
SYSCALL_DEFINE2(msgget, key_t, key, int, msgflg)
{
struct ipc_namespace *ns;
- struct ipc_ops msg_ops;
+ static const struct ipc_ops msg_ops = {
+ .getnew = newque,
+ .associate = msg_security,
+ };
struct ipc_params msg_params;
ns = current->nsproxy->ipc_ns;
- msg_ops.getnew = newque;
- msg_ops.associate = msg_security;
- msg_ops.more_checks = NULL;
-
msg_params.key = key;
msg_params.flg = msgflg;
@@ -612,23 +546,22 @@ SYSCALL_DEFINE3(msgctl, int, msqid, int, cmd, struct msqid_ds __user *, buf)
static int testmsg(struct msg_msg *msg, long type, int mode)
{
- switch (mode)
- {
- case SEARCH_ANY:
- case SEARCH_NUMBER:
+ switch (mode) {
+ case SEARCH_ANY:
+ case SEARCH_NUMBER:
+ return 1;
+ case SEARCH_LESSEQUAL:
+ if (msg->m_type <= type)
return 1;
- case SEARCH_LESSEQUAL:
- if (msg->m_type <= type)
- return 1;
- break;
- case SEARCH_EQUAL:
- if (msg->m_type == type)
- return 1;
- break;
- case SEARCH_NOTEQUAL:
- if (msg->m_type != type)
- return 1;
- break;
+ break;
+ case SEARCH_EQUAL:
+ if (msg->m_type == type)
+ return 1;
+ break;
+ case SEARCH_NOTEQUAL:
+ if (msg->m_type != type)
+ return 1;
+ break;
}
return 0;
}
@@ -978,7 +911,7 @@ long do_msgrcv(int msqid, void __user *buf, size_t bufsz, long msgtyp, int msgfl
else
msr_d.r_maxsize = bufsz;
msr_d.r_msg = ERR_PTR(-EAGAIN);
- current->state = TASK_INTERRUPTIBLE;
+ __set_current_state(TASK_INTERRUPTIBLE);
ipc_unlock_object(&msq->q_perm);
rcu_read_unlock();
@@ -1056,6 +989,57 @@ SYSCALL_DEFINE5(msgrcv, int, msqid, struct msgbuf __user *, msgp, size_t, msgsz,
return do_msgrcv(msqid, msgp, msgsz, msgtyp, msgflg, do_msg_fill);
}
+/*
+ * Scale msgmni with the available lowmem size: the memory dedicated to msg
+ * queues should occupy at most 1/MSG_MEM_SCALE of lowmem.
+ * Also take into account the number of nsproxies created so far.
+ * This should be done staying within the (MSGMNI , IPCMNI/nr_ipc_ns) range.
+ */
+void recompute_msgmni(struct ipc_namespace *ns)
+{
+ struct sysinfo i;
+ unsigned long allowed;
+ int nb_ns;
+
+ si_meminfo(&i);
+ allowed = (((i.totalram - i.totalhigh) / MSG_MEM_SCALE) * i.mem_unit)
+ / MSGMNB;
+ nb_ns = atomic_read(&nr_ipc_ns);
+ allowed /= nb_ns;
+
+ if (allowed < MSGMNI) {
+ ns->msg_ctlmni = MSGMNI;
+ return;
+ }
+
+ if (allowed > IPCMNI / nb_ns) {
+ ns->msg_ctlmni = IPCMNI / nb_ns;
+ return;
+ }
+
+ ns->msg_ctlmni = allowed;
+}
+
+void msg_init_ns(struct ipc_namespace *ns)
+{
+ ns->msg_ctlmax = MSGMAX;
+ ns->msg_ctlmnb = MSGMNB;
+
+ recompute_msgmni(ns);
+
+ atomic_set(&ns->msg_bytes, 0);
+ atomic_set(&ns->msg_hdrs, 0);
+ ipc_init_ids(&ns->ids[IPC_MSG_IDS]);
+}
+
+#ifdef CONFIG_IPC_NS
+void msg_exit_ns(struct ipc_namespace *ns)
+{
+ free_ipcs(ns, &msg_ids(ns), freeque);
+ idr_destroy(&ns->ids[IPC_MSG_IDS].ipcs_idr);
+}
+#endif
+
#ifdef CONFIG_PROC_FS
static int sysvipc_msg_proc_show(struct seq_file *s, void *it)
{
@@ -1080,3 +1064,15 @@ static int sysvipc_msg_proc_show(struct seq_file *s, void *it)
msq->q_ctime);
}
#endif
+
+void __init msg_init(void)
+{
+ msg_init_ns(&init_ipc_ns);
+
+ printk(KERN_INFO "msgmni has been set to %d\n",
+ init_ipc_ns.msg_ctlmni);
+
+ 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);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-19 09:44:07 +0000