ipc: simplify message copying
Remove the redundant and confusing fill_copy(). Also add copy_msg()
check for error. In this case exit from the function have to be done
instead of break, because further code interprets any error as EAGAIN.
Also define copy_msg() for the case when CONFIG_CHECKPOINT_RESTORE is
disabled.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/ipc/msg.c b/ipc/msg.c
index 038a7d7..8493e1d 100644
--- a/ipc/msg.c
+++ b/ipc/msg.c
@@ -770,16 +770,6 @@
}
#ifdef CONFIG_CHECKPOINT_RESTORE
-static inline struct msg_msg *fill_copy(unsigned long copy_nr,
- unsigned long msg_nr,
- struct msg_msg *msg,
- struct msg_msg *copy)
-{
- if (copy_nr == msg_nr)
- return copy_msg(msg, copy);
- return NULL;
-}
-
static inline struct msg_msg *prepare_copy(void __user *buf, size_t bufsz,
int msgflg, long *msgtyp,
unsigned long *copy_number)
@@ -803,8 +793,6 @@
free_msg(copy);
}
#else
-#define fill_copy(copy_nr, msg_nr, msg, copy) NULL
-
static inline struct msg_msg *prepare_copy(void __user *buf, size_t bufsz,
int msgflg, long *msgtyp,
unsigned long *copy_number)
@@ -868,11 +856,16 @@
walk_msg->m_type != 1) {
msgtyp = walk_msg->m_type - 1;
} else if (msgflg & MSG_COPY) {
- msg = fill_copy(copy_number,
- msg_counter,
- walk_msg, copy);
- if (msg)
+ if (copy_number == msg_counter) {
+ /*
+ * Found requested message.
+ * Copy it.
+ */
+ msg = copy_msg(msg, copy);
+ if (IS_ERR(msg))
+ goto out_unlock;
break;
+ }
} else
break;
msg_counter++;
diff --git a/ipc/msgutil.c b/ipc/msgutil.c
index 7eecdad..ebfcbfa 100644
--- a/ipc/msgutil.c
+++ b/ipc/msgutil.c
@@ -140,6 +140,11 @@
return dst;
}
+#else
+struct msg_msg *copy_msg(struct msg_msg *src, struct msg_msg *dst)
+{
+ return ERR_PTR(-ENOSYS);
+}
#endif
int store_msg(void __user *dest, struct msg_msg *msg, int len)
{