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>
This commit is contained in:
Stanislav Kinsbursky 2013-01-04 15:35:01 -08:00 committed by Linus Torvalds
parent b30efe2775
commit 51eeacaa07
2 changed files with 14 additions and 16 deletions

View File

@ -770,16 +770,6 @@ static long do_msg_fill(void __user *dest, struct msg_msg *msg, size_t bufsz)
}
#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 @@ static inline void free_copy(struct msg_msg *copy)
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 @@ long do_msgrcv(int msqid, void __user *buf, size_t bufsz, long msgtyp,
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++;

View File

@ -140,6 +140,11 @@ struct msg_msg *copy_msg(struct msg_msg *src, struct msg_msg *dst)
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)
{