Currently we allocate 64k space on the user stack and use it the msgbuf for sys_{msgrcv,msgsnd} for compat and the results are later copied in user [ by copy_in_user]. This patch introduces helper routines for sys_{msgrcv,msgsnd} as below: do_msgsnd() : Accepts the mtype and user space ptr to the buffer along with the msqid and msgflg. do_msgrcv() : Accepts a kernel space ptr to mtype and a userspace ptr to the buffer. The mtype has to be copied back the user space msgbuf by the caller. These changes avoid the need to allocate the msgsize on the userspace ( thus removing the size limt ) and the overhead of an extra copy_in_user(). Signed-off-by: Suzuki K P <suzuki@in.ibm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org> |
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.. | ||
Makefile | ||
compat.c | ||
compat_mq.c | ||
mqueue.c | ||
msg.c | ||
msgutil.c | ||
sem.c | ||
shm.c | ||
util.c | ||
util.h |