diff --git a/Documentation/sysctl/fs.txt b/Documentation/sysctl/fs.txt index 88fd7f5c8dcd..13d6166d7a27 100644 --- a/Documentation/sysctl/fs.txt +++ b/Documentation/sysctl/fs.txt @@ -225,6 +225,13 @@ a queue must be less or equal then msg_max. maximum message size value (it is every message queue's attribute set during its creation). +/proc/sys/fs/mqueue/msg_default is a read/write file for setting/getting the +default number of messages in a queue value if attr parameter of mq_open(2) is +NULL. If it exceed msg_max, the default value is initialized msg_max. + +/proc/sys/fs/mqueue/msgsize_default is a read/write file for setting/getting +the default message size value if attr parameter of mq_open(2) is NULL. If it +exceed msgsize_max, the default value is initialized msgsize_max. 4. /proc/sys/fs/epoll - Configuration options for the epoll interface -------------------------------------------------------- diff --git a/include/linux/ipc_namespace.h b/include/linux/ipc_namespace.h index 2488535a32a3..5499c92a9153 100644 --- a/include/linux/ipc_namespace.h +++ b/include/linux/ipc_namespace.h @@ -62,6 +62,8 @@ struct ipc_namespace { unsigned int mq_queues_max; /* initialized to DFLT_QUEUESMAX */ unsigned int mq_msg_max; /* initialized to DFLT_MSGMAX */ unsigned int mq_msgsize_max; /* initialized to DFLT_MSGSIZEMAX */ + unsigned int mq_msg_default; + unsigned int mq_msgsize_default; /* user_ns which owns the ipc ns */ struct user_namespace *user_ns; diff --git a/ipc/mq_sysctl.c b/ipc/mq_sysctl.c index e22336a09b4a..383d638340b8 100644 --- a/ipc/mq_sysctl.c +++ b/ipc/mq_sysctl.c @@ -73,6 +73,24 @@ static ctl_table mq_sysctls[] = { .extra1 = &msg_maxsize_limit_min, .extra2 = &msg_maxsize_limit_max, }, + { + .procname = "msg_default", + .data = &init_ipc_ns.mq_msg_default, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_mq_dointvec_minmax, + .extra1 = &msg_max_limit_min, + .extra2 = &msg_max_limit_max, + }, + { + .procname = "msgsize_default", + .data = &init_ipc_ns.mq_msgsize_default, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_mq_dointvec_minmax, + .extra1 = &msg_maxsize_limit_min, + .extra2 = &msg_maxsize_limit_max, + }, {} }; diff --git a/ipc/mqueue.c b/ipc/mqueue.c index 6828e2c93cef..609d53f7a915 100644 --- a/ipc/mqueue.c +++ b/ipc/mqueue.c @@ -145,9 +145,10 @@ static struct inode *mqueue_get_inode(struct super_block *sb, info->qsize = 0; info->user = NULL; /* set when all is ok */ memset(&info->attr, 0, sizeof(info->attr)); - info->attr.mq_maxmsg = min(ipc_ns->mq_msg_max, DFLT_MSG); - info->attr.mq_msgsize = - min(ipc_ns->mq_msgsize_max, DFLT_MSGSIZE); + info->attr.mq_maxmsg = min(ipc_ns->mq_msg_max, + ipc_ns->mq_msg_default); + info->attr.mq_msgsize = min(ipc_ns->mq_msgsize_max, + ipc_ns->mq_msgsize_default); if (attr) { info->attr.mq_maxmsg = attr->mq_maxmsg; info->attr.mq_msgsize = attr->mq_msgsize; @@ -1261,6 +1262,8 @@ int mq_init_ns(struct ipc_namespace *ns) ns->mq_queues_max = DFLT_QUEUESMAX; ns->mq_msg_max = DFLT_MSGMAX; ns->mq_msgsize_max = DFLT_MSGSIZEMAX; + ns->mq_msg_default = DFLT_MSG; + ns->mq_msgsize_default = DFLT_MSGSIZE; ns->mq_mnt = kern_mount_data(&mqueue_fs_type, ns); if (IS_ERR(ns->mq_mnt)) {