namespaces: mqueue ns: move mqueue_mnt into struct ipc_namespace
Move mqueue vfsmount plus a few tunables into the ipc_namespace struct.
The CONFIG_IPC_NS boolean and the ipc_namespace struct will serve both the
posix message queue namespaces and the SYSV ipc namespaces.
The sysctl code will be fixed separately in patch 3. After just this
patch, making a change to posix mqueue tunables always changes the values
in the initial ipc namespace.
Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/ipc/mqueue.c b/ipc/mqueue.c
index 9167853..a3673a0 100644
--- a/ipc/mqueue.c
+++ b/ipc/mqueue.c
@@ -31,6 +31,7 @@
#include <linux/mutex.h>
#include <linux/nsproxy.h>
#include <linux/pid.h>
+#include <linux/ipc_namespace.h>
#include <net/sock.h>
#include "util.h"
@@ -46,12 +47,6 @@
#define STATE_PENDING 1
#define STATE_READY 2
-/* default values */
-#define DFLT_QUEUESMAX 256 /* max number of message queues */
-#define DFLT_MSGMAX 10 /* max number of messages in each queue */
-#define HARD_MSGMAX (131072/sizeof(void*))
-#define DFLT_MSGSIZEMAX 8192 /* max message size */
-
/*
* Define the ranges various user-specified maximum values can
* be set to.
@@ -95,12 +90,6 @@
static spinlock_t mq_lock;
static struct kmem_cache *mqueue_inode_cachep;
-static struct vfsmount *mqueue_mnt;
-
-static unsigned int queues_count;
-static unsigned int queues_max = DFLT_QUEUESMAX;
-static unsigned int msg_max = DFLT_MSGMAX;
-static unsigned int msgsize_max = DFLT_MSGSIZEMAX;
static struct ctl_table_header * mq_sysctl_table;
@@ -109,11 +98,27 @@
return container_of(inode, struct mqueue_inode_info, vfs_inode);
}
+void mq_init_ns(struct ipc_namespace *ns)
+{
+ ns->mq_queues_count = 0;
+ ns->mq_queues_max = DFLT_QUEUESMAX;
+ ns->mq_msg_max = DFLT_MSGMAX;
+ ns->mq_msgsize_max = DFLT_MSGSIZEMAX;
+ ns->mq_mnt = mntget(init_ipc_ns.mq_mnt);
+}
+
+void mq_exit_ns(struct ipc_namespace *ns)
+{
+ /* will need to clear out ns->mq_mnt->mnt_sb->s_fs_info here */
+ mntput(ns->mq_mnt);
+}
+
static struct inode *mqueue_get_inode(struct super_block *sb, int mode,
struct mq_attr *attr)
{
struct user_struct *u = current_user();
struct inode *inode;
+ struct ipc_namespace *ipc_ns = &init_ipc_ns;
inode = new_inode(sb);
if (inode) {
@@ -141,8 +146,8 @@
info->qsize = 0;
info->user = NULL; /* set when all is ok */
memset(&info->attr, 0, sizeof(info->attr));
- info->attr.mq_maxmsg = msg_max;
- info->attr.mq_msgsize = msgsize_max;
+ info->attr.mq_maxmsg = ipc_ns->mq_msg_max;
+ info->attr.mq_msgsize = ipc_ns->mq_msgsize_max;
if (attr) {
info->attr.mq_maxmsg = attr->mq_maxmsg;
info->attr.mq_msgsize = attr->mq_msgsize;
@@ -242,6 +247,7 @@
struct user_struct *user;
unsigned long mq_bytes;
int i;
+ struct ipc_namespace *ipc_ns = &init_ipc_ns;
if (S_ISDIR(inode->i_mode)) {
clear_inode(inode);
@@ -262,7 +268,7 @@
if (user) {
spin_lock(&mq_lock);
user->mq_bytes -= mq_bytes;
- queues_count--;
+ ipc_ns->mq_queues_count--;
spin_unlock(&mq_lock);
free_uid(user);
}
@@ -274,21 +280,23 @@
struct inode *inode;
struct mq_attr *attr = dentry->d_fsdata;
int error;
+ struct ipc_namespace *ipc_ns = &init_ipc_ns;
spin_lock(&mq_lock);
- if (queues_count >= queues_max && !capable(CAP_SYS_RESOURCE)) {
+ if (ipc_ns->mq_queues_count >= ipc_ns->mq_queues_max &&
+ !capable(CAP_SYS_RESOURCE)) {
error = -ENOSPC;
- goto out_lock;
+ goto out_unlock;
}
- queues_count++;
+ ipc_ns->mq_queues_count++;
spin_unlock(&mq_lock);
inode = mqueue_get_inode(dir->i_sb, mode, attr);
if (!inode) {
error = -ENOMEM;
spin_lock(&mq_lock);
- queues_count--;
- goto out_lock;
+ ipc_ns->mq_queues_count--;
+ goto out_unlock;
}
dir->i_size += DIRENT_SIZE;
@@ -297,7 +305,7 @@
d_instantiate(dentry, inode);
dget(dentry);
return 0;
-out_lock:
+out_unlock:
spin_unlock(&mq_lock);
return error;
}
@@ -562,7 +570,7 @@
info->notify_owner = NULL;
}
-static int mq_attr_ok(struct mq_attr *attr)
+static int mq_attr_ok(struct ipc_namespace *ipc_ns, struct mq_attr *attr)
{
if (attr->mq_maxmsg <= 0 || attr->mq_msgsize <= 0)
return 0;
@@ -570,8 +578,8 @@
if (attr->mq_maxmsg > HARD_MSGMAX)
return 0;
} else {
- if (attr->mq_maxmsg > msg_max ||
- attr->mq_msgsize > msgsize_max)
+ if (attr->mq_maxmsg > ipc_ns->mq_msg_max ||
+ attr->mq_msgsize > ipc_ns->mq_msgsize_max)
return 0;
}
/* check for overflow */
@@ -587,8 +595,9 @@
/*
* Invoked when creating a new queue via sys_mq_open
*/
-static struct file *do_create(struct dentry *dir, struct dentry *dentry,
- int oflag, mode_t mode, struct mq_attr *attr)
+static struct file *do_create(struct ipc_namespace *ipc_ns, struct dentry *dir,
+ struct dentry *dentry, int oflag, mode_t mode,
+ struct mq_attr *attr)
{
const struct cred *cred = current_cred();
struct file *result;
@@ -596,14 +605,14 @@
if (attr) {
ret = -EINVAL;
- if (!mq_attr_ok(attr))
+ if (!mq_attr_ok(ipc_ns, attr))
goto out;
/* store for use during create */
dentry->d_fsdata = attr;
}
mode &= ~current_umask();
- ret = mnt_want_write(mqueue_mnt);
+ ret = mnt_want_write(ipc_ns->mq_mnt);
if (ret)
goto out;
ret = vfs_create(dir->d_inode, dentry, mode, NULL);
@@ -611,24 +620,25 @@
if (ret)
goto out_drop_write;
- result = dentry_open(dentry, mqueue_mnt, oflag, cred);
+ result = dentry_open(dentry, ipc_ns->mq_mnt, oflag, cred);
/*
* dentry_open() took a persistent mnt_want_write(),
* so we can now drop this one.
*/
- mnt_drop_write(mqueue_mnt);
+ mnt_drop_write(ipc_ns->mq_mnt);
return result;
out_drop_write:
- mnt_drop_write(mqueue_mnt);
+ mnt_drop_write(ipc_ns->mq_mnt);
out:
dput(dentry);
- mntput(mqueue_mnt);
+ mntput(ipc_ns->mq_mnt);
return ERR_PTR(ret);
}
/* Opens existing queue */
-static struct file *do_open(struct dentry *dentry, int oflag)
+static struct file *do_open(struct ipc_namespace *ipc_ns,
+ struct dentry *dentry, int oflag)
{
const struct cred *cred = current_cred();
@@ -637,17 +647,17 @@
if ((oflag & O_ACCMODE) == (O_RDWR | O_WRONLY)) {
dput(dentry);
- mntput(mqueue_mnt);
+ mntput(ipc_ns->mq_mnt);
return ERR_PTR(-EINVAL);
}
if (inode_permission(dentry->d_inode, oflag2acc[oflag & O_ACCMODE])) {
dput(dentry);
- mntput(mqueue_mnt);
+ mntput(ipc_ns->mq_mnt);
return ERR_PTR(-EACCES);
}
- return dentry_open(dentry, mqueue_mnt, oflag, cred);
+ return dentry_open(dentry, ipc_ns->mq_mnt, oflag, cred);
}
SYSCALL_DEFINE4(mq_open, const char __user *, u_name, int, oflag, mode_t, mode,
@@ -658,6 +668,7 @@
char *name;
struct mq_attr attr;
int fd, error;
+ struct ipc_namespace *ipc_ns = &init_ipc_ns;
if (u_attr && copy_from_user(&attr, u_attr, sizeof(struct mq_attr)))
return -EFAULT;
@@ -671,13 +682,13 @@
if (fd < 0)
goto out_putname;
- mutex_lock(&mqueue_mnt->mnt_root->d_inode->i_mutex);
- dentry = lookup_one_len(name, mqueue_mnt->mnt_root, strlen(name));
+ mutex_lock(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex);
+ dentry = lookup_one_len(name, ipc_ns->mq_mnt->mnt_root, strlen(name));
if (IS_ERR(dentry)) {
error = PTR_ERR(dentry);
goto out_err;
}
- mntget(mqueue_mnt);
+ mntget(ipc_ns->mq_mnt);
if (oflag & O_CREAT) {
if (dentry->d_inode) { /* entry already exists */
@@ -685,10 +696,10 @@
error = -EEXIST;
if (oflag & O_EXCL)
goto out;
- filp = do_open(dentry, oflag);
+ filp = do_open(ipc_ns, dentry, oflag);
} else {
- filp = do_create(mqueue_mnt->mnt_root, dentry,
- oflag, mode,
+ filp = do_create(ipc_ns, ipc_ns->mq_mnt->mnt_root,
+ dentry, oflag, mode,
u_attr ? &attr : NULL);
}
} else {
@@ -696,7 +707,7 @@
if (!dentry->d_inode)
goto out;
audit_inode(name, dentry);
- filp = do_open(dentry, oflag);
+ filp = do_open(ipc_ns, dentry, oflag);
}
if (IS_ERR(filp)) {
@@ -709,13 +720,13 @@
out:
dput(dentry);
- mntput(mqueue_mnt);
+ mntput(ipc_ns->mq_mnt);
out_putfd:
put_unused_fd(fd);
out_err:
fd = error;
out_upsem:
- mutex_unlock(&mqueue_mnt->mnt_root->d_inode->i_mutex);
+ mutex_unlock(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex);
out_putname:
putname(name);
return fd;
@@ -727,14 +738,15 @@
char *name;
struct dentry *dentry;
struct inode *inode = NULL;
+ struct ipc_namespace *ipc_ns = &init_ipc_ns;
name = getname(u_name);
if (IS_ERR(name))
return PTR_ERR(name);
- mutex_lock_nested(&mqueue_mnt->mnt_root->d_inode->i_mutex,
+ mutex_lock_nested(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex,
I_MUTEX_PARENT);
- dentry = lookup_one_len(name, mqueue_mnt->mnt_root, strlen(name));
+ dentry = lookup_one_len(name, ipc_ns->mq_mnt->mnt_root, strlen(name));
if (IS_ERR(dentry)) {
err = PTR_ERR(dentry);
goto out_unlock;
@@ -748,16 +760,16 @@
inode = dentry->d_inode;
if (inode)
atomic_inc(&inode->i_count);
- err = mnt_want_write(mqueue_mnt);
+ err = mnt_want_write(ipc_ns->mq_mnt);
if (err)
goto out_err;
err = vfs_unlink(dentry->d_parent->d_inode, dentry);
- mnt_drop_write(mqueue_mnt);
+ mnt_drop_write(ipc_ns->mq_mnt);
out_err:
dput(dentry);
out_unlock:
- mutex_unlock(&mqueue_mnt->mnt_root->d_inode->i_mutex);
+ mutex_unlock(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex);
putname(name);
if (inode)
iput(inode);
@@ -1214,14 +1226,14 @@
static ctl_table mq_sysctls[] = {
{
.procname = "queues_max",
- .data = &queues_max,
+ .data = &init_ipc_ns.mq_queues_max,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.procname = "msg_max",
- .data = &msg_max,
+ .data = &init_ipc_ns.mq_msg_max,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
@@ -1230,7 +1242,7 @@
},
{
.procname = "msgsize_max",
- .data = &msgsize_max,
+ .data = &init_ipc_ns.mq_msgsize_max,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
@@ -1276,13 +1288,13 @@
if (error)
goto out_sysctl;
- if (IS_ERR(mqueue_mnt = kern_mount(&mqueue_fs_type))) {
- error = PTR_ERR(mqueue_mnt);
+ init_ipc_ns.mq_mnt = kern_mount(&mqueue_fs_type);
+ if (IS_ERR(init_ipc_ns.mq_mnt)) {
+ error = PTR_ERR(init_ipc_ns.mq_mnt);
goto out_filesystem;
}
/* internal initialization - not common for vfs */
- queues_count = 0;
spin_lock_init(&mq_lock);
return 0;