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>
This commit is contained in:
Serge E. Hallyn 2009-04-06 19:01:08 -07:00 committed by Linus Torvalds
parent 909e6d9479
commit 614b84cf4e
7 changed files with 145 additions and 71 deletions

View File

@ -44,24 +44,55 @@ struct ipc_namespace {
int shm_tot;
struct notifier_block ipcns_nb;
/* The kern_mount of the mqueuefs sb. We take a ref on it */
struct vfsmount *mq_mnt;
/* # queues in this ns, protected by mq_lock */
unsigned int mq_queues_count;
/* next fields are set through sysctl */
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 */
};
extern struct ipc_namespace init_ipc_ns;
extern atomic_t nr_ipc_ns;
#ifdef CONFIG_SYSVIPC
#if defined(CONFIG_POSIX_MQUEUE) || defined(CONFIG_SYSVIPC)
#define INIT_IPC_NS(ns) .ns = &init_ipc_ns,
#else
#define INIT_IPC_NS(ns)
#endif
#ifdef CONFIG_SYSVIPC
extern int register_ipcns_notifier(struct ipc_namespace *);
extern int cond_register_ipcns_notifier(struct ipc_namespace *);
extern void unregister_ipcns_notifier(struct ipc_namespace *);
extern int ipcns_notify(unsigned long);
#else /* CONFIG_SYSVIPC */
#define INIT_IPC_NS(ns)
static inline int register_ipcns_notifier(struct ipc_namespace *ns)
{ return 0; }
static inline int cond_register_ipcns_notifier(struct ipc_namespace *ns)
{ return 0; }
static inline void unregister_ipcns_notifier(struct ipc_namespace *ns) { }
static inline int ipcns_notify(unsigned long l) { return 0; }
#endif /* CONFIG_SYSVIPC */
#if defined(CONFIG_SYSVIPC) && defined(CONFIG_IPC_NS)
#ifdef CONFIG_POSIX_MQUEUE
extern void mq_init_ns(struct ipc_namespace *ns);
/* 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 */
#else
#define mq_init_ns(ns) ((void) 0)
#endif
#if defined(CONFIG_IPC_NS)
extern void free_ipc_ns(struct kref *kref);
extern struct ipc_namespace *copy_ipcs(unsigned long flags,
struct ipc_namespace *ns);

View File

@ -670,10 +670,10 @@ config UTS_NS
config IPC_NS
bool "IPC namespace"
depends on NAMESPACES && SYSVIPC
depends on NAMESPACES && (SYSVIPC || POSIX_MQUEUE)
help
In this namespace tasks work with IPC ids which correspond to
different IPC objects in different namespaces
different IPC objects in different namespaces.
config USER_NS
bool "User namespace (EXPERIMENTAL)"

View File

@ -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 void remove_notification(struct mqueue_inode_info *info);
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 @@ static inline struct mqueue_inode_info *MQUEUE_I(struct inode *inode)
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 @@ static struct inode *mqueue_get_inode(struct super_block *sb, int mode,
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 @@ static void mqueue_delete_inode(struct inode *inode)
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 @@ static void mqueue_delete_inode(struct inode *inode)
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 @@ static int mqueue_create(struct inode *dir, struct dentry *dentry,
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 @@ static int mqueue_create(struct inode *dir, struct dentry *dentry,
d_instantiate(dentry, inode);
dget(dentry);
return 0;
out_lock:
out_unlock:
spin_unlock(&mq_lock);
return error;
}
@ -562,7 +570,7 @@ static void remove_notification(struct mqueue_inode_info *info)
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 @@ static int mq_attr_ok(struct mq_attr *attr)
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 @@ static int mq_attr_ok(struct mq_attr *attr)
/*
* 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 @@ static struct file *do_create(struct dentry *dir, struct dentry *dentry,
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 @@ static struct file *do_create(struct dentry *dir, struct dentry *dentry,
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 @@ static struct file *do_open(struct dentry *dentry, int oflag)
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 @@ SYSCALL_DEFINE4(mq_open, const char __user *, u_name, int, oflag, mode_t, mode,
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 @@ SYSCALL_DEFINE4(mq_open, const char __user *, u_name, int, oflag, mode_t, mode,
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 @@ SYSCALL_DEFINE4(mq_open, const char __user *, u_name, int, oflag, mode_t, mode,
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 @@ SYSCALL_DEFINE4(mq_open, const char __user *, u_name, int, oflag, mode_t, mode,
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 @@ SYSCALL_DEFINE4(mq_open, const char __user *, u_name, int, oflag, mode_t, mode,
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 @@ SYSCALL_DEFINE1(mq_unlink, const char __user *, u_name)
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 @@ SYSCALL_DEFINE1(mq_unlink, const char __user *, u_name)
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 int msg_maxsize_limit_max = MAX_MSGSIZEMAX;
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 @@ static ctl_table mq_sysctls[] = {
},
{
.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 @@ static int __init init_mqueue_fs(void)
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;

View File

@ -13,10 +13,32 @@
#include <linux/security.h>
#include <linux/slab.h>
#include <linux/ipc.h>
#include <linux/ipc_namespace.h>
#include <asm/uaccess.h>
#include "util.h"
/*
* The next 2 defines are here bc this is the only file
* compiled when either CONFIG_SYSVIPC and CONFIG_POSIX_MQUEUE
* and not CONFIG_IPC_NS.
*/
struct ipc_namespace init_ipc_ns = {
.kref = {
/* It's not for this patch to change, but should this be 1? */
.refcount = ATOMIC_INIT(2),
},
#ifdef CONFIG_POSIX_MQUEUE
.mq_mnt = NULL,
.mq_queues_count = 0,
.mq_queues_max = DFLT_QUEUESMAX,
.mq_msg_max = DFLT_MSGMAX,
.mq_msgsize_max = DFLT_MSGSIZEMAX,
#endif
};
atomic_t nr_ipc_ns = ATOMIC_INIT(1);
struct msg_msgseg {
struct msg_msgseg* next;
/* the next part of the message follows immediately */

View File

@ -25,6 +25,7 @@ static struct ipc_namespace *clone_ipc_ns(struct ipc_namespace *old_ns)
sem_init_ns(ns);
msg_init_ns(ns);
shm_init_ns(ns);
mq_init_ns(ns);
/*
* msgmni has already been computed for the new ipc ns.
@ -101,6 +102,7 @@ void free_ipc_ns(struct kref *kref)
sem_exit_ns(ns);
msg_exit_ns(ns);
shm_exit_ns(ns);
mq_exit_ns(ns);
kfree(ns);
atomic_dec(&nr_ipc_ns);

View File

@ -47,15 +47,6 @@ struct ipc_proc_iface {
int (*show)(struct seq_file *, void *);
};
struct ipc_namespace init_ipc_ns = {
.kref = {
.refcount = ATOMIC_INIT(2),
},
};
atomic_t nr_ipc_ns = ATOMIC_INIT(1);
#ifdef CONFIG_MEMORY_HOTPLUG
static void ipc_memory_notifier(struct work_struct *work)

View File

@ -20,6 +20,13 @@ void shm_init (void);
struct ipc_namespace;
#ifdef CONFIG_POSIX_MQUEUE
void mq_exit_ns(struct ipc_namespace *ns);
#else
static inline void mq_exit_ns(struct ipc_namespace *ns) { }
#endif
#ifdef CONFIG_SYSVIPC
void sem_init_ns(struct ipc_namespace *ns);
void msg_init_ns(struct ipc_namespace *ns);
void shm_init_ns(struct ipc_namespace *ns);
@ -27,6 +34,15 @@ void shm_init_ns(struct ipc_namespace *ns);
void sem_exit_ns(struct ipc_namespace *ns);
void msg_exit_ns(struct ipc_namespace *ns);
void shm_exit_ns(struct ipc_namespace *ns);
#else
static inline void sem_init_ns(struct ipc_namespace *ns) { }
static inline void msg_init_ns(struct ipc_namespace *ns) { }
static inline void shm_init_ns(struct ipc_namespace *ns) { }
static inline void sem_exit_ns(struct ipc_namespace *ns) { }
static inline void msg_exit_ns(struct ipc_namespace *ns) { }
static inline void shm_exit_ns(struct ipc_namespace *ns) { }
#endif
/*
* Structure that holds the parameters needed by the ipc operations