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-rw-r--r--arch/ia64/kernel/perfmon.c2
-rw-r--r--drivers/mtd/mtdchar.c2
-rw-r--r--fs/anon_inodes.c2
-rw-r--r--fs/fs_struct.c26
-rw-r--r--fs/internal.h1
-rw-r--r--fs/namei.c24
-rw-r--r--fs/namespace.c242
-rw-r--r--fs/pipe.c2
-rw-r--r--fs/pnode.c4
-rw-r--r--fs/super.c2
-rw-r--r--include/linux/mount.h53
-rw-r--r--include/linux/path.h2
-rw-r--r--net/socket.c19
13 files changed, 283 insertions, 98 deletions
diff --git a/arch/ia64/kernel/perfmon.c b/arch/ia64/kernel/perfmon.c
index 5a24f40bb48..f099b82703d 100644
--- a/arch/ia64/kernel/perfmon.c
+++ b/arch/ia64/kernel/perfmon.c
@@ -1542,7 +1542,7 @@ pfm_exit_smpl_buffer(pfm_buffer_fmt_t *fmt)
* any operations on the root directory. However, we need a non-trivial
* d_name - pfm: will go nicely and kill the special-casing in procfs.
*/
-static struct vfsmount *pfmfs_mnt;
+static struct vfsmount *pfmfs_mnt __read_mostly;
static int __init
init_pfm_fs(void)
diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c
index 4759d827e8c..f511dd15fd3 100644
--- a/drivers/mtd/mtdchar.c
+++ b/drivers/mtd/mtdchar.c
@@ -1201,7 +1201,7 @@ err_unregister_chdev:
static void __exit cleanup_mtdchar(void)
{
unregister_mtd_user(&mtdchar_notifier);
- mntput(mtd_inode_mnt);
+ mntput_long(mtd_inode_mnt);
unregister_filesystem(&mtd_inodefs_type);
__unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
}
diff --git a/fs/anon_inodes.c b/fs/anon_inodes.c
index 9d92b33da8a..5fd38112a6c 100644
--- a/fs/anon_inodes.c
+++ b/fs/anon_inodes.c
@@ -232,7 +232,7 @@ static int __init anon_inode_init(void)
return 0;
err_mntput:
- mntput(anon_inode_mnt);
+ mntput_long(anon_inode_mnt);
err_unregister_filesystem:
unregister_filesystem(&anon_inode_fs_type);
err_exit:
diff --git a/fs/fs_struct.c b/fs/fs_struct.c
index 60b8531f41c..68ca487bedb 100644
--- a/fs/fs_struct.c
+++ b/fs/fs_struct.c
@@ -17,11 +17,11 @@ void set_fs_root(struct fs_struct *fs, struct path *path)
write_seqcount_begin(&fs->seq);
old_root = fs->root;
fs->root = *path;
- path_get(path);
+ path_get_long(path);
write_seqcount_end(&fs->seq);
spin_unlock(&fs->lock);
if (old_root.dentry)
- path_put(&old_root);
+ path_put_long(&old_root);
}
/*
@@ -36,12 +36,12 @@ void set_fs_pwd(struct fs_struct *fs, struct path *path)
write_seqcount_begin(&fs->seq);
old_pwd = fs->pwd;
fs->pwd = *path;
- path_get(path);
+ path_get_long(path);
write_seqcount_end(&fs->seq);
spin_unlock(&fs->lock);
if (old_pwd.dentry)
- path_put(&old_pwd);
+ path_put_long(&old_pwd);
}
void chroot_fs_refs(struct path *old_root, struct path *new_root)
@@ -59,13 +59,13 @@ void chroot_fs_refs(struct path *old_root, struct path *new_root)
write_seqcount_begin(&fs->seq);
if (fs->root.dentry == old_root->dentry
&& fs->root.mnt == old_root->mnt) {
- path_get(new_root);
+ path_get_long(new_root);
fs->root = *new_root;
count++;
}
if (fs->pwd.dentry == old_root->dentry
&& fs->pwd.mnt == old_root->mnt) {
- path_get(new_root);
+ path_get_long(new_root);
fs->pwd = *new_root;
count++;
}
@@ -76,13 +76,13 @@ void chroot_fs_refs(struct path *old_root, struct path *new_root)
} while_each_thread(g, p);
read_unlock(&tasklist_lock);
while (count--)
- path_put(old_root);
+ path_put_long(old_root);
}
void free_fs_struct(struct fs_struct *fs)
{
- path_put(&fs->root);
- path_put(&fs->pwd);
+ path_put_long(&fs->root);
+ path_put_long(&fs->pwd);
kmem_cache_free(fs_cachep, fs);
}
@@ -115,7 +115,13 @@ struct fs_struct *copy_fs_struct(struct fs_struct *old)
spin_lock_init(&fs->lock);
seqcount_init(&fs->seq);
fs->umask = old->umask;
- get_fs_root_and_pwd(old, &fs->root, &fs->pwd);
+
+ spin_lock(&old->lock);
+ fs->root = old->root;
+ path_get_long(&fs->root);
+ fs->pwd = old->pwd;
+ path_get_long(&fs->pwd);
+ spin_unlock(&old->lock);
}
return fs;
}
diff --git a/fs/internal.h b/fs/internal.h
index e43b9a4dbf4..9687c2ee273 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -63,6 +63,7 @@ extern int copy_mount_string(const void __user *, char **);
extern void free_vfsmnt(struct vfsmount *);
extern struct vfsmount *alloc_vfsmnt(const char *);
+extern unsigned int mnt_get_count(struct vfsmount *mnt);
extern struct vfsmount *__lookup_mnt(struct vfsmount *, struct dentry *, int);
extern void mnt_set_mountpoint(struct vfsmount *, struct dentry *,
struct vfsmount *);
diff --git a/fs/namei.c b/fs/namei.c
index 4e957bf744a..19433cdba01 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -368,6 +368,18 @@ void path_get(struct path *path)
EXPORT_SYMBOL(path_get);
/**
+ * path_get_long - get a long reference to a path
+ * @path: path to get the reference to
+ *
+ * Given a path increment the reference count to the dentry and the vfsmount.
+ */
+void path_get_long(struct path *path)
+{
+ mntget_long(path->mnt);
+ dget(path->dentry);
+}
+
+/**
* path_put - put a reference to a path
* @path: path to put the reference to
*
@@ -381,6 +393,18 @@ void path_put(struct path *path)
EXPORT_SYMBOL(path_put);
/**
+ * path_put_long - put a long reference to a path
+ * @path: path to put the reference to
+ *
+ * Given a path decrement the reference count to the dentry and the vfsmount.
+ */
+void path_put_long(struct path *path)
+{
+ dput(path->dentry);
+ mntput_long(path->mnt);
+}
+
+/**
* nameidata_drop_rcu - drop this nameidata out of rcu-walk
* @nd: nameidata pathwalk data to drop
* @Returns: 0 on success, -ECHLID on failure
diff --git a/fs/namespace.c b/fs/namespace.c
index 03b82350f02..3ddfd9046c4 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -138,6 +138,64 @@ void mnt_release_group_id(struct vfsmount *mnt)
mnt->mnt_group_id = 0;
}
+/*
+ * vfsmount lock must be held for read
+ */
+static inline void mnt_add_count(struct vfsmount *mnt, int n)
+{
+#ifdef CONFIG_SMP
+ this_cpu_add(mnt->mnt_pcp->mnt_count, n);
+#else
+ preempt_disable();
+ mnt->mnt_count += n;
+ preempt_enable();
+#endif
+}
+
+static inline void mnt_set_count(struct vfsmount *mnt, int n)
+{
+#ifdef CONFIG_SMP
+ this_cpu_write(mnt->mnt_pcp->mnt_count, n);
+#else
+ mnt->mnt_count = n;
+#endif
+}
+
+/*
+ * vfsmount lock must be held for read
+ */
+static inline void mnt_inc_count(struct vfsmount *mnt)
+{
+ mnt_add_count(mnt, 1);
+}
+
+/*
+ * vfsmount lock must be held for read
+ */
+static inline void mnt_dec_count(struct vfsmount *mnt)
+{
+ mnt_add_count(mnt, -1);
+}
+
+/*
+ * vfsmount lock must be held for write
+ */
+unsigned int mnt_get_count(struct vfsmount *mnt)
+{
+#ifdef CONFIG_SMP
+ unsigned int count = atomic_read(&mnt->mnt_longrefs);
+ int cpu;
+
+ for_each_possible_cpu(cpu) {
+ count += per_cpu_ptr(mnt->mnt_pcp, cpu)->mnt_count;
+ }
+
+ return count;
+#else
+ return mnt->mnt_count;
+#endif
+}
+
struct vfsmount *alloc_vfsmnt(const char *name)
{
struct vfsmount *mnt = kmem_cache_zalloc(mnt_cache, GFP_KERNEL);
@@ -154,7 +212,17 @@ struct vfsmount *alloc_vfsmnt(const char *name)
goto out_free_id;
}
- atomic_set(&mnt->mnt_count, 1);
+#ifdef CONFIG_SMP
+ mnt->mnt_pcp = alloc_percpu(struct mnt_pcp);
+ if (!mnt->mnt_pcp)
+ goto out_free_devname;
+
+ atomic_set(&mnt->mnt_longrefs, 1);
+#else
+ mnt->mnt_count = 1;
+ mnt->mnt_writers = 0;
+#endif
+
INIT_LIST_HEAD(&mnt->mnt_hash);
INIT_LIST_HEAD(&mnt->mnt_child);
INIT_LIST_HEAD(&mnt->mnt_mounts);
@@ -166,13 +234,6 @@ struct vfsmount *alloc_vfsmnt(const char *name)
#ifdef CONFIG_FSNOTIFY
INIT_HLIST_HEAD(&mnt->mnt_fsnotify_marks);
#endif
-#ifdef CONFIG_SMP
- mnt->mnt_writers = alloc_percpu(int);
- if (!mnt->mnt_writers)
- goto out_free_devname;
-#else
- mnt->mnt_writers = 0;
-#endif
}
return mnt;
@@ -219,7 +280,7 @@ EXPORT_SYMBOL_GPL(__mnt_is_readonly);
static inline void mnt_inc_writers(struct vfsmount *mnt)
{
#ifdef CONFIG_SMP
- (*per_cpu_ptr(mnt->mnt_writers, smp_processor_id()))++;
+ this_cpu_inc(mnt->mnt_pcp->mnt_writers);
#else
mnt->mnt_writers++;
#endif
@@ -228,7 +289,7 @@ static inline void mnt_inc_writers(struct vfsmount *mnt)
static inline void mnt_dec_writers(struct vfsmount *mnt)
{
#ifdef CONFIG_SMP
- (*per_cpu_ptr(mnt->mnt_writers, smp_processor_id()))--;
+ this_cpu_dec(mnt->mnt_pcp->mnt_writers);
#else
mnt->mnt_writers--;
#endif
@@ -241,7 +302,7 @@ static unsigned int mnt_get_writers(struct vfsmount *mnt)
int cpu;
for_each_possible_cpu(cpu) {
- count += *per_cpu_ptr(mnt->mnt_writers, cpu);
+ count += per_cpu_ptr(mnt->mnt_pcp, cpu)->mnt_writers;
}
return count;
@@ -418,7 +479,7 @@ void free_vfsmnt(struct vfsmount *mnt)
kfree(mnt->mnt_devname);
mnt_free_id(mnt);
#ifdef CONFIG_SMP
- free_percpu(mnt->mnt_writers);
+ free_percpu(mnt->mnt_pcp);
#endif
kmem_cache_free(mnt_cache, mnt);
}
@@ -652,9 +713,10 @@ static struct vfsmount *clone_mnt(struct vfsmount *old, struct dentry *root,
return NULL;
}
-static inline void __mntput(struct vfsmount *mnt)
+static inline void mntfree(struct vfsmount *mnt)
{
struct super_block *sb = mnt->mnt_sb;
+
/*
* This probably indicates that somebody messed
* up a mnt_want/drop_write() pair. If this
@@ -662,8 +724,8 @@ static inline void __mntput(struct vfsmount *mnt)
* to make r/w->r/o transitions.
*/
/*
- * atomic_dec_and_lock() used to deal with ->mnt_count decrements
- * provides barriers, so mnt_get_writers() below is safe. AV
+ * The locking used to deal with mnt_count decrement provides barriers,
+ * so mnt_get_writers() below is safe.
*/
WARN_ON(mnt_get_writers(mnt));
fsnotify_vfsmount_delete(mnt);
@@ -672,28 +734,113 @@ static inline void __mntput(struct vfsmount *mnt)
deactivate_super(sb);
}
-void mntput_no_expire(struct vfsmount *mnt)
-{
-repeat:
- if (atomic_add_unless(&mnt->mnt_count, -1, 1))
- return;
+#ifdef CONFIG_SMP
+static inline void __mntput(struct vfsmount *mnt, int longrefs)
+{
+ if (!longrefs) {
+put_again:
+ br_read_lock(vfsmount_lock);
+ if (likely(atomic_read(&mnt->mnt_longrefs))) {
+ mnt_dec_count(mnt);
+ br_read_unlock(vfsmount_lock);
+ return;
+ }
+ br_read_unlock(vfsmount_lock);
+ } else {
+ BUG_ON(!atomic_read(&mnt->mnt_longrefs));
+ if (atomic_add_unless(&mnt->mnt_longrefs, -1, 1))
+ return;
+ }
+
br_write_lock(vfsmount_lock);
- if (!atomic_dec_and_test(&mnt->mnt_count)) {
+ if (!longrefs)
+ mnt_dec_count(mnt);
+ else
+ atomic_dec(&mnt->mnt_longrefs);
+ if (mnt_get_count(mnt)) {
br_write_unlock(vfsmount_lock);
return;
}
- if (likely(!mnt->mnt_pinned)) {
+ if (unlikely(mnt->mnt_pinned)) {
+ mnt_add_count(mnt, mnt->mnt_pinned + 1);
+ mnt->mnt_pinned = 0;
br_write_unlock(vfsmount_lock);
- __mntput(mnt);
+ acct_auto_close_mnt(mnt);
+ goto put_again;
+ }
+ br_write_unlock(vfsmount_lock);
+ mntfree(mnt);
+}
+#else
+static inline void __mntput(struct vfsmount *mnt, int longrefs)
+{
+put_again:
+ mnt_dec_count(mnt);
+ if (likely(mnt_get_count(mnt)))
return;
+ br_write_lock(vfsmount_lock);
+ if (unlikely(mnt->mnt_pinned)) {
+ mnt_add_count(mnt, mnt->mnt_pinned + 1);
+ mnt->mnt_pinned = 0;
+ br_write_unlock(vfsmount_lock);
+ acct_auto_close_mnt(mnt);
+ goto put_again;
}
- atomic_add(mnt->mnt_pinned + 1, &mnt->mnt_count);
- mnt->mnt_pinned = 0;
br_write_unlock(vfsmount_lock);
- acct_auto_close_mnt(mnt);
- goto repeat;
+ mntfree(mnt);
+}
+#endif
+
+static void mntput_no_expire(struct vfsmount *mnt)
+{
+ __mntput(mnt, 0);
+}
+
+void mntput(struct vfsmount *mnt)
+{
+ if (mnt) {
+ /* avoid cacheline pingpong, hope gcc doesn't get "smart" */
+ if (unlikely(mnt->mnt_expiry_mark))
+ mnt->mnt_expiry_mark = 0;
+ __mntput(mnt, 0);
+ }
+}
+EXPORT_SYMBOL(mntput);
+
+struct vfsmount *mntget(struct vfsmount *mnt)
+{
+ if (mnt)
+ mnt_inc_count(mnt);
+ return mnt;
+}
+EXPORT_SYMBOL(mntget);
+
+void mntput_long(struct vfsmount *mnt)
+{
+#ifdef CONFIG_SMP
+ if (mnt) {
+ /* avoid cacheline pingpong, hope gcc doesn't get "smart" */
+ if (unlikely(mnt->mnt_expiry_mark))
+ mnt->mnt_expiry_mark = 0;
+ __mntput(mnt, 1);
+ }
+#else
+ mntput(mnt);
+#endif
}
-EXPORT_SYMBOL(mntput_no_expire);
+EXPORT_SYMBOL(mntput_long);
+
+struct vfsmount *mntget_long(struct vfsmount *mnt)
+{
+#ifdef CONFIG_SMP
+ if (mnt)
+ atomic_inc(&mnt->mnt_longrefs);
+ return mnt;
+#else
+ return mntget(mnt);
+#endif
+}
+EXPORT_SYMBOL(mntget_long);
void mnt_pin(struct vfsmount *mnt)
{
@@ -701,19 +848,17 @@ void mnt_pin(struct vfsmount *mnt)
mnt->mnt_pinned++;
br_write_unlock(vfsmount_lock);
}
-
EXPORT_SYMBOL(mnt_pin);
void mnt_unpin(struct vfsmount *mnt)
{
br_write_lock(vfsmount_lock);
if (mnt->mnt_pinned) {
- atomic_inc(&mnt->mnt_count);
+ mnt_inc_count(mnt);
mnt->mnt_pinned--;
}
br_write_unlock(vfsmount_lock);
}
-
EXPORT_SYMBOL(mnt_unpin);
static inline void mangle(struct seq_file *m, const char *s)
@@ -1008,12 +1153,13 @@ int may_umount_tree(struct vfsmount *mnt)
int minimum_refs = 0;
struct vfsmount *p;
- br_read_lock(vfsmount_lock);
+ /* write lock needed for mnt_get_count */
+ br_write_lock(vfsmount_lock);
for (p = mnt; p; p = next_mnt(p, mnt)) {
- actual_refs += atomic_read(&p->mnt_count);
+ actual_refs += mnt_get_count(p);
minimum_refs += 2;
}
- br_read_unlock(vfsmount_lock);
+ br_write_unlock(vfsmount_lock);
if (actual_refs > minimum_refs)
return 0;
@@ -1040,10 +1186,10 @@ int may_umount(struct vfsmount *mnt)
{
int ret = 1;
down_read(&namespace_sem);
- br_read_lock(vfsmount_lock);
+ br_write_lock(vfsmount_lock);
if (propagate_mount_busy(mnt, 2))
ret = 0;
- br_read_unlock(vfsmount_lock);
+ br_write_unlock(vfsmount_lock);
up_read(&namespace_sem);
return ret;
}
@@ -1070,7 +1216,7 @@ void release_mounts(struct list_head *head)
dput(dentry);
mntput(m);
}
- mntput(mnt);
+ mntput_long(mnt);
}
}
@@ -1125,8 +1271,16 @@ static int do_umount(struct vfsmount *mnt, int flags)
flags & (MNT_FORCE | MNT_DETACH))
return -EINVAL;
- if (atomic_read(&mnt->mnt_count) != 2)
+ /*
+ * probably don't strictly need the lock here if we examined
+ * all race cases, but it's a slowpath.
+ */
+ br_write_lock(vfsmount_lock);
+ if (mnt_get_count(mnt) != 2) {
+ br_write_lock(vfsmount_lock);
return -EBUSY;
+ }
+ br_write_unlock(vfsmount_lock);
if (!xchg(&mnt->mnt_expiry_mark, 1))
return -EAGAIN;
@@ -1815,7 +1969,7 @@ int do_add_mount(struct vfsmount *newmnt, struct path *path,
unlock:
up_write(&namespace_sem);
- mntput(newmnt);
+ mntput_long(newmnt);
return err;
}
@@ -2148,11 +2302,11 @@ static struct mnt_namespace *dup_mnt_ns(struct mnt_namespace *mnt_ns,
if (fs) {
if (p == fs->root.mnt) {
rootmnt = p;
- fs->root.mnt = mntget(q);
+ fs->root.mnt = mntget_long(q);
}
if (p == fs->pwd.mnt) {
pwdmnt = p;
- fs->pwd.mnt = mntget(q);
+ fs->pwd.mnt = mntget_long(q);
}
}
p = next_mnt(p, mnt_ns->root);
@@ -2161,9 +2315,9 @@ static struct mnt_namespace *dup_mnt_ns(struct mnt_namespace *mnt_ns,
up_write(&namespace_sem);
if (rootmnt)
- mntput(rootmnt);
+ mntput_long(rootmnt);
if (pwdmnt)
- mntput(pwdmnt);
+ mntput_long(pwdmnt);
return new_ns;
}
@@ -2350,6 +2504,7 @@ SYSCALL_DEFINE2(pivot_root, const char __user *, new_root,
touch_mnt_namespace(current->nsproxy->mnt_ns);
br_write_unlock(vfsmount_lock);
chroot_fs_refs(&root, &new);
+
error = 0;
path_put(&root_parent);
path_put(&parent_path);
@@ -2376,6 +2531,7 @@ static void __init init_mount_tree(void)
mnt = do_kern_mount("rootfs", 0, "rootfs", NULL);
if (IS_ERR(mnt))
panic("Can't create rootfs");
+
ns = create_mnt_ns(mnt);
if (IS_ERR(ns))
panic("Can't allocate initial namespace");
diff --git a/fs/pipe.c b/fs/pipe.c
index cfe3a7f2ee2..68f1f8e4e23 100644
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -1292,7 +1292,7 @@ static int __init init_pipe_fs(void)
static void __exit exit_pipe_fs(void)
{
unregister_filesystem(&pipe_fs_type);
- mntput(pipe_mnt);
+ mntput_long(pipe_mnt);
}
fs_initcall(init_pipe_fs);
diff --git a/fs/pnode.c b/fs/pnode.c
index 8066b8dd748..d42514e3238 100644
--- a/fs/pnode.c
+++ b/fs/pnode.c
@@ -288,7 +288,7 @@ out:
*/
static inline int do_refcount_check(struct vfsmount *mnt, int count)
{
- int mycount = atomic_read(&mnt->mnt_count) - mnt->mnt_ghosts;
+ int mycount = mnt_get_count(mnt) - mnt->mnt_ghosts;
return (mycount > count);
}
@@ -300,7 +300,7 @@ static inline int do_refcount_check(struct vfsmount *mnt, int count)
* Check if any of these mounts that **do not have submounts**
* have more references than 'refcnt'. If so return busy.
*
- * vfsmount lock must be held for read or write
+ * vfsmount lock must be held for write
*/
int propagate_mount_busy(struct vfsmount *mnt, int refcnt)
{
diff --git a/fs/super.c b/fs/super.c
index 968ba013011..823e061faa8 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -1140,7 +1140,7 @@ static struct vfsmount *fs_set_subtype(struct vfsmount *mnt, const char *fstype)
return mnt;
err:
- mntput(mnt);
+ mntput_long(mnt);
return ERR_PTR(err);
}
diff --git a/include/linux/mount.h b/include/linux/mount.h
index 5e7a59408dd..1869ea24a73 100644
--- a/include/linux/mount.h
+++ b/include/linux/mount.h
@@ -13,6 +13,7 @@
#include <linux/list.h>
#include <linux/nodemask.h>
#include <linux/spinlock.h>
+#include <linux/seqlock.h>
#include <asm/atomic.h>
struct super_block;
@@ -46,12 +47,24 @@ struct mnt_namespace;
#define MNT_INTERNAL 0x4000
+struct mnt_pcp {
+ int mnt_count;
+ int mnt_writers;
+};
+
struct vfsmount {
struct list_head mnt_hash;
struct vfsmount *mnt_parent; /* fs we are mounted on */
struct dentry *mnt_mountpoint; /* dentry of mountpoint */
struct dentry *mnt_root; /* root of the mounted tree */
struct super_block *mnt_sb; /* pointer to superblock */
+#ifdef CONFIG_SMP
+ struct mnt_pcp __percpu *mnt_pcp;
+ atomic_t mnt_longrefs;
+#else
+ int mnt_count;
+ int mnt_writers;
+#endif
struct list_head mnt_mounts; /* list of children, anchored here */
struct list_head mnt_child; /* and going through their mnt_child */
int mnt_flags;
@@ -70,57 +83,25 @@ struct vfsmount {
struct mnt_namespace *mnt_ns; /* containing namespace */
int mnt_id; /* mount identifier */
int mnt_group_id; /* peer group identifier */
- /*
- * We put mnt_count & mnt_expiry_mark at the end of struct vfsmount
- * to let these frequently modified fields in a separate cache line
- * (so that reads of mnt_flags wont ping-pong on SMP machines)
- */
- atomic_t mnt_count;
int mnt_expiry_mark; /* true if marked for expiry */
int mnt_pinned;
int mnt_ghosts;
-#ifdef CONFIG_SMP
- int __percpu *mnt_writers;
-#else
- int mnt_writers;
-#endif
};
-static inline int *get_mnt_writers_ptr(struct vfsmount *mnt)
-{
-#ifdef CONFIG_SMP
- return mnt->mnt_writers;
-#else
- return &mnt->mnt_writers;
-#endif
-}
-
-static inline struct vfsmount *mntget(struct vfsmount *mnt)
-{
- if (mnt)
- atomic_inc(&mnt->mnt_count);
- return mnt;
-}
-
struct file; /* forward dec */
extern int mnt_want_write(struct vfsmount *mnt);
extern int mnt_want_write_file(struct file *file);
extern int mnt_clone_write(struct vfsmount *mnt);
extern void mnt_drop_write(struct vfsmount *mnt);
-extern void mntput_no_expire(struct vfsmount *mnt);
+extern void mntput(struct vfsmount *mnt);
+extern struct vfsmount *mntget(struct vfsmount *mnt);
+extern void mntput_long(struct vfsmount *mnt);
+extern struct vfsmount *mntget_long(struct vfsmount *mnt);
extern void mnt_pin(struct vfsmount *mnt);
extern void mnt_unpin(struct vfsmount *mnt);
extern int __mnt_is_readonly(struct vfsmount *mnt);
-static inline void mntput(struct vfsmount *mnt)
-{
- if (mnt) {
- mnt->mnt_expiry_mark = 0;
- mntput_no_expire(mnt);
- }
-}
-
extern struct vfsmount *do_kern_mount(const char *fstype, int flags,
const char *name, void *data);
diff --git a/include/linux/path.h b/include/linux/path.h
index edc98dec626..a581e8c0653 100644
--- a/include/linux/path.h
+++ b/include/linux/path.h
@@ -10,7 +10,9 @@ struct path {
};
extern void path_get(struct path *);
+extern void path_get_long(struct path *);
extern void path_put(struct path *);
+extern void path_put_long(struct path *);
static inline int path_equal(const struct path *path1, const struct path *path2)
{
diff --git a/net/socket.c b/net/socket.c
index 0ee74c32532..815bba3d2fe 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -2390,6 +2390,8 @@ EXPORT_SYMBOL(sock_unregister);
static int __init sock_init(void)
{
+ int err;
+
/*
* Initialize sock SLAB cache.
*/
@@ -2406,8 +2408,15 @@ static int __init sock_init(void)
*/
init_inodecache();
- register_filesystem(&sock_fs_type);
+
+ err = register_filesystem(&sock_fs_type);
+ if (err)
+ goto out_fs;
sock_mnt = kern_mount(&sock_fs_type);
+ if (IS_ERR(sock_mnt)) {
+ err = PTR_ERR(sock_mnt);
+ goto out_mount;
+ }
/* The real protocol initialization is performed in later initcalls.
*/
@@ -2420,7 +2429,13 @@ static int __init sock_init(void)
skb_timestamping_init();
#endif
- return 0;
+out:
+ return err;
+
+out_mount:
+ unregister_filesystem(&sock_fs_type);
+out_fs:
+ goto out;
}
core_initcall(sock_init); /* early initcall */