diff options
| -rw-r--r-- | fs/fs_struct.c | 27 |
1 files changed, 15 insertions, 12 deletions
diff --git a/fs/fs_struct.c b/fs/fs_struct.c index 27114b413622..6324c4274959 100644 --- a/fs/fs_struct.c +++ b/fs/fs_struct.c @@ -26,11 +26,11 @@ void set_fs_root(struct fs_struct *fs, struct path *path) { struct path old_root; + path_get_longterm(path); spin_lock(&fs->lock); write_seqcount_begin(&fs->seq); old_root = fs->root; fs->root = *path; - path_get_longterm(path); write_seqcount_end(&fs->seq); spin_unlock(&fs->lock); if (old_root.dentry) @@ -45,11 +45,11 @@ void set_fs_pwd(struct fs_struct *fs, struct path *path) { struct path old_pwd; + path_get_longterm(path); spin_lock(&fs->lock); write_seqcount_begin(&fs->seq); old_pwd = fs->pwd; fs->pwd = *path; - path_get_longterm(path); write_seqcount_end(&fs->seq); spin_unlock(&fs->lock); @@ -57,6 +57,14 @@ void set_fs_pwd(struct fs_struct *fs, struct path *path) path_put_longterm(&old_pwd); } +static inline int replace_path(struct path *p, const struct path *old, const struct path *new) +{ + if (likely(p->dentry != old->dentry || p->mnt != old->mnt)) + return 0; + *p = *new; + return 1; +} + void chroot_fs_refs(struct path *old_root, struct path *new_root) { struct task_struct *g, *p; @@ -68,21 +76,16 @@ void chroot_fs_refs(struct path *old_root, struct path *new_root) task_lock(p); fs = p->fs; if (fs) { + int hits = 0; spin_lock(&fs->lock); write_seqcount_begin(&fs->seq); - if (fs->root.dentry == old_root->dentry - && fs->root.mnt == old_root->mnt) { - path_get_longterm(new_root); - fs->root = *new_root; + hits += replace_path(&fs->root, old_root, new_root); + hits += replace_path(&fs->pwd, old_root, new_root); + write_seqcount_end(&fs->seq); + while (hits--) { count++; - } - if (fs->pwd.dentry == old_root->dentry - && fs->pwd.mnt == old_root->mnt) { path_get_longterm(new_root); - fs->pwd = *new_root; - count++; } - write_seqcount_end(&fs->seq); spin_unlock(&fs->lock); } task_unlock(p); |