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| author | Amir Goldstein <amir73il@gmail.com> | 2017-01-17 06:34:56 +0200 |
|---|---|---|
| committer | Miklos Szeredi <mszeredi@redhat.com> | 2017-02-07 15:47:14 +0100 |
| commit | 39d3d60a54df05a1a32fa71159d7a26a530dee6c (patch) | |
| tree | 176b1873dbc9d1a96abccf597ca91c82d27de87d /fs/overlayfs | |
| parent | d8514d8edb5b045cf7f708e14f888ce760d60f0b (diff) | |
| download | linux-39d3d60a54df05a1a32fa71159d7a26a530dee6c.tar.gz | |
ovl: introduce copy up waitqueue
The overlay sb 'copyup_wq' and overlay inode 'copying' condition variable are about to replace the upper sb rename_lock, as finer grained synchronization objects for concurrent copy up. Suggested-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Diffstat (limited to 'fs/overlayfs')
| -rw-r--r-- | fs/overlayfs/overlayfs.h | 2 | ||||
| -rw-r--r-- | fs/overlayfs/ovl_entry.h | 2 | ||||
| -rw-r--r-- | fs/overlayfs/super.c | 1 | ||||
| -rw-r--r-- | fs/overlayfs/util.c | 30 |
4 files changed, 35 insertions, 0 deletions
diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h index 3822a909ce1f..741dc0b6931f 100644 --- a/fs/overlayfs/overlayfs.h +++ b/fs/overlayfs/overlayfs.h @@ -178,6 +178,8 @@ void ovl_dentry_version_inc(struct dentry *dentry); u64 ovl_dentry_version_get(struct dentry *dentry); bool ovl_is_whiteout(struct dentry *dentry); struct file *ovl_path_open(struct path *path, int flags); +int ovl_copy_up_start(struct dentry *dentry); +void ovl_copy_up_end(struct dentry *dentry); /* namei.c */ int ovl_path_next(int idx, struct dentry *dentry, struct path *path); diff --git a/fs/overlayfs/ovl_entry.h b/fs/overlayfs/ovl_entry.h index 65f240001aa6..59614faa14c3 100644 --- a/fs/overlayfs/ovl_entry.h +++ b/fs/overlayfs/ovl_entry.h @@ -28,6 +28,7 @@ struct ovl_fs { /* creds of process who forced instantiation of super block */ const struct cred *creator_cred; bool tmpfile; + wait_queue_head_t copyup_wq; }; /* private information held for every overlayfs dentry */ @@ -39,6 +40,7 @@ struct ovl_entry { u64 version; const char *redirect; bool opaque; + bool copying; }; struct rcu_head rcu; }; diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index ff05065b510f..6792bb70b4ac 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -708,6 +708,7 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent) if (!ufs) goto out; + init_waitqueue_head(&ufs->copyup_wq); ufs->config.redirect_dir = ovl_redirect_dir_def; err = ovl_parse_opt((char *) data, &ufs->config); if (err) diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c index 952286f4826c..01157d6e8cfe 100644 --- a/fs/overlayfs/util.c +++ b/fs/overlayfs/util.c @@ -263,3 +263,33 @@ struct file *ovl_path_open(struct path *path, int flags) { return dentry_open(path, flags | O_NOATIME, current_cred()); } + +int ovl_copy_up_start(struct dentry *dentry) +{ + struct ovl_fs *ofs = dentry->d_sb->s_fs_info; + struct ovl_entry *oe = dentry->d_fsdata; + int err; + + spin_lock(&ofs->copyup_wq.lock); + err = wait_event_interruptible_locked(ofs->copyup_wq, !oe->copying); + if (!err) { + if (oe->__upperdentry) + err = 1; /* Already copied up */ + else + oe->copying = true; + } + spin_unlock(&ofs->copyup_wq.lock); + + return err; +} + +void ovl_copy_up_end(struct dentry *dentry) +{ + struct ovl_fs *ofs = dentry->d_sb->s_fs_info; + struct ovl_entry *oe = dentry->d_fsdata; + + spin_lock(&ofs->copyup_wq.lock); + oe->copying = false; + wake_up_locked(&ofs->copyup_wq); + spin_unlock(&ofs->copyup_wq.lock); +} |