diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/fuse/dev.c | 35 | ||||
| -rw-r--r-- | fs/fuse/fuse_i.h | 12 | ||||
| -rw-r--r-- | fs/fuse/inode.c | 40 |
3 files changed, 47 insertions, 40 deletions
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c index cc750c68fe70..104a62dadb94 100644 --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -128,14 +128,24 @@ void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req) } } -void fuse_remove_background(struct fuse_conn *fc, struct fuse_req *req) +/* + * Called with sbput_sem held for read (request_end) or write + * (fuse_put_super). By the time fuse_put_super() is finished, all + * inodes belonging to background requests must be released, so the + * iputs have to be done within the locked region. + */ +void fuse_release_background(struct fuse_conn *fc, struct fuse_req *req) { - list_del_init(&req->bg_entry); + iput(req->inode); + iput(req->inode2); + spin_lock(&fc->lock); + list_del(&req->bg_entry); if (fc->num_background == FUSE_MAX_BACKGROUND) { fc->blocked = 0; wake_up_all(&fc->blocked_waitq); } fc->num_background--; + spin_unlock(&fc->lock); } /* @@ -165,27 +175,22 @@ static void request_end(struct fuse_conn *fc, struct fuse_req *req) wake_up(&req->waitq); fuse_put_request(fc, req); } else { - struct inode *inode = req->inode; - struct inode *inode2 = req->inode2; - struct file *file = req->file; void (*end) (struct fuse_conn *, struct fuse_req *) = req->end; req->end = NULL; - req->inode = NULL; - req->inode2 = NULL; - req->file = NULL; - if (!list_empty(&req->bg_entry)) - fuse_remove_background(fc, req); spin_unlock(&fc->lock); + down_read(&fc->sbput_sem); + if (fc->mounted) + fuse_release_background(fc, req); + up_read(&fc->sbput_sem); + + /* fput must go outside sbput_sem, otherwise it can deadlock */ + if (req->file) + fput(req->file); if (end) end(fc, req); else fuse_put_request(fc, req); - - if (file) - fput(file); - iput(inode); - iput(inode2); } } diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h index 59661c481d9d..0474202cb5dc 100644 --- a/fs/fuse/fuse_i.h +++ b/fs/fuse/fuse_i.h @@ -258,9 +258,15 @@ struct fuse_conn { /** waitq for blocked connection */ wait_queue_head_t blocked_waitq; + /** RW semaphore for exclusion with fuse_put_super() */ + struct rw_semaphore sbput_sem; + /** The next unique request id */ u64 reqctr; + /** Mount is active */ + unsigned mounted; + /** Connection established, cleared on umount, connection abort and device release */ unsigned connected; @@ -471,11 +477,11 @@ void request_send_noreply(struct fuse_conn *fc, struct fuse_req *req); void request_send_background(struct fuse_conn *fc, struct fuse_req *req); /** - * Remove request from the the background list + * Release inodes and file associated with background request */ -void fuse_remove_background(struct fuse_conn *fc, struct fuse_req *req); +void fuse_release_background(struct fuse_conn *fc, struct fuse_req *req); -/** Abort all requests */ +/* Abort all requests */ void fuse_abort_conn(struct fuse_conn *fc); /** diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c index 43a6fc0db8a7..7627022446b2 100644 --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -204,26 +204,17 @@ static void fuse_put_super(struct super_block *sb) { struct fuse_conn *fc = get_fuse_conn_super(sb); + down_write(&fc->sbput_sem); + while (!list_empty(&fc->background)) + fuse_release_background(fc, + list_entry(fc->background.next, + struct fuse_req, bg_entry)); + spin_lock(&fc->lock); + fc->mounted = 0; fc->connected = 0; - while (!list_empty(&fc->background)) { - struct fuse_req *req = list_entry(fc->background.next, - struct fuse_req, bg_entry); - struct inode *inode = req->inode; - struct inode *inode2 = req->inode2; - - /* File would hold a reference to vfsmount */ - BUG_ON(req->file); - req->inode = NULL; - req->inode2 = NULL; - fuse_remove_background(fc, req); - - spin_unlock(&fc->lock); - iput(inode); - iput(inode2); - spin_lock(&fc->lock); - } spin_unlock(&fc->lock); + up_write(&fc->sbput_sem); /* Flush all readers on this fs */ kill_fasync(&fc->fasync, SIGIO, POLL_IN); wake_up_all(&fc->waitq); @@ -395,6 +386,7 @@ static struct fuse_conn *new_conn(void) INIT_LIST_HEAD(&fc->processing); INIT_LIST_HEAD(&fc->io); INIT_LIST_HEAD(&fc->background); + init_rwsem(&fc->sbput_sem); kobj_set_kset_s(fc, connections_subsys); kobject_init(&fc->kobj); atomic_set(&fc->num_waiting, 0); @@ -508,11 +500,6 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent) if (file->f_op != &fuse_dev_operations) return -EINVAL; - /* Setting file->private_data can't race with other mount() - instances, since BKL is held for ->get_sb() */ - if (file->private_data) - return -EINVAL; - fc = new_conn(); if (!fc) return -ENOMEM; @@ -548,7 +535,14 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent) if (err) goto err_free_req; + /* Setting file->private_data can't race with other mount() + instances, since BKL is held for ->get_sb() */ + err = -EINVAL; + if (file->private_data) + goto err_kobject_del; + sb->s_root = root_dentry; + fc->mounted = 1; fc->connected = 1; kobject_get(&fc->kobj); file->private_data = fc; @@ -563,6 +557,8 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent) return 0; + err_kobject_del: + kobject_del(&fc->kobj); err_free_req: fuse_request_free(init_req); err_put_root: |