diff options
| -rw-r--r-- | fs/fuse/dev.c | 119 |
1 files changed, 46 insertions, 73 deletions
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c index e5901bf8d600..3b979abb7b54 100644 --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -382,8 +382,8 @@ __releases(fc->lock) { void (*end) (struct fuse_conn *, struct fuse_req *) = req->end; req->end = NULL; - list_del(&req->list); - list_del(&req->intr_entry); + list_del_init(&req->list); + list_del_init(&req->intr_entry); req->state = FUSE_REQ_FINISHED; if (req->background) { req->background = 0; @@ -439,8 +439,6 @@ __acquires(fc->lock) /* Any signal may interrupt this */ wait_answer_interruptible(fc, req); - if (req->aborted) - goto aborted; if (req->state == FUSE_REQ_FINISHED) return; @@ -457,8 +455,6 @@ __acquires(fc->lock) wait_answer_interruptible(fc, req); restore_sigs(&oldset); - if (req->aborted) - goto aborted; if (req->state == FUSE_REQ_FINISHED) return; @@ -478,22 +474,6 @@ __acquires(fc->lock) spin_unlock(&fc->lock); wait_event(req->waitq, req->state == FUSE_REQ_FINISHED); spin_lock(&fc->lock); - - if (!req->aborted) - return; - - aborted: - BUG_ON(req->state != FUSE_REQ_FINISHED); - if (req->locked) { - /* This is uninterruptible sleep, because data is - being copied to/from the buffers of req. During - locked state, there mustn't be any filesystem - operation (e.g. page fault), since that could lead - to deadlock */ - spin_unlock(&fc->lock); - wait_event(req->waitq, !req->locked); - spin_lock(&fc->lock); - } } static void __fuse_request_send(struct fuse_conn *fc, struct fuse_req *req) @@ -690,19 +670,21 @@ static int lock_request(struct fuse_conn *fc, struct fuse_req *req) } /* - * Unlock request. If it was aborted during being locked, the - * requester thread is currently waiting for it to be unlocked, so - * wake it up. + * Unlock request. If it was aborted while locked, caller is responsible + * for unlocking and ending the request. */ -static void unlock_request(struct fuse_conn *fc, struct fuse_req *req) +static int unlock_request(struct fuse_conn *fc, struct fuse_req *req) { + int err = 0; if (req) { spin_lock(&fc->lock); - req->locked = 0; if (req->aborted) - wake_up(&req->waitq); + err = -ENOENT; + else + req->locked = 0; spin_unlock(&fc->lock); } + return err; } struct fuse_copy_state { @@ -759,7 +741,10 @@ static int fuse_copy_fill(struct fuse_copy_state *cs) struct page *page; int err; - unlock_request(cs->fc, cs->req); + err = unlock_request(cs->fc, cs->req); + if (err) + return err; + fuse_copy_finish(cs); if (cs->pipebufs) { struct pipe_buffer *buf = cs->pipebufs; @@ -859,7 +844,10 @@ static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep) struct page *newpage; struct pipe_buffer *buf = cs->pipebufs; - unlock_request(cs->fc, cs->req); + err = unlock_request(cs->fc, cs->req); + if (err) + return err; + fuse_copy_finish(cs); err = buf->ops->confirm(cs->pipe, buf); @@ -949,11 +937,15 @@ static int fuse_ref_page(struct fuse_copy_state *cs, struct page *page, unsigned offset, unsigned count) { struct pipe_buffer *buf; + int err; if (cs->nr_segs == cs->pipe->buffers) return -EIO; - unlock_request(cs->fc, cs->req); + err = unlock_request(cs->fc, cs->req); + if (err) + return err; + fuse_copy_finish(cs); buf = cs->pipebufs; @@ -1318,7 +1310,7 @@ static ssize_t fuse_dev_do_read(struct fuse_conn *fc, struct file *file, fuse_copy_finish(cs); spin_lock(&fc->lock); req->locked = 0; - if (req->aborted) { + if (!fc->connected) { request_end(fc, req); return -ENODEV; } @@ -1910,13 +1902,6 @@ static ssize_t fuse_dev_do_write(struct fuse_conn *fc, if (!req) goto err_unlock; - if (req->aborted) { - spin_unlock(&fc->lock); - fuse_copy_finish(cs); - spin_lock(&fc->lock); - request_end(fc, req); - return -ENOENT; - } /* Is it an interrupt reply? */ if (req->intr_unique == oh.unique) { err = -EINVAL; @@ -1947,10 +1932,9 @@ static ssize_t fuse_dev_do_write(struct fuse_conn *fc, spin_lock(&fc->lock); req->locked = 0; - if (!err) { - if (req->aborted) - err = -ENOENT; - } else if (!req->aborted) + if (!fc->connected) + err = -ENOENT; + else if (err) req->out.h.error = -EIO; request_end(fc, req); @@ -2097,37 +2081,31 @@ __acquires(fc->lock) /* * Abort requests under I/O * - * The requests are set to aborted and finished, and the request - * waiter is woken up. This will make request_wait_answer() wait - * until the request is unlocked and then return. + * Separate out unlocked requests, they should be finished off immediately. + * Locked requests will be finished after unlock; see unlock_request(). * - * If the request is asynchronous, then the end function needs to be - * called after waiting for the request to be unlocked (if it was - * locked). + * Next finish off the unlocked requests. It is possible that some request will + * finish before we can. This is OK, the request will in that case be removed + * from the list before we touch it. */ static void end_io_requests(struct fuse_conn *fc) __releases(fc->lock) __acquires(fc->lock) { - while (!list_empty(&fc->io)) { - struct fuse_req *req = - list_entry(fc->io.next, struct fuse_req, list); - void (*end) (struct fuse_conn *, struct fuse_req *) = req->end; + struct fuse_req *req, *next; + LIST_HEAD(to_end); - req->aborted = 1; + list_for_each_entry_safe(req, next, &fc->io, list) { req->out.h.error = -ECONNABORTED; - req->state = FUSE_REQ_FINISHED; - list_del_init(&req->list); - wake_up(&req->waitq); - if (end) { - req->end = NULL; - __fuse_get_request(req); - spin_unlock(&fc->lock); - wait_event(req->waitq, !req->locked); - end(fc, req); - fuse_put_request(fc, req); - spin_lock(&fc->lock); - } + req->aborted = 1; + if (!req->locked) + list_move(&req->list, &to_end); + } + while (!list_empty(&to_end)) { + req = list_first_entry(&to_end, struct fuse_req, list); + __fuse_get_request(req); + request_end(fc, req); + spin_lock(&fc->lock); } } @@ -2169,13 +2147,8 @@ static void end_polls(struct fuse_conn *fc) * is the combination of an asynchronous request and the tricky * deadlock (see Documentation/filesystems/fuse.txt). * - * During the aborting, progression of requests from the pending and - * processing lists onto the io list, and progression of new requests - * onto the pending list is prevented by req->connected being false. - * - * Progression of requests under I/O to the processing list is - * prevented by the req->aborted flag being true for these requests. - * For this reason requests on the io list must be aborted first. + * Request progression from one list to the next is prevented by + * fc->connected being false. */ void fuse_abort_conn(struct fuse_conn *fc) { |