From dc00809a53edd15369906b90407a2d5b976289f5 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Wed, 1 Jul 2015 16:25:58 +0200 Subject: [PATCH] fuse: use per req lock for lock/unlock_request() Reuse req->waitq.lock for protecting FR_ABORTED and FR_LOCKED flags. Signed-off-by: Miklos Szeredi Reviewed-by: Ashish Samant --- fs/fuse/dev.c | 42 ++++++++++++++++++++---------------------- fs/fuse/fuse_i.h | 4 ++++ 2 files changed, 24 insertions(+), 22 deletions(-) diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c index dcfef5475ada..92c7691df429 100644 --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -656,16 +656,16 @@ void fuse_force_forget(struct file *file, u64 nodeid) * anything that could cause a page-fault. If the request was already * aborted bail out. */ -static int lock_request(struct fuse_conn *fc, struct fuse_req *req) +static int lock_request(struct fuse_req *req) { int err = 0; if (req) { - spin_lock(&fc->lock); + spin_lock(&req->waitq.lock); if (test_bit(FR_ABORTED, &req->flags)) err = -ENOENT; else set_bit(FR_LOCKED, &req->flags); - spin_unlock(&fc->lock); + spin_unlock(&req->waitq.lock); } return err; } @@ -674,22 +674,21 @@ static int lock_request(struct fuse_conn *fc, struct fuse_req *req) * Unlock request. If it was aborted while locked, caller is responsible * for unlocking and ending the request. */ -static int unlock_request(struct fuse_conn *fc, struct fuse_req *req) +static int unlock_request(struct fuse_req *req) { int err = 0; if (req) { - spin_lock(&fc->lock); + spin_lock(&req->waitq.lock); if (test_bit(FR_ABORTED, &req->flags)) err = -ENOENT; else clear_bit(FR_LOCKED, &req->flags); - spin_unlock(&fc->lock); + spin_unlock(&req->waitq.lock); } return err; } struct fuse_copy_state { - struct fuse_conn *fc; int write; struct fuse_req *req; struct iov_iter *iter; @@ -703,13 +702,10 @@ struct fuse_copy_state { unsigned move_pages:1; }; -static void fuse_copy_init(struct fuse_copy_state *cs, - struct fuse_conn *fc, - int write, +static void fuse_copy_init(struct fuse_copy_state *cs, int write, struct iov_iter *iter) { memset(cs, 0, sizeof(*cs)); - cs->fc = fc; cs->write = write; cs->iter = iter; } @@ -742,7 +738,7 @@ static int fuse_copy_fill(struct fuse_copy_state *cs) struct page *page; int err; - err = unlock_request(cs->fc, cs->req); + err = unlock_request(cs->req); if (err) return err; @@ -794,7 +790,7 @@ static int fuse_copy_fill(struct fuse_copy_state *cs) iov_iter_advance(cs->iter, err); } - return lock_request(cs->fc, cs->req); + return lock_request(cs->req); } /* Do as much copy to/from userspace buffer as we can */ @@ -845,7 +841,7 @@ static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep) struct page *newpage; struct pipe_buffer *buf = cs->pipebufs; - err = unlock_request(cs->fc, cs->req); + err = unlock_request(cs->req); if (err) return err; @@ -902,12 +898,12 @@ static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep) lru_cache_add_file(newpage); err = 0; - spin_lock(&cs->fc->lock); + spin_lock(&cs->req->waitq.lock); if (test_bit(FR_ABORTED, &cs->req->flags)) err = -ENOENT; else *pagep = newpage; - spin_unlock(&cs->fc->lock); + spin_unlock(&cs->req->waitq.lock); if (err) { unlock_page(newpage); @@ -927,7 +923,7 @@ out_fallback: cs->pg = buf->page; cs->offset = buf->offset; - err = lock_request(cs->fc, cs->req); + err = lock_request(cs->req); if (err) return err; @@ -943,7 +939,7 @@ static int fuse_ref_page(struct fuse_copy_state *cs, struct page *page, if (cs->nr_segs == cs->pipe->buffers) return -EIO; - err = unlock_request(cs->fc, cs->req); + err = unlock_request(cs->req); if (err) return err; @@ -1358,7 +1354,7 @@ static ssize_t fuse_dev_read(struct kiocb *iocb, struct iov_iter *to) if (!iter_is_iovec(to)) return -EINVAL; - fuse_copy_init(&cs, fc, 1, to); + fuse_copy_init(&cs, 1, to); return fuse_dev_do_read(fc, file, &cs, iov_iter_count(to)); } @@ -1380,7 +1376,7 @@ static ssize_t fuse_dev_splice_read(struct file *in, loff_t *ppos, if (!bufs) return -ENOMEM; - fuse_copy_init(&cs, fc, 1, NULL); + fuse_copy_init(&cs, 1, NULL); cs.pipebufs = bufs; cs.pipe = pipe; ret = fuse_dev_do_read(fc, in, &cs, len); @@ -1958,7 +1954,7 @@ static ssize_t fuse_dev_write(struct kiocb *iocb, struct iov_iter *from) if (!iter_is_iovec(from)) return -EINVAL; - fuse_copy_init(&cs, fc, 0, from); + fuse_copy_init(&cs, 0, from); return fuse_dev_do_write(fc, &cs, iov_iter_count(from)); } @@ -2023,7 +2019,7 @@ static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe, } pipe_unlock(pipe); - fuse_copy_init(&cs, fc, 0, NULL); + fuse_copy_init(&cs, 0, NULL); cs.pipebufs = bufs; cs.nr_segs = nbuf; cs.pipe = pipe; @@ -2098,9 +2094,11 @@ __acquires(fc->lock) list_for_each_entry_safe(req, next, &fc->io, list) { req->out.h.error = -ECONNABORTED; + spin_lock(&req->waitq.lock); set_bit(FR_ABORTED, &req->flags); if (!test_bit(FR_LOCKED, &req->flags)) list_move(&req->list, &to_end); + spin_unlock(&req->waitq.lock); } while (!list_empty(&to_end)) { req = list_first_entry(&to_end, struct fuse_req, list); diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h index 4503e995c7b2..7257adba7ecd 100644 --- a/fs/fuse/fuse_i.h +++ b/fs/fuse/fuse_i.h @@ -289,6 +289,10 @@ enum fuse_req_flag { /** * A request to the client + * + * .waitq.lock protects the following fields: + * - FR_ABORTED + * - FR_LOCKED (may also be modified under fc->lock, tested under both) */ struct fuse_req { /** This can be on either pending processing or io lists in -- 2.20.1