From patchwork Thu Feb 18 14:02:36 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 12093743 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 579C3C433DB for ; Thu, 18 Feb 2021 17:07:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F281C64DFF for ; Thu, 18 Feb 2021 17:07:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231840AbhBRRGx (ORCPT ); Thu, 18 Feb 2021 12:06:53 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:21711 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233409AbhBROH4 (ORCPT ); Thu, 18 Feb 2021 09:07:56 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1613657185; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=YxxJ29aSymX4Z00nCing50dEBN/DdhwTMSMb6j8OPe4=; b=GwO+rbiXkPGQmPRktjdap7x+slsENqe/p5t22IK4eY/dPw51mIFyiGhmykK5KMqRo8+YW8 Na0TXZD/kHdgXvgMCx4/NtA3KftCHnrCUC3kQvPwUJ8LBlgRiAmUSqjXXOrtKdDXEBfVyl gonRg6FtBu8T87UTNz7FIZydaumjBhM= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-10-ndaNfz4WPi-ih6BZqMZ9cw-1; Thu, 18 Feb 2021 09:02:48 -0500 X-MC-Unique: ndaNfz4WPi-ih6BZqMZ9cw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 44AB6106BBDB; Thu, 18 Feb 2021 14:02:46 +0000 (UTC) Received: from warthog.procyon.org.uk (ovpn-119-68.rdu2.redhat.com [10.10.119.68]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7B241619CA; Thu, 18 Feb 2021 14:02:37 +0000 (UTC) Organization: Red Hat UK Ltd. 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Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: <20210216093044.GA24615@lst.de> References: <20210216093044.GA24615@lst.de> <20210216084230.GA23669@lst.de> <161340385320.1303470.2392622971006879777.stgit@warthog.procyon.org.uk> <1376938.1613429183@warthog.procyon.org.uk> <1419965.1613467771@warthog.procyon.org.uk> To: Christoph Hellwig Cc: dhowells@redhat.com, Trond Myklebust , Marc Dionne , Anna Schumaker , Steve French , Dominique Martinet , linux-cifs@vger.kernel.org, ceph-devel@vger.kernel.org, Jeff Layton , Matthew Wilcox , linux-cachefs@redhat.com, Alexander Viro , linux-mm@kvack.org, linux-afs@lists.infradead.org, v9fs-developer@lists.sourceforge.net, linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org, Jeff Layton , David Wysochanski , linux-kernel@vger.kernel.org, Sebastian Andrzej Siewior Subject: [PATCH 34/33] netfs: Pass flag rather than use in_softirq() MIME-Version: 1.0 Content-ID: <2017128.1613656956.1@warthog.procyon.org.uk> Date: Thu, 18 Feb 2021 14:02:36 +0000 Message-ID: <2017129.1613656956@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org Christoph Hellwig wrote: > On Tue, Feb 16, 2021 at 09:29:31AM +0000, David Howells wrote: > > Is there a better way to do it? The intent is to process the assessment > > phase in the calling thread's context if possible rather than bumping over > > to a worker thread. For synchronous I/O, for example, that's done in the > > caller's thread. Maybe that's the answer - if it's known to be > > asynchronous, I have to punt, but otherwise don't have to. > > Yes, i think you want an explicit flag instead. How about the attached instead? David Tested-by: Marc Dionne Tested-by: Marc Dionne --- commit 29b3e9eed616db01f15c7998c062b4e501ea6582 Author: David Howells Date: Mon Feb 15 21:56:43 2021 +0000 netfs: Pass flag rather than use in_softirq() The in_softirq() in netfs_rreq_terminated() works fine for the cache being on a normal disk, as the completion handlers may get called in softirq context, but for an NVMe drive, the completion handler may get called in IRQ context. Fix to pass a flag to netfs_subreq_terminated() to indicate whether we think the function isn't being called from a context in which we can do allocations, waits and I/O submissions (such as softirq or interrupt context). If this flag is set, netfs lib has to punt to a worker thread to handle anything like that. The symptom involves warnings like the following appearing and the kernel hanging: WARNING: CPU: 0 PID: 0 at kernel/softirq.c:175 __local_bh_enable_ip+0x35/0x50 ... RIP: 0010:__local_bh_enable_ip+0x35/0x50 ... Call Trace: rxrpc_kernel_begin_call+0x7d/0x1b0 [rxrpc] ? afs_rx_new_call+0x40/0x40 [kafs] ? afs_alloc_call+0x28/0x120 [kafs] afs_make_call+0x120/0x510 [kafs] ? afs_rx_new_call+0x40/0x40 [kafs] ? afs_alloc_flat_call+0xba/0x100 [kafs] ? __kmalloc+0x167/0x2f0 ? afs_alloc_flat_call+0x9b/0x100 [kafs] afs_wait_for_operation+0x2d/0x200 [kafs] afs_do_sync_operation+0x16/0x20 [kafs] afs_req_issue_op+0x8c/0xb0 [kafs] netfs_rreq_assess+0x125/0x7d0 [netfs] ? cachefiles_end_operation+0x40/0x40 [cachefiles] netfs_subreq_terminated+0x117/0x220 [netfs] cachefiles_read_complete+0x21/0x60 [cachefiles] iomap_dio_bio_end_io+0xdd/0x110 blk_update_request+0x20a/0x380 blk_mq_end_request+0x1c/0x120 nvme_process_cq+0x159/0x1f0 [nvme] nvme_irq+0x10/0x20 [nvme] __handle_irq_event_percpu+0x37/0x150 handle_irq_event+0x49/0xb0 handle_edge_irq+0x7c/0x200 asm_call_irq_on_stack+0xf/0x20 common_interrupt+0xad/0x120 asm_common_interrupt+0x1e/0x40 ... Reported-by: Marc Dionne Signed-off-by: David Howells cc: Matthew Wilcox cc: linux-mm@kvack.org cc: linux-cachefs@redhat.com cc: linux-afs@lists.infradead.org cc: linux-nfs@vger.kernel.org cc: linux-cifs@vger.kernel.org cc: ceph-devel@vger.kernel.org cc: v9fs-developer@lists.sourceforge.net cc: linux-fsdevel@vger.kernel.org diff --git a/fs/afs/file.c b/fs/afs/file.c index 8f28d4f4cfd7..6dcdbbfb48e2 100644 --- a/fs/afs/file.c +++ b/fs/afs/file.c @@ -223,7 +223,7 @@ static void afs_fetch_data_notify(struct afs_operation *op) if (subreq) { __set_bit(NETFS_SREQ_CLEAR_TAIL, &subreq->flags); - netfs_subreq_terminated(subreq, error ?: req->actual_len); + netfs_subreq_terminated(subreq, error ?: req->actual_len, false); req->subreq = NULL; } else if (req->done) { req->done(req); @@ -289,7 +289,7 @@ static void afs_req_issue_op(struct netfs_read_subrequest *subreq) fsreq = afs_alloc_read(GFP_NOFS); if (!fsreq) - return netfs_subreq_terminated(subreq, -ENOMEM); + return netfs_subreq_terminated(subreq, -ENOMEM, false); fsreq->subreq = subreq; fsreq->pos = subreq->start + subreq->transferred; @@ -304,7 +304,7 @@ static void afs_req_issue_op(struct netfs_read_subrequest *subreq) ret = afs_fetch_data(fsreq->vnode, fsreq); if (ret < 0) - return netfs_subreq_terminated(subreq, ret); + return netfs_subreq_terminated(subreq, ret, false); } static int afs_symlink_readpage(struct page *page) diff --git a/fs/cachefiles/rdwr2.c b/fs/cachefiles/rdwr2.c index 4cea5a2a2d6e..40668bfe6688 100644 --- a/fs/cachefiles/rdwr2.c +++ b/fs/cachefiles/rdwr2.c @@ -23,6 +23,7 @@ struct cachefiles_kiocb { }; netfs_io_terminated_t term_func; void *term_func_priv; + bool was_async; }; static inline void cachefiles_put_kiocb(struct cachefiles_kiocb *ki) @@ -43,10 +44,9 @@ static void cachefiles_read_complete(struct kiocb *iocb, long ret, long ret2) _enter("%ld,%ld", ret, ret2); if (ki->term_func) { - if (ret < 0) - ki->term_func(ki->term_func_priv, ret); - else - ki->term_func(ki->term_func_priv, ki->skipped + ret); + if (ret >= 0) + ret += ki->skipped; + ki->term_func(ki->term_func_priv, ret, ki->was_async); } cachefiles_put_kiocb(ki); @@ -114,6 +114,7 @@ static int cachefiles_read(struct netfs_cache_resources *cres, ki->skipped = skipped; ki->term_func = term_func; ki->term_func_priv = term_func_priv; + ki->was_async = true; if (ki->term_func) ki->iocb.ki_complete = cachefiles_read_complete; @@ -141,6 +142,7 @@ static int cachefiles_read(struct netfs_cache_resources *cres, ret = -EINTR; fallthrough; default: + ki->was_async = false; cachefiles_read_complete(&ki->iocb, ret, 0); if (ret > 0) ret = 0; @@ -156,7 +158,7 @@ static int cachefiles_read(struct netfs_cache_resources *cres, kfree(ki); presubmission_error: if (term_func) - term_func(term_func_priv, ret < 0 ? ret : skipped); + term_func(term_func_priv, ret < 0 ? ret : skipped, false); return ret; } @@ -175,7 +177,7 @@ static void cachefiles_write_complete(struct kiocb *iocb, long ret, long ret2) __sb_end_write(inode->i_sb, SB_FREEZE_WRITE); if (ki->term_func) - ki->term_func(ki->term_func_priv, ret); + ki->term_func(ki->term_func_priv, ret, ki->was_async); cachefiles_put_kiocb(ki); } @@ -214,6 +216,7 @@ static int cachefiles_write(struct netfs_cache_resources *cres, ki->len = len; ki->term_func = term_func; ki->term_func_priv = term_func_priv; + ki->was_async = true; if (ki->term_func) ki->iocb.ki_complete = cachefiles_write_complete; @@ -250,6 +253,7 @@ static int cachefiles_write(struct netfs_cache_resources *cres, ret = -EINTR; /* Fall through */ default: + ki->was_async = false; cachefiles_write_complete(&ki->iocb, ret, 0); if (ret > 0) ret = 0; @@ -265,7 +269,7 @@ static int cachefiles_write(struct netfs_cache_resources *cres, kfree(ki); presubmission_error: if (term_func) - term_func(term_func_priv, -ENOMEM); + term_func(term_func_priv, -ENOMEM, false); return -ENOMEM; } diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c index 0dd64d31eff6..dcfd805d168e 100644 --- a/fs/ceph/addr.c +++ b/fs/ceph/addr.c @@ -221,7 +221,7 @@ static void finish_netfs_read(struct ceph_osd_request *req) if (err >= 0 && err < subreq->len) __set_bit(NETFS_SREQ_CLEAR_TAIL, &subreq->flags); - netfs_subreq_terminated(subreq, err); + netfs_subreq_terminated(subreq, err, true); num_pages = calc_pages_for(osd_data->alignment, osd_data->length); ceph_put_page_vector(osd_data->pages, num_pages, false); @@ -276,7 +276,7 @@ static void ceph_netfs_issue_op(struct netfs_read_subrequest *subreq) out: ceph_osdc_put_request(req); if (err) - netfs_subreq_terminated(subreq, err); + netfs_subreq_terminated(subreq, err, false); dout("%s: result %d\n", __func__, err); } diff --git a/fs/netfs/read_helper.c b/fs/netfs/read_helper.c index 9191a3617d91..5f5de8278499 100644 --- a/fs/netfs/read_helper.c +++ b/fs/netfs/read_helper.c @@ -29,12 +29,13 @@ module_param_named(debug, netfs_debug, uint, S_IWUSR | S_IRUGO); MODULE_PARM_DESC(netfs_debug, "Netfs support debugging mask"); static void netfs_rreq_work(struct work_struct *); -static void __netfs_put_subrequest(struct netfs_read_subrequest *); +static void __netfs_put_subrequest(struct netfs_read_subrequest *, bool); -static void netfs_put_subrequest(struct netfs_read_subrequest *subreq) +static void netfs_put_subrequest(struct netfs_read_subrequest *subreq, + bool was_async) { if (refcount_dec_and_test(&subreq->usage)) - __netfs_put_subrequest(subreq); + __netfs_put_subrequest(subreq, was_async); } static struct netfs_read_request *netfs_alloc_read_request( @@ -67,7 +68,8 @@ static void netfs_get_read_request(struct netfs_read_request *rreq) refcount_inc(&rreq->usage); } -static void netfs_rreq_clear_subreqs(struct netfs_read_request *rreq) +static void netfs_rreq_clear_subreqs(struct netfs_read_request *rreq, + bool was_async) { struct netfs_read_subrequest *subreq; @@ -75,7 +77,7 @@ static void netfs_rreq_clear_subreqs(struct netfs_read_request *rreq) subreq = list_first_entry(&rreq->subrequests, struct netfs_read_subrequest, rreq_link); list_del(&subreq->rreq_link); - netfs_put_subrequest(subreq); + netfs_put_subrequest(subreq, was_async); } } @@ -83,7 +85,7 @@ static void netfs_free_read_request(struct work_struct *work) { struct netfs_read_request *rreq = container_of(work, struct netfs_read_request, work); - netfs_rreq_clear_subreqs(rreq); + netfs_rreq_clear_subreqs(rreq, false); if (rreq->netfs_priv) rreq->netfs_ops->cleanup(rreq->mapping, rreq->netfs_priv); trace_netfs_rreq(rreq, netfs_rreq_trace_free); @@ -93,10 +95,10 @@ static void netfs_free_read_request(struct work_struct *work) netfs_stat_d(&netfs_n_rh_rreq); } -static void netfs_put_read_request(struct netfs_read_request *rreq) +static void netfs_put_read_request(struct netfs_read_request *rreq, bool was_async) { if (refcount_dec_and_test(&rreq->usage)) { - if (in_softirq()) { + if (was_async) { rreq->work.func = netfs_free_read_request; if (!queue_work(system_unbound_wq, &rreq->work)) BUG(); @@ -131,12 +133,15 @@ static void netfs_get_read_subrequest(struct netfs_read_subrequest *subreq) refcount_inc(&subreq->usage); } -static void __netfs_put_subrequest(struct netfs_read_subrequest *subreq) +static void __netfs_put_subrequest(struct netfs_read_subrequest *subreq, + bool was_async) { + struct netfs_read_request *rreq = subreq->rreq; + trace_netfs_sreq(subreq, netfs_sreq_trace_free); - netfs_put_read_request(subreq->rreq); kfree(subreq); netfs_stat_d(&netfs_n_rh_sreq); + netfs_put_read_request(rreq, was_async); } /* @@ -152,11 +157,12 @@ static void netfs_clear_unread(struct netfs_read_subrequest *subreq) iov_iter_zero(iov_iter_count(&iter), &iter); } -static void netfs_cache_read_terminated(void *priv, ssize_t transferred_or_error) +static void netfs_cache_read_terminated(void *priv, ssize_t transferred_or_error, + bool was_async) { struct netfs_read_subrequest *subreq = priv; - netfs_subreq_terminated(subreq, transferred_or_error); + netfs_subreq_terminated(subreq, transferred_or_error, was_async); } /* @@ -186,7 +192,7 @@ static void netfs_fill_with_zeroes(struct netfs_read_request *rreq, { netfs_stat(&netfs_n_rh_zero); __set_bit(NETFS_SREQ_CLEAR_TAIL, &subreq->flags); - netfs_subreq_terminated(subreq, 0); + netfs_subreq_terminated(subreq, 0, false); } /* @@ -215,11 +221,11 @@ static void netfs_read_from_server(struct netfs_read_request *rreq, /* * Release those waiting. */ -static void netfs_rreq_completed(struct netfs_read_request *rreq) +static void netfs_rreq_completed(struct netfs_read_request *rreq, bool was_async) { trace_netfs_rreq(rreq, netfs_rreq_trace_done); - netfs_rreq_clear_subreqs(rreq); - netfs_put_read_request(rreq); + netfs_rreq_clear_subreqs(rreq, was_async); + netfs_put_read_request(rreq, was_async); } /* @@ -228,7 +234,8 @@ static void netfs_rreq_completed(struct netfs_read_request *rreq) * * May be called in softirq mode and we inherit a ref from the caller. */ -static void netfs_rreq_unmark_after_write(struct netfs_read_request *rreq) +static void netfs_rreq_unmark_after_write(struct netfs_read_request *rreq, + bool was_async) { struct netfs_read_subrequest *subreq; struct pagevec pvec; @@ -258,10 +265,11 @@ static void netfs_rreq_unmark_after_write(struct netfs_read_request *rreq) } rcu_read_unlock(); - netfs_rreq_completed(rreq); + netfs_rreq_completed(rreq, was_async); } -static void netfs_rreq_copy_terminated(void *priv, ssize_t transferred_or_error) +static void netfs_rreq_copy_terminated(void *priv, ssize_t transferred_or_error, + bool was_async) { struct netfs_read_subrequest *subreq = priv; struct netfs_read_request *rreq = subreq->rreq; @@ -278,9 +286,9 @@ static void netfs_rreq_copy_terminated(void *priv, ssize_t transferred_or_error) /* If we decrement nr_wr_ops to 0, the ref belongs to us. */ if (atomic_dec_and_test(&rreq->nr_wr_ops)) - netfs_rreq_unmark_after_write(rreq); + netfs_rreq_unmark_after_write(rreq, was_async); - netfs_put_subrequest(subreq); + netfs_put_subrequest(subreq, was_async); } /* @@ -304,7 +312,7 @@ static void netfs_rreq_do_write_to_cache(struct netfs_read_request *rreq) list_for_each_entry_safe(subreq, p, &rreq->subrequests, rreq_link) { if (!test_bit(NETFS_SREQ_WRITE_TO_CACHE, &subreq->flags)) { list_del_init(&subreq->rreq_link); - netfs_put_subrequest(subreq); + netfs_put_subrequest(subreq, false); } } @@ -324,7 +332,7 @@ static void netfs_rreq_do_write_to_cache(struct netfs_read_request *rreq) subreq->len += next->len; subreq->len = round_up(subreq->len, PAGE_SIZE); list_del_init(&next->rreq_link); - netfs_put_subrequest(next); + netfs_put_subrequest(next, false); } iov_iter_xarray(&iter, WRITE, &rreq->mapping->i_pages, @@ -340,7 +348,7 @@ static void netfs_rreq_do_write_to_cache(struct netfs_read_request *rreq) /* If we decrement nr_wr_ops to 0, the usage ref belongs to us. */ if (atomic_dec_and_test(&rreq->nr_wr_ops)) - netfs_rreq_unmark_after_write(rreq); + netfs_rreq_unmark_after_write(rreq, false); } static void netfs_rreq_write_to_cache_work(struct work_struct *work) @@ -351,9 +359,10 @@ static void netfs_rreq_write_to_cache_work(struct work_struct *work) netfs_rreq_do_write_to_cache(rreq); } -static void netfs_rreq_write_to_cache(struct netfs_read_request *rreq) +static void netfs_rreq_write_to_cache(struct netfs_read_request *rreq, + bool was_async) { - if (in_softirq()) { + if (was_async) { rreq->work.func = netfs_rreq_write_to_cache_work; if (!queue_work(system_unbound_wq, &rreq->work)) BUG(); @@ -479,7 +488,7 @@ static bool netfs_rreq_perform_resubmissions(struct netfs_read_request *rreq) { struct netfs_read_subrequest *subreq; - WARN_ON(in_softirq()); + WARN_ON(in_interrupt()); trace_netfs_rreq(rreq, netfs_rreq_trace_resubmit); @@ -538,7 +547,7 @@ static void netfs_rreq_is_still_valid(struct netfs_read_request *rreq) * Note that we could be in an ordinary kernel thread, on a workqueue or in * softirq context at this point. We inherit a ref from the caller. */ -static void netfs_rreq_assess(struct netfs_read_request *rreq) +static void netfs_rreq_assess(struct netfs_read_request *rreq, bool was_async) { trace_netfs_rreq(rreq, netfs_rreq_trace_assess); @@ -558,30 +567,31 @@ static void netfs_rreq_assess(struct netfs_read_request *rreq) wake_up_bit(&rreq->flags, NETFS_RREQ_IN_PROGRESS); if (test_bit(NETFS_RREQ_WRITE_TO_CACHE, &rreq->flags)) - return netfs_rreq_write_to_cache(rreq); + return netfs_rreq_write_to_cache(rreq, was_async); - netfs_rreq_completed(rreq); + netfs_rreq_completed(rreq, was_async); } static void netfs_rreq_work(struct work_struct *work) { struct netfs_read_request *rreq = container_of(work, struct netfs_read_request, work); - netfs_rreq_assess(rreq); + netfs_rreq_assess(rreq, false); } /* * Handle the completion of all outstanding I/O operations on a read request. * We inherit a ref from the caller. */ -static void netfs_rreq_terminated(struct netfs_read_request *rreq) +static void netfs_rreq_terminated(struct netfs_read_request *rreq, + bool was_async) { if (test_bit(NETFS_RREQ_INCOMPLETE_IO, &rreq->flags) && - in_softirq()) { + was_async) { if (!queue_work(system_unbound_wq, &rreq->work)) BUG(); } else { - netfs_rreq_assess(rreq); + netfs_rreq_assess(rreq, was_async); } } @@ -589,6 +599,7 @@ static void netfs_rreq_terminated(struct netfs_read_request *rreq) * netfs_subreq_terminated - Note the termination of an I/O operation. * @subreq: The I/O request that has terminated. * @transferred_or_error: The amount of data transferred or an error code. + * @was_async: The termination was asynchronous * * This tells the read helper that a contributory I/O operation has terminated, * one way or another, and that it should integrate the results. @@ -599,11 +610,12 @@ static void netfs_rreq_terminated(struct netfs_read_request *rreq) * error code. The helper will look after reissuing I/O operations as * appropriate and writing downloaded data to the cache. * - * This may be called from a softirq handler, so we want to avoid taking the - * spinlock if we can. + * If @was_async is true, the caller might be running in softirq or interrupt + * context and we can't sleep. */ void netfs_subreq_terminated(struct netfs_read_subrequest *subreq, - ssize_t transferred_or_error) + ssize_t transferred_or_error, + bool was_async) { struct netfs_read_request *rreq = subreq->rreq; int u; @@ -647,11 +659,11 @@ void netfs_subreq_terminated(struct netfs_read_subrequest *subreq, /* If we decrement nr_rd_ops to 0, the ref belongs to us. */ u = atomic_dec_return(&rreq->nr_rd_ops); if (u == 0) - netfs_rreq_terminated(rreq); + netfs_rreq_terminated(rreq, was_async); else if (u == 1) wake_up_var(&rreq->nr_rd_ops); - netfs_put_subrequest(subreq); + netfs_put_subrequest(subreq, was_async); return; incomplete: @@ -796,7 +808,7 @@ static bool netfs_rreq_submit_slice(struct netfs_read_request *rreq, subreq_failed: rreq->error = subreq->error; - netfs_put_subrequest(subreq); + netfs_put_subrequest(subreq, false); return false; } @@ -901,7 +913,7 @@ void netfs_readahead(struct readahead_control *ractl, } while (rreq->submitted < rreq->len); if (rreq->submitted == 0) { - netfs_put_read_request(rreq); + netfs_put_read_request(rreq, false); return; } @@ -913,11 +925,11 @@ void netfs_readahead(struct readahead_control *ractl, /* If we decrement nr_rd_ops to 0, the ref belongs to us. */ if (atomic_dec_and_test(&rreq->nr_rd_ops)) - netfs_rreq_assess(rreq); + netfs_rreq_assess(rreq, false); return; cleanup_free: - netfs_put_read_request(rreq); + netfs_put_read_request(rreq, false); return; cleanup: if (netfs_priv) @@ -991,14 +1003,14 @@ int netfs_readpage(struct file *file, */ do { wait_var_event(&rreq->nr_rd_ops, atomic_read(&rreq->nr_rd_ops) == 1); - netfs_rreq_assess(rreq); + netfs_rreq_assess(rreq, false); } while (test_bit(NETFS_RREQ_IN_PROGRESS, &rreq->flags)); ret = rreq->error; if (ret == 0 && rreq->submitted < rreq->len) ret = -EIO; out: - netfs_put_read_request(rreq); + netfs_put_read_request(rreq, false); return ret; } EXPORT_SYMBOL(netfs_readpage); @@ -1136,7 +1148,7 @@ int netfs_write_begin(struct file *file, struct address_space *mapping, */ for (;;) { wait_var_event(&rreq->nr_rd_ops, atomic_read(&rreq->nr_rd_ops) == 1); - netfs_rreq_assess(rreq); + netfs_rreq_assess(rreq, false); if (!test_bit(NETFS_RREQ_IN_PROGRESS, &rreq->flags)) break; cond_resched(); @@ -1145,7 +1157,7 @@ int netfs_write_begin(struct file *file, struct address_space *mapping, ret = rreq->error; if (ret == 0 && rreq->submitted < rreq->len) ret = -EIO; - netfs_put_read_request(rreq); + netfs_put_read_request(rreq, false); if (ret < 0) goto error; diff --git a/include/linux/netfs.h b/include/linux/netfs.h index b2589b39feb8..c22b64db237d 100644 --- a/include/linux/netfs.h +++ b/include/linux/netfs.h @@ -60,7 +60,8 @@ enum netfs_read_source { NETFS_INVALID_READ, } __mode(byte); -typedef void (*netfs_io_terminated_t)(void *priv, ssize_t transferred_or_error); +typedef void (*netfs_io_terminated_t)(void *priv, ssize_t transferred_or_error, + bool was_async); /* * Resources required to do operations on a cache. @@ -189,7 +190,7 @@ extern int netfs_write_begin(struct file *, struct address_space *, const struct netfs_read_request_ops *, void *); -extern void netfs_subreq_terminated(struct netfs_read_subrequest *, ssize_t); +extern void netfs_subreq_terminated(struct netfs_read_subrequest *, ssize_t, bool); extern void netfs_stats_show(struct seq_file *); #endif /* _LINUX_NETFS_H */