From mboxrd@z Thu Jan 1 00:00:00 1970 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=-15.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 09002C43460 for ; Tue, 27 Apr 2021 10:28:06 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5519B613E5 for ; Tue, 27 Apr 2021 10:28:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5519B613E5 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:58832 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lbKwm-0000r9-76 for qemu-devel@archiver.kernel.org; Tue, 27 Apr 2021 06:28:04 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:36494) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lbKtt-0008Ad-TJ for qemu-devel@nongnu.org; Tue, 27 Apr 2021 06:25:09 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:22827) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lbKtp-0003kL-N5 for qemu-devel@nongnu.org; Tue, 27 Apr 2021 06:25:05 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1619519100; 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: in-reply-to:in-reply-to:references:references; bh=ltPM7XxxSBxSKDRFyhmHsMKJYhXmBDDws/ZTXEQpWE0=; b=a4Rv1+HcY7gPsn7GeEdh4fQ/E8z+iuzG9JrPCRvfAwFj91aiA2imV5iCboa7OUI3LT9P47 MnzyVakIX4p14WZCoOMJtSP7tPU0rbnBleIqs1NM222MaOvcbhaLa9051vmcyhp89WMnG4 nDGh0xaa6NNs5L94J9fzNRbJXkiNK/k= 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-558-fxG39d3YMzu6U9s0c8HYVQ-1; Tue, 27 Apr 2021 06:24:58 -0400 X-MC-Unique: fxG39d3YMzu6U9s0c8HYVQ-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 E32F5A0CAE; Tue, 27 Apr 2021 10:24:57 +0000 (UTC) Received: from work-vm (ovpn-114-253.ams2.redhat.com [10.36.114.253]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 31C0360CC6; Tue, 27 Apr 2021 10:24:45 +0000 (UTC) Date: Tue, 27 Apr 2021 11:24:42 +0100 From: "Dr. David Alan Gilbert" To: Mahmoud Mandour Subject: Re: [PATCH v2 2/7] virtiofds: Changed allocations of iovec to GLib's functions Message-ID: References: <20210420154643.58439-1-ma.mandourr@gmail.com> <20210420154643.58439-3-ma.mandourr@gmail.com> MIME-Version: 1.0 In-Reply-To: <20210420154643.58439-3-ma.mandourr@gmail.com> User-Agent: Mutt/2.0.6 (2021-03-06) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dgilbert@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Received-SPF: pass client-ip=170.10.133.124; envelope-from=dgilbert@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -29 X-Spam_score: -3.0 X-Spam_bar: --- X-Spam_report: (-3.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.219, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "open list:virtiofs" , qemu-devel@nongnu.org, Stefan Hajnoczi Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" * Mahmoud Mandour (ma.mandourr@gmail.com) wrote: > Replaced the calls to malloc()/calloc() and their respective > calls to free() of iovec structs with GLib's allocation and > deallocation functions. > > Also, in one instance, used g_new0() instead of a calloc() call plus > a null-checking assertion. > > iovec structs were created locally and freed as the function > ends. Hence, I used g_autofree and removed the respective calls to > free(). > > In one instance, a struct fuse_ioctl_iovec pointer is returned from a > function, namely, fuse_ioctl_iovec_copy. There, I used g_steal_pointer() > in conjunction with g_autofree, this gives the ownership of the pointer > to the calling function and still auto-frees the memory when the calling > function finishes (maintaining the symantics of previous code). > > Signed-off-by: Mahmoud Mandour > Reviewed-by: Stefan Hajnoczi > --- > tools/virtiofsd/fuse_lowlevel.c | 19 +++++++------------ > tools/virtiofsd/fuse_virtio.c | 6 +----- > 2 files changed, 8 insertions(+), 17 deletions(-) > > diff --git a/tools/virtiofsd/fuse_lowlevel.c b/tools/virtiofsd/fuse_lowlevel.c > index 812cef6ef6..f965299ad9 100644 > --- a/tools/virtiofsd/fuse_lowlevel.c > +++ b/tools/virtiofsd/fuse_lowlevel.c > @@ -217,9 +217,9 @@ static int send_reply(fuse_req_t req, int error, const void *arg, > int fuse_reply_iov(fuse_req_t req, const struct iovec *iov, int count) > { > int res; > - struct iovec *padded_iov; > + g_autofree struct iovec *padded_iov; > > - padded_iov = malloc((count + 1) * sizeof(struct iovec)); > + padded_iov = g_try_new(struct iovec, count + 1); > if (padded_iov == NULL) { > return fuse_reply_err(req, ENOMEM); > } > @@ -228,7 +228,6 @@ int fuse_reply_iov(fuse_req_t req, const struct iovec *iov, int count) > count++; > > res = send_reply_iov(req, 0, padded_iov, count); > - free(padded_iov); > > return res; > } OK. > @@ -565,10 +564,10 @@ int fuse_reply_bmap(fuse_req_t req, uint64_t idx) > static struct fuse_ioctl_iovec *fuse_ioctl_iovec_copy(const struct iovec *iov, > size_t count) > { > - struct fuse_ioctl_iovec *fiov; > + g_autofree struct fuse_ioctl_iovec *fiov; > size_t i; > > - fiov = malloc(sizeof(fiov[0]) * count); > + fiov = g_try_new(fuse_ioctl_iovec, count); > if (!fiov) { > return NULL; > } > @@ -578,7 +577,7 @@ static struct fuse_ioctl_iovec *fuse_ioctl_iovec_copy(const struct iovec *iov, > fiov[i].len = iov[i].iov_len; > } > > - return fiov; > + return g_steal_pointer(&fiov); > } This is OK, but doesn't gain anything - marking it as g_autofree'ing and always stealing is no benefit. > > int fuse_reply_ioctl_retry(fuse_req_t req, const struct iovec *in_iov, > @@ -629,9 +628,6 @@ int fuse_reply_ioctl_retry(fuse_req_t req, const struct iovec *in_iov, > > res = send_reply_iov(req, 0, iov, count); > out: > - free(in_fiov); > - free(out_fiov); > - I don't think you can do that - I think you're relying here on the g_autofree from fuse_ioclt_iovec_copy - but my understanding is that doesn't work; g_autofree is scoped, so it's designed to free at the end of fuse_ioctl_iovec_copy, fuse_reply_ioctl_retry doesn't know that the ion_fiov were allocated that way, so it won't get autocleaned up. > return res; > > enomem: > @@ -663,11 +659,11 @@ int fuse_reply_ioctl(fuse_req_t req, int result, const void *buf, size_t size) > int fuse_reply_ioctl_iov(fuse_req_t req, int result, const struct iovec *iov, > int count) > { > - struct iovec *padded_iov; > + g_autofree struct iovec *padded_iov; > struct fuse_ioctl_out arg; > int res; > > - padded_iov = malloc((count + 2) * sizeof(struct iovec)); > + padded_iov = g_try_new(struct iovec, count + 2); > if (padded_iov == NULL) { > return fuse_reply_err(req, ENOMEM); > } > @@ -680,7 +676,6 @@ int fuse_reply_ioctl_iov(fuse_req_t req, int result, const struct iovec *iov, > memcpy(&padded_iov[2], iov, count * sizeof(struct iovec)); > > res = send_reply_iov(req, 0, padded_iov, count + 2); > - free(padded_iov); > > return res; > } OK > diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c > index 3e13997406..07e5d91a9f 100644 > --- a/tools/virtiofsd/fuse_virtio.c > +++ b/tools/virtiofsd/fuse_virtio.c > @@ -347,8 +347,7 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch, > * Build a copy of the the in_sg iov so we can skip bits in it, > * including changing the offsets > */ > - struct iovec *in_sg_cpy = calloc(sizeof(struct iovec), in_num); > - assert(in_sg_cpy); > + g_autofree struct iovec *in_sg_cpy = g_new0(struct iovec, in_num); > memcpy(in_sg_cpy, in_sg, sizeof(struct iovec) * in_num); > /* These get updated as we skip */ > struct iovec *in_sg_ptr = in_sg_cpy; > @@ -386,7 +385,6 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch, > ret = errno; > fuse_log(FUSE_LOG_DEBUG, "%s: preadv failed (%m) len=%zd\n", > __func__, len); > - free(in_sg_cpy); > goto err; > } > fuse_log(FUSE_LOG_DEBUG, "%s: preadv ret=%d len=%zd\n", __func__, > @@ -410,13 +408,11 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch, > if (ret != len) { > fuse_log(FUSE_LOG_DEBUG, "%s: ret!=len\n", __func__); > ret = EIO; > - free(in_sg_cpy); > goto err; > } > in_sg_left -= ret; > len -= ret; > } while (in_sg_left); > - free(in_sg_cpy); Yes, this is where the autofree really helps; getting rid of a few free's. Dave > /* Need to fix out->len on EOF */ > if (len) { > -- > 2.25.1 > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK