From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 65CAF1C36 for ; Fri, 18 Jul 2025 16:27:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752856032; cv=none; b=UDTUVkd8hThawKXIaUSIxuCqOX/PmGYbHTg6O170QuEydJamZhxILY3ecxFPei0JjOjEzyxGhtcZJvLeVHZVRMn6C65OUxTsE/+stkXcuVxmt6fHs5eEHAuGV9oRYtG7qHtMoVdznYTnqR4SOeHB7K3Ao2pZivZzjwY5Xk76jPg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752856032; c=relaxed/simple; bh=dfaZmKtMzf4+/69pD9GvtqKvWVanAuCwdhVESh+FE4s=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=dwu/d4UZCHOQA9UW3KbBekKQVjwCeUZoXUPzNDNd2UdtIbJUefvYMif66k8yqI9/yNpXNBPjWvBwTtNQkV8mo7uI5064VGvuhij9dJTOOaJp8Vodk0rIoYMF7mmerQ55f+ov0M9m4Qrf3EAirk7eyad787NaKAQQItSdjc0Ra+Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=QghpmAf5; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="QghpmAf5" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0611EC4CEEB; Fri, 18 Jul 2025 16:27:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1752856031; bh=dfaZmKtMzf4+/69pD9GvtqKvWVanAuCwdhVESh+FE4s=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=QghpmAf5DaX18tsDbyEa/LAleza3kVED3U335qLCf6vB6qhxoRc8PISyayKSCLl0+ Ir0+2g2tP3NeobCRceeaW1vVsnnVqmNpqZ+3ZYqEMWVEyahwrzH6UV83JIjjVZadA1 fvGhGuemJOOApymaMA5946B9kOAu+yQUhUg4VL4rfyaZjuD/gTvTOBYYFnc6cd0y+4 BP/smWU+ptiGKkfZJbQlhf2Y1yK/1ENRW+lniOhYP/gQwJvhDEQnN7Rbi8An5ijrIK QOBGSucC0Gt3gmSlJTwuUO0g26r+2phVdMEb6niDxLMDFSssQpYJ2cZpP5hLPpv6d5 gE0gOmRP1BUsA== Date: Fri, 18 Jul 2025 09:27:10 -0700 From: "Darrick J. Wong" To: Amir Goldstein Cc: bschubert@ddn.com, John@groves.net, joannelkoong@gmail.com, linux-fsdevel@vger.kernel.org, bernd@bsbernd.com, neal@gompa.dev, miklos@szeredi.hu Subject: Re: [PATCH 3/4] libfuse: add statx support to the lower level library Message-ID: <20250718162710.GU2672029@frogsfrogsfrogs> References: <175279460363.714831.9608375779453686904.stgit@frogsfrogsfrogs> <175279460430.714831.6251867847811735740.stgit@frogsfrogsfrogs> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Fri, Jul 18, 2025 at 03:28:25PM +0200, Amir Goldstein wrote: > On Fri, Jul 18, 2025 at 1:39 AM Darrick J. Wong wrote: > > > > From: Darrick J. Wong > > > > Add statx support to the lower level fuse library. > > This looked familiar. > Merged 3 days ago: > https://github.com/libfuse/libfuse/pull/1026 > > > > > Signed-off-by: "Darrick J. Wong" > > --- > > include/fuse_lowlevel.h | 37 ++++++++++++++++++ > > lib/fuse_lowlevel.c | 97 +++++++++++++++++++++++++++++++++++++++++++++++ > > lib/fuse_versionscript | 2 + > > 3 files changed, 136 insertions(+) > > diff --git a/lib/fuse_lowlevel.c b/lib/fuse_lowlevel.c > > index ec30ebc4cdd074..8eeb6a8547da91 100644 > > --- a/lib/fuse_lowlevel.c > > +++ b/lib/fuse_lowlevel.c > > @@ -144,6 +144,43 @@ static void convert_attr(const struct fuse_setattr_in *attr, struct stat *stbuf) > > ST_CTIM_NSEC_SET(stbuf, attr->ctimensec); > > } > > > > +#ifdef STATX_BASIC_STATS > > +static int convert_statx(struct fuse_statx *stbuf, const struct statx *stx, > > + size_t size) > > +{ > > + if (sizeof(struct statx) != size) > > + return EOPNOTSUPP; > > + > > + stbuf->mask = stx->stx_mask & (STATX_BASIC_STATS | STATX_BTIME); > > + stbuf->blksize = stx->stx_blksize; > > + stbuf->attributes = stx->stx_attributes; > > + stbuf->nlink = stx->stx_nlink; > > + stbuf->uid = stx->stx_uid; > > + stbuf->gid = stx->stx_gid; > > + stbuf->mode = stx->stx_mode; > > + stbuf->ino = stx->stx_ino; > > + stbuf->size = stx->stx_size; > > + stbuf->blocks = stx->stx_blocks; > > + stbuf->attributes_mask = stx->stx_attributes_mask; > > + stbuf->rdev_major = stx->stx_rdev_major; > > + stbuf->rdev_minor = stx->stx_rdev_minor; > > + stbuf->dev_major = stx->stx_dev_major; > > + stbuf->dev_minor = stx->stx_dev_minor; > > + > > + stbuf->atime.tv_sec = stx->stx_atime.tv_sec; > > + stbuf->btime.tv_sec = stx->stx_btime.tv_sec; > > + stbuf->ctime.tv_sec = stx->stx_ctime.tv_sec; > > + stbuf->mtime.tv_sec = stx->stx_mtime.tv_sec; > > + > > + stbuf->atime.tv_nsec = stx->stx_atime.tv_nsec; > > + stbuf->btime.tv_nsec = stx->stx_btime.tv_nsec; > > + stbuf->ctime.tv_nsec = stx->stx_ctime.tv_nsec; > > + stbuf->mtime.tv_nsec = stx->stx_mtime.tv_nsec; > > + > > + return 0; > > +} > > +#endif > > + > > Why is this conversion not needed in the merged version? > What am I missing? The patch in upstream memcpy's struct statx to struct fuse_statx: memset(&arg, 0, sizeof(arg)); arg.flags = flags; arg.attr_valid = calc_timeout_sec(attr_timeout); arg.attr_valid_nsec = calc_timeout_nsec(attr_timeout); memcpy(&arg.stat, statx, sizeof(arg.stat)); As long as the fields in the two are kept exactly in sync, this isn't a problem and no explicit struct conversion is necessary. I also noticed that the !HAVE_STATX variant of _do_statx doesn't call fuse_reply_err(req, ENOSYS). I think that means a new kernel calling an old userspace would never receive a reply to a FUSE_STATX command and ... time out? My version also has explicit sizing of struct statx, but I concede that if that struct ever gets bigger we're going to have to rev the whole syscall anyway. I was being perhaps a bit paranoid. BTW, where are libfuse patches reviewed? I guess all the review are done via github PRs? --D > Thanks, > Amir. > > > static size_t iov_length(const struct iovec *iov, size_t count) > > { > > size_t seg; > > @@ -2653,6 +2690,64 @@ static void do_syncfs(fuse_req_t req, const fuse_ino_t nodeid, const void *inarg > > _do_syncfs(req, nodeid, inarg, NULL); > > } > > > > +#ifdef STATX_BASIC_STATS > > +int fuse_reply_statx(fuse_req_t req, const struct statx *statx, size_t size, > > + double attr_timeout) > > +{ > > + struct fuse_statx_out arg = { > > + .attr_valid = calc_timeout_sec(attr_timeout), > > + .attr_valid_nsec = calc_timeout_nsec(attr_timeout), > > + }; > > + > > + int err = convert_statx(&arg.stat, statx, size); > > + if (err) { > > + fuse_reply_err(req, err); > > + return err; > > + } > > + > > + return send_reply_ok(req, &arg, sizeof(arg)); > > +} > > + > > +static void _do_statx(fuse_req_t req, const fuse_ino_t nodeid, > > + const void *op_in, const void *in_payload) > > +{ > > + (void)in_payload; > > + const struct fuse_statx_in *arg = op_in; > > + struct fuse_file_info *fip = NULL; > > + struct fuse_file_info fi; > > + > > + if (arg->getattr_flags & FUSE_GETATTR_FH) { > > + memset(&fi, 0, sizeof(fi)); > > + fi.fh = arg->fh; > > + fip = &fi; > > + } > > + > > + if (req->se->op.statx) > > + req->se->op.statx(req, nodeid, arg->sx_flags, arg->sx_mask, > > + fip); > > + else > > + fuse_reply_err(req, ENOSYS); > > +} > > +#else > > +int fuse_reply_statx(fuse_req_t req, const struct statx *statx, > > + double attr_timeout) > > +{ > > + fuse_reply_err(req, ENOSYS); > > + return -ENOSYS; > > +} > > + > > +static void _do_statx(fuse_req_t req, const fuse_ino_t nodeid, > > + const void *op_in, const void *in_payload) > > +{ > > + fuse_reply_err(req, ENOSYS); > > +} > > +#endif /* STATX_BASIC_STATS */ > > + > > +static void do_statx(fuse_req_t req, const fuse_ino_t nodeid, const void *inarg) > > +{ > > + _do_statx(req, nodeid, inarg, NULL); > > +} > > + > > static bool want_flags_valid(uint64_t capable, uint64_t want) > > { > > uint64_t unknown_flags = want & (~capable); > > @@ -3627,6 +3722,7 @@ static struct { > > [FUSE_COPY_FILE_RANGE] = { do_copy_file_range, "COPY_FILE_RANGE" }, > > [FUSE_LSEEK] = { do_lseek, "LSEEK" }, > > [FUSE_SYNCFS] = { do_syncfs, "SYNCFS" }, > > + [FUSE_STATX] = { do_statx, "STATX" }, > > [FUSE_IOMAP_CONFIG]= { do_iomap_config, "IOMAP_CONFIG" }, > > [FUSE_IOMAP_BEGIN] = { do_iomap_begin, "IOMAP_BEGIN" }, > > [FUSE_IOMAP_END] = { do_iomap_end, "IOMAP_END" }, > > @@ -3686,6 +3782,7 @@ static struct { > > [FUSE_COPY_FILE_RANGE] = { _do_copy_file_range, "COPY_FILE_RANGE" }, > > [FUSE_LSEEK] = { _do_lseek, "LSEEK" }, > > [FUSE_SYNCFS] = { _do_syncfs, "SYNCFS" }, > > + [FUSE_STATX] = { _do_statx, "STATX" }, > > [FUSE_IOMAP_CONFIG] = { _do_iomap_config, "IOMAP_CONFIG" }, > > [FUSE_IOMAP_BEGIN] = { _do_iomap_begin, "IOMAP_BEGIN" }, > > [FUSE_IOMAP_END] = { _do_iomap_end, "IOMAP_END" }, > > diff --git a/lib/fuse_versionscript b/lib/fuse_versionscript > > index dc9fa2428b5325..a67b1802770335 100644 > > --- a/lib/fuse_versionscript > > +++ b/lib/fuse_versionscript > > @@ -223,6 +223,8 @@ FUSE_3.18 { > > fuse_reply_iomap_config; > > fuse_lowlevel_notify_iomap_upsert; > > fuse_lowlevel_notify_iomap_inval; > > + > > + fuse_reply_statx; > > } FUSE_3.17; > > > > # Local Variables: > > > > >