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prefer-encrypt=mutual; keydata= mQENBFXOJlcBCADEyyhOTsoa/2ujoTRAJj4MKA21dkxxELVj3cuILpLTmtachWj7QW+TVG8U /PsMCFbpwsQR7oEy8eHHZwuGQsNpEtNC2G/L8Yka0BIBzv7dEgrPzIu+W3anZXQW4702+uES U29G8TP/NGfXRRHGlbBIH9KNUnOSUD2vRtpOLXkWsV5CN6vQFYgQfFvmp5ZpPeUe6xNplu8V mcTw8OSEDW/ZnxJc8TekCKZSpdzYoxfzjm7xGmZqB18VFwgJZlIibt1HE0EB4w5GsD7x5ekh awIe3RwoZgZDLQMdOitJ1tUc8aqaxvgA4tz6J6st8D8pS//m1gAoYJWGwwIVj1DjTYLtABEB AAG0HU1heCBSZWl0eiA8bXJlaXR6QHJlZGhhdC5jb20+iQFTBBMBCAA9AhsDBQkSzAMABQsJ CAcCBhUICQoLAgQWAgMBAh4BAheABQJVzie5FRhoa3A6Ly9rZXlzLmdudXBnLm5ldAAKCRD0 B9sAYdXPQDcIB/9uNkbYEex1rHKz3mr12uxYMwLOOFY9fstP5aoVJQ1nWQVB6m2cfKGdcRe1 2/nFaHSNAzT0NnKz2MjhZVmcrpyd2Gp2QyISCfb1FbT82GMtXFj1wiHmPb3CixYmWGQUUh+I AvUqsevLA+WihgBUyaJq/vuDVM1/K9Un+w+Tz5vpeMidlIsTYhcsMhn0L9wlCjoucljvbDy/ 8C9L2DUdgi3XTa0ORKeflUhdL4gucWoAMrKX2nmPjBMKLgU7WLBc8AtV+84b9OWFML6NEyo4 4cP7cM/07VlJK53pqNg5cHtnWwjHcbpGkQvx6RUx6F1My3y52vM24rNUA3+ligVEgPYBuQEN BFXOJlcBCADAmcVUNTWT6yLWQHvxZ0o47KCP8OcLqD+67T0RCe6d0LP8GsWtrJdeDIQk+T+F xO7DolQPS6iQ6Ak2/lJaPX8L0BkEAiMuLCKFU6Bn3lFOkrQeKp3u05wCSV1iKnhg0UPji9V2 W5eNfy8F4ZQHpeGUGy+liGXlxqkeRVhLyevUqfU0WgNqAJpfhHSGpBgihUupmyUg7lfUPeRM DzAN1pIqoFuxnN+BRHdAecpsLcbR8sQddXmDg9BpSKozO/JyBmaS1RlquI8HERQoe6EynJhd 64aICHDfj61rp+/0jTIcevxIIAzW70IadoS/y3DVIkuhncgDBvGbF3aBtjrJVP+5ABEBAAGJ ASUEGAEIAA8FAlXOJlcCGwwFCRLMAwAACgkQ9AfbAGHVz0CbFwf9F/PXxQR9i4N0iipISYjU sxVdjJOM2TMut+ZZcQ6NSMvhZ0ogQxJ+iEQ5OjnIputKvPVd5U7WRh+4lF1lB/NQGrGZQ1ic alkj6ocscQyFwfib+xIe9w8TG1CVGkII7+TbS5pXHRxZH1niaRpoi/hYtgzkuOPp35jJyqT/ /ELbqQTDAWcqtJhzxKLE/ugcOMK520dJDeb6x2xVES+S5LXby0D4juZlvUj+1fwZu+7Io5+B bkhSVPb/QdOVTpnz7zWNyNw+OONo1aBUKkhq2UIByYXgORPFnbfMY7QWHcjpBVw9MgC4tGeF R4bv+1nAMMxKmb5VvQCExr0eFhJUAHAhVg== Message-ID: <256dd14e-f5c3-7f83-60e0-9bdacdcd5f99@redhat.com> Date: Thu, 15 Oct 2020 17:59:42 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.11.0 MIME-Version: 1.0 In-Reply-To: <20201015154123.GK4610@merkur.fritz.box> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=mreitz@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="dmDStrMlmfgGInukuXDnJuQBIu6G1TFLH" Received-SPF: pass client-ip=63.128.21.124; envelope-from=mreitz@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/10/15 02:10:02 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -30 X-Spam_score: -3.1 X-Spam_bar: --- X-Spam_report: (-3.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-1.019, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=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: Stefan Hajnoczi , qemu-devel@nongnu.org, qemu-block@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --dmDStrMlmfgGInukuXDnJuQBIu6G1TFLH Content-Type: multipart/mixed; boundary="gpfHs4WhK3wu2IpKSWUgF0E6kpw8SZj7V" --gpfHs4WhK3wu2IpKSWUgF0E6kpw8SZj7V Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable On 15.10.20 17:41, Kevin Wolf wrote: > Am 15.10.2020 um 16:46 hat Max Reitz geschrieben: >> On 15.10.20 10:57, Kevin Wolf wrote: >>> Am 22.09.2020 um 12:49 hat Max Reitz geschrieben: [...] >>>> +static void fuse_export_shutdown(BlockExport *blk_exp) >>>> +{ >>>> + FuseExport *exp =3D container_of(blk_exp, FuseExport, common); >>>> + >>>> + if (exp->fuse_session) { >>>> + fuse_session_exit(exp->fuse_session); >>>> + >>>> + if (exp->mounted) { >>>> + fuse_session_unmount(exp->fuse_session); >>>> + exp->mounted =3D false; >>>> + } >>>> + >>>> + if (exp->fd_handler_set_up) { >>>> + aio_set_fd_handler(exp->common.ctx, >>>> + fuse_session_fd(exp->fuse_session), tr= ue, >>>> + NULL, NULL, NULL, NULL); >>>> + exp->fd_handler_set_up =3D false; >>>> + } >>>> + >>>> + fuse_session_destroy(exp->fuse_session); >>>> + exp->fuse_session =3D NULL; >>> >>> What happens if a request is still in flight? >>> >>> Oh, can't happen because the driver is fully synchronous after this >>> series. Fair enough, making it asynchronous can come on top of it. >> >> (I had multiple approaches of handling parallel requests, but none made >> a substantial performance difference, which is why I left the driver in >> the most simple form for this first proposal.) >=20 > I think the more relevant part is that we'd block the guest or anything > else running in the main loop while doing I/O. >=20 > Not a problem if you spawn a new qemu-storage-daemon just for this FUSE > export, but if you want to have multiple exports, or export from the > system emulator, you probably don't want to have synchronous operations. Ah, hm. Hmm. O:) Does NBD work any different, though? I had always assumed it runs in the BB=E2=80=99s context. Max --gpfHs4WhK3wu2IpKSWUgF0E6kpw8SZj7V-- --dmDStrMlmfgGInukuXDnJuQBIu6G1TFLH Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEyBAEBCAAdFiEEkb62CjDbPohX0Rgp9AfbAGHVz0AFAl+Ice4ACgkQ9AfbAGHV z0A+wwf43I78j5ybMn2TXKqTXEqWyauplvYusid+vdtzNqov7rD1+IPNYfO6vB6A gTP0AnyzzZVUQXiqu5cW82y2EsAQwhsKIskmz7In2BePbQMfrCmdIbjUk8G52Pht KESpkuID3uVqCoFztpmB0U+mGeN5ULtkKZkfgIjtozpZ1q+EEPqTz4g5ZPphjWDA nQjkpFhKqihrcT+yq5YsMC0020eXv8Out7b2PlG+f/zSTHuB3fVUAUEBPTGv1u9V o1H1HdrSSckJqMxektvQ4rQrDc53R4AZ1HLFRL7ofoxO3dUa5JLCE1q/UFQhcy1q B9zEAkYpOWQ/vt4AhZ6/Mfq47qeL =TEOg -----END PGP SIGNATURE----- --dmDStrMlmfgGInukuXDnJuQBIu6G1TFLH--