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Wed, 10 Jul 2019 20:19:47 +0000 (UTC) Received: from dresden.str.redhat.com (unknown [10.40.205.108]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 0C47860BFC; Wed, 10 Jul 2019 20:19:42 +0000 (UTC) To: John Snow , qemu-block@nongnu.org, qemu-devel@nongnu.org References: <20190710010556.32365-1-jsnow@redhat.com> <20190710010556.32365-5-jsnow@redhat.com> <0f0c6f6e-501a-d747-13ff-edc45ccc231d@redhat.com> <4bc49e42-2dfa-8ca9-2cb6-678962f75f0a@redhat.com> From: Max Reitz Openpgp: preference=signencrypt Autocrypt: addr=mreitz@redhat.com; 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: <837ad3c2-efe7-5937-d9ba-c1084f2c7a17@redhat.com> Date: Wed, 10 Jul 2019 22:19:41 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.0 MIME-Version: 1.0 In-Reply-To: <4bc49e42-2dfa-8ca9-2cb6-678962f75f0a@redhat.com> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="fQNT5iv1OAQGGTb3oJ32D2qkFy1jt71Ws" X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Wed, 10 Jul 2019 20:19:47 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: Re: [Qemu-devel] [PATCH 4/8] block/backup: hoist bitmap check into QMP interface 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: Kevin Wolf , Markus Armbruster 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) --fQNT5iv1OAQGGTb3oJ32D2qkFy1jt71Ws Content-Type: multipart/mixed; boundary="zyRNDII5gOIgeLqWEbhJuFlIJHy9si8yj"; protected-headers="v1" From: Max Reitz To: John Snow , qemu-block@nongnu.org, qemu-devel@nongnu.org Cc: Markus Armbruster , Kevin Wolf , Eric Blake Message-ID: <837ad3c2-efe7-5937-d9ba-c1084f2c7a17@redhat.com> Subject: Re: [PATCH 4/8] block/backup: hoist bitmap check into QMP interface References: <20190710010556.32365-1-jsnow@redhat.com> <20190710010556.32365-5-jsnow@redhat.com> <0f0c6f6e-501a-d747-13ff-edc45ccc231d@redhat.com> <4bc49e42-2dfa-8ca9-2cb6-678962f75f0a@redhat.com> In-Reply-To: <4bc49e42-2dfa-8ca9-2cb6-678962f75f0a@redhat.com> --zyRNDII5gOIgeLqWEbhJuFlIJHy9si8yj Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable On 10.07.19 19:57, John Snow wrote: >=20 >=20 > On 7/10/19 12:11 PM, Max Reitz wrote: >> On 10.07.19 03:05, John Snow wrote: >>> This is nicer to do in the unified QMP interface that we have now, >>> because it lets us use the right terminology back at the user. >>> >>> Signed-off-by: John Snow >>> --- >>> block/backup.c | 13 ++++--------- >>> blockdev.c | 10 ++++++++++ >>> 2 files changed, 14 insertions(+), 9 deletions(-) >>> >>> diff --git a/block/backup.c b/block/backup.c >>> index e2729cf6fa..a64b768e24 100644 >>> --- a/block/backup.c >>> +++ b/block/backup.c >>> @@ -566,6 +566,10 @@ BlockJob *backup_job_create(const char *job_id, = BlockDriverState *bs, >>> assert(bs); >>> assert(target); >>> =20 >>> + /* QMP interface protects us from these cases */ >>> + assert(sync_mode !=3D MIRROR_SYNC_MODE_INCREMENTAL); >>> + assert(sync_bitmap || sync_mode !=3D MIRROR_SYNC_MODE_BITMAP); >> >> Implication would be a nice operator sometimes. >> >> ("assert(sync_mode =3D=3D MIRROR_SYNC_MODE_BITMAP -> sync_bitmap)") >> >> (Can you do that in C++? No, you can=E2=80=99t overload bool=E2=80=99= s operators, right?) >> >> Reviewed-by: Max Reitz >> >=20 > Yes, I also find this assertion kind of hard to read personally, but it= > feels somewhat clunky to write: >=20 > if (antecedent) { > assert(condition); > } >=20 > I suppose we can also phrase this as: >=20 > assert(sync_mode =3D=3D MIRROR_SYNC_MODE_BITMAP ? sync_bitmap : true); >=20 > Which might honestly be pretty good. Mind if I change it to this? Looks weird (mostly unfamiliar), but I do not. Max --zyRNDII5gOIgeLqWEbhJuFlIJHy9si8yj-- --fQNT5iv1OAQGGTb3oJ32D2qkFy1jt71Ws Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEkb62CjDbPohX0Rgp9AfbAGHVz0AFAl0mSF0ACgkQ9AfbAGHV z0BggQgAjBDDj+yiV0EGXvX0W7Bvmw/Z79ZWAhs/r+IdIpj8U6yT3Tyk+qRrsdSa VnpTpb+CGccIxfzBp5NXADhUnAgt5CAcw8gjAU2Y5DDkij7jLBVE0Gh3wLbHAHhy tdyegrJEghu1PwswEaJTOiui2rdwqCIa1b2QNikTDKb3R5vdMbNADHPr9SaOBTTC 6aNNwdflIY8IQE2uuYJiy6+CqzTz3c3LPVsYoygT+3fwy5sUMOwCDFGboMGcX/tx BvmT4IvhgEoa8DtS1HAwh24EI0OY46uvR2FCTrAYdUqOT9SobJqAVp+X3rogY3D7 x7xbmcwg3GGD2WwZmVZLOZ2oco3P/A== =DiEW -----END PGP SIGNATURE----- --fQNT5iv1OAQGGTb3oJ32D2qkFy1jt71Ws--