From patchwork Wed Aug 14 02:06:42 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yunke Cao X-Patchwork-Id: 13762740 Received: from mail-pj1-f47.google.com (mail-pj1-f47.google.com [209.85.216.47]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8CA8F1C694 for ; Wed, 14 Aug 2024 02:06:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.47 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723601220; cv=none; b=Jw1Q0f/AaSvDzkGaH8KvDH41a3aumbxbCisLZP6Bt8AgVNlTsqRLGOG2rPKoHDfVuNzBSP+qsas4vUKxs9Q/pHC+IXeQdbWprnBq00ghl2HwyCG9jTOW47AEOvtgxtLetXIBeTq6FK4nv4ooRKMfxHG+eZdm6I70nppcdSKfHMo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723601220; c=relaxed/simple; bh=8kDhKi1RqGp+MT7W/FRCaDuugxh1wL7FBntj3egggRk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=VMNXk0TBGvUke0Hog3oTbDlS14BuZcCrJwkBdazzH88pl1ZZce1igJodVRc7XfcC4WV+sg+xe4+sMqZO7yp50IF3n+rrzh2NGIfLMFfFzKQJUR+FE2d5GkhwDc+tbgaSBujGk3AJd/8zHwhl2fJ+H6kvAY7DRwDv1OSLwRWjIKY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org; spf=pass smtp.mailfrom=chromium.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b=JKd/Yk3m; arc=none smtp.client-ip=209.85.216.47 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=chromium.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="JKd/Yk3m" Received: by mail-pj1-f47.google.com with SMTP id 98e67ed59e1d1-2d1daa2577bso3800483a91.2 for ; Tue, 13 Aug 2024 19:06:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1723601219; x=1724206019; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=Py3r/mWLV/egkP5BiPd7Tab/P3CsruVhWzLlB8uYSYU=; b=JKd/Yk3mIe7gzCHbnY2LREpXdPRXsHhwRbSdK4aX3Cesg3E0YYjnWTuKV8aYyL1UJt uAS1LcIoee4+7IjT93fCtZRWzT/83zk3qEnUBzgyFKKyW5ZcW6xDA7xwCYOhVPrHzICN HM4JNL1x7is9kwKucBK1t8lV8HWnfUc6Zmqu0= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1723601219; x=1724206019; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=Py3r/mWLV/egkP5BiPd7Tab/P3CsruVhWzLlB8uYSYU=; b=kvggjcnAn+3S+CgnYB1o7ux92xHYVumijPD/r8BT0xPXNkAL3N5MnK9adcMCelMEXc FoZY+lI3SlC44E+yDkQY444DH467Ezl0A2dwycqWiRvivGAlYq34IM55SNIajauSXSq2 mNJg/4y+OPHNykjoI2DHEUQCIS7rsnst3vzaS1dBJ06iJAQ11tqzSkCXFA+8L8v07tfJ LSHc7kDWvwJqk3EUgAp/90kh96ezfPPW+5u70Yp/1EY6VZsnuyhQtny3hMmHEkDId1+S yP7H573d6FwjM2G/kz0+88dJsdiaBpURPhKfka/pUwYZCdjdsn/x4nQF0sbE3nSQY3tL pAsQ== X-Gm-Message-State: AOJu0YwVPu/iXF0pIk1OC84iQtQr3o6bNfOo082iRYBVd24GvWs4xCf7 tdjulX6ZFEXGHBGnyzaf8+5JaYLDsMbogDmVpzcKupammm8Wy0Q4vZP1FmmczA== X-Google-Smtp-Source: AGHT+IE8DMrWJ6UVX8hj0o/EARX1VUwjdml2R+xMPBDr7mac8mLpCY3xkKsiXGJJ0er6UONr5aA3kQ== X-Received: by 2002:a17:90b:3b87:b0:2c9:65df:f871 with SMTP id 98e67ed59e1d1-2d3aaa99367mr1448039a91.15.1723601218799; Tue, 13 Aug 2024 19:06:58 -0700 (PDT) Received: from yunkec1.tok.corp.google.com ([2401:fa00:8f:203:269a:7c5:e4f2:518c]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-2d3ac7d65b1sm303064a91.4.2024.08.13.19.06.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 13 Aug 2024 19:06:58 -0700 (PDT) From: Yunke Cao To: Tomasz Figa , Marek Szyprowski , Mauro Carvalho Chehab , Hans Verkuil Cc: linux-media@vger.kernel.org, Yunke Cao Subject: [PATCH v5 3/4] media: videobuf2-core: reverse the iteration order in __vb2_buf_dmabuf_put Date: Wed, 14 Aug 2024 11:06:42 +0900 Message-ID: <20240814020643.2229637-4-yunkec@chromium.org> X-Mailer: git-send-email 2.46.0.184.g6999bdac58-goog In-Reply-To: <20240814020643.2229637-1-yunkec@chromium.org> References: <20240814020643.2229637-1-yunkec@chromium.org> Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 This patch prepares for allowing multiple planes to share the same DMA buffer attachment. Release the planes from num_planes - 1 to 0 so that we don't leave invalid mem_priv pointers behind. Signed-off-by: Yunke Cao Acked-by: Tomasz Figa --- v5: - Add comment to explain why. - Update commit message to explain why. v3: - Change local variable to an integer to make the code cleaner. --- drivers/media/common/videobuf2/videobuf2-core.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c index b53d94659e30..e6af963307e3 100644 --- a/drivers/media/common/videobuf2/videobuf2-core.c +++ b/drivers/media/common/videobuf2/videobuf2-core.c @@ -323,9 +323,15 @@ static void __vb2_plane_dmabuf_put(struct vb2_buffer *vb, struct vb2_plane *p) */ static void __vb2_buf_dmabuf_put(struct vb2_buffer *vb) { - unsigned int plane; + int plane; - for (plane = 0; plane < vb->num_planes; ++plane) + /* + * When multiple planes share the same DMA buffer attachment, the plane + * with the lowest index owns the mem_priv. + * Put planes in the reversed order so that we don't leave invalid + * mem_priv behind. + */ + for (plane = vb->num_planes - 1; plane >= 0; --plane) __vb2_plane_dmabuf_put(vb, &vb->planes[plane]); }