From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f52.google.com (mail-pj1-f52.google.com [209.85.216.52]) (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 47D9D2C9E for ; Fri, 7 Jan 2022 09:35:24 +0000 (UTC) Received: by mail-pj1-f52.google.com with SMTP id r16-20020a17090a0ad000b001b276aa3aabso11457022pje.0 for ; Fri, 07 Jan 2022 01:35:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=uPa2Y9r48Tr2TjgiZvIGBvNI/0pFs3VgGlpYuEIyE5A=; b=kyFrRWAXItsw/PhTpWsDKkqDCYcDPo/CSsPz1chXl/ng4d2iLDV1memUqL/OEl+92l jKGiMTZfVGLMq/WAxpbqkBA9h7hsvxOyy3iKpvjEEyM4xccxqp3tdTL9PIwyyUim/vQx bFvPiAgPzVA3vzOPwBiMo8GFUrN8g69RFQnTM= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=uPa2Y9r48Tr2TjgiZvIGBvNI/0pFs3VgGlpYuEIyE5A=; b=niLO6ARrzmdkHQ6I0Q5OooP/OFqaPYuxYA7dewpsXY6F4DSfUVvvbVQHWpyA8dYL/H TgCRC8CO6B/npH9hhpQBB42tUJwQ0c2TAtn4vYh4dhJpop5ppNA8P9tA9KtMtyBe8EXq N0LlzXJ8twQNTQrVKWsoKEHIm7m5Fxqetb4wNRFoUN51aTAKIzzM2u/ajkr9QNFYUz6r 4sRkWj33+4L1oAD7cs1k5QeVDbDYpsqam8/mcAjuZzNv9QJErb/XIVojwZOWjHWxynyB +aXaTN1KYU/l40lhe7Esfyk624rzcur9ivdOZ3FcQPIrcl9Mzh22wvIeCmBPqXe46Dld NlYQ== X-Gm-Message-State: AOAM533mEssIqskYs13AbGohZZ1kqNecWe7YyyZrAJFKDv295oGddv9k x8lZQ7jFeHZh0o4Hw4So71Kh+Q== X-Google-Smtp-Source: ABdhPJz1h5qNBJkMbnlr4tRBRegzKszr22xmYctO5J2KYeGk4idAT8zh0U05V3Xl73n4YwTJZIM3aA== X-Received: by 2002:a17:902:7c05:b0:149:a3b4:934c with SMTP id x5-20020a1709027c0500b00149a3b4934cmr35858061pll.42.1641548123889; Fri, 07 Jan 2022 01:35:23 -0800 (PST) Received: from wenstp920.tpe.corp.google.com ([2401:fa00:1:10:8f6b:ee:64d8:ae81]) by smtp.gmail.com with ESMTPSA id j17sm5269192pfu.77.2022.01.07.01.35.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 07 Jan 2022 01:35:23 -0800 (PST) From: Chen-Yu Tsai To: Ezequiel Garcia , Philipp Zabel , Mauro Carvalho Chehab , Hans Verkuil , Greg Kroah-Hartman Cc: Chen-Yu Tsai , linux-media@vger.kernel.org, linux-rockchip@lists.infradead.org, linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org Subject: [PATCH RFT v2 8/8] media: hantro: jpeg: Remove open-coded size in quantization table code Date: Fri, 7 Jan 2022 17:34:55 +0800 Message-Id: <20220107093455.73766-9-wenst@chromium.org> X-Mailer: git-send-email 2.34.1.575.g55b058a8bb-goog In-Reply-To: <20220107093455.73766-1-wenst@chromium.org> References: <20220107093455.73766-1-wenst@chromium.org> Precedence: bulk X-Mailing-List: linux-staging@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit The quantization tables used in the Hantro JPEG encoder driver are implicitly sized by the data they contain, but the loop that scales the tables based on the compression quality hard codes the size to 64. No code exists to check whether the two actually match. Commit 85bdcb7eaae7 ("media: hantro: Write the quantization tables in proper order") introduced two new tables, with sizes hardcoded to 64, but still no checking if all the sizes are the same. Commit 41479adb5e52 ("media: hantro: Avoid global variable for jpeg quantization tables") added the macro JPEG_QUANT_SIZE, but only the newly added fields used this. This has resulted in code scattered with magic numbers and array sizes that happen to match up, without any sort of sanity checking to enforce it. Drop the hard-coded array sizes, replace the magic loop count with a proper JPEG_QUANT_SIZE macro, and add BUILD_BUG_ON()s to check that all the table sizes match up. Signed-off-by: Chen-Yu Tsai --- drivers/staging/media/hantro/hantro_jpeg.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/drivers/staging/media/hantro/hantro_jpeg.c b/drivers/staging/media/hantro/hantro_jpeg.c index 84d3f0bfff00..d07b1b449b61 100644 --- a/drivers/staging/media/hantro/hantro_jpeg.c +++ b/drivers/staging/media/hantro/hantro_jpeg.c @@ -49,7 +49,7 @@ static const unsigned char chroma_q_table[] = { 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63 }; -static const unsigned char zigzag[64] = { +static const unsigned char zigzag[] = { 0, 1, 8, 16, 9, 2, 3, 10, 17, 24, 32, 25, 18, 11, 4, 5, 12, 19, 26, 33, 40, 48, 41, 34, @@ -60,7 +60,7 @@ static const unsigned char zigzag[64] = { 53, 60, 61, 54, 47, 55, 62, 63 }; -static const u32 hw_reorder[64] = { +static const u32 hw_reorder[] = { 0, 8, 16, 24, 1, 9, 17, 25, 32, 40, 48, 56, 33, 41, 49, 57, 2, 10, 18, 26, 3, 11, 19, 27, @@ -292,7 +292,10 @@ jpeg_scale_quant_table(unsigned char *file_q_tab, { int i; - for (i = 0; i < 64; i++) { + BUILD_BUG_ON(ARRAY_SIZE(zigzag) != JPEG_QUANT_SIZE); + BUILD_BUG_ON(ARRAY_SIZE(hw_reorder) != JPEG_QUANT_SIZE); + + for (i = 0; i < JPEG_QUANT_SIZE; i++) { file_q_tab[i] = jpeg_scale_qp(tab[zigzag[i]], scale); reordered_q_tab[i] = jpeg_scale_qp(tab[hw_reorder[i]], scale); } @@ -311,6 +314,11 @@ static void jpeg_set_quality(struct hantro_jpeg_ctx *ctx) else scale = 200 - 2 * ctx->quality; + BUILD_BUG_ON(ARRAY_SIZE(luma_q_table) != JPEG_QUANT_SIZE); + BUILD_BUG_ON(ARRAY_SIZE(chroma_q_table) != JPEG_QUANT_SIZE); + BUILD_BUG_ON(ARRAY_SIZE(ctx->hw_luma_qtable) != JPEG_QUANT_SIZE); + BUILD_BUG_ON(ARRAY_SIZE(ctx->hw_chroma_qtable) != JPEG_QUANT_SIZE); + jpeg_scale_quant_table(ctx->buffer + LUMA_QUANT_OFF, ctx->hw_luma_qtable, luma_q_table, scale); jpeg_scale_quant_table(ctx->buffer + CHROMA_QUANT_OFF, -- 2.34.1.575.g55b058a8bb-goog