From mboxrd@z Thu Jan 1 00:00:00 1970 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Subject: dmaengine: tegra-apb: Use struct_size() in devm_kzalloc() From: "Gustavo A. R. Silva" Message-Id: <20190104211612.GA14300@embeddedor> Date: Fri, 4 Jan 2019 15:16:12 -0600 To: Laxman Dewangan , Jon Hunter , Dan Williams , Vinod Koul , Thierry Reding Cc: dmaengine@vger.kernel.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" List-ID: T25lIG9mIHRoZSBtb3JlIGNvbW1vbiBjYXNlcyBvZiBhbGxvY2F0aW9uIHNpemUgY2FsY3VsYXRp b25zIGlzIGZpbmRpbmcKdGhlIHNpemUgb2YgYSBzdHJ1Y3R1cmUgdGhhdCBoYXMgYSB6ZXJvLXNp emVkIGFycmF5IGF0IHRoZSBlbmQsIGFsb25nCndpdGggbWVtb3J5IGZvciBzb21lIG51bWJlciBv ZiBlbGVtZW50cyBmb3IgdGhhdCBhcnJheS4gRm9yIGV4YW1wbGU6CgpzdHJ1Y3QgZm9vIHsKICAg IGludCBzdHVmZjsKICAgIHZvaWQgKmVudHJ5W107Cn07CgppbnN0YW5jZSA9IGRldm1fa3phbGxv YyhkZXYsIHNpemVvZihzdHJ1Y3QgZm9vKSArIHNpemVvZih2b2lkICopICogY291bnQsIEdGUF9L RVJORUwpOwoKSW5zdGVhZCBvZiBsZWF2aW5nIHRoZXNlIG9wZW4tY29kZWQgYW5kIHByb25lIHRv IHR5cGUgbWlzdGFrZXMsIHdlIGNhbgpub3cgdXNlIHRoZSBuZXcgc3RydWN0X3NpemUoKSBoZWxw ZXI6CgppbnN0YW5jZSA9IGRldm1fa3phbGxvYyhkZXYsIHN0cnVjdF9zaXplKGluc3RhbmNlLCBl bnRyeSwgY291bnQpLCBHRlBfS0VSTkVMKTsKClRoaXMgY29kZSB3YXMgZGV0ZWN0ZWQgd2l0aCB0 aGUgaGVscCBvZiBDb2NjaW5lbGxlLgoKU2lnbmVkLW9mZi1ieTogR3VzdGF2byBBLiBSLiBTaWx2 YSA8Z3VzdGF2b0BlbWJlZGRlZG9yLmNvbT4KLS0tCiBkcml2ZXJzL2RtYS90ZWdyYTIwLWFwYi1k bWEuYyB8IDUgKysrLS0KIDEgZmlsZSBjaGFuZ2VkLCAzIGluc2VydGlvbnMoKyksIDIgZGVsZXRp b25zKC0pCgpkaWZmIC0tZ2l0IGEvZHJpdmVycy9kbWEvdGVncmEyMC1hcGItZG1hLmMgYi9kcml2 ZXJzL2RtYS90ZWdyYTIwLWFwYi1kbWEuYwppbmRleCA5YTU1OGUzMGM0NjEuLjY5N2YzMTYwNTVj ZiAxMDA2NDQKLS0tIGEvZHJpdmVycy9kbWEvdGVncmEyMC1hcGItZG1hLmMKKysrIGIvZHJpdmVy cy9kbWEvdGVncmEyMC1hcGItZG1hLmMKQEAgLTEzMTksOCArMTMxOSw5IEBAIHN0YXRpYyBpbnQg dGVncmFfZG1hX3Byb2JlKHN0cnVjdCBwbGF0Zm9ybV9kZXZpY2UgKnBkZXYpCiAJCXJldHVybiAt RU5PREVWOwogCX0KIAotCXRkbWEgPSBkZXZtX2t6YWxsb2MoJnBkZXYtPmRldiwgc2l6ZW9mKCp0 ZG1hKSArIGNkYXRhLT5ucl9jaGFubmVscyAqCi0JCQlzaXplb2Yoc3RydWN0IHRlZ3JhX2RtYV9j aGFubmVsKSwgR0ZQX0tFUk5FTCk7CisJdGRtYSA9IGRldm1fa3phbGxvYygmcGRldi0+ZGV2LAor CQkJICAgIHN0cnVjdF9zaXplKHRkbWEsIGNoYW5uZWxzLCBjZGF0YS0+bnJfY2hhbm5lbHMpLAor CQkJICAgIEdGUF9LRVJORUwpOwogCWlmICghdGRtYSkKIAkJcmV0dXJuIC1FTk9NRU07CiAK From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Gustavo A. R. Silva" Subject: [PATCH] dmaengine: tegra-apb: Use struct_size() in devm_kzalloc() Date: Fri, 4 Jan 2019 15:16:12 -0600 Message-ID: <20190104211612.GA14300@embeddedor> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org To: Laxman Dewangan , Jon Hunter , Dan Williams , Vinod Koul , Thierry Reding Cc: dmaengine@vger.kernel.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" List-Id: linux-tegra@vger.kernel.org One of the more common cases of allocation size calculations is finding the size of a structure that has a zero-sized array at the end, along with memory for some number of elements for that array. For example: struct foo { int stuff; void *entry[]; }; instance = devm_kzalloc(dev, sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL); Instead of leaving these open-coded and prone to type mistakes, we can now use the new struct_size() helper: instance = devm_kzalloc(dev, struct_size(instance, entry, count), GFP_KERNEL); This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- drivers/dma/tegra20-apb-dma.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c index 9a558e30c461..697f316055cf 100644 --- a/drivers/dma/tegra20-apb-dma.c +++ b/drivers/dma/tegra20-apb-dma.c @@ -1319,8 +1319,9 @@ static int tegra_dma_probe(struct platform_device *pdev) return -ENODEV; } - tdma = devm_kzalloc(&pdev->dev, sizeof(*tdma) + cdata->nr_channels * - sizeof(struct tegra_dma_channel), GFP_KERNEL); + tdma = devm_kzalloc(&pdev->dev, + struct_size(tdma, channels, cdata->nr_channels), + GFP_KERNEL); if (!tdma) return -ENOMEM; -- 2.20.1