From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 64768C4338F for ; Tue, 17 Aug 2021 13:11:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 42E33600D3 for ; Tue, 17 Aug 2021 13:11:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237125AbhHQNLc (ORCPT ); Tue, 17 Aug 2021 09:11:32 -0400 Received: from new2-smtp.messagingengine.com ([66.111.4.224]:53551 "EHLO new2-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235463AbhHQNLc (ORCPT ); Tue, 17 Aug 2021 09:11:32 -0400 Received: from compute2.internal (compute2.nyi.internal [10.202.2.42]) by mailnew.nyi.internal (Postfix) with ESMTP id 444E1580B2A; Tue, 17 Aug 2021 09:10:54 -0400 (EDT) Received: from mailfrontend2 ([10.202.2.163]) by compute2.internal (MEProxy); Tue, 17 Aug 2021 09:10:54 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kroah.com; h= date:from:to:cc:subject:message-id:references:mime-version :content-type:in-reply-to; s=fm1; bh=xtNL7MKvR9ER8Xw7XRE1SJsC55Q OmDv7otUyicJm4bA=; b=zer8n5c3j65hjKCHqkCGfl7KA/KMsl5U8k7Gkzel8tR TB9PI4MLkW/CsWyttCV718/Ezeg2KfSbE33Bmy+N03zQwuYViIzqWajW6HhFYAMB T41t+W4D8rMMtfjW2XkfwJ8zNCeTUZ6mFAOzGABBfEignNnGKN/QHd6u2L6yxgjg +ehHVphHjSSTCzdhTGiOhB9cB2xq/fqCtvTc6wacj2OA5IiF1YgwFDicoutu3irW jgZJU1oVUqY0X49hcNkqyGadiWyt+WtFQxe2gNEeLNB1wPMnKO2/2Kgu0KYOs4ya 86F69zuBMaulEEvZVL1RPQ3Y66VyW/AWB4/8UdKN7Jg== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to:x-me-proxy :x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm3; bh=xtNL7M KvR9ER8Xw7XRE1SJsC55QOmDv7otUyicJm4bA=; b=IU/RH3WYRX9P+Jn+dkkuT7 EnXAX2O/xHkvrYUHdZz98lZlo0GdmrLa5HFuXS1UEUgK9+iGc5vlzJKfh0ExfE10 kEgU+s9elo8x/Glle06gMwI4/EYiclv5hbLPNV7wpWR81lO2xGXHA1QFR5LJpK7j 83GTufZQ01ZoL6624wL7nl4fksfoL0otcGbCkkrYz6aWpeAH/TNhU/v1IY7/l+ff pdu/a20hpeZFkbrXzl9djWdO/DSfvor6FgTJH2BzAYJfY1iA/pzRJ1dfjfxVxTu+ 0hY1VlH4kLev0OveuoxsSYdvCHMWET2WJ/4amZ+FHAq5ZYxU230ST7MoOvmVE8nQ == X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvtddrleefgdeivdcutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenuc fjughrpeffhffvuffkfhggtggujgesthdtredttddtvdenucfhrhhomhepifhrvghgucfm jfcuoehgrhgvgheskhhrohgrhhdrtghomheqnecuggftrfgrthhtvghrnhepveeuheejgf ffgfeivddukedvkedtleelleeghfeljeeiueeggeevueduudekvdetnecuvehluhhsthgv rhfuihiivgeptdenucfrrghrrghmpehmrghilhhfrhhomhepghhrvghgsehkrhhorghhrd gtohhm X-ME-Proxy: Received: by mail.messagingengine.com (Postfix) with ESMTPA; Tue, 17 Aug 2021 09:10:50 -0400 (EDT) Date: Tue, 17 Aug 2021 15:10:48 +0200 From: Greg KH To: SelvaKumar S Cc: linux-nvme@lists.infradead.org, linux-block@vger.kernel.org, linux-api@vger.kernel.org, linux-scsi@vger.kernel.org, linux-fsdevel@vger.kernel.org, dm-devel@redhat.com, kbusch@kernel.org, axboe@kernel.dk, damien.lemoal@wdc.com, asml.silence@gmail.com, johannes.thumshirn@wdc.com, hch@lst.de, willy@infradead.org, kch@kernel.org, martin.petersen@oracle.com, mpatocka@redhat.com, bvanassche@acm.org, djwong@kernel.org, snitzer@redhat.com, agk@redhat.com, selvajove@gmail.com, joshiiitr@gmail.com, nj.shetty@samsung.com, nitheshshetty@gmail.com, joshi.k@samsung.com, javier.gonz@samsung.com Subject: Re: [PATCH 4/7] block: Introduce a new ioctl for simple copy Message-ID: References: <20210817101423.12367-1-selvakuma.s1@samsung.com> <20210817101423.12367-5-selvakuma.s1@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210817101423.12367-5-selvakuma.s1@samsung.com> Precedence: bulk List-ID: X-Mailing-List: linux-api@vger.kernel.org On Tue, Aug 17, 2021 at 03:44:20PM +0530, SelvaKumar S wrote: > From: Nitesh Shetty > > Add new BLKCOPY ioctl that offloads copying of one or more sources ranges > to a destination in the device. COPY ioctl accepts a 'copy_range' > structure that contains destination (in sectors), no of sources and > pointer to the array of source ranges. Each source range is represented by > 'range_entry' that contains start and length of source ranges (in sectors) > > MAX_COPY_NR_RANGE, limits the number of entries for the IOCTL and > MAX_COPY_TOTAL_LENGTH limits the total copy length, IOCTL can handle. > > Example code, to issue BLKCOPY: > /* Sample example to copy three source-ranges [0, 8] [16, 8] [32,8] to > * [64,24], on the same device */ > > int main(void) > { > int ret, fd; > struct range_entry source_range[] = {{.src = 0, .len = 8}, > {.src = 16, .len = 8}, {.src = 32, .len = 8},}; > struct copy_range cr; > > cr.dest = 64; > cr.nr_range = 3; > cr.range_list = (__u64)&source_range; > > fd = open("/dev/nvme0n1", O_RDWR); > if (fd < 0) return 1; > > ret = ioctl(fd, BLKCOPY, &cr); > if (ret < 0) printf("copy failure\n"); > > close(fd); > > return ret; > } > > Signed-off-by: Nitesh Shetty > Signed-off-by: SelvaKumar S > Signed-off-by: Kanchan Joshi > --- > block/ioctl.c | 33 +++++++++++++++++++++++++++++++++ > include/uapi/linux/fs.h | 8 ++++++++ > 2 files changed, 41 insertions(+) > > diff --git a/block/ioctl.c b/block/ioctl.c > index eb0491e90b9a..2af56d01e9fe 100644 > --- a/block/ioctl.c > +++ b/block/ioctl.c > @@ -143,6 +143,37 @@ static int blk_ioctl_discard(struct block_device *bdev, fmode_t mode, > GFP_KERNEL, flags); > } > > +static int blk_ioctl_copy(struct block_device *bdev, fmode_t mode, > + unsigned long arg) > +{ > + struct copy_range crange; > + struct range_entry *rlist; > + int ret; > + > + if (!(mode & FMODE_WRITE)) > + return -EBADF; > + > + if (copy_from_user(&crange, (void __user *)arg, sizeof(crange))) > + return -EFAULT; > + > + rlist = kmalloc_array(crange.nr_range, sizeof(*rlist), > + GFP_KERNEL); No error checking for huge values of nr_range? Is that wise? You really want userspace to be able to allocate "all" of the kernel memory in the system? thanks, greg k-h