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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 4CAF9C46CA6 for ; Tue, 14 Nov 2023 23:17:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Mime-Version:References:In-Reply-To: Message-Id:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=SgQkU8AZvIUR9C7BCDBft+hps9BhXIuunEBD7qZUUNY=; b=xTqf4T/9Rd+GK8 Up6DmEeeQJitcFclwZFuyVN+JRNX4giW3UP2sV+5U7LS39O/s/l5A6jXlMlvHK6vyaOUnpLz2YvmN XynevkPnBHYH+3d++gcEz8PB/DEGcd0dVEN79WePKk5IP5UsqSejqovlhuVeMHRVQrrjtNmP92DY6 xAbEcB1nQx9KCneu7gPHAclZYuIBnEv4UIaON1tT+lCvRUfiOQ509XnUwTe0suU7FGNtVG7ipAtVK 2eTdC6laOUG22RG6IKBZjOiVrPjkN6nRTjj3AqLbVclSetiagJ+41nOa5rli3u6KHopXpSgwgDgON dO876VMhGSqgTlcxJz9w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1r32fK-00GxqD-0t; Tue, 14 Nov 2023 23:17:54 +0000 Received: from sin.source.kernel.org ([2604:1380:40e1:4800::1]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1r32fG-00GxpD-28; Tue, 14 Nov 2023 23:17:52 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sin.source.kernel.org (Postfix) with ESMTP id 23C74CE1940; Tue, 14 Nov 2023 23:17:48 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2BDD5C433C8; Tue, 14 Nov 2023 23:17:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1700003866; bh=KB3X/TgdZDL/2SrctEZtbC9ABrG1q5tejZewZjojaG0=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=I2FtgASHqT0NQ8pvMyoHDKY0L776FVzQEP+8MaG5h3awzZ83eZZkVJ5tDMyqMY0jb uNf09+vkik6GFj+3lMsunyHL6E+r2LTs8yQweYL9C7/V0/hHwRijTrIX+w/vU+Tbus VWm/hOguMarPwLXKltXgnv9nM3o8N2knOblTYH/4= Date: Tue, 14 Nov 2023 15:17:45 -0800 From: Andrew Morton To: Baoquan He Cc: linux-kernel@vger.kernel.org, kexec@lists.infradead.org, x86@kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, ebiederm@xmission.com, takahiro.akashi@linaro.org Subject: Re: [PATCH 1/2] resource: add walk_system_ram_res_rev() Message-Id: <20231114151745.e77ed504b3fce325f54ec08e@linux-foundation.org> In-Reply-To: <20231114091658.228030-2-bhe@redhat.com> References: <20231114091658.228030-1-bhe@redhat.com> <20231114091658.228030-2-bhe@redhat.com> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20231114_151750_876246_6CCE2567 X-CRM114-Status: GOOD ( 19.45 ) X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+kexec=archiver.kernel.org@lists.infradead.org On Tue, 14 Nov 2023 17:16:57 +0800 Baoquan He wrote: > This function, being a variant of walk_system_ram_res() introduced in > commit 8c86e70acead ("resource: provide new functions to walk through > resources"), walks through a list of all the resources of System RAM > in reversed order, i.e., from higher to lower. > > It will be used in kexec_file code to load kernel, initrd etc when > preparing kexec reboot. > > ... > > +/* > + * This function, being a variant of walk_system_ram_res(), calls the @func > + * callback against all memory ranges of type System RAM which are marked as > + * IORESOURCE_SYSTEM_RAM and IORESOUCE_BUSY in reversed order, i.e., from > + * higher to lower. > + */ > +int walk_system_ram_res_rev(u64 start, u64 end, void *arg, > + int (*func)(struct resource *, void *)) > +{ > + struct resource res, *rams; > + int rams_size = 16, i; > + unsigned long flags; > + int ret = -1; > + > + /* create a list */ > + rams = kvcalloc(rams_size, sizeof(struct resource), GFP_KERNEL); > + if (!rams) > + return ret; > + > + flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; > + i = 0; > + while ((start < end) && > + (!find_next_iomem_res(start, end, flags, IORES_DESC_NONE, &res))) { > + if (i >= rams_size) { > + /* re-alloc */ > + struct resource *rams_new; > + int rams_new_size; > + > + rams_new_size = rams_size + 16; > + rams_new = kvcalloc(rams_new_size, sizeof(struct resource), > + GFP_KERNEL); kvrealloc()? > + if (!rams_new) > + goto out; > + > + memcpy(rams_new, rams, > + sizeof(struct resource) * rams_size); > + kvfree(rams); > + rams = rams_new; > + rams_size = rams_new_size; > + } > + > + rams[i].start = res.start; > + rams[i++].end = res.end; > + > + start = res.end + 1; > + } > + > + /* go reverse */ > + for (i--; i >= 0; i--) { > + ret = (*func)(&rams[i], arg); > + if (ret) > + break; > + } > + > +out: > + kvfree(rams); > + return ret; > +} > + > /* > * This function calls the @func callback against all memory ranges, which > * are ranges marked as IORESOURCE_MEM and IORESOUCE_BUSY. > -- > 2.41.0 _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec