From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120] helo=us-smtp-1.mimecast.com) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jpN3a-00013J-Al for kexec@lists.infradead.org; Sun, 28 Jun 2020 02:28:35 +0000 Subject: Re: [PATCH 01/11] kexec_file: allow archs to handle special regions while locating memory hole References: <159319825403.16351.7253978047621755765.stgit@hbathini.in.ibm.com> <159319828304.16351.6990340111766605842.stgit@hbathini.in.ibm.com> From: piliu Message-ID: Date: Sun, 28 Jun 2020 10:28:15 +0800 MIME-Version: 1.0 In-Reply-To: <159319828304.16351.6990340111766605842.stgit@hbathini.in.ibm.com> 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+dwmw2=infradead.org@lists.infradead.org To: Hari Bathini , Michael Ellerman , Andrew Morton Cc: Kexec-ml , Petr Tesarik , Mahesh J Salgaonkar , Sourabh Jain , lkml , linuxppc-dev , Mimi Zohar , Thiago Jung Bauermann , Dave Young , Vivek Goyal , Eric Biederman Hi Hari, If in [4/11], get_exclude_memory_ranges() turns out to be unnecessary ,then this patch is abundant either. As my understanding, memblock has already helped to achieved the purpose that get_exclude_memory_ranges() wants. Thanks, Pingfan On 06/27/2020 03:04 AM, Hari Bathini wrote: > Some archs can have special memory regions, within the given memory > range, which can't be used for the buffer in a kexec segment. As > kexec_add_buffer() function is being called from generic code as well, > add weak arch_kexec_add_buffer definition for archs to override & take > care of special regions before trying to locate a memory hole. > > Signed-off-by: Hari Bathini > --- > include/linux/kexec.h | 5 +++++ > kernel/kexec_file.c | 37 +++++++++++++++++++++++++++++++++---- > 2 files changed, 38 insertions(+), 4 deletions(-) > > diff --git a/include/linux/kexec.h b/include/linux/kexec.h > index 1776eb2..1237682 100644 > --- a/include/linux/kexec.h > +++ b/include/linux/kexec.h > @@ -195,6 +195,11 @@ int __weak arch_kexec_apply_relocations(struct purgatory_info *pi, > const Elf_Shdr *relsec, > const Elf_Shdr *symtab); > > +extern int arch_kexec_add_buffer(struct kexec_buf *kbuf); > + > +/* arch_kexec_add_buffer calls this when it is ready */ > +extern int __kexec_add_buffer(struct kexec_buf *kbuf); > + > extern int kexec_add_buffer(struct kexec_buf *kbuf); > int kexec_locate_mem_hole(struct kexec_buf *kbuf); > > diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c > index bb05fd5..a0b4f7f 100644 > --- a/kernel/kexec_file.c > +++ b/kernel/kexec_file.c > @@ -669,10 +669,6 @@ int kexec_locate_mem_hole(struct kexec_buf *kbuf) > */ > int kexec_add_buffer(struct kexec_buf *kbuf) > { > - > - struct kexec_segment *ksegment; > - int ret; > - > /* Currently adding segment this way is allowed only in file mode */ > if (!kbuf->image->file_mode) > return -EINVAL; > @@ -696,6 +692,25 @@ int kexec_add_buffer(struct kexec_buf *kbuf) > kbuf->memsz = ALIGN(kbuf->memsz, PAGE_SIZE); > kbuf->buf_align = max(kbuf->buf_align, PAGE_SIZE); > > + return arch_kexec_add_buffer(kbuf); > +} > + > +/** > + * __kexec_add_buffer - arch_kexec_add_buffer would call this function after > + * updating kbuf, to place a buffer in a kexec segment. > + * @kbuf: Buffer contents and memory parameters. > + * > + * This function assumes that kexec_mutex is held. > + * On successful return, @kbuf->mem will have the physical address of > + * the buffer in memory. > + * > + * Return: 0 on success, negative errno on error. > + */ > +int __kexec_add_buffer(struct kexec_buf *kbuf) > +{ > + struct kexec_segment *ksegment; > + int ret; > + > /* Walk the RAM ranges and allocate a suitable range for the buffer */ > ret = kexec_locate_mem_hole(kbuf); > if (ret) > @@ -711,6 +726,20 @@ int kexec_add_buffer(struct kexec_buf *kbuf) > return 0; > } > > +/** > + * arch_kexec_add_buffer - Some archs have memory regions within the given > + * range that can't be used to place a kexec segment. > + * Such archs can override this function to take care > + * of them before trying to locate the memory hole. > + * @kbuf: Buffer contents and memory parameters. > + * > + * Return: 0 on success, negative errno on error. > + */ > +int __weak arch_kexec_add_buffer(struct kexec_buf *kbuf) > +{ > + return __kexec_add_buffer(kbuf); > +} > + > /* Calculate and store the digest of segments */ > static int kexec_calculate_store_digests(struct kimage *image) > { > > > _______________________________________________ > kexec mailing list > kexec@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/kexec > _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec