From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: [PATCH] add compat wrapper for get_user_pages_fast Date: Thu, 18 Sep 2008 18:33:04 +0200 Message-ID: <48D282C0.3050100@siemens.com> References: <48D21065.5090602@siemens.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: "Xu, Jiajun" , kvm@vger.kernel.org, Marcelo Tosatti , Avi Kivity To: unlisted-recipients:; (no To-header on input) Return-path: Received: from lizzard.sbs.de ([194.138.37.39]:21019 "EHLO lizzard.sbs.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753368AbYIRQd0 (ORCPT ); Thu, 18 Sep 2008 12:33:26 -0400 In-Reply-To: <48D21065.5090602@siemens.com> Sender: kvm-owner@vger.kernel.org List-ID: Jan Kiszka wrote: > Xu, Jiajun wrote: >> Hi, >> Against latest kvm commit, 9644a6d164e3d6d0532ddb064393293134f31ab2. KVM >> compile meet error on 2.6.26.2. >> >> [root@kvm-build kernel]# make >> rm -f include/asm >> ln -sf asm-x86 include/asm >> ln -sf asm-x86 include-compat/asm >> make -C /lib/modules/2.6.26.2/build M=`pwd` \ >> LINUXINCLUDE="-I`pwd`/include -Iinclude >> -Iarch/x86/include -I`pwd`/include-compat \ >> -include include/linux/autoconf.h \ >> -include `pwd`/x86/external-module-compat.h" >> make[1]: Entering directory `/usr/src/redhat/BUILD/kernel-2.6.26.2' >> CC [M] /home/build/gitrepo/test/kvm-userspace/kernel/x86/kvm_main.o >> /home/build/gitrepo/test/kvm-userspace/kernel/x86/kvm_main.c: In >> function 'gfn_to_pfn': >> /home/build/gitrepo/test/kvm-userspace/kernel/x86/kvm_main.c:742: error: >> implicit declaration of function 'get_user_pages_fast' >> make[3]: *** >> [/home/build/gitrepo/test/kvm-userspace/kernel/x86/kvm_main.o] Error 1 >> make[2]: *** [/home/build/gitrepo/test/kvm-userspace/kernel/x86] Error 2 >> make[1]: *** [_module_/home/build/gitrepo/test/kvm-userspace/kernel] >> Error 2 >> make[1]: Leaving directory `/usr/src/redhat/BUILD/kernel-2.6.26.2' >> > > I can confirm this bug. Looks like Marcelo's get_user_pages_fast patches > lack corresponding compat wrapping (in kvm-userspace)... Not sure if this is correct, but here is at least a compile fix. Note that the original mmem_map locking scope was partly far broader on older kernels than with Marcelo's patch and this fix now. Could anyone comment on the correctness? --------- Signed-off-by: Jan Kiszka --- kernel/external-module-compat-comm.h | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) Index: b/kernel/external-module-compat-comm.h =================================================================== --- a/kernel/external-module-compat-comm.h +++ b/kernel/external-module-compat-comm.h @@ -531,3 +531,20 @@ struct pci_dev; struct pci_dev *pci_get_bus_and_slot(unsigned int bus, unsigned int devfn); #endif + +#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,27) + +static inline int get_user_pages_fast(unsigned long start, int nr_pages, + int write, struct page **pages) +{ + int npages; + + down_read(¤t->mm->mmap_sem); + npages = get_user_pages(current, current->mm, start, nr_pages, write, + 0, pages, NULL); + up_read(¤t->mm->mmap_sem); + + return npages; +} + +#endif