Re: [XenPPC] xm save: adding couple domctl operations to access htab
> I don't know if I'm off base but have you added appropriate code to > linux? specifically arch/powerpc/platforms/xen/hcall.c ? Yes, this was the problem, but I had been looking at xen/arch/powerpc/hcalls.c, not realizing that you were pointing-out a different file... In face hcall.c resides on linux side while hcalls.c is part of xen. Also was surprise to me that linux was involved in this way... Somehow when Jimi spelled-out more detail, I finally realized a 2nd file was involved. Anyway, thanks for trying ;-) ___ Xen-ppc-devel mailing list Xen-ppc-devel@lists.xensource.com http://lists.xensource.com/xen-ppc-devel
Re: [XenPPC] xm save: adding couple domctl operations to access htab
On Oct 1, 2006, at 3:33 PM, Jimi Xenidis wrote: On Oct 1, 2006, at 1:20 PM, poff wrote: I don't know if I'm off base but have you added appropriate code to linux? specifically arch/powerpc/platforms/xen/hcall.c ? An existing hypercall, viz #36, do_domctl, provides several commands to access guest domains. For example, XEN_DOMCTL_getmemlist and XEN_DOMCTL_max_mem. Thought I would add another to copy the htab, XEN_DOMCTL_gethtab. So I think no modification is needed to hcall.c Sadly, there is: Some architectures require that the linux kernel has knowledge of all hcalls, and PPc is one of them you will notice in: arch/powerpc/platforms/xen/hcall.c: xenppc_privcmd_domctl() there is a huge switch statement for all the domctl OPs. If your case is not in the switch then you are subject to: default: printk(KERN_ERR "%s: unknown domctl cmd %d\n", __func__, kern_op.cmd); return -ENOSYS; } and hence your ENOSYS BTW: This message may not reach your dom0 console, you can either see it by running the dmesg command --or-- add "debug" to your dom0 kernel options. Adding "sysrq=1" may be may also be a good thing since init scripts usually disable sysrq. -JX ___ Xen-ppc-devel mailing list Xen-ppc-devel@lists.xensource.com http://lists.xensource.com/xen-ppc-devel
Re: [XenPPC] xm save: adding couple domctl operations to access htab
On Oct 1, 2006, at 1:20 PM, poff wrote: I don't know if I'm off base but have you added appropriate code to linux? specifically arch/powerpc/platforms/xen/hcall.c ? An existing hypercall, viz #36, do_domctl, provides several commands to access guest domains. For example, XEN_DOMCTL_getmemlist and XEN_DOMCTL_max_mem. Thought I would add another to copy the htab, XEN_DOMCTL_gethtab. So I think no modification is needed to hcall.c Sadly, there is: Some architectures require that the linux kernel has knowledge of all hcalls, and PPc is one of them you will notice in: arch/powerpc/platforms/xen/hcall.c: xenppc_privcmd_domctl() there is a huge switch statement for all the domctl OPs. If your case is not in the switch then you are subject to: default: printk(KERN_ERR "%s: unknown domctl cmd %d\n", __func__, kern_op.cmd); return -ENOSYS; } and hence your ENOSYS Since you are modeling the OP from XEN_DOMCTL_getmemlist, if you are reusing the data structure as well (which would make sense then the following diff should solve your problem: diff -r c52ba3176a28 arch/powerpc/platforms/xen/hcall.c --- a/arch/powerpc/platforms/xen/hcall.cThu Sep 28 12:26:59 2006 -0400 +++ b/arch/powerpc/platforms/xen/hcall.cSun Oct 01 15:30:45 2006 -0400 @@ -273,6 +273,7 @@ static int xenppc_privcmd_domctl(privcmd case XEN_DOMCTL_getdomaininfo: break; case XEN_DOMCTL_getmemlist: + case XEN_DOMCTL_gethtab: ret = xencomm_create( xen_guest_handle(kern_op.u.getmemlist.buffer), kern_op.u.getmemlist.max_pfns * sizeof(unsigned long), BTW: since we are trying to stick with Xen names "XEN_DOMCTL_getshadowlist" might be better, but at this point it is a name and can be debated later. -JX ___ Xen-ppc-devel mailing list Xen-ppc-devel@lists.xensource.com http://lists.xensource.com/xen-ppc-devel
Re: [XenPPC] xm save: adding couple domctl operations to access htab
> I don't know if I'm off base but have you added appropriate code to > linux? specifically arch/powerpc/platforms/xen/hcall.c ? An existing hypercall, viz #36, do_domctl, provides several commands to access guest domains. For example, XEN_DOMCTL_getmemlist and XEN_DOMCTL_max_mem. Thought I would add another to copy the htab, XEN_DOMCTL_gethtab. So I think no modification is needed to hcall.c The problem is hcall_xen() never sees the do_domctl hypercall when it includes the new command... On the tools side, do_xen_hypercall() receives the do_domctl, calls do_privcmd() which calls ioctl(). Looks like the tools is issuing the hypercall, but xen does not receive it... The tools application does receive the ENOSYS error, but cannot see where it is generated. ___ Xen-ppc-devel mailing list Xen-ppc-devel@lists.xensource.com http://lists.xensource.com/xen-ppc-devel
Re: [XenPPC] xm save: adding couple domctl operations to access htab
On Sat, Sep 30, 2006 at 05:29:40PM -0400, poff wrote: > When saving a domain, its htab must be copied, real page numbers replaced > with physical, > then written to disk. To copy the htab, I've tried for many hours to add a > domctl operation, > #define XEN_DOMCTL_gethtab 29, using code and structures similar to > XEN_DOMCTL_getmemlist. > > This new command makes it through do_xen_hypercall(), however, always get > ENOSYS returned... > On the Xen side, hcall_xen() I print all the command numbers for do_domctl > ops, but this > new command never arrives. Of course, have added a 'case XEN_DOMCTL_gethtab' > in domctl.c, > and also printk before ENOSYS, but this code is never run. > > 1) Is this a reasonable approach to copying the htab? > > 2) Any clues? I don't know if I'm off base but have you added appropriate code to linux? specifically arch/powerpc/platforms/xen/hcall.c ? Yours Tony linux.conf.au http://linux.conf.au/ || http://lca2007.linux.org.au/ Jan 15-20 2007 The Australian Linux Technical Conference! ___ Xen-ppc-devel mailing list Xen-ppc-devel@lists.xensource.com http://lists.xensource.com/xen-ppc-devel
[XenPPC] xm save: adding couple domctl operations to access htab
When saving a domain, its htab must be copied, real page numbers replaced with physical, then written to disk. To copy the htab, I've tried for many hours to add a domctl operation, #define XEN_DOMCTL_gethtab 29, using code and structures similar to XEN_DOMCTL_getmemlist. This new command makes it through do_xen_hypercall(), however, always get ENOSYS returned... On the Xen side, hcall_xen() I print all the command numbers for do_domctl ops, but this new command never arrives. Of course, have added a 'case XEN_DOMCTL_gethtab' in domctl.c, and also printk before ENOSYS, but this code is never run. 1) Is this a reasonable approach to copying the htab? 2) Any clues? ___ Xen-ppc-devel mailing list Xen-ppc-devel@lists.xensource.com http://lists.xensource.com/xen-ppc-devel
