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	 5c83511bdb
			
		
	
	
		5c83511bdb
		
	
	
	
	
		
			
			Instead of using six globally visible paravirt ops structures combine them in a single structure, keeping the original structures as sub-structures. This avoids the need to assemble struct paravirt_patch_template at runtime on the stack each time apply_paravirt() is being called (i.e. when loading a module). [ tglx: Made the struct and the initializer tabular for readability sake ] Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: xen-devel@lists.xenproject.org Cc: virtualization@lists.linux-foundation.org Cc: akataria@vmware.com Cc: rusty@rustcorp.com.au Cc: boris.ostrovsky@oracle.com Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/20180828074026.820-9-jgross@suse.com
		
			
				
	
	
		
			81 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			81 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0
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| #include <linux/types.h>
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| #include <linux/crash_dump.h>
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| 
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| #include <xen/interface/xen.h>
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| #include <xen/hvm.h>
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| 
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| #include "mmu.h"
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| 
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| #ifdef CONFIG_PROC_VMCORE
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| /*
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|  * This function is used in two contexts:
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|  * - the kdump kernel has to check whether a pfn of the crashed kernel
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|  *   was a ballooned page. vmcore is using this function to decide
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|  *   whether to access a pfn of the crashed kernel.
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|  * - the kexec kernel has to check whether a pfn was ballooned by the
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|  *   previous kernel. If the pfn is ballooned, handle it properly.
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|  * Returns 0 if the pfn is not backed by a RAM page, the caller may
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|  * handle the pfn special in this case.
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|  */
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| static int xen_oldmem_pfn_is_ram(unsigned long pfn)
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| {
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| 	struct xen_hvm_get_mem_type a = {
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| 		.domid = DOMID_SELF,
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| 		.pfn = pfn,
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| 	};
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| 	int ram;
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| 
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| 	if (HYPERVISOR_hvm_op(HVMOP_get_mem_type, &a))
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| 		return -ENXIO;
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| 
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| 	switch (a.mem_type) {
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| 	case HVMMEM_mmio_dm:
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| 		ram = 0;
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| 		break;
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| 	case HVMMEM_ram_rw:
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| 	case HVMMEM_ram_ro:
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| 	default:
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| 		ram = 1;
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| 		break;
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| 	}
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| 
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| 	return ram;
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| }
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| #endif
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| 
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| static void xen_hvm_exit_mmap(struct mm_struct *mm)
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| {
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| 	struct xen_hvm_pagetable_dying a;
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| 	int rc;
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| 
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| 	a.domid = DOMID_SELF;
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| 	a.gpa = __pa(mm->pgd);
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| 	rc = HYPERVISOR_hvm_op(HVMOP_pagetable_dying, &a);
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| 	WARN_ON_ONCE(rc < 0);
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| }
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| 
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| static int is_pagetable_dying_supported(void)
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| {
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| 	struct xen_hvm_pagetable_dying a;
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| 	int rc = 0;
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| 
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| 	a.domid = DOMID_SELF;
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| 	a.gpa = 0x00;
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| 	rc = HYPERVISOR_hvm_op(HVMOP_pagetable_dying, &a);
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| 	if (rc < 0) {
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| 		printk(KERN_DEBUG "HVMOP_pagetable_dying not supported\n");
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| 		return 0;
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| 	}
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| 	return 1;
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| }
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| 
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| void __init xen_hvm_init_mmu_ops(void)
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| {
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| 	if (is_pagetable_dying_supported())
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| 		pv_ops.mmu.exit_mmap = xen_hvm_exit_mmap;
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| #ifdef CONFIG_PROC_VMCORE
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| 	WARN_ON(register_oldmem_pfn_is_ram(&xen_oldmem_pfn_is_ram));
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| #endif
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| }
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