diff options
Diffstat (limited to 'xen/arch/x86/setup.c')
| -rw-r--r-- | xen/arch/x86/setup.c | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/xen/arch/x86/setup.c b/xen/arch/x86/setup.c index 2b9dbe3e88..7437c84db5 100644 --- a/xen/arch/x86/setup.c +++ b/xen/arch/x86/setup.c @@ -82,6 +82,11 @@ boolean_param("noapic", skip_ioapic_setup); s8 __read_mostly xen_cpuidle = -1; boolean_param("cpuidle", xen_cpuidle); +#ifndef NDEBUG +unsigned long __initdata highmem_start; +size_param("highmem-start", highmem_start); +#endif + cpumask_t __read_mostly cpu_present_map; unsigned long __read_mostly xen_phys_start; @@ -788,6 +793,14 @@ void __init __start_xen(unsigned long mbi_p) modules_headroom = bzimage_headroom(bootstrap_map(mod), mod->mod_end); bootstrap_map(NULL); +#ifndef highmem_start + /* Don't allow split below 4Gb. */ + if ( highmem_start < GB(4) ) + highmem_start = 0; + else /* align to L3 entry boundary */ + highmem_start &= ~((1UL << L3_PAGETABLE_SHIFT) - 1); +#endif + for ( i = boot_e820.nr_map-1; i >= 0; i-- ) { uint64_t s, e, mask = (1UL << L2_PAGETABLE_SHIFT) - 1; @@ -916,6 +929,9 @@ void __init __start_xen(unsigned long mbi_p) /* Don't overlap with other modules. */ end = consider_modules(s, e, size, mod, mbi->mods_count, j); + if ( highmem_start && end > highmem_start ) + continue; + if ( s < end && (headroom || ((end - size) >> PAGE_SHIFT) > mod[j].mod_start) ) @@ -957,6 +973,8 @@ void __init __start_xen(unsigned long mbi_p) kexec_reserve_area(&boot_e820); setup_max_pdx(); + if ( highmem_start ) + xenheap_max_mfn(PFN_DOWN(highmem_start)); /* * Walk every RAM region and map it in its entirety (on x86/64, at least) @@ -1128,7 +1146,8 @@ void __init __start_xen(unsigned long mbi_p) unsigned long limit = virt_to_mfn(HYPERVISOR_VIRT_END - 1); uint64_t mask = PAGE_SIZE - 1; - xenheap_max_mfn(limit); + if ( !highmem_start ) + xenheap_max_mfn(limit); /* Pass the remaining memory to the allocator. */ for ( i = 0; i < boot_e820.nr_map; i++ ) |