From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Jan Beulich" Subject: [PATCH] x86/32on64: fix physical address restriction Date: Thu, 12 Jun 2008 15:28:59 +0100 Message-ID: <48514ECB.76E4.0078.0@novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Return-path: Content-Disposition: inline List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org The allocation bit size setting wasn't working anymore after the recent fix to properly use PAGE_SHIFT instead of PAGE_SIZE. This was because the bit size implies a power-of-two range that's accessible, but if all memory is accessible anyway (and its upper boundary is not a power of two), the domain would either be needlessly restricted or wouldn't be able to allocate as much memory as was intended for it (specifically the case for Dom0 without dom0_mem=3D boot parameter). Consequently, don't restrict the bit width if all memory can be accessed. To avoid needing to adjust this code in two places in the future (it may need further touching when memory hotplug gets supported), fold the logic into a function. Signed-off-by: Jan Beulich Index: 2008-06-12/xen/arch/x86/domain.c =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D --- 2008-06-12.orig/xen/arch/x86/domain.c 2008-06-12 09:02:00.0000000= 00 +0200 +++ 2008-06-12/xen/arch/x86/domain.c 2008-06-12 09:07:02.000000000 = +0200 @@ -349,11 +349,7 @@ int switch_compat(struct domain *d) FIRST_RESERVED_GDT_PAGE)] =3D gdt_l1e; } =20 - d->arch.physaddr_bitsize =3D - /* 2^n entries can be contained in guest's p2m mapping space */ - fls((1UL << 32) - HYPERVISOR_COMPAT_VIRT_START(d)) - 3 - /* 2^n pages -> 2^(n+PAGE_SHIFT) bits */ - + PAGE_SHIFT; + domain_set_alloc_bitsize(d); =20 return 0; =20 Index: 2008-06-12/xen/arch/x86/domain_build.c =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D --- 2008-06-12.orig/xen/arch/x86/domain_build.c 2008-06-10 18:00:41.0000000= 00 +0200 +++ 2008-06-12/xen/arch/x86/domain_build.c 2008-06-12 09:08:19.0000000= 00 +0200 @@ -353,14 +353,7 @@ int __init construct_dom0( #endif } =20 -#if defined(__x86_64__) - if ( is_pv_32on64_domain(d) ) - d->arch.physaddr_bitsize =3D - /* 2^n entries can be contained in guest's p2m mapping space = */ - fls((1UL << 32) - HYPERVISOR_COMPAT_VIRT_START(d)) - 3 - /* 2^n pages -> 2^(n+PAGE_SHIFT) bits */ - + PAGE_SHIFT; -#endif + domain_set_alloc_bitsize(d); =20 /* * Why do we need this? The number of page-table frames depends on = the=20 Index: 2008-06-12/xen/arch/x86/x86_64/mm.c =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D --- 2008-06-12.orig/xen/arch/x86/x86_64/mm.c 2008-06-10 18:00:41.0000000= 00 +0200 +++ 2008-06-12/xen/arch/x86/x86_64/mm.c 2008-06-12 09:07:42.000000000 = +0200 @@ -470,9 +470,21 @@ int check_descriptor(const struct domain return 0; } =20 +void domain_set_alloc_bitsize(struct domain *d) +{ + if ( !is_pv_32on64_domain(d) + || HYPERVISOR_COMPAT_VIRT_START(d) > __HYPERVISOR_COMPAT_VIRT_STA= RT ) + return; + d->arch.physaddr_bitsize =3D + /* 2^n entries can be contained in guest's p2m mapping space */ + fls((1UL << 32) - HYPERVISOR_COMPAT_VIRT_START(d)) - 3 + /* 2^n pages -> 2^(n+PAGE_SHIFT) bits */ + + PAGE_SHIFT; +} + unsigned int domain_clamp_alloc_bitsize(struct domain *d, unsigned int = bits) { - if ( (d =3D=3D NULL) || !is_pv_32on64_domain(d) ) + if ( d =3D=3D NULL || d->arch.physaddr_bitsize =3D=3D 0 ) return bits; return min(d->arch.physaddr_bitsize, bits); } Index: 2008-06-12/xen/include/asm-x86/mm.h =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D --- 2008-06-12.orig/xen/include/asm-x86/mm.h 2008-05-09 09:48:32.0000000= 00 +0200 +++ 2008-06-12/xen/include/asm-x86/mm.h 2008-06-12 09:06:20.000000000 = +0200 @@ -343,9 +343,11 @@ int map_ldt_shadow_page(unsigned int); =20 #ifdef CONFIG_COMPAT int setup_arg_xlat_area(struct vcpu *, l4_pgentry_t *); +void domain_set_alloc_bitsize(struct domain *d); unsigned int domain_clamp_alloc_bitsize(struct domain *d, unsigned int = bits); #else # define setup_arg_xlat_area(vcpu, l4tab) 0 +# define domain_set_alloc_bitsize(d) ((void)0) # define domain_clamp_alloc_bitsize(d, b) (b) #endif =20