static unsigned long __init compute_dom0_nr_pages(void)
{
unsigned long avail = avail_domheap_pages() + initial_images_nrpages();
/*
* If domain 0 allocation isn't specified, reserve 1/16th of available
* memory for things like DMA buffers. This reservation is clamped to
* a maximum of 128MB.
*/
if ( dom0_nrpages == 0 )
{
dom0_nrpages = avail;
dom0_nrpages = min(dom0_nrpages / 16, 128L << (20 - PAGE_SHIFT));
dom0_nrpages = -dom0_nrpages;
}
/* Negative memory specification means "all memory - specified amount". */
if ( dom0_nrpages < 0 ) dom0_nrpages += avail;
if ( dom0_min_nrpages < 0 ) dom0_min_nrpages += avail;
if ( dom0_max_nrpages < 0 ) dom0_max_nrpages += avail;
/* Clamp dom0 memory according to min/max limits and available memory. */
dom0_nrpages = max(dom0_nrpages, dom0_min_nrpages);
dom0_nrpages = min(dom0_nrpages, dom0_max_nrpages);
dom0_nrpages = min(dom0_nrpages, (long)avail);
return dom0_nrpages;
}
static unsigned long __init compute_dom0_nr_pages(
struct domain *d, struct elf_dom_parms *parms, unsigned long initrd_len)
{
unsigned long avail = avail_domheap_pages() + initial_images_nrpages();
unsigned long nr_pages = dom0_nrpages;
unsigned long min_pages = dom0_min_nrpages;
unsigned long max_pages = dom0_max_nrpages;
/* Reserve memory for further dom0 vcpu-struct allocations... */
avail -= (opt_dom0_max_vcpus - 1UL)
<< get_order_from_bytes(sizeof(struct vcpu));
/* ...and compat_l4's, if needed. */
if ( is_pv_32on64_domain(d) )
avail -= opt_dom0_max_vcpus - 1;
/* Reserve memory for iommu_dom0_init() (rough estimate). */
if ( iommu_enabled )
{
unsigned int s;
for ( s = 9; s < BITS_PER_LONG; s += 9 )
avail -= max_pdx >> s;
}
/*
* If domain 0 allocation isn't specified, reserve 1/16th of available
* memory for things like DMA buffers. This reservation is clamped to
* a maximum of 128MB.
*/
if ( nr_pages == 0 )
nr_pages = -min(avail / 16, 128UL << (20 - PAGE_SHIFT));
/* Negative memory specification means "all memory - specified amount". */
if ( (long)nr_pages < 0 ) nr_pages += avail;
if ( (long)min_pages < 0 ) min_pages += avail;
if ( (long)max_pages < 0 ) max_pages += avail;
/* Clamp dom0 memory according to min/max limits and available memory. */
nr_pages = max(nr_pages, min_pages);
nr_pages = min(nr_pages, max_pages);
nr_pages = min(nr_pages, avail);
#ifdef __x86_64__
if ( (parms->p2m_base == UNSET_ADDR) && (dom0_nrpages <= 0) &&
((dom0_min_nrpages <= 0) || (nr_pages > min_pages)) )
{
/*
* Legacy Linux kernels (i.e. such without a XEN_ELFNOTE_INIT_P2M
* note) require that there is enough virtual space beyond the initial
* allocation to set up their initial page tables. This space is
* roughly the same size as the p2m table, so make sure the initial
* allocation doesn't consume more than about half the space that's
* available between params.virt_base and the address space end.
*/
unsigned long vstart, vend, end;
size_t sizeof_long = is_pv_32bit_domain(d) ? sizeof(int) : sizeof(long);
vstart = parms->virt_base;
vend = round_pgup(parms->virt_kend);
if ( !parms->elf_notes[XEN_ELFNOTE_MOD_START_PFN].data.num )
vend += round_pgup(initrd_len);
end = vend + nr_pages * sizeof_long;
if ( end > vstart )
end += end - vstart;
if ( end <= vstart ||
(sizeof_long < sizeof(end) && end > (1UL << (8 * sizeof_long))) )
{
end = sizeof_long >= sizeof(end) ? 0 : 1UL << (8 * sizeof_long);
nr_pages = (end - vend) / (2 * sizeof_long);
if ( dom0_min_nrpages > 0 && nr_pages < min_pages )
nr_pages = min_pages;
printk("Dom0 memory clipped to %lu pages\n", nr_pages);
}
}
#endif
d->max_pages = min_t(unsigned long, max_pages, UINT_MAX);
return nr_pages;
}
if ( (max_pages & (max_pages-1)) != 0 )
order--;
while ( (page = alloc_domheap_pages(d, order, 0)) == NULL )
if ( order-- == 0 )
break;
return page;
}
static unsigned long __init compute_dom0_nr_pages(
#ifdef __x86_64__
unsigned long vstart, unsigned long vend, size_t sizeof_long)
#else
void)
#endif
{
unsigned long avail = avail_domheap_pages() + initial_images_nrpages();
unsigned long nr_pages = dom0_nrpages;
unsigned long min_pages = dom0_min_nrpages;
unsigned long max_pages = dom0_max_nrpages;
/*
* If domain 0 allocation isn't specified, reserve 1/16th of available
* memory for things like DMA buffers. This reservation is clamped to
* a maximum of 128MB.
*/
if ( nr_pages == 0 )
nr_pages = -min(avail / 16, 128UL << (20 - PAGE_SHIFT));
/* Negative memory specification means "all memory - specified amount". */
if ( (long)nr_pages < 0 ) nr_pages += avail;
if ( (long)min_pages < 0 ) min_pages += avail;
