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author | Ingo Molnar <mingo@elte.hu> | 2008-10-28 16:54:49 +0100 |
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committer | Ingo Molnar <mingo@elte.hu> | 2008-10-28 16:54:49 +0100 |
commit | d1a76187a5be4f89c6cb19d800cb5fb7aac735c5 (patch) | |
tree | 2fac3ffbfffc7560eeef8364b541d0d7a0057920 /arch/ia64/xen/xencomm.c | |
parent | lockstat: contend with points (diff) | |
parent | Linux 2.6.28-rc2 (diff) | |
download | linux-d1a76187a5be4f89c6cb19d800cb5fb7aac735c5.tar.xz linux-d1a76187a5be4f89c6cb19d800cb5fb7aac735c5.zip |
Merge commit 'v2.6.28-rc2' into core/locking
Conflicts:
arch/um/include/asm/system.h
Diffstat (limited to 'arch/ia64/xen/xencomm.c')
-rw-r--r-- | arch/ia64/xen/xencomm.c | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/arch/ia64/xen/xencomm.c b/arch/ia64/xen/xencomm.c new file mode 100644 index 000000000000..1f5d7ac82e97 --- /dev/null +++ b/arch/ia64/xen/xencomm.c @@ -0,0 +1,105 @@ +/* + * Copyright (C) 2006 Hollis Blanchard <hollisb@us.ibm.com>, IBM Corporation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <linux/mm.h> + +static unsigned long kernel_virtual_offset; +static int is_xencomm_initialized; + +/* for xen early printk. It uses console io hypercall which uses xencomm. + * However early printk may use it before xencomm initialization. + */ +int +xencomm_is_initialized(void) +{ + return is_xencomm_initialized; +} + +void +xencomm_initialize(void) +{ + kernel_virtual_offset = KERNEL_START - ia64_tpa(KERNEL_START); + is_xencomm_initialized = 1; +} + +/* Translate virtual address to physical address. */ +unsigned long +xencomm_vtop(unsigned long vaddr) +{ + struct page *page; + struct vm_area_struct *vma; + + if (vaddr == 0) + return 0UL; + + if (REGION_NUMBER(vaddr) == 5) { + pgd_t *pgd; + pud_t *pud; + pmd_t *pmd; + pte_t *ptep; + + /* On ia64, TASK_SIZE refers to current. It is not initialized + during boot. + Furthermore the kernel is relocatable and __pa() doesn't + work on addresses. */ + if (vaddr >= KERNEL_START + && vaddr < (KERNEL_START + KERNEL_TR_PAGE_SIZE)) + return vaddr - kernel_virtual_offset; + + /* In kernel area -- virtually mapped. */ + pgd = pgd_offset_k(vaddr); + if (pgd_none(*pgd) || pgd_bad(*pgd)) + return ~0UL; + + pud = pud_offset(pgd, vaddr); + if (pud_none(*pud) || pud_bad(*pud)) + return ~0UL; + + pmd = pmd_offset(pud, vaddr); + if (pmd_none(*pmd) || pmd_bad(*pmd)) + return ~0UL; + + ptep = pte_offset_kernel(pmd, vaddr); + if (!ptep) + return ~0UL; + + return (pte_val(*ptep) & _PFN_MASK) | (vaddr & ~PAGE_MASK); + } + + if (vaddr > TASK_SIZE) { + /* percpu variables */ + if (REGION_NUMBER(vaddr) == 7 && + REGION_OFFSET(vaddr) >= (1ULL << IA64_MAX_PHYS_BITS)) + ia64_tpa(vaddr); + + /* kernel address */ + return __pa(vaddr); + } + + /* XXX double-check (lack of) locking */ + vma = find_extend_vma(current->mm, vaddr); + if (!vma) + return ~0UL; + + /* We assume the page is modified. */ + page = follow_page(vma, vaddr, FOLL_WRITE | FOLL_TOUCH); + if (!page) + return ~0UL; + + return (page_to_pfn(page) << PAGE_SHIFT) | (vaddr & ~PAGE_MASK); +} |