diff options
Diffstat (limited to 'arch/um/kernel/skas/mmu.c')
-rw-r--r-- | arch/um/kernel/skas/mmu.c | 64 |
1 files changed, 29 insertions, 35 deletions
diff --git a/arch/um/kernel/skas/mmu.c b/arch/um/kernel/skas/mmu.c index 902d741..c5475ec 100644 --- a/arch/um/kernel/skas/mmu.c +++ b/arch/um/kernel/skas/mmu.c @@ -1,20 +1,12 @@ -/* - * Copyright (C) 2002 Jeff Dike (jdike@karaya.com) +/* + * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) * Licensed under the GPL */ -#include "linux/sched.h" -#include "linux/list.h" -#include "linux/spinlock.h" -#include "linux/slab.h" -#include "linux/errno.h" #include "linux/mm.h" -#include "asm/current.h" -#include "asm/segment.h" -#include "asm/mmu.h" +#include "linux/sched.h" #include "asm/pgalloc.h" #include "asm/pgtable.h" -#include "asm/ldt.h" #include "os.h" #include "skas.h" @@ -41,10 +33,11 @@ static int init_stub_pte(struct mm_struct *mm, unsigned long proc, if (!pte) goto out_pte; - /* There's an interaction between the skas0 stub pages, stack + /* + * There's an interaction between the skas0 stub pages, stack * randomization, and the BUG at the end of exit_mmap. exit_mmap - * checks that the number of page tables freed is the same as had - * been allocated. If the stack is on the last page table page, + * checks that the number of page tables freed is the same as had + * been allocated. If the stack is on the last page table page, * then the stack pte page will be freed, and if not, it won't. To * avoid having to know where the stack is, or if the process mapped * something at the top of its address space for some other reason, @@ -54,36 +47,37 @@ static int init_stub_pte(struct mm_struct *mm, unsigned long proc, * destroy_context_skas. */ - mm->context.skas.last_page_table = pmd_page_vaddr(*pmd); + mm->context.skas.last_page_table = pmd_page_vaddr(*pmd); #ifdef CONFIG_3_LEVEL_PGTABLES - mm->context.skas.last_pmd = (unsigned long) __va(pud_val(*pud)); + mm->context.skas.last_pmd = (unsigned long) __va(pud_val(*pud)); #endif *pte = mk_pte(virt_to_page(kernel), __pgprot(_PAGE_PRESENT)); *pte = pte_mkread(*pte); - return(0); + return 0; out_pmd: pud_free(pud); out_pte: pmd_free(pmd); out: - return(-ENOMEM); + return -ENOMEM; } int init_new_context(struct task_struct *task, struct mm_struct *mm) { - struct mmu_context_skas *from_mm = NULL; + struct mmu_context_skas *from_mm = NULL; struct mmu_context_skas *to_mm = &mm->context.skas; unsigned long stack = 0; int ret = -ENOMEM; - if(skas_needs_stub){ + if (skas_needs_stub) { stack = get_zeroed_page(GFP_KERNEL); - if(stack == 0) + if (stack == 0) goto out; - /* This zeros the entry that pgd_alloc didn't, needed since + /* + * This zeros the entry that pgd_alloc didn't, needed since * we are about to reinitialize it, and want mm.nr_ptes to * be accurate. */ @@ -91,39 +85,39 @@ int init_new_context(struct task_struct *task, struct mm_struct *mm) ret = init_stub_pte(mm, CONFIG_STUB_CODE, (unsigned long) &__syscall_stub_start); - if(ret) + if (ret) goto out_free; ret = init_stub_pte(mm, CONFIG_STUB_DATA, stack); - if(ret) + if (ret) goto out_free; mm->nr_ptes--; } to_mm->id.stack = stack; - if(current->mm != NULL && current->mm != &init_mm) + if (current->mm != NULL && current->mm != &init_mm) from_mm = ¤t->mm->context.skas; - if(proc_mm){ + if (proc_mm) { ret = new_mm(stack); - if(ret < 0){ - printk("init_new_context_skas - new_mm failed, " - "errno = %d\n", ret); + if (ret < 0) { + printk(KERN_ERR "init_new_context_skas - " + "new_mm failed, errno = %d\n", ret); goto out_free; } to_mm->id.u.mm_fd = ret; } else { - if(from_mm) + if (from_mm) to_mm->id.u.pid = copy_context_skas0(stack, from_mm->id.u.pid); else to_mm->id.u.pid = start_userspace(stack); } ret = init_new_ldt(to_mm, from_mm); - if(ret < 0){ - printk("init_new_context_skas - init_ldt" + if (ret < 0) { + printk(KERN_ERR "init_new_context_skas - init_ldt" " failed, errno = %d\n", ret); goto out_free; } @@ -131,7 +125,7 @@ int init_new_context(struct task_struct *task, struct mm_struct *mm) return 0; out_free: - if(to_mm->id.stack != 0) + if (to_mm->id.stack != 0) free_page(to_mm->id.stack); out: return ret; @@ -141,12 +135,12 @@ void destroy_context(struct mm_struct *mm) { struct mmu_context_skas *mmu = &mm->context.skas; - if(proc_mm) + if (proc_mm) os_close_file(mmu->id.u.mm_fd); else os_kill_ptraced_process(mmu->id.u.pid, 1); - if(!proc_mm || !ptrace_faultinfo){ + if (!proc_mm || !ptrace_faultinfo) { free_page(mmu->id.stack); pte_lock_deinit(virt_to_page(mmu->last_page_table)); pte_free_kernel((pte_t *) mmu->last_page_table); |