X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=fs%2Fproc%2Ftask_mmu.c;h=c24d81a5a040e2a91825673434339e3c2f1dcdda;hb=1942971b20817def5fd1142248307c7c3c51fc8a;hp=199088ee969b1ec956fb85337e614c9ec42c92ab;hpb=f79f177c25016647cc92ffac8afa7cb96ce47011;p=linux-2.6 diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 199088ee96..c24d81a5a0 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -3,6 +3,7 @@ #include #include #include +#include #include #include @@ -142,6 +143,9 @@ static int show_map_internal(struct seq_file *m, void *v, struct mem_size_stats dev_t dev = 0; int len; + if (maps_protect && !ptrace_may_attach(task)) + return -EACCES; + if (file) { struct inode *inode = vma->vm_file->f_path.dentry->d_inode; dev = inode->i_sb->s_dev; @@ -195,7 +199,7 @@ static int show_map_internal(struct seq_file *m, void *v, struct mem_size_stats "Shared_Dirty: %8lu kB\n" "Private_Clean: %8lu kB\n" "Private_Dirty: %8lu kB\n" - "Pgs_Referenced: %8lu kB\n", + "Referenced: %8lu kB\n", (vma->vm_end - vma->vm_start) >> 10, mss->resident >> 10, mss->shared_clean >> 10, @@ -214,9 +218,9 @@ static int show_map(struct seq_file *m, void *v) return show_map_internal(m, v, NULL); } -static void smaps_one_pmd(struct vm_area_struct *vma, pmd_t *pmd, - unsigned long addr, unsigned long end, - void *private) +static void smaps_pte_range(struct vm_area_struct *vma, pmd_t *pmd, + unsigned long addr, unsigned long end, + void *private) { struct mem_size_stats *mss = private; pte_t *pte, ptent; @@ -254,8 +258,34 @@ static void smaps_one_pmd(struct vm_area_struct *vma, pmd_t *pmd, cond_resched(); } -static inline void for_each_pmd_in_pud(struct pmd_walker *walker, pud_t *pud, - unsigned long addr, unsigned long end) +static void clear_refs_pte_range(struct vm_area_struct *vma, pmd_t *pmd, + unsigned long addr, unsigned long end, + void *private) +{ + pte_t *pte, ptent; + spinlock_t *ptl; + struct page *page; + + pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); + for (; addr != end; pte++, addr += PAGE_SIZE) { + ptent = *pte; + if (!pte_present(ptent)) + continue; + + page = vm_normal_page(vma, addr, ptent); + if (!page) + continue; + + /* Clear accessed and referenced bits. */ + ptep_test_and_clear_young(vma, addr, pte); + ClearPageReferenced(page); + } + pte_unmap_unlock(pte - 1, ptl); + cond_resched(); +} + +static inline void walk_pmd_range(struct pmd_walker *walker, pud_t *pud, + unsigned long addr, unsigned long end) { pmd_t *pmd; unsigned long next; @@ -269,8 +299,8 @@ static inline void for_each_pmd_in_pud(struct pmd_walker *walker, pud_t *pud, } } -static inline void for_each_pud_in_pgd(struct pmd_walker *walker, pgd_t *pgd, - unsigned long addr, unsigned long end) +static inline void walk_pud_range(struct pmd_walker *walker, pgd_t *pgd, + unsigned long addr, unsigned long end) { pud_t *pud; unsigned long next; @@ -280,15 +310,24 @@ static inline void for_each_pud_in_pgd(struct pmd_walker *walker, pgd_t *pgd, next = pud_addr_end(addr, end); if (pud_none_or_clear_bad(pud)) continue; - for_each_pmd_in_pud(walker, pud, addr, next); + walk_pmd_range(walker, pud, addr, next); } } -static inline void for_each_pmd(struct vm_area_struct *vma, - void (*action)(struct vm_area_struct *, pmd_t *, - unsigned long, unsigned long, - void *), - void *private) +/* + * walk_page_range - walk the page tables of a VMA with a callback + * @vma - VMA to walk + * @action - callback invoked for every bottom-level (PTE) page table + * @private - private data passed to the callback function + * + * Recursively walk the page table for the memory area in a VMA, calling + * a callback for every bottom-level (PTE) page table. + */ +static inline void walk_page_range(struct vm_area_struct *vma, + void (*action)(struct vm_area_struct *, + pmd_t *, unsigned long, + unsigned long, void *), + void *private) { unsigned long addr = vma->vm_start; unsigned long end = vma->vm_end; @@ -305,7 +344,7 @@ static inline void for_each_pmd(struct vm_area_struct *vma, next = pgd_addr_end(addr, end); if (pgd_none_or_clear_bad(pgd)) continue; - for_each_pud_in_pgd(&walker, pgd, addr, next); + walk_pud_range(&walker, pgd, addr, next); } } @@ -316,10 +355,22 @@ static int show_smap(struct seq_file *m, void *v) memset(&mss, 0, sizeof mss); if (vma->vm_mm && !is_vm_hugetlb_page(vma)) - for_each_pmd(vma, smaps_one_pmd, &mss); + walk_page_range(vma, smaps_pte_range, &mss); return show_map_internal(m, v, &mss); } +void clear_refs_smap(struct mm_struct *mm) +{ + struct vm_area_struct *vma; + + down_read(&mm->mmap_sem); + for (vma = mm->mmap; vma; vma = vma->vm_next) + if (vma->vm_mm && !is_vm_hugetlb_page(vma)) + walk_page_range(vma, clear_refs_pte_range, NULL); + flush_tlb_mm(mm); + up_read(&mm->mmap_sem); +} + static void *m_start(struct seq_file *m, loff_t *pos) { struct proc_maps_private *priv = m->private; @@ -465,11 +516,22 @@ const struct file_operations proc_maps_operations = { #ifdef CONFIG_NUMA extern int show_numa_map(struct seq_file *m, void *v); +static int show_numa_map_checked(struct seq_file *m, void *v) +{ + struct proc_maps_private *priv = m->private; + struct task_struct *task = priv->task; + + if (maps_protect && !ptrace_may_attach(task)) + return -EACCES; + + return show_numa_map(m, v); +} + static struct seq_operations proc_pid_numa_maps_op = { .start = m_start, .next = m_next, .stop = m_stop, - .show = show_numa_map + .show = show_numa_map_checked }; static int numa_maps_open(struct inode *inode, struct file *file)