x86_64: make /proc/interrupts work with dyn irq_desc
[safe/jmp/linux-2.6] / fs / proc / task_mmu.c
index f0df310..4806830 100644 (file)
@@ -210,23 +210,20 @@ static int show_map(struct seq_file *m, void *v)
        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;
                ino = inode->i_ino;
        }
 
-       seq_printf(m, "%08lx-%08lx %c%c%c%c %08lx %02x:%02x %lu %n",
+       seq_printf(m, "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu %n",
                        vma->vm_start,
                        vma->vm_end,
                        flags & VM_READ ? 'r' : '-',
                        flags & VM_WRITE ? 'w' : '-',
                        flags & VM_EXEC ? 'x' : '-',
                        flags & VM_MAYSHARE ? 's' : 'p',
-                       vma->vm_pgoff << PAGE_SHIFT,
+                       ((loff_t)vma->vm_pgoff) << PAGE_SHIFT,
                        MAJOR(dev), MINOR(dev), ino, &len);
 
        /*
@@ -476,10 +473,10 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf,
                return -ESRCH;
        mm = get_task_mm(task);
        if (mm) {
-               static struct mm_walk clear_refs_walk;
-               memset(&clear_refs_walk, 0, sizeof(clear_refs_walk));
-               clear_refs_walk.pmd_entry = clear_refs_pte_range;
-               clear_refs_walk.mm = mm;
+               struct mm_walk clear_refs_walk = {
+                       .pmd_entry = clear_refs_pte_range,
+                       .mm = mm,
+               };
                down_read(&mm->mmap_sem);
                for (vma = mm->mmap; vma; vma = vma->vm_next) {
                        clear_refs_walk.private = vma;
@@ -553,24 +550,45 @@ static u64 swap_pte_to_pagemap_entry(pte_t pte)
        return swp_type(e) | (swp_offset(e) << MAX_SWAPFILES_SHIFT);
 }
 
+static unsigned long pte_to_pagemap_entry(pte_t pte)
+{
+       unsigned long pme = 0;
+       if (is_swap_pte(pte))
+               pme = PM_PFRAME(swap_pte_to_pagemap_entry(pte))
+                       | PM_PSHIFT(PAGE_SHIFT) | PM_SWAP;
+       else if (pte_present(pte))
+               pme = PM_PFRAME(pte_pfn(pte))
+                       | PM_PSHIFT(PAGE_SHIFT) | PM_PRESENT;
+       return pme;
+}
+
 static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
                             struct mm_walk *walk)
 {
+       struct vm_area_struct *vma;
        struct pagemapread *pm = walk->private;
        pte_t *pte;
        int err = 0;
 
+       /* find the first VMA at or above 'addr' */
+       vma = find_vma(walk->mm, addr);
        for (; addr != end; addr += PAGE_SIZE) {
                u64 pfn = PM_NOT_PRESENT;
-               pte = pte_offset_map(pmd, addr);
-               if (is_swap_pte(*pte))
-                       pfn = PM_PFRAME(swap_pte_to_pagemap_entry(*pte))
-                               | PM_PSHIFT(PAGE_SHIFT) | PM_SWAP;
-               else if (pte_present(*pte))
-                       pfn = PM_PFRAME(pte_pfn(*pte))
-                               | PM_PSHIFT(PAGE_SHIFT) | PM_PRESENT;
-               /* unmap so we're not in atomic when we copy to userspace */
-               pte_unmap(pte);
+
+               /* check to see if we've left 'vma' behind
+                * and need a new, higher one */
+               if (vma && (addr >= vma->vm_end))
+                       vma = find_vma(walk->mm, addr);
+
+               /* check that 'vma' actually covers this address,
+                * and that it isn't a huge page vma */
+               if (vma && (vma->vm_start <= addr) &&
+                   !is_vm_hugetlb_page(vma)) {
+                       pte = pte_offset_map(pmd, addr);
+                       pfn = pte_to_pagemap_entry(*pte);
+                       /* unmap before userspace copy */
+                       pte_unmap(pte);
+               }
                err = add_to_pagemap(addr, pfn, pm);
                if (err)
                        return err;
@@ -581,11 +599,6 @@ static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
        return err;
 }
 
-static struct mm_walk pagemap_walk = {
-       .pmd_entry = pagemap_pte_range,
-       .pte_hole = pagemap_pte_hole
-};
-
 /*
  * /proc/pid/pagemap - an array mapping virtual pages to pfns
  *
@@ -620,12 +633,17 @@ static ssize_t pagemap_read(struct file *file, char __user *buf,
        struct pagemapread pm;
        int pagecount;
        int ret = -ESRCH;
+       struct mm_walk pagemap_walk = {};
+       unsigned long src;
+       unsigned long svpfn;
+       unsigned long start_vaddr;
+       unsigned long end_vaddr;
 
        if (!task)
                goto out;
 
        ret = -EACCES;
-       if (!ptrace_may_attach(task))
+       if (!ptrace_may_access(task, PTRACE_MODE_READ))
                goto out_task;
 
        ret = -EINVAL;
@@ -638,11 +656,15 @@ static ssize_t pagemap_read(struct file *file, char __user *buf,
        if (!mm)
                goto out_task;
 
-       ret = -ENOMEM;
+
        uaddr = (unsigned long)buf & PAGE_MASK;
        uend = (unsigned long)(buf + count);
        pagecount = (PAGE_ALIGN(uend) - uaddr) / PAGE_SIZE;
-       pages = kmalloc(pagecount * sizeof(struct page *), GFP_KERNEL);
+       ret = 0;
+       if (pagecount == 0)
+               goto out_mm;
+       pages = kcalloc(pagecount, sizeof(struct page *), GFP_KERNEL);
+       ret = -ENOMEM;
        if (!pages)
                goto out_mm;
 
@@ -663,33 +685,33 @@ static ssize_t pagemap_read(struct file *file, char __user *buf,
        pm.out = (u64 *)buf;
        pm.end = (u64 *)(buf + count);
 
-       if (!ptrace_may_attach(task)) {
-               ret = -EIO;
-       } else {
-               unsigned long src = *ppos;
-               unsigned long svpfn = src / PM_ENTRY_BYTES;
-               unsigned long start_vaddr = svpfn << PAGE_SHIFT;
-               unsigned long end_vaddr = TASK_SIZE_OF(task);
-
-               /* watch out for wraparound */
-               if (svpfn > TASK_SIZE_OF(task) >> PAGE_SHIFT)
-                       start_vaddr = end_vaddr;
-
-               /*
-                * The odds are that this will stop walking way
-                * before end_vaddr, because the length of the
-                * user buffer is tracked in "pm", and the walk
-                * will stop when we hit the end of the buffer.
-                */
-               ret = walk_page_range(start_vaddr, end_vaddr,
-                                       &pagemap_walk);
-               if (ret == PM_END_OF_BUFFER)
-                       ret = 0;
-               /* don't need mmap_sem for these, but this looks cleaner */
-               *ppos += (char *)pm.out - buf;
-               if (!ret)
-                       ret = (char *)pm.out - buf;
-       }
+       pagemap_walk.pmd_entry = pagemap_pte_range;
+       pagemap_walk.pte_hole = pagemap_pte_hole;
+       pagemap_walk.mm = mm;
+       pagemap_walk.private = &pm;
+
+       src = *ppos;
+       svpfn = src / PM_ENTRY_BYTES;
+       start_vaddr = svpfn << PAGE_SHIFT;
+       end_vaddr = TASK_SIZE_OF(task);
+
+       /* watch out for wraparound */
+       if (svpfn > TASK_SIZE_OF(task) >> PAGE_SHIFT)
+               start_vaddr = end_vaddr;
+
+       /*
+        * The odds are that this will stop walking way
+        * before end_vaddr, because the length of the
+        * user buffer is tracked in "pm", and the walk
+        * will stop when we hit the end of the buffer.
+        */
+       ret = walk_page_range(start_vaddr, end_vaddr, &pagemap_walk);
+       if (ret == PM_END_OF_BUFFER)
+               ret = 0;
+       /* don't need mmap_sem for these, but this looks cleaner */
+       *ppos += (char *)pm.out - buf;
+       if (!ret)
+               ret = (char *)pm.out - buf;
 
 out_pages:
        for (; pagecount; pagecount--) {
@@ -717,22 +739,11 @@ const struct file_operations proc_pagemap_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 const struct seq_operations proc_pid_numa_maps_op = {
         .start  = m_start,
         .next   = m_next,
         .stop   = m_stop,
-        .show   = show_numa_map_checked
+        .show   = show_numa_map,
 };
 
 static int numa_maps_open(struct inode *inode, struct file *file)