]> err.no Git - linux-2.6/blobdiff - fs/proc/task_mmu.c
Merge commit 'kumar/kumar-next'
[linux-2.6] / fs / proc / task_mmu.c
index 17403629e3304124b50ac0c3f6a4754e9c4f3135..7546a918f7907612b078c411d8eeb288b099ffc2 100644 (file)
@@ -210,7 +210,7 @@ static int show_map(struct seq_file *m, void *v)
        dev_t dev = 0;
        int len;
 
-       if (maps_protect && !ptrace_may_attach(task))
+       if (maps_protect && !ptrace_may_access(task, PTRACE_MODE_READ))
                return -EACCES;
 
        if (file) {
@@ -315,9 +315,9 @@ struct mem_size_stats {
 };
 
 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
-                          void *private)
+                          struct mm_walk *walk)
 {
-       struct mem_size_stats *mss = private;
+       struct mem_size_stats *mss = walk->private;
        struct vm_area_struct *vma = mss->vma;
        pte_t *pte, ptent;
        spinlock_t *ptl;
@@ -365,19 +365,21 @@ static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
        return 0;
 }
 
-static struct mm_walk smaps_walk = { .pmd_entry = smaps_pte_range };
-
 static int show_smap(struct seq_file *m, void *v)
 {
        struct vm_area_struct *vma = v;
        struct mem_size_stats mss;
        int ret;
+       struct mm_walk smaps_walk = {
+               .pmd_entry = smaps_pte_range,
+               .mm = vma->vm_mm,
+               .private = &mss,
+       };
 
        memset(&mss, 0, sizeof mss);
        mss.vma = vma;
        if (vma->vm_mm && !is_vm_hugetlb_page(vma))
-               walk_page_range(vma->vm_mm, vma->vm_start, vma->vm_end,
-                               &smaps_walk, &mss);
+               walk_page_range(vma->vm_start, vma->vm_end, &smaps_walk);
 
        ret = show_map(m, v);
        if (ret)
@@ -426,9 +428,9 @@ const struct file_operations proc_smaps_operations = {
 };
 
 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
-                               unsigned long end, void *private)
+                               unsigned long end, struct mm_walk *walk)
 {
-       struct vm_area_struct *vma = private;
+       struct vm_area_struct *vma = walk->private;
        pte_t *pte, ptent;
        spinlock_t *ptl;
        struct page *page;
@@ -452,8 +454,6 @@ static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
        return 0;
 }
 
-static struct mm_walk clear_refs_walk = { .pmd_entry = clear_refs_pte_range };
-
 static ssize_t clear_refs_write(struct file *file, const char __user *buf,
                                size_t count, loff_t *ppos)
 {
@@ -476,11 +476,17 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf,
                return -ESRCH;
        mm = get_task_mm(task);
        if (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)
+               for (vma = mm->mmap; vma; vma = vma->vm_next) {
+                       clear_refs_walk.private = vma;
                        if (!is_vm_hugetlb_page(vma))
-                               walk_page_range(mm, vma->vm_start, vma->vm_end,
-                                               &clear_refs_walk, vma);
+                               walk_page_range(vma->vm_start, vma->vm_end,
+                                               &clear_refs_walk);
+               }
                flush_tlb_mm(mm);
                up_read(&mm->mmap_sem);
                mmput(mm);
@@ -528,9 +534,9 @@ static int add_to_pagemap(unsigned long addr, u64 pfn,
 }
 
 static int pagemap_pte_hole(unsigned long start, unsigned long end,
-                               void *private)
+                               struct mm_walk *walk)
 {
-       struct pagemapread *pm = private;
+       struct pagemapread *pm = walk->private;
        unsigned long addr;
        int err = 0;
        for (addr = start; addr < end; addr += PAGE_SIZE) {
@@ -547,24 +553,45 @@ 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,
-                            void *private)
+                            struct mm_walk *walk)
 {
-       struct pagemapread *pm = private;
+       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;
@@ -575,11 +602,6 @@ 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
  *
@@ -614,12 +636,17 @@ 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;
@@ -632,11 +659,15 @@ 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;
 
@@ -657,33 +688,33 @@ 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(mm, start_vaddr, end_vaddr,
-                                       &pagemap_walk, &pm);
-               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--) {
@@ -716,7 +747,7 @@ 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))
+       if (maps_protect && !ptrace_may_access(task, PTRACE_MODE_READ))
                return -EACCES;
 
        return show_numa_map(m, v);