bootmem: print request details before BUG_ON(them)

[mv-sheeva.git] / mm / mlock.c

diff --git a/mm/mlock.c b/mm/mlock.c
index 1ada366570cb535e4a281f7d526829c708f320f3..e125156c664e9a860c9db12d9cc7d712cc4ed016 100644 (file)
--- a/mm/mlock.c
+++ b/mm/mlock.c
@@ -173,12 +173,13 @@ static long __mlock_vma_pages_range(struct vm_area_struct *vma,
                  (atomic_read(&mm->mm_users) != 0));
 
        /*
-        * mlock:   don't page populate if page has PROT_NONE permission.
-        * munlock: the pages always do munlock althrough
-        *          its has PROT_NONE permission.
+        * mlock:   don't page populate if vma has PROT_NONE permission.
+        * munlock: always do munlock although the vma has PROT_NONE
+        *          permission, or SIGKILL is pending.
         */
        if (!mlock)
-               gup_flags |= GUP_FLAGS_IGNORE_VMA_PERMISSIONS;
+               gup_flags |= GUP_FLAGS_IGNORE_VMA_PERMISSIONS |
+                            GUP_FLAGS_IGNORE_SIGKILL;
 
        if (vma->vm_flags & VM_WRITE)
                gup_flags |= GUP_FLAGS_WRITE;
@@ -667,3 +668,48 @@ void user_shm_unlock(size_t size, struct user_struct *user)
        spin_unlock(&shmlock_user_lock);
        free_uid(user);
 }
+
+void *alloc_locked_buffer(size_t size)
+{
+       unsigned long rlim, vm, pgsz;
+       void *buffer = NULL;
+
+       pgsz = PAGE_ALIGN(size) >> PAGE_SHIFT;
+
+       down_write(&current->mm->mmap_sem);
+
+       rlim = current->signal->rlim[RLIMIT_AS].rlim_cur >> PAGE_SHIFT;
+       vm   = current->mm->total_vm + pgsz;
+       if (rlim < vm)
+               goto out;
+
+       rlim = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur >> PAGE_SHIFT;
+       vm   = current->mm->locked_vm + pgsz;
+       if (rlim < vm)
+               goto out;
+
+       buffer = kzalloc(size, GFP_KERNEL);
+       if (!buffer)
+               goto out;
+
+       current->mm->total_vm  += pgsz;
+       current->mm->locked_vm += pgsz;
+
+ out:
+       up_write(&current->mm->mmap_sem);
+       return buffer;
+}
+
+void free_locked_buffer(void *buffer, size_t size)
+{
+       unsigned long pgsz = PAGE_ALIGN(size) >> PAGE_SHIFT;
+
+       down_write(&current->mm->mmap_sem);
+
+       current->mm->total_vm  -= pgsz;
+       current->mm->locked_vm -= pgsz;
+
+       up_write(&current->mm->mmap_sem);
+
+       kfree(buffer);
+}