(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;
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(¤t->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(¤t->mm->mmap_sem);
+ return buffer;
+}
+
+void free_locked_buffer(void *buffer, size_t size)
+{
+ unsigned long pgsz = PAGE_ALIGN(size) >> PAGE_SHIFT;
+
+ down_write(¤t->mm->mmap_sem);
+
+ current->mm->total_vm -= pgsz;
+ current->mm->locked_vm -= pgsz;
+
+ up_write(¤t->mm->mmap_sem);
+
+ kfree(buffer);
+}