um: embed ->stub_pages[] into mmu_context

seriously, kmalloc() for two-element array of pointers?

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/arch/um/include/asm/mmu.h b/arch/um/include/asm/mmu.h
index 30509b9..53e8b49 100644 (file)
--- a/arch/um/include/asm/mmu.h
+++ b/arch/um/include/asm/mmu.h
@@ -12,7 +12,7 @@
 typedef struct mm_context {
        struct mm_id id;
        struct uml_arch_mm_context arch;
-       struct page **stub_pages;
+       struct page *stub_pages[2];
 } mm_context_t;
 
 extern void __switch_mm(struct mm_id * mm_idp);

diff --git a/arch/um/kernel/skas/mmu.c b/arch/um/kernel/skas/mmu.c
index 1aee587..db2ef42 100644 (file)
--- a/arch/um/kernel/skas/mmu.c
+++ b/arch/um/kernel/skas/mmu.c
@@ -92,8 +92,6 @@ int init_new_context(struct task_struct *task, struct mm_struct *mm)
                goto out_free;
        }
 
-       to_mm->stub_pages = NULL;
-
        return 0;
 
  out_free:
@@ -120,29 +118,20 @@ void arch_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm)
        if (ret)
                goto out;
 
-       pages = kmalloc(2 * sizeof(struct page *), GFP_KERNEL);
-       if (pages == NULL) {
-               printk(KERN_ERR "arch_dup_mmap failed to allocate 2 page "
-                      "pointers\n");
-               goto out;
-       }
-
-       pages[0] = virt_to_page(&__syscall_stub_start);
-       pages[1] = virt_to_page(mm->context.id.stack);
-       mm->context.stub_pages = pages;
+       mm->context.stub_pages[0] = virt_to_page(&__syscall_stub_start);
+       mm->context.stub_pages[1] = virt_to_page(mm->context.id.stack);
 
        /* dup_mmap already holds mmap_sem */
        err = install_special_mapping(mm, STUB_START, STUB_END - STUB_START,
                                      VM_READ | VM_MAYREAD | VM_EXEC |
-                                     VM_MAYEXEC | VM_DONTCOPY, pages);
+                                     VM_MAYEXEC | VM_DONTCOPY,
+                                     mm->context.stub_pages);
        if (err) {
                printk(KERN_ERR "install_special_mapping returned %d\n", err);
-               goto out_free;
+               goto out;
        }
        return;
 
-out_free:
-       kfree(pages);
 out:
        force_sigsegv(SIGSEGV, current);
 }
@@ -151,8 +140,6 @@ void arch_exit_mmap(struct mm_struct *mm)
 {
        pte_t *pte;
 
-       if (mm->context.stub_pages != NULL)
-               kfree(mm->context.stub_pages);
        pte = virt_to_pte(mm, STUB_CODE);
        if (pte != NULL)
                pte_clear(mm, STUB_CODE, pte);