mm: remove nopage

Nothing in the tree uses nopage any more.  Remove support for it in the
core mm code and documentation (and a few stray references to it in
comments).

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

9 files changed, 11 insertions, 43 deletions

diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt
index 448729fcaeb1..599fe55bf297 100644
--- a/Documentation/feature-removal-schedule.txt
+++ b/Documentation/feature-removal-schedule.txt
@@ -128,15 +128,6 @@ Who:	Arjan van de Ven <arjan@linux.intel.com>
 
 ---------------------------
 
-What:   vm_ops.nopage
-When:   Soon, provided in-kernel callers have been converted
-Why:    This interface is replaced by vm_ops.fault, but it has been around
-        forever, is used by a lot of drivers, and doesn't cost much to
-        maintain.
-Who:    Nick Piggin <npiggin@suse.de>
-
----------------------------
-
 What:   PHYSDEVPATH, PHYSDEVBUS, PHYSDEVDRIVER in the uevent environment
 When:   October 2008
 Why:    The stacking of class devices makes these values misleading and
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index 42d4b30b1045..c2992bc54f2f 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -511,7 +511,6 @@ prototypes:
         void (*open)(struct vm_area_struct*);
         void (*close)(struct vm_area_struct*);
         int (*fault)(struct vm_area_struct*, struct vm_fault *);
-        struct page *(*nopage)(struct vm_area_struct*, unsigned long, int *);
         int (*page_mkwrite)(struct vm_area_struct *, struct page *);
 
 locking rules:
@@ -519,7 +518,6 @@ locking rules:
 open:           no      yes
 close:          no      yes
 fault:          no      yes
-nopage:         no      yes
 page_mkwrite:   no      yes             no
 
         ->page_mkwrite() is called when a previously read-only page is
@@ -537,4 +535,3 @@ NULL.
 
 ipc/shm.c::shm_delete() - may need BKL.
 ->read() and ->write() in many drivers are (probably) missing BKL.
-drivers/sgi/char/graphics.c::sgi_graphics_nopage() - may need BKL.
diff --git a/drivers/media/video/vino.c b/drivers/media/video/vino.c
index d545c98dd5e7..01ea99c9bc1a 100644
--- a/drivers/media/video/vino.c
+++ b/drivers/media/video/vino.c
@@ -13,7 +13,7 @@
 /*
  * TODO:
  * - remove "mark pages reserved-hacks" from memory allocation code
- *   and implement nopage()
+ *   and implement fault()
  * - check decimation, calculating and reporting image size when
  *   using decimation
  * - implement read(), user mode buffers and overlay (?)
diff --git a/drivers/video/vermilion/vermilion.c b/drivers/video/vermilion/vermilion.c
index 2aa71eb67c2b..c18f1884b550 100644
--- a/drivers/video/vermilion/vermilion.c
+++ b/drivers/video/vermilion/vermilion.c
@@ -112,8 +112,9 @@ static int vmlfb_alloc_vram_area(struct vram_area *va, unsigned max_order,
 
         /*
          * It seems like __get_free_pages only ups the usage count
-         * of the first page. This doesn't work with nopage mapping, so
-         * up the usage count once more.
+         * of the first page. This doesn't work with fault mapping, so
+         * up the usage count once more (XXX: should use split_page or
+         * compound page).
          */
 
         memset((void *)va->logical, 0x00, va->size);
diff --git a/fs/gfs2/ops_address.c b/fs/gfs2/ops_address.c
index 90a04a6e3789..f55394e57cb2 100644
--- a/fs/gfs2/ops_address.c
+++ b/fs/gfs2/ops_address.c
@@ -438,7 +438,7 @@ static int stuffed_readpage(struct gfs2_inode *ip, struct page *page)
         int error;
 
         /*
-         * Due to the order of unstuffing files and ->nopage(), we can be
+         * Due to the order of unstuffing files and ->fault(), we can be
          * asked for a zero page in the case of a stuffed file being extended,
          * so we need to supply one here. It doesn't happen often.
          */
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 286d31521605..ca973359fe5f 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -164,8 +164,6 @@ struct vm_operations_struct {
         void (*open)(struct vm_area_struct * area);
         void (*close)(struct vm_area_struct * area);
         int (*fault)(struct vm_area_struct *vma, struct vm_fault *vmf);
-        struct page *(*nopage)(struct vm_area_struct *area,
-                        unsigned long address, int *type);
         unsigned long (*nopfn)(struct vm_area_struct *area,
                         unsigned long address);
 
@@ -649,12 +647,6 @@ static inline int page_mapped(struct page *page)
 }
 
 /*
- * Error return values for the *_nopage functions
- */
-#define NOPAGE_SIGBUS   (NULL)
-#define NOPAGE_OOM      ((struct page *) (-1))
-
-/*
  * Error return values for the *_nopfn functions
  */
 #define NOPFN_SIGBUS    ((unsigned long) -1)
diff --git a/mm/memory.c b/mm/memory.c
index 0d14d1e58a5f..46958fb97c2d 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1057,8 +1057,7 @@ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
                 if (pages)
                         foll_flags |= FOLL_GET;
                 if (!write && !(vma->vm_flags & VM_LOCKED) &&
-                    (!vma->vm_ops || (!vma->vm_ops->nopage &&
-                                        !vma->vm_ops->fault)))
+                    (!vma->vm_ops || !vma->vm_ops->fault))
                         foll_flags |= FOLL_ANON;
 
                 do {
@@ -2199,20 +2198,9 @@ static int __do_fault(struct mm_struct *mm, struct vm_area_struct *vma,
 
         BUG_ON(vma->vm_flags & VM_PFNMAP);
 
-        if (likely(vma->vm_ops->fault)) {
-                ret = vma->vm_ops->fault(vma, &vmf);
-                if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE)))
-                        return ret;
-        } else {
-                /* Legacy ->nopage path */
-                ret = 0;
-                vmf.page = vma->vm_ops->nopage(vma, address & PAGE_MASK, &ret);
-                /* no page was available -- either SIGBUS or OOM */
-                if (unlikely(vmf.page == NOPAGE_SIGBUS))
-                        return VM_FAULT_SIGBUS;
-                else if (unlikely(vmf.page == NOPAGE_OOM))
-                        return VM_FAULT_OOM;
-        }
+        ret = vma->vm_ops->fault(vma, &vmf);
+        if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE)))
+                return ret;
 
         /*
          * For consistency in subsequent calls, make the faulted page always
@@ -2458,7 +2446,7 @@ static inline int handle_pte_fault(struct mm_struct *mm,
         if (!pte_present(entry)) {
                 if (pte_none(entry)) {
                         if (vma->vm_ops) {
-                                if (vma->vm_ops->fault || vma->vm_ops->nopage)
+                                if (likely(vma->vm_ops->fault))
                                         return do_linear_fault(mm, vma, address,
                                                 pte, pmd, write_access, entry);
                                 if (unlikely(vma->vm_ops->nopfn))
diff --git a/mm/mincore.c b/mm/mincore.c
index 5efe0ded69b1..5178800bc129 100644
--- a/mm/mincore.c
+++ b/mm/mincore.c
@@ -33,7 +33,7 @@ static unsigned char mincore_page(struct address_space *mapping, pgoff_t pgoff)
          * When tmpfs swaps out a page from a file, any process mapping that
          * file will not get a swp_entry_t in its pte, but rather it is like
          * any other file mapping (ie. marked !present and faulted in with
-         * tmpfs's .nopage). So swapped out tmpfs mappings are tested here.
+         * tmpfs's .fault). So swapped out tmpfs mappings are tested here.
          *
          * However when tmpfs moves the page from pagecache and into swapcache,
          * it is still in core, but the find_get_page below won't find it.
diff --git a/mm/rmap.c b/mm/rmap.c
index e9bb6b1093f6..bf0a5b7cfb8e 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -662,7 +662,6 @@ void page_remove_rmap(struct page *page, struct vm_area_struct *vma)
                         printk (KERN_EMERG "  page->mapping = %p\n", page->mapping);
                         print_symbol (KERN_EMERG "  vma->vm_ops = %s\n", (unsigned long)vma->vm_ops);
                         if (vma->vm_ops) {
-                                print_symbol (KERN_EMERG "  vma->vm_ops->nopage = %s\n", (unsigned long)vma->vm_ops->nopage);
                                 print_symbol (KERN_EMERG "  vma->vm_ops->fault = %s\n", (unsigned long)vma->vm_ops->fault);
                         }
                         if (vma->vm_file && vma->vm_file->f_op)