X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=mm%2Ffilemap_xip.c;h=32132f3cd641a9bdea85c101aebfb51315ee0456;hb=535131e6925b4a95f321148ad7293f496e0e58d7;hp=65ffc321f0c0f223e4c6115e91c53d12d8319399;hpb=64b853aa328f34dd58e4e617cded91e2ddbcac13;p=linux-2.6

diff --git a/mm/filemap_xip.c b/mm/filemap_xip.c
index 65ffc321f0..32132f3cd6 100644
--- a/mm/filemap_xip.c
+++ b/mm/filemap_xip.c
@@ -15,7 +15,6 @@
 #include <linux/rmap.h>
 #include <linux/sched.h>
 #include <asm/tlbflush.h>
-#include "filemap.h"
 
 /*
  * We do use our own empty page to avoid interference with other users
@@ -205,62 +204,58 @@ __xip_unmap (struct address_space * mapping,
 }
 
 /*
- * xip_nopage() is invoked via the vma operations vector for a
+ * xip_fault() is invoked via the vma operations vector for a
  * mapped memory region to read in file data during a page fault.
  *
- * This function is derived from filemap_nopage, but used for execute in place
+ * This function is derived from filemap_fault, but used for execute in place
  */
-static struct page *
-xip_file_nopage(struct vm_area_struct * area,
-		   unsigned long address,
-		   int *type)
+static int xip_file_fault(struct vm_area_struct *area, struct vm_fault *vmf)
 {
 	struct file *file = area->vm_file;
 	struct address_space *mapping = file->f_mapping;
 	struct inode *inode = mapping->host;
 	struct page *page;
-	unsigned long size, pgoff, endoff;
+	pgoff_t size;
 
-	pgoff = ((address - area->vm_start) >> PAGE_CACHE_SHIFT)
-		+ area->vm_pgoff;
-	endoff = ((area->vm_end - area->vm_start) >> PAGE_CACHE_SHIFT)
-		+ area->vm_pgoff;
+	/* XXX: are VM_FAULT_ codes OK? */
 
 	size = (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
-	if (pgoff >= size)
-		return NOPAGE_SIGBUS;
+	if (vmf->pgoff >= size)
+		return VM_FAULT_SIGBUS;
 
-	page = mapping->a_ops->get_xip_page(mapping, pgoff*(PAGE_SIZE/512), 0);
+	page = mapping->a_ops->get_xip_page(mapping,
+					vmf->pgoff*(PAGE_SIZE/512), 0);
 	if (!IS_ERR(page))
 		goto out;
 	if (PTR_ERR(page) != -ENODATA)
-		return NOPAGE_SIGBUS;
+		return VM_FAULT_OOM;
 
 	/* sparse block */
 	if ((area->vm_flags & (VM_WRITE | VM_MAYWRITE)) &&
 	    (area->vm_flags & (VM_SHARED| VM_MAYSHARE)) &&
 	    (!(mapping->host->i_sb->s_flags & MS_RDONLY))) {
 		/* maybe shared writable, allocate new block */
-		page = mapping->a_ops->get_xip_page (mapping,
-			pgoff*(PAGE_SIZE/512), 1);
+		page = mapping->a_ops->get_xip_page(mapping,
+					vmf->pgoff*(PAGE_SIZE/512), 1);
 		if (IS_ERR(page))
-			return NOPAGE_SIGBUS;
+			return VM_FAULT_SIGBUS;
 		/* unmap page at pgoff from all other vmas */
-		__xip_unmap(mapping, pgoff);
+		__xip_unmap(mapping, vmf->pgoff);
 	} else {
 		/* not shared and writable, use xip_sparse_page() */
 		page = xip_sparse_page();
 		if (!page)
-			return NOPAGE_OOM;
+			return VM_FAULT_OOM;
 	}
 
 out:
 	page_cache_get(page);
-	return page;
+	vmf->page = page;
+	return 0;
 }
 
 static struct vm_operations_struct xip_file_vm_ops = {
-	.nopage         = xip_file_nopage,
+	.fault	= xip_file_fault,
 };
 
 int xip_file_mmap(struct file * file, struct vm_area_struct * vma)
@@ -269,6 +264,7 @@ int xip_file_mmap(struct file * file, struct vm_area_struct * vma)
 
 	file_accessed(file);
 	vma->vm_ops = &xip_file_vm_ops;
+	vma->vm_flags |= VM_CAN_NONLINEAR;
 	return 0;
 }
 EXPORT_SYMBOL_GPL(xip_file_mmap);
@@ -291,6 +287,7 @@ __xip_file_write(struct file *filp, const char __user *buf,
 		unsigned long index;
 		unsigned long offset;
 		size_t copied;
+		char *kaddr;
 
 		offset = (pos & (PAGE_CACHE_SIZE -1)); /* Within page */
 		index = pos >> PAGE_CACHE_SHIFT;
@@ -298,14 +295,6 @@ __xip_file_write(struct file *filp, const char __user *buf,
 		if (bytes > count)
 			bytes = count;
 
-		/*
-		 * Bring in the user page that we will copy from _first_.
-		 * Otherwise there's a nasty deadlock on copying from the
-		 * same page as we're writing to, without it being marked
-		 * up-to-date.
-		 */
-		fault_in_pages_readable(buf, bytes);
-
 		page = a_ops->get_xip_page(mapping,
 					   index*(PAGE_SIZE/512), 0);
 		if (IS_ERR(page) && (PTR_ERR(page) == -ENODATA)) {
@@ -322,8 +311,13 @@ __xip_file_write(struct file *filp, const char __user *buf,
 			break;
 		}
 
-		copied = filemap_copy_from_user(page, offset, buf, bytes);
+		fault_in_pages_readable(buf, bytes);
+		kaddr = kmap_atomic(page, KM_USER0);
+		copied = bytes -
+			__copy_from_user_inatomic_nocache(kaddr, buf, bytes);
+		kunmap_atomic(kaddr, KM_USER0);
 		flush_dcache_page(page);
+
 		if (likely(copied > 0)) {
 			status = copied;