Large Blocksize Support V6

Index: linux-2.6/drivers/block/loop.c
===================================================================
@@ -251,7 +251,7 @@ static int do_lo_send_aops(struct loop_d
 			 */
 			printk(KERN_ERR "loop: transfer error block %llu\n",
 			       (unsigned long long)index);
-			zero_user_page(page, offset, size, KM_USER0);
+			zero_user(page, offset, size);
 		}
 		flush_dcache_page(page);
 		ret = aops->commit_write(file, page, offset,

120 lines not on this page · raw message

Index: linux-2.6/fs/cifs/inode.c
===================================================================
@@ -1353,7 +1353,7 @@ static int cifs_truncate_page(struct add
 	if (!page)
 		return -ENOMEM;
 
-	zero_user_page(page, offset, PAGE_CACHE_SIZE - offset, KM_USER0);
+	zero_user_segment(page, offset, PAGE_CACHE_SIZE);
 	unlock_page(page);
 	page_cache_release(page);
 	return rc;

Index: linux-2.6/fs/direct-io.c
===================================================================
@@ -887,8 +887,8 @@ do_holes:
 					page_cache_release(page);
 					goto out;
 				}
-				zero_user_page(page, block_in_page << blkbits,
-						1 << blkbits, KM_USER0);
+				zero_user(page, block_in_page << blkbits,
+						1 << blkbits);
 				dio->block_in_file++;
 				block_in_page++;
 				goto next_block;

Index: linux-2.6/fs/ecryptfs/mmap.c
===================================================================
@@ -371,8 +371,7 @@ static int fill_zeros_to_end_of_page(str
 	end_byte_in_page = i_size_read(inode) % PAGE_CACHE_SIZE;
 	if (to > end_byte_in_page)
 		end_byte_in_page = to;
-	zero_user_page(page, end_byte_in_page,
-		PAGE_CACHE_SIZE - end_byte_in_page, KM_USER0);
+	zero_user_segment(page, end_byte_in_page, PAGE_CACHE_SIZE);
 out:
 	return 0;
 }

@@ -422,7 +421,7 @@ static int ecryptfs_prepare_write(struct
 			}
 		}
 		if (end_of_prev_pg_pos + 1 > i_size_read(page->mapping->host))
-			zero_user_page(page, 0, PAGE_CACHE_SIZE, KM_USER0);
+			zero_user(page, 0, PAGE_CACHE_SIZE);
 	}
 out:
 	return rc;

@@ -790,7 +789,7 @@ ecryptfs_write_zeros(struct file *file, 
 		page_cache_release(tmp_page);
 		goto out;
 	}
-	zero_user_page(tmp_page, start, num_zeros, KM_USER0);
+	zero_user(tmp_page, start, num_zeros);
 	rc = ecryptfs_commit_write(file, tmp_page, start, start + num_zeros);
 	if (rc < 0) {
 		ecryptfs_printk(KERN_ERR, "Error attempting to write zero's "

Index: linux-2.6/fs/ext3/inode.c
===================================================================
@@ -1778,7 +1778,7 @@ static int ext3_block_truncate_page(hand
 	 */
 	if (!page_has_buffers(page) && test_opt(inode->i_sb, NOBH) &&
 	     ext3_should_writeback_data(inode) && PageUptodate(page)) {
-		zero_user_page(page, offset, length, KM_USER0);
+		zero_user(page, offset, length);
 		set_page_dirty(page);
 		goto unlock;
 	}

@@ -1831,7 +1831,7 @@ static int ext3_block_truncate_page(hand
 			goto unlock;
 	}
 
-	zero_user_page(page, offset, length, KM_USER0);
+	zero_user(page, offset, length);
 	BUFFER_TRACE(bh, "zeroed end of block");
 
 	err = 0;

Index: linux-2.6/fs/ext4/inode.c
===================================================================
@@ -1777,7 +1777,7 @@ int ext4_block_truncate_page(handle_t *h
 	 */
 	if (!page_has_buffers(page) && test_opt(inode->i_sb, NOBH) &&
 	     ext4_should_writeback_data(inode) && PageUptodate(page)) {
-		zero_user_page(page, offset, length, KM_USER0);
+		zero_user(page, offset, length);
 		set_page_dirty(page);
 		goto unlock;
 	}

@@ -1830,7 +1830,7 @@ int ext4_block_truncate_page(handle_t *h
 			goto unlock;
 	}
 
-	zero_user_page(page, offset, length, KM_USER0);
+	zero_user(page, offset, length);
 
 	BUFFER_TRACE(bh, "zeroed end of block");
 

Index: linux-2.6/fs/gfs2/bmap.c
===================================================================
@@ -933,7 +933,7 @@ static int gfs2_block_truncate_page(stru
 	if (sdp->sd_args.ar_data == GFS2_DATA_ORDERED || gfs2_is_jdata(ip))
 		gfs2_trans_add_bh(ip->i_gl, bh, 0);
 
-	zero_user_page(page, offset, length, KM_USER0);
+	zero_user(page, offset, length);
 
 unlock:
 	unlock_page(page);

Index: linux-2.6/fs/gfs2/ops_address.c
===================================================================
@@ -208,7 +208,7 @@ static int stuffed_readpage(struct gfs2_
 	 * so we need to supply one here. It doesn't happen often.
 	 */
 	if (unlikely(page->index)) {
-		zero_user_page(page, 0, PAGE_CACHE_SIZE, KM_USER0);
+		zero_user(page, 0, PAGE_CACHE_SIZE);
 		return 0;
 	}
 

Index: linux-2.6/fs/libfs.c
===================================================================
@@ -340,13 +340,10 @@ int simple_prepare_write(struct file *fi
 			unsigned from, unsigned to)
 {
 	if (!PageUptodate(page)) {
-		if (to - from != PAGE_CACHE_SIZE) {
-			void *kaddr = kmap_atomic(page, KM_USER0);
-			memset(kaddr, 0, from);
-			memset(kaddr + to, 0, PAGE_CACHE_SIZE - to);
-			flush_dcache_page(page);
-			kunmap_atomic(kaddr, KM_USER0);
-		}
+		if (to - from != PAGE_CACHE_SIZE)
+			zero_user_segments(page,
+				0, from,
+				to, PAGE_CACHE_SIZE);
 	}
 	return 0;
 }

Index: linux-2.6/fs/mpage.c
===================================================================
@@ -284,9 +284,7 @@ do_mpage_readpage(struct bio *bio, struc
 	}
 
 	if (first_hole != blocks_per_page) {
-		zero_user_page(page, first_hole << blkbits,
-				PAGE_CACHE_SIZE - (first_hole << blkbits),
-				KM_USER0);
+		zero_user_segment(page, first_hole << blkbits, PAGE_CACHE_SIZE);
 		if (first_hole == 0) {
 			SetPageUptodate(page);
 			unlock_page(page);

@@ -585,8 +583,7 @@ page_is_mapped:
 
 		if (page->index > end_index || !offset)
 			goto confused;
-		zero_user_page(page, offset, PAGE_CACHE_SIZE - offset,
-				KM_USER0);
+		zero_user_segment(page, offset, PAGE_CACHE_SIZE);
 	}
 
 	/*

Index: linux-2.6/fs/nfs/read.c
===================================================================
@@ -79,7 +79,7 @@ void nfs_readdata_release(void *data)
 static
 int nfs_return_empty_page(struct page *page)
 {
-	zero_user_page(page, 0, PAGE_CACHE_SIZE, KM_USER0);
+	zero_user(page, 0, PAGE_CACHE_SIZE);
 	SetPageUptodate(page);
 	unlock_page(page);
 	return 0;

@@ -103,10 +103,10 @@ static void nfs_readpage_truncate_uninit
 	pglen = PAGE_CACHE_SIZE - base;
 	for (;;) {
 		if (remainder <= pglen) {
-			zero_user_page(*pages, base, remainder, KM_USER0);
+			zero_user(*pages, base, remainder);
 			break;
 		}
-		zero_user_page(*pages, base, pglen, KM_USER0);
+		zero_user(*pages, base, pglen);
 		pages++;
 		remainder -= pglen;
 		pglen = PAGE_CACHE_SIZE;

@@ -130,7 +130,7 @@ static int nfs_readpage_async(struct nfs
 		return PTR_ERR(new);
 	}
 	if (len < PAGE_CACHE_SIZE)
-		zero_user_page(page, len, PAGE_CACHE_SIZE - len, KM_USER0);
+		zero_user_segment(page, len, PAGE_CACHE_SIZE);
 
 	nfs_list_add_request(new, &one_request);
 	if (NFS_SERVER(inode)->rsize < PAGE_CACHE_SIZE)

@@ -538,7 +538,7 @@ readpage_async_filler(void *data, struct
 		goto out_error;
 
 	if (len < PAGE_CACHE_SIZE)
-		zero_user_page(page, len, PAGE_CACHE_SIZE - len, KM_USER0);
+		zero_user_segment(page, len, PAGE_CACHE_SIZE);
 	nfs_pageio_add_request(desc->pgio, new);
 	return 0;
 out_error:

Index: linux-2.6/fs/nfs/write.c
===================================================================
@@ -168,7 +168,7 @@ static void nfs_mark_uptodate(struct pag
 	if (count != nfs_page_length(page))
 		return;
 	if (count != PAGE_CACHE_SIZE)
-		zero_user_page(page, count, PAGE_CACHE_SIZE - count, KM_USER0);
+		zero_user_segment(page, count, PAGE_CACHE_SIZE);
 	SetPageUptodate(page);
 }
 

Index: linux-2.6/fs/ntfs/aops.c
===================================================================
@@ -87,13 +87,17 @@ static void ntfs_end_buffer_async_read(s
 		/* Check for the current buffer head overflowing. */
 		if (unlikely(file_ofs + bh->b_size > init_size)) {
 			int ofs;
+			void *kaddr;
 
 			ofs = 0;
 			if (file_ofs < init_size)
 				ofs = init_size - file_ofs;
 			local_irq_save(flags);
-			zero_user_page(page, bh_offset(bh) + ofs,
-					 bh->b_size - ofs, KM_BIO_SRC_IRQ);
+			kaddr = kmap_atomic(page, KM_BIO_SRC_IRQ);
+			memset(kaddr + bh_offset(bh) + ofs, 0,
+					bh->b_size - ofs);
+			flush_dcache_page(page);
+			kunmap_atomic(kaddr, KM_BIO_SRC_IRQ);
 			local_irq_restore(flags);
 		}
 	} else {

@@ -334,7 +338,7 @@ handle_hole:
 		bh->b_blocknr = -1UL;
 		clear_buffer_mapped(bh);
 handle_zblock:
-		zero_user_page(page, i * blocksize, blocksize, KM_USER0);
+		zero_user(page, i * blocksize, blocksize);
 		if (likely(!err))
 			set_buffer_uptodate(bh);
 	} while (i++, iblock++, (bh = bh->b_this_page) != head);

@@ -451,7 +455,7 @@ retry_readpage:
 	 * ok to ignore the compressed flag here.
 	 */
 	if (unlikely(page->index > 0)) {
-		zero_user_page(page, 0, PAGE_CACHE_SIZE, KM_USER0);
+		zero_user(page, 0, PAGE_CACHE_SIZE);
 		goto done;
 	}
 	if (!NInoAttr(ni))

@@ -780,8 +784,7 @@ lock_retry_remap:
 		if (err == -ENOENT || lcn == LCN_ENOENT) {
 			bh->b_blocknr = -1;
 			clear_buffer_dirty(bh);
-			zero_user_page(page, bh_offset(bh), blocksize,
-					KM_USER0);
+			zero_user(page, bh_offset(bh), blocksize);
 			set_buffer_uptodate(bh);
 			err = 0;
 			continue;

@@ -1406,8 +1409,7 @@ retry_writepage:
 		if (page->index >= (i_size >> PAGE_CACHE_SHIFT)) {
 			/* The page straddles i_size. */
 			unsigned int ofs = i_size & ~PAGE_CACHE_MASK;
-			zero_user_page(page, ofs, PAGE_CACHE_SIZE - ofs,
-					KM_USER0);
+			zero_user_segment(page, ofs, PAGE_CACHE_SIZE);
 		}
 		/* Handle mst protected attributes. */
 		if (NInoMstProtected(ni))

Index: linux-2.6/fs/ntfs/file.c
===================================================================
@@ -607,8 +607,8 @@ do_next_page:
 					ntfs_submit_bh_for_read(bh);
 					*wait_bh++ = bh;
 				} else {
-					zero_user_page(page, bh_offset(bh),
-							blocksize, KM_USER0);
+					zero_user(page, bh_offset(bh),
+							blocksize);
 					set_buffer_uptodate(bh);
 				}
 			}

@@ -683,9 +683,8 @@ map_buffer_cached:
 						ntfs_submit_bh_for_read(bh);
 						*wait_bh++ = bh;
 					} else {
-						zero_user_page(page,
-							bh_offset(bh),
-							blocksize, KM_USER0);
+						zero_user(page, bh_offset(bh),
+								blocksize);
 						set_buffer_uptodate(bh);
 					}
 				}

@@ -703,8 +702,8 @@ map_buffer_cached:
 			 */
 			if (bh_end <= pos || bh_pos >= end) {
 				if (!buffer_uptodate(bh)) {
-					zero_user_page(page, bh_offset(bh),
-							blocksize, KM_USER0);
+					zero_user(page, bh_offset(bh),
+							blocksize);
 					set_buffer_uptodate(bh);
 				}
 				mark_buffer_dirty(bh);

@@ -743,8 +742,7 @@ map_buffer_cached:
 				if (!buffer_uptodate(bh))
 					set_buffer_uptodate(bh);
 			} else if (!buffer_uptodate(bh)) {
-				zero_user_page(page, bh_offset(bh), blocksize,
-						KM_USER0);
+				zero_user(page, bh_offset(bh), blocksize);
 				set_buffer_uptodate(bh);
 			}
 			continue;

@@ -868,8 +866,8 @@ rl_not_mapped_enoent:
 					if (!buffer_uptodate(bh))
 						set_buffer_uptodate(bh);
 				} else if (!buffer_uptodate(bh)) {
-					zero_user_page(page, bh_offset(bh),
-							blocksize, KM_USER0);
+					zero_user(page, bh_offset(bh),
+						blocksize);
 					set_buffer_uptodate(bh);
 				}
 				continue;

@@ -1128,8 +1126,8 @@ rl_not_mapped_enoent:
 
 				if (likely(bh_pos < initialized_size))
 					ofs = initialized_size - bh_pos;
-				zero_user_page(page, bh_offset(bh) + ofs,
-						blocksize - ofs, KM_USER0);
+				zero_user_segment(page, bh_offset(bh) + ofs,
+						blocksize);
 			}
 		} else /* if (unlikely(!buffer_uptodate(bh))) */
 			err = -EIO;

@@ -1269,8 +1267,8 @@ rl_not_mapped_enoent:
 				if (PageUptodate(page))
 					set_buffer_uptodate(bh);
 				else {
-					zero_user_page(page, bh_offset(bh),
-							blocksize, KM_USER0);
+					zero_user(page, bh_offset(bh),
+							blocksize);
 					set_buffer_uptodate(bh);
 				}
 			}

@@ -1330,7 +1328,7 @@ err_out:
 		len = PAGE_CACHE_SIZE;
 		if (len > bytes)
 			len = bytes;
-		zero_user_page(*pages, 0, len, KM_USER0);
+		zero_user(*pages, 0, len);
 	}
 	goto out;
 }

@@ -1451,7 +1449,7 @@ err_out:
 		len = PAGE_CACHE_SIZE;
 		if (len > bytes)
 			len = bytes;
-		zero_user_page(*pages, 0, len, KM_USER0);
+		zero_user(*pages, 0, len);
 	}
 	goto out;
 }

Index: linux-2.6/fs/ocfs2/aops.c
===================================================================
@@ -238,7 +238,7 @@ static int ocfs2_readpage(struct file *f
 	 * XXX sys_readahead() seems to get that wrong?
 	 */
 	if (start >= i_size_read(inode)) {
-		zero_user_page(page, 0, PAGE_SIZE, KM_USER0);
+		zero_user(page, 0, PAGE_SIZE);
 		SetPageUptodate(page);
 		ret = 0;
 		goto out_alloc;

@@ -746,7 +746,7 @@ int ocfs2_map_page_blocks(struct page *p
 		if (block_start >= to)
 			break;
 
-		zero_user_page(page, block_start, bh->b_size, KM_USER0);
+		zero_user(page, block_start, bh->b_size);
 		set_buffer_uptodate(bh);
 		mark_buffer_dirty(bh);
 

@@ -905,7 +905,7 @@ static void ocfs2_zero_new_buffers(struc
 					start = max(from, block_start);
 					end = min(to, block_end);
 
-					zero_user_page(page, start, end - start, KM_USER0);
+					zero_user_segment(page, start, end);
 					set_buffer_uptodate(bh);
 				}
 

Index: linux-2.6/fs/reiserfs/inode.c
===================================================================
@@ -2150,7 +2150,7 @@ int reiserfs_truncate_file(struct inode 
 		/* if we are not on a block boundary */
 		if (length) {
 			length = blocksize - length;
-			zero_user_page(page, offset, length, KM_USER0);
+			zero_user(page, offset, length);
 			if (buffer_mapped(bh) && bh->b_blocknr != 0) {
 				mark_buffer_dirty(bh);
 			}

@@ -2374,7 +2374,7 @@ static int reiserfs_write_full_page(stru
 			unlock_page(page);
 			return 0;
 		}
-		zero_user_page(page, last_offset, PAGE_CACHE_SIZE - last_offset, KM_USER0);
+		zero_user_segment(page, last_offset, PAGE_CACHE_SIZE);
 	}
 	bh = head;
 	block = page->index << (PAGE_CACHE_SHIFT - s->s_blocksize_bits);

Index: linux-2.6/fs/xfs/linux-2.6/xfs_lrw.c
===================================================================
@@ -159,7 +159,7 @@ xfs_iozero(
 		if (status)
 			goto unlock;
 
-		zero_user_page(page, offset, bytes, KM_USER0);
+		zero_user(page, offset, bytes);
 
 		status = mapping->a_ops->commit_write(NULL, page, offset,
 							offset + bytes);

59 lines not on this page · raw message

Index: linux-2.6/mm/filemap_xip.c
===================================================================
@@ -433,7 +433,7 @@ xip_truncate_page(struct address_space *
 		else
 			return PTR_ERR(page);
 	}
-	zero_user_page(page, offset, length, KM_USER0);
+	zero_user(page, offset, length);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(xip_truncate_page);

Index: linux-2.6/mm/truncate.c
===================================================================
@@ -47,7 +47,7 @@ void do_invalidatepage(struct page *page
 
 static inline void truncate_partial_page(struct page *page, unsigned partial)
 {
-	zero_user_page(page, partial, PAGE_CACHE_SIZE - partial, KM_USER0);
+	zero_user_segment(page, partial, PAGE_CACHE_SIZE);
 	if (PagePrivate(page))
 		do_invalidatepage(page, partial);
 }

Index: linux-2.6/fs/affs/file.c
===================================================================
@@ -628,7 +628,7 @@ static int affs_prepare_write_ofs(struct
 			return err;
 	}
 	if (to < PAGE_CACHE_SIZE) {
-		zero_user_page(page, to, PAGE_CACHE_SIZE - to, KM_USER0);
+		zero_user_segment(page, to, PAGE_CACHE_SIZE);
 		if (size > offset + to) {
 			if (size < offset + PAGE_CACHE_SIZE)
 				tmp = size & ~PAGE_CACHE_MASK;

Index: linux-2.6/fs/reiserfs/file.c
===================================================================
@@ -1060,11 +1060,11 @@ static int reiserfs_prepare_file_region_
 	   parts of first and last pages in write area (if needed) */
 	if ((pos & ~((loff_t) PAGE_CACHE_SIZE - 1)) > inode->i_size) {
 		if (from != 0)		/* First page needs to be partially zeroed */
-			zero_user_page(prepared_pages[0], 0, from, KM_USER0);
+			zero_user(prepared_pages[0], 0, from);
 
 		if (to != PAGE_CACHE_SIZE)	/* Last page needs to be partially zeroed */
-			zero_user_page(prepared_pages[num_pages-1], to,
-					PAGE_CACHE_SIZE - to, KM_USER0);
+			zero_user_segment(prepared_pages[num_pages-1], to,
+					PAGE_CACHE_SIZE);
 
 		/* Since all blocks are new - use already calculated value */
 		return blocks;

@@ -1191,9 +1191,8 @@ static int reiserfs_prepare_file_region_
 					ll_rw_block(READ, 1, &bh);
 					*wait_bh++ = bh;
 				} else {	/* Not mapped, zero it */
-					zero_user_page(prepared_pages[0],
-						       block_start,
-						       from - block_start, KM_USER0);
+					zero_user_segment(prepared_pages[0],
+						       block_start, from);
 					set_buffer_uptodate(bh);
 				}
 			}

@@ -1225,8 +1224,8 @@ static int reiserfs_prepare_file_region_
 					ll_rw_block(READ, 1, &bh);
 					*wait_bh++ = bh;
 				} else {	/* Not mapped, zero it */
-					zero_user_page(prepared_pages[num_pages-1],
-							to, block_end - to, KM_USER0);
+					zero_user_segment(prepared_pages[num_pages-1],
+							to, block_end);
 					set_buffer_uptodate(bh);
 				}
 			}

index 8a83537..836e9dd 100644
@@ -52,12 +52,66 @@ static inline void mapping_set_gfp_mask(struct address_space *m, gfp_t mask)
  * space in smaller chunks for same flexibility).
  *
  * Or rather, it _will_ be done in larger chunks.
+ *
+ * The following constants can be used if a filesystem only supports a single
+ * page size.
  */
 #define PAGE_CACHE_SHIFT	PAGE_SHIFT
 #define PAGE_CACHE_SIZE		PAGE_SIZE
 #define PAGE_CACHE_MASK		PAGE_MASK
 #define PAGE_CACHE_ALIGN(addr)	(((addr)+PAGE_CACHE_SIZE-1)&PAGE_CACHE_MASK)
 
+/*
+ * Functions that are currently setup for a fixed PAGE_SIZEd. The use of
+ * these will allow a variable page size pagecache in the future.
+ */
+static inline int mapping_order(struct address_space *a)
+{
+	return 0;
+}
+
+static inline int page_cache_shift(struct address_space *a)
+{
+	return PAGE_SHIFT;
+}
+
+static inline unsigned int page_cache_size(struct address_space *a)
+{
+	return PAGE_SIZE;
+}
+
+static inline loff_t page_cache_mask(struct address_space *a)
+{
+	return (loff_t)PAGE_MASK;
+}
+
+static inline unsigned int page_cache_offset(struct address_space *a,
+		loff_t pos)
+{
+	return pos & ~PAGE_MASK;
+}
+
+static inline pgoff_t page_cache_index(struct address_space *a,
+		loff_t pos)
+{
+	return pos >> page_cache_shift(a);
+}
+
+/*
+ * Index of the page starting on or after the given position.
+ */
+static inline pgoff_t page_cache_next(struct address_space *a,
+		loff_t pos)
+{
+	return page_cache_index(a, pos + page_cache_size(a) - 1);
+}
+
+static inline loff_t page_cache_pos(struct address_space *a,
+		pgoff_t index, unsigned long offset)
+{
+	return ((loff_t)index << page_cache_shift(a)) + offset;
+}
+
 #define page_cache_get(page)		get_page(page)
 #define page_cache_release(page)	put_page(page)
 void release_pages(struct page **pages, int nr, int cold);

Index: linux-2.6/mm/filemap.c
===================================================================
@@ -303,8 +303,8 @@ int wait_on_page_writeback_range(struct 
 int sync_page_range(struct inode *inode, struct address_space *mapping,
 			loff_t pos, loff_t count)
 {
-	pgoff_t start = pos >> PAGE_CACHE_SHIFT;
-	pgoff_t end = (pos + count - 1) >> PAGE_CACHE_SHIFT;
+	pgoff_t start = page_cache_index(mapping, pos);
+	pgoff_t end = page_cache_index(mapping, pos + count - 1);
 	int ret;
 
 	if (!mapping_cap_writeback_dirty(mapping) || !count)

@@ -335,8 +335,8 @@ EXPORT_SYMBOL(sync_page_range);
 int sync_page_range_nolock(struct inode *inode, struct address_space *mapping,
 			   loff_t pos, loff_t count)
 {
-	pgoff_t start = pos >> PAGE_CACHE_SHIFT;
-	pgoff_t end = (pos + count - 1) >> PAGE_CACHE_SHIFT;
+	pgoff_t start = page_cache_index(mapping, pos);
+	pgoff_t end = page_cache_index(mapping, pos + count - 1);
 	int ret;
 
 	if (!mapping_cap_writeback_dirty(mapping) || !count)

@@ -365,7 +365,7 @@ int filemap_fdatawait(struct address_spa
 		return 0;
 
 	return wait_on_page_writeback_range(mapping, 0,
-				(i_size - 1) >> PAGE_CACHE_SHIFT);
+				page_cache_index(mapping, i_size - 1));
 }
 EXPORT_SYMBOL(filemap_fdatawait);
 

@@ -413,8 +413,8 @@ int filemap_write_and_wait_range(struct 
 		/* See comment of filemap_write_and_wait() */
 		if (err != -EIO) {
 			int err2 = wait_on_page_writeback_range(mapping,
-						lstart >> PAGE_CACHE_SHIFT,
-						lend >> PAGE_CACHE_SHIFT);
+					page_cache_index(mapping, lstart),
+					page_cache_index(mapping, lend));
 			if (!err)
 				err = err2;
 		}

@@ -877,12 +877,12 @@ void do_generic_mapping_read(struct addr
 	struct file_ra_state ra = *_ra;
 
 	cached_page = NULL;
-	index = *ppos >> PAGE_CACHE_SHIFT;
+	index = page_cache_index(mapping, *ppos);
 	next_index = index;
 	prev_index = ra.prev_index;
 	prev_offset = ra.prev_offset;
-	last_index = (*ppos + desc->count + PAGE_CACHE_SIZE-1) >> PAGE_CACHE_SHIFT;
-	offset = *ppos & ~PAGE_CACHE_MASK;
+	last_index = page_cache_next(mapping, *ppos + desc->count);
+	offset = page_cache_offset(mapping, *ppos);
 
 	for (;;) {
 		struct page *page;

@@ -919,16 +919,16 @@ page_ok:
 		 */
 
 		isize = i_size_read(inode);
-		end_index = (isize - 1) >> PAGE_CACHE_SHIFT;
+		end_index = page_cache_index(mapping, isize - 1);
 		if (unlikely(!isize || index > end_index)) {
 			page_cache_release(page);
 			goto out;
 		}
 
 		/* nr is the maximum number of bytes to copy from this page */
-		nr = PAGE_CACHE_SIZE;
+		nr = page_cache_size(mapping);
 		if (index == end_index) {
-			nr = ((isize - 1) & ~PAGE_CACHE_MASK) + 1;
+			nr = page_cache_offset(mapping, isize - 1) + 1;
 			if (nr <= offset) {
 				page_cache_release(page);
 				goto out;

@@ -963,8 +963,8 @@ page_ok:
 		 */
 		ret = actor(desc, page, offset, nr);
 		offset += ret;
-		index += offset >> PAGE_CACHE_SHIFT;
-		offset &= ~PAGE_CACHE_MASK;
+		index += page_cache_index(mapping, offset);
+		offset = page_cache_offset(mapping, offset);
 		prev_offset = offset;
 		ra.prev_offset = offset;
 

@@ -1058,7 +1058,7 @@ out:
 	*_ra = ra;
 	_ra->prev_index = prev_index;
 
-	*ppos = ((loff_t) index << PAGE_CACHE_SHIFT) + offset;
+	*ppos = page_cache_pos(mapping, index, offset);
 	if (cached_page)
 		page_cache_release(cached_page);
 	if (filp)

@@ -1240,8 +1240,8 @@ asmlinkage ssize_t sys_readahead(int fd,
 	if (file) {
 		if (file->f_mode & FMODE_READ) {
 			struct address_space *mapping = file->f_mapping;
-			unsigned long start = offset >> PAGE_CACHE_SHIFT;
-			unsigned long end = (offset + count - 1) >> PAGE_CACHE_SHIFT;
+			unsigned long start = page_cache_index(mapping, offset);
+			unsigned long end = page_cache_index(mapping, offset + count - 1);
 			unsigned long len = end - start + 1;
 			ret = do_readahead(mapping, file, start, len);
 		}

@@ -1310,7 +1310,7 @@ int filemap_fault(struct vm_area_struct 
 	int did_readaround = 0;
 	int ret = 0;
 
-	size = (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+	size = page_cache_next(mapping, i_size_read(inode));
 	if (vmf->pgoff >= size)
 		goto outside_data_content;
 

@@ -1385,7 +1385,7 @@ retry_find:
 		goto page_not_uptodate;
 
 	/* Must recheck i_size under page lock */
-	size = (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+	size = page_cache_next(mapping, i_size_read(inode));
 	if (unlikely(vmf->pgoff >= size)) {
 		unlock_page(page);
 		goto outside_data_content;

@@ -1869,9 +1869,9 @@ generic_file_buffered_write(struct kiocb
 		unsigned long offset;
 		size_t copied;
 
-		offset = (pos & (PAGE_CACHE_SIZE -1)); /* Within page */
-		index = pos >> PAGE_CACHE_SHIFT;
-		bytes = PAGE_CACHE_SIZE - offset;
+		offset = page_cache_offset(mapping, pos); /* Within page */
+		index = page_cache_index(mapping, pos);
+		bytes = page_cache_size(mapping) - offset;
 
 		/* Limit the size of the copy to the caller's write size */
 		bytes = min(bytes, count);

@@ -2082,8 +2082,8 @@ __generic_file_aio_write_nolock(struct k
 		if (err == 0) {
 			written = written_buffered;
 			invalidate_mapping_pages(mapping,
-						 pos >> PAGE_CACHE_SHIFT,
-						 endbyte >> PAGE_CACHE_SHIFT);
+						 page_cache_index(mapping, pos),
+						 page_cache_index(mapping, endbyte));
 		} else {
 			/*
 			 * We don't know how much we wrote, so just return

@@ -2170,7 +2170,7 @@ generic_file_direct_IO(int rw, struct ki
 	 */
 	if (rw == WRITE) {
 		write_len = iov_length(iov, nr_segs);
-		end = (offset + write_len - 1) >> PAGE_CACHE_SHIFT;
+		end = page_cache_index(mapping, offset + write_len - 1);
 	       	if (mapping_mapped(mapping))
 			unmap_mapping_range(mapping, offset, write_len, 0);
 	}

@@ -2187,7 +2187,7 @@ generic_file_direct_IO(int rw, struct ki
 	 */
 	if (rw == WRITE && mapping->nrpages) {
 		retval = invalidate_inode_pages2_range(mapping,
-					offset >> PAGE_CACHE_SHIFT, end);
+					page_cache_index(mapping, offset), end);
 		if (retval)
 			goto out;
 	}

@@ -2205,7 +2205,7 @@ generic_file_direct_IO(int rw, struct ki
 	 */
 	if (rw == WRITE && mapping->nrpages) {
 		int err = invalidate_inode_pages2_range(mapping,
-					      offset >> PAGE_CACHE_SHIFT, end);
+					      page_cache_index(mapping, offset), end);
 		if (err && retval >= 0)
 			retval = err;
 	}

index 63512a9..ebe76e3 100644
@@ -624,8 +624,8 @@ int write_cache_pages(struct address_space *mapping,
 		index = mapping->writeback_index; /* Start from prev offset */
 		end = -1;
 	} else {
-		index = wbc->range_start >> PAGE_CACHE_SHIFT;
-		end = wbc->range_end >> PAGE_CACHE_SHIFT;
+		index = page_cache_index(mapping, wbc->range_start);
+		end = page_cache_index(mapping, wbc->range_end);
 		if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
 			range_whole = 1;
 		scanned = 1;

@@ -827,7 +827,7 @@ int __set_page_dirty_nobuffers(struct page *page)
 			WARN_ON_ONCE(!PagePrivate(page) && !PageUptodate(page));
 			if (mapping_cap_account_dirty(mapping)) {
 				__inc_zone_page_state(page, NR_FILE_DIRTY);
-				task_io_account_write(PAGE_CACHE_SIZE);
+				task_io_account_write(page_cache_size(mapping));
 			}
 			radix_tree_tag_set(&mapping->page_tree,
 				page_index(page), PAGECACHE_TAG_DIRTY);

index bf8068d..8c3d32e 100644
@@ -45,9 +45,10 @@ void do_invalidatepage(struct page *page, unsigned long offset)
 		(*invalidatepage)(page, offset);
 }
 
-static inline void truncate_partial_page(struct page *page, unsigned partial)
+static inline void truncate_partial_page(struct address_space *mapping,
+			struct page *page, unsigned partial)
 {
-	zero_user_segment(page, partial, PAGE_CACHE_SIZE);
+	zero_user_segment(page, partial, page_cache_size(mapping));
 	if (PagePrivate(page))
 		do_invalidatepage(page, partial);
 }

@@ -95,7 +96,7 @@ truncate_complete_page(struct address_space *mapping, struct page *page)
 	if (page->mapping != mapping)
 		return;
 
-	cancel_dirty_page(page, PAGE_CACHE_SIZE);
+	cancel_dirty_page(page, page_cache_size(mapping));
 
 	if (PagePrivate(page))
 		do_invalidatepage(page, 0);

@@ -157,9 +158,9 @@ invalidate_complete_page(struct address_space *mapping, struct page *page)
 void truncate_inode_pages_range(struct address_space *mapping,
 				loff_t lstart, loff_t lend)
 {
-	const pgoff_t start = (lstart + PAGE_CACHE_SIZE-1) >> PAGE_CACHE_SHIFT;
+	const pgoff_t start = page_cache_next(mapping, lstart);
 	pgoff_t end;
-	const unsigned partial = lstart & (PAGE_CACHE_SIZE - 1);
+	const unsigned partial = page_cache_offset(mapping, lstart);
 	struct pagevec pvec;
 	pgoff_t next;
 	int i;

@@ -167,8 +168,9 @@ void truncate_inode_pages_range(struct address_space *mapping,
 	if (mapping->nrpages == 0)
 		return;
 
-	BUG_ON((lend & (PAGE_CACHE_SIZE - 1)) != (PAGE_CACHE_SIZE - 1));
-	end = (lend >> PAGE_CACHE_SHIFT);
+	BUG_ON(page_cache_offset(mapping, lend) !=
+				page_cache_size(mapping) - 1);
+	end = page_cache_index(mapping, lend);
 
 	pagevec_init(&pvec, 0);
 	next = start;

@@ -194,8 +196,8 @@ void truncate_inode_pages_range(struct address_space *mapping,
 			}
 			if (page_mapped(page)) {
 				unmap_mapping_range(mapping,
-				  (loff_t)page_index<<PAGE_CACHE_SHIFT,
-				  PAGE_CACHE_SIZE, 0);
+				  page_cache_pos(mapping, page_index, 0),
+				  page_cache_size(mapping), 0);
 			}
 			truncate_complete_page(mapping, page);
 			unlock_page(page);

@@ -208,7 +210,7 @@ void truncate_inode_pages_range(struct address_space *mapping,
 		struct page *page = find_lock_page(mapping, start - 1);
 		if (page) {
 			wait_on_page_writeback(page);
-			truncate_partial_page(page, partial);
+			truncate_partial_page(mapping, page, partial);
 			unlock_page(page);
 			page_cache_release(page);
 		}

@@ -236,8 +238,8 @@ void truncate_inode_pages_range(struct address_space *mapping,
 			wait_on_page_writeback(page);
 			if (page_mapped(page)) {
 				unmap_mapping_range(mapping,
-				  (loff_t)page->index<<PAGE_CACHE_SHIFT,
-				  PAGE_CACHE_SIZE, 0);
+				  page_cache_pos(mapping, page->index, 0),
+				  page_cache_size(mapping), 0);
 			}
 			if (page->index > next)
 				next = page->index;

@@ -421,9 +423,8 @@ int invalidate_inode_pages2_range(struct address_space *mapping,
 					 * Zap the rest of the file in one hit.
 					 */
 					unmap_mapping_range(mapping,
-					   (loff_t)page_index<<PAGE_CACHE_SHIFT,
-					   (loff_t)(end - page_index + 1)
-							<< PAGE_CACHE_SHIFT,
+					   page_cache_pos(mapping, page_index, 0),
+					   page_cache_pos(mapping, end - page_index + 1, 0),
 					    0);
 					did_range_unmap = 1;
 				} else {

@@ -431,8 +432,8 @@ int invalidate_inode_pages2_range(struct address_space *mapping,
 					 * Just zap this page
 					 */
 					unmap_mapping_range(mapping,
-					  (loff_t)page_index<<PAGE_CACHE_SHIFT,
-					  PAGE_CACHE_SIZE, 0);
+					  page_cache_pos(mapping, page_index, 0),
+					  page_cache_size(mapping), 0);
 				}
 			}
 			BUG_ON(page_mapped(page));

index 41ac397..d6a1771 100644
@@ -188,9 +188,14 @@ static void page_unlock_anon_vma(struct anon_vma *anon_vma)
 static inline unsigned long
 vma_address(struct page *page, struct vm_area_struct *vma)
 {
-	pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
+	pgoff_t pgoff;
 	unsigned long address;
 
+	if (PageAnon(page))
+		pgoff = page->index;
+	else
+		pgoff = page->index << mapping_order(page->mapping);
+
 	address = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
 	if (unlikely(address < vma->vm_start || address >= vma->vm_end)) {
 		/* page should be within any vma from prio_tree_next */

@@ -335,7 +340,7 @@ static int page_referenced_file(struct page *page)
 {
 	unsigned int mapcount;
 	struct address_space *mapping = page->mapping;
-	pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
+	pgoff_t pgoff = page->index << (page_cache_shift(mapping) - PAGE_SHIFT);
 	struct vm_area_struct *vma;
 	struct prio_tree_iter iter;
 	int referenced = 0;

@@ -447,7 +452,7 @@ out:
 
 static int page_mkclean_file(struct address_space *mapping, struct page *page)
 {
-	pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
+	pgoff_t pgoff = page->index << (page_cache_shift(mapping) - PAGE_SHIFT);
 	struct vm_area_struct *vma;
 	struct prio_tree_iter iter;
 	int ret = 0;

@@ -863,7 +868,7 @@ static int try_to_unmap_anon(struct page *page, int migration)
 static int try_to_unmap_file(struct page *page, int migration)
 {
 	struct address_space *mapping = page->mapping;
-	pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
+	pgoff_t pgoff = page->index << (page_cache_shift(mapping) - PAGE_SHIFT);
 	struct vm_area_struct *vma;
 	struct prio_tree_iter iter;
 	int ret = SWAP_AGAIN;

index ba6892d..5237e53 100644
@@ -61,24 +61,24 @@ do_xip_mapping_read(struct address_space *mapping,
 
 	BUG_ON(!mapping->a_ops->get_xip_page);
 
-	index = *ppos >> PAGE_CACHE_SHIFT;
-	offset = *ppos & ~PAGE_CACHE_MASK;
+	index = page_cache_index(mapping, *ppos);
+	offset = page_cache_offset(mapping, *ppos);
 
 	isize = i_size_read(inode);
 	if (!isize)
 		goto out;
 
-	end_index = (isize - 1) >> PAGE_CACHE_SHIFT;
+	end_index = page_cache_index(mapping, isize - 1);
 	for (;;) {
 		struct page *page;
 		unsigned long nr, ret;
 
 		/* nr is the maximum number of bytes to copy from this page */
-		nr = PAGE_CACHE_SIZE;
+		nr = page_cache_size(mapping);
 		if (index >= end_index) {
 			if (index > end_index)
 				goto out;
-			nr = ((isize - 1) & ~PAGE_CACHE_MASK) + 1;
+			nr = page_cache_next(mapping, size - 1) + 1;
 			if (nr <= offset) {
 				goto out;
 			}

@@ -117,8 +117,8 @@ do_xip_mapping_read(struct address_space *mapping,
 		 */
 		ret = actor(desc, page, offset, nr);
 		offset += ret;
-		index += offset >> PAGE_CACHE_SHIFT;
-		offset &= ~PAGE_CACHE_MASK;
+		index += page_cache_index(mapping, offset);
+		offset = page_cache_offset(mapping, offset);
 
 		if (ret == nr && desc->count)
 			continue;

@@ -131,7 +131,7 @@ no_xip_page:
 	}
 
 out:
-	*ppos = ((loff_t) index << PAGE_CACHE_SHIFT) + offset;
+	*ppos = page_cache_pos(mapping, index, offset);
 	if (filp)
 		file_accessed(filp);
 }

@@ -220,7 +220,7 @@ static int xip_file_fault(struct vm_area_struct *area, struct vm_fault *vmf)
 
 	/* XXX: are VM_FAULT_ codes OK? */
 
-	size = (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+	size = page_cache_next(mapping, i_size_read(inode));
 	if (vmf->pgoff >= size)
 		return VM_FAULT_SIGBUS;
 

@@ -289,9 +289,9 @@ __xip_file_write(struct file *filp, const char __user *buf,
 		unsigned long offset;
 		size_t copied;
 
-		offset = (pos & (PAGE_CACHE_SIZE -1)); /* Within page */
-		index = pos >> PAGE_CACHE_SHIFT;
-		bytes = PAGE_CACHE_SIZE - offset;
+		offset = page_cache_offset(mapping, pos); /* Within page */
+		index = page_cache_index(mapping, pos);
+		bytes = page_cache_size(mapping) - offset;
 		if (bytes > count)
 			bytes = count;
 

@@ -405,8 +405,8 @@ EXPORT_SYMBOL_GPL(xip_file_write);
 int
 xip_truncate_page(struct address_space *mapping, loff_t from)
 {
-	pgoff_t index = from >> PAGE_CACHE_SHIFT;
-	unsigned offset = from & (PAGE_CACHE_SIZE-1);
+	pgoff_t index = page_cache_index(mapping, from);
+	unsigned offset = page_cache_offset(mapping, from);
 	unsigned blocksize;
 	unsigned length;
 	struct page *page;

index 37c73b9..4949927 100644
@@ -195,7 +195,7 @@ static void remove_file_migration_ptes(struct page *old, struct page *new)
 	struct vm_area_struct *vma;
 	struct address_space *mapping = page_mapping(new);
 	struct prio_tree_iter iter;
-	pgoff_t pgoff = new->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
+	pgoff_t pgoff = new->index << mapping_order(mapping);
 
 	if (!mapping)
 		return;

index 53b3dc5..e90f894 100644
@@ -16,7 +16,8 @@ int simple_getattr(struct vfsmount *mnt, struct dentry *dentry,
 {
 	struct inode *inode = dentry->d_inode;
 	generic_fillattr(inode, stat);
-	stat->blocks = inode->i_mapping->nrpages << (PAGE_CACHE_SHIFT - 9);
+	stat->blocks = inode->i_mapping->nrpages <<
+				(page_cache_shift(inode->i_mapping) - 9);
 	return 0;
 }
 

@@ -340,10 +341,10 @@ int simple_prepare_write(struct file *file, struct page *page,
 			unsigned from, unsigned to)
 {
 	if (!PageUptodate(page)) {
-		if (to - from != PAGE_CACHE_SIZE)
+		if (to - from != page_cache_size(file->f_mapping))
 			zero_user_segments(page,
 				0, from,
-				to, PAGE_CACHE_SIZE);
+				to, page_cache_size(file->f_mapping));
 	}
 	return 0;
 }

@@ -351,8 +352,9 @@ int simple_prepare_write(struct file *file, struct page *page,
 int simple_commit_write(struct file *file, struct page *page,
 			unsigned from, unsigned to)
 {
-	struct inode *inode = page->mapping->host;
-	loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
+	struct address_space *mapping = page->mapping;
+	struct inode *inode = mapping->host;
+	loff_t pos = page_cache_pos(mapping, page->index, to);
 
 	if (!PageUptodate(page))
 		SetPageUptodate(page);

index 7cd005e..f30d7eb 100644
@@ -260,8 +260,8 @@ int do_sync_mapping_range(struct address_space *mapping, loff_t offset,
 	ret = 0;
 	if (flags & SYNC_FILE_RANGE_WAIT_BEFORE) {
 		ret = wait_on_page_writeback_range(mapping,
-					offset >> PAGE_CACHE_SHIFT,
-					endbyte >> PAGE_CACHE_SHIFT);
+					page_cache_index(mapping, offset),
+					page_cache_index(mapping, endbyte));
 		if (ret < 0)
 			goto out;
 	}

@@ -275,8 +275,8 @@ int do_sync_mapping_range(struct address_space *mapping, loff_t offset,
 
 	if (flags & SYNC_FILE_RANGE_WAIT_AFTER) {
 		ret = wait_on_page_writeback_range(mapping,
-					offset >> PAGE_CACHE_SHIFT,
-					endbyte >> PAGE_CACHE_SHIFT);
+					page_cache_index(mapping, offset),
+					page_cache_index(mapping, endbyte));
 	}
 out:
 	return ret;

Index: linux-2.6/fs/buffer.c
===================================================================
@@ -257,7 +257,7 @@ __find_get_block_slow(struct block_devic
 	struct page *page;
 	int all_mapped = 1;
 
-	index = block >> (PAGE_CACHE_SHIFT - bd_inode->i_blkbits);
+	index = block >> (page_cache_shift(bd_mapping) - bd_inode->i_blkbits);
 	page = find_get_page(bd_mapping, index);
 	if (!page)
 		goto out;

@@ -697,7 +697,7 @@ static int __set_page_dirty(struct page 
 
 		if (mapping_cap_account_dirty(mapping)) {
 			__inc_zone_page_state(page, NR_FILE_DIRTY);
-			task_io_account_write(PAGE_CACHE_SIZE);
+			task_io_account_write(page_cache_size(mapping));
 		}
 		radix_tree_tag_set(&mapping->page_tree,
 				page_index(page), PAGECACHE_TAG_DIRTY);

@@ -891,10 +891,11 @@ struct buffer_head *alloc_page_buffers(s
 {
 	struct buffer_head *bh, *head;
 	long offset;
+	unsigned int page_size = page_cache_size(page->mapping);
 
 try_again:
 	head = NULL;
-	offset = PAGE_SIZE;
+	offset = page_size;
 	while ((offset -= size) >= 0) {
 		bh = alloc_buffer_head(GFP_NOFS);
 		if (!bh)

@@ -1426,7 +1427,7 @@ void set_bh_page(struct buffer_head *bh,
 		struct page *page, unsigned long offset)
 {
 	bh->b_page = page;
-	BUG_ON(offset >= PAGE_SIZE);
+	BUG_ON(offset >= compound_size(page));
 	if (PageHighMem(page))
 		/*
 		 * This catches illegal uses and preserves the offset:

@@ -1605,6 +1606,7 @@ static int __block_write_full_page(struc
 	struct buffer_head *bh, *head;
 	const unsigned blocksize = 1 << inode->i_blkbits;
 	int nr_underway = 0;
+	struct address_space *mapping = inode->i_mapping;
 
 	BUG_ON(!PageLocked(page));
 

@@ -1625,7 +1627,8 @@ static int __block_write_full_page(struc
 	 * handle that here by just cleaning them.
 	 */
 
-	block = (sector_t)page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
+	block = (sector_t)page->index <<
+		(page_cache_shift(mapping) - inode->i_blkbits);
 	head = page_buffers(page);
 	bh = head;
 

@@ -1742,7 +1745,7 @@ recover:
 	} while ((bh = bh->b_this_page) != head);
 	SetPageError(page);
 	BUG_ON(PageWriteback(page));
-	mapping_set_error(page->mapping, err);
+	mapping_set_error(mapping, err);
 	set_page_writeback(page);
 	do {
 		struct buffer_head *next = bh->b_this_page;

@@ -1767,8 +1770,8 @@ static int __block_prepare_write(struct 
 	struct buffer_head *bh, *head, *wait[2], **wait_bh=wait;
 
 	BUG_ON(!PageLocked(page));
-	BUG_ON(from > PAGE_CACHE_SIZE);
-	BUG_ON(to > PAGE_CACHE_SIZE);
+	BUG_ON(from > page_cache_size(inode->i_mapping));
+	BUG_ON(to > page_cache_size(inode->i_mapping));
 	BUG_ON(from > to);
 
 	blocksize = 1 << inode->i_blkbits;

@@ -1777,7 +1780,8 @@ static int __block_prepare_write(struct 
 	head = page_buffers(page);
 
 	bbits = inode->i_blkbits;
-	block = (sector_t)page->index << (PAGE_CACHE_SHIFT - bbits);
+	block = (sector_t)page->index <<
+		(page_cache_shift(inode->i_mapping) - bbits);
 
 	for(bh = head, block_start = 0; bh != head || !block_start;
 	    block++, block_start=block_end, bh = bh->b_this_page) {

@@ -1921,7 +1925,8 @@ int block_read_full_page(struct page *pa
 		create_empty_buffers(page, blocksize, 0);
 	head = page_buffers(page);
 
-	iblock = (sector_t)page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
+	iblock = (sector_t)page->index <<
+		(page_cache_shift(page->mapping) - inode->i_blkbits);
 	lblock = (i_size_read(inode)+blocksize-1) >> inode->i_blkbits;
 	bh = head;
 	nr = 0;

@@ -2045,7 +2050,7 @@ int generic_cont_expand(struct inode *in
 	pgoff_t index;
 	unsigned int offset;
 
-	offset = (size & (PAGE_CACHE_SIZE - 1)); /* Within page */
+	offset = page_cache_offset(inode->i_mapping, size); /* Within page */
 
 	/* ugh.  in prepare/commit_write, if from==to==start of block, we
 	** skip the prepare.  make sure we never send an offset for the start

@@ -2055,7 +2060,7 @@ int generic_cont_expand(struct inode *in
 		/* caller must handle this extra byte. */
 		offset++;
 	}
-	index = size >> PAGE_CACHE_SHIFT;
+	index = page_cache_index(inode->i_mapping, size);
 
 	return __generic_cont_expand(inode, size, index, offset);
 }

@@ -2063,8 +2068,8 @@ int generic_cont_expand(struct inode *in
 int generic_cont_expand_simple(struct inode *inode, loff_t size)
 {
 	loff_t pos = size - 1;
-	pgoff_t index = pos >> PAGE_CACHE_SHIFT;
-	unsigned int offset = (pos & (PAGE_CACHE_SIZE - 1)) + 1;
+	pgoff_t index = page_cache_index(inode->i_mapping, pos);
+	unsigned int offset = page_cache_offset(inode->i_mapping, pos) + 1;
 
 	/* prepare/commit_write can handle even if from==to==start of block. */
 	return __generic_cont_expand(inode, size, index, offset);

@@ -2086,28 +2091,28 @@ int cont_prepare_write(struct page *page
 	unsigned zerofrom;
 	unsigned blocksize = 1 << inode->i_blkbits;
 
-	while(page->index > (pgpos = *bytes>>PAGE_CACHE_SHIFT)) {
+	while (page->index > (pgpos = page_cache_index(mapping, *bytes))) {
 		status = -ENOMEM;
 		new_page = grab_cache_page(mapping, pgpos);
 		if (!new_page)
 			goto out;
 		/* we might sleep */
-		if (*bytes>>PAGE_CACHE_SHIFT != pgpos) {
+		if (page_cache_index(mapping, *bytes) != pgpos) {
 			unlock_page(new_page);
 			page_cache_release(new_page);
 			continue;
 		}
-		zerofrom = *bytes & ~PAGE_CACHE_MASK;
+		zerofrom = page_cache_offset(mapping, *bytes);
 		if (zerofrom & (blocksize-1)) {
 			*bytes |= (blocksize-1);
 			(*bytes)++;
 		}
 		status = __block_prepare_write(inode, new_page, zerofrom,
-						PAGE_CACHE_SIZE, get_block);
+					page_cache_size(mapping), get_block);
 		if (status)
 			goto out_unmap;
-		zero_user_segment(new_page, zerofrom, PAGE_CACHE_SIZE);
-		generic_commit_write(NULL, new_page, zerofrom, PAGE_CACHE_SIZE);
+		zero_user_segment(new_page, zerofrom, page_cache_size(mapping));
+		generic_commit_write(NULL, new_page, zerofrom, page_cache_size(mapping));
 		unlock_page(new_page);
 		page_cache_release(new_page);
 	}

@@ -2117,7 +2122,7 @@ int cont_prepare_write(struct page *page
 		zerofrom = offset;
 	} else {
 		/* page covers the boundary, find the boundary offset */
-		zerofrom = *bytes & ~PAGE_CACHE_MASK;
+		zerofrom = page_cache_offset(mapping, *bytes);
 
 		/* if we will expand the thing last block will be filled */
 		if (to > zerofrom && (zerofrom & (blocksize-1))) {

@@ -2169,8 +2174,9 @@ int block_commit_write(struct page *page
 int generic_commit_write(struct file *file, struct page *page,
 		unsigned from, unsigned to)
 {
-	struct inode *inode = page->mapping->host;
-	loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
+	struct address_space *mapping = page->mapping;
+	struct inode *inode = mapping->host;
+	loff_t pos = page_cache_pos(mapping, page->index, to);
 	__block_commit_write(inode,page,from,to);
 	/*
 	 * No need to use i_size_read() here, the i_size

@@ -2206,20 +2212,22 @@ block_page_mkwrite(struct vm_area_struct
 	unsigned long end;
 	loff_t size;
 	int ret = -EINVAL;
+	struct address_space *mapping;
 
 	lock_page(page);
+	mapping = page->mapping;
 	size = i_size_read(inode);
-	if ((page->mapping != inode->i_mapping) ||
+	if ((mapping != inode->i_mapping) ||
 	    (page_offset(page) > size)) {
 		/* page got truncated out from underneath us */
 		goto out_unlock;
 	}
 
 	/* page is wholly or partially inside EOF */
-	if (((page->index + 1) << PAGE_CACHE_SHIFT) > size)
-		end = size & ~PAGE_CACHE_MASK;
+	if (page_cache_pos(mapping, page->index + 1, 0) > size)
+		end = page_cache_offset(mapping, size);
 	else
-		end = PAGE_CACHE_SIZE;
+		end = page_cache_size(mapping);
 
 	ret = block_prepare_write(page, 0, end, get_block);
 	if (!ret)

@@ -2258,6 +2266,7 @@ static void end_buffer_read_nobh(struct 
 int nobh_prepare_write(struct page *page, unsigned from, unsigned to,
 			get_block_t *get_block)
 {
+	struct address_space *mapping = page->mapping;
 	struct inode *inode = page->mapping->host;
 	const unsigned blkbits = inode->i_blkbits;
 	const unsigned blocksize = 1 << blkbits;

@@ -2265,6 +2274,7 @@ int nobh_prepare_write(struct page *page
 	struct buffer_head *read_bh[MAX_BUF_PER_PAGE];
 	unsigned block_in_page;
 	unsigned block_start;
+	unsigned page_size = page_cache_size(mapping);
 	sector_t block_in_file;
 	int nr_reads = 0;
 	int i;

@@ -2274,7 +2284,8 @@ int nobh_prepare_write(struct page *page
 	if (PageMappedToDisk(page))
 		return 0;
 
-	block_in_file = (sector_t)page->index << (PAGE_CACHE_SHIFT - blkbits);
+	block_in_file = (sector_t)page->index <<
+			(page_cache_shift(mapping) - blkbits);
 	map_bh.b_page = page;
 
 	/*

@@ -2283,7 +2294,7 @@ int nobh_prepare_write(struct page *page
 	 * page is fully mapped-to-disk.
 	 */
 	for (block_start = 0, block_in_page = 0;
-		  block_start < PAGE_CACHE_SIZE;
+		  block_start < page_size;
 		  block_in_page++, block_start += blocksize) {
 		unsigned block_end = block_start + blocksize;
 		int create;

@@ -2372,7 +2383,7 @@ failed:
 	 * Error recovery is pretty slack.  Clear the page and mark it dirty
 	 * so we'll later zero out any blocks which _were_ allocated.
 	 */
-	zero_user(page, 0, PAGE_CACHE_SIZE);
+	zero_user(page, 0, page_size);
 	SetPageUptodate(page);
 	set_page_dirty(page);
 	return ret;

@@ -2386,8 +2397,9 @@ EXPORT_SYMBOL(nobh_prepare_write);
 int nobh_commit_write(struct file *file, struct page *page,
 		unsigned from, unsigned to)
 {
-	struct inode *inode = page->mapping->host;
-	loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
+	struct address_space *mapping = page->mapping;
+	struct inode *inode = mapping->host;
+	loff_t pos = page_cache_pos(mapping, page->index, to);
 
 	SetPageUptodate(page);
 	set_page_dirty(page);

@@ -2407,9 +2419,10 @@ EXPORT_SYMBOL(nobh_commit_write);
 int nobh_writepage(struct page *page, get_block_t *get_block,
 			struct writeback_control *wbc)
 {
-	struct inode * const inode = page->mapping->host;
+	struct address_space *mapping = page->mapping;
+	struct inode * const inode = mapping->host;
 	loff_t i_size = i_size_read(inode);
-	const pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
+	const pgoff_t end_index = page_cache_offset(mapping, i_size);
 	unsigned offset;
 	int ret;
 

@@ -2418,7 +2431,7 @@ int nobh_writepage(struct page *page, ge
 		goto out;
 
 	/* Is the page fully outside i_size? (truncate in progress) */
-	offset = i_size & (PAGE_CACHE_SIZE-1);
+	offset = page_cache_offset(mapping, i_size);
 	if (page->index >= end_index+1 || !offset) {
 		/*
 		 * The page may have dirty, unmapped buffers.  For example,

@@ -2441,7 +2454,7 @@ int nobh_writepage(struct page *page, ge
 	 * the  page size, the remaining memory is zeroed when mapped, and
 	 * writes to that region are not written out to the file."
 	 */
-	zero_user_segment(page, offset, PAGE_CACHE_SIZE);
+	zero_user_segment(page, offset, page_cache_size(mapping));
 out:
 	ret = mpage_writepage(page, get_block, wbc);
 	if (ret == -EAGAIN)

@@ -2457,8 +2470,8 @@ int nobh_truncate_page(struct address_sp
 {
 	struct inode *inode = mapping->host;
 	unsigned blocksize = 1 << inode->i_blkbits;
-	pgoff_t index = from >> PAGE_CACHE_SHIFT;
-	unsigned offset = from & (PAGE_CACHE_SIZE-1);
+	pgoff_t index = page_cache_index(mapping, from);
+	unsigned offset = page_cache_offset(mapping, from);
 	unsigned to;
 	struct page *page;
 	const struct address_space_operations *a_ops = mapping->a_ops;

@@ -2475,7 +2488,7 @@ int nobh_truncate_page(struct address_sp
 	to = (offset + blocksize) & ~(blocksize - 1);
 	ret = a_ops->prepare_write(NULL, page, offset, to);
 	if (ret == 0) {
-		zero_user_segment(page, offset, PAGE_CACHE_SIZE);
+		zero_user_segment(page, offset, page_cache_size(mapping));
 		/*
 		 * It would be more correct to call aops->commit_write()
 		 * here, but this is more efficient.

@@ -2493,8 +2506,8 @@ EXPORT_SYMBOL(nobh_truncate_page);
 int block_truncate_page(struct address_space *mapping,
 			loff_t from, get_block_t *get_block)
 {
-	pgoff_t index = from >> PAGE_CACHE_SHIFT;
-	unsigned offset = from & (PAGE_CACHE_SIZE-1);
+	pgoff_t index = page_cache_index(mapping, from);
+	unsigned offset = page_cache_offset(mapping, from);
 	unsigned blocksize;
 	sector_t iblock;
 	unsigned length, pos;

@@ -2511,8 +2524,8 @@ int block_truncate_page(struct address_s
 		return 0;
 
 	length = blocksize - length;
-	iblock = (sector_t)index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
-	
+	iblock = (sector_t)index <<
+			(page_cache_shift(mapping) - inode->i_blkbits);
 	page = grab_cache_page(mapping, index);
 	err = -ENOMEM;
 	if (!page)

@@ -2571,9 +2584,10 @@ out:
 int block_write_full_page(struct page *page, get_block_t *get_block,
 			struct writeback_control *wbc)
 {
-	struct inode * const inode = page->mapping->host;
+	struct address_space *mapping = page->mapping;
+	struct inode * const inode = mapping->host;
 	loff_t i_size = i_size_read(inode);
-	const pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
+	const pgoff_t end_index = page_cache_index(mapping, i_size);
 	unsigned offset;
 
 	/* Is the page fully inside i_size? */

@@ -2581,7 +2595,7 @@ int block_write_full_page(struct page *p
 		return __block_write_full_page(inode, page, get_block, wbc);
 
 	/* Is the page fully outside i_size? (truncate in progress) */
-	offset = i_size & (PAGE_CACHE_SIZE-1);
+	offset = page_cache_offset(mapping, i_size);
 	if (page->index >= end_index+1 || !offset) {
 		/*
 		 * The page may have dirty, unmapped buffers.  For example,

@@ -2600,7 +2614,7 @@ int block_write_full_page(struct page *p
 	 * the  page size, the remaining memory is zeroed when mapped, and
 	 * writes to that region are not written out to the file."
 	 */
-	zero_user_segment(page, offset, PAGE_CACHE_SIZE);
+	zero_user_segment(page, offset, page_cache_size(mapping));
 	return __block_write_full_page(inode, page, get_block, wbc);
 }
 

@@ -2854,7 +2868,7 @@ int try_to_free_buffers(struct page *pag
 	 * dirty bit from being lost.
 	 */
 	if (ret)
-		cancel_dirty_page(page, PAGE_CACHE_SIZE);
+		cancel_dirty_page(page, page_cache_size(mapping));
 	spin_unlock(&mapping->private_lock);
 out:
 	if (buffers_to_free) {

index a5e1385..2843ed7 100644
@@ -133,7 +133,8 @@ mpage_alloc(struct block_device *bdev,
 static void 
 map_buffer_to_page(struct page *page, struct buffer_head *bh, int page_block) 
 {
-	struct inode *inode = page->mapping->host;
+	struct address_space *mapping = page->mapping;
+	struct inode *inode = mapping->host;
 	struct buffer_head *page_bh, *head;
 	int block = 0;
 

@@ -142,9 +143,9 @@ map_buffer_to_page(struct page *page, struct buffer_head *bh, int page_block)
 		 * don't make any buffers if there is only one buffer on
 		 * the page and the page just needs to be set up to date
 		 */
-		if (inode->i_blkbits == PAGE_CACHE_SHIFT && 
+		if (inode->i_blkbits == page_cache_shift(mapping) &&
 		    buffer_uptodate(bh)) {
-			SetPageUptodate(page);    
+			SetPageUptodate(page);
 			return;
 		}
 		create_empty_buffers(page, 1 << inode->i_blkbits, 0);

@@ -177,9 +178,10 @@ do_mpage_readpage(struct bio *bio, struct page *page, unsigned nr_pages,
 		sector_t *last_block_in_bio, struct buffer_head *map_bh,
 		unsigned long *first_logical_block, get_block_t get_block)
 {
-	struct inode *inode = page->mapping->host;
+	struct address_space *mapping = page->mapping;
+	struct inode *inode = mapping->host;
 	const unsigned blkbits = inode->i_blkbits;
-	const unsigned blocks_per_page = PAGE_CACHE_SIZE >> blkbits;
+	const unsigned blocks_per_page = page_cache_size(mapping) >> blkbits;
 	const unsigned blocksize = 1 << blkbits;
 	sector_t block_in_file;
 	sector_t last_block;

@@ -196,7 +198,7 @@ do_mpage_readpage(struct bio *bio, struct page *page, unsigned nr_pages,
 	if (page_has_buffers(page))
 		goto confused;
 
-	block_in_file = (sector_t)page->index << (PAGE_CACHE_SHIFT - blkbits);
+	block_in_file = (sector_t)page->index << (page_cache_shift(mapping) - blkbits);
 	last_block = block_in_file + nr_pages * blocks_per_page;
 	last_block_in_file = (i_size_read(inode) + blocksize - 1) >> blkbits;
 	if (last_block > last_block_in_file)

@@ -284,7 +286,8 @@ do_mpage_readpage(struct bio *bio, struct page *page, unsigned nr_pages,
 	}
 
 	if (first_hole != blocks_per_page) {
-		zero_user_segment(page, first_hole << blkbits, PAGE_CACHE_SIZE);
+		zero_user_segment(page, first_hole << blkbits,
+					page_cache_size(mapping));
 		if (first_hole == 0) {
 			SetPageUptodate(page);
 			unlock_page(page);

@@ -468,7 +471,7 @@ static int __mpage_writepage(struct page *page, struct writeback_control *wbc,
 	struct inode *inode = page->mapping->host;
 	const unsigned blkbits = inode->i_blkbits;
 	unsigned long end_index;
-	const unsigned blocks_per_page = PAGE_CACHE_SIZE >> blkbits;
+	const unsigned blocks_per_page = page_cache_size(mapping) >> blkbits;
 	sector_t last_block;
 	sector_t block_in_file;
 	sector_t blocks[MAX_BUF_PER_PAGE];

@@ -537,7 +540,8 @@ static int __mpage_writepage(struct page *page, struct writeback_control *wbc,
 	 * The page has no buffers: map it to disk
 	 */
 	BUG_ON(!PageUptodate(page));
-	block_in_file = (sector_t)page->index << (PAGE_CACHE_SHIFT - blkbits);
+	block_in_file = (sector_t)page->index <<
+			(page_cache_shift(mapping) - blkbits);
 	last_block = (i_size - 1) >> blkbits;
 	map_bh.b_page = page;
 	for (page_block = 0; page_block < blocks_per_page; ) {

@@ -569,7 +573,7 @@ static int __mpage_writepage(struct page *page, struct writeback_control *wbc,
 	first_unmapped = page_block;
 
 page_is_mapped:
-	end_index = i_size >> PAGE_CACHE_SHIFT;
+	end_index = page_cache_index(mapping, i_size);
 	if (page->index >= end_index) {
 		/*
 		 * The page straddles i_size.  It must be zeroed out on each

@@ -579,11 +583,11 @@ page_is_mapped:
 		 * is zeroed when mapped, and writes to that region are not
 		 * written out to the file."
 		 */
-		unsigned offset = i_size & (PAGE_CACHE_SIZE - 1);
+		unsigned offset = page_cache_offset(mapping, i_size);
 
 		if (page->index > end_index || !offset)
 			goto confused;
-		zero_user_segment(page, offset, PAGE_CACHE_SIZE);
+		zero_user_segment(page, offset, page_cache_size(mapping));
 	}
 
 	/*

index 0df4c89..804c2a9 100644
@@ -79,8 +79,8 @@ asmlinkage long sys_fadvise64_64(int fd, loff_t offset, loff_t len, int advice)
 		}
 
 		/* First and last PARTIAL page! */
-		start_index = offset >> PAGE_CACHE_SHIFT;
-		end_index = endbyte >> PAGE_CACHE_SHIFT;
+		start_index = page_cache_index(mapping, offset);
+		end_index = page_cache_index(mapping, endbyte);
 
 		/* Careful about overflow on the "+1" */
 		nrpages = end_index - start_index + 1;

@@ -100,8 +100,8 @@ asmlinkage long sys_fadvise64_64(int fd, loff_t offset, loff_t len, int advice)
 			filemap_flush(mapping);
 
 		/* First and last FULL page! */
-		start_index = (offset+(PAGE_CACHE_SIZE-1)) >> PAGE_CACHE_SHIFT;
-		end_index = (endbyte >> PAGE_CACHE_SHIFT);
+		start_index = page_cache_next(mapping, offset);
+		end_index = page_cache_index(mapping, endbyte);
 
 		if (end_index >= start_index)
 			invalidate_mapping_pages(mapping, start_index,

index c010a72..7910f32 100644
@@ -279,9 +279,9 @@ __generic_file_splice_read(struct file *in, loff_t *ppos,
 		.ops = &page_cache_pipe_buf_ops,
 	};
 
-	index = *ppos >> PAGE_CACHE_SHIFT;
-	loff = *ppos & ~PAGE_CACHE_MASK;
-	req_pages = (len + loff + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+	index = page_cache_index(mapping, *ppos);
+	loff = page_cache_offset(mapping, *ppos);
+	req_pages = page_cache_next(mapping, len + loff);
 	nr_pages = min(req_pages, (unsigned)PIPE_BUFFERS);
 
 	/*

@@ -336,7 +336,7 @@ __generic_file_splice_read(struct file *in, loff_t *ppos,
 	 * Now loop over the map and see if we need to start IO on any
 	 * pages, fill in the partial map, etc.
 	 */
-	index = *ppos >> PAGE_CACHE_SHIFT;
+	index = page_cache_index(mapping, *ppos);
 	nr_pages = spd.nr_pages;
 	spd.nr_pages = 0;
 	for (page_nr = 0; page_nr < nr_pages; page_nr++) {

@@ -348,7 +348,8 @@ __generic_file_splice_read(struct file *in, loff_t *ppos,
 		/*
 		 * this_len is the max we'll use from this page
 		 */
-		this_len = min_t(unsigned long, len, PAGE_CACHE_SIZE - loff);
+		this_len = min_t(unsigned long, len,
+					page_cache_size(mapping) - loff);
 		page = pages[page_nr];
 
 		if (PageReadahead(page))

@@ -408,7 +409,7 @@ fill_it:
 		 * i_size must be checked after PageUptodate.
 		 */
 		isize = i_size_read(mapping->host);
-		end_index = (isize - 1) >> PAGE_CACHE_SHIFT;
+		end_index = page_cache_index(mapping, isize - 1);
 		if (unlikely(!isize || index > end_index))
 			break;
 

@@ -422,7 +423,7 @@ fill_it:
 			/*
 			 * max good bytes in this page
 			 */
-			plen = ((isize - 1) & ~PAGE_CACHE_MASK) + 1;
+			plen = page_cache_offset(mapping, isize - 1) + 1;
 			if (plen <= loff)
 				break;
 

@@ -573,12 +574,12 @@ static int pipe_to_file(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
 	if (unlikely(ret))
 		return ret;
 
-	index = sd->pos >> PAGE_CACHE_SHIFT;
-	offset = sd->pos & ~PAGE_CACHE_MASK;
+	index = page_cache_index(mapping, sd->pos);
+	offset = page_cache_offset(mapping, sd->pos);
 
 	this_len = sd->len;
-	if (this_len + offset > PAGE_CACHE_SIZE)
-		this_len = PAGE_CACHE_SIZE - offset;
+	if (this_len + offset > page_cache_size(mapping))
+		this_len = page_cache_size(mapping) - offset;
 
 find_page:
 	page = find_lock_page(mapping, index);

@@ -839,7 +840,7 @@ generic_file_splice_write_nolock(struct pipe_inode_info *pipe, struct file *out,
 		unsigned long nr_pages;
 
 		*ppos += ret;
-		nr_pages = (ret + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+		nr_pages = page_cache_next(mapping, ret);
 
 		/*
 		 * If file or inode is SYNC and we actually wrote some data,

@@ -896,7 +897,7 @@ generic_file_splice_write(struct pipe_inode_info *pipe, struct file *out,
 		unsigned long nr_pages;
 
 		*ppos += ret;
-		nr_pages = (ret + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+		nr_pages = page_cache_next(mapping, ret);
 
 		/*
 		 * If file or inode is SYNC and we actually wrote some data,

index 2bf49d7..d72926f 100644
@@ -43,7 +43,8 @@ static inline void ext2_put_page(struct page *page)
 
 static inline unsigned long dir_pages(struct inode *inode)
 {
-	return (inode->i_size+PAGE_CACHE_SIZE-1)>>PAGE_CACHE_SHIFT;
+	return (inode->i_size+page_cache_size(inode->i_mapping)-1)>>
+			page_cache_shift(inode->i_mapping);
 }
 
 /*

@@ -54,10 +55,11 @@ static unsigned
 ext2_last_byte(struct inode *inode, unsigned long page_nr)
 {
 	unsigned last_byte = inode->i_size;
+	struct address_space *mapping = inode->i_mapping;
 
-	last_byte -= page_nr << PAGE_CACHE_SHIFT;
-	if (last_byte > PAGE_CACHE_SIZE)
-		last_byte = PAGE_CACHE_SIZE;
+	last_byte -= page_nr << page_cache_shift(mapping);
+	if (last_byte > page_cache_size(mapping))
+		last_byte = page_cache_size(mapping);
 	return last_byte;
 }
 

@@ -76,18 +78,19 @@ static int ext2_commit_chunk(struct page *page, unsigned from, unsigned to)
 
 static void ext2_check_page(struct page *page)
 {
-	struct inode *dir = page->mapping->host;
+	struct address_space *mapping = page->mapping;
+	struct inode *dir = mapping->host;
 	struct super_block *sb = dir->i_sb;
 	unsigned chunk_size = ext2_chunk_size(dir);
 	char *kaddr = page_address(page);
 	u32 max_inumber = le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count);
 	unsigned offs, rec_len;
-	unsigned limit = PAGE_CACHE_SIZE;
+	unsigned limit = page_cache_size(mapping);
 	ext2_dirent *p;
 	char *error;
 
-	if ((dir->i_size >> PAGE_CACHE_SHIFT) == page->index) {
-		limit = dir->i_size & ~PAGE_CACHE_MASK;
+	if (page_cache_index(mapping, dir->i_size) == page->index) {
+		limit = page_cache_offset(mapping, dir->i_size);
 		if (limit & (chunk_size - 1))
 			goto Ebadsize;
 		if (!limit)

@@ -139,7 +142,7 @@ Einumber:
 bad_entry:
 	ext2_error (sb, "ext2_check_page", "bad entry in directory #%lu: %s - "
 		"offset=%lu, inode=%lu, rec_len=%d, name_len=%d",
-		dir->i_ino, error, (page->index<<PAGE_CACHE_SHIFT)+offs,
+		dir->i_ino, error, page_cache_pos(mapping, page->index, offs),
 		(unsigned long) le32_to_cpu(p->inode),
 		rec_len, p->name_len);
 	goto fail;

@@ -148,7 +151,7 @@ Eend:
 	ext2_error (sb, "ext2_check_page",
 		"entry in directory #%lu spans the page boundary"
 		"offset=%lu, inode=%lu",
-		dir->i_ino, (page->index<<PAGE_CACHE_SHIFT)+offs,
+		dir->i_ino, page_cache_pos(mapping, page->index, offs),
 		(unsigned long) le32_to_cpu(p->inode));
 fail:
 	SetPageChecked(page);

@@ -246,8 +249,9 @@ ext2_readdir (struct file * filp, void * dirent, filldir_t filldir)
 	loff_t pos = filp->f_pos;
 	struct inode *inode = filp->f_path.dentry->d_inode;
 	struct super_block *sb = inode->i_sb;
-	unsigned int offset = pos & ~PAGE_CACHE_MASK;
-	unsigned long n = pos >> PAGE_CACHE_SHIFT;
+	struct address_space *mapping = inode->i_mapping;
+	unsigned int offset = page_cache_offset(mapping, pos);
+	unsigned long n = page_cache_index(mapping, pos);
 	unsigned long npages = dir_pages(inode);
 	unsigned chunk_mask = ~(ext2_chunk_size(inode)-1);
 	unsigned char *types = NULL;

@@ -268,14 +272,14 @@ ext2_readdir (struct file * filp, void * dirent, filldir_t filldir)
 			ext2_error(sb, __FUNCTION__,
 				   "bad page in #%lu",
 				   inode->i_ino);
-			filp->f_pos += PAGE_CACHE_SIZE - offset;
+			filp->f_pos += page_cache_size(mapping) - offset;
 			return -EIO;
 		}
 		kaddr = page_address(page);
 		if (unlikely(need_revalidate)) {
 			if (offset) {
 				offset = ext2_validate_entry(kaddr, offset, chunk_mask);
-				filp->f_pos = (n<<PAGE_CACHE_SHIFT) + offset;
+				filp->f_pos = page_cache_pos(mapping, n, offset);
 			}
 			filp->f_version = inode->i_version;
 			need_revalidate = 0;

@@ -298,7 +302,7 @@ ext2_readdir (struct file * filp, void * dirent, filldir_t filldir)
 
 				offset = (char *)de - kaddr;
 				over = filldir(dirent, de->name, de->name_len,
-						(n<<PAGE_CACHE_SHIFT) | offset,
+						page_cache_pos(mapping, n, offset),
 						le32_to_cpu(de->inode), d_type);
 				if (over) {
 					ext2_put_page(page);

@@ -324,6 +328,7 @@ struct ext2_dir_entry_2 * ext2_find_entry (struct inode * dir,
 			struct dentry *dentry, struct page ** res_page)
 {
 	const char *name = dentry->d_name.name;
+	struct address_space *mapping = dir->i_mapping;
 	int namelen = dentry->d_name.len;
 	unsigned reclen = EXT2_DIR_REC_LEN(namelen);
 	unsigned long start, n;

@@ -365,7 +370,7 @@ struct ext2_dir_entry_2 * ext2_find_entry (struct inode * dir,
 		if (++n >= npages)
 			n = 0;
 		/* next page is past the blocks we've got */
-		if (unlikely(n > (dir->i_blocks >> (PAGE_CACHE_SHIFT - 9)))) {
+		if (unlikely(n > (dir->i_blocks >> (page_cache_shift(mapping) - 9)))) {
 			ext2_error(dir->i_sb, __FUNCTION__,
 				"dir %lu size %lld exceeds block count %llu",
 				dir->i_ino, dir->i_size,

@@ -434,6 +439,7 @@ void ext2_set_link(struct inode *dir, struct ext2_dir_entry_2 *de,
 int ext2_add_link (struct dentry *dentry, struct inode *inode)
 {
 	struct inode *dir = dentry->d_parent->d_inode;
+	struct address_space *mapping = inode->i_mapping;
 	const char *name = dentry->d_name.name;
 	int namelen = dentry->d_name.len;
 	unsigned chunk_size = ext2_chunk_size(dir);

@@ -463,7 +469,7 @@ int ext2_add_link (struct dentry *dentry, struct inode *inode)
 		kaddr = page_address(page);
 		dir_end = kaddr + ext2_last_byte(dir, n);
 		de = (ext2_dirent *)kaddr;
-		kaddr += PAGE_CACHE_SIZE - reclen;
+		kaddr += page_cache_size(mapping) - reclen;
 		while ((char *)de <= kaddr) {
 			if ((char *)de == dir_end) {
 				/* We hit i_size */

index c00723a..a65b5a7 100644
@@ -137,7 +137,8 @@ static int ext3_readdir(struct file * filp,
 						&map_bh, 0, 0);
 		if (err > 0) {
 			pgoff_t index = map_bh.b_blocknr >>
-					(PAGE_CACHE_SHIFT - inode->i_blkbits);
+				(page_cache_shift(inode->i_mapping)
+					- inode->i_blkbits);
 			if (!ra_has_index(&filp->f_ra, index))
 				page_cache_sync_readahead(
 					sb->s_bdev->bd_inode->i_mapping,

index eb3c264..986519b 100644
@@ -1224,7 +1224,7 @@ static int ext3_ordered_commit_write(struct file *file, struct page *page,
 		 */
 		loff_t new_i_size;
 
-		new_i_size = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
+		new_i_size = page_cache_pos(page->mapping, page->index, to);
 		if (new_i_size > EXT3_I(inode)->i_disksize)
 			EXT3_I(inode)->i_disksize = new_i_size;
 		ret = generic_commit_write(file, page, from, to);

@@ -1243,7 +1243,7 @@ static int ext3_writeback_commit_write(struct file *file, struct page *page,
 	int ret = 0, ret2;
 	loff_t new_i_size;
 
-	new_i_size = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
+	new_i_size = page_cache_pos(inode->i_mapping, page->index, to);
 	if (new_i_size > EXT3_I(inode)->i_disksize)
 		EXT3_I(inode)->i_disksize = new_i_size;
 

@@ -1270,7 +1270,7 @@ static int ext3_journalled_commit_write(struct file *file,
 	/*
 	 * Here we duplicate the generic_commit_write() functionality
 	 */
-	pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
+	pos = page_cache_pos(page->mapping, page->index, to);
 
 	ret = walk_page_buffers(handle, page_buffers(page), from,
 				to, &partial, commit_write_fn);

@@ -1422,6 +1422,7 @@ static int ext3_ordered_writepage(struct page *page,
 	handle_t *handle = NULL;
 	int ret = 0;
 	int err;
+	int pagesize = page_cache_size(inode->i_mapping);
 
 	J_ASSERT(PageLocked(page));
 

@@ -1444,8 +1445,7 @@ static int ext3_ordered_writepage(struct page *page,
 				(1 << BH_Dirty)|(1 << BH_Uptodate));
 	}
 	page_bufs = page_buffers(page);
-	walk_page_buffers(handle, page_bufs, 0,
-			PAGE_CACHE_SIZE, NULL, bget_one);
+	walk_page_buffers(handle, page_bufs, 0, pagesize, NULL, bget_one);
 
 	ret = block_write_full_page(page, ext3_get_block, wbc);
 

@@ -1462,13 +1462,12 @@ static int ext3_ordered_writepage(struct page *page,
 	 * and generally junk.
 	 */
 	if (ret == 0) {
-		err = walk_page_buffers(handle, page_bufs, 0, PAGE_CACHE_SIZE,
-					NULL, journal_dirty_data_fn);
+		err = walk_page_buffers(handle, page_bufs, 0, pagesize,
+			NULL, journal_dirty_data_fn);
 		if (!ret)
 			ret = err;
 	}
-	walk_page_buffers(handle, page_bufs, 0,
-			PAGE_CACHE_SIZE, NULL, bput_one);
+	walk_page_buffers(handle, page_bufs, 0, pagesize, NULL, bput_one);
 	err = ext3_journal_stop(handle);
 	if (!ret)
 		ret = err;

@@ -1520,6 +1519,7 @@ static int ext3_journalled_writepage(struct page *page,
 	handle_t *handle = NULL;
 	int ret = 0;
 	int err;
+	int pagesize = page_cache_size(inode->i_mapping);
 
 	if (ext3_journal_current_handle())
 		goto no_write;

@@ -1536,17 +1536,16 @@ static int ext3_journalled_writepage(struct page *page,
 		 * doesn't seem much point in redirtying the page here.
 		 */
 		ClearPageChecked(page);
-		ret = block_prepare_write(page, 0, PAGE_CACHE_SIZE,
-					ext3_get_block);
+		ret = block_prepare_write(page, 0, pagesize, ext3_get_block);
 		if (ret != 0) {
 			ext3_journal_stop(handle);
 			goto out_unlock;
 		}
 		ret = walk_page_buffers(handle, page_buffers(page), 0,
-			PAGE_CACHE_SIZE, NULL, do_journal_get_write_access);
+			pagesize, NULL, do_journal_get_write_access);
 
 		err = walk_page_buffers(handle, page_buffers(page), 0,
-				PAGE_CACHE_SIZE, NULL, commit_write_fn);
+				pagesize, NULL, commit_write_fn);
 		if (ret == 0)
 			ret = err;
 		EXT3_I(inode)->i_state |= EXT3_STATE_JDATA;

@@ -1761,8 +1760,8 @@ void ext3_set_aops(struct inode *inode)
 static int ext3_block_truncate_page(handle_t *handle, struct page *page,
 		struct address_space *mapping, loff_t from)
 {
-	ext3_fsblk_t index = from >> PAGE_CACHE_SHIFT;
-	unsigned offset = from & (PAGE_CACHE_SIZE-1);
+	ext3_fsblk_t index = page_cache_index(mapping, from);
+	unsigned offset = page_cache_offset(mapping, from);
 	unsigned blocksize, iblock, length, pos;
 	struct inode *inode = mapping->host;
 	struct buffer_head *bh;

@@ -1770,7 +1769,8 @@ static int ext3_block_truncate_page(handle_t *handle, struct page *page,
 
 	blocksize = inode->i_sb->s_blocksize;
 	length = blocksize - (offset & (blocksize - 1));
-	iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
+	iblock = index <<
+		(page_cache_shift(mapping) - inode->i_sb->s_blocksize_bits);
 
 	/*
 	 * For "nobh" option,  we can only work if we don't need to

@@ -2249,7 +2249,7 @@ void ext3_truncate(struct inode *inode)
 		page = NULL;
 	} else {
 		page = grab_cache_page(mapping,
-				inode->i_size >> PAGE_CACHE_SHIFT);
+				page_cache_index(mapping, inode->i_size));
 		if (!page)
 			return;
 	}

index 3ab01c0..9d6cd51 100644
@@ -136,7 +136,8 @@ static int ext4_readdir(struct file * filp,
 		err = ext4_get_blocks_wrap(NULL, inode, blk, 1, &map_bh, 0, 0);
 		if (err > 0) {
 			pgoff_t index = map_bh.b_blocknr >>
-					(PAGE_CACHE_SHIFT - inode->i_blkbits);
+				(page_cache_size(node->i_mapping)
+					- inode->i_blkbits);
 			if (!ra_has_index(&filp->f_ra, index))
 				page_cache_sync_readahead(
 					sb->s_bdev->bd_inode->i_mapping,

index 3fe1e40..0be5bf8 100644
@@ -1223,7 +1223,7 @@ static int ext4_ordered_commit_write(struct file *file, struct page *page,
 		 */
 		loff_t new_i_size;
 
-		new_i_size = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
+		new_i_size = page_cache_pos(page->mapping, page->index, to);
 		if (new_i_size > EXT4_I(inode)->i_disksize)
 			EXT4_I(inode)->i_disksize = new_i_size;
 		ret = generic_commit_write(file, page, from, to);

@@ -1242,7 +1242,7 @@ static int ext4_writeback_commit_write(struct file *file, struct page *page,
 	int ret = 0, ret2;
 	loff_t new_i_size;
 
-	new_i_size = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
+	new_i_size = page_cache_pos(page->mapping, page->index, to);
 	if (new_i_size > EXT4_I(inode)->i_disksize)
 		EXT4_I(inode)->i_disksize = new_i_size;
 

@@ -1269,7 +1269,7 @@ static int ext4_journalled_commit_write(struct file *file,
 	/*
 	 * Here we duplicate the generic_commit_write() functionality
 	 */
-	pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
+	pos = page_cache_pos(page->mapping, page->index, to);
 
 	ret = walk_page_buffers(handle, page_buffers(page), from,
 				to, &partial, commit_write_fn);

@@ -1421,6 +1421,7 @@ static int ext4_ordered_writepage(struct page *page,
 	handle_t *handle = NULL;
 	int ret = 0;
 	int err;
+	int pagesize = page_cache_size(inode->i_mapping);
 
 	J_ASSERT(PageLocked(page));
 

@@ -1443,8 +1444,7 @@ static int ext4_ordered_writepage(struct page *page,
 				(1 << BH_Dirty)|(1 << BH_Uptodate));
 	}
 	page_bufs = page_buffers(page);
-	walk_page_buffers(handle, page_bufs, 0,
-			PAGE_CACHE_SIZE, NULL, bget_one);
+	walk_page_buffers(handle, page_bufs, 0, pagesize, NULL, bget_one);
 
 	ret = block_write_full_page(page, ext4_get_block, wbc);
 

@@ -1461,13 +1461,12 @@ static int ext4_ordered_writepage(struct page *page,
 	 * and generally junk.
 	 */
 	if (ret == 0) {
-		err = walk_page_buffers(handle, page_bufs, 0, PAGE_CACHE_SIZE,
+		err = walk_page_buffers(handle, page_bufs, 0, pagesize,
 					NULL, jbd2_journal_dirty_data_fn);
 		if (!ret)
 			ret = err;
 	}
-	walk_page_buffers(handle, page_bufs, 0,
-			PAGE_CACHE_SIZE, NULL, bput_one);
+	walk_page_buffers(handle, page_bufs, 0, pagesize, NULL, bput_one);
 	err = ext4_journal_stop(handle);
 	if (!ret)
 		ret = err;

@@ -1519,6 +1518,7 @@ static int ext4_journalled_writepage(struct page *page,
 	handle_t *handle = NULL;
 	int ret = 0;
 	int err;
+	int pagesize = page_cache_size(inode->i_mapping);
 
 	if (ext4_journal_current_handle())
 		goto no_write;

@@ -1535,17 +1535,17 @@ static int ext4_journalled_writepage(struct page *page,
 		 * doesn't seem much point in redirtying the page here.
 		 */
 		ClearPageChecked(page);
-		ret = block_prepare_write(page, 0, PAGE_CACHE_SIZE,
+		ret = block_prepare_write(page, 0, pagesize,
 					ext4_get_block);
 		if (ret != 0) {
 			ext4_journal_stop(handle);
 			goto out_unlock;
 		}
 		ret = walk_page_buffers(handle, page_buffers(page), 0,
-			PAGE_CACHE_SIZE, NULL, do_journal_get_write_access);
+			pagesize, NULL, do_journal_get_write_access);
 
 		err = walk_page_buffers(handle, page_buffers(page), 0,
-				PAGE_CACHE_SIZE, NULL, commit_write_fn);
+				pagesize, NULL, commit_write_fn);
 		if (ret == 0)
 			ret = err;
 		EXT4_I(inode)->i_state |= EXT4_STATE_JDATA;

@@ -1760,8 +1760,8 @@ void ext4_set_aops(struct inode *inode)
 int ext4_block_truncate_page(handle_t *handle, struct page *page,
 		struct address_space *mapping, loff_t from)
 {
-	ext4_fsblk_t index = from >> PAGE_CACHE_SHIFT;
-	unsigned offset = from & (PAGE_CACHE_SIZE-1);
+	ext4_fsblk_t index = page_cache_index(mapping, from);
+	unsigned offset = page_cache_offset(mapping, from);
 	unsigned blocksize, iblock, length, pos;
 	struct inode *inode = mapping->host;
 	struct buffer_head *bh;

@@ -1769,7 +1769,8 @@ int ext4_block_truncate_page(handle_t *handle, struct page *page,
 
 	blocksize = inode->i_sb->s_blocksize;
 	length = blocksize - (offset & (blocksize - 1));
-	iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
+	iblock = index <<
+		(page_cache_shift(mapping) - inode->i_sb->s_blocksize_bits);
 
 	/*
 	 * For "nobh" option,  we can only work if we don't need to

@@ -2249,7 +2250,7 @@ void ext4_truncate(struct inode *inode)
 		page = NULL;
 	} else {
 		page = grab_cache_page(mapping,
-				inode->i_size >> PAGE_CACHE_SHIFT);
+				page_cache_index(mapping, inode->i_size));
 		if (!page)
 			return;
 	}

Index: linux-2.6/fs/reiserfs/file.c
===================================================================
@@ -187,9 +187,11 @@ static int reiserfs_allocate_blocks_for_
 	int curr_block;		// current block used to keep track of unmapped blocks.
 	int i;			// loop counter
 	int itempos;		// position in item
-	unsigned int from = (pos & (PAGE_CACHE_SIZE - 1));	// writing position in
+	struct address_space *mapping = prepared_pages[0]->mapping;
+	unsigned int from = page_cache_offset(mapping, pos);	// writing position in
 	// first page
-	unsigned int to = ((pos + write_bytes - 1) & (PAGE_CACHE_SIZE - 1)) + 1;	/* last modified byte offset in last page */
+	unsigned int to = page_cache_offset(mapping, pos + write_bytes - 1)  + 1;
+					/* last modified byte offset in last page */
 	__u64 hole_size;	// amount of blocks for a file hole, if it needed to be created.
 	int modifying_this_item = 0;	// Flag for items traversal code to keep track
 	// of the fact that we already prepared

@@ -731,19 +733,22 @@ static int reiserfs_copy_from_user_to_fi
 	long page_fault = 0;	// status of copy_from_user.
 	int i;			// loop counter.
 	int offset;		// offset in page
+	struct address_space *mapping = prepared_pages[0]->mapping;
 
-	for (i = 0, offset = (pos & (PAGE_CACHE_SIZE - 1)); i < num_pages;
+	for (i = 0, offset = page_cache_offset(mapping, pos); i < num_pages;
 	     i++, offset = 0) {
-		size_t count = min_t(size_t, PAGE_CACHE_SIZE - offset, write_bytes);	// How much of bytes to write to this page
+		size_t count = min_t(size_t, page_cache_size(mapping) - offset,
+			write_bytes);	// How much of bytes to write to this page
 		struct page *page = prepared_pages[i];	// Current page we process.
 
 		fault_in_pages_readable(buf, count);
 
 		/* Copy data from userspace to the current page */
 		kmap(page);
-		page_fault = __copy_from_user(page_address(page) + offset, buf, count);	// Copy the data.
+		page_fault = __copy_from_user(page_address(page) + offset, buf, count);
+					// Copy the data.
 		/* Flush processor's dcache for this page */
-		flush_dcache_page(page);
+		flush_mapping_page(page);
 		kunmap(page);
 		buf += count;
 		write_bytes -= count;

@@ -763,11 +768,12 @@ int reiserfs_commit_page(struct inode *i
 	int partial = 0;
 	unsigned blocksize;
 	struct buffer_head *bh, *head;
-	unsigned long i_size_index = inode->i_size >> PAGE_CACHE_SHIFT;
+	unsigned long i_size_index =
+		page_cache_offset(inode->i_mapping, inode->i_size);
 	int new;
 	int logit = reiserfs_file_data_log(inode);
 	struct super_block *s = inode->i_sb;
-	int bh_per_page = PAGE_CACHE_SIZE / s->s_blocksize;
+	int bh_per_page = page_cache_size(inode->i_mapping) / s->s_blocksize;
 	struct reiserfs_transaction_handle th;
 	int ret = 0;
 

@@ -839,10 +845,11 @@ static int reiserfs_submit_file_region_f
 	int offset;		// Writing offset in page.
 	int orig_write_bytes = write_bytes;
 	int sd_update = 0;
+	struct address_space *mapping = inode->i_mapping;
 
-	for (i = 0, offset = (pos & (PAGE_CACHE_SIZE - 1)); i < num_pages;
+	for (i = 0, offset = page_cache_offset(mapping, pos); i < num_pages;
 	     i++, offset = 0) {
-		int count = min_t(int, PAGE_CACHE_SIZE - offset, write_bytes);	// How much of bytes to write to this page
+		int count = min_t(int, page_cache_size(mapping) - offset, write_bytes);	// How much of bytes to write to this page
 		struct page *page = prepared_pages[i];	// Current page we process.
 
 		status =

@@ -985,12 +992,12 @@ static int reiserfs_prepare_file_region_
     )
 {
 	int res = 0;		// Return values of different functions we call.
-	unsigned long index = pos >> PAGE_CACHE_SHIFT;	// Offset in file in pages.
-	int from = (pos & (PAGE_CACHE_SIZE - 1));	// Writing offset in first page
-	int to = ((pos + write_bytes - 1) & (PAGE_CACHE_SIZE - 1)) + 1;
+	struct address_space *mapping = inode->i_mapping;	// Pages are mapped here.
+	unsigned long index = page_cache_index(mapping, pos);	// Offset in file in pages.
+	int from = page_cache_offset(mapping, pos);	// Writing offset in first page
+	int to = page_cache_offset(mapping, pos + write_bytes - 1) + 1;
 	/* offset of last modified byte in last
 	   page */
-	struct address_space *mapping = inode->i_mapping;	// Pages are mapped here.
 	int i;			// Simple counter
 	int blocks = 0;		/* Return value (blocks that should be allocated) */
 	struct buffer_head *bh, *head;	// Current bufferhead and first bufferhead

@@ -1041,30 +1048,31 @@ static int reiserfs_prepare_file_region_
 		/* These are full-overwritten pages so we count all the blocks in
 		   these pages are counted as needed to be allocated */
 		blocks =
-		    (num_pages - 2) << (PAGE_CACHE_SHIFT - inode->i_blkbits);
+		    (num_pages - 2) << (page_cache_shift(mapping) - inode->i_blkbits);
 
 	/* count blocks needed for first page (possibly partially written) */
-	blocks += ((PAGE_CACHE_SIZE - from) >> inode->i_blkbits) + !!(from & (inode->i_sb->s_blocksize - 1));	/* roundup */
+	blocks += ((page_cache_size(mapping) - from) >> inode->i_blkbits)
+		+ !!(from & (inode->i_sb->s_blocksize - 1));	/* roundup */
 
 	/* Now we account for last page. If last page == first page (we
 	   overwrite only one page), we substract all the blocks past the
 	   last writing position in a page out of already calculated number
 	   of blocks */
-	blocks += ((num_pages > 1) << (PAGE_CACHE_SHIFT - inode->i_blkbits)) -
-	    ((PAGE_CACHE_SIZE - to) >> inode->i_blkbits);
+	blocks += ((num_pages > 1) << (page_cache_shift(mapping) - inode->i_blkbits)) -
+	    ((page_cache_size(mapping) - to) >> inode->i_blkbits);
 	/* Note how we do not roundup here since partial blocks still
 	   should be allocated */
 
 	/* Now if all the write area lies past the file end, no point in
 	   maping blocks, since there is none, so we just zero out remaining
 	   parts of first and last pages in write area (if needed) */
-	if ((pos & ~((loff_t) PAGE_CACHE_SIZE - 1)) > inode->i_size) {
+	if (page_cache_offset(mapping, pos) > inode->i_size) {
 		if (from != 0)		/* First page needs to be partially zeroed */
 			zero_user(prepared_pages[0], 0, from);
 
-		if (to != PAGE_CACHE_SIZE)	/* Last page needs to be partially zeroed */
+		if (to != page_cache_size(mapping))	/* Last page needs to be partially zeroed */
 			zero_user_segment(prepared_pages[num_pages-1], to,
-					PAGE_CACHE_SIZE);
+					page_cache_size(mapping));
 
 		/* Since all blocks are new - use already calculated value */
 		return blocks;

@@ -1201,8 +1209,8 @@ static int reiserfs_prepare_file_region_
 
 	/* Last page, see if it is not uptodate, or if the last page is past the end of the file. */
 	if (!PageUptodate(prepared_pages[num_pages - 1]) ||
-	    ((pos + write_bytes) >> PAGE_CACHE_SHIFT) >
-	    (inode->i_size >> PAGE_CACHE_SHIFT)) {
+	    page_cache_index(mapping, pos + write_bytes) >
+	    page_cache_index(mapping, inode->i_size)) {
 		head = page_buffers(prepared_pages[num_pages - 1]);
 
 		/* for each buffer in page */

@@ -1292,6 +1300,7 @@ static ssize_t reiserfs_file_write(struc
 	   locked pages in array for now */
 	struct page *prepared_pages[REISERFS_WRITE_PAGES_AT_A_TIME];
 	struct reiserfs_transaction_handle th;
+	struct address_space *mapping = inode->i_mapping;
 	th.t_trans_id = 0;
 
 	/* If a filesystem is converted from 3.5 to 3.6, we'll have v3.5 items

@@ -1358,10 +1367,10 @@ static ssize_t reiserfs_file_write(struc
 		size_t blocks_to_allocate;	/* how much blocks we need to allocate for this iteration */
 
 		/*  (pos & (PAGE_CACHE_SIZE-1)) is an idiom for offset into a page of pos */
-		num_pages = !!((pos + count) & (PAGE_CACHE_SIZE - 1)) +	/* round up partial
+		num_pages = !!(page_cache_offset(mapping, pos + count)) +	/* round up partial
 									   pages */
 		    ((count +
-		      (pos & (PAGE_CACHE_SIZE - 1))) >> PAGE_CACHE_SHIFT);
+		      (pos & (page_cache_size(mapping) - 1))) >> page_cache_shift(mapping));
 		/* convert size to amount of
 		   pages */
 		reiserfs_write_lock(inode->i_sb);

@@ -1374,8 +1383,8 @@ static ssize_t reiserfs_file_write(struc
 			    min_t(size_t, REISERFS_WRITE_PAGES_AT_A_TIME,
 				  reiserfs_can_fit_pages(inode->i_sb));
 			/* Also we should not forget to set size in bytes accordingly */
-			write_bytes = (num_pages << PAGE_CACHE_SHIFT) -
-			    (pos & (PAGE_CACHE_SIZE - 1));
+			write_bytes = (num_pages << page_cache_shift(mapping)) -
+			page_cache_offset(mapping, pos);
 			/* If position is not on the
 			   start of the page, we need
 			   to substract the offset

@@ -1387,7 +1396,7 @@ static ssize_t reiserfs_file_write(struc
 		   we still have the space to write the blocks to */
 		reiserfs_claim_blocks_to_be_allocated(inode->i_sb,
 						      num_pages <<
-						      (PAGE_CACHE_SHIFT -
+						      (page_cache_shift(mapping) -
 						       inode->i_blkbits));
 		reiserfs_write_unlock(inode->i_sb);
 

@@ -1412,7 +1421,7 @@ static ssize_t reiserfs_file_write(struc
 			// No blocks were claimed before, so do it now.
 			reiserfs_claim_blocks_to_be_allocated(inode->i_sb,
 							      1 <<
-							      (PAGE_CACHE_SHIFT
+							      (page_cache_shift(mapping)
 							       -
 							       inode->
 							       i_blkbits));

@@ -1429,7 +1438,7 @@ static ssize_t reiserfs_file_write(struc
 		if (res < 0) {
 			reiserfs_release_claimed_blocks(inode->i_sb,
 							num_pages <<
-							(PAGE_CACHE_SHIFT -
+							(page_cache_shift(mapping) -
 							 inode->i_blkbits));
 			break;
 		}

@@ -1439,7 +1448,7 @@ static ssize_t reiserfs_file_write(struc
 		/* First we correct our estimate of how many blocks we need */
 		reiserfs_release_claimed_blocks(inode->i_sb,
 						(num_pages <<
-						 (PAGE_CACHE_SHIFT -
+						 (page_cache_shift(mapping) -
 						  inode->i_sb->
 						  s_blocksize_bits)) -
 						blocks_to_allocate);

Index: linux-2.6/fs/reiserfs/inode.c
===================================================================
@@ -336,7 +336,8 @@ static int _get_block_create_0(struct in
 		goto finished;
 	}
 	// read file tail into part of page
-	offset = (cpu_key_k_offset(&key) - 1) & (PAGE_CACHE_SIZE - 1);
+	offset = page_cache_offset(inode->i_mapping,
+				cpu_key_k_offset(&key) - 1);
 	fs_gen = get_generation(inode->i_sb);
 	copy_item_head(&tmp_ih, ih);
 

@@ -522,10 +523,10 @@ static int convert_tail_for_hole(struct 
 		return -EIO;
 
 	/* always try to read until the end of the block */
-	tail_start = tail_offset & (PAGE_CACHE_SIZE - 1);
+	tail_start = page_cache_offset(inode->i_mapping, tail_offset);
 	tail_end = (tail_start | (bh_result->b_size - 1)) + 1;
 
-	index = tail_offset >> PAGE_CACHE_SHIFT;
+	index = page_cache_index(inode->i_mapping, tail_offset);
 	/* hole_page can be zero in case of direct_io, we are sure
 	   that we cannot get here if we write with O_DIRECT into
 	   tail page */

@@ -2007,11 +2008,13 @@ static int grab_tail_page(struct inode *
 	/* we want the page with the last byte in the file,
 	 ** not the page that will hold the next byte for appending
 	 */
-	unsigned long index = (p_s_inode->i_size - 1) >> PAGE_CACHE_SHIFT;
+	unsigned long index = page_cache_index(p_s_inode->i_mapping,
+						p_s_inode->i_size - 1);
 	unsigned long pos = 0;
 	unsigned long start = 0;
 	unsigned long blocksize = p_s_inode->i_sb->s_blocksize;
-	unsigned long offset = (p_s_inode->i_size) & (PAGE_CACHE_SIZE - 1);
+	unsigned long offset = page_cache_index(p_s_inode->i_mapping,
+							p_s_inode->i_size);
 	struct buffer_head *bh;
 	struct buffer_head *head;
 	struct page *page;

@@ -2083,7 +2086,8 @@ int reiserfs_truncate_file(struct inode 
 {
 	struct reiserfs_transaction_handle th;
 	/* we want the offset for the first byte after the end of the file */
-	unsigned long offset = p_s_inode->i_size & (PAGE_CACHE_SIZE - 1);
+	unsigned long offset = page_cache_offset(p_s_inode->i_mapping,
+							p_s_inode->i_size);
 	unsigned blocksize = p_s_inode->i_sb->s_blocksize;
 	unsigned length;
 	struct page *page = NULL;

@@ -2232,7 +2236,7 @@ static int map_block_for_writepage(struc
 	} else if (is_direct_le_ih(ih)) {
 		char *p;
 		p = page_address(bh_result->b_page);
-		p += (byte_offset - 1) & (PAGE_CACHE_SIZE - 1);
+		p += page_cache_offset(inode->i_mapping, byte_offset - 1);
 		copy_size = ih_item_len(ih) - pos_in_item;
 
 		fs_gen = get_generation(inode->i_sb);

@@ -2331,7 +2335,8 @@ static int reiserfs_write_full_page(stru
 				    struct writeback_control *wbc)
 {
 	struct inode *inode = page->mapping->host;
-	unsigned long end_index = inode->i_size >> PAGE_CACHE_SHIFT;
+	unsigned long end_index = page_cache_index(inode->i_mapping,
+							inode->i_size);
 	int error = 0;
 	unsigned long block;
 	sector_t last_block;