[PATCH 62/71] udf: get rid of PAGE_CACHE_* and page_cache_{get,release} macros

[Kirill A. Shutemov]

PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago
with promise that one day it will be possible to implement page cache with
bigger chunks than PAGE_SIZE.

This promise never materialized. And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_*
or PAGE_* constant should be used in a particular case, especially on the
border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special. They are not.

The changes are pretty straight-forward:

 - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

 - page_cache_get() -> get_page();

 - page_cache_release() -> put_page();

Signed-off-by: Kirill A. Shutemov <kirill.shute...@linux.intel.com>
Cc: Jan Kara <j...@suse.com>
---
 fs/udf/file.c  | 6 +++---
 fs/udf/inode.c | 4 ++--
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/fs/udf/file.c b/fs/udf/file.c
index 1af98963d860..877ba1c9b461 100644
--- a/fs/udf/file.c
+++ b/fs/udf/file.c
@@ -46,7 +46,7 @@ static void __udf_adinicb_readpage(struct page *page)
 
        kaddr = kmap(page);
        memcpy(kaddr, iinfo->i_ext.i_data + iinfo->i_lenEAttr, inode->i_size);
-       memset(kaddr + inode->i_size, 0, PAGE_CACHE_SIZE - inode->i_size);
+       memset(kaddr + inode->i_size, 0, PAGE_SIZE - inode->i_size);
        flush_dcache_page(page);
        SetPageUptodate(page);
        kunmap(page);
@@ -87,14 +87,14 @@ static int udf_adinicb_write_begin(struct file *file,
 {
        struct page *page;
 
-       if (WARN_ON_ONCE(pos >= PAGE_CACHE_SIZE))
+       if (WARN_ON_ONCE(pos >= PAGE_SIZE))
                return -EIO;
        page = grab_cache_page_write_begin(mapping, 0, flags);
        if (!page)
                return -ENOMEM;
        *pagep = page;
 
-       if (!PageUptodate(page) && len != PAGE_CACHE_SIZE)
+       if (!PageUptodate(page) && len != PAGE_SIZE)
                __udf_adinicb_readpage(page);
        return 0;
 }
diff --git a/fs/udf/inode.c b/fs/udf/inode.c
index 166d3ed32c39..2dc461eeb415 100644
--- a/fs/udf/inode.c
+++ b/fs/udf/inode.c
@@ -287,7 +287,7 @@ int udf_expand_file_adinicb(struct inode *inode)
        if (!PageUptodate(page)) {
                kaddr = kmap(page);
                memset(kaddr + iinfo->i_lenAlloc, 0x00,
-                      PAGE_CACHE_SIZE - iinfo->i_lenAlloc);
+                      PAGE_SIZE - iinfo->i_lenAlloc);
                memcpy(kaddr, iinfo->i_ext.i_data + iinfo->i_lenEAttr,
                        iinfo->i_lenAlloc);
                flush_dcache_page(page);
@@ -319,7 +319,7 @@ int udf_expand_file_adinicb(struct inode *inode)
                inode->i_data.a_ops = &udf_adinicb_aops;
                up_write(&iinfo->i_data_sem);
        }
-       page_cache_release(page);
+       put_page(page);
        mark_inode_dirty(inode);
 
        return err;
-- 
2.7.0