mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros

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>;

 - <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();

This patch contains automated changes generated with coccinelle using
script below.  For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach.  I'll
fix them manually in a separate patch.  Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 6 insertions, 6 deletions

diff --git a/fs/ntfs/index.c b/fs/ntfs/index.c
index 096c135691ae..02a83a46ead2 100644
--- a/fs/ntfs/index.c
+++ b/fs/ntfs/index.c
@@ -276,7 +276,7 @@ descend_into_child_node:
 	 * disk if necessary.
 	 */
 	page = ntfs_map_page(ia_mapping, vcn <<
-			idx_ni->itype.index.vcn_size_bits >> PAGE_CACHE_SHIFT);
+			idx_ni->itype.index.vcn_size_bits >> PAGE_SHIFT);
 	if (IS_ERR(page)) {
 		ntfs_error(sb, "Failed to map index page, error %ld.",
 				-PTR_ERR(page));
@@ -288,9 +288,9 @@ descend_into_child_node:
 fast_descend_into_child_node:
 	/* Get to the index allocation block. */
 	ia = (INDEX_ALLOCATION*)(kaddr + ((vcn <<
-			idx_ni->itype.index.vcn_size_bits) & ~PAGE_CACHE_MASK));
+			idx_ni->itype.index.vcn_size_bits) & ~PAGE_MASK));
 	/* Bounds checks. */
-	if ((u8*)ia < kaddr || (u8*)ia > kaddr + PAGE_CACHE_SIZE) {
+	if ((u8*)ia < kaddr || (u8*)ia > kaddr + PAGE_SIZE) {
 		ntfs_error(sb, "Out of bounds check failed.  Corrupt inode "
 				"0x%lx or driver bug.", idx_ni->mft_no);
 		goto unm_err_out;
@@ -323,7 +323,7 @@ fast_descend_into_child_node:
 		goto unm_err_out;
 	}
 	index_end = (u8*)ia + idx_ni->itype.index.block_size;
-	if (index_end > kaddr + PAGE_CACHE_SIZE) {
+	if (index_end > kaddr + PAGE_SIZE) {
 		ntfs_error(sb, "Index buffer (VCN 0x%llx) of inode 0x%lx "
 				"crosses page boundary.  Impossible!  Cannot "
 				"access!  This is probably a bug in the "
@@ -427,9 +427,9 @@ ia_done:
 		 * the mapped page.
 		 */
 		if (old_vcn << vol->cluster_size_bits >>
-				PAGE_CACHE_SHIFT == vcn <<
+				PAGE_SHIFT == vcn <<
 				vol->cluster_size_bits >>
-				PAGE_CACHE_SHIFT)
+				PAGE_SHIFT)
 			goto fast_descend_into_child_node;
 		unlock_page(page);
 		ntfs_unmap_page(page);