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>

3 files changed, 9 insertions, 9 deletions

diff --git a/fs/freevxfs/vxfs_immed.c b/fs/freevxfs/vxfs_immed.c
index cb84f0fcc72a..bfc780c682fb 100644
--- a/fs/freevxfs/vxfs_immed.c
+++ b/fs/freevxfs/vxfs_immed.c
@@ -66,11 +66,11 @@ static int
 vxfs_immed_readpage(struct file *fp, struct page *pp)
 {
 	struct vxfs_inode_info	*vip = VXFS_INO(pp->mapping->host);
-	u_int64_t	offset = (u_int64_t)pp->index << PAGE_CACHE_SHIFT;
+	u_int64_t	offset = (u_int64_t)pp->index << PAGE_SHIFT;
 	caddr_t		kaddr;
 
 	kaddr = kmap(pp);
-	memcpy(kaddr, vip->vii_immed.vi_immed + offset, PAGE_CACHE_SIZE);
+	memcpy(kaddr, vip->vii_immed.vi_immed + offset, PAGE_SIZE);
 	kunmap(pp);
 	
 	flush_dcache_page(pp);
diff --git a/fs/freevxfs/vxfs_lookup.c b/fs/freevxfs/vxfs_lookup.c
index 1cff72df0389..a49e0cfbb686 100644
--- a/fs/freevxfs/vxfs_lookup.c
+++ b/fs/freevxfs/vxfs_lookup.c
@@ -45,7 +45,7 @@
 /*
  * Number of VxFS blocks per page.
  */
-#define VXFS_BLOCK_PER_PAGE(sbp)  ((PAGE_CACHE_SIZE / (sbp)->s_blocksize))
+#define VXFS_BLOCK_PER_PAGE(sbp)  ((PAGE_SIZE / (sbp)->s_blocksize))
 
 
 static struct dentry *	vxfs_lookup(struct inode *, struct dentry *, unsigned int);
@@ -175,7 +175,7 @@ vxfs_inode_by_name(struct inode *dip, struct dentry *dp)
 	if (de) {
 		ino = de->d_ino;
 		kunmap(pp);
-		page_cache_release(pp);
+		put_page(pp);
 	}
 	
 	return (ino);
@@ -255,8 +255,8 @@ vxfs_readdir(struct file *fp, struct dir_context *ctx)
 	nblocks = dir_blocks(ip);
 	pblocks = VXFS_BLOCK_PER_PAGE(sbp);
 
-	page = pos >> PAGE_CACHE_SHIFT;
-	offset = pos & ~PAGE_CACHE_MASK;
+	page = pos >> PAGE_SHIFT;
+	offset = pos & ~PAGE_MASK;
 	block = (u_long)(pos >> sbp->s_blocksize_bits) % pblocks;
 
 	for (; page < npages; page++, block = 0) {
@@ -289,7 +289,7 @@ vxfs_readdir(struct file *fp, struct dir_context *ctx)
 					continue;
 
 				offset = (char *)de - kaddr;
-				ctx->pos = ((page << PAGE_CACHE_SHIFT) | offset) + 2;
+				ctx->pos = ((page << PAGE_SHIFT) | offset) + 2;
 				if (!dir_emit(ctx, de->d_name, de->d_namelen,
 					de->d_ino, DT_UNKNOWN)) {
 					vxfs_put_page(pp);
@@ -301,6 +301,6 @@ vxfs_readdir(struct file *fp, struct dir_context *ctx)
 		vxfs_put_page(pp);
 		offset = 0;
 	}
-	ctx->pos = ((page << PAGE_CACHE_SHIFT) | offset) + 2;
+	ctx->pos = ((page << PAGE_SHIFT) | offset) + 2;
 	return 0;
 }
diff --git a/fs/freevxfs/vxfs_subr.c b/fs/freevxfs/vxfs_subr.c
index 5d318c44f855..e806694d4145 100644
--- a/fs/freevxfs/vxfs_subr.c
+++ b/fs/freevxfs/vxfs_subr.c
@@ -50,7 +50,7 @@ inline void
 vxfs_put_page(struct page *pp)
 {
 	kunmap(pp);
-	page_cache_release(pp);
+	put_page(pp);
 }
 
 /**