[PATCH 35/71] freevxfs: 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: Christoph Hellwig <h...@infradead.org>
---
 fs/freevxfs/vxfs_immed.c  |  4 ++--
 fs/freevxfs/vxfs_lookup.c | 12 ++++++------
 fs/freevxfs/vxfs_subr.c   |  2 +-
 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);
 }
 
 /**
-- 
2.7.0