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, 24 insertions, 24 deletions

diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index 1581240a7ca0..ce5dc4f92935 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -234,7 +234,7 @@ int ocfs2_read_inline_data(struct inode *inode, struct page *page,
 
 	size = i_size_read(inode);
 
-	if (size > PAGE_CACHE_SIZE ||
+	if (size > PAGE_SIZE ||
 	    size > ocfs2_max_inline_data_with_xattr(inode->i_sb, di)) {
 		ocfs2_error(inode->i_sb,
 			    "Inode %llu has with inline data has bad size: %Lu\n",
@@ -247,7 +247,7 @@ int ocfs2_read_inline_data(struct inode *inode, struct page *page,
 	if (size)
 		memcpy(kaddr, di->id2.i_data.id_data, size);
 	/* Clear the remaining part of the page */
-	memset(kaddr + size, 0, PAGE_CACHE_SIZE - size);
+	memset(kaddr + size, 0, PAGE_SIZE - size);
 	flush_dcache_page(page);
 	kunmap_atomic(kaddr);
 
@@ -282,7 +282,7 @@ static int ocfs2_readpage(struct file *file, struct page *page)
 {
 	struct inode *inode = page->mapping->host;
 	struct ocfs2_inode_info *oi = OCFS2_I(inode);
-	loff_t start = (loff_t)page->index << PAGE_CACHE_SHIFT;
+	loff_t start = (loff_t)page->index << PAGE_SHIFT;
 	int ret, unlock = 1;
 
 	trace_ocfs2_readpage((unsigned long long)oi->ip_blkno,
@@ -385,7 +385,7 @@ static int ocfs2_readpages(struct file *filp, struct address_space *mapping,
 	 * drop out in that case as it's not worth handling here.
 	 */
 	last = list_entry(pages->prev, struct page, lru);
-	start = (loff_t)last->index << PAGE_CACHE_SHIFT;
+	start = (loff_t)last->index << PAGE_SHIFT;
 	if (start >= i_size_read(inode))
 		goto out_unlock;
 
@@ -511,12 +511,12 @@ static void ocfs2_figure_cluster_boundaries(struct ocfs2_super *osb,
 					    unsigned int *start,
 					    unsigned int *end)
 {
-	unsigned int cluster_start = 0, cluster_end = PAGE_CACHE_SIZE;
+	unsigned int cluster_start = 0, cluster_end = PAGE_SIZE;
 
-	if (unlikely(PAGE_CACHE_SHIFT > osb->s_clustersize_bits)) {
+	if (unlikely(PAGE_SHIFT > osb->s_clustersize_bits)) {
 		unsigned int cpp;
 
-		cpp = 1 << (PAGE_CACHE_SHIFT - osb->s_clustersize_bits);
+		cpp = 1 << (PAGE_SHIFT - osb->s_clustersize_bits);
 
 		cluster_start = cpos % cpp;
 		cluster_start = cluster_start << osb->s_clustersize_bits;
@@ -687,10 +687,10 @@ next_bh:
 #if (PAGE_CACHE_SIZE >= OCFS2_MAX_CLUSTERSIZE)
 #define OCFS2_MAX_CTXT_PAGES	1
 #else
-#define OCFS2_MAX_CTXT_PAGES	(OCFS2_MAX_CLUSTERSIZE / PAGE_CACHE_SIZE)
+#define OCFS2_MAX_CTXT_PAGES	(OCFS2_MAX_CLUSTERSIZE / PAGE_SIZE)
 #endif
 
-#define OCFS2_MAX_CLUSTERS_PER_PAGE	(PAGE_CACHE_SIZE / OCFS2_MIN_CLUSTERSIZE)
+#define OCFS2_MAX_CLUSTERS_PER_PAGE	(PAGE_SIZE / OCFS2_MIN_CLUSTERSIZE)
 
 struct ocfs2_unwritten_extent {
 	struct list_head	ue_node;
@@ -785,7 +785,7 @@ void ocfs2_unlock_and_free_pages(struct page **pages, int num_pages)
 		if (pages[i]) {
 			unlock_page(pages[i]);
 			mark_page_accessed(pages[i]);
-			page_cache_release(pages[i]);
+			put_page(pages[i]);
 		}
 	}
 }
@@ -808,7 +808,7 @@ static void ocfs2_unlock_pages(struct ocfs2_write_ctxt *wc)
 			}
 		}
 		mark_page_accessed(wc->w_target_page);
-		page_cache_release(wc->w_target_page);
+		put_page(wc->w_target_page);
 	}
 	ocfs2_unlock_and_free_pages(wc->w_pages, wc->w_num_pages);
 }
@@ -857,7 +857,7 @@ static int ocfs2_alloc_write_ctxt(struct ocfs2_write_ctxt **wcp,
 	wc->w_di_bh = di_bh;
 	wc->w_type = type;
 
-	if (unlikely(PAGE_CACHE_SHIFT > osb->s_clustersize_bits))
+	if (unlikely(PAGE_SHIFT > osb->s_clustersize_bits))
 		wc->w_large_pages = 1;
 	else
 		wc->w_large_pages = 0;
@@ -920,7 +920,7 @@ static void ocfs2_write_failure(struct inode *inode,
 				loff_t user_pos, unsigned user_len)
 {
 	int i;
-	unsigned from = user_pos & (PAGE_CACHE_SIZE - 1),
+	unsigned from = user_pos & (PAGE_SIZE - 1),
 		to = user_pos + user_len;
 	struct page *tmppage;
 
@@ -960,7 +960,7 @@ static int ocfs2_prepare_page_for_write(struct inode *inode, u64 *p_blkno,
 			(page_offset(page) <= user_pos));
 
 	if (page == wc->w_target_page) {
-		map_from = user_pos & (PAGE_CACHE_SIZE - 1);
+		map_from = user_pos & (PAGE_SIZE - 1);
 		map_to = map_from + user_len;
 
 		if (new)
@@ -1034,7 +1034,7 @@ static int ocfs2_grab_pages_for_write(struct address_space *mapping,
 	struct inode *inode = mapping->host;
 	loff_t last_byte;
 
-	target_index = user_pos >> PAGE_CACHE_SHIFT;
+	target_index = user_pos >> PAGE_SHIFT;
 
 	/*
 	 * Figure out how many pages we'll be manipulating here. For
@@ -1053,14 +1053,14 @@ static int ocfs2_grab_pages_for_write(struct address_space *mapping,
 		 */
 		last_byte = max(user_pos + user_len, i_size_read(inode));
 		BUG_ON(last_byte < 1);
-		end_index = ((last_byte - 1) >> PAGE_CACHE_SHIFT) + 1;
+		end_index = ((last_byte - 1) >> PAGE_SHIFT) + 1;
 		if ((start + wc->w_num_pages) > end_index)
 			wc->w_num_pages = end_index - start;
 	} else {
 		wc->w_num_pages = 1;
 		start = target_index;
 	}
-	end_index = (user_pos + user_len - 1) >> PAGE_CACHE_SHIFT;
+	end_index = (user_pos + user_len - 1) >> PAGE_SHIFT;
 
 	for(i = 0; i < wc->w_num_pages; i++) {
 		index = start + i;
@@ -1082,7 +1082,7 @@ static int ocfs2_grab_pages_for_write(struct address_space *mapping,
 				goto out;
 			}
 
-			page_cache_get(mmap_page);
+			get_page(mmap_page);
 			wc->w_pages[i] = mmap_page;
 			wc->w_target_locked = true;
 		} else if (index >= target_index && index <= end_index &&
@@ -1272,7 +1272,7 @@ static void ocfs2_set_target_boundaries(struct ocfs2_super *osb,
 {
 	struct ocfs2_write_cluster_desc *desc;
 
-	wc->w_target_from = pos & (PAGE_CACHE_SIZE - 1);
+	wc->w_target_from = pos & (PAGE_SIZE - 1);
 	wc->w_target_to = wc->w_target_from + len;
 
 	if (alloc == 0)
@@ -1309,7 +1309,7 @@ static void ocfs2_set_target_boundaries(struct ocfs2_super *osb,
 							&wc->w_target_to);
 	} else {
 		wc->w_target_from = 0;
-		wc->w_target_to = PAGE_CACHE_SIZE;
+		wc->w_target_to = PAGE_SIZE;
 	}
 }
 
@@ -1981,7 +1981,7 @@ int ocfs2_write_end_nolock(struct address_space *mapping,
 			   struct page *page, void *fsdata)
 {
 	int i, ret;
-	unsigned from, to, start = pos & (PAGE_CACHE_SIZE - 1);
+	unsigned from, to, start = pos & (PAGE_SIZE - 1);
 	struct inode *inode = mapping->host;
 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 	struct ocfs2_write_ctxt *wc = fsdata;
@@ -2027,8 +2027,8 @@ int ocfs2_write_end_nolock(struct address_space *mapping,
 			from = wc->w_target_from;
 			to = wc->w_target_to;
 
-			BUG_ON(from > PAGE_CACHE_SIZE ||
-			       to > PAGE_CACHE_SIZE ||
+			BUG_ON(from > PAGE_SIZE ||
+			       to > PAGE_SIZE ||
 			       to < from);
 		} else {
 			/*
@@ -2037,7 +2037,7 @@ int ocfs2_write_end_nolock(struct address_space *mapping,
 			 * to flush their entire range.
 			 */
 			from = 0;
-			to = PAGE_CACHE_SIZE;
+			to = PAGE_SIZE;
 		}
 
 		if (page_has_buffers(tmppage)) {