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, 26 insertions, 26 deletions

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index e5c762b..53fec08 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -223,7 +223,7 @@ int f2fs_submit_page_bio(struct f2fs_io_info *fio)
 	/* Allocate a new bio */
 	bio = __bio_alloc(fio->sbi, fio->new_blkaddr, 1, is_read_io(fio->rw));
 
-	if (bio_add_page(bio, page, PAGE_CACHE_SIZE, 0) < PAGE_CACHE_SIZE) {
+	if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
 		bio_put(bio);
 		return -EFAULT;
 	}
@@ -265,8 +265,8 @@ alloc_new:
 
 	bio_page = fio->encrypted_page ? fio->encrypted_page : fio->page;
 
-	if (bio_add_page(io->bio, bio_page, PAGE_CACHE_SIZE, 0) <
-							PAGE_CACHE_SIZE) {
+	if (bio_add_page(io->bio, bio_page, PAGE_SIZE, 0) <
+							PAGE_SIZE) {
 		__submit_merged_bio(io);
 		goto alloc_new;
 	}
@@ -406,7 +406,7 @@ got_it:
 	 * see, f2fs_add_link -> get_new_data_page -> init_inode_metadata.
 	 */
 	if (dn.data_blkaddr == NEW_ADDR) {
-		zero_user_segment(page, 0, PAGE_CACHE_SIZE);
+		zero_user_segment(page, 0, PAGE_SIZE);
 		SetPageUptodate(page);
 		unlock_page(page);
 		return page;
@@ -517,7 +517,7 @@ struct page *get_new_data_page(struct inode *inode,
 		goto got_it;
 
 	if (dn.data_blkaddr == NEW_ADDR) {
-		zero_user_segment(page, 0, PAGE_CACHE_SIZE);
+		zero_user_segment(page, 0, PAGE_SIZE);
 		SetPageUptodate(page);
 	} else {
 		f2fs_put_page(page, 1);
@@ -530,8 +530,8 @@ struct page *get_new_data_page(struct inode *inode,
 	}
 got_it:
 	if (new_i_size && i_size_read(inode) <
-				((loff_t)(index + 1) << PAGE_CACHE_SHIFT)) {
-		i_size_write(inode, ((loff_t)(index + 1) << PAGE_CACHE_SHIFT));
+				((loff_t)(index + 1) << PAGE_SHIFT)) {
+		i_size_write(inode, ((loff_t)(index + 1) << PAGE_SHIFT));
 		/* Only the directory inode sets new_i_size */
 		set_inode_flag(F2FS_I(inode), FI_UPDATE_DIR);
 	}
@@ -570,9 +570,9 @@ alloc:
 	/* update i_size */
 	fofs = start_bidx_of_node(ofs_of_node(dn->node_page), dn->inode) +
 							dn->ofs_in_node;
-	if (i_size_read(dn->inode) < ((loff_t)(fofs + 1) << PAGE_CACHE_SHIFT))
+	if (i_size_read(dn->inode) < ((loff_t)(fofs + 1) << PAGE_SHIFT))
 		i_size_write(dn->inode,
-				((loff_t)(fofs + 1) << PAGE_CACHE_SHIFT));
+				((loff_t)(fofs + 1) << PAGE_SHIFT));
 	return 0;
 }
 
@@ -971,7 +971,7 @@ got_it:
 				goto confused;
 			}
 		} else {
-			zero_user_segment(page, 0, PAGE_CACHE_SIZE);
+			zero_user_segment(page, 0, PAGE_SIZE);
 			SetPageUptodate(page);
 			unlock_page(page);
 			goto next_page;
@@ -1021,7 +1021,7 @@ submit_and_realloc:
 		goto next_page;
 set_error_page:
 		SetPageError(page);
-		zero_user_segment(page, 0, PAGE_CACHE_SIZE);
+		zero_user_segment(page, 0, PAGE_SIZE);
 		unlock_page(page);
 		goto next_page;
 confused:
@@ -1032,7 +1032,7 @@ confused:
 		unlock_page(page);
 next_page:
 		if (pages)
-			page_cache_release(page);
+			put_page(page);
 	}
 	BUG_ON(pages && !list_empty(pages));
 	if (bio)
@@ -1136,7 +1136,7 @@ static int f2fs_write_data_page(struct page *page,
 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 	loff_t i_size = i_size_read(inode);
 	const pgoff_t end_index = ((unsigned long long) i_size)
-							>> PAGE_CACHE_SHIFT;
+							>> PAGE_SHIFT;
 	unsigned offset = 0;
 	bool need_balance_fs = false;
 	int err = 0;
@@ -1157,11 +1157,11 @@ static int f2fs_write_data_page(struct page *page,
 	 * If the offset is out-of-range of file size,
 	 * this page does not have to be written to disk.
 	 */
-	offset = i_size & (PAGE_CACHE_SIZE - 1);
+	offset = i_size & (PAGE_SIZE - 1);
 	if ((page->index >= end_index + 1) || !offset)
 		goto out;
 
-	zero_user_segment(page, offset, PAGE_CACHE_SIZE);
+	zero_user_segment(page, offset, PAGE_SIZE);
 write:
 	if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
 		goto redirty_out;
@@ -1267,8 +1267,8 @@ next:
 			cycled = 0;
 		end = -1;
 	} else {
-		index = wbc->range_start >> PAGE_CACHE_SHIFT;
-		end = wbc->range_end >> PAGE_CACHE_SHIFT;
+		index = wbc->range_start >> PAGE_SHIFT;
+		end = wbc->range_end >> PAGE_SHIFT;
 		if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
 			range_whole = 1;
 		cycled = 1; /* ignore range_cyclic tests */
@@ -1448,11 +1448,11 @@ static int prepare_write_begin(struct f2fs_sb_info *sbi,
 	 * the block addresses when there is no need to fill the page.
 	 */
 	if (!f2fs_has_inline_data(inode) && !f2fs_encrypted_inode(inode) &&
-					len == PAGE_CACHE_SIZE)
+					len == PAGE_SIZE)
 		return 0;
 
 	if (f2fs_has_inline_data(inode) ||
-			(pos & PAGE_CACHE_MASK) >= i_size_read(inode)) {
+			(pos & PAGE_MASK) >= i_size_read(inode)) {
 		f2fs_lock_op(sbi);
 		locked = true;
 	}
@@ -1513,7 +1513,7 @@ static int f2fs_write_begin(struct file *file, struct address_space *mapping,
 	struct inode *inode = mapping->host;
 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 	struct page *page = NULL;
-	pgoff_t index = ((unsigned long long) pos) >> PAGE_CACHE_SHIFT;
+	pgoff_t index = ((unsigned long long) pos) >> PAGE_SHIFT;
 	bool need_balance = false;
 	block_t blkaddr = NULL_ADDR;
 	int err = 0;
@@ -1561,22 +1561,22 @@ repeat:
 	if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode))
 		f2fs_wait_on_encrypted_page_writeback(sbi, blkaddr);
 
-	if (len == PAGE_CACHE_SIZE)
+	if (len == PAGE_SIZE)
 		goto out_update;
 	if (PageUptodate(page))
 		goto out_clear;
 
-	if ((pos & PAGE_CACHE_MASK) >= i_size_read(inode)) {
-		unsigned start = pos & (PAGE_CACHE_SIZE - 1);
+	if ((pos & PAGE_MASK) >= i_size_read(inode)) {
+		unsigned start = pos & (PAGE_SIZE - 1);
 		unsigned end = start + len;
 
 		/* Reading beyond i_size is simple: memset to zero */
-		zero_user_segments(page, 0, start, end, PAGE_CACHE_SIZE);
+		zero_user_segments(page, 0, start, end, PAGE_SIZE);
 		goto out_update;
 	}
 
 	if (blkaddr == NEW_ADDR) {
-		zero_user_segment(page, 0, PAGE_CACHE_SIZE);
+		zero_user_segment(page, 0, PAGE_SIZE);
 	} else {
 		struct f2fs_io_info fio = {
 			.sbi = sbi,
@@ -1688,7 +1688,7 @@ void f2fs_invalidate_page(struct page *page, unsigned int offset,
 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 
 	if (inode->i_ino >= F2FS_ROOT_INO(sbi) &&
-		(offset % PAGE_CACHE_SIZE || length != PAGE_CACHE_SIZE))
+		(offset % PAGE_SIZE || length != PAGE_SIZE))
 		return;
 
 	if (PageDirty(page)) {