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, 47 insertions, 47 deletions

diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index ff882aeaccc6..5ce540dc6996 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -1833,7 +1833,7 @@ refind_writable:
 static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
 {
 	struct address_space *mapping = page->mapping;
-	loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
+	loff_t offset = (loff_t)page->index << PAGE_SHIFT;
 	char *write_data;
 	int rc = -EFAULT;
 	int bytes_written = 0;
@@ -1849,7 +1849,7 @@ static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
 	write_data = kmap(page);
 	write_data += from;
 
-	if ((to > PAGE_CACHE_SIZE) || (from > to)) {
+	if ((to > PAGE_SIZE) || (from > to)) {
 		kunmap(page);
 		return -EIO;
 	}
@@ -1991,7 +1991,7 @@ wdata_prepare_pages(struct cifs_writedata *wdata, unsigned int found_pages,
 
 	/* put any pages we aren't going to use */
 	for (i = nr_pages; i < found_pages; i++) {
-		page_cache_release(wdata->pages[i]);
+		put_page(wdata->pages[i]);
 		wdata->pages[i] = NULL;
 	}
 
@@ -2009,11 +2009,11 @@ wdata_send_pages(struct cifs_writedata *wdata, unsigned int nr_pages,
 	wdata->sync_mode = wbc->sync_mode;
 	wdata->nr_pages = nr_pages;
 	wdata->offset = page_offset(wdata->pages[0]);
-	wdata->pagesz = PAGE_CACHE_SIZE;
+	wdata->pagesz = PAGE_SIZE;
 	wdata->tailsz = min(i_size_read(mapping->host) -
 			page_offset(wdata->pages[nr_pages - 1]),
-			(loff_t)PAGE_CACHE_SIZE);
-	wdata->bytes = ((nr_pages - 1) * PAGE_CACHE_SIZE) + wdata->tailsz;
+			(loff_t)PAGE_SIZE);
+	wdata->bytes = ((nr_pages - 1) * PAGE_SIZE) + wdata->tailsz;
 
 	if (wdata->cfile != NULL)
 		cifsFileInfo_put(wdata->cfile);
@@ -2047,15 +2047,15 @@ static int cifs_writepages(struct address_space *mapping,
 	 * If wsize is smaller than the page cache size, default to writing
 	 * one page at a time via cifs_writepage
 	 */
-	if (cifs_sb->wsize < PAGE_CACHE_SIZE)
+	if (cifs_sb->wsize < PAGE_SIZE)
 		return generic_writepages(mapping, wbc);
 
 	if (wbc->range_cyclic) {
 		index = mapping->writeback_index; /* Start from prev offset */
 		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 = true;
 		scanned = true;
@@ -2071,7 +2071,7 @@ retry:
 		if (rc)
 			break;
 
-		tofind = min((wsize / PAGE_CACHE_SIZE) - 1, end - index) + 1;
+		tofind = min((wsize / PAGE_SIZE) - 1, end - index) + 1;
 
 		wdata = wdata_alloc_and_fillpages(tofind, mapping, end, &index,
 						  &found_pages);
@@ -2111,7 +2111,7 @@ retry:
 				else
 					SetPageError(wdata->pages[i]);
 				end_page_writeback(wdata->pages[i]);
-				page_cache_release(wdata->pages[i]);
+				put_page(wdata->pages[i]);
 			}
 			if (rc != -EAGAIN)
 				mapping_set_error(mapping, rc);
@@ -2154,7 +2154,7 @@ cifs_writepage_locked(struct page *page, struct writeback_control *wbc)
 
 	xid = get_xid();
 /* BB add check for wbc flags */
-	page_cache_get(page);
+	get_page(page);
 	if (!PageUptodate(page))
 		cifs_dbg(FYI, "ppw - page not up to date\n");
 
@@ -2170,7 +2170,7 @@ cifs_writepage_locked(struct page *page, struct writeback_control *wbc)
 	 */
 	set_page_writeback(page);
 retry_write:
-	rc = cifs_partialpagewrite(page, 0, PAGE_CACHE_SIZE);
+	rc = cifs_partialpagewrite(page, 0, PAGE_SIZE);
 	if (rc == -EAGAIN && wbc->sync_mode == WB_SYNC_ALL)
 		goto retry_write;
 	else if (rc == -EAGAIN)
@@ -2180,7 +2180,7 @@ retry_write:
 	else
 		SetPageUptodate(page);
 	end_page_writeback(page);
-	page_cache_release(page);
+	put_page(page);
 	free_xid(xid);
 	return rc;
 }
@@ -2214,12 +2214,12 @@ static int cifs_write_end(struct file *file, struct address_space *mapping,
 		if (copied == len)
 			SetPageUptodate(page);
 		ClearPageChecked(page);
-	} else if (!PageUptodate(page) && copied == PAGE_CACHE_SIZE)
+	} else if (!PageUptodate(page) && copied == PAGE_SIZE)
 		SetPageUptodate(page);
 
 	if (!PageUptodate(page)) {
 		char *page_data;
-		unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
+		unsigned offset = pos & (PAGE_SIZE - 1);
 		unsigned int xid;
 
 		xid = get_xid();
@@ -2248,7 +2248,7 @@ static int cifs_write_end(struct file *file, struct address_space *mapping,
 	}
 
 	unlock_page(page);
-	page_cache_release(page);
+	put_page(page);
 
 	return rc;
 }
@@ -3286,9 +3286,9 @@ cifs_readv_complete(struct work_struct *work)
 		    (rdata->result == -EAGAIN && got_bytes))
 			cifs_readpage_to_fscache(rdata->mapping->host, page);
 
-		got_bytes -= min_t(unsigned int, PAGE_CACHE_SIZE, got_bytes);
+		got_bytes -= min_t(unsigned int, PAGE_SIZE, got_bytes);
 
-		page_cache_release(page);
+		put_page(page);
 		rdata->pages[i] = NULL;
 	}
 	kref_put(&rdata->refcount, cifs_readdata_release);
@@ -3307,21 +3307,21 @@ cifs_readpages_read_into_pages(struct TCP_Server_Info *server,
 
 	/* determine the eof that the server (probably) has */
 	eof = CIFS_I(rdata->mapping->host)->server_eof;
-	eof_index = eof ? (eof - 1) >> PAGE_CACHE_SHIFT : 0;
+	eof_index = eof ? (eof - 1) >> PAGE_SHIFT : 0;
 	cifs_dbg(FYI, "eof=%llu eof_index=%lu\n", eof, eof_index);
 
 	rdata->got_bytes = 0;
-	rdata->tailsz = PAGE_CACHE_SIZE;
+	rdata->tailsz = PAGE_SIZE;
 	for (i = 0; i < nr_pages; i++) {
 		struct page *page = rdata->pages[i];
 
-		if (len >= PAGE_CACHE_SIZE) {
+		if (len >= PAGE_SIZE) {
 			/* enough data to fill the page */
 			iov.iov_base = kmap(page);
-			iov.iov_len = PAGE_CACHE_SIZE;
+			iov.iov_len = PAGE_SIZE;
 			cifs_dbg(FYI, "%u: idx=%lu iov_base=%p iov_len=%zu\n",
 				 i, page->index, iov.iov_base, iov.iov_len);
-			len -= PAGE_CACHE_SIZE;
+			len -= PAGE_SIZE;
 		} else if (len > 0) {
 			/* enough for partial page, fill and zero the rest */
 			iov.iov_base = kmap(page);
@@ -3329,7 +3329,7 @@ cifs_readpages_read_into_pages(struct TCP_Server_Info *server,
 			cifs_dbg(FYI, "%u: idx=%lu iov_base=%p iov_len=%zu\n",
 				 i, page->index, iov.iov_base, iov.iov_len);
 			memset(iov.iov_base + len,
-				'\0', PAGE_CACHE_SIZE - len);
+				'\0', PAGE_SIZE - len);
 			rdata->tailsz = len;
 			len = 0;
 		} else if (page->index > eof_index) {
@@ -3341,12 +3341,12 @@ cifs_readpages_read_into_pages(struct TCP_Server_Info *server,
 			 * to prevent the VFS from repeatedly attempting to
 			 * fill them until the writes are flushed.
 			 */
-			zero_user(page, 0, PAGE_CACHE_SIZE);
+			zero_user(page, 0, PAGE_SIZE);
 			lru_cache_add_file(page);
 			flush_dcache_page(page);
 			SetPageUptodate(page);
 			unlock_page(page);
-			page_cache_release(page);
+			put_page(page);
 			rdata->pages[i] = NULL;
 			rdata->nr_pages--;
 			continue;
@@ -3354,7 +3354,7 @@ cifs_readpages_read_into_pages(struct TCP_Server_Info *server,
 			/* no need to hold page hostage */
 			lru_cache_add_file(page);
 			unlock_page(page);
-			page_cache_release(page);
+			put_page(page);
 			rdata->pages[i] = NULL;
 			rdata->nr_pages--;
 			continue;
@@ -3402,8 +3402,8 @@ readpages_get_pages(struct address_space *mapping, struct list_head *page_list,
 	}
 
 	/* move first page to the tmplist */
-	*offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
-	*bytes = PAGE_CACHE_SIZE;
+	*offset = (loff_t)page->index << PAGE_SHIFT;
+	*bytes = PAGE_SIZE;
 	*nr_pages = 1;
 	list_move_tail(&page->lru, tmplist);
 
@@ -3415,7 +3415,7 @@ readpages_get_pages(struct address_space *mapping, struct list_head *page_list,
 			break;
 
 		/* would this page push the read over the rsize? */
-		if (*bytes + PAGE_CACHE_SIZE > rsize)
+		if (*bytes + PAGE_SIZE > rsize)
 			break;
 
 		__SetPageLocked(page);
@@ -3424,7 +3424,7 @@ readpages_get_pages(struct address_space *mapping, struct list_head *page_list,
 			break;
 		}
 		list_move_tail(&page->lru, tmplist);
-		(*bytes) += PAGE_CACHE_SIZE;
+		(*bytes) += PAGE_SIZE;
 		expected_index++;
 		(*nr_pages)++;
 	}
@@ -3493,7 +3493,7 @@ static int cifs_readpages(struct file *file, struct address_space *mapping,
 		 * reach this point however since we set ra_pages to 0 when the
 		 * rsize is smaller than a cache page.
 		 */
-		if (unlikely(rsize < PAGE_CACHE_SIZE)) {
+		if (unlikely(rsize < PAGE_SIZE)) {
 			add_credits_and_wake_if(server, credits, 0);
 			return 0;
 		}
@@ -3512,7 +3512,7 @@ static int cifs_readpages(struct file *file, struct address_space *mapping,
 				list_del(&page->lru);
 				lru_cache_add_file(page);
 				unlock_page(page);
-				page_cache_release(page);
+				put_page(page);
 			}
 			rc = -ENOMEM;
 			add_credits_and_wake_if(server, credits, 0);
@@ -3524,7 +3524,7 @@ static int cifs_readpages(struct file *file, struct address_space *mapping,
 		rdata->offset = offset;
 		rdata->bytes = bytes;
 		rdata->pid = pid;
-		rdata->pagesz = PAGE_CACHE_SIZE;
+		rdata->pagesz = PAGE_SIZE;
 		rdata->read_into_pages = cifs_readpages_read_into_pages;
 		rdata->credits = credits;
 
@@ -3542,7 +3542,7 @@ static int cifs_readpages(struct file *file, struct address_space *mapping,
 				page = rdata->pages[i];
 				lru_cache_add_file(page);
 				unlock_page(page);
-				page_cache_release(page);
+				put_page(page);
 			}
 			/* Fallback to the readpage in error/reconnect cases */
 			kref_put(&rdata->refcount, cifs_readdata_release);
@@ -3577,7 +3577,7 @@ static int cifs_readpage_worker(struct file *file, struct page *page,
 	read_data = kmap(page);
 	/* for reads over a certain size could initiate async read ahead */
 
-	rc = cifs_read(file, read_data, PAGE_CACHE_SIZE, poffset);
+	rc = cifs_read(file, read_data, PAGE_SIZE, poffset);
 
 	if (rc < 0)
 		goto io_error;
@@ -3587,8 +3587,8 @@ static int cifs_readpage_worker(struct file *file, struct page *page,
 	file_inode(file)->i_atime =
 		current_fs_time(file_inode(file)->i_sb);
 
-	if (PAGE_CACHE_SIZE > rc)
-		memset(read_data + rc, 0, PAGE_CACHE_SIZE - rc);
+	if (PAGE_SIZE > rc)
+		memset(read_data + rc, 0, PAGE_SIZE - rc);
 
 	flush_dcache_page(page);
 	SetPageUptodate(page);
@@ -3608,7 +3608,7 @@ read_complete:
 
 static int cifs_readpage(struct file *file, struct page *page)
 {
-	loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
+	loff_t offset = (loff_t)page->index << PAGE_SHIFT;
 	int rc = -EACCES;
 	unsigned int xid;
 
@@ -3679,8 +3679,8 @@ static int cifs_write_begin(struct file *file, struct address_space *mapping,
 			struct page **pagep, void **fsdata)
 {
 	int oncethru = 0;
-	pgoff_t index = pos >> PAGE_CACHE_SHIFT;
-	loff_t offset = pos & (PAGE_CACHE_SIZE - 1);
+	pgoff_t index = pos >> PAGE_SHIFT;
+	loff_t offset = pos & (PAGE_SIZE - 1);
 	loff_t page_start = pos & PAGE_MASK;
 	loff_t i_size;
 	struct page *page;
@@ -3703,7 +3703,7 @@ start:
 	 * the server. If the write is short, we'll end up doing a sync write
 	 * instead.
 	 */
-	if (len == PAGE_CACHE_SIZE)
+	if (len == PAGE_SIZE)
 		goto out;
 
 	/*
@@ -3718,7 +3718,7 @@ start:
 		    (offset == 0 && (pos + len) >= i_size)) {
 			zero_user_segments(page, 0, offset,
 					   offset + len,
-					   PAGE_CACHE_SIZE);
+					   PAGE_SIZE);
 			/*
 			 * PageChecked means that the parts of the page
 			 * to which we're not writing are considered up
@@ -3737,7 +3737,7 @@ start:
 		 * do a sync write instead since PG_uptodate isn't set.
 		 */
 		cifs_readpage_worker(file, page, &page_start);
-		page_cache_release(page);
+		put_page(page);
 		oncethru = 1;
 		goto start;
 	} else {
@@ -3764,7 +3764,7 @@ static void cifs_invalidate_page(struct page *page, unsigned int offset,
 {
 	struct cifsInodeInfo *cifsi = CIFS_I(page->mapping->host);
 
-	if (offset == 0 && length == PAGE_CACHE_SIZE)
+	if (offset == 0 && length == PAGE_SIZE)
 		cifs_fscache_invalidate_page(page, &cifsi->vfs_inode);
 }
 
@@ -3772,7 +3772,7 @@ static int cifs_launder_page(struct page *page)
 {
 	int rc = 0;
 	loff_t range_start = page_offset(page);
-	loff_t range_end = range_start + (loff_t)(PAGE_CACHE_SIZE - 1);
+	loff_t range_end = range_start + (loff_t)(PAGE_SIZE - 1);
 	struct writeback_control wbc = {
 		.sync_mode = WB_SYNC_ALL,
 		.nr_to_write = 0,