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, 27 insertions, 27 deletions

diff --git a/fs/ntfs/file.c b/fs/ntfs/file.c
index bed4d427dfae..2dae60857544 100644
--- a/fs/ntfs/file.c
+++ b/fs/ntfs/file.c
@@ -220,8 +220,8 @@ do_non_resident_extend:
 		m = NULL;
 	}
 	mapping = vi->i_mapping;
-	index = old_init_size >> PAGE_CACHE_SHIFT;
-	end_index = (new_init_size + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+	index = old_init_size >> PAGE_SHIFT;
+	end_index = (new_init_size + PAGE_SIZE - 1) >> PAGE_SHIFT;
 	do {
 		/*
 		 * Read the page.  If the page is not present, this will zero
@@ -233,7 +233,7 @@ do_non_resident_extend:
 			goto init_err_out;
 		}
 		if (unlikely(PageError(page))) {
-			page_cache_release(page);
+			put_page(page);
 			err = -EIO;
 			goto init_err_out;
 		}
@@ -242,13 +242,13 @@ do_non_resident_extend:
 		 * enough to make ntfs_writepage() work.
 		 */
 		write_lock_irqsave(&ni->size_lock, flags);
-		ni->initialized_size = (s64)(index + 1) << PAGE_CACHE_SHIFT;
+		ni->initialized_size = (s64)(index + 1) << PAGE_SHIFT;
 		if (ni->initialized_size > new_init_size)
 			ni->initialized_size = new_init_size;
 		write_unlock_irqrestore(&ni->size_lock, flags);
 		/* Set the page dirty so it gets written out. */
 		set_page_dirty(page);
-		page_cache_release(page);
+		put_page(page);
 		/*
 		 * Play nice with the vm and the rest of the system.  This is
 		 * very much needed as we can potentially be modifying the
@@ -543,7 +543,7 @@ out:
 err_out:
 	while (nr > 0) {
 		unlock_page(pages[--nr]);
-		page_cache_release(pages[nr]);
+		put_page(pages[nr]);
 	}
 	goto out;
 }
@@ -653,7 +653,7 @@ static int ntfs_prepare_pages_for_non_resident_write(struct page **pages,
 	u = 0;
 do_next_page:
 	page = pages[u];
-	bh_pos = (s64)page->index << PAGE_CACHE_SHIFT;
+	bh_pos = (s64)page->index << PAGE_SHIFT;
 	bh = head = page_buffers(page);
 	do {
 		VCN cdelta;
@@ -810,11 +810,11 @@ map_buffer_cached:
 					
 				kaddr = kmap_atomic(page);
 				if (bh_pos < pos) {
-					pofs = bh_pos & ~PAGE_CACHE_MASK;
+					pofs = bh_pos & ~PAGE_MASK;
 					memset(kaddr + pofs, 0, pos - bh_pos);
 				}
 				if (bh_end > end) {
-					pofs = end & ~PAGE_CACHE_MASK;
+					pofs = end & ~PAGE_MASK;
 					memset(kaddr + pofs, 0, bh_end - end);
 				}
 				kunmap_atomic(kaddr);
@@ -942,7 +942,7 @@ rl_not_mapped_enoent:
 		 * unmapped.  This can only happen when the cluster size is
 		 * less than the page cache size.
 		 */
-		if (unlikely(vol->cluster_size < PAGE_CACHE_SIZE)) {
+		if (unlikely(vol->cluster_size < PAGE_SIZE)) {
 			bh_cend = (bh_end + vol->cluster_size - 1) >>
 					vol->cluster_size_bits;
 			if ((bh_cend <= cpos || bh_cpos >= cend)) {
@@ -1208,7 +1208,7 @@ rl_not_mapped_enoent:
 		wait_on_buffer(bh);
 		if (likely(buffer_uptodate(bh))) {
 			page = bh->b_page;
-			bh_pos = ((s64)page->index << PAGE_CACHE_SHIFT) +
+			bh_pos = ((s64)page->index << PAGE_SHIFT) +
 					bh_offset(bh);
 			/*
 			 * If the buffer overflows the initialized size, need
@@ -1350,7 +1350,7 @@ rl_not_mapped_enoent:
 		bh = head = page_buffers(page);
 		do {
 			if (u == nr_pages &&
-					((s64)page->index << PAGE_CACHE_SHIFT) +
+					((s64)page->index << PAGE_SHIFT) +
 					bh_offset(bh) >= end)
 				break;
 			if (!buffer_new(bh))
@@ -1422,7 +1422,7 @@ static inline int ntfs_commit_pages_after_non_resident_write(
 		bool partial;
 
 		page = pages[u];
-		bh_pos = (s64)page->index << PAGE_CACHE_SHIFT;
+		bh_pos = (s64)page->index << PAGE_SHIFT;
 		bh = head = page_buffers(page);
 		partial = false;
 		do {
@@ -1639,7 +1639,7 @@ static int ntfs_commit_pages_after_write(struct page **pages,
 		if (end < attr_len)
 			memcpy(kaddr + end, kattr + end, attr_len - end);
 		/* Zero the region outside the end of the attribute value. */
-		memset(kaddr + attr_len, 0, PAGE_CACHE_SIZE - attr_len);
+		memset(kaddr + attr_len, 0, PAGE_SIZE - attr_len);
 		flush_dcache_page(page);
 		SetPageUptodate(page);
 	}
@@ -1706,7 +1706,7 @@ static size_t ntfs_copy_from_user_iter(struct page **pages, unsigned nr_pages,
 	unsigned len, copied;
 
 	do {
-		len = PAGE_CACHE_SIZE - ofs;
+		len = PAGE_SIZE - ofs;
 		if (len > bytes)
 			len = bytes;
 		copied = iov_iter_copy_from_user_atomic(*pages, &data, ofs,
@@ -1724,14 +1724,14 @@ out:
 	return total;
 err:
 	/* Zero the rest of the target like __copy_from_user(). */
-	len = PAGE_CACHE_SIZE - copied;
+	len = PAGE_SIZE - copied;
 	do {
 		if (len > bytes)
 			len = bytes;
 		zero_user(*pages, copied, len);
 		bytes -= len;
 		copied = 0;
-		len = PAGE_CACHE_SIZE;
+		len = PAGE_SIZE;
 	} while (++pages < last_page);
 	goto out;
 }
@@ -1787,8 +1787,8 @@ static ssize_t ntfs_perform_write(struct file *file, struct iov_iter *i,
 	 * attributes.
 	 */
 	nr_pages = 1;
-	if (vol->cluster_size > PAGE_CACHE_SIZE && NInoNonResident(ni))
-		nr_pages = vol->cluster_size >> PAGE_CACHE_SHIFT;
+	if (vol->cluster_size > PAGE_SIZE && NInoNonResident(ni))
+		nr_pages = vol->cluster_size >> PAGE_SHIFT;
 	last_vcn = -1;
 	do {
 		VCN vcn;
@@ -1796,9 +1796,9 @@ static ssize_t ntfs_perform_write(struct file *file, struct iov_iter *i,
 		unsigned ofs, do_pages, u;
 		size_t copied;
 
-		start_idx = idx = pos >> PAGE_CACHE_SHIFT;
-		ofs = pos & ~PAGE_CACHE_MASK;
-		bytes = PAGE_CACHE_SIZE - ofs;
+		start_idx = idx = pos >> PAGE_SHIFT;
+		ofs = pos & ~PAGE_MASK;
+		bytes = PAGE_SIZE - ofs;
 		do_pages = 1;
 		if (nr_pages > 1) {
 			vcn = pos >> vol->cluster_size_bits;
@@ -1832,7 +1832,7 @@ static ssize_t ntfs_perform_write(struct file *file, struct iov_iter *i,
 				if (lcn == LCN_HOLE) {
 					start_idx = (pos & ~(s64)
 							vol->cluster_size_mask)
-							>> PAGE_CACHE_SHIFT;
+							>> PAGE_SHIFT;
 					bytes = vol->cluster_size - (pos &
 							vol->cluster_size_mask);
 					do_pages = nr_pages;
@@ -1871,12 +1871,12 @@ again:
 			if (unlikely(status)) {
 				do {
 					unlock_page(pages[--do_pages]);
-					page_cache_release(pages[do_pages]);
+					put_page(pages[do_pages]);
 				} while (do_pages);
 				break;
 			}
 		}
-		u = (pos >> PAGE_CACHE_SHIFT) - pages[0]->index;
+		u = (pos >> PAGE_SHIFT) - pages[0]->index;
 		copied = ntfs_copy_from_user_iter(pages + u, do_pages - u, ofs,
 					i, bytes);
 		ntfs_flush_dcache_pages(pages + u, do_pages - u);
@@ -1889,7 +1889,7 @@ again:
 		}
 		do {
 			unlock_page(pages[--do_pages]);
-			page_cache_release(pages[do_pages]);
+			put_page(pages[do_pages]);
 		} while (do_pages);
 		if (unlikely(status < 0))
 			break;
@@ -1921,7 +1921,7 @@ again:
 		}
 	} while (iov_iter_count(i));
 	if (cached_page)
-		page_cache_release(cached_page);
+		put_page(cached_page);
 	ntfs_debug("Done.  Returning %s (written 0x%lx, status %li).",
 			written ? "written" : "status", (unsigned long)written,
 			(long)status);