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, 28 insertions, 28 deletions

diff --git a/fs/ntfs/compress.c b/fs/ntfs/compress.c
index f82498c35e78..b6074a56661b 100644
--- a/fs/ntfs/compress.c
+++ b/fs/ntfs/compress.c
@@ -104,7 +104,7 @@ static void zero_partial_compressed_page(struct page *page,
 	unsigned int kp_ofs;
 
 	ntfs_debug("Zeroing page region outside initialized size.");
-	if (((s64)page->index << PAGE_CACHE_SHIFT) >= initialized_size) {
+	if (((s64)page->index << PAGE_SHIFT) >= initialized_size) {
 		/*
 		 * FIXME: Using clear_page() will become wrong when we get
 		 * PAGE_CACHE_SIZE != PAGE_SIZE but for now there is no problem.
@@ -112,8 +112,8 @@ static void zero_partial_compressed_page(struct page *page,
 		clear_page(kp);
 		return;
 	}
-	kp_ofs = initialized_size & ~PAGE_CACHE_MASK;
-	memset(kp + kp_ofs, 0, PAGE_CACHE_SIZE - kp_ofs);
+	kp_ofs = initialized_size & ~PAGE_MASK;
+	memset(kp + kp_ofs, 0, PAGE_SIZE - kp_ofs);
 	return;
 }
 
@@ -123,7 +123,7 @@ static void zero_partial_compressed_page(struct page *page,
 static inline void handle_bounds_compressed_page(struct page *page,
 		const loff_t i_size, const s64 initialized_size)
 {
-	if ((page->index >= (initialized_size >> PAGE_CACHE_SHIFT)) &&
+	if ((page->index >= (initialized_size >> PAGE_SHIFT)) &&
 			(initialized_size < i_size))
 		zero_partial_compressed_page(page, initialized_size);
 	return;
@@ -241,7 +241,7 @@ return_error:
 				if (di == xpage)
 					*xpage_done = 1;
 				else
-					page_cache_release(dp);
+					put_page(dp);
 				dest_pages[di] = NULL;
 			}
 		}
@@ -274,7 +274,7 @@ return_error:
 		cb = cb_sb_end;
 
 		/* Advance destination position to next sub-block. */
-		*dest_ofs = (*dest_ofs + NTFS_SB_SIZE) & ~PAGE_CACHE_MASK;
+		*dest_ofs = (*dest_ofs + NTFS_SB_SIZE) & ~PAGE_MASK;
 		if (!*dest_ofs && (++*dest_index > dest_max_index))
 			goto return_overflow;
 		goto do_next_sb;
@@ -301,7 +301,7 @@ return_error:
 
 		/* Advance destination position to next sub-block. */
 		*dest_ofs += NTFS_SB_SIZE;
-		if (!(*dest_ofs &= ~PAGE_CACHE_MASK)) {
+		if (!(*dest_ofs &= ~PAGE_MASK)) {
 finalize_page:
 			/*
 			 * First stage: add current page index to array of
@@ -335,7 +335,7 @@ do_next_tag:
 			*dest_ofs += nr_bytes;
 		}
 		/* We have finished the current sub-block. */
-		if (!(*dest_ofs &= ~PAGE_CACHE_MASK))
+		if (!(*dest_ofs &= ~PAGE_MASK))
 			goto finalize_page;
 		goto do_next_sb;
 	}
@@ -498,13 +498,13 @@ int ntfs_read_compressed_block(struct page *page)
 	VCN vcn;
 	LCN lcn;
 	/* The first wanted vcn (minimum alignment is PAGE_CACHE_SIZE). */
-	VCN start_vcn = (((s64)index << PAGE_CACHE_SHIFT) & ~cb_size_mask) >>
+	VCN start_vcn = (((s64)index << PAGE_SHIFT) & ~cb_size_mask) >>
 			vol->cluster_size_bits;
 	/*
 	 * The first vcn after the last wanted vcn (minimum alignment is again
 	 * PAGE_CACHE_SIZE.
 	 */
-	VCN end_vcn = ((((s64)(index + 1UL) << PAGE_CACHE_SHIFT) + cb_size - 1)
+	VCN end_vcn = ((((s64)(index + 1UL) << PAGE_SHIFT) + cb_size - 1)
 			& ~cb_size_mask) >> vol->cluster_size_bits;
 	/* Number of compression blocks (cbs) in the wanted vcn range. */
 	unsigned int nr_cbs = (end_vcn - start_vcn) << vol->cluster_size_bits
@@ -515,7 +515,7 @@ int ntfs_read_compressed_block(struct page *page)
 	 * guarantees of start_vcn and end_vcn, no need to round up here.
 	 */
 	unsigned int nr_pages = (end_vcn - start_vcn) <<
-			vol->cluster_size_bits >> PAGE_CACHE_SHIFT;
+			vol->cluster_size_bits >> PAGE_SHIFT;
 	unsigned int xpage, max_page, cur_page, cur_ofs, i;
 	unsigned int cb_clusters, cb_max_ofs;
 	int block, max_block, cb_max_page, bhs_size, nr_bhs, err = 0;
@@ -549,7 +549,7 @@ int ntfs_read_compressed_block(struct page *page)
 	 * We have already been given one page, this is the one we must do.
 	 * Once again, the alignment guarantees keep it simple.
 	 */
-	offset = start_vcn << vol->cluster_size_bits >> PAGE_CACHE_SHIFT;
+	offset = start_vcn << vol->cluster_size_bits >> PAGE_SHIFT;
 	xpage = index - offset;
 	pages[xpage] = page;
 	/*
@@ -560,13 +560,13 @@ int ntfs_read_compressed_block(struct page *page)
 	i_size = i_size_read(VFS_I(ni));
 	initialized_size = ni->initialized_size;
 	read_unlock_irqrestore(&ni->size_lock, flags);
-	max_page = ((i_size + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT) -
+	max_page = ((i_size + PAGE_SIZE - 1) >> PAGE_SHIFT) -
 			offset;
 	/* Is the page fully outside i_size? (truncate in progress) */
 	if (xpage >= max_page) {
 		kfree(bhs);
 		kfree(pages);
-		zero_user(page, 0, PAGE_CACHE_SIZE);
+		zero_user(page, 0, PAGE_SIZE);
 		ntfs_debug("Compressed read outside i_size - truncated?");
 		SetPageUptodate(page);
 		unlock_page(page);
@@ -591,7 +591,7 @@ int ntfs_read_compressed_block(struct page *page)
 				continue;
 			}
 			unlock_page(page);
-			page_cache_release(page);
+			put_page(page);
 			pages[i] = NULL;
 		}
 	}
@@ -735,9 +735,9 @@ lock_retry_remap:
 	ntfs_debug("Successfully read the compression block.");
 
 	/* The last page and maximum offset within it for the current cb. */
-	cb_max_page = (cur_page << PAGE_CACHE_SHIFT) + cur_ofs + cb_size;
-	cb_max_ofs = cb_max_page & ~PAGE_CACHE_MASK;
-	cb_max_page >>= PAGE_CACHE_SHIFT;
+	cb_max_page = (cur_page << PAGE_SHIFT) + cur_ofs + cb_size;
+	cb_max_ofs = cb_max_page & ~PAGE_MASK;
+	cb_max_page >>= PAGE_SHIFT;
 
 	/* Catch end of file inside a compression block. */
 	if (cb_max_page > max_page)
@@ -762,7 +762,7 @@ lock_retry_remap:
 					clear_page(page_address(page));
 				else
 					memset(page_address(page) + cur_ofs, 0,
-							PAGE_CACHE_SIZE -
+							PAGE_SIZE -
 							cur_ofs);
 				flush_dcache_page(page);
 				kunmap(page);
@@ -771,10 +771,10 @@ lock_retry_remap:
 				if (cur_page == xpage)
 					xpage_done = 1;
 				else
-					page_cache_release(page);
+					put_page(page);
 				pages[cur_page] = NULL;
 			}
-			cb_pos += PAGE_CACHE_SIZE - cur_ofs;
+			cb_pos += PAGE_SIZE - cur_ofs;
 			cur_ofs = 0;
 			if (cb_pos >= cb_end)
 				break;
@@ -816,8 +816,8 @@ lock_retry_remap:
 			page = pages[cur_page];
 			if (page)
 				memcpy(page_address(page) + cur_ofs, cb_pos,
-						PAGE_CACHE_SIZE - cur_ofs);
-			cb_pos += PAGE_CACHE_SIZE - cur_ofs;
+						PAGE_SIZE - cur_ofs);
+			cb_pos += PAGE_SIZE - cur_ofs;
 			cur_ofs = 0;
 			if (cb_pos >= cb_end)
 				break;
@@ -850,10 +850,10 @@ lock_retry_remap:
 				if (cur2_page == xpage)
 					xpage_done = 1;
 				else
-					page_cache_release(page);
+					put_page(page);
 				pages[cur2_page] = NULL;
 			}
-			cb_pos2 += PAGE_CACHE_SIZE - cur_ofs2;
+			cb_pos2 += PAGE_SIZE - cur_ofs2;
 			cur_ofs2 = 0;
 			if (cb_pos2 >= cb_end)
 				break;
@@ -884,7 +884,7 @@ lock_retry_remap:
 					kunmap(page);
 					unlock_page(page);
 					if (prev_cur_page != xpage)
-						page_cache_release(page);
+						put_page(page);
 					pages[prev_cur_page] = NULL;
 				}
 			}
@@ -914,7 +914,7 @@ lock_retry_remap:
 			kunmap(page);
 			unlock_page(page);
 			if (cur_page != xpage)
-				page_cache_release(page);
+				put_page(page);
 			pages[cur_page] = NULL;
 		}
 	}
@@ -961,7 +961,7 @@ err_out:
 			kunmap(page);
 			unlock_page(page);
 			if (i != xpage)
-				page_cache_release(page);
+				put_page(page);
 		}
 	}
 	kfree(pages);