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>

8 files changed, 14 insertions, 14 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
index ab34190859a8..c018b021707c 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
@@ -616,7 +616,7 @@ static void amdgpu_ttm_tt_unpin_userptr(struct ttm_tt *ttm)
 			set_page_dirty(page);
 
 		mark_page_accessed(page);
-		page_cache_release(page);
+		put_page(page);
 	}
 
 	sg_free_table(ttm->sg);
diff --git a/drivers/gpu/drm/armada/armada_gem.c b/drivers/gpu/drm/armada/armada_gem.c
index 6e731db31aa4..aca7f9cc6109 100644
--- a/drivers/gpu/drm/armada/armada_gem.c
+++ b/drivers/gpu/drm/armada/armada_gem.c
@@ -481,7 +481,7 @@ armada_gem_prime_map_dma_buf(struct dma_buf_attachment *attach,
 
  release:
 	for_each_sg(sgt->sgl, sg, num, i)
-		page_cache_release(sg_page(sg));
+		put_page(sg_page(sg));
  free_table:
 	sg_free_table(sgt);
  free_sgt:
@@ -502,7 +502,7 @@ static void armada_gem_prime_unmap_dma_buf(struct dma_buf_attachment *attach,
 	if (dobj->obj.filp) {
 		struct scatterlist *sg;
 		for_each_sg(sgt->sgl, sg, sgt->nents, i)
-			page_cache_release(sg_page(sg));
+			put_page(sg_page(sg));
 	}
 
 	sg_free_table(sgt);
diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
index 2e8c77e71e1f..da0c5320789f 100644
--- a/drivers/gpu/drm/drm_gem.c
+++ b/drivers/gpu/drm/drm_gem.c
@@ -534,7 +534,7 @@ struct page **drm_gem_get_pages(struct drm_gem_object *obj)
 
 fail:
 	while (i--)
-		page_cache_release(pages[i]);
+		put_page(pages[i]);
 
 	drm_free_large(pages);
 	return ERR_CAST(p);
@@ -569,7 +569,7 @@ void drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages,
 			mark_page_accessed(pages[i]);
 
 		/* Undo the reference we took when populating the table */
-		page_cache_release(pages[i]);
+		put_page(pages[i]);
 	}
 
 	drm_free_large(pages);
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 3d31d3ac589e..dabc08987b5e 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -177,7 +177,7 @@ i915_gem_object_get_pages_phys(struct drm_i915_gem_object *obj)
 		drm_clflush_virt_range(vaddr, PAGE_SIZE);
 		kunmap_atomic(src);
 
-		page_cache_release(page);
+		put_page(page);
 		vaddr += PAGE_SIZE;
 	}
 
@@ -243,7 +243,7 @@ i915_gem_object_put_pages_phys(struct drm_i915_gem_object *obj)
 			set_page_dirty(page);
 			if (obj->madv == I915_MADV_WILLNEED)
 				mark_page_accessed(page);
-			page_cache_release(page);
+			put_page(page);
 			vaddr += PAGE_SIZE;
 		}
 		obj->dirty = 0;
@@ -2206,7 +2206,7 @@ i915_gem_object_put_pages_gtt(struct drm_i915_gem_object *obj)
 		if (obj->madv == I915_MADV_WILLNEED)
 			mark_page_accessed(page);
 
-		page_cache_release(page);
+		put_page(page);
 	}
 	obj->dirty = 0;
 
@@ -2346,7 +2346,7 @@ i915_gem_object_get_pages_gtt(struct drm_i915_gem_object *obj)
 err_pages:
 	sg_mark_end(sg);
 	for_each_sg_page(st->sgl, &sg_iter, st->nents, 0)
-		page_cache_release(sg_page_iter_page(&sg_iter));
+		put_page(sg_page_iter_page(&sg_iter));
 	sg_free_table(st);
 	kfree(st);
 
diff --git a/drivers/gpu/drm/i915/i915_gem_userptr.c b/drivers/gpu/drm/i915/i915_gem_userptr.c
index 6be40f3ba2c7..18ba8139e922 100644
--- a/drivers/gpu/drm/i915/i915_gem_userptr.c
+++ b/drivers/gpu/drm/i915/i915_gem_userptr.c
@@ -683,7 +683,7 @@ i915_gem_userptr_put_pages(struct drm_i915_gem_object *obj)
 			set_page_dirty(page);
 
 		mark_page_accessed(page);
-		page_cache_release(page);
+		put_page(page);
 	}
 	obj->dirty = 0;
 
diff --git a/drivers/gpu/drm/radeon/radeon_ttm.c b/drivers/gpu/drm/radeon/radeon_ttm.c
index 6d8c32377c6f..0deb7f047be0 100644
--- a/drivers/gpu/drm/radeon/radeon_ttm.c
+++ b/drivers/gpu/drm/radeon/radeon_ttm.c
@@ -609,7 +609,7 @@ static void radeon_ttm_tt_unpin_userptr(struct ttm_tt *ttm)
 			set_page_dirty(page);
 
 		mark_page_accessed(page);
-		page_cache_release(page);
+		put_page(page);
 	}
 
 	sg_free_table(ttm->sg);
diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c
index 4e19d0f9cc30..077ae9b2865d 100644
--- a/drivers/gpu/drm/ttm/ttm_tt.c
+++ b/drivers/gpu/drm/ttm/ttm_tt.c
@@ -311,7 +311,7 @@ int ttm_tt_swapin(struct ttm_tt *ttm)
 			goto out_err;
 
 		copy_highpage(to_page, from_page);
-		page_cache_release(from_page);
+		put_page(from_page);
 	}
 
 	if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP))
@@ -361,7 +361,7 @@ int ttm_tt_swapout(struct ttm_tt *ttm, struct file *persistent_swap_storage)
 		copy_highpage(to_page, from_page);
 		set_page_dirty(to_page);
 		mark_page_accessed(to_page);
-		page_cache_release(to_page);
+		put_page(to_page);
 	}
 
 	ttm_tt_unpopulate(ttm);
diff --git a/drivers/gpu/drm/via/via_dmablit.c b/drivers/gpu/drm/via/via_dmablit.c
index e797dfc07ae3..7e2a12c4fed2 100644
--- a/drivers/gpu/drm/via/via_dmablit.c
+++ b/drivers/gpu/drm/via/via_dmablit.c
@@ -188,7 +188,7 @@ via_free_sg_info(struct pci_dev *pdev, drm_via_sg_info_t *vsg)
 			if (NULL != (page = vsg->pages[i])) {
 				if (!PageReserved(page) && (DMA_FROM_DEVICE == vsg->direction))
 					SetPageDirty(page);
-				page_cache_release(page);
+				put_page(page);
 			}
 		}
 	case dr_via_pages_alloc: