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>

10 files changed, 46 insertions, 46 deletions

diff --git a/fs/nilfs2/bmap.c b/fs/nilfs2/bmap.c
index 27f75bcbeb30..a9fb3636c142 100644
--- a/fs/nilfs2/bmap.c
+++ b/fs/nilfs2/bmap.c
@@ -458,7 +458,7 @@ __u64 nilfs_bmap_data_get_key(const struct nilfs_bmap *bmap,
         struct buffer_head *pbh;
         __u64 key;
 
-        key = page_index(bh->b_page) << (PAGE_CACHE_SHIFT -
+        key = page_index(bh->b_page) << (PAGE_SHIFT -
                                          bmap->b_inode->i_blkbits);
         for (pbh = page_buffers(bh->b_page); pbh != bh; pbh = pbh->b_this_page)
                 key++;
diff --git a/fs/nilfs2/btnode.c b/fs/nilfs2/btnode.c
index a35ae35e6932..e0c9daf9aa22 100644
--- a/fs/nilfs2/btnode.c
+++ b/fs/nilfs2/btnode.c
@@ -62,7 +62,7 @@ nilfs_btnode_create_block(struct address_space *btnc, __u64 blocknr)
         set_buffer_uptodate(bh);
 
         unlock_page(bh->b_page);
-        page_cache_release(bh->b_page);
+        put_page(bh->b_page);
         return bh;
 }
 
@@ -128,7 +128,7 @@ found:
 
 out_locked:
         unlock_page(page);
-        page_cache_release(page);
+        put_page(page);
         return err;
 }
 
@@ -146,7 +146,7 @@ void nilfs_btnode_delete(struct buffer_head *bh)
         pgoff_t index = page_index(page);
         int still_dirty;
 
-        page_cache_get(page);
+        get_page(page);
         lock_page(page);
         wait_on_page_writeback(page);
 
@@ -154,7 +154,7 @@ void nilfs_btnode_delete(struct buffer_head *bh)
         still_dirty = PageDirty(page);
         mapping = page->mapping;
         unlock_page(page);
-        page_cache_release(page);
+        put_page(page);
 
         if (!still_dirty && mapping)
                 invalidate_inode_pages2_range(mapping, index, index);
@@ -181,7 +181,7 @@ int nilfs_btnode_prepare_change_key(struct address_space *btnc,
         obh = ctxt->bh;
         ctxt->newbh = NULL;
 
-        if (inode->i_blkbits == PAGE_CACHE_SHIFT) {
+        if (inode->i_blkbits == PAGE_SHIFT) {
                 lock_page(obh->b_page);
                 /*
                  * We cannot call radix_tree_preload for the kernels older
diff --git a/fs/nilfs2/dir.c b/fs/nilfs2/dir.c
index 6b8b92b19cec..e08f064e4bd7 100644
--- a/fs/nilfs2/dir.c
+++ b/fs/nilfs2/dir.c
@@ -58,7 +58,7 @@ static inline unsigned nilfs_chunk_size(struct inode *inode)
 static inline void nilfs_put_page(struct page *page)
 {
         kunmap(page);
-        page_cache_release(page);
+        put_page(page);
 }
 
 /*
@@ -69,9 +69,9 @@ static unsigned nilfs_last_byte(struct inode *inode, unsigned long page_nr)
 {
         unsigned last_byte = inode->i_size;
 
-        last_byte -= page_nr << PAGE_CACHE_SHIFT;
-        if (last_byte > PAGE_CACHE_SIZE)
-                last_byte = PAGE_CACHE_SIZE;
+        last_byte -= page_nr << PAGE_SHIFT;
+        if (last_byte > PAGE_SIZE)
+                last_byte = PAGE_SIZE;
         return last_byte;
 }
 
@@ -109,12 +109,12 @@ static void nilfs_check_page(struct page *page)
         unsigned chunk_size = nilfs_chunk_size(dir);
         char *kaddr = page_address(page);
         unsigned offs, rec_len;
-        unsigned limit = PAGE_CACHE_SIZE;
+        unsigned limit = PAGE_SIZE;
         struct nilfs_dir_entry *p;
         char *error;
 
-        if ((dir->i_size >> PAGE_CACHE_SHIFT) == page->index) {
-                limit = dir->i_size & ~PAGE_CACHE_MASK;
+        if ((dir->i_size >> PAGE_SHIFT) == page->index) {
+                limit = dir->i_size & ~PAGE_MASK;
                 if (limit & (chunk_size - 1))
                         goto Ebadsize;
                 if (!limit)
@@ -161,7 +161,7 @@ Espan:
 bad_entry:
         nilfs_error(sb, "nilfs_check_page", "bad entry in directory #%lu: %s - "
                     "offset=%lu, inode=%lu, rec_len=%d, name_len=%d",
-                    dir->i_ino, error, (page->index<<PAGE_CACHE_SHIFT)+offs,
+                    dir->i_ino, error, (page->index<<PAGE_SHIFT)+offs,
                     (unsigned long) le64_to_cpu(p->inode),
                     rec_len, p->name_len);
         goto fail;
@@ -170,7 +170,7 @@ Eend:
         nilfs_error(sb, "nilfs_check_page",
                     "entry in directory #%lu spans the page boundary"
                     "offset=%lu, inode=%lu",
-                    dir->i_ino, (page->index<<PAGE_CACHE_SHIFT)+offs,
+                    dir->i_ino, (page->index<<PAGE_SHIFT)+offs,
                     (unsigned long) le64_to_cpu(p->inode));
 fail:
         SetPageChecked(page);
@@ -256,8 +256,8 @@ static int nilfs_readdir(struct file *file, struct dir_context *ctx)
         loff_t pos = ctx->pos;
         struct inode *inode = file_inode(file);
         struct super_block *sb = inode->i_sb;
-        unsigned int offset = pos & ~PAGE_CACHE_MASK;
-        unsigned long n = pos >> PAGE_CACHE_SHIFT;
+        unsigned int offset = pos & ~PAGE_MASK;
+        unsigned long n = pos >> PAGE_SHIFT;
         unsigned long npages = dir_pages(inode);
 /*      unsigned chunk_mask = ~(nilfs_chunk_size(inode)-1); */
 
@@ -272,7 +272,7 @@ static int nilfs_readdir(struct file *file, struct dir_context *ctx)
                 if (IS_ERR(page)) {
                         nilfs_error(sb, __func__, "bad page in #%lu",
                                     inode->i_ino);
-                        ctx->pos += PAGE_CACHE_SIZE - offset;
+                        ctx->pos += PAGE_SIZE - offset;
                         return -EIO;
                 }
                 kaddr = page_address(page);
@@ -361,7 +361,7 @@ nilfs_find_entry(struct inode *dir, const struct qstr *qstr,
                 if (++n >= npages)
                         n = 0;
                 /* next page is past the blocks we've got */
-                if (unlikely(n > (dir->i_blocks >> (PAGE_CACHE_SHIFT - 9)))) {
+                if (unlikely(n > (dir->i_blocks >> (PAGE_SHIFT - 9)))) {
                         nilfs_error(dir->i_sb, __func__,
                                "dir %lu size %lld exceeds block count %llu",
                                dir->i_ino, dir->i_size,
@@ -401,7 +401,7 @@ ino_t nilfs_inode_by_name(struct inode *dir, const struct qstr *qstr)
         if (de) {
                 res = le64_to_cpu(de->inode);
                 kunmap(page);
-                page_cache_release(page);
+                put_page(page);
         }
         return res;
 }
@@ -460,7 +460,7 @@ int nilfs_add_link(struct dentry *dentry, struct inode *inode)
                 kaddr = page_address(page);
                 dir_end = kaddr + nilfs_last_byte(dir, n);
                 de = (struct nilfs_dir_entry *)kaddr;
-                kaddr += PAGE_CACHE_SIZE - reclen;
+                kaddr += PAGE_SIZE - reclen;
                 while ((char *)de <= kaddr) {
                         if ((char *)de == dir_end) {
                                 /* We hit i_size */
@@ -603,7 +603,7 @@ int nilfs_make_empty(struct inode *inode, struct inode *parent)
         kunmap_atomic(kaddr);
         nilfs_commit_chunk(page, mapping, 0, chunk_size);
 fail:
-        page_cache_release(page);
+        put_page(page);
         return err;
 }
 
diff --git a/fs/nilfs2/gcinode.c b/fs/nilfs2/gcinode.c
index 748ca238915a..0224b7826ace 100644
--- a/fs/nilfs2/gcinode.c
+++ b/fs/nilfs2/gcinode.c
@@ -115,7 +115,7 @@ int nilfs_gccache_submit_read_data(struct inode *inode, sector_t blkoff,
 
  failed:
         unlock_page(bh->b_page);
-        page_cache_release(bh->b_page);
+        put_page(bh->b_page);
         return err;
 }
 
diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c
index 21a1e2e0d92f..534631358b13 100644
--- a/fs/nilfs2/inode.c
+++ b/fs/nilfs2/inode.c
@@ -249,7 +249,7 @@ static int nilfs_set_page_dirty(struct page *page)
                 if (nr_dirty)
                         nilfs_set_file_dirty(inode, nr_dirty);
         } else if (ret) {
-                unsigned nr_dirty = 1 << (PAGE_CACHE_SHIFT - inode->i_blkbits);
+                unsigned nr_dirty = 1 << (PAGE_SHIFT - inode->i_blkbits);
 
                 nilfs_set_file_dirty(inode, nr_dirty);
         }
@@ -291,7 +291,7 @@ static int nilfs_write_end(struct file *file, struct address_space *mapping,
                            struct page *page, void *fsdata)
 {
         struct inode *inode = mapping->host;
-        unsigned start = pos & (PAGE_CACHE_SIZE - 1);
+        unsigned start = pos & (PAGE_SIZE - 1);
         unsigned nr_dirty;
         int err;
 
diff --git a/fs/nilfs2/mdt.c b/fs/nilfs2/mdt.c
index 1125f40233ff..f6982b9153d5 100644
--- a/fs/nilfs2/mdt.c
+++ b/fs/nilfs2/mdt.c
@@ -110,7 +110,7 @@ static int nilfs_mdt_create_block(struct inode *inode, unsigned long block,
 
  failed_bh:
         unlock_page(bh->b_page);
-        page_cache_release(bh->b_page);
+        put_page(bh->b_page);
         brelse(bh);
 
  failed_unlock:
@@ -170,7 +170,7 @@ nilfs_mdt_submit_block(struct inode *inode, unsigned long blkoff,
 
  failed_bh:
         unlock_page(bh->b_page);
-        page_cache_release(bh->b_page);
+        put_page(bh->b_page);
         brelse(bh);
  failed:
         return ret;
@@ -363,7 +363,7 @@ int nilfs_mdt_delete_block(struct inode *inode, unsigned long block)
 int nilfs_mdt_forget_block(struct inode *inode, unsigned long block)
 {
         pgoff_t index = (pgoff_t)block >>
-                (PAGE_CACHE_SHIFT - inode->i_blkbits);
+                (PAGE_SHIFT - inode->i_blkbits);
         struct page *page;
         unsigned long first_block;
         int ret = 0;
@@ -376,7 +376,7 @@ int nilfs_mdt_forget_block(struct inode *inode, unsigned long block)
         wait_on_page_writeback(page);
 
         first_block = (unsigned long)index <<
-                (PAGE_CACHE_SHIFT - inode->i_blkbits);
+                (PAGE_SHIFT - inode->i_blkbits);
         if (page_has_buffers(page)) {
                 struct buffer_head *bh;
 
@@ -385,7 +385,7 @@ int nilfs_mdt_forget_block(struct inode *inode, unsigned long block)
         }
         still_dirty = PageDirty(page);
         unlock_page(page);
-        page_cache_release(page);
+        put_page(page);
 
         if (still_dirty ||
             invalidate_inode_pages2_range(inode->i_mapping, index, index) != 0)
@@ -578,7 +578,7 @@ int nilfs_mdt_freeze_buffer(struct inode *inode, struct buffer_head *bh)
         }
 
         unlock_page(page);
-        page_cache_release(page);
+        put_page(page);
         return 0;
 }
 
@@ -597,7 +597,7 @@ nilfs_mdt_get_frozen_buffer(struct inode *inode, struct buffer_head *bh)
                         bh_frozen = nilfs_page_get_nth_block(page, n);
                 }
                 unlock_page(page);
-                page_cache_release(page);
+                put_page(page);
         }
         return bh_frozen;
 }
diff --git a/fs/nilfs2/namei.c b/fs/nilfs2/namei.c
index 7ccdb961eea9..151bc19d47c0 100644
--- a/fs/nilfs2/namei.c
+++ b/fs/nilfs2/namei.c
@@ -431,11 +431,11 @@ static int nilfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 out_dir:
         if (dir_de) {
                 kunmap(dir_page);
-                page_cache_release(dir_page);
+                put_page(dir_page);
         }
 out_old:
         kunmap(old_page);
-        page_cache_release(old_page);
+        put_page(old_page);
 out:
         nilfs_transaction_abort(old_dir->i_sb);
         return err;
diff --git a/fs/nilfs2/page.c b/fs/nilfs2/page.c
index c20df77eff99..489391561cda 100644
--- a/fs/nilfs2/page.c
+++ b/fs/nilfs2/page.c
@@ -50,7 +50,7 @@ __nilfs_get_page_block(struct page *page, unsigned long block, pgoff_t index,
         if (!page_has_buffers(page))
                 create_empty_buffers(page, 1 << blkbits, b_state);
 
-        first_block = (unsigned long)index << (PAGE_CACHE_SHIFT - blkbits);
+        first_block = (unsigned long)index << (PAGE_SHIFT - blkbits);
         bh = nilfs_page_get_nth_block(page, block - first_block);
 
         touch_buffer(bh);
@@ -64,7 +64,7 @@ struct buffer_head *nilfs_grab_buffer(struct inode *inode,
                                       unsigned long b_state)
 {
         int blkbits = inode->i_blkbits;
-        pgoff_t index = blkoff >> (PAGE_CACHE_SHIFT - blkbits);
+        pgoff_t index = blkoff >> (PAGE_SHIFT - blkbits);
         struct page *page;
         struct buffer_head *bh;
 
@@ -75,7 +75,7 @@ struct buffer_head *nilfs_grab_buffer(struct inode *inode,
         bh = __nilfs_get_page_block(page, blkoff, index, blkbits, b_state);
         if (unlikely(!bh)) {
                 unlock_page(page);
-                page_cache_release(page);
+                put_page(page);
                 return NULL;
         }
         return bh;
@@ -288,7 +288,7 @@ repeat:
                 __set_page_dirty_nobuffers(dpage);
 
                 unlock_page(dpage);
-                page_cache_release(dpage);
+                put_page(dpage);
                 unlock_page(page);
         }
         pagevec_release(&pvec);
@@ -333,7 +333,7 @@ repeat:
                         WARN_ON(PageDirty(dpage));
                         nilfs_copy_page(dpage, page, 0);
                         unlock_page(dpage);
-                        page_cache_release(dpage);
+                        put_page(dpage);
                 } else {
                         struct page *page2;
 
@@ -350,7 +350,7 @@ repeat:
                         if (unlikely(err < 0)) {
                                 WARN_ON(err == -EEXIST);
                                 page->mapping = NULL;
-                                page_cache_release(page); /* for cache */
+                                put_page(page); /* for cache */
                         } else {
                                 page->mapping = dmap;
                                 dmap->nrpages++;
@@ -523,8 +523,8 @@ unsigned long nilfs_find_uncommitted_extent(struct inode *inode,
         if (inode->i_mapping->nrpages == 0)
                 return 0;
 
-        index = start_blk >> (PAGE_CACHE_SHIFT - inode->i_blkbits);
-        nblocks_in_page = 1U << (PAGE_CACHE_SHIFT - inode->i_blkbits);
+        index = start_blk >> (PAGE_SHIFT - inode->i_blkbits);
+        nblocks_in_page = 1U << (PAGE_SHIFT - inode->i_blkbits);
 
         pagevec_init(&pvec, 0);
 
@@ -537,7 +537,7 @@ repeat:
         if (length > 0 && pvec.pages[0]->index > index)
                 goto out;
 
-        b = pvec.pages[0]->index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
+        b = pvec.pages[0]->index << (PAGE_SHIFT - inode->i_blkbits);
         i = 0;
         do {
                 page = pvec.pages[i];
diff --git a/fs/nilfs2/recovery.c b/fs/nilfs2/recovery.c
index 9b4f205d1173..5afa77fadc11 100644
--- a/fs/nilfs2/recovery.c
+++ b/fs/nilfs2/recovery.c
@@ -544,14 +544,14 @@ static int nilfs_recover_dsync_blocks(struct the_nilfs *nilfs,
                                 blocksize, page, NULL);
 
                 unlock_page(page);
-                page_cache_release(page);
+                put_page(page);
 
                 (*nr_salvaged_blocks)++;
                 goto next;
 
  failed_page:
                 unlock_page(page);
-                page_cache_release(page);
+                put_page(page);
 
  failed_inode:
                 printk(KERN_WARNING
diff --git a/fs/nilfs2/segment.c b/fs/nilfs2/segment.c
index 3b65adaae7e4..4317f72568e6 100644
--- a/fs/nilfs2/segment.c
+++ b/fs/nilfs2/segment.c
@@ -2070,7 +2070,7 @@ static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode)
                         goto failed_to_write;
 
                 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE ||
-                    nilfs->ns_blocksize_bits != PAGE_CACHE_SHIFT) {
+                    nilfs->ns_blocksize_bits != PAGE_SHIFT) {
                         /*
                          * At this point, we avoid double buffering
                          * for blocksize < pagesize because page dirty