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, 58 insertions, 58 deletions

diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
index 1831f63..a550289 100644
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -269,7 +269,7 @@ static void _ceph_msgr_exit(void)
 	}
 
 	BUG_ON(zero_page == NULL);
-	page_cache_release(zero_page);
+	put_page(zero_page);
 	zero_page = NULL;
 
 	ceph_msgr_slab_exit();
@@ -282,7 +282,7 @@ int ceph_msgr_init(void)
 
 	BUG_ON(zero_page != NULL);
 	zero_page = ZERO_PAGE(0);
-	page_cache_get(zero_page);
+	get_page(zero_page);
 
 	/*
 	 * The number of active work items is limited by the number of
@@ -1602,7 +1602,7 @@ static int write_partial_skip(struct ceph_connection *con)
 
 	dout("%s %p %d left\n", __func__, con, con->out_skip);
 	while (con->out_skip > 0) {
-		size_t size = min(con->out_skip, (int) PAGE_CACHE_SIZE);
+		size_t size = min(con->out_skip, (int) PAGE_SIZE);
 
 		ret = ceph_tcp_sendpage(con->sock, zero_page, 0, size, true);
 		if (ret <= 0)
diff --git a/net/ceph/pagelist.c b/net/ceph/pagelist.c
index c7c220a..6864007 100644
--- a/net/ceph/pagelist.c
+++ b/net/ceph/pagelist.c
@@ -56,7 +56,7 @@ int ceph_pagelist_append(struct ceph_pagelist *pl, const void *buf, size_t len)
 		size_t bit = pl->room;
 		int ret;
 
-		memcpy(pl->mapped_tail + (pl->length & ~PAGE_CACHE_MASK),
+		memcpy(pl->mapped_tail + (pl->length & ~PAGE_MASK),
 		       buf, bit);
 		pl->length += bit;
 		pl->room -= bit;
@@ -67,7 +67,7 @@ int ceph_pagelist_append(struct ceph_pagelist *pl, const void *buf, size_t len)
 			return ret;
 	}
 
-	memcpy(pl->mapped_tail + (pl->length & ~PAGE_CACHE_MASK), buf, len);
+	memcpy(pl->mapped_tail + (pl->length & ~PAGE_MASK), buf, len);
 	pl->length += len;
 	pl->room -= len;
 	return 0;
diff --git a/net/ceph/pagevec.c b/net/ceph/pagevec.c
index 10297f7..00d2601 100644
--- a/net/ceph/pagevec.c
+++ b/net/ceph/pagevec.c
@@ -95,19 +95,19 @@ int ceph_copy_user_to_page_vector(struct page **pages,
 					 loff_t off, size_t len)
 {
 	int i = 0;
-	int po = off & ~PAGE_CACHE_MASK;
+	int po = off & ~PAGE_MASK;
 	int left = len;
 	int l, bad;
 
 	while (left > 0) {
-		l = min_t(int, PAGE_CACHE_SIZE-po, left);
+		l = min_t(int, PAGE_SIZE-po, left);
 		bad = copy_from_user(page_address(pages[i]) + po, data, l);
 		if (bad == l)
 			return -EFAULT;
 		data += l - bad;
 		left -= l - bad;
 		po += l - bad;
-		if (po == PAGE_CACHE_SIZE) {
+		if (po == PAGE_SIZE) {
 			po = 0;
 			i++;
 		}
@@ -121,17 +121,17 @@ void ceph_copy_to_page_vector(struct page **pages,
 				    loff_t off, size_t len)
 {
 	int i = 0;
-	size_t po = off & ~PAGE_CACHE_MASK;
+	size_t po = off & ~PAGE_MASK;
 	size_t left = len;
 
 	while (left > 0) {
-		size_t l = min_t(size_t, PAGE_CACHE_SIZE-po, left);
+		size_t l = min_t(size_t, PAGE_SIZE-po, left);
 
 		memcpy(page_address(pages[i]) + po, data, l);
 		data += l;
 		left -= l;
 		po += l;
-		if (po == PAGE_CACHE_SIZE) {
+		if (po == PAGE_SIZE) {
 			po = 0;
 			i++;
 		}
@@ -144,17 +144,17 @@ void ceph_copy_from_page_vector(struct page **pages,
 				    loff_t off, size_t len)
 {
 	int i = 0;
-	size_t po = off & ~PAGE_CACHE_MASK;
+	size_t po = off & ~PAGE_MASK;
 	size_t left = len;
 
 	while (left > 0) {
-		size_t l = min_t(size_t, PAGE_CACHE_SIZE-po, left);
+		size_t l = min_t(size_t, PAGE_SIZE-po, left);
 
 		memcpy(data, page_address(pages[i]) + po, l);
 		data += l;
 		left -= l;
 		po += l;
-		if (po == PAGE_CACHE_SIZE) {
+		if (po == PAGE_SIZE) {
 			po = 0;
 			i++;
 		}
@@ -168,25 +168,25 @@ EXPORT_SYMBOL(ceph_copy_from_page_vector);
  */
 void ceph_zero_page_vector_range(int off, int len, struct page **pages)
 {
-	int i = off >> PAGE_CACHE_SHIFT;
+	int i = off >> PAGE_SHIFT;
 
-	off &= ~PAGE_CACHE_MASK;
+	off &= ~PAGE_MASK;
 
 	dout("zero_page_vector_page %u~%u\n", off, len);
 
 	/* leading partial page? */
 	if (off) {
-		int end = min((int)PAGE_CACHE_SIZE, off + len);
+		int end = min((int)PAGE_SIZE, off + len);
 		dout("zeroing %d %p head from %d\n", i, pages[i],
 		     (int)off);
 		zero_user_segment(pages[i], off, end);
 		len -= (end - off);
 		i++;
 	}
-	while (len >= PAGE_CACHE_SIZE) {
+	while (len >= PAGE_SIZE) {
 		dout("zeroing %d %p len=%d\n", i, pages[i], len);
-		zero_user_segment(pages[i], 0, PAGE_CACHE_SIZE);
-		len -= PAGE_CACHE_SIZE;
+		zero_user_segment(pages[i], 0, PAGE_SIZE);
+		len -= PAGE_SIZE;
 		i++;
 	}
 	/* trailing partial page? */
diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
index 8c6bc79..15612ff 100644
--- a/net/sunrpc/auth_gss/auth_gss.c
+++ b/net/sunrpc/auth_gss/auth_gss.c
@@ -1728,8 +1728,8 @@ alloc_enc_pages(struct rpc_rqst *rqstp)
 		return 0;
 	}
 
-	first = snd_buf->page_base >> PAGE_CACHE_SHIFT;
-	last = (snd_buf->page_base + snd_buf->page_len - 1) >> PAGE_CACHE_SHIFT;
+	first = snd_buf->page_base >> PAGE_SHIFT;
+	last = (snd_buf->page_base + snd_buf->page_len - 1) >> PAGE_SHIFT;
 	rqstp->rq_enc_pages_num = last - first + 1 + 1;
 	rqstp->rq_enc_pages
 		= kmalloc(rqstp->rq_enc_pages_num * sizeof(struct page *),
@@ -1775,10 +1775,10 @@ gss_wrap_req_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
 	status = alloc_enc_pages(rqstp);
 	if (status)
 		return status;
-	first = snd_buf->page_base >> PAGE_CACHE_SHIFT;
+	first = snd_buf->page_base >> PAGE_SHIFT;
 	inpages = snd_buf->pages + first;
 	snd_buf->pages = rqstp->rq_enc_pages;
-	snd_buf->page_base -= first << PAGE_CACHE_SHIFT;
+	snd_buf->page_base -= first << PAGE_SHIFT;
 	/*
 	 * Give the tail its own page, in case we need extra space in the
 	 * head when wrapping:
diff --git a/net/sunrpc/auth_gss/gss_krb5_crypto.c b/net/sunrpc/auth_gss/gss_krb5_crypto.c
index d94a8e1..045e11e 100644
--- a/net/sunrpc/auth_gss/gss_krb5_crypto.c
+++ b/net/sunrpc/auth_gss/gss_krb5_crypto.c
@@ -465,7 +465,7 @@ encryptor(struct scatterlist *sg, void *data)
 	page_pos = desc->pos - outbuf->head[0].iov_len;
 	if (page_pos >= 0 && page_pos < outbuf->page_len) {
 		/* pages are not in place: */
-		int i = (page_pos + outbuf->page_base) >> PAGE_CACHE_SHIFT;
+		int i = (page_pos + outbuf->page_base) >> PAGE_SHIFT;
 		in_page = desc->pages[i];
 	} else {
 		in_page = sg_page(sg);
diff --git a/net/sunrpc/auth_gss/gss_krb5_wrap.c b/net/sunrpc/auth_gss/gss_krb5_wrap.c
index 765088e4..a737c2d 100644
--- a/net/sunrpc/auth_gss/gss_krb5_wrap.c
+++ b/net/sunrpc/auth_gss/gss_krb5_wrap.c
@@ -79,9 +79,9 @@ gss_krb5_remove_padding(struct xdr_buf *buf, int blocksize)
 		len -= buf->head[0].iov_len;
 	if (len <= buf->page_len) {
 		unsigned int last = (buf->page_base + len - 1)
-					>>PAGE_CACHE_SHIFT;
+					>>PAGE_SHIFT;
 		unsigned int offset = (buf->page_base + len - 1)
-					& (PAGE_CACHE_SIZE - 1);
+					& (PAGE_SIZE - 1);
 		ptr = kmap_atomic(buf->pages[last]);
 		pad = *(ptr + offset);
 		kunmap_atomic(ptr);
diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c
index 008c25d..553bf95 100644
--- a/net/sunrpc/cache.c
+++ b/net/sunrpc/cache.c
@@ -881,7 +881,7 @@ static ssize_t cache_downcall(struct address_space *mapping,
 	char *kaddr;
 	ssize_t ret = -ENOMEM;
 
-	if (count >= PAGE_CACHE_SIZE)
+	if (count >= PAGE_SIZE)
 		goto out_slow;
 
 	page = find_or_create_page(mapping, 0, GFP_KERNEL);
@@ -892,7 +892,7 @@ static ssize_t cache_downcall(struct address_space *mapping,
 	ret = cache_do_downcall(kaddr, buf, count, cd);
 	kunmap(page);
 	unlock_page(page);
-	page_cache_release(page);
+	put_page(page);
 	return ret;
 out_slow:
 	return cache_slow_downcall(buf, count, cd);
diff --git a/net/sunrpc/rpc_pipe.c b/net/sunrpc/rpc_pipe.c
index 31789ef..fc48eca 100644
--- a/net/sunrpc/rpc_pipe.c
+++ b/net/sunrpc/rpc_pipe.c
@@ -1390,8 +1390,8 @@ rpc_fill_super(struct super_block *sb, void *data, int silent)
 	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 	int err;
 
-	sb->s_blocksize = PAGE_CACHE_SIZE;
-	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
+	sb->s_blocksize = PAGE_SIZE;
+	sb->s_blocksize_bits = PAGE_SHIFT;
 	sb->s_magic = RPCAUTH_GSSMAGIC;
 	sb->s_op = &s_ops;
 	sb->s_d_op = &simple_dentry_operations;
diff --git a/net/sunrpc/socklib.c b/net/sunrpc/socklib.c
index 2df87f7..de70c78 100644
--- a/net/sunrpc/socklib.c
+++ b/net/sunrpc/socklib.c
@@ -96,8 +96,8 @@ ssize_t xdr_partial_copy_from_skb(struct xdr_buf *xdr, unsigned int base, struct
 	if (base || xdr->page_base) {
 		pglen -= base;
 		base += xdr->page_base;
-		ppage += base >> PAGE_CACHE_SHIFT;
-		base &= ~PAGE_CACHE_MASK;
+		ppage += base >> PAGE_SHIFT;
+		base &= ~PAGE_MASK;
 	}
 	do {
 		char *kaddr;
@@ -113,7 +113,7 @@ ssize_t xdr_partial_copy_from_skb(struct xdr_buf *xdr, unsigned int base, struct
 			}
 		}
 
-		len = PAGE_CACHE_SIZE;
+		len = PAGE_SIZE;
 		kaddr = kmap_atomic(*ppage);
 		if (base) {
 			len -= base;
diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index 4439ac4..1e6aba0 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -181,20 +181,20 @@ _shift_data_right_pages(struct page **pages, size_t pgto_base,
 	pgto_base += len;
 	pgfrom_base += len;
 
-	pgto = pages + (pgto_base >> PAGE_CACHE_SHIFT);
-	pgfrom = pages + (pgfrom_base >> PAGE_CACHE_SHIFT);
+	pgto = pages + (pgto_base >> PAGE_SHIFT);
+	pgfrom = pages + (pgfrom_base >> PAGE_SHIFT);
 
-	pgto_base &= ~PAGE_CACHE_MASK;
-	pgfrom_base &= ~PAGE_CACHE_MASK;
+	pgto_base &= ~PAGE_MASK;
+	pgfrom_base &= ~PAGE_MASK;
 
 	do {
 		/* Are any pointers crossing a page boundary? */
 		if (pgto_base == 0) {
-			pgto_base = PAGE_CACHE_SIZE;
+			pgto_base = PAGE_SIZE;
 			pgto--;
 		}
 		if (pgfrom_base == 0) {
-			pgfrom_base = PAGE_CACHE_SIZE;
+			pgfrom_base = PAGE_SIZE;
 			pgfrom--;
 		}
 
@@ -236,11 +236,11 @@ _copy_to_pages(struct page **pages, size_t pgbase, const char *p, size_t len)
 	char *vto;
 	size_t copy;
 
-	pgto = pages + (pgbase >> PAGE_CACHE_SHIFT);
-	pgbase &= ~PAGE_CACHE_MASK;
+	pgto = pages + (pgbase >> PAGE_SHIFT);
+	pgbase &= ~PAGE_MASK;
 
 	for (;;) {
-		copy = PAGE_CACHE_SIZE - pgbase;
+		copy = PAGE_SIZE - pgbase;
 		if (copy > len)
 			copy = len;
 
@@ -253,7 +253,7 @@ _copy_to_pages(struct page **pages, size_t pgbase, const char *p, size_t len)
 			break;
 
 		pgbase += copy;
-		if (pgbase == PAGE_CACHE_SIZE) {
+		if (pgbase == PAGE_SIZE) {
 			flush_dcache_page(*pgto);
 			pgbase = 0;
 			pgto++;
@@ -280,11 +280,11 @@ _copy_from_pages(char *p, struct page **pages, size_t pgbase, size_t len)
 	char *vfrom;
 	size_t copy;
 
-	pgfrom = pages + (pgbase >> PAGE_CACHE_SHIFT);
-	pgbase &= ~PAGE_CACHE_MASK;
+	pgfrom = pages + (pgbase >> PAGE_SHIFT);
+	pgbase &= ~PAGE_MASK;
 
 	do {
-		copy = PAGE_CACHE_SIZE - pgbase;
+		copy = PAGE_SIZE - pgbase;
 		if (copy > len)
 			copy = len;
 
@@ -293,7 +293,7 @@ _copy_from_pages(char *p, struct page **pages, size_t pgbase, size_t len)
 		kunmap_atomic(vfrom);
 
 		pgbase += copy;
-		if (pgbase == PAGE_CACHE_SIZE) {
+		if (pgbase == PAGE_SIZE) {
 			pgbase = 0;
 			pgfrom++;
 		}
@@ -1038,8 +1038,8 @@ xdr_buf_subsegment(struct xdr_buf *buf, struct xdr_buf *subbuf,
 	if (base < buf->page_len) {
 		subbuf->page_len = min(buf->page_len - base, len);
 		base += buf->page_base;
-		subbuf->page_base = base & ~PAGE_CACHE_MASK;
-		subbuf->pages = &buf->pages[base >> PAGE_CACHE_SHIFT];
+		subbuf->page_base = base & ~PAGE_MASK;
+		subbuf->pages = &buf->pages[base >> PAGE_SHIFT];
 		len -= subbuf->page_len;
 		base = 0;
 	} else {
@@ -1297,9 +1297,9 @@ xdr_xcode_array2(struct xdr_buf *buf, unsigned int base,
 		todo -= avail_here;
 
 		base += buf->page_base;
-		ppages = buf->pages + (base >> PAGE_CACHE_SHIFT);
-		base &= ~PAGE_CACHE_MASK;
-		avail_page = min_t(unsigned int, PAGE_CACHE_SIZE - base,
+		ppages = buf->pages + (base >> PAGE_SHIFT);
+		base &= ~PAGE_MASK;
+		avail_page = min_t(unsigned int, PAGE_SIZE - base,
 					avail_here);
 		c = kmap(*ppages) + base;
 
@@ -1383,7 +1383,7 @@ xdr_xcode_array2(struct xdr_buf *buf, unsigned int base,
 			}
 
 			avail_page = min(avail_here,
-				 (unsigned int) PAGE_CACHE_SIZE);
+				 (unsigned int) PAGE_SIZE);
 		}
 		base = buf->page_len;  /* align to start of tail */
 	}
@@ -1479,9 +1479,9 @@ xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len,
 		if (page_len > len)
 			page_len = len;
 		len -= page_len;
-		page_offset = (offset + buf->page_base) & (PAGE_CACHE_SIZE - 1);
-		i = (offset + buf->page_base) >> PAGE_CACHE_SHIFT;
-		thislen = PAGE_CACHE_SIZE - page_offset;
+		page_offset = (offset + buf->page_base) & (PAGE_SIZE - 1);
+		i = (offset + buf->page_base) >> PAGE_SHIFT;
+		thislen = PAGE_SIZE - page_offset;
 		do {
 			if (thislen > page_len)
 				thislen = page_len;
@@ -1492,7 +1492,7 @@ xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len,
 			page_len -= thislen;
 			i++;
 			page_offset = 0;
-			thislen = PAGE_CACHE_SIZE;
+			thislen = PAGE_SIZE;
 		} while (page_len != 0);
 		offset = 0;
 	}