File-copy from v4.4.100
This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Please refer to that tree for all history prior to this point.
Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/fs/freevxfs/vxfs_subr.c b/fs/freevxfs/vxfs_subr.c
new file mode 100644
index 0000000..5d318c4
--- /dev/null
+++ b/fs/freevxfs/vxfs_subr.c
@@ -0,0 +1,183 @@
+/*
+ * Copyright (c) 2000-2001 Christoph Hellwig.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions, and the following disclaimer,
+ * without modification.
+ * 2. The name of the author may not be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL").
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/*
+ * Veritas filesystem driver - shared subroutines.
+ */
+#include <linux/fs.h>
+#include <linux/buffer_head.h>
+#include <linux/kernel.h>
+#include <linux/pagemap.h>
+
+#include "vxfs_extern.h"
+
+
+static int vxfs_readpage(struct file *, struct page *);
+static sector_t vxfs_bmap(struct address_space *, sector_t);
+
+const struct address_space_operations vxfs_aops = {
+ .readpage = vxfs_readpage,
+ .bmap = vxfs_bmap,
+};
+
+inline void
+vxfs_put_page(struct page *pp)
+{
+ kunmap(pp);
+ page_cache_release(pp);
+}
+
+/**
+ * vxfs_get_page - read a page into memory.
+ * @ip: inode to read from
+ * @n: page number
+ *
+ * Description:
+ * vxfs_get_page reads the @n th page of @ip into the pagecache.
+ *
+ * Returns:
+ * The wanted page on success, else a NULL pointer.
+ */
+struct page *
+vxfs_get_page(struct address_space *mapping, u_long n)
+{
+ struct page * pp;
+
+ pp = read_mapping_page(mapping, n, NULL);
+
+ if (!IS_ERR(pp)) {
+ kmap(pp);
+ /** if (!PageChecked(pp)) **/
+ /** vxfs_check_page(pp); **/
+ if (PageError(pp))
+ goto fail;
+ }
+
+ return (pp);
+
+fail:
+ vxfs_put_page(pp);
+ return ERR_PTR(-EIO);
+}
+
+/**
+ * vxfs_bread - read buffer for a give inode,block tuple
+ * @ip: inode
+ * @block: logical block
+ *
+ * Description:
+ * The vxfs_bread function reads block no @block of
+ * @ip into the buffercache.
+ *
+ * Returns:
+ * The resulting &struct buffer_head.
+ */
+struct buffer_head *
+vxfs_bread(struct inode *ip, int block)
+{
+ struct buffer_head *bp;
+ daddr_t pblock;
+
+ pblock = vxfs_bmap1(ip, block);
+ bp = sb_bread(ip->i_sb, pblock);
+
+ return (bp);
+}
+
+/**
+ * vxfs_get_block - locate buffer for given inode,block tuple
+ * @ip: inode
+ * @iblock: logical block
+ * @bp: buffer skeleton
+ * @create: %TRUE if blocks may be newly allocated.
+ *
+ * Description:
+ * The vxfs_get_block function fills @bp with the right physical
+ * block and device number to perform a lowlevel read/write on
+ * it.
+ *
+ * Returns:
+ * Zero on success, else a negativ error code (-EIO).
+ */
+static int
+vxfs_getblk(struct inode *ip, sector_t iblock,
+ struct buffer_head *bp, int create)
+{
+ daddr_t pblock;
+
+ pblock = vxfs_bmap1(ip, iblock);
+ if (pblock != 0) {
+ map_bh(bp, ip->i_sb, pblock);
+ return 0;
+ }
+
+ return -EIO;
+}
+
+/**
+ * vxfs_readpage - read one page synchronously into the pagecache
+ * @file: file context (unused)
+ * @page: page frame to fill in.
+ *
+ * Description:
+ * The vxfs_readpage routine reads @page synchronously into the
+ * pagecache.
+ *
+ * Returns:
+ * Zero on success, else a negative error code.
+ *
+ * Locking status:
+ * @page is locked and will be unlocked.
+ */
+static int
+vxfs_readpage(struct file *file, struct page *page)
+{
+ return block_read_full_page(page, vxfs_getblk);
+}
+
+/**
+ * vxfs_bmap - perform logical to physical block mapping
+ * @mapping: logical to physical mapping to use
+ * @block: logical block (relative to @mapping).
+ *
+ * Description:
+ * Vxfs_bmap find out the corresponding phsical block to the
+ * @mapping, @block pair.
+ *
+ * Returns:
+ * Physical block number on success, else Zero.
+ *
+ * Locking status:
+ * We are under the bkl.
+ */
+static sector_t
+vxfs_bmap(struct address_space *mapping, sector_t block)
+{
+ return generic_block_bmap(mapping, block, vxfs_getblk);
+}