[PATCH] OCFS2: The Second Oracle Cluster Filesystem

The OCFS2 file system module.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: Kurt Hackel <kurt.hackel@oracle.com>

1 files changed, 1237 insertions, 0 deletions

diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
new file mode 100644
index 0000000..72ae9e3
--- /dev/null
+++ b/fs/ocfs2/file.c
@@ -0,0 +1,1237 @@
+/* -*- mode: c; c-basic-offset: 8; -*-
+ * vim: noexpandtab sw=8 ts=8 sts=0:
+ *
+ * file.c
+ *
+ * File open, close, extend, truncate
+ *
+ * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#include <linux/fs.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/highmem.h>
+#include <linux/pagemap.h>
+#include <linux/uio.h>
+
+#define MLOG_MASK_PREFIX ML_INODE
+#include <cluster/masklog.h>
+
+#include "ocfs2.h"
+
+#include "alloc.h"
+#include "aops.h"
+#include "dir.h"
+#include "dlmglue.h"
+#include "extent_map.h"
+#include "file.h"
+#include "sysfile.h"
+#include "inode.h"
+#include "journal.h"
+#include "mmap.h"
+#include "suballoc.h"
+#include "super.h"
+
+#include "buffer_head_io.h"
+
+static int ocfs2_sync_inode(struct inode *inode)
+{
+	filemap_fdatawrite(inode->i_mapping);
+	return sync_mapping_buffers(inode->i_mapping);
+}
+
+static int ocfs2_file_open(struct inode *inode, struct file *file)
+{
+	int status;
+	int mode = file->f_flags;
+	struct ocfs2_inode_info *oi = OCFS2_I(inode);
+
+	mlog_entry("(0x%p, 0x%p, '%.*s')\n", inode, file,
+		   file->f_dentry->d_name.len, file->f_dentry->d_name.name);
+
+	spin_lock(&oi->ip_lock);
+
+	/* Check that the inode hasn't been wiped from disk by another
+	 * node. If it hasn't then we're safe as long as we hold the
+	 * spin lock until our increment of open count. */
+	if (OCFS2_I(inode)->ip_flags & OCFS2_INODE_DELETED) {
+		spin_unlock(&oi->ip_lock);
+
+		status = -ENOENT;
+		goto leave;
+	}
+
+	if (mode & O_DIRECT)
+		oi->ip_flags |= OCFS2_INODE_OPEN_DIRECT;
+
+	oi->ip_open_count++;
+	spin_unlock(&oi->ip_lock);
+	status = 0;
+leave:
+	mlog_exit(status);
+	return status;
+}
+
+static int ocfs2_file_release(struct inode *inode, struct file *file)
+{
+	struct ocfs2_inode_info *oi = OCFS2_I(inode);
+
+	mlog_entry("(0x%p, 0x%p, '%.*s')\n", inode, file,
+		       file->f_dentry->d_name.len,
+		       file->f_dentry->d_name.name);
+
+	spin_lock(&oi->ip_lock);
+	if (!--oi->ip_open_count)
+		oi->ip_flags &= ~OCFS2_INODE_OPEN_DIRECT;
+	spin_unlock(&oi->ip_lock);
+
+	mlog_exit(0);
+
+	return 0;
+}
+
+static int ocfs2_sync_file(struct file *file,
+			   struct dentry *dentry,
+			   int datasync)
+{
+	int err = 0;
+	journal_t *journal;
+	struct inode *inode = dentry->d_inode;
+	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+
+	mlog_entry("(0x%p, 0x%p, %d, '%.*s')\n", file, dentry, datasync,
+		   dentry->d_name.len, dentry->d_name.name);
+
+	err = ocfs2_sync_inode(dentry->d_inode);
+	if (err)
+		goto bail;
+
+	journal = osb->journal->j_journal;
+	err = journal_force_commit(journal);
+
+bail:
+	mlog_exit(err);
+
+	return (err < 0) ? -EIO : 0;
+}
+
+int ocfs2_set_inode_size(struct ocfs2_journal_handle *handle,
+			 struct inode *inode,
+			 struct buffer_head *fe_bh,
+			 u64 new_i_size)
+{
+	int status;
+
+	mlog_entry_void();
+	i_size_write(inode, new_i_size);
+	inode->i_blocks = ocfs2_align_bytes_to_sectors(new_i_size);
+	inode->i_ctime = inode->i_mtime = CURRENT_TIME;
+
+	status = ocfs2_mark_inode_dirty(handle, inode, fe_bh);
+	if (status < 0) {
+		mlog_errno(status);
+		goto bail;
+	}
+
+bail:
+	mlog_exit(status);
+	return status;
+}
+
+static int ocfs2_simple_size_update(struct inode *inode,
+				    struct buffer_head *di_bh,
+				    u64 new_i_size)
+{
+	int ret;
+	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+	struct ocfs2_journal_handle *handle = NULL;
+
+	handle = ocfs2_start_trans(osb, NULL,
+				   OCFS2_INODE_UPDATE_CREDITS);
+	if (handle == NULL) {
+		ret = -ENOMEM;
+		mlog_errno(ret);
+		goto out;
+	}
+
+	ret = ocfs2_set_inode_size(handle, inode, di_bh,
+				   new_i_size);
+	if (ret < 0)
+		mlog_errno(ret);
+
+	ocfs2_commit_trans(handle);
+out:
+	return ret;
+}
+
+static int ocfs2_orphan_for_truncate(struct ocfs2_super *osb,
+				     struct inode *inode,
+				     struct buffer_head *fe_bh,
+				     u64 new_i_size)
+{
+	int status;
+	struct ocfs2_journal_handle *handle;
+
+	mlog_entry_void();
+
+	/* TODO: This needs to actually orphan the inode in this
+	 * transaction. */
+
+	handle = ocfs2_start_trans(osb, NULL, OCFS2_INODE_UPDATE_CREDITS);
+	if (IS_ERR(handle)) {
+		status = PTR_ERR(handle);
+		mlog_errno(status);
+		goto out;
+	}
+
+	status = ocfs2_set_inode_size(handle, inode, fe_bh, new_i_size);
+	if (status < 0)
+		mlog_errno(status);
+
+	ocfs2_commit_trans(handle);
+out:
+	mlog_exit(status);
+	return status;
+}
+
+static int ocfs2_truncate_file(struct inode *inode,
+			       struct buffer_head *di_bh,
+			       u64 new_i_size)
+{
+	int status = 0;
+	struct ocfs2_dinode *fe = NULL;
+	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+	struct ocfs2_truncate_context *tc = NULL;
+
+	mlog_entry("(inode = %"MLFu64", new_i_size = %"MLFu64"\n",
+		   OCFS2_I(inode)->ip_blkno, new_i_size);
+
+	truncate_inode_pages(inode->i_mapping, new_i_size);
+
+	fe = (struct ocfs2_dinode *) di_bh->b_data;
+	if (!OCFS2_IS_VALID_DINODE(fe)) {
+		OCFS2_RO_ON_INVALID_DINODE(inode->i_sb, fe);
+		status = -EIO;
+		goto bail;
+	}
+
+	mlog_bug_on_msg(le64_to_cpu(fe->i_size) != i_size_read(inode),
+			"Inode %"MLFu64", inode i_size = %lld != di "
+			"i_size = %"MLFu64", i_flags = 0x%x\n",
+			OCFS2_I(inode)->ip_blkno,
+			i_size_read(inode),
+			le64_to_cpu(fe->i_size), le32_to_cpu(fe->i_flags));
+
+	if (new_i_size > le64_to_cpu(fe->i_size)) {
+		mlog(0, "asked to truncate file with size (%"MLFu64") "
+		     "to size (%"MLFu64")!\n",
+		     le64_to_cpu(fe->i_size), new_i_size);
+		status = -EINVAL;
+		mlog_errno(status);
+		goto bail;
+	}
+
+	mlog(0, "inode %"MLFu64", i_size = %"MLFu64", new_i_size = %"MLFu64"\n",
+	     le64_to_cpu(fe->i_blkno), le64_to_cpu(fe->i_size), new_i_size);
+
+	/* lets handle the simple truncate cases before doing any more
+	 * cluster locking. */
+	if (new_i_size == le64_to_cpu(fe->i_size))
+		goto bail;
+
+	if (le32_to_cpu(fe->i_clusters) ==
+	    ocfs2_clusters_for_bytes(osb->sb, new_i_size)) {
+		mlog(0, "fe->i_clusters = %u, so we do a simple truncate\n",
+		     fe->i_clusters);
+		/* No allocation change is required, so lets fast path
+		 * this truncate. */
+		status = ocfs2_simple_size_update(inode, di_bh, new_i_size);
+		if (status < 0)
+			mlog_errno(status);
+		goto bail;
+	}
+
+	/* This forces other nodes to sync and drop their pages */
+	status = ocfs2_data_lock(inode, 1);
+	if (status < 0) {
+		mlog_errno(status);
+		goto bail;
+	}
+	ocfs2_data_unlock(inode, 1);
+
+	/* alright, we're going to need to do a full blown alloc size
+	 * change. Orphan the inode so that recovery can complete the
+	 * truncate if necessary. This does the task of marking
+	 * i_size. */
+	status = ocfs2_orphan_for_truncate(osb, inode, di_bh, new_i_size);
+	if (status < 0) {
+		mlog_errno(status);
+		goto bail;
+	}
+
+	status = ocfs2_prepare_truncate(osb, inode, di_bh, &tc);
+	if (status < 0) {
+		mlog_errno(status);
+		goto bail;
+	}
+
+	status = ocfs2_commit_truncate(osb, inode, di_bh, tc);
+	if (status < 0) {
+		mlog_errno(status);
+		goto bail;
+	}
+
+	/* TODO: orphan dir cleanup here. */
+bail:
+
+	mlog_exit(status);
+	return status;
+}
+
+/*
+ * extend allocation only here.
+ * we'll update all the disk stuff, and oip->alloc_size
+ *
+ * expect stuff to be locked, a transaction started and enough data /
+ * metadata reservations in the contexts.
+ *
+ * Will return -EAGAIN, and a reason if a restart is needed.
+ * If passed in, *reason will always be set, even in error.
+ */
+int ocfs2_do_extend_allocation(struct ocfs2_super *osb,
+			       struct inode *inode,
+			       u32 clusters_to_add,
+			       struct buffer_head *fe_bh,
+			       struct ocfs2_journal_handle *handle,
+			       struct ocfs2_alloc_context *data_ac,
+			       struct ocfs2_alloc_context *meta_ac,
+			       enum ocfs2_alloc_restarted *reason_ret)
+{
+	int status = 0;
+	int free_extents;
+	struct ocfs2_dinode *fe = (struct ocfs2_dinode *) fe_bh->b_data;
+	enum ocfs2_alloc_restarted reason = RESTART_NONE;
+	u32 bit_off, num_bits;
+	u64 block;
+
+	BUG_ON(!clusters_to_add);
+
+	free_extents = ocfs2_num_free_extents(osb, inode, fe);
+	if (free_extents < 0) {
+		status = free_extents;
+		mlog_errno(status);
+		goto leave;
+	}
+
+	/* there are two cases which could cause us to EAGAIN in the
+	 * we-need-more-metadata case:
+	 * 1) we haven't reserved *any*
+	 * 2) we are so fragmented, we've needed to add metadata too
+	 *    many times. */
+	if (!free_extents && !meta_ac) {
+		mlog(0, "we haven't reserved any metadata!\n");
+		status = -EAGAIN;
+		reason = RESTART_META;
+		goto leave;
+	} else if ((!free_extents)
+		   && (ocfs2_alloc_context_bits_left(meta_ac)
+		       < ocfs2_extend_meta_needed(fe))) {
+		mlog(0, "filesystem is really fragmented...\n");
+		status = -EAGAIN;
+		reason = RESTART_META;
+		goto leave;
+	}
+
+	status = ocfs2_claim_clusters(osb, handle, data_ac, 1,
+				      &bit_off, &num_bits);
+	if (status < 0) {
+		if (status != -ENOSPC)
+			mlog_errno(status);
+		goto leave;
+	}
+
+	BUG_ON(num_bits > clusters_to_add);
+
+	/* reserve our write early -- insert_extent may update the inode */
+	status = ocfs2_journal_access(handle, inode, fe_bh,
+				      OCFS2_JOURNAL_ACCESS_WRITE);
+	if (status < 0) {
+		mlog_errno(status);
+		goto leave;
+	}
+
+	block = ocfs2_clusters_to_blocks(osb->sb, bit_off);
+	mlog(0, "Allocating %u clusters at block %u for inode %"MLFu64"\n",
+	     num_bits, bit_off, OCFS2_I(inode)->ip_blkno);
+	status = ocfs2_insert_extent(osb, handle, inode, fe_bh, block,
+				     num_bits, meta_ac);
+	if (status < 0) {
+		mlog_errno(status);
+		goto leave;
+	}
+
+	le32_add_cpu(&fe->i_clusters, num_bits);
+	spin_lock(&OCFS2_I(inode)->ip_lock);
+	OCFS2_I(inode)->ip_clusters = le32_to_cpu(fe->i_clusters);
+	spin_unlock(&OCFS2_I(inode)->ip_lock);
+
+	status = ocfs2_journal_dirty(handle, fe_bh);
+	if (status < 0) {
+		mlog_errno(status);
+		goto leave;
+	}
+
+	clusters_to_add -= num_bits;
+
+	if (clusters_to_add) {
+		mlog(0, "need to alloc once more, clusters = %u, wanted = "
+		     "%u\n", fe->i_clusters, clusters_to_add);
+		status = -EAGAIN;
+		reason = RESTART_TRANS;
+	}
+
+leave:
+	mlog_exit(status);
+	if (reason_ret)
+		*reason_ret = reason;
+	return status;
+}
+
+static int ocfs2_extend_allocation(struct inode *inode,
+				   u32 clusters_to_add)
+{
+	int status = 0;
+	int restart_func = 0;
+	int drop_alloc_sem = 0;
+	int credits, num_free_extents;
+	u32 prev_clusters;
+	struct buffer_head *bh = NULL;
+	struct ocfs2_dinode *fe = NULL;
+	struct ocfs2_journal_handle *handle = NULL;
+	struct ocfs2_alloc_context *data_ac = NULL;
+	struct ocfs2_alloc_context *meta_ac = NULL;
+	enum ocfs2_alloc_restarted why;
+	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+
+	mlog_entry("(clusters_to_add = %u)\n", clusters_to_add);
+
+	status = ocfs2_read_block(osb, OCFS2_I(inode)->ip_blkno, &bh,
+				  OCFS2_BH_CACHED, inode);
+	if (status < 0) {
+		mlog_errno(status);
+		goto leave;
+	}
+
+	fe = (struct ocfs2_dinode *) bh->b_data;
+	if (!OCFS2_IS_VALID_DINODE(fe)) {
+		OCFS2_RO_ON_INVALID_DINODE(inode->i_sb, fe);
+		status = -EIO;
+		goto leave;
+	}
+
+restart_all:
+	BUG_ON(le32_to_cpu(fe->i_clusters) != OCFS2_I(inode)->ip_clusters);
+
+	mlog(0, "extend inode %"MLFu64", i_size = %lld, fe->i_clusters = %u, "
+	     "clusters_to_add = %u\n",
+	     OCFS2_I(inode)->ip_blkno, i_size_read(inode),
+	     fe->i_clusters, clusters_to_add);
+
+	handle = ocfs2_alloc_handle(osb);
+	if (handle == NULL) {
+		status = -ENOMEM;
+		mlog_errno(status);
+		goto leave;
+	}
+
+	num_free_extents = ocfs2_num_free_extents(osb,
+						  inode,
+						  fe);
+	if (num_free_extents < 0) {
+		status = num_free_extents;
+		mlog_errno(status);
+		goto leave;
+	}
+
+	if (!num_free_extents) {
+		status = ocfs2_reserve_new_metadata(osb,
+						    handle,
+						    fe,
+						    &meta_ac);
+		if (status < 0) {
+			if (status != -ENOSPC)
+				mlog_errno(status);
+			goto leave;
+		}
+	}
+
+	status = ocfs2_reserve_clusters(osb,
+					handle,
+					clusters_to_add,
+					&data_ac);
+	if (status < 0) {
+		if (status != -ENOSPC)
+			mlog_errno(status);
+		goto leave;
+	}
+
+	/* blocks peope in read/write from reading our allocation
+	 * until we're done changing it. We depend on i_sem to block
+	 * other extend/truncate calls while we're here. Ordering wrt
+	 * start_trans is important here -- always do it before! */
+	down_write(&OCFS2_I(inode)->ip_alloc_sem);
+	drop_alloc_sem = 1;
+
+	credits = ocfs2_calc_extend_credits(osb->sb, fe, clusters_to_add);
+	handle = ocfs2_start_trans(osb, handle, credits);
+	if (IS_ERR(handle)) {
+		status = PTR_ERR(handle);
+		handle = NULL;
+		mlog_errno(status);
+		goto leave;
+	}
+
+restarted_transaction:
+	/* reserve a write to the file entry early on - that we if we
+	 * run out of credits in the allocation path, we can still
+	 * update i_size. */
+	status = ocfs2_journal_access(handle, inode, bh,
+				      OCFS2_JOURNAL_ACCESS_WRITE);
+	if (status < 0) {
+		mlog_errno(status);
+		goto leave;
+	}
+
+	prev_clusters = OCFS2_I(inode)->ip_clusters;
+
+	status = ocfs2_do_extend_allocation(osb,
+					    inode,
+					    clusters_to_add,
+					    bh,
+					    handle,
+					    data_ac,
+					    meta_ac,
+					    &why);
+	if ((status < 0) && (status != -EAGAIN)) {
+		if (status != -ENOSPC)
+			mlog_errno(status);
+		goto leave;
+	}
+
+	status = ocfs2_journal_dirty(handle, bh);
+	if (status < 0) {
+		mlog_errno(status);
+		goto leave;
+	}
+
+	spin_lock(&OCFS2_I(inode)->ip_lock);
+	clusters_to_add -= (OCFS2_I(inode)->ip_clusters - prev_clusters);
+	spin_unlock(&OCFS2_I(inode)->ip_lock);
+
+	if (why != RESTART_NONE && clusters_to_add) {
+		if (why == RESTART_META) {
+			mlog(0, "restarting function.\n");
+			restart_func = 1;
+		} else {
+			BUG_ON(why != RESTART_TRANS);
+
+			mlog(0, "restarting transaction.\n");
+			/* TODO: This can be more intelligent. */
+			credits = ocfs2_calc_extend_credits(osb->sb,
+							    fe,
+							    clusters_to_add);
+			status = ocfs2_extend_trans(handle, credits);
+			if (status < 0) {
+				/* handle still has to be committed at
+				 * this point. */
+				status = -ENOMEM;
+				mlog_errno(status);
+				goto leave;
+			}
+			goto restarted_transaction;
+		}
+	}
+
+	mlog(0, "fe: i_clusters = %u, i_size=%"MLFu64"\n",
+	     fe->i_clusters, fe->i_size);
+	mlog(0, "inode: ip_clusters=%u, i_size=%lld\n",
+	     OCFS2_I(inode)->ip_clusters, i_size_read(inode));
+
+leave:
+	if (drop_alloc_sem) {
+		up_write(&OCFS2_I(inode)->ip_alloc_sem);
+		drop_alloc_sem = 0;
+	}
+	if (handle) {
+		ocfs2_commit_trans(handle);
+		handle = NULL;
+	}
+	if (data_ac) {
+		ocfs2_free_alloc_context(data_ac);
+		data_ac = NULL;
+	}
+	if (meta_ac) {
+		ocfs2_free_alloc_context(meta_ac);
+		meta_ac = NULL;
+	}
+	if ((!status) && restart_func) {
+		restart_func = 0;
+		goto restart_all;
+	}
+	if (bh) {
+		brelse(bh);
+		bh = NULL;
+	}
+
+	mlog_exit(status);
+	return status;
+}
+
+/* Some parts of this taken from generic_cont_expand, which turned out
+ * to be too fragile to do exactly what we need without us having to
+ * worry about recursive locking in ->commit_write(). */
+static int ocfs2_write_zero_page(struct inode *inode,
+				 u64 size)
+{
+	struct address_space *mapping = inode->i_mapping;
+	struct page *page;
+	unsigned long index;
+	unsigned int offset;
+	struct ocfs2_journal_handle *handle = NULL;
+	int ret;
+
+	offset = (size & (PAGE_CACHE_SIZE-1)); /* Within page */
+	/* ugh.  in prepare/commit_write, if from==to==start of block, we 
+	** skip the prepare.  make sure we never send an offset for the start
+	** of a block
+	*/
+	if ((offset & (inode->i_sb->s_blocksize - 1)) == 0) {
+		offset++;
+	}
+	index = size >> PAGE_CACHE_SHIFT;
+
+	page = grab_cache_page(mapping, index);
+	if (!page) {
+		ret = -ENOMEM;
+		mlog_errno(ret);
+		goto out;
+	}
+
+	ret = ocfs2_prepare_write(NULL, page, offset, offset);
+	if (ret < 0) {
+		mlog_errno(ret);
+		goto out_unlock;
+	}
+
+	if (ocfs2_should_order_data(inode)) {
+		handle = ocfs2_start_walk_page_trans(inode, page, offset,
+						     offset);
+		if (IS_ERR(handle)) {
+			ret = PTR_ERR(handle);
+			handle = NULL;
+			goto out_unlock;
+		}
+	}
+
+	/* must not update i_size! */
+	ret = block_commit_write(page, offset, offset);
+	if (ret < 0)
+		mlog_errno(ret);
+	else
+		ret = 0;
+
+	if (handle)
+		ocfs2_commit_trans(handle);
+out_unlock:
+	unlock_page(page);
+	page_cache_release(page);
+out:
+	return ret;
+}
+
+static int ocfs2_zero_extend(struct inode *inode,
+			     u64 zero_to_size)
+{
+	int ret = 0;
+	u64 start_off;
+	struct super_block *sb = inode->i_sb;
+
+	start_off = ocfs2_align_bytes_to_blocks(sb, i_size_read(inode));
+	while (start_off < zero_to_size) {
+		ret = ocfs2_write_zero_page(inode, start_off);
+		if (ret < 0) {
+			mlog_errno(ret);
+			goto out;
+		}
+
+		start_off += sb->s_blocksize;
+	}
+
+out:
+	return ret;
+}
+
+static int ocfs2_extend_file(struct inode *inode,
+			     struct buffer_head *di_bh,
+			     u64 new_i_size)
+{
+	int ret = 0;
+	u32 clusters_to_add;
+
+	/* setattr sometimes calls us like this. */
+	if (new_i_size == 0)
+		goto out;
+
+	if (i_size_read(inode) == new_i_size)
+  		goto out;
+	BUG_ON(new_i_size < i_size_read(inode));
+
+	clusters_to_add = ocfs2_clusters_for_bytes(inode->i_sb, new_i_size) - 
+		OCFS2_I(inode)->ip_clusters;
+
+	if (clusters_to_add) {
+		ret = ocfs2_extend_allocation(inode, clusters_to_add);
+		if (ret < 0) {
+			mlog_errno(ret);
+			goto out;
+		}
+
+		ret = ocfs2_zero_extend(inode, new_i_size);
+		if (ret < 0) {
+			mlog_errno(ret);
+			goto out;
+		}
+	} 
+
+	/* No allocation required, we just use this helper to
+	 * do a trivial update of i_size. */
+	ret = ocfs2_simple_size_update(inode, di_bh, new_i_size);
+	if (ret < 0) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+out:
+	return ret;
+}
+
+int ocfs2_setattr(struct dentry *dentry, struct iattr *attr)
+{
+	int status = 0, size_change;
+	struct inode *inode = dentry->d_inode;
+	struct super_block *sb = inode->i_sb;
+	struct ocfs2_super *osb = OCFS2_SB(sb);
+	struct buffer_head *bh = NULL;
+	struct ocfs2_journal_handle *handle = NULL;
+
+	mlog_entry("(0x%p, '%.*s')\n", dentry,
+	           dentry->d_name.len, dentry->d_name.name);
+
+	if (attr->ia_valid & ATTR_MODE)
+		mlog(0, "mode change: %d\n", attr->ia_mode);
+	if (attr->ia_valid & ATTR_UID)
+		mlog(0, "uid change: %d\n", attr->ia_uid);
+	if (attr->ia_valid & ATTR_GID)
+		mlog(0, "gid change: %d\n", attr->ia_gid);
+	if (attr->ia_valid & ATTR_SIZE)
+		mlog(0, "size change...\n");
+	if (attr->ia_valid & (ATTR_ATIME | ATTR_MTIME | ATTR_CTIME))
+		mlog(0, "time change...\n");
+
+#define OCFS2_VALID_ATTRS (ATTR_ATIME | ATTR_MTIME | ATTR_CTIME | ATTR_SIZE \
+			   | ATTR_GID | ATTR_UID | ATTR_MODE)
+	if (!(attr->ia_valid & OCFS2_VALID_ATTRS)) {
+		mlog(0, "can't handle attrs: 0x%x\n", attr->ia_valid);
+		return 0;
+	}
+
+	status = inode_change_ok(inode, attr);
+	if (status)
+		return status;
+
+	size_change = S_ISREG(inode->i_mode) && attr->ia_valid & ATTR_SIZE;
+	if (size_change) {
+		status = ocfs2_rw_lock(inode, 1);
+		if (status < 0) {
+			mlog_errno(status);
+			goto bail;
+		}
+	}
+
+	status = ocfs2_meta_lock(inode, NULL, &bh, 1);
+	if (status < 0) {
+		if (status != -ENOENT)
+			mlog_errno(status);
+		goto bail_unlock_rw;
+	}
+
+	if (size_change && attr->ia_size != i_size_read(inode)) {
+		if (i_size_read(inode) > attr->ia_size)
+			status = ocfs2_truncate_file(inode, bh, attr->ia_size);
+		else
+			status = ocfs2_extend_file(inode, bh, attr->ia_size);
+		if (status < 0) {
+			if (status != -ENOSPC)
+				mlog_errno(status);
+			status = -ENOSPC;
+			goto bail_unlock;
+		}
+	}
+
+	handle = ocfs2_start_trans(osb, NULL, OCFS2_INODE_UPDATE_CREDITS);
+	if (IS_ERR(handle)) {
+		status = PTR_ERR(handle);
+		mlog_errno(status);
+		goto bail_unlock;
+	}
+
+	status = inode_setattr(inode, attr);
+	if (status < 0) {
+		mlog_errno(status);
+		goto bail_commit;
+	}
+
+	status = ocfs2_mark_inode_dirty(handle, inode, bh);
+	if (status < 0)
+		mlog_errno(status);
+
+bail_commit:
+	ocfs2_commit_trans(handle);
+bail_unlock:
+	ocfs2_meta_unlock(inode, 1);
+bail_unlock_rw:
+	if (size_change)
+		ocfs2_rw_unlock(inode, 1);
+bail:
+	if (bh)
+		brelse(bh);
+
+	mlog_exit(status);
+	return status;
+}
+
+int ocfs2_getattr(struct vfsmount *mnt,
+		  struct dentry *dentry,
+		  struct kstat *stat)
+{
+	struct inode *inode = dentry->d_inode;
+	struct super_block *sb = dentry->d_inode->i_sb;
+	struct ocfs2_super *osb = sb->s_fs_info;
+	int err;
+
+	mlog_entry_void();
+
+	err = ocfs2_inode_revalidate(dentry);
+	if (err) {
+		if (err != -ENOENT)
+			mlog_errno(err);
+		goto bail;
+	}
+
+	generic_fillattr(inode, stat);
+
+	/* We set the blksize from the cluster size for performance */
+	stat->blksize = osb->s_clustersize;
+
+bail:
+	mlog_exit(err);
+
+	return err;
+}
+
+static int ocfs2_write_remove_suid(struct inode *inode)
+{
+	int ret;
+	struct buffer_head *bh = NULL;
+	struct ocfs2_inode_info *oi = OCFS2_I(inode);
+	struct ocfs2_journal_handle *handle;
+	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+	struct ocfs2_dinode *di;
+
+	mlog_entry("(Inode %"MLFu64", mode 0%o)\n", oi->ip_blkno,
+		   inode->i_mode);
+
+	handle = ocfs2_start_trans(osb, NULL, OCFS2_INODE_UPDATE_CREDITS);
+	if (handle == NULL) {
+		ret = -ENOMEM;
+		mlog_errno(ret);
+		goto out;
+	}
+
+	ret = ocfs2_read_block(osb, oi->ip_blkno, &bh, OCFS2_BH_CACHED, inode);
+	if (ret < 0) {
+		mlog_errno(ret);
+		goto out_trans;
+	}
+
+	ret = ocfs2_journal_access(handle, inode, bh,
+				   OCFS2_JOURNAL_ACCESS_WRITE);
+	if (ret < 0) {
+		mlog_errno(ret);
+		goto out_bh;
+	}
+
+	inode->i_mode &= ~S_ISUID;
+	if ((inode->i_mode & S_ISGID) && (inode->i_mode & S_IXGRP))
+		inode->i_mode &= ~S_ISGID;
+
+	di = (struct ocfs2_dinode *) bh->b_data;
+	di->i_mode = cpu_to_le16(inode->i_mode);
+
+	ret = ocfs2_journal_dirty(handle, bh);
+	if (ret < 0)
+		mlog_errno(ret);
+out_bh:
+	brelse(bh);
+out_trans:
+	ocfs2_commit_trans(handle);
+out:
+	mlog_exit(ret);
+	return ret;
+}
+
+static inline int ocfs2_write_should_remove_suid(struct inode *inode)
+{
+	mode_t mode = inode->i_mode;
+
+	if (!capable(CAP_FSETID)) {
+		if (unlikely(mode & S_ISUID))
+			return 1;
+
+		if (unlikely((mode & S_ISGID) && (mode & S_IXGRP)))
+			return 1;
+	}
+	return 0;
+}
+
+static ssize_t ocfs2_file_aio_write(struct kiocb *iocb,
+				    const char __user *buf,
+				    size_t count,
+				    loff_t pos)
+{
+	struct iovec local_iov = { .iov_base = (void __user *)buf,
+				   .iov_len = count };
+	int ret, rw_level = -1, meta_level = -1, have_alloc_sem = 0;
+	u32 clusters;
+	struct file *filp = iocb->ki_filp;
+	struct inode *inode = filp->f_dentry->d_inode;
+	loff_t newsize, saved_pos;
+#ifdef OCFS2_ORACORE_WORKAROUNDS
+	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+#endif
+
+	mlog_entry("(0x%p, 0x%p, %u, '%.*s')\n", filp, buf,
+		   (unsigned int)count,
+		   filp->f_dentry->d_name.len,
+		   filp->f_dentry->d_name.name);
+
+	/* happy write of zero bytes */
+	if (count == 0)
+		return 0;
+
+	if (!inode) {
+		mlog(0, "bad inode\n");
+		return -EIO;
+	}
+
+#ifdef OCFS2_ORACORE_WORKAROUNDS
+	/* ugh, work around some applications which open everything O_DIRECT +
+	 * O_APPEND and really don't mean to use O_DIRECT. */
+	if (osb->s_mount_opt & OCFS2_MOUNT_COMPAT_OCFS &&
+	    (filp->f_flags & O_APPEND) && (filp->f_flags & O_DIRECT)) 
+		filp->f_flags &= ~O_DIRECT;
+#endif
+
+	down(&inode->i_sem);
+	/* to match setattr's i_sem -> i_alloc_sem -> rw_lock ordering */
+	if (filp->f_flags & O_DIRECT) {
+		have_alloc_sem = 1;
+		down_read(&inode->i_alloc_sem);
+	}
+
+	/* concurrent O_DIRECT writes are allowed */
+	rw_level = (filp->f_flags & O_DIRECT) ? 0 : 1;
+	ret = ocfs2_rw_lock(inode, rw_level);
+	if (ret < 0) {
+		rw_level = -1;
+		mlog_errno(ret);
+		goto out;
+	}
+
+	/* 
+	 * We sample i_size under a read level meta lock to see if our write
+	 * is extending the file, if it is we back off and get a write level
+	 * meta lock.
+	 */
+	meta_level = (filp->f_flags & O_APPEND) ? 1 : 0;
+	for(;;) {
+		ret = ocfs2_meta_lock(inode, NULL, NULL, meta_level);
+		if (ret < 0) {
+			meta_level = -1;
+			mlog_errno(ret);
+			goto out;
+		}
+
+		/* Clear suid / sgid if necessary. We do this here
+		 * instead of later in the write path because
+		 * remove_suid() calls ->setattr without any hint that
+		 * we may have already done our cluster locking. Since
+		 * ocfs2_setattr() *must* take cluster locks to
+		 * proceeed, this will lead us to recursively lock the
+		 * inode. There's also the dinode i_size state which
+		 * can be lost via setattr during extending writes (we
+		 * set inode->i_size at the end of a write. */
+		if (ocfs2_write_should_remove_suid(inode)) {
+			if (meta_level == 0) {
+				ocfs2_meta_unlock(inode, meta_level);
+				meta_level = 1;
+				continue;
+			}
+
+			ret = ocfs2_write_remove_suid(inode);
+			if (ret < 0) {
+				mlog_errno(ret);
+				goto out;
+			}
+		}
+
+		/* work on a copy of ppos until we're sure that we won't have
+		 * to recalculate it due to relocking. */
+		if (filp->f_flags & O_APPEND) {
+			saved_pos = i_size_read(inode);
+			mlog(0, "O_APPEND: inode->i_size=%llu\n", saved_pos);
+		} else {
+			saved_pos = iocb->ki_pos;
+		}
+		newsize = count + saved_pos;
+
+		mlog(0, "pos=%lld newsize=%"MLFu64" cursize=%lld\n",
+		     saved_pos, newsize, i_size_read(inode));
+
+		/* No need for a higher level metadata lock if we're
+		 * never going past i_size. */
+		if (newsize <= i_size_read(inode))
+			break;
+
+		if (meta_level == 0) {
+			ocfs2_meta_unlock(inode, meta_level);
+			meta_level = 1;
+			continue;
+		}
+
+		spin_lock(&OCFS2_I(inode)->ip_lock);
+		clusters = ocfs2_clusters_for_bytes(inode->i_sb, newsize) -
+			OCFS2_I(inode)->ip_clusters;
+		spin_unlock(&OCFS2_I(inode)->ip_lock);
+
+		mlog(0, "Writing at EOF, may need more allocation: "
+		     "i_size = %lld, newsize = %"MLFu64", need %u clusters\n",
+		     i_size_read(inode), newsize, clusters);
+
+		/* We only want to continue the rest of this loop if
+		 * our extend will actually require more
+		 * allocation. */
+		if (!clusters)
+			break;
+
+		ret = ocfs2_extend_allocation(inode, clusters);
+		if (ret < 0) {
+			if (ret != -ENOSPC)
+				mlog_errno(ret);
+			goto out;
+		}
+
+		/* Fill any holes which would've been created by this
+		 * write. If we're O_APPEND, this will wind up
+		 * (correctly) being a noop. */
+		ret = ocfs2_zero_extend(inode, (u64) newsize - count);
+		if (ret < 0) {
+			mlog_errno(ret);
+			goto out;
+		}
+		break;
+	}
+
+	/* ok, we're done with i_size and alloc work */
+	iocb->ki_pos = saved_pos;
+	ocfs2_meta_unlock(inode, meta_level);
+	meta_level = -1;
+
+	/* communicate with ocfs2_dio_end_io */
+	ocfs2_iocb_set_rw_locked(iocb);
+
+#ifdef OCFS2_ORACORE_WORKAROUNDS
+	if (osb->s_mount_opt & OCFS2_MOUNT_COMPAT_OCFS &&
+	    filp->f_flags & O_DIRECT) {
+		unsigned int saved_flags = filp->f_flags;
+		int sector_size = 1 << osb->s_sectsize_bits;
+
+		if ((saved_pos & (sector_size - 1)) ||
+		    (count & (sector_size - 1)) ||
+		    ((unsigned long)buf & (sector_size - 1))) {
+			filp->f_flags |= O_SYNC;
+			filp->f_flags &= ~O_DIRECT;
+		}
+
+		ret = generic_file_aio_write_nolock(iocb, &local_iov, 1,
+						    &iocb->ki_pos);
+
+		filp->f_flags = saved_flags;
+	} else
+#endif
+		ret = generic_file_aio_write_nolock(iocb, &local_iov, 1,
+						    &iocb->ki_pos);
+
+	/* buffered aio wouldn't have proper lock coverage today */
+	BUG_ON(ret == -EIOCBQUEUED && !(filp->f_flags & O_DIRECT));
+
+	/* 
+	 * deep in g_f_a_w_n()->ocfs2_direct_IO we pass in a ocfs2_dio_end_io
+	 * function pointer which is called when o_direct io completes so that
+	 * it can unlock our rw lock.  (it's the clustered equivalent of
+	 * i_alloc_sem; protects truncate from racing with pending ios).
+	 * Unfortunately there are error cases which call end_io and others
+	 * that don't.  so we don't have to unlock the rw_lock if either an
+	 * async dio is going to do it in the future or an end_io after an
+	 * error has already done it.
+	 */
+	if (ret == -EIOCBQUEUED || !ocfs2_iocb_is_rw_locked(iocb)) {
+		rw_level = -1;
+		have_alloc_sem = 0;
+	}
+
+out:
+	if (meta_level != -1)
+		ocfs2_meta_unlock(inode, meta_level);
+	if (have_alloc_sem)
+		up_read(&inode->i_alloc_sem);
+	if (rw_level != -1) 
+		ocfs2_rw_unlock(inode, rw_level);
+	up(&inode->i_sem);
+
+	mlog_exit(ret);
+	return ret;
+}
+
+static ssize_t ocfs2_file_aio_read(struct kiocb *iocb,
+				   char __user *buf,
+				   size_t count,
+				   loff_t pos)
+{
+	int ret = 0, rw_level = -1, have_alloc_sem = 0;
+	struct file *filp = iocb->ki_filp;
+	struct inode *inode = filp->f_dentry->d_inode;
+#ifdef OCFS2_ORACORE_WORKAROUNDS
+	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+#endif
+
+	mlog_entry("(0x%p, 0x%p, %u, '%.*s')\n", filp, buf,
+		   (unsigned int)count,
+		   filp->f_dentry->d_name.len,
+		   filp->f_dentry->d_name.name);
+
+	if (!inode) {
+		ret = -EINVAL;
+		mlog_errno(ret);
+		goto bail;
+	}
+
+#ifdef OCFS2_ORACORE_WORKAROUNDS
+	if (osb->s_mount_opt & OCFS2_MOUNT_COMPAT_OCFS) {
+		if (filp->f_flags & O_DIRECT) {
+			int sector_size = 1 << osb->s_sectsize_bits;
+
+			if ((pos & (sector_size - 1)) ||
+			    (count & (sector_size - 1)) ||
+			    ((unsigned long)buf & (sector_size - 1)) ||
+			    (i_size_read(inode) & (sector_size -1))) {
+				filp->f_flags &= ~O_DIRECT;
+			}
+		}
+	}
+#endif
+
+	/* 
+	 * buffered reads protect themselves in ->readpage().  O_DIRECT reads
+	 * need locks to protect pending reads from racing with truncate.
+	 */
+	if (filp->f_flags & O_DIRECT) {
+		down_read(&inode->i_alloc_sem);
+		have_alloc_sem = 1;
+
+		ret = ocfs2_rw_lock(inode, 0);
+		if (ret < 0) {
+			mlog_errno(ret);
+			goto bail;
+		}
+		rw_level = 0;
+		/* communicate with ocfs2_dio_end_io */
+		ocfs2_iocb_set_rw_locked(iocb);
+	}
+
+	ret = generic_file_aio_read(iocb, buf, count, iocb->ki_pos);
+	if (ret == -EINVAL)
+		mlog(ML_ERROR, "generic_file_aio_read returned -EINVAL\n");
+
+	/* buffered aio wouldn't have proper lock coverage today */
+	BUG_ON(ret == -EIOCBQUEUED && !(filp->f_flags & O_DIRECT));
+
+	/* see ocfs2_file_aio_write */
+	if (ret == -EIOCBQUEUED || !ocfs2_iocb_is_rw_locked(iocb)) {
+		rw_level = -1;
+		have_alloc_sem = 0;
+	}
+
+bail:
+	if (have_alloc_sem)
+		up_read(&inode->i_alloc_sem);
+	if (rw_level != -1) 
+		ocfs2_rw_unlock(inode, rw_level);
+	mlog_exit(ret);
+
+	return ret;
+}
+
+struct inode_operations ocfs2_file_iops = {
+	.setattr	= ocfs2_setattr,
+	.getattr	= ocfs2_getattr,
+};
+
+struct inode_operations ocfs2_special_file_iops = {
+	.setattr	= ocfs2_setattr,
+	.getattr	= ocfs2_getattr,
+};
+
+struct file_operations ocfs2_fops = {
+	.read		= do_sync_read,
+	.write		= do_sync_write,
+	.sendfile	= generic_file_sendfile,
+	.mmap		= ocfs2_mmap,
+	.fsync		= ocfs2_sync_file,
+	.release	= ocfs2_file_release,
+	.open		= ocfs2_file_open,
+	.aio_read	= ocfs2_file_aio_read,
+	.aio_write	= ocfs2_file_aio_write,
+};
+
+struct file_operations ocfs2_dops = {
+	.read		= generic_read_dir,
+	.readdir	= ocfs2_readdir,
+	.fsync		= ocfs2_sync_file,
+};