ocfs2: Add extent tree operation for xattr value btrees

Add some thin wrappers around ocfs2_insert_extent() for each of the 3
different btree types, ocfs2_inode_insert_extent(),
ocfs2_xattr_value_insert_extent() and ocfs2_xattr_tree_insert_extent(). The
last is for the xattr index btree, which will be used in a followup patch.

All the old callers in file.c etc will call ocfs2_dinode_insert_extent(),
while the other two handle the xattr issue. And the init of extent tree are
handled by these functions.

When storing xattr value which is too large, we will allocate some clusters
for it and here ocfs2_extent_list and ocfs2_extent_rec will also be used. In
order to re-use the b-tree operation code, a new parameter named "private"
is added into ocfs2_extent_tree and it is used to indicate the root of
ocfs2_exent_list. The reason is that we can't deduce the root from the
buffer_head now. It may be in an inode, an ocfs2_xattr_block or even worse,
in any place in an ocfs2_xattr_bucket.

Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

1 files changed, 305 insertions, 0 deletions

diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c
new file mode 100644
index 0000000..9604a4c
--- /dev/null
+++ b/fs/ocfs2/xattr.c
@@ -0,0 +1,305 @@
+/* -*- mode: c; c-basic-offset: 8; -*-
+ * vim: noexpandtab sw=8 ts=8 sts=0:
+ *
+ * xattr.c
+ *
+ * Copyright (C) 2008 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.
+ */
+
+#define MLOG_MASK_PREFIX ML_XATTR
+#include <cluster/masklog.h>
+
+#include "ocfs2.h"
+#include "alloc.h"
+#include "dlmglue.h"
+#include "file.h"
+#include "inode.h"
+#include "journal.h"
+#include "ocfs2_fs.h"
+#include "suballoc.h"
+#include "uptodate.h"
+#include "buffer_head_io.h"
+
+static int ocfs2_xattr_extend_allocation(struct inode *inode,
+					 u32 clusters_to_add,
+					 struct buffer_head *xattr_bh,
+					 struct ocfs2_xattr_value_root *xv)
+{
+	int status = 0;
+	int restart_func = 0;
+	int credits = 0;
+	handle_t *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);
+	struct ocfs2_extent_list *root_el = &xv->xr_list;
+	u32 prev_clusters, logical_start = le32_to_cpu(xv->xr_clusters);
+
+	mlog(0, "(clusters_to_add for xattr= %u)\n", clusters_to_add);
+
+restart_all:
+
+	status = ocfs2_lock_allocators(inode, xattr_bh, root_el,
+				       clusters_to_add, 0, &data_ac,
+				       &meta_ac, OCFS2_XATTR_VALUE_EXTENT, xv);
+	if (status) {
+		mlog_errno(status);
+		goto leave;
+	}
+
+	credits = ocfs2_calc_extend_credits(osb->sb, root_el, clusters_to_add);
+	handle = ocfs2_start_trans(osb, credits);
+	if (IS_ERR(handle)) {
+		status = PTR_ERR(handle);
+		handle = NULL;
+		mlog_errno(status);
+		goto leave;
+	}
+
+restarted_transaction:
+	status = ocfs2_journal_access(handle, inode, xattr_bh,
+				      OCFS2_JOURNAL_ACCESS_WRITE);
+	if (status < 0) {
+		mlog_errno(status);
+		goto leave;
+	}
+
+	prev_clusters = le32_to_cpu(xv->xr_clusters);
+	status = ocfs2_add_clusters_in_btree(osb,
+					     inode,
+					     &logical_start,
+					     clusters_to_add,
+					     0,
+					     xattr_bh,
+					     root_el,
+					     handle,
+					     data_ac,
+					     meta_ac,
+					     &why,
+					     OCFS2_XATTR_VALUE_EXTENT,
+					     xv);
+	if ((status < 0) && (status != -EAGAIN)) {
+		if (status != -ENOSPC)
+			mlog_errno(status);
+		goto leave;
+	}
+
+	status = ocfs2_journal_dirty(handle, xattr_bh);
+	if (status < 0) {
+		mlog_errno(status);
+		goto leave;
+	}
+
+	clusters_to_add -= le32_to_cpu(xv->xr_clusters) - prev_clusters;
+
+	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,
+							    root_el,
+							    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;
+		}
+	}
+
+leave:
+	if (handle) {
+		ocfs2_commit_trans(osb, 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;
+	}
+
+	return status;
+}
+
+static int __ocfs2_remove_xattr_range(struct inode *inode,
+				      struct buffer_head *root_bh,
+				      struct ocfs2_xattr_value_root *xv,
+				      u32 cpos, u32 phys_cpos, u32 len,
+				      struct ocfs2_cached_dealloc_ctxt *dealloc)
+{
+	int ret;
+	u64 phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
+	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+	struct inode *tl_inode = osb->osb_tl_inode;
+	handle_t *handle;
+	struct ocfs2_alloc_context *meta_ac = NULL;
+
+	ret = ocfs2_lock_allocators(inode, root_bh, &xv->xr_list,
+				    0, 1, NULL, &meta_ac,
+				    OCFS2_XATTR_VALUE_EXTENT, xv);
+	if (ret) {
+		mlog_errno(ret);
+		return ret;
+	}
+
+	mutex_lock(&tl_inode->i_mutex);
+
+	if (ocfs2_truncate_log_needs_flush(osb)) {
+		ret = __ocfs2_flush_truncate_log(osb);
+		if (ret < 0) {
+			mlog_errno(ret);
+			goto out;
+		}
+	}
+
+	handle = ocfs2_start_trans(osb, OCFS2_REMOVE_EXTENT_CREDITS);
+	if (IS_ERR(handle)) {
+		ret = PTR_ERR(handle);
+		mlog_errno(ret);
+		goto out;
+	}
+
+	ret = ocfs2_journal_access(handle, inode, root_bh,
+				   OCFS2_JOURNAL_ACCESS_WRITE);
+	if (ret) {
+		mlog_errno(ret);
+		goto out_commit;
+	}
+
+	ret = ocfs2_remove_extent(inode, root_bh, cpos, len, handle, meta_ac,
+				  dealloc, OCFS2_XATTR_VALUE_EXTENT, xv);
+	if (ret) {
+		mlog_errno(ret);
+		goto out_commit;
+	}
+
+	le32_add_cpu(&xv->xr_clusters, -len);
+
+	ret = ocfs2_journal_dirty(handle, root_bh);
+	if (ret) {
+		mlog_errno(ret);
+		goto out_commit;
+	}
+
+	ret = ocfs2_truncate_log_append(osb, handle, phys_blkno, len);
+	if (ret)
+		mlog_errno(ret);
+
+out_commit:
+	ocfs2_commit_trans(osb, handle);
+out:
+	mutex_unlock(&tl_inode->i_mutex);
+
+	if (meta_ac)
+		ocfs2_free_alloc_context(meta_ac);
+
+	return ret;
+}
+
+static int ocfs2_xattr_shrink_size(struct inode *inode,
+				   u32 old_clusters,
+				   u32 new_clusters,
+				   struct buffer_head *root_bh,
+				   struct ocfs2_xattr_value_root *xv)
+{
+	int ret = 0;
+	u32 trunc_len, cpos, phys_cpos, alloc_size;
+	u64 block;
+	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+	struct ocfs2_cached_dealloc_ctxt dealloc;
+
+	ocfs2_init_dealloc_ctxt(&dealloc);
+
+	if (old_clusters <= new_clusters)
+		return 0;
+
+	cpos = new_clusters;
+	trunc_len = old_clusters - new_clusters;
+	while (trunc_len) {
+		ret = ocfs2_xattr_get_clusters(inode, cpos, &phys_cpos,
+					       &alloc_size, &xv->xr_list);
+		if (ret) {
+			mlog_errno(ret);
+			goto out;
+		}
+
+		if (alloc_size > trunc_len)
+			alloc_size = trunc_len;
+
+		ret = __ocfs2_remove_xattr_range(inode, root_bh, xv, cpos,
+						 phys_cpos, alloc_size,
+						 &dealloc);
+		if (ret) {
+			mlog_errno(ret);
+			goto out;
+		}
+
+		block = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
+		ocfs2_remove_xattr_clusters_from_cache(inode, block,
+						       alloc_size);
+		cpos += alloc_size;
+		trunc_len -= alloc_size;
+	}
+
+out:
+	ocfs2_schedule_truncate_log_flush(osb, 1);
+	ocfs2_run_deallocs(osb, &dealloc);
+
+	return ret;
+}
+
+static int ocfs2_xattr_value_truncate(struct inode *inode,
+				      struct buffer_head *root_bh,
+				      struct ocfs2_xattr_value_root *xv,
+				      int len)
+{
+	int ret;
+	u32 new_clusters = ocfs2_clusters_for_bytes(inode->i_sb, len);
+	u32 old_clusters = le32_to_cpu(xv->xr_clusters);
+
+	if (new_clusters == old_clusters)
+		return 0;
+
+	if (new_clusters > old_clusters)
+		ret = ocfs2_xattr_extend_allocation(inode,
+						    new_clusters - old_clusters,
+						    root_bh, xv);
+	else
+		ret = ocfs2_xattr_shrink_size(inode,
+					      old_clusters, new_clusters,
+					      root_bh, xv);
+
+	return ret;
+}