v4.19.13 snapshot.
diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c
new file mode 100644
index 0000000..7a5ee14
--- /dev/null
+++ b/fs/ocfs2/refcounttree.c
@@ -0,0 +1,4899 @@
+/* -*- mode: c; c-basic-offset: 8; -*-
+ * vim: noexpandtab sw=8 ts=8 sts=0:
+ *
+ * refcounttree.c
+ *
+ * Copyright (C) 2009 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 version 2 as published by the Free Software Foundation.
+ *
+ * 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.
+ */
+
+#include <linux/sort.h>
+#include <cluster/masklog.h>
+#include "ocfs2.h"
+#include "inode.h"
+#include "alloc.h"
+#include "suballoc.h"
+#include "journal.h"
+#include "uptodate.h"
+#include "super.h"
+#include "buffer_head_io.h"
+#include "blockcheck.h"
+#include "refcounttree.h"
+#include "sysfile.h"
+#include "dlmglue.h"
+#include "extent_map.h"
+#include "aops.h"
+#include "xattr.h"
+#include "namei.h"
+#include "ocfs2_trace.h"
+#include "file.h"
+
+#include <linux/bio.h>
+#include <linux/blkdev.h>
+#include <linux/slab.h>
+#include <linux/writeback.h>
+#include <linux/pagevec.h>
+#include <linux/swap.h>
+#include <linux/security.h>
+#include <linux/fsnotify.h>
+#include <linux/quotaops.h>
+#include <linux/namei.h>
+#include <linux/mount.h>
+#include <linux/posix_acl.h>
+
+struct ocfs2_cow_context {
+ struct inode *inode;
+ u32 cow_start;
+ u32 cow_len;
+ struct ocfs2_extent_tree data_et;
+ struct ocfs2_refcount_tree *ref_tree;
+ struct buffer_head *ref_root_bh;
+ struct ocfs2_alloc_context *meta_ac;
+ struct ocfs2_alloc_context *data_ac;
+ struct ocfs2_cached_dealloc_ctxt dealloc;
+ void *cow_object;
+ struct ocfs2_post_refcount *post_refcount;
+ int extra_credits;
+ int (*get_clusters)(struct ocfs2_cow_context *context,
+ u32 v_cluster, u32 *p_cluster,
+ u32 *num_clusters,
+ unsigned int *extent_flags);
+ int (*cow_duplicate_clusters)(handle_t *handle,
+ struct inode *inode,
+ u32 cpos, u32 old_cluster,
+ u32 new_cluster, u32 new_len);
+};
+
+static inline struct ocfs2_refcount_tree *
+cache_info_to_refcount(struct ocfs2_caching_info *ci)
+{
+ return container_of(ci, struct ocfs2_refcount_tree, rf_ci);
+}
+
+static int ocfs2_validate_refcount_block(struct super_block *sb,
+ struct buffer_head *bh)
+{
+ int rc;
+ struct ocfs2_refcount_block *rb =
+ (struct ocfs2_refcount_block *)bh->b_data;
+
+ trace_ocfs2_validate_refcount_block((unsigned long long)bh->b_blocknr);
+
+ BUG_ON(!buffer_uptodate(bh));
+
+ /*
+ * If the ecc fails, we return the error but otherwise
+ * leave the filesystem running. We know any error is
+ * local to this block.
+ */
+ rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &rb->rf_check);
+ if (rc) {
+ mlog(ML_ERROR, "Checksum failed for refcount block %llu\n",
+ (unsigned long long)bh->b_blocknr);
+ return rc;
+ }
+
+
+ if (!OCFS2_IS_VALID_REFCOUNT_BLOCK(rb)) {
+ rc = ocfs2_error(sb,
+ "Refcount block #%llu has bad signature %.*s\n",
+ (unsigned long long)bh->b_blocknr, 7,
+ rb->rf_signature);
+ goto out;
+ }
+
+ if (le64_to_cpu(rb->rf_blkno) != bh->b_blocknr) {
+ rc = ocfs2_error(sb,
+ "Refcount block #%llu has an invalid rf_blkno of %llu\n",
+ (unsigned long long)bh->b_blocknr,
+ (unsigned long long)le64_to_cpu(rb->rf_blkno));
+ goto out;
+ }
+
+ if (le32_to_cpu(rb->rf_fs_generation) != OCFS2_SB(sb)->fs_generation) {
+ rc = ocfs2_error(sb,
+ "Refcount block #%llu has an invalid rf_fs_generation of #%u\n",
+ (unsigned long long)bh->b_blocknr,
+ le32_to_cpu(rb->rf_fs_generation));
+ goto out;
+ }
+out:
+ return rc;
+}
+
+static int ocfs2_read_refcount_block(struct ocfs2_caching_info *ci,
+ u64 rb_blkno,
+ struct buffer_head **bh)
+{
+ int rc;
+ struct buffer_head *tmp = *bh;
+
+ rc = ocfs2_read_block(ci, rb_blkno, &tmp,
+ ocfs2_validate_refcount_block);
+
+ /* If ocfs2_read_block() got us a new bh, pass it up. */
+ if (!rc && !*bh)
+ *bh = tmp;
+
+ return rc;
+}
+
+static u64 ocfs2_refcount_cache_owner(struct ocfs2_caching_info *ci)
+{
+ struct ocfs2_refcount_tree *rf = cache_info_to_refcount(ci);
+
+ return rf->rf_blkno;
+}
+
+static struct super_block *
+ocfs2_refcount_cache_get_super(struct ocfs2_caching_info *ci)
+{
+ struct ocfs2_refcount_tree *rf = cache_info_to_refcount(ci);
+
+ return rf->rf_sb;
+}
+
+static void ocfs2_refcount_cache_lock(struct ocfs2_caching_info *ci)
+{
+ struct ocfs2_refcount_tree *rf = cache_info_to_refcount(ci);
+
+ spin_lock(&rf->rf_lock);
+}
+
+static void ocfs2_refcount_cache_unlock(struct ocfs2_caching_info *ci)
+{
+ struct ocfs2_refcount_tree *rf = cache_info_to_refcount(ci);
+
+ spin_unlock(&rf->rf_lock);
+}
+
+static void ocfs2_refcount_cache_io_lock(struct ocfs2_caching_info *ci)
+{
+ struct ocfs2_refcount_tree *rf = cache_info_to_refcount(ci);
+
+ mutex_lock(&rf->rf_io_mutex);
+}
+
+static void ocfs2_refcount_cache_io_unlock(struct ocfs2_caching_info *ci)
+{
+ struct ocfs2_refcount_tree *rf = cache_info_to_refcount(ci);
+
+ mutex_unlock(&rf->rf_io_mutex);
+}
+
+static const struct ocfs2_caching_operations ocfs2_refcount_caching_ops = {
+ .co_owner = ocfs2_refcount_cache_owner,
+ .co_get_super = ocfs2_refcount_cache_get_super,
+ .co_cache_lock = ocfs2_refcount_cache_lock,
+ .co_cache_unlock = ocfs2_refcount_cache_unlock,
+ .co_io_lock = ocfs2_refcount_cache_io_lock,
+ .co_io_unlock = ocfs2_refcount_cache_io_unlock,
+};
+
+static struct ocfs2_refcount_tree *
+ocfs2_find_refcount_tree(struct ocfs2_super *osb, u64 blkno)
+{
+ struct rb_node *n = osb->osb_rf_lock_tree.rb_node;
+ struct ocfs2_refcount_tree *tree = NULL;
+
+ while (n) {
+ tree = rb_entry(n, struct ocfs2_refcount_tree, rf_node);
+
+ if (blkno < tree->rf_blkno)
+ n = n->rb_left;
+ else if (blkno > tree->rf_blkno)
+ n = n->rb_right;
+ else
+ return tree;
+ }
+
+ return NULL;
+}
+
+/* osb_lock is already locked. */
+static void ocfs2_insert_refcount_tree(struct ocfs2_super *osb,
+ struct ocfs2_refcount_tree *new)
+{
+ u64 rf_blkno = new->rf_blkno;
+ struct rb_node *parent = NULL;
+ struct rb_node **p = &osb->osb_rf_lock_tree.rb_node;
+ struct ocfs2_refcount_tree *tmp;
+
+ while (*p) {
+ parent = *p;
+
+ tmp = rb_entry(parent, struct ocfs2_refcount_tree,
+ rf_node);
+
+ if (rf_blkno < tmp->rf_blkno)
+ p = &(*p)->rb_left;
+ else if (rf_blkno > tmp->rf_blkno)
+ p = &(*p)->rb_right;
+ else {
+ /* This should never happen! */
+ mlog(ML_ERROR, "Duplicate refcount block %llu found!\n",
+ (unsigned long long)rf_blkno);
+ BUG();
+ }
+ }
+
+ rb_link_node(&new->rf_node, parent, p);
+ rb_insert_color(&new->rf_node, &osb->osb_rf_lock_tree);
+}
+
+static void ocfs2_free_refcount_tree(struct ocfs2_refcount_tree *tree)
+{
+ ocfs2_metadata_cache_exit(&tree->rf_ci);
+ ocfs2_simple_drop_lockres(OCFS2_SB(tree->rf_sb), &tree->rf_lockres);
+ ocfs2_lock_res_free(&tree->rf_lockres);
+ kfree(tree);
+}
+
+static inline void
+ocfs2_erase_refcount_tree_from_list_no_lock(struct ocfs2_super *osb,
+ struct ocfs2_refcount_tree *tree)
+{
+ rb_erase(&tree->rf_node, &osb->osb_rf_lock_tree);
+ if (osb->osb_ref_tree_lru && osb->osb_ref_tree_lru == tree)
+ osb->osb_ref_tree_lru = NULL;
+}
+
+static void ocfs2_erase_refcount_tree_from_list(struct ocfs2_super *osb,
+ struct ocfs2_refcount_tree *tree)
+{
+ spin_lock(&osb->osb_lock);
+ ocfs2_erase_refcount_tree_from_list_no_lock(osb, tree);
+ spin_unlock(&osb->osb_lock);
+}
+
+static void ocfs2_kref_remove_refcount_tree(struct kref *kref)
+{
+ struct ocfs2_refcount_tree *tree =
+ container_of(kref, struct ocfs2_refcount_tree, rf_getcnt);
+
+ ocfs2_free_refcount_tree(tree);
+}
+
+static inline void
+ocfs2_refcount_tree_get(struct ocfs2_refcount_tree *tree)
+{
+ kref_get(&tree->rf_getcnt);
+}
+
+static inline void
+ocfs2_refcount_tree_put(struct ocfs2_refcount_tree *tree)
+{
+ kref_put(&tree->rf_getcnt, ocfs2_kref_remove_refcount_tree);
+}
+
+static inline void ocfs2_init_refcount_tree_ci(struct ocfs2_refcount_tree *new,
+ struct super_block *sb)
+{
+ ocfs2_metadata_cache_init(&new->rf_ci, &ocfs2_refcount_caching_ops);
+ mutex_init(&new->rf_io_mutex);
+ new->rf_sb = sb;
+ spin_lock_init(&new->rf_lock);
+}
+
+static inline void ocfs2_init_refcount_tree_lock(struct ocfs2_super *osb,
+ struct ocfs2_refcount_tree *new,
+ u64 rf_blkno, u32 generation)
+{
+ init_rwsem(&new->rf_sem);
+ ocfs2_refcount_lock_res_init(&new->rf_lockres, osb,
+ rf_blkno, generation);
+}
+
+static struct ocfs2_refcount_tree*
+ocfs2_allocate_refcount_tree(struct ocfs2_super *osb, u64 rf_blkno)
+{
+ struct ocfs2_refcount_tree *new;
+
+ new = kzalloc(sizeof(struct ocfs2_refcount_tree), GFP_NOFS);
+ if (!new)
+ return NULL;
+
+ new->rf_blkno = rf_blkno;
+ kref_init(&new->rf_getcnt);
+ ocfs2_init_refcount_tree_ci(new, osb->sb);
+
+ return new;
+}
+
+static int ocfs2_get_refcount_tree(struct ocfs2_super *osb, u64 rf_blkno,
+ struct ocfs2_refcount_tree **ret_tree)
+{
+ int ret = 0;
+ struct ocfs2_refcount_tree *tree, *new = NULL;
+ struct buffer_head *ref_root_bh = NULL;
+ struct ocfs2_refcount_block *ref_rb;
+
+ spin_lock(&osb->osb_lock);
+ if (osb->osb_ref_tree_lru &&
+ osb->osb_ref_tree_lru->rf_blkno == rf_blkno)
+ tree = osb->osb_ref_tree_lru;
+ else
+ tree = ocfs2_find_refcount_tree(osb, rf_blkno);
+ if (tree)
+ goto out;
+
+ spin_unlock(&osb->osb_lock);
+
+ new = ocfs2_allocate_refcount_tree(osb, rf_blkno);
+ if (!new) {
+ ret = -ENOMEM;
+ mlog_errno(ret);
+ return ret;
+ }
+ /*
+ * We need the generation to create the refcount tree lock and since
+ * it isn't changed during the tree modification, we are safe here to
+ * read without protection.
+ * We also have to purge the cache after we create the lock since the
+ * refcount block may have the stale data. It can only be trusted when
+ * we hold the refcount lock.
+ */
+ ret = ocfs2_read_refcount_block(&new->rf_ci, rf_blkno, &ref_root_bh);
+ if (ret) {
+ mlog_errno(ret);
+ ocfs2_metadata_cache_exit(&new->rf_ci);
+ kfree(new);
+ return ret;
+ }
+
+ ref_rb = (struct ocfs2_refcount_block *)ref_root_bh->b_data;
+ new->rf_generation = le32_to_cpu(ref_rb->rf_generation);
+ ocfs2_init_refcount_tree_lock(osb, new, rf_blkno,
+ new->rf_generation);
+ ocfs2_metadata_cache_purge(&new->rf_ci);
+
+ spin_lock(&osb->osb_lock);
+ tree = ocfs2_find_refcount_tree(osb, rf_blkno);
+ if (tree)
+ goto out;
+
+ ocfs2_insert_refcount_tree(osb, new);
+
+ tree = new;
+ new = NULL;
+
+out:
+ *ret_tree = tree;
+
+ osb->osb_ref_tree_lru = tree;
+
+ spin_unlock(&osb->osb_lock);
+
+ if (new)
+ ocfs2_free_refcount_tree(new);
+
+ brelse(ref_root_bh);
+ return ret;
+}
+
+static int ocfs2_get_refcount_block(struct inode *inode, u64 *ref_blkno)
+{
+ int ret;
+ struct buffer_head *di_bh = NULL;
+ struct ocfs2_dinode *di;
+
+ ret = ocfs2_read_inode_block(inode, &di_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ BUG_ON(!ocfs2_is_refcount_inode(inode));
+
+ di = (struct ocfs2_dinode *)di_bh->b_data;
+ *ref_blkno = le64_to_cpu(di->i_refcount_loc);
+ brelse(di_bh);
+out:
+ return ret;
+}
+
+static int __ocfs2_lock_refcount_tree(struct ocfs2_super *osb,
+ struct ocfs2_refcount_tree *tree, int rw)
+{
+ int ret;
+
+ ret = ocfs2_refcount_lock(tree, rw);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ if (rw)
+ down_write(&tree->rf_sem);
+ else
+ down_read(&tree->rf_sem);
+
+out:
+ return ret;
+}
+
+/*
+ * Lock the refcount tree pointed by ref_blkno and return the tree.
+ * In most case, we lock the tree and read the refcount block.
+ * So read it here if the caller really needs it.
+ *
+ * If the tree has been re-created by other node, it will free the
+ * old one and re-create it.
+ */
+int ocfs2_lock_refcount_tree(struct ocfs2_super *osb,
+ u64 ref_blkno, int rw,
+ struct ocfs2_refcount_tree **ret_tree,
+ struct buffer_head **ref_bh)
+{
+ int ret, delete_tree = 0;
+ struct ocfs2_refcount_tree *tree = NULL;
+ struct buffer_head *ref_root_bh = NULL;
+ struct ocfs2_refcount_block *rb;
+
+again:
+ ret = ocfs2_get_refcount_tree(osb, ref_blkno, &tree);
+ if (ret) {
+ mlog_errno(ret);
+ return ret;
+ }
+
+ ocfs2_refcount_tree_get(tree);
+
+ ret = __ocfs2_lock_refcount_tree(osb, tree, rw);
+ if (ret) {
+ mlog_errno(ret);
+ ocfs2_refcount_tree_put(tree);
+ goto out;
+ }
+
+ ret = ocfs2_read_refcount_block(&tree->rf_ci, tree->rf_blkno,
+ &ref_root_bh);
+ if (ret) {
+ mlog_errno(ret);
+ ocfs2_unlock_refcount_tree(osb, tree, rw);
+ goto out;
+ }
+
+ rb = (struct ocfs2_refcount_block *)ref_root_bh->b_data;
+ /*
+ * If the refcount block has been freed and re-created, we may need
+ * to recreate the refcount tree also.
+ *
+ * Here we just remove the tree from the rb-tree, and the last
+ * kref holder will unlock and delete this refcount_tree.
+ * Then we goto "again" and ocfs2_get_refcount_tree will create
+ * the new refcount tree for us.
+ */
+ if (tree->rf_generation != le32_to_cpu(rb->rf_generation)) {
+ if (!tree->rf_removed) {
+ ocfs2_erase_refcount_tree_from_list(osb, tree);
+ tree->rf_removed = 1;
+ delete_tree = 1;
+ }
+
+ ocfs2_unlock_refcount_tree(osb, tree, rw);
+ /*
+ * We get an extra reference when we create the refcount
+ * tree, so another put will destroy it.
+ */
+ if (delete_tree)
+ ocfs2_refcount_tree_put(tree);
+ brelse(ref_root_bh);
+ ref_root_bh = NULL;
+ goto again;
+ }
+
+ *ret_tree = tree;
+ if (ref_bh) {
+ *ref_bh = ref_root_bh;
+ ref_root_bh = NULL;
+ }
+out:
+ brelse(ref_root_bh);
+ return ret;
+}
+
+void ocfs2_unlock_refcount_tree(struct ocfs2_super *osb,
+ struct ocfs2_refcount_tree *tree, int rw)
+{
+ if (rw)
+ up_write(&tree->rf_sem);
+ else
+ up_read(&tree->rf_sem);
+
+ ocfs2_refcount_unlock(tree, rw);
+ ocfs2_refcount_tree_put(tree);
+}
+
+void ocfs2_purge_refcount_trees(struct ocfs2_super *osb)
+{
+ struct rb_node *node;
+ struct ocfs2_refcount_tree *tree;
+ struct rb_root *root = &osb->osb_rf_lock_tree;
+
+ while ((node = rb_last(root)) != NULL) {
+ tree = rb_entry(node, struct ocfs2_refcount_tree, rf_node);
+
+ trace_ocfs2_purge_refcount_trees(
+ (unsigned long long) tree->rf_blkno);
+
+ rb_erase(&tree->rf_node, root);
+ ocfs2_free_refcount_tree(tree);
+ }
+}
+
+/*
+ * Create a refcount tree for an inode.
+ * We take for granted that the inode is already locked.
+ */
+static int ocfs2_create_refcount_tree(struct inode *inode,
+ struct buffer_head *di_bh)
+{
+ int ret;
+ handle_t *handle = NULL;
+ struct ocfs2_alloc_context *meta_ac = NULL;
+ struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+ struct ocfs2_inode_info *oi = OCFS2_I(inode);
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+ struct buffer_head *new_bh = NULL;
+ struct ocfs2_refcount_block *rb;
+ struct ocfs2_refcount_tree *new_tree = NULL, *tree = NULL;
+ u16 suballoc_bit_start;
+ u32 num_got;
+ u64 suballoc_loc, first_blkno;
+
+ BUG_ON(ocfs2_is_refcount_inode(inode));
+
+ trace_ocfs2_create_refcount_tree(
+ (unsigned long long)oi->ip_blkno);
+
+ ret = ocfs2_reserve_new_metadata_blocks(osb, 1, &meta_ac);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ handle = ocfs2_start_trans(osb, OCFS2_REFCOUNT_TREE_CREATE_CREDITS);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+ ret = ocfs2_claim_metadata(handle, meta_ac, 1, &suballoc_loc,
+ &suballoc_bit_start, &num_got,
+ &first_blkno);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+ new_tree = ocfs2_allocate_refcount_tree(osb, first_blkno);
+ if (!new_tree) {
+ ret = -ENOMEM;
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+ new_bh = sb_getblk(inode->i_sb, first_blkno);
+ if (!new_bh) {
+ ret = -ENOMEM;
+ mlog_errno(ret);
+ goto out_commit;
+ }
+ ocfs2_set_new_buffer_uptodate(&new_tree->rf_ci, new_bh);
+
+ ret = ocfs2_journal_access_rb(handle, &new_tree->rf_ci, new_bh,
+ OCFS2_JOURNAL_ACCESS_CREATE);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+ /* Initialize ocfs2_refcount_block. */
+ rb = (struct ocfs2_refcount_block *)new_bh->b_data;
+ memset(rb, 0, inode->i_sb->s_blocksize);
+ strcpy((void *)rb, OCFS2_REFCOUNT_BLOCK_SIGNATURE);
+ rb->rf_suballoc_slot = cpu_to_le16(meta_ac->ac_alloc_slot);
+ rb->rf_suballoc_loc = cpu_to_le64(suballoc_loc);
+ rb->rf_suballoc_bit = cpu_to_le16(suballoc_bit_start);
+ rb->rf_fs_generation = cpu_to_le32(osb->fs_generation);
+ rb->rf_blkno = cpu_to_le64(first_blkno);
+ rb->rf_count = cpu_to_le32(1);
+ rb->rf_records.rl_count =
+ cpu_to_le16(ocfs2_refcount_recs_per_rb(osb->sb));
+ spin_lock(&osb->osb_lock);
+ rb->rf_generation = osb->s_next_generation++;
+ spin_unlock(&osb->osb_lock);
+
+ ocfs2_journal_dirty(handle, new_bh);
+
+ spin_lock(&oi->ip_lock);
+ oi->ip_dyn_features |= OCFS2_HAS_REFCOUNT_FL;
+ di->i_dyn_features = cpu_to_le16(oi->ip_dyn_features);
+ di->i_refcount_loc = cpu_to_le64(first_blkno);
+ spin_unlock(&oi->ip_lock);
+
+ trace_ocfs2_create_refcount_tree_blkno((unsigned long long)first_blkno);
+
+ ocfs2_journal_dirty(handle, di_bh);
+
+ /*
+ * We have to init the tree lock here since it will use
+ * the generation number to create it.
+ */
+ new_tree->rf_generation = le32_to_cpu(rb->rf_generation);
+ ocfs2_init_refcount_tree_lock(osb, new_tree, first_blkno,
+ new_tree->rf_generation);
+
+ spin_lock(&osb->osb_lock);
+ tree = ocfs2_find_refcount_tree(osb, first_blkno);
+
+ /*
+ * We've just created a new refcount tree in this block. If
+ * we found a refcount tree on the ocfs2_super, it must be
+ * one we just deleted. We free the old tree before
+ * inserting the new tree.
+ */
+ BUG_ON(tree && tree->rf_generation == new_tree->rf_generation);
+ if (tree)
+ ocfs2_erase_refcount_tree_from_list_no_lock(osb, tree);
+ ocfs2_insert_refcount_tree(osb, new_tree);
+ spin_unlock(&osb->osb_lock);
+ new_tree = NULL;
+ if (tree)
+ ocfs2_refcount_tree_put(tree);
+
+out_commit:
+ ocfs2_commit_trans(osb, handle);
+
+out:
+ if (new_tree) {
+ ocfs2_metadata_cache_exit(&new_tree->rf_ci);
+ kfree(new_tree);
+ }
+
+ brelse(new_bh);
+ if (meta_ac)
+ ocfs2_free_alloc_context(meta_ac);
+
+ return ret;
+}
+
+static int ocfs2_set_refcount_tree(struct inode *inode,
+ struct buffer_head *di_bh,
+ u64 refcount_loc)
+{
+ int ret;
+ handle_t *handle = NULL;
+ struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+ struct ocfs2_inode_info *oi = OCFS2_I(inode);
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+ struct buffer_head *ref_root_bh = NULL;
+ struct ocfs2_refcount_block *rb;
+ struct ocfs2_refcount_tree *ref_tree;
+
+ BUG_ON(ocfs2_is_refcount_inode(inode));
+
+ ret = ocfs2_lock_refcount_tree(osb, refcount_loc, 1,
+ &ref_tree, &ref_root_bh);
+ if (ret) {
+ mlog_errno(ret);
+ return ret;
+ }
+
+ handle = ocfs2_start_trans(osb, OCFS2_REFCOUNT_TREE_SET_CREDITS);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+ ret = ocfs2_journal_access_rb(handle, &ref_tree->rf_ci, ref_root_bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+ rb = (struct ocfs2_refcount_block *)ref_root_bh->b_data;
+ le32_add_cpu(&rb->rf_count, 1);
+
+ ocfs2_journal_dirty(handle, ref_root_bh);
+
+ spin_lock(&oi->ip_lock);
+ oi->ip_dyn_features |= OCFS2_HAS_REFCOUNT_FL;
+ di->i_dyn_features = cpu_to_le16(oi->ip_dyn_features);
+ di->i_refcount_loc = cpu_to_le64(refcount_loc);
+ spin_unlock(&oi->ip_lock);
+ ocfs2_journal_dirty(handle, di_bh);
+
+out_commit:
+ ocfs2_commit_trans(osb, handle);
+out:
+ ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
+ brelse(ref_root_bh);
+
+ return ret;
+}
+
+int ocfs2_remove_refcount_tree(struct inode *inode, struct buffer_head *di_bh)
+{
+ int ret, delete_tree = 0;
+ handle_t *handle = NULL;
+ struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+ struct ocfs2_inode_info *oi = OCFS2_I(inode);
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+ struct ocfs2_refcount_block *rb;
+ struct inode *alloc_inode = NULL;
+ struct buffer_head *alloc_bh = NULL;
+ struct buffer_head *blk_bh = NULL;
+ struct ocfs2_refcount_tree *ref_tree;
+ int credits = OCFS2_REFCOUNT_TREE_REMOVE_CREDITS;
+ u64 blk = 0, bg_blkno = 0, ref_blkno = le64_to_cpu(di->i_refcount_loc);
+ u16 bit = 0;
+
+ if (!ocfs2_is_refcount_inode(inode))
+ return 0;
+
+ BUG_ON(!ref_blkno);
+ ret = ocfs2_lock_refcount_tree(osb, ref_blkno, 1, &ref_tree, &blk_bh);
+ if (ret) {
+ mlog_errno(ret);
+ return ret;
+ }
+
+ rb = (struct ocfs2_refcount_block *)blk_bh->b_data;
+
+ /*
+ * If we are the last user, we need to free the block.
+ * So lock the allocator ahead.
+ */
+ if (le32_to_cpu(rb->rf_count) == 1) {
+ blk = le64_to_cpu(rb->rf_blkno);
+ bit = le16_to_cpu(rb->rf_suballoc_bit);
+ if (rb->rf_suballoc_loc)
+ bg_blkno = le64_to_cpu(rb->rf_suballoc_loc);
+ else
+ bg_blkno = ocfs2_which_suballoc_group(blk, bit);
+
+ alloc_inode = ocfs2_get_system_file_inode(osb,
+ EXTENT_ALLOC_SYSTEM_INODE,
+ le16_to_cpu(rb->rf_suballoc_slot));
+ if (!alloc_inode) {
+ ret = -ENOMEM;
+ mlog_errno(ret);
+ goto out;
+ }
+ inode_lock(alloc_inode);
+
+ ret = ocfs2_inode_lock(alloc_inode, &alloc_bh, 1);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_mutex;
+ }
+
+ credits += OCFS2_SUBALLOC_FREE;
+ }
+
+ handle = ocfs2_start_trans(osb, credits);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ mlog_errno(ret);
+ goto out_unlock;
+ }
+
+ ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+ ret = ocfs2_journal_access_rb(handle, &ref_tree->rf_ci, blk_bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+ spin_lock(&oi->ip_lock);
+ oi->ip_dyn_features &= ~OCFS2_HAS_REFCOUNT_FL;
+ di->i_dyn_features = cpu_to_le16(oi->ip_dyn_features);
+ di->i_refcount_loc = 0;
+ spin_unlock(&oi->ip_lock);
+ ocfs2_journal_dirty(handle, di_bh);
+
+ le32_add_cpu(&rb->rf_count , -1);
+ ocfs2_journal_dirty(handle, blk_bh);
+
+ if (!rb->rf_count) {
+ delete_tree = 1;
+ ocfs2_erase_refcount_tree_from_list(osb, ref_tree);
+ ret = ocfs2_free_suballoc_bits(handle, alloc_inode,
+ alloc_bh, bit, bg_blkno, 1);
+ if (ret)
+ mlog_errno(ret);
+ }
+
+out_commit:
+ ocfs2_commit_trans(osb, handle);
+out_unlock:
+ if (alloc_inode) {
+ ocfs2_inode_unlock(alloc_inode, 1);
+ brelse(alloc_bh);
+ }
+out_mutex:
+ if (alloc_inode) {
+ inode_unlock(alloc_inode);
+ iput(alloc_inode);
+ }
+out:
+ ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
+ if (delete_tree)
+ ocfs2_refcount_tree_put(ref_tree);
+ brelse(blk_bh);
+
+ return ret;
+}
+
+static void ocfs2_find_refcount_rec_in_rl(struct ocfs2_caching_info *ci,
+ struct buffer_head *ref_leaf_bh,
+ u64 cpos, unsigned int len,
+ struct ocfs2_refcount_rec *ret_rec,
+ int *index)
+{
+ int i = 0;
+ struct ocfs2_refcount_block *rb =
+ (struct ocfs2_refcount_block *)ref_leaf_bh->b_data;
+ struct ocfs2_refcount_rec *rec = NULL;
+
+ for (; i < le16_to_cpu(rb->rf_records.rl_used); i++) {
+ rec = &rb->rf_records.rl_recs[i];
+
+ if (le64_to_cpu(rec->r_cpos) +
+ le32_to_cpu(rec->r_clusters) <= cpos)
+ continue;
+ else if (le64_to_cpu(rec->r_cpos) > cpos)
+ break;
+
+ /* ok, cpos fail in this rec. Just return. */
+ if (ret_rec)
+ *ret_rec = *rec;
+ goto out;
+ }
+
+ if (ret_rec) {
+ /* We meet with a hole here, so fake the rec. */
+ ret_rec->r_cpos = cpu_to_le64(cpos);
+ ret_rec->r_refcount = 0;
+ if (i < le16_to_cpu(rb->rf_records.rl_used) &&
+ le64_to_cpu(rec->r_cpos) < cpos + len)
+ ret_rec->r_clusters =
+ cpu_to_le32(le64_to_cpu(rec->r_cpos) - cpos);
+ else
+ ret_rec->r_clusters = cpu_to_le32(len);
+ }
+
+out:
+ *index = i;
+}
+
+/*
+ * Try to remove refcount tree. The mechanism is:
+ * 1) Check whether i_clusters == 0, if no, exit.
+ * 2) check whether we have i_xattr_loc in dinode. if yes, exit.
+ * 3) Check whether we have inline xattr stored outside, if yes, exit.
+ * 4) Remove the tree.
+ */
+int ocfs2_try_remove_refcount_tree(struct inode *inode,
+ struct buffer_head *di_bh)
+{
+ int ret;
+ struct ocfs2_inode_info *oi = OCFS2_I(inode);
+ struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+
+ down_write(&oi->ip_xattr_sem);
+ down_write(&oi->ip_alloc_sem);
+
+ if (oi->ip_clusters)
+ goto out;
+
+ if ((oi->ip_dyn_features & OCFS2_HAS_XATTR_FL) && di->i_xattr_loc)
+ goto out;
+
+ if (oi->ip_dyn_features & OCFS2_INLINE_XATTR_FL &&
+ ocfs2_has_inline_xattr_value_outside(inode, di))
+ goto out;
+
+ ret = ocfs2_remove_refcount_tree(inode, di_bh);
+ if (ret)
+ mlog_errno(ret);
+out:
+ up_write(&oi->ip_alloc_sem);
+ up_write(&oi->ip_xattr_sem);
+ return 0;
+}
+
+/*
+ * Find the end range for a leaf refcount block indicated by
+ * el->l_recs[index].e_blkno.
+ */
+static int ocfs2_get_refcount_cpos_end(struct ocfs2_caching_info *ci,
+ struct buffer_head *ref_root_bh,
+ struct ocfs2_extent_block *eb,
+ struct ocfs2_extent_list *el,
+ int index, u32 *cpos_end)
+{
+ int ret, i, subtree_root;
+ u32 cpos;
+ u64 blkno;
+ struct super_block *sb = ocfs2_metadata_cache_get_super(ci);
+ struct ocfs2_path *left_path = NULL, *right_path = NULL;
+ struct ocfs2_extent_tree et;
+ struct ocfs2_extent_list *tmp_el;
+
+ if (index < le16_to_cpu(el->l_next_free_rec) - 1) {
+ /*
+ * We have a extent rec after index, so just use the e_cpos
+ * of the next extent rec.
+ */
+ *cpos_end = le32_to_cpu(el->l_recs[index+1].e_cpos);
+ return 0;
+ }
+
+ if (!eb || (eb && !eb->h_next_leaf_blk)) {
+ /*
+ * We are the last extent rec, so any high cpos should
+ * be stored in this leaf refcount block.
+ */
+ *cpos_end = UINT_MAX;
+ return 0;
+ }
+
+ /*
+ * If the extent block isn't the last one, we have to find
+ * the subtree root between this extent block and the next
+ * leaf extent block and get the corresponding e_cpos from
+ * the subroot. Otherwise we may corrupt the b-tree.
+ */
+ ocfs2_init_refcount_extent_tree(&et, ci, ref_root_bh);
+
+ left_path = ocfs2_new_path_from_et(&et);
+ if (!left_path) {
+ ret = -ENOMEM;
+ mlog_errno(ret);
+ goto out;
+ }
+
+ cpos = le32_to_cpu(eb->h_list.l_recs[index].e_cpos);
+ ret = ocfs2_find_path(ci, left_path, cpos);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ right_path = ocfs2_new_path_from_path(left_path);
+ if (!right_path) {
+ ret = -ENOMEM;
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_find_cpos_for_right_leaf(sb, left_path, &cpos);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_find_path(ci, right_path, cpos);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ subtree_root = ocfs2_find_subtree_root(&et, left_path,
+ right_path);
+
+ tmp_el = left_path->p_node[subtree_root].el;
+ blkno = left_path->p_node[subtree_root+1].bh->b_blocknr;
+ for (i = 0; i < le16_to_cpu(tmp_el->l_next_free_rec); i++) {
+ if (le64_to_cpu(tmp_el->l_recs[i].e_blkno) == blkno) {
+ *cpos_end = le32_to_cpu(tmp_el->l_recs[i+1].e_cpos);
+ break;
+ }
+ }
+
+ BUG_ON(i == le16_to_cpu(tmp_el->l_next_free_rec));
+
+out:
+ ocfs2_free_path(left_path);
+ ocfs2_free_path(right_path);
+ return ret;
+}
+
+/*
+ * Given a cpos and len, try to find the refcount record which contains cpos.
+ * 1. If cpos can be found in one refcount record, return the record.
+ * 2. If cpos can't be found, return a fake record which start from cpos
+ * and end at a small value between cpos+len and start of the next record.
+ * This fake record has r_refcount = 0.
+ */
+static int ocfs2_get_refcount_rec(struct ocfs2_caching_info *ci,
+ struct buffer_head *ref_root_bh,
+ u64 cpos, unsigned int len,
+ struct ocfs2_refcount_rec *ret_rec,
+ int *index,
+ struct buffer_head **ret_bh)
+{
+ int ret = 0, i, found;
+ u32 low_cpos, uninitialized_var(cpos_end);
+ struct ocfs2_extent_list *el;
+ struct ocfs2_extent_rec *rec = NULL;
+ struct ocfs2_extent_block *eb = NULL;
+ struct buffer_head *eb_bh = NULL, *ref_leaf_bh = NULL;
+ struct super_block *sb = ocfs2_metadata_cache_get_super(ci);
+ struct ocfs2_refcount_block *rb =
+ (struct ocfs2_refcount_block *)ref_root_bh->b_data;
+
+ if (!(le32_to_cpu(rb->rf_flags) & OCFS2_REFCOUNT_TREE_FL)) {
+ ocfs2_find_refcount_rec_in_rl(ci, ref_root_bh, cpos, len,
+ ret_rec, index);
+ *ret_bh = ref_root_bh;
+ get_bh(ref_root_bh);
+ return 0;
+ }
+
+ el = &rb->rf_list;
+ low_cpos = cpos & OCFS2_32BIT_POS_MASK;
+
+ if (el->l_tree_depth) {
+ ret = ocfs2_find_leaf(ci, el, low_cpos, &eb_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ eb = (struct ocfs2_extent_block *) eb_bh->b_data;
+ el = &eb->h_list;
+
+ if (el->l_tree_depth) {
+ ret = ocfs2_error(sb,
+ "refcount tree %llu has non zero tree depth in leaf btree tree block %llu\n",
+ (unsigned long long)ocfs2_metadata_cache_owner(ci),
+ (unsigned long long)eb_bh->b_blocknr);
+ goto out;
+ }
+ }
+
+ found = 0;
+ for (i = le16_to_cpu(el->l_next_free_rec) - 1; i >= 0; i--) {
+ rec = &el->l_recs[i];
+
+ if (le32_to_cpu(rec->e_cpos) <= low_cpos) {
+ found = 1;
+ break;
+ }
+ }
+
+ if (found) {
+ ret = ocfs2_get_refcount_cpos_end(ci, ref_root_bh,
+ eb, el, i, &cpos_end);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ if (cpos_end < low_cpos + len)
+ len = cpos_end - low_cpos;
+ }
+
+ ret = ocfs2_read_refcount_block(ci, le64_to_cpu(rec->e_blkno),
+ &ref_leaf_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ocfs2_find_refcount_rec_in_rl(ci, ref_leaf_bh, cpos, len,
+ ret_rec, index);
+ *ret_bh = ref_leaf_bh;
+out:
+ brelse(eb_bh);
+ return ret;
+}
+
+enum ocfs2_ref_rec_contig {
+ REF_CONTIG_NONE = 0,
+ REF_CONTIG_LEFT,
+ REF_CONTIG_RIGHT,
+ REF_CONTIG_LEFTRIGHT,
+};
+
+static enum ocfs2_ref_rec_contig
+ ocfs2_refcount_rec_adjacent(struct ocfs2_refcount_block *rb,
+ int index)
+{
+ if ((rb->rf_records.rl_recs[index].r_refcount ==
+ rb->rf_records.rl_recs[index + 1].r_refcount) &&
+ (le64_to_cpu(rb->rf_records.rl_recs[index].r_cpos) +
+ le32_to_cpu(rb->rf_records.rl_recs[index].r_clusters) ==
+ le64_to_cpu(rb->rf_records.rl_recs[index + 1].r_cpos)))
+ return REF_CONTIG_RIGHT;
+
+ return REF_CONTIG_NONE;
+}
+
+static enum ocfs2_ref_rec_contig
+ ocfs2_refcount_rec_contig(struct ocfs2_refcount_block *rb,
+ int index)
+{
+ enum ocfs2_ref_rec_contig ret = REF_CONTIG_NONE;
+
+ if (index < le16_to_cpu(rb->rf_records.rl_used) - 1)
+ ret = ocfs2_refcount_rec_adjacent(rb, index);
+
+ if (index > 0) {
+ enum ocfs2_ref_rec_contig tmp;
+
+ tmp = ocfs2_refcount_rec_adjacent(rb, index - 1);
+
+ if (tmp == REF_CONTIG_RIGHT) {
+ if (ret == REF_CONTIG_RIGHT)
+ ret = REF_CONTIG_LEFTRIGHT;
+ else
+ ret = REF_CONTIG_LEFT;
+ }
+ }
+
+ return ret;
+}
+
+static void ocfs2_rotate_refcount_rec_left(struct ocfs2_refcount_block *rb,
+ int index)
+{
+ BUG_ON(rb->rf_records.rl_recs[index].r_refcount !=
+ rb->rf_records.rl_recs[index+1].r_refcount);
+
+ le32_add_cpu(&rb->rf_records.rl_recs[index].r_clusters,
+ le32_to_cpu(rb->rf_records.rl_recs[index+1].r_clusters));
+
+ if (index < le16_to_cpu(rb->rf_records.rl_used) - 2)
+ memmove(&rb->rf_records.rl_recs[index + 1],
+ &rb->rf_records.rl_recs[index + 2],
+ sizeof(struct ocfs2_refcount_rec) *
+ (le16_to_cpu(rb->rf_records.rl_used) - index - 2));
+
+ memset(&rb->rf_records.rl_recs[le16_to_cpu(rb->rf_records.rl_used) - 1],
+ 0, sizeof(struct ocfs2_refcount_rec));
+ le16_add_cpu(&rb->rf_records.rl_used, -1);
+}
+
+/*
+ * Merge the refcount rec if we are contiguous with the adjacent recs.
+ */
+static void ocfs2_refcount_rec_merge(struct ocfs2_refcount_block *rb,
+ int index)
+{
+ enum ocfs2_ref_rec_contig contig =
+ ocfs2_refcount_rec_contig(rb, index);
+
+ if (contig == REF_CONTIG_NONE)
+ return;
+
+ if (contig == REF_CONTIG_LEFT || contig == REF_CONTIG_LEFTRIGHT) {
+ BUG_ON(index == 0);
+ index--;
+ }
+
+ ocfs2_rotate_refcount_rec_left(rb, index);
+
+ if (contig == REF_CONTIG_LEFTRIGHT)
+ ocfs2_rotate_refcount_rec_left(rb, index);
+}
+
+/*
+ * Change the refcount indexed by "index" in ref_bh.
+ * If refcount reaches 0, remove it.
+ */
+static int ocfs2_change_refcount_rec(handle_t *handle,
+ struct ocfs2_caching_info *ci,
+ struct buffer_head *ref_leaf_bh,
+ int index, int merge, int change)
+{
+ int ret;
+ struct ocfs2_refcount_block *rb =
+ (struct ocfs2_refcount_block *)ref_leaf_bh->b_data;
+ struct ocfs2_refcount_list *rl = &rb->rf_records;
+ struct ocfs2_refcount_rec *rec = &rl->rl_recs[index];
+
+ ret = ocfs2_journal_access_rb(handle, ci, ref_leaf_bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ trace_ocfs2_change_refcount_rec(
+ (unsigned long long)ocfs2_metadata_cache_owner(ci),
+ index, le32_to_cpu(rec->r_refcount), change);
+ le32_add_cpu(&rec->r_refcount, change);
+
+ if (!rec->r_refcount) {
+ if (index != le16_to_cpu(rl->rl_used) - 1) {
+ memmove(rec, rec + 1,
+ (le16_to_cpu(rl->rl_used) - index - 1) *
+ sizeof(struct ocfs2_refcount_rec));
+ memset(&rl->rl_recs[le16_to_cpu(rl->rl_used) - 1],
+ 0, sizeof(struct ocfs2_refcount_rec));
+ }
+
+ le16_add_cpu(&rl->rl_used, -1);
+ } else if (merge)
+ ocfs2_refcount_rec_merge(rb, index);
+
+ ocfs2_journal_dirty(handle, ref_leaf_bh);
+out:
+ return ret;
+}
+
+static int ocfs2_expand_inline_ref_root(handle_t *handle,
+ struct ocfs2_caching_info *ci,
+ struct buffer_head *ref_root_bh,
+ struct buffer_head **ref_leaf_bh,
+ struct ocfs2_alloc_context *meta_ac)
+{
+ int ret;
+ u16 suballoc_bit_start;
+ u32 num_got;
+ u64 suballoc_loc, blkno;
+ struct super_block *sb = ocfs2_metadata_cache_get_super(ci);
+ struct buffer_head *new_bh = NULL;
+ struct ocfs2_refcount_block *new_rb;
+ struct ocfs2_refcount_block *root_rb =
+ (struct ocfs2_refcount_block *)ref_root_bh->b_data;
+
+ ret = ocfs2_journal_access_rb(handle, ci, ref_root_bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_claim_metadata(handle, meta_ac, 1, &suballoc_loc,
+ &suballoc_bit_start, &num_got,
+ &blkno);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ new_bh = sb_getblk(sb, blkno);
+ if (new_bh == NULL) {
+ ret = -ENOMEM;
+ mlog_errno(ret);
+ goto out;
+ }
+ ocfs2_set_new_buffer_uptodate(ci, new_bh);
+
+ ret = ocfs2_journal_access_rb(handle, ci, new_bh,
+ OCFS2_JOURNAL_ACCESS_CREATE);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ /*
+ * Initialize ocfs2_refcount_block.
+ * It should contain the same information as the old root.
+ * so just memcpy it and change the corresponding field.
+ */
+ memcpy(new_bh->b_data, ref_root_bh->b_data, sb->s_blocksize);
+
+ new_rb = (struct ocfs2_refcount_block *)new_bh->b_data;
+ new_rb->rf_suballoc_slot = cpu_to_le16(meta_ac->ac_alloc_slot);
+ new_rb->rf_suballoc_loc = cpu_to_le64(suballoc_loc);
+ new_rb->rf_suballoc_bit = cpu_to_le16(suballoc_bit_start);
+ new_rb->rf_blkno = cpu_to_le64(blkno);
+ new_rb->rf_cpos = cpu_to_le32(0);
+ new_rb->rf_parent = cpu_to_le64(ref_root_bh->b_blocknr);
+ new_rb->rf_flags = cpu_to_le32(OCFS2_REFCOUNT_LEAF_FL);
+ ocfs2_journal_dirty(handle, new_bh);
+
+ /* Now change the root. */
+ memset(&root_rb->rf_list, 0, sb->s_blocksize -
+ offsetof(struct ocfs2_refcount_block, rf_list));
+ root_rb->rf_list.l_count = cpu_to_le16(ocfs2_extent_recs_per_rb(sb));
+ root_rb->rf_clusters = cpu_to_le32(1);
+ root_rb->rf_list.l_next_free_rec = cpu_to_le16(1);
+ root_rb->rf_list.l_recs[0].e_blkno = cpu_to_le64(blkno);
+ root_rb->rf_list.l_recs[0].e_leaf_clusters = cpu_to_le16(1);
+ root_rb->rf_flags = cpu_to_le32(OCFS2_REFCOUNT_TREE_FL);
+
+ ocfs2_journal_dirty(handle, ref_root_bh);
+
+ trace_ocfs2_expand_inline_ref_root((unsigned long long)blkno,
+ le16_to_cpu(new_rb->rf_records.rl_used));
+
+ *ref_leaf_bh = new_bh;
+ new_bh = NULL;
+out:
+ brelse(new_bh);
+ return ret;
+}
+
+static int ocfs2_refcount_rec_no_intersect(struct ocfs2_refcount_rec *prev,
+ struct ocfs2_refcount_rec *next)
+{
+ if (ocfs2_get_ref_rec_low_cpos(prev) + le32_to_cpu(prev->r_clusters) <=
+ ocfs2_get_ref_rec_low_cpos(next))
+ return 1;
+
+ return 0;
+}
+
+static int cmp_refcount_rec_by_low_cpos(const void *a, const void *b)
+{
+ const struct ocfs2_refcount_rec *l = a, *r = b;
+ u32 l_cpos = ocfs2_get_ref_rec_low_cpos(l);
+ u32 r_cpos = ocfs2_get_ref_rec_low_cpos(r);
+
+ if (l_cpos > r_cpos)
+ return 1;
+ if (l_cpos < r_cpos)
+ return -1;
+ return 0;
+}
+
+static int cmp_refcount_rec_by_cpos(const void *a, const void *b)
+{
+ const struct ocfs2_refcount_rec *l = a, *r = b;
+ u64 l_cpos = le64_to_cpu(l->r_cpos);
+ u64 r_cpos = le64_to_cpu(r->r_cpos);
+
+ if (l_cpos > r_cpos)
+ return 1;
+ if (l_cpos < r_cpos)
+ return -1;
+ return 0;
+}
+
+static void swap_refcount_rec(void *a, void *b, int size)
+{
+ struct ocfs2_refcount_rec *l = a, *r = b;
+
+ swap(*l, *r);
+}
+
+/*
+ * The refcount cpos are ordered by their 64bit cpos,
+ * But we will use the low 32 bit to be the e_cpos in the b-tree.
+ * So we need to make sure that this pos isn't intersected with others.
+ *
+ * Note: The refcount block is already sorted by their low 32 bit cpos,
+ * So just try the middle pos first, and we will exit when we find
+ * the good position.
+ */
+static int ocfs2_find_refcount_split_pos(struct ocfs2_refcount_list *rl,
+ u32 *split_pos, int *split_index)
+{
+ int num_used = le16_to_cpu(rl->rl_used);
+ int delta, middle = num_used / 2;
+
+ for (delta = 0; delta < middle; delta++) {
+ /* Let's check delta earlier than middle */
+ if (ocfs2_refcount_rec_no_intersect(
+ &rl->rl_recs[middle - delta - 1],
+ &rl->rl_recs[middle - delta])) {
+ *split_index = middle - delta;
+ break;
+ }
+
+ /* For even counts, don't walk off the end */
+ if ((middle + delta + 1) == num_used)
+ continue;
+
+ /* Now try delta past middle */
+ if (ocfs2_refcount_rec_no_intersect(
+ &rl->rl_recs[middle + delta],
+ &rl->rl_recs[middle + delta + 1])) {
+ *split_index = middle + delta + 1;
+ break;
+ }
+ }
+
+ if (delta >= middle)
+ return -ENOSPC;
+
+ *split_pos = ocfs2_get_ref_rec_low_cpos(&rl->rl_recs[*split_index]);
+ return 0;
+}
+
+static int ocfs2_divide_leaf_refcount_block(struct buffer_head *ref_leaf_bh,
+ struct buffer_head *new_bh,
+ u32 *split_cpos)
+{
+ int split_index = 0, num_moved, ret;
+ u32 cpos = 0;
+ struct ocfs2_refcount_block *rb =
+ (struct ocfs2_refcount_block *)ref_leaf_bh->b_data;
+ struct ocfs2_refcount_list *rl = &rb->rf_records;
+ struct ocfs2_refcount_block *new_rb =
+ (struct ocfs2_refcount_block *)new_bh->b_data;
+ struct ocfs2_refcount_list *new_rl = &new_rb->rf_records;
+
+ trace_ocfs2_divide_leaf_refcount_block(
+ (unsigned long long)ref_leaf_bh->b_blocknr,
+ le16_to_cpu(rl->rl_count), le16_to_cpu(rl->rl_used));
+
+ /*
+ * XXX: Improvement later.
+ * If we know all the high 32 bit cpos is the same, no need to sort.
+ *
+ * In order to make the whole process safe, we do:
+ * 1. sort the entries by their low 32 bit cpos first so that we can
+ * find the split cpos easily.
+ * 2. call ocfs2_insert_extent to insert the new refcount block.
+ * 3. move the refcount rec to the new block.
+ * 4. sort the entries by their 64 bit cpos.
+ * 5. dirty the new_rb and rb.
+ */
+ sort(&rl->rl_recs, le16_to_cpu(rl->rl_used),
+ sizeof(struct ocfs2_refcount_rec),
+ cmp_refcount_rec_by_low_cpos, swap_refcount_rec);
+
+ ret = ocfs2_find_refcount_split_pos(rl, &cpos, &split_index);
+ if (ret) {
+ mlog_errno(ret);
+ return ret;
+ }
+
+ new_rb->rf_cpos = cpu_to_le32(cpos);
+
+ /* move refcount records starting from split_index to the new block. */
+ num_moved = le16_to_cpu(rl->rl_used) - split_index;
+ memcpy(new_rl->rl_recs, &rl->rl_recs[split_index],
+ num_moved * sizeof(struct ocfs2_refcount_rec));
+
+ /*ok, remove the entries we just moved over to the other block. */
+ memset(&rl->rl_recs[split_index], 0,
+ num_moved * sizeof(struct ocfs2_refcount_rec));
+
+ /* change old and new rl_used accordingly. */
+ le16_add_cpu(&rl->rl_used, -num_moved);
+ new_rl->rl_used = cpu_to_le16(num_moved);
+
+ sort(&rl->rl_recs, le16_to_cpu(rl->rl_used),
+ sizeof(struct ocfs2_refcount_rec),
+ cmp_refcount_rec_by_cpos, swap_refcount_rec);
+
+ sort(&new_rl->rl_recs, le16_to_cpu(new_rl->rl_used),
+ sizeof(struct ocfs2_refcount_rec),
+ cmp_refcount_rec_by_cpos, swap_refcount_rec);
+
+ *split_cpos = cpos;
+ return 0;
+}
+
+static int ocfs2_new_leaf_refcount_block(handle_t *handle,
+ struct ocfs2_caching_info *ci,
+ struct buffer_head *ref_root_bh,
+ struct buffer_head *ref_leaf_bh,
+ struct ocfs2_alloc_context *meta_ac)
+{
+ int ret;
+ u16 suballoc_bit_start;
+ u32 num_got, new_cpos;
+ u64 suballoc_loc, blkno;
+ struct super_block *sb = ocfs2_metadata_cache_get_super(ci);
+ struct ocfs2_refcount_block *root_rb =
+ (struct ocfs2_refcount_block *)ref_root_bh->b_data;
+ struct buffer_head *new_bh = NULL;
+ struct ocfs2_refcount_block *new_rb;
+ struct ocfs2_extent_tree ref_et;
+
+ BUG_ON(!(le32_to_cpu(root_rb->rf_flags) & OCFS2_REFCOUNT_TREE_FL));
+
+ ret = ocfs2_journal_access_rb(handle, ci, ref_root_bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_journal_access_rb(handle, ci, ref_leaf_bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_claim_metadata(handle, meta_ac, 1, &suballoc_loc,
+ &suballoc_bit_start, &num_got,
+ &blkno);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ new_bh = sb_getblk(sb, blkno);
+ if (new_bh == NULL) {
+ ret = -ENOMEM;
+ mlog_errno(ret);
+ goto out;
+ }
+ ocfs2_set_new_buffer_uptodate(ci, new_bh);
+
+ ret = ocfs2_journal_access_rb(handle, ci, new_bh,
+ OCFS2_JOURNAL_ACCESS_CREATE);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ /* Initialize ocfs2_refcount_block. */
+ new_rb = (struct ocfs2_refcount_block *)new_bh->b_data;
+ memset(new_rb, 0, sb->s_blocksize);
+ strcpy((void *)new_rb, OCFS2_REFCOUNT_BLOCK_SIGNATURE);
+ new_rb->rf_suballoc_slot = cpu_to_le16(meta_ac->ac_alloc_slot);
+ new_rb->rf_suballoc_loc = cpu_to_le64(suballoc_loc);
+ new_rb->rf_suballoc_bit = cpu_to_le16(suballoc_bit_start);
+ new_rb->rf_fs_generation = cpu_to_le32(OCFS2_SB(sb)->fs_generation);
+ new_rb->rf_blkno = cpu_to_le64(blkno);
+ new_rb->rf_parent = cpu_to_le64(ref_root_bh->b_blocknr);
+ new_rb->rf_flags = cpu_to_le32(OCFS2_REFCOUNT_LEAF_FL);
+ new_rb->rf_records.rl_count =
+ cpu_to_le16(ocfs2_refcount_recs_per_rb(sb));
+ new_rb->rf_generation = root_rb->rf_generation;
+
+ ret = ocfs2_divide_leaf_refcount_block(ref_leaf_bh, new_bh, &new_cpos);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ocfs2_journal_dirty(handle, ref_leaf_bh);
+ ocfs2_journal_dirty(handle, new_bh);
+
+ ocfs2_init_refcount_extent_tree(&ref_et, ci, ref_root_bh);
+
+ trace_ocfs2_new_leaf_refcount_block(
+ (unsigned long long)new_bh->b_blocknr, new_cpos);
+
+ /* Insert the new leaf block with the specific offset cpos. */
+ ret = ocfs2_insert_extent(handle, &ref_et, new_cpos, new_bh->b_blocknr,
+ 1, 0, meta_ac);
+ if (ret)
+ mlog_errno(ret);
+
+out:
+ brelse(new_bh);
+ return ret;
+}
+
+static int ocfs2_expand_refcount_tree(handle_t *handle,
+ struct ocfs2_caching_info *ci,
+ struct buffer_head *ref_root_bh,
+ struct buffer_head *ref_leaf_bh,
+ struct ocfs2_alloc_context *meta_ac)
+{
+ int ret;
+ struct buffer_head *expand_bh = NULL;
+
+ if (ref_root_bh == ref_leaf_bh) {
+ /*
+ * the old root bh hasn't been expanded to a b-tree,
+ * so expand it first.
+ */
+ ret = ocfs2_expand_inline_ref_root(handle, ci, ref_root_bh,
+ &expand_bh, meta_ac);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ } else {
+ expand_bh = ref_leaf_bh;
+ get_bh(expand_bh);
+ }
+
+
+ /* Now add a new refcount block into the tree.*/
+ ret = ocfs2_new_leaf_refcount_block(handle, ci, ref_root_bh,
+ expand_bh, meta_ac);
+ if (ret)
+ mlog_errno(ret);
+out:
+ brelse(expand_bh);
+ return ret;
+}
+
+/*
+ * Adjust the extent rec in b-tree representing ref_leaf_bh.
+ *
+ * Only called when we have inserted a new refcount rec at index 0
+ * which means ocfs2_extent_rec.e_cpos may need some change.
+ */
+static int ocfs2_adjust_refcount_rec(handle_t *handle,
+ struct ocfs2_caching_info *ci,
+ struct buffer_head *ref_root_bh,
+ struct buffer_head *ref_leaf_bh,
+ struct ocfs2_refcount_rec *rec)
+{
+ int ret = 0, i;
+ u32 new_cpos, old_cpos;
+ struct ocfs2_path *path = NULL;
+ struct ocfs2_extent_tree et;
+ struct ocfs2_refcount_block *rb =
+ (struct ocfs2_refcount_block *)ref_root_bh->b_data;
+ struct ocfs2_extent_list *el;
+
+ if (!(le32_to_cpu(rb->rf_flags) & OCFS2_REFCOUNT_TREE_FL))
+ goto out;
+
+ rb = (struct ocfs2_refcount_block *)ref_leaf_bh->b_data;
+ old_cpos = le32_to_cpu(rb->rf_cpos);
+ new_cpos = le64_to_cpu(rec->r_cpos) & OCFS2_32BIT_POS_MASK;
+ if (old_cpos <= new_cpos)
+ goto out;
+
+ ocfs2_init_refcount_extent_tree(&et, ci, ref_root_bh);
+
+ path = ocfs2_new_path_from_et(&et);
+ if (!path) {
+ ret = -ENOMEM;
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_find_path(ci, path, old_cpos);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ /*
+ * 2 more credits, one for the leaf refcount block, one for
+ * the extent block contains the extent rec.
+ */
+ ret = ocfs2_extend_trans(handle, 2);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_journal_access_rb(handle, ci, ref_leaf_bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_journal_access_eb(handle, ci, path_leaf_bh(path),
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ /* change the leaf extent block first. */
+ el = path_leaf_el(path);
+
+ for (i = 0; i < le16_to_cpu(el->l_next_free_rec); i++)
+ if (le32_to_cpu(el->l_recs[i].e_cpos) == old_cpos)
+ break;
+
+ BUG_ON(i == le16_to_cpu(el->l_next_free_rec));
+
+ el->l_recs[i].e_cpos = cpu_to_le32(new_cpos);
+
+ /* change the r_cpos in the leaf block. */
+ rb->rf_cpos = cpu_to_le32(new_cpos);
+
+ ocfs2_journal_dirty(handle, path_leaf_bh(path));
+ ocfs2_journal_dirty(handle, ref_leaf_bh);
+
+out:
+ ocfs2_free_path(path);
+ return ret;
+}
+
+static int ocfs2_insert_refcount_rec(handle_t *handle,
+ struct ocfs2_caching_info *ci,
+ struct buffer_head *ref_root_bh,
+ struct buffer_head *ref_leaf_bh,
+ struct ocfs2_refcount_rec *rec,
+ int index, int merge,
+ struct ocfs2_alloc_context *meta_ac)
+{
+ int ret;
+ struct ocfs2_refcount_block *rb =
+ (struct ocfs2_refcount_block *)ref_leaf_bh->b_data;
+ struct ocfs2_refcount_list *rf_list = &rb->rf_records;
+ struct buffer_head *new_bh = NULL;
+
+ BUG_ON(le32_to_cpu(rb->rf_flags) & OCFS2_REFCOUNT_TREE_FL);
+
+ if (rf_list->rl_used == rf_list->rl_count) {
+ u64 cpos = le64_to_cpu(rec->r_cpos);
+ u32 len = le32_to_cpu(rec->r_clusters);
+
+ ret = ocfs2_expand_refcount_tree(handle, ci, ref_root_bh,
+ ref_leaf_bh, meta_ac);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_get_refcount_rec(ci, ref_root_bh,
+ cpos, len, NULL, &index,
+ &new_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ref_leaf_bh = new_bh;
+ rb = (struct ocfs2_refcount_block *)ref_leaf_bh->b_data;
+ rf_list = &rb->rf_records;
+ }
+
+ ret = ocfs2_journal_access_rb(handle, ci, ref_leaf_bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ if (index < le16_to_cpu(rf_list->rl_used))
+ memmove(&rf_list->rl_recs[index + 1],
+ &rf_list->rl_recs[index],
+ (le16_to_cpu(rf_list->rl_used) - index) *
+ sizeof(struct ocfs2_refcount_rec));
+
+ trace_ocfs2_insert_refcount_rec(
+ (unsigned long long)ref_leaf_bh->b_blocknr, index,
+ (unsigned long long)le64_to_cpu(rec->r_cpos),
+ le32_to_cpu(rec->r_clusters), le32_to_cpu(rec->r_refcount));
+
+ rf_list->rl_recs[index] = *rec;
+
+ le16_add_cpu(&rf_list->rl_used, 1);
+
+ if (merge)
+ ocfs2_refcount_rec_merge(rb, index);
+
+ ocfs2_journal_dirty(handle, ref_leaf_bh);
+
+ if (index == 0) {
+ ret = ocfs2_adjust_refcount_rec(handle, ci,
+ ref_root_bh,
+ ref_leaf_bh, rec);
+ if (ret)
+ mlog_errno(ret);
+ }
+out:
+ brelse(new_bh);
+ return ret;
+}
+
+/*
+ * Split the refcount_rec indexed by "index" in ref_leaf_bh.
+ * This is much simple than our b-tree code.
+ * split_rec is the new refcount rec we want to insert.
+ * If split_rec->r_refcount > 0, we are changing the refcount(in case we
+ * increase refcount or decrease a refcount to non-zero).
+ * If split_rec->r_refcount == 0, we are punching a hole in current refcount
+ * rec( in case we decrease a refcount to zero).
+ */
+static int ocfs2_split_refcount_rec(handle_t *handle,
+ struct ocfs2_caching_info *ci,
+ struct buffer_head *ref_root_bh,
+ struct buffer_head *ref_leaf_bh,
+ struct ocfs2_refcount_rec *split_rec,
+ int index, int merge,
+ struct ocfs2_alloc_context *meta_ac,
+ struct ocfs2_cached_dealloc_ctxt *dealloc)
+{
+ int ret, recs_need;
+ u32 len;
+ struct ocfs2_refcount_block *rb =
+ (struct ocfs2_refcount_block *)ref_leaf_bh->b_data;
+ struct ocfs2_refcount_list *rf_list = &rb->rf_records;
+ struct ocfs2_refcount_rec *orig_rec = &rf_list->rl_recs[index];
+ struct ocfs2_refcount_rec *tail_rec = NULL;
+ struct buffer_head *new_bh = NULL;
+
+ BUG_ON(le32_to_cpu(rb->rf_flags) & OCFS2_REFCOUNT_TREE_FL);
+
+ trace_ocfs2_split_refcount_rec(le64_to_cpu(orig_rec->r_cpos),
+ le32_to_cpu(orig_rec->r_clusters),
+ le32_to_cpu(orig_rec->r_refcount),
+ le64_to_cpu(split_rec->r_cpos),
+ le32_to_cpu(split_rec->r_clusters),
+ le32_to_cpu(split_rec->r_refcount));
+
+ /*
+ * If we just need to split the header or tail clusters,
+ * no more recs are needed, just split is OK.
+ * Otherwise we at least need one new recs.
+ */
+ if (!split_rec->r_refcount &&
+ (split_rec->r_cpos == orig_rec->r_cpos ||
+ le64_to_cpu(split_rec->r_cpos) +
+ le32_to_cpu(split_rec->r_clusters) ==
+ le64_to_cpu(orig_rec->r_cpos) + le32_to_cpu(orig_rec->r_clusters)))
+ recs_need = 0;
+ else
+ recs_need = 1;
+
+ /*
+ * We need one more rec if we split in the middle and the new rec have
+ * some refcount in it.
+ */
+ if (split_rec->r_refcount &&
+ (split_rec->r_cpos != orig_rec->r_cpos &&
+ le64_to_cpu(split_rec->r_cpos) +
+ le32_to_cpu(split_rec->r_clusters) !=
+ le64_to_cpu(orig_rec->r_cpos) + le32_to_cpu(orig_rec->r_clusters)))
+ recs_need++;
+
+ /* If the leaf block don't have enough record, expand it. */
+ if (le16_to_cpu(rf_list->rl_used) + recs_need >
+ le16_to_cpu(rf_list->rl_count)) {
+ struct ocfs2_refcount_rec tmp_rec;
+ u64 cpos = le64_to_cpu(orig_rec->r_cpos);
+ len = le32_to_cpu(orig_rec->r_clusters);
+ ret = ocfs2_expand_refcount_tree(handle, ci, ref_root_bh,
+ ref_leaf_bh, meta_ac);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ /*
+ * We have to re-get it since now cpos may be moved to
+ * another leaf block.
+ */
+ ret = ocfs2_get_refcount_rec(ci, ref_root_bh,
+ cpos, len, &tmp_rec, &index,
+ &new_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ref_leaf_bh = new_bh;
+ rb = (struct ocfs2_refcount_block *)ref_leaf_bh->b_data;
+ rf_list = &rb->rf_records;
+ orig_rec = &rf_list->rl_recs[index];
+ }
+
+ ret = ocfs2_journal_access_rb(handle, ci, ref_leaf_bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ /*
+ * We have calculated out how many new records we need and store
+ * in recs_need, so spare enough space first by moving the records
+ * after "index" to the end.
+ */
+ if (index != le16_to_cpu(rf_list->rl_used) - 1)
+ memmove(&rf_list->rl_recs[index + 1 + recs_need],
+ &rf_list->rl_recs[index + 1],
+ (le16_to_cpu(rf_list->rl_used) - index - 1) *
+ sizeof(struct ocfs2_refcount_rec));
+
+ len = (le64_to_cpu(orig_rec->r_cpos) +
+ le32_to_cpu(orig_rec->r_clusters)) -
+ (le64_to_cpu(split_rec->r_cpos) +
+ le32_to_cpu(split_rec->r_clusters));
+
+ /*
+ * If we have "len", the we will split in the tail and move it
+ * to the end of the space we have just spared.
+ */
+ if (len) {
+ tail_rec = &rf_list->rl_recs[index + recs_need];
+
+ memcpy(tail_rec, orig_rec, sizeof(struct ocfs2_refcount_rec));
+ le64_add_cpu(&tail_rec->r_cpos,
+ le32_to_cpu(tail_rec->r_clusters) - len);
+ tail_rec->r_clusters = cpu_to_le32(len);
+ }
+
+ /*
+ * If the split pos isn't the same as the original one, we need to
+ * split in the head.
+ *
+ * Note: We have the chance that split_rec.r_refcount = 0,
+ * recs_need = 0 and len > 0, which means we just cut the head from
+ * the orig_rec and in that case we have done some modification in
+ * orig_rec above, so the check for r_cpos is faked.
+ */
+ if (split_rec->r_cpos != orig_rec->r_cpos && tail_rec != orig_rec) {
+ len = le64_to_cpu(split_rec->r_cpos) -
+ le64_to_cpu(orig_rec->r_cpos);
+ orig_rec->r_clusters = cpu_to_le32(len);
+ index++;
+ }
+
+ le16_add_cpu(&rf_list->rl_used, recs_need);
+
+ if (split_rec->r_refcount) {
+ rf_list->rl_recs[index] = *split_rec;
+ trace_ocfs2_split_refcount_rec_insert(
+ (unsigned long long)ref_leaf_bh->b_blocknr, index,
+ (unsigned long long)le64_to_cpu(split_rec->r_cpos),
+ le32_to_cpu(split_rec->r_clusters),
+ le32_to_cpu(split_rec->r_refcount));
+
+ if (merge)
+ ocfs2_refcount_rec_merge(rb, index);
+ }
+
+ ocfs2_journal_dirty(handle, ref_leaf_bh);
+
+out:
+ brelse(new_bh);
+ return ret;
+}
+
+static int __ocfs2_increase_refcount(handle_t *handle,
+ struct ocfs2_caching_info *ci,
+ struct buffer_head *ref_root_bh,
+ u64 cpos, u32 len, int merge,
+ struct ocfs2_alloc_context *meta_ac,
+ struct ocfs2_cached_dealloc_ctxt *dealloc)
+{
+ int ret = 0, index;
+ struct buffer_head *ref_leaf_bh = NULL;
+ struct ocfs2_refcount_rec rec;
+ unsigned int set_len = 0;
+
+ trace_ocfs2_increase_refcount_begin(
+ (unsigned long long)ocfs2_metadata_cache_owner(ci),
+ (unsigned long long)cpos, len);
+
+ while (len) {
+ ret = ocfs2_get_refcount_rec(ci, ref_root_bh,
+ cpos, len, &rec, &index,
+ &ref_leaf_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ set_len = le32_to_cpu(rec.r_clusters);
+
+ /*
+ * Here we may meet with 3 situations:
+ *
+ * 1. If we find an already existing record, and the length
+ * is the same, cool, we just need to increase the r_refcount
+ * and it is OK.
+ * 2. If we find a hole, just insert it with r_refcount = 1.
+ * 3. If we are in the middle of one extent record, split
+ * it.
+ */
+ if (rec.r_refcount && le64_to_cpu(rec.r_cpos) == cpos &&
+ set_len <= len) {
+ trace_ocfs2_increase_refcount_change(
+ (unsigned long long)cpos, set_len,
+ le32_to_cpu(rec.r_refcount));
+ ret = ocfs2_change_refcount_rec(handle, ci,
+ ref_leaf_bh, index,
+ merge, 1);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ } else if (!rec.r_refcount) {
+ rec.r_refcount = cpu_to_le32(1);
+
+ trace_ocfs2_increase_refcount_insert(
+ (unsigned long long)le64_to_cpu(rec.r_cpos),
+ set_len);
+ ret = ocfs2_insert_refcount_rec(handle, ci, ref_root_bh,
+ ref_leaf_bh,
+ &rec, index,
+ merge, meta_ac);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ } else {
+ set_len = min((u64)(cpos + len),
+ le64_to_cpu(rec.r_cpos) + set_len) - cpos;
+ rec.r_cpos = cpu_to_le64(cpos);
+ rec.r_clusters = cpu_to_le32(set_len);
+ le32_add_cpu(&rec.r_refcount, 1);
+
+ trace_ocfs2_increase_refcount_split(
+ (unsigned long long)le64_to_cpu(rec.r_cpos),
+ set_len, le32_to_cpu(rec.r_refcount));
+ ret = ocfs2_split_refcount_rec(handle, ci,
+ ref_root_bh, ref_leaf_bh,
+ &rec, index, merge,
+ meta_ac, dealloc);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
+ cpos += set_len;
+ len -= set_len;
+ brelse(ref_leaf_bh);
+ ref_leaf_bh = NULL;
+ }
+
+out:
+ brelse(ref_leaf_bh);
+ return ret;
+}
+
+static int ocfs2_remove_refcount_extent(handle_t *handle,
+ struct ocfs2_caching_info *ci,
+ struct buffer_head *ref_root_bh,
+ struct buffer_head *ref_leaf_bh,
+ struct ocfs2_alloc_context *meta_ac,
+ struct ocfs2_cached_dealloc_ctxt *dealloc)
+{
+ int ret;
+ struct super_block *sb = ocfs2_metadata_cache_get_super(ci);
+ struct ocfs2_refcount_block *rb =
+ (struct ocfs2_refcount_block *)ref_leaf_bh->b_data;
+ struct ocfs2_extent_tree et;
+
+ BUG_ON(rb->rf_records.rl_used);
+
+ trace_ocfs2_remove_refcount_extent(
+ (unsigned long long)ocfs2_metadata_cache_owner(ci),
+ (unsigned long long)ref_leaf_bh->b_blocknr,
+ le32_to_cpu(rb->rf_cpos));
+
+ ocfs2_init_refcount_extent_tree(&et, ci, ref_root_bh);
+ ret = ocfs2_remove_extent(handle, &et, le32_to_cpu(rb->rf_cpos),
+ 1, meta_ac, dealloc);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ocfs2_remove_from_cache(ci, ref_leaf_bh);
+
+ /*
+ * add the freed block to the dealloc so that it will be freed
+ * when we run dealloc.
+ */
+ ret = ocfs2_cache_block_dealloc(dealloc, EXTENT_ALLOC_SYSTEM_INODE,
+ le16_to_cpu(rb->rf_suballoc_slot),
+ le64_to_cpu(rb->rf_suballoc_loc),
+ le64_to_cpu(rb->rf_blkno),
+ le16_to_cpu(rb->rf_suballoc_bit));
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_journal_access_rb(handle, ci, ref_root_bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ rb = (struct ocfs2_refcount_block *)ref_root_bh->b_data;
+
+ le32_add_cpu(&rb->rf_clusters, -1);
+
+ /*
+ * check whether we need to restore the root refcount block if
+ * there is no leaf extent block at atll.
+ */
+ if (!rb->rf_list.l_next_free_rec) {
+ BUG_ON(rb->rf_clusters);
+
+ trace_ocfs2_restore_refcount_block(
+ (unsigned long long)ref_root_bh->b_blocknr);
+
+ rb->rf_flags = 0;
+ rb->rf_parent = 0;
+ rb->rf_cpos = 0;
+ memset(&rb->rf_records, 0, sb->s_blocksize -
+ offsetof(struct ocfs2_refcount_block, rf_records));
+ rb->rf_records.rl_count =
+ cpu_to_le16(ocfs2_refcount_recs_per_rb(sb));
+ }
+
+ ocfs2_journal_dirty(handle, ref_root_bh);
+
+out:
+ return ret;
+}
+
+int ocfs2_increase_refcount(handle_t *handle,
+ struct ocfs2_caching_info *ci,
+ struct buffer_head *ref_root_bh,
+ u64 cpos, u32 len,
+ struct ocfs2_alloc_context *meta_ac,
+ struct ocfs2_cached_dealloc_ctxt *dealloc)
+{
+ return __ocfs2_increase_refcount(handle, ci, ref_root_bh,
+ cpos, len, 1,
+ meta_ac, dealloc);
+}
+
+static int ocfs2_decrease_refcount_rec(handle_t *handle,
+ struct ocfs2_caching_info *ci,
+ struct buffer_head *ref_root_bh,
+ struct buffer_head *ref_leaf_bh,
+ int index, u64 cpos, unsigned int len,
+ struct ocfs2_alloc_context *meta_ac,
+ struct ocfs2_cached_dealloc_ctxt *dealloc)
+{
+ int ret;
+ struct ocfs2_refcount_block *rb =
+ (struct ocfs2_refcount_block *)ref_leaf_bh->b_data;
+ struct ocfs2_refcount_rec *rec = &rb->rf_records.rl_recs[index];
+
+ BUG_ON(cpos < le64_to_cpu(rec->r_cpos));
+ BUG_ON(cpos + len >
+ le64_to_cpu(rec->r_cpos) + le32_to_cpu(rec->r_clusters));
+
+ trace_ocfs2_decrease_refcount_rec(
+ (unsigned long long)ocfs2_metadata_cache_owner(ci),
+ (unsigned long long)cpos, len);
+
+ if (cpos == le64_to_cpu(rec->r_cpos) &&
+ len == le32_to_cpu(rec->r_clusters))
+ ret = ocfs2_change_refcount_rec(handle, ci,
+ ref_leaf_bh, index, 1, -1);
+ else {
+ struct ocfs2_refcount_rec split = *rec;
+ split.r_cpos = cpu_to_le64(cpos);
+ split.r_clusters = cpu_to_le32(len);
+
+ le32_add_cpu(&split.r_refcount, -1);
+
+ ret = ocfs2_split_refcount_rec(handle, ci,
+ ref_root_bh, ref_leaf_bh,
+ &split, index, 1,
+ meta_ac, dealloc);
+ }
+
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ /* Remove the leaf refcount block if it contains no refcount record. */
+ if (!rb->rf_records.rl_used && ref_leaf_bh != ref_root_bh) {
+ ret = ocfs2_remove_refcount_extent(handle, ci, ref_root_bh,
+ ref_leaf_bh, meta_ac,
+ dealloc);
+ if (ret)
+ mlog_errno(ret);
+ }
+
+out:
+ return ret;
+}
+
+static int __ocfs2_decrease_refcount(handle_t *handle,
+ struct ocfs2_caching_info *ci,
+ struct buffer_head *ref_root_bh,
+ u64 cpos, u32 len,
+ struct ocfs2_alloc_context *meta_ac,
+ struct ocfs2_cached_dealloc_ctxt *dealloc,
+ int delete)
+{
+ int ret = 0, index = 0;
+ struct ocfs2_refcount_rec rec;
+ unsigned int r_count = 0, r_len;
+ struct super_block *sb = ocfs2_metadata_cache_get_super(ci);
+ struct buffer_head *ref_leaf_bh = NULL;
+
+ trace_ocfs2_decrease_refcount(
+ (unsigned long long)ocfs2_metadata_cache_owner(ci),
+ (unsigned long long)cpos, len, delete);
+
+ while (len) {
+ ret = ocfs2_get_refcount_rec(ci, ref_root_bh,
+ cpos, len, &rec, &index,
+ &ref_leaf_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ r_count = le32_to_cpu(rec.r_refcount);
+ BUG_ON(r_count == 0);
+ if (!delete)
+ BUG_ON(r_count > 1);
+
+ r_len = min((u64)(cpos + len), le64_to_cpu(rec.r_cpos) +
+ le32_to_cpu(rec.r_clusters)) - cpos;
+
+ ret = ocfs2_decrease_refcount_rec(handle, ci, ref_root_bh,
+ ref_leaf_bh, index,
+ cpos, r_len,
+ meta_ac, dealloc);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ if (le32_to_cpu(rec.r_refcount) == 1 && delete) {
+ ret = ocfs2_cache_cluster_dealloc(dealloc,
+ ocfs2_clusters_to_blocks(sb, cpos),
+ r_len);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
+ cpos += r_len;
+ len -= r_len;
+ brelse(ref_leaf_bh);
+ ref_leaf_bh = NULL;
+ }
+
+out:
+ brelse(ref_leaf_bh);
+ return ret;
+}
+
+/* Caller must hold refcount tree lock. */
+int ocfs2_decrease_refcount(struct inode *inode,
+ handle_t *handle, u32 cpos, u32 len,
+ struct ocfs2_alloc_context *meta_ac,
+ struct ocfs2_cached_dealloc_ctxt *dealloc,
+ int delete)
+{
+ int ret;
+ u64 ref_blkno;
+ struct buffer_head *ref_root_bh = NULL;
+ struct ocfs2_refcount_tree *tree;
+
+ BUG_ON(!ocfs2_is_refcount_inode(inode));
+
+ ret = ocfs2_get_refcount_block(inode, &ref_blkno);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_get_refcount_tree(OCFS2_SB(inode->i_sb), ref_blkno, &tree);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_read_refcount_block(&tree->rf_ci, tree->rf_blkno,
+ &ref_root_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = __ocfs2_decrease_refcount(handle, &tree->rf_ci, ref_root_bh,
+ cpos, len, meta_ac, dealloc, delete);
+ if (ret)
+ mlog_errno(ret);
+out:
+ brelse(ref_root_bh);
+ return ret;
+}
+
+/*
+ * Mark the already-existing extent at cpos as refcounted for len clusters.
+ * This adds the refcount extent flag.
+ *
+ * If the existing extent is larger than the request, initiate a
+ * split. An attempt will be made at merging with adjacent extents.
+ *
+ * The caller is responsible for passing down meta_ac if we'll need it.
+ */
+static int ocfs2_mark_extent_refcounted(struct inode *inode,
+ struct ocfs2_extent_tree *et,
+ handle_t *handle, u32 cpos,
+ u32 len, u32 phys,
+ struct ocfs2_alloc_context *meta_ac,
+ struct ocfs2_cached_dealloc_ctxt *dealloc)
+{
+ int ret;
+
+ trace_ocfs2_mark_extent_refcounted(OCFS2_I(inode)->ip_blkno,
+ cpos, len, phys);
+
+ if (!ocfs2_refcount_tree(OCFS2_SB(inode->i_sb))) {
+ ret = ocfs2_error(inode->i_sb, "Inode %lu want to use refcount tree, but the feature bit is not set in the super block\n",
+ inode->i_ino);
+ goto out;
+ }
+
+ ret = ocfs2_change_extent_flag(handle, et, cpos,
+ len, phys, meta_ac, dealloc,
+ OCFS2_EXT_REFCOUNTED, 0);
+ if (ret)
+ mlog_errno(ret);
+
+out:
+ return ret;
+}
+
+/*
+ * Given some contiguous physical clusters, calculate what we need
+ * for modifying their refcount.
+ */
+static int ocfs2_calc_refcount_meta_credits(struct super_block *sb,
+ struct ocfs2_caching_info *ci,
+ struct buffer_head *ref_root_bh,
+ u64 start_cpos,
+ u32 clusters,
+ int *meta_add,
+ int *credits)
+{
+ int ret = 0, index, ref_blocks = 0, recs_add = 0;
+ u64 cpos = start_cpos;
+ struct ocfs2_refcount_block *rb;
+ struct ocfs2_refcount_rec rec;
+ struct buffer_head *ref_leaf_bh = NULL, *prev_bh = NULL;
+ u32 len;
+
+ while (clusters) {
+ ret = ocfs2_get_refcount_rec(ci, ref_root_bh,
+ cpos, clusters, &rec,
+ &index, &ref_leaf_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ if (ref_leaf_bh != prev_bh) {
+ /*
+ * Now we encounter a new leaf block, so calculate
+ * whether we need to extend the old leaf.
+ */
+ if (prev_bh) {
+ rb = (struct ocfs2_refcount_block *)
+ prev_bh->b_data;
+
+ if (le16_to_cpu(rb->rf_records.rl_used) +
+ recs_add >
+ le16_to_cpu(rb->rf_records.rl_count))
+ ref_blocks++;
+ }
+
+ recs_add = 0;
+ *credits += 1;
+ brelse(prev_bh);
+ prev_bh = ref_leaf_bh;
+ get_bh(prev_bh);
+ }
+
+ trace_ocfs2_calc_refcount_meta_credits_iterate(
+ recs_add, (unsigned long long)cpos, clusters,
+ (unsigned long long)le64_to_cpu(rec.r_cpos),
+ le32_to_cpu(rec.r_clusters),
+ le32_to_cpu(rec.r_refcount), index);
+
+ len = min((u64)cpos + clusters, le64_to_cpu(rec.r_cpos) +
+ le32_to_cpu(rec.r_clusters)) - cpos;
+ /*
+ * We record all the records which will be inserted to the
+ * same refcount block, so that we can tell exactly whether
+ * we need a new refcount block or not.
+ *
+ * If we will insert a new one, this is easy and only happens
+ * during adding refcounted flag to the extent, so we don't
+ * have a chance of spliting. We just need one record.
+ *
+ * If the refcount rec already exists, that would be a little
+ * complicated. we may have to:
+ * 1) split at the beginning if the start pos isn't aligned.
+ * we need 1 more record in this case.
+ * 2) split int the end if the end pos isn't aligned.
+ * we need 1 more record in this case.
+ * 3) split in the middle because of file system fragmentation.
+ * we need 2 more records in this case(we can't detect this
+ * beforehand, so always think of the worst case).
+ */
+ if (rec.r_refcount) {
+ recs_add += 2;
+ /* Check whether we need a split at the beginning. */
+ if (cpos == start_cpos &&
+ cpos != le64_to_cpu(rec.r_cpos))
+ recs_add++;
+
+ /* Check whether we need a split in the end. */
+ if (cpos + clusters < le64_to_cpu(rec.r_cpos) +
+ le32_to_cpu(rec.r_clusters))
+ recs_add++;
+ } else
+ recs_add++;
+
+ brelse(ref_leaf_bh);
+ ref_leaf_bh = NULL;
+ clusters -= len;
+ cpos += len;
+ }
+
+ if (prev_bh) {
+ rb = (struct ocfs2_refcount_block *)prev_bh->b_data;
+
+ if (le16_to_cpu(rb->rf_records.rl_used) + recs_add >
+ le16_to_cpu(rb->rf_records.rl_count))
+ ref_blocks++;
+
+ *credits += 1;
+ }
+
+ if (!ref_blocks)
+ goto out;
+
+ *meta_add += ref_blocks;
+ *credits += ref_blocks;
+
+ /*
+ * So we may need ref_blocks to insert into the tree.
+ * That also means we need to change the b-tree and add that number
+ * of records since we never merge them.
+ * We need one more block for expansion since the new created leaf
+ * block is also full and needs split.
+ */
+ rb = (struct ocfs2_refcount_block *)ref_root_bh->b_data;
+ if (le32_to_cpu(rb->rf_flags) & OCFS2_REFCOUNT_TREE_FL) {
+ struct ocfs2_extent_tree et;
+
+ ocfs2_init_refcount_extent_tree(&et, ci, ref_root_bh);
+ *meta_add += ocfs2_extend_meta_needed(et.et_root_el);
+ *credits += ocfs2_calc_extend_credits(sb,
+ et.et_root_el);
+ } else {
+ *credits += OCFS2_EXPAND_REFCOUNT_TREE_CREDITS;
+ *meta_add += 1;
+ }
+
+out:
+
+ trace_ocfs2_calc_refcount_meta_credits(
+ (unsigned long long)start_cpos, clusters,
+ *meta_add, *credits);
+ brelse(ref_leaf_bh);
+ brelse(prev_bh);
+ return ret;
+}
+
+/*
+ * For refcount tree, we will decrease some contiguous clusters
+ * refcount count, so just go through it to see how many blocks
+ * we gonna touch and whether we need to create new blocks.
+ *
+ * Normally the refcount blocks store these refcount should be
+ * contiguous also, so that we can get the number easily.
+ * We will at most add split 2 refcount records and 2 more
+ * refcount blocks, so just check it in a rough way.
+ *
+ * Caller must hold refcount tree lock.
+ */
+int ocfs2_prepare_refcount_change_for_del(struct inode *inode,
+ u64 refcount_loc,
+ u64 phys_blkno,
+ u32 clusters,
+ int *credits,
+ int *ref_blocks)
+{
+ int ret;
+ struct buffer_head *ref_root_bh = NULL;
+ struct ocfs2_refcount_tree *tree;
+ u64 start_cpos = ocfs2_blocks_to_clusters(inode->i_sb, phys_blkno);
+
+ if (!ocfs2_refcount_tree(OCFS2_SB(inode->i_sb))) {
+ ret = ocfs2_error(inode->i_sb, "Inode %lu want to use refcount tree, but the feature bit is not set in the super block\n",
+ inode->i_ino);
+ goto out;
+ }
+
+ BUG_ON(!ocfs2_is_refcount_inode(inode));
+
+ ret = ocfs2_get_refcount_tree(OCFS2_SB(inode->i_sb),
+ refcount_loc, &tree);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_read_refcount_block(&tree->rf_ci, refcount_loc,
+ &ref_root_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_calc_refcount_meta_credits(inode->i_sb,
+ &tree->rf_ci,
+ ref_root_bh,
+ start_cpos, clusters,
+ ref_blocks, credits);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ trace_ocfs2_prepare_refcount_change_for_del(*ref_blocks, *credits);
+
+out:
+ brelse(ref_root_bh);
+ return ret;
+}
+
+#define MAX_CONTIG_BYTES 1048576
+
+static inline unsigned int ocfs2_cow_contig_clusters(struct super_block *sb)
+{
+ return ocfs2_clusters_for_bytes(sb, MAX_CONTIG_BYTES);
+}
+
+static inline unsigned int ocfs2_cow_contig_mask(struct super_block *sb)
+{
+ return ~(ocfs2_cow_contig_clusters(sb) - 1);
+}
+
+/*
+ * Given an extent that starts at 'start' and an I/O that starts at 'cpos',
+ * find an offset (start + (n * contig_clusters)) that is closest to cpos
+ * while still being less than or equal to it.
+ *
+ * The goal is to break the extent at a multiple of contig_clusters.
+ */
+static inline unsigned int ocfs2_cow_align_start(struct super_block *sb,
+ unsigned int start,
+ unsigned int cpos)
+{
+ BUG_ON(start > cpos);
+
+ return start + ((cpos - start) & ocfs2_cow_contig_mask(sb));
+}
+
+/*
+ * Given a cluster count of len, pad it out so that it is a multiple
+ * of contig_clusters.
+ */
+static inline unsigned int ocfs2_cow_align_length(struct super_block *sb,
+ unsigned int len)
+{
+ unsigned int padded =
+ (len + (ocfs2_cow_contig_clusters(sb) - 1)) &
+ ocfs2_cow_contig_mask(sb);
+
+ /* Did we wrap? */
+ if (padded < len)
+ padded = UINT_MAX;
+
+ return padded;
+}
+
+/*
+ * Calculate out the start and number of virtual clusters we need to to CoW.
+ *
+ * cpos is vitual start cluster position we want to do CoW in a
+ * file and write_len is the cluster length.
+ * max_cpos is the place where we want to stop CoW intentionally.
+ *
+ * Normal we will start CoW from the beginning of extent record cotaining cpos.
+ * We try to break up extents on boundaries of MAX_CONTIG_BYTES so that we
+ * get good I/O from the resulting extent tree.
+ */
+static int ocfs2_refcount_cal_cow_clusters(struct inode *inode,
+ struct ocfs2_extent_list *el,
+ u32 cpos,
+ u32 write_len,
+ u32 max_cpos,
+ u32 *cow_start,
+ u32 *cow_len)
+{
+ int ret = 0;
+ int tree_height = le16_to_cpu(el->l_tree_depth), i;
+ struct buffer_head *eb_bh = NULL;
+ struct ocfs2_extent_block *eb = NULL;
+ struct ocfs2_extent_rec *rec;
+ unsigned int want_clusters, rec_end = 0;
+ int contig_clusters = ocfs2_cow_contig_clusters(inode->i_sb);
+ int leaf_clusters;
+
+ BUG_ON(cpos + write_len > max_cpos);
+
+ if (tree_height > 0) {
+ ret = ocfs2_find_leaf(INODE_CACHE(inode), el, cpos, &eb_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ eb = (struct ocfs2_extent_block *) eb_bh->b_data;
+ el = &eb->h_list;
+
+ if (el->l_tree_depth) {
+ ret = ocfs2_error(inode->i_sb,
+ "Inode %lu has non zero tree depth in leaf block %llu\n",
+ inode->i_ino,
+ (unsigned long long)eb_bh->b_blocknr);
+ goto out;
+ }
+ }
+
+ *cow_len = 0;
+ for (i = 0; i < le16_to_cpu(el->l_next_free_rec); i++) {
+ rec = &el->l_recs[i];
+
+ if (ocfs2_is_empty_extent(rec)) {
+ mlog_bug_on_msg(i != 0, "Inode %lu has empty record in "
+ "index %d\n", inode->i_ino, i);
+ continue;
+ }
+
+ if (le32_to_cpu(rec->e_cpos) +
+ le16_to_cpu(rec->e_leaf_clusters) <= cpos)
+ continue;
+
+ if (*cow_len == 0) {
+ /*
+ * We should find a refcounted record in the
+ * first pass.
+ */
+ BUG_ON(!(rec->e_flags & OCFS2_EXT_REFCOUNTED));
+ *cow_start = le32_to_cpu(rec->e_cpos);
+ }
+
+ /*
+ * If we encounter a hole, a non-refcounted record or
+ * pass the max_cpos, stop the search.
+ */
+ if ((!(rec->e_flags & OCFS2_EXT_REFCOUNTED)) ||
+ (*cow_len && rec_end != le32_to_cpu(rec->e_cpos)) ||
+ (max_cpos <= le32_to_cpu(rec->e_cpos)))
+ break;
+
+ leaf_clusters = le16_to_cpu(rec->e_leaf_clusters);
+ rec_end = le32_to_cpu(rec->e_cpos) + leaf_clusters;
+ if (rec_end > max_cpos) {
+ rec_end = max_cpos;
+ leaf_clusters = rec_end - le32_to_cpu(rec->e_cpos);
+ }
+
+ /*
+ * How many clusters do we actually need from
+ * this extent? First we see how many we actually
+ * need to complete the write. If that's smaller
+ * than contig_clusters, we try for contig_clusters.
+ */
+ if (!*cow_len)
+ want_clusters = write_len;
+ else
+ want_clusters = (cpos + write_len) -
+ (*cow_start + *cow_len);
+ if (want_clusters < contig_clusters)
+ want_clusters = contig_clusters;
+
+ /*
+ * If the write does not cover the whole extent, we
+ * need to calculate how we're going to split the extent.
+ * We try to do it on contig_clusters boundaries.
+ *
+ * Any extent smaller than contig_clusters will be
+ * CoWed in its entirety.
+ */
+ if (leaf_clusters <= contig_clusters)
+ *cow_len += leaf_clusters;
+ else if (*cow_len || (*cow_start == cpos)) {
+ /*
+ * This extent needs to be CoW'd from its
+ * beginning, so all we have to do is compute
+ * how many clusters to grab. We align
+ * want_clusters to the edge of contig_clusters
+ * to get better I/O.
+ */
+ want_clusters = ocfs2_cow_align_length(inode->i_sb,
+ want_clusters);
+
+ if (leaf_clusters < want_clusters)
+ *cow_len += leaf_clusters;
+ else
+ *cow_len += want_clusters;
+ } else if ((*cow_start + contig_clusters) >=
+ (cpos + write_len)) {
+ /*
+ * Breaking off contig_clusters at the front
+ * of the extent will cover our write. That's
+ * easy.
+ */
+ *cow_len = contig_clusters;
+ } else if ((rec_end - cpos) <= contig_clusters) {
+ /*
+ * Breaking off contig_clusters at the tail of
+ * this extent will cover cpos.
+ */
+ *cow_start = rec_end - contig_clusters;
+ *cow_len = contig_clusters;
+ } else if ((rec_end - cpos) <= want_clusters) {
+ /*
+ * While we can't fit the entire write in this
+ * extent, we know that the write goes from cpos
+ * to the end of the extent. Break that off.
+ * We try to break it at some multiple of
+ * contig_clusters from the front of the extent.
+ * Failing that (ie, cpos is within
+ * contig_clusters of the front), we'll CoW the
+ * entire extent.
+ */
+ *cow_start = ocfs2_cow_align_start(inode->i_sb,
+ *cow_start, cpos);
+ *cow_len = rec_end - *cow_start;
+ } else {
+ /*
+ * Ok, the entire write lives in the middle of
+ * this extent. Let's try to slice the extent up
+ * nicely. Optimally, our CoW region starts at
+ * m*contig_clusters from the beginning of the
+ * extent and goes for n*contig_clusters,
+ * covering the entire write.
+ */
+ *cow_start = ocfs2_cow_align_start(inode->i_sb,
+ *cow_start, cpos);
+
+ want_clusters = (cpos + write_len) - *cow_start;
+ want_clusters = ocfs2_cow_align_length(inode->i_sb,
+ want_clusters);
+ if (*cow_start + want_clusters <= rec_end)
+ *cow_len = want_clusters;
+ else
+ *cow_len = rec_end - *cow_start;
+ }
+
+ /* Have we covered our entire write yet? */
+ if ((*cow_start + *cow_len) >= (cpos + write_len))
+ break;
+
+ /*
+ * If we reach the end of the extent block and don't get enough
+ * clusters, continue with the next extent block if possible.
+ */
+ if (i + 1 == le16_to_cpu(el->l_next_free_rec) &&
+ eb && eb->h_next_leaf_blk) {
+ brelse(eb_bh);
+ eb_bh = NULL;
+
+ ret = ocfs2_read_extent_block(INODE_CACHE(inode),
+ le64_to_cpu(eb->h_next_leaf_blk),
+ &eb_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ eb = (struct ocfs2_extent_block *) eb_bh->b_data;
+ el = &eb->h_list;
+ i = -1;
+ }
+ }
+
+out:
+ brelse(eb_bh);
+ return ret;
+}
+
+/*
+ * Prepare meta_ac, data_ac and calculate credits when we want to add some
+ * num_clusters in data_tree "et" and change the refcount for the old
+ * clusters(starting form p_cluster) in the refcount tree.
+ *
+ * Note:
+ * 1. since we may split the old tree, so we at most will need num_clusters + 2
+ * more new leaf records.
+ * 2. In some case, we may not need to reserve new clusters(e.g, reflink), so
+ * just give data_ac = NULL.
+ */
+static int ocfs2_lock_refcount_allocators(struct super_block *sb,
+ u32 p_cluster, u32 num_clusters,
+ struct ocfs2_extent_tree *et,
+ struct ocfs2_caching_info *ref_ci,
+ struct buffer_head *ref_root_bh,
+ struct ocfs2_alloc_context **meta_ac,
+ struct ocfs2_alloc_context **data_ac,
+ int *credits)
+{
+ int ret = 0, meta_add = 0;
+ int num_free_extents = ocfs2_num_free_extents(et);
+
+ if (num_free_extents < 0) {
+ ret = num_free_extents;
+ mlog_errno(ret);
+ goto out;
+ }
+
+ if (num_free_extents < num_clusters + 2)
+ meta_add =
+ ocfs2_extend_meta_needed(et->et_root_el);
+
+ *credits += ocfs2_calc_extend_credits(sb, et->et_root_el);
+
+ ret = ocfs2_calc_refcount_meta_credits(sb, ref_ci, ref_root_bh,
+ p_cluster, num_clusters,
+ &meta_add, credits);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ trace_ocfs2_lock_refcount_allocators(meta_add, *credits);
+ ret = ocfs2_reserve_new_metadata_blocks(OCFS2_SB(sb), meta_add,
+ meta_ac);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ if (data_ac) {
+ ret = ocfs2_reserve_clusters(OCFS2_SB(sb), num_clusters,
+ data_ac);
+ if (ret)
+ mlog_errno(ret);
+ }
+
+out:
+ if (ret) {
+ if (*meta_ac) {
+ ocfs2_free_alloc_context(*meta_ac);
+ *meta_ac = NULL;
+ }
+ }
+
+ return ret;
+}
+
+static int ocfs2_clear_cow_buffer(handle_t *handle, struct buffer_head *bh)
+{
+ BUG_ON(buffer_dirty(bh));
+
+ clear_buffer_mapped(bh);
+
+ return 0;
+}
+
+int ocfs2_duplicate_clusters_by_page(handle_t *handle,
+ struct inode *inode,
+ u32 cpos, u32 old_cluster,
+ u32 new_cluster, u32 new_len)
+{
+ int ret = 0, partial;
+ struct super_block *sb = inode->i_sb;
+ u64 new_block = ocfs2_clusters_to_blocks(sb, new_cluster);
+ struct page *page;
+ pgoff_t page_index;
+ unsigned int from, to;
+ loff_t offset, end, map_end;
+ struct address_space *mapping = inode->i_mapping;
+
+ trace_ocfs2_duplicate_clusters_by_page(cpos, old_cluster,
+ new_cluster, new_len);
+
+ offset = ((loff_t)cpos) << OCFS2_SB(sb)->s_clustersize_bits;
+ end = offset + (new_len << OCFS2_SB(sb)->s_clustersize_bits);
+ /*
+ * We only duplicate pages until we reach the page contains i_size - 1.
+ * So trim 'end' to i_size.
+ */
+ if (end > i_size_read(inode))
+ end = i_size_read(inode);
+
+ while (offset < end) {
+ page_index = offset >> PAGE_SHIFT;
+ map_end = ((loff_t)page_index + 1) << PAGE_SHIFT;
+ if (map_end > end)
+ map_end = end;
+
+ /* from, to is the offset within the page. */
+ from = offset & (PAGE_SIZE - 1);
+ to = PAGE_SIZE;
+ if (map_end & (PAGE_SIZE - 1))
+ to = map_end & (PAGE_SIZE - 1);
+
+retry:
+ page = find_or_create_page(mapping, page_index, GFP_NOFS);
+ if (!page) {
+ ret = -ENOMEM;
+ mlog_errno(ret);
+ break;
+ }
+
+ /*
+ * In case PAGE_SIZE <= CLUSTER_SIZE, we do not expect a dirty
+ * page, so write it back.
+ */
+ if (PAGE_SIZE <= OCFS2_SB(sb)->s_clustersize) {
+ if (PageDirty(page)) {
+ /*
+ * write_on_page will unlock the page on return
+ */
+ ret = write_one_page(page);
+ goto retry;
+ }
+ }
+
+ if (!PageUptodate(page)) {
+ ret = block_read_full_page(page, ocfs2_get_block);
+ if (ret) {
+ mlog_errno(ret);
+ goto unlock;
+ }
+ lock_page(page);
+ }
+
+ if (page_has_buffers(page)) {
+ ret = walk_page_buffers(handle, page_buffers(page),
+ from, to, &partial,
+ ocfs2_clear_cow_buffer);
+ if (ret) {
+ mlog_errno(ret);
+ goto unlock;
+ }
+ }
+
+ ocfs2_map_and_dirty_page(inode,
+ handle, from, to,
+ page, 0, &new_block);
+ mark_page_accessed(page);
+unlock:
+ unlock_page(page);
+ put_page(page);
+ page = NULL;
+ offset = map_end;
+ if (ret)
+ break;
+ }
+
+ return ret;
+}
+
+int ocfs2_duplicate_clusters_by_jbd(handle_t *handle,
+ struct inode *inode,
+ u32 cpos, u32 old_cluster,
+ u32 new_cluster, u32 new_len)
+{
+ int ret = 0;
+ struct super_block *sb = inode->i_sb;
+ struct ocfs2_caching_info *ci = INODE_CACHE(inode);
+ int i, blocks = ocfs2_clusters_to_blocks(sb, new_len);
+ u64 old_block = ocfs2_clusters_to_blocks(sb, old_cluster);
+ u64 new_block = ocfs2_clusters_to_blocks(sb, new_cluster);
+ struct ocfs2_super *osb = OCFS2_SB(sb);
+ struct buffer_head *old_bh = NULL;
+ struct buffer_head *new_bh = NULL;
+
+ trace_ocfs2_duplicate_clusters_by_page(cpos, old_cluster,
+ new_cluster, new_len);
+
+ for (i = 0; i < blocks; i++, old_block++, new_block++) {
+ new_bh = sb_getblk(osb->sb, new_block);
+ if (new_bh == NULL) {
+ ret = -ENOMEM;
+ mlog_errno(ret);
+ break;
+ }
+
+ ocfs2_set_new_buffer_uptodate(ci, new_bh);
+
+ ret = ocfs2_read_block(ci, old_block, &old_bh, NULL);
+ if (ret) {
+ mlog_errno(ret);
+ break;
+ }
+
+ ret = ocfs2_journal_access(handle, ci, new_bh,
+ OCFS2_JOURNAL_ACCESS_CREATE);
+ if (ret) {
+ mlog_errno(ret);
+ break;
+ }
+
+ memcpy(new_bh->b_data, old_bh->b_data, sb->s_blocksize);
+ ocfs2_journal_dirty(handle, new_bh);
+
+ brelse(new_bh);
+ brelse(old_bh);
+ new_bh = NULL;
+ old_bh = NULL;
+ }
+
+ brelse(new_bh);
+ brelse(old_bh);
+ return ret;
+}
+
+static int ocfs2_clear_ext_refcount(handle_t *handle,
+ struct ocfs2_extent_tree *et,
+ u32 cpos, u32 p_cluster, u32 len,
+ unsigned int ext_flags,
+ struct ocfs2_alloc_context *meta_ac,
+ struct ocfs2_cached_dealloc_ctxt *dealloc)
+{
+ int ret, index;
+ struct ocfs2_extent_rec replace_rec;
+ struct ocfs2_path *path = NULL;
+ struct ocfs2_extent_list *el;
+ struct super_block *sb = ocfs2_metadata_cache_get_super(et->et_ci);
+ u64 ino = ocfs2_metadata_cache_owner(et->et_ci);
+
+ trace_ocfs2_clear_ext_refcount((unsigned long long)ino,
+ cpos, len, p_cluster, ext_flags);
+
+ memset(&replace_rec, 0, sizeof(replace_rec));
+ replace_rec.e_cpos = cpu_to_le32(cpos);
+ replace_rec.e_leaf_clusters = cpu_to_le16(len);
+ replace_rec.e_blkno = cpu_to_le64(ocfs2_clusters_to_blocks(sb,
+ p_cluster));
+ replace_rec.e_flags = ext_flags;
+ replace_rec.e_flags &= ~OCFS2_EXT_REFCOUNTED;
+
+ path = ocfs2_new_path_from_et(et);
+ if (!path) {
+ ret = -ENOMEM;
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_find_path(et->et_ci, path, cpos);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ el = path_leaf_el(path);
+
+ index = ocfs2_search_extent_list(el, cpos);
+ if (index == -1) {
+ ret = ocfs2_error(sb,
+ "Inode %llu has an extent at cpos %u which can no longer be found\n",
+ (unsigned long long)ino, cpos);
+ goto out;
+ }
+
+ ret = ocfs2_split_extent(handle, et, path, index,
+ &replace_rec, meta_ac, dealloc);
+ if (ret)
+ mlog_errno(ret);
+
+out:
+ ocfs2_free_path(path);
+ return ret;
+}
+
+static int ocfs2_replace_clusters(handle_t *handle,
+ struct ocfs2_cow_context *context,
+ u32 cpos, u32 old,
+ u32 new, u32 len,
+ unsigned int ext_flags)
+{
+ int ret;
+ struct ocfs2_caching_info *ci = context->data_et.et_ci;
+ u64 ino = ocfs2_metadata_cache_owner(ci);
+
+ trace_ocfs2_replace_clusters((unsigned long long)ino,
+ cpos, old, new, len, ext_flags);
+
+ /*If the old clusters is unwritten, no need to duplicate. */
+ if (!(ext_flags & OCFS2_EXT_UNWRITTEN)) {
+ ret = context->cow_duplicate_clusters(handle, context->inode,
+ cpos, old, new, len);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
+ ret = ocfs2_clear_ext_refcount(handle, &context->data_et,
+ cpos, new, len, ext_flags,
+ context->meta_ac, &context->dealloc);
+ if (ret)
+ mlog_errno(ret);
+out:
+ return ret;
+}
+
+int ocfs2_cow_sync_writeback(struct super_block *sb,
+ struct inode *inode,
+ u32 cpos, u32 num_clusters)
+{
+ int ret = 0;
+ loff_t offset, end, map_end;
+ pgoff_t page_index;
+ struct page *page;
+
+ if (ocfs2_should_order_data(inode))
+ return 0;
+
+ offset = ((loff_t)cpos) << OCFS2_SB(sb)->s_clustersize_bits;
+ end = offset + (num_clusters << OCFS2_SB(sb)->s_clustersize_bits);
+
+ ret = filemap_fdatawrite_range(inode->i_mapping,
+ offset, end - 1);
+ if (ret < 0) {
+ mlog_errno(ret);
+ return ret;
+ }
+
+ while (offset < end) {
+ page_index = offset >> PAGE_SHIFT;
+ map_end = ((loff_t)page_index + 1) << PAGE_SHIFT;
+ if (map_end > end)
+ map_end = end;
+
+ page = find_or_create_page(inode->i_mapping,
+ page_index, GFP_NOFS);
+ BUG_ON(!page);
+
+ wait_on_page_writeback(page);
+ if (PageError(page)) {
+ ret = -EIO;
+ mlog_errno(ret);
+ } else
+ mark_page_accessed(page);
+
+ unlock_page(page);
+ put_page(page);
+ page = NULL;
+ offset = map_end;
+ if (ret)
+ break;
+ }
+
+ return ret;
+}
+
+static int ocfs2_di_get_clusters(struct ocfs2_cow_context *context,
+ u32 v_cluster, u32 *p_cluster,
+ u32 *num_clusters,
+ unsigned int *extent_flags)
+{
+ return ocfs2_get_clusters(context->inode, v_cluster, p_cluster,
+ num_clusters, extent_flags);
+}
+
+static int ocfs2_make_clusters_writable(struct super_block *sb,
+ struct ocfs2_cow_context *context,
+ u32 cpos, u32 p_cluster,
+ u32 num_clusters, unsigned int e_flags)
+{
+ int ret, delete, index, credits = 0;
+ u32 new_bit, new_len, orig_num_clusters;
+ unsigned int set_len;
+ struct ocfs2_super *osb = OCFS2_SB(sb);
+ handle_t *handle;
+ struct buffer_head *ref_leaf_bh = NULL;
+ struct ocfs2_caching_info *ref_ci = &context->ref_tree->rf_ci;
+ struct ocfs2_refcount_rec rec;
+
+ trace_ocfs2_make_clusters_writable(cpos, p_cluster,
+ num_clusters, e_flags);
+
+ ret = ocfs2_lock_refcount_allocators(sb, p_cluster, num_clusters,
+ &context->data_et,
+ ref_ci,
+ context->ref_root_bh,
+ &context->meta_ac,
+ &context->data_ac, &credits);
+ if (ret) {
+ mlog_errno(ret);
+ return ret;
+ }
+
+ if (context->post_refcount)
+ credits += context->post_refcount->credits;
+
+ credits += context->extra_credits;
+ handle = ocfs2_start_trans(osb, credits);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ mlog_errno(ret);
+ goto out;
+ }
+
+ orig_num_clusters = num_clusters;
+
+ while (num_clusters) {
+ ret = ocfs2_get_refcount_rec(ref_ci, context->ref_root_bh,
+ p_cluster, num_clusters,
+ &rec, &index, &ref_leaf_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+ BUG_ON(!rec.r_refcount);
+ set_len = min((u64)p_cluster + num_clusters,
+ le64_to_cpu(rec.r_cpos) +
+ le32_to_cpu(rec.r_clusters)) - p_cluster;
+
+ /*
+ * There are many different situation here.
+ * 1. If refcount == 1, remove the flag and don't COW.
+ * 2. If refcount > 1, allocate clusters.
+ * Here we may not allocate r_len once at a time, so continue
+ * until we reach num_clusters.
+ */
+ if (le32_to_cpu(rec.r_refcount) == 1) {
+ delete = 0;
+ ret = ocfs2_clear_ext_refcount(handle,
+ &context->data_et,
+ cpos, p_cluster,
+ set_len, e_flags,
+ context->meta_ac,
+ &context->dealloc);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+ } else {
+ delete = 1;
+
+ ret = __ocfs2_claim_clusters(handle,
+ context->data_ac,
+ 1, set_len,
+ &new_bit, &new_len);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+ ret = ocfs2_replace_clusters(handle, context,
+ cpos, p_cluster, new_bit,
+ new_len, e_flags);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+ set_len = new_len;
+ }
+
+ ret = __ocfs2_decrease_refcount(handle, ref_ci,
+ context->ref_root_bh,
+ p_cluster, set_len,
+ context->meta_ac,
+ &context->dealloc, delete);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+ cpos += set_len;
+ p_cluster += set_len;
+ num_clusters -= set_len;
+ brelse(ref_leaf_bh);
+ ref_leaf_bh = NULL;
+ }
+
+ /* handle any post_cow action. */
+ if (context->post_refcount && context->post_refcount->func) {
+ ret = context->post_refcount->func(context->inode, handle,
+ context->post_refcount->para);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+ }
+
+ /*
+ * Here we should write the new page out first if we are
+ * in write-back mode.
+ */
+ if (context->get_clusters == ocfs2_di_get_clusters) {
+ ret = ocfs2_cow_sync_writeback(sb, context->inode, cpos,
+ orig_num_clusters);
+ if (ret)
+ mlog_errno(ret);
+ }
+
+out_commit:
+ ocfs2_commit_trans(osb, handle);
+
+out:
+ if (context->data_ac) {
+ ocfs2_free_alloc_context(context->data_ac);
+ context->data_ac = NULL;
+ }
+ if (context->meta_ac) {
+ ocfs2_free_alloc_context(context->meta_ac);
+ context->meta_ac = NULL;
+ }
+ brelse(ref_leaf_bh);
+
+ return ret;
+}
+
+static int ocfs2_replace_cow(struct ocfs2_cow_context *context)
+{
+ int ret = 0;
+ struct inode *inode = context->inode;
+ u32 cow_start = context->cow_start, cow_len = context->cow_len;
+ u32 p_cluster, num_clusters;
+ unsigned int ext_flags;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+
+ if (!ocfs2_refcount_tree(osb)) {
+ return ocfs2_error(inode->i_sb, "Inode %lu want to use refcount tree, but the feature bit is not set in the super block\n",
+ inode->i_ino);
+ }
+
+ ocfs2_init_dealloc_ctxt(&context->dealloc);
+
+ while (cow_len) {
+ ret = context->get_clusters(context, cow_start, &p_cluster,
+ &num_clusters, &ext_flags);
+ if (ret) {
+ mlog_errno(ret);
+ break;
+ }
+
+ BUG_ON(!(ext_flags & OCFS2_EXT_REFCOUNTED));
+
+ if (cow_len < num_clusters)
+ num_clusters = cow_len;
+
+ ret = ocfs2_make_clusters_writable(inode->i_sb, context,
+ cow_start, p_cluster,
+ num_clusters, ext_flags);
+ if (ret) {
+ mlog_errno(ret);
+ break;
+ }
+
+ cow_len -= num_clusters;
+ cow_start += num_clusters;
+ }
+
+ if (ocfs2_dealloc_has_cluster(&context->dealloc)) {
+ ocfs2_schedule_truncate_log_flush(osb, 1);
+ ocfs2_run_deallocs(osb, &context->dealloc);
+ }
+
+ return ret;
+}
+
+/*
+ * Starting at cpos, try to CoW write_len clusters. Don't CoW
+ * past max_cpos. This will stop when it runs into a hole or an
+ * unrefcounted extent.
+ */
+static int ocfs2_refcount_cow_hunk(struct inode *inode,
+ struct buffer_head *di_bh,
+ u32 cpos, u32 write_len, u32 max_cpos)
+{
+ int ret;
+ u32 cow_start = 0, cow_len = 0;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+ struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+ struct buffer_head *ref_root_bh = NULL;
+ struct ocfs2_refcount_tree *ref_tree;
+ struct ocfs2_cow_context *context = NULL;
+
+ BUG_ON(!ocfs2_is_refcount_inode(inode));
+
+ ret = ocfs2_refcount_cal_cow_clusters(inode, &di->id2.i_list,
+ cpos, write_len, max_cpos,
+ &cow_start, &cow_len);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ trace_ocfs2_refcount_cow_hunk(OCFS2_I(inode)->ip_blkno,
+ cpos, write_len, max_cpos,
+ cow_start, cow_len);
+
+ BUG_ON(cow_len == 0);
+
+ context = kzalloc(sizeof(struct ocfs2_cow_context), GFP_NOFS);
+ if (!context) {
+ ret = -ENOMEM;
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_lock_refcount_tree(osb, le64_to_cpu(di->i_refcount_loc),
+ 1, &ref_tree, &ref_root_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ context->inode = inode;
+ context->cow_start = cow_start;
+ context->cow_len = cow_len;
+ context->ref_tree = ref_tree;
+ context->ref_root_bh = ref_root_bh;
+ context->cow_duplicate_clusters = ocfs2_duplicate_clusters_by_page;
+ context->get_clusters = ocfs2_di_get_clusters;
+
+ ocfs2_init_dinode_extent_tree(&context->data_et,
+ INODE_CACHE(inode), di_bh);
+
+ ret = ocfs2_replace_cow(context);
+ if (ret)
+ mlog_errno(ret);
+
+ /*
+ * truncate the extent map here since no matter whether we meet with
+ * any error during the action, we shouldn't trust cached extent map
+ * any more.
+ */
+ ocfs2_extent_map_trunc(inode, cow_start);
+
+ ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
+ brelse(ref_root_bh);
+out:
+ kfree(context);
+ return ret;
+}
+
+/*
+ * CoW any and all clusters between cpos and cpos+write_len.
+ * Don't CoW past max_cpos. If this returns successfully, all
+ * clusters between cpos and cpos+write_len are safe to modify.
+ */
+int ocfs2_refcount_cow(struct inode *inode,
+ struct buffer_head *di_bh,
+ u32 cpos, u32 write_len, u32 max_cpos)
+{
+ int ret = 0;
+ u32 p_cluster, num_clusters;
+ unsigned int ext_flags;
+
+ while (write_len) {
+ ret = ocfs2_get_clusters(inode, cpos, &p_cluster,
+ &num_clusters, &ext_flags);
+ if (ret) {
+ mlog_errno(ret);
+ break;
+ }
+
+ if (write_len < num_clusters)
+ num_clusters = write_len;
+
+ if (ext_flags & OCFS2_EXT_REFCOUNTED) {
+ ret = ocfs2_refcount_cow_hunk(inode, di_bh, cpos,
+ num_clusters, max_cpos);
+ if (ret) {
+ mlog_errno(ret);
+ break;
+ }
+ }
+
+ write_len -= num_clusters;
+ cpos += num_clusters;
+ }
+
+ return ret;
+}
+
+static int ocfs2_xattr_value_get_clusters(struct ocfs2_cow_context *context,
+ u32 v_cluster, u32 *p_cluster,
+ u32 *num_clusters,
+ unsigned int *extent_flags)
+{
+ struct inode *inode = context->inode;
+ struct ocfs2_xattr_value_root *xv = context->cow_object;
+
+ return ocfs2_xattr_get_clusters(inode, v_cluster, p_cluster,
+ num_clusters, &xv->xr_list,
+ extent_flags);
+}
+
+/*
+ * Given a xattr value root, calculate the most meta/credits we need for
+ * refcount tree change if we truncate it to 0.
+ */
+int ocfs2_refcounted_xattr_delete_need(struct inode *inode,
+ struct ocfs2_caching_info *ref_ci,
+ struct buffer_head *ref_root_bh,
+ struct ocfs2_xattr_value_root *xv,
+ int *meta_add, int *credits)
+{
+ int ret = 0, index, ref_blocks = 0;
+ u32 p_cluster, num_clusters;
+ u32 cpos = 0, clusters = le32_to_cpu(xv->xr_clusters);
+ struct ocfs2_refcount_block *rb;
+ struct ocfs2_refcount_rec rec;
+ struct buffer_head *ref_leaf_bh = NULL;
+
+ while (cpos < clusters) {
+ ret = ocfs2_xattr_get_clusters(inode, cpos, &p_cluster,
+ &num_clusters, &xv->xr_list,
+ NULL);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ cpos += num_clusters;
+
+ while (num_clusters) {
+ ret = ocfs2_get_refcount_rec(ref_ci, ref_root_bh,
+ p_cluster, num_clusters,
+ &rec, &index,
+ &ref_leaf_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ BUG_ON(!rec.r_refcount);
+
+ rb = (struct ocfs2_refcount_block *)ref_leaf_bh->b_data;
+
+ /*
+ * We really don't know whether the other clusters is in
+ * this refcount block or not, so just take the worst
+ * case that all the clusters are in this block and each
+ * one will split a refcount rec, so totally we need
+ * clusters * 2 new refcount rec.
+ */
+ if (le16_to_cpu(rb->rf_records.rl_used) + clusters * 2 >
+ le16_to_cpu(rb->rf_records.rl_count))
+ ref_blocks++;
+
+ *credits += 1;
+ brelse(ref_leaf_bh);
+ ref_leaf_bh = NULL;
+
+ if (num_clusters <= le32_to_cpu(rec.r_clusters))
+ break;
+ else
+ num_clusters -= le32_to_cpu(rec.r_clusters);
+ p_cluster += num_clusters;
+ }
+ }
+
+ *meta_add += ref_blocks;
+ if (!ref_blocks)
+ goto out;
+
+ rb = (struct ocfs2_refcount_block *)ref_root_bh->b_data;
+ if (le32_to_cpu(rb->rf_flags) & OCFS2_REFCOUNT_TREE_FL)
+ *credits += OCFS2_EXPAND_REFCOUNT_TREE_CREDITS;
+ else {
+ struct ocfs2_extent_tree et;
+
+ ocfs2_init_refcount_extent_tree(&et, ref_ci, ref_root_bh);
+ *credits += ocfs2_calc_extend_credits(inode->i_sb,
+ et.et_root_el);
+ }
+
+out:
+ brelse(ref_leaf_bh);
+ return ret;
+}
+
+/*
+ * Do CoW for xattr.
+ */
+int ocfs2_refcount_cow_xattr(struct inode *inode,
+ struct ocfs2_dinode *di,
+ struct ocfs2_xattr_value_buf *vb,
+ struct ocfs2_refcount_tree *ref_tree,
+ struct buffer_head *ref_root_bh,
+ u32 cpos, u32 write_len,
+ struct ocfs2_post_refcount *post)
+{
+ int ret;
+ struct ocfs2_xattr_value_root *xv = vb->vb_xv;
+ struct ocfs2_cow_context *context = NULL;
+ u32 cow_start, cow_len;
+
+ BUG_ON(!ocfs2_is_refcount_inode(inode));
+
+ ret = ocfs2_refcount_cal_cow_clusters(inode, &xv->xr_list,
+ cpos, write_len, UINT_MAX,
+ &cow_start, &cow_len);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ BUG_ON(cow_len == 0);
+
+ context = kzalloc(sizeof(struct ocfs2_cow_context), GFP_NOFS);
+ if (!context) {
+ ret = -ENOMEM;
+ mlog_errno(ret);
+ goto out;
+ }
+
+ context->inode = inode;
+ context->cow_start = cow_start;
+ context->cow_len = cow_len;
+ context->ref_tree = ref_tree;
+ context->ref_root_bh = ref_root_bh;
+ context->cow_object = xv;
+
+ context->cow_duplicate_clusters = ocfs2_duplicate_clusters_by_jbd;
+ /* We need the extra credits for duplicate_clusters by jbd. */
+ context->extra_credits =
+ ocfs2_clusters_to_blocks(inode->i_sb, 1) * cow_len;
+ context->get_clusters = ocfs2_xattr_value_get_clusters;
+ context->post_refcount = post;
+
+ ocfs2_init_xattr_value_extent_tree(&context->data_et,
+ INODE_CACHE(inode), vb);
+
+ ret = ocfs2_replace_cow(context);
+ if (ret)
+ mlog_errno(ret);
+
+out:
+ kfree(context);
+ return ret;
+}
+
+/*
+ * Insert a new extent into refcount tree and mark a extent rec
+ * as refcounted in the dinode tree.
+ */
+int ocfs2_add_refcount_flag(struct inode *inode,
+ struct ocfs2_extent_tree *data_et,
+ struct ocfs2_caching_info *ref_ci,
+ struct buffer_head *ref_root_bh,
+ u32 cpos, u32 p_cluster, u32 num_clusters,
+ struct ocfs2_cached_dealloc_ctxt *dealloc,
+ struct ocfs2_post_refcount *post)
+{
+ int ret;
+ handle_t *handle;
+ int credits = 1, ref_blocks = 0;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+ struct ocfs2_alloc_context *meta_ac = NULL;
+
+ /* We need to be able to handle at least an extent tree split. */
+ ref_blocks = ocfs2_extend_meta_needed(data_et->et_root_el);
+
+ ret = ocfs2_calc_refcount_meta_credits(inode->i_sb,
+ ref_ci, ref_root_bh,
+ p_cluster, num_clusters,
+ &ref_blocks, &credits);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ trace_ocfs2_add_refcount_flag(ref_blocks, credits);
+
+ if (ref_blocks) {
+ ret = ocfs2_reserve_new_metadata_blocks(osb,
+ ref_blocks, &meta_ac);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
+ if (post)
+ credits += post->credits;
+
+ handle = ocfs2_start_trans(osb, credits);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_mark_extent_refcounted(inode, data_et, handle,
+ cpos, num_clusters, p_cluster,
+ meta_ac, dealloc);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+ ret = __ocfs2_increase_refcount(handle, ref_ci, ref_root_bh,
+ p_cluster, num_clusters, 0,
+ meta_ac, dealloc);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+ if (post && post->func) {
+ ret = post->func(inode, handle, post->para);
+ if (ret)
+ mlog_errno(ret);
+ }
+
+out_commit:
+ ocfs2_commit_trans(osb, handle);
+out:
+ if (meta_ac)
+ ocfs2_free_alloc_context(meta_ac);
+ return ret;
+}
+
+static int ocfs2_change_ctime(struct inode *inode,
+ struct buffer_head *di_bh)
+{
+ int ret;
+ handle_t *handle;
+ struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+
+ handle = ocfs2_start_trans(OCFS2_SB(inode->i_sb),
+ OCFS2_INODE_UPDATE_CREDITS);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+ inode->i_ctime = current_time(inode);
+ di->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec);
+ di->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
+
+ ocfs2_journal_dirty(handle, di_bh);
+
+out_commit:
+ ocfs2_commit_trans(OCFS2_SB(inode->i_sb), handle);
+out:
+ return ret;
+}
+
+static int ocfs2_attach_refcount_tree(struct inode *inode,
+ struct buffer_head *di_bh)
+{
+ int ret, data_changed = 0;
+ struct buffer_head *ref_root_bh = NULL;
+ struct ocfs2_inode_info *oi = OCFS2_I(inode);
+ struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+ struct ocfs2_refcount_tree *ref_tree;
+ unsigned int ext_flags;
+ loff_t size;
+ u32 cpos, num_clusters, clusters, p_cluster;
+ struct ocfs2_cached_dealloc_ctxt dealloc;
+ struct ocfs2_extent_tree di_et;
+
+ ocfs2_init_dealloc_ctxt(&dealloc);
+
+ if (!ocfs2_is_refcount_inode(inode)) {
+ ret = ocfs2_create_refcount_tree(inode, di_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
+ BUG_ON(!di->i_refcount_loc);
+ ret = ocfs2_lock_refcount_tree(osb,
+ le64_to_cpu(di->i_refcount_loc), 1,
+ &ref_tree, &ref_root_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ if (oi->ip_dyn_features & OCFS2_INLINE_DATA_FL)
+ goto attach_xattr;
+
+ ocfs2_init_dinode_extent_tree(&di_et, INODE_CACHE(inode), di_bh);
+
+ size = i_size_read(inode);
+ clusters = ocfs2_clusters_for_bytes(inode->i_sb, size);
+
+ cpos = 0;
+ while (cpos < clusters) {
+ ret = ocfs2_get_clusters(inode, cpos, &p_cluster,
+ &num_clusters, &ext_flags);
+ if (ret) {
+ mlog_errno(ret);
+ goto unlock;
+ }
+ if (p_cluster && !(ext_flags & OCFS2_EXT_REFCOUNTED)) {
+ ret = ocfs2_add_refcount_flag(inode, &di_et,
+ &ref_tree->rf_ci,
+ ref_root_bh, cpos,
+ p_cluster, num_clusters,
+ &dealloc, NULL);
+ if (ret) {
+ mlog_errno(ret);
+ goto unlock;
+ }
+
+ data_changed = 1;
+ }
+ cpos += num_clusters;
+ }
+
+attach_xattr:
+ if (oi->ip_dyn_features & OCFS2_HAS_XATTR_FL) {
+ ret = ocfs2_xattr_attach_refcount_tree(inode, di_bh,
+ &ref_tree->rf_ci,
+ ref_root_bh,
+ &dealloc);
+ if (ret) {
+ mlog_errno(ret);
+ goto unlock;
+ }
+ }
+
+ if (data_changed) {
+ ret = ocfs2_change_ctime(inode, di_bh);
+ if (ret)
+ mlog_errno(ret);
+ }
+
+unlock:
+ ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
+ brelse(ref_root_bh);
+
+ if (!ret && ocfs2_dealloc_has_cluster(&dealloc)) {
+ ocfs2_schedule_truncate_log_flush(osb, 1);
+ ocfs2_run_deallocs(osb, &dealloc);
+ }
+out:
+ /*
+ * Empty the extent map so that we may get the right extent
+ * record from the disk.
+ */
+ ocfs2_extent_map_trunc(inode, 0);
+
+ return ret;
+}
+
+static int ocfs2_add_refcounted_extent(struct inode *inode,
+ struct ocfs2_extent_tree *et,
+ struct ocfs2_caching_info *ref_ci,
+ struct buffer_head *ref_root_bh,
+ u32 cpos, u32 p_cluster, u32 num_clusters,
+ unsigned int ext_flags,
+ struct ocfs2_cached_dealloc_ctxt *dealloc)
+{
+ int ret;
+ handle_t *handle;
+ int credits = 0;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+ struct ocfs2_alloc_context *meta_ac = NULL;
+
+ ret = ocfs2_lock_refcount_allocators(inode->i_sb,
+ p_cluster, num_clusters,
+ et, ref_ci,
+ ref_root_bh, &meta_ac,
+ NULL, &credits);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ handle = ocfs2_start_trans(osb, credits);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_insert_extent(handle, et, cpos,
+ ocfs2_clusters_to_blocks(inode->i_sb, p_cluster),
+ num_clusters, ext_flags, meta_ac);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+ ret = ocfs2_increase_refcount(handle, ref_ci, ref_root_bh,
+ p_cluster, num_clusters,
+ meta_ac, dealloc);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+ ret = dquot_alloc_space_nodirty(inode,
+ ocfs2_clusters_to_bytes(osb->sb, num_clusters));
+ if (ret)
+ mlog_errno(ret);
+
+out_commit:
+ ocfs2_commit_trans(osb, handle);
+out:
+ if (meta_ac)
+ ocfs2_free_alloc_context(meta_ac);
+ return ret;
+}
+
+static int ocfs2_duplicate_inline_data(struct inode *s_inode,
+ struct buffer_head *s_bh,
+ struct inode *t_inode,
+ struct buffer_head *t_bh)
+{
+ int ret;
+ handle_t *handle;
+ struct ocfs2_super *osb = OCFS2_SB(s_inode->i_sb);
+ struct ocfs2_dinode *s_di = (struct ocfs2_dinode *)s_bh->b_data;
+ struct ocfs2_dinode *t_di = (struct ocfs2_dinode *)t_bh->b_data;
+
+ BUG_ON(!(OCFS2_I(s_inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL));
+
+ handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_journal_access_di(handle, INODE_CACHE(t_inode), t_bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+ t_di->id2.i_data.id_count = s_di->id2.i_data.id_count;
+ memcpy(t_di->id2.i_data.id_data, s_di->id2.i_data.id_data,
+ le16_to_cpu(s_di->id2.i_data.id_count));
+ spin_lock(&OCFS2_I(t_inode)->ip_lock);
+ OCFS2_I(t_inode)->ip_dyn_features |= OCFS2_INLINE_DATA_FL;
+ t_di->i_dyn_features = cpu_to_le16(OCFS2_I(t_inode)->ip_dyn_features);
+ spin_unlock(&OCFS2_I(t_inode)->ip_lock);
+
+ ocfs2_journal_dirty(handle, t_bh);
+
+out_commit:
+ ocfs2_commit_trans(osb, handle);
+out:
+ return ret;
+}
+
+static int ocfs2_duplicate_extent_list(struct inode *s_inode,
+ struct inode *t_inode,
+ struct buffer_head *t_bh,
+ struct ocfs2_caching_info *ref_ci,
+ struct buffer_head *ref_root_bh,
+ struct ocfs2_cached_dealloc_ctxt *dealloc)
+{
+ int ret = 0;
+ u32 p_cluster, num_clusters, clusters, cpos;
+ loff_t size;
+ unsigned int ext_flags;
+ struct ocfs2_extent_tree et;
+
+ ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(t_inode), t_bh);
+
+ size = i_size_read(s_inode);
+ clusters = ocfs2_clusters_for_bytes(s_inode->i_sb, size);
+
+ cpos = 0;
+ while (cpos < clusters) {
+ ret = ocfs2_get_clusters(s_inode, cpos, &p_cluster,
+ &num_clusters, &ext_flags);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ if (p_cluster) {
+ ret = ocfs2_add_refcounted_extent(t_inode, &et,
+ ref_ci, ref_root_bh,
+ cpos, p_cluster,
+ num_clusters,
+ ext_flags,
+ dealloc);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
+ cpos += num_clusters;
+ }
+
+out:
+ return ret;
+}
+
+/*
+ * change the new file's attributes to the src.
+ *
+ * reflink creates a snapshot of a file, that means the attributes
+ * must be identical except for three exceptions - nlink, ino, and ctime.
+ */
+static int ocfs2_complete_reflink(struct inode *s_inode,
+ struct buffer_head *s_bh,
+ struct inode *t_inode,
+ struct buffer_head *t_bh,
+ bool preserve)
+{
+ int ret;
+ handle_t *handle;
+ struct ocfs2_dinode *s_di = (struct ocfs2_dinode *)s_bh->b_data;
+ struct ocfs2_dinode *di = (struct ocfs2_dinode *)t_bh->b_data;
+ loff_t size = i_size_read(s_inode);
+
+ handle = ocfs2_start_trans(OCFS2_SB(t_inode->i_sb),
+ OCFS2_INODE_UPDATE_CREDITS);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ mlog_errno(ret);
+ return ret;
+ }
+
+ ret = ocfs2_journal_access_di(handle, INODE_CACHE(t_inode), t_bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+ spin_lock(&OCFS2_I(t_inode)->ip_lock);
+ OCFS2_I(t_inode)->ip_clusters = OCFS2_I(s_inode)->ip_clusters;
+ OCFS2_I(t_inode)->ip_attr = OCFS2_I(s_inode)->ip_attr;
+ OCFS2_I(t_inode)->ip_dyn_features = OCFS2_I(s_inode)->ip_dyn_features;
+ spin_unlock(&OCFS2_I(t_inode)->ip_lock);
+ i_size_write(t_inode, size);
+ t_inode->i_blocks = s_inode->i_blocks;
+
+ di->i_xattr_inline_size = s_di->i_xattr_inline_size;
+ di->i_clusters = s_di->i_clusters;
+ di->i_size = s_di->i_size;
+ di->i_dyn_features = s_di->i_dyn_features;
+ di->i_attr = s_di->i_attr;
+
+ if (preserve) {
+ t_inode->i_uid = s_inode->i_uid;
+ t_inode->i_gid = s_inode->i_gid;
+ t_inode->i_mode = s_inode->i_mode;
+ di->i_uid = s_di->i_uid;
+ di->i_gid = s_di->i_gid;
+ di->i_mode = s_di->i_mode;
+
+ /*
+ * update time.
+ * we want mtime to appear identical to the source and
+ * update ctime.
+ */
+ t_inode->i_ctime = current_time(t_inode);
+
+ di->i_ctime = cpu_to_le64(t_inode->i_ctime.tv_sec);
+ di->i_ctime_nsec = cpu_to_le32(t_inode->i_ctime.tv_nsec);
+
+ t_inode->i_mtime = s_inode->i_mtime;
+ di->i_mtime = s_di->i_mtime;
+ di->i_mtime_nsec = s_di->i_mtime_nsec;
+ }
+
+ ocfs2_journal_dirty(handle, t_bh);
+
+out_commit:
+ ocfs2_commit_trans(OCFS2_SB(t_inode->i_sb), handle);
+ return ret;
+}
+
+static int ocfs2_create_reflink_node(struct inode *s_inode,
+ struct buffer_head *s_bh,
+ struct inode *t_inode,
+ struct buffer_head *t_bh,
+ bool preserve)
+{
+ int ret;
+ struct buffer_head *ref_root_bh = NULL;
+ struct ocfs2_cached_dealloc_ctxt dealloc;
+ struct ocfs2_super *osb = OCFS2_SB(s_inode->i_sb);
+ struct ocfs2_refcount_block *rb;
+ struct ocfs2_dinode *di = (struct ocfs2_dinode *)s_bh->b_data;
+ struct ocfs2_refcount_tree *ref_tree;
+
+ ocfs2_init_dealloc_ctxt(&dealloc);
+
+ ret = ocfs2_set_refcount_tree(t_inode, t_bh,
+ le64_to_cpu(di->i_refcount_loc));
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ if (OCFS2_I(s_inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
+ ret = ocfs2_duplicate_inline_data(s_inode, s_bh,
+ t_inode, t_bh);
+ if (ret)
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_lock_refcount_tree(osb, le64_to_cpu(di->i_refcount_loc),
+ 1, &ref_tree, &ref_root_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ rb = (struct ocfs2_refcount_block *)ref_root_bh->b_data;
+
+ ret = ocfs2_duplicate_extent_list(s_inode, t_inode, t_bh,
+ &ref_tree->rf_ci, ref_root_bh,
+ &dealloc);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_unlock_refcount;
+ }
+
+out_unlock_refcount:
+ ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
+ brelse(ref_root_bh);
+out:
+ if (ocfs2_dealloc_has_cluster(&dealloc)) {
+ ocfs2_schedule_truncate_log_flush(osb, 1);
+ ocfs2_run_deallocs(osb, &dealloc);
+ }
+
+ return ret;
+}
+
+static int __ocfs2_reflink(struct dentry *old_dentry,
+ struct buffer_head *old_bh,
+ struct inode *new_inode,
+ bool preserve)
+{
+ int ret;
+ struct inode *inode = d_inode(old_dentry);
+ struct buffer_head *new_bh = NULL;
+
+ if (OCFS2_I(inode)->ip_flags & OCFS2_INODE_SYSTEM_FILE) {
+ ret = -EINVAL;
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = filemap_fdatawrite(inode->i_mapping);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_attach_refcount_tree(inode, old_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ inode_lock_nested(new_inode, I_MUTEX_CHILD);
+ ret = ocfs2_inode_lock_nested(new_inode, &new_bh, 1,
+ OI_LS_REFLINK_TARGET);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_unlock;
+ }
+
+ ret = ocfs2_create_reflink_node(inode, old_bh,
+ new_inode, new_bh, preserve);
+ if (ret) {
+ mlog_errno(ret);
+ goto inode_unlock;
+ }
+
+ if (OCFS2_I(inode)->ip_dyn_features & OCFS2_HAS_XATTR_FL) {
+ ret = ocfs2_reflink_xattrs(inode, old_bh,
+ new_inode, new_bh,
+ preserve);
+ if (ret) {
+ mlog_errno(ret);
+ goto inode_unlock;
+ }
+ }
+
+ ret = ocfs2_complete_reflink(inode, old_bh,
+ new_inode, new_bh, preserve);
+ if (ret)
+ mlog_errno(ret);
+
+inode_unlock:
+ ocfs2_inode_unlock(new_inode, 1);
+ brelse(new_bh);
+out_unlock:
+ inode_unlock(new_inode);
+out:
+ if (!ret) {
+ ret = filemap_fdatawait(inode->i_mapping);
+ if (ret)
+ mlog_errno(ret);
+ }
+ return ret;
+}
+
+static int ocfs2_reflink(struct dentry *old_dentry, struct inode *dir,
+ struct dentry *new_dentry, bool preserve)
+{
+ int error, had_lock;
+ struct inode *inode = d_inode(old_dentry);
+ struct buffer_head *old_bh = NULL;
+ struct inode *new_orphan_inode = NULL;
+ struct ocfs2_lock_holder oh;
+
+ if (!ocfs2_refcount_tree(OCFS2_SB(inode->i_sb)))
+ return -EOPNOTSUPP;
+
+
+ error = ocfs2_create_inode_in_orphan(dir, inode->i_mode,
+ &new_orphan_inode);
+ if (error) {
+ mlog_errno(error);
+ goto out;
+ }
+
+ error = ocfs2_rw_lock(inode, 1);
+ if (error) {
+ mlog_errno(error);
+ goto out;
+ }
+
+ error = ocfs2_inode_lock(inode, &old_bh, 1);
+ if (error) {
+ mlog_errno(error);
+ ocfs2_rw_unlock(inode, 1);
+ goto out;
+ }
+
+ down_write(&OCFS2_I(inode)->ip_xattr_sem);
+ down_write(&OCFS2_I(inode)->ip_alloc_sem);
+ error = __ocfs2_reflink(old_dentry, old_bh,
+ new_orphan_inode, preserve);
+ up_write(&OCFS2_I(inode)->ip_alloc_sem);
+ up_write(&OCFS2_I(inode)->ip_xattr_sem);
+
+ ocfs2_inode_unlock(inode, 1);
+ ocfs2_rw_unlock(inode, 1);
+ brelse(old_bh);
+
+ if (error) {
+ mlog_errno(error);
+ goto out;
+ }
+
+ had_lock = ocfs2_inode_lock_tracker(new_orphan_inode, NULL, 1,
+ &oh);
+ if (had_lock < 0) {
+ error = had_lock;
+ mlog_errno(error);
+ goto out;
+ }
+
+ /* If the security isn't preserved, we need to re-initialize them. */
+ if (!preserve) {
+ error = ocfs2_init_security_and_acl(dir, new_orphan_inode,
+ &new_dentry->d_name);
+ if (error)
+ mlog_errno(error);
+ }
+ if (!error) {
+ error = ocfs2_mv_orphaned_inode_to_new(dir, new_orphan_inode,
+ new_dentry);
+ if (error)
+ mlog_errno(error);
+ }
+ ocfs2_inode_unlock_tracker(new_orphan_inode, 1, &oh, had_lock);
+
+out:
+ if (new_orphan_inode) {
+ /*
+ * We need to open_unlock the inode no matter whether we
+ * succeed or not, so that other nodes can delete it later.
+ */
+ ocfs2_open_unlock(new_orphan_inode);
+ if (error)
+ iput(new_orphan_inode);
+ }
+
+ return error;
+}
+
+/*
+ * Below here are the bits used by OCFS2_IOC_REFLINK() to fake
+ * sys_reflink(). This will go away when vfs_reflink() exists in
+ * fs/namei.c.
+ */
+
+/* copied from may_create in VFS. */
+static inline int ocfs2_may_create(struct inode *dir, struct dentry *child)
+{
+ if (d_really_is_positive(child))
+ return -EEXIST;
+ if (IS_DEADDIR(dir))
+ return -ENOENT;
+ return inode_permission(dir, MAY_WRITE | MAY_EXEC);
+}
+
+/**
+ * ocfs2_vfs_reflink - Create a reference-counted link
+ *
+ * @old_dentry: source dentry + inode
+ * @dir: directory to create the target
+ * @new_dentry: target dentry
+ * @preserve: if true, preserve all file attributes
+ */
+static int ocfs2_vfs_reflink(struct dentry *old_dentry, struct inode *dir,
+ struct dentry *new_dentry, bool preserve)
+{
+ struct inode *inode = d_inode(old_dentry);
+ int error;
+
+ if (!inode)
+ return -ENOENT;
+
+ error = ocfs2_may_create(dir, new_dentry);
+ if (error)
+ return error;
+
+ if (dir->i_sb != inode->i_sb)
+ return -EXDEV;
+
+ /*
+ * A reflink to an append-only or immutable file cannot be created.
+ */
+ if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
+ return -EPERM;
+
+ /* Only regular files can be reflinked. */
+ if (!S_ISREG(inode->i_mode))
+ return -EPERM;
+
+ /*
+ * If the caller wants to preserve ownership, they require the
+ * rights to do so.
+ */
+ if (preserve) {
+ if (!uid_eq(current_fsuid(), inode->i_uid) && !capable(CAP_CHOWN))
+ return -EPERM;
+ if (!in_group_p(inode->i_gid) && !capable(CAP_CHOWN))
+ return -EPERM;
+ }
+
+ /*
+ * If the caller is modifying any aspect of the attributes, they
+ * are not creating a snapshot. They need read permission on the
+ * file.
+ */
+ if (!preserve) {
+ error = inode_permission(inode, MAY_READ);
+ if (error)
+ return error;
+ }
+
+ inode_lock(inode);
+ error = dquot_initialize(dir);
+ if (!error)
+ error = ocfs2_reflink(old_dentry, dir, new_dentry, preserve);
+ inode_unlock(inode);
+ if (!error)
+ fsnotify_create(dir, new_dentry);
+ return error;
+}
+/*
+ * Most codes are copied from sys_linkat.
+ */
+int ocfs2_reflink_ioctl(struct inode *inode,
+ const char __user *oldname,
+ const char __user *newname,
+ bool preserve)
+{
+ struct dentry *new_dentry;
+ struct path old_path, new_path;
+ int error;
+
+ if (!ocfs2_refcount_tree(OCFS2_SB(inode->i_sb)))
+ return -EOPNOTSUPP;
+
+ error = user_path_at(AT_FDCWD, oldname, 0, &old_path);
+ if (error) {
+ mlog_errno(error);
+ return error;
+ }
+
+ new_dentry = user_path_create(AT_FDCWD, newname, &new_path, 0);
+ error = PTR_ERR(new_dentry);
+ if (IS_ERR(new_dentry)) {
+ mlog_errno(error);
+ goto out;
+ }
+
+ error = -EXDEV;
+ if (old_path.mnt != new_path.mnt) {
+ mlog_errno(error);
+ goto out_dput;
+ }
+
+ error = ocfs2_vfs_reflink(old_path.dentry,
+ d_inode(new_path.dentry),
+ new_dentry, preserve);
+out_dput:
+ done_path_create(&new_path, new_dentry);
+out:
+ path_put(&old_path);
+
+ return error;
+}
+
+/* Update destination inode size, if necessary. */
+static int ocfs2_reflink_update_dest(struct inode *dest,
+ struct buffer_head *d_bh,
+ loff_t newlen)
+{
+ handle_t *handle;
+ int ret;
+
+ dest->i_blocks = ocfs2_inode_sector_count(dest);
+
+ if (newlen <= i_size_read(dest))
+ return 0;
+
+ handle = ocfs2_start_trans(OCFS2_SB(dest->i_sb),
+ OCFS2_INODE_UPDATE_CREDITS);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ mlog_errno(ret);
+ return ret;
+ }
+
+ /* Extend i_size if needed. */
+ spin_lock(&OCFS2_I(dest)->ip_lock);
+ if (newlen > i_size_read(dest))
+ i_size_write(dest, newlen);
+ spin_unlock(&OCFS2_I(dest)->ip_lock);
+ dest->i_ctime = dest->i_mtime = current_time(dest);
+
+ ret = ocfs2_mark_inode_dirty(handle, dest, d_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+out_commit:
+ ocfs2_commit_trans(OCFS2_SB(dest->i_sb), handle);
+ return ret;
+}
+
+/* Remap the range pos_in:len in s_inode to pos_out:len in t_inode. */
+static int ocfs2_reflink_remap_extent(struct inode *s_inode,
+ struct buffer_head *s_bh,
+ loff_t pos_in,
+ struct inode *t_inode,
+ struct buffer_head *t_bh,
+ loff_t pos_out,
+ loff_t len,
+ struct ocfs2_cached_dealloc_ctxt *dealloc)
+{
+ struct ocfs2_extent_tree s_et;
+ struct ocfs2_extent_tree t_et;
+ struct ocfs2_dinode *dis;
+ struct buffer_head *ref_root_bh = NULL;
+ struct ocfs2_refcount_tree *ref_tree;
+ struct ocfs2_super *osb;
+ loff_t pstart, plen;
+ u32 p_cluster, num_clusters, slast, spos, tpos;
+ unsigned int ext_flags;
+ int ret = 0;
+
+ osb = OCFS2_SB(s_inode->i_sb);
+ dis = (struct ocfs2_dinode *)s_bh->b_data;
+ ocfs2_init_dinode_extent_tree(&s_et, INODE_CACHE(s_inode), s_bh);
+ ocfs2_init_dinode_extent_tree(&t_et, INODE_CACHE(t_inode), t_bh);
+
+ spos = ocfs2_bytes_to_clusters(s_inode->i_sb, pos_in);
+ tpos = ocfs2_bytes_to_clusters(t_inode->i_sb, pos_out);
+ slast = ocfs2_clusters_for_bytes(s_inode->i_sb, pos_in + len);
+
+ while (spos < slast) {
+ if (fatal_signal_pending(current)) {
+ ret = -EINTR;
+ goto out;
+ }
+
+ /* Look up the extent. */
+ ret = ocfs2_get_clusters(s_inode, spos, &p_cluster,
+ &num_clusters, &ext_flags);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ num_clusters = min_t(u32, num_clusters, slast - spos);
+
+ /* Punch out the dest range. */
+ pstart = ocfs2_clusters_to_bytes(t_inode->i_sb, tpos);
+ plen = ocfs2_clusters_to_bytes(t_inode->i_sb, num_clusters);
+ ret = ocfs2_remove_inode_range(t_inode, t_bh, pstart, plen);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ if (p_cluster == 0)
+ goto next_loop;
+
+ /* Lock the refcount btree... */
+ ret = ocfs2_lock_refcount_tree(osb,
+ le64_to_cpu(dis->i_refcount_loc),
+ 1, &ref_tree, &ref_root_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ /* Mark s_inode's extent as refcounted. */
+ if (!(ext_flags & OCFS2_EXT_REFCOUNTED)) {
+ ret = ocfs2_add_refcount_flag(s_inode, &s_et,
+ &ref_tree->rf_ci,
+ ref_root_bh, spos,
+ p_cluster, num_clusters,
+ dealloc, NULL);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_unlock_refcount;
+ }
+ }
+
+ /* Map in the new extent. */
+ ext_flags |= OCFS2_EXT_REFCOUNTED;
+ ret = ocfs2_add_refcounted_extent(t_inode, &t_et,
+ &ref_tree->rf_ci,
+ ref_root_bh,
+ tpos, p_cluster,
+ num_clusters,
+ ext_flags,
+ dealloc);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_unlock_refcount;
+ }
+
+ ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
+ brelse(ref_root_bh);
+next_loop:
+ spos += num_clusters;
+ tpos += num_clusters;
+ }
+
+out:
+ return ret;
+out_unlock_refcount:
+ ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
+ brelse(ref_root_bh);
+ return ret;
+}
+
+/* Set up refcount tree and remap s_inode to t_inode. */
+static int ocfs2_reflink_remap_blocks(struct inode *s_inode,
+ struct buffer_head *s_bh,
+ loff_t pos_in,
+ struct inode *t_inode,
+ struct buffer_head *t_bh,
+ loff_t pos_out,
+ loff_t len)
+{
+ struct ocfs2_cached_dealloc_ctxt dealloc;
+ struct ocfs2_super *osb;
+ struct ocfs2_dinode *dis;
+ struct ocfs2_dinode *dit;
+ int ret;
+
+ osb = OCFS2_SB(s_inode->i_sb);
+ dis = (struct ocfs2_dinode *)s_bh->b_data;
+ dit = (struct ocfs2_dinode *)t_bh->b_data;
+ ocfs2_init_dealloc_ctxt(&dealloc);
+
+ /*
+ * If we're reflinking the entire file and the source is inline
+ * data, just copy the contents.
+ */
+ if (pos_in == pos_out && pos_in == 0 && len == i_size_read(s_inode) &&
+ i_size_read(t_inode) <= len &&
+ (OCFS2_I(s_inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)) {
+ ret = ocfs2_duplicate_inline_data(s_inode, s_bh, t_inode, t_bh);
+ if (ret)
+ mlog_errno(ret);
+ goto out;
+ }
+
+ /*
+ * If both inodes belong to two different refcount groups then
+ * forget it because we don't know how (or want) to go merging
+ * refcount trees.
+ */
+ ret = -EOPNOTSUPP;
+ if (ocfs2_is_refcount_inode(s_inode) &&
+ ocfs2_is_refcount_inode(t_inode) &&
+ le64_to_cpu(dis->i_refcount_loc) !=
+ le64_to_cpu(dit->i_refcount_loc))
+ goto out;
+
+ /* Neither inode has a refcount tree. Add one to s_inode. */
+ if (!ocfs2_is_refcount_inode(s_inode) &&
+ !ocfs2_is_refcount_inode(t_inode)) {
+ ret = ocfs2_create_refcount_tree(s_inode, s_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
+ /* Ensure that both inodes end up with the same refcount tree. */
+ if (!ocfs2_is_refcount_inode(s_inode)) {
+ ret = ocfs2_set_refcount_tree(s_inode, s_bh,
+ le64_to_cpu(dit->i_refcount_loc));
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+ if (!ocfs2_is_refcount_inode(t_inode)) {
+ ret = ocfs2_set_refcount_tree(t_inode, t_bh,
+ le64_to_cpu(dis->i_refcount_loc));
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
+ /* Turn off inline data in the dest file. */
+ if (OCFS2_I(t_inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
+ ret = ocfs2_convert_inline_data_to_extents(t_inode, t_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
+ /* Actually remap extents now. */
+ ret = ocfs2_reflink_remap_extent(s_inode, s_bh, pos_in, t_inode, t_bh,
+ pos_out, len, &dealloc);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+out:
+ if (ocfs2_dealloc_has_cluster(&dealloc)) {
+ ocfs2_schedule_truncate_log_flush(osb, 1);
+ ocfs2_run_deallocs(osb, &dealloc);
+ }
+
+ return ret;
+}
+
+/* Lock an inode and grab a bh pointing to the inode. */
+static int ocfs2_reflink_inodes_lock(struct inode *s_inode,
+ struct buffer_head **bh1,
+ struct inode *t_inode,
+ struct buffer_head **bh2)
+{
+ struct inode *inode1;
+ struct inode *inode2;
+ struct ocfs2_inode_info *oi1;
+ struct ocfs2_inode_info *oi2;
+ bool same_inode = (s_inode == t_inode);
+ int status;
+
+ /* First grab the VFS and rw locks. */
+ lock_two_nondirectories(s_inode, t_inode);
+ inode1 = s_inode;
+ inode2 = t_inode;
+ if (inode1->i_ino > inode2->i_ino)
+ swap(inode1, inode2);
+
+ status = ocfs2_rw_lock(inode1, 1);
+ if (status) {
+ mlog_errno(status);
+ goto out_i1;
+ }
+ if (!same_inode) {
+ status = ocfs2_rw_lock(inode2, 1);
+ if (status) {
+ mlog_errno(status);
+ goto out_i2;
+ }
+ }
+
+ /* Now go for the cluster locks */
+ oi1 = OCFS2_I(inode1);
+ oi2 = OCFS2_I(inode2);
+
+ trace_ocfs2_double_lock((unsigned long long)oi1->ip_blkno,
+ (unsigned long long)oi2->ip_blkno);
+
+ if (*bh1)
+ *bh1 = NULL;
+ if (*bh2)
+ *bh2 = NULL;
+
+ /* We always want to lock the one with the lower lockid first. */
+ if (oi1->ip_blkno > oi2->ip_blkno)
+ mlog_errno(-ENOLCK);
+
+ /* lock id1 */
+ status = ocfs2_inode_lock_nested(inode1, bh1, 1, OI_LS_REFLINK_TARGET);
+ if (status < 0) {
+ if (status != -ENOENT)
+ mlog_errno(status);
+ goto out_rw2;
+ }
+
+ /* lock id2 */
+ if (!same_inode) {
+ status = ocfs2_inode_lock_nested(inode2, bh2, 1,
+ OI_LS_REFLINK_TARGET);
+ if (status < 0) {
+ if (status != -ENOENT)
+ mlog_errno(status);
+ goto out_cl1;
+ }
+ } else
+ *bh2 = *bh1;
+
+ trace_ocfs2_double_lock_end(
+ (unsigned long long)oi1->ip_blkno,
+ (unsigned long long)oi2->ip_blkno);
+
+ return 0;
+
+out_cl1:
+ ocfs2_inode_unlock(inode1, 1);
+ brelse(*bh1);
+ *bh1 = NULL;
+out_rw2:
+ ocfs2_rw_unlock(inode2, 1);
+out_i2:
+ ocfs2_rw_unlock(inode1, 1);
+out_i1:
+ unlock_two_nondirectories(s_inode, t_inode);
+ return status;
+}
+
+/* Unlock both inodes and release buffers. */
+static void ocfs2_reflink_inodes_unlock(struct inode *s_inode,
+ struct buffer_head *s_bh,
+ struct inode *t_inode,
+ struct buffer_head *t_bh)
+{
+ ocfs2_inode_unlock(s_inode, 1);
+ ocfs2_rw_unlock(s_inode, 1);
+ brelse(s_bh);
+ if (s_inode != t_inode) {
+ ocfs2_inode_unlock(t_inode, 1);
+ ocfs2_rw_unlock(t_inode, 1);
+ brelse(t_bh);
+ }
+ unlock_two_nondirectories(s_inode, t_inode);
+}
+
+/* Link a range of blocks from one file to another. */
+int ocfs2_reflink_remap_range(struct file *file_in,
+ loff_t pos_in,
+ struct file *file_out,
+ loff_t pos_out,
+ u64 len,
+ bool is_dedupe)
+{
+ struct inode *inode_in = file_inode(file_in);
+ struct inode *inode_out = file_inode(file_out);
+ struct ocfs2_super *osb = OCFS2_SB(inode_in->i_sb);
+ struct buffer_head *in_bh = NULL, *out_bh = NULL;
+ bool same_inode = (inode_in == inode_out);
+ ssize_t ret;
+
+ if (!ocfs2_refcount_tree(osb))
+ return -EOPNOTSUPP;
+ if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
+ return -EROFS;
+
+ /* Lock both files against IO */
+ ret = ocfs2_reflink_inodes_lock(inode_in, &in_bh, inode_out, &out_bh);
+ if (ret)
+ return ret;
+
+ /* Check file eligibility and prepare for block sharing. */
+ ret = -EINVAL;
+ if ((OCFS2_I(inode_in)->ip_flags & OCFS2_INODE_SYSTEM_FILE) ||
+ (OCFS2_I(inode_out)->ip_flags & OCFS2_INODE_SYSTEM_FILE))
+ goto out_unlock;
+
+ ret = vfs_clone_file_prep_inodes(inode_in, pos_in, inode_out, pos_out,
+ &len, is_dedupe);
+ if (ret <= 0)
+ goto out_unlock;
+
+ /* Lock out changes to the allocation maps and remap. */
+ down_write(&OCFS2_I(inode_in)->ip_alloc_sem);
+ if (!same_inode)
+ down_write_nested(&OCFS2_I(inode_out)->ip_alloc_sem,
+ SINGLE_DEPTH_NESTING);
+
+ ret = ocfs2_reflink_remap_blocks(inode_in, in_bh, pos_in, inode_out,
+ out_bh, pos_out, len);
+
+ /* Zap any page cache for the destination file's range. */
+ if (!ret)
+ truncate_inode_pages_range(&inode_out->i_data, pos_out,
+ PAGE_ALIGN(pos_out + len) - 1);
+
+ up_write(&OCFS2_I(inode_in)->ip_alloc_sem);
+ if (!same_inode)
+ up_write(&OCFS2_I(inode_out)->ip_alloc_sem);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_unlock;
+ }
+
+ /*
+ * Empty the extent map so that we may get the right extent
+ * record from the disk.
+ */
+ ocfs2_extent_map_trunc(inode_in, 0);
+ ocfs2_extent_map_trunc(inode_out, 0);
+
+ ret = ocfs2_reflink_update_dest(inode_out, out_bh, pos_out + len);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_unlock;
+ }
+
+ ocfs2_reflink_inodes_unlock(inode_in, in_bh, inode_out, out_bh);
+ return 0;
+
+out_unlock:
+ ocfs2_reflink_inodes_unlock(inode_in, in_bh, inode_out, out_bh);
+ return ret;
+}