2 files changed, 180 insertions, 0 deletions

diff --git a/fs/ocfs2/suballoc.c b/fs/ocfs2/suballoc.c
index e7edda8c6a11..8a286f54dca1 100644
--- a/fs/ocfs2/suballoc.c
+++ b/fs/ocfs2/suballoc.c
@@ -57,6 +57,12 @@ struct ocfs2_suballoc_result {
         u64             sr_bg_blkno;    /* The bg we allocated from.  Set
                                            to 0 when a block group is
                                            contiguous. */
+        u64             sr_bg_stable_blkno; /*
+                                             * Doesn't change, always
+                                             * set to target block
+                                             * group descriptor
+                                             * block.
+                                             */
         u64             sr_blkno;       /* The first allocated block */
         unsigned int    sr_bit_offset;  /* The bit in the bg */
         unsigned int    sr_bits;        /* How many bits we claimed */
@@ -149,6 +155,10 @@ void ocfs2_free_ac_resource(struct ocfs2_alloc_context *ac)
         brelse(ac->ac_bh);
         ac->ac_bh = NULL;
         ac->ac_resv = NULL;
+        if (ac->ac_find_loc_priv) {
+                kfree(ac->ac_find_loc_priv);
+                ac->ac_find_loc_priv = NULL;
+        }
 }
 
 void ocfs2_free_alloc_context(struct ocfs2_alloc_context *ac)
@@ -1689,6 +1699,15 @@ static int ocfs2_search_one_group(struct ocfs2_alloc_context *ac,
         if (!ret)
                 ocfs2_bg_discontig_fix_result(ac, gd, res);
 
+        /*
+         * sr_bg_blkno might have been changed by
+         * ocfs2_bg_discontig_fix_result
+         */
+        res->sr_bg_stable_blkno = group_bh->b_blocknr;
+
+        if (ac->ac_find_loc_only)
+                goto out_loc_only;
+
         ret = ocfs2_alloc_dinode_update_counts(alloc_inode, handle, ac->ac_bh,
                                                res->sr_bits,
                                                le16_to_cpu(gd->bg_chain));
@@ -1702,6 +1721,7 @@ static int ocfs2_search_one_group(struct ocfs2_alloc_context *ac,
         if (ret < 0)
                 mlog_errno(ret);
 
+out_loc_only:
         *bits_left = le16_to_cpu(gd->bg_free_bits_count);
 
 out:
@@ -1780,6 +1800,11 @@ static int ocfs2_search_chain(struct ocfs2_alloc_context *ac,
         if (!status)
                 ocfs2_bg_discontig_fix_result(ac, bg, res);
 
+        /*
+         * sr_bg_blkno might have been changed by
+         * ocfs2_bg_discontig_fix_result
+         */
+        res->sr_bg_stable_blkno = group_bh->b_blocknr;
 
         /*
          * Keep track of previous block descriptor read. When
@@ -1806,6 +1831,9 @@ static int ocfs2_search_chain(struct ocfs2_alloc_context *ac,
                 }
         }
 
+        if (ac->ac_find_loc_only)
+                goto out_loc_only;
+
         status = ocfs2_alloc_dinode_update_counts(alloc_inode, handle,
                                                   ac->ac_bh, res->sr_bits,
                                                   chain);
@@ -1828,6 +1856,7 @@ static int ocfs2_search_chain(struct ocfs2_alloc_context *ac,
         mlog(0, "Allocated %u bits from suballocator %llu\n", res->sr_bits,
              (unsigned long long)le64_to_cpu(fe->i_blkno));
 
+out_loc_only:
         *bits_left = le16_to_cpu(bg->bg_free_bits_count);
 bail:
         brelse(group_bh);
@@ -2023,6 +2052,136 @@ static inline void ocfs2_save_inode_ac_group(struct inode *dir,
         OCFS2_I(dir)->ip_last_used_slot = ac->ac_alloc_slot;
 }
 
+int ocfs2_find_new_inode_loc(struct inode *dir,
+                             struct buffer_head *parent_fe_bh,
+                             struct ocfs2_alloc_context *ac,
+                             u64 *fe_blkno)
+{
+        int ret;
+        handle_t *handle = NULL;
+        struct ocfs2_suballoc_result *res;
+
+        BUG_ON(!ac);
+        BUG_ON(ac->ac_bits_given != 0);
+        BUG_ON(ac->ac_bits_wanted != 1);
+        BUG_ON(ac->ac_which != OCFS2_AC_USE_INODE);
+
+        res = kzalloc(sizeof(*res), GFP_NOFS);
+        if (res == NULL) {
+                ret = -ENOMEM;
+                mlog_errno(ret);
+                goto out;
+        }
+
+        ocfs2_init_inode_ac_group(dir, parent_fe_bh, ac);
+
+        /*
+         * The handle started here is for chain relink. Alternatively,
+         * we could just disable relink for these calls.
+         */
+        handle = ocfs2_start_trans(OCFS2_SB(dir->i_sb), OCFS2_SUBALLOC_ALLOC);
+        if (IS_ERR(handle)) {
+                ret = PTR_ERR(handle);
+                handle = NULL;
+                mlog_errno(ret);
+                goto out;
+        }
+
+        /*
+         * This will instruct ocfs2_claim_suballoc_bits and
+         * ocfs2_search_one_group to search but save actual allocation
+         * for later.
+         */
+        ac->ac_find_loc_only = 1;
+
+        ret = ocfs2_claim_suballoc_bits(ac, handle, 1, 1, res);
+        if (ret < 0) {
+                mlog_errno(ret);
+                goto out;
+        }
+
+        ac->ac_find_loc_priv = res;
+        *fe_blkno = res->sr_blkno;
+
+out:
+        if (handle)
+                ocfs2_commit_trans(OCFS2_SB(dir->i_sb), handle);
+
+        if (ret)
+                kfree(res);
+
+        return ret;
+}
+
+int ocfs2_claim_new_inode_at_loc(handle_t *handle,
+                                 struct inode *dir,
+                                 struct ocfs2_alloc_context *ac,
+                                 u64 *suballoc_loc,
+                                 u16 *suballoc_bit,
+                                 u64 di_blkno)
+{
+        int ret;
+        u16 chain;
+        struct ocfs2_suballoc_result *res = ac->ac_find_loc_priv;
+        struct buffer_head *bg_bh = NULL;
+        struct ocfs2_group_desc *bg;
+        struct ocfs2_dinode *di = (struct ocfs2_dinode *) ac->ac_bh->b_data;
+
+        /*
+         * Since di_blkno is being passed back in, we check for any
+         * inconsistencies which may have happened between
+         * calls. These are code bugs as di_blkno is not expected to
+         * change once returned from ocfs2_find_new_inode_loc()
+         */
+        BUG_ON(res->sr_blkno != di_blkno);
+
+        ret = ocfs2_read_group_descriptor(ac->ac_inode, di,
+                                          res->sr_bg_stable_blkno, &bg_bh);
+        if (ret) {
+                mlog_errno(ret);
+                goto out;
+        }
+
+        bg = (struct ocfs2_group_desc *) bg_bh->b_data;
+        chain = le16_to_cpu(bg->bg_chain);
+
+        ret = ocfs2_alloc_dinode_update_counts(ac->ac_inode, handle,
+                                               ac->ac_bh, res->sr_bits,
+                                               chain);
+        if (ret) {
+                mlog_errno(ret);
+                goto out;
+        }
+
+        ret = ocfs2_block_group_set_bits(handle,
+                                         ac->ac_inode,
+                                         bg,
+                                         bg_bh,
+                                         res->sr_bit_offset,
+                                         res->sr_bits);
+        if (ret < 0) {
+                mlog_errno(ret);
+                goto out;
+        }
+
+        mlog(0, "Allocated %u bits from suballocator %llu\n", res->sr_bits,
+             (unsigned long long)di_blkno);
+
+        atomic_inc(&OCFS2_SB(ac->ac_inode->i_sb)->alloc_stats.bg_allocs);
+
+        BUG_ON(res->sr_bits != 1);
+
+        *suballoc_loc = res->sr_bg_blkno;
+        *suballoc_bit = res->sr_bit_offset;
+        ac->ac_bits_given++;
+        ocfs2_save_inode_ac_group(dir, ac);
+
+out:
+        brelse(bg_bh);
+
+        return ret;
+}
+
 int ocfs2_claim_new_inode(handle_t *handle,
                           struct inode *dir,
                           struct buffer_head *parent_fe_bh,
diff --git a/fs/ocfs2/suballoc.h b/fs/ocfs2/suballoc.h
index a017dd3ee7d9..b8afabfeede4 100644
--- a/fs/ocfs2/suballoc.h
+++ b/fs/ocfs2/suballoc.h
@@ -56,6 +56,9 @@ struct ocfs2_alloc_context {
         u64    ac_max_block;  /* Highest block number to allocate. 0 is
                                  is the same as ~0 - unlimited */
 
+        int    ac_find_loc_only;  /* hack for reflink operation ordering */
+        struct ocfs2_suballoc_result *ac_find_loc_priv; /* */
+
         struct ocfs2_alloc_reservation  *ac_resv;
 };
 
@@ -197,4 +200,22 @@ int ocfs2_lock_allocators(struct inode *inode, struct ocfs2_extent_tree *et,
                           struct ocfs2_alloc_context **meta_ac);
 
 int ocfs2_test_inode_bit(struct ocfs2_super *osb, u64 blkno, int *res);
+
+
+
+/*
+ * The following two interfaces are for ocfs2_create_inode_in_orphan().
+ */
+int ocfs2_find_new_inode_loc(struct inode *dir,
+                             struct buffer_head *parent_fe_bh,
+                             struct ocfs2_alloc_context *ac,
+                             u64 *fe_blkno);
+
+int ocfs2_claim_new_inode_at_loc(handle_t *handle,
+                                 struct inode *dir,
+                                 struct ocfs2_alloc_context *ac,
+                                 u64 *suballoc_loc,
+                                 u16 *suballoc_bit,
+                                 u64 di_blkno);
+
 #endif /* _CHAINALLOC_H_ */