ocfs2: turn __ocfs2_remove_inode_range() into ocfs2_remove_btree_range()

This patch genericizes the high level handling of extent removal.
ocfs2_remove_btree_range() is nearly identical to
__ocfs2_remove_inode_range(), except that extent tree operations have been
used where necessary. We update ocfs2_remove_inode_range() to use the
generic helper. Now extent tree based structures have an easy way to
truncate ranges.

Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Acked-by: Joel Becker <joel.becker@oracle.com>

3 files changed, 82 insertions, 80 deletions

diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c
index 4614614084dd..5592a2f6335b 100644
--- a/fs/ocfs2/alloc.c
+++ b/fs/ocfs2/alloc.c
@@ -5255,6 +5255,78 @@ out:
         return ret;
 }
 
+int ocfs2_remove_btree_range(struct inode *inode,
+                             struct ocfs2_extent_tree *et,
+                             u32 cpos, u32 phys_cpos, u32 len,
+                             struct ocfs2_cached_dealloc_ctxt *dealloc)
+{
+        int ret;
+        u64 phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
+        struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+        struct inode *tl_inode = osb->osb_tl_inode;
+        handle_t *handle;
+        struct ocfs2_alloc_context *meta_ac = NULL;
+
+        ret = ocfs2_lock_allocators(inode, et, 0, 1, NULL, &meta_ac);
+        if (ret) {
+                mlog_errno(ret);
+                return ret;
+        }
+
+        mutex_lock(&tl_inode->i_mutex);
+
+        if (ocfs2_truncate_log_needs_flush(osb)) {
+                ret = __ocfs2_flush_truncate_log(osb);
+                if (ret < 0) {
+                        mlog_errno(ret);
+                        goto out;
+                }
+        }
+
+        handle = ocfs2_start_trans(osb, OCFS2_REMOVE_EXTENT_CREDITS);
+        if (IS_ERR(handle)) {
+                ret = PTR_ERR(handle);
+                mlog_errno(ret);
+                goto out;
+        }
+
+        ret = ocfs2_journal_access(handle, inode, et->et_root_bh,
+                                   OCFS2_JOURNAL_ACCESS_WRITE);
+        if (ret) {
+                mlog_errno(ret);
+                goto out;
+        }
+
+        ret = ocfs2_remove_extent(inode, et, cpos, len, handle, meta_ac,
+                                  dealloc);
+        if (ret) {
+                mlog_errno(ret);
+                goto out_commit;
+        }
+
+        ocfs2_et_update_clusters(inode, et, -len);
+
+        ret = ocfs2_journal_dirty(handle, et->et_root_bh);
+        if (ret) {
+                mlog_errno(ret);
+                goto out_commit;
+        }
+
+        ret = ocfs2_truncate_log_append(osb, handle, phys_blkno, len);
+        if (ret)
+                mlog_errno(ret);
+
+out_commit:
+        ocfs2_commit_trans(osb, handle);
+out:
+        mutex_unlock(&tl_inode->i_mutex);
+
+        if (meta_ac)
+                ocfs2_free_alloc_context(meta_ac);
+
+        return ret;
+}
+
 int ocfs2_truncate_log_needs_flush(struct ocfs2_super *osb)
 {
         struct buffer_head *tl_bh = osb->osb_tl_bh;
diff --git a/fs/ocfs2/alloc.h b/fs/ocfs2/alloc.h
index 3eb735eedae6..0fbf8fc55a49 100644
--- a/fs/ocfs2/alloc.h
+++ b/fs/ocfs2/alloc.h
@@ -110,6 +110,11 @@ int ocfs2_remove_extent(struct inode *inode,
                         u32 cpos, u32 len, handle_t *handle,
                         struct ocfs2_alloc_context *meta_ac,
                         struct ocfs2_cached_dealloc_ctxt *dealloc);
+int ocfs2_remove_btree_range(struct inode *inode,
+                             struct ocfs2_extent_tree *et,
+                             u32 cpos, u32 phys_cpos, u32 len,
+                             struct ocfs2_cached_dealloc_ctxt *dealloc);
+
 int ocfs2_num_free_extents(struct ocfs2_super *osb,
                            struct inode *inode,
                            struct ocfs2_extent_tree *et);
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index e2570a3bc2b2..360549161e20 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1226,83 +1226,6 @@ out:
         return ret;
 }
 
-static int __ocfs2_remove_inode_range(struct inode *inode,
-                                      struct buffer_head *di_bh,
-                                      u32 cpos, u32 phys_cpos, u32 len,
-                                      struct ocfs2_cached_dealloc_ctxt *dealloc)
-{
-        int ret;
-        u64 phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
-        struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
-        struct inode *tl_inode = osb->osb_tl_inode;
-        handle_t *handle;
-        struct ocfs2_alloc_context *meta_ac = NULL;
-        struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
-        struct ocfs2_extent_tree et;
-
-        ocfs2_init_dinode_extent_tree(&et, inode, di_bh);
-
-        ret = ocfs2_lock_allocators(inode, &et, 0, 1, NULL, &meta_ac);
-        if (ret) {
-                mlog_errno(ret);
-                return ret;
-        }
-
-        mutex_lock(&tl_inode->i_mutex);
-
-        if (ocfs2_truncate_log_needs_flush(osb)) {
-                ret = __ocfs2_flush_truncate_log(osb);
-                if (ret < 0) {
-                        mlog_errno(ret);
-                        goto out;
-                }
-        }
-
-        handle = ocfs2_start_trans(osb, OCFS2_REMOVE_EXTENT_CREDITS);
-        if (IS_ERR(handle)) {
-                ret = PTR_ERR(handle);
-                mlog_errno(ret);
-                goto out;
-        }
-
-        ret = ocfs2_journal_access(handle, inode, di_bh,
-                                   OCFS2_JOURNAL_ACCESS_WRITE);
-        if (ret) {
-                mlog_errno(ret);
-                goto out;
-        }
-
-        ret = ocfs2_remove_extent(inode, &et, cpos, len, handle, meta_ac,
-                                  dealloc);
-        if (ret) {
-                mlog_errno(ret);
-                goto out_commit;
-        }
-
-        OCFS2_I(inode)->ip_clusters -= len;
-        di->i_clusters = cpu_to_le32(OCFS2_I(inode)->ip_clusters);
-
-        ret = ocfs2_journal_dirty(handle, di_bh);
-        if (ret) {
-                mlog_errno(ret);
-                goto out_commit;
-        }
-
-        ret = ocfs2_truncate_log_append(osb, handle, phys_blkno, len);
-        if (ret)
-                mlog_errno(ret);
-
-out_commit:
-        ocfs2_commit_trans(osb, handle);
-out:
-        mutex_unlock(&tl_inode->i_mutex);
-
-        if (meta_ac)
-                ocfs2_free_alloc_context(meta_ac);
-
-        return ret;
-}
-
 /*
  * Truncate a byte range, avoiding pages within partial clusters. This
  * preserves those pages for the zeroing code to write to.
@@ -1402,7 +1325,9 @@ static int ocfs2_remove_inode_range(struct inode *inode,
         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
         struct ocfs2_cached_dealloc_ctxt dealloc;
         struct address_space *mapping = inode->i_mapping;
+        struct ocfs2_extent_tree et;
 
+        ocfs2_init_dinode_extent_tree(&et, inode, di_bh);
         ocfs2_init_dealloc_ctxt(&dealloc);
 
         if (byte_len == 0)
@@ -1458,9 +1383,9 @@ static int ocfs2_remove_inode_range(struct inode *inode,
 
                 /* Only do work for non-holes */
                 if (phys_cpos != 0) {
-                        ret = __ocfs2_remove_inode_range(inode, di_bh, cpos,
-                                                         phys_cpos, alloc_size,
-                                                         &dealloc);
+                        ret = ocfs2_remove_btree_range(inode, &et, cpos,
+                                                       phys_cpos, alloc_size,
+                                                       &dealloc);
                         if (ret) {
                                 mlog_errno(ret);
                                 goto out;