ocfs2: Make high level btree extend code generic

Factor out the non-inode specifics of ocfs2_do_extend_allocation() into a more generic
function, ocfs2_do_cluster_allocation(). ocfs2_do_extend_allocation calls
ocfs2_do_cluster_allocation() now, but the latter can be used for other
btree types as well.

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

7 files changed, 176 insertions, 135 deletions

diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c
index 579659bae6c5..cacfc118b71c 100644
--- a/fs/ocfs2/alloc.c
+++ b/fs/ocfs2/alloc.c
@@ -4293,6 +4293,116 @@ bail:
         return status;
 }
 
+/*
+ * Allcate and add clusters into the extent b-tree.
+ * The new clusters(clusters_to_add) will be inserted at logical_offset.
+ * The extent b-tree's root is root_el and it should be in root_bh, and
+ * it is not limited to the file storage. Any extent tree can use this
+ * function if it implements the proper ocfs2_extent_tree.
+ */
+int ocfs2_add_clusters_in_btree(struct ocfs2_super *osb,
+                                struct inode *inode,
+                                u32 *logical_offset,
+                                u32 clusters_to_add,
+                                int mark_unwritten,
+                                struct buffer_head *root_bh,
+                                struct ocfs2_extent_list *root_el,
+                                handle_t *handle,
+                                struct ocfs2_alloc_context *data_ac,
+                                struct ocfs2_alloc_context *meta_ac,
+                                enum ocfs2_alloc_restarted *reason_ret,
+                                enum ocfs2_extent_tree_type type)
+{
+        int status = 0;
+        int free_extents;
+        enum ocfs2_alloc_restarted reason = RESTART_NONE;
+        u32 bit_off, num_bits;
+        u64 block;
+        u8 flags = 0;
+
+        BUG_ON(!clusters_to_add);
+
+        if (mark_unwritten)
+                flags = OCFS2_EXT_UNWRITTEN;
+
+        free_extents = ocfs2_num_free_extents(osb, inode, root_bh, type);
+        if (free_extents < 0) {
+                status = free_extents;
+                mlog_errno(status);
+                goto leave;
+        }
+
+        /* there are two cases which could cause us to EAGAIN in the
+         * we-need-more-metadata case:
+         * 1) we haven't reserved *any*
+         * 2) we are so fragmented, we've needed to add metadata too
+         *    many times. */
+        if (!free_extents && !meta_ac) {
+                mlog(0, "we haven't reserved any metadata!\n");
+                status = -EAGAIN;
+                reason = RESTART_META;
+                goto leave;
+        } else if ((!free_extents)
+                   && (ocfs2_alloc_context_bits_left(meta_ac)
+                       < ocfs2_extend_meta_needed(root_el))) {
+                mlog(0, "filesystem is really fragmented...\n");
+                status = -EAGAIN;
+                reason = RESTART_META;
+                goto leave;
+        }
+
+        status = __ocfs2_claim_clusters(osb, handle, data_ac, 1,
+                                        clusters_to_add, &bit_off, &num_bits);
+        if (status < 0) {
+                if (status != -ENOSPC)
+                        mlog_errno(status);
+                goto leave;
+        }
+
+        BUG_ON(num_bits > clusters_to_add);
+
+        /* reserve our write early -- insert_extent may update the inode */
+        status = ocfs2_journal_access(handle, inode, root_bh,
+                                      OCFS2_JOURNAL_ACCESS_WRITE);
+        if (status < 0) {
+                mlog_errno(status);
+                goto leave;
+        }
+
+        block = ocfs2_clusters_to_blocks(osb->sb, bit_off);
+        mlog(0, "Allocating %u clusters at block %u for inode %llu\n",
+             num_bits, bit_off, (unsigned long long)OCFS2_I(inode)->ip_blkno);
+        status = ocfs2_insert_extent(osb, handle, inode, root_bh,
+                                     *logical_offset, block, num_bits,
+                                     flags, meta_ac, type);
+        if (status < 0) {
+                mlog_errno(status);
+                goto leave;
+        }
+
+        status = ocfs2_journal_dirty(handle, root_bh);
+        if (status < 0) {
+                mlog_errno(status);
+                goto leave;
+        }
+
+        clusters_to_add -= num_bits;
+        *logical_offset += num_bits;
+
+        if (clusters_to_add) {
+                mlog(0, "need to alloc once more, wanted = %u\n",
+                     clusters_to_add);
+                status = -EAGAIN;
+                reason = RESTART_TRANS;
+        }
+
+leave:
+        mlog_exit(status);
+        if (reason_ret)
+                *reason_ret = reason;
+        return status;
+}
+
 static void ocfs2_make_right_split_rec(struct super_block *sb,
                                        struct ocfs2_extent_rec *split_rec,
                                        u32 cpos,
diff --git a/fs/ocfs2/alloc.h b/fs/ocfs2/alloc.h
index 473c8bcc62fb..5e090c5d8498 100644
--- a/fs/ocfs2/alloc.h
+++ b/fs/ocfs2/alloc.h
@@ -41,6 +41,23 @@ int ocfs2_insert_extent(struct ocfs2_super *osb,
                         u8 flags,
                         struct ocfs2_alloc_context *meta_ac,
                         enum ocfs2_extent_tree_type et_type);
+enum ocfs2_alloc_restarted {
+        RESTART_NONE = 0,
+        RESTART_TRANS,
+        RESTART_META
+};
+int ocfs2_add_clusters_in_btree(struct ocfs2_super *osb,
+                                struct inode *inode,
+                                u32 *logical_offset,
+                                u32 clusters_to_add,
+                                int mark_unwritten,
+                                struct buffer_head *root_bh,
+                                struct ocfs2_extent_list *root_el,
+                                handle_t *handle,
+                                struct ocfs2_alloc_context *data_ac,
+                                struct ocfs2_alloc_context *meta_ac,
+                                enum ocfs2_alloc_restarted *reason_ret,
+                                enum ocfs2_extent_tree_type type);
 struct ocfs2_cached_dealloc_ctxt;
 int ocfs2_mark_extent_written(struct inode *inode, struct buffer_head *root_bh,
                               handle_t *handle, u32 cpos, u32 len, u32 phys,
diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index 44ea5eb3fdc4..e7acd2867904 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -1255,10 +1255,10 @@ static int ocfs2_write_cluster(struct address_space *mapping,
                  * any additional semaphores or cluster locks.
                  */
                 tmp_pos = cpos;
-                ret = ocfs2_do_extend_allocation(OCFS2_SB(inode->i_sb), inode,
-                                                 &tmp_pos, 1, 0, wc->w_di_bh,
-                                                 wc->w_handle, data_ac,
-                                                 meta_ac, NULL);
+                ret = ocfs2_add_inode_data(OCFS2_SB(inode->i_sb), inode,
+                                           &tmp_pos, 1, 0, wc->w_di_bh,
+                                           wc->w_handle, data_ac,
+                                           meta_ac, NULL);
                 /*
                  * This shouldn't happen because we must have already
                  * calculated the correct meta data allocation required. The
diff --git a/fs/ocfs2/dir.c b/fs/ocfs2/dir.c
index ba0fb9e16264..d17c34b0ac6b 100644
--- a/fs/ocfs2/dir.c
+++ b/fs/ocfs2/dir.c
@@ -1383,9 +1383,9 @@ static int ocfs2_do_extend_dir(struct super_block *sb,
         if (extend) {
                 u32 offset = OCFS2_I(dir)->ip_clusters;
 
-                status = ocfs2_do_extend_allocation(OCFS2_SB(sb), dir, &offset,
-                                                    1, 0, parent_fe_bh, handle,
-                                                    data_ac, meta_ac, NULL);
+                status = ocfs2_add_inode_data(OCFS2_SB(sb), dir, &offset,
+                                              1, 0, parent_fe_bh, handle,
+                                              data_ac, meta_ac, NULL);
                 BUG_ON(status == -EAGAIN);
                 if (status < 0) {
                         mlog_errno(status);
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index f567cc53d9bc..7bb4fde70054 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -488,7 +488,7 @@ bail:
 }
 
 /*
- * extend allocation only here.
+ * extend file allocation only here.
  * we'll update all the disk stuff, and oip->alloc_size
  *
  * expect stuff to be locked, a transaction started and enough data /
@@ -497,107 +497,25 @@ bail:
  * Will return -EAGAIN, and a reason if a restart is needed.
  * If passed in, *reason will always be set, even in error.
  */
-int ocfs2_do_extend_allocation(struct ocfs2_super *osb,
-                               struct inode *inode,
-                               u32 *logical_offset,
-                               u32 clusters_to_add,
-                               int mark_unwritten,
-                               struct buffer_head *fe_bh,
-                               handle_t *handle,
-                               struct ocfs2_alloc_context *data_ac,
-                               struct ocfs2_alloc_context *meta_ac,
-                               enum ocfs2_alloc_restarted *reason_ret)
+int ocfs2_add_inode_data(struct ocfs2_super *osb,
+                         struct inode *inode,
+                         u32 *logical_offset,
+                         u32 clusters_to_add,
+                         int mark_unwritten,
+                         struct buffer_head *fe_bh,
+                         handle_t *handle,
+                         struct ocfs2_alloc_context *data_ac,
+                         struct ocfs2_alloc_context *meta_ac,
+                         enum ocfs2_alloc_restarted *reason_ret)
 {
-        int status = 0;
-        int free_extents;
         struct ocfs2_dinode *fe = (struct ocfs2_dinode *) fe_bh->b_data;
-        enum ocfs2_alloc_restarted reason = RESTART_NONE;
-        u32 bit_off, num_bits;
-        u64 block;
-        u8 flags = 0;
-
-        BUG_ON(!clusters_to_add);
-
-        if (mark_unwritten)
-                flags = OCFS2_EXT_UNWRITTEN;
-
-        free_extents = ocfs2_num_free_extents(osb, inode, fe_bh,
-                                              OCFS2_DINODE_EXTENT);
-        if (free_extents < 0) {
-                status = free_extents;
-                mlog_errno(status);
-                goto leave;
-        }
-
-        /* there are two cases which could cause us to EAGAIN in the
-         * we-need-more-metadata case:
-         * 1) we haven't reserved *any*
-         * 2) we are so fragmented, we've needed to add metadata too
-         *    many times. */
-        if (!free_extents && !meta_ac) {
-                mlog(0, "we haven't reserved any metadata!\n");
-                status = -EAGAIN;
-                reason = RESTART_META;
-                goto leave;
-        } else if ((!free_extents)
-                   && (ocfs2_alloc_context_bits_left(meta_ac)
-                       < ocfs2_extend_meta_needed(&fe->id2.i_list))) {
-                mlog(0, "filesystem is really fragmented...\n");
-                status = -EAGAIN;
-                reason = RESTART_META;
-                goto leave;
-        }
+        struct ocfs2_extent_list *el = &fe->id2.i_list;
 
-        status = __ocfs2_claim_clusters(osb, handle, data_ac, 1,
-                                        clusters_to_add, &bit_off, &num_bits);
-        if (status < 0) {
-                if (status != -ENOSPC)
-                        mlog_errno(status);
-                goto leave;
-        }
-
-        BUG_ON(num_bits > clusters_to_add);
-
-        /* reserve our write early -- insert_extent may update the inode */
-        status = ocfs2_journal_access(handle, inode, fe_bh,
-                                      OCFS2_JOURNAL_ACCESS_WRITE);
-        if (status < 0) {
-                mlog_errno(status);
-                goto leave;
-        }
-
-        block = ocfs2_clusters_to_blocks(osb->sb, bit_off);
-        mlog(0, "Allocating %u clusters at block %u for inode %llu\n",
-             num_bits, bit_off, (unsigned long long)OCFS2_I(inode)->ip_blkno);
-        status = ocfs2_insert_extent(osb, handle, inode, fe_bh,
-                                     *logical_offset, block, num_bits,
-                                     flags, meta_ac, OCFS2_DINODE_EXTENT);
-        if (status < 0) {
-                mlog_errno(status);
-                goto leave;
-        }
-
-        status = ocfs2_journal_dirty(handle, fe_bh);
-        if (status < 0) {
-                mlog_errno(status);
-                goto leave;
-        }
-
-        clusters_to_add -= num_bits;
-        *logical_offset += num_bits;
-
-        if (clusters_to_add) {
-                mlog(0, "need to alloc once more, clusters = %u, wanted = "
-                     "%u\n", fe->i_clusters, clusters_to_add);
-                status = -EAGAIN;
-                reason = RESTART_TRANS;
-        }
-
-leave:
-        mlog_exit(status);
-        if (reason_ret)
-                *reason_ret = reason;
-        return status;
+        return ocfs2_add_clusters_in_btree(osb, inode, logical_offset,
+                                           clusters_to_add, mark_unwritten,
+                                           fe_bh, el, handle,
+                                           data_ac, meta_ac, reason_ret,
+                                           OCFS2_DINODE_EXTENT);
 }
 
 static int __ocfs2_extend_allocation(struct inode *inode, u32 logical_start,
@@ -676,16 +594,16 @@ restarted_transaction:
 
         prev_clusters = OCFS2_I(inode)->ip_clusters;
 
-        status = ocfs2_do_extend_allocation(osb,
-                                            inode,
-                                            &logical_start,
-                                            clusters_to_add,
-                                            mark_unwritten,
-                                            bh,
-                                            handle,
-                                            data_ac,
-                                            meta_ac,
-                                            &why);
+        status = ocfs2_add_inode_data(osb,
+                                      inode,
+                                      &logical_start,
+                                      clusters_to_add,
+                                      mark_unwritten,
+                                      bh,
+                                      handle,
+                                      data_ac,
+                                      meta_ac,
+                                      &why);
         if ((status < 0) && (status != -EAGAIN)) {
                 if (status != -ENOSPC)
                         mlog_errno(status);
diff --git a/fs/ocfs2/file.h b/fs/ocfs2/file.h
index 18e5c80cc737..e92382cbca5f 100644
--- a/fs/ocfs2/file.h
+++ b/fs/ocfs2/file.h
@@ -33,6 +33,7 @@ extern const struct file_operations ocfs2_dops_no_plocks;
 extern const struct inode_operations ocfs2_file_iops;
 extern const struct inode_operations ocfs2_special_file_iops;
 struct ocfs2_alloc_context;
+enum ocfs2_alloc_restarted;
 
 struct ocfs2_file_private {
         struct file             *fp_file;
@@ -40,21 +41,16 @@ struct ocfs2_file_private {
         struct ocfs2_lock_res   fp_flock;
 };
 
-enum ocfs2_alloc_restarted {
-        RESTART_NONE = 0,
-        RESTART_TRANS,
-        RESTART_META
-};
-int ocfs2_do_extend_allocation(struct ocfs2_super *osb,
-                               struct inode *inode,
-                               u32 *logical_offset,
-                               u32 clusters_to_add,
-                               int mark_unwritten,
-                               struct buffer_head *fe_bh,
-                               handle_t *handle,
-                               struct ocfs2_alloc_context *data_ac,
-                               struct ocfs2_alloc_context *meta_ac,
-                               enum ocfs2_alloc_restarted *reason_ret);
+int ocfs2_add_inode_data(struct ocfs2_super *osb,
+                         struct inode *inode,
+                         u32 *logical_offset,
+                         u32 clusters_to_add,
+                         int mark_unwritten,
+                         struct buffer_head *fe_bh,
+                         handle_t *handle,
+                         struct ocfs2_alloc_context *data_ac,
+                         struct ocfs2_alloc_context *meta_ac,
+                         enum ocfs2_alloc_restarted *reason_ret);
 int ocfs2_extend_no_holes(struct inode *inode, u64 new_i_size,
                           u64 zero_to);
 int ocfs2_setattr(struct dentry *dentry, struct iattr *attr);
diff --git a/fs/ocfs2/namei.c b/fs/ocfs2/namei.c
index d5d808fe0140..2cd6f501755e 100644
--- a/fs/ocfs2/namei.c
+++ b/fs/ocfs2/namei.c
@@ -1598,10 +1598,10 @@ static int ocfs2_symlink(struct inode *dir,
                 u32 offset = 0;
 
                 inode->i_op = &ocfs2_symlink_inode_operations;
-                status = ocfs2_do_extend_allocation(osb, inode, &offset, 1, 0,
-                                                    new_fe_bh,
-                                                    handle, data_ac, NULL,
-                                                    NULL);
+                status = ocfs2_add_inode_data(osb, inode, &offset, 1, 0,
+                                              new_fe_bh,
+                                              handle, data_ac, NULL,
+                                              NULL);
                 if (status < 0) {
                         if (status != -ENOSPC && status != -EINTR) {
                                 mlog(ML_ERROR,