1 files changed, 162 insertions, 10 deletions

diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 9f7fc51ca334..e7d7a837512a 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -3194,7 +3194,7 @@ static int log_inode_item(struct btrfs_trans_handle *trans,
 static noinline int copy_items(struct btrfs_trans_handle *trans,
                                struct inode *inode,
                                struct btrfs_path *dst_path,
-                               struct extent_buffer *src,
+                               struct btrfs_path *src_path, u64 *last_extent,
                                int start_slot, int nr, int inode_only)
 {
         unsigned long src_offset;
@@ -3202,6 +3202,8 @@ static noinline int copy_items(struct btrfs_trans_handle *trans,
         struct btrfs_root *log = BTRFS_I(inode)->root->log_root;
         struct btrfs_file_extent_item *extent;
         struct btrfs_inode_item *inode_item;
+        struct extent_buffer *src = src_path->nodes[0];
+        struct btrfs_key first_key, last_key, key;
         int ret;
         struct btrfs_key *ins_keys;
         u32 *ins_sizes;
@@ -3209,6 +3211,9 @@ static noinline int copy_items(struct btrfs_trans_handle *trans,
         int i;
         struct list_head ordered_sums;
         int skip_csum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
+        bool has_extents = false;
+        bool need_find_last_extent = (*last_extent == 0);
+        bool done = false;
 
         INIT_LIST_HEAD(&ordered_sums);
 
@@ -3217,6 +3222,8 @@ static noinline int copy_items(struct btrfs_trans_handle *trans,
         if (!ins_data)
                 return -ENOMEM;
 
+        first_key.objectid = (u64)-1;
+
         ins_sizes = (u32 *)ins_data;
         ins_keys = (struct btrfs_key *)(ins_data + nr * sizeof(u32));
 
@@ -3237,6 +3244,9 @@ static noinline int copy_items(struct btrfs_trans_handle *trans,
 
                 src_offset = btrfs_item_ptr_offset(src, start_slot + i);
 
+                if ((i == (nr - 1)))
+                        last_key = ins_keys[i];
+
                 if (ins_keys[i].type == BTRFS_INODE_ITEM_KEY) {
                         inode_item = btrfs_item_ptr(dst_path->nodes[0],
                                                     dst_path->slots[0],
@@ -3248,6 +3258,21 @@ static noinline int copy_items(struct btrfs_trans_handle *trans,
                                            src_offset, ins_sizes[i]);
                 }
 
+                /*
+                 * We set need_find_last_extent here in case we know we were
+                 * processing other items and then walk into the first extent in
+                 * the inode.  If we don't hit an extent then nothing changes,
+                 * we'll do the last search the next time around.
+                 */
+                if (ins_keys[i].type == BTRFS_EXTENT_DATA_KEY) {
+                        has_extents = true;
+                        if (need_find_last_extent &&
+                            first_key.objectid == (u64)-1)
+                                first_key = ins_keys[i];
+                } else {
+                        need_find_last_extent = false;
+                }
+
                 /* take a reference on file data extents so that truncates
                  * or deletes of this inode don't have to relog the inode
                  * again
@@ -3312,6 +3337,126 @@ static noinline int copy_items(struct btrfs_trans_handle *trans,
                 list_del(&sums->list);
                 kfree(sums);
         }
+
+        if (!has_extents)
+                return ret;
+
+        /*
+         * Because we use btrfs_search_forward we could skip leaves that were
+         * not modified and then assume *last_extent is valid when it really
+         * isn't.  So back up to the previous leaf and read the end of the last
+         * extent before we go and fill in holes.
+         */
+        if (need_find_last_extent) {
+                u64 len;
+
+                ret = btrfs_prev_leaf(BTRFS_I(inode)->root, src_path);
+                if (ret < 0)
+                        return ret;
+                if (ret)
+                        goto fill_holes;
+                if (src_path->slots[0])
+                        src_path->slots[0]--;
+                src = src_path->nodes[0];
+                btrfs_item_key_to_cpu(src, &key, src_path->slots[0]);
+                if (key.objectid != btrfs_ino(inode) ||
+                    key.type != BTRFS_EXTENT_DATA_KEY)
+                        goto fill_holes;
+                extent = btrfs_item_ptr(src, src_path->slots[0],
+                                        struct btrfs_file_extent_item);
+                if (btrfs_file_extent_type(src, extent) ==
+                    BTRFS_FILE_EXTENT_INLINE) {
+                        len = btrfs_file_extent_inline_len(src, extent);
+                        *last_extent = ALIGN(key.offset + len,
+                                             log->sectorsize);
+                } else {
+                        len = btrfs_file_extent_num_bytes(src, extent);
+                        *last_extent = key.offset + len;
+                }
+        }
+fill_holes:
+        /* So we did prev_leaf, now we need to move to the next leaf, but a few
+         * things could have happened
+         *
+         * 1) A merge could have happened, so we could currently be on a leaf
+         * that holds what we were copying in the first place.
+         * 2) A split could have happened, and now not all of the items we want
+         * are on the same leaf.
+         *
+         * So we need to adjust how we search for holes, we need to drop the
+         * path and re-search for the first extent key we found, and then walk
+         * forward until we hit the last one we copied.
+         */
+        if (need_find_last_extent) {
+                /* btrfs_prev_leaf could return 1 without releasing the path */
+                btrfs_release_path(src_path);
+                ret = btrfs_search_slot(NULL, BTRFS_I(inode)->root, &first_key,
+                                        src_path, 0, 0);
+                if (ret < 0)
+                        return ret;
+                ASSERT(ret == 0);
+                src = src_path->nodes[0];
+                i = src_path->slots[0];
+        } else {
+                i = start_slot;
+        }
+
+        /*
+         * Ok so here we need to go through and fill in any holes we may have
+         * to make sure that holes are punched for those areas in case they had
+         * extents previously.
+         */
+        while (!done) {
+                u64 offset, len;
+                u64 extent_end;
+
+                if (i >= btrfs_header_nritems(src_path->nodes[0])) {
+                        ret = btrfs_next_leaf(BTRFS_I(inode)->root, src_path);
+                        if (ret < 0)
+                                return ret;
+                        ASSERT(ret == 0);
+                        src = src_path->nodes[0];
+                        i = 0;
+                }
+
+                btrfs_item_key_to_cpu(src, &key, i);
+                if (!btrfs_comp_cpu_keys(&key, &last_key))
+                        done = true;
+                if (key.objectid != btrfs_ino(inode) ||
+                    key.type != BTRFS_EXTENT_DATA_KEY) {
+                        i++;
+                        continue;
+                }
+                extent = btrfs_item_ptr(src, i, struct btrfs_file_extent_item);
+                if (btrfs_file_extent_type(src, extent) ==
+                    BTRFS_FILE_EXTENT_INLINE) {
+                        len = btrfs_file_extent_inline_len(src, extent);
+                        extent_end = ALIGN(key.offset + len, log->sectorsize);
+                } else {
+                        len = btrfs_file_extent_num_bytes(src, extent);
+                        extent_end = key.offset + len;
+                }
+                i++;
+
+                if (*last_extent == key.offset) {
+                        *last_extent = extent_end;
+                        continue;
+                }
+                offset = *last_extent;
+                len = key.offset - *last_extent;
+                ret = btrfs_insert_file_extent(trans, log, btrfs_ino(inode),
+                                               offset, 0, 0, len, 0, len, 0,
+                                               0, 0);
+                if (ret)
+                        break;
+                *last_extent = offset + len;
+        }
+        /*
+         * Need to let the callers know we dropped the path so they should
+         * re-search.
+         */
+        if (!ret && need_find_last_extent)
+                ret = 1;
         return ret;
 }
 
@@ -3630,6 +3775,7 @@ static int btrfs_log_inode(struct btrfs_trans_handle *trans,
         struct btrfs_key max_key;
         struct btrfs_root *log = root->log_root;
         struct extent_buffer *src = NULL;
+        u64 last_extent = 0;
         int err = 0;
         int ret;
         int nritems;
@@ -3745,11 +3891,15 @@ again:
                         goto next_slot;
                 }
 
-                ret = copy_items(trans, inode, dst_path, src, ins_start_slot,
-                                 ins_nr, inode_only);
-                if (ret) {
+                ret = copy_items(trans, inode, dst_path, path, &last_extent,
+                                 ins_start_slot, ins_nr, inode_only);
+                if (ret < 0) {
                         err = ret;
                         goto out_unlock;
+                } if (ret) {
+                        ins_nr = 0;
+                        btrfs_release_path(path);
+                        continue;
                 }
                 ins_nr = 1;
                 ins_start_slot = path->slots[0];
@@ -3763,13 +3913,14 @@ next_slot:
                         goto again;
                 }
                 if (ins_nr) {
-                        ret = copy_items(trans, inode, dst_path, src,
-                                         ins_start_slot,
+                        ret = copy_items(trans, inode, dst_path, path,
+                                         &last_extent, ins_start_slot,
                                          ins_nr, inode_only);
-                        if (ret) {
+                        if (ret < 0) {
                                 err = ret;
                                 goto out_unlock;
                         }
+                        ret = 0;
                         ins_nr = 0;
                 }
                 btrfs_release_path(path);
@@ -3784,12 +3935,13 @@ next_slot:
                 }
         }
         if (ins_nr) {
-                ret = copy_items(trans, inode, dst_path, src, ins_start_slot,
-                                 ins_nr, inode_only);
-                if (ret) {
+                ret = copy_items(trans, inode, dst_path, path, &last_extent,
+                                 ins_start_slot, ins_nr, inode_only);
+                if (ret < 0) {
                         err = ret;
                         goto out_unlock;
                 }
+                ret = 0;
                 ins_nr = 0;
         }