6 files changed, 192 insertions, 3 deletions

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 5c31d6ac9500..329e7fba47d6 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -579,6 +579,8 @@ enum {
 #define EXT4_GET_BLOCKS_KEEP_SIZE               0x0080
         /* Do not take i_data_sem locking in ext4_map_blocks */
 #define EXT4_GET_BLOCKS_NO_LOCK                 0x0100
+        /* Do not put hole in extent cache */
+#define EXT4_GET_BLOCKS_NO_PUT_HOLE             0x0200
 
 /*
  * Flags used by ext4_free_blocks
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index be0b1b3eed97..b9d7a2363736 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -2167,6 +2167,9 @@ ext4_ext_put_gap_in_cache(struct inode *inode, struct ext4_ext_path *path,
                                 block,
                                 le32_to_cpu(ex->ee_block),
                                  ext4_ext_get_actual_len(ex));
+                if (!ext4_find_delalloc_range(inode, lblock, lblock + len - 1))
+                        ext4_es_insert_extent(inode, lblock, len, ~0,
+                                              EXTENT_STATUS_HOLE);
         } else if (block >= le32_to_cpu(ex->ee_block)
                         + ext4_ext_get_actual_len(ex)) {
                 ext4_lblk_t next;
@@ -2180,6 +2183,9 @@ ext4_ext_put_gap_in_cache(struct inode *inode, struct ext4_ext_path *path,
                                 block);
                 BUG_ON(next == lblock);
                 len = next - lblock;
+                if (!ext4_find_delalloc_range(inode, lblock, lblock + len - 1))
+                        ext4_es_insert_extent(inode, lblock, len, ~0,
+                                              EXTENT_STATUS_HOLE);
         } else {
                 lblock = len = 0;
                 BUG();
@@ -4018,7 +4024,8 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
                  * put just found gap into cache to speed up
                  * subsequent requests
                  */
-                ext4_ext_put_gap_in_cache(inode, path, map->m_lblk);
+                if ((flags & EXT4_GET_BLOCKS_NO_PUT_HOLE) == 0)
+                        ext4_ext_put_gap_in_cache(inode, path, map->m_lblk);
                 goto out2;
         }
 
diff --git a/fs/ext4/extents_status.c b/fs/ext4/extents_status.c
index 76f4351ea821..eeb893122d8d 100644
--- a/fs/ext4/extents_status.c
+++ b/fs/ext4/extents_status.c
@@ -461,6 +461,66 @@ error:
         return err;
 }
 
+/*
+ * ext4_es_lookup_extent() looks up an extent in extent status tree.
+ *
+ * ext4_es_lookup_extent is called by ext4_map_blocks/ext4_da_map_blocks.
+ *
+ * Return: 1 on found, 0 on not
+ */
+int ext4_es_lookup_extent(struct inode *inode, ext4_lblk_t lblk,
+                          struct extent_status *es)
+{
+        struct ext4_es_tree *tree;
+        struct extent_status *es1 = NULL;
+        struct rb_node *node;
+        int found = 0;
+
+        trace_ext4_es_lookup_extent_enter(inode, lblk);
+        es_debug("lookup extent in block %u\n", lblk);
+
+        tree = &EXT4_I(inode)->i_es_tree;
+        read_lock(&EXT4_I(inode)->i_es_lock);
+
+        /* find extent in cache firstly */
+        es->es_lblk = es->es_len = es->es_pblk = 0;
+        if (tree->cache_es) {
+                es1 = tree->cache_es;
+                if (in_range(lblk, es1->es_lblk, es1->es_len)) {
+                        es_debug("%u cached by [%u/%u)\n",
+                                 lblk, es1->es_lblk, es1->es_len);
+                        found = 1;
+                        goto out;
+                }
+        }
+
+        node = tree->root.rb_node;
+        while (node) {
+                es1 = rb_entry(node, struct extent_status, rb_node);
+                if (lblk < es1->es_lblk)
+                        node = node->rb_left;
+                else if (lblk > ext4_es_end(es1))
+                        node = node->rb_right;
+                else {
+                        found = 1;
+                        break;
+                }
+        }
+
+out:
+        if (found) {
+                BUG_ON(!es1);
+                es->es_lblk = es1->es_lblk;
+                es->es_len = es1->es_len;
+                es->es_pblk = es1->es_pblk;
+        }
+
+        read_unlock(&EXT4_I(inode)->i_es_lock);
+
+        trace_ext4_es_lookup_extent_exit(inode, es, found);
+        return found;
+}
+
 static int __es_remove_extent(struct ext4_es_tree *tree, ext4_lblk_t lblk,
                                  ext4_lblk_t end)
 {
diff --git a/fs/ext4/extents_status.h b/fs/ext4/extents_status.h
index 3f69d097c6e7..8ffc90c784fa 100644
--- a/fs/ext4/extents_status.h
+++ b/fs/ext4/extents_status.h
@@ -53,6 +53,8 @@ extern int ext4_es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
                                  ext4_lblk_t len);
 extern void ext4_es_find_delayed_extent(struct inode *inode, ext4_lblk_t lblk,
                                         struct extent_status *es);
+extern int ext4_es_lookup_extent(struct inode *inode, ext4_lblk_t lblk,
+                                 struct extent_status *es);
 
 static inline int ext4_es_is_written(struct extent_status *es)
 {
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 576b586b61aa..95a0c62c5683 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -507,12 +507,33 @@ static pgoff_t ext4_num_dirty_pages(struct inode *inode, pgoff_t idx,
 int ext4_map_blocks(handle_t *handle, struct inode *inode,
                     struct ext4_map_blocks *map, int flags)
 {
+        struct extent_status es;
         int retval;
 
         map->m_flags = 0;
         ext_debug("ext4_map_blocks(): inode %lu, flag %d, max_blocks %u,"
                   "logical block %lu\n", inode->i_ino, flags, map->m_len,
                   (unsigned long) map->m_lblk);
+
+        /* Lookup extent status tree firstly */
+        if (ext4_es_lookup_extent(inode, map->m_lblk, &es)) {
+                if (ext4_es_is_written(&es) || ext4_es_is_unwritten(&es)) {
+                        map->m_pblk = ext4_es_pblock(&es) +
+                                        map->m_lblk - es.es_lblk;
+                        map->m_flags |= ext4_es_is_written(&es) ?
+                                        EXT4_MAP_MAPPED : EXT4_MAP_UNWRITTEN;
+                        retval = es.es_len - (map->m_lblk - es.es_lblk);
+                        if (retval > map->m_len)
+                                retval = map->m_len;
+                        map->m_len = retval;
+                } else if (ext4_es_is_delayed(&es) || ext4_es_is_hole(&es)) {
+                        retval = 0;
+                } else {
+                        BUG_ON(1);
+                }
+                goto found;
+        }
+
         /*
          * Try to see if we can get the block without requesting a new
          * file system block.
@@ -544,6 +565,7 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode,
         if (!(flags & EXT4_GET_BLOCKS_NO_LOCK))
                 up_read((&EXT4_I(inode)->i_data_sem));
 
+found:
         if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED) {
                 int ret = check_block_validity(inode, map);
                 if (ret != 0)
@@ -1743,6 +1765,7 @@ static int ext4_da_map_blocks(struct inode *inode, sector_t iblock,
                               struct ext4_map_blocks *map,
                               struct buffer_head *bh)
 {
+        struct extent_status es;
         int retval;
         sector_t invalid_block = ~((sector_t) 0xffff);
 
@@ -1753,6 +1776,42 @@ static int ext4_da_map_blocks(struct inode *inode, sector_t iblock,
         ext_debug("ext4_da_map_blocks(): inode %lu, max_blocks %u,"
                   "logical block %lu\n", inode->i_ino, map->m_len,
                   (unsigned long) map->m_lblk);
+
+        /* Lookup extent status tree firstly */
+        if (ext4_es_lookup_extent(inode, iblock, &es)) {
+
+                if (ext4_es_is_hole(&es)) {
+                        retval = 0;
+                        down_read((&EXT4_I(inode)->i_data_sem));
+                        goto add_delayed;
+                }
+
+                /*
+                 * Delayed extent could be allocated by fallocate.
+                 * So we need to check it.
+                 */
+                if (ext4_es_is_delayed(&es) && !ext4_es_is_unwritten(&es)) {
+                        map_bh(bh, inode->i_sb, invalid_block);
+                        set_buffer_new(bh);
+                        set_buffer_delay(bh);
+                        return 0;
+                }
+
+                map->m_pblk = ext4_es_pblock(&es) + iblock - es.es_lblk;
+                retval = es.es_len - (iblock - es.es_lblk);
+                if (retval > map->m_len)
+                        retval = map->m_len;
+                map->m_len = retval;
+                if (ext4_es_is_written(&es))
+                        map->m_flags |= EXT4_MAP_MAPPED;
+                else if (ext4_es_is_unwritten(&es))
+                        map->m_flags |= EXT4_MAP_UNWRITTEN;
+                else
+                        BUG_ON(1);
+
+                return retval;
+        }
+
         /*
          * Try to see if we can get the block without requesting a new
          * file system block.
@@ -1771,10 +1830,13 @@ static int ext4_da_map_blocks(struct inode *inode, sector_t iblock,
                         map->m_flags |= EXT4_MAP_FROM_CLUSTER;
                 retval = 0;
         } else if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
-                retval = ext4_ext_map_blocks(NULL, inode, map, 0);
+                retval = ext4_ext_map_blocks(NULL, inode, map,
+                                             EXT4_GET_BLOCKS_NO_PUT_HOLE);
         else
-                retval = ext4_ind_map_blocks(NULL, inode, map, 0);
+                retval = ext4_ind_map_blocks(NULL, inode, map,
+                                             EXT4_GET_BLOCKS_NO_PUT_HOLE);
 
+add_delayed:
         if (retval == 0) {
                 int ret;
                 /*
diff --git a/include/trace/events/ext4.h b/include/trace/events/ext4.h
index c121cdf55ab3..1e590b68cec4 100644
--- a/include/trace/events/ext4.h
+++ b/include/trace/events/ext4.h
@@ -2199,6 +2199,62 @@ TRACE_EVENT(ext4_es_find_delayed_extent_exit,
                   __entry->pblk, __entry->status)
 );
 
+TRACE_EVENT(ext4_es_lookup_extent_enter,
+        TP_PROTO(struct inode *inode, ext4_lblk_t lblk),
+
+        TP_ARGS(inode, lblk),
+
+        TP_STRUCT__entry(
+                __field(        dev_t,          dev             )
+                __field(        ino_t,          ino             )
+                __field(        ext4_lblk_t,    lblk            )
+        ),
+
+        TP_fast_assign(
+                __entry->dev    = inode->i_sb->s_dev;
+                __entry->ino    = inode->i_ino;
+                __entry->lblk   = lblk;
+        ),
+
+        TP_printk("dev %d,%d ino %lu lblk %u",
+                  MAJOR(__entry->dev), MINOR(__entry->dev),
+                  (unsigned long) __entry->ino, __entry->lblk)
+);
+
+TRACE_EVENT(ext4_es_lookup_extent_exit,
+        TP_PROTO(struct inode *inode, struct extent_status *es,
+                 int found),
+
+        TP_ARGS(inode, es, found),
+
+        TP_STRUCT__entry(
+                __field(        dev_t,          dev             )
+                __field(        ino_t,          ino             )
+                __field(        ext4_lblk_t,    lblk            )
+                __field(        ext4_lblk_t,    len             )
+                __field(        ext4_fsblk_t,   pblk            )
+                __field(        unsigned long long,     status  )
+                __field(        int,            found           )
+        ),
+
+        TP_fast_assign(
+                __entry->dev    = inode->i_sb->s_dev;
+                __entry->ino    = inode->i_ino;
+                __entry->lblk   = es->es_lblk;
+                __entry->len    = es->es_len;
+                __entry->pblk   = ext4_es_pblock(es);
+                __entry->status = ext4_es_status(es);
+                __entry->found  = found;
+        ),
+
+        TP_printk("dev %d,%d ino %lu found %d [%u/%u) %llu %llx",
+                  MAJOR(__entry->dev), MINOR(__entry->dev),
+                  (unsigned long) __entry->ino, __entry->found,
+                  __entry->lblk, __entry->len,
+                  __entry->found ? __entry->pblk : 0,
+                  __entry->found ? __entry->status : 0)
+);
+
 #endif /* _TRACE_EXT4_H */
 
 /* This part must be outside protection */