ext4: make ext4_insert_delayed_block() insert multi-blocks

Rename ext4_insert_delayed_block() to ext4_insert_delayed_blocks(),
pass length parameter to make it insert multiple delalloc blocks at a
time. For non-bigalloc case, just reserve len blocks and insert delalloc
extent. For bigalloc case, we can ensure that the clusters in the middle
of a extent must be unallocated, we only need to check whether the start
and end clusters are delayed/allocated. We should subtract the space for
the start and/or end block(s) if they are allocated.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20240517124005.347221-10-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 4d8c9ab1ddb1e63792e9dad72133e26626acdf6f..91eb3ba6897003e4ae215e1f7593b8e854abc1e9 100644 (file)
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -1679,24 +1679,29 @@ static int ext4_clu_alloc_state(struct inode *inode, ext4_lblk_t lblk)
 }
 
 /*
- * ext4_insert_delayed_block - adds a delayed block to the extents status
- *                             tree, incrementing the reserved cluster/block
- *                             count or making a pending reservation
- *                             where needed
+ * ext4_insert_delayed_blocks - adds a multiple delayed blocks to the extents
+ *                              status tree, incrementing the reserved
+ *                              cluster/block count or making pending
+ *                              reservations where needed
  *
  * @inode - file containing the newly added block
- * @lblk - logical block to be added
+ * @lblk - start logical block to be added
+ * @len - length of blocks to be added
  *
  * Returns 0 on success, negative error code on failure.
  */
-static int ext4_insert_delayed_block(struct inode *inode, ext4_lblk_t lblk)
+static int ext4_insert_delayed_blocks(struct inode *inode, ext4_lblk_t lblk,
+                                     ext4_lblk_t len)
 {
        struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
        int ret;
-       bool allocated = false;
+       bool lclu_allocated = false;
+       bool end_allocated = false;
+       ext4_lblk_t resv_clu;
+       ext4_lblk_t end = lblk + len - 1;
 
        /*
-        * If the cluster containing lblk is shared with a delayed,
+        * If the cluster containing lblk or end is shared with a delayed,
         * written, or unwritten extent in a bigalloc file system, it's
         * already been accounted for and does not need to be reserved.
         * A pending reservation must be made for the cluster if it's
@@ -1707,23 +1712,39 @@ static int ext4_insert_delayed_block(struct inode *inode, ext4_lblk_t lblk)
         * extents status tree doesn't get a match.
         */
        if (sbi->s_cluster_ratio == 1) {
-               ret = ext4_da_reserve_space(inode, 1);
+               ret = ext4_da_reserve_space(inode, len);
                if (ret != 0)   /* ENOSPC */
                        return ret;
        } else {   /* bigalloc */
+               resv_clu = EXT4_B2C(sbi, end) - EXT4_B2C(sbi, lblk) + 1;
+
                ret = ext4_clu_alloc_state(inode, lblk);
                if (ret < 0)
                        return ret;
-               if (ret == 2)
-                       allocated = true;
-               if (ret == 0) {
-                       ret = ext4_da_reserve_space(inode, 1);
+               if (ret > 0) {
+                       resv_clu--;
+                       lclu_allocated = (ret == 2);
+               }
+
+               if (EXT4_B2C(sbi, lblk) != EXT4_B2C(sbi, end)) {
+                       ret = ext4_clu_alloc_state(inode, end);
+                       if (ret < 0)
+                               return ret;
+                       if (ret > 0) {
+                               resv_clu--;
+                               end_allocated = (ret == 2);
+                       }
+               }
+
+               if (resv_clu) {
+                       ret = ext4_da_reserve_space(inode, resv_clu);
                        if (ret != 0)   /* ENOSPC */
                                return ret;
                }
        }
 
-       ext4_es_insert_delayed_extent(inode, lblk, 1, allocated, false);
+       ext4_es_insert_delayed_extent(inode, lblk, len, lclu_allocated,
+                                     end_allocated);
        return 0;
 }
 
@@ -1828,7 +1849,7 @@ add_delayed:
                }
        }
 
-       retval = ext4_insert_delayed_block(inode, map->m_lblk);
+       retval = ext4_insert_delayed_blocks(inode, map->m_lblk, map->m_len);
        up_write(&EXT4_I(inode)->i_data_sem);
        if (retval)
                return retval;