[PATCH v5 09/10] ext4: make ext4_insert_delayed_block() insert multi-blocks

From: Zhang Yi
Date: Fri May 17 2024 - 08:53:31 EST


From: Zhang Yi <yi.zhang@xxxxxxxxxx>

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@xxxxxxxxxx>
---
fs/ext4/inode.c | 51 ++++++++++++++++++++++++++++++++++---------------
1 file changed, 36 insertions(+), 15 deletions(-)

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index eefedb7264c7..4febee4c833f 100644
--- 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 @@ static int ext4_da_map_blocks(struct inode *inode, struct ext4_map_blocks *map,
}
}

- 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;
--
2.39.2