On 2024/5/12 23:40, Jan Kara wrote:
> On Wed 08-05-24 14:12:18, Zhang Yi wrote:
>> From: Zhang Yi <yi.zhang@xxxxxxxxxx>
>>
>> Factor out a common helper ext4_da_check_clu_allocated(), check whether
>> the cluster containing a delalloc block to be added has been delayed or
>> allocated, no logic changes.
>>
>> Signed-off-by: Zhang Yi <yi.zhang@xxxxxxxxxx>
>
> I have one suggestion for improvement here.
>
>> +/*
>> + * Check whether the cluster containing lblk has been delayed or allocated,
>> + * if not, it means we should reserve a cluster when add delalloc, return 1,
>> + * otherwise return 0 or error code.
>> + */
>> +static int ext4_da_check_clu_allocated(struct inode *inode, ext4_lblk_t lblk,
>> + bool *allocated)
>
> The name of the function does not quite match what it is returning and that
> is confusing. Essentially we have three states here:
>
> a) cluster allocated
> b) cluster has delalloc reservation
> c) cluster doesn't have either
>
> So maybe we could call the function ext4_clu_alloc_state() and return 0 /
> 1 / 2 based on the state?
>
> Honza
Sure, thanks for the suggestion, it looks better.
Thanks,
Yi.
>
>> +{
>> + struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
>> + int ret;
>> +
>> + *allocated = false;
>> + if (ext4_es_scan_clu(inode, &ext4_es_is_delonly, lblk))
>> + return 0;
>> +
>> + if (ext4_es_scan_clu(inode, &ext4_es_is_mapped, lblk))
>> + goto allocated;
>> +
>> + ret = ext4_clu_mapped(inode, EXT4_B2C(sbi, lblk));
>> + if (ret < 0)
>> + return ret;
>> + if (ret == 0)
>> + return 1;
>> +allocated:
>> + *allocated = true;
>> + return 0;
>> +}
>> +
>> /*
>> * ext4_insert_delayed_block - adds a delayed block to the extents status
>> * tree, incrementing the reserved cluster/block
>> @@ -1682,23 +1710,13 @@ static int ext4_insert_delayed_block(struct inode *inode, ext4_lblk_t lblk)
>> if (ret != 0) /* ENOSPC */
>> return ret;
>> } else { /* bigalloc */
>> - if (!ext4_es_scan_clu(inode, &ext4_es_is_delonly, lblk)) {
>> - if (!ext4_es_scan_clu(inode,
>> - &ext4_es_is_mapped, lblk)) {
>> - ret = ext4_clu_mapped(inode,
>> - EXT4_B2C(sbi, lblk));
>> - if (ret < 0)
>> - return ret;
>> - if (ret == 0) {
>> - ret = ext4_da_reserve_space(inode, 1);
>> - if (ret != 0) /* ENOSPC */
>> - return ret;
>> - } else {
>> - allocated = true;
>> - }
>> - } else {
>> - allocated = true;
>> - }
>> + ret = ext4_da_check_clu_allocated(inode, lblk, &allocated);
>> + if (ret < 0)
>> + return ret;
>> + if (ret > 0) {
>> + ret = ext4_da_reserve_space(inode, 1);
>> + if (ret != 0) /* ENOSPC */
>> + return ret;
>> }
>> }
>>
>> --
>> 2.39.2
>>
