ext4: Move overlap assert logic into a separate function

Abstract out the logic to double check for overlaps in normalize_pa to
a separate function. Since there has been no reports in past where we
have seen any overlaps which hits this bug_on(), in future we can
consider calling this function under "#ifdef AGGRESSIVE_CHECK" only.

There are no functional changes in this patch

Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/35dd5d94fa0b2d1cd2d2947adf8967279c72967d.1679731817.git.ojaswin@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This commit is contained in:
Ojaswin Mujoo 2023-03-25 13:43:37 +05:30 committed by Theodore Ts'o
parent bcf4349921
commit 7692094ac5

View file

@ -3978,6 +3978,29 @@ static void ext4_mb_normalize_group_request(struct ext4_allocation_context *ac)
mb_debug(sb, "goal %u blocks for locality group\n", ac->ac_g_ex.fe_len);
}
static inline void
ext4_mb_pa_assert_overlap(struct ext4_allocation_context *ac,
ext4_lblk_t start, ext4_lblk_t end)
{
struct ext4_sb_info *sbi = EXT4_SB(ac->ac_sb);
struct ext4_inode_info *ei = EXT4_I(ac->ac_inode);
struct ext4_prealloc_space *tmp_pa;
ext4_lblk_t tmp_pa_start, tmp_pa_end;
rcu_read_lock();
list_for_each_entry_rcu(tmp_pa, &ei->i_prealloc_list, pa_inode_list) {
spin_lock(&tmp_pa->pa_lock);
if (tmp_pa->pa_deleted == 0) {
tmp_pa_start = tmp_pa->pa_lstart;
tmp_pa_end = tmp_pa->pa_lstart + EXT4_C2B(sbi, tmp_pa->pa_len);
BUG_ON(!(start >= tmp_pa_end || end <= tmp_pa_start));
}
spin_unlock(&tmp_pa->pa_lock);
}
rcu_read_unlock();
}
/*
* Normalization means making request better in terms of
* size and alignment
@ -4135,17 +4158,7 @@ ext4_mb_normalize_request(struct ext4_allocation_context *ac,
size = end - start;
/* XXX: extra loop to check we really don't overlap preallocations */
rcu_read_lock();
list_for_each_entry_rcu(tmp_pa, &ei->i_prealloc_list, pa_inode_list) {
spin_lock(&tmp_pa->pa_lock);
if (tmp_pa->pa_deleted == 0) {
tmp_pa_start = tmp_pa->pa_lstart;
tmp_pa_end = tmp_pa->pa_lstart + EXT4_C2B(sbi, tmp_pa->pa_len);
BUG_ON(!(start >= tmp_pa_end || end <= tmp_pa_start));
}
spin_unlock(&tmp_pa->pa_lock);
}
rcu_read_unlock();
ext4_mb_pa_assert_overlap(ac, start, end);
/*
* In this function "start" and "size" are normalized for better