Commit ff2beee2 authored by Ojaswin Mujoo's avatar Ojaswin Mujoo Committed by Theodore Ts'o
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ext4: convert EXT4_B2C(sbi->s_stripe) users to EXT4_NUM_B2C 



Although we have checks to make sure s_stripe is a multiple of cluster
size, in case we accidentally end up with a scenario where this is not
the case, use EXT4_NUM_B2C() so that we don't end up with unexpected
cases where EXT4_B2C(stripe) becomes 0.

Also make the is_stripe_aligned check in regular_allocator a bit more
robust while we are at it. This should ideally have no functional change
unless we have a bug somewhere causing (stripe % cluster_size != 0)

Reviewed-by: default avatarKemeng Shi <shikemeng@huaweicloud.com>
Signed-off-by: default avatarOjaswin Mujoo <ojaswin@linux.ibm.com>
Reviewed-by: default avatarRitesh Harjani (IBM) <ritesh.list@gmail.com>
Link: https://patch.msgid.link/e0c0a3b58a40935a1361f668851d041575861411.1725002410.git.ojaswin@linux.ibm.com


Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
parent ee85e093

fs/ext4/mballoc.c

+7 −5
Original line number Diff line number Diff line
@@ -2356,7 +2356,7 @@ int ext4_mb_find_by_goal(struct ext4_allocation_context *ac, 
	ex.fe_logical = 0xDEADFA11; /* debug value */



	if (max >= ac->ac_g_ex.fe_len &&

	    ac->ac_g_ex.fe_len == EXT4_B2C(sbi, sbi->s_stripe)) {

	    ac->ac_g_ex.fe_len == EXT4_NUM_B2C(sbi, sbi->s_stripe)) {

		ext4_fsblk_t start;



		start = ext4_grp_offs_to_block(ac->ac_sb, &ex);
@@ -2553,7 +2553,7 @@ void ext4_mb_scan_aligned(struct ext4_allocation_context *ac, 
	do_div(a, sbi->s_stripe);

	i = (a * sbi->s_stripe) - first_group_block;



	stripe = EXT4_B2C(sbi, sbi->s_stripe);

	stripe = EXT4_NUM_B2C(sbi, sbi->s_stripe);

	i = EXT4_B2C(sbi, i);

	while (i < EXT4_CLUSTERS_PER_GROUP(sb)) {

		if (!mb_test_bit(i, bitmap)) {
@@ -2928,9 +2928,11 @@ ext4_mb_regular_allocator(struct ext4_allocation_context *ac) 
			if (cr == CR_POWER2_ALIGNED)

				ext4_mb_simple_scan_group(ac, &e4b);

			else {

				bool is_stripe_aligned = sbi->s_stripe &&

				bool is_stripe_aligned =

					(sbi->s_stripe >=

					 sbi->s_cluster_ratio) &&

					!(ac->ac_g_ex.fe_len %

					  EXT4_B2C(sbi, sbi->s_stripe));

					  EXT4_NUM_B2C(sbi, sbi->s_stripe));



				if ((cr == CR_GOAL_LEN_FAST ||

				     cr == CR_BEST_AVAIL_LEN) &&
@@ -3706,7 +3708,7 @@ int ext4_mb_init(struct super_block *sb) 
	 */

	if (sbi->s_stripe > 1) {

		sbi->s_mb_group_prealloc = roundup(

			sbi->s_mb_group_prealloc, EXT4_B2C(sbi, sbi->s_stripe));

			sbi->s_mb_group_prealloc, EXT4_NUM_B2C(sbi, sbi->s_stripe));

	}



	sbi->s_locality_groups = alloc_percpu(struct ext4_locality_group);