commit 2d3aaef4122c11dcb6d892da89522ffa37036136 Author: Fan Yong AuthorDate: Thu Feb 25 00:32:12 2010 -0800 Subject: ext4: diagnostic patch to verify lustre read-only device mechanism Diagnostic patch to check whether lustre read-only device mechanism works well or not. Signed-off-by: Fan Yong Reviewed-by: Alex Zhuravlev Reviewed-by: Rahul Deshmukh --- fs/ext4/mballoc.c | 43 +++++++++++++++++++++++++++++++++++++------ fs/ext4/mballoc.h | 2 ++ 2 files changed, 39 insertions(+), 6 deletions(-) --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -3992,6 +3992,7 @@ ext4_mb_new_inode_pa(struct ext4_allocat INIT_LIST_HEAD(&pa->pa_group_list); pa->pa_deleted = 0; pa->pa_type = MB_INODE_PA; + pa->pa_error = 0; mb_debug(sb, "new inode pa %p: %llu/%d for %u\n", pa, pa->pa_pstart, pa->pa_len, pa->pa_lstart); @@ -4046,6 +4047,7 @@ ext4_mb_new_group_pa(struct ext4_allocat INIT_LIST_HEAD(&pa->pa_group_list); pa->pa_deleted = 0; pa->pa_type = MB_GROUP_PA; + pa->pa_error = 0; mb_debug(sb, "new group pa %p: %llu/%d for %u\n", pa, pa->pa_pstart, pa->pa_len, pa->pa_lstart); @@ -4098,7 +4100,9 @@ ext4_mb_release_inode_pa(struct ext4_bud unsigned long long grp_blk_start; int free = 0; + assert_spin_locked(ext4_group_lock_ptr(sb, e4b->bd_group)); BUG_ON(pa->pa_deleted == 0); + BUG_ON(pa->pa_inode == NULL); ext4_get_group_no_and_offset(sb, pa->pa_pstart, &group, &bit); grp_blk_start = pa->pa_pstart - EXT4_C2B(sbi, bit); BUG_ON(group != e4b->bd_group && pa->pa_len != 0); @@ -4121,12 +4125,18 @@ ext4_mb_release_inode_pa(struct ext4_bud mb_free_blocks(pa->pa_inode, e4b, bit, next - bit); bit = next + 1; } - if (free != pa->pa_free) { - ext4_msg(e4b->bd_sb, KERN_CRIT, - "pa %p: logic %lu, phys. %lu, len %d", - pa, (unsigned long) pa->pa_lstart, - (unsigned long) pa->pa_pstart, - pa->pa_len); + + /* "free < pa->pa_free" means we maybe double alloc the same blocks, + * otherwise maybe leave some free blocks unavailable, no need to BUG.*/ + if ((free > pa->pa_free && !pa->pa_error) || (free < pa->pa_free)) { + ext4_error(sb, "pa free mismatch: [pa %p] " + "[phy %lu] [logic %lu] [len %u] [free %u] " + "[error %u] [inode %d] [freed %u]", pa, + (unsigned long)pa->pa_pstart, + (unsigned long)pa->pa_lstart, + pa->pa_len, (unsigned)pa->pa_free, + (unsigned)pa->pa_error, pa->pa_inode->i_ino, + free); ext4_grp_locked_error(sb, group, 0, 0, "free %u, pa_free %u", free, pa->pa_free); /* @@ -4134,6 +4144,8 @@ ext4_mb_release_inode_pa(struct ext4_bud * from the bitmap and continue. */ } + /* do not verify if the file system is being umounted */ + BUG_ON(atomic_read(&sb->s_active) > 0 && pa->pa_free != free); atomic_add(free, &sbi->s_mb_discarded); return 0; @@ -4955,6 +4967,25 @@ errout: ac->ac_b_ex.fe_len = 0; ar->len = 0; ext4_mb_show_ac(ac); + if (ac->ac_pa) { + struct ext4_prealloc_space *pa = ac->ac_pa; + + /* We can not make sure whether the bitmap has + * been updated or not when fail case. So can + * not revert pa_free back, just mark pa_error*/ + pa->pa_error++; + ext4_error(sb, + "Updating bitmap error: [err %d] " + "[pa %p] [phy %lu] [logic %lu] " + "[len %u] [free %u] [error %u] " + "[inode %lu]", *errp, pa, + (unsigned long)pa->pa_pstart, + (unsigned long)pa->pa_lstart, + (unsigned)pa->pa_len, + (unsigned)pa->pa_free, + (unsigned)pa->pa_error, + pa->pa_inode ? pa->pa_inode->i_ino : 0); + } } ext4_mb_release_context(ac); out: --- a/fs/ext4/mballoc.h +++ b/fs/ext4/mballoc.h @@ -20,6 +20,7 @@ #include #include #include +#include #include "ext4_jbd2.h" #include "ext4.h" @@ -107,6 +108,7 @@ struct ext4_prealloc_space { ext4_grpblk_t pa_len; /* len of preallocated chunk */ ext4_grpblk_t pa_free; /* how many blocks are free */ unsigned short pa_type; /* pa type. inode or group */ + unsigned short pa_error; spinlock_t *pa_obj_lock; struct inode *pa_inode; /* hack, for history only */ };