Viewing: ext4-mballoc-pa-free-mismatch.patch
commit 2d3aaef4122c11dcb6d892da89522ffa37036136
Author: Fan Yong <yong.fan@whamcloud.com>
AuthorDate: Thu Feb 25 00:32:12 2010 -0800
Subject: ext4: 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 <yong.fan@whamcloud.com>
Reviewed-by: Alex Zhuravlev <alex.zhuravlev@sun.com>
Reviewed-by: Rahul Deshmukh <rahul.deshmukh@sun.com>
---
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 <linux/seq_file.h>
#include <linux/blkdev.h>
#include <linux/mutex.h>
+#include <linux/genhd.h>
#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 */
};
