This patch fixes the following hole. dlmlock tries to create a new lock on a lockres that is on purge list. It calls dlm_get_lockresource and later adds a lock to blocked list. But in this window, dlm_thread can purge the lockres and unhash it. This will cause a BUG, as when the AST comes back from the master lockres is not found
This patch marks the lockres with a new state DLM_LOCK_RES_IN_USE which would protect lockres from dlm_thread purging it. Signed-off-by: Srinivas Eeda <[email protected]> Signed-off-by: Sunil Mushran <[email protected]> --- dlmcommon.h | 1 + dlmlock.c | 4 ++++ dlmmaster.c | 5 ++++- dlmthread.c | 1 + 4 files changed, 10 insertions(+), 1 deletion(-) diff -upr ocfs2-1.2.9-8-test/fs/ocfs2/dlm/dlmcommon.h ocfs2-1.2.9-8.2/fs/ocfs2/dlm/dlmcommon.h --- ocfs2-1.2.9-8-test/fs/ocfs2/dlm/dlmcommon.h 2010-06-26 19:04:32.000000000 +0800 +++ ocfs2-1.2.9-8.2/fs/ocfs2/dlm/dlmcommon.h 2010-06-26 19:18:33.000000000 +0800 @@ -218,6 +218,7 @@ static inline void __dlm_set_joining_nod #define DLM_LOCK_RES_IN_PROGRESS 0x00000010 #define DLM_LOCK_RES_MIGRATING 0x00000020 #define DLM_LOCK_RES_DROPPING_REF 0x00000040 +#define DLM_LOCK_RES_IN_USE 0x00000100 #define DLM_LOCK_RES_BLOCK_DIRTY 0x00001000 #define DLM_LOCK_RES_SETREF_INPROG 0x00002000 diff -upr ocfs2-1.2.9-8-test/fs/ocfs2/dlm/dlmlock.c ocfs2-1.2.9-8.2/fs/ocfs2/dlm/dlmlock.c --- ocfs2-1.2.9-8-test/fs/ocfs2/dlm/dlmlock.c 2010-06-26 19:04:22.000000000 +0800 +++ ocfs2-1.2.9-8.2/fs/ocfs2/dlm/dlmlock.c 2010-06-26 19:21:06.000000000 +0800 @@ -116,6 +116,8 @@ static enum dlm_status dlmlock_master(st if (status != DLM_NORMAL && lock->ml.node != dlm->node_num) { /* erf. state changed after lock was dropped. */ + /* DLM_LOCK_RES_IN_USE is set in dlm_get_lock_resource */ + res->state &= ~DLM_LOCK_RES_IN_USE; spin_unlock(&res->spinlock); dlm_error(status); return status; @@ -162,6 +164,7 @@ static enum dlm_status dlmlock_master(st kick_thread = 1; } } + res->state &= ~DLM_LOCK_RES_IN_USE; /* reduce the inflight count, this may result in the lockres * being purged below during calc_usage */ if (lock->ml.node == dlm->node_num) @@ -228,6 +231,7 @@ static enum dlm_status dlmlock_remote(st spin_lock(&res->spinlock); res->state &= ~DLM_LOCK_RES_IN_PROGRESS; + res->state &= ~DLM_LOCK_RES_IN_USE; lock->lock_pending = 0; if (status != DLM_NORMAL) { if (status == DLM_RECOVERING && diff -upr ocfs2-1.2.9-8-test/fs/ocfs2/dlm/dlmmaster.c ocfs2-1.2.9-8.2/fs/ocfs2/dlm/dlmmaster.c --- ocfs2-1.2.9-8-test/fs/ocfs2/dlm/dlmmaster.c 2010-06-26 19:04:22.000000000 +0800 +++ ocfs2-1.2.9-8.2/fs/ocfs2/dlm/dlmmaster.c 2010-06-26 19:23:57.000000000 +0800 @@ -804,12 +804,15 @@ lookup: if (tmpres) { int dropping_ref = 0; + tmpres->state |= DLM_LOCK_RES_IN_USE; spin_lock(&tmpres->spinlock); if (tmpres->owner == dlm->node_num) { BUG_ON(tmpres->state & DLM_LOCK_RES_DROPPING_REF); dlm_lockres_grab_inflight_ref(dlm, tmpres); - } else if (tmpres->state & DLM_LOCK_RES_DROPPING_REF) + } else if (tmpres->state & DLM_LOCK_RES_DROPPING_REF) { + tmpres->state &= ~DLM_LOCK_RES_IN_USE; dropping_ref = 1; + } spin_unlock(&tmpres->spinlock); spin_unlock(&dlm->spinlock); diff -upr ocfs2-1.2.9-8-test/fs/ocfs2/dlm/dlmthread.c ocfs2-1.2.9-8.2/fs/ocfs2/dlm/dlmthread.c --- ocfs2-1.2.9-8-test/fs/ocfs2/dlm/dlmthread.c 2010-06-26 19:04:32.000000000 +0800 +++ ocfs2-1.2.9-8.2/fs/ocfs2/dlm/dlmthread.c 2010-06-26 19:25:06.000000000 +0800 @@ -97,6 +97,7 @@ int __dlm_lockres_has_locks(struct dlm_l int __dlm_lockres_unused(struct dlm_lock_resource *res) { if (!__dlm_lockres_has_locks(res) && + !(res->state & DLM_LOCK_RES_IN_USE) && (list_empty(&res->dirty) && !(res->state & DLM_LOCK_RES_DIRTY))) { /* try not to scan the bitmap unless the first two * conditions are already true */ _______________________________________________ Ocfs2-devel mailing list [email protected] http://oss.oracle.com/mailman/listinfo/ocfs2-devel
