File 0065-LU-13467-llite-truncate-deadlock-with-DoM-files.patch of Package lustre_2_12

From 8958ecee22010dfa1b99220c2288f7369f490871 Mon Sep 17 00:00:00 2001
From: Andriy Skulysh <c17819@cray.com>
Date: Thu, 27 Feb 2020 23:15:41 +0200
Subject: [PATCH] LU-13467 llite: truncate deadlock with DoM files

All MDT intent RPCs are sent with inode mutex locked
while read/write and setattr unlocks inode mutex on entry,
takes LDLM lock and locks inode mutex again and sends the RPC.
So a deadlock can occur since LDLM lock is the same in case of DoM.

In fact read/write and setattr takes lli_trunc_sem, so
inode mutex can be ommited in truncate case.

Replace inode_lock with new lli_setattr_mutex to keep protection
from concurrent setattr time updates.

HPE-bug-id: LUS-8455
Change-Id: Ie294154306cc3b6cff977a2dff485e8d44145ed9
Reviewed-by: Andrew Perepechko <c17827@cray.com>
Reviewed-by: Vitaly Fertman <c17818@cray.com>
Signed-off-by: Andriy Skulysh <c17819@cray.com>
Reviewed-on: https://review.whamcloud.com/38288
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Mike Pershin <mpershin@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
---
 lustre/llite/llite_internal.h |    1 +
 lustre/llite/llite_lib.c      |    1 +
 lustre/llite/vvp_io.c         |    8 ++++----
 3 files changed, 6 insertions(+), 4 deletions(-)

--- a/lustre/llite/llite_internal.h
+++ b/lustre/llite/llite_internal.h
@@ -190,6 +190,7 @@ struct ll_inode_info {
 			 */
 			struct rw_semaphore	lli_trunc_sem;
 			struct range_lock_tree	lli_write_tree;
+			struct mutex		lli_setattr_mutex;
 
 			struct rw_semaphore	lli_glimpse_sem;
 			ktime_t			lli_glimpse_time;
--- a/lustre/llite/llite_lib.c
+++ b/lustre/llite/llite_lib.c
@@ -984,6 +984,7 @@ void ll_lli_init(struct ll_inode_info *l
 		init_rwsem(&lli->lli_lsm_sem);
 	} else {
 		mutex_init(&lli->lli_size_mutex);
+		mutex_init(&lli->lli_setattr_mutex);
 		lli->lli_symlink_name = NULL;
 		init_rwsem(&lli->lli_trunc_sem);
 		range_lock_tree_init(&lli->lli_write_tree);
--- a/lustre/llite/vvp_io.c
+++ b/lustre/llite/vvp_io.c
@@ -725,10 +725,10 @@ static int vvp_io_setattr_start(const st
 
 	if (cl_io_is_trunc(io)) {
 		down_write(&lli->lli_trunc_sem);
-		inode_lock(inode);
+		mutex_lock(&lli->lli_setattr_mutex);
 		inode_dio_wait(inode);
 	} else {
-		inode_lock(inode);
+		mutex_lock(&lli->lli_setattr_mutex);
 	}
 
 	if (io->u.ci_setattr.sa_avalid & TIMES_SET_FLAGS)
@@ -749,10 +749,10 @@ static void vvp_io_setattr_end(const str
 		 * because osc has already notified to destroy osc_extents. */
 		vvp_do_vmtruncate(inode, io->u.ci_setattr.sa_attr.lvb_size);
 		inode_dio_write_done(inode);
-		inode_unlock(inode);
+		mutex_unlock(&lli->lli_setattr_mutex);
 		up_write(&lli->lli_trunc_sem);
 	} else {
-		inode_unlock(inode);
+		mutex_unlock(&lli->lli_setattr_mutex);
 	}
 }