[LU-18050] MDT: lease open for remote files (cross open) was broken

• Type: Bug
• Resolution: Unresolved
• Priority: Minor
• Severity: 3
• Assignee: Qian Yingjin
• Reporter: Qian Yingjin

Description

In Lustre, lease open ensure there are only unique opener for a process on a client in the cluster wide. It is used by many places in Lustre such as HSM release, FLR merge/split/resync operations and PCC-RW attach, et, al.

However, the open for remote files via cross open (mdt_cross_open) does not take any DLM ibits lock and check the open lease on the file on the server side. 

This historical legacy issue breaks the open lease semantics.

 

The following test script will fail as the open lease for remote files is broken:

test_853() {
        local dir1=$DIR/$tdir.1
        local dir2=$DIR/$tdir.2
        local file1=$dir1/$tfile
        local file2=$dir2/$tfile


        (( MDSCOUNT > 1 )) || skip "Needs at least 2 MDTs"


        local pid


        # Generate a remote regular file via rename
        $LFS mkdir -i 0 $dir1 || error "failed to mkdir $dir1"
        $LFS mkdir -i 1 $dir2 || error "failed to mkdir $dir2"
        touch $file1 || error "failed to touch $file1"
        mv $file1 $file2 || error "failed to rename $file1 $file2"
        $LFS getstripe -m $file2 $dir1 $dir2


        cancel_lru_locks mdc


        # Test script copied from sanity/test_208.
        echo "==== test 1: verify get lease work"
        $MULTIOP $file2 oO_CREAT:O_RDWR:eRE+eU || error "failed to get lease"


        echo "==== test 2: verify lease can be broken by upcoming open"
        $MULTIOP $file2 oO_RDWR:eR_E-eUc &
        pid=$!
        sleep 2
        $MULTIOP $file2 oO_RDWR:c
        kill -USR1 $pid && wait $pid || error "break lease error"


        echo "==== test 3: verify lease can't be granted if an open already exists"
        $MULTIOP $file2 oO_RDWR:_c &
        pid=$!
        sleep 2
        $MULTIOP $file2 oO_RDWR:eReUc && error "apply lease should fail"
        kill -USR1 $pid && wait $pid || error "failed to open file"
}
run_test 853 "lease for cross-ref open on remote file should not be broken" 

 

Comments

[Gerrit Updater]

"Qian Yingjin <[e-mail]>" uploaded a new patch: https://review.whamcloud.com/c/fs/lustre-release/+/55800
Subject: LU-18050 mdt: fix the broken lease open for remote files
Project: fs/lustre-release
Branch: master
Current Patch Set: 1
Commit: d146c09ef0d70f0a656348de48c06465c22f048f