[LU-6091] FIEMAP returns empty result until stat(2)

• Type: Bug
• Resolution: Fixed
• Priority: Blocker
• Fix Version/s: Lustre 2.7.0, Lustre 2.5.4
• Affects Version/s: Lustre 2.7.0, Lustre 2.5.4
• Labels: patch
• Severity: 3
• Assignee: Bob Glossman (Inactive)
• Reporter: Li Dongyang (Inactive)

Description

How to reproduce:

With a fresh mounted client or purge the cache by echo 3 > /proc/sys/vm/drop_caches

For any regular file, do a open(2) with O_RDONLY, then FIEMAP ioctl without stat(2). The FIEMAP ioctl will return an empty result.