[LU-4209] O_LOV_DELAY_CREATE conflict with __O_TMPFILE

• Type: Bug
• Resolution: Fixed
• Priority: Blocker
• Fix Version/s: Lustre 2.6.0, Lustre 2.5.1
• Labels: MB mn1 mn4
• Environment: On 3.11+ kernels
• Severity: 3

Epic

client

• Assignee: Andreas Dilger
• Reporter: Peng Tao

Description

Since 3.11 kernel release (commit 60545d0d and bb458c64), kernel introduced __O_TMPFILE that unfortunately conflicts with O_LOV_DELAY_CREATE and causes lfs setstripe api to always fail.

#define __O_TMPFILE 020000000

#define O_LOV_DELAY_CREATE 0120000000

Also kernel introduced a safe guard around O_TMPFILE such that whenever __O_TMPFILE bit is set, it has to also have O_DIRECTORY. As a result, it makes Lustre unable to keep backward compatibility. So I am in fact unsure how to solve this. Do we care about O_LOV_DELAY_CREATE compatibility?

Because this is mostly related to user space ABI, I created this ticket so that we can solve it in Lustre tree first, and then I can port the change to kernel client.

Issue Links

• is related to: LU-4416 support for 3.12 linux kernel
• is related to: LU-3373 ldiskfs patches for FC19
• is related to: LU-2182 Add llapi_file_get_layout() function in liblustreapi