[PATCH v3 0/7] Client-side OFFLOAD_STATUS implementation

cel
2025-01-13T15:32:46Z

SCSI implementation experience has shown that an interrupt-only
COPY offload implementation is not reliable. There are too many
common scenarios where the client can miss the completion interrupt
(in our case, this is an NFSv4.2 CB_OFFLOAD callback).

Therefore, a polling mechanism is needed. The NFSv4.2 protocol
provides one in the form of the its OFFLOAD_STATUS operation. Linux
NFSD implements OFFLOAD_STATUS already. This series adds a Linux NFS
client implementation of the OFFLOAD_STATUS operation that can query
the state of a background COPY on the server.

These patches are also available here:

https://git.kernel.org/pub/scm/linux/kernel/git/cel/linux.git/log/?h=fix-async-copy

Reposting to restart the review process.

Changes since v2:
- Use an exponential backoff before posting OFFLOAD_STATUS

Chuck Lever (7):
NFS: CB_OFFLOAD can return NFS4ERR_DELAY
NFS: Fix typo in OFFLOAD_CANCEL comment
NFS: Rename struct nfs4_offloadcancel_data
NFS: Implement NFSv4.2's OFFLOAD_STATUS XDR
NFS: Implement NFSv4.2's OFFLOAD_STATUS operation
NFS: Use NFSv4.2's OFFLOAD_STATUS operation
NFS: Refactor trace_nfs4_offload_cancel

fs/nfs/callback_proc.c | 2 +-
fs/nfs/nfs42proc.c | 190 ++++++++++++++++++++++++++++++++++----
fs/nfs/nfs42xdr.c | 88 +++++++++++++++++-
fs/nfs/nfs4proc.c | 3 +-
fs/nfs/nfs4trace.h | 11 ++-
fs/nfs/nfs4xdr.c | 1 +
include/linux/nfs4.h | 1 +
include/linux/nfs_fs_sb.h | 1 +
include/linux/nfs_xdr.h | 5 +-
9 files changed, 277 insertions(+), 25 deletions(-)

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2.47.0