NFS: Implement NFSv4.2's OFFLOAD_STATUS operation

Enable the Linux NFS client to observe the progress of an offloaded
asynchronous COPY operation. This new operation will be put to use
in a subsequent patch.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Link: https://lore.kernel.org/r/20250113153235.48706-14-cel@kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

diff --git a/fs/nfs/nfs42proc.c b/fs/nfs/nfs42proc.c
index 1924c4a2077b12b97343b1c95612c2d691ccd820..3e359e16c324927aefc444b496d2403b7021767c 100644 (file)
--- a/fs/nfs/nfs42proc.c
+++ b/fs/nfs/nfs42proc.c
@@ -21,6 +21,8 @@
 
 #define NFSDBG_FACILITY NFSDBG_PROC
 static int nfs42_do_offload_cancel_async(struct file *dst, nfs4_stateid *std);
+static int nfs42_proc_offload_status(struct file *file, nfs4_stateid *stateid,
+                                    u64 *copied);
 
 static void nfs42_set_netaddr(struct file *filep, struct nfs42_netaddr *naddr)
 {
@@ -582,6 +584,107 @@ static int nfs42_do_offload_cancel_async(struct file *dst,
        return status;
 }
 
+static int
+_nfs42_proc_offload_status(struct nfs_server *server, struct file *file,
+                          struct nfs42_offload_data *data)
+{
+       struct nfs_open_context *ctx = nfs_file_open_context(file);
+       struct rpc_message msg = {
+               .rpc_proc       = &nfs4_procedures[NFSPROC4_CLNT_OFFLOAD_STATUS],
+               .rpc_argp       = &data->args,
+               .rpc_resp       = &data->res,
+               .rpc_cred       = ctx->cred,
+       };
+       int status;
+
+       status = nfs4_call_sync(server->client, server, &msg,
+                               &data->args.osa_seq_args,
+                               &data->res.osr_seq_res, 1);
+       switch (status) {
+       case 0:
+               break;
+
+       case -NFS4ERR_ADMIN_REVOKED:
+       case -NFS4ERR_BAD_STATEID:
+       case -NFS4ERR_OLD_STATEID:
+               /*
+                * Server does not recognize the COPY stateid. CB_OFFLOAD
+                * could have purged it, or server might have rebooted.
+                * Since COPY stateids don't have an associated inode,
+                * avoid triggering state recovery.
+                */
+               status = -EBADF;
+               break;
+       case -NFS4ERR_NOTSUPP:
+       case -ENOTSUPP:
+       case -EOPNOTSUPP:
+               server->caps &= ~NFS_CAP_OFFLOAD_STATUS;
+               status = -EOPNOTSUPP;
+               break;
+       }
+
+       return status;
+}
+
+/**
+ * nfs42_proc_offload_status - Poll completion status of an async copy operation
+ * @dst: handle of file being copied into
+ * @stateid: copy stateid (from async COPY result)
+ * @copied: OUT: number of bytes copied so far
+ *
+ * Return values:
+ *   %0: Server returned an NFS4_OK completion status
+ *   %-EINPROGRESS: Server returned no completion status
+ *   %-EREMOTEIO: Server returned an error completion status
+ *   %-EBADF: Server did not recognize the copy stateid
+ *   %-EOPNOTSUPP: Server does not support OFFLOAD_STATUS
+ *   %-ERESTARTSYS: Wait interrupted by signal
+ *
+ * Other negative errnos indicate the client could not complete the
+ * request.
+ */
+static int __maybe_unused
+nfs42_proc_offload_status(struct file *dst, nfs4_stateid *stateid, u64 *copied)
+{
+       struct inode *inode = file_inode(dst);
+       struct nfs_server *server = NFS_SERVER(inode);
+       struct nfs4_exception exception = {
+               .inode = inode,
+       };
+       struct nfs42_offload_data *data;
+       int status;
+
+       if (!(server->caps & NFS_CAP_OFFLOAD_STATUS))
+               return -EOPNOTSUPP;
+
+       data = kzalloc(sizeof(*data), GFP_KERNEL);
+       if (!data)
+               return -ENOMEM;
+       data->seq_server = server;
+       data->args.osa_src_fh = NFS_FH(inode);
+       memcpy(&data->args.osa_stateid, stateid,
+               sizeof(data->args.osa_stateid));
+       exception.stateid = &data->args.osa_stateid;
+       do {
+               status = _nfs42_proc_offload_status(server, dst, data);
+               if (status == -EOPNOTSUPP)
+                       goto out;
+               status = nfs4_handle_exception(server, status, &exception);
+       } while (exception.retry);
+       if (status)
+               goto out;
+
+       *copied = data->res.osr_count;
+       if (!data->res.complete_count)
+               status = -EINPROGRESS;
+       else if (data->res.osr_complete != NFS_OK)
+               status = -EREMOTEIO;
+
+out:
+       kfree(data);
+       return status;
+}
+
 static int _nfs42_proc_copy_notify(struct file *src, struct file *dst,
                                   struct nfs42_copy_notify_args *args,
                                   struct nfs42_copy_notify_res *res)

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 6e95db6c17e928b70e749a712302f76ebbb412c1..24406fc1352d23fcca69c67ab0483cc8aa3b3386 100644 (file)
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -10781,7 +10781,8 @@ static const struct nfs4_minor_version_ops nfs_v4_2_minor_ops = {
                | NFS_CAP_CLONE
                | NFS_CAP_LAYOUTERROR
                | NFS_CAP_READ_PLUS
-               | NFS_CAP_MOVEABLE,
+               | NFS_CAP_MOVEABLE
+               | NFS_CAP_OFFLOAD_STATUS,
        .init_client = nfs41_init_client,
        .shutdown_client = nfs41_shutdown_client,
        .match_stateid = nfs41_match_stateid,

diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index 108862d81b579830a2c2b78f136928d27ad124f0..1711eefcf24fc60c79d4dcb882f2c20261cf74dd 100644 (file)
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -293,6 +293,7 @@ struct nfs_server {
 #define NFS_CAP_CASE_INSENSITIVE       (1U << 6)
 #define NFS_CAP_CASE_PRESERVING        (1U << 7)
 #define NFS_CAP_REBOOT_LAYOUTRETURN    (1U << 8)
+#define NFS_CAP_OFFLOAD_STATUS (1U << 9)
 #define NFS_CAP_OPEN_XOR       (1U << 12)
 #define NFS_CAP_DELEGTIME      (1U << 13)
 #define NFS_CAP_POSIX_LOCK     (1U << 14)