[PATCH RFC 14/24] nfsd: wire up GET_DIR_DELEGATION handling

Jeff Layton
2024-03-15T16:53:51Z

Add a new routine for acquiring a read delegation on a directory. Since
the same CB_RECALL/DELEGRETURN infrastrure is used for regular and
directory delegations, we can just use a normal nfs4_delegation to
represent it.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
fs/nfsd/nfs4proc.c | 23 ++++++++++++++++--
fs/nfsd/nfs4state.c | 69 ++++++++++++++++++++++++++++++++++++++++++++++++++++-
fs/nfsd/state.h | 5 ++++
3 files changed, 94 insertions(+), 3 deletions(-)

diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 7973fe17bf3c..1a2c90f4ea53 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -2179,9 +2179,28 @@ nfsd4_get_dir_delegation(struct svc_rqst *rqstp,
union nfsd4_op_u *u)
{
struct nfsd4_get_dir_delegation *gdd = &u->get_dir_delegation;
+ struct nfs4_delegation *dd;
+ struct nfsd_file *nf;
+ __be32 status;
+
+ status = nfsd_file_acquire_dir(rqstp, &cstate->current_fh, &nf);
+ if (status != nfs_ok)
+ return status;
+
+ dd = nfsd_get_dir_deleg(cstate, gdd, nf);
+ if (IS_ERR(dd)) {
+ int err = PTR_ERR(dd);
+
+ if (err != -EAGAIN)
+ return nfserrno(err);
+ gdd->nf_status = GDD4_UNAVAIL;
+ return nfs_ok;
+ }

- /* FIXME: actually return a delegation */
- gdd->nf_status = GDD4_UNAVAIL;
+ gdd->nf_status = GDD4_OK;
+ memcpy(&gdd->stateid, &dd->dl_stid.sc_stateid, sizeof(gdd->stateid));
+ memset(&gdd->cookieverf, '\0', sizeof(gdd->cookieverf));
+ nfs4_put_stid(&dd->dl_stid);
return nfs_ok;
}

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 778c1c6e3b54..36574aedc211 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -8874,7 +8874,7 @@ nfsd4_deleg_getattr_conflict(struct svc_rqst *rqstp, struct inode *inode,
}
break_lease:
nfsd_stats_wdeleg_getattr_inc(nn);
- dp = fl->fl_owner;
+ dp = fl->c.flc_owner;
ncf = &dp->dl_cb_fattr;
nfs4_cb_getattr(&dp->dl_cb_fattr);
spin_unlock(&ctx->flc_lock);
@@ -8912,3 +8912,70 @@ nfsd4_deleg_getattr_conflict(struct svc_rqst *rqstp, struct inode *inode,
spin_unlock(&ctx->flc_lock);
return 0;
}
+
+struct nfs4_delegation *
+nfsd_get_dir_deleg(struct nfsd4_compound_state *cstate,
+ struct nfsd4_get_dir_delegation *gdd,
+ struct nfsd_file *nf)
+{
+ struct nfs4_client *clp = cstate->clp;
+ struct nfs4_delegation *dp;
+ struct file_lease *fl;
+ struct nfs4_file *fp;
+ int status = 0;
+
+ fp = nfsd4_alloc_file();
+ if (!fp)
+ return ERR_PTR(-ENOMEM);
+
+ nfsd4_file_init(&cstate->current_fh, fp);
+ fp->fi_deleg_file = nf;
+ fp->fi_delegees = 1;
+
+ spin_lock(&state_lock);
+ spin_lock(&fp->fi_lock);
+ if (nfs4_delegation_exists(clp, fp))
+ status = -EAGAIN;
+ spin_unlock(&fp->fi_lock);
+ spin_unlock(&state_lock);
+
+ if (status)
+ goto out_delegees;
+
+ status = -ENOMEM;
+ dp = alloc_init_deleg(clp, fp, NULL, NFS4_OPEN_DELEGATE_READ);
+ if (!dp)
+ goto out_delegees;
+
+ fl = nfs4_alloc_init_lease(dp, NFS4_OPEN_DELEGATE_READ);
+ if (!fl)
+ goto out_put_stid;
+
+ status = kernel_setlease(nf->nf_file,
+ fl->c.flc_type, &fl, NULL);
+ if (fl)
+ locks_free_lease(fl);
+ if (status)
+ goto out_put_stid;
+
+ spin_lock(&state_lock);
+ spin_lock(&clp->cl_lock);
+ spin_lock(&fp->fi_lock);
+ status = hash_delegation_locked(dp, fp);
+ spin_unlock(&fp->fi_lock);
+ spin_unlock(&clp->cl_lock);
+ spin_unlock(&state_lock);
+
+ if (status)
+ goto out_unlock;
+
+ return dp;
+out_unlock:
+ kernel_setlease(fp->fi_deleg_file->nf_file, F_UNLCK, NULL, (void **)&dp);
+out_put_stid:
+ nfs4_put_stid(&dp->dl_stid);
+out_delegees:
+ put_deleg_file(fp);
+ return ERR_PTR(status);
+}
+
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index 01c6f3445646..20551483cc7b 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -782,4 +782,9 @@ static inline bool try_to_expire_client(struct nfs4_client *clp)

extern __be32 nfsd4_deleg_getattr_conflict(struct svc_rqst *rqstp,
struct inode *inode, bool *file_modified, u64 *size);
+
+struct nfsd4_get_dir_delegation;
+struct nfs4_delegation *nfsd_get_dir_deleg(struct nfsd4_compound_state *cstate,
+ struct nfsd4_get_dir_delegation *gdd,
+ struct nfsd_file *nf);
#endif /* NFSD4_STATE_H */

--
2.44.0