[PATCH RFC 12/24] nfsd: encoders and decoders for GET_DIR_DELEGATION

Jeff Layton
2024-03-15T16:53:45Z

This adds basic infrastructure for handing GET_DIR_DELEGATION calls from
clients, including the decoders and encoders. For now, the server side
always just returns that the delegation is GDDR_UNAVAIL (and that we
won't call back).

Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
fs/nfsd/nfs4proc.c | 30 ++++++++++++++++++++++
fs/nfsd/nfs4xdr.c | 72 ++++++++++++++++++++++++++++++++++++++++++++++++++--
fs/nfsd/xdr4.h | 8 ++++++
include/linux/nfs4.h | 5 ++++
4 files changed, 113 insertions(+), 2 deletions(-)

diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 2927b1263f08..7973fe17bf3c 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -2173,6 +2173,18 @@ nfsd4_layout_verify(struct svc_export *exp, unsigned int layout_type)
return nfsd4_layout_ops[layout_type];
}

+static __be32
+nfsd4_get_dir_delegation(struct svc_rqst *rqstp,
+ struct nfsd4_compound_state *cstate,
+ union nfsd4_op_u *u)
+{
+ struct nfsd4_get_dir_delegation *gdd = &u->get_dir_delegation;
+
+ /* FIXME: actually return a delegation */
+ gdd->nf_status = GDD4_UNAVAIL;
+ return nfs_ok;
+}
+
static __be32
nfsd4_getdeviceinfo(struct svc_rqst *rqstp,
struct nfsd4_compound_state *cstate, union nfsd4_op_u *u)
@@ -3082,6 +3094,18 @@ static u32 nfsd4_copy_notify_rsize(const struct svc_rqst *rqstp,
* sizeof(__be32);
}

+static u32 nfsd4_get_dir_delegation_rsize(const struct svc_rqst *rqstp,
+ const struct nfsd4_op *op)
+{
+ return (op_encode_hdr_size +
+ 1 /* gddr_status */ +
+ op_encode_verifier_maxsz +
+ op_encode_stateid_maxsz +
+ 2 /* gddr_notification */ +
+ 2 /* gddr_child_attributes */ +
+ 2 /* gddr_dir_attributes */);
+}
+
#ifdef CONFIG_NFSD_PNFS
static u32 nfsd4_getdeviceinfo_rsize(const struct svc_rqst *rqstp,
const struct nfsd4_op *op)
@@ -3470,6 +3494,12 @@ static const struct nfsd4_operation nfsd4_ops[] = {
.op_get_currentstateid = nfsd4_get_freestateid,
.op_rsize_bop = nfsd4_only_status_rsize,
},
+ [OP_GET_DIR_DELEGATION] = {
+ .op_func = nfsd4_get_dir_delegation,
+ .op_flags = OP_MODIFIES_SOMETHING,
+ .op_name = "OP_GET_DIR_DELEGATION",
+ .op_rsize_bop = nfsd4_get_dir_delegation_rsize,
+ },
#ifdef CONFIG_NFSD_PNFS
[OP_GETDEVICEINFO] = {
.op_func = nfsd4_getdeviceinfo,
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index fac938f563ad..3718bef74e9f 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -1732,6 +1732,40 @@ nfsd4_decode_free_stateid(struct nfsd4_compoundargs *argp,
return nfsd4_decode_stateid4(argp, &free_stateid->fr_stateid);
}

+static __be32
+nfsd4_decode_get_dir_delegation(struct nfsd4_compoundargs *argp,
+ union nfsd4_op_u *u)
+{
+ struct nfsd4_get_dir_delegation *gdd = &u->get_dir_delegation;
+ struct timespec64 ts;
+ u32 signal_deleg_avail;
+ u32 attrs[1];
+ __be32 status;
+
+ memset(gdd, 0, sizeof(*gdd));
+
+ /* No signal_avail support for now (and maybe never) */
+ if (xdr_stream_decode_bool(argp->xdr, &signal_deleg_avail) < 0)
+ return nfserr_bad_xdr;
+ status = nfsd4_decode_bitmap4(argp, gdd->notification_types,
+ ARRAY_SIZE(gdd->notification_types));
+ if (status)
+ return status;
+
+ /* For now, we don't support child or dir attr change notification */
+ status = nfsd4_decode_nfstime4(argp, &ts);
+ if (status)
+ return status;
+ /* No dir attr notification support yet either */
+ status = nfsd4_decode_nfstime4(argp, &ts);
+ if (status)
+ return status;
+ status = nfsd4_decode_bitmap4(argp, attrs, ARRAY_SIZE(attrs));
+ if (status)
+ return status;
+ return nfsd4_decode_bitmap4(argp, attrs, ARRAY_SIZE(attrs));
+}
+
#ifdef CONFIG_NFSD_PNFS
static __be32
nfsd4_decode_getdeviceinfo(struct nfsd4_compoundargs *argp,
@@ -2370,7 +2404,7 @@ static const nfsd4_dec nfsd4_dec_ops[] = {
[OP_CREATE_SESSION] = nfsd4_decode_create_session,
[OP_DESTROY_SESSION] = nfsd4_decode_destroy_session,
[OP_FREE_STATEID] = nfsd4_decode_free_stateid,
- [OP_GET_DIR_DELEGATION] = nfsd4_decode_notsupp,
+ [OP_GET_DIR_DELEGATION] = nfsd4_decode_get_dir_delegation,
#ifdef CONFIG_NFSD_PNFS
[OP_GETDEVICEINFO] = nfsd4_decode_getdeviceinfo,
[OP_GETDEVICELIST] = nfsd4_decode_notsupp,
@@ -5002,6 +5036,40 @@ nfsd4_encode_device_addr4(struct xdr_stream *xdr,
return nfserr_toosmall;
}

+static __be32
+nfsd4_encode_get_dir_delegation(struct nfsd4_compoundres *resp, __be32 nfserr,
+ union nfsd4_op_u *u)
+{
+ struct xdr_stream *xdr = resp->xdr;
+ struct nfsd4_get_dir_delegation *gdd = &u->get_dir_delegation;
+
+ /* Encode the GDDR_* status code */
+ if (xdr_stream_encode_u32(xdr, gdd->nf_status) != XDR_UNIT)
+ return nfserr_resource;
+
+ /* if it's GDD4_UNAVAIL then we're (almost) done */
+ if (gdd->nf_status == GDD4_UNAVAIL) {
+ /* We never call back */
+ return nfsd4_encode_bool(xdr, false);
+ }
+
+ /* GDD4_OK case */
+ nfserr = nfsd4_encode_verifier4(xdr, &gdd->cookieverf);
+ if (nfserr)
+ return nfserr;
+ nfserr = nfsd4_encode_stateid4(xdr, &gdd->stateid);
+ if (nfserr)
+ return nfserr;
+ /* No notifications (yet) */
+ nfserr = nfsd4_encode_bitmap4(xdr, 0, 0, 0);
+ if (nfserr)
+ return nfserr;
+ nfserr = nfsd4_encode_bitmap4(xdr, 0, 0, 0);
+ if (nfserr)
+ return nfserr;
+ return nfsd4_encode_bitmap4(xdr, 0, 0, 0);
+}
+
static __be32
nfsd4_encode_getdeviceinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
union nfsd4_op_u *u)
@@ -5580,7 +5648,7 @@ static const nfsd4_enc nfsd4_enc_ops[] = {
[OP_CREATE_SESSION] = nfsd4_encode_create_session,
[OP_DESTROY_SESSION] = nfsd4_encode_noop,
[OP_FREE_STATEID] = nfsd4_encode_noop,
- [OP_GET_DIR_DELEGATION] = nfsd4_encode_noop,
+ [OP_GET_DIR_DELEGATION] = nfsd4_encode_get_dir_delegation,
#ifdef CONFIG_NFSD_PNFS
[OP_GETDEVICEINFO] = nfsd4_encode_getdeviceinfo,
[OP_GETDEVICELIST] = nfsd4_encode_noop,
diff --git a/fs/nfsd/xdr4.h b/fs/nfsd/xdr4.h
index 415516c1b27e..27de75f32dea 100644
--- a/fs/nfsd/xdr4.h
+++ b/fs/nfsd/xdr4.h
@@ -518,6 +518,13 @@ struct nfsd4_free_stateid {
stateid_t fr_stateid; /* request */
};

+struct nfsd4_get_dir_delegation {
+ u32 notification_types[1]; /* request */
+ u32 nf_status; /* response */
+ nfs4_verifier cookieverf; /* response */
+ stateid_t stateid; /* response */
+};
+
/* also used for NVERIFY */
struct nfsd4_verify {
u32 ve_bmval[3]; /* request */
@@ -797,6 +804,7 @@ struct nfsd4_op {
struct nfsd4_reclaim_complete reclaim_complete;
struct nfsd4_test_stateid test_stateid;
struct nfsd4_free_stateid free_stateid;
+ struct nfsd4_get_dir_delegation get_dir_delegation;
struct nfsd4_getdeviceinfo getdeviceinfo;
struct nfsd4_layoutget layoutget;
struct nfsd4_layoutcommit layoutcommit;
diff --git a/include/linux/nfs4.h b/include/linux/nfs4.h
index ef8d2d618d5b..11ad088b411d 100644
--- a/include/linux/nfs4.h
+++ b/include/linux/nfs4.h
@@ -701,6 +701,11 @@ enum state_protect_how4 {
SP4_SSV = 2
};

+enum get_dir_delegation_non_fatal_res {
+ GDD4_OK = 0,
+ GDD4_UNAVAIL = 1
+};
+
enum pnfs_layouttype {
LAYOUT_NFSV4_1_FILES = 1,
LAYOUT_OSD2_OBJECTS = 2,

--
2.44.0