On Tue, 15 Oct 2024, Jeff Layton wrote:
> Add support for the delegated timestamps on write delegations. This
> allows the server to proxy timestamps from the delegation holder to
> other clients that are doing GETATTRs vs. the same inode.
>
> When OPEN4_SHARE_ACCESS_WANT_DELEG_TIMESTAMPS bit is set in the OPEN
> call, set the dl_type to the *_ATTRS_DELEG flavor of delegation.
>
> Add timespec64 fields to nfs4_cb_fattr and decode the timestamps into
> those. Vet those timestamps according to the delstid spec and update
> the inode attrs if necessary.
>
> Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
> Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
> ---
> fs/nfsd/nfs4callback.c | 42 +++++++++++++++++++--
> fs/nfsd/nfs4state.c | 99 +++++++++++++++++++++++++++++++++++++++++++-------
> fs/nfsd/nfs4xdr.c | 13 ++++++-
> fs/nfsd/nfsd.h | 2 +
> fs/nfsd/state.h | 2 +
> fs/nfsd/xdr4cb.h | 10 +++--
> include/linux/time64.h | 5 +++
> 7 files changed, 151 insertions(+), 22 deletions(-)
>
> diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
> index 776838bb83e6b707a4df76326cdc68f32daf1755..08245596289a960eb8b2e78df276544e7d3f4ff8 100644
> --- a/fs/nfsd/nfs4callback.c
> +++ b/fs/nfsd/nfs4callback.c
> @@ -42,6 +42,7 @@
> #include "trace.h"
> #include "xdr4cb.h"
> #include "xdr4.h"
> +#include "nfs4xdr_gen.h"
>
> #define NFSDDBG_FACILITY NFSDDBG_PROC
>
> @@ -93,12 +94,35 @@ static int decode_cb_fattr4(struct xdr_stream *xdr, uint32_t *bitmap,
> {
> fattr->ncf_cb_change = 0;
> fattr->ncf_cb_fsize = 0;
> + fattr->ncf_cb_atime.tv_sec = 0;
> + fattr->ncf_cb_atime.tv_nsec = 0;
> + fattr->ncf_cb_mtime.tv_sec = 0;
> + fattr->ncf_cb_mtime.tv_nsec = 0;
> +
> if (bitmap[0] & FATTR4_WORD0_CHANGE)
> if (xdr_stream_decode_u64(xdr, &fattr->ncf_cb_change) < 0)
> return -NFSERR_BAD_XDR;
> if (bitmap[0] & FATTR4_WORD0_SIZE)
> if (xdr_stream_decode_u64(xdr, &fattr->ncf_cb_fsize) < 0)
> return -NFSERR_BAD_XDR;
> + if (bitmap[2] & FATTR4_WORD2_TIME_DELEG_ACCESS) {
> + fattr4_time_deleg_access access;
> +
> + if (!xdrgen_decode_fattr4_time_deleg_access(xdr, &access))
> + return -NFSERR_BAD_XDR;
> + fattr->ncf_cb_atime.tv_sec = access.seconds;
> + fattr->ncf_cb_atime.tv_nsec = access.nseconds;
> +
> + }
> + if (bitmap[2] & FATTR4_WORD2_TIME_DELEG_MODIFY) {
> + fattr4_time_deleg_modify modify;
> +
> + if (!xdrgen_decode_fattr4_time_deleg_modify(xdr, &modify))
> + return -NFSERR_BAD_XDR;
> + fattr->ncf_cb_mtime.tv_sec = modify.seconds;
> + fattr->ncf_cb_mtime.tv_nsec = modify.nseconds;
> +
> + }
> return 0;
> }
>
> @@ -364,15 +388,21 @@ encode_cb_getattr4args(struct xdr_stream *xdr, struct nfs4_cb_compound_hdr *hdr,
> struct nfs4_delegation *dp = container_of(fattr, struct nfs4_delegation, dl_cb_fattr);
> struct knfsd_fh *fh = &dp->dl_stid.sc_file->fi_fhandle;
> struct nfs4_cb_fattr *ncf = &dp->dl_cb_fattr;
> - u32 bmap[1];
> + u32 bmap_size = 1;
> + u32 bmap[3];
>
> bmap[0] = FATTR4_WORD0_SIZE;
> if (!ncf->ncf_file_modified)
> bmap[0] |= FATTR4_WORD0_CHANGE;
>
> + if (deleg_attrs_deleg(dp->dl_type)) {
> + bmap[1] = 0;
> + bmap[2] = FATTR4_WORD2_TIME_DELEG_ACCESS | FATTR4_WORD2_TIME_DELEG_MODIFY;
> + bmap_size = 3;
> + }
> encode_nfs_cb_opnum4(xdr, OP_CB_GETATTR);
> encode_nfs_fh4(xdr, fh);
> - encode_bitmap4(xdr, bmap, ARRAY_SIZE(bmap));
> + encode_bitmap4(xdr, bmap, bmap_size);
> hdr->nops++;
> }
>
> @@ -597,7 +627,7 @@ static int nfs4_xdr_dec_cb_getattr(struct rpc_rqst *rqstp,
> struct nfs4_cb_compound_hdr hdr;
> int status;
> u32 bitmap[3] = {0};
> - u32 attrlen;
> + u32 attrlen, maxlen;
> struct nfs4_cb_fattr *ncf =
> container_of(cb, struct nfs4_cb_fattr, ncf_getattr);
>
> @@ -616,7 +646,11 @@ static int nfs4_xdr_dec_cb_getattr(struct rpc_rqst *rqstp,
> return -NFSERR_BAD_XDR;
> if (xdr_stream_decode_u32(xdr, &attrlen) < 0)
> return -NFSERR_BAD_XDR;
> - if (attrlen > (sizeof(ncf->ncf_cb_change) + sizeof(ncf->ncf_cb_fsize)))
> + maxlen = sizeof(ncf->ncf_cb_change) + sizeof(ncf->ncf_cb_fsize);
> + if (bitmap[2] != 0)
> + maxlen += (sizeof(ncf->ncf_cb_mtime.tv_sec) +
> + sizeof(ncf->ncf_cb_mtime.tv_nsec)) * 2;
> + if (attrlen > maxlen)
> return -NFSERR_BAD_XDR;
> status = decode_cb_fattr4(xdr, bitmap, ncf);
> return status;
> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
> index 62f9aeb159d0f2ab4d293bf5c0c56ad7b86eb9d6..2c8d2bb5261ad189c6dfb1c4050c23d8cf061325 100644
> --- a/fs/nfsd/nfs4state.c
> +++ b/fs/nfsd/nfs4state.c
> @@ -5803,13 +5803,14 @@ static struct nfs4_delegation *
> nfs4_set_delegation(struct nfsd4_open *open, struct nfs4_ol_stateid *stp,
> struct svc_fh *parent)
> {
> - int status = 0;
> + bool deleg_ts = open->op_deleg_want & OPEN4_SHARE_ACCESS_WANT_DELEG_TIMESTAMPS;
> struct nfs4_client *clp = stp->st_stid.sc_client;
> struct nfs4_file *fp = stp->st_stid.sc_file;
> struct nfs4_clnt_odstate *odstate = stp->st_clnt_odstate;
> struct nfs4_delegation *dp;
> struct nfsd_file *nf = NULL;
> struct file_lease *fl;
> + int status = 0;
> u32 dl_type;
>
> /*
> @@ -5834,7 +5835,7 @@ nfs4_set_delegation(struct nfsd4_open *open, struct nfs4_ol_stateid *stp,
> */
> if ((open->op_share_access & NFS4_SHARE_ACCESS_BOTH) == NFS4_SHARE_ACCESS_BOTH) {
> nf = find_rw_file(fp);
> - dl_type = OPEN_DELEGATE_WRITE;
> + dl_type = deleg_ts ? OPEN_DELEGATE_WRITE_ATTRS_DELEG : OPEN_DELEGATE_WRITE;
> }
>
> /*
> @@ -5843,7 +5844,7 @@ nfs4_set_delegation(struct nfsd4_open *open, struct nfs4_ol_stateid *stp,
> */
> if (!nf && (open->op_share_access & NFS4_SHARE_ACCESS_READ)) {
> nf = find_readable_file(fp);
> - dl_type = OPEN_DELEGATE_READ;
> + dl_type = deleg_ts ? OPEN_DELEGATE_READ_ATTRS_DELEG : OPEN_DELEGATE_READ;
> }
>
> if (!nf)
> @@ -6001,13 +6002,14 @@ static void
> nfs4_open_delegation(struct nfsd4_open *open, struct nfs4_ol_stateid *stp,
> struct svc_fh *currentfh)
> {
> - struct nfs4_delegation *dp;
> + bool deleg_ts = open->op_deleg_want & OPEN4_SHARE_ACCESS_WANT_DELEG_TIMESTAMPS;
> struct nfs4_openowner *oo = openowner(stp->st_stateowner);
> struct nfs4_client *clp = stp->st_stid.sc_client;
> struct svc_fh *parent = NULL;
> - int cb_up;
> - int status = 0;
> + struct nfs4_delegation *dp;
> struct kstat stat;
> + int status = 0;
> + int cb_up;
>
> cb_up = nfsd4_cb_channel_good(oo->oo_owner.so_client);
> open->op_recall = false;
> @@ -6048,12 +6050,14 @@ nfs4_open_delegation(struct nfsd4_open *open, struct nfs4_ol_stateid *stp,
> destroy_delegation(dp);
> goto out_no_deleg;
> }
> - open->op_delegate_type = OPEN_DELEGATE_WRITE;
> + open->op_delegate_type = deleg_ts ? OPEN_DELEGATE_WRITE_ATTRS_DELEG :
> + OPEN_DELEGATE_WRITE;
> dp->dl_cb_fattr.ncf_cur_fsize = stat.size;
> dp->dl_cb_fattr.ncf_initial_cinfo = nfsd4_change_attribute(&stat);
> trace_nfsd_deleg_write(&dp->dl_stid.sc_stateid);
> } else {
> - open->op_delegate_type = OPEN_DELEGATE_READ;
> + open->op_delegate_type = deleg_ts ? OPEN_DELEGATE_READ_ATTRS_DELEG :
> + OPEN_DELEGATE_READ;
> trace_nfsd_deleg_read(&dp->dl_stid.sc_stateid);
> }
> nfs4_put_stid(&dp->dl_stid);
> @@ -8887,6 +8891,78 @@ nfsd4_get_writestateid(struct nfsd4_compound_state *cstate,
> get_stateid(cstate, &u->write.wr_stateid);
> }
>
> +/**
> + * set_cb_time - vet and set the timespec for a cb_getattr update
> + * @cb: timestamp from the CB_GETATTR response
> + * @orig: original timestamp in the inode
> + * @now: current time
> + *
> + * Given a timestamp in a CB_GETATTR response, check it against the
> + * current timestamp in the inode and the current time. Returns true
> + * if the inode's timestamp needs to be updated, and false otherwise.
> + * @cb may also be changed if the timestamp needs to be clamped.
> + */
> +static bool set_cb_time(struct timespec64 *cb, const struct timespec64 *orig,
> + const struct timespec64 *now)
> +{
> +
> + /*
> + * "When the time presented is before the original time, then the
> + * update is ignored." Also no need to update if there is no change.
> + */
> + if (timespec64_compare(cb, orig) <= 0)
> + return false;
> +
> + /*
> + * "When the time presented is in the future, the server can either
> + * clamp the new time to the current time, or it may
> + * return NFS4ERR_DELAY to the client, allowing it to retry."
> + */
> + if (timespec64_compare(cb, now) > 0) {
> + /* clamp it */
> + *cb = *now;
> + }
> +
> + return true;
> +}
> +
> +static int cb_getattr_update_times(struct dentry *dentry, struct nfs4_delegation *dp)
> +{
> + struct inode *inode = d_inode(dentry);
> + struct timespec64 now = current_time(inode);
> + struct nfs4_cb_fattr *ncf = &dp->dl_cb_fattr;
> + struct iattr attrs = { };
> + int ret;
> +
> + if (deleg_attrs_deleg(dp->dl_type)) {
> + struct timespec64 atime = inode_get_atime(inode);
> + struct timespec64 mtime = inode_get_mtime(inode);
> +
> + attrs.ia_atime = ncf->ncf_cb_atime;
> + attrs.ia_mtime = ncf->ncf_cb_mtime;
> +
> + if (set_cb_time(&attrs.ia_atime, &atime, &now))
> + attrs.ia_valid |= ATTR_ATIME | ATTR_ATIME_SET;
> +
> + if (set_cb_time(&attrs.ia_mtime, &mtime, &now)) {
> + attrs.ia_valid |= ATTR_CTIME | ATTR_MTIME | ATTR_MTIME_SET;
> + attrs.ia_ctime = attrs.ia_mtime;
> + }
> + } else {
> + attrs.ia_valid |= ATTR_MTIME | ATTR_CTIME;
> + attrs.ia_mtime = attrs.ia_ctime = now;
> + }
> +
> + if (!attrs.ia_valid)
> + return 0;
> +
> + attrs.ia_valid |= ATTR_DELEG;
> + inode_lock(inode);
> + ret = notify_change(&nop_mnt_idmap, dentry, &attrs, NULL);
> + inode_unlock(inode);
> + return ret;
> +}
> +
> /**
> * nfsd4_deleg_getattr_conflict - Recall if GETATTR causes conflict
> * @rqstp: RPC transaction context
> @@ -8913,7 +8989,6 @@ nfsd4_deleg_getattr_conflict(struct svc_rqst *rqstp, struct dentry *dentry,
> struct file_lock_context *ctx;
> struct nfs4_delegation *dp = NULL;
> struct file_lease *fl;
> - struct iattr attrs;
> struct nfs4_cb_fattr *ncf;
> struct inode *inode = d_inode(dentry);
>
> @@ -8975,11 +9050,7 @@ nfsd4_deleg_getattr_conflict(struct svc_rqst *rqstp, struct dentry *dentry,
> * not update the file's metadata with the client's
> * modified size
> */
> - attrs.ia_mtime = attrs.ia_ctime = current_time(inode);
> - attrs.ia_valid = ATTR_MTIME | ATTR_CTIME | ATTR_DELEG;
> - inode_lock(inode);
> - err = notify_change(&nop_mnt_idmap, dentry, &attrs, NULL);
> - inode_unlock(inode);
> + err = cb_getattr_update_times(dentry, dp);
> if (err) {
> status = nfserrno(err);
> goto out_status;
> diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
> index 1c9d9349e4447c0078c7de0d533cf6278941679d..0e9f59f6be015bfa37893973f38fec880ff4c0b1 100644
> --- a/fs/nfsd/nfs4xdr.c
> +++ b/fs/nfsd/nfs4xdr.c
> @@ -3409,6 +3409,7 @@ static __be32 nfsd4_encode_fattr4_xattr_support(struct xdr_stream *xdr,
> #define NFSD_OA_SHARE_ACCESS_WANT (BIT(OPEN_ARGS_SHARE_ACCESS_WANT_ANY_DELEG) | \
> BIT(OPEN_ARGS_SHARE_ACCESS_WANT_NO_DELEG) | \
> BIT(OPEN_ARGS_SHARE_ACCESS_WANT_CANCEL) | \
> + BIT(OPEN_ARGS_SHARE_ACCESS_WANT_DELEG_TIMESTAMPS) | \
> BIT(OPEN_ARGS_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION))
>
> #define NFSD_OA_OPEN_CLAIM (BIT(OPEN_ARGS_OPEN_CLAIM_NULL) | \
> @@ -3602,7 +3603,11 @@ nfsd4_encode_fattr4(struct svc_rqst *rqstp, struct xdr_stream *xdr,
> if (status)
> goto out;
> }
> - if (attrmask[0] & (FATTR4_WORD0_CHANGE | FATTR4_WORD0_SIZE)) {
> + if ((attrmask[0] & (FATTR4_WORD0_CHANGE |
> + FATTR4_WORD0_SIZE)) ||
> + (attrmask[1] & (FATTR4_WORD1_TIME_ACCESS |
> + FATTR4_WORD1_TIME_MODIFY |
> + FATTR4_WORD1_TIME_METADATA))) {
> status = nfsd4_deleg_getattr_conflict(rqstp, dentry, &dp);
> if (status)
> goto out;
> @@ -3617,8 +3622,14 @@ nfsd4_encode_fattr4(struct svc_rqst *rqstp, struct xdr_stream *xdr,
> if (ncf->ncf_file_modified) {
> ++ncf->ncf_initial_cinfo;
> args.stat.size = ncf->ncf_cur_fsize;
> + if (!timespec64_is_epoch(&ncf->ncf_cb_mtime))
> + args.stat.mtime = ncf->ncf_cb_mtime;
> }
> args.change_attr = ncf->ncf_initial_cinfo;
> +
> + if (!timespec64_is_epoch(&ncf->ncf_cb_atime))
> + args.stat.atime = ncf->ncf_cb_atime;
> +
> nfs4_put_stid(&dp->dl_stid);
> } else {
> args.change_attr = nfsd4_change_attribute(&args.stat);
> diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h
> index 1955c8e9c4c793728fa75dd136cadc735245483f..004415651295891b3440f52a4c986e3a668a48cb 100644
> --- a/fs/nfsd/nfsd.h
> +++ b/fs/nfsd/nfsd.h
> @@ -459,6 +459,8 @@ enum {
> FATTR4_WORD2_MODE_UMASK | \
> NFSD4_2_SECURITY_ATTRS | \
> FATTR4_WORD2_XATTR_SUPPORT | \
> + FATTR4_WORD2_TIME_DELEG_ACCESS | \
> + FATTR4_WORD2_TIME_DELEG_MODIFY | \
This breaks 4.2 mounts for me (in latest nfsd-nexT). OPEN fails.
By setting these bits we tell the client that we support timestamp
delegation, but you haven't updated nfsd4_decode_share_access() to
understand NFS4_SHARE_WANT_DELEG_TIMESTAMPS in the 'share' flags for an
OPEN request. So the server responds with BADXDR to OPEN requests now.
Mounting with v4.1 still works.
NeilBrown
> FATTR4_WORD2_OPEN_ARGUMENTS)
>
> extern const u32 nfsd_suppattrs[3][3];
> diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
> index 9d0e844515aa6ea0ec62f2b538ecc2c6a5e34652..6351e6eca7cc63ccf82a3a081cef39042d52f4e9 100644
> --- a/fs/nfsd/state.h
> +++ b/fs/nfsd/state.h
> @@ -142,6 +142,8 @@ struct nfs4_cb_fattr {
> /* from CB_GETATTR reply */
> u64 ncf_cb_change;
> u64 ncf_cb_fsize;
> + struct timespec64 ncf_cb_mtime;
> + struct timespec64 ncf_cb_atime;
>
> unsigned long ncf_cb_flags;
> bool ncf_file_modified;
> diff --git a/fs/nfsd/xdr4cb.h b/fs/nfsd/xdr4cb.h
> index e8b00309c449fe2667f7d48cda88ec0cff924f93..f1a315cd31b74f73f1d52702ae7b5c93d51ddf82 100644
> --- a/fs/nfsd/xdr4cb.h
> +++ b/fs/nfsd/xdr4cb.h
> @@ -59,16 +59,20 @@
> * 1: CB_GETATTR opcode (32-bit)
> * N: file_handle
> * 1: number of entry in attribute array (32-bit)
> - * 1: entry 0 in attribute array (32-bit)
> + * 3: entry 0-2 in attribute array (32-bit * 3)
> */
> #define NFS4_enc_cb_getattr_sz (cb_compound_enc_hdr_sz + \
> cb_sequence_enc_sz + \
> - 1 + enc_nfs4_fh_sz + 1 + 1)
> + 1 + enc_nfs4_fh_sz + 1 + 3)
> /*
> * 4: fattr_bitmap_maxsz
> * 1: attribute array len
> * 2: change attr (64-bit)
> * 2: size (64-bit)
> + * 2: atime.seconds (64-bit)
> + * 1: atime.nanoseconds (32-bit)
> + * 2: mtime.seconds (64-bit)
> + * 1: mtime.nanoseconds (32-bit)
> */
> #define NFS4_dec_cb_getattr_sz (cb_compound_dec_hdr_sz + \
> - cb_sequence_dec_sz + 4 + 1 + 2 + 2 + op_dec_sz)
> + cb_sequence_dec_sz + 4 + 1 + 2 + 2 + 2 + 1 + 2 + 1 + op_dec_sz)
> diff --git a/include/linux/time64.h b/include/linux/time64.h
> index f1bcea8c124a361b6c1e3c98ef915840c22a8413..9934331c7b86b7fb981c7aec0494ac2f5e72977e 100644
> --- a/include/linux/time64.h
> +++ b/include/linux/time64.h
> @@ -49,6 +49,11 @@ static inline int timespec64_equal(const struct timespec64 *a,
> return (a->tv_sec == b->tv_sec) && (a->tv_nsec == b->tv_nsec);
> }
>
> +static inline bool timespec64_is_epoch(const struct timespec64 *ts)
> +{
> + return ts->tv_sec == 0 && ts->tv_nsec == 0;
> +}
> +
> /*
> * lhs < rhs: return <0
> * lhs == rhs: return 0
>
> --
> 2.47.0
>
>
>
