> On Dec 17, 2021, at 4:50 PM, trondmy@xxxxxxxxxx wrote:
>
> From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
>
> Allow knfsd to request weak cache consistency attributes on files that
> have delegations and/or have up to date attribute caches.
>
> Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
> Signed-off-by: Lance Shelton <lance.shelton@xxxxxxxxxxxxxxx>
> Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
This one does not apply to v5.16-rc. Please rebase this series
and resend.
More below:
> ---
> fs/nfs/export.c | 24 ++++++++++++
> fs/nfsd/nfs3xdr.c | 83 +++++++++++++++++++++++++++-------------
> fs/nfsd/nfs4xdr.c | 6 +--
> fs/nfsd/vfs.c | 14 +++++++
> fs/nfsd/vfs.h | 5 ++-
> include/linux/exportfs.h | 3 ++
> 6 files changed, 103 insertions(+), 32 deletions(-)
>
> diff --git a/fs/nfs/export.c b/fs/nfs/export.c
> index 171c424cb6d5..967f8902c49b 100644
> --- a/fs/nfs/export.c
> +++ b/fs/nfs/export.c
> @@ -151,10 +151,34 @@ static u64 nfs_fetch_iversion(struct inode *inode)
> return inode_peek_iversion_raw(inode);
> }
>
> +static int nfs_exp_getattr(struct path *path, struct kstat *stat, bool force)
> +{
> + const unsigned long check_valid =
> + NFS_INO_INVALID_CHANGE | NFS_INO_INVALID_ATIME |
> + NFS_INO_INVALID_CTIME | NFS_INO_INVALID_MTIME |
> + NFS_INO_INVALID_SIZE | /* NFS_INO_INVALID_BLOCKS | */
> + NFS_INO_INVALID_OTHER | NFS_INO_INVALID_NLINK;
> + struct inode *inode = d_inode(path->dentry);
> + int flags = force ? AT_STATX_SYNC_AS_STAT : AT_STATX_DONT_SYNC;
> + int ret, ret2 = 0;
> +
> + if (!force && nfs_check_cache_invalid(inode, check_valid))
> + ret2 = -EAGAIN;
> + ret = vfs_getattr(path, stat, STATX_BASIC_STATS & ~STATX_BLOCKS, flags);
> + if (ret < 0)
> + return ret;
> + stat->blocks = nfs_calc_block_size(stat->size);
> + if (S_ISDIR(inode->i_mode))
> + stat->blksize = NFS_SERVER(inode)->dtsize;
> + stat->result_mask |= STATX_BLOCKS;
> + return ret2;
> +}
> +
> const struct export_operations nfs_export_ops = {
> .encode_fh = nfs_encode_fh,
> .fh_to_dentry = nfs_fh_to_dentry,
> .get_parent = nfs_get_parent,
> + .getattr = nfs_exp_getattr,
> .fetch_iversion = nfs_fetch_iversion,
> .flags = EXPORT_OP_NOWCC|EXPORT_OP_NOSUBTREECHK|
> EXPORT_OP_CLOSE_BEFORE_UNLINK|EXPORT_OP_REMOTE_FS|
> diff --git a/fs/nfsd/nfs3xdr.c b/fs/nfsd/nfs3xdr.c
> index 0a5ebc52e6a9..81b6cf228517 100644
> --- a/fs/nfsd/nfs3xdr.c
> +++ b/fs/nfsd/nfs3xdr.c
> @@ -415,21 +415,14 @@ svcxdr_encode_pre_op_attr(struct xdr_stream *xdr, const struct svc_fh *fhp)
> return svcxdr_encode_wcc_attr(xdr, fhp);
> }
>
> -/**
> - * svcxdr_encode_post_op_attr - Encode NFSv3 post-op attributes
> - * @rqstp: Context of a completed RPC transaction
> - * @xdr: XDR stream
> - * @fhp: File handle to encode
> - *
> - * Return values:
> - * %false: Send buffer space was exhausted
> - * %true: Success
> - */
> -bool
> -svcxdr_encode_post_op_attr(struct svc_rqst *rqstp, struct xdr_stream *xdr,
> - const struct svc_fh *fhp)
> +static bool
> +__svcxdr_encode_post_op_attr(struct svc_rqst *rqstp, struct xdr_stream *xdr,
> + const struct svc_fh *fhp, bool force)
> {
> struct dentry *dentry = fhp->fh_dentry;
> + struct path path = {
> + .dentry = dentry,
> + };
> struct kstat stat;
>
> /*
> @@ -437,9 +430,10 @@ svcxdr_encode_post_op_attr(struct svc_rqst *rqstp, struct xdr_stream *xdr,
> * stale file handle. In this case, no attributes are
> * returned.
> */
> - if (fhp->fh_no_wcc || !dentry || !d_really_is_positive(dentry))
> + if (!dentry || !d_really_is_positive(dentry))
> goto no_post_op_attrs;
> - if (fh_getattr(fhp, &stat) != nfs_ok)
> + path.mnt = fhp->fh_export->ex_path.mnt;
> + if (nfsd_getattr(&path, &stat, force) != nfs_ok)
> goto no_post_op_attrs;
>
> if (xdr_stream_encode_item_present(xdr) < 0)
> @@ -454,6 +448,31 @@ svcxdr_encode_post_op_attr(struct svc_rqst *rqstp, struct xdr_stream *xdr,
> return xdr_stream_encode_item_absent(xdr) > 0;
> }
>
> +/**
> + * svcxdr_encode_post_op_attr - Encode NFSv3 post-op attributes
> + * @rqstp: Context of a completed RPC transaction
> + * @xdr: XDR stream
> + * @fhp: File handle to encode
> + *
> + * Return values:
> + * %false: Send buffer space was exhausted
> + * %true: Success
> + */
> +bool
> +svcxdr_encode_post_op_attr(struct svc_rqst *rqstp, struct xdr_stream *xdr,
> + const struct svc_fh *fhp)
> +{
> + return __svcxdr_encode_post_op_attr(rqstp, xdr, fhp, true);
> +}
> +
> +static bool
> +svcxdr_encode_post_op_attr_opportunistic(struct svc_rqst *rqstp,
> + struct xdr_stream *xdr,
> + const struct svc_fh *fhp)
> +{
> + return __svcxdr_encode_post_op_attr(rqstp, xdr, fhp, !fhp->fh_no_wcc);
> +}
I don't quite understand the need for splitting encode_post_op_attr.
At the least, more commentary in the patch description would help.
For now, I will study this and get back to you.
> +
> /*
> * Encode weak cache consistency data
> */
> @@ -481,7 +500,7 @@ svcxdr_encode_wcc_data(struct svc_rqst *rqstp, struct xdr_stream *xdr,
> neither:
> if (xdr_stream_encode_item_absent(xdr) < 0)
> return false;
> - if (!svcxdr_encode_post_op_attr(rqstp, xdr, fhp))
> + if (!svcxdr_encode_post_op_attr_opportunistic(rqstp, xdr, fhp))
> return false;
>
> return true;
> @@ -879,11 +898,13 @@ int nfs3svc_encode_lookupres(struct svc_rqst *rqstp, __be32 *p)
> return 0;
> if (!svcxdr_encode_post_op_attr(rqstp, xdr, &resp->fh))
> return 0;
> - if (!svcxdr_encode_post_op_attr(rqstp, xdr, &resp->dirfh))
> + if (!svcxdr_encode_post_op_attr_opportunistic(rqstp, xdr,
> + &resp->dirfh))
> return 0;
> break;
> default:
> - if (!svcxdr_encode_post_op_attr(rqstp, xdr, &resp->dirfh))
> + if (!svcxdr_encode_post_op_attr_opportunistic(rqstp, xdr,
> + &resp->dirfh))
> return 0;
> }
>
> @@ -901,13 +922,15 @@ nfs3svc_encode_accessres(struct svc_rqst *rqstp, __be32 *p)
> return 0;
> switch (resp->status) {
> case nfs_ok:
> - if (!svcxdr_encode_post_op_attr(rqstp, xdr, &resp->fh))
> + if (!svcxdr_encode_post_op_attr_opportunistic(rqstp, xdr,
> + &resp->fh))
> return 0;
> if (xdr_stream_encode_u32(xdr, resp->access) < 0)
> return 0;
> break;
> default:
> - if (!svcxdr_encode_post_op_attr(rqstp, xdr, &resp->fh))
> + if (!svcxdr_encode_post_op_attr_opportunistic(rqstp, xdr,
> + &resp->fh))
> return 0;
> }
>
> @@ -926,7 +949,8 @@ nfs3svc_encode_readlinkres(struct svc_rqst *rqstp, __be32 *p)
> return 0;
> switch (resp->status) {
> case nfs_ok:
> - if (!svcxdr_encode_post_op_attr(rqstp, xdr, &resp->fh))
> + if (!svcxdr_encode_post_op_attr_opportunistic(rqstp, xdr,
> + &resp->fh))
> return 0;
> if (xdr_stream_encode_u32(xdr, resp->len) < 0)
> return 0;
> @@ -935,7 +959,8 @@ nfs3svc_encode_readlinkres(struct svc_rqst *rqstp, __be32 *p)
> return 0;
> break;
> default:
> - if (!svcxdr_encode_post_op_attr(rqstp, xdr, &resp->fh))
> + if (!svcxdr_encode_post_op_attr_opportunistic(rqstp, xdr,
> + &resp->fh))
> return 0;
> }
>
> @@ -954,7 +979,8 @@ nfs3svc_encode_readres(struct svc_rqst *rqstp, __be32 *p)
> return 0;
> switch (resp->status) {
> case nfs_ok:
> - if (!svcxdr_encode_post_op_attr(rqstp, xdr, &resp->fh))
> + if (!svcxdr_encode_post_op_attr_opportunistic(rqstp, xdr,
> + &resp->fh))
> return 0;
> if (xdr_stream_encode_u32(xdr, resp->count) < 0)
> return 0;
> @@ -968,7 +994,8 @@ nfs3svc_encode_readres(struct svc_rqst *rqstp, __be32 *p)
> return 0;
> break;
> default:
> - if (!svcxdr_encode_post_op_attr(rqstp, xdr, &resp->fh))
> + if (!svcxdr_encode_post_op_attr_opportunistic(rqstp, xdr,
> + &resp->fh))
> return 0;
> }
>
> @@ -1065,7 +1092,8 @@ nfs3svc_encode_readdirres(struct svc_rqst *rqstp, __be32 *p)
> return 0;
> switch (resp->status) {
> case nfs_ok:
> - if (!svcxdr_encode_post_op_attr(rqstp, xdr, &resp->fh))
> + if (!svcxdr_encode_post_op_attr_opportunistic(rqstp, xdr,
> + &resp->fh))
> return 0;
> if (!svcxdr_encode_cookieverf3(xdr, resp->verf))
> return 0;
> @@ -1077,7 +1105,8 @@ nfs3svc_encode_readdirres(struct svc_rqst *rqstp, __be32 *p)
> return 0;
> break;
> default:
> - if (!svcxdr_encode_post_op_attr(rqstp, xdr, &resp->fh))
> + if (!svcxdr_encode_post_op_attr_opportunistic(rqstp, xdr,
> + &resp->fh))
> return 0;
> }
>
> @@ -1221,7 +1250,7 @@ svcxdr_encode_entry3_plus(struct nfsd3_readdirres *resp, const char *name,
> if (compose_entry_fh(resp, fhp, name, namlen, ino) != nfs_ok)
> goto out_noattrs;
>
> - if (!svcxdr_encode_post_op_attr(resp->rqstp, xdr, fhp))
> + if (!svcxdr_encode_post_op_attr_opportunistic(resp->rqstp, xdr, fhp))
> goto out;
> if (!svcxdr_encode_post_op_fh3(xdr, fhp))
> goto out;
> diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
> index 7abeccb975b2..e14af0383b70 100644
> --- a/fs/nfsd/nfs4xdr.c
> +++ b/fs/nfsd/nfs4xdr.c
> @@ -2865,9 +2865,9 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
> goto out;
> }
>
> - err = vfs_getattr(&path, &stat, STATX_BASIC_STATS, AT_STATX_SYNC_AS_STAT);
> - if (err)
> - goto out_nfserr;
> + status = nfsd_getattr(&path, &stat, true);
> + if (status)
> + goto out;
> if ((bmval0 & (FATTR4_WORD0_FILES_AVAIL | FATTR4_WORD0_FILES_FREE |
> FATTR4_WORD0_FILES_TOTAL | FATTR4_WORD0_MAXNAME)) ||
> (bmval1 & (FATTR4_WORD1_SPACE_AVAIL | FATTR4_WORD1_SPACE_FREE |
> diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
> index a90cc08211a3..4d57befdac6e 100644
> --- a/fs/nfsd/vfs.c
> +++ b/fs/nfsd/vfs.c
> @@ -2412,3 +2412,17 @@ nfsd_permission(struct svc_rqst *rqstp, struct svc_export *exp,
>
> return err? nfserrno(err) : 0;
> }
> +
> +
> +__be32
> +nfsd_getattr(struct path *p, struct kstat *stat, bool force)
> +{
> + const struct export_operations *ops = p->dentry->d_sb->s_export_op;
> + int err;
> +
> + if (ops->getattr)
> + err = ops->getattr(p, stat, force);
> + else
> + err = vfs_getattr(p, stat, STATX_BASIC_STATS, AT_STATX_SYNC_AS_STAT);
> + return err ? nfserrno(err) : 0;
> +}
Please add nfsd_getattr() in a separate patch ("Refactor:").
And please include a kerneldoc comment for it.
> diff --git a/fs/nfsd/vfs.h b/fs/nfsd/vfs.h
> index b21b76e6b9a8..6edae1b9a96e 100644
> --- a/fs/nfsd/vfs.h
> +++ b/fs/nfsd/vfs.h
> @@ -132,6 +132,8 @@ __be32 nfsd_statfs(struct svc_rqst *, struct svc_fh *,
> __be32 nfsd_permission(struct svc_rqst *, struct svc_export *,
> struct dentry *, int);
>
> +__be32 nfsd_getattr(struct path *p, struct kstat *, bool);
> +
> static inline int fh_want_write(struct svc_fh *fh)
> {
> int ret;
> @@ -156,8 +158,7 @@ static inline __be32 fh_getattr(const struct svc_fh *fh, struct kstat *stat)
> {
> struct path p = {.mnt = fh->fh_export->ex_path.mnt,
> .dentry = fh->fh_dentry};
> - return nfserrno(vfs_getattr(&p, stat, STATX_BASIC_STATS,
> - AT_STATX_SYNC_AS_STAT));
> + return nfsd_getattr(&p, stat, true);
> }
>
> static inline int nfsd_create_is_exclusive(int createmode)
> diff --git a/include/linux/exportfs.h b/include/linux/exportfs.h
> index 3260fe714846..58f36022787e 100644
> --- a/include/linux/exportfs.h
> +++ b/include/linux/exportfs.h
> @@ -10,6 +10,8 @@ struct inode;
> struct iomap;
> struct super_block;
> struct vfsmount;
> +struct path;
> +struct kstat;
>
> /* limit the handle size to NFSv4 handle size now */
> #define MAX_HANDLE_SZ 128
> @@ -224,6 +226,7 @@ struct export_operations {
> #define EXPORT_OP_SYNC_LOCKS (0x20) /* Filesystem can't do
> asychronous blocking locks */
> unsigned long flags;
> + int (*getattr)(struct path *, struct kstat *, bool);
> };
>
> extern int exportfs_encode_inode_fh(struct inode *inode, struct fid *fid,
> --
> 2.33.1
>
--
Chuck Lever
