On 9/4/25 11:54 AM, Chuck Lever wrote:
> On 9/3/25 3:34 PM, Sergey Bashirov wrote:
>> When the block/scsi layout server is recovering from a reboot and is in a
>> grace period, any operation that may result in deletion or reallocation of
>> block extents should not be allowed. See RFC 8881, section 18.43.3.
>>
>> If multiple clients write data to the same file, rebooting the server
>> during writing can result in the file corruption. Observed this behavior
>> while testing pNFS block volume setup.
>>
>> Co-developed-by: Konstantin Evtushenko <koevtushenko@xxxxxxxxxx>
>> Signed-off-by: Konstantin Evtushenko <koevtushenko@xxxxxxxxxx>
>> Signed-off-by: Sergey Bashirov <sergeybashirov@xxxxxxxxx>
>> ---
>> Changes in v2:
>> - Push down the check to layout driver level
>>
>> fs/nfsd/blocklayout.c | 8 +++++++-
>> fs/nfsd/flexfilelayout.c | 2 +-
>> fs/nfsd/nfs4proc.c | 3 ++-
>> fs/nfsd/pnfs.h | 2 +-
>> 4 files changed, 11 insertions(+), 4 deletions(-)
>>
>> diff --git a/fs/nfsd/blocklayout.c b/fs/nfsd/blocklayout.c
>> index 0822d8a119c6..1fbc5bbde07f 100644
>> --- a/fs/nfsd/blocklayout.c
>> +++ b/fs/nfsd/blocklayout.c
>> @@ -19,7 +19,7 @@
>>
>> static __be32
>> nfsd4_block_proc_layoutget(struct inode *inode, const struct svc_fh *fhp,
>> - struct nfsd4_layoutget *args)
>> + struct nfsd4_layoutget *args, bool in_grace)
>> {
>> struct nfsd4_layout_seg *seg = &args->lg_seg;
>> struct super_block *sb = inode->i_sb;
>> @@ -34,6 +34,9 @@ nfsd4_block_proc_layoutget(struct inode *inode, const struct svc_fh *fhp,
>> goto out_layoutunavailable;
>> }
>>
>> + if (in_grace)
>> + goto out_grace;
>
> Taste/style nit:
>
> I prefer that the controlling svc_rqst is passed to ->proc_layoutget,
> rather than passing a boolean. The ff layout can just ignore that
> new parameter, and the block layout can deref the network namespace and
> do the locks_in_grace check.
Never mind. I will take v2 as is and fix this up myself.
>> +
>> /*
>> * Some clients barf on non-zero block numbers for NONE or INVALID
>> * layouts, so make sure to zero the whole structure.
>> @@ -111,6 +114,9 @@ nfsd4_block_proc_layoutget(struct inode *inode, const struct svc_fh *fhp,
>> out_layoutunavailable:
>> seg->length = 0;
>> return nfserr_layoutunavailable;
>> +out_grace:
>> + seg->length = 0;
>> + return nfserr_grace;
>> }
>>
>> static __be32
>> diff --git a/fs/nfsd/flexfilelayout.c b/fs/nfsd/flexfilelayout.c
>> index 3ca5304440ff..274a1e9bb596 100644
>> --- a/fs/nfsd/flexfilelayout.c
>> +++ b/fs/nfsd/flexfilelayout.c
>> @@ -21,7 +21,7 @@
>>
>> static __be32
>> nfsd4_ff_proc_layoutget(struct inode *inode, const struct svc_fh *fhp,
>> - struct nfsd4_layoutget *args)
>> + struct nfsd4_layoutget *args, bool in_grace)
>> {
>> struct nfsd4_layout_seg *seg = &args->lg_seg;
>> u32 device_generation = 0;
>> diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
>> index d7c58aa64f06..5d1d343a4e23 100644
>> --- a/fs/nfsd/nfs4proc.c
>> +++ b/fs/nfsd/nfs4proc.c
>> @@ -2435,6 +2435,7 @@ static __be32
>> nfsd4_layoutget(struct svc_rqst *rqstp,
>> struct nfsd4_compound_state *cstate, union nfsd4_op_u *u)
>> {
>> + struct net *net = SVC_NET(rqstp);
>> struct nfsd4_layoutget *lgp = &u->layoutget;
>> struct svc_fh *current_fh = &cstate->current_fh;
>> const struct nfsd4_layout_ops *ops;
>> @@ -2498,7 +2499,7 @@ nfsd4_layoutget(struct svc_rqst *rqstp,
>> goto out_put_stid;
>>
>> nfserr = ops->proc_layoutget(d_inode(current_fh->fh_dentry),
>> - current_fh, lgp);
>> + current_fh, lgp, locks_in_grace(net));
>> if (nfserr)
>> goto out_put_stid;
>>
>> diff --git a/fs/nfsd/pnfs.h b/fs/nfsd/pnfs.h
>> index dfd411d1f363..61c2528ef077 100644
>> --- a/fs/nfsd/pnfs.h
>> +++ b/fs/nfsd/pnfs.h
>> @@ -30,7 +30,7 @@ struct nfsd4_layout_ops {
>> const struct nfsd4_getdeviceinfo *gdevp);
>>
>> __be32 (*proc_layoutget)(struct inode *, const struct svc_fh *fhp,
>> - struct nfsd4_layoutget *lgp);
>> + struct nfsd4_layoutget *lgp, bool in_grace);
>> __be32 (*encode_layoutget)(struct xdr_stream *xdr,
>> const struct nfsd4_layoutget *lgp);
>>
>
>
--
Chuck Lever
