Return-Path: linux-nfs-owner@vger.kernel.org Received: from mx12.netapp.com ([216.240.18.77]:8236 "EHLO mx12.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933812AbaH0TVc (ORCPT ); Wed, 27 Aug 2014 15:21:32 -0400 Message-ID: <53FE2FB2.3040606@Netapp.com> Date: Wed, 27 Aug 2014 15:21:22 -0400 From: Anna Schumaker MIME-Version: 1.0 To: "J. Bruce Fields" , CC: Subject: Re: [PATCH 3/3] NFSD: Implement SEEK References: <1409152678-7806-1-git-send-email-bjschuma@netapp.com> <1409152678-7806-4-git-send-email-bjschuma@netapp.com> <20140827190940.GD13910@fieldses.org> In-Reply-To: <20140827190940.GD13910@fieldses.org> Content-Type: text/plain; charset="utf-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: On 08/27/2014 03:09 PM, J. Bruce Fields wrote: > On Wed, Aug 27, 2014 at 11:17:58AM -0400, bjschuma@netapp.com wrote: >> From: Anna Schumaker >> >> This patch adds server support for the NFS v4.2 operation SEEK, which >> returns the position of the next hole or data segment in a file. This >> operation is off by default, and needs CONFIG_NFSD_V4_2_SEEK=y to be >> compiled. >> >> Signed-off-by: Anna Schumaker >> --- >> fs/nfsd/Kconfig | 12 ++++++++++++ >> fs/nfsd/nfs4proc.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++ >> fs/nfsd/nfs4xdr.c | 45 +++++++++++++++++++++++++++++++++++++++++++++ >> fs/nfsd/xdr4.h | 14 ++++++++++++++ >> include/linux/nfs4.h | 5 +++++ >> 5 files changed, 123 insertions(+) >> >> diff --git a/fs/nfsd/Kconfig b/fs/nfsd/Kconfig >> index f994e75..804b20a 100644 >> --- a/fs/nfsd/Kconfig >> +++ b/fs/nfsd/Kconfig >> @@ -81,6 +81,18 @@ config NFSD_V4 >> >> If unsure, say N. >> >> +config NFSD_V4_2_SEEK >> + bool "Enable SEEK support for the NFS v4.2 server" >> + depends on NFSD_V4 >> + help >> + Say Y here if you want to enable support for the NFS v4.2 operation >> + SEEK, which adds in SEEK_HOLE and SEEK_DATA support. >> + >> + WARNING: there is still a chance of backwards-incompatible protocol >> + changes. This feature is targeted at developers and testers only. > > I think now that we should instead confirm with the working group that > backwards-incompatible changes are done, and skip this warning. > > I'll remove it in the labeled NFS case, which we've decided is "done" > even if the rest of the 4.2 draft isn't. > > I also wonder if we should ditch these configuration options, or keep > them only temporarily. It's not much code, so I think the only reason > to allow configuring it out is to temporarily protect people from > immature code. I was expecting them to be temporary, and to get removed when the draft becomes an RFC. > >> + >> + If unsure, say N. >> + >> config NFSD_V4_SECURITY_LABEL >> bool "Provide Security Label support for NFSv4 server" >> depends on NFSD_V4 && SECURITY >> diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c >> index 5e0dc52..f555eb2 100644 >> --- a/fs/nfsd/nfs4proc.c >> +++ b/fs/nfsd/nfs4proc.c >> @@ -1013,6 +1013,45 @@ nfsd4_write(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, >> return status; >> } >> >> +#ifdef CONFIG_NFSD_V4_2_SEEK >> +static __be32 >> +nfsd4_seek(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, >> + struct nfsd4_seek *seek) >> +{ >> + struct file *file; >> + __be32 status = nfs_ok; >> + >> + status = nfs4_preprocess_stateid_op(SVC_NET(rqstp), cstate, >> + &seek->seek_stateid, >> + RD_STATE | WR_STATE, &file); > > I think that should be just RD_STATE. I was trying to cover the case where an application does: open(WRITE); seek(HOLE); write("blah"); I can change the code if that's not the way people use SEEK_HOLE / SEEK_DATA ... Anna > > --b. > > >> + if (status) { >> + dprintk("NFSD: nfsd4_seek: couldn't process stateid!\n"); >> + return status; >> + } >> + >> + switch (seek->seek_whence) { >> + case NFS4_CONTENT_DATA: >> + seek->seek_pos = vfs_llseek(file, seek->seek_offset, SEEK_DATA); >> + break; >> + case NFS4_CONTENT_HOLE: >> + seek->seek_pos = vfs_llseek(file, seek->seek_offset, SEEK_HOLE); >> + break; >> + default: >> + status = nfserr_union_notsupp; >> + goto out; >> + } >> + >> + if (seek->seek_pos < 0) >> + status = nfserrno(seek->seek_pos); >> + else if (seek->seek_pos >= i_size_read(file_inode(file))) >> + seek->seek_eof = true; >> + >> +out: >> + fput(file); >> + return status; >> +} >> +#endif /* CONFIG_NFSD_V4_2_SEEK */ >> + >> /* This routine never returns NFS_OK! If there are no other errors, it >> * will return NFSERR_SAME or NFSERR_NOT_SAME depending on whether the >> * attributes matched. VERIFY is implemented by mapping NFSERR_SAME >> @@ -1881,6 +1920,14 @@ static struct nfsd4_operation nfsd4_ops[] = { >> .op_get_currentstateid = (stateid_getter)nfsd4_get_freestateid, >> .op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize, >> }, >> + >> + /* NFSv4.2 operations */ >> +#ifdef CONFIG_NFSD_V4_2_SEEK >> + [OP_SEEK] = { >> + .op_func = (nfsd4op_func)nfsd4_seek, >> + .op_name = "OP_SEEK", >> + }, >> +#endif /* CONFIG_NFSD_V4_2_SEEK */ >> }; >> >> int nfsd4_max_reply(struct svc_rqst *rqstp, struct nfsd4_op *op) >> diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c >> index 94dde7b..5bedeb3 100644 >> --- a/fs/nfsd/nfs4xdr.c >> +++ b/fs/nfsd/nfs4xdr.c >> @@ -1520,6 +1520,24 @@ static __be32 nfsd4_decode_reclaim_complete(struct nfsd4_compoundargs *argp, str >> DECODE_TAIL; >> } >> >> +#ifdef CONFIG_NFSD_V4_2_SEEK >> +static __be32 >> +nfsd4_decode_seek(struct nfsd4_compoundargs *argp, struct nfsd4_seek *seek) >> +{ >> + DECODE_HEAD; >> + >> + status = nfsd4_decode_stateid(argp, &seek->seek_stateid); >> + if (status) >> + return status; >> + >> + READ_BUF(12); >> + p = xdr_decode_hyper(p, &seek->seek_offset); >> + seek->seek_whence = be32_to_cpup(p); >> + >> + DECODE_TAIL; >> +} >> +#endif /* CONFIG_NFSD_V4_2_SEEK */ >> + >> static __be32 >> nfsd4_decode_noop(struct nfsd4_compoundargs *argp, void *p) >> { >> @@ -1605,7 +1623,11 @@ static nfsd4_dec nfsd4_dec_ops[] = { >> [OP_OFFLOAD_CANCEL] = (nfsd4_dec)nfsd4_decode_notsupp, >> [OP_OFFLOAD_STATUS] = (nfsd4_dec)nfsd4_decode_notsupp, >> [OP_READ_PLUS] = (nfsd4_dec)nfsd4_decode_notsupp, >> +#ifdef CONFIG_NFSD_V4_2_SEEK >> + [OP_SEEK] = (nfsd4_dec)nfsd4_decode_seek, >> +#else >> [OP_SEEK] = (nfsd4_dec)nfsd4_decode_notsupp, >> +#endif /* CONFIG_NFSD_V4_2_SEEK */ >> [OP_WRITE_SAME] = (nfsd4_dec)nfsd4_decode_notsupp, >> }; >> >> @@ -3764,6 +3786,24 @@ nfsd4_encode_test_stateid(struct nfsd4_compoundres *resp, __be32 nfserr, >> return nfserr; >> } >> >> +#ifdef CONFIG_NFSD_V4_2_SEEK >> +static __be32 >> +nfsd4_encode_seek(struct nfsd4_compoundres *resp, __be32 nfserr, >> + struct nfsd4_seek *seek) >> +{ >> + __be32 *p; >> + >> + if (nfserr) >> + return nfserr; >> + >> + p = xdr_reserve_space(&resp->xdr, 12); >> + *p++ = cpu_to_be32(seek->seek_eof); >> + p = xdr_encode_hyper(p, seek->seek_pos); >> + >> + return nfserr; >> +} >> +#endif /* CONFIG_NFSD_V4_2_SEEK */ >> + >> static __be32 >> nfsd4_encode_noop(struct nfsd4_compoundres *resp, __be32 nfserr, void *p) >> { >> @@ -3848,8 +3888,13 @@ static nfsd4_enc nfsd4_enc_ops[] = { >> [OP_OFFLOAD_CANCEL] = (nfsd4_enc)nfsd4_encode_noop, >> [OP_OFFLOAD_STATUS] = (nfsd4_enc)nfsd4_encode_noop, >> [OP_READ_PLUS] = (nfsd4_enc)nfsd4_encode_noop, >> +#ifdef CONFIG_NFSD_V4_2_SEEK >> + [OP_SEEK] = (nfsd4_enc)nfsd4_encode_seek, >> +#else >> [OP_SEEK] = (nfsd4_enc)nfsd4_encode_noop, >> +#endif /* CONFIG_NFSD_V4_2_SEEK */ >> [OP_WRITE_SAME] = (nfsd4_enc)nfsd4_encode_noop, >> + [OP_IO_ADVISE] = (nfsd4_enc)nfsd4_encode_noop, >> }; >> >> /* >> diff --git a/fs/nfsd/xdr4.h b/fs/nfsd/xdr4.h >> index 465e779..5720e94 100644 >> --- a/fs/nfsd/xdr4.h >> +++ b/fs/nfsd/xdr4.h >> @@ -428,6 +428,17 @@ struct nfsd4_reclaim_complete { >> u32 rca_one_fs; >> }; >> >> +struct nfsd4_seek { >> + /* request */ >> + stateid_t seek_stateid; >> + loff_t seek_offset; >> + u32 seek_whence; >> + >> + /* response */ >> + u32 seek_eof; >> + loff_t seek_pos; >> +}; >> + >> struct nfsd4_op { >> int opnum; >> __be32 status; >> @@ -473,6 +484,9 @@ struct nfsd4_op { >> struct nfsd4_reclaim_complete reclaim_complete; >> struct nfsd4_test_stateid test_stateid; >> struct nfsd4_free_stateid free_stateid; >> + >> + /* NFSv4.2 */ >> + struct nfsd4_seek seek; >> } u; >> struct nfs4_replay * replay; >> }; >> diff --git a/include/linux/nfs4.h b/include/linux/nfs4.h >> index cf38224..026b0c0 100644 >> --- a/include/linux/nfs4.h >> +++ b/include/linux/nfs4.h >> @@ -550,4 +550,9 @@ struct nfs4_deviceid { >> char data[NFS4_DEVICEID4_SIZE]; >> }; >> >> +enum data_content4 { >> + NFS4_CONTENT_DATA = 0, >> + NFS4_CONTENT_HOLE = 1, >> +}; >> + >> #endif >> -- >> 2.1.0 >>