Return-Path: linux-nfs-owner@vger.kernel.org Received: from fieldses.org ([174.143.236.118]:44150 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751756Ab3J1Vv1 (ORCPT ); Mon, 28 Oct 2013 17:51:27 -0400 Date: Mon, 28 Oct 2013 17:51:26 -0400 From: "J. Bruce Fields" To: Anna Schumaker Cc: linux-nfs@vger.kernel.org Subject: Re: [PATCH 4/4] NFSD: Implement SEEK Message-ID: <20131028215126.GP31322@fieldses.org> References: <1382972247-1108-1-git-send-email-bjschuma@netapp.com> <1382972247-1108-5-git-send-email-bjschuma@netapp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1382972247-1108-5-git-send-email-bjschuma@netapp.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: On Mon, Oct 28, 2013 at 10:57:26AM -0400, Anna Schumaker wrote: > This patch adds in the SEEK operation used by clients doing an llseek on > a file to find either hole or data sections in a file. I'm faking the > "allocated" status right now, since I haven't quite figured out how to > tell if a range is allocated on disk yet. > > This patch is missing correctly determining the "allocated" status of > the HOLE / DATA range. I expect I'll need to learn all about how fiemap > works before properly setting these values. > > Signed-off-by: Anna Schumaker > --- > fs/nfsd/nfs4proc.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ > fs/nfsd/nfs4xdr.c | 40 ++++++++++++++++++++++++++++++++++++++-- > fs/nfsd/xdr4.h | 15 +++++++++++++++ > include/linux/nfs4.h | 2 +- > 4 files changed, 98 insertions(+), 3 deletions(-) > > diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c > index 3210c6f..bc45ed2 100644 > --- a/fs/nfsd/nfs4proc.c > +++ b/fs/nfsd/nfs4proc.c > @@ -1064,6 +1064,45 @@ nfsd4_write_plus(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, > return nfserr_union_notsupp; > } > > +static __be32 > +nfsd4_seek(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, > + struct nfsd4_seek *seek) > +{ > + struct file *file; > + loff_t pos, end_pos; > + __be32 status; > + > + status = nfs4_preprocess_stateid_op(SVC_NET(rqstp), cstate, > + &seek->seek_stateid, > + RD_STATE | WR_STATE, &file); Note nfs4_preprocess_stateid_op requires the caller to hold the state lock. Andyou want to either hold it till you're done using "file" or take a reference on file before dropping it. --b. > + if (status != nfs_ok) > + return status; > + > + if (seek->seek_whence == NFS4_CONTENT_DATA) { > + pos = vfs_llseek(file, seek->seek_offset, SEEK_DATA); > + end_pos = vfs_llseek(file, pos, SEEK_HOLE); > + seek->seek_allocated = true; > + } else { > + pos = vfs_llseek(file, seek->seek_offset, SEEK_HOLE); > + end_pos = vfs_llseek(file, pos, SEEK_DATA); > + seek->seek_allocated = false; > + } > + > + if (pos < 0) > + return nfserrno(pos); > + else if (end_pos == -ENXIO) { > + seek->seek_length = 0; > + seek->seek_eof = true; > + } else if (end_pos < 0) > + return nfserrno(end_pos); > + else > + seek->seek_length = end_pos - pos; > + > + seek->seek_offset = pos; > + > + return nfs_ok; > +} > + > /* 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 > @@ -1885,6 +1924,11 @@ static struct nfsd4_operation nfsd4_ops[] = { > .op_rsize_bop = (nfsd4op_rsize)nfsd4_write_rsize, > .op_get_currentstateid = (stateid_getter)nfsd4_get_writestateid, > }, > + > + [OP_SEEK] = { > + .op_func = (nfsd4op_func)nfsd4_seek, > + .op_name = "OP_SEEK", > + }, > }; > > #ifdef NFSD_DEBUG > diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c > index 1e4e9af..8434740 100644 > --- a/fs/nfsd/nfs4xdr.c > +++ b/fs/nfsd/nfs4xdr.c > @@ -1511,6 +1511,22 @@ nfsd4_decode_write_plus(struct nfsd4_compoundargs *argp, > } > > 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); > + READ64(seek->seek_offset); > + READ32(seek->seek_whence); > + > + DECODE_TAIL; > +} > + > +static __be32 > nfsd4_decode_noop(struct nfsd4_compoundargs *argp, void *p) > { > return nfs_ok; > @@ -1693,7 +1709,7 @@ static nfsd4_dec nfsd42_dec_ops[] = { > [OP_OFFLOAD_STATUS] = (nfsd4_dec)nfsd4_decode_notsupp, > [OP_WRITE_PLUS] = (nfsd4_dec)nfsd4_decode_write_plus, > [OP_READ_PLUS] = (nfsd4_dec)nfsd4_decode_notsupp, > - [OP_SEEK] = (nfsd4_dec)nfsd4_decode_notsupp, > + [OP_SEEK] = (nfsd4_dec)nfsd4_decode_seek, > [OP_IO_ADVISE] = (nfsd4_dec)nfsd4_decode_notsupp, > }; > > @@ -3650,6 +3666,26 @@ nfsd4_encode_write_plus(struct nfsd4_compoundres *resp, __be32 nfserr, > } > > static __be32 > +nfsd4_encode_seek(struct nfsd4_compoundres *resp, __be32 nfserr, > + struct nfsd4_seek *seek) > +{ > + __be32 *p; > + > + if (nfserr) > + return nfserr; > + > + RESERVE_SPACE(28); > + WRITE32(seek->seek_eof); > + WRITE32(seek->seek_whence); > + WRITE64(seek->seek_offset); > + WRITE64(seek->seek_length); > + WRITE32(seek->seek_allocated); > + ADJUST_ARGS(); > + > + return nfserr; > +} > + > +static __be32 > nfsd4_encode_noop(struct nfsd4_compoundres *resp, __be32 nfserr, void *p) > { > return nfserr; > @@ -3730,7 +3766,7 @@ static nfsd4_enc nfsd4_enc_ops[] = { > [OP_OFFLOAD_STATUS] = (nfsd4_enc)nfsd4_encode_noop, > [OP_WRITE_PLUS] = (nfsd4_enc)nfsd4_encode_write_plus, > [OP_READ_PLUS] = (nfsd4_enc)nfsd4_encode_noop, > - [OP_SEEK] = (nfsd4_enc)nfsd4_encode_noop, > + [OP_SEEK] = (nfsd4_enc)nfsd4_encode_seek, > [OP_IO_ADVISE] = (nfsd4_enc)nfsd4_encode_noop, > }; > > diff --git a/fs/nfsd/xdr4.h b/fs/nfsd/xdr4.h > index aaef9ab..ae9debc 100644 > --- a/fs/nfsd/xdr4.h > +++ b/fs/nfsd/xdr4.h > @@ -451,6 +451,20 @@ struct nfsd4_write_plus { > struct nfsd42_write_res wp_res; > }; > > +struct nfsd4_seek { > + /* request */ > + stateid_t seek_stateid; > + > + /* Shared between request and response */ > + u64 seek_offset; > + u32 seek_whence; > + > + /* response */ > + u32 seek_eof; > + u64 seek_length; > + u32 seek_allocated; > +}; > + > struct nfsd4_op { > int opnum; > __be32 status; > @@ -499,6 +513,7 @@ struct nfsd4_op { > > /* NFSv4.2 */ > struct nfsd4_write_plus write_plus; > + struct nfsd4_seek seek; > } u; > struct nfs4_replay * replay; > }; > diff --git a/include/linux/nfs4.h b/include/linux/nfs4.h > index 55ed991..81d6b09 100644 > --- a/include/linux/nfs4.h > +++ b/include/linux/nfs4.h > @@ -128,7 +128,7 @@ enum nfs_opnum4 { > Needs to be updated if more operations are defined in future.*/ > > #define FIRST_NFS4_OP OP_ACCESS > -#define LAST_NFS4_OP OP_WRITE_PLUS > +#define LAST_NFS4_OP OP_SEEK > > enum nfsstat4 { > NFS4_OK = 0, > -- > 1.8.4.1 >