Return-Path: linux-nfs-owner@vger.kernel.org Received: from mx12.netapp.com ([216.240.18.77]:6617 "EHLO mx12.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754896Ab3J2MxI (ORCPT ); Tue, 29 Oct 2013 08:53:08 -0400 Message-ID: <526FAFB2.8040300@netapp.com> Date: Tue, 29 Oct 2013 08:53:06 -0400 From: Anna Schumaker MIME-Version: 1.0 To: "J. Bruce Fields" CC: Subject: Re: [PATCH 4/4] NFSD: Implement SEEK References: <1382972247-1108-1-git-send-email-bjschuma@netapp.com> <1382972247-1108-5-git-send-email-bjschuma@netapp.com> <20131028215126.GP31322@fieldses.org> In-Reply-To: <20131028215126.GP31322@fieldses.org> Content-Type: text/plain; charset="UTF-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: On Mon 28 Oct 2013 05:51:26 PM EDT, J. Bruce Fields wrote: > 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. That's useful to know. I'll fix it up here, and anywhere else I call nfs4_preprocess_stateid_op()! > > --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 >>