2014-09-26 17:58:51

by Anna Schumaker

[permalink] [raw]
Subject: [PATCH v3] NFS: Add v4.2 SEEK support

This patch adds support for the NFS v4.2 operation SEEK. I add this
operation to new NFS v4.2 XDR and proc files to help ease the maintenance
burden on new operations.

Changes in v3:
- Rename nfs42xdr.h -> nfs42xdr.c
- Use nfs_v4_2_minor_ops to set up initial capabilities
- Do more work in nfs42proc.c (check capabilities, find correct stateids ...)

This patch and the corresponding server changes are available in the [seek]
branch of:

git://git.linux-nfs.org/projects/anna/linux-nfs.git

Questions? Comments? Thoughts?

Anna


Anna Schumaker (1):
NFS: Implement SEEK

fs/nfs/Makefile | 1 +
fs/nfs/inode.c | 2 +
fs/nfs/nfs42.h | 14 +++++++
fs/nfs/nfs42proc.c | 69 +++++++++++++++++++++++++++++++++
fs/nfs/nfs42xdr.c | 98 +++++++++++++++++++++++++++++++++++++++++++++++
fs/nfs/nfs4_fs.h | 3 ++
fs/nfs/nfs4file.c | 25 ++++++++++++
fs/nfs/nfs4proc.c | 4 +-
fs/nfs/nfs4xdr.c | 7 ++++
include/linux/nfs4.h | 3 ++
include/linux/nfs_fs_sb.h | 1 +
include/linux/nfs_xdr.h | 19 +++++++++
12 files changed, 244 insertions(+), 2 deletions(-)
create mode 100644 fs/nfs/nfs42.h
create mode 100644 fs/nfs/nfs42proc.c
create mode 100644 fs/nfs/nfs42xdr.c

--
2.1.0



2014-09-26 17:58:52

by Anna Schumaker

[permalink] [raw]
Subject: [PATCH v3] NFS: Implement SEEK

From: Anna Schumaker <[email protected]>

The SEEK operation is used when an application makes an lseek call with
either the SEEK_HOLE or SEEK_DATA flags set. I fall back on
nfs_file_llseek() if the server does not have SEEK support.

Signed-off-by: Anna Schumaker <[email protected]>
---
fs/nfs/Makefile | 1 +
fs/nfs/inode.c | 2 +
fs/nfs/nfs42.h | 14 +++++++
fs/nfs/nfs42proc.c | 69 +++++++++++++++++++++++++++++++++
fs/nfs/nfs42xdr.c | 98 +++++++++++++++++++++++++++++++++++++++++++++++
fs/nfs/nfs4_fs.h | 3 ++
fs/nfs/nfs4file.c | 25 ++++++++++++
fs/nfs/nfs4proc.c | 4 +-
fs/nfs/nfs4xdr.c | 7 ++++
include/linux/nfs4.h | 3 ++
include/linux/nfs_fs_sb.h | 1 +
include/linux/nfs_xdr.h | 19 +++++++++
12 files changed, 244 insertions(+), 2 deletions(-)
create mode 100644 fs/nfs/nfs42.h
create mode 100644 fs/nfs/nfs42proc.c
create mode 100644 fs/nfs/nfs42xdr.c

diff --git a/fs/nfs/Makefile b/fs/nfs/Makefile
index 4782e08..04cb830 100644
--- a/fs/nfs/Makefile
+++ b/fs/nfs/Makefile
@@ -28,6 +28,7 @@ nfsv4-y := nfs4proc.o nfs4xdr.o nfs4state.o nfs4renewd.o nfs4super.o nfs4file.o
nfsv4-$(CONFIG_NFS_USE_LEGACY_DNS) += cache_lib.o
nfsv4-$(CONFIG_SYSCTL) += nfs4sysctl.o
nfsv4-$(CONFIG_NFS_V4_1) += pnfs.o pnfs_dev.o
+nfsv4-$(CONFIG_NFS_V4_2) += nfs42proc.o

obj-$(CONFIG_PNFS_FILE_LAYOUT) += filelayout/
obj-$(CONFIG_PNFS_OBJLAYOUT) += objlayout/
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 141c9f4..6388a59 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -718,6 +718,7 @@ struct nfs_lock_context *nfs_get_lock_context(struct nfs_open_context *ctx)
kfree(new);
return res;
}
+EXPORT_SYMBOL_GPL(nfs_get_lock_context);

void nfs_put_lock_context(struct nfs_lock_context *l_ctx)
{
@@ -730,6 +731,7 @@ void nfs_put_lock_context(struct nfs_lock_context *l_ctx)
spin_unlock(&inode->i_lock);
kfree(l_ctx);
}
+EXPORT_SYMBOL_GPL(nfs_put_lock_context);

/**
* nfs_close_context - Common close_context() routine NFSv2/v3
diff --git a/fs/nfs/nfs42.h b/fs/nfs/nfs42.h
new file mode 100644
index 0000000..d10333a
--- /dev/null
+++ b/fs/nfs/nfs42.h
@@ -0,0 +1,14 @@
+/*
+ * Copyright (c) 2014 Anna Schumaker <[email protected]>
+ */
+
+#ifndef __LINUX_FS_NFS_NFS4_2_H
+#define __LINUX_FS_NFS_NFS4_2_H
+
+/* nfs4.2proc.c */
+loff_t nfs42_proc_llseek(struct file *, loff_t, int);
+
+/* nfs4.2xdr.h */
+extern struct rpc_procinfo nfs4_2_procedures[];
+
+#endif /* __LINUX_FS_NFS_NFS4_2_H */
diff --git a/fs/nfs/nfs42proc.c b/fs/nfs/nfs42proc.c
new file mode 100644
index 0000000..0886f1d
--- /dev/null
+++ b/fs/nfs/nfs42proc.c
@@ -0,0 +1,69 @@
+/*
+ * Copyright (c) 2014 Anna Schumaker <[email protected]>
+ */
+#include <linux/fs.h>
+#include <linux/sunrpc/sched.h>
+#include <linux/nfs.h>
+#include <linux/nfs3.h>
+#include <linux/nfs4.h>
+#include <linux/nfs_xdr.h>
+#include <linux/nfs_fs.h>
+#include "nfs4_fs.h"
+#include "nfs42.h"
+
+static int nfs42_set_rw_stateid(nfs4_stateid *dst, struct file *file,
+ fmode_t fmode)
+{
+ struct nfs_open_context *open;
+ struct nfs_lock_context *lock;
+ int ret;
+
+ open = get_nfs_open_context(nfs_file_open_context(file));
+ lock = nfs_get_lock_context(open);
+ if (IS_ERR(lock)) {
+ put_nfs_open_context(open);
+ return PTR_ERR(lock);
+ }
+
+ ret = nfs4_set_rw_stateid(dst, open, lock, fmode);
+
+ nfs_put_lock_context(lock);
+ put_nfs_open_context(open);
+ return ret;
+}
+
+loff_t nfs42_proc_llseek(struct file *filep, loff_t offset, int whence)
+{
+ struct inode *inode = file_inode(filep);
+ struct nfs42_seek_args args = {
+ .sa_fh = NFS_FH(inode),
+ .sa_offset = offset,
+ .sa_what = (whence == SEEK_HOLE) ?
+ NFS4_CONTENT_HOLE : NFS4_CONTENT_DATA,
+ };
+ struct nfs42_seek_res res;
+ struct rpc_message msg = {
+ .rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_SEEK],
+ .rpc_argp = &args,
+ .rpc_resp = &res,
+ };
+ struct nfs_server *server = NFS_SERVER(inode);
+ int status;
+
+ if (!(server->caps & NFS_CAP_SEEK))
+ return -ENOTSUPP;
+
+ status = nfs42_set_rw_stateid(&args.sa_stateid, filep, FMODE_READ);
+ if (status)
+ return status;
+
+ nfs_wb_all(inode);
+ status = nfs4_call_sync(server->client, server, &msg,
+ &args.seq_args, &res.seq_res, 0);
+ if (status == -ENOTSUPP)
+ server->caps &= ~NFS_CAP_SEEK;
+ if (status)
+ return status;
+
+ return vfs_setpos(filep, res.sr_offset, inode->i_sb->s_maxbytes);
+}
diff --git a/fs/nfs/nfs42xdr.c b/fs/nfs/nfs42xdr.c
new file mode 100644
index 0000000..c90469b
--- /dev/null
+++ b/fs/nfs/nfs42xdr.c
@@ -0,0 +1,98 @@
+/*
+ * Copyright (c) 2014 Anna Schumaker <[email protected]>
+ */
+#ifndef __LINUX_FS_NFS_NFS4_2XDR_H
+#define __LINUX_FS_NFS_NFS4_2XDR_H
+
+#define encode_seek_maxsz (op_encode_hdr_maxsz + \
+ encode_stateid_maxsz + \
+ 2 /* offset */ + \
+ 1 /* whence */)
+#define decode_seek_maxsz (op_decode_hdr_maxsz + \
+ 1 /* eof */ + \
+ 1 /* whence */ + \
+ 2 /* offset */ + \
+ 2 /* length */)
+
+#define NFS4_enc_seek_sz (compound_encode_hdr_maxsz + \
+ encode_putfh_maxsz + \
+ encode_seek_maxsz)
+#define NFS4_dec_seek_sz (compound_decode_hdr_maxsz + \
+ decode_putfh_maxsz + \
+ decode_seek_maxsz)
+
+
+static void encode_seek(struct xdr_stream *xdr,
+ struct nfs42_seek_args *args,
+ struct compound_hdr *hdr)
+{
+ encode_op_hdr(xdr, OP_SEEK, decode_seek_maxsz, hdr);
+ encode_nfs4_stateid(xdr, &args->sa_stateid);
+ encode_uint64(xdr, args->sa_offset);
+ encode_uint32(xdr, args->sa_what);
+}
+
+/*
+ * Encode SEEK request
+ */
+static void nfs4_xdr_enc_seek(struct rpc_rqst *req,
+ struct xdr_stream *xdr,
+ struct nfs42_seek_args *args)
+{
+ struct compound_hdr hdr = {
+ .minorversion = nfs4_xdr_minorversion(&args->seq_args),
+ };
+
+ encode_compound_hdr(xdr, req, &hdr);
+ encode_sequence(xdr, &args->seq_args, &hdr);
+ encode_putfh(xdr, args->sa_fh, &hdr);
+ encode_seek(xdr, args, &hdr);
+ encode_nops(&hdr);
+}
+
+static int decode_seek(struct xdr_stream *xdr, struct nfs42_seek_res *res)
+{
+ int status;
+ __be32 *p;
+
+ status = decode_op_hdr(xdr, OP_SEEK);
+ if (status)
+ return status;
+
+ p = xdr_inline_decode(xdr, 4 + 8);
+ if (unlikely(!p))
+ goto out_overflow;
+
+ res->sr_eof = be32_to_cpup(p++);
+ p = xdr_decode_hyper(p, &res->sr_offset);
+ return 0;
+
+out_overflow:
+ print_overflow_msg(__func__, xdr);
+ return -EIO;
+}
+
+/*
+ * Decode SEEK request
+ */
+static int nfs4_xdr_dec_seek(struct rpc_rqst *rqstp,
+ struct xdr_stream *xdr,
+ struct nfs42_seek_res *res)
+{
+ struct compound_hdr hdr;
+ int status;
+
+ status = decode_compound_hdr(xdr, &hdr);
+ if (status)
+ goto out;
+ status = decode_sequence(xdr, &res->seq_res, rqstp);
+ if (status)
+ goto out;
+ status = decode_putfh(xdr);
+ if (status)
+ goto out;
+ status = decode_seek(xdr, res);
+out:
+ return status;
+}
+#endif /* __LINUX_FS_NFS_NFS4_2XDR_H */
diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
index a8b855a..be6cac3 100644
--- a/fs/nfs/nfs4_fs.h
+++ b/fs/nfs/nfs4_fs.h
@@ -226,6 +226,9 @@ int nfs4_replace_transport(struct nfs_server *server,
const struct nfs4_fs_locations *locations);

/* nfs4proc.c */
+extern int nfs4_call_sync(struct rpc_clnt *, struct nfs_server *,
+ struct rpc_message *, struct nfs4_sequence_args *,
+ struct nfs4_sequence_res *, int);
extern int nfs4_proc_setclientid(struct nfs_client *, u32, unsigned short, struct rpc_cred *, struct nfs4_setclientid_res *);
extern int nfs4_proc_setclientid_confirm(struct nfs_client *, struct nfs4_setclientid_res *arg, struct rpc_cred *);
extern int nfs4_proc_get_rootfh(struct nfs_server *, struct nfs_fh *, struct nfs_fsinfo *, bool);
diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c
index a816f06..4dffa3a 100644
--- a/fs/nfs/nfs4file.c
+++ b/fs/nfs/nfs4file.c
@@ -8,6 +8,10 @@
#include "fscache.h"
#include "pnfs.h"

+#ifdef CONFIG_NFS_V4_2
+#include "nfs42.h"
+#endif
+
#define NFSDBG_FACILITY NFSDBG_FILE

static int
@@ -115,8 +119,29 @@ nfs4_file_fsync(struct file *file, loff_t start, loff_t end, int datasync)
return ret;
}

+#ifdef CONFIG_NFS_V4_2
+static loff_t nfs4_file_llseek(struct file *filep, loff_t offset, int whence)
+{
+ loff_t ret;
+
+ switch (whence) {
+ case SEEK_HOLE:
+ case SEEK_DATA:
+ ret = nfs42_proc_llseek(filep, offset, whence);
+ if (ret != -ENOTSUPP)
+ return ret;
+ default:
+ return nfs_file_llseek(filep, offset, whence);
+ }
+}
+#endif /* CONFIG_NFS_V4_2 */
+
const struct file_operations nfs4_file_operations = {
+#ifdef CONFIG_NFS_V4_2
+ .llseek = nfs4_file_llseek,
+#else
.llseek = nfs_file_llseek,
+#endif
.read = new_sync_read,
.write = new_sync_write,
.read_iter = nfs_file_read,
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 549d3b0..ba5eda3 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -885,7 +885,6 @@ static int nfs4_call_sync_sequence(struct rpc_clnt *clnt,
return ret;
}

-static
int nfs4_call_sync(struct rpc_clnt *clnt,
struct nfs_server *server,
struct rpc_message *msg,
@@ -8431,7 +8430,8 @@ static const struct nfs4_minor_version_ops nfs_v4_2_minor_ops = {
| NFS_CAP_CHANGE_ATTR
| NFS_CAP_POSIX_LOCK
| NFS_CAP_STATEID_NFSV41
- | NFS_CAP_ATOMIC_OPEN_V1,
+ | NFS_CAP_ATOMIC_OPEN_V1
+ | NFS_CAP_SEEK,
.init_client = nfs41_init_client,
.shutdown_client = nfs41_shutdown_client,
.match_stateid = nfs41_match_stateid,
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 005d03c..206c08a 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -7321,6 +7321,10 @@ nfs4_stat_to_errno(int stat)
return -stat;
}

+#ifdef CONFIG_NFS_V4_2
+#include "nfs42xdr.c"
+#endif /* CONFIG_NFS_V4_2 */
+
#define PROC(proc, argtype, restype) \
[NFSPROC4_CLNT_##proc] = { \
.p_proc = NFSPROC4_COMPOUND, \
@@ -7388,6 +7392,9 @@ struct rpc_procinfo nfs4_procedures[] = {
enc_bind_conn_to_session, dec_bind_conn_to_session),
PROC(DESTROY_CLIENTID, enc_destroy_clientid, dec_destroy_clientid),
#endif /* CONFIG_NFS_V4_1 */
+#ifdef CONFIG_NFS_V4_2
+ PROC(SEEK, enc_seek, dec_seek),
+#endif /* CONFIG_NFS_V4_2 */
};

const struct rpc_version nfs_version4 = {
diff --git a/include/linux/nfs4.h b/include/linux/nfs4.h
index 026b0c0..356acc2 100644
--- a/include/linux/nfs4.h
+++ b/include/linux/nfs4.h
@@ -487,6 +487,9 @@ enum {
NFSPROC4_CLNT_GETDEVICELIST,
NFSPROC4_CLNT_BIND_CONN_TO_SESSION,
NFSPROC4_CLNT_DESTROY_CLIENTID,
+
+ /* nfs42 */
+ NFSPROC4_CLNT_SEEK,
};

/* nfs41 types */
diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index 922be2e..a32ba0d 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -230,5 +230,6 @@ struct nfs_server {
#define NFS_CAP_STATEID_NFSV41 (1U << 16)
#define NFS_CAP_ATOMIC_OPEN_V1 (1U << 17)
#define NFS_CAP_SECURITY_LABEL (1U << 18)
+#define NFS_CAP_SEEK (1U << 19)

#endif
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 6951c7d..983876f 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -1231,6 +1231,25 @@ struct pnfs_ds_commit_info {

#endif /* CONFIG_NFS_V4_1 */

+#ifdef CONFIG_NFS_V4_2
+struct nfs42_seek_args {
+ struct nfs4_sequence_args seq_args;
+
+ struct nfs_fh *sa_fh;
+ nfs4_stateid sa_stateid;
+ u64 sa_offset;
+ u32 sa_what;
+};
+
+struct nfs42_seek_res {
+ struct nfs4_sequence_res seq_res;
+ unsigned int status;
+
+ u32 sr_eof;
+ u64 sr_offset;
+};
+#endif
+
struct nfs_page;

#define NFS_PAGEVEC_SIZE (8U)
--
2.1.0


2014-10-23 07:36:08

by Christoph Hellwig

[permalink] [raw]
Subject: Re: [PATCH v3] NFS: Implement SEEK

On Wed, Oct 22, 2014 at 03:50:15PM -0400, Anna Schumaker wrote:
> > int nfs4_call_sync(struct rpc_clnt *clnt,
> > struct nfs_server *server,
> > struct rpc_message *msg,
> > @@ -8431,7 +8430,8 @@ static const struct nfs4_minor_version_ops nfs_v4_2_minor_ops = {
> > | NFS_CAP_CHANGE_ATTR
> > | NFS_CAP_POSIX_LOCK
> > | NFS_CAP_STATEID_NFSV41
> > - | NFS_CAP_ATOMIC_OPEN_V1,
> > + | NFS_CAP_ATOMIC_OPEN_V1
> > + | NFS_CAP_SEEK,
>
> This looks like it really does add the capability to nfs_v4_2_minor_ops, so I'm not sure how it ended up modifying nfs_v4_1_minor_ops instead. Anyway, I just posted a fix to set the flag in the right place.

Given that the caps were the same before this is something that patch
can easily do when applying patches with a fuzz.

2014-10-22 19:50:18

by Anna Schumaker

[permalink] [raw]
Subject: Re: [PATCH v3] NFS: Implement SEEK

On 09/26/14 13:58, Anna Schumaker wrote:
> From: Anna Schumaker <[email protected]>
>
> The SEEK operation is used when an application makes an lseek call with
> either the SEEK_HOLE or SEEK_DATA flags set. I fall back on
> nfs_file_llseek() if the server does not have SEEK support.
>
> Signed-off-by: Anna Schumaker <[email protected]>
> ---
> fs/nfs/Makefile | 1 +
> fs/nfs/inode.c | 2 +
> fs/nfs/nfs42.h | 14 +++++++
> fs/nfs/nfs42proc.c | 69 +++++++++++++++++++++++++++++++++
> fs/nfs/nfs42xdr.c | 98 +++++++++++++++++++++++++++++++++++++++++++++++
> fs/nfs/nfs4_fs.h | 3 ++
> fs/nfs/nfs4file.c | 25 ++++++++++++
> fs/nfs/nfs4proc.c | 4 +-
> fs/nfs/nfs4xdr.c | 7 ++++
> include/linux/nfs4.h | 3 ++
> include/linux/nfs_fs_sb.h | 1 +
> include/linux/nfs_xdr.h | 19 +++++++++
> 12 files changed, 244 insertions(+), 2 deletions(-)
> create mode 100644 fs/nfs/nfs42.h
> create mode 100644 fs/nfs/nfs42proc.c
> create mode 100644 fs/nfs/nfs42xdr.c
>
> diff --git a/fs/nfs/Makefile b/fs/nfs/Makefile
> index 4782e08..04cb830 100644
> --- a/fs/nfs/Makefile
> +++ b/fs/nfs/Makefile
> @@ -28,6 +28,7 @@ nfsv4-y := nfs4proc.o nfs4xdr.o nfs4state.o nfs4renewd.o nfs4super.o nfs4file.o
> nfsv4-$(CONFIG_NFS_USE_LEGACY_DNS) += cache_lib.o
> nfsv4-$(CONFIG_SYSCTL) += nfs4sysctl.o
> nfsv4-$(CONFIG_NFS_V4_1) += pnfs.o pnfs_dev.o
> +nfsv4-$(CONFIG_NFS_V4_2) += nfs42proc.o
>
> obj-$(CONFIG_PNFS_FILE_LAYOUT) += filelayout/
> obj-$(CONFIG_PNFS_OBJLAYOUT) += objlayout/
> diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
> index 141c9f4..6388a59 100644
> --- a/fs/nfs/inode.c
> +++ b/fs/nfs/inode.c
> @@ -718,6 +718,7 @@ struct nfs_lock_context *nfs_get_lock_context(struct nfs_open_context *ctx)
> kfree(new);
> return res;
> }
> +EXPORT_SYMBOL_GPL(nfs_get_lock_context);
>
> void nfs_put_lock_context(struct nfs_lock_context *l_ctx)
> {
> @@ -730,6 +731,7 @@ void nfs_put_lock_context(struct nfs_lock_context *l_ctx)
> spin_unlock(&inode->i_lock);
> kfree(l_ctx);
> }
> +EXPORT_SYMBOL_GPL(nfs_put_lock_context);
>
> /**
> * nfs_close_context - Common close_context() routine NFSv2/v3
> diff --git a/fs/nfs/nfs42.h b/fs/nfs/nfs42.h
> new file mode 100644
> index 0000000..d10333a
> --- /dev/null
> +++ b/fs/nfs/nfs42.h
> @@ -0,0 +1,14 @@
> +/*
> + * Copyright (c) 2014 Anna Schumaker <[email protected]>
> + */
> +
> +#ifndef __LINUX_FS_NFS_NFS4_2_H
> +#define __LINUX_FS_NFS_NFS4_2_H
> +
> +/* nfs4.2proc.c */
> +loff_t nfs42_proc_llseek(struct file *, loff_t, int);
> +
> +/* nfs4.2xdr.h */
> +extern struct rpc_procinfo nfs4_2_procedures[];
> +
> +#endif /* __LINUX_FS_NFS_NFS4_2_H */
> diff --git a/fs/nfs/nfs42proc.c b/fs/nfs/nfs42proc.c
> new file mode 100644
> index 0000000..0886f1d
> --- /dev/null
> +++ b/fs/nfs/nfs42proc.c
> @@ -0,0 +1,69 @@
> +/*
> + * Copyright (c) 2014 Anna Schumaker <[email protected]>
> + */
> +#include <linux/fs.h>
> +#include <linux/sunrpc/sched.h>
> +#include <linux/nfs.h>
> +#include <linux/nfs3.h>
> +#include <linux/nfs4.h>
> +#include <linux/nfs_xdr.h>
> +#include <linux/nfs_fs.h>
> +#include "nfs4_fs.h"
> +#include "nfs42.h"
> +
> +static int nfs42_set_rw_stateid(nfs4_stateid *dst, struct file *file,
> + fmode_t fmode)
> +{
> + struct nfs_open_context *open;
> + struct nfs_lock_context *lock;
> + int ret;
> +
> + open = get_nfs_open_context(nfs_file_open_context(file));
> + lock = nfs_get_lock_context(open);
> + if (IS_ERR(lock)) {
> + put_nfs_open_context(open);
> + return PTR_ERR(lock);
> + }
> +
> + ret = nfs4_set_rw_stateid(dst, open, lock, fmode);
> +
> + nfs_put_lock_context(lock);
> + put_nfs_open_context(open);
> + return ret;
> +}
> +
> +loff_t nfs42_proc_llseek(struct file *filep, loff_t offset, int whence)
> +{
> + struct inode *inode = file_inode(filep);
> + struct nfs42_seek_args args = {
> + .sa_fh = NFS_FH(inode),
> + .sa_offset = offset,
> + .sa_what = (whence == SEEK_HOLE) ?
> + NFS4_CONTENT_HOLE : NFS4_CONTENT_DATA,
> + };
> + struct nfs42_seek_res res;
> + struct rpc_message msg = {
> + .rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_SEEK],
> + .rpc_argp = &args,
> + .rpc_resp = &res,
> + };
> + struct nfs_server *server = NFS_SERVER(inode);
> + int status;
> +
> + if (!(server->caps & NFS_CAP_SEEK))
> + return -ENOTSUPP;
> +
> + status = nfs42_set_rw_stateid(&args.sa_stateid, filep, FMODE_READ);
> + if (status)
> + return status;
> +
> + nfs_wb_all(inode);
> + status = nfs4_call_sync(server->client, server, &msg,
> + &args.seq_args, &res.seq_res, 0);
> + if (status == -ENOTSUPP)
> + server->caps &= ~NFS_CAP_SEEK;
> + if (status)
> + return status;
> +
> + return vfs_setpos(filep, res.sr_offset, inode->i_sb->s_maxbytes);
> +}
> diff --git a/fs/nfs/nfs42xdr.c b/fs/nfs/nfs42xdr.c
> new file mode 100644
> index 0000000..c90469b
> --- /dev/null
> +++ b/fs/nfs/nfs42xdr.c
> @@ -0,0 +1,98 @@
> +/*
> + * Copyright (c) 2014 Anna Schumaker <[email protected]>
> + */
> +#ifndef __LINUX_FS_NFS_NFS4_2XDR_H
> +#define __LINUX_FS_NFS_NFS4_2XDR_H
> +
> +#define encode_seek_maxsz (op_encode_hdr_maxsz + \
> + encode_stateid_maxsz + \
> + 2 /* offset */ + \
> + 1 /* whence */)
> +#define decode_seek_maxsz (op_decode_hdr_maxsz + \
> + 1 /* eof */ + \
> + 1 /* whence */ + \
> + 2 /* offset */ + \
> + 2 /* length */)
> +
> +#define NFS4_enc_seek_sz (compound_encode_hdr_maxsz + \
> + encode_putfh_maxsz + \
> + encode_seek_maxsz)
> +#define NFS4_dec_seek_sz (compound_decode_hdr_maxsz + \
> + decode_putfh_maxsz + \
> + decode_seek_maxsz)
> +
> +
> +static void encode_seek(struct xdr_stream *xdr,
> + struct nfs42_seek_args *args,
> + struct compound_hdr *hdr)
> +{
> + encode_op_hdr(xdr, OP_SEEK, decode_seek_maxsz, hdr);
> + encode_nfs4_stateid(xdr, &args->sa_stateid);
> + encode_uint64(xdr, args->sa_offset);
> + encode_uint32(xdr, args->sa_what);
> +}
> +
> +/*
> + * Encode SEEK request
> + */
> +static void nfs4_xdr_enc_seek(struct rpc_rqst *req,
> + struct xdr_stream *xdr,
> + struct nfs42_seek_args *args)
> +{
> + struct compound_hdr hdr = {
> + .minorversion = nfs4_xdr_minorversion(&args->seq_args),
> + };
> +
> + encode_compound_hdr(xdr, req, &hdr);
> + encode_sequence(xdr, &args->seq_args, &hdr);
> + encode_putfh(xdr, args->sa_fh, &hdr);
> + encode_seek(xdr, args, &hdr);
> + encode_nops(&hdr);
> +}
> +
> +static int decode_seek(struct xdr_stream *xdr, struct nfs42_seek_res *res)
> +{
> + int status;
> + __be32 *p;
> +
> + status = decode_op_hdr(xdr, OP_SEEK);
> + if (status)
> + return status;
> +
> + p = xdr_inline_decode(xdr, 4 + 8);
> + if (unlikely(!p))
> + goto out_overflow;
> +
> + res->sr_eof = be32_to_cpup(p++);
> + p = xdr_decode_hyper(p, &res->sr_offset);
> + return 0;
> +
> +out_overflow:
> + print_overflow_msg(__func__, xdr);
> + return -EIO;
> +}
> +
> +/*
> + * Decode SEEK request
> + */
> +static int nfs4_xdr_dec_seek(struct rpc_rqst *rqstp,
> + struct xdr_stream *xdr,
> + struct nfs42_seek_res *res)
> +{
> + struct compound_hdr hdr;
> + int status;
> +
> + status = decode_compound_hdr(xdr, &hdr);
> + if (status)
> + goto out;
> + status = decode_sequence(xdr, &res->seq_res, rqstp);
> + if (status)
> + goto out;
> + status = decode_putfh(xdr);
> + if (status)
> + goto out;
> + status = decode_seek(xdr, res);
> +out:
> + return status;
> +}
> +#endif /* __LINUX_FS_NFS_NFS4_2XDR_H */
> diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
> index a8b855a..be6cac3 100644
> --- a/fs/nfs/nfs4_fs.h
> +++ b/fs/nfs/nfs4_fs.h
> @@ -226,6 +226,9 @@ int nfs4_replace_transport(struct nfs_server *server,
> const struct nfs4_fs_locations *locations);
>
> /* nfs4proc.c */
> +extern int nfs4_call_sync(struct rpc_clnt *, struct nfs_server *,
> + struct rpc_message *, struct nfs4_sequence_args *,
> + struct nfs4_sequence_res *, int);
> extern int nfs4_proc_setclientid(struct nfs_client *, u32, unsigned short, struct rpc_cred *, struct nfs4_setclientid_res *);
> extern int nfs4_proc_setclientid_confirm(struct nfs_client *, struct nfs4_setclientid_res *arg, struct rpc_cred *);
> extern int nfs4_proc_get_rootfh(struct nfs_server *, struct nfs_fh *, struct nfs_fsinfo *, bool);
> diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c
> index a816f06..4dffa3a 100644
> --- a/fs/nfs/nfs4file.c
> +++ b/fs/nfs/nfs4file.c
> @@ -8,6 +8,10 @@
> #include "fscache.h"
> #include "pnfs.h"
>
> +#ifdef CONFIG_NFS_V4_2
> +#include "nfs42.h"
> +#endif
> +
> #define NFSDBG_FACILITY NFSDBG_FILE
>
> static int
> @@ -115,8 +119,29 @@ nfs4_file_fsync(struct file *file, loff_t start, loff_t end, int datasync)
> return ret;
> }
>
> +#ifdef CONFIG_NFS_V4_2
> +static loff_t nfs4_file_llseek(struct file *filep, loff_t offset, int whence)
> +{
> + loff_t ret;
> +
> + switch (whence) {
> + case SEEK_HOLE:
> + case SEEK_DATA:
> + ret = nfs42_proc_llseek(filep, offset, whence);
> + if (ret != -ENOTSUPP)
> + return ret;
> + default:
> + return nfs_file_llseek(filep, offset, whence);
> + }
> +}
> +#endif /* CONFIG_NFS_V4_2 */
> +
> const struct file_operations nfs4_file_operations = {
> +#ifdef CONFIG_NFS_V4_2
> + .llseek = nfs4_file_llseek,
> +#else
> .llseek = nfs_file_llseek,
> +#endif
> .read = new_sync_read,
> .write = new_sync_write,
> .read_iter = nfs_file_read,
> diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
> index 549d3b0..ba5eda3 100644
> --- a/fs/nfs/nfs4proc.c
> +++ b/fs/nfs/nfs4proc.c
> @@ -885,7 +885,6 @@ static int nfs4_call_sync_sequence(struct rpc_clnt *clnt,
> return ret;
> }
>
> -static
> int nfs4_call_sync(struct rpc_clnt *clnt,
> struct nfs_server *server,
> struct rpc_message *msg,
> @@ -8431,7 +8430,8 @@ static const struct nfs4_minor_version_ops nfs_v4_2_minor_ops = {
> | NFS_CAP_CHANGE_ATTR
> | NFS_CAP_POSIX_LOCK
> | NFS_CAP_STATEID_NFSV41
> - | NFS_CAP_ATOMIC_OPEN_V1,
> + | NFS_CAP_ATOMIC_OPEN_V1
> + | NFS_CAP_SEEK,

This looks like it really does add the capability to nfs_v4_2_minor_ops, so I'm not sure how it ended up modifying nfs_v4_1_minor_ops instead. Anyway, I just posted a fix to set the flag in the right place.

Anna

> .init_client = nfs41_init_client,
> .shutdown_client = nfs41_shutdown_client,
> .match_stateid = nfs41_match_stateid,
> diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
> index 005d03c..206c08a 100644
> --- a/fs/nfs/nfs4xdr.c
> +++ b/fs/nfs/nfs4xdr.c
> @@ -7321,6 +7321,10 @@ nfs4_stat_to_errno(int stat)
> return -stat;
> }
>
> +#ifdef CONFIG_NFS_V4_2
> +#include "nfs42xdr.c"
> +#endif /* CONFIG_NFS_V4_2 */
> +
> #define PROC(proc, argtype, restype) \
> [NFSPROC4_CLNT_##proc] = { \
> .p_proc = NFSPROC4_COMPOUND, \
> @@ -7388,6 +7392,9 @@ struct rpc_procinfo nfs4_procedures[] = {
> enc_bind_conn_to_session, dec_bind_conn_to_session),
> PROC(DESTROY_CLIENTID, enc_destroy_clientid, dec_destroy_clientid),
> #endif /* CONFIG_NFS_V4_1 */
> +#ifdef CONFIG_NFS_V4_2
> + PROC(SEEK, enc_seek, dec_seek),
> +#endif /* CONFIG_NFS_V4_2 */
> };
>
> const struct rpc_version nfs_version4 = {
> diff --git a/include/linux/nfs4.h b/include/linux/nfs4.h
> index 026b0c0..356acc2 100644
> --- a/include/linux/nfs4.h
> +++ b/include/linux/nfs4.h
> @@ -487,6 +487,9 @@ enum {
> NFSPROC4_CLNT_GETDEVICELIST,
> NFSPROC4_CLNT_BIND_CONN_TO_SESSION,
> NFSPROC4_CLNT_DESTROY_CLIENTID,
> +
> + /* nfs42 */
> + NFSPROC4_CLNT_SEEK,
> };
>
> /* nfs41 types */
> diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
> index 922be2e..a32ba0d 100644
> --- a/include/linux/nfs_fs_sb.h
> +++ b/include/linux/nfs_fs_sb.h
> @@ -230,5 +230,6 @@ struct nfs_server {
> #define NFS_CAP_STATEID_NFSV41 (1U << 16)
> #define NFS_CAP_ATOMIC_OPEN_V1 (1U << 17)
> #define NFS_CAP_SECURITY_LABEL (1U << 18)
> +#define NFS_CAP_SEEK (1U << 19)
>
> #endif
> diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
> index 6951c7d..983876f 100644
> --- a/include/linux/nfs_xdr.h
> +++ b/include/linux/nfs_xdr.h
> @@ -1231,6 +1231,25 @@ struct pnfs_ds_commit_info {
>
> #endif /* CONFIG_NFS_V4_1 */
>
> +#ifdef CONFIG_NFS_V4_2
> +struct nfs42_seek_args {
> + struct nfs4_sequence_args seq_args;
> +
> + struct nfs_fh *sa_fh;
> + nfs4_stateid sa_stateid;
> + u64 sa_offset;
> + u32 sa_what;
> +};
> +
> +struct nfs42_seek_res {
> + struct nfs4_sequence_res seq_res;
> + unsigned int status;
> +
> + u32 sr_eof;
> + u64 sr_offset;
> +};
> +#endif
> +
> struct nfs_page;
>
> #define NFS_PAGEVEC_SIZE (8U)