NFS: Implement SEEK

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 <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This commit is contained in:
Anna Schumaker 2014-09-26 13:58:48 -04:00 committed by Trond Myklebust
parent 4a3a0ebad1
commit 1c6dcbe5ce
12 changed files with 244 additions and 2 deletions

View file

@ -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/

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@ -716,6 +716,7 @@ 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)
{
@ -728,6 +729,7 @@ 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

14
fs/nfs/nfs42.h Normal file
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@ -0,0 +1,14 @@
/*
* Copyright (c) 2014 Anna Schumaker <Anna.Schumaker@Netapp.com>
*/
#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 */

69
fs/nfs/nfs42proc.c Normal file
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@ -0,0 +1,69 @@
/*
* Copyright (c) 2014 Anna Schumaker <Anna.Schumaker@Netapp.com>
*/
#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);
}

98
fs/nfs/nfs42xdr.c Normal file
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@ -0,0 +1,98 @@
/*
* Copyright (c) 2014 Anna Schumaker <Anna.Schumaker@Netapp.com>
*/
#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 */

View file

@ -227,6 +227,9 @@ 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);

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@ -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,

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@ -875,7 +875,6 @@ 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,
@ -8429,7 +8428,8 @@ static const struct nfs4_minor_version_ops nfs_v4_1_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,

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@ -7427,6 +7427,10 @@ 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, \
@ -7495,6 +7499,9 @@ 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 = {

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@ -487,6 +487,9 @@ enum {
NFSPROC4_CLNT_GETDEVICELIST,
NFSPROC4_CLNT_BIND_CONN_TO_SESSION,
NFSPROC4_CLNT_DESTROY_CLIENTID,
/* nfs42 */
NFSPROC4_CLNT_SEEK,
};
/* nfs41 types */

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@ -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

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@ -1239,6 +1239,25 @@ 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)