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() when other flags are set or in the NFS < 4.2 case.
Signed-off-by: Anna Schumaker <bjschuma@xxxxxxxxxx>
---
fs/nfs/nfs4_fs.h | 1 +
fs/nfs/nfs4file.c | 38 +++++++++++++++++++++
fs/nfs/nfs4proc.c | 29 ++++++++++++++++
fs/nfs/nfs4xdr.c | 91 +++++++++++++++++++++++++++++++++++++++++++++++++
include/linux/nfs4.h | 1 +
include/linux/nfs_xdr.h | 20 +++++++++++
6 files changed, 180 insertions(+)
diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
index f52fc5f..badc1fa 100644
--- a/fs/nfs/nfs4_fs.h
+++ b/fs/nfs/nfs4_fs.h
@@ -355,6 +355,7 @@ nfs4_state_protect_write(struct nfs_client *clp, struct rpc_clnt **clntp,
#ifdef CONFIG_NFS_V4_2
int nfs42_proc_fallocate(struct nfs_server *, struct nfs42_write_plus_args *,
struct nfs42_write_res *, struct rpc_cred *);
+loff_t nfs42_proc_llseek(struct inode *, nfs4_stateid *, loff_t, int);
#endif /* CONFIG_NFS_V4_2 */
extern const struct nfs4_minor_version_ops *nfs_v4_minor_ops[];
diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c
index caf0658..b88ba0c 100644
--- a/fs/nfs/nfs4file.c
+++ b/fs/nfs/nfs4file.c
@@ -218,10 +218,48 @@ static long nfs42_fallocate(struct file *file, int mode, loff_t offset, loff_t l
err = nfs_wait_for_offload(&res);
return err;
}
+
+static loff_t nfs42_file_llseek(struct file *filep, loff_t offset, int whence)
+{
+ nfs4_stateid stateid;
+ struct nfs_open_context *ctx;
+ struct inode *inode = file_inode(filep);
+ loff_t pos;
+
+ pos = nfs42_select_stateid(filep, &stateid, FMODE_READ | FMODE_WRITE, &ctx);
+ if (pos < 0)
+ return pos;
+
+ nfs_wb_all(inode);
+ pos = nfs42_proc_llseek(inode, &stateid, offset, whence);
+ if (pos < 0)
+ return pos;
+ return vfs_setpos(filep, pos, inode->i_sb->s_maxbytes);
+}
+
+static loff_t nfs4_file_llseek(struct file *filep, loff_t offset, int whence)
+{
+ struct nfs_server *server = NFS_SERVER(file_inode(filep));
+
+ if (server->nfs_client->cl_minorversion < 2)
+ return nfs_file_llseek(filep, offset, whence);
+
+ switch (whence) {
+ case SEEK_HOLE:
+ case SEEK_DATA:
+ return nfs42_file_llseek(filep, offset, whence);
+ 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 = do_sync_read,
.write = do_sync_write,
.aio_read = nfs_file_read,
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 003bacb..79f1295 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -7865,6 +7865,35 @@ int nfs42_proc_fallocate(struct nfs_server *server,
return err;
}
+
+loff_t nfs42_proc_llseek(struct inode *inode, nfs4_stateid *stateid,
+ loff_t offset, int whence)
+{
+ struct nfs42_seek_args args = {
+ .sa_fh = NFS_FH(inode),
+ .sa_stateid = stateid,
+ .sa_offset = offset,
+ };
+ 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 (whence == SEEK_HOLE)
+ args.sa_what = NFS4_CONTENT_HOLE;
+ else
+ args.sa_what = NFS4_CONTENT_DATA;
+
+ status = nfs4_call_sync(server->client, server, &msg,
+ &args.seq_args, &res.seq_res, 0);
+ if (status)
+ return status;
+ return res.sr_offset;
+}
#endif /* CONFIG_NFS_V4_2 */
static bool nfs4_match_stateid(const nfs4_stateid *s1,
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 28e2fad..f7ced39 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -435,6 +435,10 @@ static int nfs4_stat_to_errno(int);
2 /* bytes written */ + \
1 /* committed */ + \
XDR_QUADLEN(NFS4_VERIFIER_SIZE))
+#define encode_seek_maxsz (op_encode_hdr_maxsz + \
+ XDR_QUADLEN(NFS4_STATEID_SIZE) + \
+ 2 + 1)
+#define decode_seek_maxsz (op_decode_hdr_maxsz + 1 + 1 + 5)
#endif /* CONFIG_NFS_V4_2 */
#define NFS4_enc_compound_sz (1024) /* XXX: large enough? */
@@ -903,6 +907,12 @@ EXPORT_SYMBOL_GPL(nfs41_maxgetdevinfo_overhead);
#define NFS4_dec_write_plus_sz (compound_decode_hdr_maxsz + \
decode_putfh_maxsz + \
decode_write_plus_maxsz)
+#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)
#endif /* CONFIG_NFS_V4_2 */
static const umode_t nfs_type2fmt[] = {
@@ -2104,6 +2114,16 @@ static void encode_write_plus(struct xdr_stream *xdr,
encode_uint32(xdr, 1);
encode_write_plus_hole(xdr, args);
}
+
+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);
+}
#endif /* CONFIG_NFS_V4_2 */
/*
@@ -3071,6 +3091,25 @@ static void nfs4_xdr_enc_write_plus(struct rpc_rqst *req,
encode_nops(&hdr);
return;
}
+
+/*
+ * 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);
+ return;
+}
#endif /* CONFIG_NFS_V4_2 */
static void print_overflow_msg(const char *func, const struct xdr_stream *xdr)
@@ -6081,6 +6120,33 @@ static int decode_writeplus(struct xdr_stream *xdr, struct nfs42_write_res *res)
return decode_write_response(xdr, res);
}
+
+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, 28);
+ if (unlikely(!p))
+ goto out_overflow;
+
+ res->sr_eof = be32_to_cpup(p++);
+ res->sr_whence = be32_to_cpup(p++);
+ p = xdr_decode_hyper(p, &res->sr_offset);
+ p = xdr_decode_hyper(p, &res->sr_length);
+ res->sr_allocated = be32_to_cpup(p);
+ return 0;
+
+out_overflow:
+ print_overflow_msg(__func__, xdr);
+ return -EIO;
+
+ return 0;
+}
#endif /* CONFIG_NFS_V4_2 */
/*
@@ -7320,6 +7386,30 @@ static int nfs4_xdr_dec_write_plus(struct rpc_rqst *rqstp,
out:
return status;
}
+
+/*
+ * 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 /* CONFIG_NFS_V4_2 */
/**
@@ -7533,6 +7623,7 @@ struct rpc_procinfo nfs4_procedures[] = {
#endif /* CONFIG_NFS_V4_1 */
#if defined(CONFIG_NFS_V4_2)
PROC(WRITE_PLUS, enc_write_plus, dec_write_plus),
+ PROC(SEEK, enc_seek, dec_seek),
#endif /* CONFIG_NFS_V4_2 */
};
diff --git a/include/linux/nfs4.h b/include/linux/nfs4.h
index 237016a..0d9033a 100644
--- a/include/linux/nfs4.h
+++ b/include/linux/nfs4.h
@@ -492,6 +492,7 @@ enum {
/* nfs42 */
NFSPROC4_CLNT_WRITE_PLUS,
+ NFSPROC4_CLNT_SEEK,
};
/* nfs41 types */
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index d8cbe5a..a46f803 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -1236,6 +1236,26 @@ struct nfs42_write_plus_args {
u32 wp_allocated;
};
+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;
+ u32 sr_whence;
+ u64 sr_offset;
+ u64 sr_length;
+ u32 sr_allocated;
+};
+
struct nfs42_write_res
{
struct nfs4_sequence_res seq_res;
--
1.8.4.1
--
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