4 files changed, 102 insertions, 2 deletions

diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 5e0dc528a0e8..cdeb3cfd6f32 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -1013,6 +1013,49 @@ nfsd4_write(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
         return status;
 }
 
+static __be32
+nfsd4_seek(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
+                struct nfsd4_seek *seek)
+{
+        int whence;
+        __be32 status;
+        struct file *file;
+
+        status = nfs4_preprocess_stateid_op(SVC_NET(rqstp), cstate,
+                                            &seek->seek_stateid,
+                                            RD_STATE, &file);
+        if (status) {
+                dprintk("NFSD: nfsd4_seek: couldn't process stateid!\n");
+                return status;
+        }
+
+        switch (seek->seek_whence) {
+        case NFS4_CONTENT_DATA:
+                whence = SEEK_DATA;
+                break;
+        case NFS4_CONTENT_HOLE:
+                whence = SEEK_HOLE;
+                break;
+        default:
+                status = nfserr_union_notsupp;
+                goto out;
+        }
+
+        /*
+         * Note:  This call does change file->f_pos, but nothing in NFSD
+         *        should ever file->f_pos.
+         */
+        seek->seek_pos = vfs_llseek(file, seek->seek_offset, whence);
+        if (seek->seek_pos < 0)
+                status = nfserrno(seek->seek_pos);
+        else if (seek->seek_pos >= i_size_read(file_inode(file)))
+                seek->seek_eof = true;
+
+out:
+        fput(file);
+        return status;
+}
+
 /* 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
@@ -1881,6 +1924,12 @@ static struct nfsd4_operation nfsd4_ops[] = {
                 .op_get_currentstateid = (stateid_getter)nfsd4_get_freestateid,
                 .op_rsize_bop = (nfsd4op_rsize)nfsd4_only_status_rsize,
         },
+
+        /* NFSv4.2 operations */
+        [OP_SEEK] = {
+                .op_func = (nfsd4op_func)nfsd4_seek,
+                .op_name = "OP_SEEK",
+        },
 };
 
 int nfsd4_max_reply(struct svc_rqst *rqstp, struct nfsd4_op *op)
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 0311baebd7d3..7ec646380005 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -1514,6 +1514,22 @@ static __be32 nfsd4_decode_reclaim_complete(struct nfsd4_compoundargs *argp, str
 }
 
 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(8 + 4);
+        p = xdr_decode_hyper(p, &seek->seek_offset);
+        seek->seek_whence = be32_to_cpup(p);
+
+        DECODE_TAIL;
+}
+
+static __be32
 nfsd4_decode_noop(struct nfsd4_compoundargs *argp, void *p)
 {
         return nfs_ok;
@@ -1598,7 +1614,7 @@ static nfsd4_dec nfsd4_dec_ops[] = {
         [OP_OFFLOAD_CANCEL]     = (nfsd4_dec)nfsd4_decode_notsupp,
         [OP_OFFLOAD_STATUS]     = (nfsd4_dec)nfsd4_decode_notsupp,
         [OP_READ_PLUS]          = (nfsd4_dec)nfsd4_decode_notsupp,
-        [OP_SEEK]               = (nfsd4_dec)nfsd4_decode_notsupp,
+        [OP_SEEK]               = (nfsd4_dec)nfsd4_decode_seek,
         [OP_WRITE_SAME]         = (nfsd4_dec)nfsd4_decode_notsupp,
 };
 
@@ -3766,6 +3782,22 @@ nfsd4_encode_test_stateid(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;
+
+        p = xdr_reserve_space(&resp->xdr, 4 + 8);
+        *p++ = cpu_to_be32(seek->seek_eof);
+        p = xdr_encode_hyper(p, seek->seek_pos);
+
+        return nfserr;
+}
+
+static __be32
 nfsd4_encode_noop(struct nfsd4_compoundres *resp, __be32 nfserr, void *p)
 {
         return nfserr;
@@ -3849,7 +3881,7 @@ static nfsd4_enc nfsd4_enc_ops[] = {
         [OP_OFFLOAD_CANCEL]     = (nfsd4_enc)nfsd4_encode_noop,
         [OP_OFFLOAD_STATUS]     = (nfsd4_enc)nfsd4_encode_noop,
         [OP_READ_PLUS]          = (nfsd4_enc)nfsd4_encode_noop,
-        [OP_SEEK]               = (nfsd4_enc)nfsd4_encode_noop,
+        [OP_SEEK]               = (nfsd4_enc)nfsd4_encode_seek,
         [OP_WRITE_SAME]         = (nfsd4_enc)nfsd4_encode_noop,
 };
 
diff --git a/fs/nfsd/xdr4.h b/fs/nfsd/xdr4.h
index 465e7799742a..5720e9457f33 100644
--- a/fs/nfsd/xdr4.h
+++ b/fs/nfsd/xdr4.h
@@ -428,6 +428,17 @@ struct nfsd4_reclaim_complete {
         u32 rca_one_fs;
 };
 
+struct nfsd4_seek {
+        /* request */
+        stateid_t       seek_stateid;
+        loff_t          seek_offset;
+        u32             seek_whence;
+
+        /* response */
+        u32             seek_eof;
+        loff_t          seek_pos;
+};
+
 struct nfsd4_op {
         int                                     opnum;
         __be32                                  status;
@@ -473,6 +484,9 @@ struct nfsd4_op {
                 struct nfsd4_reclaim_complete   reclaim_complete;
                 struct nfsd4_test_stateid       test_stateid;
                 struct nfsd4_free_stateid       free_stateid;
+
+                /* NFSv4.2 */
+                struct nfsd4_seek               seek;
         } u;
         struct nfs4_replay *                    replay;
 };
diff --git a/include/linux/nfs4.h b/include/linux/nfs4.h
index cf38224c4fa0..026b0c042c40 100644
--- a/include/linux/nfs4.h
+++ b/include/linux/nfs4.h
@@ -550,4 +550,9 @@ struct nfs4_deviceid {
         char data[NFS4_DEVICEID4_SIZE];
 };
 
+enum data_content4 {
+        NFS4_CONTENT_DATA               = 0,
+        NFS4_CONTENT_HOLE               = 1,
+};
+
 #endif