Commit 832738e4 authored by Sergey Bashirov's avatar Sergey Bashirov Committed by Chuck Lever
Browse files

NFSD: Rework encoding and decoding of nfsd4_deviceid 



Compilers may optimize the layout of C structures, so we should not rely
on sizeof struct and memcpy to encode and decode XDR structures. The byte
order of the fields should also be taken into account.

This patch adds the correct functions to handle the deviceid4 structure
and removes the pad field, which is currently not used by NFSD, from the
runtime state. The server's byte order is preserved because the deviceid4
blob on the wire is only used as a cookie by the client.

Signed-off-by: default avatarSergey Bashirov <sergeybashirov@gmail.com>
Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
parent c97b737e

fs/nfsd/blocklayoutxdr.c

+2 −5
Original line number Diff line number Diff line
@@ -29,8 +29,7 @@ nfsd4_block_encode_layoutget(struct xdr_stream *xdr, 
	*p++ = cpu_to_be32(len);

	*p++ = cpu_to_be32(1);		/* we always return a single extent */



	p = xdr_encode_opaque_fixed(p, &b->vol_id,

			sizeof(struct nfsd4_deviceid));

	p = svcxdr_encode_deviceid4(p, &b->vol_id);

	p = xdr_encode_hyper(p, b->foff);

	p = xdr_encode_hyper(p, b->len);

	p = xdr_encode_hyper(p, b->soff);
@@ -156,9 +155,7 @@ nfsd4_block_decode_layoutupdate(__be32 *p, u32 len, struct iomap **iomapp, 
	for (i = 0; i < nr_iomaps; i++) {

		struct pnfs_block_extent bex;



		memcpy(&bex.vol_id, p, sizeof(struct nfsd4_deviceid));

		p += XDR_QUADLEN(sizeof(struct nfsd4_deviceid));



		p = svcxdr_decode_deviceid4(p, &bex.vol_id);

		p = xdr_decode_hyper(p, &bex.foff);

		if (bex.foff & (block_size - 1)) {

			goto fail;

fs/nfsd/flexfilelayoutxdr.c

+1 −2
Original line number Diff line number Diff line
@@ -54,8 +54,7 @@ nfsd4_ff_encode_layoutget(struct xdr_stream *xdr, 
	*p++ = cpu_to_be32(1);			/* single mirror */

	*p++ = cpu_to_be32(1);			/* single data server */



	p = xdr_encode_opaque_fixed(p, &fl->deviceid,

			sizeof(struct nfsd4_deviceid));

	p = svcxdr_encode_deviceid4(p, &fl->deviceid);



	*p++ = cpu_to_be32(1);			/* efficiency */

fs/nfsd/nfs4layouts.c

+0 −1
Original line number Diff line number Diff line
@@ -120,7 +120,6 @@ nfsd4_set_deviceid(struct nfsd4_deviceid *id, const struct svc_fh *fhp, 


	id->fsid_idx = fhp->fh_export->ex_devid_map->idx;

	id->generation = device_generation;

	id->pad = 0;

	return 0;

}

fs/nfsd/nfs4xdr.c

+1 −13
Original line number Diff line number Diff line
@@ -587,18 +587,6 @@ nfsd4_decode_state_owner4(struct nfsd4_compoundargs *argp, 
}



#ifdef CONFIG_NFSD_PNFS

static __be32

nfsd4_decode_deviceid4(struct nfsd4_compoundargs *argp,

		       struct nfsd4_deviceid *devid)

{

	__be32 *p;



	p = xdr_inline_decode(argp->xdr, NFS4_DEVICEID4_SIZE);

	if (!p)

		return nfserr_bad_xdr;

	memcpy(devid, p, sizeof(*devid));

	return nfs_ok;

}



static __be32

nfsd4_decode_layoutupdate4(struct nfsd4_compoundargs *argp,
@@ -1783,7 +1771,7 @@ nfsd4_decode_getdeviceinfo(struct nfsd4_compoundargs *argp, 
	__be32 status;



	memset(gdev, 0, sizeof(*gdev));

	status = nfsd4_decode_deviceid4(argp, &gdev->gd_devid);

	status = nfsd4_decode_deviceid4(argp->xdr, &gdev->gd_devid);

	if (status)

		return status;

	if (xdr_stream_decode_u32(argp->xdr, &gdev->gd_layout_type) < 0)

fs/nfsd/xdr4.h

+35 −1
Original line number Diff line number Diff line
@@ -595,9 +595,43 @@ struct nfsd4_reclaim_complete { 
struct nfsd4_deviceid {

	u64			fsid_idx;

	u32			generation;

	u32			pad;

};



static inline __be32 *

svcxdr_encode_deviceid4(__be32 *p, const struct nfsd4_deviceid *devid)

{

	__be64 *q = (__be64 *)p;



	*q = (__force __be64)devid->fsid_idx;

	p += 2;

	*p++ = (__force __be32)devid->generation;

	*p++ = xdr_zero;

	return p;

}



static inline __be32 *

svcxdr_decode_deviceid4(__be32 *p, struct nfsd4_deviceid *devid)

{

	__be64 *q = (__be64 *)p;



	devid->fsid_idx = (__force u64)(*q);

	p += 2;

	devid->generation = (__force u32)(*p++);

	p++; /* NFSD does not use the remaining octets */

	return p;

}



static inline __be32

nfsd4_decode_deviceid4(struct xdr_stream *xdr, struct nfsd4_deviceid *devid)

{

	__be32 *p = xdr_inline_decode(xdr, NFS4_DEVICEID4_SIZE);



	if (unlikely(!p))

		return nfserr_bad_xdr;

	svcxdr_decode_deviceid4(p, devid);

	return nfs_ok;

}



struct nfsd4_layout_seg {

	u32			iomode;

	u64			offset;