Commit 28331a46 authored by Trond Myklebust's avatar Trond Myklebust
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NFSv4: Ensure we request the ordinary fileid when doing readdirplus 



When readdir() returns a directory entry for the root of a mounted
filesystem, Linux follows the old convention of returning the inode
number of the covered directory (despite newer versions of POSIX declaring
that this is a bug).
To ensure this continues to work, the NFSv4 readdir implementation requests
the 'mounted-on-fileid' from the server.

However, readdirplus also needs to instantiate an inode for this entry, and
for that, we also need to request the real fileid as per this patch.

Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
parent 1bd714f2

fs/nfs/nfs4xdr.c

+14 −17
Original line number Diff line number Diff line
@@ -1452,26 +1452,25 @@ static void encode_read(struct xdr_stream *xdr, const struct nfs_readargs *args, 


static void encode_readdir(struct xdr_stream *xdr, const struct nfs4_readdir_arg *readdir, struct rpc_rqst *req, struct compound_hdr *hdr)

{

	uint32_t attrs[2] = {0, 0};

	uint32_t attrs[2] = {

		FATTR4_WORD0_RDATTR_ERROR,

		FATTR4_WORD1_MOUNTED_ON_FILEID,

	};

	uint32_t dircount = readdir->count >> 1;

	__be32 *p;



	if (readdir->plus) {

		attrs[0] |= FATTR4_WORD0_TYPE|FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE|

			FATTR4_WORD0_FSID|FATTR4_WORD0_FILEHANDLE;

			FATTR4_WORD0_FSID|FATTR4_WORD0_FILEHANDLE|FATTR4_WORD0_FILEID;

		attrs[1] |= FATTR4_WORD1_MODE|FATTR4_WORD1_NUMLINKS|FATTR4_WORD1_OWNER|

			FATTR4_WORD1_OWNER_GROUP|FATTR4_WORD1_RAWDEV|

			FATTR4_WORD1_SPACE_USED|FATTR4_WORD1_TIME_ACCESS|

			FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY;

		dircount >>= 1;

	}

	attrs[0] |= FATTR4_WORD0_RDATTR_ERROR|FATTR4_WORD0_FILEID;

	attrs[1] |= FATTR4_WORD1_MOUNTED_ON_FILEID;

	/* Switch to mounted_on_fileid if the server supports it */

	if (readdir->bitmask[1] & FATTR4_WORD1_MOUNTED_ON_FILEID)

		attrs[0] &= ~FATTR4_WORD0_FILEID;

	else

		attrs[1] &= ~FATTR4_WORD1_MOUNTED_ON_FILEID;

	/* Use mounted_on_fileid only if the server supports it */

	if (!(readdir->bitmask[1] & FATTR4_WORD1_MOUNTED_ON_FILEID))

		attrs[0] |= FATTR4_WORD0_FILEID;



	p = reserve_space(xdr, 12+NFS4_VERIFIER_SIZE+20);

	*p++ = cpu_to_be32(OP_READDIR);
@@ -3140,7 +3139,7 @@ static int decode_attr_mounted_on_fileid(struct xdr_stream *xdr, uint32_t *bitma 
			goto out_overflow;

		xdr_decode_hyper(p, fileid);

		bitmap[1] &= ~FATTR4_WORD1_MOUNTED_ON_FILEID;

		ret = NFS_ATTR_FATTR_FILEID;

		ret = NFS_ATTR_FATTR_MOUNTED_ON_FILEID;

	}

	dprintk("%s: fileid=%Lu\n", __func__, (unsigned long long)*fileid);

	return ret;
@@ -4002,7 +4001,6 @@ static int decode_getfattr_attrs(struct xdr_stream *xdr, uint32_t *bitmap, 
{

	int status;

	umode_t fmode = 0;

	uint64_t fileid;

	uint32_t type;



	status = decode_attr_type(xdr, bitmap, &type);
@@ -4101,13 +4099,10 @@ static int decode_getfattr_attrs(struct xdr_stream *xdr, uint32_t *bitmap, 
		goto xdr_error;

	fattr->valid |= status;



	status = decode_attr_mounted_on_fileid(xdr, bitmap, &fileid);

	status = decode_attr_mounted_on_fileid(xdr, bitmap, &fattr->mounted_on_fileid);

	if (status < 0)

		goto xdr_error;

	if (status != 0 && !(fattr->valid & status)) {

		fattr->fileid = fileid;

	fattr->valid |= status;

	}



xdr_error:

	dprintk("%s: xdr returned %d\n", __func__, -status);
@@ -6411,7 +6406,9 @@ int nfs4_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry, 
	if (decode_getfattr_attrs(xdr, bitmap, entry->fattr, entry->fh,

					entry->server, 1) < 0)

		goto out_overflow;

	if (entry->fattr->valid & NFS_ATTR_FATTR_FILEID)

	if (entry->fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID)

		entry->ino = entry->fattr->mounted_on_fileid;

	else if (entry->fattr->valid & NFS_ATTR_FATTR_FILEID)

		entry->ino = entry->fattr->fileid;



	entry->d_type = DT_UNKNOWN;

include/linux/nfs_xdr.h

+2 −0
Original line number Diff line number Diff line
@@ -50,6 +50,7 @@ struct nfs_fattr { 
	} du;

	struct nfs_fsid		fsid;

	__u64			fileid;

	__u64			mounted_on_fileid;

	struct timespec		atime;

	struct timespec		mtime;

	struct timespec		ctime;
@@ -83,6 +84,7 @@ struct nfs_fattr { 
#define NFS_ATTR_FATTR_PRECHANGE	(1U << 18)

#define NFS_ATTR_FATTR_V4_REFERRAL	(1U << 19)	/* NFSv4 referral */

#define NFS_ATTR_FATTR_MOUNTPOINT	(1U << 20)	/* Treat as mountpoint */

#define NFS_ATTR_FATTR_MOUNTED_ON_FILEID		(1U << 21)



#define NFS_ATTR_FATTR (NFS_ATTR_FATTR_TYPE \

		| NFS_ATTR_FATTR_MODE \

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