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: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index ba952bd..7310d2e 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -1452,26 +1452,25 @@
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 @@
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 @@
{
int status;
umode_t fmode = 0;
- uint64_t fileid;
uint32_t type;
status = decode_attr_type(xdr, bitmap, &type);
@@ -4101,13 +4099,10 @@
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;
- }
+ fattr->valid |= status;
xdr_error:
dprintk("%s: xdr returned %d\n", __func__, -status);
@@ -6411,7 +6406,9 @@
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;
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 78b101e..890dce2 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -50,6 +50,7 @@
} du;
struct nfs_fsid fsid;
__u64 fileid;
+ __u64 mounted_on_fileid;
struct timespec atime;
struct timespec mtime;
struct timespec ctime;
@@ -83,6 +84,7 @@
#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 \