From 94ec938b612eb877bb6622847972dd739ef738b8 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Tue, 17 Jun 2014 07:44:14 -0400 Subject: [PATCH] nfsd: add appropriate __force directives to filehandle generation code The filehandle structs all use host-endian values, but will sometimes stuff big-endian values into those fields. This is OK since these values are opaque to the client, but it confuses sparse. Add __force to make it clear that we are doing this intentionally. Signed-off-by: Jeff Layton Reviewed-by: Christoph Hellwig Signed-off-by: J. Bruce Fields --- fs/nfsd/nfsfh.c | 9 ++++++++- fs/nfsd/nfsfh.h | 15 +++++++++++---- 2 files changed, 19 insertions(+), 5 deletions(-) diff --git a/fs/nfsd/nfsfh.c b/fs/nfsd/nfsfh.c index 6f5cc76a6c6e..e883a5868be6 100644 --- a/fs/nfsd/nfsfh.c +++ b/fs/nfsd/nfsfh.c @@ -162,7 +162,14 @@ static __be32 nfsd_set_fh_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp) /* deprecated, convert to type 3 */ len = key_len(FSID_ENCODE_DEV)/4; fh->fh_fsid_type = FSID_ENCODE_DEV; - fh->fh_fsid[0] = new_encode_dev(MKDEV(ntohl(fh->fh_fsid[0]), ntohl(fh->fh_fsid[1]))); + /* + * struct knfsd_fh uses host-endian fields, which are + * sometimes used to hold net-endian values. This + * confuses sparse, so we must use __force here to + * keep it from complaining. + */ + fh->fh_fsid[0] = new_encode_dev(MKDEV(ntohl((__force __be32)fh->fh_fsid[0]), + ntohl((__force __be32)fh->fh_fsid[1]))); fh->fh_fsid[1] = fh->fh_fsid[2]; } data_left -= len; diff --git a/fs/nfsd/nfsfh.h b/fs/nfsd/nfsfh.h index 2e89e70ac15c..08236d70c667 100644 --- a/fs/nfsd/nfsfh.h +++ b/fs/nfsd/nfsfh.h @@ -73,8 +73,15 @@ enum fsid_source { extern enum fsid_source fsid_source(struct svc_fh *fhp); -/* This might look a little large to "inline" but in all calls except +/* + * This might look a little large to "inline" but in all calls except * one, 'vers' is constant so moste of the function disappears. + * + * In some cases the values are considered to be host endian and in + * others, net endian. fsidv is always considered to be u32 as the + * callers don't know which it will be. So we must use __force to keep + * sparse from complaining. Since these values are opaque to the + * client, that shouldn't be a problem. */ static inline void mk_fsid(int vers, u32 *fsidv, dev_t dev, ino_t ino, u32 fsid, unsigned char *uuid) @@ -82,7 +89,7 @@ static inline void mk_fsid(int vers, u32 *fsidv, dev_t dev, ino_t ino, u32 *up; switch(vers) { case FSID_DEV: - fsidv[0] = htonl((MAJOR(dev)<<16) | + fsidv[0] = (__force __u32)htonl((MAJOR(dev)<<16) | MINOR(dev)); fsidv[1] = ino_t_to_u32(ino); break; @@ -90,8 +97,8 @@ static inline void mk_fsid(int vers, u32 *fsidv, dev_t dev, ino_t ino, fsidv[0] = fsid; break; case FSID_MAJOR_MINOR: - fsidv[0] = htonl(MAJOR(dev)); - fsidv[1] = htonl(MINOR(dev)); + fsidv[0] = (__force __u32)htonl(MAJOR(dev)); + fsidv[1] = (__force __u32)htonl(MINOR(dev)); fsidv[2] = ino_t_to_u32(ino); break; -- 2.20.1