From c11c591fe6682e0d642bf9242e53554a50e5fbc0 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Thu, 10 Jul 2014 14:07:30 -0400 Subject: [PATCH] nfsd: shrink st_access_bmap and st_deny_bmap We never use anything above bit #3, so an unsigned long for each is wasteful. Shrink them to a char each, and add some WARN_ON_ONCE calls if we try to set or clear bits that would go outside those sizes. Note too that because atomic bitops work on unsigned longs, we have to abandon their use here. That shouldn't be a problem though since we don't really care about the atomicity in this code anyway. Using them was just a convenient way to flip bits. Signed-off-by: Jeff Layton Reviewed-by: Christoph Hellwig Signed-off-by: J. Bruce Fields --- fs/nfsd/nfs4state.c | 38 +++++++++++++++++++++++++++----------- fs/nfsd/state.h | 4 ++-- 2 files changed, 29 insertions(+), 13 deletions(-) diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index c02bad6d7e90..f7f11631c26c 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -721,42 +721,58 @@ test_share(struct nfs4_ol_stateid *stp, struct nfsd4_open *open) { static inline void set_access(u32 access, struct nfs4_ol_stateid *stp) { - __set_bit(access, &stp->st_access_bmap); + unsigned char mask = 1 << access; + + WARN_ON_ONCE(access > NFS4_SHARE_ACCESS_BOTH); + stp->st_access_bmap |= mask; } /* clear share access for a given stateid */ static inline void clear_access(u32 access, struct nfs4_ol_stateid *stp) { - __clear_bit(access, &stp->st_access_bmap); + unsigned char mask = 1 << access; + + WARN_ON_ONCE(access > NFS4_SHARE_ACCESS_BOTH); + stp->st_access_bmap &= ~mask; } /* test whether a given stateid has access */ static inline bool test_access(u32 access, struct nfs4_ol_stateid *stp) { - return test_bit(access, &stp->st_access_bmap); + unsigned char mask = 1 << access; + + return (bool)(stp->st_access_bmap & mask); } /* set share deny for a given stateid */ static inline void -set_deny(u32 access, struct nfs4_ol_stateid *stp) +set_deny(u32 deny, struct nfs4_ol_stateid *stp) { - __set_bit(access, &stp->st_deny_bmap); + unsigned char mask = 1 << deny; + + WARN_ON_ONCE(deny > NFS4_SHARE_DENY_BOTH); + stp->st_deny_bmap |= mask; } /* clear share deny for a given stateid */ static inline void -clear_deny(u32 access, struct nfs4_ol_stateid *stp) +clear_deny(u32 deny, struct nfs4_ol_stateid *stp) { - __clear_bit(access, &stp->st_deny_bmap); + unsigned char mask = 1 << deny; + + WARN_ON_ONCE(deny > NFS4_SHARE_DENY_BOTH); + stp->st_deny_bmap &= ~mask; } /* test whether a given stateid is denying specific access */ static inline bool -test_deny(u32 access, struct nfs4_ol_stateid *stp) +test_deny(u32 deny, struct nfs4_ol_stateid *stp) { - return test_bit(access, &stp->st_deny_bmap); + unsigned char mask = 1 << deny; + + return (bool)(stp->st_deny_bmap & mask); } static int nfs4_access_to_omode(u32 access) @@ -4282,12 +4298,12 @@ nfsd4_open_downgrade(struct svc_rqst *rqstp, goto out; status = nfserr_inval; if (!test_access(od->od_share_access, stp)) { - dprintk("NFSD: access not a subset current bitmap: 0x%lx, input access=%08x\n", + dprintk("NFSD: access not a subset of current bitmap: 0x%hhx, input access=%08x\n", stp->st_access_bmap, od->od_share_access); goto out; } if (!test_deny(od->od_share_deny, stp)) { - dprintk("NFSD:deny not a subset current bitmap: 0x%lx, input deny=%08x\n", + dprintk("NFSD: deny not a subset of current bitmap: 0x%hhx, input deny=%08x\n", stp->st_deny_bmap, od->od_share_deny); goto out; } diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h index 9f1159d5de56..72aee4b4f1ae 100644 --- a/fs/nfsd/state.h +++ b/fs/nfsd/state.h @@ -406,8 +406,8 @@ struct nfs4_ol_stateid { struct list_head st_locks; struct nfs4_stateowner * st_stateowner; struct nfs4_file * st_file; - unsigned long st_access_bmap; - unsigned long st_deny_bmap; + unsigned char st_access_bmap; + unsigned char st_deny_bmap; struct nfs4_ol_stateid * st_openstp; }; -- GitLab