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 <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index c02bad6..f7f1163 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -721,42 +721,58 @@
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 @@
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;
}