diff options
author | J. Bruce Fields <bfields@redhat.com> | 2011-09-28 17:37:56 +0200 |
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committer | J. Bruce Fields <bfields@redhat.com> | 2011-10-11 00:04:45 +0200 |
commit | 6409a5a65d2b959c3f5e2b8adfa67c349e294652 (patch) | |
tree | 82a765fd44662f4c334d0e639aa2e86341b847ba /fs/nfsd | |
parent | nfsd4: fix state lock usage in LOCKU (diff) | |
download | linux-6409a5a65d2b959c3f5e2b8adfa67c349e294652.tar.xz linux-6409a5a65d2b959c3f5e2b8adfa67c349e294652.zip |
nfsd4: clean up downgrading code
In response to some review comments, get rid of the somewhat obscure
for-loop with bitops, and improve a comment.
Reported-by: Steve Dickson <steved@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Diffstat (limited to 'fs/nfsd')
-rw-r--r-- | fs/nfsd/nfs4state.c | 31 | ||||
-rw-r--r-- | fs/nfsd/state.h | 8 |
2 files changed, 27 insertions, 12 deletions
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 8e253a347649..683885b18ceb 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -3523,16 +3523,29 @@ out: return status; } -static inline void nfs4_file_downgrade(struct nfs4_ol_stateid *stp, unsigned int to_access) +static inline void nfs4_stateid_downgrade_bit(struct nfs4_ol_stateid *stp, u32 access) { - int i; + if (!test_bit(access, &stp->st_access_bmap)) + return; + nfs4_file_put_access(stp->st_file, nfs4_access_to_omode(access)); + __clear_bit(access, &stp->st_access_bmap); +} - for (i = 1; i < 4; i++) { - if (test_bit(i, &stp->st_access_bmap) - && ((i & to_access) != i)) { - nfs4_file_put_access(stp->st_file, nfs4_access_to_omode(i)); - __clear_bit(i, &stp->st_access_bmap); - } +static inline void nfs4_stateid_downgrade(struct nfs4_ol_stateid *stp, u32 to_access) +{ + switch (to_access) { + case NFS4_SHARE_ACCESS_READ: + nfs4_stateid_downgrade_bit(stp, NFS4_SHARE_ACCESS_WRITE); + nfs4_stateid_downgrade_bit(stp, NFS4_SHARE_ACCESS_BOTH); + break; + case NFS4_SHARE_ACCESS_WRITE: + nfs4_stateid_downgrade_bit(stp, NFS4_SHARE_ACCESS_READ); + nfs4_stateid_downgrade_bit(stp, NFS4_SHARE_ACCESS_BOTH); + break; + case NFS4_SHARE_ACCESS_BOTH: + break; + default: + BUG(); } } @@ -3578,7 +3591,7 @@ nfsd4_open_downgrade(struct svc_rqst *rqstp, stp->st_deny_bmap, od->od_share_deny); goto out; } - nfs4_file_downgrade(stp, od->od_share_access); + nfs4_stateid_downgrade(stp, od->od_share_access); reset_union_bmap_deny(od->od_share_deny, &stp->st_deny_bmap); diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h index 13f6f9f5ceec..22b065a55ea0 100644 --- a/fs/nfsd/state.h +++ b/fs/nfsd/state.h @@ -403,9 +403,11 @@ struct nfs4_file { /* One each for O_RDONLY, O_WRONLY, O_RDWR: */ struct file * fi_fds[3]; /* - * Each open or lock stateid contributes 1 to either - * fi_access[O_RDONLY], fi_access[O_WRONLY], or both, depending - * on open or lock mode: + * Each open or lock stateid contributes 0-4 to the counts + * below depending on which bits are set in st_access_bitmap: + * 1 to fi_access[O_RDONLY] if NFS4_SHARE_ACCES_READ is set + * + 1 to fi_access[O_WRONLY] if NFS4_SHARE_ACCESS_WRITE is set + * + 1 to both of the above if NFS4_SHARE_ACCESS_BOTH is set. */ atomic_t fi_access[2]; struct file *fi_deleg_file; |