diff options
Diffstat (limited to 'sys/nfs/nfsnode.h')
| -rw-r--r-- | sys/nfs/nfsnode.h | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/sys/nfs/nfsnode.h b/sys/nfs/nfsnode.h index 3bc818f..1ca4529 100644 --- a/sys/nfs/nfsnode.h +++ b/sys/nfs/nfsnode.h @@ -118,6 +118,7 @@ struct nfsnode { short n_fhsize; /* size in bytes, of fh */ short n_flag; /* Flag for locking.. */ nfsfh_t n_fh; /* Small File Handle */ + struct lock n_rslock; }; #define n_atim n_un1.nf_atim @@ -157,6 +158,31 @@ extern struct proc *nfs_iodwant[NFS_MAXASYNCDAEMON]; extern struct nfsmount *nfs_iodmount[NFS_MAXASYNCDAEMON]; #if defined(KERNEL) || defined(_KERNEL) + +/* + * nfs_rslock - Attempt to obtain lock on nfsnode + * + * Attempt to obtain a lock on the passed nfsnode, returning ENOLCK + * if the lock could not be obtained due to our having to sleep. This + * function is generally used to lock around code that modifies an + * NFS file's size. In order to avoid deadlocks the lock + * should not be obtained while other locks are being held. + */ + +static __inline +int +nfs_rslock(struct nfsnode *np, struct proc *p) +{ + return(lockmgr(&np->n_rslock, LK_EXCLUSIVE | LK_CANRECURSE | LK_SLEEPFAIL, NULL, p)); +} + +static __inline +void +nfs_rsunlock(struct nfsnode *np, struct proc *p) +{ + (void)lockmgr(&np->n_rslock, LK_RELEASE, NULL, p); +} + extern vop_t **fifo_nfsv2nodeop_p; extern vop_t **nfsv2_vnodeop_p; extern vop_t **spec_nfsv2nodeop_p; |
