diff options
| -rw-r--r-- | fs/nfsd/nfsfh.c | 30 |
1 files changed, 24 insertions, 6 deletions
diff --git a/fs/nfsd/nfsfh.c b/fs/nfsd/nfsfh.c index f0da7d9c3a9..019a8a20184 100644 --- a/fs/nfsd/nfsfh.c +++ b/fs/nfsd/nfsfh.c @@ -258,14 +258,32 @@ out: return error; } -/* - * Perform sanity checks on the dentry in a client's file handle. +/** + * fh_verify - filehandle lookup and access checking + * @rqstp: pointer to current rpc request + * @fhp: filehandle to be verified + * @type: expected type of object pointed to by filehandle + * @access: type of access needed to object + * + * Look up a dentry from the on-the-wire filehandle, check the client's + * access to the export, and set the current task's credentials. + * + * Regardless of success or failure of fh_verify(), fh_put() should be + * called on @fhp when the caller is finished with the filehandle. + * + * fh_verify() may be called multiple times on a given filehandle, for + * example, when processing an NFSv4 compound. The first call will look + * up a dentry using the on-the-wire filehandle. Subsequent calls will + * skip the lookup and just perform the other checks and possibly change + * the current task's credentials. * - * Note that the file handle dentry may need to be freed even after - * an error return. + * @type specifies the type of object expected using one of the S_IF* + * constants defined in include/linux/stat.h. The caller may use zero + * to indicate that it doesn't care, or a negative integer to indicate + * that it expects something not of the given type. * - * This is only called at the start of an nfsproc call, so fhp points to - * a svc_fh which is all 0 except for the over-the-wire file handle. + * @access is formed from the NFSD_MAY_* constants defined in + * include/linux/nfsd/nfsd.h. */ __be32 fh_verify(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, int access) |