Hey Chuck, On 12/06/2010 11:09 AM, Chuck Lever wrote: > Monitored host information is stored in files under /var/lib/nfs. > When visiting entries in the monitored hosts directory, libnsm.a > examines the value of dirent.d_type to determine if an entry is a > regular file. > > According to readdir(3), the d_type field is not supported by all > file system types. My root file system happens to be one where d_type > isn't supported. Typical installations that use an ext-derived root > file system are not exposed to this issue, but those who use xfs, for > instance, are. > > On such file systems, not only are remote peers not notified of > reboots, but the NSM state number is never incremented. A statd warm > restart would not re-monitor any hosts that were monitored before > the restart. > > When writing support/nsm/file.c, I copied the use of d_type from the > original statd code, so this has likely been an issue for some time. > > Replace the use of d_type in support/nsm/file.c with a call to > lstat(2). It's extra code, but is guaranteed to work on all file > system types. > > Note there is a usage of d_type in gssd. I'll let gssd and rpcpipefs > experts decide whether that's worth changing. > > Fix for: > > https://bugzilla.linux-nfs.org/show_bug.cgi?id=193 > > Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx> > --- > > support/nsm/file.c | 38 ++++++++++++++++++++++++++++++-------- > 1 files changed, 30 insertions(+), 8 deletions(-) > > diff --git a/support/nsm/file.c b/support/nsm/file.c > index f4baeb9..ba2a9ce 100644 > --- a/support/nsm/file.c > +++ b/support/nsm/file.c > @@ -568,11 +568,13 @@ nsm_retire_monitored_hosts(void) > > while ((de = readdir(dir)) != NULL) { > char *src, *dst; > + struct stat stb; > > - if (de->d_type != (unsigned char)DT_REG) > - continue; > - if (de->d_name[0] == '.') > + if (de->d_name[0] == '.') { > + xlog(D_GENERAL, "Skipping dot file %s", > + de->d_name); > continue; > + } > > src = nsm_make_record_pathname(NSM_MONITOR_DIR, de->d_name); > if (src == NULL) { > @@ -580,6 +582,20 @@ nsm_retire_monitored_hosts(void) > continue; > } > > + /* NB: not all file systems fill in d_type correctly */ > + if (lstat(src, &stb) == -1) { > + xlog_warn("Bad monitor file %s, skipping: %m", > + de->d_name); > + free(src); > + continue; > + } > + if (!S_ISREG(stb.st_mode)) { > + xlog(D_GENERAL, "Skipping non-regular file %s", > + de->d_name); > + free(src); > + continue; > + } > + > dst = nsm_make_record_pathname(NSM_NOTIFY_DIR, de->d_name); > if (dst == NULL) { > free(src); > @@ -846,7 +862,7 @@ nsm_read_line(const char *hostname, const time_t timestamp, char *line, > } > > /* > - * Given a filename, reads data from a file under NSM_MONITOR_DIR > + * Given a filename, reads data from a file under "directory" > * and invokes @func so caller can populate their in-core > * database with this data. > */ > @@ -863,10 +879,15 @@ nsm_load_host(const char *directory, const char *filename, nsm_populate_t func) > if (path == NULL) > goto out_err; > > - if (stat(path, &stb) == -1) { > + if (lstat(path, &stb) == -1) { > xlog(L_ERROR, "Failed to stat %s: %m", path); > goto out_freepath; > } > + if (!S_ISREG(stb.st_mode)) { > + xlog(D_GENERAL, "Skipping non-regular file %s", > + path); Question, why do we care non-regular files are being ignored? I understand logging the lstat() error but logging statements like "ignoring this" or "not doing that" just make the debug output a bit too noisy IMHO... I'm thinking it would be better to log the files that are actually being used verses files that are being ignored. > + goto out_freepath; > + } > > f = fopen(path, "r"); > if (f == NULL) { > @@ -913,10 +934,11 @@ nsm_load_dir(const char *directory, nsm_populate_t func) > } > > while ((de = readdir(dir)) != NULL) { > - if (de->d_type != (unsigned char)DT_REG) > - continue; > - if (de->d_name[0] == '.') > + if (de->d_name[0] == '.') { > + xlog(D_GENERAL, "Skipping dot file %s", > + de->d_name); The same goes with this... Do we really care "." and ".." are being ignored? Isn't that expected? ;-) steved. > continue; > + } > > count += nsm_load_host(directory, de->d_name, func); > } > -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
