diff --git a/misc-utils/wipefs.8 b/misc-utils/wipefs.8 index c26b7890f..3874e1a7f 100644 --- a/misc-utils/wipefs.8 +++ b/misc-utils/wipefs.8 @@ -38,7 +38,8 @@ in environments where a stable output is required. .B wipefs calls the BLKRRPART ioctl when it has erased a partition-table signature -to inform the kernel about the change. +to inform the kernel about the change. The ioctl is called as the last step +and when all specified signatures from all specified devices are already erased. Note that some filesystems and some partition tables store more magic strings on the device (e.g. FAT, ZFS, GPT). The diff --git a/misc-utils/wipefs.c b/misc-utils/wipefs.c index 76149d9fc..49c5c8ca1 100644 --- a/misc-utils/wipefs.c +++ b/misc-utils/wipefs.c @@ -62,12 +62,17 @@ struct wipe_desc { }; struct wipe_control { - const char *devname; + char *devname; const char *type_pattern; /* -t */ struct libscols_table *outtab; struct wipe_desc *offsets; /* -o -o ... */ + size_t ndevs; /* number of devices to probe */ + + char **reread; /* devices to BLKRRPART */ + size_t nrereads; /* size of reread */ + unsigned int noact : 1, all : 1, quiet : 1, @@ -504,12 +509,25 @@ err: static void rereadpt(int fd, const char *devname) { struct stat st; + int try = 0; if (fstat(fd, &st) || !S_ISBLK(st.st_mode)) return; - errno = 0; - ioctl(fd, BLKRRPART); + do { + /* + * Unfortunately, it's pretty common that the first re-read + * without delay is uncuccesful. The reason is probably kernel + * and/or udevd. Let's wait a moment and try more attempts. + */ + xusleep(25000); + + errno = 0; + ioctl(fd, BLKRRPART); + if (errno != EBUSY) + break; + } while (try++ < 4); + printf(_("%s: calling ioctl to re-read partition table: %m\n"), devname); } #endif @@ -590,8 +608,21 @@ static int do_wipe(struct wipe_control *ctl) fsync(blkid_probe_get_fd(pr)); #ifdef BLKRRPART - if (reread && (mode & O_EXCL)) - rereadpt(blkid_probe_get_fd(pr), ctl->devname); + if (reread && (mode & O_EXCL)) { + if (ctl->ndevs > 1) { + /* + * We're going to probe more device, let's postpone + * re-read PT ioctl until all is erased to avoid + * situation we erase PT on /dev/sda before /dev/sdaN + * devices are processed. + */ + if (!ctl->reread) + ctl->reread = xcalloc(ctl->ndevs, sizeof(char *)); + + ctl->reread[ctl->nrereads++] = ctl->devname; + } else + rereadpt(blkid_probe_get_fd(pr), ctl->devname); + } #endif close(blkid_probe_get_fd(pr)); @@ -771,11 +802,28 @@ main(int argc, char **argv) /* * Erase */ + size_t i; + ctl.ndevs = argc - optind; + while (optind < argc) { ctl.devname = argv[optind++]; do_wipe(&ctl); + ctl.ndevs--; } - } + /* Re-read partition tables on whole-disk devices. This is + * postponed until all is done to avoid conflicts. + */ + for (i = 0; i < ctl.nrereads; i++) { + char *devname = ctl.reread[i]; + int fd = open(devname, O_RDONLY); + + if (fd >= 0) { + rereadpt(fd, devname); + close(fd); + } + } + free(ctl.reread); + } return EXIT_SUCCESS; }