diff options
| -rw-r--r-- | partx/Makefile.am | 2 | ||||
| -rw-r--r-- | partx/partx.c | 79 |
2 files changed, 79 insertions, 2 deletions
diff --git a/partx/Makefile.am b/partx/Makefile.am index 6a72942fe..080bc47ea 100644 --- a/partx/Makefile.am +++ b/partx/Makefile.am @@ -11,6 +11,8 @@ partx_SOURCES = partx.c partx.h \ $(top_srcdir)/lib/at.c \ $(top_srcdir)/lib/mbsalign.c \ $(top_srcdir)/lib/strutils.c \ + $(top_srcdir)/lib/canonicalize.c \ + $(top_srcdir)/lib/loopdev.c \ $(top_srcdir)/lib/linux_version.c partx_CFLAGS = -I$(ul_libblkid_incdir) diff --git a/partx/partx.c b/partx/partx.c index ca1934404..3a9da9e90 100644 --- a/partx/partx.c +++ b/partx/partx.c @@ -31,6 +31,7 @@ #include "xalloc.h" #include "partx.h" #include "sysfs.h" +#include "loopdev.h" #include "at.h" /* this is the default upper limit, could be modified by --nr */ @@ -88,7 +89,51 @@ static int columns[__NCOLUMNS], ncolumns; static int verbose; static int partx_flags; +static struct loopdev_cxt lc; +static int loopdev; +/* + * Check if the kernel supports partitioned loop devices. + * In a near future (around linux 3.2, hopefully) this will come + * always out of the box, until then we need to check. + */ +static int loopmod_supports_parts(void) +{ + int rc, ret = 0; + FILE *f = fopen("/sys/module/loop/parameters/max_part", "r"); + + if (!f) + return 0; + rc = fscanf(f, "%d", &ret); + fclose(f); + return rc = 1 ? ret : 0; +} + +static void assoc_loopdev(const char *fname) +{ + int rc; + + loopcxt_init(&lc, 0); + + rc = loopcxt_find_unused(&lc); + if (rc) + err(EXIT_FAILURE, _("%s: failed to find unused loop device"), + fname); + + if (verbose) + printf(_("Trying to use '%s' for the loop device\n"), + loopcxt_get_device(&lc)); + + if (loopcxt_set_backing_file(&lc, fname)) + err(EXIT_FAILURE, _("%s: failed to set backing file"), fname); + + rc = loopcxt_setup_device(&lc); + + if (rc == -EBUSY) + err(EXIT_FAILURE, _("%s: failed to setup loop device"), fname); + + loopdev = 1; +} static inline int get_column_id(int num) { @@ -278,6 +323,7 @@ static int del_parts(int fd, const char *device, dev_t devno, return rc; } + static void add_parts_warnx(const char *device, int first, int last) { if (first == last) @@ -288,7 +334,7 @@ static void add_parts_warnx(const char *device, int first, int last) } static int add_parts(int fd, const char *device, - blkid_partlist ls, int lower, int upper) + blkid_partlist ls, int lower, int upper) { int i, nparts, rc = 0, errfirst = 0, errlast = 0; @@ -338,6 +384,19 @@ static int add_parts(int fd, const char *device, if (errfirst) add_parts_warnx(device, errfirst, errlast); + + /* the kernel adds *all* loopdev partitions, so we should delete + any extra, unwanted ones, when the -n option is passed */ + if (loopdev && (lower || upper)) { + for (i = 0; i < nparts; i++) { + blkid_partition par = blkid_partlist_get_partition(ls, i); + int n = blkid_partition_get_partno(par); + + if (n < lower || n > upper) + partx_del_partition(fd, n); + } + } + return rc; } @@ -799,7 +858,20 @@ int main(int argc, char **argv) if (what == ACT_ADD || what == ACT_DELETE) { struct stat x; - if (stat(wholedisk, &x) || !S_ISBLK(x.st_mode)) + if (stat(wholedisk, &x)) + errx(EXIT_FAILURE, "%s", wholedisk); + + if (S_ISREG(x.st_mode)) { + /* not a blkdev, try to associate it to a loop device */ + if (what == ACT_DELETE) + errx(EXIT_FAILURE, _("%s: cannot delete partitions"), + wholedisk); + if (!loopmod_supports_parts()) + errx(EXIT_FAILURE, _("%s: partitioned loop devices unsupported"), + wholedisk); + assoc_loopdev(wholedisk); + wholedisk = xstrdup(lc.device); + } else if (!S_ISBLK(x.st_mode)) errx(EXIT_FAILURE, _("%s: not a block device"), wholedisk); } if ((fd = open(wholedisk, O_RDONLY)) == -1) @@ -845,6 +917,9 @@ int main(int argc, char **argv) blkid_free_probe(pr); } + if (loopdev) + loopcxt_deinit(&lc); + close(fd); return rc ? EXIT_FAILURE : EXIT_SUCCESS; } |