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-rw-r--r--sys-utils/losetup.c917
1 files changed, 917 insertions, 0 deletions
diff --git a/sys-utils/losetup.c b/sys-utils/losetup.c
new file mode 100644
index 0000000..7d14f56
--- /dev/null
+++ b/sys-utils/losetup.c
@@ -0,0 +1,917 @@
+/*
+ * Copyright (C) 2011 Karel Zak <kzak@redhat.com>
+ * Originally from Ted's losetup.c
+ *
+ * losetup.c - setup and control loop devices
+ */
+#include <assert.h>
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <inttypes.h>
+#include <getopt.h>
+
+#include <libsmartcols.h>
+
+#include "c.h"
+#include "nls.h"
+#include "strutils.h"
+#include "loopdev.h"
+#include "closestream.h"
+#include "optutils.h"
+#include "xalloc.h"
+#include "canonicalize.h"
+#include "pathnames.h"
+
+enum {
+ A_CREATE = 1, /* setup a new device */
+ A_DELETE, /* delete given device(s) */
+ A_DELETE_ALL, /* delete all devices */
+ A_SHOW, /* list devices */
+ A_SHOW_ONE, /* print info about one device */
+ A_FIND_FREE, /* find first unused */
+ A_SET_CAPACITY, /* set device capacity */
+ A_SET_DIRECT_IO, /* set accessing backing file by direct io */
+ A_SET_BLOCKSIZE, /* set logical block size of the loop device */
+};
+
+enum {
+ COL_NAME = 0,
+ COL_AUTOCLR,
+ COL_BACK_FILE,
+ COL_BACK_INO,
+ COL_BACK_MAJMIN,
+ COL_MAJMIN,
+ COL_OFFSET,
+ COL_PARTSCAN,
+ COL_RO,
+ COL_SIZELIMIT,
+ COL_DIO,
+ COL_LOGSEC,
+};
+
+/* basic output flags */
+static int no_headings;
+static int raw;
+static int json;
+
+struct colinfo {
+ const char *name;
+ double whint;
+ int flags;
+ const char *help;
+
+ int json_type; /* default is string */
+};
+
+static struct colinfo infos[] = {
+ [COL_AUTOCLR] = { "AUTOCLEAR", 1, SCOLS_FL_RIGHT, N_("autoclear flag set"), SCOLS_JSON_BOOLEAN},
+ [COL_BACK_FILE] = { "BACK-FILE", 0.3, 0, N_("device backing file")},
+ [COL_BACK_INO] = { "BACK-INO", 4, SCOLS_FL_RIGHT, N_("backing file inode number"), SCOLS_JSON_NUMBER},
+ [COL_BACK_MAJMIN] = { "BACK-MAJ:MIN", 6, 0, N_("backing file major:minor device number")},
+ [COL_NAME] = { "NAME", 0.25, 0, N_("loop device name")},
+ [COL_OFFSET] = { "OFFSET", 5, SCOLS_FL_RIGHT, N_("offset from the beginning"), SCOLS_JSON_NUMBER},
+ [COL_PARTSCAN] = { "PARTSCAN", 1, SCOLS_FL_RIGHT, N_("partscan flag set"), SCOLS_JSON_BOOLEAN},
+ [COL_RO] = { "RO", 1, SCOLS_FL_RIGHT, N_("read-only device"), SCOLS_JSON_BOOLEAN},
+ [COL_SIZELIMIT] = { "SIZELIMIT", 5, SCOLS_FL_RIGHT, N_("size limit of the file in bytes"), SCOLS_JSON_NUMBER},
+ [COL_MAJMIN] = { "MAJ:MIN", 3, 0, N_("loop device major:minor number")},
+ [COL_DIO] = { "DIO", 1, SCOLS_FL_RIGHT, N_("access backing file with direct-io"), SCOLS_JSON_BOOLEAN},
+ [COL_LOGSEC] = { "LOG-SEC", 4, SCOLS_FL_RIGHT, N_("logical sector size in bytes"), SCOLS_JSON_NUMBER},
+};
+
+static int columns[ARRAY_SIZE(infos) * 2] = {-1};
+static size_t ncolumns;
+
+static int get_column_id(int num)
+{
+ assert(num >= 0);
+ assert((size_t) num < ncolumns);
+ assert(columns[num] < (int) ARRAY_SIZE(infos));
+ return columns[num];
+}
+
+static struct colinfo *get_column_info(int num)
+{
+ return &infos[ get_column_id(num) ];
+}
+
+static int column_name_to_id(const char *name, size_t namesz)
+{
+ size_t i;
+
+ for (i = 0; i < ARRAY_SIZE(infos); i++) {
+ const char *cn = infos[i].name;
+
+ if (!strncasecmp(name, cn, namesz) && !*(cn + namesz))
+ return i;
+ }
+ warnx(_("unknown column: %s"), name);
+ return -1;
+}
+
+static int printf_loopdev(struct loopdev_cxt *lc)
+{
+ uint64_t x;
+ dev_t dev = 0;
+ ino_t ino = 0;
+ char *fname;
+ uint32_t type;
+
+ fname = loopcxt_get_backing_file(lc);
+ if (!fname)
+ return -EINVAL;
+
+ if (loopcxt_get_backing_devno(lc, &dev) == 0)
+ loopcxt_get_backing_inode(lc, &ino);
+
+ if (!dev && !ino) {
+ /*
+ * Probably non-root user (no permissions to
+ * call LOOP_GET_STATUS ioctls).
+ */
+ printf("%s: []: (%s)",
+ loopcxt_get_device(lc), fname);
+
+ if (loopcxt_get_offset(lc, &x) == 0 && x)
+ printf(_(", offset %ju"), x);
+
+ if (loopcxt_get_sizelimit(lc, &x) == 0 && x)
+ printf(_(", sizelimit %ju"), x);
+ goto done;
+ }
+
+ printf("%s: [%04d]:%" PRIu64 " (%s)",
+ loopcxt_get_device(lc), (int) dev, ino, fname);
+
+ if (loopcxt_get_offset(lc, &x) == 0 && x)
+ printf(_(", offset %ju"), x);
+
+ if (loopcxt_get_sizelimit(lc, &x) == 0 && x)
+ printf(_(", sizelimit %ju"), x);
+
+ if (loopcxt_get_encrypt_type(lc, &type) == 0) {
+ const char *e = loopcxt_get_crypt_name(lc);
+
+ if ((!e || !*e) && type == 1)
+ e = "XOR";
+ if (e && *e)
+ printf(_(", encryption %s (type %u)"), e, type);
+ }
+
+done:
+ free(fname);
+ printf("\n");
+ return 0;
+}
+
+static int show_all_loops(struct loopdev_cxt *lc, const char *file,
+ uint64_t offset, int flags)
+{
+ struct stat sbuf, *st = &sbuf;
+ char *cn_file = NULL;
+
+ if (loopcxt_init_iterator(lc, LOOPITER_FL_USED))
+ return -1;
+
+ if (!file || stat(file, st))
+ st = NULL;
+
+ while (loopcxt_next(lc) == 0) {
+ if (file) {
+ int used;
+ const char *bf = cn_file ? cn_file : file;
+
+ used = loopcxt_is_used(lc, st, bf, offset, 0, flags);
+ if (!used && !cn_file) {
+ bf = cn_file = canonicalize_path(file);
+ used = loopcxt_is_used(lc, st, bf, offset, 0, flags);
+ }
+ if (!used)
+ continue;
+ }
+ printf_loopdev(lc);
+ }
+ loopcxt_deinit_iterator(lc);
+ free(cn_file);
+ return 0;
+}
+
+static int delete_loop(struct loopdev_cxt *lc)
+{
+ if (loopcxt_delete_device(lc))
+ warn(_("%s: detach failed"), loopcxt_get_device(lc));
+ else
+ return 0;
+
+ return -1;
+}
+
+static int delete_all_loops(struct loopdev_cxt *lc)
+{
+ int res = 0;
+
+ if (loopcxt_init_iterator(lc, LOOPITER_FL_USED))
+ return -1;
+
+ while (loopcxt_next(lc) == 0)
+ res += delete_loop(lc);
+
+ loopcxt_deinit_iterator(lc);
+ return res;
+}
+
+static int set_scols_data(struct loopdev_cxt *lc, struct libscols_line *ln)
+{
+ size_t i;
+
+ for (i = 0; i < ncolumns; i++) {
+ const char *p = NULL; /* external data */
+ char *np = NULL; /* allocated here */
+ uint64_t x = 0;
+ int rc = 0;
+
+ switch(get_column_id(i)) {
+ case COL_NAME:
+ p = loopcxt_get_device(lc);
+ break;
+ case COL_BACK_FILE:
+ p = loopcxt_get_backing_file(lc);
+ break;
+ case COL_OFFSET:
+ if (loopcxt_get_offset(lc, &x) == 0)
+ xasprintf(&np, "%jd", x);
+ break;
+ case COL_SIZELIMIT:
+ if (loopcxt_get_sizelimit(lc, &x) == 0)
+ xasprintf(&np, "%jd", x);
+ break;
+ case COL_BACK_MAJMIN:
+ {
+ dev_t dev = 0;
+ if (loopcxt_get_backing_devno(lc, &dev) == 0 && dev)
+ xasprintf(&np, "%8u:%-3u", major(dev), minor(dev));
+ break;
+ }
+ case COL_MAJMIN:
+ {
+ struct stat st;
+
+ if (loopcxt_get_device(lc)
+ && stat(loopcxt_get_device(lc), &st) == 0
+ && S_ISBLK(st.st_mode)
+ && major(st.st_rdev) == LOOPDEV_MAJOR)
+ xasprintf(&np, "%3u:%-3u", major(st.st_rdev),
+ minor(st.st_rdev));
+ break;
+ }
+ case COL_BACK_INO:
+ {
+ ino_t ino = 0;
+ if (loopcxt_get_backing_inode(lc, &ino) == 0 && ino)
+ xasprintf(&np, "%ju", ino);
+ break;
+ }
+ case COL_AUTOCLR:
+ p = loopcxt_is_autoclear(lc) ? "1" : "0";
+ break;
+ case COL_RO:
+ p = loopcxt_is_readonly(lc) ? "1" : "0";
+ break;
+ case COL_DIO:
+ p = loopcxt_is_dio(lc) ? "1" : "0";
+ break;
+ case COL_PARTSCAN:
+ p = loopcxt_is_partscan(lc) ? "1" : "0";
+ break;
+ case COL_LOGSEC:
+ if (loopcxt_get_blocksize(lc, &x) == 0)
+ xasprintf(&np, "%jd", x);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+
+ if (p)
+ rc = scols_line_set_data(ln, i, p); /* calls strdup() */
+ else if (np)
+ rc = scols_line_refer_data(ln, i, np); /* only refers */
+
+ if (rc)
+ err(EXIT_FAILURE, _("failed to add output data"));
+ }
+
+ return 0;
+}
+
+static int show_table(struct loopdev_cxt *lc,
+ const char *file,
+ uint64_t offset,
+ int flags)
+{
+ struct stat sbuf, *st = &sbuf;
+ struct libscols_table *tb;
+ struct libscols_line *ln;
+ int rc = 0;
+ size_t i;
+
+ scols_init_debug(0);
+
+ if (!(tb = scols_new_table()))
+ err(EXIT_FAILURE, _("failed to allocate output table"));
+ scols_table_enable_raw(tb, raw);
+ scols_table_enable_json(tb, json);
+ scols_table_enable_noheadings(tb, no_headings);
+
+ if (json)
+ scols_table_set_name(tb, "loopdevices");
+
+ for (i = 0; i < ncolumns; i++) {
+ struct colinfo *ci = get_column_info(i);
+ struct libscols_column *cl;
+
+ cl = scols_table_new_column(tb, ci->name, ci->whint, ci->flags);
+ if (!cl)
+ err(EXIT_FAILURE, _("failed to allocate output column"));
+ if (json)
+ scols_column_set_json_type(cl, ci->json_type);
+ }
+
+ /* only one loopdev requested (already assigned to loopdev_cxt) */
+ if (loopcxt_get_device(lc)) {
+ ln = scols_table_new_line(tb, NULL);
+ if (!ln)
+ err(EXIT_FAILURE, _("failed to allocate output line"));
+ rc = set_scols_data(lc, ln);
+
+ /* list all loopdevs */
+ } else {
+ char *cn_file = NULL;
+
+ rc = loopcxt_init_iterator(lc, LOOPITER_FL_USED);
+ if (rc)
+ goto done;
+ if (!file || stat(file, st))
+ st = NULL;
+
+ while (loopcxt_next(lc) == 0) {
+ if (file) {
+ int used;
+ const char *bf = cn_file ? cn_file : file;
+
+ used = loopcxt_is_used(lc, st, bf, offset, 0, flags);
+ if (!used && !cn_file) {
+ bf = cn_file = canonicalize_path(file);
+ used = loopcxt_is_used(lc, st, bf, offset, 0, flags);
+ }
+ if (!used)
+ continue;
+ }
+
+ ln = scols_table_new_line(tb, NULL);
+ if (!ln)
+ err(EXIT_FAILURE, _("failed to allocate output line"));
+ rc = set_scols_data(lc, ln);
+ if (rc)
+ break;
+ }
+
+ loopcxt_deinit_iterator(lc);
+ free(cn_file);
+ }
+done:
+ if (rc == 0)
+ rc = scols_print_table(tb);
+ scols_unref_table(tb);
+ return rc;
+}
+
+static void __attribute__((__noreturn__)) usage(void)
+{
+ FILE *out = stdout;
+ size_t i;
+
+ fputs(USAGE_HEADER, out);
+
+ fprintf(out,
+ _(" %1$s [options] [<loopdev>]\n"
+ " %1$s [options] -f | <loopdev> <file>\n"),
+ program_invocation_short_name);
+
+ fputs(USAGE_SEPARATOR, out);
+ fputs(_("Set up and control loop devices.\n"), out);
+
+ /* commands */
+ fputs(USAGE_OPTIONS, out);
+ fputs(_(" -a, --all list all used devices\n"), out);
+ fputs(_(" -d, --detach <loopdev>... detach one or more devices\n"), out);
+ fputs(_(" -D, --detach-all detach all used devices\n"), out);
+ fputs(_(" -f, --find find first unused device\n"), out);
+ fputs(_(" -c, --set-capacity <loopdev> resize the device\n"), out);
+ fputs(_(" -j, --associated <file> list all devices associated with <file>\n"), out);
+ fputs(_(" -L, --nooverlap avoid possible conflict between devices\n"), out);
+
+ /* commands options */
+ fputs(USAGE_SEPARATOR, out);
+ fputs(_(" -o, --offset <num> start at offset <num> into file\n"), out);
+ fputs(_(" --sizelimit <num> device is limited to <num> bytes of the file\n"), out);
+ fputs(_(" -b --sector-size <num> set the logical sector size to <num>\n"), out);
+ fputs(_(" -P, --partscan create a partitioned loop device\n"), out);
+ fputs(_(" -r, --read-only set up a read-only loop device\n"), out);
+ fputs(_(" --direct-io[=<on|off>] open backing file with O_DIRECT\n"), out);
+ fputs(_(" --show print device name after setup (with -f)\n"), out);
+ fputs(_(" -v, --verbose verbose mode\n"), out);
+
+ /* output options */
+ fputs(USAGE_SEPARATOR, out);
+ fputs(_(" -J, --json use JSON --list output format\n"), out);
+ fputs(_(" -l, --list list info about all or specified (default)\n"), out);
+ fputs(_(" -n, --noheadings don't print headings for --list output\n"), out);
+ fputs(_(" -O, --output <cols> specify columns to output for --list\n"), out);
+ fputs(_(" --output-all output all columns\n"), out);
+ fputs(_(" --raw use raw --list output format\n"), out);
+
+ fputs(USAGE_SEPARATOR, out);
+ printf(USAGE_HELP_OPTIONS(31));
+
+ fputs(USAGE_COLUMNS, out);
+ for (i = 0; i < ARRAY_SIZE(infos); i++)
+ fprintf(out, " %12s %s\n", infos[i].name, _(infos[i].help));
+
+ printf(USAGE_MAN_TAIL("losetup(8)"));
+
+ exit(EXIT_SUCCESS);
+}
+
+static void warn_size(const char *filename, uint64_t size)
+{
+ struct stat st;
+
+ if (!size) {
+ if (stat(filename, &st) || S_ISBLK(st.st_mode))
+ return;
+ size = st.st_size;
+ }
+
+ if (size < 512)
+ warnx(_("%s: Warning: file is smaller than 512 bytes; the loop device "
+ "may be useless or invisible for system tools."),
+ filename);
+ else if (size % 512)
+ warnx(_("%s: Warning: file does not fit into a 512-byte sector; "
+ "the end of the file will be ignored."),
+ filename);
+}
+
+static int create_loop(struct loopdev_cxt *lc,
+ int nooverlap, int lo_flags, int flags,
+ const char *file, uint64_t offset, uint64_t sizelimit)
+{
+ int hasdev = loopcxt_has_device(lc);
+ int rc = 0;
+
+ /* losetup --find --noverlap file.img */
+ if (!hasdev && nooverlap) {
+ rc = loopcxt_find_overlap(lc, file, offset, sizelimit);
+ switch (rc) {
+ case 0: /* not found */
+ break;
+
+ case 1: /* overlap */
+ loopcxt_deinit(lc);
+ errx(EXIT_FAILURE, _("%s: overlapping loop device exists"), file);
+
+ case 2: /* overlap -- full size and offset match (reuse) */
+ {
+ uint32_t lc_encrypt_type;
+
+ /* Once a loop is initialized RO, there is no
+ * way to change its parameters. */
+ if (loopcxt_is_readonly(lc)
+ && !(lo_flags & LO_FLAGS_READ_ONLY)) {
+ loopcxt_deinit(lc);
+ errx(EXIT_FAILURE, _("%s: overlapping read-only loop device exists"), file);
+ }
+
+ /* This is no more supported, but check to be safe. */
+ if (loopcxt_get_encrypt_type(lc, &lc_encrypt_type) == 0
+ && lc_encrypt_type != LO_CRYPT_NONE) {
+ loopcxt_deinit(lc);
+ errx(EXIT_FAILURE, _("%s: overlapping encrypted loop device exists"), file);
+ }
+
+ lc->info.lo_flags &= ~LO_FLAGS_AUTOCLEAR;
+ if (loopcxt_set_status(lc)) {
+ loopcxt_deinit(lc);
+ errx(EXIT_FAILURE, _("%s: failed to re-use loop device"), file);
+ }
+ return 0; /* success, re-use */
+ }
+ default: /* error */
+ loopcxt_deinit(lc);
+ errx(EXIT_FAILURE, _("failed to inspect loop devices"));
+ return -errno;
+ }
+ }
+
+ if (hasdev && !is_loopdev(loopcxt_get_device(lc)))
+ loopcxt_add_device(lc);
+
+ /* losetup --noverlap /dev/loopN file.img */
+ if (hasdev && nooverlap) {
+ struct loopdev_cxt lc2;
+
+ if (loopcxt_init(&lc2, 0)) {
+ loopcxt_deinit(lc);
+ err(EXIT_FAILURE, _("failed to initialize loopcxt"));
+ }
+ rc = loopcxt_find_overlap(&lc2, file, offset, sizelimit);
+ loopcxt_deinit(&lc2);
+
+ if (rc) {
+ loopcxt_deinit(lc);
+ if (rc > 0)
+ errx(EXIT_FAILURE, _("%s: overlapping loop device exists"), file);
+ err(EXIT_FAILURE, _("%s: failed to check for conflicting loop devices"), file);
+ }
+ }
+
+ /* Create a new device */
+ do {
+ const char *errpre;
+
+ /* Note that loopcxt_{find_unused,set_device}() resets
+ * loopcxt struct.
+ */
+ if (!hasdev && (rc = loopcxt_find_unused(lc))) {
+ warnx(_("cannot find an unused loop device"));
+ break;
+ }
+ if (flags & LOOPDEV_FL_OFFSET)
+ loopcxt_set_offset(lc, offset);
+ if (flags & LOOPDEV_FL_SIZELIMIT)
+ loopcxt_set_sizelimit(lc, sizelimit);
+ if (lo_flags)
+ loopcxt_set_flags(lc, lo_flags);
+ if ((rc = loopcxt_set_backing_file(lc, file))) {
+ warn(_("%s: failed to use backing file"), file);
+ break;
+ }
+ errno = 0;
+ rc = loopcxt_setup_device(lc);
+ if (rc == 0)
+ break; /* success */
+ if (errno == EBUSY && !hasdev)
+ continue;
+
+ /* errors */
+ errpre = hasdev && loopcxt_get_fd(lc) < 0 ?
+ loopcxt_get_device(lc) : file;
+ warn(_("%s: failed to set up loop device"), errpre);
+ break;
+ } while (hasdev == 0);
+
+ return rc;
+}
+
+int main(int argc, char **argv)
+{
+ struct loopdev_cxt lc;
+ int act = 0, flags = 0, no_overlap = 0, c;
+ char *file = NULL;
+ uint64_t offset = 0, sizelimit = 0, blocksize = 0;
+ int res = 0, showdev = 0, lo_flags = 0;
+ char *outarg = NULL;
+ int list = 0;
+ unsigned long use_dio = 0, set_dio = 0, set_blocksize = 0;
+
+ enum {
+ OPT_SIZELIMIT = CHAR_MAX + 1,
+ OPT_SHOW,
+ OPT_RAW,
+ OPT_DIO,
+ OPT_OUTPUT_ALL
+ };
+ static const struct option longopts[] = {
+ { "all", no_argument, NULL, 'a' },
+ { "set-capacity", required_argument, NULL, 'c' },
+ { "detach", required_argument, NULL, 'd' },
+ { "detach-all", no_argument, NULL, 'D' },
+ { "find", no_argument, NULL, 'f' },
+ { "nooverlap", no_argument, NULL, 'L' },
+ { "help", no_argument, NULL, 'h' },
+ { "associated", required_argument, NULL, 'j' },
+ { "json", no_argument, NULL, 'J' },
+ { "list", no_argument, NULL, 'l' },
+ { "sector-size", required_argument, NULL, 'b' },
+ { "noheadings", no_argument, NULL, 'n' },
+ { "offset", required_argument, NULL, 'o' },
+ { "output", required_argument, NULL, 'O' },
+ { "output-all", no_argument, NULL, OPT_OUTPUT_ALL },
+ { "sizelimit", required_argument, NULL, OPT_SIZELIMIT },
+ { "partscan", no_argument, NULL, 'P' },
+ { "read-only", no_argument, NULL, 'r' },
+ { "direct-io", optional_argument, NULL, OPT_DIO },
+ { "raw", no_argument, NULL, OPT_RAW },
+ { "show", no_argument, NULL, OPT_SHOW },
+ { "verbose", no_argument, NULL, 'v' },
+ { "version", no_argument, NULL, 'V' },
+ { NULL, 0, NULL, 0 }
+ };
+
+ static const ul_excl_t excl[] = { /* rows and cols in ASCII order */
+ { 'D','a','c','d','f','j' },
+ { 'D','c','d','f','l' },
+ { 'D','c','d','f','O' },
+ { 'J',OPT_RAW },
+ { 0 }
+ };
+ int excl_st[ARRAY_SIZE(excl)] = UL_EXCL_STATUS_INIT;
+
+ setlocale(LC_ALL, "");
+ bindtextdomain(PACKAGE, LOCALEDIR);
+ textdomain(PACKAGE);
+ atexit(close_stdout);
+
+ if (loopcxt_init(&lc, 0))
+ err(EXIT_FAILURE, _("failed to initialize loopcxt"));
+
+ while ((c = getopt_long(argc, argv, "ab:c:d:Dfhj:JlLno:O:PrvV",
+ longopts, NULL)) != -1) {
+
+ err_exclusive_options(c, longopts, excl, excl_st);
+
+ switch (c) {
+ case 'a':
+ act = A_SHOW;
+ break;
+ case 'b':
+ set_blocksize = 1;
+ blocksize = strtosize_or_err(optarg, _("failed to parse logical block size"));
+ break;
+ case 'c':
+ act = A_SET_CAPACITY;
+ if (!is_loopdev(optarg) ||
+ loopcxt_set_device(&lc, optarg))
+ err(EXIT_FAILURE, _("%s: failed to use device"),
+ optarg);
+ break;
+ case 'r':
+ lo_flags |= LO_FLAGS_READ_ONLY;
+ break;
+ case 'd':
+ act = A_DELETE;
+ if (!is_loopdev(optarg) ||
+ loopcxt_set_device(&lc, optarg))
+ err(EXIT_FAILURE, _("%s: failed to use device"),
+ optarg);
+ break;
+ case 'D':
+ act = A_DELETE_ALL;
+ break;
+ case 'f':
+ act = A_FIND_FREE;
+ break;
+ case 'h':
+ usage();
+ break;
+ case 'J':
+ json = 1;
+ break;
+ case 'j':
+ act = A_SHOW;
+ file = optarg;
+ break;
+ case 'l':
+ list = 1;
+ break;
+ case 'L':
+ no_overlap = 1;
+ break;
+ case 'n':
+ no_headings = 1;
+ break;
+ case OPT_RAW:
+ raw = 1;
+ break;
+ case 'o':
+ offset = strtosize_or_err(optarg, _("failed to parse offset"));
+ flags |= LOOPDEV_FL_OFFSET;
+ break;
+ case 'O':
+ outarg = optarg;
+ list = 1;
+ break;
+ case OPT_OUTPUT_ALL:
+ for (ncolumns = 0; ncolumns < ARRAY_SIZE(infos); ncolumns++)
+ columns[ncolumns] = ncolumns;
+ break;
+ case 'P':
+ lo_flags |= LO_FLAGS_PARTSCAN;
+ break;
+ case OPT_SHOW:
+ showdev = 1;
+ break;
+ case OPT_DIO:
+ use_dio = set_dio = 1;
+ if (optarg)
+ use_dio = parse_switch(optarg, _("argument error"), "on", "off", NULL);
+ break;
+ case 'v':
+ break;
+ case 'V':
+ printf(UTIL_LINUX_VERSION);
+ return EXIT_SUCCESS;
+ case OPT_SIZELIMIT: /* --sizelimit */
+ sizelimit = strtosize_or_err(optarg, _("failed to parse size"));
+ flags |= LOOPDEV_FL_SIZELIMIT;
+ break;
+ default:
+ errtryhelp(EXIT_FAILURE);
+ }
+ }
+
+ ul_path_init_debug();
+ ul_sysfs_init_debug();
+
+ /* default is --list --all */
+ if (argc == 1) {
+ act = A_SHOW;
+ list = 1;
+ }
+
+ if (!act && argc == 2 && (raw || json)) {
+ act = A_SHOW;
+ list = 1;
+ }
+
+ /* default --list output columns */
+ if (list && !ncolumns) {
+ columns[ncolumns++] = COL_NAME;
+ columns[ncolumns++] = COL_SIZELIMIT;
+ columns[ncolumns++] = COL_OFFSET;
+ columns[ncolumns++] = COL_AUTOCLR;
+ columns[ncolumns++] = COL_RO;
+ columns[ncolumns++] = COL_BACK_FILE;
+ columns[ncolumns++] = COL_DIO;
+ columns[ncolumns++] = COL_LOGSEC;
+ }
+
+ if (act == A_FIND_FREE && optind < argc) {
+ /*
+ * losetup -f <backing_file>
+ */
+ act = A_CREATE;
+ file = argv[optind++];
+
+ if (optind < argc)
+ errx(EXIT_FAILURE, _("unexpected arguments"));
+ }
+
+ if (list && !act && optind == argc)
+ /*
+ * losetup --list defaults to --all
+ */
+ act = A_SHOW;
+
+ if (!act && optind + 1 == argc) {
+ /*
+ * losetup [--list] <device>
+ * OR
+ * losetup {--direct-io[=off]|--logical-blocksize=size}... <device>
+ */
+ if (!(set_dio || set_blocksize))
+ act = A_SHOW_ONE;
+ if (set_dio)
+ act = A_SET_DIRECT_IO;
+ if (set_blocksize)
+ act = A_SET_BLOCKSIZE;
+ if (!is_loopdev(argv[optind]) ||
+ loopcxt_set_device(&lc, argv[optind]))
+ err(EXIT_FAILURE, _("%s: failed to use device"),
+ argv[optind]);
+ optind++;
+ }
+ if (!act) {
+ /*
+ * losetup <loopdev> <backing_file>
+ */
+ act = A_CREATE;
+
+ if (optind >= argc)
+ errx(EXIT_FAILURE, _("no loop device specified"));
+ /* don't use is_loopdev() here, the device does not have exist yet */
+ if (loopcxt_set_device(&lc, argv[optind]))
+ err(EXIT_FAILURE, _("%s: failed to use device"),
+ argv[optind]);
+ optind++;
+
+ if (optind >= argc)
+ errx(EXIT_FAILURE, _("no file specified"));
+ file = argv[optind++];
+ }
+
+ if (act != A_CREATE &&
+ (sizelimit || lo_flags || showdev))
+ errx(EXIT_FAILURE,
+ _("the options %s are allowed during loop device setup only"),
+ "--{sizelimit,read-only,show}");
+
+ if ((flags & LOOPDEV_FL_OFFSET) &&
+ act != A_CREATE && (act != A_SHOW || !file))
+ errx(EXIT_FAILURE, _("the option --offset is not allowed in this context"));
+
+ if (outarg && string_add_to_idarray(outarg, columns, ARRAY_SIZE(columns),
+ &ncolumns, column_name_to_id) < 0)
+ return EXIT_FAILURE;
+
+ switch (act) {
+ case A_CREATE:
+ res = create_loop(&lc, no_overlap, lo_flags, flags, file, offset, sizelimit);
+ if (res == 0) {
+ if (showdev)
+ printf("%s\n", loopcxt_get_device(&lc));
+ warn_size(file, sizelimit);
+ if (set_dio || set_blocksize)
+ goto lo_set_post;
+ }
+ break;
+ case A_DELETE:
+ res = delete_loop(&lc);
+ while (optind < argc) {
+ if (!is_loopdev(argv[optind]) ||
+ loopcxt_set_device(&lc, argv[optind]))
+ warn(_("%s: failed to use device"),
+ argv[optind]);
+ optind++;
+ res += delete_loop(&lc);
+ }
+ break;
+ case A_DELETE_ALL:
+ res = delete_all_loops(&lc);
+ break;
+ case A_FIND_FREE:
+ res = loopcxt_find_unused(&lc);
+ if (res) {
+ int errsv = errno;
+
+ if (access(_PATH_DEV_LOOPCTL, F_OK) == 0 &&
+ access(_PATH_DEV_LOOPCTL, W_OK) != 0)
+ ;
+ else
+ errno = errsv;
+
+ warn(_("cannot find an unused loop device"));
+ } else
+ printf("%s\n", loopcxt_get_device(&lc));
+ break;
+ case A_SHOW:
+ if (list)
+ res = show_table(&lc, file, offset, flags);
+ else
+ res = show_all_loops(&lc, file, offset, flags);
+ break;
+ case A_SHOW_ONE:
+ if (list)
+ res = show_table(&lc, NULL, 0, 0);
+ else
+ res = printf_loopdev(&lc);
+ if (res)
+ warn("%s", loopcxt_get_device(&lc));
+ break;
+ case A_SET_CAPACITY:
+ res = loopcxt_set_capacity(&lc);
+ if (res)
+ warn(_("%s: set capacity failed"),
+ loopcxt_get_device(&lc));
+ break;
+ case A_SET_DIRECT_IO:
+ case A_SET_BLOCKSIZE:
+ lo_set_post:
+ if (set_dio) {
+ res = loopcxt_set_dio(&lc, use_dio);
+ if (res)
+ warn(_("%s: set direct io failed"),
+ loopcxt_get_device(&lc));
+ }
+ if (set_blocksize) {
+ res = loopcxt_set_blocksize(&lc, blocksize);
+ if (res)
+ warn(_("%s: set logical block size failed"),
+ loopcxt_get_device(&lc));
+ }
+ break;
+ default:
+ warnx(_("bad usage"));
+ errtryhelp(EXIT_FAILURE);
+ break;
+ }
+
+ loopcxt_deinit(&lc);
+ return res ? EXIT_FAILURE : EXIT_SUCCESS;
+}
+
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-21 20:38:22 +0000