From a60cc5c2eeaad7ea5ea0c4a74cc4af5e2dc3f6c2 Mon Sep 17 00:00:00 2001
From: Ruediger Meier <ruediger.meier@ga-group.nl>
Date: Tue, 4 Apr 2017 16:29:58 +0200
Subject: [PATCH]
util-linux-losetup-Add-support-for-setting-logical-blocksize.patch
Signed-off-by: Ruediger Meier <ruediger.meier@ga-group.nl>
---
include/loopdev.h | 5 ++++-
lib/loopdev.c | 20 ++++++++++++++++++++
sys-utils/losetup.c | 19 +++++++++++++++----
3 files changed, 39 insertions(+), 5 deletions(-)
diff --git a/include/loopdev.h b/include/loopdev.h
index 953d2db..7c783bf 100644
--- a/include/loopdev.h
+++ b/include/loopdev.h
@@ -41,6 +41,7 @@ enum {
LO_FLAGS_AUTOCLEAR = 4, /* kernel >= 2.6.25 */
LO_FLAGS_PARTSCAN = 8, /* kernel >= 3.2 */
LO_FLAGS_DIRECT_IO = 16, /* kernel >= 4.2 */
+ LO_FLAGS_BLOCKSIZE = 32, /* Tentative */
};
#define LO_NAME_SIZE 64
@@ -120,7 +121,8 @@ enum {
LOOPDEV_FL_NOIOCTL = (1 << 6),
LOOPDEV_FL_DEVSUBDIR = (1 << 7),
LOOPDEV_FL_CONTROL = (1 << 8), /* system with /dev/loop-control */
- LOOPDEV_FL_SIZELIMIT = (1 << 9)
+ LOOPDEV_FL_SIZELIMIT = (1 << 9),
+ LOOPDEV_FL_BLOCKSIZE = (1 << 10)
};
/*
@@ -173,6 +175,7 @@ int loopcxt_set_offset(struct loopdev_cxt *lc, uint64_t offset);
int loopcxt_set_sizelimit(struct loopdev_cxt *lc, uint64_t sizelimit);
int loopcxt_set_flags(struct loopdev_cxt *lc, uint32_t flags);
int loopcxt_set_backing_file(struct loopdev_cxt *lc, const char *filename);
+int loopcxt_set_blocksize(struct loopdev_cxt *lc, uint64_t blocksize);
extern char *loopcxt_get_backing_file(struct loopdev_cxt *lc);
extern int loopcxt_get_backing_devno(struct loopdev_cxt *lc, dev_t *devno);
diff --git a/lib/loopdev.c b/lib/loopdev.c
index fd4f166..b85e2ce 100644
--- a/lib/loopdev.c
+++ b/lib/loopdev.c
@@ -1115,6 +1115,26 @@ int loopcxt_set_backing_file(struct loopdev_cxt *lc, const char *filename)
}
/*
+ * @lc: context
+ * @blocksize: logical blocksize for the device
+ *
+ * The setting is removed by loopcxt_set_device() loopcxt_next()!
+ *
+ * Returns: 0 on success, <0 on error.
+ */
+int loopcxt_set_blocksize(struct loopdev_cxt *lc, uint64_t blocksize)
+{
+ if (!lc)
+ return -EINVAL;
+
+ lc->info.lo_init[0] = blocksize;
+ lc->info.lo_flags |= LO_FLAGS_BLOCKSIZE;
+
+ DBG(CXT, ul_debugobj(lc, "set blocksize=%llu", (long long unsigned int)lc->info.lo_init[0]));
+ return 0;
+}
+
+/*
* In kernels prior to v3.9, if the offset or sizelimit options
* are used, the block device's size won't be synced automatically.
* blockdev --getsize64 and filesystems will use the backing
diff --git a/sys-utils/losetup.c b/sys-utils/losetup.c
index 2218d3b..d8f1bfa 100644
--- a/sys-utils/losetup.c
+++ b/sys-utils/losetup.c
@@ -399,6 +399,7 @@ static void usage(FILE *out)
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(_(" --logical-blocksize <size> set the logical block size to <size>\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);
@@ -448,7 +449,8 @@ static void warn_size(const char *filename, uint64_t size)
static int create_loop(struct loopdev_cxt *lc,
int nooverlap, int lo_flags, int flags,
- const char *file, uint64_t offset, uint64_t sizelimit)
+ const char *file, uint64_t offset, uint64_t sizelimit,
+ uint64_t blocksize)
{
int hasdev = loopcxt_has_device(lc);
int rc = 0;
@@ -534,6 +536,8 @@ static int create_loop(struct loopdev_cxt *lc,
loopcxt_set_offset(lc, offset);
if (flags & LOOPDEV_FL_SIZELIMIT)
loopcxt_set_sizelimit(lc, sizelimit);
+ if (flags & LOOPDEV_FL_BLOCKSIZE)
+ loopcxt_set_blocksize(lc, blocksize);
if (lo_flags)
loopcxt_set_flags(lc, lo_flags);
if ((rc = loopcxt_set_backing_file(lc, file))) {
@@ -562,7 +566,7 @@ 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;
+ uint64_t offset = 0, sizelimit = 0, blocksize = 0;
int res = 0, showdev = 0, lo_flags = 0;
char *outarg = NULL;
int list = 0;
@@ -572,7 +576,8 @@ int main(int argc, char **argv)
OPT_SIZELIMIT = CHAR_MAX + 1,
OPT_SHOW,
OPT_RAW,
- OPT_DIO
+ OPT_DIO,
+ OPT_BLOCKSIZE,
};
static const struct option longopts[] = {
{ "all", no_argument, NULL, 'a' },
@@ -585,6 +590,7 @@ int main(int argc, char **argv)
{ "associated", required_argument, NULL, 'j' },
{ "json", no_argument, NULL, 'J' },
{ "list", no_argument, NULL, 'l' },
+ { "logical-blocksize", required_argument, NULL, OPT_BLOCKSIZE },
{ "noheadings", no_argument, NULL, 'n' },
{ "offset", required_argument, NULL, 'o' },
{ "output", required_argument, NULL, 'O' },
@@ -658,6 +664,10 @@ int main(int argc, char **argv)
act = A_SHOW;
file = optarg;
break;
+ case OPT_BLOCKSIZE:
+ blocksize = strtosize_or_err(optarg, _("failed to parse logical block size"));
+ flags |= LOOPDEV_FL_BLOCKSIZE;
+ break;
case 'l':
list = 1;
break;
@@ -790,7 +800,8 @@ int main(int argc, char **argv)
switch (act) {
case A_CREATE:
- res = create_loop(&lc, no_overlap, lo_flags, flags, file, offset, sizelimit);
+ res = create_loop(&lc, no_overlap, lo_flags, flags, file, offset,
+ sizelimit, blocksize);
if (res == 0) {
if (showdev)
printf("%s\n", loopcxt_get_device(&lc));
--
1.8.5.6