Here's the patch for adding /dev/mapper support to libparted.
ioctl() calls are not supported by /dev/mapper devices. A userspace
communication layer was created to fill the gap:
http://sources.redhat.com/dm/
The library that comes out of the device-mapper package is libdevmapper.
We use this in parted to read/write on these devices.
This patch is against parted trunk in subversion, but applies to
1.8.0rc1. By default, libdevmapper support is disabled, so apply the
patch and run:
./autogen.sh
./configure --enable-device-mapper
If this solves the problem(s) you've been running in to with /dev/mapper
reading and writing, I'd like to include it in 1.8.0rc2. You will need
libdevmapper installed since enabling this feature links libparted with
libdevmapper.
--
David Cantrell
Red Hat / Westford, MA
Index: include/parted/device.h
===================================================================
--- include/parted/device.h (revision 842)
+++ include/parted/device.h (working copy)
@@ -46,6 +46,10 @@
PED_DEVICE_DASD = 9,
PED_DEVICE_VIODASD = 10,
PED_DEVICE_SX8 = 11
+#ifdef ENABLE_DEVICE_MAPPER
+ ,
+ PED_DEVICE_DM = 12
+#endif
} PedDeviceType;
typedef struct _PedDevice PedDevice;
Index: AUTHORS
===================================================================
--- AUTHORS (revision 845)
+++ AUTHORS (working copy)
@@ -211,6 +211,7 @@
Peter Jones <[EMAIL PROTECTED]>
* Add ped_exception_get_handler()
+ * /dev/mapper read/write support on Linux (via libdevmapper)
Darren Lavender <[EMAIL PROTECTED]>
* Fix SIGSEGV in parted 1.6.19 and assertion error in 1.7.0
Index: configure.ac
===================================================================
--- configure.ac (revision 842)
+++ configure.ac (working copy)
@@ -66,6 +66,14 @@
AC_DEFINE(ENABLE_MTRACE, 1, [Mtrace malloc() debugging])
fi
+AC_ARG_ENABLE(device-mapper,
+ [ --enable-device-mapper enable device mapper support [default=no]], ,
+ enable_device_mapper=no
+)
+if test "$enable_device_mapper" = yes; then
+ AC_DEFINE(ENABLE_DEVICE_MAPPER, 1, [device mapper (libdevmapper) support])
+fi
+
AC_ARG_ENABLE(discover-only,
[ --enable-discover-only support only reading/probing [default=no]], ,
enable_discover_only=no
@@ -228,6 +236,19 @@
)
AC_SUBST(UUID_LIBS)
+dnl Check for libdevmapper
+DM_LIBS=""
+if test "$enable_device_mapper" = yes; then
+ AC_CHECK_LIB(devmapper, dm_task_create,
+ DM_LIBS="-ldevmapper -lselinux -lsepol",
+ AC_MSG_ERROR(
+ [libdevmapper not found! Try using --disable-device-mapper]
+ )
+ exit
+ )
+fi
+AC_SUBST(DM_LIBS)
+
dnl Check for libreiserfs
REISER_LIBS=""
if test "$enable_dynamic_loading" = no -a "$enable_discover_only" = no; then
@@ -321,7 +342,7 @@
systems. It is a standard part of a GNU/Hurd system.
)
exit,
- $OS_LIBS $UUID_LIBS $LIBS
+ $OS_LIBS $UUID_LIBS $DM_LIBS $LIBS
)
LIBS="$OLD_LIBS"
fi
Index: libparted/Makefile.am
===================================================================
--- libparted/Makefile.am (revision 842)
+++ libparted/Makefile.am (working copy)
@@ -32,6 +32,7 @@
libparted_la_LIBADD = @OS_LIBS@ \
@DL_LIBS@ \
+ @DM_LIBS@ \
fs/libfs.la \
labels/liblabels.la
Index: libparted/arch/linux.c
===================================================================
--- libparted/arch/linux.c (revision 842)
+++ libparted/arch/linux.c (working copy)
@@ -43,6 +43,9 @@
#include <sys/types.h>
#include <sys/utsname.h> /* for uname() */
#include <scsi/scsi.h>
+#ifdef ENABLE_DEVICE_MAPPER
+#include <libdevmapper.h>
+#endif
#include "blkpg.h"
@@ -305,6 +308,100 @@
}
static int
+readFD (int fd, char **buf)
+{
+ char* p;
+ size_t size = 16384;
+ int s, filesize;
+
+ *buf = calloc (16384, sizeof (char));
+ if (*buf == 0) {
+ return -1;
+ }
+
+ filesize = 0;
+ do {
+ p = &(*buf) [filesize];
+ s = read (fd, p, 16384);
+ if (s < 0)
+ break;
+ filesize += s;
+ /* only exit for empty reads */
+ if (s == 0)
+ break;
+ size += s;
+ *buf = realloc (*buf, size);
+ } while (1);
+
+ if (filesize == 0 && s < 0) {
+ free (*buf);
+ *buf = NULL;
+ return -1;
+ }
+
+ return filesize;
+}
+
+static int
+_is_dm_major (int major)
+{
+ int fd;
+ char* buf = NULL;
+ char* line;
+ char* end;
+ int bd = 0;
+ int rc = 0;
+ char c;
+
+ fd = open ("/proc/devices", O_RDONLY);
+ if (fd < 0)
+ return 0;
+
+ if (readFD(fd, &buf) < 0) {
+ close(fd);
+ return 0;
+ }
+
+ line = buf;
+ end = strchr(line, '\n');
+ while (end && *end) {
+ char *name;
+ int maj;
+
+ c = *end;
+ *end = '\0';
+
+ if (!bd) {
+ if (!strncmp(line, "Block devices:", 14))
+ bd = 1;
+ goto next;
+ }
+
+ name = strrchr(line, ' ');
+ if (!name || !*name || strcmp(name+1, "device-mapper"))
+ goto next;
+
+ maj = strtol(line, &name, 10);
+ if (maj == major) {
+ free(buf);
+ close(fd);
+ return 1;
+ }
+
+next:
+ *end = c;
+ line = end+1;
+ if (line && *line) {
+ end = strchr(line, '\n');
+ } else
+ end = line;
+ }
+ free(buf);
+ close(fd);
+ return 0;
+}
+
+static int
_device_stat (PedDevice* dev, struct stat * dev_stat)
{
PED_ASSERT (dev != NULL, return 0);
@@ -365,6 +462,8 @@
dev->type = PED_DEVICE_CPQARRAY;
} else if (dev_major == UBD_MAJOR && (dev_minor % 0x10 == 0)) {
dev->type = PED_DEVICE_UBD;
+ } else if (_is_dm_major(dev_major)) {
+ dev->type = PED_DEVICE_DM;
} else {
dev->type = PED_DEVICE_UNKNOWN;
}
@@ -1052,6 +1151,11 @@
goto error_free_arch_specific;
break;
+ case PED_DEVICE_DM:
+ if (!init_generic (dev, _("Linux device-mapper")))
+ goto error_free_arch_specific;
+ break;
+
case PED_DEVICE_UNKNOWN:
if (!init_generic (dev, _("Unknown")))
goto error_free_arch_specific;
@@ -1802,6 +1906,7 @@
} else if (dev->type == PED_DEVICE_DAC960
|| dev->type == PED_DEVICE_CPQARRAY
|| dev->type == PED_DEVICE_ATARAID
+ || dev->type == PED_DEVICE_DM
|| isdigit (dev->path[path_len - 1]))
snprintf (result, result_len, "%sp%d", dev->path, num);
else
@@ -2015,6 +2120,237 @@
}
static int
+_dm_remove_map(int major, int minor)
+{
+ struct dm_task *task = NULL;
+ int rc;
+
+ task = dm_task_create(DM_DEVICE_REMOVE);
+ if (!task)
+ return 1;
+
+ dm_task_set_major (task, major);
+ dm_task_set_minor (task, minor);
+
+ rc = dm_task_run(task);
+ dm_task_update_nodes();
+ dm_task_destroy(task);
+ if (rc < 0)
+ return 1;
+
+ return 0;
+}
+
+static int
+_dm_remove_map_name(char *name)
+{
+ struct dm_task *task = NULL;
+ int rc;
+
+ task = dm_task_create(DM_DEVICE_REMOVE);
+ if (!task)
+ return 1;
+
+ dm_task_set_name (task, name);
+
+ rc = dm_task_run(task);
+ dm_task_update_nodes();
+ dm_task_destroy(task);
+ if (rc < 0)
+ return 1;
+
+ return 0;
+}
+
+static int
+_dm_is_part (struct dm_info *this, char *name)
+{
+ struct dm_task* task = NULL;
+ struct dm_info* info = alloca(sizeof *info);
+ struct dm_deps* deps = NULL;
+ int rc = 0;
+ unsigned int i;
+
+ task = dm_task_create(DM_DEVICE_DEPS);
+ if (!task)
+ return 0;
+
+ dm_task_set_name(task, name);
+ rc = dm_task_run(task);
+ if (rc < 0) {
+ rc = 0;
+ goto err;
+ }
+ rc = 0;
+
+ memset(info, '\0', sizeof *info);
+ dm_task_get_info(task, info);
+ if (!info->exists)
+ goto err;
+
+ deps = dm_task_get_deps(task);
+ if (!deps)
+ goto err;
+
+ rc = 0;
+ for (i = 0; i < deps->count; i++) {
+ unsigned int ma = major(deps->device[i]),
+ mi = minor(deps->device[i]);
+
+ if (ma == this->major && mi == this->minor)
+ rc = 1;
+ }
+
+err:
+ dm_task_destroy(task);
+ return rc;
+}
+
+static int
+_dm_remove_parts (PedDevice* dev)
+{
+ struct stat dev_stat;
+ struct dm_task* task = NULL;
+ struct dm_info* info = alloca(sizeof *info);
+ struct dm_names* names = NULL;
+ unsigned int next = 0;
+ int i;
+ int rc;
+
+ if (!_device_stat (dev, &dev_stat))
+ goto err;
+
+ task = dm_task_create(DM_DEVICE_LIST);
+ if (!task)
+ goto err;
+
+ dm_task_set_major (task, major (dev_stat.st_rdev));
+ dm_task_set_minor (task, minor (dev_stat.st_rdev));
+
+ rc = dm_task_run(task);
+ if (rc < 0)
+ goto err;
+
+ memset(info, '\0', sizeof *info);
+ dm_task_get_info(task, info);
+ if (!info->exists)
+ goto err;
+
+ names = dm_task_get_names(task);
+ if (!names)
+ goto err;
+
+ rc = 0;
+ do {
+ names = (void *)names + next;
+
+ if (_dm_is_part(info, names->name))
+ rc += _dm_remove_map_name(names->name);
+
+ next = names->next;
+ } while (next);
+
+ dm_task_update_nodes();
+ dm_task_destroy(task);
+ task = NULL;
+
+ if (!rc)
+ return 1;
+err:
+ if (task)
+ dm_task_destroy(task);
+ ped_exception_throw (PED_EXCEPTION_WARNING, PED_EXCEPTION_IGNORE,
+ _("parted was unable to re-read the partition "
+ "table on %s (%s). This means Linux won't know "
+ "anything about the modifications you made. "),
+ dev->path, strerror (errno));
+ return 0;
+}
+
+static int
+_dm_add_partition (PedDisk* disk, PedPartition* part)
+{
+ struct dm_task* task;
+ struct stat dev_stat;
+ int rc;
+ char* vol_name = NULL;
+ char* dev_name = NULL;
+ char* params = NULL;
+
+ dev_name = _device_get_part_path (disk->dev, part->num);
+ if (!dev_name)
+ return 0;
+
+ vol_name = strrchr (dev_name, '/');
+ if (vol_name && *vol_name && *(++vol_name))
+ vol_name = strdup (vol_name);
+ else
+ vol_name = strdup (dev_name);
+ if (!vol_name)
+ return 0;
+
+ if (!_device_stat (disk->dev, &dev_stat))
+ goto err;
+
+ asprintf (¶ms, "%d:%d %lu", major (dev_stat.st_rdev),
+ minor (dev_stat.st_rdev),
+ part->geom.start);
+ if (!params)
+ goto err;
+
+ task = dm_task_create (DM_DEVICE_CREATE);
+ if (!task)
+ goto err;
+
+ dm_task_set_name (task, vol_name);
+ dm_task_add_target (task, 0, part->geom.length,
+ "linear", params);
+ rc = dm_task_run(task);
+ if (rc >= 0) {
+ //printf("0 %ld linear %s\n", part->geom.length, params);
+ dm_task_update_nodes();
+ dm_task_destroy(task);
+ free(params);
+ free(vol_name);
+ return 1;
+ } else {
+ _dm_remove_map_name(vol_name);
+ }
+err:
+ dm_task_update_nodes();
+ if (task)
+ dm_task_destroy (task);
+ if (params)
+ free (params);
+ free (vol_name);
+ return 0;
+}
+
+static int
+_dm_reread_part_table (PedDisk* disk)
+{
+ int rc = 1;
+ int last = PED_MAX (ped_disk_get_last_partition_num (disk), 16);
+ int i;
+
+ sync();
+ if (!_dm_remove_parts(disk->dev))
+ rc = 0;
+
+ for (i = 1; i <= last; i++) {
+ PedPartition* part;
+
+ part = ped_disk_get_partition (disk, i);
+ if (!part)
+ continue;
+
+ if (!_dm_add_partition (disk, part))
+ rc = 0;
+ }
+ return rc;
+}
+
+static int
_kernel_reread_part_table (PedDevice* dev)
{
LinuxSpecific* arch_specific = LINUX_SPECIFIC (dev);
@@ -2057,7 +2393,9 @@
static int
linux_disk_commit (PedDisk* disk)
{
- if (disk->dev->type != PED_DEVICE_FILE) {
+ if (disk->dev->type == PED_DEVICE_DM) {
+ return _dm_reread_part_table (disk);
+ } else if (disk->dev->type != PED_DEVICE_FILE) {
/* The ioctl() command BLKPG_ADD_PARTITION does not notify
* the devfs system; consequently, /proc/partitions will not
* be up to date, and the proper links in /dev are not
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