The command lists all disks (real and virtual) as well as disk
partitions. For each disk the list of slave disks is also listed and
/dev path is used as a handle so it can be matched with "name" filed of
field
other returned disk entries. For disk partitions the "slave" list is
populated with the the parent device for easier tracking of hierarchy.
Example output:
{
"return": [
...
{
"name": "/dev/dm-0",
"partition": false,
"slaves": [
"/dev/sda2"
],
"alias": "luks-7062202e-5b9b-433e-81e8-6628c40da9f7"
},
{
"name": "/dev/sda2",
"partition": true,
"slaves": [
"/dev/sda"
]
},
{
"name": "/dev/sda",
"partition": false,
"address": {
"serial": "SAMSUNG_MZ7LN512HCHP-000L1_S1ZKNXAG822493",
"bus-type": "sata",
...
"dev": "/dev/sda",
"target": 0
},
"slaves": []
},
...
]
}
Signed-off-by: Tomáš Golembiovský <tgolembi@redhat.com>
---
qga/commands-posix.c | 247 +++++++++++++++++++++++++++++++++++++++++--
1 file changed, 240 insertions(+), 7 deletions(-)
diff --git a/qga/commands-posix.c b/qga/commands-posix.c
index f99731af51..3babc25c09 100644
--- a/qga/commands-posix.c
+++ b/qga/commands-posix.c
@@ -62,6 +62,9 @@ extern char **environ;
#endif
#endif
+G_DEFINE_AUTOPTR_CLEANUP_FUNC(GuestFilesystemInfo,
+ qapi_free_GuestFilesystemInfo)
+
This will now conflict with qapi-gen generated headers.
static void ga_wait_child(pid_t pid, int *status, Error **errp)
{
pid_t rpid;
@@ -1150,6 +1153,21 @@ static void build_guest_fsinfo_for_virtual_device(char const *syspath,
closedir(dir);
}
+static bool is_disk_virtual(const char *devpath, Error **errp)
+{
+ g_autofree char *syspath = realpath(devpath, NULL);
+
+ if (!syspath) {
+ error_setg_errno(errp, errno, "realpath(\"%s\")", devpath);
+ return false;
+ }
+ if (strstr(syspath, "/devices/virtual/block/")) {
+ return true;
+ } else {
+ return false;
+ }
simply to "return strstr(syspath, "/devices/virtual/block/") != NULL;" ? (Or strstr(syspath, "/devices/virtual/block/") ? true : false )
+}
+
/* Dispatch to functions for virtual/real device */
static void build_guest_fsinfo_for_device(char const *devpath,
GuestFilesystemInfo *fs,
@@ -1168,6 +1186,7 @@ static void build_guest_fsinfo_for_device(char const *devpath,
g_debug(" parse sysfs path '%s'", syspath);
+ /* TODO: use is_disk_virtual() */
just do it, no?
if (strstr(syspath, "/devices/virtual/block/")) {
build_guest_fsinfo_for_virtual_device(syspath, fs, errp);
} else {
@@ -1177,6 +1196,225 @@ static void build_guest_fsinfo_for_device(char const *devpath,
free(syspath);
}
+#ifdef CONFIG_LIBUDEV
+
+/*
+ * Wrapper around build_guest_fsinfo_for_device() for getting just
+ * the disk address.
+ */
+static GuestDiskAddress *get_disk_address(const char *syspath, Error **errp)
+{
+ g_autoptr(GuestFilesystemInfo) fs = NULL;
+
+ fs = g_new0(GuestFilesystemInfo, 1);
Heap allocation / auto wasn't really necessary here, but ok.
+ build_guest_fsinfo_for_device(syspath, fs, errp);
+ if (fs->disk != NULL) {
+ return g_steal_pointer(&fs->disk->value);
+ }
+ return NULL;
Could also be a onliner, but perhaps less readable.
+}
+
+static char *get_alias_for_syspath(const char *syspath)
+{
+ struct udev *udev = NULL;
+ struct udev_device *udevice = NULL;
+ char *ret = NULL;
+
+ udev = udev_new();
I would have g_return_val_if_fail(udev != NULL, NULL); here as,
+ udevice = udev_device_new_from_syspath(udev, syspath);
udev_device_new_from_syspath() might crash otherwise.
+ if (udev == NULL || udevice == NULL) {
+ g_debug("failed to query udev");
+ } else {
+ const char *alias = udev_device_get_property_value(
+ udevice, "DM_NAME");
+ if (alias != NULL && *alias != 0) {
+ ret = g_strdup(alias);
g_strdup() works fine with NULL. Is there "" empty aliases? Why not report them too?
+ }
+ }
+
+ udev_unref(udev);
+ udev_device_unref(udevice);
+ return ret;
+}
+
+static char *get_device_for_syspath(const char *syspath)
+{
+ struct udev *udev = NULL;
+ struct udev_device *udevice = NULL;
+ char *ret = NULL;
+
+ udev = udev_new();
+ udevice = udev_device_new_from_syspath(udev, syspath);
+ if (udev == NULL || udevice == NULL) {
Same as above
+ g_debug("failed to query udev");
+ } else {
+ ret = g_strdup(udev_device_get_devnode(udevice));
+ }
+ udev_unref(udev);
+ udev_device_unref(udevice);
+ return ret;
+}
+
+GuestDiskInfoList *qmp_guest_get_disks(Error **errp)
+{
+ GuestDiskInfoList *item, *ret = NULL;
+ GuestDiskInfo *disk, *partition;
+ DIR *dp = NULL;
+ struct dirent *de = NULL;
+
+ g_debug("listing /sys/block directory");
+ dp = opendir("/sys/block");
+ if (dp == NULL) {
+ error_setg_errno(errp, errno, "Can't open directory \"/sys/block\"");
+ return NULL;
+ }
+ while ((de = readdir(dp)) != NULL) {
+ g_autofree char *disk_dir = NULL, *line = NULL,
+ *size_dir = NULL, *slaves_dir = NULL;
+ struct dirent *de_disk, *de_slaves;
+ DIR *dp_disk = NULL, *dp_slaves = NULL;
+ FILE *fp = NULL;
+ size_t n = 0;
+ Error *local_err = NULL;
+ if (de->d_type != DT_LNK) {
+ g_debug(" skipping entry: %s", de->d_name);
+ continue;
+ }
+
+ /* Check size and skip zero-sized disks */
+ g_debug(" checking disk size");
+ size_dir = g_strdup_printf("/sys/block/%s/size", de->d_name);
+ fp = fopen(size_dir, "r");
+ if (!fp) {
+ g_debug(" failed to read disk size");
+ continue;
+ }
+ if (getline(&line, &n, fp) == -1) {
+ g_debug(" failed to read disk size");
line: getline(3) "This buffer should be freed by the user program even if getline() failed."
+ fclose(fp);
+ continue;
+ }
+ fclose(fp);
+ if (strcmp(line, "0\n") == 0) {
It would be slightly better to defend against NULL crash here, with g_strcmp0()
+ g_debug(" skipping zero-sized disk");
+ continue;
+ }
+
line is never freed?
+ g_debug(" adding %s", de->d_name);
+ disk_dir = g_strdup_printf("/sys/block/%s", de->d_name);
+ disk = g_new0(GuestDiskInfo, 1);
+ disk->name = get_device_for_syspath(disk_dir);
+ disk->partition = false;
+ disk->alias = get_alias_for_syspath(disk_dir);
+ if (disk->alias != NULL) {
+ disk->has_alias = true;
+ }
Could be a single line too
+ item = g_new0(GuestDiskInfoList, 1);
+ item->value = disk;
+ item->next = ret;
+ ret = item;
+
+ /* Get address for non-virtual devices */
+ bool is_virtual = is_disk_virtual(disk_dir, &local_err);
+ if (local_err != NULL) {
+ g_debug(" failed to check disk path, ignoring error: %s",
+ error_get_pretty(local_err));
+ error_free(local_err);
+ local_err = NULL;
+ /* Don't try to get the address */
+ is_virtual = true;
+ }
+ if (!is_virtual) {
+ disk->address = get_disk_address(disk_dir, &local_err);
+ if (local_err != NULL) {
+ g_debug(" failed to get device info, ignoring error: %s",
+ error_get_pretty(local_err));
+ error_free(local_err);
+ local_err = NULL;
+ } else if (disk->address != NULL) {
+ disk->has_address = true;
+ }
+ }
+
+ /* List slave disks */
+ slaves_dir = g_strdup_printf("%s/slaves", disk_dir);
+ g_debug(" listing entries in: %s", slaves_dir);
+ dp_slaves = opendir(slaves_dir);
+ while ((de_slaves = readdir(dp_slaves)) != NULL) {
+ g_autofree char *slave_dir = NULL;
+ char *slave_dev;
+ strList *slave_item = NULL;
+
+ if ((strcmp(".", de_slaves->d_name) == 0) ||
+ (strcmp("..", de_slaves->d_name) == 0)) {
+ continue;
+ }
+
+ /* Add slave disks */
+ slave_dir = g_strdup_printf("%s/%s",
+ slaves_dir, de_slaves->d_name);
+ slave_dev = get_device_for_syspath(slave_dir);
+ if (slave_dev != NULL) {
+ g_debug(" adding slave device: %s", slave_dev);
+ slave_item = g_new0(strList, 1);
+ slave_item->value = slave_dev;
+ slave_item->next = disk->slaves;
+ disk->slaves = slave_item;
+ }
+ }
+ closedir(dp_slaves);
+
+ /*
+ * Detect partitions subdirectory name is "<parent><number>" or
+ * "<parent>p<number>"
+ */
+ dp_disk = opendir(disk_dir);
+ while ((de_disk = readdir(dp_disk)) != NULL) {
+ size_t len;
+ g_autofree char *partition_dir = NULL;
+
+ if (!(de_disk->d_type & DT_DIR)) {
+ continue;
+ }
+
+ len = strlen(de->d_name);
+ if (!(strncmp(de->d_name, de_disk->d_name, len) == 0 &&
+ ((*(de_disk->d_name + len) == 'p' &&
+ isdigit(*(de_disk->d_name + len + 1))) ||
+ isdigit(*(de_disk->d_name + len))))) {
+ continue;
+ }
+
+ partition_dir = g_strdup_printf("%s/%s",
+ disk_dir, de_disk->d_name);
+ partition = g_new0(GuestDiskInfo, 1);
+ partition->name = get_device_for_syspath(partition_dir);
+ partition->partition = true;
+ /* Add parent disk as slave for easier tracking of hierarchy */
+ partition->slaves = g_new0(strList, 1);
+ partition->slaves->value = g_strdup(disk->name);
+
+ item = g_new0(GuestDiskInfoList, 1);
+ item->value = partition;
+ item->next = ret;
+ ret = item;
+
+ }
+ closedir(dp_disk);
+ }
+ return ret;
+}
+
+#else
+
+GuestDiskInfoList *qmp_guest_get_disks(Error **errp)
+{
+ error_setg(errp, QERR_UNSUPPORTED);
+ return NULL;
+}
+
+#endif
+
/* Return a list of the disk device(s)' info which @mount lies on */
static GuestFilesystemInfo *build_guest_fsinfo(struct FsMount *mount,
Error **errp)
@@ -2809,7 +3047,8 @@ GList *ga_command_blacklist_init(GList *blacklist)
const char *list[] = {
"guest-get-fsinfo", "guest-fsfreeze-status",
"guest-fsfreeze-freeze", "guest-fsfreeze-freeze-list",
- "guest-fsfreeze-thaw", "guest-get-fsinfo", NULL};
+ "guest-fsfreeze-thaw", "guest-get-fsinfo",
+ "guest-get-disks", NULL};
char **p = (char **)list;
while (*p) {
@@ -3042,9 +3281,3 @@ GuestOSInfo *qmp_guest_get_osinfo(Error **errp)
return info;
}
-
-GuestDiskInfoList *qmp_guest_get_disks(Error **errp)
-{
- error_setg(errp, QERR_UNSUPPORTED);
- return NULL;
-}
--
2.25.0