libdm-deptree.c

Linux Device Mapper Source Code

			    size_t paramsize, int *pos)
{
	struct seg_area *area;
	char devbuf[10];
	int tw;
	const char *prefix = "";

	list_iterate_items(area, &seg->areas) {
		if (!_build_dev_string(devbuf, sizeof(devbuf), area->dev_node))
			return_0;

		if ((tw = _dm_snprintf(params + *pos, paramsize - *pos, "%s%s %" PRIu64,
					prefix, devbuf, area->offset)) < 0) {
                        stack;	/* Out of space */
                        return -1;
                }

		prefix = " ";
		*pos += tw;
	}

	return 1;
}

static int _emit_segment_line(struct dm_task *dmt, struct load_segment *seg, uint64_t *seg_start, char *params, size_t paramsize)
{
	unsigned log_parm_count;
        int pos = 0;
	int tw;
        int r;
	char originbuf[10], cowbuf[10], logbuf[10];
	const char *logtype;

	switch(seg->type) {
	case SEG_ERROR:
	case SEG_ZERO:
		params[0] = '\0';
	case SEG_LINEAR:
		break;
	case SEG_MIRRORED:
		log_parm_count = 1;	/* Region size */
		log_parm_count += hweight32(seg->flags);	/* [no]sync, block_on_error etc. */

		if (seg->flags & DM_CORELOG)
			log_parm_count--;   /* DM_CORELOG does not count in the param list */

		if (seg->clustered) {
			if (seg->uuid)
				log_parm_count++;
			if ((tw = _dm_snprintf(params + pos, paramsize - pos, "clustered_")) < 0) {
                        	stack;	/* Out of space */
                        	return -1;
                	}
			pos += tw;
		}

		if (!seg->log)
			logtype = "core";
		else {
			logtype = "disk";
			log_parm_count++;
			if (!_build_dev_string(logbuf, sizeof(logbuf), seg->log))
				return_0;
		}

		if ((tw = _dm_snprintf(params + pos, paramsize - pos, "%s %u ", logtype, log_parm_count)) < 0) {
                        stack;	/* Out of space */
                        return -1;
                }
		pos += tw;

		if (seg->log) {
			if ((tw = _dm_snprintf(params + pos, paramsize - pos, "%s ", logbuf)) < 0) {
                        	stack;	/* Out of space */
                        	return -1;
                	}
			pos += tw;
		}

		if ((tw = _dm_snprintf(params + pos, paramsize - pos, "%u ", seg->region_size)) < 0) {
                       	stack; /* Out of space */
                       	return -1;
               	}
		pos += tw;

		if (seg->clustered && seg->uuid) {
			if ((tw = _dm_snprintf(params + pos, paramsize - pos, "%s ", seg->uuid)) < 0) {
				stack;  /* Out of space */
				return -1;
			}
			pos += tw;
		}

		if ((seg->flags & DM_NOSYNC)) {
			if ((tw = _dm_snprintf(params + pos, paramsize - pos, "nosync ")) < 0) {
                       		stack; /* Out of space */
                       		return -1;
               		}
			pos += tw;
		} else if ((seg->flags & DM_FORCESYNC)) {
			if ((tw = _dm_snprintf(params + pos, paramsize - pos, "sync ")) < 0) {
                       		stack; /* Out of space */
                       		return -1;
               		}
			pos += tw;
		}

		if ((seg->flags & DM_BLOCK_ON_ERROR)) {
			if ((tw = _dm_snprintf(params + pos, paramsize - pos, "block_on_error ")) < 0) {
                       		stack; /* Out of space */
                       		return -1;
               		}
			pos += tw;
		}

		if ((tw = _dm_snprintf(params + pos, paramsize - pos, "%u ", seg->mirror_area_count)) < 0) {
                       	stack; /* Out of space */
                       	return -1;
               	}
		pos += tw;

		break;
	case SEG_SNAPSHOT:
		if (!_build_dev_string(originbuf, sizeof(originbuf), seg->origin))
			return_0;
		if (!_build_dev_string(cowbuf, sizeof(cowbuf), seg->cow))
			return_0;
		if ((pos = _dm_snprintf(params, paramsize, "%s %s %c %d",
                                        originbuf, cowbuf,
					seg->persistent ? 'P' : 'N',
                                        seg->chunk_size)) < 0) {
                        stack;	/* Out of space */
                        return -1;
                }
		break;
	case SEG_SNAPSHOT_ORIGIN:
		if (!_build_dev_string(originbuf, sizeof(originbuf), seg->origin))
			return_0;
		if ((pos = _dm_snprintf(params, paramsize, "%s",
                                        originbuf)) < 0) {
                        stack;	/* Out of space */
                        return -1;
                }
		break;
	case SEG_STRIPED:
		if ((pos = _dm_snprintf(params, paramsize, "%u %u ",
                                         seg->area_count,
                                         seg->stripe_size)) < 0) {
                        stack;	/* Out of space */
                        return -1;
                }
		break;
	}

	switch(seg->type) {
	case SEG_ERROR:
	case SEG_SNAPSHOT:
	case SEG_SNAPSHOT_ORIGIN:
	case SEG_ZERO:
		break;
	case SEG_LINEAR:
	case SEG_MIRRORED:
	case SEG_STRIPED:
		if ((r = _emit_areas_line(dmt, seg, params, paramsize, &pos)) <= 0) {
			stack;
			return r;
		}
		break;
	}

	log_debug("Adding target: %" PRIu64 " %" PRIu64 " %s %s",
		  *seg_start, seg->size, dm_segtypes[seg->type].target, params);

	if (!dm_task_add_target(dmt, *seg_start, seg->size, dm_segtypes[seg->type].target, params))
		return_0;

	*seg_start += seg->size;

	return 1;
}

static int _emit_segment(struct dm_task *dmt, struct load_segment *seg,
			 uint64_t *seg_start)
{
	char *params;
	size_t paramsize = 4096;
	int ret;

	do {
		if (!(params = dm_malloc(paramsize))) {
			log_error("Insufficient space for target parameters.");
			return 0;
		}

		ret = _emit_segment_line(dmt, seg, seg_start, params, paramsize);
		dm_free(params);

		if (!ret)
			stack;

		if (ret >= 0)
			return ret;

		log_debug("Insufficient space in params[%" PRIsize_t
			  "] for target parameters.", paramsize);

		paramsize *= 2;
	} while (paramsize < MAX_TARGET_PARAMSIZE);

	log_error("Target parameter size too big. Aborting.");
	return 0;
}

static int _load_node(struct dm_tree_node *dnode)
{
	int r = 0;
	struct dm_task *dmt;
	struct load_segment *seg;
	uint64_t seg_start = 0;

	log_verbose("Loading %s table", dnode->name);

	if (!(dmt = dm_task_create(DM_DEVICE_RELOAD))) {
		log_error("Reload dm_task creation failed for %s", dnode->name);
		return 0;
	}

	if (!dm_task_set_major(dmt, dnode->info.major) ||
	    !dm_task_set_minor(dmt, dnode->info.minor)) {
		log_error("Failed to set device number for %s reload.", dnode->name);
		goto out;
	}

	if (dnode->props.read_only && !dm_task_set_ro(dmt)) {
		log_error("Failed to set read only flag for %s", dnode->name);
		goto out;
	}

	if (!dm_task_no_open_count(dmt))
		log_error("Failed to disable open_count");

	list_iterate_items(seg, &dnode->props.segs)
		if (!_emit_segment(dmt, seg, &seg_start))
			goto_out;

	if (!dm_task_suppress_identical_reload(dmt))
		log_error("Failed to suppress reload of identical tables.");

	if ((r = dm_task_run(dmt))) {
		r = dm_task_get_info(dmt, &dnode->info);
		if (r && !dnode->info.inactive_table)
			log_verbose("Suppressed %s identical table reload.",
				    dnode->name);
	}

	dnode->props.segment_count = 0;

out:
	dm_task_destroy(dmt);

	return r;
}

int dm_tree_preload_children(struct dm_tree_node *dnode,
				 const char *uuid_prefix,
				 size_t uuid_prefix_len)
{
	void *handle = NULL;
	struct dm_tree_node *child;
	struct dm_info newinfo;
	const char *name;

	/* Preload children first */
	while ((child = dm_tree_next_child(&handle, dnode, 0))) {
		/* Skip existing non-device-mapper devices */
		if (!child->info.exists && child->info.major)
			continue;

		/* Ignore if it doesn't belong to this VG */
		if (child->info.exists &&
		    !_uuid_prefix_matches(child->uuid, uuid_prefix, uuid_prefix_len))
			continue;

		if (dm_tree_node_num_children(child, 0))
			dm_tree_preload_children(child, uuid_prefix, uuid_prefix_len);

		if (!(name = dm_tree_node_get_name(child))) {
			stack;
			continue;
		}

		/* FIXME Cope if name exists with no uuid? */
		if (!child->info.exists) {
			if (!_create_node(child)) {
				stack;
				return 0;
			}
		}

		if (!child->info.inactive_table && child->props.segment_count) {
			if (!_load_node(child)) {
				stack;
				return 0;
			}
		}

		/* Resume device immediately if it has parents */
		if (!dm_tree_node_num_children(child, 1))
			continue;

		if (!child->info.inactive_table && !child->info.suspended)
			continue;

		if (!_resume_node(name, child->info.major, child->info.minor, &newinfo)) {
			log_error("Unable to resume %s (%" PRIu32
				  ":%" PRIu32 ")", name, child->info.major,
				  child->info.minor);
			continue;
		}

		/* Update cached info */
		child->info = newinfo;
	}

	handle = NULL;

	return 1;
}

/*
 * Returns 1 if unsure.
 */
int dm_tree_children_use_uuid(struct dm_tree_node *dnode,
				 const char *uuid_prefix,
				 size_t uuid_prefix_len)
{
	void *handle = NULL;
	struct dm_tree_node *child = dnode;
	const char *uuid;

	while ((child = dm_tree_next_child(&handle, dnode, 0))) {
		if (!(uuid = dm_tree_node_get_uuid(child))) {
			log_error("Failed to get uuid for dtree node.");
			return 1;
		}

		if (_uuid_prefix_matches(uuid, uuid_prefix, uuid_prefix_len))
			return 1;

		if (dm_tree_node_num_children(child, 0))
			dm_tree_children_use_uuid(child, uuid_prefix, uuid_prefix_len);
	}

	return 0;
}

/*
 * Target functions
 */
static struct load_segment *_add_segment(struct dm_tree_node *dnode, unsigned type, uint64_t size)
{
	struct load_segment *seg;

	if (!(seg = dm_pool_zalloc(dnode->dtree->mem, sizeof(*seg)))) {
		log_error("dtree node segment allocation failed");
		return NULL;
	}

	seg->type = type;
	seg->size = size;
	seg->area_count = 0;
	list_init(&seg->areas);
	seg->stripe_size = 0;
	seg->persistent = 0;
	seg->chunk_size = 0;
	seg->cow = NULL;
	seg->origin = NULL;

	list_add(&dnode->props.segs, &seg->list);
	dnode->props.segment_count++;

	return seg;
}

int dm_tree_node_add_snapshot_origin_target(struct dm_tree_node *dnode,
                                               uint64_t size,
                                               const char *origin_uuid)
{
	struct load_segment *seg;
	struct dm_tree_node *origin_node;

	if (!(seg = _add_segment(dnode, SEG_SNAPSHOT_ORIGIN, size)))
		return_0;

	if (!(origin_node = dm_tree_find_node_by_uuid(dnode->dtree, origin_uuid))) {
		log_error("Couldn't find snapshot origin uuid %s.", origin_uuid);
		return 0;
	}

	seg->origin = origin_node;
	if (!_link_tree_nodes(dnode, origin_node))
		return_0;

	/* Resume snapshot origins after new snapshots */
	dnode->activation_priority = 1;

	return 1;
}

int dm_tree_node_add_snapshot_target(struct dm_tree_node *node,
                                        uint64_t size,
                                        const char *origin_uuid,
                                        const char *cow_uuid,
                                        int persistent,
                                        uint32_t chunk_size)
{
	struct load_segment *seg;
	struct dm_tree_node *origin_node, *cow_node;

	if (!(seg = _add_segment(node, SEG_SNAPSHOT, size)))
		return_0;

	if (!(origin_node = dm_tree_find_node_by_uuid(node->dtree, origin_uuid))) {
		log_error("Couldn't find snapshot origin uuid %s.", origin_uuid);
		return 0;
	}

	seg->origin = origin_node;
	if (!_link_tree_nodes(node, origin_node))
		return_0;

	if (!(cow_node = dm_tree_find_node_by_uuid(node->dtree, cow_uuid))) {
		log_error("Couldn't find snapshot origin uuid %s.", cow_uuid);
		return 0;
	}

	seg->cow = cow_node;
	if (!_link_tree_nodes(node, cow_node))
		return_0;

	seg->persistent = persistent ? 1 : 0;
	seg->chunk_size = chunk_size;

	return 1;
}

int dm_tree_node_add_error_target(struct dm_tree_node *node,
                                     uint64_t size)
{
	if (!_add_segment(node, SEG_ERROR, size))
		return_0;

	return 1;
}

int dm_tree_node_add_zero_target(struct dm_tree_node *node,
                                    uint64_t size)
{
	if (!_add_segment(node, SEG_ZERO, size))
		return_0;

	return 1;
}

int dm_tree_node_add_linear_target(struct dm_tree_node *node,
                                      uint64_t size)
{
	if (!_add_segment(node, SEG_LINEAR, size))
		return_0;

	return 1;
}

int dm_tree_node_add_striped_target(struct dm_tree_node *node,
                                       uint64_t size,
                                       uint32_t stripe_size)
{
	struct load_segment *seg;

	if (!(seg = _add_segment(node, SEG_STRIPED, size)))
		return_0;

	seg->stripe_size = stripe_size;

	return 1;
}

int dm_tree_node_add_mirror_target_log(struct dm_tree_node *node,
					  uint32_t region_size,
					  unsigned clustered, 
					  const char *log_uuid,
					  unsigned area_count,
					  uint32_t flags)
{
	struct dm_tree_node *log_node = NULL;
	struct load_segment *seg;

	if (!node->props.segment_count) {
		log_error("Internal error: Attempt to add target area to missing segment.");
		return 0;
	}

	seg = list_item(list_last(&node->props.segs), struct load_segment);

	if (log_uuid) {
		if (!(seg->uuid = dm_pool_strdup(node->dtree->mem, log_uuid))) {
			log_error("log uuid pool_strdup failed");
			return 0;
		}
		if (!(flags & DM_CORELOG)) {
			if (!(log_node = dm_tree_find_node_by_uuid(node->dtree, log_uuid))) {
				log_error("Couldn't find mirror log uuid %s.", log_uuid);
				return 0;
			}

			if (!_link_tree_nodes(node, log_node))
				return_0;
		}
	}

	seg->log = log_node;
	seg->region_size = region_size;
	seg->clustered = clustered;
	seg->mirror_area_count = area_count;
	seg->flags = flags;

	return 1;
}

int dm_tree_node_add_mirror_target(struct dm_tree_node *node,
                                      uint64_t size)
{
	struct load_segment *seg;

	if (!(seg = _add_segment(node, SEG_MIRRORED, size)))
		return_0;

	return 1;
}

static int _add_area(struct dm_tree_node *node, struct load_segment *seg, struct dm_tree_node *dev_node, uint64_t offset)
{
	struct seg_area *area;

	if (!(area = dm_pool_zalloc(node->dtree->mem, sizeof (*area)))) {
		log_error("Failed to allocate target segment area.");
		return 0;
	}

	area->dev_node = dev_node;
	area->offset = offset;

	list_add(&seg->areas, &area->list);
	seg->area_count++;

	return 1;
}

int dm_tree_node_add_target_area(struct dm_tree_node *node,
                                    const char *dev_name,
                                    const char *uuid,
                                    uint64_t offset)
{
	struct load_segment *seg;
	struct stat info;
	struct dm_tree_node *dev_node;

	if ((!dev_name || !*dev_name) && (!uuid || !*uuid)) {
		log_error("dm_tree_node_add_target_area called without device");
		return 0;
	}

	if (uuid) {
		if (!(dev_node = dm_tree_find_node_by_uuid(node->dtree, uuid))) {
			log_error("Couldn't find area uuid %s.", uuid);
			return 0;
		}
		if (!_link_tree_nodes(node, dev_node))
			return_0;
	} else {
        	if (stat(dev_name, &info) < 0) {
			log_error("Device %s not found.", dev_name);
			return 0;
		}

        	if (!S_ISBLK(info.st_mode)) {
			log_error("Device %s is not a block device.", dev_name);
			return 0;
		}

		/* FIXME Check correct macro use */
		if (!(dev_node = _add_dev(node->dtree, node, MAJOR(info.st_rdev), MINOR(info.st_rdev))))
			return_0;
	}

	if (!node->props.segment_count) {
		log_error("Internal error: Attempt to add target area to missing segment.");
		return 0;
	}

	seg = list_item(list_last(&node->props.segs), struct load_segment);

	if (!_add_area(node, seg, dev_node, offset))
		return_0;

	return 1;
}