os-area.c

linux内核源码

		&& i->match_id.key != (int)i->idx->key)
		goto next;

	return 1;
}

static int db_delete_64(struct os_area_db *db, const struct os_area_db_id *id)
{
	struct db_iterator i;

	for (i.db = NULL; db_for_each_64(db, id, &i); ) {

		pr_debug("%s:%d: got (%d:%d) %llxh\n", __func__, __LINE__,
			i.idx->owner, i.idx->key,
			(unsigned long long)*i.value_64);

		i.idx->owner = 0;
		i.idx->key = 0;
		*i.value_64 = 0;
	}
	return 0;
}

static int db_set_64(struct os_area_db *db, const struct os_area_db_id *id,
	uint64_t value)
{
	struct db_iterator i;

	pr_debug("%s:%d: (%d:%d) <= %llxh\n", __func__, __LINE__,
		id->owner, id->key, (unsigned long long)value);

	if (!id->owner || id->owner == OS_AREA_DB_OWNER_ANY
		|| id->key == OS_AREA_DB_KEY_ANY) {
		pr_debug("%s:%d: bad id: (%d:%d)\n", __func__,
			__LINE__, id->owner, id->key);
		return -1;
	}

	db_delete_64(db, id);

	i.db = NULL;
	if (db_for_each_64(db, &os_area_db_id_empty, &i)) {

		pr_debug("%s:%d: got (%d:%d) %llxh\n", __func__, __LINE__,
			i.idx->owner, i.idx->key,
			(unsigned long long)*i.value_64);

		i.idx->owner = id->owner;
		i.idx->key = id->key;
		*i.value_64 = value;

		pr_debug("%s:%d: set (%d:%d) <= %llxh\n", __func__, __LINE__,
			i.idx->owner, i.idx->key,
			(unsigned long long)*i.value_64);
		return 0;
	}
	pr_debug("%s:%d: database full.\n",
		__func__, __LINE__);
	return -1;
}

static int db_get_64(const struct os_area_db *db,
	const struct os_area_db_id *id, uint64_t *value)
{
	struct db_iterator i;

	i.db = NULL;
	if (db_for_each_64(db, id, &i)) {
		*value = *i.value_64;
		pr_debug("%s:%d: found %lld\n", __func__, __LINE__,
				(long long int)*i.value_64);
		return 0;
	}
	pr_debug("%s:%d: not found\n", __func__, __LINE__);
	return -1;
}

static int db_get_rtc_diff(const struct os_area_db *db, int64_t *rtc_diff)
{
	return db_get_64(db, &os_area_db_id_rtc_diff, (uint64_t*)rtc_diff);
}

#define dump_db(a) _dump_db(a, __func__, __LINE__)
static void _dump_db(const struct os_area_db *db, const char *func,
	int line)
{
	char str[sizeof(db->magic_num) + 1];

	dump_field(str, db->magic_num, sizeof(db->magic_num));
	pr_debug("%s:%d: db.magic_num:      '%s'\n", func, line,
		str);
	pr_debug("%s:%d: db.version:         %u\n", func, line,
		db->version);
	pr_debug("%s:%d: db.index_64:        %u\n", func, line,
		db->index_64);
	pr_debug("%s:%d: db.count_64:        %u\n", func, line,
		db->count_64);
	pr_debug("%s:%d: db.index_32:        %u\n", func, line,
		db->index_32);
	pr_debug("%s:%d: db.count_32:        %u\n", func, line,
		db->count_32);
	pr_debug("%s:%d: db.index_16:        %u\n", func, line,
		db->index_16);
	pr_debug("%s:%d: db.count_16:        %u\n", func, line,
		db->count_16);
}

static void os_area_db_init(struct os_area_db *db)
{
	enum {
		HEADER_SIZE = offsetof(struct os_area_db, _db_data),
		INDEX_64_COUNT = 64,
		VALUES_64_COUNT = 57,
		INDEX_32_COUNT = 64,
		VALUES_32_COUNT = 57,
		INDEX_16_COUNT = 64,
		VALUES_16_COUNT = 57,
	};

	memset(db, 0, sizeof(struct os_area_db));

	memcpy(db->magic_num, OS_AREA_DB_MAGIC_NUM, sizeof(db->magic_num));
	db->version = 1;
	db->index_64 = HEADER_SIZE;
	db->count_64 = VALUES_64_COUNT;
	db->index_32 = HEADER_SIZE
			+ INDEX_64_COUNT * sizeof(struct db_index)
			+ VALUES_64_COUNT * sizeof(u64);
	db->count_32 = VALUES_32_COUNT;
	db->index_16 = HEADER_SIZE
			+ INDEX_64_COUNT * sizeof(struct db_index)
			+ VALUES_64_COUNT * sizeof(u64)
			+ INDEX_32_COUNT * sizeof(struct db_index)
			+ VALUES_32_COUNT * sizeof(u32);
	db->count_16 = VALUES_16_COUNT;

	/* Rules to check db layout. */

	BUILD_BUG_ON(sizeof(struct db_index) != 1);
	BUILD_BUG_ON(sizeof(struct os_area_db) != 2 * OS_AREA_SEGMENT_SIZE);
	BUILD_BUG_ON(INDEX_64_COUNT & 0x7);
	BUILD_BUG_ON(VALUES_64_COUNT > INDEX_64_COUNT);
	BUILD_BUG_ON(INDEX_32_COUNT & 0x7);
	BUILD_BUG_ON(VALUES_32_COUNT > INDEX_32_COUNT);
	BUILD_BUG_ON(INDEX_16_COUNT & 0x7);
	BUILD_BUG_ON(VALUES_16_COUNT > INDEX_16_COUNT);
	BUILD_BUG_ON(HEADER_SIZE
			+ INDEX_64_COUNT * sizeof(struct db_index)
			+ VALUES_64_COUNT * sizeof(u64)
			+ INDEX_32_COUNT * sizeof(struct db_index)
			+ VALUES_32_COUNT * sizeof(u32)
			+ INDEX_16_COUNT * sizeof(struct db_index)
			+ VALUES_16_COUNT * sizeof(u16)
			> sizeof(struct os_area_db));
}

/**
 * update_flash_db - Helper for os_area_queue_work_handler.
 *
 */

static void update_flash_db(void)
{
	int result;
	int file;
	off_t offset;
	ssize_t count;
	static const unsigned int buf_len = 8 * OS_AREA_SEGMENT_SIZE;
	const struct os_area_header *header;
	struct os_area_db* db;

	/* Read in header and db from flash. */

	file = sys_open("/dev/ps3flash", O_RDWR, 0);

	if (file < 0) {
		pr_debug("%s:%d sys_open failed\n", __func__, __LINE__);
		goto fail_open;
	}

	header = kmalloc(buf_len, GFP_KERNEL);

	if (!header) {
		pr_debug("%s:%d kmalloc failed\n", __func__, __LINE__);
		goto fail_malloc;
	}

	offset = sys_lseek(file, 0, SEEK_SET);

	if (offset != 0) {
		pr_debug("%s:%d sys_lseek failed\n", __func__, __LINE__);
		goto fail_header_seek;
	}

	count = sys_read(file, (char __user *)header, buf_len);

	result = count < OS_AREA_SEGMENT_SIZE || verify_header(header)
		|| count < header->db_area_offset * OS_AREA_SEGMENT_SIZE;

	if (result) {
		pr_debug("%s:%d verify_header failed\n", __func__, __LINE__);
		dump_header(header);
		goto fail_header;
	}

	/* Now got a good db offset and some maybe good db data. */

	db = (void*)header + header->db_area_offset * OS_AREA_SEGMENT_SIZE;

	result = db_verify(db);

	if (result) {
		printk(KERN_NOTICE "%s:%d: Verify of flash database failed, "
			"formatting.\n", __func__, __LINE__);
		dump_db(db);
		os_area_db_init(db);
	}

	/* Now got good db data. */

	db_set_64(db, &os_area_db_id_rtc_diff, saved_params.rtc_diff);

	offset = sys_lseek(file, header->db_area_offset * OS_AREA_SEGMENT_SIZE,
		SEEK_SET);

	if (offset != header->db_area_offset * OS_AREA_SEGMENT_SIZE) {
		pr_debug("%s:%d sys_lseek failed\n", __func__, __LINE__);
		goto fail_db_seek;
	}

	count = sys_write(file, (const char __user *)db,
		sizeof(struct os_area_db));

	if (count < sizeof(struct os_area_db)) {
		pr_debug("%s:%d sys_write failed\n", __func__, __LINE__);
	}

fail_db_seek:
fail_header:
fail_header_seek:
	kfree(header);
fail_malloc:
	sys_close(file);
fail_open:
	return;
}

/**
 * os_area_queue_work_handler - Asynchronous write handler.
 *
 * An asynchronous write for flash memory and the device tree.  Do not
 * call directly, use os_area_queue_work().
 */

static void os_area_queue_work_handler(struct work_struct *work)
{
	struct device_node *node;

	pr_debug(" -> %s:%d\n", __func__, __LINE__);

	node = of_find_node_by_path("/");

	if (node) {
		os_area_set_property(node, &property_rtc_diff);
		of_node_put(node);
	} else
		pr_debug("%s:%d of_find_node_by_path failed\n",
			__func__, __LINE__);

#if defined(CONFIG_PS3_FLASH) || defined(CONFIG_PS3_FLASH_MODULE)
	update_flash_db();
#else
	printk(KERN_WARNING "%s:%d: No flash rom driver configured.\n",
		__func__, __LINE__);
#endif
	pr_debug(" <- %s:%d\n", __func__, __LINE__);
}

static void os_area_queue_work(void)
{
	static DECLARE_WORK(q, os_area_queue_work_handler);

	wmb();
	schedule_work(&q);
}

/**
 * ps3_os_area_save_params - Copy data from os area mirror to @saved_params.
 *
 * For the convenience of the guest the HV makes a copy of the os area in
 * flash to a high address in the boot memory region and then puts that RAM
 * address and the byte count into the repository for retrieval by the guest.
 * We copy the data we want into a static variable and allow the memory setup
 * by the HV to be claimed by the lmb manager.
 *
 * The os area mirror will not be available to a second stage kernel, and
 * the header verify will fail.  In this case, the saved_params values will
 * be set from flash memory or the passed in device tree in ps3_os_area_init().
 */

void __init ps3_os_area_save_params(void)
{
	int result;
	u64 lpar_addr;
	unsigned int size;
	struct os_area_header *header;
	struct os_area_params *params;
	struct os_area_db *db;

	pr_debug(" -> %s:%d\n", __func__, __LINE__);

	result = ps3_repository_read_boot_dat_info(&lpar_addr, &size);

	if (result) {
		pr_debug("%s:%d ps3_repository_read_boot_dat_info failed\n",
			__func__, __LINE__);
		return;
	}

	header = (struct os_area_header *)__va(lpar_addr);
	params = (struct os_area_params *)__va(lpar_addr
		+ OS_AREA_SEGMENT_SIZE);

	result = verify_header(header);

	if (result) {
		/* Second stage kernels exit here. */
		pr_debug("%s:%d verify_header failed\n", __func__, __LINE__);
		dump_header(header);
		return;
	}

	db = (struct os_area_db *)__va(lpar_addr
		+ header->db_area_offset * OS_AREA_SEGMENT_SIZE);

	dump_header(header);
	dump_params(params);
	dump_db(db);

	result = db_verify(db) || db_get_rtc_diff(db, &saved_params.rtc_diff);
	if (result)
		saved_params.rtc_diff = params->rtc_diff ? params->rtc_diff
			: SECONDS_FROM_1970_TO_2000;
	saved_params.av_multi_out = params->av_multi_out;
	saved_params.valid = 1;

	memset(header, 0, sizeof(*header));

	pr_debug(" <- %s:%d\n", __func__, __LINE__);
}

/**
 * ps3_os_area_init - Setup os area device tree properties as needed.
 */

void __init ps3_os_area_init(void)
{
	struct device_node *node;

	pr_debug(" -> %s:%d\n", __func__, __LINE__);

	node = of_find_node_by_path("/");

	if (!saved_params.valid && node) {
		/* Second stage kernels should have a dt entry. */
		os_area_get_property(node, &property_rtc_diff);
		os_area_get_property(node, &property_av_multi_out);
	}

	if(!saved_params.rtc_diff)
		saved_params.rtc_diff = SECONDS_FROM_1970_TO_2000;

	if (node) {
		os_area_set_property(node, &property_rtc_diff);
		os_area_set_property(node, &property_av_multi_out);
		of_node_put(node);
	} else
		pr_debug("%s:%d of_find_node_by_path failed\n",
			__func__, __LINE__);

	pr_debug(" <- %s:%d\n", __func__, __LINE__);
}

/**
 * ps3_os_area_get_rtc_diff - Returns the rtc diff value.
 */

u64 ps3_os_area_get_rtc_diff(void)
{
	return saved_params.rtc_diff;
}

/**
 * ps3_os_area_set_rtc_diff - Set the rtc diff value.
 *
 * An asynchronous write is needed to support writing updates from
 * the timer interrupt context.
 */

void ps3_os_area_set_rtc_diff(u64 rtc_diff)
{
	if (saved_params.rtc_diff != rtc_diff) {
		saved_params.rtc_diff = rtc_diff;
		os_area_queue_work();
	}
}

/**
 * ps3_os_area_get_av_multi_out - Returns the default video mode.
 */

enum ps3_param_av_multi_out ps3_os_area_get_av_multi_out(void)
{
    return saved_params.av_multi_out;
}
EXPORT_SYMBOL_GPL(ps3_os_area_get_av_multi_out);