diff options
Diffstat (limited to 'drivers/s390/block/dasd_fba.c')
| -rw-r--r-- | drivers/s390/block/dasd_fba.c | 45 |
1 files changed, 32 insertions, 13 deletions
diff --git a/drivers/s390/block/dasd_fba.c b/drivers/s390/block/dasd_fba.c index 56007a3e7f11..cbb770824226 100644 --- a/drivers/s390/block/dasd_fba.c +++ b/drivers/s390/block/dasd_fba.c @@ -770,27 +770,46 @@ dasd_fba_dump_sense(struct dasd_device *device, struct dasd_ccw_req * req, } /* - * max_blocks is dependent on the amount of storage that is available - * in the static io buffer for each device. Currently each device has - * 8192 bytes (=2 pages). For 64 bit one dasd_mchunkt_t structure has - * 24 bytes, the struct dasd_ccw_req has 136 bytes and each block can use - * up to 16 bytes (8 for the ccw and 8 for the idal pointer). In - * addition we have one define extent ccw + 16 bytes of data and a - * locate record ccw for each block (stupid devices!) + 16 bytes of data. - * That makes: - * (8192 - 24 - 136 - 8 - 16) / 40 = 200.2 blocks at maximum. - * We want to fit two into the available memory so that we can immediately - * start the next request if one finishes off. That makes 100.1 blocks - * for one request. Give a little safety and the result is 96. + * Initialize block layer request queue. */ +static void dasd_fba_setup_blk_queue(struct dasd_block *block) +{ + unsigned int logical_block_size = block->bp_block; + struct request_queue *q = block->request_queue; + unsigned int max_bytes, max_discard_sectors; + int max; + + max = DASD_FBA_MAX_BLOCKS << block->s2b_shift; + blk_queue_flag_set(QUEUE_FLAG_NONROT, q); + q->limits.max_dev_sectors = max; + blk_queue_logical_block_size(q, logical_block_size); + blk_queue_max_hw_sectors(q, max); + blk_queue_max_segments(q, USHRT_MAX); + /* With page sized segments each segment can be translated into one idaw/tidaw */ + blk_queue_max_segment_size(q, PAGE_SIZE); + blk_queue_segment_boundary(q, PAGE_SIZE - 1); + + q->limits.discard_granularity = logical_block_size; + q->limits.discard_alignment = PAGE_SIZE; + + /* Calculate max_discard_sectors and make it PAGE aligned */ + max_bytes = USHRT_MAX * logical_block_size; + max_bytes = ALIGN_DOWN(max_bytes, PAGE_SIZE); + max_discard_sectors = max_bytes / logical_block_size; + + blk_queue_max_discard_sectors(q, max_discard_sectors); + blk_queue_max_write_zeroes_sectors(q, max_discard_sectors); + blk_queue_flag_set(QUEUE_FLAG_DISCARD, q); +} + static struct dasd_discipline dasd_fba_discipline = { .owner = THIS_MODULE, .name = "FBA ", .ebcname = "FBA ", - .max_blocks = 96, .check_device = dasd_fba_check_characteristics, .do_analysis = dasd_fba_do_analysis, .verify_path = dasd_generic_verify_path, + .setup_blk_queue = dasd_fba_setup_blk_queue, .fill_geometry = dasd_fba_fill_geometry, .start_IO = dasd_start_IO, .term_IO = dasd_term_IO, |