diff options
Diffstat (limited to 'block/blk-settings.c')
| -rw-r--r-- | block/blk-settings.c | 40 |
1 files changed, 28 insertions, 12 deletions
diff --git a/block/blk-settings.c b/block/blk-settings.c index 34b721a2743a..9741d1d83e98 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -172,15 +172,13 @@ EXPORT_SYMBOL(blk_queue_max_hw_sectors); * * Description: * If a driver doesn't want IOs to cross a given chunk size, it can set - * this limit and prevent merging across chunks. Note that the chunk size - * must currently be a power-of-2 in sectors. Also note that the block - * layer must accept a page worth of data at any offset. So if the - * crossing of chunks is a hard limitation in the driver, it must still be - * prepared to split single page bios. + * this limit and prevent merging across chunks. Note that the block layer + * must accept a page worth of data at any offset. So if the crossing of + * chunks is a hard limitation in the driver, it must still be prepared + * to split single page bios. **/ void blk_queue_chunk_sectors(struct request_queue *q, unsigned int chunk_sectors) { - BUG_ON(!is_power_of_2(chunk_sectors)); q->limits.chunk_sectors = chunk_sectors; } EXPORT_SYMBOL(blk_queue_chunk_sectors); @@ -374,6 +372,19 @@ void blk_queue_alignment_offset(struct request_queue *q, unsigned int offset) } EXPORT_SYMBOL(blk_queue_alignment_offset); +void blk_queue_update_readahead(struct request_queue *q) +{ + /* + * For read-ahead of large files to be effective, we need to read ahead + * at least twice the optimal I/O size. + */ + q->backing_dev_info->ra_pages = + max(queue_io_opt(q) * 2 / PAGE_SIZE, VM_READAHEAD_PAGES); + q->backing_dev_info->io_pages = + queue_max_sectors(q) >> (PAGE_SHIFT - 9); +} +EXPORT_SYMBOL_GPL(blk_queue_update_readahead); + /** * blk_limits_io_min - set minimum request size for a device * @limits: the queue limits @@ -452,6 +463,8 @@ EXPORT_SYMBOL(blk_limits_io_opt); void blk_queue_io_opt(struct request_queue *q, unsigned int opt) { blk_limits_io_opt(&q->limits, opt); + q->backing_dev_info->ra_pages = + max(queue_io_opt(q) * 2 / PAGE_SIZE, VM_READAHEAD_PAGES); } EXPORT_SYMBOL(blk_queue_io_opt); @@ -534,6 +547,7 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, t->io_min = max(t->io_min, b->io_min); t->io_opt = lcm_not_zero(t->io_opt, b->io_opt); + t->chunk_sectors = lcm_not_zero(t->chunk_sectors, b->chunk_sectors); /* Physical block size a multiple of the logical block size? */ if (t->physical_block_size & (t->logical_block_size - 1)) { @@ -556,6 +570,13 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, ret = -1; } + /* chunk_sectors a multiple of the physical block size? */ + if ((t->chunk_sectors << 9) & (t->physical_block_size - 1)) { + t->chunk_sectors = 0; + t->misaligned = 1; + ret = -1; + } + t->raid_partial_stripes_expensive = max(t->raid_partial_stripes_expensive, b->raid_partial_stripes_expensive); @@ -594,10 +615,6 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, t->discard_granularity; } - if (b->chunk_sectors) - t->chunk_sectors = min_not_zero(t->chunk_sectors, - b->chunk_sectors); - t->zoned = max(t->zoned, b->zoned); return ret; } @@ -629,8 +646,7 @@ void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, top, bottom); } - t->backing_dev_info->io_pages = - t->limits.max_sectors >> (PAGE_SHIFT - 9); + blk_queue_update_readahead(disk->queue); } EXPORT_SYMBOL(disk_stack_limits); |