-/*
- * Compute the maximum number of sectors the bdev can handle in one bio,
- * as a power of two.
- *
- * Stolen from oracleasm, thanks Joel!
- */
-static int compute_max_sectors(struct block_device *bdev)
-{
- int max_pages, max_sectors, pow_two_sectors;
-
- struct request_queue *q;
-
- q = bdev_get_queue(bdev);
- max_pages = q->max_sectors >> (PAGE_SHIFT - 9);
- if (max_pages > BIO_MAX_PAGES)
- max_pages = BIO_MAX_PAGES;
- if (max_pages > q->max_phys_segments)
- max_pages = q->max_phys_segments;
- if (max_pages > q->max_hw_segments)
- max_pages = q->max_hw_segments;
- max_pages--; /* Handle I/Os that straddle a page */
-
- if (max_pages) {
- max_sectors = max_pages << (PAGE_SHIFT - 9);
- } else {
- /* If BIO contains 1 or less than 1 page. */
- max_sectors = q->max_sectors;
- }
- /* Why is fls() 1-based???? */
- pow_two_sectors = 1 << (fls(max_sectors) - 1);
-
- return pow_two_sectors;
-}
-
-static inline void o2hb_compute_request_limits(struct o2hb_region *reg,
- unsigned int num_slots,
- unsigned int *num_bios,
- unsigned int *slots_per_bio)
-{
- unsigned int max_sectors, io_sectors;
-
- max_sectors = compute_max_sectors(reg->hr_bdev);
-
- io_sectors = num_slots << (reg->hr_block_bits - 9);
-
- *num_bios = (io_sectors + max_sectors - 1) / max_sectors;
- *slots_per_bio = max_sectors >> (reg->hr_block_bits - 9);
-
- mlog(ML_HB_BIO, "My io size is %u sectors for %u slots. This "
- "device can handle %u sectors of I/O\n", io_sectors, num_slots,
- max_sectors);
- mlog(ML_HB_BIO, "Will need %u bios holding %u slots each\n",
- *num_bios, *slots_per_bio);
-}
-