From 719c555f4424b194905aa3512a754c0444f27ce8 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Mon, 19 May 2014 20:01:52 -0600 Subject: block: move mm/bounce.c to block/ Continue moving some of the block files that are scattered around. bounce.c contains only code for bouncing the contents of a bio. It's block proper code, not mm code. Suggested-by: Ming Lei Signed-off-by: Jens Axboe --- mm/bounce.c | 287 ------------------------------------------------------------ 1 file changed, 287 deletions(-) delete mode 100644 mm/bounce.c (limited to 'mm/bounce.c') diff --git a/mm/bounce.c b/mm/bounce.c deleted file mode 100644 index 523918b8c6dc..000000000000 --- a/mm/bounce.c +++ /dev/null @@ -1,287 +0,0 @@ -/* bounce buffer handling for block devices - * - * - Split from highmem.c - */ - -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#include - -#define POOL_SIZE 64 -#define ISA_POOL_SIZE 16 - -static mempool_t *page_pool, *isa_page_pool; - -#if defined(CONFIG_HIGHMEM) || defined(CONFIG_NEED_BOUNCE_POOL) -static __init int init_emergency_pool(void) -{ -#if defined(CONFIG_HIGHMEM) && !defined(CONFIG_MEMORY_HOTPLUG) - if (max_pfn <= max_low_pfn) - return 0; -#endif - - page_pool = mempool_create_page_pool(POOL_SIZE, 0); - BUG_ON(!page_pool); - printk("bounce pool size: %d pages\n", POOL_SIZE); - - return 0; -} - -__initcall(init_emergency_pool); -#endif - -#ifdef CONFIG_HIGHMEM -/* - * highmem version, map in to vec - */ -static void bounce_copy_vec(struct bio_vec *to, unsigned char *vfrom) -{ - unsigned long flags; - unsigned char *vto; - - local_irq_save(flags); - vto = kmap_atomic(to->bv_page); - memcpy(vto + to->bv_offset, vfrom, to->bv_len); - kunmap_atomic(vto); - local_irq_restore(flags); -} - -#else /* CONFIG_HIGHMEM */ - -#define bounce_copy_vec(to, vfrom) \ - memcpy(page_address((to)->bv_page) + (to)->bv_offset, vfrom, (to)->bv_len) - -#endif /* CONFIG_HIGHMEM */ - -/* - * allocate pages in the DMA region for the ISA pool - */ -static void *mempool_alloc_pages_isa(gfp_t gfp_mask, void *data) -{ - return mempool_alloc_pages(gfp_mask | GFP_DMA, data); -} - -/* - * gets called "every" time someone init's a queue with BLK_BOUNCE_ISA - * as the max address, so check if the pool has already been created. - */ -int init_emergency_isa_pool(void) -{ - if (isa_page_pool) - return 0; - - isa_page_pool = mempool_create(ISA_POOL_SIZE, mempool_alloc_pages_isa, - mempool_free_pages, (void *) 0); - BUG_ON(!isa_page_pool); - - printk("isa bounce pool size: %d pages\n", ISA_POOL_SIZE); - return 0; -} - -/* - * Simple bounce buffer support for highmem pages. Depending on the - * queue gfp mask set, *to may or may not be a highmem page. kmap it - * always, it will do the Right Thing - */ -static void copy_to_high_bio_irq(struct bio *to, struct bio *from) -{ - unsigned char *vfrom; - struct bio_vec tovec, *fromvec = from->bi_io_vec; - struct bvec_iter iter; - - bio_for_each_segment(tovec, to, iter) { - if (tovec.bv_page != fromvec->bv_page) { - /* - * fromvec->bv_offset and fromvec->bv_len might have - * been modified by the block layer, so use the original - * copy, bounce_copy_vec already uses tovec->bv_len - */ - vfrom = page_address(fromvec->bv_page) + - tovec.bv_offset; - - bounce_copy_vec(&tovec, vfrom); - flush_dcache_page(tovec.bv_page); - } - - fromvec++; - } -} - -static void bounce_end_io(struct bio *bio, mempool_t *pool, int err) -{ - struct bio *bio_orig = bio->bi_private; - struct bio_vec *bvec, *org_vec; - int i; - - if (test_bit(BIO_EOPNOTSUPP, &bio->bi_flags)) - set_bit(BIO_EOPNOTSUPP, &bio_orig->bi_flags); - - /* - * free up bounce indirect pages used - */ - bio_for_each_segment_all(bvec, bio, i) { - org_vec = bio_orig->bi_io_vec + i; - if (bvec->bv_page == org_vec->bv_page) - continue; - - dec_zone_page_state(bvec->bv_page, NR_BOUNCE); - mempool_free(bvec->bv_page, pool); - } - - bio_endio(bio_orig, err); - bio_put(bio); -} - -static void bounce_end_io_write(struct bio *bio, int err) -{ - bounce_end_io(bio, page_pool, err); -} - -static void bounce_end_io_write_isa(struct bio *bio, int err) -{ - - bounce_end_io(bio, isa_page_pool, err); -} - -static void __bounce_end_io_read(struct bio *bio, mempool_t *pool, int err) -{ - struct bio *bio_orig = bio->bi_private; - - if (test_bit(BIO_UPTODATE, &bio->bi_flags)) - copy_to_high_bio_irq(bio_orig, bio); - - bounce_end_io(bio, pool, err); -} - -static void bounce_end_io_read(struct bio *bio, int err) -{ - __bounce_end_io_read(bio, page_pool, err); -} - -static void bounce_end_io_read_isa(struct bio *bio, int err) -{ - __bounce_end_io_read(bio, isa_page_pool, err); -} - -#ifdef CONFIG_NEED_BOUNCE_POOL -static int must_snapshot_stable_pages(struct request_queue *q, struct bio *bio) -{ - if (bio_data_dir(bio) != WRITE) - return 0; - - if (!bdi_cap_stable_pages_required(&q->backing_dev_info)) - return 0; - - return test_bit(BIO_SNAP_STABLE, &bio->bi_flags); -} -#else -static int must_snapshot_stable_pages(struct request_queue *q, struct bio *bio) -{ - return 0; -} -#endif /* CONFIG_NEED_BOUNCE_POOL */ - -static void __blk_queue_bounce(struct request_queue *q, struct bio **bio_orig, - mempool_t *pool, int force) -{ - struct bio *bio; - int rw = bio_data_dir(*bio_orig); - struct bio_vec *to, from; - struct bvec_iter iter; - unsigned i; - - if (force) - goto bounce; - bio_for_each_segment(from, *bio_orig, iter) - if (page_to_pfn(from.bv_page) > queue_bounce_pfn(q)) - goto bounce; - - return; -bounce: - bio = bio_clone_bioset(*bio_orig, GFP_NOIO, fs_bio_set); - - bio_for_each_segment_all(to, bio, i) { - struct page *page = to->bv_page; - - if (page_to_pfn(page) <= queue_bounce_pfn(q) && !force) - continue; - - inc_zone_page_state(to->bv_page, NR_BOUNCE); - to->bv_page = mempool_alloc(pool, q->bounce_gfp); - - if (rw == WRITE) { - char *vto, *vfrom; - - flush_dcache_page(page); - - vto = page_address(to->bv_page) + to->bv_offset; - vfrom = kmap_atomic(page) + to->bv_offset; - memcpy(vto, vfrom, to->bv_len); - kunmap_atomic(vfrom); - } - } - - trace_block_bio_bounce(q, *bio_orig); - - bio->bi_flags |= (1 << BIO_BOUNCED); - - if (pool == page_pool) { - bio->bi_end_io = bounce_end_io_write; - if (rw == READ) - bio->bi_end_io = bounce_end_io_read; - } else { - bio->bi_end_io = bounce_end_io_write_isa; - if (rw == READ) - bio->bi_end_io = bounce_end_io_read_isa; - } - - bio->bi_private = *bio_orig; - *bio_orig = bio; -} - -void blk_queue_bounce(struct request_queue *q, struct bio **bio_orig) -{ - int must_bounce; - mempool_t *pool; - - /* - * Data-less bio, nothing to bounce - */ - if (!bio_has_data(*bio_orig)) - return; - - must_bounce = must_snapshot_stable_pages(q, *bio_orig); - - /* - * for non-isa bounce case, just check if the bounce pfn is equal - * to or bigger than the highest pfn in the system -- in that case, - * don't waste time iterating over bio segments - */ - if (!(q->bounce_gfp & GFP_DMA)) { - if (queue_bounce_pfn(q) >= blk_max_pfn && !must_bounce) - return; - pool = page_pool; - } else { - BUG_ON(!isa_page_pool); - pool = isa_page_pool; - } - - /* - * slow path - */ - __blk_queue_bounce(q, bio_orig, pool, must_bounce); -} - -EXPORT_SYMBOL(blk_queue_bounce); -- cgit v1.2.3