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authorJens Axboe <axboe@fb.com>2014-05-19 20:01:52 -0600
committerJens Axboe <axboe@fb.com>2014-05-19 20:01:52 -0600
commit719c555f4424b194905aa3512a754c0444f27ce8 (patch)
tree6afd4d62345f1fac7046e23d8907ac555846eb5a /mm/bounce.c
parent39a9f97e5ea99e048c4980c23cf197f6e77995cb (diff)
downloadlinux-sh-719c555f4424b194905aa3512a754c0444f27ce8.tar.gz
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 <tom.leiming@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'mm/bounce.c')
-rw-r--r--mm/bounce.c287
1 files changed, 0 insertions, 287 deletions
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 <linux/mm.h>
-#include <linux/export.h>
-#include <linux/swap.h>
-#include <linux/gfp.h>
-#include <linux/bio.h>
-#include <linux/pagemap.h>
-#include <linux/mempool.h>
-#include <linux/blkdev.h>
-#include <linux/init.h>
-#include <linux/hash.h>
-#include <linux/highmem.h>
-#include <linux/bootmem.h>
-#include <asm/tlbflush.h>
-
-#include <trace/events/block.h>
-
-#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);