1 files changed, 19 insertions, 54 deletions

diff --git a/mm/bounce.c b/mm/bounce.c
index 5f8901768602..55f512af50c7 100644
--- a/mm/bounce.c
+++ b/mm/bounce.c
@@ -101,7 +101,7 @@ static void copy_to_high_bio_irq(struct bio *to, struct bio *from)
         struct bio_vec *tovec, *fromvec;
         int i;
 
-        __bio_for_each_segment(tovec, to, i, 0) {
+        bio_for_each_segment(tovec, to, i) {
                 fromvec = from->bi_io_vec + i;
 
                 /*
@@ -218,78 +218,43 @@ static int must_snapshot_stable_pages(struct request_queue *q, struct bio *bio)
 static void __blk_queue_bounce(struct request_queue *q, struct bio **bio_orig,
                                mempool_t *pool, int force)
 {
-        struct page *page;
-        struct bio *bio = NULL;
-        int i, rw = bio_data_dir(*bio_orig);
+        struct bio *bio;
+        int rw = bio_data_dir(*bio_orig);
         struct bio_vec *to, *from;
+        unsigned i;
 
-        bio_for_each_segment(from, *bio_orig, i) {
-                page = from->bv_page;
+        bio_for_each_segment(from, *bio_orig, i)
+                if (page_to_pfn(from->bv_page) > queue_bounce_pfn(q))
+                        goto bounce;
 
-                /*
-                 * is destination page below bounce pfn?
-                 */
-                if (page_to_pfn(page) <= queue_bounce_pfn(q) && !force)
-                        continue;
+        return;
+bounce:
+        bio = bio_clone_bioset(*bio_orig, GFP_NOIO, fs_bio_set);
 
-                /*
-                 * irk, bounce it
-                 */
-                if (!bio) {
-                        unsigned int cnt = (*bio_orig)->bi_vcnt;
-
-                        bio = bio_alloc(GFP_NOIO, cnt);
-                        memset(bio->bi_io_vec, 0, cnt * sizeof(struct bio_vec));
-                }
-                        
+        bio_for_each_segment(to, bio, i) {
+                struct page *page = to->bv_page;
 
-                to = bio->bi_io_vec + i;
+                if (page_to_pfn(page) <= queue_bounce_pfn(q) && !force)
+                        continue;
 
-                to->bv_page = mempool_alloc(pool, q->bounce_gfp);
-                to->bv_len = from->bv_len;
-                to->bv_offset = from->bv_offset;
                 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(from->bv_page);
+                        flush_dcache_page(page);
+
                         vto = page_address(to->bv_page) + to->bv_offset;
-                        vfrom = kmap(from->bv_page) + from->bv_offset;
+                        vfrom = kmap_atomic(page) + to->bv_offset;
                         memcpy(vto, vfrom, to->bv_len);
-                        kunmap(from->bv_page);
+                        kunmap_atomic(vfrom);
                 }
         }
 
-        /*
-         * no pages bounced
-         */
-        if (!bio)
-                return;
-
         trace_block_bio_bounce(q, *bio_orig);
 
-        /*
-         * at least one page was bounced, fill in possible non-highmem
-         * pages
-         */
-        __bio_for_each_segment(from, *bio_orig, i, 0) {
-                to = bio_iovec_idx(bio, i);
-                if (!to->bv_page) {
-                        to->bv_page = from->bv_page;
-                        to->bv_len = from->bv_len;
-                        to->bv_offset = from->bv_offset;
-                }
-        }
-
-        bio->bi_bdev = (*bio_orig)->bi_bdev;
         bio->bi_flags |= (1 << BIO_BOUNCED);
-        bio->bi_sector = (*bio_orig)->bi_sector;
-        bio->bi_rw = (*bio_orig)->bi_rw;
-
-        bio->bi_vcnt = (*bio_orig)->bi_vcnt;
-        bio->bi_idx = (*bio_orig)->bi_idx;
-        bio->bi_size = (*bio_orig)->bi_size;
 
         if (pool == page_pool) {
                 bio->bi_end_io = bounce_end_io_write;