Introduce rq_for_each_segment replacing rq_for_each_bio

Every usage of rq_for_each_bio wraps a usage of
bio_for_each_segment, so these can be combined into
rq_for_each_segment.

We define "struct req_iterator" to hold the 'bio' and 'index' that
are needed for the double iteration.

Signed-off-by: Neil Brown <neilb@suse.de>

Various compile fixes by me...

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

1 files changed, 38 insertions, 43 deletions

diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c
index 085b7794fb3e..f0a86e201b44 100644
--- a/drivers/block/floppy.c
+++ b/drivers/block/floppy.c
@@ -2437,22 +2437,19 @@ static void rw_interrupt(void)
 /* Compute maximal contiguous buffer size. */
 static int buffer_chain_size(void)
 {
-        struct bio *bio;
         struct bio_vec *bv;
-        int size, i;
+        int size;
+        struct req_iterator iter;
         char *base;
 
         base = bio_data(current_req->bio);
         size = 0;
 
-        rq_for_each_bio(bio, current_req) {
-                bio_for_each_segment(bv, bio, i) {
-                        if (page_address(bv->bv_page) + bv->bv_offset !=
-                            base + size)
-                                break;
+        rq_for_each_segment(bv, current_req, iter) {
+                if (page_address(bv->bv_page) + bv->bv_offset != base + size)
+                        break;
 
-                        size += bv->bv_len;
-                }
+                size += bv->bv_len;
         }
 
         return size >> 9;
@@ -2479,9 +2476,9 @@ static void copy_buffer(int ssize, int max_sector, int max_sector_2)
 {
         int remaining;          /* number of transferred 512-byte sectors */
         struct bio_vec *bv;
-        struct bio *bio;
         char *buffer, *dma_buffer;
-        int size, i;
+        int size;
+        struct req_iterator iter;
 
         max_sector = transfer_size(ssize,
                                    min(max_sector, max_sector_2),
@@ -2514,43 +2511,41 @@ static void copy_buffer(int ssize, int max_sector, int max_sector_2)
 
         size = current_req->current_nr_sectors << 9;
 
-        rq_for_each_bio(bio, current_req) {
-                bio_for_each_segment(bv, bio, i) {
-                        if (!remaining)
-                                break;
+        rq_for_each_segment(bv, current_req, iter) {
+                if (!remaining)
+                        break;
 
-                        size = bv->bv_len;
-                        SUPBOUND(size, remaining);
+                size = bv->bv_len;
+                SUPBOUND(size, remaining);
 
-                        buffer = page_address(bv->bv_page) + bv->bv_offset;
+                buffer = page_address(bv->bv_page) + bv->bv_offset;
 #ifdef FLOPPY_SANITY_CHECK
-                        if (dma_buffer + size >
-                            floppy_track_buffer + (max_buffer_sectors << 10) ||
-                            dma_buffer < floppy_track_buffer) {
-                                DPRINT("buffer overrun in copy buffer %d\n",
-                                       (int)((floppy_track_buffer -
-                                              dma_buffer) >> 9));
-                                printk("fsector_t=%d buffer_min=%d\n",
-                                       fsector_t, buffer_min);
-                                printk("current_count_sectors=%ld\n",
-                                       current_count_sectors);
-                                if (CT(COMMAND) == FD_READ)
-                                        printk("read\n");
-                                if (CT(COMMAND) == FD_WRITE)
-                                        printk("write\n");
-                                break;
-                        }
-                        if (((unsigned long)buffer) % 512)
-                                DPRINT("%p buffer not aligned\n", buffer);
-#endif
+                if (dma_buffer + size >
+                    floppy_track_buffer + (max_buffer_sectors << 10) ||
+                    dma_buffer < floppy_track_buffer) {
+                        DPRINT("buffer overrun in copy buffer %d\n",
+                               (int)((floppy_track_buffer -
+                                      dma_buffer) >> 9));
+                        printk("fsector_t=%d buffer_min=%d\n",
+                               fsector_t, buffer_min);
+                        printk("current_count_sectors=%ld\n",
+                               current_count_sectors);
                         if (CT(COMMAND) == FD_READ)
-                                memcpy(buffer, dma_buffer, size);
-                        else
-                                memcpy(dma_buffer, buffer, size);
-
-                        remaining -= size;
-                        dma_buffer += size;
+                                printk("read\n");
+                        if (CT(COMMAND) == FD_WRITE)
+                                printk("write\n");
+                        break;
                 }
+                if (((unsigned long)buffer) % 512)
+                        DPRINT("%p buffer not aligned\n", buffer);
+#endif
+                if (CT(COMMAND) == FD_READ)
+                        memcpy(buffer, dma_buffer, size);
+                else
+                        memcpy(dma_buffer, buffer, size);
+
+                remaining -= size;
+                dma_buffer += size;
         }
 #ifdef FLOPPY_SANITY_CHECK
         if (remaining) {