ceph: Convert to immutable biovecs

Now that we've got a mechanism for immutable biovecs -
bi_iter.bi_bvec_done - we need to convert drivers to use primitives that
respect it instead of using the bvec array directly.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Sage Weil <sage@inktank.com>
Cc: ceph-devel@vger.kernel.org

diff --git a/include/linux/ceph/messenger.h b/include/linux/ceph/messenger.h
index 7c1420b..091fdb6 100644 (file)
--- a/include/linux/ceph/messenger.h
+++ b/include/linux/ceph/messenger.h
@@ -1,6 +1,7 @@
 #ifndef __FS_CEPH_MESSENGER_H
 #define __FS_CEPH_MESSENGER_H
 
+#include <linux/blk_types.h>
 #include <linux/kref.h>
 #include <linux/mutex.h>
 #include <linux/net.h>
@@ -119,8 +120,7 @@ struct ceph_msg_data_cursor {
 #ifdef CONFIG_BLOCK
                struct {                                /* bio */
                        struct bio      *bio;           /* bio from list */
-                       unsigned int    vector_index;   /* vector from bio */
-                       unsigned int    vector_offset;  /* bytes from vector */
+                       struct bvec_iter bvec_iter;
                };
 #endif /* CONFIG_BLOCK */
                struct {                                /* pages */

diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
index 4a5df7b..18c039b 100644 (file)
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -777,13 +777,12 @@ static void ceph_msg_data_bio_cursor_init(struct ceph_msg_data_cursor *cursor,
 
        bio = data->bio;
        BUG_ON(!bio);
-       BUG_ON(!bio->bi_vcnt);
 
        cursor->resid = min(length, data->bio_length);
        cursor->bio = bio;
-       cursor->vector_index = 0;
-       cursor->vector_offset = 0;
-       cursor->last_piece = length <= bio->bi_io_vec[0].bv_len;
+       cursor->bvec_iter = bio->bi_iter;
+       cursor->last_piece =
+               cursor->resid <= bio_iter_len(bio, cursor->bvec_iter);
 }
 
 static struct page *ceph_msg_data_bio_next(struct ceph_msg_data_cursor *cursor,
@@ -792,71 +791,63 @@ static struct page *ceph_msg_data_bio_next(struct ceph_msg_data_cursor *cursor,
 {
        struct ceph_msg_data *data = cursor->data;
        struct bio *bio;
-       struct bio_vec *bio_vec;
-       unsigned int index;
+       struct bio_vec bio_vec;
 
        BUG_ON(data->type != CEPH_MSG_DATA_BIO);
 
        bio = cursor->bio;
        BUG_ON(!bio);
 
-       index = cursor->vector_index;
-       BUG_ON(index >= (unsigned int) bio->bi_vcnt);
+       bio_vec = bio_iter_iovec(bio, cursor->bvec_iter);
 
-       bio_vec = &bio->bi_io_vec[index];
-       BUG_ON(cursor->vector_offset >= bio_vec->bv_len);
-       *page_offset = (size_t) (bio_vec->bv_offset + cursor->vector_offset);
+       *page_offset = (size_t) bio_vec.bv_offset;
        BUG_ON(*page_offset >= PAGE_SIZE);
        if (cursor->last_piece) /* pagelist offset is always 0 */
                *length = cursor->resid;
        else
-               *length = (size_t) (bio_vec->bv_len - cursor->vector_offset);
+               *length = (size_t) bio_vec.bv_len;
        BUG_ON(*length > cursor->resid);
        BUG_ON(*page_offset + *length > PAGE_SIZE);
 
-       return bio_vec->bv_page;
+       return bio_vec.bv_page;
 }
 
 static bool ceph_msg_data_bio_advance(struct ceph_msg_data_cursor *cursor,
                                        size_t bytes)
 {
        struct bio *bio;
-       struct bio_vec *bio_vec;
-       unsigned int index;
+       struct bio_vec bio_vec;
 
        BUG_ON(cursor->data->type != CEPH_MSG_DATA_BIO);
 
        bio = cursor->bio;
        BUG_ON(!bio);
 
-       index = cursor->vector_index;
-       BUG_ON(index >= (unsigned int) bio->bi_vcnt);
-       bio_vec = &bio->bi_io_vec[index];
+       bio_vec = bio_iter_iovec(bio, cursor->bvec_iter);
 
        /* Advance the cursor offset */
 
        BUG_ON(cursor->resid < bytes);
        cursor->resid -= bytes;
-       cursor->vector_offset += bytes;
-       if (cursor->vector_offset < bio_vec->bv_len)
+
+       bio_advance_iter(bio, &cursor->bvec_iter, bytes);
+
+       if (bytes < bio_vec.bv_len)
                return false;   /* more bytes to process in this segment */
-       BUG_ON(cursor->vector_offset != bio_vec->bv_len);
 
        /* Move on to the next segment, and possibly the next bio */
 
-       if (++index == (unsigned int) bio->bi_vcnt) {
+       if (!cursor->bvec_iter.bi_size) {
                bio = bio->bi_next;
-               index = 0;
+               cursor->bvec_iter = bio->bi_iter;
        }
        cursor->bio = bio;
-       cursor->vector_index = index;
-       cursor->vector_offset = 0;
 
        if (!cursor->last_piece) {
                BUG_ON(!cursor->resid);
                BUG_ON(!bio);
                /* A short read is OK, so use <= rather than == */
-               if (cursor->resid <= bio->bi_io_vec[index].bv_len)
+               if (cursor->resid <= bio_iter_len(bio, cursor->bvec_iter))
                        cursor->last_piece = true;
        }