bfq: Fix bfq linkage error

[linux-2.6-block.git] / block / bio.c

diff --git a/block/bio.c b/block/bio.c
index 299a0e7651ec00336f8b41b9d515eabc7d65ac0e..8f0ed6228fc59494c6319b3f50a26ba49669a221 100644 (file)
--- a/block/bio.c
+++ b/block/bio.c
@@ -646,25 +646,20 @@ static inline bool page_is_mergeable(const struct bio_vec *bv,
        return true;
 }
 
-/*
- * Check if the @page can be added to the current segment(@bv), and make
- * sure to call it only if page_is_mergeable(@bv, @page) is true
- */
-static bool can_add_page_to_seg(struct request_queue *q,
-               struct bio_vec *bv, struct page *page, unsigned len,
-               unsigned offset)
+static bool bio_try_merge_pc_page(struct request_queue *q, struct bio *bio,
+               struct page *page, unsigned len, unsigned offset,
+               bool *same_page)
 {
+       struct bio_vec *bv = &bio->bi_io_vec[bio->bi_vcnt - 1];
        unsigned long mask = queue_segment_boundary(q);
        phys_addr_t addr1 = page_to_phys(bv->bv_page) + bv->bv_offset;
        phys_addr_t addr2 = page_to_phys(page) + offset + len - 1;
 
        if ((addr1 | mask) != (addr2 | mask))
                return false;
-
        if (bv->bv_len + len > queue_max_segment_size(q))
                return false;
-
-       return true;
+       return __bio_try_merge_page(bio, page, len, offset, same_page);
 }
 
 /**
@@ -674,7 +669,7 @@ static bool can_add_page_to_seg(struct request_queue *q,
  *     @page: page to add
  *     @len: vec entry length
  *     @offset: vec entry offset
- *     @put_same_page: put the page if it is same with last added page
+ *     @same_page: return if the merge happen inside the same page
  *
  *     Attempt to add a page to the bio_vec maplist. This can fail for a
  *     number of reasons, such as the bio being full or target block device
@@ -685,10 +680,9 @@ static bool can_add_page_to_seg(struct request_queue *q,
  */
 static int __bio_add_pc_page(struct request_queue *q, struct bio *bio,
                struct page *page, unsigned int len, unsigned int offset,
-               bool put_same_page)
+               bool *same_page)
 {
        struct bio_vec *bvec;
-       bool same_page = false;
 
        /*
         * cloned bio must not modify vec list
@@ -700,28 +694,16 @@ static int __bio_add_pc_page(struct request_queue *q, struct bio *bio,
                return 0;
 
        if (bio->bi_vcnt > 0) {
-               bvec = &bio->bi_io_vec[bio->bi_vcnt - 1];
-
-               if (page == bvec->bv_page &&
-                   offset == bvec->bv_offset + bvec->bv_len) {
-                       if (put_same_page)
-                               put_page(page);
-                       bvec->bv_len += len;
-                       goto done;
-               }
+               if (bio_try_merge_pc_page(q, bio, page, len, offset, same_page))
+                       return len;
 
                /*
-                * If the queue doesn't support SG gaps and adding this
-                * offset would create a gap, disallow it.
+                * If the queue doesn't support SG gaps and adding this segment
+                * would create a gap, disallow it.
                 */
+               bvec = &bio->bi_io_vec[bio->bi_vcnt - 1];
                if (bvec_gap_to_prev(q, bvec, offset))
                        return 0;
-
-               if (page_is_mergeable(bvec, page, len, offset, &same_page) &&
-                   can_add_page_to_seg(q, bvec, page, len, offset)) {
-                       bvec->bv_len += len;
-                       goto done;
-               }
        }
 
        if (bio_full(bio, len))
@@ -735,7 +717,6 @@ static int __bio_add_pc_page(struct request_queue *q, struct bio *bio,
        bvec->bv_len = len;
        bvec->bv_offset = offset;
        bio->bi_vcnt++;
- done:
        bio->bi_iter.bi_size += len;
        return len;
 }
@@ -743,7 +724,8 @@ static int __bio_add_pc_page(struct request_queue *q, struct bio *bio,
 int bio_add_pc_page(struct request_queue *q, struct bio *bio,
                struct page *page, unsigned int len, unsigned int offset)
 {
-       return __bio_add_pc_page(q, bio, page, len, offset, false);
+       bool same_page = false;
+       return __bio_add_pc_page(q, bio, page, len, offset, &same_page);
 }
 EXPORT_SYMBOL(bio_add_pc_page);
 
@@ -806,6 +788,9 @@ void __bio_add_page(struct bio *bio, struct page *page,
 
        bio->bi_iter.bi_size += len;
        bio->bi_vcnt++;
+
+       if (!bio_flagged(bio, BIO_WORKINGSET) && unlikely(PageWorkingset(page)))
+               bio_set_flag(bio, BIO_WORKINGSET);
 }
 EXPORT_SYMBOL_GPL(__bio_add_page);
 
@@ -1384,13 +1369,17 @@ struct bio *bio_map_user_iov(struct request_queue *q,
                        for (j = 0; j < npages; j++) {
                                struct page *page = pages[j];
                                unsigned int n = PAGE_SIZE - offs;
+                               bool same_page = false;
 
                                if (n > bytes)
                                        n = bytes;
 
                                if (!__bio_add_pc_page(q, bio, page, n, offs,
-                                                       true))
+                                               &same_page)) {
+                                       if (same_page)
+                                               put_page(page);
                                        break;
+                               }
 
                                added += n;
                                bytes -= n;
@@ -1521,7 +1510,6 @@ struct bio *bio_map_kern(struct request_queue *q, void *data, unsigned int len,
        bio->bi_end_io = bio_map_kern_endio;
        return bio;
 }
-EXPORT_SYMBOL(bio_map_kern);
 
 static void bio_copy_kern_endio(struct bio *bio)
 {
@@ -1842,8 +1830,8 @@ EXPORT_SYMBOL(bio_endio);
  * @bio, and updates @bio to represent the remaining sectors.
  *
  * Unless this is a discard request the newly allocated bio will point
- * to @bio's bi_io_vec; it is the caller's responsibility to ensure that
- * @bio is not freed before the split.
+ * to @bio's bi_io_vec. It is the caller's responsibility to ensure that
+ * neither @bio nor @bs are freed before the split bio.
  */
 struct bio *bio_split(struct bio *bio, int sectors,
                      gfp_t gfp, struct bio_set *bs)