Merge branch 'for-linus' of git://git.kernel.dk/data/git/linux-2.6-block

* 'for-linus' of git://git.kernel.dk/data/git/linux-2.6-block: (63 commits)
  Fix memory leak in dm-crypt
  SPARC64: sg chaining support
  SPARC: sg chaining support
  PPC: sg chaining support
  PS3: sg chaining support
  IA64: sg chaining support
  x86-64: enable sg chaining
  x86-64: update pci-gart iommu to sg helpers
  x86-64: update nommu to sg helpers
  x86-64: update calgary iommu to sg helpers
  swiotlb: sg chaining support
  i386: enable sg chaining
  i386 dma_map_sg: convert to using sg helpers
  mmc: need to zero sglist on init
  Panic in blk_rq_map_sg() from CCISS driver
  remove sglist_len
  remove blk_queue_max_phys_segments in libata
  revert sg segment size ifdefs
  Fixup u14-34f ENABLE_SG_CHAINING
  qla1280: enable use_sg_chaining option
  ...

1 files changed, 17 insertions, 2 deletions

diff --git a/include/linux/bio.h b/include/linux/bio.h
index 089a8bc55dd4..4da441337d6e 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -176,13 +176,28 @@ struct bio {
 #define bio_offset(bio)         bio_iovec((bio))->bv_offset
 #define bio_segments(bio)       ((bio)->bi_vcnt - (bio)->bi_idx)
 #define bio_sectors(bio)        ((bio)->bi_size >> 9)
-#define bio_cur_sectors(bio)    (bio_iovec(bio)->bv_len >> 9)
-#define bio_data(bio)           (page_address(bio_page((bio))) + bio_offset((bio)))
 #define bio_barrier(bio)        ((bio)->bi_rw & (1 << BIO_RW_BARRIER))
 #define bio_sync(bio)           ((bio)->bi_rw & (1 << BIO_RW_SYNC))
 #define bio_failfast(bio)       ((bio)->bi_rw & (1 << BIO_RW_FAILFAST))
 #define bio_rw_ahead(bio)       ((bio)->bi_rw & (1 << BIO_RW_AHEAD))
 #define bio_rw_meta(bio)        ((bio)->bi_rw & (1 << BIO_RW_META))
+#define bio_empty_barrier(bio)  (bio_barrier(bio) && !(bio)->bi_size)
+
+static inline unsigned int bio_cur_sectors(struct bio *bio)
+{
+        if (bio->bi_vcnt)
+                return bio_iovec(bio)->bv_len >> 9;
+
+        return 0;
+}
+
+static inline void *bio_data(struct bio *bio)
+{
+        if (bio->bi_vcnt)
+                return page_address(bio_page(bio)) + bio_offset(bio);
+
+        return NULL;
+}
 
 /*
  * will die