block: make bi_phys_segments an unsigned int instead of short
raid5 can overflow with more than 255 stripes, and we can increase it
to an int for free on both 32 and 64-bit archs due to the padding.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 05b2292..37e5465 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -102,17 +102,17 @@
#endif
/*
- * We maintain a biased count of active stripes in the bottom 8 bits of
- * bi_phys_segments, and a count of processed stripes in the upper 8 bits
+ * We maintain a biased count of active stripes in the bottom 16 bits of
+ * bi_phys_segments, and a count of processed stripes in the upper 16 bits
*/
static inline int raid5_bi_phys_segments(struct bio *bio)
{
- return bio->bi_phys_segments & 0xff;
+ return bio->bi_phys_segments & 0xffff;
}
static inline int raid5_bi_hw_segments(struct bio *bio)
{
- return (bio->bi_phys_segments >> 8) & 0xff;
+ return (bio->bi_phys_segments >> 16) & 0xffff;
}
static inline int raid5_dec_bi_phys_segments(struct bio *bio)
@@ -126,13 +126,13 @@
unsigned short val = raid5_bi_hw_segments(bio);
--val;
- bio->bi_phys_segments = (val << 8) | raid5_bi_phys_segments(bio);
+ bio->bi_phys_segments = (val << 16) | raid5_bi_phys_segments(bio);
return val;
}
static inline void raid5_set_bi_hw_segments(struct bio *bio, unsigned int cnt)
{
- bio->bi_phys_segments = raid5_bi_phys_segments(bio) || (cnt << 8);
+ bio->bi_phys_segments = raid5_bi_phys_segments(bio) || (cnt << 16);
}
static inline int raid6_next_disk(int disk, int raid_disks)
diff --git a/include/linux/bio.h b/include/linux/bio.h
index dfc3556..2c0c090 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -75,7 +75,7 @@
/* Number of segments in this BIO after
* physical address coalescing is performed.
*/
- unsigned short bi_phys_segments;
+ unsigned int bi_phys_segments;
unsigned int bi_size; /* residual I/O count */