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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>
hifive-unleashed-5.1
Jens Axboe 2008-08-15 10:56:11 +02:00
parent 960e739d9e
commit 5b99c2ffa9
2 changed files with 7 additions and 7 deletions
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12
drivers/md/raid5.c
View File

@ -102,17 +102,17 @@ const char raid6_empty_zero_page[PAGE_SIZE] __attribute__((aligned(256)));
#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 @@ static inline int raid5_dec_bi_hw_segments(struct bio *bio)
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)

2
include/linux/bio.h
View File

@ -75,7 +75,7 @@ struct bio {
/* 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 */