Allocates extra data (an 'unsigned int') for bio reference accounting.
Don't need to abuse bio->bi_phys_segments.
Signed-off-by: Shaohua Li <shli@xxxxxx>
---
drivers/md/raid10.c | 40 ++++++++++++++++++++++++----------------
1 file changed, 24 insertions(+), 16 deletions(-)
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 1920756..77623ff 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -133,6 +133,12 @@ static void r10bio_pool_free(void *r10_bio, void *data)
/* maximum number of concurrent requests, memory permitting */
#define RESYNC_DEPTH (32*1024*1024/RESYNC_BLOCK_SIZE)
+/* The bio has a counter attached */
+static unsigned int *raid10_bio_ref_ptr(struct bio *bio)
+{
+ return md_get_per_bio_data(bio);
+}
+
/*
* When performing a resync, we need to read and compare, so
* we need as many pages are there are copies.
@@ -304,11 +310,11 @@ static void raid_end_bio_io(struct r10bio *r10_bio)
int done;
struct r10conf *conf = r10_bio->mddev->private;
- if (bio->bi_phys_segments) {
+ if (*raid10_bio_ref_ptr(bio)) {
unsigned long flags;
spin_lock_irqsave(&conf->device_lock, flags);
- bio->bi_phys_segments--;
- done = (bio->bi_phys_segments == 0);
+ (*raid10_bio_ref_ptr(bio))--;
+ done = (*raid10_bio_ref_ptr(bio) == 0);
spin_unlock_irqrestore(&conf->device_lock, flags);
} else
done = 1;
@@ -1162,10 +1168,10 @@ static void raid10_read_request(struct mddev *mddev, struct bio *bio,
- bio->bi_iter.bi_sector);
r10_bio->sectors = max_sectors;
spin_lock_irq(&conf->device_lock);
- if (bio->bi_phys_segments == 0)
- bio->bi_phys_segments = 2;
+ if (*raid10_bio_ref_ptr(bio) == 0)
+ *raid10_bio_ref_ptr(bio) = 2;
else
- bio->bi_phys_segments++;
+ (*raid10_bio_ref_ptr(bio))++;
spin_unlock_irq(&conf->device_lock);
/*
* Cannot call generic_make_request directly as that will be
@@ -1262,7 +1268,7 @@ static void raid10_write_request(struct mddev *mddev, struct bio *bio,
* writing to those blocks. This potentially requires several
* writes to write around the bad blocks. Each set of writes
* gets its own r10_bio with a set of bios attached. The number
- * of r10_bios is recored in bio->bi_phys_segments just as with
+ * of r10_bios is recored in a counter just as with
* the read case.
*/
@@ -1389,10 +1395,10 @@ static void raid10_write_request(struct mddev *mddev, struct bio *bio,
*/
r10_bio->sectors = max_sectors;
spin_lock_irq(&conf->device_lock);
- if (bio->bi_phys_segments == 0)
- bio->bi_phys_segments = 2;
+ if (*raid10_bio_ref_ptr(bio) == 0)
+ *raid10_bio_ref_ptr(bio) = 2;
else
- bio->bi_phys_segments++;
+ (*raid10_bio_ref_ptr(bio))++;
spin_unlock_irq(&conf->device_lock);
}
sectors_handled = r10_bio->sector + max_sectors -
@@ -1493,7 +1499,7 @@ static void raid10_write_request(struct mddev *mddev, struct bio *bio,
if (sectors_handled < bio_sectors(bio)) {
one_write_done(r10_bio);
/* We need another r10_bio. It has already been counted
- * in bio->bi_phys_segments.
+ * in bio's counter.
*/
r10_bio = mempool_alloc(conf->r10bio_pool, GFP_NOIO);
@@ -1525,11 +1531,11 @@ static void __make_request(struct mddev *mddev, struct bio *bio)
/*
* We might need to issue multiple reads to different devices if there
* are bad blocks around, so we keep track of the number of reads in
- * bio->bi_phys_segments. If this is 0, there is only one r10_bio and
+ * a counter. If this is 0, there is only one r10_bio and
* no locking will be needed when the request completes. If it is
* non-zero, then it is the number of not-completed requests.
*/
- bio->bi_phys_segments = 0;
+ *raid10_bio_ref_ptr(bio) = 0;
bio_clear_flag(bio, BIO_SEG_VALID);
if (bio_data_dir(bio) == READ)
@@ -1567,6 +1573,7 @@ static void raid10_make_request(struct mddev *mddev, struct bio *bio)
(chunk_sects - 1)),
GFP_NOIO, fs_bio_set);
bio_chain(split, bio);
+ md_bio_attach_data(mddev, split);
} else {
split = bio;
}
@@ -2667,10 +2674,10 @@ static void handle_read_error(struct mddev *mddev, struct r10bio *r10_bio)
- mbio->bi_iter.bi_sector;
r10_bio->sectors = max_sectors;
spin_lock_irq(&conf->device_lock);
- if (mbio->bi_phys_segments == 0)
- mbio->bi_phys_segments = 2;
+ if (*raid10_bio_ref_ptr(mbio) == 0)
+ *raid10_bio_ref_ptr(mbio) = 2;
else
- mbio->bi_phys_segments++;
+ (*raid10_bio_ref_ptr(mbio))++;
spin_unlock_irq(&conf->device_lock);
generic_make_request(bio);
@@ -4816,6 +4823,7 @@ static struct md_personality raid10_personality =
.start_reshape = raid10_start_reshape,
.finish_reshape = raid10_finish_reshape,
.congested = raid10_congested,
+ .per_bio_data_size = sizeof(unsigned int),
};
static int __init raid_init(void)
--
2.9.3
--
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