[PATCH 4.12 20/31] md: remove idx from struct resync_pages

Greg Kroah-Hartman
2017-08-03T23:18:31Z

From: Ming Lei <ming.lei@redhat.com>

commit 022e510fcbda79183fd2cdc01abb01b4be80d03f upstream.

bio_add_page() won't fail for resync bio, and the page index for each
bio is same, so remove it.

More importantly the 'idx' of 'struct resync_pages' is initialized in
mempool allocator function, the current way is wrong since mempool is
only responsible for allocation, we can't use that for initialization.

Suggested-by: NeilBrown <neilb@suse.com>
Reported-by: NeilBrown <neilb@suse.com>
Reported-and-tested-by: Patrick <dto@gmx.net>
Fixes: f0250618361d(md: raid10: don't use bio's vec table to manage resync pages)
Fixes: 98d30c5812c3(md: raid1: don't use bio's vec table to manage resync pages)
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/md/md.h | 1 -
drivers/md/raid1.c | 6 +++---
drivers/md/raid10.c | 6 +++---
3 files changed, 6 insertions(+), 7 deletions(-)

--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -733,7 +733,6 @@ static inline void mddev_check_write_zer

/* for managing resync I/O pages */
struct resync_pages {
- unsigned idx; /* for get/put page from the pool */
void *raid_bio;
struct page *pages[RESYNC_PAGES];
};
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -170,7 +170,6 @@ static void * r1buf_pool_alloc(gfp_t gfp
resync_get_all_pages(rp);
}

- rp->idx = 0;
rp->raid_bio = r1_bio;
bio->bi_private = rp;
}
@@ -2621,6 +2620,7 @@ static sector_t raid1_sync_request(struc
int good_sectors = RESYNC_SECTORS;
int min_bad = 0; /* number of sectors that are bad in all devices */
int idx = sector_to_idx(sector_nr);
+ int page_idx = 0;

if (!conf->r1buf_pool)
if (init_resync(conf))
@@ -2848,7 +2848,7 @@ static sector_t raid1_sync_request(struc
bio = r1_bio->bios[i];
rp = get_resync_pages(bio);
if (bio->bi_end_io) {
- page = resync_fetch_page(rp, rp->idx++);
+ page = resync_fetch_page(rp, page_idx);

/*
* won't fail because the vec table is big
@@ -2860,7 +2860,7 @@ static sector_t raid1_sync_request(struc
nr_sectors += len>>9;
sector_nr += len>>9;
sync_blocks -= (len>>9);
- } while (get_resync_pages(r1_bio->bios[disk]->bi_private)->idx < RESYNC_PAGES);
+ } while (++page_idx < RESYNC_PAGES);

r1_bio->sectors = nr_sectors;

--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -221,7 +221,6 @@ static void * r10buf_pool_alloc(gfp_t gf
resync_get_all_pages(rp);
}

- rp->idx = 0;
rp->raid_bio = r10_bio;
bio->bi_private = rp;
if (rbio) {
@@ -2853,6 +2852,7 @@ static sector_t raid10_sync_request(stru
sector_t sectors_skipped = 0;
int chunks_skipped = 0;
sector_t chunk_mask = conf->geo.chunk_mask;
+ int page_idx = 0;

if (!conf->r10buf_pool)
if (init_resync(conf))
@@ -3355,7 +3355,7 @@ static sector_t raid10_sync_request(stru
break;
for (bio= biolist ; bio ; bio=bio->bi_next) {
struct resync_pages *rp = get_resync_pages(bio);
- page = resync_fetch_page(rp, rp->idx++);
+ page = resync_fetch_page(rp, page_idx);
/*
* won't fail because the vec table is big enough
* to hold all these pages
@@ -3364,7 +3364,7 @@ static sector_t raid10_sync_request(stru
}
nr_sectors += len>>9;
sector_nr += len>>9;
- } while (get_resync_pages(biolist)->idx < RESYNC_PAGES);
+ } while (++page_idx < RESYNC_PAGES);
r10_bio->sectors = nr_sectors;

while (biolist) {