Commit f16acaf3 authored by Yufen Yu's avatar Yufen Yu Committed by Song Liu
Browse files

md/raid5: resize stripe_head when reshape array 



When reshape array, we try to reuse shared pages of old stripe_head,
and allocate more for the new one if needed.

Signed-off-by: default avatarYufen Yu <yuyufen@huawei.com>
Signed-off-by: default avatarSong Liu <songliubraving@fb.com>
parent 046169f0

drivers/md/raid5.c

+24 −0
Original line number Diff line number Diff line
@@ -2535,6 +2535,12 @@ static int resize_stripes(struct r5conf *conf, int newsize) 
		osh = get_free_stripe(conf, hash);

		unlock_device_hash_lock(conf, hash);



#if PAGE_SIZE != DEFAULT_STRIPE_SIZE

	for (i = 0; i < osh->nr_pages; i++) {

		nsh->pages[i] = osh->pages[i];

		osh->pages[i] = NULL;

	}

#endif

		for(i=0; i<conf->pool_size; i++) {

			nsh->dev[i].page = osh->dev[i].page;

			nsh->dev[i].orig_page = osh->dev[i].page;
@@ -2589,6 +2595,23 @@ static int resize_stripes(struct r5conf *conf, int newsize) 
		nsh = list_entry(newstripes.next, struct stripe_head, lru);

		list_del_init(&nsh->lru);



#if PAGE_SIZE != DEFAULT_STRIPE_SIZE

		for (i = 0; i < nsh->nr_pages; i++) {

			if (nsh->pages[i])

				continue;

			nsh->pages[i] = alloc_page(GFP_NOIO);

			if (!nsh->pages[i])

				err = -ENOMEM;

		}



		for (i = conf->raid_disks; i < newsize; i++) {

			if (nsh->dev[i].page)

				continue;

			nsh->dev[i].page = raid5_get_dev_page(nsh, i);

			nsh->dev[i].orig_page = nsh->dev[i].page;

			nsh->dev[i].offset = raid5_get_page_offset(nsh, i);

		}

#else

		for (i=conf->raid_disks; i < newsize; i++)

			if (nsh->dev[i].page == NULL) {

				struct page *p = alloc_page(GFP_NOIO);
@@ -2598,6 +2621,7 @@ static int resize_stripes(struct r5conf *conf, int newsize) 
				if (!p)

					err = -ENOMEM;

			}

#endif

		raid5_release_stripe(nsh);

	}

	/* critical section pass, GFP_NOIO no longer needed */

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