Commit 1145059a authored by Qu Wenruo's avatar Qu Wenruo Committed by David Sterba
Browse files

btrfs: raid56: make finish_rmw() subpage compatible 



With this function converted to subpage compatible sector interfaces,
the following helper functions can be removed:

- rbio_stripe_page()
- rbio_pstripe_page()
- rbio_qstripe_page()
- page_in_rbio()

Signed-off-by: default avatarQu Wenruo <wqu@suse.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 07e4d380

fs/btrfs/raid56.c

+32 −77
Original line number Diff line number Diff line
@@ -685,39 +685,25 @@ static struct sector_ptr *rbio_stripe_sector(const struct btrfs_raid_bio *rbio, 
							      sector_nr)];

}



static int rbio_stripe_page_index(struct btrfs_raid_bio *rbio, int stripe,

				  int index)

/* Grab a sector inside P stripe */

static struct sector_ptr *rbio_pstripe_sector(const struct btrfs_raid_bio *rbio,

					      unsigned int sector_nr)

{

	return stripe * rbio->stripe_npages + index;

	return rbio_stripe_sector(rbio, rbio->nr_data, sector_nr);

}



/*

 * these are just the pages from the rbio array, not from anything

 * the FS sent down to us

 */

static struct page *rbio_stripe_page(struct btrfs_raid_bio *rbio, int stripe,

				     int index)

/* Grab a sector inside Q stripe, return NULL if not RAID6 */

static struct sector_ptr *rbio_qstripe_sector(const struct btrfs_raid_bio *rbio,

					      unsigned int sector_nr)

{

	return rbio->stripe_pages[rbio_stripe_page_index(rbio, stripe, index)];

	if (rbio->nr_data + 1 == rbio->real_stripes)

		return NULL;

	return rbio_stripe_sector(rbio, rbio->nr_data + 1, sector_nr);

}



/*

 * helper to index into the pstripe

 */

static struct page *rbio_pstripe_page(struct btrfs_raid_bio *rbio, int index)

static int rbio_stripe_page_index(struct btrfs_raid_bio *rbio, int stripe, int index)

{

	return rbio_stripe_page(rbio, rbio->nr_data, index);

}



/*

 * helper to index into the qstripe, returns null

 * if there is no qstripe

 */

static struct page *rbio_qstripe_page(struct btrfs_raid_bio *rbio, int index)

{

	if (rbio->nr_data + 1 == rbio->real_stripes)

		return NULL;

	return rbio_stripe_page(rbio, rbio->nr_data + 1, index);

	return stripe * rbio->stripe_npages + index;

}



/*
@@ -1035,40 +1021,6 @@ static struct sector_ptr *sector_in_rbio(struct btrfs_raid_bio *rbio, 
	return &rbio->stripe_sectors[index];

}



/*

 * the read/modify/write code wants to use the original bio for

 * any pages it included, and then use the rbio for everything

 * else.  This function decides if a given index (stripe number)

 * and page number in that stripe fall inside the original bio

 * or the rbio.

 *

 * if you set bio_list_only, you'll get a NULL back for any ranges

 * that are outside the bio_list

 *

 * This doesn't take any refs on anything, you get a bare page pointer

 * and the caller must bump refs as required.

 *

 * You must call index_rbio_pages once before you can trust

 * the answers from this function.

 */

static struct page *page_in_rbio(struct btrfs_raid_bio *rbio,

				 int index, int pagenr, int bio_list_only)

{

	int chunk_page;

	struct page *p = NULL;



	chunk_page = index * (rbio->stripe_len >> PAGE_SHIFT) + pagenr;



	spin_lock_irq(&rbio->bio_list_lock);

	p = rbio->bio_pages[chunk_page];

	spin_unlock_irq(&rbio->bio_list_lock);



	if (p || bio_list_only)

		return p;



	return rbio->stripe_pages[chunk_page];

}



/*

 * allocation and initial setup for the btrfs_raid_bio.  Not

 * this does not allocate any pages for rbio->pages.
@@ -1336,6 +1288,7 @@ static void index_rbio_pages(struct btrfs_raid_bio *rbio) 
static noinline void finish_rmw(struct btrfs_raid_bio *rbio)

{

	struct btrfs_io_context *bioc = rbio->bioc;

	const u32 sectorsize = bioc->fs_info->sectorsize;

	void **pointers = rbio->finish_pointers;

	int nr_data = rbio->nr_data;

	int stripe;
@@ -1384,34 +1337,36 @@ static noinline void finish_rmw(struct btrfs_raid_bio *rbio) 
		clear_bit(RBIO_CACHE_READY_BIT, &rbio->flags);



	for (sectornr = 0; sectornr < rbio->stripe_nsectors; sectornr++) {

		struct page *p;

		/* first collect one page from each data stripe */

		struct sector_ptr *sector;



		/* First collect one sector from each data stripe */

		for (stripe = 0; stripe < nr_data; stripe++) {

			p = page_in_rbio(rbio, stripe, sectornr, 0);

			pointers[stripe] = kmap_local_page(p);

			sector = sector_in_rbio(rbio, stripe, sectornr, 0);

			pointers[stripe] = kmap_local_page(sector->page) +

					   sector->pgoff;

		}



		/* then add the parity stripe */

		p = rbio_pstripe_page(rbio, sectornr);

		SetPageUptodate(p);

		pointers[stripe++] = kmap_local_page(p);

		/* Then add the parity stripe */

		sector = rbio_pstripe_sector(rbio, sectornr);

		sector->uptodate = 1;

		pointers[stripe++] = kmap_local_page(sector->page) + sector->pgoff;



		if (has_qstripe) {



			/*

			 * raid6, add the qstripe and call the

			 * library function to fill in our p/q

			 * RAID6, add the qstripe and call the library function

			 * to fill in our p/q

			 */

			p = rbio_qstripe_page(rbio, sectornr);

			SetPageUptodate(p);

			pointers[stripe++] = kmap_local_page(p);

			sector = rbio_qstripe_sector(rbio, sectornr);

			sector->uptodate = 1;

			pointers[stripe++] = kmap_local_page(sector->page) +

					     sector->pgoff;



			raid6_call.gen_syndrome(rbio->real_stripes, PAGE_SIZE,

			raid6_call.gen_syndrome(rbio->real_stripes, sectorsize,

						pointers);

		} else {

			/* raid5 */

			copy_page(pointers[nr_data], pointers[0]);

			run_xor(pointers + 1, nr_data - 1, PAGE_SIZE);

			memcpy(pointers[nr_data], pointers[0], sectorsize);

			run_xor(pointers + 1, nr_data - 1, sectorsize);

		}

		for (stripe = stripe - 1; stripe >= 0; stripe--)

			kunmap_local(pointers[stripe]);