59  * A bvec like structure to present a sector inside a page.
180 			 * Even if the sector is not covered by bio, if it is  in cache_rbio_pages()
181 			 * a data sector it should still be uptodate as it is  in cache_rbio_pages()
268 	/* Also update the sector->uptodate bits. */  in steal_rbio_page()
283 	 * Thus if the first sector of the page belongs to data stripes, then  in is_data_stripe_page()
603 /* Return a sector from rbio->stripe_sectors, not from the bio list */
612 /* Grab a sector inside P stripe */
619 /* Grab a sector inside Q stripe, return NULL if not RAID6 */
860  * Get a sector pointer specified by its @stripe_nr and @sector_nr.
864  * @sector_nr:		Sector number inside the stripe,
875 	struct sector_ptr *sector;  in sector_in_rbio()  local
885 	sector = &rbio->bio_sectors[index];  in sector_in_rbio()
886 	if (sector->page || bio_list_only) {  in sector_in_rbio()
887 		/* Don't return sector without a valid page pointer */  in sector_in_rbio()
888 		if (!sector->page)  in sector_in_rbio()
889 			sector = NULL;  in sector_in_rbio()
891 		return sector;  in sector_in_rbio()
1030  * Add a single sector @sector into our list of bios for IO.
1037 			      struct sector_ptr *sector,  in rbio_add_io_sector()  argument
1056 	ASSERT(sector->page);  in rbio_add_io_sector()
1087 			ret = bio_add_page(last, sector->page, sectorsize,  in rbio_add_io_sector()
1088 					   sector->pgoff);  in rbio_add_io_sector()
1101 	__bio_add_page(bio, sector->page, sectorsize, sector->pgoff);  in rbio_add_io_sector()
1120 			struct sector_ptr *sector = &rbio->bio_sectors[index];  in index_one_bio()  local
1122 			sector->page = bvec.bv_page;  in index_one_bio()
1123 			sector->pgoff = bvec.bv_offset + bvec_offset;  in index_one_bio()
1124 			ASSERT(sector->pgoff < PAGE_SIZE);  in index_one_bio()
1189 	struct sector_ptr *sector;  in generate_pq_vertical()  local
1193 	/* First collect one sector from each data stripe */  in generate_pq_vertical()
1195 		sector = sector_in_rbio(rbio, stripe, sectornr, 0);  in generate_pq_vertical()
1196 		pointers[stripe] = kmap_local_page(sector->page) +  in generate_pq_vertical()
1197 				   sector->pgoff;  in generate_pq_vertical()
1201 	sector = rbio_pstripe_sector(rbio, sectornr);  in generate_pq_vertical()
1202 	sector->uptodate = 1;  in generate_pq_vertical()
1203 	pointers[stripe++] = kmap_local_page(sector->page) + sector->pgoff;  in generate_pq_vertical()
1210 		sector = rbio_qstripe_sector(rbio, sectornr);  in generate_pq_vertical()
1211 		sector->uptodate = 1;  in generate_pq_vertical()
1212 		pointers[stripe++] = kmap_local_page(sector->page) +  in generate_pq_vertical()
1213 				     sector->pgoff;  in generate_pq_vertical()
1229 	/* The total sector number inside the full stripe. */  in rmw_assemble_write_bios()
1237 	/* We should have at least one data sector. */  in rmw_assemble_write_bios()
1252 		struct sector_ptr *sector;  in rmw_assemble_write_bios()  local
1262 			sector = sector_in_rbio(rbio, stripe, sectornr, 1);  in rmw_assemble_write_bios()
1263 			if (!sector)  in rmw_assemble_write_bios()
1266 			sector = rbio_stripe_sector(rbio, stripe, sectornr);  in rmw_assemble_write_bios()
1269 		ret = rbio_add_io_sector(rbio, bio_list, sector, stripe,  in rmw_assemble_write_bios()
1287 		struct sector_ptr *sector;  in rmw_assemble_write_bios()  local
1312 			sector = sector_in_rbio(rbio, stripe, sectornr, 1);  in rmw_assemble_write_bios()
1313 			if (!sector)  in rmw_assemble_write_bios()
1316 			sector = rbio_stripe_sector(rbio, stripe, sectornr);  in rmw_assemble_write_bios()
1319 		ret = rbio_add_io_sector(rbio, bio_list, sector,  in rmw_assemble_write_bios()
1368  * stripe_pages[], thus we need to locate the sector.
1377 		struct sector_ptr *sector = &rbio->stripe_sectors[i];  in find_stripe_sector()  local
1379 		if (sector->page == page && sector->pgoff == pgoff)  in find_stripe_sector()
1380 			return sector;  in find_stripe_sector()
1398 		struct sector_ptr *sector;  in set_bio_pages_uptodate()  local
1403 			sector = find_stripe_sector(rbio, bvec->bv_page, pgoff);  in set_bio_pages_uptodate()
1404 			ASSERT(sector);  in set_bio_pages_uptodate()
1405 			if (sector)  in set_bio_pages_uptodate()
1406 				sector->uptodate = 1;  in set_bio_pages_uptodate()
1417 		struct sector_ptr *sector;  in get_bio_sector_nr()  local
1419 		sector = &rbio->stripe_sectors[i];  in get_bio_sector_nr()
1420 		if (sector->page == bv->bv_page && sector->pgoff == bv->bv_offset)  in get_bio_sector_nr()
1422 		sector = &rbio->bio_sectors[i];  in get_bio_sector_nr()
1423 		if (sector->page == bv->bv_page && sector->pgoff == bv->bv_offset)  in get_bio_sector_nr()
1479 			/* No csum for this sector, skip to the next sector. */  in verify_bio_data_sectors()
1682 	struct sector_ptr *sector;  in verify_one_sector()  local
1698 		sector = sector_in_rbio(rbio, stripe_nr, sector_nr, 0);  in verify_one_sector()
1700 		sector = rbio_stripe_sector(rbio, stripe_nr, sector_nr);  in verify_one_sector()
1703 	ASSERT(sector->page);  in verify_one_sector()
1708 	ret = btrfs_check_sector_csum(fs_info, sector->page, sector->pgoff,  in verify_one_sector()
1722 	struct sector_ptr *sector;  in recover_vertical()  local
1762 			sector = sector_in_rbio(rbio, stripe_nr, sector_nr, 0);  in recover_vertical()
1764 			sector = rbio_stripe_sector(rbio, stripe_nr, sector_nr);  in recover_vertical()
1766 		ASSERT(sector->page);  in recover_vertical()
1767 		pointers[stripe_nr] = kmap_local_page(sector->page) +  in recover_vertical()
1768 				   sector->pgoff;  in recover_vertical()
1848 	 * If possible, also check if the repaired sector matches its data  in recover_vertical()
1856 		sector = rbio_stripe_sector(rbio, faila, sector_nr);  in recover_vertical()
1857 		sector->uptodate = 1;  in recover_vertical()
1864 		sector = rbio_stripe_sector(rbio, failb, sector_nr);  in recover_vertical()
1865 		sector->uptodate = 1;  in recover_vertical()
1882 	 * @pointers array stores the pointer for each sector.  in recover_sectors()
1935 	 * not trust any cached sector.  in recover_rbio()
1945 		struct sector_ptr *sector;  in recover_rbio()  local
1962 		sector = rbio_stripe_sector(rbio, stripe, sectornr);  in recover_rbio()
1963 		ret = rbio_add_io_sector(rbio, &bio_list, sector, stripe,  in recover_rbio()
2152 		struct sector_ptr *sector;  in rmw_read_wait_recover()  local
2156 		sector = rbio_stripe_sector(rbio, stripe, sectornr);  in rmw_read_wait_recover()
2157 		ret = rbio_add_io_sector(rbio, &bio_list, sector,  in rmw_read_wait_recover()
2205  * To determine if we need to read any sector from the disk.
2213 		struct sector_ptr *sector = &rbio->stripe_sectors[i];  in need_read_stripe_sectors()  local
2216 		 * We have a sector which doesn't have page nor uptodate,  in need_read_stripe_sectors()
2220 		if (!sector->page || !sector->uptodate)  in need_read_stripe_sectors()
2241 	 * Either full stripe write, or we have every data sector already  in rmw_rbio()
2466 		struct sector_ptr *sector;  in finish_parity_scrub()  local
2471 			sector = sector_in_rbio(rbio, stripe, sectornr, 0);  in finish_parity_scrub()
2472 			pointers[stripe] = kmap_local_page(sector->page) +  in finish_parity_scrub()
2473 					   sector->pgoff;  in finish_parity_scrub()
2487 		sector = rbio_stripe_sector(rbio, rbio->scrubp, sectornr);  in finish_parity_scrub()
2488 		parity = kmap_local_page(sector->page) + sector->pgoff;  in finish_parity_scrub()
2515 		struct sector_ptr *sector;  in finish_parity_scrub()  local
2517 		sector = rbio_stripe_sector(rbio, rbio->scrubp, sectornr);  in finish_parity_scrub()
2518 		ret = rbio_add_io_sector(rbio, &bio_list, sector, rbio->scrubp,  in finish_parity_scrub()
2533 		struct sector_ptr *sector;  in finish_parity_scrub()  local
2535 		sector = rbio_stripe_sector(rbio, rbio->scrubp, sectornr);  in finish_parity_scrub()
2536 		ret = rbio_add_io_sector(rbio, &bio_list, sector,  in finish_parity_scrub()
2567 	 * @pointers array stores the pointer for each sector.  in recover_scrub_rbio()
2654 		struct sector_ptr *sector;  in scrub_assemble_read_bios()  local
2662 		 * read them from the disk. If sector_in_rbio() finds a sector  in scrub_assemble_read_bios()
2665 		sector = sector_in_rbio(rbio, stripe, sectornr, 1);  in scrub_assemble_read_bios()
2666 		if (sector)  in scrub_assemble_read_bios()
2669 		sector = rbio_stripe_sector(rbio, stripe, sectornr);  in scrub_assemble_read_bios()
2671 		 * The bio cache may have handed us an uptodate sector.  If so,  in scrub_assemble_read_bios()
2674 		if (sector->uptodate)  in scrub_assemble_read_bios()
2677 		ret = rbio_add_io_sector(rbio, &bio_list, sector, stripe,  in scrub_assemble_read_bios()
2710 	 * We have every sector properly prepared. Can finish the scrub  in scrub_rbio()