--- zzzz-none-000/linux-3.10.107/fs/mpage.c 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/fs/mpage.c 2021-02-04 17:41:59.000000000 +0000 @@ -28,6 +28,7 @@ #include #include #include +#include "internal.h" /* * I/O completion handler for multipage BIOs. @@ -41,39 +42,23 @@ * status of that page is hard. See end_buffer_async_read() for the details. * There is no point in duplicating all that complexity. */ -static void mpage_end_io(struct bio *bio, int err) +static void mpage_end_io(struct bio *bio) { - const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); - struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; + struct bio_vec *bv; + int i; - do { - struct page *page = bvec->bv_page; + bio_for_each_segment_all(bv, bio, i) { + struct page *page = bv->bv_page; + page_endio(page, bio_data_dir(bio), bio->bi_error); + } - if (--bvec >= bio->bi_io_vec) - prefetchw(&bvec->bv_page->flags); - if (bio_data_dir(bio) == READ) { - if (uptodate) { - SetPageUptodate(page); - } else { - ClearPageUptodate(page); - SetPageError(page); - } - unlock_page(page); - } else { /* bio_data_dir(bio) == WRITE */ - if (!uptodate) { - SetPageError(page); - if (page->mapping) - set_bit(AS_EIO, &page->mapping->flags); - } - end_page_writeback(page); - } - } while (bvec >= bio->bi_io_vec); bio_put(bio); } static struct bio *mpage_bio_submit(int rw, struct bio *bio) { bio->bi_end_io = mpage_end_io; + guard_bio_eod(rw, bio); submit_bio(rw, bio); return NULL; } @@ -94,7 +79,7 @@ if (bio) { bio->bi_bdev = bdev; - bio->bi_sector = first_sector; + bio->bi_iter.bi_sector = first_sector; } return bio; } @@ -154,7 +139,8 @@ static struct bio * do_mpage_readpage(struct bio *bio, struct page *page, unsigned nr_pages, sector_t *last_block_in_bio, struct buffer_head *map_bh, - unsigned long *first_logical_block, get_block_t get_block) + unsigned long *first_logical_block, get_block_t get_block, + gfp_t gfp) { struct inode *inode = page->mapping->host; const unsigned blkbits = inode->i_blkbits; @@ -286,9 +272,13 @@ alloc_new: if (bio == NULL) { + if (first_hole == blocks_per_page) { + if (!bdev_read_page(bdev, blocks[0] << (blkbits - 9), + page)) + goto out; + } bio = mpage_alloc(bdev, blocks[0] << (blkbits - 9), - min_t(int, nr_pages, bio_get_nr_vecs(bdev)), - GFP_KERNEL); + min_t(int, nr_pages, BIO_MAX_PAGES), gfp); if (bio == NULL) goto confused; } @@ -371,6 +361,7 @@ sector_t last_block_in_bio = 0; struct buffer_head map_bh; unsigned long first_logical_block = 0; + gfp_t gfp = mapping_gfp_constraint(mapping, GFP_KERNEL); map_bh.b_state = 0; map_bh.b_size = 0; @@ -380,12 +371,13 @@ prefetchw(&page->flags); list_del(&page->lru); if (!add_to_page_cache_lru(page, mapping, - page->index, GFP_KERNEL)) { + page->index, + gfp)) { bio = do_mpage_readpage(bio, page, nr_pages - page_idx, &last_block_in_bio, &map_bh, &first_logical_block, - get_block); + get_block, gfp); } page_cache_release(page); } @@ -405,11 +397,12 @@ sector_t last_block_in_bio = 0; struct buffer_head map_bh; unsigned long first_logical_block = 0; + gfp_t gfp = mapping_gfp_constraint(page->mapping, GFP_KERNEL); map_bh.b_state = 0; map_bh.b_size = 0; bio = do_mpage_readpage(bio, page, 1, &last_block_in_bio, - &map_bh, &first_logical_block, get_block); + &map_bh, &first_logical_block, get_block, gfp); if (bio) mpage_bio_submit(READ, bio); return 0; @@ -440,6 +433,35 @@ unsigned use_writepage; }; +/* + * We have our BIO, so we can now mark the buffers clean. Make + * sure to only clean buffers which we know we'll be writing. + */ +static void clean_buffers(struct page *page, unsigned first_unmapped) +{ + unsigned buffer_counter = 0; + struct buffer_head *bh, *head; + if (!page_has_buffers(page)) + return; + head = page_buffers(page); + bh = head; + + do { + if (buffer_counter++ == first_unmapped) + break; + clear_buffer_dirty(bh); + bh = bh->b_this_page; + } while (bh != head); + + /* + * we cannot drop the bh if the page is not uptodate or a concurrent + * readpage would fail to serialize with the bh and it would read from + * disk before we reach the platter. + */ + if (buffer_heads_over_limit && PageUptodate(page)) + try_to_free_buffers(page); +} + static int __mpage_writepage(struct page *page, struct writeback_control *wbc, void *data) { @@ -463,6 +485,7 @@ struct buffer_head map_bh; loff_t i_size = i_size_read(inode); int ret = 0; + int wr = (wbc->sync_mode == WB_SYNC_ALL ? WRITE_SYNC : WRITE); if (page_has_buffers(page)) { struct buffer_head *head = page_buffers(page); @@ -571,14 +594,23 @@ * This page will go to BIO. Do we need to send this BIO off first? */ if (bio && mpd->last_block_in_bio != blocks[0] - 1) - bio = mpage_bio_submit(WRITE, bio); + bio = mpage_bio_submit(wr, bio); alloc_new: if (bio == NULL) { + if (first_unmapped == blocks_per_page) { + if (!bdev_write_page(bdev, blocks[0] << (blkbits - 9), + page, wbc)) { + clean_buffers(page, first_unmapped); + goto out; + } + } bio = mpage_alloc(bdev, blocks[0] << (blkbits - 9), - bio_get_nr_vecs(bdev), GFP_NOFS|__GFP_HIGH); + BIO_MAX_PAGES, GFP_NOFS|__GFP_HIGH); if (bio == NULL) goto confused; + + wbc_init_bio(wbc, bio); } /* @@ -586,42 +618,20 @@ * the confused fail path above (OOM) will be very confused when * it finds all bh marked clean (i.e. it will not write anything) */ + wbc_account_io(wbc, page, PAGE_SIZE); length = first_unmapped << blkbits; if (bio_add_page(bio, page, length, 0) < length) { - bio = mpage_bio_submit(WRITE, bio); + bio = mpage_bio_submit(wr, bio); goto alloc_new; } - /* - * OK, we have our BIO, so we can now mark the buffers clean. Make - * sure to only clean buffers which we know we'll be writing. - */ - if (page_has_buffers(page)) { - struct buffer_head *head = page_buffers(page); - struct buffer_head *bh = head; - unsigned buffer_counter = 0; - - do { - if (buffer_counter++ == first_unmapped) - break; - clear_buffer_dirty(bh); - bh = bh->b_this_page; - } while (bh != head); - - /* - * we cannot drop the bh if the page is not uptodate - * or a concurrent readpage would fail to serialize with the bh - * and it would read from disk before we reach the platter. - */ - if (buffer_heads_over_limit && PageUptodate(page)) - try_to_free_buffers(page); - } + clean_buffers(page, first_unmapped); BUG_ON(PageWriteback(page)); set_page_writeback(page); unlock_page(page); if (boundary || (first_unmapped != blocks_per_page)) { - bio = mpage_bio_submit(WRITE, bio); + bio = mpage_bio_submit(wr, bio); if (boundary_block) { write_boundary_block(boundary_bdev, boundary_block, 1 << blkbits); @@ -633,7 +643,7 @@ confused: if (bio) - bio = mpage_bio_submit(WRITE, bio); + bio = mpage_bio_submit(wr, bio); if (mpd->use_writepage) { ret = mapping->a_ops->writepage(page, wbc); @@ -689,8 +699,11 @@ }; ret = write_cache_pages(mapping, wbc, __mpage_writepage, &mpd); - if (mpd.bio) - mpage_bio_submit(WRITE, mpd.bio); + if (mpd.bio) { + int wr = (wbc->sync_mode == WB_SYNC_ALL ? + WRITE_SYNC : WRITE); + mpage_bio_submit(wr, mpd.bio); + } } blk_finish_plug(&plug); return ret; @@ -707,8 +720,11 @@ .use_writepage = 0, }; int ret = __mpage_writepage(page, wbc, &mpd); - if (mpd.bio) - mpage_bio_submit(WRITE, mpd.bio); + if (mpd.bio) { + int wr = (wbc->sync_mode == WB_SYNC_ALL ? + WRITE_SYNC : WRITE); + mpage_bio_submit(wr, mpd.bio); + } return ret; } EXPORT_SYMBOL(mpage_writepage);