diff options
| -rw-r--r-- | fs/jfs/inode.c | 3 | ||||
| -rw-r--r-- | fs/mpage.c | 104 | ||||
| -rw-r--r-- | fs/xfs/linux-2.6/xfs_aops.c | 5 |
3 files changed, 90 insertions, 22 deletions
diff --git a/fs/jfs/inode.c b/fs/jfs/inode.c index 51a5fed..7239ef3 100644 --- a/fs/jfs/inode.c +++ b/fs/jfs/inode.c @@ -258,7 +258,8 @@ jfs_get_blocks(struct inode *ip, sector_t lblock, unsigned long max_blocks, static int jfs_get_block(struct inode *ip, sector_t lblock, struct buffer_head *bh_result, int create) { - return jfs_get_blocks(ip, lblock, 1, bh_result, create); + return jfs_get_blocks(ip, lblock, bh_result->b_size >> ip->i_blkbits, + bh_result, create); } static int jfs_writepage(struct page *page, struct writeback_control *wbc) @@ -163,9 +163,19 @@ map_buffer_to_page(struct page *page, struct buffer_head *bh, int page_block) } while (page_bh != head); } +/* + * This is the worker routine which does all the work of mapping the disk + * blocks and constructs largest possible bios, submits them for IO if the + * blocks are not contiguous on the disk. + * + * We pass a buffer_head back and forth and use its buffer_mapped() flag to + * represent the validity of its disk mapping and to decide when to do the next + * get_block() call. + */ static struct bio * do_mpage_readpage(struct bio *bio, struct page *page, unsigned nr_pages, - sector_t *last_block_in_bio, get_block_t get_block) + sector_t *last_block_in_bio, struct buffer_head *map_bh, + unsigned long *first_logical_block, get_block_t get_block) { struct inode *inode = page->mapping->host; const unsigned blkbits = inode->i_blkbits; @@ -173,34 +183,72 @@ do_mpage_readpage(struct bio *bio, struct page *page, unsigned nr_pages, const unsigned blocksize = 1 << blkbits; sector_t block_in_file; sector_t last_block; + sector_t last_block_in_file; sector_t blocks[MAX_BUF_PER_PAGE]; unsigned page_block; unsigned first_hole = blocks_per_page; struct block_device *bdev = NULL; - struct buffer_head bh; int length; int fully_mapped = 1; + unsigned nblocks; + unsigned relative_block; if (page_has_buffers(page)) goto confused; block_in_file = (sector_t)page->index << (PAGE_CACHE_SHIFT - blkbits); - last_block = (i_size_read(inode) + blocksize - 1) >> blkbits; + last_block = block_in_file + nr_pages * blocks_per_page; + last_block_in_file = (i_size_read(inode) + blocksize - 1) >> blkbits; + if (last_block > last_block_in_file) + last_block = last_block_in_file; + page_block = 0; + + /* + * Map blocks using the result from the previous get_blocks call first. + */ + nblocks = map_bh->b_size >> blkbits; + if (buffer_mapped(map_bh) && block_in_file > *first_logical_block && + block_in_file < (*first_logical_block + nblocks)) { + unsigned map_offset = block_in_file - *first_logical_block; + unsigned last = nblocks - map_offset; + + for (relative_block = 0; ; relative_block++) { + if (relative_block == last) { + clear_buffer_mapped(map_bh); + break; + } + if (page_block == blocks_per_page) + break; + blocks[page_block] = map_bh->b_blocknr + map_offset + + relative_block; + page_block++; + block_in_file++; + } + bdev = map_bh->b_bdev; + } + + /* + * Then do more get_blocks calls until we are done with this page. + */ + map_bh->b_page = page; + while (page_block < blocks_per_page) { + map_bh->b_state = 0; + map_bh->b_size = 0; - bh.b_page = page; - for (page_block = 0; page_block < blocks_per_page; - page_block++, block_in_file++) { - bh.b_state = 0; if (block_in_file < last_block) { - bh.b_size = blocksize; - if (get_block(inode, block_in_file, &bh, 0)) + map_bh->b_size = (last_block-block_in_file) << blkbits; + if (get_block(inode, block_in_file, map_bh, 0)) goto confused; + *first_logical_block = block_in_file; } - if (!buffer_mapped(&bh)) { + if (!buffer_mapped(map_bh)) { fully_mapped = 0; if (first_hole == blocks_per_page) first_hole = page_block; + page_block++; + block_in_file++; + clear_buffer_mapped(map_bh); continue; } @@ -210,8 +258,8 @@ do_mpage_readpage(struct bio *bio, struct page *page, unsigned nr_pages, * we just collected from get_block into the page's buffers * so readpage doesn't have to repeat the get_block call */ - if (buffer_uptodate(&bh)) { - map_buffer_to_page(page, &bh, page_block); + if (buffer_uptodate(map_bh)) { + map_buffer_to_page(page, map_bh, page_block); goto confused; } @@ -219,10 +267,20 @@ do_mpage_readpage(struct bio *bio, struct page *page, unsigned nr_pages, goto confused; /* hole -> non-hole */ /* Contiguous blocks? */ - if (page_block && blocks[page_block-1] != bh.b_blocknr-1) + if (page_block && blocks[page_block-1] != map_bh->b_blocknr-1) goto confused; - blocks[page_block] = bh.b_blocknr; - bdev = bh.b_bdev; + nblocks = map_bh->b_size >> blkbits; + for (relative_block = 0; ; relative_block++) { + if (relative_block == nblocks) { + clear_buffer_mapped(map_bh); + break; + } else if (page_block == blocks_per_page) + break; + blocks[page_block] = map_bh->b_blocknr+relative_block; + page_block++; + block_in_file++; + } + bdev = map_bh->b_bdev; } if (first_hole != blocks_per_page) { @@ -261,7 +319,7 @@ alloc_new: goto alloc_new; } - if (buffer_boundary(&bh) || (first_hole != blocks_per_page)) + if (buffer_boundary(map_bh) || (first_hole != blocks_per_page)) bio = mpage_bio_submit(READ, bio); else *last_block_in_bio = blocks[blocks_per_page - 1]; @@ -332,7 +390,10 @@ mpage_readpages(struct address_space *mapping, struct list_head *pages, unsigned page_idx; sector_t last_block_in_bio = 0; struct pagevec lru_pvec; + struct buffer_head map_bh; + unsigned long first_logical_block = 0; + clear_buffer_mapped(&map_bh); pagevec_init(&lru_pvec, 0); for (page_idx = 0; page_idx < nr_pages; page_idx++) { struct page *page = list_entry(pages->prev, struct page, lru); @@ -343,7 +404,9 @@ mpage_readpages(struct address_space *mapping, struct list_head *pages, page->index, GFP_KERNEL)) { bio = do_mpage_readpage(bio, page, nr_pages - page_idx, - &last_block_in_bio, get_block); + &last_block_in_bio, &map_bh, + &first_logical_block, + get_block); if (!pagevec_add(&lru_pvec, page)) __pagevec_lru_add(&lru_pvec); } else { @@ -365,9 +428,12 @@ int mpage_readpage(struct page *page, get_block_t get_block) { struct bio *bio = NULL; sector_t last_block_in_bio = 0; + struct buffer_head map_bh; + unsigned long first_logical_block = 0; - bio = do_mpage_readpage(bio, page, 1, - &last_block_in_bio, get_block); + clear_buffer_mapped(&map_bh); + bio = do_mpage_readpage(bio, page, 1, &last_block_in_bio, + &map_bh, &first_logical_block, get_block); if (bio) mpage_bio_submit(READ, bio); return 0; diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c index 4f2476f..a79b84f 100644 --- a/fs/xfs/linux-2.6/xfs_aops.c +++ b/fs/xfs/linux-2.6/xfs_aops.c @@ -1310,8 +1310,9 @@ xfs_get_block( struct buffer_head *bh_result, int create) { - return __xfs_get_block(inode, iblock, 0, bh_result, - create, 0, BMAPI_WRITE); + return __xfs_get_block(inode, iblock, + bh_result->b_size >> inode->i_blkbits, + bh_result, create, 0, BMAPI_WRITE); } STATIC int |