From b293f02e1423f2099744f3ade23ddd83b65321fc Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Thu, 1 Nov 2007 19:45:34 -0400 Subject: Btrfs: Add writepages support Signed-off-by: Chris Mason --- fs/btrfs/extent_map.c | 135 ++++++++++++++++++++++++++++++++++++++++---------- 1 file changed, 110 insertions(+), 25 deletions(-) (limited to 'fs/btrfs/extent_map.c') diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c index ff8881fb56d6..b0677c84bb75 100644 --- a/fs/btrfs/extent_map.c +++ b/fs/btrfs/extent_map.c @@ -10,6 +10,7 @@ #include #include #include +#include #include "extent_map.h" /* temporary define until extent_map moves out of btrfs */ @@ -35,6 +36,12 @@ struct tree_entry { struct rb_node rb_node; }; +struct extent_page_data { + struct bio *bio; + struct extent_map_tree *tree; + get_extent_t *get_extent; +}; + void __init extent_map_init(void) { extent_map_cache = btrfs_cache_create("extent_map", @@ -1460,40 +1467,76 @@ static int end_bio_extent_preparewrite(struct bio *bio, #endif } -static int submit_extent_page(int rw, struct extent_map_tree *tree, - struct page *page, sector_t sector, - size_t size, unsigned long offset, - struct block_device *bdev, - bio_end_io_t end_io_func) +static struct bio * +extent_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs, + gfp_t gfp_flags) { struct bio *bio; - int ret = 0; - bio = bio_alloc(GFP_NOIO, 1); + bio = bio_alloc(gfp_flags, nr_vecs); - bio->bi_sector = sector; - bio->bi_bdev = bdev; - bio->bi_io_vec[0].bv_page = page; - bio->bi_io_vec[0].bv_len = size; - bio->bi_io_vec[0].bv_offset = offset; - - bio->bi_vcnt = 1; - bio->bi_idx = 0; - bio->bi_size = size; + if (bio == NULL && (current->flags & PF_MEMALLOC)) { + while (!bio && (nr_vecs /= 2)) + bio = bio_alloc(gfp_flags, nr_vecs); + } - bio->bi_end_io = end_io_func; - bio->bi_private = tree; + if (bio) { + bio->bi_bdev = bdev; + bio->bi_sector = first_sector; + } + return bio; +} +static int submit_one_bio(int rw, struct bio *bio) +{ + int ret = 0; bio_get(bio); submit_bio(rw, bio); - if (bio_flagged(bio, BIO_EOPNOTSUPP)) ret = -EOPNOTSUPP; - bio_put(bio); return ret; } +static int submit_extent_page(int rw, struct extent_map_tree *tree, + struct page *page, sector_t sector, + size_t size, unsigned long offset, + struct block_device *bdev, + struct bio **bio_ret, + int max_pages, + bio_end_io_t end_io_func) +{ + int ret = 0; + struct bio *bio; + int nr; + + if (bio_ret && *bio_ret) { + bio = *bio_ret; + if (bio->bi_sector + (bio->bi_size >> 9) != sector || + bio_add_page(bio, page, size, offset) < size) { + ret = submit_one_bio(rw, bio); + bio = NULL; + } else { + return 0; + } + } + nr = min(max_pages, bio_get_nr_vecs(bdev)); + bio = extent_bio_alloc(bdev, sector, nr, GFP_NOFS | __GFP_HIGH); + if (!bio) { + printk("failed to allocate bio nr %d\n", nr); + } + bio_add_page(bio, page, size, offset); + bio->bi_end_io = end_io_func; + bio->bi_private = tree; + if (bio_ret) { + *bio_ret = bio; + } else { + ret = submit_one_bio(rw, bio); + } + + return ret; +} + void set_page_extent_mapped(struct page *page) { if (!PagePrivate(page)) { @@ -1590,7 +1633,8 @@ int extent_read_full_page(struct extent_map_tree *tree, struct page *page, if (!ret) { ret = submit_extent_page(READ, tree, page, sector, iosize, page_offset, - bdev, end_bio_extent_readpage); + bdev, NULL, 1, + end_bio_extent_readpage); } if (ret) SetPageError(page); @@ -1613,11 +1657,12 @@ EXPORT_SYMBOL(extent_read_full_page); * are found, they are marked writeback. Then the lock bits are removed * and the end_io handler clears the writeback ranges */ -int extent_write_full_page(struct extent_map_tree *tree, struct page *page, - get_extent_t *get_extent, - struct writeback_control *wbc) +static int __extent_writepage(struct page *page, struct writeback_control *wbc, + void *data) { struct inode *inode = page->mapping->host; + struct extent_page_data *epd = data; + struct extent_map_tree *tree = epd->tree; u64 start = (u64)page->index << PAGE_CACHE_SHIFT; u64 page_end = start + PAGE_CACHE_SIZE - 1; u64 end; @@ -1691,7 +1736,7 @@ int extent_write_full_page(struct extent_map_tree *tree, struct page *page, clear_extent_dirty(tree, cur, page_end, GFP_NOFS); break; } - em = get_extent(inode, page, page_offset, cur, end, 1); + em = epd->get_extent(inode, page, page_offset, cur, end, 1); if (IS_ERR(em) || !em) { SetPageError(page); break; @@ -1734,9 +1779,12 @@ int extent_write_full_page(struct extent_map_tree *tree, struct page *page, if (ret) SetPageError(page); else { + unsigned long nr = end_index + 1; set_range_writeback(tree, cur, cur + iosize - 1); + ret = submit_extent_page(WRITE, tree, page, sector, iosize, page_offset, bdev, + &epd->bio, nr, end_bio_extent_writepage); if (ret) SetPageError(page); @@ -1750,8 +1798,44 @@ done: unlock_page(page); return 0; } + +int extent_write_full_page(struct extent_map_tree *tree, struct page *page, + get_extent_t *get_extent, + struct writeback_control *wbc) +{ + int ret; + struct extent_page_data epd = { + .bio = NULL, + .tree = tree, + .get_extent = get_extent, + }; + + ret = __extent_writepage(page, wbc, &epd); + if (epd.bio) + submit_one_bio(WRITE, epd.bio); + return ret; +} EXPORT_SYMBOL(extent_write_full_page); +int extent_writepages(struct extent_map_tree *tree, + struct address_space *mapping, + get_extent_t *get_extent, + struct writeback_control *wbc) +{ + int ret; + struct extent_page_data epd = { + .bio = NULL, + .tree = tree, + .get_extent = get_extent, + }; + + ret = write_cache_pages(mapping, wbc, __extent_writepage, &epd); + if (epd.bio) + submit_one_bio(WRITE, epd.bio); + return ret; +} +EXPORT_SYMBOL(extent_writepages); + /* * basic invalidatepage code, this waits on any locked or writeback * ranges corresponding to the page, and then deletes any extent state @@ -1869,6 +1953,7 @@ int extent_prepare_write(struct extent_map_tree *tree, EXTENT_LOCKED, 0, NULL, GFP_NOFS); ret = submit_extent_page(READ, tree, page, sector, iosize, page_offset, em->bdev, + NULL, 1, end_bio_extent_preparewrite); iocount++; block_start = block_start + iosize; -- cgit v1.2.3