diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index a38f32427826..d279ea8c4661 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -2138,6 +2138,80 @@ void ext4_ext_release(struct super_block *sb) #endif } +static void bi_complete(struct bio *bio, int error) +{ + complete((struct completion *)bio->bi_private); +} + +/* FIXME!! we need to try to merge to left or right after zero-out */ +static int ext4_ext_zeroout(struct inode *inode, struct ext4_extent *ex) +{ + int ret = -EIO; + struct bio *bio; + int blkbits, blocksize; + sector_t ee_pblock; + struct completion event; + unsigned int ee_len, len, done, offset; + + + blkbits = inode->i_blkbits; + blocksize = inode->i_sb->s_blocksize; + ee_len = ext4_ext_get_actual_len(ex); + ee_pblock = ext_pblock(ex); + + /* convert ee_pblock to 512 byte sectors */ + ee_pblock = ee_pblock << (blkbits - 9); + + while (ee_len > 0) { + + if (ee_len > BIO_MAX_PAGES) + len = BIO_MAX_PAGES; + else + len = ee_len; + + bio = bio_alloc(GFP_NOIO, len); + if (!bio) + return -ENOMEM; + bio->bi_sector = ee_pblock; + bio->bi_bdev = inode->i_sb->s_bdev; + + done = 0; + offset = 0; + while (done < len) { + ret = bio_add_page(bio, ZERO_PAGE(0), + blocksize, offset); + if (ret != blocksize) { + /* + * We can't add any more pages because of + * hardware limitations. Start a new bio. + */ + break; + } + done++; + offset += blocksize; + if (offset >= PAGE_CACHE_SIZE) + offset = 0; + } + + init_completion(&event); + bio->bi_private = &event; + bio->bi_end_io = bi_complete; + submit_bio(WRITE, bio); + wait_for_completion(&event); + + if (test_bit(BIO_UPTODATE, &bio->bi_flags)) + ret = 0; + else { + ret = -EIO; + break; + } + bio_put(bio); + ee_len -= done; + ee_pblock += done << (blkbits - 9); + } + return ret; +} + /* * This function is called by ext4_ext_get_blocks() if someone tries to write * to an uninitialized extent. It may result in splitting the uninitialized @@ -2204,14 +2278,19 @@ static int ext4_ext_convert_to_initialized(handle_t *handle, ex3->ee_len = cpu_to_le16(allocated - max_blocks); ext4_ext_mark_uninitialized(ex3); err = ext4_ext_insert_extent(handle, inode, path, ex3); - if (err) { + if (err == -ENOSPC) { + err = ext4_ext_zeroout(inode, &orig_ex); + if (err) + goto fix_extent_len; + /* update the extent length and mark as initialized */ ex->ee_block = orig_ex.ee_block; ex->ee_len = orig_ex.ee_len; ext4_ext_store_pblock(ex, ext_pblock(&orig_ex)); - ext4_ext_mark_uninitialized(ex); ext4_ext_dirty(handle, inode, path + depth); - goto out; - } + return le16_to_cpu(ex->ee_len); + + } else if (err) + goto fix_extent_len; /* * The depth, and hence eh & ex might change * as part of the insert above. @@ -2297,15 +2376,28 @@ static int ext4_ext_convert_to_initialized(handle_t *handle, goto out; insert: err = ext4_ext_insert_extent(handle, inode, path, &newex); - if (err) { + if (err == -ENOSPC) { + err = ext4_ext_zeroout(inode, &orig_ex); + if (err) + goto fix_extent_len; + /* update the extent length and mark as initialized */ ex->ee_block = orig_ex.ee_block; ex->ee_len = orig_ex.ee_len; ext4_ext_store_pblock(ex, ext_pblock(&orig_ex)); - ext4_ext_mark_uninitialized(ex); ext4_ext_dirty(handle, inode, path + depth); - } + return le16_to_cpu(ex->ee_len); + } else if (err) + goto fix_extent_len; out: return err ? err : allocated; + +fix_extent_len: + ex->ee_block = orig_ex.ee_block; + ex->ee_len = orig_ex.ee_len; + ext4_ext_store_pblock(ex, ext_pblock(&orig_ex)); + ext4_ext_mark_uninitialized(ex); + ext4_ext_dirty(handle, inode, path + depth); + return err; } /*