From a0b81ae7a4ff8a779e9f16152563d614cb91f13c Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 11 Apr 2023 19:14:55 +0200 Subject: [PATCH] zram: refactor zram_bdev_write Split the read/modify/write case into a separate helper. Link: https://lkml.kernel.org/r/20230411171459.567614-14-hch@lst.de Signed-off-by: Christoph Hellwig Acked-by: Minchan Kim Reviewed-by: Sergey Senozhatsky Cc: Jens Axboe Signed-off-by: Andrew Morton --- drivers/block/zram/zram_drv.c | 38 +++++++++++++++++++------------------- 1 file changed, 19 insertions(+), 19 deletions(-) diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index cbcfb5c..1a7fe75 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -1568,33 +1568,33 @@ out: return ret; } -static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, - u32 index, int offset, struct bio *bio) +/* + * This is a partial IO. Read the full page before writing the changes. + */ +static int zram_bvec_write_partial(struct zram *zram, struct bio_vec *bvec, + u32 index, int offset, struct bio *bio) { - struct page *page = bvec->bv_page; + struct page *page = alloc_page(GFP_NOIO); int ret; - if (is_partial_io(bvec)) { - /* - * This is a partial IO. We need to read the full page - * before to write the changes. - */ - page = alloc_page(GFP_NOIO); - if (!page) - return -ENOMEM; - - ret = zram_read_page(zram, page, index, bio, true); - if (ret) - goto out; + if (!page) + return -ENOMEM; + ret = zram_read_page(zram, page, index, bio, true); + if (!ret) { memcpy_from_bvec(page_address(page) + offset, bvec); + ret = zram_write_page(zram, page, index); } + __free_page(page); + return ret; +} - ret = zram_write_page(zram, page, index); -out: +static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, + u32 index, int offset, struct bio *bio) +{ if (is_partial_io(bvec)) - __free_page(page); - return ret; + return zram_bvec_write_partial(zram, bvec, index, offset, bio); + return zram_write_page(zram, bvec->bv_page, index); } #ifdef CONFIG_ZRAM_MULTI_COMP -- 2.7.4