Message ID | 20190901055130.30572-14-hsiangkao@aol.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | erofs: patchset addressing Christoph's comments | expand |
On Sun, Sep 01, 2019 at 01:51:22PM +0800, Gao Xiang wrote: > From: Gao Xiang <gaoxiang25@huawei.com> > > As Christoph pointed out [1], "erofs_grab_bio tries to > handle a bio_alloc failure, except that the function will > not actually fail due the mempool backing it." > > Sorry about useless code, fix it now. A lot of file systems used to have this, it is a classic that gets copy and pasted everywhere. If you feel like doing a little project it might make sense to check for other places that do the same. > + bio = erofs_grab_bio(sb, blkaddr, 1, sb, read_endio); > > if (bio_add_page(bio, page, PAGE_SIZE, 0) != PAGE_SIZE) { > err = -EFAULT; > @@ -275,13 +270,7 @@ static inline struct bio *erofs_read_raw_page(struct bio *bio, > if (nblocks > BIO_MAX_PAGES) > nblocks = BIO_MAX_PAGES; > > - bio = erofs_grab_bio(sb, blknr, nblocks, sb, > - read_endio, false); > - if (IS_ERR(bio)) { > - err = PTR_ERR(bio); > - bio = NULL; > - goto err_out; > - } > + bio = erofs_grab_bio(sb, blknr, nblocks, sb, read_endio); Btw, I think you should remove erofs_grab_bio in its current form. The full code in data.c is indeed used in two places, so a local erofs_raw_page_alloc_bio (or whatever name you prefer) helper here that hardcodes the sb amd read_endio argument to simplify it a bit makes sense. > diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c > index f06a2fad7af2..abe28565d6c0 100644 > --- a/fs/erofs/zdata.c > +++ b/fs/erofs/zdata.c > @@ -1265,7 +1265,7 @@ static bool z_erofs_vle_submit_all(struct super_block *sb, > if (!bio) { > bio = erofs_grab_bio(sb, first_index + i, > BIO_MAX_PAGES, bi_private, > - z_erofs_vle_read_endio, true); > + z_erofs_vle_read_endio); But I think here you might as well open code it entirely, or at least us a separate (and local to zdata.c) helper.
diff --git a/fs/erofs/data.c b/fs/erofs/data.c index e2e40ec2bfd1..621954d4fb09 100644 --- a/fs/erofs/data.c +++ b/fs/erofs/data.c @@ -62,12 +62,7 @@ struct page *__erofs_get_meta_page(struct super_block *sb, if (!PageUptodate(page)) { struct bio *bio; - bio = erofs_grab_bio(sb, blkaddr, 1, sb, read_endio, nofail); - if (IS_ERR(bio)) { - DBG_BUGON(nofail); - err = PTR_ERR(bio); - goto err_out; - } + bio = erofs_grab_bio(sb, blkaddr, 1, sb, read_endio); if (bio_add_page(bio, page, PAGE_SIZE, 0) != PAGE_SIZE) { err = -EFAULT; @@ -275,13 +270,7 @@ static inline struct bio *erofs_read_raw_page(struct bio *bio, if (nblocks > BIO_MAX_PAGES) nblocks = BIO_MAX_PAGES; - bio = erofs_grab_bio(sb, blknr, nblocks, sb, - read_endio, false); - if (IS_ERR(bio)) { - err = PTR_ERR(bio); - bio = NULL; - goto err_out; - } + bio = erofs_grab_bio(sb, blknr, nblocks, sb, read_endio); } err = bio_add_page(bio, page, PAGE_SIZE, 0); diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h index 6bd82a82b11f..01749be24f3d 100644 --- a/fs/erofs/internal.h +++ b/fs/erofs/internal.h @@ -410,24 +410,9 @@ static inline int z_erofs_map_blocks_iter(struct inode *inode, static inline struct bio *erofs_grab_bio(struct super_block *sb, erofs_blk_t blkaddr, unsigned int nr_pages, - void *bi_private, bio_end_io_t endio, - bool nofail) + void *bi_private, bio_end_io_t endio) { - const gfp_t gfp = GFP_NOIO; - struct bio *bio; - - do { - if (nr_pages == 1) { - bio = bio_alloc(gfp | (nofail ? __GFP_NOFAIL : 0), 1); - if (!bio) { - DBG_BUGON(nofail); - return ERR_PTR(-ENOMEM); - } - break; - } - bio = bio_alloc(gfp, nr_pages); - nr_pages /= 2; - } while (!bio); + struct bio *bio = bio_alloc(GFP_NOIO, nr_pages); bio->bi_end_io = endio; bio_set_dev(bio, sb->s_bdev); diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c index f06a2fad7af2..abe28565d6c0 100644 --- a/fs/erofs/zdata.c +++ b/fs/erofs/zdata.c @@ -1265,7 +1265,7 @@ static bool z_erofs_vle_submit_all(struct super_block *sb, if (!bio) { bio = erofs_grab_bio(sb, first_index + i, BIO_MAX_PAGES, bi_private, - z_erofs_vle_read_endio, true); + z_erofs_vle_read_endio); ++nr_bios; }