On Tue, Dec 31, 2002 at 11:22:28AM -0500, Kevin Corry wrote: > > > > On Fri, Dec 27, 2002 at 04:55:31PM -0500, Kevin Corry wrote: > > > Check memory allocations when cloning bio's. > > > > Rejected, clone_bio() cannot fail since it's allocating from a mempool > > with __GFP_WAIT set. > > > > - Joe > > Hmm. Yep. I must have mistaken GFP_NOIO for GFP_ATOMIC. > > But based on that reasoning, shouldn't the bio_alloc() call > in split_bvec() always return a valid bio, and hence make the > checks in split_bvec() and __clone_and_map() unnecessary? y, I was mistakenly under the impression that bio_alloc could fail during the allocation of the bvec. I'll add the following patch. - Joe --- diff/drivers/md/dm.c 2002-12-30 11:40:30.000000000 +0000 +++ source/drivers/md/dm.c 2003-01-02 09:51:07.000000000 +0000 @@ -347,18 +347,15 @@ struct bio_vec *bv = bio->bi_io_vec + idx; clone = bio_alloc(GFP_NOIO, 1); + memcpy(clone->bi_io_vec, bv, sizeof(*bv)); - if (clone) { - memcpy(clone->bi_io_vec, bv, sizeof(*bv)); - - clone->bi_sector = sector; - clone->bi_bdev = bio->bi_bdev; - clone->bi_rw = bio->bi_rw; - clone->bi_vcnt = 1; - clone->bi_size = to_bytes(len); - clone->bi_io_vec->bv_offset = offset; - clone->bi_io_vec->bv_len = clone->bi_size; - } + clone->bi_sector = sector; + clone->bi_bdev = bio->bi_bdev; + clone->bi_rw = bio->bi_rw; + clone->bi_vcnt = 1; + clone->bi_size = to_bytes(len); + clone->bi_io_vec->bv_offset = offset; + clone->bi_io_vec->bv_len = clone->bi_size; return clone; } @@ -432,11 +429,6 @@ clone = split_bvec(bio, ci->sector, ci->idx, bv->bv_offset, max); - if (!clone) { - dec_pending(ci->io, -ENOMEM); - return; - } - __map_bio(ti, clone, ci->io); ci->sector += max; @@ -446,11 +438,6 @@ len = to_sector(bv->bv_len) - max; clone = split_bvec(bio, ci->sector, ci->idx, bv->bv_offset + to_bytes(max), len); - if (!clone) { - dec_pending(ci->io, -ENOMEM); - return; - } - __map_bio(ti, clone, ci->io); ci->sector += len;