From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kent Overstreet Subject: Re: [PATCH v5 04/12] pktcdvd: Switch to bio_kmalloc() Date: Wed, 8 Aug 2012 17:08:50 -0700 Message-ID: <20120809000850.GC7262@moria.home.lan> References: <1344290921-25154-1-git-send-email-koverstreet@google.com> <1344290921-25154-5-git-send-email-koverstreet@google.com> <20120808221359.GC6983@dhcp-172-17-108-109.mtv.corp.google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20120808221359.GC6983-RcKxWJ4Cfj1J2suj2OqeGauc2jM2gXBXkQQo+JxHRPFibQn6LdNjmg@public.gmane.org> Sender: linux-bcache-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Tejun Heo Cc: linux-bcache-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, dm-devel-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, axboe-tSWWG44O7X1aa/9Udqfwiw@public.gmane.org, agk-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, neilb-l3A5Bk7waGM@public.gmane.org, drbd-dev-cunTk1MwBs8qoQakbn7OcQ@public.gmane.org, vgoyal-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, mpatocka-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, sage-BnTBU8nroG7k1uMJSBkQmQ@public.gmane.org, yehuda-L5o5AL9CYN0tUFlbccrkMA@public.gmane.org, Peter Osterlund List-Id: dm-devel.ids On Wed, Aug 08, 2012 at 03:13:59PM -0700, Tejun Heo wrote: > Hello, > > On Mon, Aug 06, 2012 at 03:08:33PM -0700, Kent Overstreet wrote: > > This is prep work for killing bi_destructor - previously, pktcdvd had > > its own pkt_bio_alloc which was basically duplication bio_kmalloc(), > > necessitating its own bi_destructor implementation. > > > > v5: Un-reorder some functions, to make the patch easier to review > > > > Signed-off-by: Kent Overstreet > > Please Cc: the maintainers. Cc'ing Peter Osterlund and keeping the > whole body for him. Whoops, thanks. > Generally looks good to me. How is this tested? Untested - no hardware for it. > > Thanks. > > > --- > > drivers/block/pktcdvd.c | 67 +++++++++++----------------------------------- > > 1 files changed, 16 insertions(+), 51 deletions(-) > > > > diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c > > index ba66e44..ae55f08 100644 > > --- a/drivers/block/pktcdvd.c > > +++ b/drivers/block/pktcdvd.c > > @@ -101,6 +101,8 @@ static struct dentry *pkt_debugfs_root = NULL; /* /sys/kernel/debug/pktcdvd */ > > static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev); > > static int pkt_remove_dev(dev_t pkt_dev); > > static int pkt_seq_show(struct seq_file *m, void *p); > > +static void pkt_end_io_read(struct bio *bio, int err); > > +static void pkt_end_io_packet_write(struct bio *bio, int err); > > > > > > > > @@ -522,38 +524,6 @@ static void pkt_bio_finished(struct pktcdvd_device *pd) > > } > > } > > > > -static void pkt_bio_destructor(struct bio *bio) > > -{ > > - kfree(bio->bi_io_vec); > > - kfree(bio); > > -} > > - > > -static struct bio *pkt_bio_alloc(int nr_iovecs) > > -{ > > - struct bio_vec *bvl = NULL; > > - struct bio *bio; > > - > > - bio = kmalloc(sizeof(struct bio), GFP_KERNEL); > > - if (!bio) > > - goto no_bio; > > - bio_init(bio); > > - > > - bvl = kcalloc(nr_iovecs, sizeof(struct bio_vec), GFP_KERNEL); > > - if (!bvl) > > - goto no_bvl; > > - > > - bio->bi_max_vecs = nr_iovecs; > > - bio->bi_io_vec = bvl; > > - bio->bi_destructor = pkt_bio_destructor; > > - > > - return bio; > > - > > - no_bvl: > > - kfree(bio); > > - no_bio: > > - return NULL; > > -} > > - > > /* > > * Allocate a packet_data struct > > */ > > @@ -567,10 +537,13 @@ static struct packet_data *pkt_alloc_packet_data(int frames) > > goto no_pkt; > > > > pkt->frames = frames; > > - pkt->w_bio = pkt_bio_alloc(frames); > > + pkt->w_bio = bio_kmalloc(GFP_KERNEL, frames); > > if (!pkt->w_bio) > > goto no_bio; > > > > + pkt->w_bio->bi_end_io = pkt_end_io_packet_write; > > + pkt->w_bio->bi_private = pkt; > > + > > for (i = 0; i < frames / FRAMES_PER_PAGE; i++) { > > pkt->pages[i] = alloc_page(GFP_KERNEL|__GFP_ZERO); > > if (!pkt->pages[i]) > > @@ -581,9 +554,12 @@ static struct packet_data *pkt_alloc_packet_data(int frames) > > bio_list_init(&pkt->orig_bios); > > > > for (i = 0; i < frames; i++) { > > - struct bio *bio = pkt_bio_alloc(1); > > + struct bio *bio = bio_kmalloc(GFP_KERNEL, 1); > > if (!bio) > > goto no_rd_bio; > > + > > + bio->bi_end_io = pkt_end_io_read; > > + bio->bi_private = pkt; > > pkt->r_bios[i] = bio; > > } > > > > @@ -1111,21 +1087,15 @@ static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt) > > * Schedule reads for missing parts of the packet. > > */ > > for (f = 0; f < pkt->frames; f++) { > > - struct bio_vec *vec; > > - > > int p, offset; > > + > > if (written[f]) > > continue; > > + > > bio = pkt->r_bios[f]; > > - vec = bio->bi_io_vec; > > - bio_init(bio); > > - bio->bi_max_vecs = 1; > > - bio->bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9); > > - bio->bi_bdev = pd->bdev; > > - bio->bi_end_io = pkt_end_io_read; > > - bio->bi_private = pkt; > > - bio->bi_io_vec = vec; > > - bio->bi_destructor = pkt_bio_destructor; > > + bio_reset(bio); > > + bio->bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9); > > + bio->bi_bdev = pd->bdev; > > > > p = (f * CD_FRAMESIZE) / PAGE_SIZE; > > offset = (f * CD_FRAMESIZE) % PAGE_SIZE; > > @@ -1418,14 +1388,9 @@ static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt) > > } > > > > /* Start the write request */ > > - bio_init(pkt->w_bio); > > - pkt->w_bio->bi_max_vecs = PACKET_MAX_SIZE; > > + bio_reset(pkt->w_bio); > > pkt->w_bio->bi_sector = pkt->sector; > > pkt->w_bio->bi_bdev = pd->bdev; > > - pkt->w_bio->bi_end_io = pkt_end_io_packet_write; > > - pkt->w_bio->bi_private = pkt; > > - pkt->w_bio->bi_io_vec = bvec; > > - pkt->w_bio->bi_destructor = pkt_bio_destructor; > > for (f = 0; f < pkt->frames; f++) > > if (!bio_add_page(pkt->w_bio, bvec[f].bv_page, CD_FRAMESIZE, bvec[f].bv_offset)) > > BUG(); > > -- > > 1.7.7.3 > > > > -- > tejun