From mboxrd@z Thu Jan 1 00:00:00 1970 From: Josh Durgin Subject: Re: [PATCH v2 07/16] rbd: dynamically allocate object prefix Date: Thu, 12 Jul 2012 10:42:13 -0700 Message-ID: <4FFF0C75.6050209@inktank.com> References: <4FFD847C.7070205@inktank.com> <4FFD8750.7010407@inktank.com> <4FFF083A.30903@inktank.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-yw0-f46.google.com ([209.85.213.46]:42545 "EHLO mail-yw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932285Ab2GLRmR (ORCPT ); Thu, 12 Jul 2012 13:42:17 -0400 Received: by yhmm54 with SMTP id m54so2984835yhm.19 for ; Thu, 12 Jul 2012 10:42:16 -0700 (PDT) In-Reply-To: <4FFF083A.30903@inktank.com> Sender: ceph-devel-owner@vger.kernel.org List-ID: To: Alex Elder Cc: ceph-devel@vger.kernel.org Reviewed-by: Josh Durgin On 07/12/2012 10:24 AM, Alex Elder wrote: > There is no need to impose a small limit the length of the object > prefix recorded for an rbd image in a struct rbd_image_header. > Remove the limitation by allocating space for the object prefix > dynamically. > > Signed-off-by: Alex Elder > v2: The object prefix shouldn't change when the header is refreshed. > Verify that (but still free the extra copy that gets allocated > when the header is re-read). > --- > drivers/block/rbd.c | 34 ++++++++++++++++++++++++++-------- > 1 file changed, 26 insertions(+), 8 deletions(-) > > Index: b/drivers/block/rbd.c > =================================================================== > --- a/drivers/block/rbd.c > +++ b/drivers/block/rbd.c > @@ -77,7 +77,7 @@ > */ > struct rbd_image_header { > u64 image_size; > - char object_prefix[32]; > + char *object_prefix; > __u8 obj_order; > __u8 crypt_type; > __u8 comp_type; > @@ -517,8 +517,15 @@ static int rbd_header_from_disk(struct r > header->snap_names = NULL; > header->snap_sizes = NULL; > } > + > + header->object_prefix = kmalloc(sizeof (ondisk->block_name) + 1, > + gfp_flags); > + if (!header->object_prefix) > + goto err_sizes; > + > memcpy(header->object_prefix, ondisk->block_name, > sizeof(ondisk->block_name)); > + header->object_prefix[sizeof (ondisk->block_name)] = '\0'; > > header->image_size = le64_to_cpu(ondisk->image_size); > header->obj_order = ondisk->options.order; > @@ -545,6 +552,8 @@ static int rbd_header_from_disk(struct r > > return 0; > > +err_sizes: > + kfree(header->snap_sizes); > err_names: > kfree(header->snap_names); > err_snapc: > @@ -610,9 +619,10 @@ done: > > static void rbd_header_free(struct rbd_image_header *header) > { > - kfree(header->snapc); > - kfree(header->snap_names); > + kfree(header->object_prefix); > kfree(header->snap_sizes); > + kfree(header->snap_names); > + kfree(header->snapc); > } > > /* > @@ -1710,15 +1720,20 @@ static int __rbd_refresh_header(struct r > if head moves */ > follow_seq = 1; > > - kfree(rbd_dev->header.snapc); > - kfree(rbd_dev->header.snap_names); > + /* rbd_dev->header.object_prefix shouldn't change */ > kfree(rbd_dev->header.snap_sizes); > + kfree(rbd_dev->header.snap_names); > + kfree(rbd_dev->header.snapc); > > rbd_dev->header.total_snaps = h.total_snaps; > rbd_dev->header.snapc = h.snapc; > rbd_dev->header.snap_names = h.snap_names; > rbd_dev->header.snap_names_len = h.snap_names_len; > rbd_dev->header.snap_sizes = h.snap_sizes; > + /* Free the extra copy of the object prefix */ > + WARN_ON(strcmp(rbd_dev->header.object_prefix, h.object_prefix)); > + kfree(h.object_prefix); > + > if (follow_seq) > rbd_dev->header.snapc->seq = rbd_dev->header.snapc->snaps[0]; > else > @@ -2361,10 +2376,11 @@ static int rbd_add_parse_args(struct rbd > if (!rbd_dev->pool_name) > return -ENOMEM; > > - ret = -EINVAL; > len = copy_token(&buf, rbd_dev->obj, sizeof (rbd_dev->obj)); > - if (!len || len>= sizeof (rbd_dev->obj)) > + if (!len || len>= sizeof (rbd_dev->obj)) { > + ret = -EINVAL; > goto out_err; > + } > > /* We have the object length in hand, save it. */ > > @@ -2382,8 +2398,10 @@ static int rbd_add_parse_args(struct rbd > if (!len) > memcpy(rbd_dev->snap_name, RBD_SNAP_HEAD_NAME, > sizeof (RBD_SNAP_HEAD_NAME)); > - else if (len>= sizeof (rbd_dev->snap_name)) > + else if (len>= sizeof (rbd_dev->snap_name)) { > + ret = -EINVAL; > goto out_err; > + } > > return 0; > > -- > To unsubscribe from this list: send the line "unsubscribe ceph-devel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html