From: Bart Van Assche <bvanassche@acm.org>
To: Jack Wang <jinpu.wang@cloud.ionos.com>,
linux-block@vger.kernel.org, linux-rdma@vger.kernel.org
Cc: axboe@kernel.dk, hch@infradead.org, sagi@grimberg.me,
leon@kernel.org, dledford@redhat.com, jgg@ziepe.ca,
danil.kipnis@cloud.ionos.com, rpenyaev@suse.de,
pankaj.gupta@cloud.ionos.com
Subject: Re: [PATCH v11 23/26] block/rnbd: server: sysfs interface functions
Date: Sat, 28 Mar 2020 12:31:08 -0700 [thread overview]
Message-ID: <8ecc1c47-bad0-dadb-7861-8776b89f0174@acm.org> (raw)
In-Reply-To: <20200320121657.1165-24-jinpu.wang@cloud.ionos.com>
On 2020-03-20 05:16, Jack Wang wrote:
> This is the sysfs interface to rnbd mapped devices on server side:
>
> /sys/devices/virtual/rnbd-server/ctl/devices/<device_name>/
> |- block_dev
> | *** link pointing to the corresponding block device sysfs entry
> |
> |- sessions/<session-name>/
> | *** sessions directory
> |
> |- read_only
> | *** is devices mapped as read only
> |
> |- mapping_path
> *** relative device path provided by the client during mapping
>
> +static struct kobj_type ktype = {
> + .sysfs_ops = &kobj_sysfs_ops,
> +};
From Documentation/kobject.txt: "One important point cannot be
overstated: every kobject must have a release() method." I think this is
something that Greg KH feels very strongly about. Please fix this.
> +int rnbd_srv_create_dev_sysfs(struct rnbd_srv_dev *dev,
> + struct block_device *bdev,
> + const char *dir_name)
> +{
> + struct kobject *bdev_kobj;
> + int ret;
> +
> + ret = kobject_init_and_add(&dev->dev_kobj, &ktype,
> + rnbd_devs_kobj, dir_name);
> + if (ret)
> + return ret;
> +
> + ret = kobject_init_and_add(&dev->dev_sessions_kobj,
> + &ktype,
> + &dev->dev_kobj, "sessions");
> + if (ret)
> + goto err;
> +
> + bdev_kobj = &disk_to_dev(bdev->bd_disk)->kobj;
> + ret = sysfs_create_link(&dev->dev_kobj, bdev_kobj, "block_dev");
> + if (ret)
> + goto err2;
> +
> + return 0;
> +
> +err2:
> + kobject_put(&dev->dev_sessions_kobj);
> +err:
> + kobject_put(&dev->dev_kobj);
> + return ret;
> +}
Please choose more descriptive names for the goto labels, e.g.
put_sess_kobj and put_dev_kobj.
> +static ssize_t read_only_show(struct kobject *kobj, struct kobj_attribute *attr,
> + char *page)
> +{
> + struct rnbd_srv_sess_dev *sess_dev;
> +
> + sess_dev = container_of(kobj, struct rnbd_srv_sess_dev, kobj);
> +
> + return scnprintf(page, PAGE_SIZE, "%s\n",
> + (sess_dev->open_flags & FMODE_WRITE) ? "0" : "1");
> +}
The scnprintf() statement looks overcomplicated. How about the following?
return scnprintf(page, PAGE_SIZE, "%d\n",
(sess_dev->open_flags & FMODE_WRITE) != 0);
> +void rnbd_srv_destroy_dev_session_sysfs(struct rnbd_srv_sess_dev *sess_dev)
> +{
> + DECLARE_COMPLETION_ONSTACK(sysfs_compl);
> +
> + sysfs_remove_group(&sess_dev->kobj,
> + &rnbd_srv_default_dev_session_attr_group);
> +
> + sess_dev->sysfs_release_compl = &sysfs_compl;
> + kobject_del(&sess_dev->kobj);
> + kobject_put(&sess_dev->kobj);
> + wait_for_completion(&sysfs_compl);
> +}
Why is there a wait_for_completion() call in the above function? I think
Greg KH strongly disagrees with such calls in functions that remove
sysfs attributes.
> +int rnbd_srv_create_sysfs_files(void)
> +{
> + int err;
> +
> + rnbd_dev_class = class_create(THIS_MODULE, "rnbd-server");
> + if (IS_ERR(rnbd_dev_class))
> + return PTR_ERR(rnbd_dev_class);
> +
> + rnbd_dev = device_create(rnbd_dev_class, NULL,
> + MKDEV(0, 0), NULL, "ctl");
> + if (IS_ERR(rnbd_dev)) {
> + err = PTR_ERR(rnbd_dev);
> + goto cls_destroy;
> + }
> + rnbd_devs_kobj = kobject_create_and_add("devices", &rnbd_dev->kobj);
> + if (!rnbd_devs_kobj) {
> + err = -ENOMEM;
> + goto dev_destroy;
> + }
> +
> + return 0;
> +
> +dev_destroy:
> + device_destroy(rnbd_dev_class, MKDEV(0, 0));
> +cls_destroy:
> + class_destroy(rnbd_dev_class);
> +
> + return err;
> +}
Please mention the device class in the description of this patch.
Thanks,
Bart.
next prev parent reply other threads:[~2020-03-28 19:31 UTC|newest]
Thread overview: 71+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-20 12:16 [PATCH v11 00/26] RTRS (former IBTRS) RDMA Transport Library and RNBD (former IBNBD) RDMA Network Block Device Jack Wang
2020-03-20 12:16 ` [PATCH v11 01/26] sysfs: export sysfs_remove_file_self() Jack Wang
2020-03-20 12:16 ` [PATCH v11 02/26] RDMA/rtrs: public interface header to establish RDMA connections Jack Wang
2020-03-20 12:16 ` [PATCH v11 03/26] RDMA/rtrs: private headers with rtrs protocol structs and helpers Jack Wang
2020-03-20 12:16 ` [PATCH v11 04/26] RDMA/rtrs: core: lib functions shared between client and server modules Jack Wang
2020-03-28 4:26 ` Bart Van Assche
2020-03-30 10:34 ` Jinpu Wang
2020-03-30 22:25 ` Bart Van Assche
2020-03-31 7:11 ` Jinpu Wang
2020-03-20 12:16 ` [PATCH v11 05/26] RDMA/rtrs: client: private header with client structs and functions Jack Wang
2020-03-20 12:16 ` [PATCH v11 06/26] RDMA/rtrs: client: main functionality Jack Wang
2020-03-20 12:16 ` [PATCH v11 07/26] RDMA/rtrs: client: statistics functions Jack Wang
2020-03-20 12:16 ` [PATCH v11 08/26] RDMA/rtrs: client: sysfs interface functions Jack Wang
2020-03-30 22:28 ` Bart Van Assche
2020-03-31 7:20 ` Jinpu Wang
2020-03-20 12:16 ` [PATCH v11 09/26] RDMA/rtrs: server: private header with server structs and functions Jack Wang
2020-03-20 12:16 ` [PATCH v11 10/26] RDMA/rtrs: server: main functionality Jack Wang
2020-03-20 12:16 ` [PATCH v11 11/26] RDMA/rtrs: server: statistics functions Jack Wang
2020-03-20 12:16 ` [PATCH v11 12/26] RDMA/rtrs: server: sysfs interface functions Jack Wang
2020-03-30 22:29 ` Bart Van Assche
2020-03-31 7:13 ` Jinpu Wang
2020-03-20 12:16 ` [PATCH v11 13/26] RDMA/rtrs: include client and server modules into kernel compilation Jack Wang
2020-03-20 12:16 ` [PATCH v11 14/26] RDMA/rtrs: a bit of documentation Jack Wang
2020-03-20 12:16 ` [PATCH v11 15/26] block: reexport bio_map_kern Jack Wang
2020-03-28 3:58 ` Bart Van Assche
2020-03-28 8:29 ` Christoph Hellwig
2020-03-28 16:16 ` Bart Van Assche
2020-03-29 15:05 ` Christoph Hellwig
2020-03-29 18:08 ` Chaitanya Kulkarni
2020-03-30 6:28 ` hch
2020-03-30 10:44 ` Jinpu Wang
2020-03-30 18:57 ` Chaitanya Kulkarni
2020-03-20 12:16 ` [PATCH v11 16/26] block/rnbd: private headers with rnbd protocol structs and helpers Jack Wang
2020-03-28 4:58 ` Bart Van Assche
2020-03-31 7:32 ` Jinpu Wang
2020-03-20 12:16 ` [PATCH v11 17/26] block/rnbd: client: private header with client structs and functions Jack Wang
2020-03-28 4:26 ` Bart Van Assche
2020-03-31 9:08 ` Jinpu Wang
2020-03-20 12:16 ` [PATCH v11 18/26] block/rnbd: client: main functionality Jack Wang
2020-03-28 4:45 ` Bart Van Assche
2020-03-31 9:23 ` Jinpu Wang
2020-04-02 16:27 ` Jinpu Wang
2020-03-28 4:59 ` Bart Van Assche
2020-03-31 9:25 ` Jinpu Wang
2020-03-31 14:12 ` Bart Van Assche
2020-03-31 14:20 ` Jinpu Wang
2020-03-20 12:16 ` [PATCH v11 19/26] block/rnbd: client: sysfs interface functions Jack Wang
2020-03-28 4:59 ` Bart Van Assche
2020-03-31 9:26 ` Jinpu Wang
2020-03-20 12:16 ` [PATCH v11 20/26] block/rnbd: server: private header with server structs and functions Jack Wang
2020-03-20 12:16 ` [PATCH v11 21/26] block/rnbd: server: main functionality Jack Wang
2020-03-28 17:40 ` Bart Van Assche
2020-03-31 9:29 ` Jinpu Wang
2020-03-31 15:32 ` Jinpu Wang
2020-03-20 12:16 ` [PATCH v11 22/26] block/rnbd: server: functionality for IO submission to file or block dev Jack Wang
2020-03-28 18:39 ` Bart Van Assche
2020-03-31 10:06 ` Jinpu Wang
2020-03-20 12:16 ` [PATCH v11 23/26] block/rnbd: server: sysfs interface functions Jack Wang
2020-03-28 19:31 ` Bart Van Assche [this message]
2020-03-28 23:06 ` Jason Gunthorpe
2020-03-30 13:14 ` Danil Kipnis
2020-03-20 12:16 ` [PATCH v11 24/26] block/rnbd: include client and server modules into kernel compilation Jack Wang
2020-03-28 19:34 ` Bart Van Assche
2020-03-31 7:23 ` Jinpu Wang
2020-03-20 12:16 ` [PATCH v11 25/26] block/rnbd: a bit of documentation Jack Wang
2020-03-28 19:40 ` Bart Van Assche
2020-03-30 10:17 ` Danil Kipnis
2020-03-20 12:16 ` [PATCH v11 26/26] MAINTAINERS: Add maintainers for RNBD/RTRS modules Jack Wang
2020-03-28 19:40 ` Bart Van Assche
2020-03-30 10:12 ` Danil Kipnis
2020-03-26 17:38 ` [PATCH v11 00/26] RTRS (former IBTRS) RDMA Transport Library and RNBD (former IBNBD) RDMA Network Block Device Jinpu Wang
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=8ecc1c47-bad0-dadb-7861-8776b89f0174@acm.org \
--to=bvanassche@acm.org \
--cc=axboe@kernel.dk \
--cc=danil.kipnis@cloud.ionos.com \
--cc=dledford@redhat.com \
--cc=hch@infradead.org \
--cc=jgg@ziepe.ca \
--cc=jinpu.wang@cloud.ionos.com \
--cc=leon@kernel.org \
--cc=linux-block@vger.kernel.org \
--cc=linux-rdma@vger.kernel.org \
--cc=pankaj.gupta@cloud.ionos.com \
--cc=rpenyaev@suse.de \
--cc=sagi@grimberg.me \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).