From 02cdb02ceab1f3dd9ac2bc899fc51f0e0e744782 Mon Sep 17 00:00:00 2001 From: Alex Elder Date: Fri, 10 Aug 2012 13:12:10 -0700 Subject: [PATCH] rbd: kill create_snap sysfs entry Josh proposed the following change, and I don't think I could explain it any better than he did: From: Josh Durgin Date: Tue, 24 Jul 2012 14:22:11 -0700 To: ceph-devel Message-ID: <500F1203.9050605@inktank.com> Right now the kernel still has one piece of rbd management duplicated from the rbd command line tool: snapshot creation. There's nothing special about snapshot creation that makes it advantageous to do from the kernel, so I'd like to remove the create_snap sysfs interface. That is, /sys/bus/rbd/devices//create_snap would be removed. Does anyone rely on the sysfs interface for creating rbd snapshots? If so, how hard would it be to replace with: rbd snap create pool/image@snap Is there any benefit to the sysfs interface that I'm missing? Josh This patch implements this proposal, removing the code that implements the "snap_create" sysfs interface for rbd images. As a result, quite a lot of other supporting code goes away. Suggested-by: Josh Durgin Signed-off-by: Alex Elder Reviewed-by: Josh Durgin --- Documentation/ABI/testing/sysfs-bus-rbd | 6 -- drivers/block/rbd.c | 158 -------------------------------- 2 files changed, 164 deletions(-) diff --git a/Documentation/ABI/testing/sysfs-bus-rbd b/Documentation/ABI/testing/sysfs-bus-rbd index 7cbbe34..6fe4224 100644 --- a/Documentation/ABI/testing/sysfs-bus-rbd +++ b/Documentation/ABI/testing/sysfs-bus-rbd @@ -62,12 +62,6 @@ current_snap The current snapshot for which the device is mapped. -create_snap - - Create a snapshot: - - $ echo > /sys/bus/rbd/devices//snap_create - snap_* A directory per each snapshot diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 34f46c3..e453f8c 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -212,10 +212,6 @@ static int rbd_dev_snaps_update(struct rbd_device *rbd_dev); static int rbd_dev_snaps_register(struct rbd_device *rbd_dev); static void rbd_dev_release(struct device *dev); -static ssize_t rbd_snap_add(struct device *dev, - struct device_attribute *attr, - const char *buf, - size_t count); static void __rbd_remove_snap_dev(struct rbd_snap *snap); static ssize_t rbd_add(struct bus_type *bus, const char *buf, @@ -1375,71 +1371,6 @@ static int rbd_req_sync_unwatch(struct rbd_device *rbd_dev) return ret; } -struct rbd_notify_info { - struct rbd_device *rbd_dev; -}; - -static void rbd_notify_cb(u64 ver, u64 notify_id, u8 opcode, void *data) -{ - struct rbd_device *rbd_dev = (struct rbd_device *)data; - if (!rbd_dev) - return; - - dout("rbd_notify_cb %s notify_id=%llu opcode=%u\n", - rbd_dev->header_name, (unsigned long long) notify_id, - (unsigned int) opcode); -} - -/* - * Request sync osd notify - */ -static int rbd_req_sync_notify(struct rbd_device *rbd_dev) -{ - struct ceph_osd_req_op *ops; - struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; - struct ceph_osd_event *event; - struct rbd_notify_info info; - int payload_len = sizeof(u32) + sizeof(u32); - int ret; - - ops = rbd_create_rw_ops(1, CEPH_OSD_OP_NOTIFY, payload_len); - if (!ops) - return -ENOMEM; - - info.rbd_dev = rbd_dev; - - ret = ceph_osdc_create_event(osdc, rbd_notify_cb, 1, - (void *)&info, &event); - if (ret < 0) - goto fail; - - ops[0].watch.ver = 1; - ops[0].watch.flag = 1; - ops[0].watch.cookie = event->cookie; - ops[0].watch.prot_ver = RADOS_NOTIFY_VER; - ops[0].watch.timeout = 12; - - ret = rbd_req_sync_op(rbd_dev, NULL, - CEPH_NOSNAP, - CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK, - ops, - rbd_dev->header_name, - 0, 0, NULL, NULL, NULL); - if (ret < 0) - goto fail_event; - - ret = ceph_osdc_wait_event(event, CEPH_OSD_TIMEOUT_DEFAULT); - dout("ceph_osdc_wait_event returned %d\n", ret); - rbd_destroy_ops(ops); - return 0; - -fail_event: - ceph_osdc_cancel_event(event); -fail: - rbd_destroy_ops(ops); - return ret; -} - /* * Synchronous osd object method call */ @@ -1761,52 +1692,6 @@ static int rbd_read_header(struct rbd_device *rbd_dev, return ret; } -/* - * create a snapshot - */ -static int rbd_header_add_snap(struct rbd_device *rbd_dev, - const char *snap_name, - gfp_t gfp_flags) -{ - int name_len = strlen(snap_name); - u64 new_snapid; - int ret; - void *data, *p, *e; - struct ceph_mon_client *monc; - - /* we should create a snapshot only if we're pointing at the head */ - if (rbd_dev->mapping.snap_id != CEPH_NOSNAP) - return -EINVAL; - - monc = &rbd_dev->rbd_client->client->monc; - ret = ceph_monc_create_snapid(monc, rbd_dev->pool_id, &new_snapid); - dout("created snapid=%llu\n", (unsigned long long) new_snapid); - if (ret < 0) - return ret; - - data = kmalloc(name_len + 16, gfp_flags); - if (!data) - return -ENOMEM; - - p = data; - e = data + name_len + 16; - - ceph_encode_string_safe(&p, e, snap_name, name_len, bad); - ceph_encode_64_safe(&p, e, new_snapid, bad); - - ret = rbd_req_sync_exec(rbd_dev, rbd_dev->header_name, - "rbd", "snap_add", - data, (size_t) (p - data), NULL, 0, - CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK, - NULL); - - kfree(data); - - return ret < 0 ? ret : 0; -bad: - return -ERANGE; -} - static void __rbd_remove_all_snaps(struct rbd_device *rbd_dev) { struct rbd_snap *snap; @@ -2030,7 +1915,6 @@ static DEVICE_ATTR(name, S_IRUGO, rbd_name_show, NULL); static DEVICE_ATTR(image_id, S_IRUGO, rbd_image_id_show, NULL); static DEVICE_ATTR(refresh, S_IWUSR, NULL, rbd_image_refresh); static DEVICE_ATTR(current_snap, S_IRUGO, rbd_snap_show, NULL); -static DEVICE_ATTR(create_snap, S_IWUSR, NULL, rbd_snap_add); static struct attribute *rbd_attrs[] = { &dev_attr_size.attr, @@ -2042,7 +1926,6 @@ static struct attribute *rbd_attrs[] = { &dev_attr_image_id.attr, &dev_attr_current_snap.attr, &dev_attr_refresh.attr, - &dev_attr_create_snap.attr, NULL }; @@ -2891,47 +2774,6 @@ done: return ret; } -static ssize_t rbd_snap_add(struct device *dev, - struct device_attribute *attr, - const char *buf, - size_t count) -{ - struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); - int ret; - char *name = kmalloc(count + 1, GFP_KERNEL); - if (!name) - return -ENOMEM; - - snprintf(name, count, "%s", buf); - - mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING); - - ret = rbd_header_add_snap(rbd_dev, - name, GFP_KERNEL); - if (ret < 0) - goto err_unlock; - - ret = __rbd_refresh_header(rbd_dev, NULL); - if (ret < 0) - goto err_unlock; - - /* shouldn't hold ctl_mutex when notifying.. notify might - trigger a watch callback that would need to get that mutex */ - mutex_unlock(&ctl_mutex); - - /* make a best effort, don't error if failed */ - rbd_req_sync_notify(rbd_dev); - - ret = count; - kfree(name); - return ret; - -err_unlock: - mutex_unlock(&ctl_mutex); - kfree(name); - return ret; -} - /* * create control files in sysfs * /sys/bus/rbd/... -- 2.7.4