]> Pileus Git - ~andy/linux/blobdiff - drivers/block/rbd.c
rbd: don't revalidate so much
[~andy/linux] / drivers / block / rbd.c
index ebf4d470e13fd58c788fe5a39e0872a451ebb815..ab2c788a22adc7ca300bd50aed54798292d7d739 100644 (file)
@@ -358,7 +358,7 @@ static int rbd_img_request_submit(struct rbd_img_request *img_request);
 
 static int rbd_dev_snaps_update(struct rbd_device *rbd_dev);
 
-static void rbd_dev_release(struct device *dev);
+static void rbd_dev_device_release(struct device *dev);
 static void rbd_snap_destroy(struct rbd_snap *snap);
 
 static ssize_t rbd_add(struct bus_type *bus, const char *buf,
@@ -672,35 +672,6 @@ static void rbd_client_release(struct kref *kref)
        kfree(rbdc);
 }
 
-/* Caller has to fill in snapc->seq and snapc->snaps[0..snap_count-1] */
-
-static struct ceph_snap_context *rbd_snap_context_create(u32 snap_count)
-{
-       struct ceph_snap_context *snapc;
-       size_t size;
-
-       size = sizeof (struct ceph_snap_context);
-       size += snap_count * sizeof (snapc->snaps[0]);
-       snapc = kzalloc(size, GFP_KERNEL);
-       if (!snapc)
-               return NULL;
-
-       atomic_set(&snapc->nref, 1);
-       snapc->num_snaps = snap_count;
-
-       return snapc;
-}
-
-static inline void rbd_snap_context_get(struct ceph_snap_context *snapc)
-{
-       (void)ceph_get_snap_context(snapc);
-}
-
-static inline void rbd_snap_context_put(struct ceph_snap_context *snapc)
-{
-       ceph_put_snap_context(snapc);
-}
-
 /*
  * Drop reference to ceph client node. If it's not referenced anymore, release
  * it.
@@ -820,7 +791,7 @@ static int rbd_header_from_disk(struct rbd_image_header *header,
 
        header->image_size = le64_to_cpu(ondisk->image_size);
 
-       header->snapc = rbd_snap_context_create(snap_count);
+       header->snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
        if (!header->snapc)
                goto out_err;
        header->snapc->seq = le64_to_cpu(ondisk->snap_seq);
@@ -893,16 +864,11 @@ static void rbd_dev_mapping_clear(struct rbd_device *rbd_dev)
        rbd_dev->mapping.read_only = true;
 }
 
-static void rbd_header_free(struct rbd_image_header *header)
+static void rbd_dev_clear_mapping(struct rbd_device *rbd_dev)
 {
-       kfree(header->object_prefix);
-       header->object_prefix = NULL;
-       kfree(header->snap_sizes);
-       header->snap_sizes = NULL;
-       kfree(header->snap_names);
-       header->snap_names = NULL;
-       rbd_snap_context_put(header->snapc);
-       header->snapc = NULL;
+       rbd_dev->mapping.size = 0;
+       rbd_dev->mapping.features = 0;
+       rbd_dev->mapping.read_only = true;
 }
 
 static const char *rbd_segment_name(struct rbd_device *rbd_dev, u64 offset)
@@ -1758,7 +1724,7 @@ static struct rbd_img_request *rbd_img_request_create(
 
        if (write_request) {
                down_read(&rbd_dev->header_rwsem);
-               rbd_snap_context_get(rbd_dev->header.snapc);
+               ceph_get_snap_context(rbd_dev->header.snapc);
                up_read(&rbd_dev->header_rwsem);
        }
 
@@ -1810,7 +1776,7 @@ static void rbd_img_request_destroy(struct kref *kref)
        rbd_assert(img_request->obj_request_count == 0);
 
        if (img_request_write_test(img_request))
-               rbd_snap_context_put(img_request->snapc);
+               ceph_put_snap_context(img_request->snapc);
 
        if (img_request_child_test(img_request))
                rbd_obj_request_put(img_request->obj_request);
@@ -3076,7 +3042,7 @@ static int rbd_dev_v1_refresh(struct rbd_device *rbd_dev, u64 *hver)
        kfree(rbd_dev->header.snap_sizes);
        kfree(rbd_dev->header.snap_names);
        /* osd requests may still refer to snapc */
-       rbd_snap_context_put(rbd_dev->header.snapc);
+       ceph_put_snap_context(rbd_dev->header.snapc);
 
        if (hver)
                *hver = h.obj_version;
@@ -3099,19 +3065,22 @@ static int rbd_dev_v1_refresh(struct rbd_device *rbd_dev, u64 *hver)
 
 static int rbd_dev_refresh(struct rbd_device *rbd_dev, u64 *hver)
 {
+       u64 image_size;
        int ret;
 
        rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
+       image_size = rbd_dev->header.image_size;
        mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
        if (rbd_dev->image_format == 1)
                ret = rbd_dev_v1_refresh(rbd_dev, hver);
        else
                ret = rbd_dev_v2_refresh(rbd_dev, hver);
        mutex_unlock(&ctl_mutex);
-       revalidate_disk(rbd_dev->disk);
        if (ret)
                rbd_warn(rbd_dev, "got notification but failed to "
                           " update snaps: %d\n", ret);
+       if (image_size != rbd_dev->header.image_size)
+               revalidate_disk(rbd_dev->disk);
 
        return ret;
 }
@@ -3919,7 +3888,7 @@ static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev, u64 *ver)
                goto out;
        ret = 0;
 
-       snapc = rbd_snap_context_create(snap_count);
+       snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
        if (!snapc) {
                ret = -ENOMEM;
                goto out;
@@ -4024,20 +3993,12 @@ static char *rbd_dev_snap_info(struct rbd_device *rbd_dev, u32 which,
 static int rbd_dev_v2_refresh(struct rbd_device *rbd_dev, u64 *hver)
 {
        int ret;
-       __u8 obj_order;
 
        down_write(&rbd_dev->header_rwsem);
 
-       /* Grab old order first, to see if it changes */
-
-       obj_order = rbd_dev->header.obj_order,
        ret = rbd_dev_v2_image_size(rbd_dev);
        if (ret)
                goto out;
-       if (rbd_dev->header.obj_order != obj_order) {
-               ret = -EIO;
-               goto out;
-       }
        rbd_update_mapping_size(rbd_dev);
 
        ret = rbd_dev_v2_snap_context(rbd_dev, hver);
@@ -4190,7 +4151,7 @@ static int rbd_bus_add_dev(struct rbd_device *rbd_dev)
        dev->bus = &rbd_bus_type;
        dev->type = &rbd_device_type;
        dev->parent = &rbd_root_dev;
-       dev->release = rbd_dev_release;
+       dev->release = rbd_dev_device_release;
        dev_set_name(dev, "%d", rbd_dev->dev_id);
        ret = device_register(dev);
 
@@ -4589,21 +4550,30 @@ out:
        return ret;
 }
 
-static int rbd_dev_v1_probe(struct rbd_device *rbd_dev)
+/* Undo whatever state changes are made by v1 or v2 image probe */
+
+static void rbd_dev_unprobe(struct rbd_device *rbd_dev)
 {
-       int ret;
-       size_t size;
+       struct rbd_image_header *header;
 
-       /* Record the header object name for this rbd image. */
+       rbd_dev_remove_parent(rbd_dev);
+       rbd_spec_put(rbd_dev->parent_spec);
+       rbd_dev->parent_spec = NULL;
+       rbd_dev->parent_overlap = 0;
 
-       size = strlen(rbd_dev->spec->image_name) + sizeof (RBD_SUFFIX);
-       rbd_dev->header_name = kmalloc(size, GFP_KERNEL);
-       if (!rbd_dev->header_name) {
-               ret = -ENOMEM;
-               goto out_err;
-       }
-       sprintf(rbd_dev->header_name, "%s%s",
-               rbd_dev->spec->image_name, RBD_SUFFIX);
+       /* Free dynamic fields from the header, then zero it out */
+
+       header = &rbd_dev->header;
+       ceph_put_snap_context(header->snapc);
+       kfree(header->snap_sizes);
+       kfree(header->snap_names);
+       kfree(header->object_prefix);
+       memset(header, 0, sizeof (*header));
+}
+
+static int rbd_dev_v1_probe(struct rbd_device *rbd_dev)
+{
+       int ret;
 
        /* Populate rbd image metadata */
 
@@ -4632,22 +4602,9 @@ out_err:
 
 static int rbd_dev_v2_probe(struct rbd_device *rbd_dev)
 {
-       size_t size;
        int ret;
        u64 ver = 0;
 
-       /*
-        * Image id was filled in by the caller.  Record the header
-        * object name for this rbd image.
-        */
-       size = sizeof (RBD_HEADER_PREFIX) + strlen(rbd_dev->spec->image_id);
-       rbd_dev->header_name = kmalloc(size, GFP_KERNEL);
-       if (!rbd_dev->header_name)
-               return -ENOMEM;
-       sprintf(rbd_dev->header_name, "%s%s",
-                       RBD_HEADER_PREFIX, rbd_dev->spec->image_id);
-
-       /* Get the size and object order for the image */
        ret = rbd_dev_v2_image_size(rbd_dev);
        if (ret)
                goto out_err;
@@ -4670,8 +4627,15 @@ static int rbd_dev_v2_probe(struct rbd_device *rbd_dev)
                ret = rbd_dev_v2_parent_info(rbd_dev);
                if (ret)
                        goto out_err;
-               rbd_warn(rbd_dev, "WARNING: kernel support for "
-                                       "layered rbd images is EXPERIMENTAL!");
+
+               /*
+                * Don't print a warning for parent images.  We can
+                * tell this point because we won't know its pool
+                * name yet (just its pool id).
+                */
+               if (rbd_dev->spec->pool_name)
+                       rbd_warn(rbd_dev, "WARNING: kernel layering "
+                                       "is EXPERIMENTAL!");
        }
 
        /* If the image supports fancy striping, get its parameters */
@@ -4751,14 +4715,10 @@ out_err:
        return ret;
 }
 
-static int rbd_dev_probe_finish(struct rbd_device *rbd_dev)
+static int rbd_dev_device_setup(struct rbd_device *rbd_dev)
 {
        int ret;
 
-       ret = rbd_dev_header_watch_sync(rbd_dev, 1);
-       if (ret)
-               return ret;
-
        ret = rbd_dev_mapping_set(rbd_dev);
        if (ret)
                return ret;
@@ -4810,6 +4770,51 @@ err_out_id:
        return ret;
 }
 
+static int rbd_dev_header_name(struct rbd_device *rbd_dev)
+{
+       struct rbd_spec *spec = rbd_dev->spec;
+       size_t size;
+
+       /* Record the header object name for this rbd image. */
+
+       rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
+
+       if (rbd_dev->image_format == 1)
+               size = strlen(spec->image_name) + sizeof (RBD_SUFFIX);
+       else
+               size = sizeof (RBD_HEADER_PREFIX) + strlen(spec->image_id);
+
+       rbd_dev->header_name = kmalloc(size, GFP_KERNEL);
+       if (!rbd_dev->header_name)
+               return -ENOMEM;
+
+       if (rbd_dev->image_format == 1)
+               sprintf(rbd_dev->header_name, "%s%s",
+                       spec->image_name, RBD_SUFFIX);
+       else
+               sprintf(rbd_dev->header_name, "%s%s",
+                       RBD_HEADER_PREFIX, spec->image_id);
+       return 0;
+}
+
+static void rbd_dev_image_release(struct rbd_device *rbd_dev)
+{
+       int ret;
+
+       rbd_remove_all_snaps(rbd_dev);
+       rbd_dev_unprobe(rbd_dev);
+       ret = rbd_dev_header_watch_sync(rbd_dev, 0);
+       if (ret)
+               rbd_warn(rbd_dev, "failed to cancel watch event (%d)\n", ret);
+       kfree(rbd_dev->header_name);
+       rbd_dev->header_name = NULL;
+       rbd_dev->image_format = 0;
+       kfree(rbd_dev->spec->image_id);
+       rbd_dev->spec->image_id = NULL;
+
+       rbd_dev_destroy(rbd_dev);
+}
+
 /*
  * Probe for the existence of the header object for the given rbd
  * device.  For format 2 images this includes determining the image
@@ -4818,6 +4823,7 @@ err_out_id:
 static int rbd_dev_image_probe(struct rbd_device *rbd_dev)
 {
        int ret;
+       int tmp;
 
        /*
         * Get the id from the image id object.  If it's not a
@@ -4830,36 +4836,46 @@ static int rbd_dev_image_probe(struct rbd_device *rbd_dev)
        rbd_assert(rbd_dev->spec->image_id);
        rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
 
+       ret = rbd_dev_header_name(rbd_dev);
+       if (ret)
+               goto err_out_format;
+
+       ret = rbd_dev_header_watch_sync(rbd_dev, 1);
+       if (ret)
+               goto out_header_name;
+
        if (rbd_dev->image_format == 1)
                ret = rbd_dev_v1_probe(rbd_dev);
        else
                ret = rbd_dev_v2_probe(rbd_dev);
        if (ret)
-               goto out_err;
+               goto err_out_watch;
 
        ret = rbd_dev_snaps_update(rbd_dev);
        if (ret)
-               goto out_err;
+               goto err_out_probe;
 
        ret = rbd_dev_spec_update(rbd_dev);
        if (ret)
                goto err_out_snaps;
 
        ret = rbd_dev_probe_parent(rbd_dev);
-       if (ret)
-               goto err_out_snaps;
-
-       ret = rbd_dev_probe_finish(rbd_dev);
-       if (ret)
-               goto err_out_parent;
+       if (!ret)
+               return 0;
 
-       return ret;
-err_out_parent:
-       rbd_dev_remove_parent(rbd_dev);
-       rbd_header_free(&rbd_dev->header);
 err_out_snaps:
        rbd_remove_all_snaps(rbd_dev);
-out_err:
+err_out_probe:
+       rbd_dev_unprobe(rbd_dev);
+err_out_watch:
+       tmp = rbd_dev_header_watch_sync(rbd_dev, 0);
+       if (tmp)
+               rbd_warn(rbd_dev, "unable to tear down watch request\n");
+out_header_name:
+       kfree(rbd_dev->header_name);
+       rbd_dev->header_name = NULL;
+err_out_format:
+       rbd_dev->image_format = 0;
        kfree(rbd_dev->spec->image_id);
        rbd_dev->spec->image_id = NULL;
 
@@ -4925,9 +4941,12 @@ static ssize_t rbd_add(struct bus_type *bus,
        if (rc < 0)
                goto err_out_rbd_dev;
 
-       return count;
+       rc = rbd_dev_device_setup(rbd_dev);
+       if (!rc)
+               return count;
+
+       rbd_dev_image_release(rbd_dev);
 err_out_rbd_dev:
-       kfree(rbd_dev->header_name);
        rbd_dev_destroy(rbd_dev);
 err_out_client:
        rbd_put_client(rbdc);
@@ -4961,30 +4980,17 @@ static struct rbd_device *__rbd_get_dev(unsigned long dev_id)
        return NULL;
 }
 
-static void rbd_dev_release(struct device *dev)
+static void rbd_dev_device_release(struct device *dev)
 {
        struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
 
-       if (rbd_dev->watch_event)
-               rbd_dev_header_watch_sync(rbd_dev, 0);
-
-       /* clean up and free blkdev */
        rbd_free_disk(rbd_dev);
+       clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
+       rbd_dev_clear_mapping(rbd_dev);
        unregister_blkdev(rbd_dev->major, rbd_dev->name);
-
-       /* release allocated disk header fields */
-       rbd_header_free(&rbd_dev->header);
-
-       /* done with the id, and with the rbd_dev */
+       rbd_dev->major = 0;
        rbd_dev_id_put(rbd_dev);
        rbd_dev_mapping_clear(rbd_dev);
-       rbd_assert(rbd_dev->rbd_client != NULL);
-       rbd_spec_put(rbd_dev->parent_spec);
-       kfree(rbd_dev->header_name);
-       rbd_dev_destroy(rbd_dev);
-
-       /* release module ref */
-       module_put(THIS_MODULE);
 }
 
 static void rbd_dev_remove_parent(struct rbd_device *rbd_dev)
@@ -5003,8 +5009,7 @@ static void rbd_dev_remove_parent(struct rbd_device *rbd_dev)
                        second = third;
                }
                rbd_assert(second);
-               rbd_remove_all_snaps(second);
-               rbd_bus_del_dev(second);
+               rbd_dev_image_release(second);
                first->parent = NULL;
                first->parent_overlap = 0;
 
@@ -5019,13 +5024,13 @@ static ssize_t rbd_remove(struct bus_type *bus,
                          size_t count)
 {
        struct rbd_device *rbd_dev = NULL;
-       int target_id, rc;
+       int target_id;
        unsigned long ul;
-       int ret = count;
+       int ret;
 
-       rc = strict_strtoul(buf, 10, &ul);
-       if (rc)
-               return rc;
+       ret = strict_strtoul(buf, 10, &ul);
+       if (ret)
+               return ret;
 
        /* convert to int; abort if we lost anything in the conversion */
        target_id = (int) ul;
@@ -5048,11 +5053,10 @@ static ssize_t rbd_remove(struct bus_type *bus,
        spin_unlock_irq(&rbd_dev->lock);
        if (ret < 0)
                goto done;
-
-       rbd_dev_remove_parent(rbd_dev);
-
-       rbd_remove_all_snaps(rbd_dev);
+       ret = count;
        rbd_bus_del_dev(rbd_dev);
+       rbd_dev_image_release(rbd_dev);
+       module_put(THIS_MODULE);
 done:
        mutex_unlock(&ctl_mutex);