diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-rbd | 4 | ||||
| -rw-r--r-- | drivers/block/rbd.c | 56 |
2 files changed, 25 insertions, 35 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-rbd b/Documentation/ABI/testing/sysfs-bus-rbd index 501adc2a9ec7..2ddd680929d8 100644 --- a/Documentation/ABI/testing/sysfs-bus-rbd +++ b/Documentation/ABI/testing/sysfs-bus-rbd @@ -94,5 +94,5 @@ current_snap parent - Information identifying the pool, image, and snapshot id for - the parent image in a layered rbd image (format 2 only). + Information identifying the chain of parent images in a layered rbd + image. Entries are separated by empty lines. diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 703b728e05fa..7847fbb949ff 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -3685,46 +3685,36 @@ static ssize_t rbd_snap_show(struct device *dev, } /* - * For an rbd v2 image, shows the pool id, image id, and snapshot id - * for the parent image. If there is no parent, simply shows - * "(no parent image)". + * For a v2 image, shows the chain of parent images, separated by empty + * lines. For v1 images or if there is no parent, shows "(no parent + * image)". */ static ssize_t rbd_parent_show(struct device *dev, - struct device_attribute *attr, - char *buf) + struct device_attribute *attr, + char *buf) { struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); - struct rbd_spec *spec = rbd_dev->parent_spec; - int count; - char *bufp = buf; + ssize_t count = 0; - if (!spec) + if (!rbd_dev->parent) return sprintf(buf, "(no parent image)\n"); - count = sprintf(bufp, "pool_id %llu\npool_name %s\n", - (unsigned long long) spec->pool_id, spec->pool_name); - if (count < 0) - return count; - bufp += count; - - count = sprintf(bufp, "image_id %s\nimage_name %s\n", spec->image_id, - spec->image_name ? spec->image_name : "(unknown)"); - if (count < 0) - return count; - bufp += count; - - count = sprintf(bufp, "snap_id %llu\nsnap_name %s\n", - (unsigned long long) spec->snap_id, spec->snap_name); - if (count < 0) - return count; - bufp += count; - - count = sprintf(bufp, "overlap %llu\n", rbd_dev->parent_overlap); - if (count < 0) - return count; - bufp += count; - - return (ssize_t) (bufp - buf); + for ( ; rbd_dev->parent; rbd_dev = rbd_dev->parent) { + struct rbd_spec *spec = rbd_dev->parent_spec; + + count += sprintf(&buf[count], "%s" + "pool_id %llu\npool_name %s\n" + "image_id %s\nimage_name %s\n" + "snap_id %llu\nsnap_name %s\n" + "overlap %llu\n", + !count ? "" : "\n", /* first? */ + spec->pool_id, spec->pool_name, + spec->image_id, spec->image_name ?: "(unknown)", + spec->snap_id, spec->snap_name, + rbd_dev->parent_overlap); + } + + return count; } static ssize_t rbd_image_refresh(struct device *dev, |