@@ -4584,47 +4584,95 @@ static int rbd_dev_v2_features(struct rbd_device *rbd_dev)
&rbd_dev->header.features);
}
+struct parent_image_info {
+ u64 pool_id;
+ const char *image_id;
+ u64 snap_id;
+
+ u64 overlap;
+};
+
+/*
+ * The caller is responsible for @pii.
+ */
+static int __get_parent_info_legacy(struct rbd_device *rbd_dev,
+ struct page *req_page,
+ struct page *reply_page,
+ struct parent_image_info *pii)
+{
+ struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
+ size_t reply_len = PAGE_SIZE;
+ void *p, *end;
+ int ret;
+
+ ret = ceph_osdc_call(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc,
+ "rbd", "get_parent", CEPH_OSD_FLAG_READ,
+ req_page, sizeof(u64), reply_page, &reply_len);
+ if (ret)
+ return ret;
+
+ p = page_address(reply_page);
+ end = p + reply_len;
+ ceph_decode_64_safe(&p, end, pii->pool_id, e_inval);
+ pii->image_id = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
+ if (IS_ERR(pii->image_id)) {
+ ret = PTR_ERR(pii->image_id);
+ pii->image_id = NULL;
+ return ret;
+ }
+ ceph_decode_64_safe(&p, end, pii->snap_id, e_inval);
+ ceph_decode_64_safe(&p, end, pii->overlap, e_inval);
+
+ return 0;
+
+e_inval:
+ return -EINVAL;
+}
+
+static int get_parent_info(struct rbd_device *rbd_dev,
+ struct parent_image_info *pii)
+{
+ struct page *req_page, *reply_page;
+ void *p;
+ int ret;
+
+ req_page = alloc_page(GFP_KERNEL);
+ if (!req_page)
+ return -ENOMEM;
+
+ reply_page = alloc_page(GFP_KERNEL);
+ if (!reply_page) {
+ __free_page(req_page);
+ return -ENOMEM;
+ }
+
+ p = page_address(req_page);
+ ceph_encode_64(&p, rbd_dev->spec->snap_id);
+ ret = __get_parent_info_legacy(rbd_dev, req_page, reply_page, pii);
+
+ __free_page(req_page);
+ __free_page(reply_page);
+ return ret;
+}
+
static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev)
{
struct rbd_spec *parent_spec;
- size_t size;
- void *reply_buf = NULL;
- __le64 snapid;
- void *p;
- void *end;
- u64 pool_id;
- char *image_id;
- u64 snap_id;
- u64 overlap;
+ struct parent_image_info pii = { 0 };
int ret;
parent_spec = rbd_spec_alloc();
if (!parent_spec)
return -ENOMEM;
- size = sizeof (__le64) + /* pool_id */
- sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX + /* image_id */
- sizeof (__le64) + /* snap_id */
- sizeof (__le64); /* overlap */
- reply_buf = kmalloc(size, GFP_KERNEL);
- if (!reply_buf) {
- ret = -ENOMEM;
+ ret = get_parent_info(rbd_dev, &pii);
+ if (ret)
goto out_err;
- }
- snapid = cpu_to_le64(rbd_dev->spec->snap_id);
- ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
- &rbd_dev->header_oloc, "get_parent",
- &snapid, sizeof(snapid), reply_buf, size);
- dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
- if (ret < 0)
- goto out_err;
+ dout("%s pool_id %llu image_id %s snap_id %llu overlap %llu\n",
+ __func__, pii.pool_id, pii.image_id, pii.snap_id, pii.overlap);
- p = reply_buf;
- end = reply_buf + ret;
- ret = -ERANGE;
- ceph_decode_64_safe(&p, end, pool_id, out_err);
- if (pool_id == CEPH_NOPOOL) {
+ if (pii.pool_id == CEPH_NOPOOL) {
/*
* Either the parent never existed, or we have
* record of it but the image got flattened so it no
@@ -4647,19 +4695,11 @@ static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev)
/* The ceph file layout needs to fit pool id in 32 bits */
ret = -EIO;
- if (pool_id > (u64)U32_MAX) {
+ if (pii.pool_id > (u64)U32_MAX) {
rbd_warn(NULL, "parent pool id too large (%llu > %u)",
- (unsigned long long)pool_id, U32_MAX);
- goto out_err;
- }
-
- image_id = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
- if (IS_ERR(image_id)) {
- ret = PTR_ERR(image_id);
+ (unsigned long long)pii.pool_id, U32_MAX);
goto out_err;
}
- ceph_decode_64_safe(&p, end, snap_id, out_err);
- ceph_decode_64_safe(&p, end, overlap, out_err);
/*
* The parent won't change (except when the clone is
@@ -4667,9 +4707,10 @@ static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev)
* record the parent spec we have not already done so.
*/
if (!rbd_dev->parent_spec) {
- parent_spec->pool_id = pool_id;
- parent_spec->image_id = image_id;
- parent_spec->snap_id = snap_id;
+ parent_spec->pool_id = pii.pool_id;
+ parent_spec->image_id = pii.image_id;
+ pii.image_id = NULL;
+ parent_spec->snap_id = pii.snap_id;
/* TODO: support cloning across namespaces */
if (rbd_dev->spec->pool_ns) {
@@ -4683,15 +4724,13 @@ static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev)
rbd_dev->parent_spec = parent_spec;
parent_spec = NULL; /* rbd_dev now owns this */
- } else {
- kfree(image_id);
}
/*
* We always update the parent overlap. If it's zero we issue
* a warning, as we will proceed as if there was no parent.
*/
- if (!overlap) {
+ if (!pii.overlap) {
if (parent_spec) {
/* refresh, careful to warn just once */
if (rbd_dev->parent_overlap)
@@ -4702,14 +4741,13 @@ static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev)
rbd_warn(rbd_dev, "clone is standalone (overlap 0)");
}
}
- rbd_dev->parent_overlap = overlap;
+ rbd_dev->parent_overlap = pii.overlap;
out:
ret = 0;
out_err:
- kfree(reply_buf);
+ kfree(pii.image_id);
rbd_spec_put(parent_spec);
-
return ret;
}
In preparation for the new parent_get and parent_overlap_get class methods, factor out the fetching and decoding of parent data. As a side effect, we now decode all four fields in the "no parent" case. Signed-off-by: Ilya Dryomov <idryomov@gmail.com> --- drivers/block/rbd.c | 134 +++++++++++++++++++++++++++++++++------------------- 1 file changed, 86 insertions(+), 48 deletions(-)