* [PATCH for 5.4 2/4] rbd: decouple header read-in from updating rbd_dev->header
2023-10-05 15:29 [PATCH for 5.4 0/4] rbd: fix a deadlock around header_rwsem and lock_rwsem Ilya Dryomov
2023-10-05 15:29 ` [PATCH for 5.4 1/4] rbd: move rbd_dev_refresh() definition Ilya Dryomov
@ 2023-10-05 15:29 ` Ilya Dryomov
2023-10-05 15:29 ` [PATCH for 5.4 3/4] rbd: decouple parent info read-in from updating rbd_dev Ilya Dryomov
2023-10-05 15:29 ` [PATCH for 5.4 4/4] rbd: take header_rwsem in rbd_dev_refresh() only when updating Ilya Dryomov
3 siblings, 0 replies; 5+ messages in thread
From: Ilya Dryomov @ 2023-10-05 15:29 UTC (permalink / raw)
To: stable; +Cc: Greg KH, Dongsheng Yang
commit 510a7330c82a7754d5df0117a8589e8a539067c7 upstream.
Make rbd_dev_header_info() populate a passed struct rbd_image_header
instead of rbd_dev->header and introduce rbd_dev_update_header() for
updating mutable fields in rbd_dev->header upon refresh. The initial
read-in of both mutable and immutable fields in rbd_dev_image_probe()
passes in rbd_dev->header so no update step is required there.
rbd_init_layout() is now called directly from rbd_dev_image_probe()
instead of individually in format 1 and format 2 implementations.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Dongsheng Yang <dongsheng.yang@easystack.cn>
[idryomov@gmail.com: backport to 5.4: _rbd_dev_v2_snap_features()
doesn't have read_only param]
---
drivers/block/rbd.c | 205 ++++++++++++++++++++++++--------------------
1 file changed, 114 insertions(+), 91 deletions(-)
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index e015b8610e27..17d802effdc4 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -626,7 +626,8 @@ void rbd_warn(struct rbd_device *rbd_dev, const char *fmt, ...)
static void rbd_dev_remove_parent(struct rbd_device *rbd_dev);
static int rbd_dev_refresh(struct rbd_device *rbd_dev);
-static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev);
+static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev,
+ struct rbd_image_header *header);
static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
u64 snap_id);
static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
@@ -1096,15 +1097,24 @@ static void rbd_init_layout(struct rbd_device *rbd_dev)
RCU_INIT_POINTER(rbd_dev->layout.pool_ns, NULL);
}
+static void rbd_image_header_cleanup(struct rbd_image_header *header)
+{
+ kfree(header->object_prefix);
+ ceph_put_snap_context(header->snapc);
+ kfree(header->snap_sizes);
+ kfree(header->snap_names);
+
+ memset(header, 0, sizeof(*header));
+}
+
/*
* Fill an rbd image header with information from the given format 1
* on-disk header.
*/
-static int rbd_header_from_disk(struct rbd_device *rbd_dev,
- struct rbd_image_header_ondisk *ondisk)
+static int rbd_header_from_disk(struct rbd_image_header *header,
+ struct rbd_image_header_ondisk *ondisk,
+ bool first_time)
{
- struct rbd_image_header *header = &rbd_dev->header;
- bool first_time = header->object_prefix == NULL;
struct ceph_snap_context *snapc;
char *object_prefix = NULL;
char *snap_names = NULL;
@@ -1171,11 +1181,6 @@ static int rbd_header_from_disk(struct rbd_device *rbd_dev,
if (first_time) {
header->object_prefix = object_prefix;
header->obj_order = ondisk->options.order;
- rbd_init_layout(rbd_dev);
- } else {
- ceph_put_snap_context(header->snapc);
- kfree(header->snap_names);
- kfree(header->snap_sizes);
}
/* The remaining fields always get updated (when we refresh) */
@@ -4981,7 +4986,9 @@ static int rbd_obj_read_sync(struct rbd_device *rbd_dev,
* return, the rbd_dev->header field will contain up-to-date
* information about the image.
*/
-static int rbd_dev_v1_header_info(struct rbd_device *rbd_dev)
+static int rbd_dev_v1_header_info(struct rbd_device *rbd_dev,
+ struct rbd_image_header *header,
+ bool first_time)
{
struct rbd_image_header_ondisk *ondisk = NULL;
u32 snap_count = 0;
@@ -5029,7 +5036,7 @@ static int rbd_dev_v1_header_info(struct rbd_device *rbd_dev)
snap_count = le32_to_cpu(ondisk->snap_count);
} while (snap_count != want_count);
- ret = rbd_header_from_disk(rbd_dev, ondisk);
+ ret = rbd_header_from_disk(header, ondisk, first_time);
out:
kfree(ondisk);
@@ -5642,17 +5649,12 @@ static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
return 0;
}
-static int rbd_dev_v2_image_size(struct rbd_device *rbd_dev)
-{
- return _rbd_dev_v2_snap_size(rbd_dev, CEPH_NOSNAP,
- &rbd_dev->header.obj_order,
- &rbd_dev->header.image_size);
-}
-
-static int rbd_dev_v2_object_prefix(struct rbd_device *rbd_dev)
+static int rbd_dev_v2_object_prefix(struct rbd_device *rbd_dev,
+ char **pobject_prefix)
{
size_t size;
void *reply_buf;
+ char *object_prefix;
int ret;
void *p;
@@ -5670,16 +5672,16 @@ static int rbd_dev_v2_object_prefix(struct rbd_device *rbd_dev)
goto out;
p = reply_buf;
- rbd_dev->header.object_prefix = ceph_extract_encoded_string(&p,
- p + ret, NULL, GFP_NOIO);
+ object_prefix = ceph_extract_encoded_string(&p, p + ret, NULL,
+ GFP_NOIO);
+ if (IS_ERR(object_prefix)) {
+ ret = PTR_ERR(object_prefix);
+ goto out;
+ }
ret = 0;
- if (IS_ERR(rbd_dev->header.object_prefix)) {
- ret = PTR_ERR(rbd_dev->header.object_prefix);
- rbd_dev->header.object_prefix = NULL;
- } else {
- dout(" object_prefix = %s\n", rbd_dev->header.object_prefix);
- }
+ *pobject_prefix = object_prefix;
+ dout(" object_prefix = %s\n", object_prefix);
out:
kfree(reply_buf);
@@ -5724,12 +5726,6 @@ static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
return 0;
}
-static int rbd_dev_v2_features(struct rbd_device *rbd_dev)
-{
- return _rbd_dev_v2_snap_features(rbd_dev, CEPH_NOSNAP,
- &rbd_dev->header.features);
-}
-
/*
* These are generic image flags, but since they are used only for
* object map, store them in rbd_dev->object_map_flags.
@@ -6004,14 +6000,14 @@ static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev)
return ret;
}
-static int rbd_dev_v2_striping_info(struct rbd_device *rbd_dev)
+static int rbd_dev_v2_striping_info(struct rbd_device *rbd_dev,
+ u64 *stripe_unit, u64 *stripe_count)
{
struct {
__le64 stripe_unit;
__le64 stripe_count;
} __attribute__ ((packed)) striping_info_buf = { 0 };
size_t size = sizeof (striping_info_buf);
- void *p;
int ret;
ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
@@ -6023,27 +6019,33 @@ static int rbd_dev_v2_striping_info(struct rbd_device *rbd_dev)
if (ret < size)
return -ERANGE;
- p = &striping_info_buf;
- rbd_dev->header.stripe_unit = ceph_decode_64(&p);
- rbd_dev->header.stripe_count = ceph_decode_64(&p);
+ *stripe_unit = le64_to_cpu(striping_info_buf.stripe_unit);
+ *stripe_count = le64_to_cpu(striping_info_buf.stripe_count);
+ dout(" stripe_unit = %llu stripe_count = %llu\n", *stripe_unit,
+ *stripe_count);
+
return 0;
}
-static int rbd_dev_v2_data_pool(struct rbd_device *rbd_dev)
+static int rbd_dev_v2_data_pool(struct rbd_device *rbd_dev, s64 *data_pool_id)
{
- __le64 data_pool_id;
+ __le64 data_pool_buf;
int ret;
ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
&rbd_dev->header_oloc, "get_data_pool",
- NULL, 0, &data_pool_id, sizeof(data_pool_id));
+ NULL, 0, &data_pool_buf,
+ sizeof(data_pool_buf));
+ dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
if (ret < 0)
return ret;
- if (ret < sizeof(data_pool_id))
+ if (ret < sizeof(data_pool_buf))
return -EBADMSG;
- rbd_dev->header.data_pool_id = le64_to_cpu(data_pool_id);
- WARN_ON(rbd_dev->header.data_pool_id == CEPH_NOPOOL);
+ *data_pool_id = le64_to_cpu(data_pool_buf);
+ dout(" data_pool_id = %lld\n", *data_pool_id);
+ WARN_ON(*data_pool_id == CEPH_NOPOOL);
+
return 0;
}
@@ -6235,7 +6237,8 @@ static int rbd_spec_fill_names(struct rbd_device *rbd_dev)
return ret;
}
-static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev)
+static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev,
+ struct ceph_snap_context **psnapc)
{
size_t size;
int ret;
@@ -6296,9 +6299,7 @@ static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev)
for (i = 0; i < snap_count; i++)
snapc->snaps[i] = ceph_decode_64(&p);
- ceph_put_snap_context(rbd_dev->header.snapc);
- rbd_dev->header.snapc = snapc;
-
+ *psnapc = snapc;
dout(" snap context seq = %llu, snap_count = %u\n",
(unsigned long long)seq, (unsigned int)snap_count);
out:
@@ -6347,38 +6348,42 @@ static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
return snap_name;
}
-static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev)
+static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev,
+ struct rbd_image_header *header,
+ bool first_time)
{
- bool first_time = rbd_dev->header.object_prefix == NULL;
int ret;
- ret = rbd_dev_v2_image_size(rbd_dev);
+ ret = _rbd_dev_v2_snap_size(rbd_dev, CEPH_NOSNAP,
+ first_time ? &header->obj_order : NULL,
+ &header->image_size);
if (ret)
return ret;
if (first_time) {
- ret = rbd_dev_v2_header_onetime(rbd_dev);
+ ret = rbd_dev_v2_header_onetime(rbd_dev, header);
if (ret)
return ret;
}
- ret = rbd_dev_v2_snap_context(rbd_dev);
- if (ret && first_time) {
- kfree(rbd_dev->header.object_prefix);
- rbd_dev->header.object_prefix = NULL;
- }
+ ret = rbd_dev_v2_snap_context(rbd_dev, &header->snapc);
+ if (ret)
+ return ret;
- return ret;
+ return 0;
}
-static int rbd_dev_header_info(struct rbd_device *rbd_dev)
+static int rbd_dev_header_info(struct rbd_device *rbd_dev,
+ struct rbd_image_header *header,
+ bool first_time)
{
rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
+ rbd_assert(!header->object_prefix && !header->snapc);
if (rbd_dev->image_format == 1)
- return rbd_dev_v1_header_info(rbd_dev);
+ return rbd_dev_v1_header_info(rbd_dev, header, first_time);
- return rbd_dev_v2_header_info(rbd_dev);
+ return rbd_dev_v2_header_info(rbd_dev, header, first_time);
}
/*
@@ -6728,60 +6733,49 @@ static int rbd_dev_image_id(struct rbd_device *rbd_dev)
*/
static void rbd_dev_unprobe(struct rbd_device *rbd_dev)
{
- struct rbd_image_header *header;
-
rbd_dev_parent_put(rbd_dev);
rbd_object_map_free(rbd_dev);
rbd_dev_mapping_clear(rbd_dev);
/* 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));
+ rbd_image_header_cleanup(&rbd_dev->header);
}
-static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev)
+static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev,
+ struct rbd_image_header *header)
{
int ret;
- ret = rbd_dev_v2_object_prefix(rbd_dev);
+ ret = rbd_dev_v2_object_prefix(rbd_dev, &header->object_prefix);
if (ret)
- goto out_err;
+ return ret;
/*
* Get the and check features for the image. Currently the
* features are assumed to never change.
*/
- ret = rbd_dev_v2_features(rbd_dev);
+ ret = _rbd_dev_v2_snap_features(rbd_dev, CEPH_NOSNAP,
+ &header->features);
if (ret)
- goto out_err;
+ return ret;
/* If the image supports fancy striping, get its parameters */
- if (rbd_dev->header.features & RBD_FEATURE_STRIPINGV2) {
- ret = rbd_dev_v2_striping_info(rbd_dev);
- if (ret < 0)
- goto out_err;
+ if (header->features & RBD_FEATURE_STRIPINGV2) {
+ ret = rbd_dev_v2_striping_info(rbd_dev, &header->stripe_unit,
+ &header->stripe_count);
+ if (ret)
+ return ret;
}
- if (rbd_dev->header.features & RBD_FEATURE_DATA_POOL) {
- ret = rbd_dev_v2_data_pool(rbd_dev);
+ if (header->features & RBD_FEATURE_DATA_POOL) {
+ ret = rbd_dev_v2_data_pool(rbd_dev, &header->data_pool_id);
if (ret)
- goto out_err;
+ return ret;
}
- rbd_init_layout(rbd_dev);
return 0;
-
-out_err:
- rbd_dev->header.features = 0;
- kfree(rbd_dev->header.object_prefix);
- rbd_dev->header.object_prefix = NULL;
- return ret;
}
/*
@@ -6959,10 +6953,12 @@ static int rbd_dev_image_probe(struct rbd_device *rbd_dev, int depth)
if (!depth)
down_write(&rbd_dev->header_rwsem);
- ret = rbd_dev_header_info(rbd_dev);
+ ret = rbd_dev_header_info(rbd_dev, &rbd_dev->header, true);
if (ret)
goto err_out_probe;
+ rbd_init_layout(rbd_dev);
+
/*
* If this image is the one being mapped, we have pool name and
* id, image name and id, and snap name - need to fill snap id.
@@ -7022,15 +7018,39 @@ static int rbd_dev_image_probe(struct rbd_device *rbd_dev, int depth)
return ret;
}
+static void rbd_dev_update_header(struct rbd_device *rbd_dev,
+ struct rbd_image_header *header)
+{
+ rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
+ rbd_assert(rbd_dev->header.object_prefix); /* !first_time */
+
+ rbd_dev->header.image_size = header->image_size;
+
+ ceph_put_snap_context(rbd_dev->header.snapc);
+ rbd_dev->header.snapc = header->snapc;
+ header->snapc = NULL;
+
+ if (rbd_dev->image_format == 1) {
+ kfree(rbd_dev->header.snap_names);
+ rbd_dev->header.snap_names = header->snap_names;
+ header->snap_names = NULL;
+
+ kfree(rbd_dev->header.snap_sizes);
+ rbd_dev->header.snap_sizes = header->snap_sizes;
+ header->snap_sizes = NULL;
+ }
+}
+
static int rbd_dev_refresh(struct rbd_device *rbd_dev)
{
+ struct rbd_image_header header = { 0 };
u64 mapping_size;
int ret;
down_write(&rbd_dev->header_rwsem);
mapping_size = rbd_dev->mapping.size;
- ret = rbd_dev_header_info(rbd_dev);
+ ret = rbd_dev_header_info(rbd_dev, &header, false);
if (ret)
goto out;
@@ -7044,6 +7064,8 @@ static int rbd_dev_refresh(struct rbd_device *rbd_dev)
goto out;
}
+ rbd_dev_update_header(rbd_dev, &header);
+
if (rbd_dev->spec->snap_id == CEPH_NOSNAP) {
rbd_dev->mapping.size = rbd_dev->header.image_size;
} else {
@@ -7056,6 +7078,7 @@ static int rbd_dev_refresh(struct rbd_device *rbd_dev)
if (!ret && mapping_size != rbd_dev->mapping.size)
rbd_dev_update_size(rbd_dev);
+ rbd_image_header_cleanup(&header);
return ret;
}
--
2.41.0
^ permalink raw reply related [flat|nested] 5+ messages in thread* [PATCH for 5.4 3/4] rbd: decouple parent info read-in from updating rbd_dev
2023-10-05 15:29 [PATCH for 5.4 0/4] rbd: fix a deadlock around header_rwsem and lock_rwsem Ilya Dryomov
2023-10-05 15:29 ` [PATCH for 5.4 1/4] rbd: move rbd_dev_refresh() definition Ilya Dryomov
2023-10-05 15:29 ` [PATCH for 5.4 2/4] rbd: decouple header read-in from updating rbd_dev->header Ilya Dryomov
@ 2023-10-05 15:29 ` Ilya Dryomov
2023-10-05 15:29 ` [PATCH for 5.4 4/4] rbd: take header_rwsem in rbd_dev_refresh() only when updating Ilya Dryomov
3 siblings, 0 replies; 5+ messages in thread
From: Ilya Dryomov @ 2023-10-05 15:29 UTC (permalink / raw)
To: stable; +Cc: Greg KH, Dongsheng Yang
commit c10311776f0a8ddea2276df96e255625b07045a8 upstream.
Unlike header read-in, parent info read-in is already decoupled in
get_parent_info(), but it's buried in rbd_dev_v2_parent_info() along
with the processing logic.
Separate the initial read-in and update read-in logic into
rbd_dev_setup_parent() and rbd_dev_update_parent() respectively and
have rbd_dev_v2_parent_info() just populate struct parent_image_info
(i.e. what get_parent_info() did). Some existing QoI issues, like
flatten of a standalone clone being disregarded on refresh, remain.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Dongsheng Yang <dongsheng.yang@easystack.cn>
[idryomov@gmail.com: backport to 5.4: context]
---
drivers/block/rbd.c | 142 +++++++++++++++++++++++++-------------------
1 file changed, 80 insertions(+), 62 deletions(-)
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index 17d802effdc4..e86dca49fae7 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -5762,6 +5762,14 @@ struct parent_image_info {
u64 overlap;
};
+static void rbd_parent_info_cleanup(struct parent_image_info *pii)
+{
+ kfree(pii->pool_ns);
+ kfree(pii->image_id);
+
+ memset(pii, 0, sizeof(*pii));
+}
+
/*
* The caller is responsible for @pii.
*/
@@ -5831,6 +5839,9 @@ static int __get_parent_info(struct rbd_device *rbd_dev,
if (pii->has_overlap)
ceph_decode_64_safe(&p, end, pii->overlap, e_inval);
+ dout("%s pool_id %llu pool_ns %s image_id %s snap_id %llu has_overlap %d overlap %llu\n",
+ __func__, pii->pool_id, pii->pool_ns, pii->image_id, pii->snap_id,
+ pii->has_overlap, pii->overlap);
return 0;
e_inval:
@@ -5869,14 +5880,17 @@ static int __get_parent_info_legacy(struct rbd_device *rbd_dev,
pii->has_overlap = true;
ceph_decode_64_safe(&p, end, pii->overlap, e_inval);
+ dout("%s pool_id %llu pool_ns %s image_id %s snap_id %llu has_overlap %d overlap %llu\n",
+ __func__, pii->pool_id, pii->pool_ns, pii->image_id, pii->snap_id,
+ pii->has_overlap, pii->overlap);
return 0;
e_inval:
return -EINVAL;
}
-static int get_parent_info(struct rbd_device *rbd_dev,
- struct parent_image_info *pii)
+static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev,
+ struct parent_image_info *pii)
{
struct page *req_page, *reply_page;
void *p;
@@ -5904,7 +5918,7 @@ static int get_parent_info(struct rbd_device *rbd_dev,
return ret;
}
-static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev)
+static int rbd_dev_setup_parent(struct rbd_device *rbd_dev)
{
struct rbd_spec *parent_spec;
struct parent_image_info pii = { 0 };
@@ -5914,37 +5928,12 @@ static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev)
if (!parent_spec)
return -ENOMEM;
- ret = get_parent_info(rbd_dev, &pii);
+ ret = rbd_dev_v2_parent_info(rbd_dev, &pii);
if (ret)
goto out_err;
- dout("%s pool_id %llu pool_ns %s image_id %s snap_id %llu has_overlap %d overlap %llu\n",
- __func__, pii.pool_id, pii.pool_ns, pii.image_id, pii.snap_id,
- pii.has_overlap, pii.overlap);
-
- if (pii.pool_id == CEPH_NOPOOL || !pii.has_overlap) {
- /*
- * Either the parent never existed, or we have
- * record of it but the image got flattened so it no
- * longer has a parent. When the parent of a
- * layered image disappears we immediately set the
- * overlap to 0. The effect of this is that all new
- * requests will be treated as if the image had no
- * parent.
- *
- * If !pii.has_overlap, the parent image spec is not
- * applicable. It's there to avoid duplication in each
- * snapshot record.
- */
- if (rbd_dev->parent_overlap) {
- rbd_dev->parent_overlap = 0;
- rbd_dev_parent_put(rbd_dev);
- pr_info("%s: clone image has been flattened\n",
- rbd_dev->disk->disk_name);
- }
-
+ if (pii.pool_id == CEPH_NOPOOL || !pii.has_overlap)
goto out; /* No parent? No problem. */
- }
/* The ceph file layout needs to fit pool id in 32 bits */
@@ -5956,46 +5945,34 @@ static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev)
}
/*
- * The parent won't change (except when the clone is
- * flattened, already handled that). So we only need to
- * record the parent spec we have not already done so.
+ * The parent won't change except when the clone is flattened,
+ * so we only need to record the parent image spec once.
*/
- if (!rbd_dev->parent_spec) {
- parent_spec->pool_id = pii.pool_id;
- if (pii.pool_ns && *pii.pool_ns) {
- parent_spec->pool_ns = pii.pool_ns;
- pii.pool_ns = NULL;
- }
- parent_spec->image_id = pii.image_id;
- pii.image_id = NULL;
- parent_spec->snap_id = pii.snap_id;
-
- rbd_dev->parent_spec = parent_spec;
- parent_spec = NULL; /* rbd_dev now owns this */
+ parent_spec->pool_id = pii.pool_id;
+ if (pii.pool_ns && *pii.pool_ns) {
+ parent_spec->pool_ns = pii.pool_ns;
+ pii.pool_ns = NULL;
}
+ parent_spec->image_id = pii.image_id;
+ pii.image_id = NULL;
+ parent_spec->snap_id = pii.snap_id;
+
+ rbd_assert(!rbd_dev->parent_spec);
+ rbd_dev->parent_spec = parent_spec;
+ parent_spec = NULL; /* rbd_dev now owns this */
/*
- * We always update the parent overlap. If it's zero we issue
- * a warning, as we will proceed as if there was no parent.
+ * Record the parent overlap. If it's zero, issue a warning as
+ * we will proceed as if there is no parent.
*/
- if (!pii.overlap) {
- if (parent_spec) {
- /* refresh, careful to warn just once */
- if (rbd_dev->parent_overlap)
- rbd_warn(rbd_dev,
- "clone now standalone (overlap became 0)");
- } else {
- /* initial probe */
- rbd_warn(rbd_dev, "clone is standalone (overlap 0)");
- }
- }
+ if (!pii.overlap)
+ rbd_warn(rbd_dev, "clone is standalone (overlap 0)");
rbd_dev->parent_overlap = pii.overlap;
out:
ret = 0;
out_err:
- kfree(pii.pool_ns);
- kfree(pii.image_id);
+ rbd_parent_info_cleanup(&pii);
rbd_spec_put(parent_spec);
return ret;
}
@@ -6992,7 +6969,7 @@ static int rbd_dev_image_probe(struct rbd_device *rbd_dev, int depth)
}
if (rbd_dev->header.features & RBD_FEATURE_LAYERING) {
- ret = rbd_dev_v2_parent_info(rbd_dev);
+ ret = rbd_dev_setup_parent(rbd_dev);
if (ret)
goto err_out_probe;
}
@@ -7041,9 +7018,47 @@ static void rbd_dev_update_header(struct rbd_device *rbd_dev,
}
}
+static void rbd_dev_update_parent(struct rbd_device *rbd_dev,
+ struct parent_image_info *pii)
+{
+ if (pii->pool_id == CEPH_NOPOOL || !pii->has_overlap) {
+ /*
+ * Either the parent never existed, or we have
+ * record of it but the image got flattened so it no
+ * longer has a parent. When the parent of a
+ * layered image disappears we immediately set the
+ * overlap to 0. The effect of this is that all new
+ * requests will be treated as if the image had no
+ * parent.
+ *
+ * If !pii.has_overlap, the parent image spec is not
+ * applicable. It's there to avoid duplication in each
+ * snapshot record.
+ */
+ if (rbd_dev->parent_overlap) {
+ rbd_dev->parent_overlap = 0;
+ rbd_dev_parent_put(rbd_dev);
+ pr_info("%s: clone has been flattened\n",
+ rbd_dev->disk->disk_name);
+ }
+ } else {
+ rbd_assert(rbd_dev->parent_spec);
+
+ /*
+ * Update the parent overlap. If it became zero, issue
+ * a warning as we will proceed as if there is no parent.
+ */
+ if (!pii->overlap && rbd_dev->parent_overlap)
+ rbd_warn(rbd_dev,
+ "clone has become standalone (overlap 0)");
+ rbd_dev->parent_overlap = pii->overlap;
+ }
+}
+
static int rbd_dev_refresh(struct rbd_device *rbd_dev)
{
struct rbd_image_header header = { 0 };
+ struct parent_image_info pii = { 0 };
u64 mapping_size;
int ret;
@@ -7059,12 +7074,14 @@ static int rbd_dev_refresh(struct rbd_device *rbd_dev)
* mapped image getting flattened.
*/
if (rbd_dev->parent) {
- ret = rbd_dev_v2_parent_info(rbd_dev);
+ ret = rbd_dev_v2_parent_info(rbd_dev, &pii);
if (ret)
goto out;
}
rbd_dev_update_header(rbd_dev, &header);
+ if (rbd_dev->parent)
+ rbd_dev_update_parent(rbd_dev, &pii);
if (rbd_dev->spec->snap_id == CEPH_NOSNAP) {
rbd_dev->mapping.size = rbd_dev->header.image_size;
@@ -7078,6 +7095,7 @@ static int rbd_dev_refresh(struct rbd_device *rbd_dev)
if (!ret && mapping_size != rbd_dev->mapping.size)
rbd_dev_update_size(rbd_dev);
+ rbd_parent_info_cleanup(&pii);
rbd_image_header_cleanup(&header);
return ret;
}
--
2.41.0
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