[ndctl] libndctl/inject: Refuse error injection for BTT namespaces

Commit Message

Verma, Vishal L June 14, 2019, 6:52 p.m. UTC

Error injection on a BTT namespace would treat the namespace as 'raw'
for the purposes of the injection. This can be useful for development,
but to a user this can be surprising, as injecting with --block=1 would
corrupt the BTT info block, and the BTT would be lost.

The unit tests do not rely on injecting errors directly into a BTT
namespace - they convert the namespace to 'raw' mode before performing
such an injection. For development and testing purposes, we will still
retain this ability by enforcing that the BTT namespace be explicitly
forced into raw mode before injection.

Reported-by: Marek de Rosier <[e-mail]>
Reported-by: Dan Williams <[e-mail]>
Signed-off-by: Vishal Verma <[e-mail]>
---
 ndctl/lib/inject.c | 33 ++++++++++++++++++++++++---------
 1 file changed, 24 insertions(+), 9 deletions(-)

Comments

Dan Williams June 14, 2019, 7:52 p.m. UTC | #1

On Fri, Jun 14, 2019 at 11:52 AM Vishal Verma <[e-mail]> wrote:
>
> Error injection on a BTT namespace would treat the namespace as 'raw'
> for the purposes of the injection. This can be useful for development,
> but to a user this can be surprising, as injecting with --block=1 would
> corrupt the BTT info block, and the BTT would be lost.
>
> The unit tests do not rely on injecting errors directly into a BTT
> namespace - they convert the namespace to 'raw' mode before performing
> such an injection. For development and testing purposes, we will still
> retain this ability by enforcing that the BTT namespace be explicitly
> forced into raw mode before injection.
>
> Reported-by: Marek de Rosier <[e-mail]>
> Reported-by: Dan Williams <[e-mail]>
> Signed-off-by: Vishal Verma <[e-mail]>

Looks good,

Reviewed-by: Dan Williams <[e-mail]>

Patch

diff --git a/ndctl/lib/inject.c b/ndctl/lib/inject.c
index c35d0f3..815f254 100644
--- a/ndctl/lib/inject.c
+++ b/ndctl/lib/inject.c
@@ -34,28 +34,36 @@  NDCTL_EXPORT int ndctl_bus_has_error_injection(struct ndctl_bus *bus)
 	return 0;
 }
 
-static void ndctl_namespace_get_injection_bounds(
+static int ndctl_namespace_get_injection_bounds(
 		struct ndctl_namespace *ndns, unsigned long long *ns_offset,
 		unsigned long long *ns_size)
 {
 	struct ndctl_pfn *pfn = ndctl_namespace_get_pfn(ndns);
 	struct ndctl_dax *dax = ndctl_namespace_get_dax(ndns);
+	struct ndctl_btt *btt = ndctl_namespace_get_btt(ndns);
 
 	if (!ns_offset || !ns_size)
-		return;
+		return -ENXIO;
 
 	if (pfn) {
 		*ns_offset = ndctl_pfn_get_resource(pfn);
 		*ns_size = ndctl_pfn_get_size(pfn);
-		return;
-	} else if (dax) {
+		return 0;
+	}
+
+	if (dax) {
 		*ns_offset = ndctl_dax_get_resource(dax);
 		*ns_size = ndctl_dax_get_size(dax);
-		return;
+		return 0;
 	}
-	/* raw or btt */
+
+	if (btt)
+		return -EOPNOTSUPP;
+
+	/* raw */
 	*ns_offset = ndctl_namespace_get_resource(ndns);
 	*ns_size = ndctl_namespace_get_size(ndns);
+	return 0;
 }
 
 static int block_to_spa_offset(struct ndctl_namespace *ndns,
@@ -64,8 +72,11 @@  static int block_to_spa_offset(struct ndctl_namespace *ndns,
 {
 	struct ndctl_ctx *ctx = ndctl_namespace_get_ctx(ndns);
 	unsigned long long ns_offset, ns_size;
+	int rc;
 
-	ndctl_namespace_get_injection_bounds(ndns, &ns_offset, &ns_size);
+	rc = ndctl_namespace_get_injection_bounds(ndns, &ns_offset, &ns_size);
+	if (rc)
+		return rc;
 	*offset = ns_offset + block * 512;
 	*length = count * 512;
 
@@ -98,8 +109,10 @@  static int ndctl_namespace_get_clear_unit(struct ndctl_namespace *ndns)
 	struct ndctl_cmd *cmd;
 	int rc;
 
-	ndctl_namespace_get_injection_bounds(ndns, &ns_offset,
+	rc = ndctl_namespace_get_injection_bounds(ndns, &ns_offset,
 		&ns_size);
+	if (rc)
+		return rc;
 	cmd = ndctl_bus_cmd_new_ars_cap(bus, ns_offset, ns_size);
 	rc = ndctl_cmd_submit(cmd);
 	if (rc < 0) {
@@ -438,8 +451,10 @@  NDCTL_EXPORT int ndctl_namespace_injection_status(struct ndctl_namespace *ndns)
 		return -EOPNOTSUPP;
 
 	if (ndctl_bus_has_nfit(bus)) {
-		ndctl_namespace_get_injection_bounds(ndns, &ns_offset,
+		rc = ndctl_namespace_get_injection_bounds(ndns, &ns_offset,
 			&ns_size);
+		if (rc)
+			return rc;
 
 		cmd = ndctl_bus_cmd_new_ars_cap(bus, ns_offset, ns_size);
 		rc = ndctl_cmd_submit(cmd);