diff mbox series

[ndctl,v2,1/2] libcxl: Add memdev inject & clear poison support

Message ID 20230517032311.19923-2-junhyeok.im@samsung.com
State New, archived
Headers show
Series Support for inject and clear poison | expand

Commit Message

Junhyeok Im May 17, 2023, 3:23 a.m. UTC 
Add abilities to inject and clear poison to memdev based on the debugfs
(/sys/kernel/debug/cxl/memX/{inject_/clear_}poison) interfaces that target
kernel v6.4[1].

These interfaces trigger inject/clear poison function by writing DPA to the
memory device debugfs attributes.

In order to write the DPA in the debugfs attribute, 'sysfs_write_attr' macro
is used which already defined.

Signed-off-by: Junhyeok Im <junhyeok.im@samsung.com>

[1] https://lore.kernel.org/linux-cxl/cover.1681874357.git.alison.schofield@intel.com/
---
 Documentation/cxl/lib/libcxl.txt |  5 +++
 cxl/lib/libcxl.c                 | 53 ++++++++++++++++++++++++++++++++
 cxl/lib/libcxl.sym               |  6 ++++
 cxl/libcxl.h                     |  2 ++
 4 files changed, 66 insertions(+)
diff mbox series

Patch

diff --git a/Documentation/cxl/lib/libcxl.txt b/Documentation/cxl/lib/libcxl.txt
index 31bc855..24a2535 100644
--- a/Documentation/cxl/lib/libcxl.txt
+++ b/Documentation/cxl/lib/libcxl.txt
@@ -132,6 +132,8 @@  int cxl_memdev_read_label(struct cxl_memdev *memdev, void *buf, size_t length,
 			  size_t offset);
 int cxl_memdev_write_label(struct cxl_memdev *memdev, void *buf, size_t length,
 			   size_t offset);
+int cxl_memdev_inject_poison(struct cxl_memdev *memdev, const char *address);
+int cxl_memdev_clear_poison(struct cxl_memdev *memdev, const char *address);
 struct cxl_cmd *cxl_cmd_new_get_partition(struct cxl_memdev *memdev);
 struct cxl_cmd *cxl_cmd_new_set_partition(struct cxl_memdev *memdev,
 					  unsigned long long volatile_size);
@@ -172,6 +174,9 @@  cxl_memdev{read,write,zero}_label() are helpers for marshaling multiple
 label access commands over an arbitrary extent of the device's label
 area.
 
+cxl_memdev_{inject,clear}_poison() support injecting/clearing poison
+into/from a physical address on a specified CXL memory device.
+
 cxl_cmd_partition_set_mode() supports selecting NEXTBOOT or IMMEDIATE
 mode. When CXL_SETPART_IMMEDIATE mode is set, it is the caller’s
 responsibility to avoid immediate changes to partitioning when the
diff --git a/cxl/lib/libcxl.c b/cxl/lib/libcxl.c
index 769cd8a..b2d0642 100644
--- a/cxl/lib/libcxl.c
+++ b/cxl/lib/libcxl.c
@@ -1458,6 +1458,59 @@  CXL_EXPORT int cxl_memdev_enable(struct cxl_memdev *memdev)
 	return 0;
 }
 
+#define PATH_DEBUG_FS "/sys/kernel/debug/cxl"
+CXL_EXPORT int cxl_memdev_inject_poison(struct cxl_memdev *memdev,
+					const char *address)
+{
+	struct cxl_ctx *ctx = cxl_memdev_get_ctx(memdev);
+	char *path = memdev->dev_buf;
+	int len = memdev->buf_len, rc;
+
+	if (snprintf(path, len, "%s/%s/inject_poison", PATH_DEBUG_FS,
+		     cxl_memdev_get_devname(memdev)) >= len) {
+		err(ctx, "%s: buffer too small\n",
+		    cxl_memdev_get_devname(memdev));
+		return -ENXIO;
+	}
+	rc = sysfs_write_attr(ctx, path, address);
+	if (rc < 0) {
+		err(ctx, "%s: failed to inject poison\n",
+		    cxl_memdev_get_devname(memdev));
+		return rc;
+	}
+
+	dbg(ctx, "%s: poison injected at %s\n", cxl_memdev_get_devname(memdev),
+	    address);
+
+	return 0;
+}
+
+CXL_EXPORT int cxl_memdev_clear_poison(struct cxl_memdev *memdev,
+				       const char *address)
+{
+	struct cxl_ctx *ctx = cxl_memdev_get_ctx(memdev);
+	char *path = memdev->dev_buf;
+	int len = memdev->buf_len, rc;
+
+	if (snprintf(path, len, "%s/%s/clear_poison", PATH_DEBUG_FS,
+		     cxl_memdev_get_devname(memdev)) >= len) {
+		err(ctx, "%s: buffer too small\n",
+		    cxl_memdev_get_devname(memdev));
+		return -ENXIO;
+	}
+	rc = sysfs_write_attr(ctx, path, address);
+	if (rc < 0) {
+		err(ctx, "%s: failed to clear poison\n",
+		    cxl_memdev_get_devname(memdev));
+		return rc;
+	}
+
+	dbg(ctx, "%s: poison cleared at %s\n", cxl_memdev_get_devname(memdev),
+	    address);
+
+	return 0;
+}
+
 static struct cxl_endpoint *
 cxl_port_recurse_endpoint(struct cxl_port *parent_port,
 			  struct cxl_memdev *memdev)
diff --git a/cxl/lib/libcxl.sym b/cxl/lib/libcxl.sym
index c6545c7..0f312a5 100644
--- a/cxl/lib/libcxl.sym
+++ b/cxl/lib/libcxl.sym
@@ -250,3 +250,9 @@  global:
 	cxl_region_get_daxctl_region;
 	cxl_port_get_parent_dport;
 } LIBCXL_4;
+
+LIBCXL_6 {
+global:
+	cxl_memdev_inject_poison;
+	cxl_memdev_clear_poison;
+} LIBCXL_5;
diff --git a/cxl/libcxl.h b/cxl/libcxl.h
index 0218d73..e3b2524 100644
--- a/cxl/libcxl.h
+++ b/cxl/libcxl.h
@@ -68,6 +68,8 @@  int cxl_memdev_read_label(struct cxl_memdev *memdev, void *buf, size_t length,
 		size_t offset);
 int cxl_memdev_write_label(struct cxl_memdev *memdev, void *buf, size_t length,
 		size_t offset);
+int cxl_memdev_inject_poison(struct cxl_memdev *memdev, const char *address);
+int cxl_memdev_clear_poison(struct cxl_memdev *memdev, const char *address);
 
 #define cxl_memdev_foreach(ctx, memdev) \
         for (memdev = cxl_memdev_get_first(ctx); \