[Powerpc-utils-devel] [PATCH] drmgr: Memory kernel dlpar

[Nathan F. <nf...@au...>]

This patch enables drmgr to do DLPAR operations for memory
on systems that can do the acquisition via rtas and device tree
updating in the kernel.

NOTE: This patch depends on the DLPAR infrastructure patch set posted
to linuxppc-dev.

Signed-off-by: Nathan Fontenot <nf...@au...>
---

Index: powerpc-utils/src/drmgr/drmem.h
===================================================================
--- powerpc-utils.orig/src/drmgr/drmem.h	2009-09-15 13:30:26.000000000 -0500
+++ powerpc-utils/src/drmgr/drmem.h	2009-09-15 13:37:40.000000000 -0500
@@ -19,6 +19,7 @@
 #define DRMEM_DRC_INVALID	0x00000020
 
 #define MEM_PROBE_FILE		"/sys/devices/system/memory/probe"
+#define MEM_RELEASE_FILE	"/sys/devices/system/memory/release"
 #define MEM_BLOCK_SIZE_BYTES	"/sys/devices/system/memory/block_size_bytes"
 #define DYNAMIC_RECONFIG_MEM	"/proc/device-tree/ibm,dynamic-reconfiguration-memory"
 
Index: powerpc-utils/src/drmgr/drslot_chrp_mem.c
===================================================================
--- powerpc-utils.orig/src/drmgr/drslot_chrp_mem.c	2009-09-15 13:30:26.000000000 -0500
+++ powerpc-utils/src/drmgr/drslot_chrp_mem.c	2009-09-15 13:39:32.000000000 -0500
@@ -35,6 +35,16 @@
 	*pusage = usagestr;
 }
 
+static int
+is_kernel_dlpar_capable(void)
+{
+	struct stat sbuf;
+	int rc;
+
+	rc = stat(MEM_RELEASE_FILE, &sbuf);
+	return !rc;
+}
+
 /**
  * get_phandle
  *
@@ -302,13 +312,13 @@
 		if (drmem->flags & DRMEM_ASSIGNED) {
 			found++;
 			lmb->is_owned = 1;
-
-			/* find the associated sysfs memory blocks */
-			rc = get_mem_scns(lmb);
-			if (rc)
-				break;
 		}
 
+		/* find the associated sysfs memory blocks */
+		rc = get_mem_scns(lmb);
+		if (rc)
+			break;
+
 		drmem++; /* trust your compiler */
 	}
 
@@ -756,6 +766,34 @@
 	return 0;
 }
 
+static int
+release_lmb(struct dr_node *lmb)
+{
+	char buf[DR_STR_MAX];
+	int release_file;
+	int write_len;
+	int rc;
+
+	release_file = open(MEM_RELEASE_FILE, O_WRONLY);
+	if (release_file <= 0) {
+		dbg("Could not open %s to release lmb\n", MEM_RELEASE_FILE);
+		return errno;
+	}
+
+	memset(buf, 0, DR_STR_MAX);
+	write_len = sprintf(buf, "0x%x", lmb->drc_index);
+	rc = write(release_file, buf, write_len);
+	if (rc != write_len)
+		dbg("Write to %s failed!\n%s\n", MEM_RELEASE_FILE,
+		    strerror(errno));
+	else
+		/* reset rc to success */
+		rc = 0;
+
+	close(release_file);
+	return rc;
+}
+
 /**
  * set_lmb_state
  *
@@ -818,6 +856,7 @@
 {
 	int rc = 0;
 	struct dr_node *lmb;
+	int kernel_dlpar_capable = is_kernel_dlpar_capable();
 
 	lmb_list->lmbs_modified = 0;
 	while (lmb_list->lmbs_modified < (int)opts->quantity) {
@@ -825,23 +864,28 @@
 		if (lmb == NULL)
 			return -1;
 
-		rc = acquire_drc(lmb->drc_index);
-		if (rc) {
-			lmb->unusable = 1;
-			continue;
-		}
+		if (!kernel_dlpar_capable) {
+			rc = acquire_drc(lmb->drc_index);
+			if (rc) {
+				lmb->unusable = 1;
+				continue;
+			}
 
-		rc = add_device_tree_lmb(lmb, lmb_list);
-		if (rc) {
-			release_drc(lmb->drc_index, MEM_DEV);
-			lmb->unusable = 1;
-			continue;
+			rc = add_device_tree_lmb(lmb, lmb_list);
+			if (rc) {
+				release_drc(lmb->drc_index, MEM_DEV);
+				lmb->unusable = 1;
+				continue;
+			}
 		}
 
 		rc = set_lmb_state(lmb, ONLINE);
 		if (rc) {
-			remove_device_tree_lmb(lmb, lmb_list);
-			release_drc(lmb->drc_index, MEM_DEV);
+			if (!kernel_dlpar_capable) {
+				remove_device_tree_lmb(lmb, lmb_list);
+				release_drc(lmb->drc_index, MEM_DEV);
+			}
+
 			lmb->unusable = 1;
 			continue;
 		}
@@ -893,6 +937,7 @@
 {
 	struct dr_node *lmb;
 	int rc;
+	int kernel_dlpar_capable = is_kernel_dlpar_capable();
 
 	while (lmb_list->lmbs_modified < (int)opts->quantity) {
 		lmb = get_available_lmb(opts, lmb_list);
@@ -905,25 +950,33 @@
 			continue;
 		}
 
-		rc = remove_device_tree_lmb(lmb, lmb_list);
-		if (rc) {
-			set_lmb_state(lmb, ONLINE);
-			lmb->unusable = 1;
-			continue;
-		}
+		if (kernel_dlpar_capable) {
+			rc = release_lmb(lmb);
+			if (rc) {
+				lmb->unusable = 1;
+				continue;
+			}
+		} else {
+			rc = remove_device_tree_lmb(lmb, lmb_list);
+			if (rc) {
+				set_lmb_state(lmb, ONLINE);
+				lmb->unusable = 1;
+				continue;
+			}
 
-		while (lmb->lmb_mem_scns) {
-			struct mem_scn *scn = lmb->lmb_mem_scns;
-			lmb->lmb_mem_scns = scn->next;
-			free(scn);
-		}
+			while (lmb->lmb_mem_scns) {
+				struct mem_scn *scn = lmb->lmb_mem_scns;
+				lmb->lmb_mem_scns = scn->next;
+				free(scn);
+			}
 
-		rc = release_drc(lmb->drc_index, 0);
-		if (rc) {
-			add_device_tree_lmb(lmb, lmb_list);
-			set_lmb_state(lmb, ONLINE);
-			lmb->unusable = 1;
-			continue;
+			rc = release_drc(lmb->drc_index, 0);
+			if (rc) {
+				add_device_tree_lmb(lmb, lmb_list);
+				set_lmb_state(lmb, ONLINE);
+				lmb->unusable = 1;
+				continue;
+			}
 		}
 
 		lmb->is_removable = 0;