powerpc/pseries: Update memory hotplug code to use drmem LMB array

Update the pseries memory hotplug code to use the newly added
dynamic reconfiguration LMB array. Doing this is required for the
upcoming support of version 2 of the dynamic reconfiguration
device tree property.

In addition, making this change cleans up the code that parses the
LMB information as we no longer need to worry about device tree
format. This allows us to discard one of the first steps on memory
hotplug where we make a working copy of the device tree property and
convert the entire property to cpu format. Instead we just use the
LMB array directly while holding the memory hotplug lock.

This patch also moves the updating of the device tree property to
powerpc/mm/drmem.c. This allows to the hotplug code to work without
needing to know the device tree format and provides a single
routine for updating the device tree property. This new routine
will handle determination of the proper device tree format and
generate a properly formatted device tree property.
Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/include/asm/drmem.h

@@ -40,9 +40,27 @@ static inline u32 drmem_lmb_size(void)
 	return drmem_info->lmb_size;
 }
 
+#define DRMEM_LMB_RESERVED	0x80000000
+
+static inline void drmem_mark_lmb_reserved(struct drmem_lmb *lmb)
+{
+	lmb->flags |= DRMEM_LMB_RESERVED;
+}
+
+static inline void drmem_remove_lmb_reservation(struct drmem_lmb *lmb)
+{
+	lmb->flags &= ~DRMEM_LMB_RESERVED;
+}
+
+static inline bool drmem_lmb_reserved(struct drmem_lmb *lmb)
+{
+	return lmb->flags & DRMEM_LMB_RESERVED;
+}
+
 u64 drmem_lmb_memory_max(void);
 void __init walk_drmem_lmbs(struct device_node *dn,
 			void (*func)(struct drmem_lmb *, const __be32 **));
+int drmem_update_dt(void);
 
 #ifdef CONFIG_PPC_PSERIES
 void __init walk_drmem_lmbs_early(unsigned long node,

arch/powerpc/mm/drmem.c

@@ -29,6 +29,87 @@ u64 drmem_lmb_memory_max(void)
 	return last_lmb->base_addr + drmem_lmb_size();
 }
 
+static u32 drmem_lmb_flags(struct drmem_lmb *lmb)
+{
+	/*
+	 * Return the value of the lmb flags field minus the reserved
+	 * bit used internally for hotplug processing.
+	 */
+	return lmb->flags & ~DRMEM_LMB_RESERVED;
+}
+
+static struct property *clone_property(struct property *prop, u32 prop_sz)
+{
+	struct property *new_prop;
+
+	new_prop = kzalloc(sizeof(*new_prop), GFP_KERNEL);
+	if (!new_prop)
+		return NULL;
+
+	new_prop->name = kstrdup(prop->name, GFP_KERNEL);
+	new_prop->value = kzalloc(prop_sz, GFP_KERNEL);
+	if (!new_prop->name || !new_prop->value) {
+		kfree(new_prop->name);
+		kfree(new_prop->value);
+		kfree(new_prop);
+		return NULL;
+	}
+
+	new_prop->length = prop_sz;
+#if defined(CONFIG_OF_DYNAMIC)
+	of_property_set_flag(new_prop, OF_DYNAMIC);
+#endif
+	return new_prop;
+}
+
+static int drmem_update_dt_v1(struct device_node *memory,
+			      struct property *prop)
+{
+	struct property *new_prop;
+	struct of_drconf_cell *dr_cell;
+	struct drmem_lmb *lmb;
+	u32 *p;
+
+	new_prop = clone_property(prop, prop->length);
+	if (!new_prop)
+		return -1;
+
+	p = new_prop->value;
+	*p++ = cpu_to_be32(drmem_info->n_lmbs);
+
+	dr_cell = (struct of_drconf_cell *)p;
+
+	for_each_drmem_lmb(lmb) {
+		dr_cell->base_addr = cpu_to_be64(lmb->base_addr);
+		dr_cell->drc_index = cpu_to_be32(lmb->drc_index);
+		dr_cell->aa_index = cpu_to_be32(lmb->aa_index);
+		dr_cell->flags = cpu_to_be32(drmem_lmb_flags(lmb));
+
+		dr_cell++;
+	}
+
+	of_update_property(memory, new_prop);
+	return 0;
+}
+
+int drmem_update_dt(void)
+{
+	struct device_node *memory;
+	struct property *prop;
+	int rc = -1;
+
+	memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
+	if (!memory)
+		return -1;
+
+	prop = of_find_property(memory, "ibm,dynamic-memory", NULL);
+	if (prop)
+		rc = drmem_update_dt_v1(memory, prop);
+
+	of_node_put(memory);
+	return rc;
+}
+
 static void __init read_drconf_v1_cell(struct drmem_lmb *lmb,
 				       const __be32 **prop)
 {

arch/powerpc/platforms/pseries/hotplug-memory.c

@@ -23,6 +23,7 @@
 #include <asm/prom.h>
 #include <asm/sparsemem.h>
 #include <asm/fadump.h>
+#include <asm/drmem.h>
 #include "pseries.h"
 
 static bool rtas_hp_event;
@@ -100,100 +101,6 @@ static struct property *dlpar_clone_property(struct property *prop,
 	return new_prop;
 }
 
-static struct property *dlpar_clone_drconf_property(struct device_node *dn)
-{
-	struct property *prop, *new_prop;
-	struct of_drconf_cell *lmbs;
-	u32 num_lmbs, *p;
-	int i;
-
-	prop = of_find_property(dn, "ibm,dynamic-memory", NULL);
-	if (!prop)
-		return NULL;
-
-	new_prop = dlpar_clone_property(prop, prop->length);
-	if (!new_prop)
-		return NULL;
-
-	/* Convert the property to cpu endian-ness */
-	p = new_prop->value;
-	*p = be32_to_cpu(*p);
-
-	num_lmbs = *p++;
-	lmbs = (struct of_drconf_cell *)p;
-
-	for (i = 0; i < num_lmbs; i++) {
-		lmbs[i].base_addr = be64_to_cpu(lmbs[i].base_addr);
-		lmbs[i].drc_index = be32_to_cpu(lmbs[i].drc_index);
-		lmbs[i].aa_index = be32_to_cpu(lmbs[i].aa_index);
-		lmbs[i].flags = be32_to_cpu(lmbs[i].flags);
-	}
-
-	return new_prop;
-}
-
-static void dlpar_update_drconf_property(struct device_node *dn,
-					 struct property *prop)
-{
-	struct of_drconf_cell *lmbs;
-	u32 num_lmbs, *p;
-	int i;
-
-	/* Convert the property back to BE */
-	p = prop->value;
-	num_lmbs = *p;
-	*p = cpu_to_be32(*p);
-	p++;
-
-	lmbs = (struct of_drconf_cell *)p;
-	for (i = 0; i < num_lmbs; i++) {
-		lmbs[i].base_addr = cpu_to_be64(lmbs[i].base_addr);
-		lmbs[i].drc_index = cpu_to_be32(lmbs[i].drc_index);
-		lmbs[i].aa_index = cpu_to_be32(lmbs[i].aa_index);
-		lmbs[i].flags = cpu_to_be32(lmbs[i].flags);
-	}
-
-	rtas_hp_event = true;
-	of_update_property(dn, prop);
-	rtas_hp_event = false;
-}
-
-static int dlpar_update_device_tree_lmb(struct of_drconf_cell *lmb)
-{
-	struct device_node *dn;
-	struct property *prop;
-	struct of_drconf_cell *lmbs;
-	u32 *p, num_lmbs;
-	int i;
-
-	dn = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
-	if (!dn)
-		return -ENODEV;
-
-	prop = dlpar_clone_drconf_property(dn);
-	if (!prop) {
-		of_node_put(dn);
-		return -ENODEV;
-	}
-
-	p = prop->value;
-	num_lmbs = *p++;
-	lmbs = (struct of_drconf_cell *)p;
-
-	for (i = 0; i < num_lmbs; i++) {
-		if (lmbs[i].drc_index == lmb->drc_index) {
-			lmbs[i].flags = lmb->flags;
-			lmbs[i].aa_index = lmb->aa_index;
-
-			dlpar_update_drconf_property(dn, prop);
-			break;
-		}
-	}
-
-	of_node_put(dn);
-	return 0;
-}
-
 static u32 find_aa_index(struct device_node *dr_node,
 			 struct property *ala_prop, const u32 *lmb_assoc)
 {
@@ -256,7 +163,7 @@ static u32 find_aa_index(struct device_node *dr_node,
 	return aa_index;
 }
 
-static u32 lookup_lmb_associativity_index(struct of_drconf_cell *lmb)
+static u32 lookup_lmb_associativity_index(struct drmem_lmb *lmb)
 {
 	struct device_node *parent, *lmb_node, *dr_node;
 	struct property *ala_prop;
@@ -299,9 +206,9 @@ static u32 lookup_lmb_associativity_index(struct of_drconf_cell *lmb)
 	return aa_index;
 }
 
-static int dlpar_add_device_tree_lmb(struct of_drconf_cell *lmb)
+static int dlpar_add_device_tree_lmb(struct drmem_lmb *lmb)
 {
-	int aa_index;
+	int rc, aa_index;
 
 	lmb->flags |= DRCONF_MEM_ASSIGNED;
 
@@ -313,17 +220,29 @@ static int dlpar_add_device_tree_lmb(struct of_drconf_cell *lmb)
 	}
 
 	lmb->aa_index = aa_index;
-	return dlpar_update_device_tree_lmb(lmb);
+
+	rtas_hp_event = true;
+	rc = drmem_update_dt();
+	rtas_hp_event = false;
+
+	return rc;
 }
 
-static int dlpar_remove_device_tree_lmb(struct of_drconf_cell *lmb)
+static int dlpar_remove_device_tree_lmb(struct drmem_lmb *lmb)
 {
+	int rc;
+
 	lmb->flags &= ~DRCONF_MEM_ASSIGNED;
 	lmb->aa_index = 0xffffffff;
-	return dlpar_update_device_tree_lmb(lmb);
+
+	rtas_hp_event = true;
+	rc = drmem_update_dt();
+	rtas_hp_event = false;
+
+	return rc;
 }
 
-static struct memory_block *lmb_to_memblock(struct of_drconf_cell *lmb)
+static struct memory_block *lmb_to_memblock(struct drmem_lmb *lmb)
 {
 	unsigned long section_nr;
 	struct mem_section *mem_sect;
@@ -336,7 +255,36 @@ static struct memory_block *lmb_to_memblock(struct of_drconf_cell *lmb)
 	return mem_block;
 }
 
-static int dlpar_change_lmb_state(struct of_drconf_cell *lmb, bool online)
+static int get_lmb_range(u32 drc_index, int n_lmbs,
+			 struct drmem_lmb **start_lmb,
+			 struct drmem_lmb **end_lmb)
+{
+	struct drmem_lmb *lmb, *start, *end;
+	struct drmem_lmb *last_lmb;
+
+	start = NULL;
+	for_each_drmem_lmb(lmb) {
+		if (lmb->drc_index == drc_index) {
+			start = lmb;
+			break;
+		}
+	}
+
+	if (!start)
+		return -EINVAL;
+
+	end = &start[n_lmbs - 1];
+
+	last_lmb = &drmem_info->lmbs[drmem_info->n_lmbs - 1];
+	if (end > last_lmb)
+		return -EINVAL;
+
+	*start_lmb = start;
+	*end_lmb = end;
+	return 0;
+}
+
+static int dlpar_change_lmb_state(struct drmem_lmb *lmb, bool online)
 {
 	struct memory_block *mem_block;
 	int rc;
@@ -357,13 +305,13 @@ static int dlpar_change_lmb_state(struct of_drconf_cell *lmb, bool online)
 	return rc;
 }
 
-static int dlpar_online_lmb(struct of_drconf_cell *lmb)
+static int dlpar_online_lmb(struct drmem_lmb *lmb)
 {
 	return dlpar_change_lmb_state(lmb, true);
 }
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
-static int dlpar_offline_lmb(struct of_drconf_cell *lmb)
+static int dlpar_offline_lmb(struct drmem_lmb *lmb)
 {
 	return dlpar_change_lmb_state(lmb, false);
 }
@@ -426,7 +374,7 @@ static int pseries_remove_mem_node(struct device_node *np)
 	return 0;
 }
 
-static bool lmb_is_removable(struct of_drconf_cell *lmb)
+static bool lmb_is_removable(struct drmem_lmb *lmb)
 {
 	int i, scns_per_block;
 	int rc = 1;
@@ -458,9 +406,9 @@ static bool lmb_is_removable(struct of_drconf_cell *lmb)
 	return rc ? true : false;
 }
 
-static int dlpar_add_lmb(struct of_drconf_cell *);
+static int dlpar_add_lmb(struct drmem_lmb *);
 
-static int dlpar_remove_lmb(struct of_drconf_cell *lmb)
+static int dlpar_remove_lmb(struct drmem_lmb *lmb)
 {
 	unsigned long block_sz;
 	int nid, rc;
@@ -484,28 +432,25 @@ static int dlpar_remove_lmb(struct of_drconf_cell *lmb)
 	return 0;
 }
 
-static int dlpar_memory_remove_by_count(u32 lmbs_to_remove,
-					struct property *prop)
+static int dlpar_memory_remove_by_count(u32 lmbs_to_remove)
 {
-	struct of_drconf_cell *lmbs;
+	struct drmem_lmb *lmb;
 	int lmbs_removed = 0;
 	int lmbs_available = 0;
-	u32 num_lmbs, *p;
-	int i, rc;
+	int rc;
 
 	pr_info("Attempting to hot-remove %d LMB(s)\n", lmbs_to_remove);
 
 	if (lmbs_to_remove == 0)
 		return -EINVAL;
 
-	p = prop->value;
-	num_lmbs = *p++;
-	lmbs = (struct of_drconf_cell *)p;
-
 	/* Validate that there are enough LMBs to satisfy the request */
-	for (i = 0; i < num_lmbs; i++) {
-		if (lmb_is_removable(&lmbs[i]))
+	for_each_drmem_lmb(lmb) {
+		if (lmb_is_removable(lmb))
 			lmbs_available++;
+
+		if (lmbs_available == lmbs_to_remove)
+			break;
 	}
 
 	if (lmbs_available < lmbs_to_remove) {
@@ -514,45 +459,47 @@ static int dlpar_memory_remove_by_count(u32 lmbs_to_remove,
 		return -EINVAL;
 	}
 
-	for (i = 0; i < num_lmbs && lmbs_removed < lmbs_to_remove; i++) {
-		rc = dlpar_remove_lmb(&lmbs[i]);
+	for_each_drmem_lmb(lmb) {
+		rc = dlpar_remove_lmb(lmb);
 		if (rc)
 			continue;
 
-		lmbs_removed++;
-
 		/* Mark this lmb so we can add it later if all of the
 		 * requested LMBs cannot be removed.
 		 */
-		lmbs[i].reserved = 1;
+		drmem_mark_lmb_reserved(lmb);
+
+		lmbs_removed++;
+		if (lmbs_removed == lmbs_to_remove)
+			break;
 	}
 
 	if (lmbs_removed != lmbs_to_remove) {
 		pr_err("Memory hot-remove failed, adding LMB's back\n");
 
-		for (i = 0; i < num_lmbs; i++) {
-			if (!lmbs[i].reserved)
+		for_each_drmem_lmb(lmb) {
+			if (!drmem_lmb_reserved(lmb))
 				continue;
 
-			rc = dlpar_add_lmb(&lmbs[i]);
+			rc = dlpar_add_lmb(lmb);
 			if (rc)
 				pr_err("Failed to add LMB back, drc index %x\n",
-				       lmbs[i].drc_index);
+				       lmb->drc_index);
 
-			lmbs[i].reserved = 0;
+			drmem_remove_lmb_reservation(lmb);
 		}
 
 		rc = -EINVAL;
 	} else {
-		for (i = 0; i < num_lmbs; i++) {
-			if (!lmbs[i].reserved)
+		for_each_drmem_lmb(lmb) {
+			if (!drmem_lmb_reserved(lmb))
 				continue;
 
-			dlpar_release_drc(lmbs[i].drc_index);
+			dlpar_release_drc(lmb->drc_index);
 			pr_info("Memory at %llx was hot-removed\n",
-				lmbs[i].base_addr);
+				lmb->base_addr);
 
-			lmbs[i].reserved = 0;
+			drmem_remove_lmb_reservation(lmb);
 		}
 		rc = 0;
 	}
@@ -560,26 +507,21 @@ static int dlpar_memory_remove_by_count(u32 lmbs_to_remove,
 	return rc;
 }
 
-static int dlpar_memory_remove_by_index(u32 drc_index, struct property *prop)
+static int dlpar_memory_remove_by_index(u32 drc_index)
 {
-	struct of_drconf_cell *lmbs;
-	u32 num_lmbs, *p;
+	struct drmem_lmb *lmb;
 	int lmb_found;
-	int i, rc;
+	int rc;
 
 	pr_info("Attempting to hot-remove LMB, drc index %x\n", drc_index);
 
-	p = prop->value;
-	num_lmbs = *p++;
-	lmbs = (struct of_drconf_cell *)p;
-
 	lmb_found = 0;
-	for (i = 0; i < num_lmbs; i++) {
-		if (lmbs[i].drc_index == drc_index) {
+	for_each_drmem_lmb(lmb) {
+		if (lmb->drc_index == drc_index) {
 			lmb_found = 1;
-			rc = dlpar_remove_lmb(&lmbs[i]);
+			rc = dlpar_remove_lmb(lmb);
 			if (!rc)
-				dlpar_release_drc(lmbs[i].drc_index);
+				dlpar_release_drc(lmb->drc_index);
 
 			break;
 		}
@@ -590,35 +532,30 @@ static int dlpar_memory_remove_by_index(u32 drc_index, struct property *prop)
 
 	if (rc)
 		pr_info("Failed to hot-remove memory at %llx\n",
-			lmbs[i].base_addr);
+			lmb->base_addr);
 	else
-		pr_info("Memory at %llx was hot-removed\n", lmbs[i].base_addr);
+		pr_info("Memory at %llx was hot-removed\n", lmb->base_addr);
 
 	return rc;
 }
 
-static int dlpar_memory_readd_by_index(u32 drc_index, struct property *prop)
+static int dlpar_memory_readd_by_index(u32 drc_index)
 {
-	struct of_drconf_cell *lmbs;
-	u32 num_lmbs, *p;
+	struct drmem_lmb *lmb;
 	int lmb_found;
-	int i, rc;
+	int rc;
 
 	pr_info("Attempting to update LMB, drc index %x\n", drc_index);
 
-	p = prop->value;
-	num_lmbs = *p++;
-	lmbs = (struct of_drconf_cell *)p;
-
 	lmb_found = 0;
-	for (i = 0; i < num_lmbs; i++) {
-		if (lmbs[i].drc_index == drc_index) {
+	for_each_drmem_lmb(lmb) {
+		if (lmb->drc_index == drc_index) {
 			lmb_found = 1;
-			rc = dlpar_remove_lmb(&lmbs[i]);
+			rc = dlpar_remove_lmb(lmb);
 			if (!rc) {
-				rc = dlpar_add_lmb(&lmbs[i]);
+				rc = dlpar_add_lmb(lmb);
 				if (rc)
-					dlpar_release_drc(lmbs[i].drc_index);
+					dlpar_release_drc(lmb->drc_index);
 			}
 			break;
 		}
@@ -629,20 +566,18 @@ static int dlpar_memory_readd_by_index(u32 drc_index, struct property *prop)
 
 	if (rc)
 		pr_info("Failed to update memory at %llx\n",
-			lmbs[i].base_addr);
+			lmb->base_addr);
 	else
-		pr_info("Memory at %llx was updated\n", lmbs[i].base_addr);
+		pr_info("Memory at %llx was updated\n", lmb->base_addr);
 
 	return rc;
 }
 
-static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index,
-				     struct property *prop)
+static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index)
 {
-	struct of_drconf_cell *lmbs;
-	u32 num_lmbs, *p;
-	int i, rc, start_lmb_found;
-	int lmbs_available = 0, start_index = 0, end_index;
+	struct drmem_lmb *lmb, *start_lmb, *end_lmb;
+	int lmbs_available = 0;
+	int rc;
 
 	pr_info("Attempting to hot-remove %u LMB(s) at %x\n",
 		lmbs_to_remove, drc_index);
@@ -650,29 +585,13 @@ static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index,
 	if (lmbs_to_remove == 0)
 		return -EINVAL;
 
-	p = prop->value;
-	num_lmbs = *p++;
-	lmbs = (struct of_drconf_cell *)p;
-	start_lmb_found = 0;
-
-	/* Navigate to drc_index */
-	while (start_index < num_lmbs) {
-		if (lmbs[start_index].drc_index == drc_index) {
-			start_lmb_found = 1;
-			break;
-		}
-
-		start_index++;
-	}
-
-	if (!start_lmb_found)
+	rc = get_lmb_range(drc_index, lmbs_to_remove, &start_lmb, &end_lmb);
+	if (rc)
 		return -EINVAL;
 
-	end_index = start_index + lmbs_to_remove;
-
 	/* Validate that there are enough LMBs to satisfy the request */
-	for (i = start_index; i < end_index; i++) {
-		if (lmbs[i].flags & DRCONF_MEM_RESERVED)
+	for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
+		if (lmb->flags & DRCONF_MEM_RESERVED)
 			break;
 
 		lmbs_available++;
@@ -681,42 +600,43 @@ static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index,
 	if (lmbs_available < lmbs_to_remove)
 		return -EINVAL;
 
-	for (i = start_index; i < end_index; i++) {
-		if (!(lmbs[i].flags & DRCONF_MEM_ASSIGNED))
+	for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
+		if (!(lmb->flags & DRCONF_MEM_ASSIGNED))
 			continue;
 
-		rc = dlpar_remove_lmb(&lmbs[i]);
+		rc = dlpar_remove_lmb(lmb);
 		if (rc)
 			break;
 
-		lmbs[i].reserved = 1;
+		drmem_mark_lmb_reserved(lmb);
 	}
 
 	if (rc) {
 		pr_err("Memory indexed-count-remove failed, adding any removed LMBs\n");
 
-		for (i = start_index; i < end_index; i++) {
-			if (!lmbs[i].reserved)
+
+		for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
+			if (!drmem_lmb_reserved(lmb))
 				continue;
 
-			rc = dlpar_add_lmb(&lmbs[i]);
+			rc = dlpar_add_lmb(lmb);
 			if (rc)
 				pr_err("Failed to add LMB, drc index %x\n",
-				       be32_to_cpu(lmbs[i].drc_index));
+				       lmb->drc_index);
 
-			lmbs[i].reserved = 0;
+			drmem_remove_lmb_reservation(lmb);
 		}
 		rc = -EINVAL;
 	} else {
-		for (i = start_index; i < end_index; i++) {
-			if (!lmbs[i].reserved)
+		for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
+			if (!drmem_lmb_reserved(lmb))
 				continue;
 
-			dlpar_release_drc(lmbs[i].drc_index);
+			dlpar_release_drc(lmb->drc_index);
 			pr_info("Memory at %llx (drc index %x) was hot-removed\n",
-				lmbs[i].base_addr, lmbs[i].drc_index);
+				lmb->base_addr, lmb->drc_index);
 
-			lmbs[i].reserved = 0;
+			drmem_remove_lmb_reservation(lmb);
 		}
 	}
 
@@ -737,32 +657,30 @@ static inline int dlpar_memory_remove(struct pseries_hp_errorlog *hp_elog)
 {
 	return -EOPNOTSUPP;
 }
-static int dlpar_remove_lmb(struct of_drconf_cell *lmb)
+static int dlpar_remove_lmb(struct drmem_lmb *lmb)
 {
 	return -EOPNOTSUPP;
 }
-static int dlpar_memory_remove_by_count(u32 lmbs_to_remove,
-					struct property *prop)
+static int dlpar_memory_remove_by_count(u32 lmbs_to_remove)
 {
 	return -EOPNOTSUPP;
 }
-static int dlpar_memory_remove_by_index(u32 drc_index, struct property *prop)
+static int dlpar_memory_remove_by_index(u32 drc_index)
 {
 	return -EOPNOTSUPP;
 }
-static int dlpar_memory_readd_by_index(u32 drc_index, struct property *prop)
+static int dlpar_memory_readd_by_index(u32 drc_index)
 {
 	return -EOPNOTSUPP;
 }
 
-static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index,
-				     struct property *prop)
+static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index)
 {
 	return -EOPNOTSUPP;
 }
 #endif /* CONFIG_MEMORY_HOTREMOVE */
 
-static int dlpar_add_lmb(struct of_drconf_cell *lmb)
+static int dlpar_add_lmb(struct drmem_lmb *lmb)
 {
 	unsigned long block_sz;
 	int nid, rc;
@@ -801,77 +719,79 @@ static int dlpar_add_lmb(struct of_drconf_cell *lmb)
 	return rc;
 }
 
-static int dlpar_memory_add_by_count(u32 lmbs_to_add, struct property *prop)
+static int dlpar_memory_add_by_count(u32 lmbs_to_add)
 {
-	struct of_drconf_cell *lmbs;
-	u32 num_lmbs, *p;
+	struct drmem_lmb *lmb;
 	int lmbs_available = 0;
 	int lmbs_added = 0;
-	int i, rc;
+	int rc;
 
 	pr_info("Attempting to hot-add %d LMB(s)\n", lmbs_to_add);
 
 	if (lmbs_to_add == 0)
 		return -EINVAL;
 
-	p = prop->value;
-	num_lmbs = *p++;
-	lmbs = (struct of_drconf_cell *)p;
-
 	/* Validate that there are enough LMBs to satisfy the request */
-	for (i = 0; i < num_lmbs; i++) {
-		if (!(lmbs[i].flags & DRCONF_MEM_ASSIGNED))
+	for_each_drmem_lmb(lmb) {
+		if (!(lmb->flags & DRCONF_MEM_ASSIGNED))
 			lmbs_available++;
+
+		if (lmbs_available == lmbs_to_add)
+			break;
 	}
 
 	if (lmbs_available < lmbs_to_add)
 		return -EINVAL;
 
-	for (i = 0; i < num_lmbs && lmbs_to_add != lmbs_added; i++) {
-		if (lmbs[i].flags & DRCONF_MEM_ASSIGNED)
+	for_each_drmem_lmb(lmb) {
+		if (lmb->flags & DRCONF_MEM_ASSIGNED)
 			continue;
 
-		rc = dlpar_acquire_drc(lmbs[i].drc_index);
+		rc = dlpar_acquire_drc(lmb->drc_index);
 		if (rc)
 			continue;
 
-		rc = dlpar_add_lmb(&lmbs[i]);
+		rc = dlpar_add_lmb(lmb);
 		if (rc) {
-			dlpar_release_drc(lmbs[i].drc_index);
+			dlpar_release_drc(lmb->drc_index);
 			continue;
 		}
 
-		lmbs_added++;
-
 		/* Mark this lmb so we can remove it later if all of the
 		 * requested LMBs cannot be added.
 		 */
-		lmbs[i].reserved = 1;
+		drmem_mark_lmb_reserved(lmb);
+
+		lmbs_added++;
+		if (lmbs_added == lmbs_to_add)
+			break;
 	}
 
 	if (lmbs_added != lmbs_to_add) {
 		pr_err("Memory hot-add failed, removing any added LMBs\n");
 
-		for (i = 0; i < num_lmbs; i++) {
-			if (!lmbs[i].reserved)
+		for_each_drmem_lmb(lmb) {
+			if (!drmem_lmb_reserved(lmb))
 				continue;
 
-			rc = dlpar_remove_lmb(&lmbs[i]);
+			rc = dlpar_remove_lmb(lmb);
 			if (rc)
 				pr_err("Failed to remove LMB, drc index %x\n",
-				       be32_to_cpu(lmbs[i].drc_index));
+				       lmb->drc_index);
 			else
-				dlpar_release_drc(lmbs[i].drc_index);
+				dlpar_release_drc(lmb->drc_index);
+
+			drmem_remove_lmb_reservation(lmb);
 		}
 		rc = -EINVAL;
 	} else {
-		for (i = 0; i < num_lmbs; i++) {
-			if (!lmbs[i].reserved)
+		for_each_drmem_lmb(lmb) {
+			if (!drmem_lmb_reserved(lmb))
 				continue;
 
 			pr_info("Memory at %llx (drc index %x) was hot-added\n",
-				lmbs[i].base_addr, lmbs[i].drc_index);
-			lmbs[i].reserved = 0;
+				lmb->base_addr, lmb->drc_index);
+			drmem_remove_lmb_reservation(lmb);
 		}
 		rc = 0;
 	}
@@ -879,28 +799,22 @@ static int dlpar_memory_add_by_count(u32 lmbs_to_add, struct property *prop)
 	return rc;
 }
 
-static int dlpar_memory_add_by_index(u32 drc_index, struct property *prop)
+static int dlpar_memory_add_by_index(u32 drc_index)
 {
-	struct of_drconf_cell *lmbs;
-	u32 num_lmbs, *p;
-	int i, lmb_found;
-	int rc;
+	struct drmem_lmb *lmb;
+	int rc, lmb_found;
 
 	pr_info("Attempting to hot-add LMB, drc index %x\n", drc_index);
 
-	p = prop->value;
-	num_lmbs = *p++;
-	lmbs = (struct of_drconf_cell *)p;
-
 	lmb_found = 0;
-	for (i = 0; i < num_lmbs; i++) {
-		if (lmbs[i].drc_index == drc_index) {
+	for_each_drmem_lmb(lmb) {
+		if (lmb->drc_index == drc_index) {
 			lmb_found = 1;
-			rc = dlpar_acquire_drc(lmbs[i].drc_index);
+			rc = dlpar_acquire_drc(lmb->drc_index);
 			if (!rc) {
-				rc = dlpar_add_lmb(&lmbs[i]);
+				rc = dlpar_add_lmb(lmb);
 				if (rc)
-					dlpar_release_drc(lmbs[i].drc_index);
+					dlpar_release_drc(lmb->drc_index);
 			}
 
 			break;
@@ -914,18 +828,16 @@ static int dlpar_memory_add_by_index(u32 drc_index, struct property *prop)
 		pr_info("Failed to hot-add memory, drc index %x\n", drc_index);
 	else
 		pr_info("Memory at %llx (drc index %x) was hot-added\n",
-			lmbs[i].base_addr, drc_index);
+			lmb->base_addr, drc_index);
 
 	return rc;
 }
 
-static int dlpar_memory_add_by_ic(u32 lmbs_to_add, u32 drc_index,
-				  struct property *prop)
+static int dlpar_memory_add_by_ic(u32 lmbs_to_add, u32 drc_index)
 {
-	struct of_drconf_cell *lmbs;
-	u32 num_lmbs, *p;
-	int i, rc, start_lmb_found;
-	int lmbs_available = 0, start_index = 0, end_index;
+	struct drmem_lmb *lmb, *start_lmb, *end_lmb;
+	int lmbs_available = 0;
+	int rc;
 
 	pr_info("Attempting to hot-add %u LMB(s) at index %x\n",
 		lmbs_to_add, drc_index);
@@ -933,29 +845,13 @@ static int dlpar_memory_add_by_ic(u32 lmbs_to_add, u32 drc_index,
 	if (lmbs_to_add == 0)
 		return -EINVAL;
 
-	p = prop->value;
-	num_lmbs = *p++;
-	lmbs = (struct of_drconf_cell *)p;
-	start_lmb_found = 0;
-
-	/* Navigate to drc_index */
-	while (start_index < num_lmbs) {
-		if (lmbs[start_index].drc_index == drc_index) {
-			start_lmb_found = 1;
-			break;
-		}
-
-		start_index++;
-	}
-
-	if (!start_lmb_found)
+	rc = get_lmb_range(drc_index, lmbs_to_add, &start_lmb, &end_lmb);
+	if (rc)
 		return -EINVAL;
 
-	end_index = start_index + lmbs_to_add;
-
 	/* Validate that the LMBs in this range are not reserved */
-	for (i = start_index; i < end_index; i++) {
-		if (lmbs[i].flags & DRCONF_MEM_RESERVED)
+	for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
+		if (lmb->flags & DRCONF_MEM_RESERVED)
 			break;
 
 		lmbs_available++;
@@ -964,46 +860,48 @@ static int dlpar_memory_add_by_ic(u32 lmbs_to_add, u32 drc_index,
 	if (lmbs_available < lmbs_to_add)
 		return -EINVAL;
 
-	for (i = start_index; i < end_index; i++) {
-		if (lmbs[i].flags & DRCONF_MEM_ASSIGNED)
+	for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
+		if (lmb->flags & DRCONF_MEM_ASSIGNED)
 			continue;
 
-		rc = dlpar_acquire_drc(lmbs[i].drc_index);
+		rc = dlpar_acquire_drc(lmb->drc_index);
 		if (rc)
 			break;
 
-		rc = dlpar_add_lmb(&lmbs[i]);
+		rc = dlpar_add_lmb(lmb);
 		if (rc) {
-			dlpar_release_drc(lmbs[i].drc_index);
+			dlpar_release_drc(lmb->drc_index);
 			break;
 		}
 
-		lmbs[i].reserved = 1;
+		drmem_mark_lmb_reserved(lmb);
 	}
 
 	if (rc) {
 		pr_err("Memory indexed-count-add failed, removing any added LMBs\n");
 
-		for (i = start_index; i < end_index; i++) {
-			if (!lmbs[i].reserved)
+		for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
+			if (!drmem_lmb_reserved(lmb))
 				continue;
 
-			rc = dlpar_remove_lmb(&lmbs[i]);
+			rc = dlpar_remove_lmb(lmb);
 			if (rc)
 				pr_err("Failed to remove LMB, drc index %x\n",
-				       be32_to_cpu(lmbs[i].drc_index));
+				       lmb->drc_index);
 			else
-				dlpar_release_drc(lmbs[i].drc_index);
+				dlpar_release_drc(lmb->drc_index);
+
+			drmem_remove_lmb_reservation(lmb);
 		}
 		rc = -EINVAL;
 	} else {
-		for (i = start_index; i < end_index; i++) {
-			if (!lmbs[i].reserved)
+		for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
+			if (!drmem_lmb_reserved(lmb))
 				continue;
 
 			pr_info("Memory at %llx (drc index %x) was hot-added\n",
-				lmbs[i].base_addr, lmbs[i].drc_index);
-			lmbs[i].reserved = 0;
+				lmb->base_addr, lmb->drc_index);
+			drmem_remove_lmb_reservation(lmb);
 		}
 	}
 
@@ -1012,37 +910,23 @@ static int dlpar_memory_add_by_ic(u32 lmbs_to_add, u32 drc_index,
 
 int dlpar_memory(struct pseries_hp_errorlog *hp_elog)
 {
-	struct device_node *dn;
-	struct property *prop;
 	u32 count, drc_index;
 	int rc;
 
 	lock_device_hotplug();
 
-	dn = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
-	if (!dn) {
-		rc = -EINVAL;
-		goto dlpar_memory_out;
-	}
-
-	prop = dlpar_clone_drconf_property(dn);
-	if (!prop) {
-		rc = -EINVAL;
-		goto dlpar_memory_out;
-	}
-
 	switch (hp_elog->action) {
 	case PSERIES_HP_ELOG_ACTION_ADD:
 		if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_COUNT) {
 			count = hp_elog->_drc_u.drc_count;
-			rc = dlpar_memory_add_by_count(count, prop);
+			rc = dlpar_memory_add_by_count(count);
 		} else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_INDEX) {
 			drc_index = hp_elog->_drc_u.drc_index;
-			rc = dlpar_memory_add_by_index(drc_index, prop);
+			rc = dlpar_memory_add_by_index(drc_index);
 		} else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_IC) {
 			count = hp_elog->_drc_u.ic.count;
 			drc_index = hp_elog->_drc_u.ic.index;
-			rc = dlpar_memory_add_by_ic(count, drc_index, prop);
+			rc = dlpar_memory_add_by_ic(count, drc_index);
 		} else {
 			rc = -EINVAL;
 		}
@@ -1051,14 +935,14 @@ int dlpar_memory(struct pseries_hp_errorlog *hp_elog)
 	case PSERIES_HP_ELOG_ACTION_REMOVE:
 		if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_COUNT) {
 			count = hp_elog->_drc_u.drc_count;
-			rc = dlpar_memory_remove_by_count(count, prop);
+			rc = dlpar_memory_remove_by_count(count);
 		} else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_INDEX) {
 			drc_index = hp_elog->_drc_u.drc_index;
-			rc = dlpar_memory_remove_by_index(drc_index, prop);
+			rc = dlpar_memory_remove_by_index(drc_index);
 		} else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_IC) {
 			count = hp_elog->_drc_u.ic.count;
 			drc_index = hp_elog->_drc_u.ic.index;
-			rc = dlpar_memory_remove_by_ic(count, drc_index, prop);
+			rc = dlpar_memory_remove_by_ic(count, drc_index);
 		} else {
 			rc = -EINVAL;
 		}
@@ -1066,7 +950,7 @@ int dlpar_memory(struct pseries_hp_errorlog *hp_elog)
 		break;
 	case PSERIES_HP_ELOG_ACTION_READD:
 		drc_index = hp_elog->_drc_u.drc_index;
-		rc = dlpar_memory_readd_by_index(drc_index, prop);
+		rc = dlpar_memory_readd_by_index(drc_index);
 		break;
 	default:
 		pr_err("Invalid action (%d) specified\n", hp_elog->action);
@@ -1074,10 +958,6 @@ int dlpar_memory(struct pseries_hp_errorlog *hp_elog)
 		break;
 	}
 
-	dlpar_free_property(prop);
-
-dlpar_memory_out:
-	of_node_put(dn);
 	unlock_device_hotplug();
 	return rc;
 }