arch/powerpc/platforms/pseries/hotplug-memory.c - linux/kernel/git/bpf/bpf - Git at Google

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * pseries Memory Hotplug infrastructure.
  *
  * Copyright (C) 2008 Badari Pulavarty, IBM Corporation
  */

 #define pr_fmt(fmt)	"pseries-hotplug-mem: " fmt

 #include <linux/of.h>
 #include <linux/of_address.h>
 #include <linux/memblock.h>
 #include <linux/memory.h>
 #include <linux/memory_hotplug.h>
 #include <linux/slab.h>

 #include <asm/firmware.h>
 #include <asm/machdep.h>
 #include <asm/prom.h>
 #include <asm/sparsemem.h>
 #include <asm/fadump.h>
 #include <asm/drmem.h>
 #include "pseries.h"

 static bool rtas_hp_event;

 unsigned long pseries_memory_block_size(void)
 {
 	struct device_node *np;
 	unsigned int memblock_size = MIN_MEMORY_BLOCK_SIZE;
 	struct resource r;

 	np = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
 	if (np) {
 		const __be64 *size;

 		size = of_get_property(np, "ibm,lmb-size", NULL);
 		if (size)
 			memblock_size = be64_to_cpup(size);
 		of_node_put(np);
 	} else  if (machine_is(pseries)) {
 		/* This fallback really only applies to pseries */
 		unsigned int memzero_size = 0;

 		np = of_find_node_by_path("/memory@0");
 		if (np) {
 			if (!of_address_to_resource(np, 0, &r))
 				memzero_size = resource_size(&r);
 			of_node_put(np);
 		}

 		if (memzero_size) {
 			/* We now know the size of memory@0, use this to find
 			 * the first memoryblock and get its size.
 			 */
 			char buf[64];

 			sprintf(buf, "/memory@%x", memzero_size);
 			np = of_find_node_by_path(buf);
 			if (np) {
 				if (!of_address_to_resource(np, 0, &r))
 					memblock_size = resource_size(&r);
 				of_node_put(np);
 			}
 		}
 	}
 	return memblock_size;
 }

 static void dlpar_free_property(struct property *prop)
 {
 	kfree(prop->name);
 	kfree(prop->value);
 	kfree(prop);
 }

 static struct property *dlpar_clone_property(struct property *prop,
 					     u32 prop_size)
 {
 	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_size, GFP_KERNEL);
 	if (!new_prop->name || !new_prop->value) {
 		dlpar_free_property(new_prop);
 		return NULL;
 	}

 	memcpy(new_prop->value, prop->value, prop->length);
 	new_prop->length = prop_size;

 	of_property_set_flag(new_prop, OF_DYNAMIC);
 	return new_prop;
 }

 static bool find_aa_index(struct device_node *dr_node,
 			 struct property *ala_prop,
 			 const u32 *lmb_assoc, u32 *aa_index)
 {
 	u32 *assoc_arrays, new_prop_size;
 	struct property *new_prop;
 	int aa_arrays, aa_array_entries, aa_array_sz;
 	int i, index;

 	/*
 	 * The ibm,associativity-lookup-arrays property is defined to be
 	 * a 32-bit value specifying the number of associativity arrays
 	 * followed by a 32-bitvalue specifying the number of entries per
 	 * array, followed by the associativity arrays.
 	 */
 	assoc_arrays = ala_prop->value;

 	aa_arrays = be32_to_cpu(assoc_arrays[0]);
 	aa_array_entries = be32_to_cpu(assoc_arrays[1]);
 	aa_array_sz = aa_array_entries * sizeof(u32);

 	for (i = 0; i < aa_arrays; i++) {
 		index = (i * aa_array_entries) + 2;

 		if (memcmp(&assoc_arrays[index], &lmb_assoc[1], aa_array_sz))
 			continue;

 		*aa_index = i;
 		return true;
 	}

 	new_prop_size = ala_prop->length + aa_array_sz;
 	new_prop = dlpar_clone_property(ala_prop, new_prop_size);
 	if (!new_prop)
 		return false;

 	assoc_arrays = new_prop->value;

 	/* increment the number of entries in the lookup array */
 	assoc_arrays[0] = cpu_to_be32(aa_arrays + 1);

 	/* copy the new associativity into the lookup array */
 	index = aa_arrays * aa_array_entries + 2;
 	memcpy(&assoc_arrays[index], &lmb_assoc[1], aa_array_sz);

 	of_update_property(dr_node, new_prop);

 	/*
 	 * The associativity lookup array index for this lmb is
 	 * number of entries - 1 since we added its associativity
 	 * to the end of the lookup array.
 	 */
 	*aa_index = be32_to_cpu(assoc_arrays[0]) - 1;
 	return true;
 }

 static int update_lmb_associativity_index(struct drmem_lmb *lmb)
 {
 	struct device_node *parent, *lmb_node, *dr_node;
 	struct property *ala_prop;
 	const u32 *lmb_assoc;
 	u32 aa_index;
 	bool found;

 	parent = of_find_node_by_path("/");
 	if (!parent)
 		return -ENODEV;

 	lmb_node = dlpar_configure_connector(cpu_to_be32(lmb->drc_index),
 					     parent);
 	of_node_put(parent);
 	if (!lmb_node)
 		return -EINVAL;

 	lmb_assoc = of_get_property(lmb_node, "ibm,associativity", NULL);
 	if (!lmb_assoc) {
 		dlpar_free_cc_nodes(lmb_node);
 		return -ENODEV;
 	}

 	dr_node = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
 	if (!dr_node) {
 		dlpar_free_cc_nodes(lmb_node);
 		return -ENODEV;
 	}

 	ala_prop = of_find_property(dr_node, "ibm,associativity-lookup-arrays",
 				    NULL);
 	if (!ala_prop) {
 		of_node_put(dr_node);
 		dlpar_free_cc_nodes(lmb_node);
 		return -ENODEV;
 	}

 	found = find_aa_index(dr_node, ala_prop, lmb_assoc, &aa_index);

 	of_node_put(dr_node);
 	dlpar_free_cc_nodes(lmb_node);

 	if (!found) {
 		pr_err("Could not find LMB associativity\n");
 		return -1;
 	}

 	lmb->aa_index = aa_index;
 	return 0;
 }

 static struct memory_block *lmb_to_memblock(struct drmem_lmb *lmb)
 {
 	unsigned long section_nr;
 	struct mem_section *mem_sect;
 	struct memory_block *mem_block;

 	section_nr = pfn_to_section_nr(PFN_DOWN(lmb->base_addr));
 	mem_sect = __nr_to_section(section_nr);

 	mem_block = find_memory_block(mem_sect);
 	return mem_block;
 }

 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;

 	mem_block = lmb_to_memblock(lmb);
 	if (!mem_block)
 		return -EINVAL;

 	if (online && mem_block->dev.offline)
 		rc = device_online(&mem_block->dev);
 	else if (!online && !mem_block->dev.offline)
 		rc = device_offline(&mem_block->dev);
 	else
 		rc = 0;

 	put_device(&mem_block->dev);

 	return rc;
 }

 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 drmem_lmb *lmb)
 {
 	return dlpar_change_lmb_state(lmb, false);
 }

 static int pseries_remove_memblock(unsigned long base, unsigned int memblock_size)
 {
 	unsigned long block_sz, start_pfn;
 	int sections_per_block;
 	int i, nid;

 	start_pfn = base >> PAGE_SHIFT;

 	lock_device_hotplug();

 	if (!pfn_valid(start_pfn))
 		goto out;

 	block_sz = pseries_memory_block_size();
 	sections_per_block = block_sz / MIN_MEMORY_BLOCK_SIZE;
 	nid = memory_add_physaddr_to_nid(base);

 	for (i = 0; i < sections_per_block; i++) {
 		__remove_memory(nid, base, MIN_MEMORY_BLOCK_SIZE);
 		base += MIN_MEMORY_BLOCK_SIZE;
 	}

 out:
 	/* Update memory regions for memory remove */
 	memblock_remove(base, memblock_size);
 	unlock_device_hotplug();
 	return 0;
 }

 static int pseries_remove_mem_node(struct device_node *np)
 {
 	const __be32 *regs;
 	unsigned long base;
 	unsigned int lmb_size;
 	int ret = -EINVAL;

 	/*
 	 * Check to see if we are actually removing memory
 	 */
 	if (!of_node_is_type(np, "memory"))
 		return 0;

 	/*
 	 * Find the base address and size of the memblock
 	 */
 	regs = of_get_property(np, "reg", NULL);
 	if (!regs)
 		return ret;

 	base = be64_to_cpu(*(unsigned long *)regs);
 	lmb_size = be32_to_cpu(regs[3]);

 	pseries_remove_memblock(base, lmb_size);
 	return 0;
 }

 static bool lmb_is_removable(struct drmem_lmb *lmb)
 {
 	int i, scns_per_block;
 	bool rc = true;
 	unsigned long pfn, block_sz;
 	u64 phys_addr;

 	if (!(lmb->flags & DRCONF_MEM_ASSIGNED))
 		return false;

 	block_sz = memory_block_size_bytes();
 	scns_per_block = block_sz / MIN_MEMORY_BLOCK_SIZE;
 	phys_addr = lmb->base_addr;

 #ifdef CONFIG_FA_DUMP
 	/*
 	 * Don't hot-remove memory that falls in fadump boot memory area
 	 * and memory that is reserved for capturing old kernel memory.
 	 */
 	if (is_fadump_memory_area(phys_addr, block_sz))
 		return false;
 #endif

 	for (i = 0; i < scns_per_block; i++) {
 		pfn = PFN_DOWN(phys_addr);
 		if (!pfn_present(pfn)) {
 			phys_addr += MIN_MEMORY_BLOCK_SIZE;
 			continue;
 		}

 		rc = rc && is_mem_section_removable(pfn, PAGES_PER_SECTION);
 		phys_addr += MIN_MEMORY_BLOCK_SIZE;
 	}

 	return rc;
 }

 static int dlpar_add_lmb(struct drmem_lmb *);

 static int dlpar_remove_lmb(struct drmem_lmb *lmb)
 {
 	unsigned long block_sz;
 	int rc;

 	if (!lmb_is_removable(lmb))
 		return -EINVAL;

 	rc = dlpar_offline_lmb(lmb);
 	if (rc)
 		return rc;

 	block_sz = pseries_memory_block_size();

 	__remove_memory(lmb->nid, lmb->base_addr, block_sz);

 	/* Update memory regions for memory remove */
 	memblock_remove(lmb->base_addr, block_sz);

 	invalidate_lmb_associativity_index(lmb);
 	lmb_clear_nid(lmb);
 	lmb->flags &= ~DRCONF_MEM_ASSIGNED;

 	return 0;
 }

 static int dlpar_memory_remove_by_count(u32 lmbs_to_remove)
 {
 	struct drmem_lmb *lmb;
 	int lmbs_removed = 0;
 	int lmbs_available = 0;
 	int rc;

 	pr_info("Attempting to hot-remove %d LMB(s)\n", lmbs_to_remove);

 	if (lmbs_to_remove == 0)
 		return -EINVAL;

 	/* Validate that there are enough LMBs to satisfy the request */
 	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) {
 		pr_info("Not enough LMBs available (%d of %d) to satisfy request\n",
 			lmbs_available, lmbs_to_remove);
 		return -EINVAL;
 	}

 	for_each_drmem_lmb(lmb) {
 		rc = dlpar_remove_lmb(lmb);
 		if (rc)
 			continue;

 		/* Mark this lmb so we can add it later if all of the
 		 * requested LMBs cannot be removed.
 		 */
 		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_each_drmem_lmb(lmb) {
 			if (!drmem_lmb_reserved(lmb))
 				continue;

 			rc = dlpar_add_lmb(lmb);
 			if (rc)
 				pr_err("Failed to add LMB back, drc index %x\n",
 				       lmb->drc_index);

 			drmem_remove_lmb_reservation(lmb);
 		}

 		rc = -EINVAL;
 	} else {
 		for_each_drmem_lmb(lmb) {
 			if (!drmem_lmb_reserved(lmb))
 				continue;

 			dlpar_release_drc(lmb->drc_index);
 			pr_info("Memory at %llx was hot-removed\n",
 				lmb->base_addr);

 			drmem_remove_lmb_reservation(lmb);
 		}
 		rc = 0;
 	}

 	return rc;
 }

 static int dlpar_memory_remove_by_index(u32 drc_index)
 {
 	struct drmem_lmb *lmb;
 	int lmb_found;
 	int rc;

 	pr_info("Attempting to hot-remove LMB, drc index %x\n", drc_index);

 	lmb_found = 0;
 	for_each_drmem_lmb(lmb) {
 		if (lmb->drc_index == drc_index) {
 			lmb_found = 1;
 			rc = dlpar_remove_lmb(lmb);
 			if (!rc)
 				dlpar_release_drc(lmb->drc_index);

 			break;
 		}
 	}

 	if (!lmb_found)
 		rc = -EINVAL;

 	if (rc)
 		pr_info("Failed to hot-remove memory at %llx\n",
 			lmb->base_addr);
 	else
 		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 drmem_lmb *lmb;
 	int lmb_found;
 	int rc;

 	pr_info("Attempting to update LMB, drc index %x\n", drc_index);

 	lmb_found = 0;
 	for_each_drmem_lmb(lmb) {
 		if (lmb->drc_index == drc_index) {
 			lmb_found = 1;
 			rc = dlpar_remove_lmb(lmb);
 			if (!rc) {
 				rc = dlpar_add_lmb(lmb);
 				if (rc)
 					dlpar_release_drc(lmb->drc_index);
 			}
 			break;
 		}
 	}

 	if (!lmb_found)
 		rc = -EINVAL;

 	if (rc)
 		pr_info("Failed to update memory at %llx\n",
 			lmb->base_addr);
 	else
 		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 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);

 	if (lmbs_to_remove == 0)
 		return -EINVAL;

 	rc = get_lmb_range(drc_index, lmbs_to_remove, &start_lmb, &end_lmb);
 	if (rc)
 		return -EINVAL;

 	/* Validate that there are enough LMBs to satisfy the request */
 	for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 		if (lmb->flags & DRCONF_MEM_RESERVED)
 			break;

 		lmbs_available++;
 	}

 	if (lmbs_available < lmbs_to_remove)
 		return -EINVAL;

 	for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 		if (!(lmb->flags & DRCONF_MEM_ASSIGNED))
 			continue;

 		rc = dlpar_remove_lmb(lmb);
 		if (rc)
 			break;

 		drmem_mark_lmb_reserved(lmb);
 	}

 	if (rc) {
 		pr_err("Memory indexed-count-remove failed, adding any removed LMBs\n");


 		for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 			if (!drmem_lmb_reserved(lmb))
 				continue;

 			rc = dlpar_add_lmb(lmb);
 			if (rc)
 				pr_err("Failed to add LMB, drc index %x\n",
 				       lmb->drc_index);

 			drmem_remove_lmb_reservation(lmb);
 		}
 		rc = -EINVAL;
 	} else {
 		for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 			if (!drmem_lmb_reserved(lmb))
 				continue;

 			dlpar_release_drc(lmb->drc_index);
 			pr_info("Memory at %llx (drc index %x) was hot-removed\n",
 				lmb->base_addr, lmb->drc_index);

 			drmem_remove_lmb_reservation(lmb);
 		}
 	}

 	return rc;
 }

 #else
 static inline int pseries_remove_memblock(unsigned long base,
 					  unsigned int memblock_size)
 {
 	return -EOPNOTSUPP;
 }
 static inline int pseries_remove_mem_node(struct device_node *np)
 {
 	return 0;
 }
 static inline int dlpar_memory_remove(struct pseries_hp_errorlog *hp_elog)
 {
 	return -EOPNOTSUPP;
 }
 static int dlpar_remove_lmb(struct drmem_lmb *lmb)
 {
 	return -EOPNOTSUPP;
 }
 static int dlpar_memory_remove_by_count(u32 lmbs_to_remove)
 {
 	return -EOPNOTSUPP;
 }
 static int dlpar_memory_remove_by_index(u32 drc_index)
 {
 	return -EOPNOTSUPP;
 }
 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)
 {
 	return -EOPNOTSUPP;
 }
 #endif /* CONFIG_MEMORY_HOTREMOVE */

 static int dlpar_add_lmb(struct drmem_lmb *lmb)
 {
 	unsigned long block_sz;
 	int rc;

 	if (lmb->flags & DRCONF_MEM_ASSIGNED)
 		return -EINVAL;

 	rc = update_lmb_associativity_index(lmb);
 	if (rc) {
 		dlpar_release_drc(lmb->drc_index);
 		return rc;
 	}

 	lmb_set_nid(lmb);
 	block_sz = memory_block_size_bytes();

 	/* Add the memory */
 	rc = __add_memory(lmb->nid, lmb->base_addr, block_sz);
 	if (rc) {
 		invalidate_lmb_associativity_index(lmb);
 		return rc;
 	}

 	rc = dlpar_online_lmb(lmb);
 	if (rc) {
 		__remove_memory(lmb->nid, lmb->base_addr, block_sz);
 		invalidate_lmb_associativity_index(lmb);
 		lmb_clear_nid(lmb);
 	} else {
 		lmb->flags |= DRCONF_MEM_ASSIGNED;
 	}

 	return rc;
 }

 static int dlpar_memory_add_by_count(u32 lmbs_to_add)
 {
 	struct drmem_lmb *lmb;
 	int lmbs_available = 0;
 	int lmbs_added = 0;
 	int rc;

 	pr_info("Attempting to hot-add %d LMB(s)\n", lmbs_to_add);

 	if (lmbs_to_add == 0)
 		return -EINVAL;

 	/* Validate that there are enough LMBs to satisfy the request */
 	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_each_drmem_lmb(lmb) {
 		if (lmb->flags & DRCONF_MEM_ASSIGNED)
 			continue;

 		rc = dlpar_acquire_drc(lmb->drc_index);
 		if (rc)
 			continue;

 		rc = dlpar_add_lmb(lmb);
 		if (rc) {
 			dlpar_release_drc(lmb->drc_index);
 			continue;
 		}

 		/* Mark this lmb so we can remove it later if all of the
 		 * requested LMBs cannot be added.
 		 */
 		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_each_drmem_lmb(lmb) {
 			if (!drmem_lmb_reserved(lmb))
 				continue;

 			rc = dlpar_remove_lmb(lmb);
 			if (rc)
 				pr_err("Failed to remove LMB, drc index %x\n",
 				       lmb->drc_index);
 			else
 				dlpar_release_drc(lmb->drc_index);

 			drmem_remove_lmb_reservation(lmb);
 		}
 		rc = -EINVAL;
 	} else {
 		for_each_drmem_lmb(lmb) {
 			if (!drmem_lmb_reserved(lmb))
 				continue;

 			pr_info("Memory at %llx (drc index %x) was hot-added\n",
 				lmb->base_addr, lmb->drc_index);
 			drmem_remove_lmb_reservation(lmb);
 		}
 		rc = 0;
 	}

 	return rc;
 }

 static int dlpar_memory_add_by_index(u32 drc_index)
 {
 	struct drmem_lmb *lmb;
 	int rc, lmb_found;

 	pr_info("Attempting to hot-add LMB, drc index %x\n", drc_index);

 	lmb_found = 0;
 	for_each_drmem_lmb(lmb) {
 		if (lmb->drc_index == drc_index) {
 			lmb_found = 1;
 			rc = dlpar_acquire_drc(lmb->drc_index);
 			if (!rc) {
 				rc = dlpar_add_lmb(lmb);
 				if (rc)
 					dlpar_release_drc(lmb->drc_index);
 			}

 			break;
 		}
 	}

 	if (!lmb_found)
 		rc = -EINVAL;

 	if (rc)
 		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",
 			lmb->base_addr, drc_index);

 	return rc;
 }

 static int dlpar_memory_add_by_ic(u32 lmbs_to_add, u32 drc_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);

 	if (lmbs_to_add == 0)
 		return -EINVAL;

 	rc = get_lmb_range(drc_index, lmbs_to_add, &start_lmb, &end_lmb);
 	if (rc)
 		return -EINVAL;

 	/* Validate that the LMBs in this range are not reserved */
 	for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 		if (lmb->flags & DRCONF_MEM_RESERVED)
 			break;

 		lmbs_available++;
 	}

 	if (lmbs_available < lmbs_to_add)
 		return -EINVAL;

 	for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 		if (lmb->flags & DRCONF_MEM_ASSIGNED)
 			continue;

 		rc = dlpar_acquire_drc(lmb->drc_index);
 		if (rc)
 			break;

 		rc = dlpar_add_lmb(lmb);
 		if (rc) {
 			dlpar_release_drc(lmb->drc_index);
 			break;
 		}

 		drmem_mark_lmb_reserved(lmb);
 	}

 	if (rc) {
 		pr_err("Memory indexed-count-add failed, removing any added LMBs\n");

 		for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 			if (!drmem_lmb_reserved(lmb))
 				continue;

 			rc = dlpar_remove_lmb(lmb);
 			if (rc)
 				pr_err("Failed to remove LMB, drc index %x\n",
 				       lmb->drc_index);
 			else
 				dlpar_release_drc(lmb->drc_index);

 			drmem_remove_lmb_reservation(lmb);
 		}
 		rc = -EINVAL;
 	} else {
 		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",
 				lmb->base_addr, lmb->drc_index);
 			drmem_remove_lmb_reservation(lmb);
 		}
 	}

 	return rc;
 }

 int dlpar_memory(struct pseries_hp_errorlog *hp_elog)
 {
 	u32 count, drc_index;
 	int rc;

 	lock_device_hotplug();

 	switch (hp_elog->action) {
 	case PSERIES_HP_ELOG_ACTION_ADD:
 		switch (hp_elog->id_type) {
 		case PSERIES_HP_ELOG_ID_DRC_COUNT:
 			count = hp_elog->_drc_u.drc_count;
 			rc = dlpar_memory_add_by_count(count);
 			break;
 		case PSERIES_HP_ELOG_ID_DRC_INDEX:
 			drc_index = hp_elog->_drc_u.drc_index;
 			rc = dlpar_memory_add_by_index(drc_index);
 			break;
 		case 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);
 			break;
 		default:
 			rc = -EINVAL;
 			break;
 		}

 		break;
 	case PSERIES_HP_ELOG_ACTION_REMOVE:
 		switch (hp_elog->id_type) {
 		case PSERIES_HP_ELOG_ID_DRC_COUNT:
 			count = hp_elog->_drc_u.drc_count;
 			rc = dlpar_memory_remove_by_count(count);
 			break;
 		case PSERIES_HP_ELOG_ID_DRC_INDEX:
 			drc_index = hp_elog->_drc_u.drc_index;
 			rc = dlpar_memory_remove_by_index(drc_index);
 			break;
 		case 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);
 			break;
 		default:
 			rc = -EINVAL;
 			break;
 		}

 		break;
 	case PSERIES_HP_ELOG_ACTION_READD:
 		drc_index = hp_elog->_drc_u.drc_index;
 		rc = dlpar_memory_readd_by_index(drc_index);
 		break;
 	default:
 		pr_err("Invalid action (%d) specified\n", hp_elog->action);
 		rc = -EINVAL;
 		break;
 	}

 	if (!rc) {
 		rtas_hp_event = true;
 		rc = drmem_update_dt();
 		rtas_hp_event = false;
 	}

 	unlock_device_hotplug();
 	return rc;
 }

 static int pseries_add_mem_node(struct device_node *np)
 {
 	const __be32 *regs;
 	unsigned long base;
 	unsigned int lmb_size;
 	int ret = -EINVAL;

 	/*
 	 * Check to see if we are actually adding memory
 	 */
 	if (!of_node_is_type(np, "memory"))
 		return 0;

 	/*
 	 * Find the base and size of the memblock
 	 */
 	regs = of_get_property(np, "reg", NULL);
 	if (!regs)
 		return ret;

 	base = be64_to_cpu(*(unsigned long *)regs);
 	lmb_size = be32_to_cpu(regs[3]);

 	/*
 	 * Update memory region to represent the memory add
 	 */
 	ret = memblock_add(base, lmb_size);
 	return (ret < 0) ? -EINVAL : 0;
 }

 static int pseries_update_drconf_memory(struct of_reconfig_data *pr)
 {
 	struct of_drconf_cell_v1 *new_drmem, *old_drmem;
 	unsigned long memblock_size;
 	u32 entries;
 	__be32 *p;
 	int i, rc = -EINVAL;

 	if (rtas_hp_event)
 		return 0;

 	memblock_size = pseries_memory_block_size();
 	if (!memblock_size)
 		return -EINVAL;

 	if (!pr->old_prop)
 		return 0;

 	p = (__be32 *) pr->old_prop->value;
 	if (!p)
 		return -EINVAL;

 	/* The first int of the property is the number of lmb's described
 	 * by the property. This is followed by an array of of_drconf_cell
 	 * entries. Get the number of entries and skip to the array of
 	 * of_drconf_cell's.
 	 */
 	entries = be32_to_cpu(*p++);
 	old_drmem = (struct of_drconf_cell_v1 *)p;

 	p = (__be32 *)pr->prop->value;
 	p++;
 	new_drmem = (struct of_drconf_cell_v1 *)p;

 	for (i = 0; i < entries; i++) {
 		if ((be32_to_cpu(old_drmem[i].flags) & DRCONF_MEM_ASSIGNED) &&
 		    (!(be32_to_cpu(new_drmem[i].flags) & DRCONF_MEM_ASSIGNED))) {
 			rc = pseries_remove_memblock(
 				be64_to_cpu(old_drmem[i].base_addr),
 						     memblock_size);
 			break;
 		} else if ((!(be32_to_cpu(old_drmem[i].flags) &
 			    DRCONF_MEM_ASSIGNED)) &&
 			    (be32_to_cpu(new_drmem[i].flags) &
 			    DRCONF_MEM_ASSIGNED)) {
 			rc = memblock_add(be64_to_cpu(old_drmem[i].base_addr),
 					  memblock_size);
 			rc = (rc < 0) ? -EINVAL : 0;
 			break;
 		}
 	}
 	return rc;
 }

 static int pseries_memory_notifier(struct notifier_block *nb,
 				   unsigned long action, void *data)
 {
 	struct of_reconfig_data *rd = data;
 	int err = 0;

 	switch (action) {
 	case OF_RECONFIG_ATTACH_NODE:
 		err = pseries_add_mem_node(rd->dn);
 		break;
 	case OF_RECONFIG_DETACH_NODE:
 		err = pseries_remove_mem_node(rd->dn);
 		break;
 	case OF_RECONFIG_UPDATE_PROPERTY:
 		if (!strcmp(rd->prop->name, "ibm,dynamic-memory"))
 			err = pseries_update_drconf_memory(rd);
 		break;
 	}
 	return notifier_from_errno(err);
 }

 static struct notifier_block pseries_mem_nb = {
 	.notifier_call = pseries_memory_notifier,
 };

 static int __init pseries_memory_hotplug_init(void)
 {
 	if (firmware_has_feature(FW_FEATURE_LPAR))
 		of_reconfig_notifier_register(&pseries_mem_nb);

 	return 0;
 }
 machine_device_initcall(pseries, pseries_memory_hotplug_init);