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linux_old1/arch/powerpc/platforms/ps3/mm.c

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/*
* PS3 address space management.
*
* Copyright (C) 2006 Sony Computer Entertainment Inc.
* Copyright 2006 Sony Corp.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/memory_hotplug.h>
#include <asm/firmware.h>
#include <asm/lmb.h>
#include <asm/udbg.h>
#include <asm/lv1call.h>
#include "platform.h"
#if defined(DEBUG)
#define DBG(fmt...) udbg_printf(fmt)
#else
#define DBG(fmt...) do{if(0)printk(fmt);}while(0)
#endif
enum {
#if defined(CONFIG_PS3_USE_LPAR_ADDR)
USE_LPAR_ADDR = 1,
#else
USE_LPAR_ADDR = 0,
#endif
#if defined(CONFIG_PS3_DYNAMIC_DMA)
USE_DYNAMIC_DMA = 1,
#else
USE_DYNAMIC_DMA = 0,
#endif
};
enum {
PAGE_SHIFT_4K = 12U,
PAGE_SHIFT_64K = 16U,
PAGE_SHIFT_16M = 24U,
};
static unsigned long make_page_sizes(unsigned long a, unsigned long b)
{
return (a << 56) | (b << 48);
}
enum {
ALLOCATE_MEMORY_TRY_ALT_UNIT = 0X04,
ALLOCATE_MEMORY_ADDR_ZERO = 0X08,
};
/* valid htab sizes are {18,19,20} = 256K, 512K, 1M */
enum {
HTAB_SIZE_MAX = 20U, /* HV limit of 1MB */
HTAB_SIZE_MIN = 18U, /* CPU limit of 256KB */
};
/*============================================================================*/
/* virtual address space routines */
/*============================================================================*/
/**
* struct mem_region - memory region structure
* @base: base address
* @size: size in bytes
* @offset: difference between base and rm.size
*/
struct mem_region {
unsigned long base;
unsigned long size;
unsigned long offset;
};
/**
* struct map - address space state variables holder
* @total: total memory available as reported by HV
* @vas_id - HV virtual address space id
* @htab_size: htab size in bytes
*
* The HV virtual address space (vas) allows for hotplug memory regions.
* Memory regions can be created and destroyed in the vas at runtime.
* @rm: real mode (bootmem) region
* @r1: hotplug memory region(s)
*
* ps3 addresses
* virt_addr: a cpu 'translated' effective address
* phys_addr: an address in what Linux thinks is the physical address space
* lpar_addr: an address in the HV virtual address space
* bus_addr: an io controller 'translated' address on a device bus
*/
struct map {
unsigned long total;
unsigned long vas_id;
unsigned long htab_size;
struct mem_region rm;
struct mem_region r1;
};
#define debug_dump_map(x) _debug_dump_map(x, __func__, __LINE__)
static void _debug_dump_map(const struct map* m, const char* func, int line)
{
DBG("%s:%d: map.total = %lxh\n", func, line, m->total);
DBG("%s:%d: map.rm.size = %lxh\n", func, line, m->rm.size);
DBG("%s:%d: map.vas_id = %lu\n", func, line, m->vas_id);
DBG("%s:%d: map.htab_size = %lxh\n", func, line, m->htab_size);
DBG("%s:%d: map.r1.base = %lxh\n", func, line, m->r1.base);
DBG("%s:%d: map.r1.offset = %lxh\n", func, line, m->r1.offset);
DBG("%s:%d: map.r1.size = %lxh\n", func, line, m->r1.size);
}
static struct map map;
/**
* ps3_mm_phys_to_lpar - translate a linux physical address to lpar address
* @phys_addr: linux physical address
*/
unsigned long ps3_mm_phys_to_lpar(unsigned long phys_addr)
{
BUG_ON(is_kernel_addr(phys_addr));
if (USE_LPAR_ADDR)
return phys_addr;
else
return (phys_addr < map.rm.size || phys_addr >= map.total)
? phys_addr : phys_addr + map.r1.offset;
}
EXPORT_SYMBOL(ps3_mm_phys_to_lpar);
/**
* ps3_mm_vas_create - create the virtual address space
*/
void __init ps3_mm_vas_create(unsigned long* htab_size)
{
int result;
unsigned long start_address;
unsigned long size;
unsigned long access_right;
unsigned long max_page_size;
unsigned long flags;
result = lv1_query_logical_partition_address_region_info(0,
&start_address, &size, &access_right, &max_page_size,
&flags);
if (result) {
DBG("%s:%d: lv1_query_logical_partition_address_region_info "
"failed: %s\n", __func__, __LINE__,
ps3_result(result));
goto fail;
}
if (max_page_size < PAGE_SHIFT_16M) {
DBG("%s:%d: bad max_page_size %lxh\n", __func__, __LINE__,
max_page_size);
goto fail;
}
BUILD_BUG_ON(CONFIG_PS3_HTAB_SIZE > HTAB_SIZE_MAX);
BUILD_BUG_ON(CONFIG_PS3_HTAB_SIZE < HTAB_SIZE_MIN);
result = lv1_construct_virtual_address_space(CONFIG_PS3_HTAB_SIZE,
2, make_page_sizes(PAGE_SHIFT_16M, PAGE_SHIFT_64K),
&map.vas_id, &map.htab_size);
if (result) {
DBG("%s:%d: lv1_construct_virtual_address_space failed: %s\n",
__func__, __LINE__, ps3_result(result));
goto fail;
}
result = lv1_select_virtual_address_space(map.vas_id);
if (result) {
DBG("%s:%d: lv1_select_virtual_address_space failed: %s\n",
__func__, __LINE__, ps3_result(result));
goto fail;
}
*htab_size = map.htab_size;
debug_dump_map(&map);
return;
fail:
panic("ps3_mm_vas_create failed");
}
/**
* ps3_mm_vas_destroy -
*/
void ps3_mm_vas_destroy(void)
{
if (map.vas_id) {
lv1_select_virtual_address_space(0);
lv1_destruct_virtual_address_space(map.vas_id);
map.vas_id = 0;
}
}
/*============================================================================*/
/* memory hotplug routines */
/*============================================================================*/
/**
* ps3_mm_region_create - create a memory region in the vas
* @r: pointer to a struct mem_region to accept initialized values
* @size: requested region size
*
* This implementation creates the region with the vas large page size.
* @size is rounded down to a multiple of the vas large page size.
*/
int ps3_mm_region_create(struct mem_region *r, unsigned long size)
{
int result;
unsigned long muid;
r->size = _ALIGN_DOWN(size, 1 << PAGE_SHIFT_16M);
DBG("%s:%d requested %lxh\n", __func__, __LINE__, size);
DBG("%s:%d actual %lxh\n", __func__, __LINE__, r->size);
DBG("%s:%d difference %lxh (%luMB)\n", __func__, __LINE__,
(unsigned long)(size - r->size),
(size - r->size) / 1024 / 1024);
if (r->size == 0) {
DBG("%s:%d: size == 0\n", __func__, __LINE__);
result = -1;
goto zero_region;
}
result = lv1_allocate_memory(r->size, PAGE_SHIFT_16M, 0,
ALLOCATE_MEMORY_TRY_ALT_UNIT, &r->base, &muid);
if (result || r->base < map.rm.size) {
DBG("%s:%d: lv1_allocate_memory failed: %s\n",
__func__, __LINE__, ps3_result(result));
goto zero_region;
}
r->offset = r->base - map.rm.size;
return result;
zero_region:
r->size = r->base = r->offset = 0;
return result;
}
/**
* ps3_mm_region_destroy - destroy a memory region
* @r: pointer to struct mem_region
*/
void ps3_mm_region_destroy(struct mem_region *r)
{
if (r->base) {
lv1_release_memory(r->base);
r->size = r->base = r->offset = 0;
map.total = map.rm.size;
}
}
/**
* ps3_mm_add_memory - hot add memory
*/
static int __init ps3_mm_add_memory(void)
{
int result;
unsigned long start_addr;
unsigned long start_pfn;
unsigned long nr_pages;
if (!firmware_has_feature(FW_FEATURE_PS3_LV1))
return 0;
BUG_ON(!mem_init_done);
start_addr = USE_LPAR_ADDR ? map.r1.base : map.rm.size;
start_pfn = start_addr >> PAGE_SHIFT;
nr_pages = (map.r1.size + PAGE_SIZE - 1) >> PAGE_SHIFT;
DBG("%s:%d: start_addr %lxh, start_pfn %lxh, nr_pages %lxh\n",
__func__, __LINE__, start_addr, start_pfn, nr_pages);
result = add_memory(0, start_addr, map.r1.size);
if (result) {
DBG("%s:%d: add_memory failed: (%d)\n",
__func__, __LINE__, result);
return result;
}
result = online_pages(start_pfn, nr_pages);
if (result)
DBG("%s:%d: online_pages failed: (%d)\n",
__func__, __LINE__, result);
return result;
}
core_initcall(ps3_mm_add_memory);
/*============================================================================*/
/* dma routines */
/*============================================================================*/
/**
* dma_lpar_to_bus - Translate an lpar address to ioc mapped bus address.
* @r: pointer to dma region structure
* @lpar_addr: HV lpar address
*/
static unsigned long dma_lpar_to_bus(struct ps3_dma_region *r,
unsigned long lpar_addr)
{
BUG_ON(lpar_addr >= map.r1.base + map.r1.size);
return r->bus_addr + (lpar_addr <= map.rm.size ? lpar_addr
: lpar_addr - map.r1.offset);
}
#define dma_dump_region(_a) _dma_dump_region(_a, __func__, __LINE__)
static void _dma_dump_region(const struct ps3_dma_region *r, const char* func,
int line)
{
DBG("%s:%d: dev %u:%u\n", func, line, r->did.bus_id,
r->did.dev_id);
DBG("%s:%d: page_size %u\n", func, line, r->page_size);
DBG("%s:%d: bus_addr %lxh\n", func, line, r->bus_addr);
DBG("%s:%d: len %lxh\n", func, line, r->len);
}
/**
* dma_chunk - A chunk of dma pages mapped by the io controller.
* @region - The dma region that owns this chunk.
* @lpar_addr: Starting lpar address of the area to map.
* @bus_addr: Starting ioc bus address of the area to map.
* @len: Length in bytes of the area to map.
* @link: A struct list_head used with struct ps3_dma_region.chunk_list, the
* list of all chuncks owned by the region.
*
* This implementation uses a very simple dma page manager
* based on the dma_chunk structure. This scheme assumes
* that all drivers use very well behaved dma ops.
*/
struct dma_chunk {
struct ps3_dma_region *region;
unsigned long lpar_addr;
unsigned long bus_addr;
unsigned long len;
struct list_head link;
unsigned int usage_count;
};
#define dma_dump_chunk(_a) _dma_dump_chunk(_a, __func__, __LINE__)
static void _dma_dump_chunk (const struct dma_chunk* c, const char* func,
int line)
{
DBG("%s:%d: r.dev %u:%u\n", func, line,
c->region->did.bus_id, c->region->did.dev_id);
DBG("%s:%d: r.bus_addr %lxh\n", func, line, c->region->bus_addr);
DBG("%s:%d: r.page_size %u\n", func, line, c->region->page_size);
DBG("%s:%d: r.len %lxh\n", func, line, c->region->len);
DBG("%s:%d: c.lpar_addr %lxh\n", func, line, c->lpar_addr);
DBG("%s:%d: c.bus_addr %lxh\n", func, line, c->bus_addr);
DBG("%s:%d: c.len %lxh\n", func, line, c->len);
}
static struct dma_chunk * dma_find_chunk(struct ps3_dma_region *r,
unsigned long bus_addr, unsigned long len)
{
struct dma_chunk *c;
unsigned long aligned_bus = _ALIGN_DOWN(bus_addr, 1 << r->page_size);
unsigned long aligned_len = _ALIGN_UP(len, 1 << r->page_size);
list_for_each_entry(c, &r->chunk_list.head, link) {
/* intersection */
if (aligned_bus >= c->bus_addr
&& aligned_bus < c->bus_addr + c->len
&& aligned_bus + aligned_len <= c->bus_addr + c->len) {
return c;
}
/* below */
if (aligned_bus + aligned_len <= c->bus_addr) {
continue;
}
/* above */
if (aligned_bus >= c->bus_addr + c->len) {
continue;
}
/* we don't handle the multi-chunk case for now */
dma_dump_chunk(c);
BUG();
}
return NULL;
}
static int dma_free_chunk(struct dma_chunk *c)
{
int result = 0;
if (c->bus_addr) {
result = lv1_unmap_device_dma_region(c->region->did.bus_id,
c->region->did.dev_id, c->bus_addr, c->len);
BUG_ON(result);
}
kfree(c);
return result;
}
/**
* dma_map_pages - Maps dma pages into the io controller bus address space.
* @r: Pointer to a struct ps3_dma_region.
* @phys_addr: Starting physical address of the area to map.
* @len: Length in bytes of the area to map.
* c_out: A pointer to receive an allocated struct dma_chunk for this area.
*
* This is the lowest level dma mapping routine, and is the one that will
* make the HV call to add the pages into the io controller address space.
*/
static int dma_map_pages(struct ps3_dma_region *r, unsigned long phys_addr,
unsigned long len, struct dma_chunk **c_out)
{
int result;
struct dma_chunk *c;
c = kzalloc(sizeof(struct dma_chunk), GFP_ATOMIC);
if (!c) {
result = -ENOMEM;
goto fail_alloc;
}
c->region = r;
c->lpar_addr = ps3_mm_phys_to_lpar(phys_addr);
c->bus_addr = dma_lpar_to_bus(r, c->lpar_addr);
c->len = len;
result = lv1_map_device_dma_region(c->region->did.bus_id,
c->region->did.dev_id, c->lpar_addr, c->bus_addr, c->len,
0xf800000000000000UL);
if (result) {
DBG("%s:%d: lv1_map_device_dma_region failed: %s\n",
__func__, __LINE__, ps3_result(result));
goto fail_map;
}
list_add(&c->link, &r->chunk_list.head);
*c_out = c;
return 0;
fail_map:
kfree(c);
fail_alloc:
*c_out = NULL;
DBG(" <- %s:%d\n", __func__, __LINE__);
return result;
}
/**
* dma_region_create - Create a device dma region.
* @r: Pointer to a struct ps3_dma_region.
*
* This is the lowest level dma region create routine, and is the one that
* will make the HV call to create the region.
*/
static int dma_region_create(struct ps3_dma_region* r)
{
int result;
r->len = _ALIGN_UP(map.total, 1 << r->page_size);
INIT_LIST_HEAD(&r->chunk_list.head);
spin_lock_init(&r->chunk_list.lock);
result = lv1_allocate_device_dma_region(r->did.bus_id, r->did.dev_id,
r->len, r->page_size, r->region_type, &r->bus_addr);
dma_dump_region(r);
if (result) {
DBG("%s:%d: lv1_allocate_device_dma_region failed: %s\n",
__func__, __LINE__, ps3_result(result));
r->len = r->bus_addr = 0;
}
return result;
}
/**
* dma_region_free - Free a device dma region.
* @r: Pointer to a struct ps3_dma_region.
*
* This is the lowest level dma region free routine, and is the one that
* will make the HV call to free the region.
*/
static int dma_region_free(struct ps3_dma_region* r)
{
int result;
struct dma_chunk *c;
struct dma_chunk *tmp;
list_for_each_entry_safe(c, tmp, &r->chunk_list.head, link) {
list_del(&c->link);
dma_free_chunk(c);
}
result = lv1_free_device_dma_region(r->did.bus_id, r->did.dev_id,
r->bus_addr);
if (result)
DBG("%s:%d: lv1_free_device_dma_region failed: %s\n",
__func__, __LINE__, ps3_result(result));
r->len = r->bus_addr = 0;
return result;
}
/**
* dma_map_area - Map an area of memory into a device dma region.
* @r: Pointer to a struct ps3_dma_region.
* @virt_addr: Starting virtual address of the area to map.
* @len: Length in bytes of the area to map.
* @bus_addr: A pointer to return the starting ioc bus address of the area to
* map.
*
* This is the common dma mapping routine.
*/
static int dma_map_area(struct ps3_dma_region *r, unsigned long virt_addr,
unsigned long len, unsigned long *bus_addr)
{
int result;
unsigned long flags;
struct dma_chunk *c;
unsigned long phys_addr = is_kernel_addr(virt_addr) ? __pa(virt_addr)
: virt_addr;
*bus_addr = dma_lpar_to_bus(r, ps3_mm_phys_to_lpar(phys_addr));
if (!USE_DYNAMIC_DMA) {
unsigned long lpar_addr = ps3_mm_phys_to_lpar(phys_addr);
DBG(" -> %s:%d\n", __func__, __LINE__);
DBG("%s:%d virt_addr %lxh\n", __func__, __LINE__,
virt_addr);
DBG("%s:%d phys_addr %lxh\n", __func__, __LINE__,
phys_addr);
DBG("%s:%d lpar_addr %lxh\n", __func__, __LINE__,
lpar_addr);
DBG("%s:%d len %lxh\n", __func__, __LINE__, len);
DBG("%s:%d bus_addr %lxh (%lxh)\n", __func__, __LINE__,
*bus_addr, len);
}
spin_lock_irqsave(&r->chunk_list.lock, flags);
c = dma_find_chunk(r, *bus_addr, len);
if (c) {
c->usage_count++;
spin_unlock_irqrestore(&r->chunk_list.lock, flags);
return 0;
}
result = dma_map_pages(r, _ALIGN_DOWN(phys_addr, 1 << r->page_size),
_ALIGN_UP(len, 1 << r->page_size), &c);
if (result) {
*bus_addr = 0;
DBG("%s:%d: dma_map_pages failed (%d)\n",
__func__, __LINE__, result);
spin_unlock_irqrestore(&r->chunk_list.lock, flags);
return result;
}
c->usage_count = 1;
spin_unlock_irqrestore(&r->chunk_list.lock, flags);
return result;
}
/**
* dma_unmap_area - Unmap an area of memory from a device dma region.
* @r: Pointer to a struct ps3_dma_region.
* @bus_addr: The starting ioc bus address of the area to unmap.
* @len: Length in bytes of the area to unmap.
*
* This is the common dma unmap routine.
*/
int dma_unmap_area(struct ps3_dma_region *r, unsigned long bus_addr,
unsigned long len)
{
unsigned long flags;
struct dma_chunk *c;
spin_lock_irqsave(&r->chunk_list.lock, flags);
c = dma_find_chunk(r, bus_addr, len);
if (!c) {
unsigned long aligned_bus = _ALIGN_DOWN(bus_addr,
1 << r->page_size);
unsigned long aligned_len = _ALIGN_UP(len, 1 << r->page_size);
DBG("%s:%d: not found: bus_addr %lxh\n",
__func__, __LINE__, bus_addr);
DBG("%s:%d: not found: len %lxh\n",
__func__, __LINE__, len);
DBG("%s:%d: not found: aligned_bus %lxh\n",
__func__, __LINE__, aligned_bus);
DBG("%s:%d: not found: aligned_len %lxh\n",
__func__, __LINE__, aligned_len);
BUG();
}
c->usage_count--;
if (!c->usage_count) {
list_del(&c->link);
dma_free_chunk(c);
}
spin_unlock_irqrestore(&r->chunk_list.lock, flags);
return 0;
}
/**
* dma_region_create_linear - Setup a linear dma maping for a device.
* @r: Pointer to a struct ps3_dma_region.
*
* This routine creates an HV dma region for the device and maps all available
* ram into the io controller bus address space.
*/
static int dma_region_create_linear(struct ps3_dma_region *r)
{
int result;
unsigned long tmp;
/* force 16M dma pages for linear mapping */
if (r->page_size != PS3_DMA_16M) {
pr_info("%s:%d: forcing 16M pages for linear map\n",
__func__, __LINE__);
r->page_size = PS3_DMA_16M;
}
result = dma_region_create(r);
BUG_ON(result);
result = dma_map_area(r, map.rm.base, map.rm.size, &tmp);
BUG_ON(result);
if (USE_LPAR_ADDR)
result = dma_map_area(r, map.r1.base, map.r1.size,
&tmp);
else
result = dma_map_area(r, map.rm.size, map.r1.size,
&tmp);
BUG_ON(result);
return result;
}
/**
* dma_region_free_linear - Free a linear dma mapping for a device.
* @r: Pointer to a struct ps3_dma_region.
*
* This routine will unmap all mapped areas and free the HV dma region.
*/
static int dma_region_free_linear(struct ps3_dma_region *r)
{
int result;
result = dma_unmap_area(r, dma_lpar_to_bus(r, 0), map.rm.size);
BUG_ON(result);
result = dma_unmap_area(r, dma_lpar_to_bus(r, map.r1.base),
map.r1.size);
BUG_ON(result);
result = dma_region_free(r);
BUG_ON(result);
return result;
}
/**
* dma_map_area_linear - Map an area of memory into a device dma region.
* @r: Pointer to a struct ps3_dma_region.
* @virt_addr: Starting virtual address of the area to map.
* @len: Length in bytes of the area to map.
* @bus_addr: A pointer to return the starting ioc bus address of the area to
* map.
*
* This routine just returns the coresponding bus address. Actual mapping
* occurs in dma_region_create_linear().
*/
static int dma_map_area_linear(struct ps3_dma_region *r,
unsigned long virt_addr, unsigned long len, unsigned long *bus_addr)
{
unsigned long phys_addr = is_kernel_addr(virt_addr) ? __pa(virt_addr)
: virt_addr;
*bus_addr = dma_lpar_to_bus(r, ps3_mm_phys_to_lpar(phys_addr));
return 0;
}
/**
* dma_unmap_area_linear - Unmap an area of memory from a device dma region.
* @r: Pointer to a struct ps3_dma_region.
* @bus_addr: The starting ioc bus address of the area to unmap.
* @len: Length in bytes of the area to unmap.
*
* This routine does nothing. Unmapping occurs in dma_region_free_linear().
*/
static int dma_unmap_area_linear(struct ps3_dma_region *r,
unsigned long bus_addr, unsigned long len)
{
return 0;
}
int ps3_dma_region_create(struct ps3_dma_region *r)
{
return (USE_DYNAMIC_DMA)
? dma_region_create(r)
: dma_region_create_linear(r);
}
int ps3_dma_region_free(struct ps3_dma_region *r)
{
return (USE_DYNAMIC_DMA)
? dma_region_free(r)
: dma_region_free_linear(r);
}
int ps3_dma_map(struct ps3_dma_region *r, unsigned long virt_addr,
unsigned long len, unsigned long *bus_addr)
{
return (USE_DYNAMIC_DMA)
? dma_map_area(r, virt_addr, len, bus_addr)
: dma_map_area_linear(r, virt_addr, len, bus_addr);
}
int ps3_dma_unmap(struct ps3_dma_region *r, unsigned long bus_addr,
unsigned long len)
{
return (USE_DYNAMIC_DMA) ? dma_unmap_area(r, bus_addr, len)
: dma_unmap_area_linear(r, bus_addr, len);
}
/*============================================================================*/
/* system startup routines */
/*============================================================================*/
/**
* ps3_mm_init - initialize the address space state variables
*/
void __init ps3_mm_init(void)
{
int result;
DBG(" -> %s:%d\n", __func__, __LINE__);
result = ps3_repository_read_mm_info(&map.rm.base, &map.rm.size,
&map.total);
if (result)
panic("ps3_repository_read_mm_info() failed");
map.rm.offset = map.rm.base;
map.vas_id = map.htab_size = 0;
/* this implementation assumes map.rm.base is zero */
BUG_ON(map.rm.base);
BUG_ON(!map.rm.size);
lmb_add(map.rm.base, map.rm.size);
lmb_analyze();
/* arrange to do this in ps3_mm_add_memory */
ps3_mm_region_create(&map.r1, map.total - map.rm.size);
DBG(" <- %s:%d\n", __func__, __LINE__);
}
/**
* ps3_mm_shutdown - final cleanup of address space
*/
void ps3_mm_shutdown(void)
{
ps3_mm_region_destroy(&map.r1);
map.total = map.rm.size;
}
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