Commit a5645a61 authored by Yinghai Lu's avatar Yinghai Lu Committed by Ingo Molnar
Browse files

mm: allow reserve_bootmem() cross nodes 



split reserve_bootmem_core() into two functions, one which checks
conflicts, and one which sets the bits.

and make reserve_bootmem to loop bdata_list to cross the nodes.

user could be crashkernel and ramdisk..., in case the range provided
by those externalities crosses the nodes.

Signed-off-by: default avatarYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 9a2dc04c

mm/bootmem.c

+69 −23
Original line number Diff line number Diff line
@@ -111,44 +111,74 @@ static unsigned long __init init_bootmem_core(pg_data_t *pgdat, 
 * might be used for boot-time allocations - or it might get added

 * to the free page pool later on.

 */

static int __init reserve_bootmem_core(bootmem_data_t *bdata,

static int __init can_reserve_bootmem_core(bootmem_data_t *bdata,

			unsigned long addr, unsigned long size, int flags)

{

	unsigned long sidx, eidx;

	unsigned long i;

	int ret;



	BUG_ON(!size);



	/* out of range, don't hold other */

	if (addr + size < bdata->node_boot_start ||

		PFN_DOWN(addr) > bdata->node_low_pfn)

		return 0;



	/*

	 * round up, partially reserved pages are considered

	 * fully reserved.

	 * Round up to index to the range.

	 */

	if (addr > bdata->node_boot_start)

		sidx= PFN_DOWN(addr - bdata->node_boot_start);

	else

		sidx = 0;



	eidx = PFN_UP(addr + size - bdata->node_boot_start);

	if (eidx > bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start))

		eidx = bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start);



	for (i = sidx; i < eidx; i++) {

		if (test_bit(i, bdata->node_bootmem_map)) {

			if (flags & BOOTMEM_EXCLUSIVE)

				return -EBUSY;

		}

	}



	return 0;



}



static void __init reserve_bootmem_core(bootmem_data_t *bdata,

			unsigned long addr, unsigned long size, int flags)

{

	unsigned long sidx, eidx;

	unsigned long i;



	BUG_ON(!size);

	BUG_ON(PFN_DOWN(addr) >= bdata->node_low_pfn);

	BUG_ON(PFN_UP(addr + size) > bdata->node_low_pfn);

	BUG_ON(addr < bdata->node_boot_start);



	/* out of range */

	if (addr + size < bdata->node_boot_start ||

		PFN_DOWN(addr) > bdata->node_low_pfn)

		return;



	/*

	 * Round up to index to the range.

	 */

	if (addr > bdata->node_boot_start)

		sidx= PFN_DOWN(addr - bdata->node_boot_start);

	else

		sidx = 0;



	eidx = PFN_UP(addr + size - bdata->node_boot_start);

	if (eidx > bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start))

		eidx = bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start);



	for (i = sidx; i < eidx; i++)

	for (i = sidx; i < eidx; i++) {

		if (test_and_set_bit(i, bdata->node_bootmem_map)) {

#ifdef CONFIG_DEBUG_BOOTMEM

			printk("hm, page %08lx reserved twice.\n", i*PAGE_SIZE);

#endif

			if (flags & BOOTMEM_EXCLUSIVE) {

				ret = -EBUSY;

				goto err;

		}

	}



	return 0;



err:

	/* unreserve memory we accidentally reserved */

	for (i--; i >= sidx; i--)

		clear_bit(i, bdata->node_bootmem_map);



	return ret;

}



static void __init free_bootmem_core(bootmem_data_t *bdata, unsigned long addr,
@@ -415,6 +445,11 @@ unsigned long __init init_bootmem_node(pg_data_t *pgdat, unsigned long freepfn, 
void __init reserve_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,

				 unsigned long size, int flags)

{

	int ret;



	ret = can_reserve_bootmem_core(pgdat->bdata, physaddr, size, flags);

	if (ret < 0)

		return;

	reserve_bootmem_core(pgdat->bdata, physaddr, size, flags);

}
@@ -440,7 +475,18 @@ unsigned long __init init_bootmem(unsigned long start, unsigned long pages) 
int __init reserve_bootmem(unsigned long addr, unsigned long size,

			    int flags)

{

	return reserve_bootmem_core(NODE_DATA(0)->bdata, addr, size, flags);

	bootmem_data_t *bdata;

	int ret;



	list_for_each_entry(bdata, &bdata_list, list) {

		ret = can_reserve_bootmem_core(bdata, addr, size, flags);

		if (ret < 0)

			return ret;

	}

	list_for_each_entry(bdata, &bdata_list, list)

		reserve_bootmem_core(bdata, addr, size, flags);



	return 0;

}

#endif /* !CONFIG_HAVE_ARCH_BOOTMEM_NODE */

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