Commit c1a2f4b1 authored by Yinghai Lu's avatar Yinghai Lu Committed by Ingo Molnar
Browse files

x86: change early_ioremap to use slots instead of nesting 



so we could remove the requirement that one needs to call
early_iounmap() in exactly reverse order of early_ioremap().

Signed-off-by: default avatarYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 79aa10dd

arch/x86/mm/ioremap.c

+57 −20
Original line number Original line Diff line number Diff line
@@ -616,16 +616,22 @@ static inline void __init early_clear_fixmap(enum fixed_addresses idx) 
		__early_set_fixmap(idx, 0, __pgprot(0));

		__early_set_fixmap(idx, 0, __pgprot(0));

}

}







static void *prev_map[FIX_BTMAPS_SLOTS] __initdata;

static int __initdata early_ioremap_nested;

static unsigned long prev_size[FIX_BTMAPS_SLOTS] __initdata;



static int __init check_early_ioremap_leak(void)

static int __init check_early_ioremap_leak(void)

{

{

	if (!early_ioremap_nested)

	int count = 0;

	int i;



	for (i = 0; i < FIX_BTMAPS_SLOTS; i++)

		if (prev_map[i])

			count++;



	if (!count)

		return 0;

		return 0;

	WARN(1, KERN_WARNING

	WARN(1, KERN_WARNING

	       "Debug warning: early ioremap leak of %d areas detected.\n",

	       "Debug warning: early ioremap leak of %d areas detected.\n",

		early_ioremap_nested);

		count);

	printk(KERN_WARNING

	printk(KERN_WARNING

		"please boot with early_ioremap_debug and report the dmesg.\n");

		"please boot with early_ioremap_debug and report the dmesg.\n");
@@ -636,15 +642,30 @@ late_initcall(check_early_ioremap_leak); 
static void __init *__early_ioremap(unsigned long phys_addr, unsigned long size, pgprot_t prot)

static void __init *__early_ioremap(unsigned long phys_addr, unsigned long size, pgprot_t prot)

{

{

	unsigned long offset, last_addr;

	unsigned long offset, last_addr;

	unsigned int nrpages, nesting;

	unsigned int nrpages;

	enum fixed_addresses idx0, idx;

	enum fixed_addresses idx0, idx;

	int i, slot;





	WARN_ON(system_state != SYSTEM_BOOTING);

	WARN_ON(system_state != SYSTEM_BOOTING);





	nesting = early_ioremap_nested;

	slot = -1;

	for (i = 0; i < FIX_BTMAPS_SLOTS; i++) {

		if (!prev_map[i]) {

			slot = i;

			break;

		}

	}



	if (slot < 0) {

		printk(KERN_INFO "early_iomap(%08lx, %08lx) not found slot\n",

			 phys_addr, size);

		WARN_ON(1);

		return NULL;

	}



	if (early_ioremap_debug) {

	if (early_ioremap_debug) {

		printk(KERN_INFO "early_ioremap(%08lx, %08lx) [%d] => ",

		printk(KERN_INFO "early_ioremap(%08lx, %08lx) [%d] => ",

		       phys_addr, size, nesting);

		       phys_addr, size, slot);

		dump_stack();

		dump_stack();

	}

	}
@@ -655,11 +676,7 @@ static void __init *__early_ioremap(unsigned long phys_addr, unsigned long size, 
		return NULL;

		return NULL;

	}

	}





	if (nesting >= FIX_BTMAPS_NESTING) {

	prev_size[slot] = size;

		WARN_ON(1);

		return NULL;

	}

	early_ioremap_nested++;

	/*

	/*

	 * Mappings have to be page-aligned

	 * Mappings have to be page-aligned

	 */

	 */
@@ -679,7 +696,7 @@ static void __init *__early_ioremap(unsigned long phys_addr, unsigned long size, 
	/*

	/*

	 * Ok, go for it..

	 * Ok, go for it..

	 */

	 */

	idx0 = FIX_BTMAP_BEGIN - NR_FIX_BTMAPS*nesting;

	idx0 = FIX_BTMAP_BEGIN - NR_FIX_BTMAPS*slot;

	idx = idx0;

	idx = idx0;

	while (nrpages > 0) {

	while (nrpages > 0) {

		early_set_fixmap(idx, phys_addr, prot);

		early_set_fixmap(idx, phys_addr, prot);
@@ -690,7 +707,8 @@ static void __init *__early_ioremap(unsigned long phys_addr, unsigned long size, 
	if (early_ioremap_debug)

	if (early_ioremap_debug)

		printk(KERN_CONT "%08lx + %08lx\n", offset, fix_to_virt(idx0));

		printk(KERN_CONT "%08lx + %08lx\n", offset, fix_to_virt(idx0));





	return (void *) (offset + fix_to_virt(idx0));

	prev_map[slot] = (void *) (offset + fix_to_virt(idx0));

	return prev_map[slot];

}

}





/* Remap an IO device */

/* Remap an IO device */
@@ -711,15 +729,33 @@ void __init early_iounmap(void *addr, unsigned long size) 
	unsigned long offset;

	unsigned long offset;

	unsigned int nrpages;

	unsigned int nrpages;

	enum fixed_addresses idx;

	enum fixed_addresses idx;

	int nesting;

	int i, slot;



	slot = -1;

	for (i = 0; i < FIX_BTMAPS_SLOTS; i++) {

		if (prev_map[i] == addr) {

			slot = i;

			break;

		}

	}





	nesting = --early_ioremap_nested;

	if (slot < 0) {

	if (WARN_ON(nesting < 0))

		printk(KERN_INFO "early_iounmap(%p, %08lx) not found slot\n",

			 addr, size);

		WARN_ON(1);

		return;

	}



	if (prev_size[slot] != size) {

		printk(KERN_INFO "early_iounmap(%p, %08lx) [%d] size not consistent %08lx\n",

			 addr, size, slot, prev_size[slot]);

		WARN_ON(1);

		return;

		return;

	}





	if (early_ioremap_debug) {

	if (early_ioremap_debug) {

		printk(KERN_INFO "early_iounmap(%p, %08lx) [%d]\n", addr,

		printk(KERN_INFO "early_iounmap(%p, %08lx) [%d]\n", addr,

		       size, nesting);

		       size, slot);

		dump_stack();

		dump_stack();

	}

	}
@@ -731,12 +767,13 @@ void __init early_iounmap(void *addr, unsigned long size) 
	offset = virt_addr & ~PAGE_MASK;

	offset = virt_addr & ~PAGE_MASK;

	nrpages = PAGE_ALIGN(offset + size - 1) >> PAGE_SHIFT;

	nrpages = PAGE_ALIGN(offset + size - 1) >> PAGE_SHIFT;





	idx = FIX_BTMAP_BEGIN - NR_FIX_BTMAPS*nesting;

	idx = FIX_BTMAP_BEGIN - NR_FIX_BTMAPS*slot;

	while (nrpages > 0) {

	while (nrpages > 0) {

		early_clear_fixmap(idx);

		early_clear_fixmap(idx);

		--idx;

		--idx;

		--nrpages;

		--nrpages;

	}

	}

	prev_map[slot] = 0;

}

}





void __this_fixmap_does_not_exist(void)

void __this_fixmap_does_not_exist(void)

include/asm-x86/fixmap_32.h

+2 −2
Original line number Original line Diff line number Diff line
@@ -94,10 +94,10 @@ enum fixed_addresses { 
	 * can have a single pgd entry and a single pte table:

	 * can have a single pgd entry and a single pte table:

	 */

	 */

#define NR_FIX_BTMAPS		64

#define NR_FIX_BTMAPS		64

#define FIX_BTMAPS_NESTING	4

#define FIX_BTMAPS_SLOTS	4

	FIX_BTMAP_END = __end_of_permanent_fixed_addresses + 256 -

	FIX_BTMAP_END = __end_of_permanent_fixed_addresses + 256 -

			(__end_of_permanent_fixed_addresses & 255),

			(__end_of_permanent_fixed_addresses & 255),

	FIX_BTMAP_BEGIN = FIX_BTMAP_END + NR_FIX_BTMAPS*FIX_BTMAPS_NESTING - 1,

	FIX_BTMAP_BEGIN = FIX_BTMAP_END + NR_FIX_BTMAPS*FIX_BTMAPS_SLOTS - 1,

	FIX_WP_TEST,

	FIX_WP_TEST,

#ifdef CONFIG_ACPI

#ifdef CONFIG_ACPI

	FIX_ACPI_BEGIN,

	FIX_ACPI_BEGIN,

include/asm-x86/fixmap_64.h

+2 −2
Original line number Original line Diff line number Diff line
@@ -65,10 +65,10 @@ enum fixed_addresses { 
	 * can have a single pgd entry and a single pte table:

	 * can have a single pgd entry and a single pte table:

	 */

	 */

#define NR_FIX_BTMAPS		64

#define NR_FIX_BTMAPS		64

#define FIX_BTMAPS_NESTING	4

#define FIX_BTMAPS_SLOTS	4

	FIX_BTMAP_END = __end_of_permanent_fixed_addresses + 256 -

	FIX_BTMAP_END = __end_of_permanent_fixed_addresses + 256 -

			(__end_of_permanent_fixed_addresses & 255),

			(__end_of_permanent_fixed_addresses & 255),

	FIX_BTMAP_BEGIN = FIX_BTMAP_END + NR_FIX_BTMAPS*FIX_BTMAPS_NESTING - 1,

	FIX_BTMAP_BEGIN = FIX_BTMAP_END + NR_FIX_BTMAPS*FIX_BTMAPS_SLOTS - 1,

	__end_of_fixed_addresses

	__end_of_fixed_addresses

};

};