Commit 8e80632f authored by Matt Fleming's avatar Matt Fleming
Browse files

efi/esrt: Use efi_mem_reserve() and avoid a kmalloc() 



We can use the new efi_mem_reserve() API to mark the ESRT table as
reserved forever and save ourselves the trouble of copying the data
out into a kmalloc buffer.

The added advantage is that now the ESRT driver will work across
kexec reboot.

Tested-by: Dave Young <dyoung@redhat.com> [kexec/kdump]
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> [arm]
Acked-by: default avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Peter Jones <pjones@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: default avatarMatt Fleming <matt@codeblueprint.co.uk>
parent 31ce8cc6

drivers/firmware/efi/esrt.c

+4 −16
Original line number Original line Diff line number Diff line
@@ -235,7 +235,7 @@ static struct attribute_group esrt_attr_group = { 
};

};





/*

/*

 * remap the table, copy it to kmalloced pages, and unmap it.

 * remap the table, validate it, mark it reserved and unmap it.

 */

 */

void __init efi_esrt_init(void)

void __init efi_esrt_init(void)

{

{
@@ -335,7 +335,7 @@ void __init efi_esrt_init(void) 




	end = esrt_data + size;

	end = esrt_data + size;

	pr_info("Reserving ESRT space from %pa to %pa.\n", &esrt_data, &end);

	pr_info("Reserving ESRT space from %pa to %pa.\n", &esrt_data, &end);

	memblock_reserve(esrt_data, esrt_data_size);

	efi_mem_reserve(esrt_data, esrt_data_size);





	pr_debug("esrt-init: loaded.\n");

	pr_debug("esrt-init: loaded.\n");

err_memunmap:

err_memunmap:
@@ -382,28 +382,18 @@ static void cleanup_entry_list(void) 
static int __init esrt_sysfs_init(void)

static int __init esrt_sysfs_init(void)

{

{

	int error;

	int error;

	struct efi_system_resource_table __iomem *ioesrt;





	pr_debug("esrt-sysfs: loading.\n");

	pr_debug("esrt-sysfs: loading.\n");

	if (!esrt_data || !esrt_data_size)

	if (!esrt_data || !esrt_data_size)

		return -ENOSYS;

		return -ENOSYS;





	ioesrt = ioremap(esrt_data, esrt_data_size);

	esrt = ioremap(esrt_data, esrt_data_size);

	if (!ioesrt) {

	if (!esrt) {

		pr_err("ioremap(%pa, %zu) failed.\n", &esrt_data,

		pr_err("ioremap(%pa, %zu) failed.\n", &esrt_data,

		       esrt_data_size);

		       esrt_data_size);

		return -ENOMEM;

		return -ENOMEM;

	}

	}





	esrt = kmalloc(esrt_data_size, GFP_KERNEL);

	if (!esrt) {

		pr_err("kmalloc failed. (wanted %zu bytes)\n", esrt_data_size);

		iounmap(ioesrt);

		return -ENOMEM;

	}



	memcpy_fromio(esrt, ioesrt, esrt_data_size);



	esrt_kobj = kobject_create_and_add("esrt", efi_kobj);

	esrt_kobj = kobject_create_and_add("esrt", efi_kobj);

	if (!esrt_kobj) {

	if (!esrt_kobj) {

		pr_err("Firmware table registration failed.\n");

		pr_err("Firmware table registration failed.\n");
@@ -429,8 +419,6 @@ static int __init esrt_sysfs_init(void) 
	if (error)

	if (error)

		goto err_cleanup_list;

		goto err_cleanup_list;





	memblock_remove(esrt_data, esrt_data_size);



	pr_debug("esrt-sysfs: loaded.\n");

	pr_debug("esrt-sysfs: loaded.\n");





	return 0;

	return 0;

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