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Commit f07d42ac authored by Clemens Ladisch's avatar Clemens Ladisch Committed by Stefan Richter
Browse files

firewire: core: allocate the low memory region 



Prevent userspace applications from allocating low memory address
ranges.  Otherwise, if some application happens to allocate such
a range and intends for a remote node to access it, and if that node
also implements SBP-2 (which will become more likely with the upcoming
SBP-2 target support), these accesses would be routed by the physical
DMA unit to some wrong memory address.

Signed-off-by: default avatarClemens Ladisch <clemens@ladisch.de>
Signed-off-by: default avatarStefan Richter <stefanr@s5r6.in-berlin.de>
parent 188726ec

drivers/firewire/core-transaction.c

+21 −2
Original line number Diff line number Diff line
@@ -525,9 +525,10 @@ const struct fw_address_region fw_high_memory_region = 
	{ .start = 0x000100000000ULL, .end = 0xffffe0000000ULL,  };

EXPORT_SYMBOL(fw_high_memory_region);



#if 0

const struct fw_address_region fw_low_memory_region =

static const struct fw_address_region low_memory_region =

	{ .start = 0x000000000000ULL, .end = 0x000100000000ULL,  };



#if 0

const struct fw_address_region fw_private_region =

	{ .start = 0xffffe0000000ULL, .end = 0xfffff0000000ULL,  };

const struct fw_address_region fw_csr_region =
@@ -1189,6 +1190,23 @@ static struct fw_address_handler registers = { 
	.address_callback	= handle_registers,

};



static void handle_low_memory(struct fw_card *card, struct fw_request *request,

		int tcode, int destination, int source, int generation,

		unsigned long long offset, void *payload, size_t length,

		void *callback_data)

{

	/*

	 * This catches requests not handled by the physical DMA unit,

	 * i.e., wrong transaction types or unauthorized source nodes.

	 */

	fw_send_response(card, request, RCODE_TYPE_ERROR);

}



static struct fw_address_handler low_memory = {

	.length			= 0x000100000000ULL,

	.address_callback	= handle_low_memory,

};



MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");

MODULE_DESCRIPTION("Core IEEE1394 transaction logic");

MODULE_LICENSE("GPL");
@@ -1250,6 +1268,7 @@ static int __init fw_core_init(void) 


	fw_core_add_address_handler(&topology_map, &topology_map_region);

	fw_core_add_address_handler(&registers, &registers_region);

	fw_core_add_address_handler(&low_memory, &low_memory_region);

	fw_core_add_descriptor(&vendor_id_descriptor);

	fw_core_add_descriptor(&model_id_descriptor);