Commit d2fd2311 authored by Alex Elder's avatar Alex Elder Committed by David S. Miller
Browse files

net: ipa: fix assumptions about DMA address size 



Some build time checks in ipa_table_validate_build() assume that a
DMA address is 64 bits wide.  That is more restrictive than it has
to be.  A route or filter table is 64 bits wide no matter what the
size of a DMA address is on the AP.  The code actually uses a
pointer to __le64 to access table entries, and a fixed constant
IPA_TABLE_ENTRY_SIZE to describe the size of those entries.

Loosen up two checks so they still verify some requirements, but
such that they do not assume the size of a DMA address is 64 bits.

Signed-off-by: default avatarAlex Elder <elder@linaro.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 5108802a

drivers/net/ipa/ipa_table.c

+8 −6
Original line number Diff line number Diff line
@@ -126,13 +126,15 @@ static void ipa_table_validate_build(void) 
	 */

	BUILD_BUG_ON(ARCH_DMA_MINALIGN % IPA_TABLE_ALIGN);



	/* Filter and route tables contain DMA addresses that refer to

	 * filter or route rules.  We use a fixed constant to represent

	 * the size of either type of table entry.  Code in ipa_table_init()

	 * uses a pointer to __le64 to initialize table entriews.

	/* Filter and route tables contain DMA addresses that refer

	 * to filter or route rules.  But the size of a table entry

	 * is 64 bits regardless of what the size of an AP DMA address

	 * is.  A fixed constant defines the size of an entry, and

	 * code in ipa_table_init() uses a pointer to __le64 to

	 * initialize tables.

	 */

	BUILD_BUG_ON(IPA_TABLE_ENTRY_SIZE != sizeof(dma_addr_t));

	BUILD_BUG_ON(sizeof(dma_addr_t) != sizeof(__le64));

	BUILD_BUG_ON(sizeof(dma_addr_t) > IPA_TABLE_ENTRY_SIZE);

	BUILD_BUG_ON(sizeof(__le64) != IPA_TABLE_ENTRY_SIZE);



	/* A "zero rule" is used to represent no filtering or no routing.

	 * It is a 64-bit block of zeroed memory.  Code in ipa_table_init()