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net: ipa: fix assumptions about DMA address size

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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: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Alex Elder 2021-03-18 13:59:27 -05:00 committed by David S. Miller
parent 5108802abc
commit d2fd2311de
1 changed files with 8 additions and 6 deletions
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14
drivers/net/ipa/ipa_table.c
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@ -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()