Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit b4be016a authored by Stefan Richter's avatar Stefan Richter
Browse files

firewire: fw-sbp2: fix DMA mapping of S/G tables 



  - The CPU must not touch the buffer after it was DMA-mapped.
  - The size argument of dma_unmap_single(...page_table...) was bogus.
  - Move a comment closer to the code to which it refers to.

Signed-off-by: default avatarStefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: default avatarKristian Høgsberg <krh@redhat.com>
parent 332ef331

drivers/firewire/fw-sbp2.c

+8 −11
Original line number Original line Diff line number Diff line
@@ -887,7 +887,7 @@ complete_command_orb(struct sbp2_orb *base_orb, struct sbp2_status *status) 




	if (orb->page_table_bus != 0)

	if (orb->page_table_bus != 0)

		dma_unmap_single(device->card->device, orb->page_table_bus,

		dma_unmap_single(device->card->device, orb->page_table_bus,

				 sizeof(orb->page_table_bus), DMA_TO_DEVICE);

				 sizeof(orb->page_table), DMA_TO_DEVICE);





	orb->cmd->result = result;

	orb->cmd->result = result;

	orb->done(orb->cmd);

	orb->done(orb->cmd);
@@ -902,7 +902,6 @@ static int sbp2_command_orb_map_scatterlist(struct sbp2_command_orb *orb) 
	struct fw_device *device = fw_device(unit->device.parent);

	struct fw_device *device = fw_device(unit->device.parent);

	struct scatterlist *sg;

	struct scatterlist *sg;

	int sg_len, l, i, j, count;

	int sg_len, l, i, j, count;

	size_t size;

	dma_addr_t sg_addr;

	dma_addr_t sg_addr;





	sg = (struct scatterlist *)orb->cmd->request_buffer;

	sg = (struct scatterlist *)orb->cmd->request_buffer;
@@ -951,7 +950,13 @@ static int sbp2_command_orb_map_scatterlist(struct sbp2_command_orb *orb) 
		}

		}

	}

	}





	size = sizeof(orb->page_table[0]) * j;

	fw_memcpy_to_be32(orb->page_table, orb->page_table,

			  sizeof(orb->page_table[0]) * j);

	orb->page_table_bus =

		dma_map_single(device->card->device, orb->page_table,

			       sizeof(orb->page_table), DMA_TO_DEVICE);

	if (dma_mapping_error(orb->page_table_bus))

		goto fail_page_table;





	/*

	/*

	 * The data_descriptor pointer is the one case where we need

	 * The data_descriptor pointer is the one case where we need
@@ -960,20 +965,12 @@ static int sbp2_command_orb_map_scatterlist(struct sbp2_command_orb *orb) 
	 * initiator (i.e. us), but data_descriptor can refer to data

	 * initiator (i.e. us), but data_descriptor can refer to data

	 * on other nodes so we need to put our ID in descriptor.high.

	 * on other nodes so we need to put our ID in descriptor.high.

	 */

	 */



	orb->page_table_bus =

		dma_map_single(device->card->device, orb->page_table,

			       size, DMA_TO_DEVICE);

	if (dma_mapping_error(orb->page_table_bus))

		goto fail_page_table;

	orb->request.data_descriptor.high = sd->address_high;

	orb->request.data_descriptor.high = sd->address_high;

	orb->request.data_descriptor.low  = orb->page_table_bus;

	orb->request.data_descriptor.low  = orb->page_table_bus;

	orb->request.misc |=

	orb->request.misc |=

		COMMAND_ORB_PAGE_TABLE_PRESENT |

		COMMAND_ORB_PAGE_TABLE_PRESENT |

		COMMAND_ORB_DATA_SIZE(j);

		COMMAND_ORB_DATA_SIZE(j);





	fw_memcpy_to_be32(orb->page_table, orb->page_table, size);



	return 0;

	return 0;





 fail_page_table:

 fail_page_table: