diff options
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/firewire/fw-sbp2.c | 63 |
1 files changed, 27 insertions, 36 deletions
diff --git a/drivers/firewire/fw-sbp2.c b/drivers/firewire/fw-sbp2.c index 05997ce..5d8411a 100644 --- a/drivers/firewire/fw-sbp2.c +++ b/drivers/firewire/fw-sbp2.c @@ -29,6 +29,7 @@ */ #include <linux/blkdev.h> +#include <linux/bug.h> #include <linux/delay.h> #include <linux/device.h> #include <linux/dma-mapping.h> @@ -181,10 +182,16 @@ struct sbp2_target { #define SBP2_MAX_LOGIN_ORB_TIMEOUT 40000U /* Timeout in ms */ #define SBP2_ORB_TIMEOUT 2000U /* Timeout in ms */ #define SBP2_ORB_NULL 0x80000000 -#define SBP2_MAX_SG_ELEMENT_LENGTH 0xf000 #define SBP2_RETRY_LIMIT 0xf /* 15 retries */ #define SBP2_CYCLE_LIMIT (0xc8 << 12) /* 200 125us cycles */ +/* + * The default maximum s/g segment size of a FireWire controller is + * usually 0x10000, but SBP-2 only allows 0xffff. Since buffers have to + * be quadlet-aligned, we set the length limit to 0xffff & ~3. + */ +#define SBP2_MAX_SEG_SIZE 0xfffc + /* Unit directory keys */ #define SBP2_CSR_UNIT_CHARACTERISTICS 0x3a #define SBP2_CSR_FIRMWARE_REVISION 0x3c @@ -1099,6 +1106,10 @@ static int sbp2_probe(struct device *dev) struct Scsi_Host *shost; u32 model, firmware_revision; + if (dma_get_max_seg_size(device->card->device) > SBP2_MAX_SEG_SIZE) + BUG_ON(dma_set_max_seg_size(device->card->device, + SBP2_MAX_SEG_SIZE)); + shost = scsi_host_alloc(&scsi_driver_template, sizeof(*tgt)); if (shost == NULL) return -ENOMEM; @@ -1347,14 +1358,12 @@ static int sbp2_map_scatterlist(struct sbp2_command_orb *orb, struct fw_device *device, struct sbp2_logical_unit *lu) { - struct scatterlist *sg; - int sg_len, l, i, j, count; - dma_addr_t sg_addr; - - sg = scsi_sglist(orb->cmd); - count = dma_map_sg(device->card->device, sg, scsi_sg_count(orb->cmd), - orb->cmd->sc_data_direction); - if (count == 0) + struct scatterlist *sg = scsi_sglist(orb->cmd); + int i, n; + + n = dma_map_sg(device->card->device, sg, scsi_sg_count(orb->cmd), + orb->cmd->sc_data_direction); + if (n == 0) goto fail; /* @@ -1364,7 +1373,7 @@ sbp2_map_scatterlist(struct sbp2_command_orb *orb, struct fw_device *device, * as the second generation iPod which doesn't support page * tables. */ - if (count == 1 && sg_dma_len(sg) < SBP2_MAX_SG_ELEMENT_LENGTH) { + if (n == 1) { orb->request.data_descriptor.high = cpu_to_be32(lu->tgt->address_high); orb->request.data_descriptor.low = @@ -1374,29 +1383,9 @@ sbp2_map_scatterlist(struct sbp2_command_orb *orb, struct fw_device *device, return 0; } - /* - * Convert the scatterlist to an sbp2 page table. If any - * scatterlist entries are too big for sbp2, we split them as we - * go. Even if we ask the block I/O layer to not give us sg - * elements larger than 65535 bytes, some IOMMUs may merge sg elements - * during DMA mapping, and Linux currently doesn't prevent this. - */ - for (i = 0, j = 0; i < count; i++, sg = sg_next(sg)) { - sg_len = sg_dma_len(sg); - sg_addr = sg_dma_address(sg); - while (sg_len) { - /* FIXME: This won't get us out of the pinch. */ - if (unlikely(j >= ARRAY_SIZE(orb->page_table))) { - fw_error("page table overflow\n"); - goto fail_page_table; - } - l = min(sg_len, SBP2_MAX_SG_ELEMENT_LENGTH); - orb->page_table[j].low = cpu_to_be32(sg_addr); - orb->page_table[j].high = cpu_to_be32(l << 16); - sg_addr += l; - sg_len -= l; - j++; - } + for_each_sg(sg, sg, n, i) { + orb->page_table[i].high = cpu_to_be32(sg_dma_len(sg) << 16); + orb->page_table[i].low = cpu_to_be32(sg_dma_address(sg)); } orb->page_table_bus = @@ -1415,13 +1404,13 @@ sbp2_map_scatterlist(struct sbp2_command_orb *orb, struct fw_device *device, orb->request.data_descriptor.high = cpu_to_be32(lu->tgt->address_high); orb->request.data_descriptor.low = cpu_to_be32(orb->page_table_bus); orb->request.misc |= cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT | - COMMAND_ORB_DATA_SIZE(j)); + COMMAND_ORB_DATA_SIZE(n)); return 0; fail_page_table: - dma_unmap_sg(device->card->device, sg, scsi_sg_count(orb->cmd), - orb->cmd->sc_data_direction); + dma_unmap_sg(device->card->device, scsi_sglist(orb->cmd), + scsi_sg_count(orb->cmd), orb->cmd->sc_data_direction); fail: return -ENOMEM; } @@ -1542,6 +1531,8 @@ static int sbp2_scsi_slave_configure(struct scsi_device *sdev) if (lu->tgt->workarounds & SBP2_WORKAROUND_128K_MAX_TRANS) blk_queue_max_sectors(sdev->request_queue, 128 * 1024 / 512); + blk_queue_max_segment_size(sdev->request_queue, SBP2_MAX_SEG_SIZE); + return 0; } |