diff options
Diffstat (limited to 'drivers/ieee1394/sbp2.c')
| -rw-r--r-- | drivers/ieee1394/sbp2.c | 26 |
1 files changed, 15 insertions, 11 deletions
diff --git a/drivers/ieee1394/sbp2.c b/drivers/ieee1394/sbp2.c index b91142b8482..2b889d91e67 100644 --- a/drivers/ieee1394/sbp2.c +++ b/drivers/ieee1394/sbp2.c @@ -51,6 +51,7 @@ * Grep for inline FIXME comments below. */ +#include <linux/blkdev.h> #include <linux/compiler.h> #include <linux/delay.h> #include <linux/device.h> @@ -127,17 +128,21 @@ MODULE_PARM_DESC(serialize_io, "Serialize requests coming from SCSI drivers " "(default = Y, faster but buggy = N)"); /* - * Bump up max_sectors if you'd like to support very large sized - * transfers. Please note that some older sbp2 bridge chips are broken for - * transfers greater or equal to 128KB. Default is a value of 255 - * sectors, or just under 128KB (at 512 byte sector size). I can note that - * the Oxsemi sbp2 chipsets have no problems supporting very large - * transfer sizes. + * Adjust max_sectors if you'd like to influence how many sectors each SCSI + * command can transfer at most. Please note that some older SBP-2 bridge + * chips are broken for transfers greater or equal to 128KB, therefore + * max_sectors used to be a safe 255 sectors for many years. We now have a + * default of 0 here which means that we let the SCSI stack choose a limit. + * + * The SBP2_WORKAROUND_128K_MAX_TRANS flag, if set either in the workarounds + * module parameter or in the sbp2_workarounds_table[], will override the + * value of max_sectors. We should use sbp2_workarounds_table[] to cover any + * bridge chip which becomes known to need the 255 sectors limit. */ -static int sbp2_max_sectors = SBP2_MAX_SECTORS; +static int sbp2_max_sectors; module_param_named(max_sectors, sbp2_max_sectors, int, 0444); MODULE_PARM_DESC(max_sectors, "Change max sectors per I/O supported " - "(default = " __stringify(SBP2_MAX_SECTORS) ")"); + "(default = 0 = use SCSI stack's default)"); /* * Exclusive login to sbp2 device? In most cases, the sbp2 driver should @@ -1985,6 +1990,8 @@ static int sbp2scsi_slave_configure(struct scsi_device *sdev) sdev->skip_ms_page_8 = 1; if (lu->workarounds & SBP2_WORKAROUND_FIX_CAPACITY) sdev->fix_capacity = 1; + if (lu->workarounds & SBP2_WORKAROUND_128K_MAX_TRANS) + blk_queue_max_sectors(sdev->request_queue, 128 * 1024 / 512); return 0; } @@ -2091,9 +2098,6 @@ static int sbp2_module_init(void) sbp2_shost_template.cmd_per_lun = 1; } - if (sbp2_default_workarounds & SBP2_WORKAROUND_128K_MAX_TRANS && - (sbp2_max_sectors * 512) > (128 * 1024)) - sbp2_max_sectors = 128 * 1024 / 512; sbp2_shost_template.max_sectors = sbp2_max_sectors; hpsb_register_highlevel(&sbp2_highlevel); |