[SCSI] remove use_sg_chaining
With the sg table code, every SCSI driver is now either chain capable
or broken (or has sg_tablesize set so chaining is never activated), so
there's no need to have a check in the host template.
Also tidy up the code by moving the scatterlist size defines into the
SCSI includes and permit the last entry of the scatterlist pools not
to be a power of two.
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/arch/ia64/hp/sim/simscsi.c b/arch/ia64/hp/sim/simscsi.c
index 6ef9b52..7661bb0 100644
--- a/arch/ia64/hp/sim/simscsi.c
+++ b/arch/ia64/hp/sim/simscsi.c
@@ -360,7 +360,6 @@
.max_sectors = 1024,
.cmd_per_lun = SIMSCSI_REQ_QUEUE_LEN,
.use_clustering = DISABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
};
static int __init
diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c
index f2d2c7e..195ce7c 100644
--- a/drivers/infiniband/ulp/srp/ib_srp.c
+++ b/drivers/infiniband/ulp/srp/ib_srp.c
@@ -1571,7 +1571,6 @@
.this_id = -1,
.cmd_per_lun = SRP_SQ_SIZE,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
.shost_attrs = srp_host_attrs
};
diff --git a/drivers/scsi/3w-9xxx.c b/drivers/scsi/3w-9xxx.c
index 1c24483..b4912d1 100644
--- a/drivers/scsi/3w-9xxx.c
+++ b/drivers/scsi/3w-9xxx.c
@@ -1990,7 +1990,6 @@
.max_sectors = TW_MAX_SECTORS,
.cmd_per_lun = TW_MAX_CMDS_PER_LUN,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
.shost_attrs = twa_host_attrs,
.emulated = 1
};
diff --git a/drivers/scsi/3w-xxxx.c b/drivers/scsi/3w-xxxx.c
index 59716eb..d095321 100644
--- a/drivers/scsi/3w-xxxx.c
+++ b/drivers/scsi/3w-xxxx.c
@@ -2261,7 +2261,6 @@
.max_sectors = TW_MAX_SECTORS,
.cmd_per_lun = TW_MAX_CMDS_PER_LUN,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
.shost_attrs = tw_host_attrs,
.emulated = 1
};
diff --git a/drivers/scsi/BusLogic.c b/drivers/scsi/BusLogic.c
index ead47c1..4d3ebb1 100644
--- a/drivers/scsi/BusLogic.c
+++ b/drivers/scsi/BusLogic.c
@@ -3575,7 +3575,6 @@
.unchecked_isa_dma = 1,
.max_sectors = 128,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
};
/*
diff --git a/drivers/scsi/NCR53c406a.c b/drivers/scsi/NCR53c406a.c
index 137d065..6961f78 100644
--- a/drivers/scsi/NCR53c406a.c
+++ b/drivers/scsi/NCR53c406a.c
@@ -1065,7 +1065,6 @@
.cmd_per_lun = 1 /* commands per lun */,
.unchecked_isa_dma = 1 /* unchecked_isa_dma */,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
};
#include "scsi_module.c"
diff --git a/drivers/scsi/a100u2w.c b/drivers/scsi/a100u2w.c
index d3a6d15..f608d4a 100644
--- a/drivers/scsi/a100u2w.c
+++ b/drivers/scsi/a100u2w.c
@@ -1071,7 +1071,6 @@
.sg_tablesize = SG_ALL,
.cmd_per_lun = 1,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
};
static int __devinit inia100_probe_one(struct pci_dev *pdev,
diff --git a/drivers/scsi/aacraid/linit.c b/drivers/scsi/aacraid/linit.c
index 61be227..0e8267c 100644
--- a/drivers/scsi/aacraid/linit.c
+++ b/drivers/scsi/aacraid/linit.c
@@ -1032,7 +1032,6 @@
.cmd_per_lun = AAC_NUM_IO_FIB,
#endif
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
.emulated = 1,
};
diff --git a/drivers/scsi/aha1740.c b/drivers/scsi/aha1740.c
index be58a0b..7c45d88 100644
--- a/drivers/scsi/aha1740.c
+++ b/drivers/scsi/aha1740.c
@@ -563,7 +563,6 @@
.sg_tablesize = AHA1740_SCATTER,
.cmd_per_lun = AHA1740_CMDLUN,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
.eh_abort_handler = aha1740_eh_abort_handler,
};
diff --git a/drivers/scsi/aic7xxx/aic79xx_osm.c b/drivers/scsi/aic7xxx/aic79xx_osm.c
index 3c4efa4..0146547 100644
--- a/drivers/scsi/aic7xxx/aic79xx_osm.c
+++ b/drivers/scsi/aic7xxx/aic79xx_osm.c
@@ -766,7 +766,6 @@
.max_sectors = 8192,
.cmd_per_lun = 2,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
.slave_alloc = ahd_linux_slave_alloc,
.slave_configure = ahd_linux_slave_configure,
.target_alloc = ahd_linux_target_alloc,
diff --git a/drivers/scsi/aic7xxx/aic7xxx_osm.c b/drivers/scsi/aic7xxx/aic7xxx_osm.c
index bff7f8c..99a3b33 100644
--- a/drivers/scsi/aic7xxx/aic7xxx_osm.c
+++ b/drivers/scsi/aic7xxx/aic7xxx_osm.c
@@ -747,7 +747,6 @@
.max_sectors = 8192,
.cmd_per_lun = 2,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
.slave_alloc = ahc_linux_slave_alloc,
.slave_configure = ahc_linux_slave_configure,
.target_alloc = ahc_linux_target_alloc,
diff --git a/drivers/scsi/aic7xxx_old.c b/drivers/scsi/aic7xxx_old.c
index bcb0b87..3bfd929 100644
--- a/drivers/scsi/aic7xxx_old.c
+++ b/drivers/scsi/aic7xxx_old.c
@@ -11141,7 +11141,6 @@
.max_sectors = 2048,
.cmd_per_lun = 3,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
};
#include "scsi_module.c"
diff --git a/drivers/scsi/arcmsr/arcmsr_hba.c b/drivers/scsi/arcmsr/arcmsr_hba.c
index d80dba9..f4a202e 100644
--- a/drivers/scsi/arcmsr/arcmsr_hba.c
+++ b/drivers/scsi/arcmsr/arcmsr_hba.c
@@ -122,7 +122,6 @@
.max_sectors = ARCMSR_MAX_XFER_SECTORS,
.cmd_per_lun = ARCMSR_MAX_CMD_PERLUN,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
.shost_attrs = arcmsr_host_attrs,
};
#ifdef CONFIG_SCSI_ARCMSR_AER
diff --git a/drivers/scsi/dc395x.c b/drivers/scsi/dc395x.c
index f93c73c..22ef371 100644
--- a/drivers/scsi/dc395x.c
+++ b/drivers/scsi/dc395x.c
@@ -4763,7 +4763,6 @@
.eh_bus_reset_handler = dc395x_eh_bus_reset,
.unchecked_isa_dma = 0,
.use_clustering = DISABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
};
diff --git a/drivers/scsi/dpt_i2o.c b/drivers/scsi/dpt_i2o.c
index 19cce12..c9dd839 100644
--- a/drivers/scsi/dpt_i2o.c
+++ b/drivers/scsi/dpt_i2o.c
@@ -3340,7 +3340,6 @@
.this_id = 7,
.cmd_per_lun = 1,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
};
#include "scsi_module.c"
MODULE_LICENSE("GPL");
diff --git a/drivers/scsi/eata.c b/drivers/scsi/eata.c
index 05163ce..8be3d76 100644
--- a/drivers/scsi/eata.c
+++ b/drivers/scsi/eata.c
@@ -524,7 +524,6 @@
.this_id = 7,
.unchecked_isa_dma = 1,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
};
#if !defined(__BIG_ENDIAN_BITFIELD) && !defined(__LITTLE_ENDIAN_BITFIELD)
diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c
index 5ea1f98..880c78b 100644
--- a/drivers/scsi/hosts.c
+++ b/drivers/scsi/hosts.c
@@ -342,7 +342,6 @@
shost->use_clustering = sht->use_clustering;
shost->ordered_tag = sht->ordered_tag;
shost->active_mode = sht->supported_mode;
- shost->use_sg_chaining = sht->use_sg_chaining;
if (sht->supported_mode == MODE_UNKNOWN)
/* means we didn't set it ... default to INITIATOR */
diff --git a/drivers/scsi/hptiop.c b/drivers/scsi/hptiop.c
index 890f44f..ff149ad 100644
--- a/drivers/scsi/hptiop.c
+++ b/drivers/scsi/hptiop.c
@@ -906,7 +906,6 @@
.unchecked_isa_dma = 0,
.emulated = 0,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
.proc_name = driver_name,
.shost_attrs = hptiop_attrs,
.this_id = -1,
diff --git a/drivers/scsi/ibmmca.c b/drivers/scsi/ibmmca.c
index db004a4..4d15a62 100644
--- a/drivers/scsi/ibmmca.c
+++ b/drivers/scsi/ibmmca.c
@@ -1501,7 +1501,6 @@
.sg_tablesize = 16,
.cmd_per_lun = 1,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
};
static int ibmmca_probe(struct device *dev)
diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c
index 3081901..78d46a9 100644
--- a/drivers/scsi/ibmvscsi/ibmvscsi.c
+++ b/drivers/scsi/ibmvscsi/ibmvscsi.c
@@ -1600,7 +1600,6 @@
.this_id = -1,
.sg_tablesize = SG_ALL,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
.shost_attrs = ibmvscsi_attrs,
};
diff --git a/drivers/scsi/initio.c b/drivers/scsi/initio.c
index a10a5c7..0cc8868 100644
--- a/drivers/scsi/initio.c
+++ b/drivers/scsi/initio.c
@@ -2833,7 +2833,6 @@
.sg_tablesize = SG_ALL,
.cmd_per_lun = 1,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
};
static int initio_probe_one(struct pci_dev *pdev,
diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
index e5be5fd..b6f99df 100644
--- a/drivers/scsi/iscsi_tcp.c
+++ b/drivers/scsi/iscsi_tcp.c
@@ -1933,7 +1933,6 @@
.eh_device_reset_handler= iscsi_eh_device_reset,
.eh_host_reset_handler = iscsi_eh_host_reset,
.use_clustering = DISABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
.slave_configure = iscsi_tcp_slave_configure,
.proc_name = "iscsi_tcp",
.this_id = -1,
diff --git a/drivers/scsi/lpfc/lpfc_scsi.c b/drivers/scsi/lpfc/lpfc_scsi.c
index 6483c62..fc5c3a4 100644
--- a/drivers/scsi/lpfc/lpfc_scsi.c
+++ b/drivers/scsi/lpfc/lpfc_scsi.c
@@ -1459,7 +1459,6 @@
.scan_finished = lpfc_scan_finished,
.this_id = -1,
.sg_tablesize = LPFC_DEFAULT_SG_SEG_CNT,
- .use_sg_chaining = ENABLE_SG_CHAINING,
.cmd_per_lun = LPFC_CMD_PER_LUN,
.use_clustering = ENABLE_CLUSTERING,
.shost_attrs = lpfc_hba_attrs,
@@ -1482,7 +1481,6 @@
.sg_tablesize = LPFC_DEFAULT_SG_SEG_CNT,
.cmd_per_lun = LPFC_CMD_PER_LUN,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
.shost_attrs = lpfc_vport_attrs,
.max_sectors = 0xFFFF,
};
diff --git a/drivers/scsi/mac53c94.c b/drivers/scsi/mac53c94.c
index a035001..b12ad7c 100644
--- a/drivers/scsi/mac53c94.c
+++ b/drivers/scsi/mac53c94.c
@@ -402,7 +402,6 @@
.sg_tablesize = SG_ALL,
.cmd_per_lun = 1,
.use_clustering = DISABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
};
static int mac53c94_probe(struct macio_dev *mdev, const struct of_device_id *match)
diff --git a/drivers/scsi/megaraid.c b/drivers/scsi/megaraid.c
index 765c24d..4d59ae8 100644
--- a/drivers/scsi/megaraid.c
+++ b/drivers/scsi/megaraid.c
@@ -4490,7 +4490,6 @@
.sg_tablesize = MAX_SGLIST,
.cmd_per_lun = DEF_CMD_PER_LUN,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
.eh_abort_handler = megaraid_abort,
.eh_device_reset_handler = megaraid_reset,
.eh_bus_reset_handler = megaraid_reset,
diff --git a/drivers/scsi/megaraid/megaraid_mbox.c b/drivers/scsi/megaraid/megaraid_mbox.c
index 24e32e4..6db77c0 100644
--- a/drivers/scsi/megaraid/megaraid_mbox.c
+++ b/drivers/scsi/megaraid/megaraid_mbox.c
@@ -361,7 +361,6 @@
.eh_host_reset_handler = megaraid_reset_handler,
.change_queue_depth = megaraid_change_queue_depth,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
.sdev_attrs = megaraid_sdev_attrs,
.shost_attrs = megaraid_shost_attrs,
};
diff --git a/drivers/scsi/megaraid/megaraid_sas.c b/drivers/scsi/megaraid/megaraid_sas.c
index d7ec921..672c759 100644
--- a/drivers/scsi/megaraid/megaraid_sas.c
+++ b/drivers/scsi/megaraid/megaraid_sas.c
@@ -1192,7 +1192,6 @@
.eh_timed_out = megasas_reset_timer,
.bios_param = megasas_bios_param,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
};
/**
diff --git a/drivers/scsi/mesh.c b/drivers/scsi/mesh.c
index 7470ff3..651d09b 100644
--- a/drivers/scsi/mesh.c
+++ b/drivers/scsi/mesh.c
@@ -1843,7 +1843,6 @@
.sg_tablesize = SG_ALL,
.cmd_per_lun = 2,
.use_clustering = DISABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
};
static int mesh_probe(struct macio_dev *mdev, const struct of_device_id *match)
diff --git a/drivers/scsi/nsp32.c b/drivers/scsi/nsp32.c
index 28161dc..7fed353 100644
--- a/drivers/scsi/nsp32.c
+++ b/drivers/scsi/nsp32.c
@@ -281,7 +281,6 @@
.cmd_per_lun = 1,
.this_id = NSP32_HOST_SCSIID,
.use_clustering = DISABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
.eh_abort_handler = nsp32_eh_abort,
.eh_bus_reset_handler = nsp32_eh_bus_reset,
.eh_host_reset_handler = nsp32_eh_host_reset,
diff --git a/drivers/scsi/pcmcia/sym53c500_cs.c b/drivers/scsi/pcmcia/sym53c500_cs.c
index 969b938..3454a57 100644
--- a/drivers/scsi/pcmcia/sym53c500_cs.c
+++ b/drivers/scsi/pcmcia/sym53c500_cs.c
@@ -692,7 +692,6 @@
.sg_tablesize = 32,
.cmd_per_lun = 1,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
.shost_attrs = SYM53C500_shost_attrs
};
diff --git a/drivers/scsi/qla1280.c b/drivers/scsi/qla1280.c
index c94906a..68c0d09 100644
--- a/drivers/scsi/qla1280.c
+++ b/drivers/scsi/qla1280.c
@@ -4204,7 +4204,6 @@
.sg_tablesize = SG_ALL,
.cmd_per_lun = 1,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
};
diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c
index aba1e6d..3954ed2 100644
--- a/drivers/scsi/qla2xxx/qla_os.c
+++ b/drivers/scsi/qla2xxx/qla_os.c
@@ -131,7 +131,6 @@
.this_id = -1,
.cmd_per_lun = 3,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
.sg_tablesize = SG_ALL,
/*
@@ -163,7 +162,6 @@
.this_id = -1,
.cmd_per_lun = 3,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
.sg_tablesize = SG_ALL,
.max_sectors = 0xFFFF,
diff --git a/drivers/scsi/qla4xxx/ql4_os.c b/drivers/scsi/qla4xxx/ql4_os.c
index d3f8664..2e2b9fe 100644
--- a/drivers/scsi/qla4xxx/ql4_os.c
+++ b/drivers/scsi/qla4xxx/ql4_os.c
@@ -94,7 +94,6 @@
.this_id = -1,
.cmd_per_lun = 3,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
.sg_tablesize = SG_ALL,
.max_sectors = 0xFFFF,
diff --git a/drivers/scsi/qlogicfas.c b/drivers/scsi/qlogicfas.c
index 1769f96..1e874f1 100644
--- a/drivers/scsi/qlogicfas.c
+++ b/drivers/scsi/qlogicfas.c
@@ -197,7 +197,6 @@
.sg_tablesize = SG_ALL,
.cmd_per_lun = 1,
.use_clustering = DISABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
};
static __init int qlogicfas_init(void)
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 4560713..e1c7eeb 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -8,6 +8,7 @@
*/
#include <linux/bio.h>
+#include <linux/bitops.h>
#include <linux/blkdev.h>
#include <linux/completion.h>
#include <linux/kernel.h>
@@ -34,13 +35,6 @@
#define SG_MEMPOOL_NR ARRAY_SIZE(scsi_sg_pools)
#define SG_MEMPOOL_SIZE 2
-/*
- * The maximum number of SG segments that we will put inside a scatterlist
- * (unless chaining is used). Should ideally fit inside a single page, to
- * avoid a higher order allocation.
- */
-#define SCSI_MAX_SG_SEGMENTS 128
-
struct scsi_host_sg_pool {
size_t size;
char *name;
@@ -48,19 +42,26 @@
mempool_t *pool;
};
-#define SP(x) { x, "sgpool-" #x }
+#define SP(x) { x, "sgpool-" __stringify(x) }
+#if (SCSI_MAX_SG_SEGMENTS < 32)
+#error SCSI_MAX_SG_SEGMENTS is too small (must be 32 or greater)
+#endif
static struct scsi_host_sg_pool scsi_sg_pools[] = {
SP(8),
SP(16),
-#if (SCSI_MAX_SG_SEGMENTS > 16)
- SP(32),
#if (SCSI_MAX_SG_SEGMENTS > 32)
- SP(64),
+ SP(32),
#if (SCSI_MAX_SG_SEGMENTS > 64)
+ SP(64),
+#if (SCSI_MAX_SG_SEGMENTS > 128)
SP(128),
+#if (SCSI_MAX_SG_SEGMENTS > 256)
+#error SCSI_MAX_SG_SEGMENTS is too large (256 MAX)
#endif
#endif
#endif
+#endif
+ SP(SCSI_MAX_SG_SEGMENTS)
};
#undef SP
@@ -692,42 +693,16 @@
return NULL;
}
-/*
- * Like SCSI_MAX_SG_SEGMENTS, but for archs that have sg chaining. This limit
- * is totally arbitrary, a setting of 2048 will get you at least 8mb ios.
- */
-#define SCSI_MAX_SG_CHAIN_SEGMENTS 2048
-
static inline unsigned int scsi_sgtable_index(unsigned short nents)
{
unsigned int index;
- switch (nents) {
- case 1 ... 8:
+ BUG_ON(nents > SCSI_MAX_SG_SEGMENTS);
+
+ if (nents <= 8)
index = 0;
- break;
- case 9 ... 16:
- index = 1;
- break;
-#if (SCSI_MAX_SG_SEGMENTS > 16)
- case 17 ... 32:
- index = 2;
- break;
-#if (SCSI_MAX_SG_SEGMENTS > 32)
- case 33 ... 64:
- index = 3;
- break;
-#if (SCSI_MAX_SG_SEGMENTS > 64)
- case 65 ... 128:
- index = 4;
- break;
-#endif
-#endif
-#endif
- default:
- printk(KERN_ERR "scsi: bad segment count=%d\n", nents);
- BUG();
- }
+ else
+ index = get_count_order(nents) - 3;
return index;
}
@@ -1603,20 +1578,7 @@
* this limit is imposed by hardware restrictions
*/
blk_queue_max_hw_segments(q, shost->sg_tablesize);
-
- /*
- * In the future, sg chaining support will be mandatory and this
- * ifdef can then go away. Right now we don't have all archs
- * converted, so better keep it safe.
- */
-#ifdef ARCH_HAS_SG_CHAIN
- if (shost->use_sg_chaining)
- blk_queue_max_phys_segments(q, SCSI_MAX_SG_CHAIN_SEGMENTS);
- else
- blk_queue_max_phys_segments(q, SCSI_MAX_SG_SEGMENTS);
-#else
- blk_queue_max_phys_segments(q, SCSI_MAX_SG_SEGMENTS);
-#endif
+ blk_queue_max_phys_segments(q, SCSI_MAX_SG_CHAIN_SEGMENTS);
blk_queue_max_sectors(q, shost->max_sectors);
blk_queue_bounce_limit(q, scsi_calculate_bounce_limit(shost));
diff --git a/drivers/scsi/stex.c b/drivers/scsi/stex.c
index e3fab3a..72f6d80 100644
--- a/drivers/scsi/stex.c
+++ b/drivers/scsi/stex.c
@@ -1123,7 +1123,6 @@
.this_id = -1,
.sg_tablesize = ST_MAX_SG,
.cmd_per_lun = ST_CMD_PER_LUN,
- .use_sg_chaining = ENABLE_SG_CHAINING,
};
static int stex_set_dma_mask(struct pci_dev * pdev)
diff --git a/drivers/scsi/sym53c416.c b/drivers/scsi/sym53c416.c
index 1f6fd16..6325901 100644
--- a/drivers/scsi/sym53c416.c
+++ b/drivers/scsi/sym53c416.c
@@ -840,6 +840,5 @@
.cmd_per_lun = 1,
.unchecked_isa_dma = 1,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
};
#include "scsi_module.c"
diff --git a/drivers/scsi/sym53c8xx_2/sym_glue.c b/drivers/scsi/sym53c8xx_2/sym_glue.c
index e939f38..d39107b 100644
--- a/drivers/scsi/sym53c8xx_2/sym_glue.c
+++ b/drivers/scsi/sym53c8xx_2/sym_glue.c
@@ -1681,7 +1681,6 @@
.eh_host_reset_handler = sym53c8xx_eh_host_reset_handler,
.this_id = 7,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
.max_sectors = 0xFFFF,
#ifdef SYM_LINUX_PROC_INFO_SUPPORT
.proc_info = sym53c8xx_proc_info,
diff --git a/drivers/scsi/u14-34f.c b/drivers/scsi/u14-34f.c
index 4bc5407..662c004 100644
--- a/drivers/scsi/u14-34f.c
+++ b/drivers/scsi/u14-34f.c
@@ -451,7 +451,6 @@
.this_id = 7,
.unchecked_isa_dma = 1,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
};
#if !defined(__BIG_ENDIAN_BITFIELD) && !defined(__LITTLE_ENDIAN_BITFIELD)
diff --git a/drivers/scsi/ultrastor.c b/drivers/scsi/ultrastor.c
index 75eca6b..f385dce 100644
--- a/drivers/scsi/ultrastor.c
+++ b/drivers/scsi/ultrastor.c
@@ -1204,6 +1204,5 @@
.cmd_per_lun = ULTRASTOR_MAX_CMDS_PER_LUN,
.unchecked_isa_dma = 1,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
};
#include "scsi_module.c"
diff --git a/drivers/scsi/wd7000.c b/drivers/scsi/wd7000.c
index b4304ae..c975c01 100644
--- a/drivers/scsi/wd7000.c
+++ b/drivers/scsi/wd7000.c
@@ -1671,7 +1671,6 @@
.cmd_per_lun = 1,
.unchecked_isa_dma = 1,
.use_clustering = ENABLE_CLUSTERING,
- .use_sg_chaining = ENABLE_SG_CHAINING,
};
#include "scsi_module.c"
diff --git a/include/scsi/scsi.h b/include/scsi/scsi.h
index 702fcfe..0f55f5b 100644
--- a/include/scsi/scsi.h
+++ b/include/scsi/scsi.h
@@ -11,6 +11,25 @@
#include <linux/types.h>
/*
+ * The maximum number of SG segments that we will put inside a
+ * scatterlist (unless chaining is used). Should ideally fit inside a
+ * single page, to avoid a higher order allocation. We could define this
+ * to SG_MAX_SINGLE_ALLOC to pack correctly at the highest order. The
+ * minimum value is 32
+ */
+#define SCSI_MAX_SG_SEGMENTS 128
+
+/*
+ * Like SCSI_MAX_SG_SEGMENTS, but for archs that have sg chaining. This limit
+ * is totally arbitrary, a setting of 2048 will get you at least 8mb ios.
+ */
+#ifdef ARCH_HAS_SG_CHAIN
+#define SCSI_MAX_SG_CHAIN_SEGMENTS 2048
+#else
+#define SCSI_MAX_SG_CHAIN_SEGMENTS SCSI_MAX_SG_SEGMENTS
+#endif
+
+/*
* SCSI command lengths
*/
diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h
index cb2bcab..5c58d59 100644
--- a/include/scsi/scsi_host.h
+++ b/include/scsi/scsi_host.h
@@ -39,9 +39,6 @@
#define DISABLE_CLUSTERING 0
#define ENABLE_CLUSTERING 1
-#define DISABLE_SG_CHAINING 0
-#define ENABLE_SG_CHAINING 1
-
enum scsi_eh_timer_return {
EH_NOT_HANDLED,
EH_HANDLED,
@@ -446,15 +443,6 @@
unsigned ordered_tag:1;
/*
- * true if the low-level driver can support sg chaining. this
- * will be removed eventually when all the drivers are
- * converted to support sg chaining.
- *
- * Status: OBSOLETE
- */
- unsigned use_sg_chaining:1;
-
- /*
* Countdown for host blocking with no commands outstanding
*/
unsigned int max_host_blocked;
@@ -598,7 +586,6 @@
unsigned unchecked_isa_dma:1;
unsigned use_clustering:1;
unsigned use_blk_tcq:1;
- unsigned use_sg_chaining:1;
/*
* Host has requested that no further requests come through for the