IB/mthca: Add module parameter for number of MTTs per segment
The current MTT allocator uses kmalloc() to allocate a buffer for its
buddy allocator, and thus is limited in the amount of MTT segments
that it can control. As a result, the size of memory that can be
registered is limited too. This patch uses a module parameter to
control the number of MTT entries that each segment represents,
allowing more memory to be registered with the same number of
segments.
Signed-off-by: Eli Cohen <eli@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/infiniband/hw/mthca/mthca_main.c b/drivers/infiniband/hw/mthca/mthca_main.c
index 1d83cf7..13da9f1 100644
--- a/drivers/infiniband/hw/mthca/mthca_main.c
+++ b/drivers/infiniband/hw/mthca/mthca_main.c
@@ -125,6 +125,10 @@
MODULE_PARM_DESC(fmr_reserved_mtts,
"number of memory translation table segments reserved for FMR");
+static int log_mtts_per_seg = ilog2(MTHCA_MTT_SEG_SIZE / 8);
+module_param_named(log_mtts_per_seg, log_mtts_per_seg, int, 0444);
+MODULE_PARM_DESC(log_mtts_per_seg, "Log2 number of MTT entries per segment (1-5)");
+
static char mthca_version[] __devinitdata =
DRV_NAME ": Mellanox InfiniBand HCA driver v"
DRV_VERSION " (" DRV_RELDATE ")\n";
@@ -162,6 +166,7 @@
int err;
u8 status;
+ mdev->limits.mtt_seg_size = (1 << log_mtts_per_seg) * 8;
err = mthca_QUERY_DEV_LIM(mdev, dev_lim, &status);
if (err) {
mthca_err(mdev, "QUERY_DEV_LIM command failed, aborting.\n");
@@ -460,11 +465,11 @@
}
/* CPU writes to non-reserved MTTs, while HCA might DMA to reserved mtts */
- mdev->limits.reserved_mtts = ALIGN(mdev->limits.reserved_mtts * MTHCA_MTT_SEG_SIZE,
- dma_get_cache_alignment()) / MTHCA_MTT_SEG_SIZE;
+ mdev->limits.reserved_mtts = ALIGN(mdev->limits.reserved_mtts * mdev->limits.mtt_seg_size,
+ dma_get_cache_alignment()) / mdev->limits.mtt_seg_size;
mdev->mr_table.mtt_table = mthca_alloc_icm_table(mdev, init_hca->mtt_base,
- MTHCA_MTT_SEG_SIZE,
+ mdev->limits.mtt_seg_size,
mdev->limits.num_mtt_segs,
mdev->limits.reserved_mtts,
1, 0);
@@ -1315,6 +1320,12 @@
printk(KERN_WARNING PFX "Corrected fmr_reserved_mtts to %d.\n",
hca_profile.fmr_reserved_mtts);
}
+
+ if ((log_mtts_per_seg < 1) || (log_mtts_per_seg > 5)) {
+ printk(KERN_WARNING PFX "bad log_mtts_per_seg (%d). Using default - %d\n",
+ log_mtts_per_seg, ilog2(MTHCA_MTT_SEG_SIZE / 8));
+ log_mtts_per_seg = ilog2(MTHCA_MTT_SEG_SIZE / 8);
+ }
}
static int __init mthca_init(void)