Enhanced DMA allocation for Sense Buffer, if the allocation does not fit
within same 4GB.Introduced is_MSB_are_same function to check if allocted
buffer within 4GB range or not.
Signed-off-by: Chaitra P B <chaitra.basappa@xxxxxxxxxxxx>
Signed-off-by: Suganath Prabu S <suganath-prabu.subramani@xxxxxxxxxxxx>
---
drivers/scsi/mpt3sas/mpt3sas_base.c | 57 +++++++++++++++++++++++++++++++++++++
1 file changed, 57 insertions(+)
diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.c b/drivers/scsi/mpt3sas/mpt3sas_base.c
index 701e1e7..7f3b684 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_base.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_base.c
@@ -4205,6 +4205,32 @@ _base_release_memory_pools(struct MPT3SAS_ADAPTER *ioc)
}
/**
+ * is_MSB_are_same - checks whether all reply queues in a set are
+ * having same upper 32bits in their base memory address.
+ * @reply_pool_start_address: Base address of a reply queue set
+ * @pool_sz: Size of single Reply Descriptor Post Queues pool size
+ *
+ * Returns 1 if reply queues in a set have a same upper 32bits
+ * in their base memory address,
+ * else 0
+ */
+
+static int
+is_MSB_are_same(long reply_pool_start_address, u32 pool_sz)
+{
+ long reply_pool_end_address;
+ unsigned long bit_divisor_16 = 0x10000;
+
+ reply_pool_end_address = reply_pool_start_address + pool_sz;
+
+ if (((reply_pool_start_address / bit_divisor_16) / (bit_divisor_16)) ==
+ ((reply_pool_end_address / bit_divisor_16) / bit_divisor_16))
+ return 1;
+ else
+ return 0;
+}
+
+/**
* _base_allocate_memory_pools - allocate start of day memory pools
* @ioc: per adapter object
*
@@ -4664,6 +4690,37 @@ _base_allocate_memory_pools(struct MPT3SAS_ADAPTER *ioc)
ioc->name);
goto out;
}
+ /* sense buffer requires to be in same 4 gb region.
+ * Below function will check the same.
+ * In case of failure, new pci pool will be created with updated
+ * alignment. Older allocation and pool will be destroyed.
+ * Alignment will be used such a way that next allocation if
+ * success, will always meet same 4gb region requirement.
+ * Actual requirement is not alignment, but we need start and end of
+ * DMA address must have same upper 32 bit address.
+ */
+ if (!is_MSB_are_same((long)ioc->sense, sz)) {
+ //Release Sense pool & Reallocate
+ dma_pool_free(ioc->sense_dma_pool, ioc->sense, ioc->sense_dma);
+ dma_pool_destroy(ioc->sense_dma_pool);
+ ioc->sense = NULL;
+
+ ioc->sense_dma_pool =
+ dma_pool_create("sense pool", &ioc->pdev->dev, sz,
+ roundup_pow_of_two(sz), 0);
+ if (!ioc->sense_dma_pool) {
+ pr_err(MPT3SAS_FMT "sense pool: pci_pool_create failed\n",
+ ioc->name);
+ goto out;
+ }
+ ioc->sense = dma_pool_alloc(ioc->sense_dma_pool, GFP_KERNEL,
+ &ioc->sense_dma);
+ if (!ioc->sense) {
+ pr_err(MPT3SAS_FMT "sense pool: pci_pool_alloc failed\n",
+ ioc->name);
+ goto out;
+ }
+ }
dinitprintk(ioc, pr_info(MPT3SAS_FMT
"sense pool(0x%p): depth(%d), element_size(%d), pool_size"
"(%d kB)\n", ioc->name, ioc->sense, ioc->scsiio_depth,
--
1.8.3.1