[PATCH v2 18/38] cxlflash: Support process specific mappings

Uma Krishnan
2018-02-26T22:22:36Z

Once the context is started, the assigned MMIO space can be mapped
and unmapped. Provide means to map and unmap the context MMIO space.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
---
drivers/scsi/cxlflash/ocxl_hw.c | 24 ++++++++++++++++++++++++
1 file changed, 24 insertions(+)

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
index f1c55ce..67f0252 100644
--- a/drivers/scsi/cxlflash/ocxl_hw.c
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -151,6 +151,28 @@ static struct file *ocxlflash_getfile(struct device *dev, const char *name,
}

/**
+ * ocxlflash_psa_map() - map the process specific MMIO space
+ * @ctx_cookie: Adapter context for which the mapping needs to be done.
+ *
+ * Return: MMIO pointer of the mapped region
+ */
+static void __iomem *ocxlflash_psa_map(void *ctx_cookie)
+{
+ struct ocxlflash_context *ctx = ctx_cookie;
+
+ return ioremap(ctx->psn_phys, ctx->psn_size);
+}
+
+/**
+ * ocxlflash_psa_unmap() - unmap the process specific MMIO space
+ * @addr: MMIO pointer to unmap.
+ */
+static void ocxlflash_psa_unmap(void __iomem *addr)
+{
+ iounmap(addr);
+}
+
+/**
* ocxlflash_process_element() - get process element of the adapter context
* @ctx_cookie: Adapter context associated with the process element.
*
@@ -610,6 +632,8 @@ static void *ocxlflash_fops_get_context(struct file *file)
/* Backend ops to ocxlflash services */
const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
.module = THIS_MODULE,
+ .psa_map = ocxlflash_psa_map,
+ .psa_unmap = ocxlflash_psa_unmap,
.process_element = ocxlflash_process_element,
.start_context = ocxlflash_start_context,
.set_master = ocxlflash_set_master,
--
2.1.0