IB/ehca: Catch failing ioremap()

When ioremap() fails with a NULL pointer, catch the error and pass it
to the caller of create_qp() or create_cq() instead of trying to
dereference the NULL pointer later on.

Signed-off-by: Alexander Schmidt <alexs@linux.vnet.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

3 files changed, 34 insertions, 11 deletions

diff --git a/drivers/infiniband/hw/ehca/hcp_if.c b/drivers/infiniband/hw/ehca/hcp_if.c
index 4d5dc3304d42..e6f9cdd94c7a 100644
--- a/drivers/infiniband/hw/ehca/hcp_if.c
+++ b/drivers/infiniband/hw/ehca/hcp_if.c
@@ -269,6 +269,7 @@ u64 hipz_h_alloc_resource_cq(const struct ipz_adapter_handle adapter_handle,
                              struct ehca_cq *cq,
                              struct ehca_alloc_cq_parms *param)
 {
+        int rc;
         u64 ret;
         unsigned long outs[PLPAR_HCALL9_BUFSIZE];
 
@@ -283,8 +284,19 @@ u64 hipz_h_alloc_resource_cq(const struct ipz_adapter_handle adapter_handle,
         param->act_nr_of_entries = (u32)outs[3];
         param->act_pages = (u32)outs[4];
 
-        if (ret == H_SUCCESS)
-                hcp_galpas_ctor(&cq->galpas, 0, outs[5], outs[6]);
+        if (ret == H_SUCCESS) {
+                rc = hcp_galpas_ctor(&cq->galpas, 0, outs[5], outs[6]);
+                if (rc) {
+                        ehca_gen_err("Could not establish HW access. rc=%d paddr=%#lx",
+                                     rc, outs[5]);
+
+                        ehca_plpar_hcall_norets(H_FREE_RESOURCE,
+                                                adapter_handle.handle,     /* r4 */
+                                                cq->ipz_cq_handle.handle,  /* r5 */
+                                                0, 0, 0, 0, 0);
+                        ret = H_NO_MEM;
+                }
+        }
 
         if (ret == H_NOT_ENOUGH_RESOURCES)
                 ehca_gen_err("Not enough resources. ret=%lli", ret);
@@ -295,6 +307,7 @@ u64 hipz_h_alloc_resource_cq(const struct ipz_adapter_handle adapter_handle,
 u64 hipz_h_alloc_resource_qp(const struct ipz_adapter_handle adapter_handle,
                              struct ehca_alloc_qp_parms *parms, int is_user)
 {
+        int rc;
         u64 ret;
         u64 allocate_controls, max_r10_reg, r11, r12;
         unsigned long outs[PLPAR_HCALL9_BUFSIZE];
@@ -358,8 +371,19 @@ u64 hipz_h_alloc_resource_qp(const struct ipz_adapter_handle adapter_handle,
         parms->rqueue.queue_size =
                 (u32)EHCA_BMASK_GET(H_ALL_RES_QP_RQUEUE_SIZE_PAGES, outs[4]);
 
-        if (ret == H_SUCCESS)
-                hcp_galpas_ctor(&parms->galpas, is_user, outs[6], outs[6]);
+        if (ret == H_SUCCESS) {
+                rc = hcp_galpas_ctor(&parms->galpas, is_user, outs[6], outs[6]);
+                if (rc) {
+                        ehca_gen_err("Could not establish HW access. rc=%d paddr=%#lx",
+                                     rc, outs[6]);
+
+                        ehca_plpar_hcall_norets(H_FREE_RESOURCE,
+                                                adapter_handle.handle,     /* r4 */
+                                                parms->qp_handle.handle,  /* r5 */
+                                                0, 0, 0, 0, 0);
+                        ret = H_NO_MEM;
+                }
+        }
 
         if (ret == H_NOT_ENOUGH_RESOURCES)
                 ehca_gen_err("Not enough resources. ret=%lli", ret);
diff --git a/drivers/infiniband/hw/ehca/hcp_phyp.c b/drivers/infiniband/hw/ehca/hcp_phyp.c
index b3e0e72e8a73..077376ff3d28 100644
--- a/drivers/infiniband/hw/ehca/hcp_phyp.c
+++ b/drivers/infiniband/hw/ehca/hcp_phyp.c
@@ -42,10 +42,9 @@
 #include "ehca_classes.h"
 #include "hipz_hw.h"
 
-int hcall_map_page(u64 physaddr, u64 *mapaddr)
+u64 hcall_map_page(u64 physaddr)
 {
-        *mapaddr = (u64)(ioremap(physaddr, EHCA_PAGESIZE));
-        return 0;
+        return (u64)ioremap(physaddr, EHCA_PAGESIZE);
 }
 
 int hcall_unmap_page(u64 mapaddr)
@@ -58,9 +57,9 @@ int hcp_galpas_ctor(struct h_galpas *galpas, int is_user,
                     u64 paddr_kernel, u64 paddr_user)
 {
         if (!is_user) {
-                int ret = hcall_map_page(paddr_kernel, &galpas->kernel.fw_handle);
-                if (ret)
-                        return ret;
+                galpas->kernel.fw_handle = hcall_map_page(paddr_kernel);
+                if (!galpas->kernel.fw_handle)
+                        return -ENOMEM;
         } else
                 galpas->kernel.fw_handle = 0;
 
diff --git a/drivers/infiniband/hw/ehca/hcp_phyp.h b/drivers/infiniband/hw/ehca/hcp_phyp.h
index 204227d5303a..d1b029910249 100644
--- a/drivers/infiniband/hw/ehca/hcp_phyp.h
+++ b/drivers/infiniband/hw/ehca/hcp_phyp.h
@@ -83,7 +83,7 @@ int hcp_galpas_ctor(struct h_galpas *galpas, int is_user,
 
 int hcp_galpas_dtor(struct h_galpas *galpas);
 
-int hcall_map_page(u64 physaddr, u64 * mapaddr);
+u64 hcall_map_page(u64 physaddr);
 
 int hcall_unmap_page(u64 mapaddr);